WorldWideScience

Sample records for callosities

  1. An Arabidopsis callose synthase

    DEFF Research Database (Denmark)

    Ostergaard, Lars; Petersen, Morten; Mattsson, Ole

    2002-01-01

    in the Arabidopsis mpk4 mutant which exhibits systemic acquired resistance (SAR), elevated beta-1,3-glucan synthase activity, and increased callose levels. In addition, AtGsl5 is a likely target of salicylic acid (SA)-dependent SAR, since AtGsl5 mRNA accumulation is induced by SA in wild-type plants, while...... expression of the nahG salicylate hydroxylase reduces AtGsl5 mRNA levels in the mpk4 mutant. These results indicate that AtGsl5 is likely involved in callose synthesis in flowering tissues and in the mpk4 mutant....

  2. Callosal warning syndrome.

    Science.gov (United States)

    Nandhagopal, Ramachandiran; Al-Asmi, Abdullah; Johnston, William James; Jacob, P C; Arunodaya, G R

    2012-03-15

    To report the clinical and imaging findings in a patient with an initial fluctuating disconnection syndrome due to corpus callosal ischemia that ultimately culminated in infarction with persistent symptoms. A 40-year-old, hypertensive, right-handed man presented with transient, stereotyped symptoms of corpus callosal disconnection (intermanual conflict, apraxia, dysgraphia and construction difficulties in his left hand). Serial magnetic resonance imaging scans demonstrated the ischemic nature of the initial fluctuating symptoms and later showed callosal infarction when the symptoms were persistent. Magnetic resonance angiogram did not reveal significant stenosis or occlusion of the internal carotid or proximal portion of anterior cerebral arteries. Patient received standard treatment for ischemic stroke and at follow-up 1 month later, had mild left hand apraxia, dysgraphia and construction difficulties. The case highlights the unusual occurrence of crescendo transient ischemic attacks culminating in infarction in the location of corpus callosum. We have termed this novel stroke syndrome as 'callosal warning syndrome' as the temporal profile was quite indistinguishable from that of relatively well-known stroke warning syndromes in the location of internal capsule and pontine tegmentum. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. CalloseMeasurer: a novel software solution to measure callose deposition and recognise spreading callose patterns

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    Zhou Ji

    2012-12-01

    Full Text Available Abstract Background Quantification of callose deposits is a useful measure for the activities of plant immunity and pathogen growth by fluorescence imaging. For robust scoring of differences, this normally requires many technical and biological replicates and manual or automated quantification of the callose deposits. However, previously available software tools for quantifying callose deposits from bioimages were limited, making batch processing of callose image data problematic. In particular, it is challenging to perform large-scale analysis on images with high background noise and fused callose deposition signals. Results We developed CalloseMeasurer, an easy-to-use application that quantifies callose deposition, a plant immune response triggered by potentially pathogenic microbes. Additionally, by tracking identified callose deposits between multiple images, the software can recognise patterns of how a given filamentous pathogen grows in plant leaves. The software has been evaluated with typical noisy experimental images and can be automatically executed without the need for user intervention. The automated analysis is achieved by using standard image analysis functions such as image enhancement, adaptive thresholding, and object segmentation, supplemented by several novel methods which filter background noise, split fused signals, perform edge-based detection, and construct networks and skeletons for extracting pathogen growth patterns. To efficiently batch process callose images, we implemented the algorithm in C/C++ within the Acapella™ framework. Using the tool we can robustly score significant differences between different plant genotypes when activating the immune response. We also provide examples for measuring the in planta hyphal growth of filamentous pathogens. Conclusions CalloseMeasurer is a new software solution for batch-processing large image data sets to quantify callose deposition in plants. We demonstrate its high

  4. Callosal ideomotor apraxia in Alzheimer's disease.

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    Cimino-Knight, Ann Marie; Gonzalez Rothi, Leslie J; He, Ying; Heilman, Kenneth M

    2017-02-01

    Impaired ability to perform skilled movements with the left upper limb in patients with corpus callosum injury has been well described (callosal apraxia) with some displaying spatial-temporal errors primarily in response to verbal commands (verbal callosal disconnection apraxia), with imitation, and when using actual tools (callosal ideomotor apraxia). Additionally some patients with callosal injury also make content errors when selecting and using the incorrect tool with their left upper limb (callosal conceptual apraxia). Interestingly, patients with Alzheimer's disease (AD) reveal anatomic evidence of callosal degeneration but callosal apraxia in AD has not been described. The purpose of this study was to learn whether patients with AD display forms of callosal apraxia. Participants were 22 right-handed patients with AD and 24 matched controls. Both upper limbs were tested by having subjects pantomime transitive movements to command and imitation. Participants also viewed pictures of an incomplete task and attempted to pantomime the action needed to complete the task. When compared to controls, the participants with AD demonstrated ideomotor and conceptual apraxias of both upper limbs; however, ideomotor apraxia of their left hand was more robust than that of their right hand, suggesting a hemispheric disconnection.

  5. Callosal alterations in pyridoxine-dependent epilepsy

    NARCIS (Netherlands)

    Friedman, S.D.; Ishak, G.E.; Poliachik, S.L.; Poliakov, A.V.; Otto, R.K.; Shaw, D.W.; Willemsen, M.A.A.P.; Bok, L.A.; Gospe, S.M., Jr.

    2014-01-01

    AIM: While there have been isolated reports of callosal morphology differences in pyridoxine-dependent epilepsy (PDE), a rare autosomal disorder caused by ALDH7A1 gene mutations, no study has systematically evaluated callosal features in a large sample of patients. This study sought to overcome this

  6. Callose synthesis during reproductive development in monocotyledonous and dicotyledonous plants.

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    Shi, Xiao; Han, Xiao; Lu, Tie-gang

    2016-01-01

    Callose, a linear β-1,3-glucan molecule, plays important roles in a variety of processes in angiosperms, including development and the response to biotic and abiotic stress. Despite the importance of callose deposition, our understanding of the roles of callose in rice reproductive development and the regulation of callose biosynthesis is limited. GLUCAN SYNTHASE-LIKE genes encode callose synthases (GSLs), which function in the production of callose at diverse sites in plants. Studies have shown that callose participated in plant reproductive development, and that the timely deposition and degradation of callose were essential for normal male gametophyte development. In this mini-review, we described conserved sequences found in GSL family proteins from monocotyledonous (Oryza sativa and Zea mays) and dicotyledonous (Arabidopsis thaliana and Glycine max) plants. We also describe the latest findings on callose biosynthesis and deposition during reproductive development and discuss future challenges in unraveling the mechanism of callose synthesis and deposition in higher plants.

  7. Callosal Disconnection Syndrome Associated with Relapsing Polychondritis.

    Science.gov (United States)

    Baba, Toru; Kanno, Shigenori; Shijo, Tomomi; Nishio, Yoshiyuki; Iizuka, Osamu; Kamimura, Naoto; Ishii, Tomonori; Mori, Etsuro

    2016-01-01

    Relapsing polychondritis (RP) is a rare inflammatory disorder of the cartilagenous structures, and it sometimes involves the central nervous system. Encephalitis associated with RP causes a wide variety of symptoms according to the affected sites. We herein report the first case of 72-year-old right-handed man who developed acute meningoencephalitis associated with RP involving the corpus callous. After immunosuppressive therapy, his symptoms dramatically improved, but difficulty in performing bimanual movements with occasional diagonistic dyspraxia in his right hand remained. Because callosal signs are easily missed, especially in acute settings, it would be useful to know that RP can sometimes cause callosal disconnection syndrome.

  8. Callosal Motor Impersistence: A Novel Disconnection Syndrome.

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    Kim, Hee Jin; Kim, Dongyeop; Won, Da-Heen; Chin, Juhee; Lee, Kwang Ho; Seo, Sang Won; Heilman, Kenneth M; Na, Duk L

    2017-06-01

    Motor impersistence, an inability to sustain a certain position or movement, is a motor-intentional disorder, caused more often by right than left hemisphere lesions. Since the right hemisphere is dominant for mediating motor persistence, callosal lesions that disconnect the left hemisphere from the right may induce impersistence of the right upper and lower limbs. After an undiagnosed left callosal infarction, a 65-year-old right-handed man suddenly developed a transient loss of volitional movement of his left leg. Five days after onset, he was admitted to our hospital with signs of callosal disconnection: left-hand agraphia and apraxia, left-hand tactile anomia, failures on cross-replication of hand postures, and intermanual conflict. He had neither weakness nor ataxia of his upper or lower extremities, but when asked to keep his arms or legs extended he could not maintain his right arm and leg in the extended position, suggesting motor impersistence in his dominant limbs. When we examined him 3 months after onset, the motor impersistence had disappeared. In conclusion, motor impersistence of dominant limbs can result from isolated callosal injury that disconnects the left hemisphere from the right hemisphere's frontal-subcortical networks.

  9. Lipid Raft, Regulator of Plasmodesmal Callose Homeostasis

    Directory of Open Access Journals (Sweden)

    Arya Bagus Boedi Iswanto

    2017-04-01

    Full Text Available Abstract: The specialized plasma membrane microdomains known as lipid rafts are enriched by sterols and sphingolipids. Lipid rafts facilitate cellular signal transduction by controlling the assembly of signaling molecules and membrane protein trafficking. Another specialized compartment of plant cells, the plasmodesmata (PD, which regulates the symplasmic intercellular movement of certain molecules between adjacent cells, also contains a phospholipid bilayer membrane. The dynamic permeability of plasmodesmata (PDs is highly controlled by plasmodesmata callose (PDC, which is synthesized by callose synthases (CalS and degraded by β-1,3-glucanases (BGs. In recent studies, remarkable observations regarding the correlation between lipid raft formation and symplasmic intracellular trafficking have been reported, and the PDC has been suggested to be the regulator of the size exclusion limit of PDs. It has been suggested that the alteration of lipid raft substances impairs PDC homeostasis, subsequently affecting PD functions. In this review, we discuss the substantial role of membrane lipid rafts in PDC homeostasis and provide avenues for understanding the fundamental behavior of the lipid raft–processed PDC.

  10. Physiology and morphology of callosal projection neurons in mouse

    Science.gov (United States)

    Ramos, Raddy L.; Tam, Danny M.; Brumberg, Joshua C.

    2008-01-01

    In the mammalian neocortex, the corpus callosum serves as the major source of interhemispheric communication, comprised of axons from callosal neurons located in supragranular (II/III) and infragranular (V/VI) layers. We sought to characterize the physiology and morphology of supragranular and infragranular callosal neurons in mice using retrograde tracers and whole-cell patch clamp recordings. Whole-cell patch clamp recordings were made from retrogradely labeled callosal neurons following unilateral injection of fluorescent latex microspheres in the contralateral sensory-motor cortex. Following recordings and biocytin dialysis, labeled neurons were reconstructed using computer-assisted camera lucida (Neurolucida) for morphological analyses. Whole-cell recordings revealed that callosal neurons in both supra- and infragranular layers display very similar intrinsic membrane properties and are characteristic regular-spiking neurons. Morphological features examined from biocytin filled reconstructions as well as retrogradely BDA labeled cells did not reveal any differences. Analysis of spontaneous postsynaptic potentials from callosal neurons did reveal several differences including average amplitude, frequency, and decay time. These findings suggest that callosal neurons in both supra- and infragranular layers have similar phenotypes though belong to different local, intracortical networks. PMID:18424008

  11. Selective serotonergic excitation of callosal projection neurons

    Directory of Open Access Journals (Sweden)

    Daniel eAvesar

    2012-03-01

    Full Text Available Serotonin (5-HT acting as a neurotransmitter in the cerebral cortex is critical for cognitive function, yet how 5-HT regulates information processing in cortical circuits is not well understood. We tested the serotonergic responsiveness of layer 5 pyramidal neurons (L5PNs of the mouse medial prefrontal cortex (mPFC, and found 3 distinct response types: long-lasting 5-HT1A (1A receptor-dependent inhibitory responses (84% of L5PNs, 5-HT2A (2A receptor-dependent excitatory responses (9%, and biphasic responses in which 2A-dependent excitation followed brief inhibition (5%. Relative to 5-HT-inhibited neurons, those excited by 5-HT had physiological properties characteristic of callosal/commissural (COM neurons that project to the contralateral cortex. We tested whether serotonergic responses in cortical pyramidal neurons are correlated with their axonal projection pattern using retrograde fluorescent labeling of COM and corticopontine-projecting (CPn neurons. 5-HT generated excitatory or biphasic responses in all 5-HT-responsive layer 5 COM neurons. Conversely, CPn neurons were universally inhibited by 5-HT. Serotonergic excitation of COM neurons was blocked by the 2A antagonist MDL 11939, while serotonergic inhibition of CPn neurons was blocked by the 1A antagonist WAY 100635, confirming a role for these two receptor subtypes in regulating pyramidal neuron activity. Selective serotonergic excitation of COM neurons was not layer-specific, as COM neurons in layer 2/3 were also selectively excited by 5-HT relative to their non-labeled pyramidal neuron neighbors. Because neocortical 2A receptors are implicated in the etiology and pathophysiology of schizophrenia, we propose that COM neurons may represent a novel cellular target for intervention in psychiatric disease.

  12. [Callose accumulation during treatment of tomato (Lycopersicon esculentum L.) cells with biotic elicitors].

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    Emel'ianov, V I; Kravchuk, Zh N; Poliakovskiĭ, S A; Dmitriev, A P

    2008-01-01

    Time-course of induced accumulation of callose in tomato cells has been studied. Localization of callose in L. esculenthum cells was investigated by fluorescent microscopy technique, and the optimal time for its determination was found. Callose accumulation in tomato cells treated with different biotic elicitors was determined. Nonlinear dependence between callose accumulation and concentration of chitin oligomers (with 3-5 N-acetylglucosamine fragments) was established. Increasing of callose accumulation in tomato cells was proportional to the increase of concentration ofchitin dimer and chitosan in the culture medium.

  13. Agnosia, apraxia, callosal disconnection and other specific cognitive disorders.

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    Acciarresi, Monica

    2012-01-01

    Cortical function deficits have long been studied by anatomoclinic correlations. Recent functional imaging studies have allowed scientists to better understand which cerebral areas and which networks are involved in cognitive function deficit. This chapter will review the current knowledge on agnosia, apraxia and callosal disconnection syndromes. Copyright © 2012 S. Karger AG, Basel.

  14. Callose plug deposition patterns vary in pollen tubes of Arabidopsis thaliana ecotypes and tomato species

    Directory of Open Access Journals (Sweden)

    Qin Peng

    2012-10-01

    Full Text Available Abstract Background The pollen grain contains the male gametophyte that extends a pollen tube that grows through female tissues in order to deliver sperm to the embryo sac for double fertilization. Growing pollen tubes form periodic callose plugs that are thought to block off the older parts of the tube and maintain the cytoplasm near the growing tip. The morphology of callose plugs and the patterns of their deposition were previously shown to vary among species, but variation within a species had not been examined. We therefore systematically examined callose plug deposition in Arabidopsis thaliana ecotypes, tested for heritability using reciprocal crosses between ecotypes that had differing deposition patterns, and investigated the relationship between callose plugs and pollen tube growth rate. We also surveyed callose plug deposition patterns in different species of tomato. Results We used in vitro grown pollen tubes of 14 different A. thaliana ecotypes and measured the distance from the pollen grain pore to the first callose plug (termed first interval. This distance varied among Arabidopsis ecotypes and in some cases even within an ecotype. Pollen tubes without a callose plug were shorter than those with a callose plug, and tubes with a callose plug near the grain were, on average, longer than those with the first callose plug farther from the grain. Variations in the first callose plug position were also observed between different species of tomato. Conclusions We showed that the position of the first callose plug varied among Arabidopsis ecotypes and in tomato species, and that callose plug deposition patterns were heritable. These findings lay a foundation for mapping genes that regulate callose plug deposition or that determine pollen tube length or growth rate.

  15. Callosal microstructural abnormalities in Alzheimer's disease and alcoholism: same phenotype, different mechanisms.

    Science.gov (United States)

    Pitel, Anne-Lise; Chanraud, Sandra; Sullivan, Edith V; Pfefferbaum, Adolf

    2010-10-30

    Magnetic resonance (MRI) and diffusion tensor imaging (DTI) data were acquired in 13 Alzheimer's disease (AD) patients, 15 elderly alcoholics, and 32 elderly controls. Midsagittal area, length, dorsoventral height, fractional anisotropy (FA), and mean diffusivity (MD) of the total corpus callosum and volume of the lateral ventricles were measured; area, FA, and MD were also determined for the callosal genu, body, and splenium. On DTI, both patient groups had lower FA and higher MD than controls in all callosal regions. On MRI, both patient groups had smaller genu than controls; additional size deficits were present in the alcoholism group's callosal body and the AD group's splenium. The callosal arch was higher in the AD but not the alcoholic group compared with controls. The two patient groups had larger ventricles than controls, and the AD group had larger ventricles than the alcoholic group. Callosal area correlated with its height, and callosal FA and MD correlated with ventricular volume in AD, whereas callosal area correlated only with FA in alcoholics. In AD, the disruption of the callosal integrity, which was associated with distorted callosal shape, was related to ventricular dilation, which has been shown in twin studies to be under a multitude of genetic, polygenetic, and environmental influences. Conversely, in alcoholism, disruption of callosal microstructural integrity was related to shrinkage of the corpus callosum itself. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  16. Callosal Microstructural Abnormalities in Alzheimer Disease and Alcoholism: Same Phenotype, Different Mechanisms

    Science.gov (United States)

    Pitel, Anne-Lise; Chanraud, Sandra; Sullivan, Edith V.; Pfefferbaum, Adolf

    2010-01-01

    Magnetic resonance (MRI) and diffusion tensor imaging (DTI) data were acquired in 13 AD patients, 15 elderly alcoholics, and 32 elderly controls. Midsagittal area, length, dorsoventral height, fractional anisotropy (FA), and mean diffusivity (MD) of the total corpus callosum and volume of the lateral ventricles were measured; area, FA, and MD were also determined for the callosal genu, body, and splenium. On DTI, both patient groups had lower FA and higher MD than controls in all callosal regions. On MRI, both patient groups had smaller genu than controls; additional size deficits were presents in the alcoholic's callosal body and the AD splenium. The callosal arch was higher in the AD but not the alcoholic group compared with controls. The two patient groups had larger ventricles than controls, and the AD had larger ventricles than alcoholics. Callosal area correlated with its height, and callosal FA and MD correlated with ventricular volume in AD, whereas callosal area correlated only with FA in alcoholics. In AD, the disruption of the callosal integrity, which was associated with distorted callosal shape, was related to ventricular dilation, which has been shown in twin studies to be under a multitude of genetic, polygenetic, and environmental influences. Conversely, in alcoholism, disruption of callosal microstructural integrity is related to shrinkage of the corpus callosum itself. PMID:20832253

  17. Deposition of callose in young ovules of two Taraxacum species varying in the mode of reproduction.

    Science.gov (United States)

    Musiał, Krystyna; Kościńska-Pająk, Maria; Antolec, Renata; Joachimiak, Andrzej J

    2015-01-01

    Although callose occurs during megasporogenesis in most flowering plants, the knowledge about its general function and the mechanisms by which the callose layer is formed in particular places is still not sufficient. The results of previous studies suggest a total lack of callose in the ovules of diplosporous plants in which meiosis is omitted or disturbed. This report is the first documentation of callose events in dandelions ovules. We demonstrated the pattern of callose deposition during the formation of megaspores through diplospory of Taraxacum type and during normal meiotic megasporogenesis in apomictic triploid Taraxacum atricapillum and amphimictic diploid Taraxacum linearisquameum. We found the presence of callose in the megasporocyte wall of both diplosporous and sexual dandelions. However, in a diplosporous dandelion, callose predominated at the micropylar pole of megaspore mother cell (MMC) which may be correlated with abnormal asynaptic meiosis and may indicate diplospory of the Taraxacum type. After meiotic division, callose is mainly deposited in the walls between megaspores in tetrads and in diplodyads. In subsequent stages, callose gradually disappears around the chalazal functional megaspore. However, some variations in the pattern of callose deposition within tetrad may reflect variable positioning of the functional megaspore (FM) observed in the ovules of T. linearisquameum.

  18. Atypical Callosal Morphology in Children with Speech Sound Disorder.

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    Luders, Eileen; Kurth, Florian; Pigdon, Lauren; Conti-Ramsden, Gina; Reilly, Sheena; Morgan, Angela T

    2017-12-26

    Speech sound disorder (SSD) is common, yet its neurobiology is poorly understood. Recent studies indicate atypical structural and functional anomalies either in one hemisphere or both hemispheres, which might be accompanied by alterations in inter-hemispheric connectivity. Indeed, abnormalities of the corpus callosum - the main fiber tract connecting the two hemispheres - have been linked to speech and language deficits in associated disorders, such as stuttering, dyslexia, aphasia, etc. However, there is a dearth of studies examining the corpus callosum in SSD. Here, we investigated whether a sample of 18 children with SSD differed in callosal morphology from 18 typically developing children carefully matched for age. Significantly reduced dimensions of the corpus callosum, particularly in the callosal anterior third, were observed in children with SSD. These findings indicating pronounced callosal aberrations in SSD make an important contribution to an understudied field of research and may suggest that SSD is accompanied by atypical lateralization of speech and language function. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Developmental malformation of the corpus callosum: a review of typical callosal development and examples of developmental disorders with callosal involvement.

    Science.gov (United States)

    Paul, Lynn K

    2011-03-01

    This review provides an overview of the involvement of the corpus callosum (CC) in a variety of developmental disorders that are currently defined exclusively by genetics, developmental insult, and/or behavior. I begin with a general review of CC development, connectivity, and function, followed by discussion of the research methods typically utilized to study the callosum. The bulk of the review concentrates on specific developmental disorders, beginning with agenesis of the corpus callosum (AgCC)-the only condition diagnosed exclusively by callosal anatomy. This is followed by a review of several genetic disorders that commonly result in social impairments and/or psychopathology similar to AgCC (neurofibromatosis-1, Turner syndrome, 22q11.2 deletion syndrome, Williams yndrome, and fragile X) and two forms of prenatal injury (premature birth, fetal alcohol syndrome) known to impact callosal development. Finally, I examine callosal involvement in several common developmental disorders defined exclusively by behavioral patterns (developmental language delay, dyslexia, attention-deficit hyperactive disorder, autism spectrum disorders, and Tourette syndrome).

  20. Comparative Studies on Callose Formation in Powdery Mildew Compatible and Incompatible Barley

    DEFF Research Database (Denmark)

    Skou, Jens-Peder; Jørgensen, Jørgen Helms; Lilholt, Ulla

    1984-01-01

    Callose formation in barley mutants, lines and varieties with different genes for resistance to powdery mildew in seven different loci was compared. Only barley with resistance genes in the ml-o locus showed so early a callose formation passing off at such a high rate that it prevented fungal pen...

  1. Relationship between teat-end callosity and occurrence of clinical mastitis

    NARCIS (Netherlands)

    Neijenhuis, F.; Barkema, H.W.; Hogeveen, H.

    2001-01-01

    A longitudinal study in 15 herds, with a total of 2157 cows, was conducted to examine the relationship between teat-end callosity (TEC) and the incidence of clinical mastitis. During the 1.5-yr study period, clinical mastitis was diagnosed by the farmers based on clinical signs. Teat-end callosity

  2. Callosal transfer of finger localization information in phonologically dyslexic adults.

    Science.gov (United States)

    Moore, L H; Brown, W S; Markee, T E; Theberge, D C; Zvi, J C

    1996-06-01

    Dyslexia, particularly phonological dyslexia, has been hypothesized to be associated with deficits in interhemispheric interactions mediated by the corpus callosum. Twenty-one dyslexic subjects were compared to 21 controls on the Finger Localization Test in order to observe patterns of tactile-motor integration and interhemispheric collaboration. When compared to control subjects, dyslexics showed consistent deficits in finger localization, particularly when more complex trials had to be completed. When subjects were re-grouped according to phonological processing ability (regardless of diagnostic group membership), subjects with lower phonological processing scores were found to perform poorly on complex trials of finger localization, particularly on those trials which reflect callosal transfer of finger localization information from one hemisphere (hand) to the other. These results suggest that interhemispheric transfer of information is critical to efficient phonological processing.

  3. Motor callosal disconnection in early relapsing-remitting multiple sclerosis.

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    Wahl, Mathias; Hübers, Annemarie; Lauterbach-Soon, Birgit; Hattingen, Elke; Jung, Patrick; Cohen, Leonardo G; Ziemann, Ulf

    2011-06-01

    In relapsing-remitting multiple sclerosis (RRMS) the corpus callosum (CC) is often and early affected by macroscopic lesions when investigated by conventional MRI. We sought to determine to which extent microstructural and effective disconnection of the CC are already present in RRMS patients at the earliest stages of the disease prior to evidence of macroscopic CC lesion. We compared 16 very early RRMS patients (median expanded disability status scale (EDSS), 1.5; range, 0-2.0) to an age-matched group of healthy controls and focused analysis to the motor CC, i.e. that part of the CC relaying interhemispheric motor information. A combined functional magnetic resonance imaging/diffusion tensor imaging fiber-tracking procedure was applied to identify the callosal motor fibers (CMFs) connecting the hand areas of the primary motor cortices of the two hemispheres. Fractional anisotropy (FA) within the motor CC (FA-CC) assessed the CMF microstructural integrity. Bifocal paired transcranial magnetic stimulation (TMS) tested short-interval interhemispheric inhibition (S-IHI), an established measure of CMF effective connectivity. FA-CC and S-IHI were significantly reduced in early RRMS compared to healthy controls. Furthermore, a significant linear correlation between microstructure (FA-CC) and function (S-IHI) in the controls was broken down in the patients. These abnormalities were obtained in the absence of macroscopic CMF lesion in conventional MRI, and whilst motor hand/arm function in the nine-hole-peg test and corticospinal conduction time were normal. Findings suggest that reductions in FA and S-IHI may serve as surrogate markers of motor callosal disconnection at the earliest stages of RRMS prior to development of macroscopic lesion. Copyright © 2010 Wiley-Liss, Inc.

  4. Interhemispheric Lipoma, Callosal Anomaly, and Malformations of Cortical Development: A Case Series

    NARCIS (Netherlands)

    Niwa, Tetsu; de Vries, Linda S.|info:eu-repo/dai/nl/072995408; Manten, GTR|info:eu-repo/dai/nl/261633325; Lequin, Maarten; Cuppen, Inge; Shibasaki, Jun; Aida, Noriko

    Intracranial lipomas are rare congenital malformations. The most common type of intracranial lipoma is the interhemispheric lipoma, which is frequently associated with callosal anomalies such as hypogenesis or agenesis of the corpus callosum. In contrast, interhemispheric lipomas are less often

  5. Why Size Matters: Differences in Brain Volume Account for Apparent Sex Differences in Callosal Anatomy

    OpenAIRE

    Luders, Eileen; Toga, Arthur W.; Thompson, Paul M.

    2013-01-01

    Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus...

  6. [Callosal disconnection syndrome due to acute disseminated enchephalomyelitis].

    Science.gov (United States)

    Tanaka, Yuji; Nishida, Hiroshi; Hayashi, Rumiko; Inuzuka, Takashi; Otsuki, Mika

    2006-01-01

    We have reported a very rare case of a patient with callosal disconnection syndrome due to acute disseminated enchephalomyelitis (ADEM). A 54-year-old right-handed woman developed sudden consciousness disturbance and fever after 2 weeks when she had common cold. She did not have a history of stuttering. On admission, the neurological finding showed consciousness disturbance, and exaggerated muscle stretch reflex in four extremities without meningeal irritation. The cerebrospinal fluid examination revealed the cell counts of 273/mm3, the protein of 348 mg/dl and the myelin basic protein 18.3 pg/ml. The brain MRI demonstrated a focal high signal intensity in the right cerebellar peduncle, right temporal lobe, left occipital lobe and corpus callosum on the T2-weighted and FLAIR images. The lesion of corpus callosum was the trunk and splenium, sparing the dorsal side of splenium. Her diagnosis was ADEM. The steroid pulse therapy (metylpredinisolone 1 g/day for 3 days) improved the consciousness disturbance. After 6 weeks from the onset, the neuropsycological examination was performed. The remarkable findings included pure alexia without color naming defects, the acquired stuttering and one-way disturbance of somesthetic transfer from the left hand to the right. This patient may contribute to the study of functional localization of the corpus callosum.

  7. Protooncogene Ski cooperates with the chromatin-remodeling factor Satb2 in specifying callosal neurons.

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    Baranek, Constanze; Dittrich, Manuela; Parthasarathy, Srinivas; Bonnon, Carine Gaiser; Britanova, Olga; Lanshakov, Dmitriy; Boukhtouche, Fatiha; Sommer, Julia E; Colmenares, Clemencia; Tarabykin, Victor; Atanasoski, Suzana

    2012-02-28

    First insights into the molecular programs orchestrating the progression from neural stem cells to cortical projection neurons are emerging. Loss of the transcriptional regulator Ski has been linked to the human 1p36 deletion syndrome, which includes central nervous system defects. Here, we report critical roles for Ski in the maintenance of the neural stem cell pool and the specification of callosal neurons. Ski-deficient callosal neurons lose their identity and ectopically express the transcription factor Ctip2. The misspecified callosal neurons largely fail to form the corpus callosum and instead redirect their axons toward subcortical targets. We identify the chromatin-remodeling factor Satb2 as a partner of Ski, and show that both proteins are required for transcriptional repression of Ctip2 in callosal neurons. We propose a model in which Satb2 recruits Ski to the Ctip2 locus, and Ski attracts histone deacetylases, thereby enabling the formation of a functional nucleosome remodeling and deacetylase repressor complex. Our findings establish a central role for Ski-Satb2 interactions in regulating transcriptional mechanisms of callosal neuron specification.

  8. Callosal Thickness Reductions relate to Facial Dysmorphology in Fetal Alcohol Spectrum Disorders

    Science.gov (United States)

    Yang, Yaling; Phillips, Owen R.; Kan, Eric; Sulik, Kathleen K.; Mattson, Sarah N.; Riley, Edward P.; Jones, Kenneth L.; Adnams, Colleen M.; May, Philip A.; O’Connor, Mary J.; Narr, Katherine L.; Sowell, Elizabeth R.

    2011-01-01

    Background Structural abnormalities of the corpus callosum (CC), such as reduced size and increased shape variability, have been documented in individuals with fetal alcohol spectrum disorders (FASD). However, the regional specificity of altered CC structure, which may point to the timing of neurodevelopmental disturbances and/or relate to specific functional impairments, is unclear. Further, associations between facial dysmorphology and callosal structure remain undetermined. Method 153 participants (age range 8–16) including 82 subjects with FASD and 71 non-exposed controls were included in this study. The structural magnetic resonance imaging (sMRI) data of these subjects was collected at 3 sites (Los Angeles and San Diego, California, and Cape Town, South Africa) and analyzed using classical parcellation schemes as well as more refined surface based geometrical modeling methods to identify callosal morphological alterations in FASD at high spatial resolution. Results Reductions in callosal thickness and area, specifically in the anterior third and the splenium, were observed in FASD compared to non-exposed controls. In addition, reduced CC thickness and area significantly correlated with reduced palpebral fissure length. Conclusions Consistent with previous reports, findings suggest an adverse effect of prenatal alcohol exposure on callosal growth and further indicate that fiber pathways connecting frontal and parieto-occipital regions in each hemisphere may be particularly affected. Significant associations between callosal and facial dysmorphology provide evidence for a concurrent insult to midline facial and brain structural development in FASD. PMID:22150665

  9. Persistent activation of microglia is associated with neuronal dysfunction of callosal projecting pathways and multiple sclerosis-like lesions in relapsing--remitting experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Rasmussen, Stine; Wang, Yue; Kivisäkk, Pia

    2007-01-01

    Cortical pathology, callosal atrophy and axonal loss are substrates of progression in multiple sclerosis (MS). Here we describe cortical, periventricular subcortical lesions and callosal demyelination in relapsing-remitting experimental autoimmune encephalomyelitis in SJL mice that are similar to...

  10. Transient neuronal populations are required to guide callosal axons: a role for semaphorin 3C.

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    Mathieu Niquille

    2009-10-01

    Full Text Available The corpus callosum (CC is the main pathway responsible for interhemispheric communication. CC agenesis is associated with numerous human pathologies, suggesting that a range of developmental defects can result in abnormalities in this structure. Midline glial cells are known to play a role in CC development, but we here show that two transient populations of midline neurons also make major contributions to the formation of this commissure. We report that these two neuronal populations enter the CC midline prior to the arrival of callosal pioneer axons. Using a combination of mutant analysis and in vitro assays, we demonstrate that CC neurons are necessary for normal callosal axon navigation. They exert an attractive influence on callosal axons, in part via Semaphorin 3C and its receptor Neuropilin-1. By revealing a novel and essential role for these neuronal populations in the pathfinding of a major cerebral commissure, our study brings new perspectives to pathophysiological mechanisms altering CC formation.

  11. Role of callose synthases in transfer cell wall development in tocopherol deficient Arabidopsis mutants

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    Hiroshi eMaeda

    2014-02-01

    Full Text Available Tocopherols (vitamin E are lipid-soluble antioxidants produced by all plants and algae, and many cyanobacteria, yet their functions in these photosynthetic organisms are still not fully understood. We have previously reported that the vitamin E deficient 2 (vte2 mutant of Arabidopsis thaliana is sensitive to low temperature (LT due to impaired transfer cell wall (TCW development and photoassimilate export, associated with massive callose deposition in transfer cells of the phloem. To further understand the role of tocopherols in LT induced TCW development we compared global transcript profiles of vte2 and wild type leaves during LT treatment. Tocopherol deficiency had no impact on global gene expression in permissive conditions, but affected expression of 77 genes after 48 hours of LT treatment. In vte2 relative to wild type, genes related with solute transport were repressed, while those involved in various pathogen responses and cell wall modifications, such as GLUCAN SYNTHASE LIKE genes (GSL4 and GSL11, were induced. However, introduction of gsl4 or gsl11 mutations into the vte2 background did not suppress callose deposition or the overall LT-induced phenotypes of vte2. Intriguingly, introduction of a mutation of GSL5, the major GSL responsible for pathogen-induced callose deposition, into vte2 substantially reduced vascular callose deposition at LT, but again had no effect on the photoassimilate export phenotype of LT-treated vte2. These results suggest that GSL5 plays a major role in TCW callose deposition in LT-treated vte2 but that this GSL5-dependent callose deposition is not the primary cause of the impaired photoassimilate export phenotype.

  12. Cognitive Control and White Matter Callosal Microstructure in Methamphetamine Dependent Subjects: A DTI Study

    Science.gov (United States)

    Salo, Ruth; Nordahl, Thomas E; Buonocore, Michael H; Natsuaki, Yutaka; Waters, Christy; Moore, Charles D; Galloway, Gantt P; Leamon, Martin H

    2009-01-01

    Background Methamphetamine (MA) abuse causes damage to structures within the human cerebrum, with particular susceptibility to white matter (WM). Abnormalities have been reported in anterior regions with less evidence of changes in posterior regions. MA abusers have also shown deficits on attention tests that measure response conflict and cognitive control. Methods We examined cognitive control using a computerized measure of the Stroop selective attention task and indices of WM microstructure obtained from diffusion tensor imaging (DTI) in the callosal genu and splenium of 37 currently abstinent MA abusers and 17 non-substance abusing controls. Measurements of Fractional Anisotropy (FA), apparent diffusion coefficient (ADC) of callosal fibers and diffusion tensor eigenvalues were obtained in all subjects. Results The MA abusers exhibited greater Stroop reaction time interference (i.e., reduced cognitive control) [p=.04] compared to controls. After correcting for multiple comparisons, FA within the genu correlated significantly with measures of cognitive control in the MA abusers [p=.04, bonferroni corrected] but not in controls [p=.26]. Group differences in genu, but not splenium, FA were trend significant [p=.09]. Conclusions MA abuse appears to alter anterior callosal WM microstructure with less evidence of change within posterior callosal WM microstructure. DTI indices within the genu, but not splenium, correlated with measures of cognitive control in chronic MA abusers. PMID:18814867

  13. The enhanced callose deposition in barley with ml-o powdery mildew resistance genes

    DEFF Research Database (Denmark)

    Skou, Jens-Peder

    1985-01-01

    Carborundum treatment of barley leaves induced a callose deposition which was detected as diffuse blotches in the epidermal cells of susceptible barleys and as deeply stained tracks along the scratches in barleys with the ml-o powdery mildew resistance gene. Subsequent inoculation with powdery mi...

  14. Reorganization of Visual Callosal Connections Following Alterations of Retinal Input and Brain Damage.

    Science.gov (United States)

    Restani, Laura; Caleo, Matteo

    2016-01-01

    Vision is a very important sensory modality in humans. Visual disorders are numerous and arising from diverse and complex causes. Deficits in visual function are highly disabling from a social point of view and in addition cause a considerable economic burden. For all these reasons there is an intense effort by the scientific community to gather knowledge on visual deficit mechanisms and to find possible new strategies for recovery and treatment. In this review, we focus on an important and sometimes neglected player of the visual function, the corpus callosum (CC). The CC is the major white matter structure in the brain and is involved in information processing between the two hemispheres. In particular, visual callosal connections interconnect homologous areas of visual cortices, binding together the two halves of the visual field. This interhemispheric communication plays a significant role in visual cortical output. Here, we will first review the essential literature on the physiology of the callosal connections in normal vision. The available data support the view that the callosum contributes to both excitation and inhibition to the target hemisphere, with a dynamic adaptation to the strength of the incoming visual input. Next, we will focus on data showing how callosal connections may sense visual alterations and respond to the classical paradigm for the study of visual plasticity, i.e., monocular deprivation (MD). This is a prototypical example of a model for the study of callosal plasticity in pathological conditions (e.g., strabismus and amblyopia) characterized by unbalanced input from the two eyes. We will also discuss the findings of callosal alterations in blind subjects. Noteworthy, we will discuss data showing that inter-hemispheric transfer mediates recovery of visual responsiveness following cortical damage. Finally, we will provide an overview of how callosal projections dysfunction could contribute to pathologies such as neglect and occipital

  15. REORGANIZATION OF VISUAL CALLOSAL CONNECTIONS FOLLOWING ALTERATIONS OF RETINAL INPUT AND BRAIN DAMAGE

    Directory of Open Access Journals (Sweden)

    LAURA RESTANI

    2016-11-01

    Full Text Available Vision is a very important sensory modality in humans. Visual disorders are numerous and arising from diverse and complex causes. Deficits in visual function are highly disabling from a social point of view and in addition cause a considerable economic burden. For all these reasons there is an intense effort by the scientific community to gather knowledge on visual deficit mechanisms and to find possible new strategies for recovery and treatment. In this review we focus on an important and sometimes neglected player of the visual function, the corpus callosum (CC. The CC is the major white matter structure in the brain and is involved in information processing between the two hemispheres. In particular, visual callosal connections interconnect homologous areas of visual cortices, binding together the two halves of the visual field. This interhemispheric communication plays a significant role in visual cortical output. Here, we will first review essential literature on the physiology of the callosal connections in normal vision. The available data support the view that the callosum contributes to both excitation and inhibition to the target hemisphere, with a dynamic adaptation to the strength of the incoming visual input. Next, we will focus on data showing how callosal connections may sense visual alterations and respond to the classical paradigm for the study of visual plasticity, i.e. monocular deprivation. This is a prototypical example of a model for the study of callosal plasticity in pathological conditions (e.g. strabismus and amblyopia characterized by unbalanced input from the two eyes. We will also discuss findings of callosal alterations in blind subjects. Noteworthy, we will discuss data showing that inter-hemispheric transfer mediates recovery of visual responsiveness following cortical damage. Finally, we will provide an overview of how callosal projections dysfunction could contribute to pathologies such as neglect and occipital

  16. The Plasmodesmal Protein PDLP1 Localises to Haustoria-Associated Membranes during Downy Mildew Infection and Regulates Callose Deposition

    Science.gov (United States)

    Sklenar, Jan; Findlay, Kim; Piquerez, Sophie J. M.; Jones, Alexandra M. E.; Robatzek, Silke; Jones, Jonathan D. G.; Faulkner, Christine

    2014-01-01

    The downy mildew pathogen Hyaloperonospora arabidopsidis (Hpa) is a filamentous oomycete that invades plant cells via sophisticated but poorly understood structures called haustoria. Haustoria are separated from the host cell cytoplasm and surrounded by an extrahaustorial membrane (EHM) of unknown origin. In some interactions, including Hpa-Arabidopsis, haustoria are progressively encased by host-derived, callose-rich materials but the molecular mechanisms by which callose accumulates around haustoria remain unclear. Here, we report that PLASMODESMATA-LOCATED PROTEIN 1 (PDLP1) is expressed at high levels in Hpa infected cells. Unlike other plasma membrane proteins, which are often excluded from the EHM, PDLP1 is located at the EHM in Hpa-infected cells prior to encasement. The transmembrane domain and cytoplasmic tail of PDLP1 are sufficient to convey this localization. PDLP1 also associates with the developing encasement but this association is lost when encasements are fully mature. We found that the pdlp1,2,3 triple mutant is more susceptible to Hpa while overexpression of PDLP1 enhances plant resistance, suggesting that PDLPs enhance basal immunity against Hpa. Haustorial encasements are depleted in callose in pdlp1,2,3 mutant plants whereas PDLP1 over-expression elevates callose deposition around haustoria and across the cell surface. These data indicate that PDLPs contribute to callose encasement of Hpa haustoria and suggests that the deposition of callose at haustoria may involve similar mechanisms to callose deposition at plasmodesmata. PMID:25393742

  17. Differential Callosal Contributions to Bimanual Control in Young and Older Adults

    Science.gov (United States)

    Fling, Brett W.; Walsh, Christine M.; Bangert, Ashley S.; Reuter-Lorenz, Patricia A.; Welsh, Robert C.; Seidler, Rachael D.

    2013-01-01

    Our recent work has shown that older adults are disproportionately impaired at bimanual tasks when the two hands are moving out of phase with each other [Bangert, A. S., Reuter-Lorenz, P. A., Walsh, C. M., Schachter, A. B., & Seidler, R. D. Bimanual coordination and aging: Neurobehavioral implications. Neuropsychologia, 48, 1165–1170, 2010]. Interhemispheric interactions play a key role during such bimanual movements to prevent interference from the opposite hemisphere. Declines in corpus callosum (CC) size and microstructure with advancing age have been well documented, but their contributions to age deficits in bimanual function have not been identified. In the current study, we used structural magnetic resonance and diffusion tensor imaging to investigate age-related changes in the relationships between callosal macrostructure, microstructure, and motor performance on tapping tasks requiring differing degrees of interhemispheric interaction. We found that older adults demonstrated disproportionately poorer performance on out-of-phase bimanual control, replicating our previous results. In addition, older adults had smaller anterior CC size and poorer white matter integrity in the callosal midbody than their younger counterparts. Surprisingly, larger CC size and better integrity of callosal microstructure in regions connecting sensorimotor cortices were associated with poorer motor performance on tasks requiring high levels of interhemispheric interaction in young adults. Conversely, in older adults, better performance on these tasks was associated with larger size and better CC microstructure integrity within the same callosal regions. These findings implicate age-related declines in callosal size and integrity as a key contributor to bimanual control deficits. Further, the differential age-related involvement of transcallosal pathways reported here raises new questions about the role of the CC in bimanual control. PMID:20954936

  18. Silicon amendment to rice plants contributes to reduced feeding in a phloem-sucking insect through modulation of callose deposition.

    Science.gov (United States)

    Yang, Lang; Li, Pei; Li, Fei; Ali, Shahbaz; Sun, Xiaoqin; Hou, Maolin

    2018-01-01

    Silicon (Si) uptake by Poaceae plants has beneficial effects on herbivore defense. Increased plant physical barrier and altered herbivorous feeding behaviors are documented to reduce herbivorous arthropod feeding and contribute to enhanced plant defense. Here, we show that Si amendment to rice (Oryza sativa) plants contributes to reduced feeding in a phloem feeder, the brown planthopper (Nilaparvata lugens, BPH), through modulation of callose deposition. We associated the temporal dynamics of BPH feeding with callose deposition on sieve plates and further with callose synthase and hydrolase gene expression in plants amended with Si. Biological assays revealed that BPH feeding was lower in Si-amended than in nonamended plants in the early stages post-BPH infestation. Histological observation showed that BPH infestation triggered fast and strong callose deposition in Si-amended plants compared with nonamended plants. Analysis using qRT-PCR revealed that expression of the callose synthase gene OsGSL1 was up-regulated more and that the callose hydrolase (β-1,3-glucanase) gene Gns5 was up-regulated less in Si-amended than in nonamended plants during the initial stages of BPH infestation. These dynamic expression levels of OsGSL1 and Gns5 in response to BPH infestation correspond to callose deposition patterns in Si-amended versus nonamended plants. It is demonstrated here that BPH infestation triggers differential gene expression associated with callose synthesis and hydrolysis in Si-amended and nonamended rice plants, which allows callose to be deposited more on sieve tubes and sieve tube occlusions to be maintained more thus contributing to reduced BPH feeding on Si-amended plants.

  19. Altered callose deposition during embryo sac formation of multi-pistil mutant (mp1) in Medicago sativa.

    Science.gov (United States)

    Zhou, H C; Jin, L; Li, J; Wang, X J

    2016-06-03

    Whether callose deposition is the cause or result of ovule sterility in Medicago sativa remains controversial, because it is unclear when and where changes in callose deposition and dissolution occur during fertile and sterile embryo sac formation. Here, alfalfa spontaneous multi-pistil mutant (mp1) and wild-type plants were used to compare the dynamics of callose deposition during embryo sac formation using microscopy. The results showed that both mutant and wild-type plants experienced megasporogenesis and megagametogenesis, and there was no significant difference during megasporogenesis. In contrast to the wild-type plants, in which the mature embryo sac was observed after three continuous cycles of mitosis, functional megaspores of mutant plants developed abnormally after the second round of mitosis, leading to degeneration of synergid, central, and antipodal cells. Callose deposition in both mutant and wild-type plants was first observed in the walls of megasporocytes, and then in the megaspore tetrad walls. After meiosis, the callose wall began to degrade as the functional megaspore underwent mitosis, and almost no callose was observed in the mature embryo sac in wild-type plants. However, callose deposition was observed in mp1 plants around the synergid, and increased with the development of the embryo sac, and was mainly deposited at the micropylar end. Our results indicate that synergid, central, and antipodal cells, which are surrounded by callose, may degrade owing to lack of nutrition. Callose accumulation around the synergid and at the micropylar end may hinder signals required for the pollen tube to enter the embryo sac, leading to abortion.

  20. Induction of Callose Deposition in Tobacco (Nicotiana tabacum by Bacterial Lipopolysaccharide Pseudomonas syringae pv. tabaci and Pseudomonas syringae pv. glycinea

    Directory of Open Access Journals (Sweden)

    Pipit Marianingsih

    2014-12-01

    Full Text Available Lipopolysaccharide (LPS is a major component of outer-membrane gram-negative bacteria, and it can act as a Pathogen-Associated Molecular Pattern (PAMP for perception of pathogens by plants. LPS can be recognized by plants, triggering certain plant defense-related responses, including callose deposition. This study investigated induction of callose deposition by bacterial LPS in tobacco. Tobacco leaves were infiltrated with 400 μg/mL and 800 μg/mL LPS extracted from Pseudomonas syringae pv. tabaci (Pta and Pseudomonas syringae pv. glycinea (Pgl and incubated for 24 h or 48 h. To detect callose deposition, tobacco leaves were cleared in lactophenol solution, stained with aniline blue, and visualized by fluorescence microscopy. Results showed that LPS from Pgl induced more callose deposition in tobacco leaves than did that from Pta. In addition, a Pearson correlation test revealed that incubation period was the most significant factor in callose deposition, followed by the type of LPS bacteria. However, LPS concentration was not significantly corelated to callose deposition in tobacco leaves.

  1. Relation of callosal structure to cognitive abilities in temporal lobe epilepsy

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    Christine eSchneider

    2014-02-01

    Full Text Available The main objective of this paper is to analyse the influence of mesial temporal lobe epilepsy (TLE on the morphology of the corpus callosum (CC and its relation to cognitive abilities. More specifically, we investigated correlations between intellectual abilities and callosal morphology, while additionally exploring the modulating impact of (a side of seizure onset (b age of disease onset.For this reason a large representative sample of patients with hippocampal sclerosis (n=79; 35 males; 44 females; age: 18-63 years with disease onset ranging from 0 to 50 years of age, and consisting of 46 left and 33 right TLE patients was recruited. Intelligence was measured using the Wechsler Adult Intelligence Scale Revised (WAIS-R.To get localizations of correlations with high anatomic precision, callosal morphology was examined using computational mesh-based modeling methods, applied to anatomical brain MRI scans.Intellectual performance was positively associated with callosal thickness in anterior and midcallosal callosal regions, with anterior parts being slightly more affected by age of disease onset and side of seizure onset than posterior parts. Earlier age at onset of epilepsy was associated with lower thickness in anterior and midcallosal regions. In addition, laterality of seizure onset had a significant influence on anterior CC morphology, with left hemispheric origin having stronger effects.We found that in TLE, anterior and midcallosal CC morphology are related to cognitive performance. The findings support recent findings of detrimental effects of early onset mTLE on anterior brain regions and of a distinct effect particularly of left TLE on frontal lobe functioning and structure. The causal nature of the relationship remains an open question, i.e., whether CC morphology impacts IQ development or whether IQ development impacts CC morphology, or both.

  2. Induction of embryogenesis in Brassica napus microspores produces a callosic subintinal layer and abnormal cell walls with altered levels of callose and cellulose

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    Veronica eParra-Vega

    2015-11-01

    Full Text Available The induction of microspore embryogenesis produces dramatic changes in different aspects of the cell physiology and structure. Changes at the cell wall level are among the most intriguing and poorly understood. In this work, we used high pressure freezing and freeze substitution, immunolocalization, confocal and electron microscopy to analyze the structure and composition of the first cell walls formed during conventional Brassica napus microspore embryogenesis, and in cultures treated to alter the intracellular Ca2+ levels. Our results revealed that one of the first signs of embryogenic commitment is the formation of a callose-rich, cellulose-deficient layer beneath the intine (the subintinal layer, and of irregular, incomplete cell walls. In these events, Ca2+ may have a role. We propose that abnormal cell walls are due to a massive callose synthesis and deposition of excreted cytoplasmic material, and the parallel inhibition of cellulose synthesis. These features were absent in pollen-like structures and in microspore-derived embryos, few days after the end of the heat shock, where abnormal cell walls were no longer produced. Together, our results provide an explanation to a series of relevant aspects of microspore embryogenesis including the role of Ca2+ and the occurrence of abnormal cell walls. In addition, our discovery may be the explanation to why nuclear fusions take place during microspore embryogenesis.

  3. Activity-Dependent Callosal Axon Projections in Neonatal Mouse Cerebral Cortex

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    Yoshiaki Tagawa

    2012-01-01

    Full Text Available Callosal axon projections are among the major long-range axonal projections in the mammalian brain. They are formed during the prenatal and early postnatal periods in the mouse, and their development relies on both activity-independent and -dependent mechanisms. In this paper, we review recent findings about the roles of neuronal activity in callosal axon projections. In addition to the well-documented role of sensory-driven neuronal activity, recent studies using in utero electroporation demonstrated an essential role of spontaneous neuronal activity generated in neonatal cortical circuits. Both presynaptic and postsynaptic neuronal activities are critically involved in the axon development. Studies have begun to reveal intracellular signaling pathway which works downstream of neuronal activity. We also review several distinct patterns of neuronal activity observed in the developing cerebral cortex, which might play roles in activity-dependent circuit construction. Such neuronal activity during the neonatal period can be disrupted by genetic factors, such as mutations in ion channels. It has been speculated that abnormal activity caused by such factors may affect activity-dependent circuit construction, leading to some developmental disorders. We discuss a possibility that genetic mutation in ion channels may impair callosal axon projections through an activity-dependent mechanism.

  4. What is the role of the corpus callosum in intermanual transfer of motor skills? A study of three cases with callosal pathology

    NARCIS (Netherlands)

    Thut, G; Halsband, U; Regard, M; Mayer, E; Leenders, KL; Landis, T

    Intermanual transfer for a skilled motor task was studied in two patients with total callosal agenesis, and one with an acquired partial callosal lesion and clinical evidence for disturbed transfer of motor signals. Patients had to draw meaningless figures with one upper extremity (original

  5. Developmental evolution of flowering plant pollen tube cell walls: callose synthase (CalS gene expression patterns

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    Abercrombie Jason M

    2011-07-01

    Full Text Available Abstract Background A number of innovations underlie the origin of rapid reproductive cycles in angiosperms. A critical early step involved the modification of an ancestrally short and slow-growing pollen tube for faster and longer distance transport of sperm to egg. Associated with this shift are the predominantly callose (1,3-β-glucan walls and septae (callose plugs of angiosperm pollen tubes. Callose synthesis is mediated by callose synthase (CalS. Of 12 CalS gene family members in Arabidopsis, only one (CalS5 has been directly linked to pollen tube callose. CalS5 orthologues are present in several monocot and eudicot genomes, but little is known about the evolutionary origin of CalS5 or what its ancestral function may have been. Results We investigated expression of CalS in pollen and pollen tubes of selected non-flowering seed plants (gymnosperms and angiosperms within lineages that diverged below the monocot/eudicot node. First, we determined the nearly full length coding sequence of a CalS5 orthologue from Cabomba caroliniana (CcCalS5 (Nymphaeales. Semi-quantitative RT-PCR demonstrated low CcCalS5 expression within several vegetative tissues, but strong expression in mature pollen. CalS transcripts were detected in pollen tubes of several species within Nymphaeales and Austrobaileyales, and comparative analyses with a phylogenetically diverse group of sequenced genomes indicated homology to CalS5. We also report in silico evidence of a putative CalS5 orthologue from Amborella. Among gymnosperms, CalS5 transcripts were recovered from germinating pollen of Gnetum and Ginkgo, but a novel CalS paralog was instead amplified from germinating pollen of Pinus taeda. Conclusion The finding that CalS5 is the predominant callose synthase in pollen tubes of both early-diverging and model system angiosperms is an indicator of the homology of their novel callosic pollen tube walls and callose plugs. The data suggest that CalS5 had transient expression

  6. Characterization and partial purification of beta-1,3-D-glucan (callose) synthase from barley (Hordeum vulgare) leaves

    DEFF Research Database (Denmark)

    Pedersen, L.H.; Jacobsen, S.; Hejgaard, J.

    1993-01-01

    The plasma membrane bound beta-1,3-D-glucan (callose) synthase. assumed to be involved in the resistance to the powdery mildew fungus (Erysiphe graminis f.sp. hordei), was partially purified from a microsomal fraction of green barley leaves (Hordeum vulgare L.). Plasma membranes were enriched...... was inhibited by UDP and uridine 5' triphosphate (UTP). Glucanase digestion of the in vitro product showed that it was a beta-1,3-linked polysaccharide. Two different procedures were used for further enrichment of polypeptides involved in callose synthase activity. Sucrose gradient centrifugation...

  7. Callose Synthase Family Genes Involved in the Grapevine Defense Response to Downy Mildew Disease.

    Science.gov (United States)

    Yu, Ying; Jiao, Li; Fu, Shufang; Yin, Ling; Zhang, Yali; Lu, Jiang

    2016-01-01

    The deposition of callose is a common plant defense response to intruding pathogens and part of the plant's innate immunity. In this study, eight grapevine callose synthase (CalS) genes were identified and characterized. To investigate biological function of CalS in grapevine against the infection of Plasmopara viticola, expression patterns of grapevine CalS family genes were analyzed among resistant/susceptible cultivars. After P. viticola infection, expression of CalS1, 3, 7, 8, 9, 10, and 11 were significantly modified among the grapevine cultivars. For example, the expression of CalS1 and CalS10 were greatly increased in downy mildew (DM)-immune Muscadinia rotundifolia 'Carlos' and 'Noble'. Transient expression assay with promoters of the CalS1 and CalS10 genes confirmed that they were regulated by the oomycete pathogen P. viticola. CalS1 promoter activity was also significantly up-regulated by ABA in DM-immune M. rotundifolia 'Noble', but down-regulated in DM-susceptible Vitis vinifera 'Chardonnay'. The CalS1 promoter, however, was also down-regulated by GA in 'Chardonnay', but not affected in 'Noble'. The promoter activity of CalS10 was significantly up-regulated by GA in 'Chardonnay', but not regulated by ABA at all. It is proposed that CalS1 and CalS10 were involved in grapevine defense against DM disease.

  8. Pathology of callosal damage in ALS: An ex-vivo, 7 T diffusion tensor MRI study

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    Agustin M. Cardenas

    2017-01-01

    Conclusion: Reduced FA of the corpus callosum in ALS results from complex changes in tissue microstructure. Callosal segments with reduced FA had large numbers of microglia-macrophages in addition to loss of myelinated axons and astrogliosis. Microglial inflammation contributed to reduced FA in ALS, and may contribute to a pro-inflammatory state, but further work is needed to determine their role.

  9. A new sign of callosal disconnection syndrome: agonistic dyspraxia. A case study.

    Science.gov (United States)

    Lavados, Manuel; Carrasco, Ximena; Peña, Marcela; Zaidel, Eran; Zaidel, Dahlia; Aboitiz, Francisco

    2002-01-01

    We report a patient with callosal haemorrhage and no extracallosal involvement who developed a unique form of intermanual conflict. In the acute phase the patient showed a mild speech disturbance and right hemiparesis, and in her right hand, a grasp reflex and compulsive manipulation of tools, all attributable to transient frontal involvement. In the chronic phase there was intermanual conflict occasionally associated with the sensation of a second left hand. The patient also presented a sign consisting of compulsive, automatic execution of orders by one hand (the left or the right) when the patient was specifically asked to perform the movement with the other hand (the right or the left, respectively). There was no left-right confusion in this patient. We call this condition agonistic dyspraxia. In contrast with diagonistic dyspraxia, this consists of the agonistic behaviour of the other hand under conditions in which the hand that has been instructed to respond cannot execute the request.

  10. Callosal disconnection syndrome after corpus callosum infarct: a diffusion tensor tractography study.

    Science.gov (United States)

    Jang, Sung Ho; Lee, Jun; Yeo, Sang Seok; Chang, Min Cheol

    2013-10-01

    We report a patient who presented with callosal disconnection syndrome (CDS) and fiber disconnection on diffusion tensor tractography (DTT) after an infarct of the corpus callosum (CC). A 72-year-old woman presented with manifestations of CDS, including frontal alien hand syndrome (AHS), left agraphia, right hemiparesis, right somatosensory deficit, left neglect, and impaired visual recognition. DTT was performed for the evaluation of CC fibers, followed by comparison with DTT findings of normal subjects. DTT of the normal subject revealed bilateral extension of CC fibers to the frontal, parietal, and occipitotemporal cortices. By contrast, CC fibers of the patient revealed extensive disruption, with the exception of CC fibers passing through the anterior genu and the posterior splenium. The extensive disruption of CC fibers appears to explain the patient's various CDS symptoms. In brief, DTT could be useful for detection of CC lesions in patients with CDS. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  11. Unaffected twins discordant for affective disorders show changes in anterior callosal white matter microstructure

    DEFF Research Database (Denmark)

    Macoveanu, J; Vinberg, M; Madsen, K.

    2016-01-01

    tracts, that is, cingulum bundle, uncinate fasciculus, anterior limb of the internal capsule, and corpus callosum, that facilitate the communication between brain regions implicated in affective disorders. METHOD: Eighty-nine healthy mono- or dizygotic twins with a co-twin diagnosed with MDD or BD (high...... communication between left and right frontal regions critically involved in mood regulation. Reduced anterior callosal FA may act as a vulnerability marker for affective disorders in individuals at familial risk.......OBJECTIVE: The neurobiological mechanisms mediating an increased risk to develop affective disorders remain poorly understood. In a group of individuals with a family history of major depressive (MDD) or bipolar disorder (BD), we investigated the microstructural properties of white matter fiber...

  12. Evolutionary history of callose synthases in terrestrial plants with emphasis on proteins involved in male gametophyte development.

    Directory of Open Access Journals (Sweden)

    Lenka Záveská Drábková

    Full Text Available Callose is a plant-specific polysaccharide (β-1,3-glucan playing an important role in angiosperms in many developmental processes and responses to biotic and abiotic stresses. Callose is synthesised at the plasma membrane of plant cells by callose synthase (CalS and, among others, represents the main polysaccharide in the callose wall surrounding the tetrads of developing microspores and in the growing pollen tube wall. CalS proteins involvement in spore development is a plesiomorphic feature of terrestrial plants, but very little is known about their evolutionary origin and relationships amongst the members of this protein family. We performed thorough comparative analyses of callose synthase family proteins from major plant lineages to determine their evolutionary history across the plant kingdom. A total of 1211 candidate CalS sequences were identified and compared amongst diverse taxonomic groups of plants, from bryophytes to angiosperms. Phylogenetic analyses identified six main clades of CalS proteins and suggested duplications during the evolution of specialised functions. Twelve family members had previously been identified in Arabidopsis thaliana. We focused on five CalS subfamilies directly linked to pollen function and found that proteins expressed in pollen evolved twice. CalS9/10 and CalS11/12 formed well-defined clades, whereas pollen-specific CalS5 was found within subfamilies that mostly did not express in mature pollen vegetative cell, although were found in sperm cells. Expression of five out of seven mature pollen-expressed CalS genes was affected by mutations in bzip transcription factors. Only three subfamilies, CalS5, CalS10, and CalS11, however, formed monophyletic, mostly conserved clades. The pairs CalS9/CalS10, CalS11/CalS12 and CalS3 may have diverged after angiosperms diversified from lycophytes and bryophytes. Our analysis of fully sequenced plant proteins identified new evolutionary lineages of callose synthase

  13. Evolutionary history of callose synthases in terrestrial plants with emphasis on proteins involved in male gametophyte development.

    Science.gov (United States)

    Záveská Drábková, Lenka; Honys, David

    2017-01-01

    Callose is a plant-specific polysaccharide (β-1,3-glucan) playing an important role in angiosperms in many developmental processes and responses to biotic and abiotic stresses. Callose is synthesised at the plasma membrane of plant cells by callose synthase (CalS) and, among others, represents the main polysaccharide in the callose wall surrounding the tetrads of developing microspores and in the growing pollen tube wall. CalS proteins involvement in spore development is a plesiomorphic feature of terrestrial plants, but very little is known about their evolutionary origin and relationships amongst the members of this protein family. We performed thorough comparative analyses of callose synthase family proteins from major plant lineages to determine their evolutionary history across the plant kingdom. A total of 1211 candidate CalS sequences were identified and compared amongst diverse taxonomic groups of plants, from bryophytes to angiosperms. Phylogenetic analyses identified six main clades of CalS proteins and suggested duplications during the evolution of specialised functions. Twelve family members had previously been identified in Arabidopsis thaliana. We focused on five CalS subfamilies directly linked to pollen function and found that proteins expressed in pollen evolved twice. CalS9/10 and CalS11/12 formed well-defined clades, whereas pollen-specific CalS5 was found within subfamilies that mostly did not express in mature pollen vegetative cell, although were found in sperm cells. Expression of five out of seven mature pollen-expressed CalS genes was affected by mutations in bzip transcription factors. Only three subfamilies, CalS5, CalS10, and CalS11, however, formed monophyletic, mostly conserved clades. The pairs CalS9/CalS10, CalS11/CalS12 and CalS3 may have diverged after angiosperms diversified from lycophytes and bryophytes. Our analysis of fully sequenced plant proteins identified new evolutionary lineages of callose synthase subfamilies and has

  14. Transgenic Arabidopsis thaliana plants expressing a β-1,3-glucanase from sweet sorghum (Sorghum bicolor L.) show reduced callose deposition and increased tolerance to aluminium toxicity.

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    Zhang, Hui; Shi, Wu Liang; You, Jiang Feng; Bian, Ming Di; Qin, Xiao Mei; Yu, Hui; Liu, Qing; Ryan, Peter R; Yang, Zhen Ming

    2015-06-01

    Seventy-one cultivars of sweet sorghum (Sorghum bicolor L.) were screened for aluminium (Al) tolerance by measuring relative root growth (RRG). Two contrasting cultivars, ROMA (Al tolerant) and POTCHETSTRM (Al sensitive), were selected to study shorter term responses to Al stress. POTCHETSTRM had higher callose synthase activity, lower β-1,3-glucanase activity and more callose deposition in the root apices during Al treatment compared with ROMA. We monitored the expression of 12 genes involved in callose synthesis and degradation and found that one of these, SbGlu1 (Sb03g045630.1), which encodes a β-1,3-glucanase enzyme, best explained the contrasting deposition of callose in ROMA and POTCHETSTRM during Al treatment. Full-length cDNAs of SbGlu1 was prepared from ROMA and POTCHETSTRM and expressed in Arabidopsis thaliana using the constitutive cauliflower mosaic virus (CaMV) 35S promoter. Independent transgenic lines displayed significantly greater Al tolerance than wild-type plants and vector-only controls. This phenotype was associated with greater total β-1,3-glucanase activity, less Al accumulation and reduced callose deposition in the roots. These results suggest that callose production is not just an early indicator of Al stress in plants but likely to be part of the toxicity pathway that leads to the inhibition of root growth. © 2014 John Wiley & Sons Ltd.

  15. Generalized epilepsy syndromes and callosal thickness: Differential effects between patients with juvenile myoclonic epilepsy and those with generalized tonic-clonic seizures alone.

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    Anastasopoulou, Stavroula; Kurth, Florian; Luders, Eileen; Savic, Ivanka

    2017-01-01

    The definition of two well-studied genetic generalized epilepsy syndromes (GGE) - juvenile myoclonic epilepsy (JME) and epilepsy with generalized tonic-clonic seizures alone (GTCS) - suggests the absence of structural cerebral abnormalities. Nevertheless, there are various reports of such abnormalities (especially in JME), where effects mainly occur within thalamus and mesial prefrontal regions. This raises the question of whether JME is particularly linked to midline structure abnormalities, which may also involve the corpus callosum. We studied callosal morphology in a well-matched sample of 22 JME patients, 15 GTCS patients, and 42 controls (CTL) for all of whom we obtained T1-weighted data on a 3T MRI scanner. More specifically, we measured callosal thickness at 100 equidistant points across the callosal surface, and subsequently compared the three groups (JME, GTCS, and CTL) against each other. Significant differences between JME patients and controls were observed within the callosal genu, anterior midbody, and isthmus, with thinner regions in JME patients. There were no significant differences between GTCS patients and controls, and also not between JME patients and GTCS patients. The present outcomes point to callosal abnormalities in JME patients suggesting an impairment of interhemisperic communication between prefrontal, motor, parietal and temporal cortices. These findings further support the notion that structural aberrations are present and differentiated across GGE syndromes, with significant callosal deviations from normality in JME. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Dissociation between distal and proximal left limb agraphia and agraphesthesia in a patient with a callosal disconnection syndrome.

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    Bachoud-Lévi, A C; Ergis, A M; Cesaro, P; Degos, J D

    2000-06-01

    A few neuropsychological studies have suggested the existence of bilateral hemispheric representations for the proximal parts of the limbs in humans. We report the case of a patient who presented with a callosal disconnection syndrome, which at a later stage of disease became restricted to left agraphia, left agraphesthesia and left auditory extinction. The anomic character of the agraphesthesia was demonstrated. Tactile naming was normal, which allows us to conclude that separate callosal pathways related to the left language areas transmit information for graphesthesia and tactile naming. Agraphia and agraphesthesia were not observed when the proximal part of the left upper limb was utilized. These observations support the conclusion that writing and graphesthesia with the proximal part of the limb can be mediated by the ipsilateral cortex.

  17. Hexanoic Acid Treatment Prevents Systemic MNSV Movement in Cucumis melo Plants by Priming Callose Deposition Correlating SA and OPDA Accumulation

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    Emma Fernández-Crespo; Navarro, Jose A.; Marta Serra-Soriano; Iván Finiti; Pilar García-Agustín; Vicente Pallás; Carmen González-Bosch

    2017-01-01

    Unlike fungal and bacterial diseases, no direct method is available to control viral diseases. The use of resistance-inducing compounds can be an alternative strategy for plant viruses. Here we studied the basal response of melon to Melon necrotic spot virus (MNSV) and demonstrated the efficacy of hexanoic acid (Hx) priming, which prevents the virus from systemically spreading. We analysed callose deposition and the hormonal profile and gene expression at the whole plant level. This allowed u...

  18. Correlation between pollen aperture pattern and callose deposition in late tetrad stage in three species producing atypical pollen grains.

    Science.gov (United States)

    Albert, Béatrice; Ressayre, Adrienne; Nadot, Sophie

    2011-02-01

    Pollen grains of flowering plants display a fascinating diversity of forms, in spite of their minute size. The observed diversity is determined by the developmental mechanisms implicated in the establishment of pollen morphological features. Pollen grains are generally surrounded by an extremely resistant wall interrupted in places by apertures that play a key role in reproduction, being the places at which pollen tube growth is initiated. Aperture shape, number, and position are determined during microsporogenesis (male meiosis), the earliest step in pollen ontogeny. We investigate in detail the unfolding of microsporogenesis in three species that present uncommon aperture pattern (i.e., disulculate in Calycanthus floridus [Calycanthaceae, magnoliids], tetraporate in Hohenbergia stellata [Bromeliaceae, monocots], and monoporate in Typha latifolia [Typhaceae, monocots]). We performed a comparative analysis of microsporogenesis and aperture distribution within tetrads in these species with contrasting aperture arrangements. This was done using aniline blue coloration and UV light microscope observations. KEYS RESULTS: We show that aperture localization and features of callose deposition on intersporal walls produced during cytokinesis coincide in all three species examined. Such a correlation suggests that patterns of callose deposition are strongly involved in determining aperture localization. In flowering plants, patterns of male meiosis and especially callose deposition following meiosis may be implicated in the diversity of pollen aperture patterns.

  19. Hexanoic Acid Treatment Prevents Systemic MNSV Movement in Cucumis melo Plants by Priming Callose Deposition Correlating SA and OPDA Accumulation

    Directory of Open Access Journals (Sweden)

    Emma Fernández-Crespo

    2017-10-01

    Full Text Available Unlike fungal and bacterial diseases, no direct method is available to control viral diseases. The use of resistance-inducing compounds can be an alternative strategy for plant viruses. Here we studied the basal response of melon to Melon necrotic spot virus (MNSV and demonstrated the efficacy of hexanoic acid (Hx priming, which prevents the virus from systemically spreading. We analysed callose deposition and the hormonal profile and gene expression at the whole plant level. This allowed us to determine hormonal homeostasis in the melon roots, cotyledons, hypocotyls, stems and leaves involved in basal and hexanoic acid-induced resistance (Hx-IR to MNSV. Our data indicate important roles of salicylic acid (SA, 12-oxo-phytodienoic acid (OPDA, jasmonic-isoleucine, and ferulic acid in both responses to MNSV. The hormonal and metabolites balance, depending on the time and location associated with basal and Hx-IR, demonstrated the reprogramming of plant metabolism in MNSV-inoculated plants. The treatment with both SA and OPDA prior to virus infection significantly reduced MNSV systemic movement by inducing callose deposition. This demonstrates their relevance in Hx-IR against MNSV and a high correlation with callose deposition. Our data also provide valuable evidence to unravel priming mechanisms by natural compounds.

  20. Deafferentation-Induced Plasticity of Visual Callosal Connections: Predicting Critical Periods and Analyzing Cortical Abnormalities Using Diffusion Tensor Imaging

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    Jaime F. Olavarria

    2012-01-01

    Full Text Available Callosal connections form elaborate patterns that bear close association with striate and extrastriate visual areas. Although it is known that retinal input is required for normal callosal development, there is little information regarding the period during which the retina is critically needed and whether this period correlates with the same developmental stage across species. Here we review the timing of this critical period, identified in rodents and ferrets by the effects that timed enucleations have on mature callosal connections, and compare it to other developmental milestones in these species. Subsequently, we compare these events to diffusion tensor imaging (DTI measurements of water diffusion anisotropy within developing cerebral cortex. We observed that the relationship between the timing of the critical period and the DTI-characterized developmental trajectory is strikingly similar in rodents and ferrets, which opens the possibility of using cortical DTI trajectories for predicting the critical period in species, such as humans, in which this period likely occurs prenatally. Last, we discuss the potential of utilizing DTI to distinguish normal from abnormal cerebral cortical development, both within the context of aberrant connectivity induced by early retinal deafferentation, and more generally as a potential tool for detecting abnormalities associated with neurodevelopmental disorders.

  1. Is Disturbed Transfer of Learning in Callosal Agenesis due to a Disconnection Syndrome?

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    T. Imamura

    1994-01-01

    Full Text Available Disturbed intermanual transfer of tactile learning in callosal agenesis has been interpreted as a sign of disconnection syndrome. We observed this sign in one of four acallosal patients with a conventional form-board task, and tried to elucidate the nature of the deficit. The form-board performance of the patient with disturbed transfer of learning totally depended on motor skill, while the other acallosals and normal controls executed the task based on spatial and somesthetic information. All acallosals and normals, however, failed to show transfer of learning with another tactile task which needed motor skill but not spatial-somesthetic information. These findings suggest that the task-performing strategies in form-board learning change the state of interhemispheric transfer. Unimanual learning effect is transferred if spatial-somesthetic information is acquired in the process of learning, but is not transferred if motor skill is the exclusive content of learning. We conclude that disturbed “transfer” of learning in some acallosals is not a true disconnection sign. It should be attributed to a lack of appropriate strategy, as a result of ineffective problem solving in tactile tasks.

  2. Mid-callosal plane determination using preferred directions from diffusion tensor images

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    Costa, André L.; Rittner, Letícia; Lotufo, Roberto A.; Appenzeller, Simone

    2015-03-01

    The corpus callosum is the major brain structure responsible for inter{hemispheric communication between neurons. Many studies seek to relate corpus callosum attributes to patient characteristics, cerebral diseases and psychological disorders. Most of those studies rely on 2D analysis of the corpus callosum in the mid-sagittal plane. However, it is common to find conflicting results among studies, once many ignore methodological issues and define the mid-sagittal plane based on precary or invalid criteria with respect to the corpus callosum. In this work we propose a novel method to determine the mid-callosal plane using the corpus callosum internal preferred diffusion directions obtained from diffusion tensor images. This plane is analogous to the mid-sagittal plane, but intended to serve exclusively as the corpus callosum reference. Our method elucidates the great potential the directional information of the corpus callosum fibers have to indicate its own referential. Results from experiments with five image pairs from distinct subjects, obtained under the same conditions, demonstrate the method effectiveness to find the corpus callosum symmetric axis relative to the axial plane.

  3. Paralinguistic processing in children with callosal agenesis: emergence of neurolinguistic deficits.

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    Brown, Warren S; Symingtion, Melissa; VanLancker-Sidtis, Diana; Dietrich, Rosalind; Paul, Lynn K

    2005-05-01

    Recent research revealed impaired processing of both nonliteral meaning and affective prosody in adults with agenesis of the corpus callosum (ACC) and normal intelligence. Since normal children have incomplete myelination of the corpus callosum, it was hypothesized that paralanguage deficits in children with ACC would be less apparent relative to their peers. The Familiar and Novel Language Comprehension Test (FANL-C) and Prosody Test were given to 18 children with ACC and normal intelligence and 17 controls matched for age (7-13 years), education, and IQ (83-122). When controlling for age, children with ACC were significantly poorer in comprehension of the precise meaning of both literal and nonliteral items on the FANL-C. Adults with ACC had previously been shown to have difficulty only on nonliteral items. The effect size for nonliteral comprehension in children with ACC was smaller than that seen in adults. There was only a trend for the child ACC group to perform worse on the recognition of affective prosody. Thus, while deficits in paralinguistic processing were apparent, children with ACC were not as clearly different from age peers as adults, and were equally deficient at comprehending literal and nonliteral expressions. The differences in results between adults and children with ACC are thought to reflect incomplete callosal development in normal children, and the importance of the corpus callosum in the early stages of the development of the ability to process literal language.

  4. [Acute disseminated encephalomyelitis following influenza vaccination: report of a case with callosal disconnection syndrome].

    Science.gov (United States)

    Arai, Motomi; Takagi, Daisuke; Nagao, Ryosuke

    2014-01-01

    We present a case of callosal disconnection syndrome as a rare manifestation of acute disseminated encephalomyelitis (ADEM). A dextral 48-year-old Japanese woman received trivalent inactivated influenza vaccine in mid-November 2011. Twenty days later, she was found to be in a daze. Subsequently, she developed abnormal behavior and gait disturbance, and she was disoriented regarding time and place. Nystagmus and abnormal ocular movements were absent. Upper limb power was normal, whereas her lower limbs were mildly weak. Tendon reflexes were normally evoked without pathological reflexes. There was no sensory impairment. Serum CRP levels were slightly elevated; other routine laboratory tests, thyroid functions, and vitamin B1 levels were within the normal range. Cerebrospinal fluid examination revealed that it was acellular with a protein level of 54 mg/dl and high myelin basic protein level. Fluid-attenuated inversion recovery MR images revealed a large hyperintense lesion in the corpus callosum, but the lower part of the splenium was spared. Flow voids were observed in the pericallosal arteries. She was diagnosed with post-vaccination ADEM and vigorously treated with an intravenous infusion of methylprednisolone (1 g/day for 6 days) and immunoglobulin (1.2 g/kg). Gait disturbance and disorientation rapidly improved; however, tactile anomia, ideomotor apraxia, ideational apraxia, and agraphia of the left hand were present one month after onset. She had no aphasia or alexia.Interestingly, the patient's left unilateral agraphia was more prominent in kana than kanji (an article in Japanese text) for polysyllabic words, whereas she could write kana characters to dictation. Changes in the sequential order of kana characters within a word were observed. These findings were similar to those observed in pure agraphia associated with lesions in the posterior part of the left middle frontal gyrus. Thus, an interhemispheric mechanism is probably involved in the selection and

  5. Functional expansion of sensorimotor representation and structural reorganization of callosal connections in lower limb amputees.

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    Simões, Elington L; Bramati, Ivanei; Rodrigues, Erika; Franzoi, Ana; Moll, Jorge; Lent, Roberto; Tovar-Moll, Fernanda

    2012-02-29

    Previous studies have indicated that amputation or deafferentation of a limb induces functional changes in sensory (S1) and motor (M1) cortices, related to phantom limb pain. However, the extent of cortical reorganization after lower limb amputation in patients with nonpainful phantom phenomena remains uncertain. In this study, we combined functional magnetic resonance (fMRI) and diffusion tensor imaging (DTI) to investigate the existence and extent of cortical and callosal plasticity in these subjects. Nine "painless" patients with lower limb amputation and nine control subjects (sex- and age-matched) underwent a 3-T MRI protocol, including fMRI with somatosensory stimulation. In amputees, we observed an expansion of activation maps of the stump in S1 and M1 of the deafferented hemisphere, spreading to neighboring regions that represent the trunk and upper limbs. We also observed that tactile stimulation of the intact foot in amputees induced a greater activation of ipsilateral S1, when compared with controls. These results demonstrate a functional remapping of S1 in lower limb amputees. However, in contrast to previous studies, these neuroplastic changes do not appear to be dependent on phantom pain but do also occur in those who reported only the presence of phantom sensation without pain. In addition, our findings indicate that amputation of a limb also induces changes in the cortical representation of the intact limb. Finally, DTI analysis showed structural changes in the corpus callosum of amputees, compatible with the hypothesis that phantom sensations may depend on inhibitory release in the sensorimotor cortex.

  6. Normal centrolineal myelination of the callosal splenium reflects the development of the cortical origin and size of its commissural fibers

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    Whitehead, Matthew T. [University of Tennessee Health Science Center, Department of Radiology, Memphis, TN (United States); Le Bonheur Children' s Hospital, Le Bonheur Neuroscience Institute, Memphis, TN (United States); Children' s National Medical Center, Department of Radiology, Washington, DC (United States); Raju, Anand; Choudhri, Asim F. [University of Tennessee Health Science Center, Department of Radiology, Memphis, TN (United States); Le Bonheur Children' s Hospital, Le Bonheur Neuroscience Institute, Memphis, TN (United States)

    2014-04-15

    Commissural white matter fibers comprising the callosal splenium are diverse. Subsections of the splenium myelinate at different times, in a centrolineal manner. The aims of this study are to depict the normal callosal splenium myelination pattern and to distinguish the transient age-related mid splenium hypointensity from pathology. We reviewed 131 consecutive brain MRIs in patients between ages 3 and 6 months from a single academic children's hospital. Patients that were preterm, hydrocephalic, and/or had volume loss were excluded. Fifty total MR exams that included T1-weighted MR imaging (T1WI), T2-weighted MR imaging (T2WI), and diffusion tensor imaging (DTI) were reviewed. Regions of callosal splenium myelination manifested by T1 and T2 shortening were evaluated. Tractography was performed with seeds placed over the posterior, mid, and anterior splenium to define the origin, destination, and course of traversing fibers. Splenium signal varied significantly from 3 to 6 months, with distinct age-related trends. On T1WI, the splenium was hypointense at 3 months (12/13), centrally hypointense/peripherally hyperintense at 4 months (15/16), and hyperintense at 6 months (10/11). Tractography revealed three distinct white matter tract populations: medial occipital (posterior); precuneus, posterior cingulate, and medial temporal (middle); and postcentral gyri (anterior). Specific commissural fiber components of the splenium myelinate at different times. The transient developmental mid splenium hypointensity on T1WI corresponds to tracts from the associative cortex, principally the precuneus. Heterogeneous splenium signal alteration in patients ages 3-6 months is a normal developmental phenomenon that should not be confused with pathologic lesions. (orig.)

  7. Tocopherol deficiency reduces sucrose export from salt-stressed potato leaves independently of oxidative stress and symplastic obstruction by callose

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    Asensi-Fabado, María Amparo; Ammon, Alexandra; Sonnewald, Uwe; Munné-Bosch, Sergi; Voll, Lars M.

    2015-01-01

    Tocopherol cyclase, encoded by the gene SUCROSE EXPORT DEFECTIVE1, catalyses the second step in the synthesis of the antioxidant tocopherol. Depletion of SXD1 activity in maize and potato leaves leads to tocopherol deficiency and a ‘sugar export block’ phenotype that comprises massive starch accumulation and obstruction of plasmodesmata in paraveinal tissue by callose. We grew two transgenic StSXD1:RNAi potato lines with severe tocopherol deficiency under moderate light conditions and subjected them to salt stress. After three weeks of salt exposure, we observed a strongly reduced sugar exudation rate and a lack of starch mobilization in leaves of salt-stressed transgenic plants, but not in wild-type plants. However, callose accumulation in the vasculature declined upon salt stress in all genotypes, indicating that callose plugging of plasmodesmata was not the sole cause of the sugar export block phenotype in tocopherol-deficient leaves. Based on comprehensive gene expression analyses, we propose that enhanced responsiveness of SnRK1 target genes in mesophyll cells and altered redox regulation of phloem loading by SUT1 contribute to the attenuation of sucrose export from salt-stressed SXD:RNAi source leaves. Furthermore, we could not find any indication that elevated oxidative stress may have served as a trigger for the salt-induced carbohydrate phenotype of SXD1:RNAi transgenic plants. In leaves of the SXD1:RNAi plants, sodium accumulation was diminished, while proline accumulation and pools of soluble antioxidants were increased. As supported by phytohormone contents, these differences seem to increase longevity and prevent senescence of SXD:RNAi leaves under salt stress. PMID:25428995

  8. Splitting of the P3 component during dual-task processing in a patient with posterior callosal section.

    Science.gov (United States)

    Hesselmann, Guido; Naccache, Lionel; Cohen, Laurent; Dehaene, Stanislas

    2013-03-01

    When two concurrent sensorimotor tasks have to be performed at a short time interval, the second response is generally delayed at a central decision stage. However, in patients who have undergone full or partial transection of forebrain fibers connecting the two hemispheres (split-brain), independent structures subserving all processing stages should reside in each disconnected hemisphere, thus predicting parallel processing of dual tasks. Surprisingly, this prediction is usually not verified behaviorally. We reasoned that brain imaging with high-density recordings of event-related potentials (ERPs) could clarify the extent and limits of parallel processing in callosal patients. We studied a patient (AC) with posterior callosal section in a lateralized number-comparison task. Behaviorally, the split-brain patient showed robust dual-task interference, superficially similar to the psychological refractory period (PRP) effect in the control group of 14 healthy subjects, but significantly different in important aspects such as slowing of response times in the first task. Analysis of ERPs revealed that the parietal P3 component became split into distinct contralateral components in the patient, and was dramatically reduced for targets in his left visual field. In contrast to the control group, P3 latencies showed minimal to nonexistent postponement related to dual-task processing in the patient. In summary, our findings suggest that the left and right hemisphere networks normally involved in a single distributed "global neuronal workspace" that underlies the generation of the P3 component and serial processing, became strongly decoupled after a posterior callosal lesion. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. MRI in callosal apraxia and agraphia due to a traumatic lesion in the posterior trunk of the corpus callosum

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    Yasumura, Shuichi; Ito, Naoki; Terunuma, Hiroshi; Matsuzaki, Takayuki; Iwabuchi, Reiko

    1987-08-01

    We discussed functional topography of the corpus callosum in a case with ideo-motor apraxia and agraphia of the left hand due to a traumatic callosal hematoma confirmed by MRI. The patient was a 35-year-old right-handed woman with head injury in a traffic accident. On admission she was semi-comatose with left oculomotor palsy and her left upper limb showed a decorticate rigidity by noxious stimuli, however, she became alert within 14 days. X-ray CT showed an abnormal high density area in the posterior part of the trunk of the corpus callosum on admission. MRI (inversion recovery technique) on the 60th hospital day showed a low intensity area extending for about 2 cm posteriorly from the center of the trunk. Sequential neuropsychological examinations for the callosal disconnection syndrome were performed. The patient showed ideo-motor apraxia and agraphia in her left hand only. Her response to verbal commands were all parapraxic except for correct use of a comb and a tooth brush. Her writings with her left hand were those of scrawls due to apraxia. These apraxia and agraphia of the left hand were transient and recovered completely within 80 days of onset. Transient impairement of bimanual coordination movement was also observed. Ataxie optique, callosal pseudoneglect, left hand tactile anomia, difficulty of somesthetic transfer or diagonistic dyspraxia was not observed. Based on the neuropsychological and the MRI findings we suggest that the lesion in the posterior part of the trunk of the corpus callosum is important for causing ideo-motor apraxia and agraphia of the left hand.

  10. Mechanisms Underlying Serotonergic Excitation of Callosal Projection Neurons in the Mouse Medial Prefrontal Cortex

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    Emily K. Stephens

    2018-01-01

    Full Text Available Serotonin (5-HT selectively excites subpopulations of pyramidal neurons in the neocortex via activation of 5-HT2A (2A receptors coupled to Gq subtype G-protein alpha subunits. Gq-mediated excitatory responses have been attributed primarily to suppression of potassium conductances, including those mediated by KV7 potassium channels (i.e., the M-current, or activation of non-specific cation conductances that underlie calcium-dependent afterdepolarizations (ADPs. However, 2A-dependent excitation of cortical neurons has not been extensively studied, and no consensus exists regarding the underlying ionic effector(s involved. In layer 5 of the mouse medial prefrontal cortex, we tested potential mechanisms of serotonergic excitation in commissural/callosal (COM projection neurons, a subpopulation of pyramidal neurons that exhibits 2A-dependent excitation in response to 5-HT. In baseline conditions, 5-HT enhanced the rate of action potential generation in COM neurons experiencing suprathreshold somatic current injection. This serotonergic excitation was occluded by activation of muscarinic acetylcholine (ACh receptors, confirming that 5-HT acts via the same Gq-signaling cascades engaged by ACh. Like ACh, 5-HT promoted the generation of calcium-dependent ADPs following spike trains. However, calcium was not necessary for serotonergic excitation, as responses to 5-HT were enhanced (by >100%, rather than reduced, by chelation of intracellular calcium with 10 mM BAPTA. This suggests intracellular calcium negatively regulates additional ionic conductances gated by 2A receptors. Removal of extracellular calcium had no effect when intracellular calcium signaling was intact, but suppressed 5-HT response amplitudes, by about 50%, when BAPTA was included in patch pipettes. This suggests that 2A excitation involves activation of a non-specific cation conductance that is both calcium-sensitive and calcium-permeable. M-current suppression was found to be a third

  11. Intracranial Hemorrhage in the Corpus Callosum Presenting as Callosal Disconnection Syndrome: FDG-PET and Tractography: A Case Report.

    Science.gov (United States)

    Kim, In Hwan; Lee, Soyoung; Lee, Chang-Young; Lee, Dong Gyu

    2014-12-01

    We report the findings of (18)F-fluorodeoxyglocese positron emission tomography (FDG-PET) and diffusion tensor tractography (DTT) in a right-handed patient presenting with callosal disconnection syndrome, including alien hand syndrome, after an anterior communicating artery aneurysmal rupture. The 49-year-old patient had right hemiparesis and unintended movement of the right hand during action of the left hand. A brain magnetic resonance imaging revealed lesions in the upper part of the genu and body in the corpus callosum as well as hemorrhage in the inter-hemispheric fissure. We observed extensive disruption of corpus callosum fibers in the upper genu and trunk by DTT for the evaluation of inter-hemispheric connection. FDG-PET revealed severe hypometabolism in the left cerebral hemisphere, including basal ganglia and thalamus, and hypermetabolism in the right cerebral hemisphere. Based on findings of FDG-PET and DTT, the callosal disconnection syndrome presented in the patient could be the result of loss of transcallosal inhibition in the contralateral hemisphere.

  12. Association between preoperative pain intensity of MTP joint callosities of the lesser toes and fore-mid-hindfoot deformities in rheumatoid arthritis cases.

    Science.gov (United States)

    Hirao, Makoto; Ebina, Kosuke; Shi, Kenrin; Tomita, Tetsuya; Noguchi, Takaaki; Tsuboi, Hideki; Hashimoto, Jun; Yoshikawa, Hideki

    2017-01-01

    To determine whether preoperative pain intensity in callosities of the lesser toe metatarsopharangeal (MTP) joint was associated with the grade of fore-mid-hindfoot deformities, because rheumatoid arthritis (RA) foot deformity includes the whole part of foot, and curiously differences between cases in the pain intensity of MTP joint callosities are often observed. We evaluated 24 feet that had undergone forefoot surgery [August, 2014 - December, 2015] for painful lesser toe MTP joint deformity (callosities) in RA cases. A preoperative self-administered foot evaluation questionnaire (SAFE-Q) and pressure distribution information for foot function were also investigated. X-rays of the whole lower extremities and foot at weight-bearing were used to check fore-mid-hindfoot deformities. Group M (mild) [n = 9] included patients with the pain visual analog scale (VAS) less than 40 mm, while group S (severe) [n = 15] included patients whose VAS was over 40 mm. Group M showed stronger hindfoot valgus and pronated (abducted) deformity, and group M showed higher pressure on the first MTP joint compared with group S. These observations reconfirm that hindfoot valgus deformity and/or pronated (abducted) foot deformity affects the forefoot loading distribution, subsequently the pain of callosities in lesser toe MTP joints could be decreased.

  13. Anisotropy of callosal motor fibers in combination with transcranial magnetic stimulation in the course of motor development.

    Science.gov (United States)

    Koerte, Inga; Heinen, Florian; Fuchs, Teresa; Laubender, Ruediger P; Pomschar, Andreas; Stahl, Robert; Berweck, Steffen; Winkler, Peter; Hufschmidt, Andreas; Reiser, Maximilian F; Ertl-Wagner, Birgit

    2009-05-01

    The corpus callosum (CC) represents a key structure for hand motor development and is accessible to investigation by diffusion tensor magnetic resonance imaging (DTI) and transcranial magnetic stimulation (TMS). To identify quantifiable markers for motor development, we combined DTI with TMS. We examined groups of 11 healthy preschool-aged children, 10 healthy adolescents, and 10 healthy adults with both, DTI and TMS/ipsilateral silent period (iSP). DTI-values for fractional anisotropy (FA) were calculated for areas I to V of the CC. ISP-values for latency, duration, and extent of electromyography suppression were calculated. FA was significantly lower in areas II to IV of the CC in children as compared with adults (P motor fibers cross the CC, FA differed significantly between children and adolescents (P motor fiber connectivity seems to reflect the degree of interhemispheric inhibition between the motor cortices with anisotropy of callosal motor fibers being a potential marker for motor development.

  14. Absence of Cu-Zn superoxide dismutase BCSOD1 reduces Botrytis cinerea virulence in Arabidopsis and tomato plants, revealing interplay among reactive oxygen species, callose and signalling pathways.

    Science.gov (United States)

    López-Cruz, Jaime; Óscar, Crespo-Salvador; Emma, Fernández-Crespo; Pilar, García-Agustín; Carmen, González-Bosch

    2017-01-01

    Plants activate responses against pathogens, including the oxidative burst. Necrotrophic pathogens can produce reactive oxygen species (ROS) that benefit the colonization process. Previously, we have demonstrated that tomato plants challenged with Botrytis cinerea accumulate ROS and callose, together with the induction of genes involved in defence, signalling and oxidative metabolism. Here, we studied the infection phenotype of the Δbcsod1 strain in both tomato and Arabidopsis plants. This mutant lacks bcsod1, which encodes Cu-Zn superoxide dismutase (SOD). This enzyme catalyses the conversion of superoxide ion ( O2-) into hydrogen peroxide (H2 O2 ). ROS play a protective role and act as signals in plants. Δbcsod1 displayed reduced virulence compared with wild-type B05.10 in both species. Plants infected with Δbcsod1 accumulated less H2 O2 and more O2- than those infected with B05.10, which is associated with an increase in the defensive polymer callose. This supports a major role of fungal SOD in H2 O2 production during the plant-pathogen interaction. The early induction of the callose synthase gene PMR4 suggested that changes in ROS altered plant defensive responses at the transcriptional level. The metabolites and genes involved in signalling and in response to oxidative stress were differentially expressed on Δbcsod1 infection, supporting the notion that plants perceive changes in ROS balance and activate defence responses. A higher O2- /H2 O2 ratio seems to be beneficial for plant protection against this necrotroph. Our results highlight the relevance of callose and the oxylipin 12-oxo-phytodienoic acid (OPDA) in the response to changes in the oxidative environment, and clarify the mechanisms that underlie the responses to Botrytis in Arabidopsis and tomato plants. © 2016 BSPP and John Wiley & Sons Ltd.

  15. Callosal disconnection syndrome in a left-handed patient due to infarction of the total length of the corpus callosum.

    Science.gov (United States)

    Lausberg, H; Göttert, R; Münssinger, U; Boegner, F; Marx, P

    1999-03-01

    We report on a left-handed patient with an ischemic infarction affecting exclusively the total length of the corpus callosum. This lesion clinically correlated with an almost complete callosal disconnection syndrome as described in callosotomy subjects, including unilateral verbal anosmia, hemialexia, unilateral ideomotor apraxia, unilateral agraphia, unilateral tactile anomia, unilateral constructional apraxia, lack of somesthetic transfer and dissociative phenomena. Despite the patient's left-handedness, his pattern of deficits was similar to the disconnection syndrome found in right-handers. Our report focusses on motor dominance and praxis. We followed-up the improvement in left apraxia and investigated the ability to initiate and learn a new visuo-motor skill. The results permit two tentative assumptions: (1) that the improvement in left apraxia was due to a compensatory increase in ipsilateral proximal muscle control, and (2) that motor dominance, i.e. the competence to initiate and learn a new movement pattern, was hemispherically dissociable from manual dominance in the sense of praxis control.

  16. Microstructural callosal abnormalities in normal-appearing brain of children with developmental delay detected with diffusion tensor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Xiao-Qi [Hannover Medical School, Institute of Diagnostic and Interventional Neuroradiology, Hannover (Germany); University Medical Center Hamburg-Eppendorf, Department of Neuroradiology, Hamburg (Germany); Sun, Yimeng; Illies, Till; Zeumer, Hermann; Fiehler, Jens [University Medical Center Hamburg-Eppendorf, Department of Neuroradiology, Hamburg (Germany); Kruse, Bernd [University Medical Center Hamburg-Eppendorf, Department of Pediatrics, Hamburg (Germany); Lanfermann, Heinrich [Hannover Medical School, Institute of Diagnostic and Interventional Neuroradiology, Hannover (Germany)

    2009-06-15

    Callosal fibres play an important role in psychomotor and cognitive functions. The purpose of this study was to investigate possible microstructural abnormalities of the corpus callosum in children with developmental delay, who have normal conventional brain MR imaging results. Seventeen pediatric patients (aged 1-9 years) with developmental delay were studied. Quantitative T2 and fractional anisotropy (FA) values were measured at the genu and splenium of the corpus callosum (CC). Fibre tracking, volumetric determination, as well as fibre density calculations of the CC were also carried out. The results were compared with those of the age-matched healthy subjects. A general elevation of T2 relaxation times (105 ms in patients vs. 95 ms in controls) and reduction of the FA values (0.66 in patients vs. 0.74 in controls) at the genu of the CC were found in patients. Reductions of the fibre numbers (5,464 in patients vs. 8,886 in controls) and volumes (3,415 ml in patients vs. 5,235 ml in controls) of the CC were found only in patients older than 5 years. The study indicates that despite their inconspicuous findings in conventional MRI microstructural brain abnormalities are evident in these pediatric patients suffering from developmental delay. (orig.)

  17. Automatic Segmentation of the Corpus Callosum Using a Cell-Competition Algorithm: Diffusion Tensor Imaging-Based Evaluation of Callosal Atrophy and Tissue Alterations in Patients With Systemic Lupus Erythematosus.

    Science.gov (United States)

    Lee, Shiou-Ping; Wu, Chien-Sheng; Cheng, Jie-Zhi; Chen, Chung-Ming; Chen, Yu-Chiang; Chou, Ming-Chung

    2015-01-01

    Patients with neuropsychiatric systemic lupus erythematosus (NPSLE) may exhibit corpus callosal atrophy and tissue alterations. Measuring the callosal volume and tissue integrity using diffusion tensor imaging (DTI) could help to differentiate patients with NPSLE from patients without NPSLE. Hence, this study aimed to use an automatic cell-competition algorithm to segment the corpus callosum and to investigate the effects of central nervous system (CNS) involvement on the callosal volume and tissue integrity in patients with SLE. Twenty-two SLE patients with (N = 10, NPSLE) and without (N = 12, non-NPSLE) CNS involvement and 22 control subjects were enrolled in this study. For volumetric measurement, a cell-competition algorithm was used to automatically delineate corpus callosal boundaries based on a midsagittal fractional anisotropy (FA) map. After obtaining corpus callosal boundaries for all subjects, the volume, FA, and mean diffusivity (MD) of the corpus callosum were calculated. A post hoc Tamhane's T2 analysis was performed to statistically compare differences among NPSLE, non-NPSLE, and control subjects. A receiver operating characteristic curve analysis was also performed to compare the performance of the volume, FA, and MD of the corpus callosum in differentiating NPSLE from other subjects. Patients with NPSLE had significant decreases in volume and FA but an increase in MD in the corpus callosum compared with control subjects, whereas no significant difference was noted between patients without NPSLE and control subjects. The FA was found to have better performance in differentiating NPSLE from other subjects. A cell-competition algorithm could be used to automatically evaluate callosal atrophy and tissue alterations. Assessments of the corpus callosal volume and tissue integrity helped to demonstrate the effects of CNS involvement in patients with SLE.

  18. Pathology of callosal damage in ALS: An ex-vivo, 7 T diffusion tensor MRI study.

    Science.gov (United States)

    Cardenas, Agustin M; Sarlls, Joelle E; Kwan, Justin Y; Bageac, Devin; Gala, Zachary S; Danielian, Laura E; Ray-Chaudhury, Abhik; Wang, Hao-Wei; Miller, Karla L; Foxley, Sean; Jbabdi, Saad; Welsh, Robert C; Floeter, Mary Kay

    2017-01-01

    The goal of this study was to better understand the changes in tissue microstructure that underlie white matter diffusion changes in ALS patients. Diffusion tensor imaging was carried out in postmortem brains of 4 ALS patients and two subjects without neurological disease on a 7 T MRI scanner using steady-state free precession sequences. Fractional anisotropy (FA) was measured in the genu, body, and splenium of the corpus callosum in formalin-fixed hemispheres. FA of the body and genu was expressed as ratio to FA of the splenium, a region unaffected in ALS. After imaging, tissue sections of the same segments of the callosum were stained for markers of different tissue components. Coded image fields were rated for pathological changes by blinded raters. The FA body/FA splenium ratio was reduced in ALS patients compared to controls. Patchy areas of myelin pallor and cells immunostained for CD68, a microglial-macrophage marker, were only observed in the body of the callosum of ALS patients. Blinded ratings showed increased CD68 + microglial cells in the body of the corpus callosum in ALS patients, especially those with C9orf72 mutations, and increased reactive astrocytes throughout the callosum. Reduced FA of the corpus callosum in ALS results from complex changes in tissue microstructure. Callosal segments with reduced FA had large numbers of microglia-macrophages in addition to loss of myelinated axons and astrogliosis. Microglial inflammation contributed to reduced FA in ALS, and may contribute to a pro-inflammatory state, but further work is needed to determine their role.

  19. Sr36- and Sr5-Mediated Resistance Response to Puccinia graminis f. sp. tritici Is Associated with Callose Deposition in Wheat Guard Cells.

    Science.gov (United States)

    Wang, X; McCallum, B D; Fetch, T; Bakkeren, G; Saville, B J

    2015-06-01

    Race-specific resistance of wheat to Puccinia graminis f. sp. tritici is primarily posthaustorial and often involves the induction of a hypersensitive response (HR). The aim of this study was to investigate host defense responses induced in interactions between P. graminis f. sp. tritici races and wheat lines carrying different race-specific stem rust resistance (Sr) genes. In incompatible interactions between wheat lines carrying Sr36 in three genetic backgrounds (LMPG, Prelude, or W2691) and avirulent P. graminis f. sp. tritici races MCCFC or RCCDM, callose accumulated within 24 h in wheat guard cells contacted by a P. graminis f. sp. tritici appressorium, and P. graminis f. sp. tritici ingress was inhibited following appressorium formation. Accordingly, the expression of transcripts encoding a callose synthase increased in the incompatible interaction between LMPG-Sr36 and avirulent P. graminis f. sp. tritici race MCCFC. Furthermore, the inhibition of callose synthesis through the infiltration of 2-deoxy-D-glucose (DDG) increased the ability of P. graminis f. sp. tritici race MCCFC to infect LMPG-Sr36. A similar induction of callose deposition in wheat guard cells was also observed within 24 h after inoculation (hai) with avirulent P. graminis f. sp. tritici race HKCJC on LMPG-Sr5 plants. In contrast, this defense response was not induced in incompatible interactions involving Sr6, Sr24, or Sr30. Instead, the induction of an HR and cellular lignification were noted. The manifestation of the HR and cellular lignification was induced earlier (24 hai) and was more extensive in the resistance response mediated by Sr6 compared with those mediated by Sr24 or Sr30. These results indicate that the resistance mediated by Sr36 is similar to that mediated by Sr5 but different from those triggered by Sr6, Sr24, or Sr30. Resistance responses mediated by Sr5 and Sr36 are prehaustorial, and are a result of very rapid recognition of molecules derived from avirulent isolates of

  20. Signalling requirements for Erwinia amylovora-induced disease resistance, callose deposition and cell growth in the non-host Arabidopsis thaliana.

    Science.gov (United States)

    Hamdoun, Safae; Gao, Min; Gill, Manroop; Kwon, Ashley; Norelli, John L; Lu, Hua

    2017-07-29

    Erwinia amylovora is the causal agent of the fire blight disease in some plants of the Rosaceae family. The non-host plant Arabidopsis serves as a powerful system for the dissection of mechanisms of resistance to E. amylovora. Although not yet known to mount gene-for-gene resistance to E. amylovora, we found that Arabidopsis activated strong defence signalling mediated by salicylic acid (SA), with kinetics and amplitude similar to that induced by the recognition of the bacterial effector avrRpm1 by the resistance protein RPM1. Genetic analysis further revealed that SA signalling, but not signalling mediated by ethylene (ET) and jasmonic acid (JA), is required for E. amylovora resistance. Erwinia amylovora induces massive callose deposition on infected leaves, which is independent of SA, ET and JA signalling and is necessary for E. amylovora resistance in Arabidopsis. We also observed tumour-like growths on E. amylovora-infected Arabidopsis leaves, which contain enlarged mesophyll cells with increased DNA content and are probably a result of endoreplication. The formation of such growths is largely independent of SA signalling and some E. amylovora effectors. Together, our data reveal signalling requirements for E. amylovora-induced disease resistance, callose deposition and cell fate change in the non-host plant Arabidopsis. Knowledge from this study could facilitate a better understanding of the mechanisms of host defence against E. amylovora and eventually improve host resistance to the pathogen. © 2017 BSPP AND JOHN WILEY & SONS LTD.

  1. Heterogeneity of trans-callosal structural connectivity and effects on resting state subnetwork integrity may underlie both wanted and unwanted effects of therapeutic corpus callostomy

    Directory of Open Access Journals (Sweden)

    Peter Neal Taylor

    2016-01-01

    Conclusion: Consideration of the selective vulnerability of resting state sub-networks, and of between-individual variability in connectivity patterns, sheds new light on the occurrence of both wanted and unwanted effects of callosotomy. We propose that beneficial effects (seizure reduction relate to disruption of the default mode network, with unwanted “disconnection syndrome” effects due to disruption particularly of the somatomotor and frontoparietal RSNs. Our results may also explain why disconnection syndromes primary reflect lateralised sensory-motor problems (e.g. of limb movement rather than midline function (e.g. tongue movement. Marked between-subject variation in callosal connectivity may underlie the poor predictability of effects of callosotomy. High resolution structural connectivity studies of this nature may be useful in pre-surgical planning of therapeutic callosotomy for intractable epilepsy.

  2. The Arabidopsis thaliana Knockout Mutant for Phytochelatin Synthase1 (cad1-3 Is Defective in Callose Deposition, Bacterial Pathogen Defense and Auxin Content, But Shows an Increased Stem Lignification

    Directory of Open Access Journals (Sweden)

    Maria De Benedictis

    2018-01-01

    Full Text Available The enzyme phytochelatin synthase (PCS has long been studied with regard to its role in metal(loid detoxification in several organisms, i.e., plants, yeasts, and nematodes. It is in fact widely recognized that PCS detoxifies a number of heavy metals by catalyzing the formation of thiol-rich oligomers, namely phytochelatins, from glutathione and related peptides. However, recent investigations have highlighted other possible roles played by the PCS enzyme in the plant cell, e.g., the control of pathogen-triggered callose deposition. In order to examine novel aspects of Arabidopsis thaliana PCS1 (AtPCS1 functions and to elucidate its possible roles in the secondary metabolism, metabolomic data of A. thaliana wild-type and cad1-3 mutant were compared, the latter lacking AtPCS1. HPLC-ESI-MS analysis showed differences in the relative levels of metabolites from the glucosinolate and phenylpropanoid pathways between cad1-3 and wild-type plants. Specifically, in control (Cd-untreated plants, higher levels of 4-methoxy-indol-3-ylmethylglucosinolate were found in cad1-3 plants vs. wild-type. Moreover, the cad1-3 mutant showed to be impaired in the deposit of callose after Cd exposure, suggesting that AtPCS1 protects the plant against the toxicity of heavy metals not only by synthesizing PCs, but also by contributing to callose deposition. In line with the contribution of callose in counteracting Cd toxicity, we found that another callose-defective mutant, pen2-1, was more sensitive to high concentrations of Cd than wild-type plants. Moreover, cad1-3 plants were more susceptible than wild-type to the hemibiotrophic bacterial pathogen Pseudomonas syringae. The metabolome also revealed differences in the relative levels of hydroxycinnamic acids and flavonols, with consequences on cell wall properties and auxin content, respectively. First, increased lignification in the cad1-3 stems was found, probably aimed at counteracting the entry of Cd into the inner

  3. The PTI1-like kinase ZmPti1a from maize (Zea mays L.) co-localizes with callose at the plasma membrane of pollen and facilitates a competitive advantage to the male gametophyte.

    Science.gov (United States)

    Herrmann, Markus M; Pinto, Sheena; Kluth, Jantjeline; Wienand, Udo; Lorbiecke, René

    2006-10-06

    The tomato kinase Pto confers resistance to bacterial speck disease caused by Pseudomonas syringae pv. tomato in a gene for gene manner. Upon recognition of specific avirulence factors the Pto kinase activates multiple signal transduction pathways culminating in induction of pathogen defense. The soluble cytoplasmic serine/threonine kinase Pti1 is one target of Pto phosphorylation and is involved in the hypersensitive response (HR) reaction. However, a clear role of Pti1 in plant pathogen resistance is uncertain. So far, no Pti1 homologues from monocotyledonous species have been studied. Here we report the identification and molecular analysis of four Pti1-like kinases from maize (ZmPti1a, -b, -c, -d). These kinase genes showed tissue-specific expression and their corresponding proteins were targeted to different cellular compartments. Sequence similarity, expression pattern and cellular localization of ZmPti1b suggested that this gene is a putative orthologue of Pti1 from tomato. In contrast, ZmPti1a was specifically expressed in pollen and sequestered to the plasma membrane, evidently owing to N-terminal modification by myristoylation and/or S-acylation. The ZmPti1a:GFP fusion protein was not evenly distributed at the pollen plasma membrane but accumulated as an annulus-like structure which co-localized with callose (1,3-beta-glucan) deposition. In addition, co-localization of ZmPti1a and callose was observed during stages of pollen mitosis I and pollen tube germination. Maize plants in which ZmPti1a expression was silenced by RNA interference (RNAi) produced pollen with decreased competitive ability. Hence, our data provide evidence that ZmPti1a plays an important part in a signalling pathway that accelerates pollen performance and male fitness. ZmPti1a from maize is involved in pollen-specific processes during the progamic phase of reproduction, probably in crucial signalling processes associated with regions of callose deposition. Pollen

  4. The PTI1-like kinase ZmPti1a from maize (Zea mays L. co-localizes with callose at the plasma membrane of pollen and facilitates a competitive advantage to the male gametophyte

    Directory of Open Access Journals (Sweden)

    Wienand Udo

    2006-10-01

    Full Text Available Abstract Background The tomato kinase Pto confers resistance to bacterial speck disease caused by Pseudomonas syringae pv. tomato in a gene for gene manner. Upon recognition of specific avirulence factors the Pto kinase activates multiple signal transduction pathways culminating in induction of pathogen defense. The soluble cytoplasmic serine/threonine kinase Pti1 is one target of Pto phosphorylation and is involved in the hypersensitive response (HR reaction. However, a clear role of Pti1 in plant pathogen resistance is uncertain. So far, no Pti1 homologues from monocotyledonous species have been studied. Results Here we report the identification and molecular analysis of four Pti1-like kinases from maize (ZmPti1a, -b, -c, -d. These kinase genes showed tissue-specific expression and their corresponding proteins were targeted to different cellular compartments. Sequence similarity, expression pattern and cellular localization of ZmPti1b suggested that this gene is a putative orthologue of Pti1 from tomato. In contrast, ZmPti1a was specifically expressed in pollen and sequestered to the plasma membrane, evidently owing to N-terminal modification by myristoylation and/or S-acylation. The ZmPti1a:GFP fusion protein was not evenly distributed at the pollen plasma membrane but accumulated as an annulus-like structure which co-localized with callose (1,3-β-glucan deposition. In addition, co-localization of ZmPti1a and callose was observed during stages of pollen mitosis I and pollen tube germination. Maize plants in which ZmPti1a expression was silenced by RNA interference (RNAi produced pollen with decreased competitive ability. Hence, our data provide evidence that ZmPti1a plays an important part in a signalling pathway that accelerates pollen performance and male fitness. Conclusion ZmPti1a from maize is involved in pollen-specific processes during the progamic phase of reproduction, probably in crucial signalling processes associated with regions

  5. Diffusion tensor imaging with three-dimensional fiber tractography of traumatic axonal shearing injury: an imaging correlate for the posterior callosal "disconnection" syndrome: case report.

    Science.gov (United States)

    Le, Tuong H; Mukherjee, Pratik; Henry, Roland G; Berman, Jeffrey I; Ware, Marcus; Manley, Geoffrey T

    2005-01-01

    To demonstrate that magnetic resonance diffusion tensor imaging (DTI) with three-dimensional (3-D) fiber tractography can visualize traumatic axonal shearing injury that results in posterior callosal disconnection syndrome. A 22-year-old man underwent serial magnetic resonance imaging 3 days and 12 weeks after blunt head injury. The magnetic resonance images included whole-brain DTI acquired with a single-shot spin echo echoplanar sequence. 3-D DTI fiber tractography of the splenium of the corpus callosum was performed. Quantitative DTI parameters, including apparent diffusion coefficient and fractional anisotropy, from the site of splenial injury were compared with those of a normal adult male volunteer. Conventional magnetic resonance images revealed findings of diffuse axonal injury, including a lesion at the midline of the splenium of the corpus callosum. DTI performed 3 days posttrauma revealed that the splenial lesion had reduced apparent diffusion coefficient and fractional anisotropy, reflecting a large decrease in the magnitude of diffusion parallel to the white matter fibers, which had partially recovered as revealed by follow-up DTI 12 weeks postinjury. 3-D tractography revealed an interruption of the white matter fibers in the posteroinferior aspect of the splenium that correlated with the patient's left hemialexia, a functional deficit caused by disconnection of the right visual cortex from the language centers of the dominant left hemisphere. DTI with 3-D fiber tractography can visualize acute axonal shearing injury, which may have prognostic value for the cognitive and neurological sequelae of traumatic brain injury.

  6. [Case of callosal disconnection syndrome with a chief complaint of right-hand disability, despite presence of left-hand diagonistic dyspraxia].

    Science.gov (United States)

    Okamoto, Yoko; Saida, Hisako; Yamamoto, Toru

    2009-04-01

    e report the case of 48-year-old right-handed male patient with an infarction affecting most part of the body and the splenium of the left half of the corpus callosum. Neuropsychological examination revealed typical signs of callosal disconnection including left-sided apraxia, diagonistic dyspraxia, left-sided agraphia, left-hand tactile anomia, left hemialexia, and right-sided constructional disability. Moreover, he complained of impairment in activities involving the right hand disability and agraphia. He could not stop behaving with his right hand when he had a vague idea. For example, he involuntarily picked up a tea bottle with his right hand when he had a desire to drink, although the action was not appropriate to that occasion. The imitation and utilization behavior did not imply this case, because his right hand behaviors were not exaggerated in response to external stimuli, such as the gestures of the examiner or the subjects in front of the patient. Unexpectedly, he complained about impairment of the activity of his right hand and was unaware of left hand apraxia or diagonistic dyspraxia; this trend continued for 6 months, at the time of this writing. We argue that the patient may have been subconsciouly aware of the symptoms of his left hand but had not verbalized them.

  7. Anton's syndrome following callosal disconnection.

    Science.gov (United States)

    Abutalebi, J; Arcari, C; Rocca, M A; Rossi, P; Comola, M; Comi, G C; Rovaris, M; Filippi, M

    2007-01-01

    Anosognosia for cortical blindness, also called Anton's syndrome, is a rare neurological disorder usually following bilateral lesions to occipital cortices. Neuropsychological, morphological and functional neuroimaging (SPECT and fMRI) findings are reported in a patient who incurred Anton's syndrome after an ischaemic lesion confined to the left occipital lobe involving the corpus callosum. The present case study suggests that Anton's syndrome may also follow from lesions disconnecting the occipital cortices.

  8. Overexpression of the transcription factor RAP2.6 leads to enhanced callose deposition in syncytia and enhanced resistance against the beet cyst nematode Heterodera schachtii in Arabidopsis roots

    Science.gov (United States)

    2013-01-01

    Background Cyst nematodes invade the roots of their host plants as second stage juveniles and induce a syncytium which is their source of nutrients throughout their life. A transcriptome analysis of syncytia induced by the beet cyst nematode Heterodera schachtii in Arabidopsis roots has shown that gene expression in the syncytium is different from that of the root with thousands of genes upregulated or downregulated. Among the downregulated genes are many which code for defense-related proteins. One gene which is strongly downregulated codes for the ethylene response transcription factor RAP2.6. The genome of Arabidopsis contains 122 ERF transcription factor genes which are involved in a variety of developmental and stress responses. Results Expression of RAP2.6 was studied with RT-PCR and a promoter::GUS line. During normal growth conditions the gene was expressed especially in roots and stems. It was inducible by Pseudomonas syringae but downregulated in syncytia from a very early time point on. Overexpression of the gene enhanced the resistance against H. schachtii which was seen by a lower number of nematodes developing on these plants as well as smaller syncytia and smaller female nematodes. A T-DNA mutant had a reduced RAP2.6 transcript level but this did not further increase the susceptibility against H. schachtii. Neither overexpression lines nor mutants had an effect on P. syringae. Overexpression of RAP2.6 led to an elevated expression of JA-responsive genes during early time points after infection by H. schachtii. Syncytia developing on overexpression lines showed enhanced deposition of callose. Conclusions Our results showed that H. schachtii infection is accompanied by a downregulation of RAP2.6. It seems likely that the nematodes use effectors to actively downregulate the expression of this and other defense-related genes to avoid resistance responses of the host plant. Enhanced resistance of RAP2.6 overexpression lines seemed to be due to enhanced

  9. Distinctive patterns of callose deposition provide an early sign of ovule abortion1 in the andromonoecious shrub Caesalpinia gilliesii Patrones distintivos de deposición de calosa proveen evidencia temprana de aborto de óvulos en el arbusto andromonoico Caesalpinia gilliesii

    Directory of Open Access Journals (Sweden)

    A. Calviño

    2009-07-01

    Full Text Available Ovule abortion may lead to the partial or complete reduction of the number of functional ovules in the ovary and then is the primary factor that determines the sexual expression of the plant. In different species, ovule abortion was associated with the presence of callose in advanced ovules. Based on these observations, we studied the pattern of ovule development and callose deposition in both perfect and staminate flowers of the andromonoecious shrub Caesalpinia gilliesii. The obtained results showed that all ovules reached the 8-nucleate stage of embryo sac development and exhibited callose deposition at advanced stages. Nevertheless, from the 2-nucleate stage, a distinct spatial pattern of callose deposition within the ovule was observed between perfect and staminate flowers. Differences in callose deposition suggest that not callose per se but its distribution pattern in the ovule tissues is the main factor that triggers ovule isolation and abortion and leads to flowers with non-functional pistils in this species. Furthermore, previous observed differential growth rates between perfect and staminate flowers support for resource depletion as the likely underlying mechanism of ovule fate in C. gilliesii.El aborto de óvulos puede llevar a la reducción parcial o completa de óvulos fértiles en el ovario, pudiendo ser entonces un factor primario que determine la expresión sexual de toda la planta. En diferentes especies de plantas, el aborto de los óvulos ha sido asociado con la presencia de calosa en estadios avanzados del desarrollo de los óvulos. Basado en estas observaciones, se estudiaron el desarrollo de los óvulos y el patrón de deposición de calosa tanto en flores perfectas como estaminadas en el arbusto andromonoico C. gilliesii. Los resultados obtenidos muestran que los sacos embrionarios alcanzan el estadio de desarrollo 8-nucleado en todos los óvulos, y que presentan deposición de calosa en los estadios avanzados. Sin

  10. Genetic effects in callose content in root apex of inbred resistant and susceptible corn lines to acid soils Efectos genéticos de la formación de calosa en ápices radicales de líneas de maíz resistentes y susceptibles a suelos ácidos

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    Arcos Alba Lucía

    2007-12-01

    Full Text Available

    The main objective of this work was to identify genetic parameters that are related to callose accumulation using tropical inbreeds corn. Fourteen inbreed lines selected for different levels of tolerance to acid soils were chosen and a diallel among them was generated. The seeds were grown under controlled environmental conditions in a growth chamber and transferred to a nutrient solution at pH 4.3. After 12 hours of 25 µM Al (AlCl3 treatment was applied, callose contents of 1 cm root apex were determined with fluorescence spectrophotometer. Significant differences were found for parents, crosses and parents vs crosses. Average callose content varied from 0.746 to 2.035 (µg PE/cm root apex. Heterosis varied from –21.2% to 276.3%. General combining ability (GCA and specific combining ability (SCA were highly significant indicating that both, additive and non–additive gene effects were important for callose inheritance. SCA and GCA sum of squares accounted for 54% and 46%, respectively of crosses of squares sum. Correlation coefficient between callose content and corn grain yield in the field was negative but not significant (r = –0.38.

    Key words: Zea mays; callose; inheritance; diallel; heterosis; acid soils.

    El objetivo de este trabajo fue estudiar la herencia de la producción de calosa utilizando líneas endogámicas de maíz. Seleccionando 14 líneas (7 tolerantes y 7 susceptibles a suelos ácidos se formó un dialelo que fue probado en campo y en invernadero. Se determinó el contenido de calosa en los 91 cruzamientos resultantes y los 14 progenitores. Para ello se colocaron las semillas en cámara de crecimiento en condiciones controladas. Después de 4–5 días las plántulas fueron transferidas a cubetas que contenían solución nutritiva con aireación constante. Luego de 48 horas se adicionaron 25 µM de aluminio (AlCl3 a cada una de las cubetas y se mantuvieron por 12 horas. Se cortaron tres ápices radicales de

  11. Efectos genéticos de la formación de calosa en ápices radicales de líneas de maíz resistentes y susceptibles a suelos ácidos Genetic effects in callose content in root apex of inbred resistant and susceptible corn lines to acid soils

    Directory of Open Access Journals (Sweden)

    Alba Lucía Arcos

    2007-01-01

    Full Text Available El objetivo de este trabajo fue estudiar la herencia de la producción de calosa utilizando líneas endogámicas de maíz. Seleccionando 14 líneas (7 tolerantes y 7 susceptibles a suelos ácidos se formó un dialelo que fue probado en campo y en invernadero. Se determinó el contenido de calosa en los 91 cruzamientos resultantes y los 14 progenitores. Para ello se colocaron las semillas en cámara de crecimiento en condiciones controladas. Después de 4-5 días las plántulas fueron transferidas a cubetas que contenían solución nutritiva con aireación constante. Luego de 48 horas se adicionaron 25 µM de aluminio (AlCl3 a cada una de las cubetas y se mantuvieron por 12 horas. Se cortaron tres ápices radicales de cada genotipo y se mantuvieron en etanol 96%. Para medir el contenido de calosa se utilizó Methyl blue como colorante, este forma un complejo con la calosa llamado Siruflúor-calosa, que es medido con el espectrofotómetro de fluorescencia. Se encontraron diferencias significativas para los progenitores, los cruzamientos y los progenitores Vs cruzamientos. El contenido de calosa de los progenitores varió de 0.746 a 2.035 µg PE/cm ápice de raíz. La heterosis varió desde -21.2% a 276.3%. La Habilidad Combinatoria General (HCG y la Habilidad Combinatoria Específica (HCE fueron altamente significativas, lo que indica que tanto los efectos genéticos aditivos y no aditivos fueron importantes en la herencia de calosa. El 46% de SC entre cruzamientos correspondió a la HCG y el 54% a la HCE. El coeficiente de correlación entre el contenido de calosa y la producción de grano del maíz en el campo fue negativo aunque no significativo (r = -0.38.The main objective of this work was to identify genetic parameters that are related to callose accumulation using tropical inbreeds corn. Fourteen inbreed lines selected for different levels of tolerance to acid soils were chosen and a diallel among them was generated. The seeds were grown

  12. Anton?s Syndrome following Callosal Disconnection

    OpenAIRE

    Abutalebi, J.; Arcari, C; Rocca, M. A.; de Rossi, P; Comola, M; Comi, G. C.; Rovaris, M.; Filippi, M.

    2007-01-01

    Anosognosia for cortical blindness, also called Anton?s syndrome, is a rare neurological disorder usually following bilateral lesions to occipital cortices. Neuropsychological, morphological and functional neuroimaging (SPECT and fMRI) findings are reported in a patient who incurred Anton?s syndrome after an ischaemic lesion confined to the left occipital lobe involving the corpus callosum. The present case study suggests that Anton's syndrome may also follow from lesions disconnecting the oc...

  13. Callosal and cortical contribution to procedural learning.

    Science.gov (United States)

    de Guise, E; del Pesce, M; Foschi, N; Quattrini, A; Papo, I; Lassonde, M

    1999-06-01

    Acallosal and callosotomized subjects usually show impairments on tasks requiring bilateral interdependent motor control. However, few studies have assessed the ability of these subjects to learn a skill that requires the simultaneous contribution of each hemisphere in its acquisition. The present study examined whether acallosal and callosotomized subjects could learn a visuomotor skill that involved a motor control from either both or a single hemisphere. Eleven adult patients, six acallosal and five callosotomized, participated in this study. Seven of these patients had epileptic foci located in the frontal and/or temporal areas and one of the acallosal patients showed bilateral prefrontal atrophy following surgical removal of an orbitofrontal cyst. The performance of the experimental subjects was compared with that of 11 matched control subjects, on a modified version of a serial reaction time task developed by Nissen and Bullemer (Cogn Psychol 1987; 19: 1-32). This skill acquisition task involved bimanual or unimanual key-pressing responses to a sequence of 10 visual stimuli that was repeated 160 times. A declarative memory task was then performed to assess explicit knowledge of the sequence. None of the experimental subjects learned the task in the bimanual condition. Patients with frontal epileptic foci or orbitofrontal damage also failed to learn the task in the unimanual condition when they were using the hand contralateral to the damaged hemisphere. All other subjects, including the acallosal and callosotomized patients with temporal foci, learned the visuomotor skill as well as their controls in the unimanual condition. In spite of the absence of transfer and interhemispheric integration of procedural learning, some of the acallosal and callosotomized patients were able to learn the sequence explicitly. These findings indicate that the corpus callosum and the frontal cortical areas are important for procedural learning of a visuomotor skill. They also confirm the dissociation described by Squire (Science 1986; 232: 1612-9 and J Cogn Neurosci 1992; 4: 232-43) between the declarative and procedural memory systems and extend this dissociation to processes involving simultaneous bihemispheric co-operation.

  14. Reliability of measuring regional callosal atrophy in neurodegenerative diseases

    Directory of Open Access Journals (Sweden)

    Jeroen Van Schependom, MSc Eng, PhD

    2016-01-01

    In summary, we have constructed an algorithm that reliably detects the CC in 3D T1 images in a fully automated way in healthy controls and different neurodegenerative diseases. Although the CC area and the circularity are the most reliable features (ICC > 0.97; the reliability of the thickness profile (ICC > 0.90; excluding the tip is sufficient to warrant its inclusion in future clinical studies.

  15. ROBO1 polymorphisms, callosal connectivity, and reading skills.

    Science.gov (United States)

    Sun, Xiaochen; Song, Shuang; Liang, Xinyu; Xie, Yachao; Zhao, Chenxi; Zhang, Yuping; Shu, Hua; Gong, Gaolang

    2017-05-01

    The genetic effects on specific behavioral phenotypes are putatively mediated by specific neural functions. It remains unexplored how the axon-guidance-receptor gene ROBO1 influences reading performance through the neural system despite the identification of ROBO1 as a susceptibility gene for dyslexia. To address this issue, the present study recruited a group of children with a wide range of reading abilities. Two previously identified reading-related ROBO1 polymorphisms were genotyped, and diffusion and structural MRI were acquired to measure the fiber microstructure of the corpus callosum (CC), the major white-matter tract that connects inter-hemispheric cortical regions. The results confirmed the significant influence of the ROBO1 polymorphisms on reading scores. The fiber microstructures of the midline-CC segments around the genu and splenium were also affected by the ROBO1 polymorphisms. Moreover, a mediation analysis further revealed that the genu could significantly mediate the effects of the ROBO1 polymorphisms on word-list reading performance, which suggests a ROBO1-to-genu-to-reading pathway. The genu-linked cortical morphology, however, was not associated with either the ROBO1 polymorphisms or reading performance. These findings offer direct evidence supporting ROBO1-callosum association in humans and also provide valuable insight into the functions of ROBO1 and the gene-to-brain mechanisms that underlie human reading. Hum Brain Mapp 38:2616-2626, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. Perinatal exposure to music protects spatial memory against callosal lesions.

    Science.gov (United States)

    Amagdei, Anca; Balteş, Felicia Rodica; Avram, Julia; Miu, Andrei C

    2010-02-01

    Several studies have indicated that the exposure of rodents to music modulates brain development and neuroplasticity, by mechanisms that involve facilitated hippocampal neurogenesis, neurotrophin synthesis and glutamatergic signaling. This study focused on the potential protection that the perinatal exposure to music, between postnatal days 2 and 32, could offer against functional deficits induced by neonatal callosotomy in rats. The spontaneous alternation and marble-burying behaviors were longitudinally measured in callosotomized and control rats that had been exposed to music or not. The results indicated that the neonatal callosotomy-induced spontaneous alternation deficits that became apparent only after postnatal day 45, about the time when the rat corpus callosum reaches its maximal levels of myelination. The perinatal exposure to music efficiently protected the spontaneous alternation performance against the deficits induced by callosotomy. The present findings may offer important insights into music-induced neuroplasticity, relevant to brain development and neurorehabilitation. Copyright 2009 ISDN. Published by Elsevier Ltd. All rights reserved.

  17. Left hand tactile agnosia after posterior callosal lesion.

    Science.gov (United States)

    Balsamo, Maddalena; Trojano, Luigi; Giamundo, Arcangelo; Grossi, Dario

    2008-09-01

    We report a patient with a hemorrhagic lesion encroaching upon the posterior third of the corpus callosum but sparing the splenium. She showed marked difficulties in recognizing objects and shapes perceived through her left hand, while she could appreciate elementary sensorial features of items tactually presented to the same hand flawlessly. This picture, corresponding to classical descriptions of unilateral associative tactile agnosia, was associated with finger agnosia of the left hand. This very unusual case report can be interpreted as an instance of disconnection syndrome, and allows a discussion of mechanisms involved in tactile object recognition.

  18. Cannabis use and callosal white matter structure and integrity in recent-onset schizophrenia

    NARCIS (Netherlands)

    Dekker, Nienke; Schmitz, Nicole; Peters, Bart D.; van Amelsvoort, Therese A.; Linszen, Don H.; de Haan, Lieuwe

    2010-01-01

    Adolescent-onset cannabis use, compared with adult-onset use, has been associated with a higher risk for developing symptoms of schizophrenia-like psychotic disorders. To test the hypothesis that onset of cannabis use in early adolescence in male schizophrenia patients is associated with

  19. Malformations of the midline commissures: MRI findings in different forms of callosal dysgenesis

    Energy Technology Data Exchange (ETDEWEB)

    Kueker, W.; Mader, I.; Naegele, T. [Department of Neuroradiology, Medical School, University of Tuebingen, Hoppe-Seyler Strasse 3, 72076 Tuebingen (Germany); Mayrhofer, H.; Kraegeloh-Mann, I. [Department Neuropaediatrics, Medical School, University of Tuebingen, Hoppe-Seyler Strasse 3, 72076 Tuebingen (Germany)

    2003-03-01

    Malformations of the corpus callosum (CC) may occur in many different syndromes. Various forms have been observed. We report seven cases of malformation of the CC. Special attention is directed towards the development of the fornix and hippocampus as a hippocampal commissure is a prerequisite of normal hippocampal development. The clinical disability of the patients presented here differed significantly, which may in part be due to the different extent of this cerebral malformation. The relevance of the concomitant aplasia of the limbic system has not been addressed in detail previously in the literature. (orig.)

  20. Structural integrity of callosal midbody influences intermanual transfer in a motor reaction-time task.

    Science.gov (United States)

    Bonzano, Laura; Tacchino, Andrea; Roccatagliata, Luca; Mancardi, Giovanni Luigi; Abbruzzese, Giovanni; Bove, Marco

    2011-02-01

    Training one hand on a motor task results in performance improvements in the other hand, also when stimuli are randomly presented (nonspecific transfer). Corpus callosum (CC) is the main structure involved in interhemispheric information transfer; CC pathology occurs in patients with multiple sclerosis (PwMS) and is related to altered performance of tasks requiring interhemispheric transfer of sensorimotor information. To investigate the role of CC in nonspecific transfer during a pure motor reaction-time task, we combined motor behavior with diffusion tensor imaging analysis in PwMS. Twenty-two PwMS and 10 controls, all right-handed, were asked to respond to random stimuli with appropriate finger opposition movements with the right (learning) and then the left (transfer) hand. PwMS were able to improve motor performance reducing response times with practice with a trend similar to controls and preserved the ability to transfer the acquired motor information from the learning to the transfer hand. A higher variability in the transfer process, indicated by a significantly larger standard deviation of mean nonspecific transfer, was found in the PwMS group with respect to the control group, suggesting the presence of subtle impairments in interhemispheric communication in some patients. Then, we correlated the amount of nonspecific transfer with mean fractional anisotropy (FA) values, indicative of microstructural damage, obtained in five CC subregions identified on PwMS's FA maps. A significant correlation was found only in the subregion including posterior midbody (Pearson's r = 0.74, P = 0.003), which thus seems to be essential for the interhemispheric transfer of information related to pure sensorimotor tasks. Copyright © 2010 Wiley-Liss, Inc.

  1. Paralinguistic Processing in Children with Callosal Agenesis: Emergence of Neurolinguistic Deficits

    Science.gov (United States)

    Brown, W.S.; Symingtion, M.; VanLancker-Sidtis, D.; Dietrich, R.; Paul, L.K.

    2005-01-01

    Recent research revealed impaired processing of both nonliteral meaning and affective prosody in adults with agenesis of the corpus callosum (ACC) and normal intelligence. Since normal children have incomplete myelination of the corpus callosum, it was hypothesized that paralanguage deficits in children with ACC would be less apparent relative to…

  2. Callosal Function in Pediatric Traumatic Brain Injury Linked to Disrupted White Matter Integrity.

    Science.gov (United States)

    Dennis, Emily L; Ellis, Monica U; Marion, Sarah D; Jin, Yan; Moran, Lisa; Olsen, Alexander; Kernan, Claudia; Babikian, Talin; Mink, Richard; Babbitt, Christopher; Johnson, Jeffrey; Giza, Christopher C; Thompson, Paul M; Asarnow, Robert F

    2015-07-15

    Traumatic brain injury (TBI) often results in traumatic axonal injury and white matter (WM) damage, particularly to the corpus callosum (CC). Damage to the CC can lead to impaired performance on neurocognitive tasks, but there is a high degree of heterogeneity in impairment following TBI. Here we examined the relation between CC microstructure and function in pediatric TBI. We used high angular resolution diffusion-weighted imaging (DWI) to evaluate the structural integrity of the CC in humans following brain injury in a sample of 32 children (23 males and 9 females) with moderate-to-severe TBI (msTBI) at 1-5 months postinjury, compared with well matched healthy control children. We assessed CC function through interhemispheric transfer time (IHTT) as measured using event-related potentials (ERPs), and related this to DWI measures of WM integrity. Finally, the relation between DWI and IHTT results was supported by additional results of neurocognitive performance assessed using a single composite performance scale. Half of the msTBI participants (16 participants) had significantly slower IHTTs than the control group. This slow IHTT group demonstrated lower CC integrity (lower fractional anisotropy and higher mean diffusivity) and poorer neurocognitive functioning than both the control group and the msTBI group with normal IHTTs. Lower fractional anisotropy-a common sign of impaired WM-and slower IHTTs also predicted poor neurocognitive function. This study reveals that there is a subset of pediatric msTBI patients during the post-acute phase of injury who have markedly impaired CC functioning and structural integrity that is associated with poor neurocognitive functioning. Traumatic brain injury (TBI) is the primary cause of death and disability in children and adolescents. There is considerable heterogeneity in postinjury outcome, which is only partially explained by injury severity. Imaging biomarkers may help explain some of this variance, as diffusion weighted imaging is sensitive to the white matter disruption that is common after injury. The corpus callosum (CC) is one of the most commonly reported areas of disruption. In this multimodal study, we discovered a divergence within our pediatric moderate-to-severe TBI sample 1-5 months postinjury. A subset of the TBI sample showed significant impairment in CC function, which is supported by additional results showing deficits in CC structural integrity. This subset also had poorer neurocognitive functioning. Our research sheds light on postinjury heterogeneity. Copyright © 2015 the authors 0270-6474/15/3510203-10$15.00/0.

  3. Inter-hemispheric wave propagation failures in traumatic brain injury are indicative of callosal damage.

    Science.gov (United States)

    Spiegel, Daniel P; Laguë-Beauvais, Maude; Sharma, Gaurav; Farivar, Reza

    2015-04-01

    Approximately 3.2-5.3 million Americans live with the consequences of a traumatic brain injury (TBI), making TBI one of the most common causes of disability in the world. Visual deficits often accompany TBI but physiological and anatomical evidence for injury in mild TBI is lacking. Axons traversing the corpus callosum are particularly vulnerable to TBI. Hemifield representations of early visual areas are linked by bundles of fibers that together cross the corpus callosum while maintaining their topographic relations. Given the increased vulnerability of the long visual axons traversing the corpus callosum, we hypothesized that inter-hemispheric transmission for vision will be impaired following mild TBI. Using the travelling wave paradigm (Wilson, Blake, & Lee 2001), we measured inter-hemispheric transmission in terms of both speed and propagation failures in 14 mild TBI patients and 14 age-matched controls. We found that relative to intra-hemispheric waves, inter-hemispheric waves were faster and that the inter-hemispheric propagation failures were more common in TBI patients. Furthermore, the transmission failures were topographically distributed, with a bias towards greater failures for transmission across the upper visual field. We discuss the results in terms of increased local inhibition and topographically-selective axonal injury in mild TBI. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Callosal tissue loss parallels subtle decline in psychomotor speed. A longitudinal quantitative MRI study. The LADIS Study

    DEFF Research Database (Denmark)

    Jokinen, Hanna; Frederiksen, Kristian S; Garde, Ellen

    2012-01-01

    tissue loss on cognitive decline was analyzed with hierarchical linear regression models. After controlling for age, sex, education, and baseline cognitive performance, the rates of tissue loss in the total CC area, and in rostrum/genu and midbody subregions were significantly associated with decline...

  5. Callosal disconnection syndrome and knowledge of the body: a case of left hand isolation from the body schema with names.

    Science.gov (United States)

    Nagumo, T; Yamadori, A

    1995-01-01

    A patient is described who presented with a disturbance of body cognition confined to the left side of the body. She showed difficulties in naming the left fingers and in moving the named left fingers. She also showed great difficulty in pointing to named parts of the body with her left hand. Earlier in the course of the disease she showed a personification phenomenon of the left hand. Brain MRI showed involvement of the entire corpus callosum, probably due to occlusion of a branch of the anterior cerebral artery. It is speculated that this syndrome is caused by disconnection of the right hemisphere from the left hemispheric body schema. Images PMID:8530946

  6. Signaling requirements for Erwinia amylovora-induced disease resistance, callose deposition, and cell growth in the nonhost Arabidopsis thaliana

    Science.gov (United States)

    Erwinia amylovora is the causal agent of the fire blight disease in some plants of the Rosaceae family. The nonhost plant Arabidopsis serves as a powerful system to dissect mechanisms of resistance to E. amylovora. Although not yet known to mount gene-for-gene resistance to E. amylovora, we found ...

  7. Normative Data of Corpus Callosal Morphology in a North-West Indian Population- An autopsy and MRI study

    Directory of Open Access Journals (Sweden)

    Tulika Gupta

    2009-01-01

    The values of different CC parameters observed were almost similar to the values reported in the other two Indian studies. However, Indian values were found to be more than the Japanese values for length, height and most of the widths of CC. The length and width of CC were found to be less than those of Caucasian population. Generation of this data will help in comparing the CC structure of different sex and ages, to study variations from the normal and may help in surgical planning. Keywords:autopsy brains; corpus callosum; magnetic resonance imaging; morphometric data.

  8. Development of the Corticospinal and Callosal Tracts from Extremely Premature Birth up to 2 Years of Age

    NARCIS (Netherlands)

    Braga, Rodrigo M; Roze, Elise; Ball, Gareth; Merchant, Nazakat; Tusor, Nora; Arichi, Tomoki; Edwards, David; Rueckert, Daniel; Counsell, Serena J

    2015-01-01

    White matter tracts mature asymmetrically during development, and this development can be studied using diffusion magnetic resonance imaging. The aims of this study were i. to generate dynamic population-averaged white matter registration templates covering in detail the period from 25 weeks

  9. Cortical involvement of marchiafava-bignami disease: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Han Won [Yeungnam University College of Medicine, Daegu (Korea, Republic of)

    2007-03-15

    Marchiafava-Bignami disease is a rare complication of chronic alcoholism and this malady typically manifests as callosal lesion. I report here on one patient with Marchiafava-bignami disease (MBD) who has symmetric restricted diffusion in both lateral-frontal cortices, in addition to the callosal lesion.

  10. Positive correlations between corpus callosum thickness and intelligence.

    Science.gov (United States)

    Luders, Eileen; Narr, Katherine L; Bilder, Robert M; Thompson, Paul M; Szeszko, Philip R; Hamilton, Liberty; Toga, Arthur W

    2007-10-01

    Callosal morphology is thought to reflect the capacity for inter-hemispheric communication and thus, in addition to other cerebral characteristics, may serve as a neuroanatomical substrate of general intellectual capacity. We applied novel computational mesh-based methods to establish the presence and direction of correlations between intelligence and callosal thickness at high spatial resolution while removing the variance associated with overall brain size. Within healthy subjects (n=62), and within males (n=28) and females (n=34) separately, we observed significant positive correlations between callosal morphology and intelligence measures (full-scale, performance, and verbal). These relationships were pronounced in posterior callosal sections and were confirmed by permutation testing. Significant negative correlations were absent. Positive associations between intelligence and posterior callosal thickness may reflect a more efficient inter-hemispheric information transfer, positively affecting information processing and integration, and thus intellectual performance. At the same time, regional variations in callosal size might also partly reflect the underlying architecture of topographically connected cortical regions relevant for processing higher-order cognitive information. Our findings emphasize the importance of incorporating posterior (callosal) regions into the theories and models proposed to explain the anatomical substrates of intelligence.

  11. When more is less: associations between corpus callosum size and handedness lateralization

    Science.gov (United States)

    Luders, Eileen; Cherbuin, Nicolas; Thompson, Paul M.; Gutman, Boris; Anstey, Kaarin J.; Sachdev, Perminder; Toga, Arthur W.

    2010-01-01

    Although not consistently replicated, a substantial number of studies suggest that left-handers have larger callosal regions than right-handers. We challenge this notion and propose that callosal size is not linked to left-handedness or right-handedness per se but to the degree of handedness lateralization. To test this hypothesis, we investigated the thickness of the corpus callosum in a large data set (n=361). We analyzed the correlations between callosal thickness and the degree of handedness lateralization in 324 right-handers and 37 left-handers at 100 equidistant points across the corpus callosum. We revealed significant negative correlations within the anterior and posterior midbody suggesting that larger callosal dimensions in these regions are associated with a weaker handedness lateralization. Significant positive correlations were completely absent. In addition, we compared callosal thickness between moderately lateralized left-handers (n=37) and three equally sized groups (n=37) of right-handers (strongly, moderately, and weakly lateralized). The outcomes of these group analyses confirmed the negative association between callosal size and handedness lateralization, although callosal differences between right- and left-handers did not reach statistical significance. This suggests that callosal differences are rather small, if examined as a dichotomy between two handedness groups. Future studies will expand this line of research by increasing the number of left-handers to boost statistical power, and by combining macro- and micro-structural, as well as functional and behavioral measurements to identify the biological mechanisms linking callosal morphology and handedness lateralization. PMID:20394828

  12. Reference: 201 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available un et al. 2005 May. Plant J. 42(3):315-28. Callose (beta-1,3-glucan) is produced at different locations in re...strate that one of these genes, CalS5, encodes a callose synthase which is respon...sible for the synthesis of callose deposited at the primary cell wall of meiocytes, tetrads and microspores, and the expre...ane protein of 1923 amino acid residues with a molecular mass of 220 kDa. Knockou...t mutations of the CalS5 gene by T-DNA insertion resulted in a severe reduction in fertility. The reduced fe

  13. Interhemispheric connections between primary visual areas: beyond the midline rule

    Directory of Open Access Journals (Sweden)

    Houzel J.-C.

    2002-01-01

    Full Text Available In the last five years, a number of detailed anatomical, electrophysiological, optical imaging and simulation studies performed in a variety of non-human species have revealed that the functional organization of callosal connections between primary visual areas is more elaborate than previously thought. Callosal cell bodies and terminals are clustered in columns whose correspondence to features mapped in the visual cortex, such as orientation and ocularity, are starting to be understood. Callosal connections are not restricted to the vertical midline representation nor do they establish merely point-to-point retinotopic correspondences across the hemispheres, as traditionally believed. In addition, anatomical studies have revealed the existence of an ipsilateral component of callosal axons. The aim of this short review is to propose how these new data can be integrated into an updated scheme of the circuits responsible for assembling the primary visual field map.

  14. [The size of cells providing interhemispheric and intrahemispheric connections in the visual cortex of binocular vision-impaired cats].

    Science.gov (United States)

    Alekseenko, S V; Toporova, S N; Shkorbatova, P Iu

    2011-03-01

    The size (somatic area) of 658 cells located in layers 2/3 of cortical areas 17, 18 of both hemispheres in intact monocularly deprived and bilateral strabismic cats was measured. These cells were retrogradely labelled after injections of horseradish peroxidase into ocular dominance columns in areas 17, 18. In all groups of cats, the mean somatic area of callosal cells was significantly larger than the mean somatic area of intrahemispheric cells. It was found that the mean somatic area of callosal cells was increased by 26.6% in monocularly deprived cats and by 20.2% in strabismic cats in relation to the mean somatic area of callosal cells in intact cats. In addition, the mean somatic area of intrahemispheric cells in monocularly deprived cats was indistinguishable from the mean somatic area of intrahemispheric cells in strabismic cats and in intact cats. It is concluded that early binocular vision impairments produce enlargement of callosal cells' size in the visual cortex.

  15. Reference: 58 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ion of callosic plugs, or papillae, at sites of fungal penetration is a widely recognized early response of ...e from papillae in gsl5 plants marginally enhanced the penetration of the grass p

  16. Glucosinolate Metabolites Required for an Arabidopsis Innate Immune Response*

    Science.gov (United States)

    Clay, Nicole K.; Adio, Adewale M.; Denoux, Carine; Jander, Georg; Ausubel, Frederick M.

    2008-01-01

    Summary The perception of pathogen or microbe-associated molecular pattern molecules by plants triggers a basal defense response analogous to animal innate immunity, and is defined in part by the deposition of the glucan polymer callose at the cell wall at the site of pathogen contact. Transcriptional and metabolic profiling in Arabidopsis mutants, coupled with the monitoring of pathogen triggered callose deposition, have identified major roles in pathogen response for the plant hormone ethylene and the secondary metabolite 4-methoxy-indol-3-ylmethylglucosinolate. Two genes, PEN2 and PEN3, are also necessary for resistance to pathogens and are required for both callose deposition and glucosinolate activation, suggesting that the pathogen triggered callose response is required for resistance to microbial pathogens. Our study shows that well-studied plant metabolites, previously identified as important in avoiding damage by herbivores, are also required as a component of the plant defense response against microbial pathogens. PMID:19095898

  17. Glucosinolate metabolites required for an Arabidopsis innate immune response.

    Science.gov (United States)

    Clay, Nicole K; Adio, Adewale M; Denoux, Carine; Jander, Georg; Ausubel, Frederick M

    2009-01-02

    The perception of pathogen or microbe-associated molecular pattern molecules by plants triggers a basal defense response analogous to animal innate immunity and is defined partly by the deposition of the glucan polymer callose at the cell wall at the site of pathogen contact. Transcriptional and metabolic profiling in Arabidopsis mutants, coupled with the monitoring of pathogen-triggered callose deposition, have identified major roles in pathogen response for the plant hormone ethylene and the secondary metabolite 4-methoxy-indol-3-ylmethylglucosinolate. Two genes, PEN2 and PEN3, are also necessary for resistance to pathogens and are required for both callose deposition and glucosinolate activation, suggesting that the pathogen-triggered callose response is required for resistance to microbial pathogens. Our study shows that well-studied plant metabolites, previously identified as important in avoiding damage by herbivores, are also required as a component of the plant defense response against microbial pathogens.

  18. Agenesis of the corpus callosum with associated inter-hemispheric ...

    African Journals Online (AJOL)

    Adele

    childhood behavioural disorders, bipolar disorders,. Asperger's syndrome, personality disorder and conversion symptoms.1 Suspected causes of corpus callosum agenesis include chromosomal defects, prenatal infections, toxins and metabolic disorders.1 Callosal agenesis has been associated with interhemispheric cysts ...

  19. Aluminium localization and toxicity symptoms related to root growth ...

    Indian Academy of Sciences (India)

    2012-10-26

    . Its deposition is considered .... to avoid wound callose formation. After this period the first centimeter of the root tip .... Physiological injuries triggered by Al3+ stress are closely dependent on membrane injury (Matsumoto et al ...

  20. Reference: 759 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available re) plasma membrane plays multiple roles in pollen wall development, including callose secretion, primexine deposition...nt at the tetrad stage, which leads to defective sporopollenin deposition on microspores and the locule wall

  1. Reference: 63 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available on and tube growth, which are associated with abnormal callose deposition. This finding suggests an essentia...l role for GPI anchor biosynthesis in pollen tube wall deposition or metabolism. Using transcriptomic and pr

  2. Lipoma of corpus callosum associated with dysraphic lesions and trisomy 13

    Energy Technology Data Exchange (ETDEWEB)

    Wainwright, H.; Bowen, R.; Radcliffe, M. [Univ. of Cape Town Medical School (South Africa)

    1995-05-22

    We report on a further case of corpus callosal lipoma and frontal cranial defects. Most cases in the literature of corpus callosal lipoma in association with {open_quotes}dysraphic{close_quotes} lesions have been frontal in location. Malformation of the corpus callosum is said to be associated with 50% of these lipomas. Trisomy 13 was confirmed by the 13q14 cosmid probe on paraffin-embedded liver tissue. 19 refs., 5 figs.

  3. Occupational dermatoses in Beedi rollers

    OpenAIRE

    Kuruvila Maria; Mukhi Sanjay; Kumar Pramod; Rao Gatha; Sridhar K; Kotian M

    2002-01-01

    A total of 91 beedi workers were analyzed for the pattern of cutaneous lesions. Period of rolling beedi ranged from 2 months to 40 years. Dermatological findings included; callosities seen in 51 (56.04%) of workers on fingers and feet, nail changes in 22 (24.18%) like pigmentation, paronychia, dystrophy which were more prominent on the right index finger, fungal infections in 15 and eczemas in 29. Callosities and localised nail changes can be considered to be occupational marks ...

  4. Positive Correlations between Corpus Callosum Thickness and Intelligence

    OpenAIRE

    Luders, Eileen; Narr, Katherine L; Bilder, Robert M.; Paul M. Thompson; Szeszko, Philip R.; Hamilton, Liberty; Toga, Arthur W.

    2007-01-01

    Callosal morphology is thought to reflect the capacity for inter-hemispheric communication and thus, in addition to other cerebral characteristics, may serve as a neuroanatomical substrate of general intellectual capacity. We applied novel computational mesh-based methods to establish the presence and direction of correlations between intelligence and callosal thickness at high spatial resolution while removing the variance associated with overall brain size. Within healthy subjects (n=62), a...

  5. Asymmetrical interhemispheric connections develop in cat visual cortex after early unilateral convergent strabismus: Anatomy, physiology and mechanisms

    Directory of Open Access Journals (Sweden)

    Emmanuel eBui Quoc

    2012-01-01

    Full Text Available In the mammalian primary visual cortex, the corpus callosum contributes to the unification of the visual hemifields that project to the two hemispheres. Its development depends on visual experience. When the latter is abnormal, callosal connections must undergo dramatic anatomical and physiological changes. However, such data are sparse and incomplete. Thus, little is known about the consequences of abnormal postnatal visual experience on the development of callosal connections and their role in unifying representation of the two hemifields. Here, the effects of early unilateral convergent strabismus (a model of abnormal visual experience were fully characterized with respect to the development of the callosal connections in cat visual cortex, an experimental model for humans. Electrophysiological responses and 3D reconstruction of single callosal axons show that abnormally asymmetrical callosal connections develop after unilateral convergent strabismus, resulting from an extension of axonal branches of specific orders in the hemisphere ipsilateral to the deviated eye and a decreased number of nodes and terminals in the other (ipsilateral to the non deviated eye. Furthermore this asymmetrical organization prevents the establishment of a unifying representation of the two visual hemifields. As a general rule, we suggest that crossed and uncrossed retino-geniculo-cortical pathways contribute in succession to the development of the callosal maps in visual cortex.

  6. Evaluation of histopathologic changes in an animal model of mechanical corpus callosum impingement as seen in hydrocephalus.

    Science.gov (United States)

    Jinkins, J R; Rauch, R A; Hagino, N; Kagan-Hallet, K S; Xiong, L

    1995-07-01

    We evaluated histologic changes associated with chronic impingement of the corpus callosum. Similar callosal impingement has been postulated to be responsible for some of the symptoms in people who have hydrocephalus. Eight rats with callosal impingement produced by surgical implantation of a blunt blade in the interhemispheric fissure and four control animals with no callosal impingement were evaluated by magnetic resonance (MR) imaging and by direct histologic evaluation after autopsy. The histologic evaluations occurred 1 month after surgery in half the animals and 6 months after surgery in the other half. MR imaging results showed that the implanted blade was in a good position in all animals. Histologically, the corpus callosum appeared normal 1 month after implantation of the impingement blade. Six months after surgery, the experimental group demonstrated decreased callosal thickness and a loss of axonal fibers in the corpus callosum both near and remote to the blade. Chronic impingement of the corpus callosum was associated with callosal thinning and by loss of callosal axons. Further research will be required to investigate the possible relation of these histologic findings to the clinical findings in normal-pressure hydrocephalus.

  7. New insight into silica deposition in horsetail (Equisetum arvense

    Directory of Open Access Journals (Sweden)

    Exley Christopher

    2011-07-01

    Full Text Available Abstract Background The horsetails (Equisetum sp are known biosilicifiers though the mechanism underlying silica deposition in these plants remains largely unknown. Tissue extracts from horsetails grown hydroponically and also collected from the wild were acid-digested in a microwave oven and their silica 'skeletons' visualised using the fluor, PDMPO, and fluorescence microscopy. Results Silica deposits were observed in all plant regions from the rhizome through to the stem, leaf and spores. Numerous structures were silicified including cell walls, cell plates, plasmodesmata, and guard cells and stomata at varying stages of differentiation. All of the major sites of silica deposition in horsetail mimicked sites and structures where the hemicellulose, callose is known to be found and these serendipitous observations of the coincidence of silica and callose raised the possibility that callose might be templating silica deposition in horsetail. Hydroponic culture of horsetail in the absence of silicic acid resulted in normal healthy plants which, following acid digestion, showed no deposition of silica anywhere in their tissues. To test the hypothesis that callose might be templating silica deposition in horsetail commercially available callose was mixed with undersaturated and saturated solutions of silicic acid and the formation of silica was demonstrated by fluorimetry and fluorescence microscopy. Conclusions The initiation of silica formation by callose is the first example whereby any biomolecule has been shown to induce, as compared to catalyse, the formation of silica in an undersaturated solution of silicic acid. This novel discovery allowed us to speculate that callose and its associated biochemical machinery could be a missing link in our understanding of biosilicification.

  8. Cation-induced formation of a macro-glucan synthase complex

    Energy Technology Data Exchange (ETDEWEB)

    Delmer, D.; Solomon, M.; Andrawis, A.; Amor, Y. (Hebrew Univ., Jerusalem (Israel))

    1990-05-01

    Incubation of Chaps or digitonin-solubilized membrane proteins from cotton fiber with Ca{sup 2+} in combination with Mg{sup 2+}, leads to formation of a complex which can be sedimented within 15 min at 15,000 g. The complex is enriched >10-fold in callose synthase activity and possesses a characteristic pattern of enriched polypeptides when analyzed by SDS-PAGE. Although cation dependent, formation of the complex is not dependent upon the presence of the callose synthase substrate, UDP-glc, indicating that complex formation is not due to entrapment of the enzyme by association with glucan product. The enriched polypeptides include: >200, 50, and 46 kD, all of which have been shown by direct photo-labeling to interact with {sup 92}P-UDP-glc in a Ca{sup 2+} or beta-glucoside dependent reaction are considered likely subunits of callose synthase; a 60-62 kD doublet which is recognized by our MAb 2-1 which can form an immune complex with callose synthase; 74 and 34 kD polypeptides which also interact with UDP-glc, but do not associate with callose synthase in the presence of EDTA. A similar phenomenon is also observed with solubilized membrane proteins from mung beans. Possible functions of each of the enriched polypeptides, the catalytic properties, and ultra-structure of this macro-glucan synthase complex are currently under investigation.

  9. Interhemispheric Transfer in Down’s Syndrome

    Directory of Open Access Journals (Sweden)

    C. M. J. Braun

    1992-01-01

    Full Text Available Callosal agenesics and callosotomized epileptics manifest markedly increasing simple visual reaction time (SVRT from conditions of ipsilateral to contralateral stimulus-response relation (SRR. In the contralateral SRR, a response is presumed possible because of presence of other commissures (anterior, intercollicular. The SRR effect is prolonged presumably because the remaining commissures are less efficient than the corpus callosum in relaying necessary visual or motor information. Consequently, the SRR effect is believed to correspond to callosal relay time (CRT in the normal subject. However, both callosal agenesics and callosotomy patients manifest general slowing of SVRT in addition to a prolonged SRR effect. These patients have massive extra-callosal damage which could plausibly cause both the SVRT and the CUD prolongation. If such were the case, the CRT inference would be in jeopardy. A test of the CRT inference is therefore required where patients with massive diffuse extra-callosal brain damage and normal callosi would show marked general SVRT prolongation and a normal SRR effect. Four trisomy-21 (T21 males were compared to age and sex-matched normal controls. General SVRT was highly significantly prolonged in T21, but the CUD was nearly identical in both groups.

  10. Automated measurement of the human corpus callosum using MRI

    Directory of Open Access Journals (Sweden)

    Timothy J Herron

    2012-09-01

    Full Text Available The corpus callosum includes the majority of fibers that connect the two cortical hemispheres. Studies of cross-sectional callosal morphometry and area have revealed developmental, gender, and hemispheric differences in healthy populations and callosal deficits associated with neurodegenerative disease and brain injury. However, accurate quantification of the callosum using magnetic resonance imaging is complicated by intersubject variability in callosal size, shape, and location and often requires manual outlining of the callosum in order to achieve adequate performance. Here we describe an objective, fully automated protocol that utilizes voxel-based image to quantify the area and thickness both of the entire callosum and of different callosal compartments. We verify the method’s accuracy, reliability, robustness and multisite consistency and make comparisons with manual measurements using public brain-image databases. An analysis of age-related changes in the callosum showed increases in length and reductions in thickness and area with age. A comparison of older subjects with and without mild dementia revealed that reductions in anterior callosal area independently predicted poorer cognitive performance after factoring out Mini-Mental Status Examination scores and normalized whole brain volume. Open-source software implementing the algorithm is available at www.nitrc.org/projects/c8c8.

  11. A cascade of morphogenic signaling initiated by the meninges controls corpus callosum formation

    Science.gov (United States)

    Choe, Youngshik; Siegenthaler, Julie A.; Pleasure, Samuel J.

    2012-01-01

    Summary The corpus callosum is the most prominent commissural connection between the cortical hemispheres, and numerous neurodevelopmental disorders are associated with callosal agenesis. Using mice with either meningeal overgrowth or selective loss of meninges, we’ve identified a cascade of morphogenic signals initiated by the meninges that regulates corpus callosum development. The meninges produce BMP7, an inhibitor of callosal axon outgrowth. This activity is overcome by the induction of expression of Wnt3 by the callosal pathfinding neurons, which antagonizes the inhibitory effects of BMP7. Wnt3 expression in the cingulate callosal pathfinding axons is developmentally regulated by another BMP family member, GDF5, produced by the adjacent Cajal-Retzius neurons and turns on before outgrowth of the callosal axons. The effects of GDF5 are in turn under the control of a soluble GDF5 inhibitor, Dan, made by the meninges. Thus, the meninges and medial neocortex use a cascade of signals to regulate corpus callosum development. PMID:22365545

  12. Mutual regulation between Satb2 and Fezf2 promotes subcerebral projection neuron identity in the developing cerebral cortex.

    Science.gov (United States)

    McKenna, William L; Ortiz-Londono, Christian F; Mathew, Thomas K; Hoang, Kendy; Katzman, Sol; Chen, Bin

    2015-09-15

    Generation of distinct cortical projection neuron subtypes during development relies in part on repression of alternative neuron identities. It was reported that the special AT-rich sequence-binding protein 2 (Satb2) is required for proper development of callosal neuron identity and represses expression of genes that are essential for subcerebral axon development. Surprisingly, Satb2 has recently been shown to be necessary for subcerebral axon development. Here, we unravel a previously unidentified mechanism underlying this paradox. We show that SATB2 directly activates transcription of forebrain embryonic zinc finger 2 (Fezf2) and SRY-box 5 (Sox5), genes essential for subcerebral neuron development. We find that the mutual regulation between Satb2 and Fezf2 enables Satb2 to promote subcerebral neuron identity in layer 5 neurons, and to repress subcerebral characters in callosal neurons. Thus, Satb2 promotes the development of callosal and subcerebral neurons in a cell context-dependent manner.

  13. [LAMINAR LOCATION OF NEURONS PROVIDING INTERHEMISPHERIC CONNECTIONS IN THE VISUAL CORTEX IN CATS WITH IMPAIRMENTS OF BINOCULAR VISION].

    Science.gov (United States)

    Toporova, S N; Shkorbatova, P Yu; Alekseyenko, S V

    2015-01-01

    The distributio of cells in the visual cortical layers of intact cats (n=7) and cats with experimentally induced strabismus (n=10) and monocular deprivation (n=5) was studied after microiontophoretic injection of horseradish peroxidase into the ocular-dominance columns in areas 17, 18 and the transition zone 17/18. It was found that in cats with impaired binocular vision, the callosal cells were located deeper in layers of I/II, and higher - in layer IV, as compared to those in intact cats. Also in cats with impaired binocular vision, the proportion of callosal cells in layer IV was increased, while in layers II/III it was reduced as compared to intact cats. The most pronounced changes were noted in monocular deprived animals. These findings suggest an important role of sensory input in the formation of the callosal neurons layer distribution.

  14. [Interhemispheric connections of ocular-dominance columns in cats with binocular vision impairment].

    Science.gov (United States)

    Alekseenko, S V; Toporova, S N; Shkorbatova, P Iu

    2008-06-01

    We have investigated the interhemispheric connections of areas 17 and 18 in cats with impaired binocular vision (monocular deprivation, uni- and bilateral strabismus). Monosynaptic neuronal connections were studied using microionophoretic injections of horseradish peroxidase in the single cortical columns and analsys of spatial distribution of retrogradely labelled callosal cells was performed. In the cases of monocular deprivation and strabismus, the spatial asymmetry and eye-specificity of interhemispheric connections are retained. Quantitative changes of connections are more pronounced in strabismic cats. In cats with binocular vision impairments, as well as in control ones, the width of callosal-recipient zone is larger than of the callosal cells zone. This may indicate that interhemispheric connections are non-reciprocal in the areas of cortex that are more distant from the projection of vertical meridian of visual field. We expect that there should be morpho-functional in the cells that are providing connections in opposite directions.

  15. Netrin-DCC signaling regulates corpus callosum formation through attraction of pioneering axons and by modulating Slit2-mediated repulsion.

    Science.gov (United States)

    Fothergill, Thomas; Donahoo, Amber-Lee S; Douglass, Amelia; Zalucki, Oressia; Yuan, Jiajia; Shu, Tianzhi; Goodhill, Geoffrey J; Richards, Linda J

    2014-05-01

    The left and right sides of the nervous system communicate via commissural axons that cross the midline during development using evolutionarily conserved molecules. These guidance cues have been particularly well studied in the mammalian spinal cord, but it remains unclear whether these guidance mechanisms for commissural axons are similar in the developing forebrain, in particular for the corpus callosum, the largest and most important commissure for cortical function. Here, we show that Netrin1 initially attracts callosal pioneering axons derived from the cingulate cortex, but surprisingly is not attractive for the neocortical callosal axons that make up the bulk of the projection. Instead, we show that Netrin-deleted in colorectal cancer signaling acts in a fundamentally different manner, to prevent the Slit2-mediated repulsion of precrossing axons thereby allowing them to approach and cross the midline. These results provide the first evidence for how callosal axons integrate multiple guidance cues to navigate the midline.

  16. Traumatic callosotomy

    Directory of Open Access Journals (Sweden)

    Arthur Cukiert

    1992-09-01

    Full Text Available In a 33 years-old epileptic woman with a traumatic impact to the vertex, clinical and radiological studies (skull X-R, CT and MRI disclosed an extensive, callosal section under the topography of the falx, associated to frontonasal contusions. There was a significant improvement in the epileptic syndrome. No interhemispheric disconnection syndrome could be determined, which is compatible with the posterior regions of the corpus callosum having been spared. This is, to the best of our knowledge, the most extensive callosal injury documented by MRI to date.

  17. Occupational dermatoses in Beedi rollers

    Directory of Open Access Journals (Sweden)

    Kuruvila Maria

    2002-01-01

    Full Text Available A total of 91 beedi workers were analyzed for the pattern of cutaneous lesions. Period of rolling beedi ranged from 2 months to 40 years. Dermatological findings included; callosities seen in 51 (56.04% of workers on fingers and feet, nail changes in 22 (24.18% like pigmentation, paronychia, dystrophy which were more prominent on the right index finger, fungal infections in 15 and eczemas in 29. Callosities and localised nail changes can be considered to be occupational marks in beedi rollers correlated to use of scissors for cutting leaves and use of gum and artificial metallic nails for rolling beedis.

  18. Ca2+-mediated remote control of reversible sieve tube occlusion in Vicia faba

    DEFF Research Database (Denmark)

    Furch, Alexandra C.U.; Hafke, Jens B.; Schulz, Alexander

    2007-01-01

    (EPWs), and is reversible in intact plants. The time-course of the wound response was studied in sieve elements of main veins of intact Vicia faba plants using confocal and multiphoton microscopy. Only 15-45 s after burning a leaf tip, forisomes (giant protein bodies specific for legume sieve tubes...... reversible; callose degraded over the subsequent 1-2 h. The heat induction of both modes of occlusion coincided with the passage of an EPW visualized by electrophysiology or the potential-sensitive dye RH-414. In contrast to burning, cutting of the leaf tip induced neither an EPW nor callose deposition...

  19. Occupational dermatoses in beedi rollers.

    Science.gov (United States)

    Kuruvila, Maria; Mukhi, Sanjay V; Kumar, Pramod; Rao, Gatha S; Sridhar, K S; Kotian, M S

    2002-01-01

    A total of 91 beedi workers were analyzed for the pattern of cutaneous lesions. Period of rolling beedi ranged from 2 months to 40 years. Dermatological findings included; callosities seen in 51 (56.04%) of workers on fingers and feet, nail changes in 22 (24.18%) like pigmentation, paronychia, dystrophy which were more prominent on the right index finger, fungal infections in 15 and eczemas in 29. Callosities and localised nail changes can be considered to be occupational marks in beedi rollers correlated to use of scissors for cutting leaves and use of gum and artificial metallic nails for rolling beedis.

  20. Al-induced root cell wall chemical components differences of wheat ...

    African Journals Online (AJOL)

    Jane

    2011-07-13

    Jul 13, 2011 ... Key words: Aluminum toxicity, callose, cellulose, hydrogen peroxide, lignin, wheat. INTRODUCTION. Ionic aluminum (Al) in acid soils is toxic to most plant species at micromolar concentrations. .... g for 20 min at 4°C. For peroxidase assay,. 3.8 ml of the assay mixture contained 80 mM phosphate buffer (pH ...

  1. The role of Δ1-pyrroline-5-carboxylate dehydrogenase in proline degradation

    DEFF Research Database (Denmark)

    Deuschle, Karen; Funck, Dietmar; Forlani, Giuseppe

    2004-01-01

    growth. External Pro application caused programmed cell death, with callose deposition, reactive oxygen species production, and DNA laddering, involving a salicylic acid signal transduction pathway. p5cdh mutants were hypersensitive toward Pro and other molecules producing P5C, such as Arg and Orn. Pro...

  2. Corpus callosum size correlates with asymmetric performance on a dichotic listening task in healthy aging but not in Alzheimer's disease

    NARCIS (Netherlands)

    Gootjes, L; Bouma, A; Van Strien, JW; Van Schijndel, R; Barkhof, F; Scheltens, P

    2006-01-01

    Alzheimer's disease (AD) involves not only gray matter but also white matter pathology, as reflected by atrophy of the corpus callosum (CC). Since decreased CC size may indicate reduced functional interhemispheric connectivity, differences in callosal size may have cognitive consequences that may

  3. Corpus callosum size correlates with asymmetric performance on a dichotic listening task in healthy aging but not in Alzheimer's disease

    NARCIS (Netherlands)

    L. Gootjes (Liselotte); A. Bouma (Anke); J.W. van Strien (Jan); R. van Schijndel; F. Barkhof (Frederik); P. Scheltens (Philip)

    2008-01-01

    textabstractAlzheimer's disease (AD) involves not only gray matter but also white matter pathology, as reflected by atrophy of the corpus callosum (CC). Since decreased CC size may indicate reduced functional interhemispheric connectivity, differences in callosal size may have cognitive consequences

  4. Corpus callosum atrophy in patients with mild Alzheimer's disease

    DEFF Research Database (Denmark)

    Frederiksen, Kristian Steen; Garde, Ellen; Skimminge, Arnold

    2011-01-01

    Several studies have found atrophy of the corpus callosum (CC) in patients with Alzheimer's disease (AD). However, it remains unclear whether callosal atrophy is already present in the early stages of AD, and to what extent it may be associated with other structural changes in the brain, such as ...

  5. Natural markings and their use in determining calving intervals in ...

    African Journals Online (AJOL)

    Since 1979, 245 right whales (excluding calves) have been individually identified in aerial photographs taken annually on the South African coast, using variations in dorsal pigmentation and callosity patterns. White or grey blazes (or both) occurred dorsally in 16,7% of individuals, one form of which (partial albinism) ...

  6. Identification of plant defence regulators through transcriptional

    Indian Academy of Sciences (India)

    Through bacterial resistance, callose deposition and pathogenesis-associated expression analyses, we identified four novel regulators of plant defence. Resistance levels in the mutants suggest that At2g19810 and [rom] At5g05790 are positive regulators, whereas At1g61370 and At3g42790 are negative regulators of plant ...

  7. Seed germination and in vitro plant regeneration of Parkia biglobosa ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-05-24

    May 24, 2010 ... Indeed, Zimmerman and Brome (1980) noted that the rooting can be obtained in a solid medium or for better results, in a liquid medium. Villegas (1992) used the rootstock M106, a solid and liquid medium with paper as support and obtained an excessive development of callosity with 40% of rooting in the ...

  8. Reference: 204 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ified in Arabidopsis based on a growth defect of the dark-grown hypocotyl and an abnormal composition of the...on defects of cells in the central cylinder. These defects were accompanied by changes in the non-cellulosic polysaccharide compositi...on, including the accumulation of ectopic callose. Interestingly, in contrast to ot

  9. UJAS 2.pmd

    African Journals Online (AJOL)

    ACSS

    Musa balbisiana resists Xanthomonas wilt disease through multiplication of Xvm transduction cascades that turn on basal defense mechanisms such as callose and silicone deposition to reinforce the cell wall, closure of stomata, production of reactive oxygen species, transcriptional induction of pathogenesis-related genes.

  10. Aluminium localization and toxicity symptoms related to root growth ...

    Indian Academy of Sciences (India)

    Neutral invertase enzyme activity and callose (1 → 3, -D-glucan) accumulation were observed and compared with Al3+ accumulation sites. Root growth was inhibited by Al3+ in a concentration-specific manner and proportional to the increase of hematoxylin staining, being more pronounced in the sensitive genotype.

  11. Descriptions of new Cetoniidae

    NARCIS (Netherlands)

    Janson, Oliver E.

    1888-01-01

    Testaceous red, shining; head black; elytra with a broad pale greenish yellow longitudinal band at the sides, the lateral margin at the shoulder and humeral callosity black; mesosternal process, anterior and intermediate tibiae and posterior knees piceous; tarsi black. — Length 21 mm. Very

  12. A computerized approach for morphological analysis of the corpus callosum

    Energy Technology Data Exchange (ETDEWEB)

    Davatzikos, C.; Vaillant, M.; Letovsky, S.; Bryan, R.N.; Prince, J.L. [Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States); Resnick, S.M. [National Inst. of Aging, Baltimore, MD (United States)

    1996-01-01

    A new technique for analyzing the morphology of the corpus callosum is presented, and it is applied to a group of elderly subjects. The proposed approach normalizes subject data into the Talairach space using an elastic deformation transformation. The properties of this transformation are used as a quantitative description of the callosal shape with respect to the Talairach atlas, which is treated as a standard. In particular, a deformation function measures the enlargement/shrinkage associated with this elastic deformation. Intersubject comparisons are made by comparing deformation functions. This technique was applied to eight male and eight female subjects. Based on the average deformation functions of each group, the posterior region of the female corpus callosum was found to be larger than its corresponding region in the males. The average callosal shape of each group was also found, demonstrating visually the callosal shape differences between the two groups in this sample. The proposed methodology utilizes the full resolution of the data, rather than relying on global descriptions such as area measurements. The application of this methodology to an elderly group indicated sex-related differences in the callosal shape and size. 29 refs., 16 figs.

  13. Natural markings and their use in determining calving intervals in ...

    African Journals Online (AJOL)

    1987-10-06

    Oct 6, 1987 ... 3,6% of the calves born but may be sex linked. In 19 animals carrying dorsal marks that were ..... effects on the rate of water flow these callosities are frequently associated with large numbers of ..... therefore, this might result in the recognition of fewer calving intervals and (if the changes are reversed.

  14. Recovery from stolbur disease in grapevine involves changes in sugar transport and metabolism

    Directory of Open Access Journals (Sweden)

    Simonetta eSanti

    2013-06-01

    Full Text Available Grapevine can be severely affected by phytoplasmas, which are phytopathogenic Mollicutes invading the sieve elements of the host plant. The biochemical and molecular relationships between phytoplasmas and their hosts remain largely unexplored. Equally unknown is an interesting aspect of the pathogen-plant interaction called 'recovery', which is a spontaneous remission of symptoms in previously symptomatic plants. Recovered plants develop resistance mechanisms correlated with ultrastructural and biochemical changes in the sieve elements. Callose as well as sugars are involved in several plant defense processes and signaling. In the present work we have examined the possible involvement of callose, as well as callose synthase, sugar transporter, and cell wall invertase genes, during the infection and after ‘recovery’ of grapevine from Bois Noir (BN. Ultrastructural investigation of leaf tissue showed that callose accumulated in the sieve elements of diseased grapevine; moreover, two genes encoding for callose synthase were up-regulated in the infected leaves. Regarding sucrose, expression analysis showed that sucrose transport and cleavage were severely affected by BN phytoplasma, which induced the establishment of a carbohydrate sink in the source leaf, and was analogous to other obligate biotrophs that acquire most of their nutrients from the host plant. Interestingly, whereas in recovered plants the transcript level of sucrose synthase was similar to healthy plants, sucrose transporters as well as cell wall invertase were expressed to a greater degree in recovered leaves than in healthy ones. Recovered plants seem to acquire structural and molecular changes leading to increases in sucrose transport ability and defense signaling.

  15. Adults with attention-deficit/hyperactivity disorder - A diffusion-tensor imaging study of the corpus callosum

    DEFF Research Database (Denmark)

    Dramsdahl, Margaretha; Westerhausen, René; Haavik, Jan

    2012-01-01

    The objective of the present study was to investigate the microstructure and the macrostructure of the corpus callosum (CC) in adults with Attention-Deficit/Hyperactivity Disorder (ADHD) by means of magnetic resonance imaging (MRI). Twenty-nine participants with ADHD and 37 controls were included...... to the control group, whereas the size of the CC did not differ across groups. Our findings thus demonstrate a divergence between microstructural and macrostructural measures in the CC of adults with ADHD. This contrasts with findings in children demonstrating callosal abnormalities in both microstructure...... and macrostructure. Our results may indicate that adults with ADHD in part have succeeded in passing by an earlier developmental delay of the CC, resulting in a normalization of callosal macrostructure into adulthood. However, microstructural differences are still present in adults, which may point to an abnormal...

  16. Risk factors for subclinical intramammary infection in dairy goats in two longitudinal field studies evaluated by Bayesian logistic regression

    DEFF Research Database (Denmark)

    Koop, Gerrit; Collar, Carol A.; Toft, Nils

    2013-01-01

    , caprine arthritis encephalitis-virus infection status, and kidding season), and uncontrollable risk factors (parity, lactation stage, milk yield, pregnancy status, and breed) were measured in the Dutch study, the Californian study or in both studies. Bayesian logistic regression models were constructed......Identification of risk factors for subclinical intramammary infections (IMI) in dairy goats should contribute to improved udder health. Intramammary infection may be diagnosed by bacteriological culture or by somatic cell count (SCC) of a milk sample. Both bacteriological culture and SCC...... (mostly Staphylococcus aureus) on bacteriological culture and as positive or negative for SCC (cut-off of 2000 x 10(3) cells/mL). Potentially controllable risk factors (udder conformation, teat size, teat shape, teat placement, teat-end shape, teat-end callosity thickness, teat-end callosity roughness...

  17. Influence of type I IFN signaling on anti-MOG antibody-mediated demyelination

    DEFF Research Database (Denmark)

    Berg, Carsten Tue; Khorooshi, Reza M. H.; Asgari, Nasrin

    2017-01-01

    -MOG antibody and mouse complement were stereotactically injected into the corpus callosum of wild-type and type I IFN receptor deficient mice (IFNAR1-KO) with and without pre-established experimental autoimmune encephalomyelitis (EAE). Results Anti-MOG induced complement-dependent demyelination in the corpus...... callosum of wild-type mice and did not occur in mice that received control IgG2a. Deposition of activated complement coincided with demyelination, and this was significantly reduced in IFNAR1-KO mice. Co-injection of anti-MOG and complement at onset of symptoms of EAE induced similar levels of callosal...... demyelination in wild-type and IFNAR1-KO mice. Conclusions Anti-MOG antibody and complement was sufficient to induce callosal demyelination, and pathology was dependent on type I IFN. Induction of EAE in IFNAR1-KO mice overcame the dependence on type I IFN for anti-MOG and complement-mediated demyelination....

  18. Action in Perception: Prominent Visuo-Motor Functional Symmetry in Musicians during Music Listening

    Science.gov (United States)

    Burunat, Iballa; Brattico, Elvira; Puoliväli, Tuomas; Ristaniemi, Tapani; Sams, Mikko; Toiviainen, Petri

    2015-01-01

    Musical training leads to sensory and motor neuroplastic changes in the human brain. Motivated by findings on enlarged corpus callosum in musicians and asymmetric somatomotor representation in string players, we investigated the relationship between musical training, callosal anatomy, and interhemispheric functional symmetry during music listening. Functional symmetry was increased in musicians compared to nonmusicians, and in keyboardists compared to string players. This increased functional symmetry was prominent in visual and motor brain networks. Callosal size did not significantly differ between groups except for the posterior callosum in musicians compared to nonmusicians. We conclude that the distinctive postural and kinematic symmetry in instrument playing cross-modally shapes information processing in sensory-motor cortical areas during music listening. This cross-modal plasticity suggests that motor training affects music perception. PMID:26422790

  19. Functional brain asymmetry, attentional modulation, and interhemispheric transfer in boys with Tourette syndrome

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Lundervold, Arvid; Grüner, Renate

    2007-01-01

    on the right ear stimulus in the dichotic listening situation is thought to involve the same prefrontal attentional and executive functions that are involved in the suppression of tics, whereas, performance when focusing attention on the left ear stimulus additionally involves a callosal transfer...... to shift attention normally when instructed to focus on the right ear stimulus. When instructed to focus attention on the left ear stimulus, however, performance deteriorated in the TS group. Correlations with CC area further supported the hypothesized presence of deviant callosal functioning in the TS......We tested the hypothesis that children with Tourette syndrome (TS) would exhibit aberrant brain lateralization compared to a healthy control (HC) group in an attention-modulation version of a verbal dichotic listening task using consonant-vowel syllables. The modulation of attention to focus...

  20. The complex history of the fronto-occipital fasciculus.

    Science.gov (United States)

    Schmahmann, Jeremy D; Pandya, Deepak N

    2007-01-01

    We investigated the history of the fronto-occipital fasciculus (FOF) and related tracts in the cerebral white matter because of their contemporary relevance for connectional neuroanatomy, magnetic resonance tractography, and clinical neurology. The term "FOF" originated with Forel and Onufrowicz who misidentified aberrant longitudinally oriented callosal fibers in patients with callosal agenesis. This error was soon recognized, and Dejerine described an actual FOF linking frontal and occipital lobes, but gross dissection and lesion-degeneration methods could not distinguish the FOF from the subcallosal fasciculus of Muratoff and neighboring white matter bundles. Subsequent descriptions of a probably nonexistent "inferior FOF" have led to the FOF being misnamed post-hoc "superior FOF," and other imprecise anatomical concepts and terminologies from the early literature are still perpetuated. Our analysis of brain fiber pathways using isotope anterograde tract tracers (Schmahmann & Pandya, 2006) resolves the earlier uncertainties and provides hypotheses regarding functions of these fiber pathways.

  1. Left leg apraxia after anterior cerebral artery territory infarction: functional analysis using single-photon emission computed tomography.

    Science.gov (United States)

    Ito, Ikuno; Ito, Kimiteru; Shindo, Naoko

    2013-01-01

    Left hand apraxia is known as a unique symptom of callosal apraxia, but lower limb symptoms are rarely mentioned. We report a patient who experienced left ideomotor apraxia affecting both the upper and lower limbs after a stroke in the territory of the right anterior cerebral artery. His spontaneous gait was normal, but he was unable to move his left leg intentionally either by verbal command or by imitation. His leg symptoms gradually improved over time. We evaluated the change in cerebral blood flow in this patient using single-photon emission computed tomography. The results showed an increase in blood flow in the posterior corpus callosum; therefore, we suggested that the callosal pathway might contribute to left leg as well as left hand volitional movement. Copyright © 2013 S. Karger AG, Basel.

  2. Polysaccharides and lipids in microsporocytes and tapetum of Rhoeo discolor Hance. Cytochemical study

    Directory of Open Access Journals (Sweden)

    Louis Albertini

    2014-01-01

    Full Text Available The present report, which mainly presents cytochemical results, establishes the determination, localisation and evolution of the cytoplasmic and wall polysaccharides and lipids in the microsporocytes and the plasmodial tape turn of Rhoeo discolor Hance. Enzymatic controls, use of autoradiographic methods, and electron microscopy, have proved the validity of our cytochemical results and permitted to precise these results. In the microsporocytes and pollen grains, the callosic special wall, the carotenoid exine, the pectocellulosic cellulasic in tine, and the callosic and pectic young curved wail. between the generative cell and the vegetative cell, have mainly held our attention. As for the tapetum which remains poor in insoluble polysacharides till the ultimate stages of microsporogenesis, it grows richer in choline - phospholipids during meiosis and, more lightly, in carotenoids beyond the tetrad stage; the periplasmodium does not seem to participate directly in the increase of exine lipids.

  3. Action in Perception: Prominent Visuo-Motor Functional Symmetry in Musicians during Music Listening.

    Directory of Open Access Journals (Sweden)

    Iballa Burunat

    Full Text Available Musical training leads to sensory and motor neuroplastic changes in the human brain. Motivated by findings on enlarged corpus callosum in musicians and asymmetric somatomotor representation in string players, we investigated the relationship between musical training, callosal anatomy, and interhemispheric functional symmetry during music listening. Functional symmetry was increased in musicians compared to nonmusicians, and in keyboardists compared to string players. This increased functional symmetry was prominent in visual and motor brain networks. Callosal size did not significantly differ between groups except for the posterior callosum in musicians compared to nonmusicians. We conclude that the distinctive postural and kinematic symmetry in instrument playing cross-modally shapes information processing in sensory-motor cortical areas during music listening. This cross-modal plasticity suggests that motor training affects music perception.

  4. Action in Perception: Prominent Visuo-Motor Functional Symmetry in Musicians during Music Listening.

    Science.gov (United States)

    Burunat, Iballa; Brattico, Elvira; Puoliväli, Tuomas; Ristaniemi, Tapani; Sams, Mikko; Toiviainen, Petri

    2015-01-01

    Musical training leads to sensory and motor neuroplastic changes in the human brain. Motivated by findings on enlarged corpus callosum in musicians and asymmetric somatomotor representation in string players, we investigated the relationship between musical training, callosal anatomy, and interhemispheric functional symmetry during music listening. Functional symmetry was increased in musicians compared to nonmusicians, and in keyboardists compared to string players. This increased functional symmetry was prominent in visual and motor brain networks. Callosal size did not significantly differ between groups except for the posterior callosum in musicians compared to nonmusicians. We conclude that the distinctive postural and kinematic symmetry in instrument playing cross-modally shapes information processing in sensory-motor cortical areas during music listening. This cross-modal plasticity suggests that motor training affects music perception.

  5. Dysgenesis of the corpus callosum and associated malformaaation{sup :} computed tomography and magnetic resonance imaging findings; Disgenesia do corpo caloso e mas-formacoes associadas: achados de tomografia computadorizada e ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Montandon, Cristiano; Montandon Junior, Marcelo Eustaquio [Colegio Brasileiro de Radiologia e Diagnostico por Imagem (CBR), Sao Paulo, SP (Brazil); Ribeiro, Flavia Aparecida de Sousa; Lobo, Leonardo Valadares Barbosa; Teixeira, Kim-Ir-Sen Santos [Goias Univ., Goiania (Brazil). Hospital de Clinicas. Dept. de Diagnostico por Imagem e Anatomia Patologica]. E-mail: cabeca2@terra.com.br

    2003-10-01

    Callosal dysgenesis is a malformation of the corpus callosum with origins in the embryogenesis of the telencephalon. We reviewed the computed tomography and magnetic resonance imaging findings of 11 patients with callosal dysgenesis and one patient with normal corpus callosum associated with a lipoma. The patients were divided into three distinct groups: total agenesis (three patients), partial agenesis (six patients) and hypoplasia (two patients). Associated abnormalities were observed in nine patients, including Chiari II malformation (one patient), schizencephaly (one patient), interhemispheric cyst (two patients), Dandy-Walker cyst (one patient), nodular heterotopy (one patient) and lipoma of the corpus callosum (four patients). This paper presents a review that may contribute to the diagnosis of these disorders. (author)

  6. The extracellular matrix of plants: Molecular, cellular and developmental biology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    A symposium entitled ``The Extracellular Matrix of Plants: Molecular, Cellular and Developmental Biology was held in Tamarron, Colorado, March 15--21, 1996. The following topics were explored in addresses by 43 speakers: structure and biochemistry of cell walls; biochemistry, molecular biology and biosynthesis of lignin; secretory pathway and synthesis of glycoproteins; biosynthesis of matrix polysaccharides, callose and cellulose; role of the extracellular matrix in plant growth and development; plant cell walls in symbiosis and pathogenesis.

  7. Occupational Dermatoses Among Kitchen Workers In A Chain Of Vegetarian Hotel

    Directory of Open Access Journals (Sweden)

    Rai Reena

    2003-01-01

    Full Text Available This study was undertaken to identify occupation related skin problems among hotel workers. One thousand three hindered and ninety employees of a chain of vegetarian hotels were examined. Of the 273 people working in the kitchen, 206 (75.4% had dermatosis related to work. The Kitchen workers were classified according to the type of work they routinely performed. Forty eight out of the 63 (76.1% cooks who were involved in stirring had callosity at sites of contact with ladle and 28 of the40 (70% cooks who were involved in frying had pigmentation and scars due to contact with hot oil and water. All the onion peelers had staining and fissuring of the palmer aspect of the fingers. Thirty two of the 46(69.5% vegetable cutters had callosity on the palm at areas of contact with knife. Poori markers had pigmentation and callosity of knuckles due to pressing the dough with their knuckles. Nine of the 12 (66% rice cleaners had chapping of nails. Seven of the 12 (58.3% paratha markers had erythema of palm due to contact with hot tava. Tandoori experts had singing of hair over right forearm. Two workers (0.73% had pigmentation of the face probably due to prolonged exposure to heat. Two of the16 (12.5% grinders had paronychia and onychomycosis due to constant contact with water and dough. Nine of the 15 (60% coconut graters had callosities of the palms. We conclude the minor occupational dermatosis is prevalent among kitchen workers employed in hotels

  8. The anterior complex: A visual mnemonic to aid in identification of normal structures.

    Science.gov (United States)

    Ranzini, Angela C

    2017-10-01

    The anterior complex of the fetal brain is a group of structures that are important to evaluate during the routine anatomic survey to exclude several serious brain malformations. These structures include the cavum septum pellucidum, anterior horns, interhemispheric fissure, callosal sulcus, and corpus callosum. The relationship between these structures is easily remembered with the presented visual cartoon. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:477-479, 2017. © 2017 Wiley Periodicals, Inc.

  9. Quantitative analysis of structural variations in corpus callosum in adults with multiple system atrophy (MSA)

    Science.gov (United States)

    Bhattacharya, Debanjali; Sinha, Neelam; Saini, Jitender

    2017-03-01

    Multiple system atrophy (MSA) is a rare, non-curable, progressive neurodegenerative disorder that affects nervous system and movement, poses a considerable diagnostic challenge to medical researchers. Corpus callosum (CC) being the largest white matter structure in brain, enabling inter-hemispheric communication, quantification of callosal atrophy may provide vital information at the earliest possible stages. The main objective is to identify the differences in CC structure for this disease, based on quantitative analysis on the pattern of callosal atrophy. We report results of quantification of structural changes in regional anatomical thickness, area and length of CC between patient-groups with MSA with respect to healthy controls. The method utilizes isolating and parcellating the mid-sagittal CC into 100 segments along the length - measuring the width of each segment. It also measures areas within geometrically defined five callosal compartments of the well-known Witelson, and Hofer-Frahma schemes. For quantification, statistical tests are performed on these different callosal measurements. From the statistical analysis, it is concluded that compared to healthy controls, width is reduced drastically throughout CC for MSA group and as well as changes in area and length are also significant for MSA. The study is further extended to check if any significant difference in thickness is found between the two variations of MSA, Parkinsonian MSA and Cerebellar MSA group, using the same methodology. However area and length of this two sub-MSA group, no substantial difference is obtained. The study is performed on twenty subjects for each control and MSA group, who had T1-weighted MRI.

  10. Inter-hemispheric integration of tactile-motor responses across body parts.

    Science.gov (United States)

    Tamè, Luigi; Longo, Matthew R

    2015-01-01

    In simple detection tasks, reaction times (RTs) are faster when stimuli are presented to the visual field or side of the body ipsilateral to the body part used to respond. This advantage, the crossed-uncrossed difference (CUD), is thought to reflect inter-hemispheric interactions needed for sensorimotor information to be integrated between the two cerebral hemispheres. However, it is unknown whether the tactile CUD is invariant when different body parts are stimulated. The most likely structure mediating such processing is thought to be the corpus callosum (CC). Neurophysiological studies have shown that there are denser callosal connections between regions that represent proximal parts of the body near the body midline and more sparse connections for regions representing distal extremities. Therefore, if the information transfer between the two hemispheres is affected by the density of callosal connections, stimuli presented on more distal regions of the body should produce a greater CUD compared to stimuli presented on more proximal regions. This is because interhemispheric transfer of information from regions with sparse callosal connections will be less efficient, and hence slower. Here, we investigated whether the CUD is modulated as a function of the different body parts stimulated by presenting tactile stimuli unpredictably on body parts at different distances from the body midline (i.e., Middle Finger, Forearm, or Forehead of each side of the body). Participants detected the stimulus and responded as fast as possible using either their left or right foot. Results showed that the magnitude of the CUD was larger on the finger (~2.6 ms) and forearm (~1.8 ms) than on the forehead (≃0.9 ms). This result suggests that the interhemispheric transfer of tactile stimuli varies as a function of the strength of callosal connections of the body parts.

  11. High T2 signal in primary lateral sclerosis supports the topographic distribution of fibers in the corpus callosum: assessing disease in the primary motor segment.

    Science.gov (United States)

    Riad, S M; Hathout, H; Huang, J C

    2011-04-01

    PLS is a disease of the UMN, distinguished from ALS in prognosis and absence of LMN signs. We present, to our knowledge, the first conventional MR imaging visualization of the callosal motor segment, a concept previously supported by primate models, electrophysiologic studies, and postmortem examinations. Modification of the Witelson topographic scheme of the CC is supported by MR tractography. On the basis of 2 cases of PLS, we present conventional imaging confirmation of the revised topographic scheme of fiber distribution across the CC.

  12. Early local differentiation of the cell wall matrix defines the contact sites in lobed mesophyll cells of Zea mays.

    Science.gov (United States)

    Giannoutsou, E; Sotiriou, P; Apostolakos, P; Galatis, B

    2013-10-01

    The morphogenesis of lobed mesophyll cells (MCs) is highly controlled and coupled with intercellular space formation. Cortical microtubule rings define the number and the position of MC isthmi. This work investigated early events of MC morphogenesis, especially the mechanism defining the position of contacts between MCs. The distributions of plasmodesmata, the hemicelluloses callose and (1 → 3,1 → 4)-β-d-glucans (MLGs) and the pectin epitopes recognized by the 2F4, JIM5, JIM7 and LM6 antibodies were studied in the cell walls of Zea mays MCs. Matrix cell wall polysaccharides were immunolocalized in hand-made sections and in sections of material embedded in LR White resin. Callose was also localized using aniline blue in hand-made sections. Plasmodesmata distribution was examined by transmission electron microscopy. Before reorganization of the dispersed cortical microtubules into microtubule rings, particular bands of the longitudinal MC walls, where the MC contacts will form, locally differentiate by selective (1) deposition of callose and the pectin epitopes recognized by the 2F4, LM6, JIM5 and JIM7 antibodies, (2) degradation of MLGs and (3) formation of secondary plasmodesmata clusterings. This cell wall matrix differentiation persists in cell contacts of mature MCs. Simultaneously, the wall bands between those of future cell contacts differentiate with (1) deposition of local cell wall thickenings including cellulose microfibrils, (2) preferential presence of MLGs, (3) absence of callose and (4) transient presence of the pectins identified by the JIM5 and JIM7 antibodies. The wall areas between cell contacts expand determinately to form the cell isthmi and the cell lobes. The morphogenesis of lobed MCs is characterized by the early patterned differentiation of two distinct cell wall subdomains, defining the sites of the future MC contacts and of the future MC isthmi respectively. This patterned cell wall differentiation precedes cortical microtubule

  13. Longitudinal shrinkage of compression wood in dependence on water content and cell wall structure

    Directory of Open Access Journals (Sweden)

    Wiesław Włoch

    2015-01-01

    Full Text Available Compression wood from branches of Pinus silvestris L. was examined. Wide differences were noted in longitudinal shrinkage of the wood when dried from water saturated state. A relation was found between shrinkage and cell wall thickness, particularly of layer S2, and the degree of callose accumulation in the wall. No dependence could be revealed between the shrinkage and the fibril angle in S2.

  14. The destructive citrus pathogen, 'Candidatus Liberibacter asiaticus' encodes a functional flagellin characteristic of a pathogen-associated molecular pattern.

    Directory of Open Access Journals (Sweden)

    Huasong Zou

    Full Text Available Huanglongbing (HLB is presently the most devastating citrus disease worldwide. As an intracellular plant pathogen and insect symbiont, the HLB bacterium, 'Candidatus Liberibacter asiaticus' (Las, retains the entire flagellum-encoding gene cluster in its significantly reduced genome. Las encodes a flagellin and hook-associated protein (Fla of 452 amino acids that contains a conserved 22 amino acid domain (flg22 at positions 29 to 50 in the N-terminus. The phenotypic alteration in motility of a Sinorhizobium meliloti mutant lacking the fla genes was partially restored by constitutive expression of Fla(Las. Agrobacterium-mediated transient expression in planta revealed that Fla(Las induced cell death and callose deposition in Nicotiana benthamiana, and that the transcription of BAK1 and SGT1, which are associated with plant innate immunity, was upregulated. Amino acid substitution experiments revealed that residues 38 (serine and 39 (aspartate of Fla(Las were essential for callose induction. The synthetic flg22(Las peptide could not induce plant cell death but retained the ability to induce callose deposition at a concentration of 20 µM or above. This demonstrated that the pathogen-associated molecular pattern (PAMP activity of flg22 in Las was weaker than those in other well-studied plant pathogenic bacteria. These results indicate that Fla(Las acts as a PAMP and may play an important role in triggering host plant resistance to the HLB bacteria.

  15. β-1,3-Glucans are components of brown seaweed (Phaeophyceae) cell walls.

    Science.gov (United States)

    Raimundo, Sandra Cristina; Pattathil, Sivakumar; Eberhard, Stefan; Hahn, Michael G; Popper, Zoë A

    2017-03-01

    LAMP is a cell wall-directed monoclonal antibody (mAb) that recognizes a β-(1,3)-glucan epitope. It has primarily been used in the immunolocalization of callose in vascular plant cell wall research. It was generated against a brown seaweed storage polysaccharide, laminarin, although it has not often been applied in algal research. We conducted in vitro (glycome profiling of cell wall extracts) and in situ (immunolabeling of sections) studies on the brown seaweeds Fucus vesiculosus (Fucales) and Laminaria digitata (Laminariales). Although glycome profiling did not give a positive signal with the LAMP mAb, this antibody clearly detected the presence of the β-(1,3)-glucan in situ, showing that this epitope is a constituent of these brown algal cell walls. In F. vesiculosus, the β-(1,3)-glucan epitope was present throughout the cell walls in all thallus parts; in L. digitata, the epitope was restricted to the sieve plates of the conductive elements. The sieve plate walls also stained with aniline blue, a fluorochrome used as a probe for callose. Enzymatic digestion with an endo-β-(1,3)-glucanase removed the ability of the LAMP mAb to label the cell walls. Thus, β-(1,3)-glucans are structural polysaccharides of F. vesiculosus cell walls and are integral components of the sieve plates in these brown seaweeds, reminiscent of plant callose.

  16. Corpus callosum anatomy in right-handed homosexual and heterosexual men.

    Science.gov (United States)

    Witelson, Sandra F; Kigar, Debra L; Scamvougeras, Anton; Kideckel, David M; Buck, Brian; Stanchev, Peter L; Bronskill, Michael; Black, Sandra

    2008-12-01

    The results of several studies have shown that homosexual men have an increased prevalence of non-right-handedness and atypical patterns of hemispheric functional asymmetry. Non-right-handedness in men has been associated with increased size of the corpus callosum (CC), particularly of the isthmus, which is the posterior region of the callosal body connecting parietotemporal cortical regions. We hypothesized that isthmal area would be greater in homosexual men, even among right handers. Twelve homosexual and ten heterosexual healthy young men, all consistently right-handed, underwent a research-designed magnetic resonance imaging scan. We found that the isthmal area was larger in the homosexual group, adding to the body of findings of structural brain differences between homosexual and heterosexual men. This result suggests that right-handed homosexual men have less marked functional asymmetry compared to right-handed heterosexual men. The results also indicate that callosal anatomy and laterality for motoric functions are dissociated in homosexual men. A logistic regression analysis to predict sexual orientation category correctly classified 21 of the 22 men (96% correct classification) based on area of the callosal isthmus, a left-hand performance measure, water level test score, and a measure of abstraction ability. Our findings indicate that neuroanatomical structure and cognition are associated with sexual orientation in men and support the hypothesis of a neurobiological basis in the origin of sexual orientation.

  17. Organising white matter in a brain without corpus callosum fibres.

    Science.gov (United States)

    Bénézit, Audrey; Hertz-Pannier, Lucie; Dehaene-Lambertz, Ghislaine; Monzalvo, Karla; Germanaud, David; Duclap, Delphine; Guevara, Pamela; Mangin, Jean-François; Poupon, Cyril; Moutard, Marie-Laure; Dubois, Jessica

    2015-02-01

    Isolated corpus callosum dysgenesis (CCD) is a congenital malformation which occurs during early development of the brain. In this study, we aimed to identify and describe its consequences beyond the lack of callosal fibres, on the morphology, microstructure and asymmetries of the main white matter bundles with diffusion imaging and fibre tractography. Seven children aged between 9 and 13 years old and seven age- and gender-matched control children were studied. First, we focused on bundles within the mesial region of the cerebral hemispheres: the corpus callosum, Probst bundles and cingulum which were selected using a conventional region-based approach. We demonstrated that the Probst bundles have a wider connectivity than the previously described rostrocaudal direction, and a microstructure rather distinct from the cingulum but relatively close to callosal remnant fibres. A sigmoid bundle was found in two partial ageneses. Second, the corticospinal tract, thalamic radiations and association bundles were extracted automatically via an atlas of adult white matter bundles to overcome bias resulting from a priori knowledge of the bundles' anatomical morphology and trajectory. Despite the lack of callosal fibres and the colpocephaly observed in CCD, all major white matter bundles were identified with a relatively normal morphology, and preserved microstructure (i.e. fractional anisotropy, mean diffusivity) and asymmetries. Consequently the bundles' organisation seems well conserved in brains with CCD. These results await further investigations with functional imaging before apprehending the cognition variability in children with isolated dysgenesis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Autopsy findings in EPG5-related Vici syndrome with antenatal onset.

    Science.gov (United States)

    Touraine, Renaud; Laquerrière, Annie; Petcu, Carmen-Adina; Marguet, Florent; Byrne, Susan; Mein, Rachael; Yau, Shu; Mohammed, Shehla; Guibaud, Laurent; Gautel, Mathias; Jungbluth, Heinz

    2017-09-01

    Vici syndrome is one of the most extensive inherited human multisystem disorders and due to recessive mutations in EPG5 encoding a key autophagy regulator with a crucial role in autophagosome-lysosome fusion. The condition presents usually early in life, with features of severe global developmental delay, profound failure to thrive, (acquired) microcephaly, callosal agenesis, cataracts, cardiomyopathy, hypopigmentation, and combined immunodeficiency. Clinical course is variable but usually progressive and associated with high mortality. Here, we present a fetus, offspring of consanguineous parents, in whom callosal agenesis and other developmental brain abnormalities were detected on fetal ultrasound scan (US) and subsequent MRI scan in the second trimester. Postmortem examination performed after medically indicated termination of pregnancy confirmed CNS abnormalities and provided additional evidence for skin hypopigmentation, nascent cataracts, and hypertrophic cardiomyopathy. Genetic testing prompted by a suggestive combination of features revealed a homozygous EPG5 mutation (c.5870-1G>A) predicted to cause aberrant splicing of the EPG5 transcript. Our findings expand the phenotypical spectrum of EPG5-related Vici syndrome and suggest that this severe condition may already present in utero. While callosal agenesis is not an uncommon finding in fetal medicine, additional presence of hypopigmentation, cataracts and cardiomyopathy is rare and should prompt EPG5 testing. © 2017 Wiley Periodicals, Inc.

  19. Sucrose concentration in the growth medium affects the cell wall composition of tobacco pollen tubes.

    Science.gov (United States)

    Biagini, Giovanni; Faleri, Claudia; Cresti, Mauro; Cai, Giampiero

    2014-09-01

    The cell wall of pollen tubes is organized in both spatial and temporal order to allow the pollen tube to grow according to external conditions. The deposition of methyl-esterified and acid pectins in addition to callose/cellulose occurs according to a series of temporally succeeding events. In this work, we attempted to determine how the composition of the external growth medium (in terms of osmolarity) could affect the deposition of cell wall components. Pollen tubes of tobacco were grown in a hypotonic medium and then analyzed for the distribution of pectins and callose/cellulose [as well as for the distribution of the enzyme callose synthase (CALS)]. The data indicate that pollen tubes grown in a hypotonic medium show changes of the initial growth rate followed by modification of the deposition of acid pectins and, to a lesser extent, of CALS. These observations indicate that, under the osmolarity determined by the growth medium, pollen tubes adapt their cell wall to the changing conditions of growth.

  20. The Corpus Callosum and the Visual Cortex: Plasticity Is a Game for Two

    Directory of Open Access Journals (Sweden)

    Marta Pietrasanta

    2012-01-01

    Full Text Available Throughout life, experience shapes and selects the most appropriate brain functional connectivity to adapt to a changing environment. An ideal system to study experience-dependent plasticity is the visual cortex, because visual experience can be easily manipulated. In this paper, we focus on the role of interhemispheric, transcallosal projections in experience-dependent plasticity of the visual cortex. We review data showing that deprivation of sensory experience can modify the morphology of callosal fibres, thus altering the communication between the two hemispheres. More importantly, manipulation of callosal input activity during an early critical period alters developmental maturation of functional properties in visual cortex and modifies its ability to remodel in response to experience. We also discuss recent data in rat visual cortex, demonstrating that the corpus callosum plays a role in binocularity of cortical neurons and is involved in the plastic shift of eye preference that follows a period of monocular eyelid suture (monocular deprivation in early age. Thus, experience can modify the fine connectivity of the corpus callosum, and callosal connections represent a major pathway through which experience can mediate functional maturation and plastic rearrangements in the visual cortex.

  1. Improvement of the soft socket after rotationplasty: a single case study.

    Science.gov (United States)

    Wessling, Martin; Aach, Mirko; Hardes, Jendrik; Janssen, Elmar; Rosenbaum, Dieter; Winkelmann, Winfried; Gebert, Carsten

    2009-03-01

    Rotationplasty is established as a functionally improving and partially ablative method of tumour surgery, but good clinical and functional results do not only depend on a successful surgery. Due to the changed biomechanical situation the activity level is limited by the weight bearing capacity of the rotated foot. Painful blisters and callosities may limit the use of the exo-prosthesis, because the skin is overstressed in the soft socket. A 28-year-old patient with a rotationplasty type A2 suffered from painful callosities of the rotated foot. Capacitive pressure measurements were performed as well as a gait analysis for kinematics and kinetic characteristics. Clinically a decrease of the callosities and a pain relieve was obvious and the patient learned skiing without prior knowledge. Biomechanically a decrease of the peak pressure (from 240.6-135.0 kPa) and the mean pressure (from 83.2-66.2 kPa), was observed with an increased weight bearing area. The study has shown that a modification of the heel bench can considerably improve pressure distribution. An increase of the load bearing area appears to enable the skin to compensate even intensive strain during athletic activities.

  2. Cellulose biosynthesis in higher plants

    Directory of Open Access Journals (Sweden)

    Krystyna Kudlicka

    2014-01-01

    Full Text Available Knowledge of the control and regulation of cellulose synthesis is fundamental to an understanding of plant development since cellulose is the primary structural component of plant cell walls. In vivo, the polymerization step requires a coordinated transport of substrates across membranes and relies on delicate orientations of the membrane-associated synthase complexes. Little is known about the properties of the enzyme complexes, and many questions about the biosynthesis of cell wall components at the cell surface still remain unanswered. Attempts to purify cellulose synthase from higher plants have not been successful because of the liability of enzymes upon isolation and lack of reliable in vitro assays. Membrane preparations from higher plant cells incorporate UDP-glucose into a glucan polymer, but this invariably turns out to be predominantly β -1,3-linked rather than β -1,4-linked glucans. Various hypotheses have been advanced to explain this phenomenon. One idea is that callose and cellulose-synthase systems are the same, but cell disruption activates callose synthesis preferentially. A second concept suggests that a regulatory protein as a part of the cellulose-synthase complex is rapidly degraded upon cell disruption. With new methods of enzyme isolation and analysis of the in vitro product, recent advances have been made in the isolation of an active synthase from the plasma membrane whereby cellulose synthase was separated from callose synthase.

  3. Role of dioxygenase α-DOX2 and SA in basal response and in hexanoic acid-induced resistance of tomato (Solanum lycopersicum) plants against Botrytis cinerea.

    Science.gov (United States)

    Angulo, Carlos; de la O Leyva, María; Finiti, Ivan; López-Cruz, Jaime; Fernández-Crespo, Emma; García-Agustín, Pilar; González-Bosch, Carmen

    2015-03-01

    Resistance of tomato (Solanum Lycopersicum) to the fungal pathogen Botrytis cinerea requires complex interplay between hormonal signalling. In this study, we explored the involvement of new oxylipins in the tomato basal and induced response to this necrotroph through the functional analysis of the tomato α-dioxygenase2 (α-DOX2)-deficient mutant divaricata. We also investigated the role of SA in the defence response against this necrotrophic fungus using SA-deficient tomato nahG plants. The plants lacking dioxigenase α-DOX2, which catalyses oxylipins production from fatty acids, were more susceptible to Botrytis, and hexanoic acid-induced resistance (Hx-IR) was impaired; hence α-DOX2 is required for both tomato defence and the enhanced protection conferred by natural inducer hexanoic acid (Hx) against B. cinerea. The divaricata plants accumulated less pathogen-induced callose and presented lower levels of jasmonic acid (JA) and 12-oxo-phytodienoic acid (OPDA) upon infection if compared to the wild type. Glutathion-S-transferase (GST) gene expression decreased and ROS production significantly increased in Botrytis-infected divaricata plants. These results indicate that absence of α-DOX2 influences the hormonal changes, oxidative burst and callose deposition that occur upon Botrytis infection in tomato. The study of SA-deficient nahG tomato plants showed that the plants with low SA levels displayed increased resistance to Botrytis, but were unable to display Hx-IR. This supports the involvement of SA in Hx-IR. NaghG plants displayed reduced callose and ROS accumulation upon infection and an increased GST expression. This reflects a positive relationship between SA and these defensive mechanisms in tomato. Finally, Hx boosted the pathogen-induced callose in nahG plants, suggesting that this priming mechanism is SA-independent. Our results support the involvement of the oxylipins pathway and SA in tomato response to Botrytis, probably through complex crosstalk of

  4. Agenesis of the corpus callosum and autism: a comprehensive comparison.

    Science.gov (United States)

    Paul, Lynn K; Corsello, Christina; Kennedy, Daniel P; Adolphs, Ralph

    2014-06-01

    The corpus callosum, with its ∼200 million axons, remains enigmatic in its contribution to cognition and behaviour. Agenesis of the corpus callosum is a congenital condition in which the corpus callosum fails to develop; such individuals exhibit localized deficits in non-literal language comprehension, humour, theory of mind and social reasoning. These findings together with parent reports suggest that behavioural and cognitive impairments in subjects with callosal agenesis may overlap with the profile of autism spectrum disorders, particularly with respect to impairments in social interaction and communication. To provide a comprehensive test of this hypothesis, we directly compared a group of 26 adults with callosal agenesis to a group of 28 adults with a diagnosis of autism spectrum disorder but no neurological abnormality. All participants had full-scale intelligence quotient scores >78 and groups were matched on age, handedness, and gender ratio. Using the Autism Diagnostic Observation Schedule together with current clinical presentation to assess autistic symptomatology, we found that 8/26 (about a third) of agenesis subjects presented with autism. However, more formal diagnosis additionally involving recollective parent-report measures regarding childhood behaviour showed that only 3/22 met complete formal criteria for an autism spectrum disorder (parent reports were unavailable for four subjects). We found no relationship between intelligence quotient and autism symptomatology in callosal agenesis, nor evidence that the presence of any residual corpus callosum differentiated those who exhibited current autism spectrum symptoms from those who did not. Relative to the autism spectrum comparison group, parent ratings of childhood behaviour indicated children with agenesis were less likely to meet diagnostic criteria for autism, even for those who met autism spectrum criteria as adults, and even though there was no group difference in parent report of current

  5. Local-global interference is modulated by age, sex and anterior corpus callosum size

    Science.gov (United States)

    Müller-Oehring, Eva M.; Schulte, Tilman; Raassi, Carla; Pfefferbaum, Adolf; Sullivan, Edith V.

    2007-01-01

    To identify attentional and neural mechanisms affecting global and local feature extraction, we devised a global-local hierarchical letter paradigm to test the hypothesis that aging reduces functional cerebral lateralization through corpus callosum (CC) degradation. Participants (37 men and women, 26–79 years) performed a task requiring global, local, or global+local attention and underwent structural MRI for CC measurement. Although reaction time (RT) slowed with age, all participants had faster RTs to local than global targets. This local precedence effect together with greater interference from incongruent local information and greater response conflict from local targets each correlated with older age and smaller callosal genu (anterior) areas. These findings support the hypothesis that the CC mediates lateralized local-global processes by inhibition of task-irrelevant information under selective attention conditions. Further, with advancing age smaller genu size leads to less robust inhibition, thereby reducing cerebral lateralization and permitting interference to influence processing. Sex was an additional modifier of interference, in that callosum-interference relationships were evident in women but not in men. Regardless of age, smaller splenium (posterior) areas correlated with less response facilitation from repetition priming of global targets in men, but with greater response facilitation from repetition priming of local targets in women. Our data indicate the following dissociation: Anterior callosal structure was associated with inhibitory processes (i.e., interference from incongruency and response conflict), which are vulnerable to the effects of age and sex, whereas posterior callosal structure was associated with facilitation processes from repetition priming dependent on sex and independent of age. PMID:17335783

  6. Quarter and cow risk factors associated with the occurrence of clinical mastitis in dairy cows in the United Kingdom.

    Science.gov (United States)

    Breen, J E; Green, M J; Bradley, A J

    2009-06-01

    Quarter and cow risk factors associated with the development of clinical mastitis (CM) during lactation were investigated during a 12-mo longitudinal study on 8 commercial Holstein-Friesian dairy farms in the southwest of England. The individual risk factors studied on 1,677 cows included assessments of udder and leg hygiene, teat-end callosity, and hyperkeratosis; body condition score; and measurements of monthly milk quality and yield. Several outcome variables for CM were used for statistical analysis, which included use of generalized linear mixed models. Significant covariates associated with an increased risk of CM were increasing parity, decreasing month of lactation, cows with very dirty udders, and quarters with only very severe hyperkeratosis of the teat-end. Thin and moderate smooth teat-end callosity scores were not associated with an increased risk for CM. Cows that recorded a somatic cell count >199,000 cells/mL and a milk protein percentage cow body condition score and incidence of CM. Of the cases of CM available for culture, 171 (26.7%) were confirmed as being caused by Escherichia coli and 121 (18.9%) confirmed as being caused by Streptococcus uberis. Quarters with moderate and very severe hyperkeratosis of the teat-end were at significantly increased risk of clinical E. coli mastitis before the next visit. Quarters with very severe hyperkeratosis of the teat-end were significantly more likely to develop clinical Strep. uberis mastitis before the next visit. There were strong trends within the data to suggest an association between very dirty udders (an increased risk of clinical E. coli mastitis) and teat-ends with no callosity ring present (an increased risk of clinical Strep. uberis mastitis). These results highlight the importance of individual quarter- and cow-level risk factors in determining the risk of CM associated with environmental pathogens during lactation.

  7. Effects of exogenous plant growth regulator abscisic acid-induced resistance in rice on the expression of vitellogenin mRNA in Nilaparvata lugens (Hemiptera: Delphacidae) adult females.

    Science.gov (United States)

    Liu, Jing-Lan; Chen, Xiao; Zhang, Hong-Mei; Yang, Xia; Wong, Andrew

    2014-01-01

    Recent study showed that exogenous abscisic acid (ABA) acts as a regulator of plant resistance. This study investigated average injury scale and callose contents of rice, and vitellogenin (Nlvg) mRNA expression in Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) adult females after third instar nymphs fed on exogenous ABA-treated susceptible [Taichung Native one (TN1)] and moderately resistant (IR42) rice cultivars. The results showed that exogenous ABA significantly decreased average injury scale of rice and Nlvg mRNA expression in N. lugens adults compared with the control (without ABA spraying). Nlvg mRNA expression in N. lugens adults decreased significantly after third instar nymphs fed on ABA-treated (5, 20, and 40 mg/liter) TN1 for 1 and 2 d, and for IR42, after fed on ABA-treated (20 and 40 mg/liter) rice plants for 1 d and after fed on ABA-treated (5, 20, and 40 mg/liter) rice for 2 d decreased significantly. The callose contents showed no significant change for TN1, while for IR42, significantly increased in roots and sheathes after N. lugens infestation under ABA treatments (20 and 40 mg/liter) compared with the control. The decrease of Nlvg mRNA expression may be partially attributed to the increase of callose content of plants. The results provide a profile for concerning the effects of ABA-induced rice plants' defenses on phloem-feeding insects. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  8. The role of corpus callosum development in functional connectivity and cognitive processing.

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    Leighton B N Hinkley

    Full Text Available The corpus callosum is hypothesized to play a fundamental role in integrating information and mediating complex behaviors. Here, we demonstrate that lack of normal callosal development can lead to deficits in functional connectivity that are related to impairments in specific cognitive domains. We examined resting-state functional connectivity in individuals with agenesis of the corpus callosum (AgCC and matched controls using magnetoencephalographic imaging (MEG-I of coherence in the alpha (8-12 Hz, beta (12-30 Hz and gamma (30-55 Hz bands. Global connectivity (GC was defined as synchronization between a region and the rest of the brain. In AgCC individuals, alpha band GC was significantly reduced in the dorsolateral pre-frontal (DLPFC, posterior parietal (PPC and parieto-occipital cortices (PO. No significant differences in GC were seen in either the beta or gamma bands. We also explored the hypothesis that, in AgCC, this regional reduction in functional connectivity is explained primarily by a specific reduction in interhemispheric connectivity. However, our data suggest that reduced connectivity in these regions is driven by faulty coupling in both inter- and intrahemispheric connectivity. We also assessed whether the degree of connectivity correlated with behavioral performance, focusing on cognitive measures known to be impaired in AgCC individuals. Neuropsychological measures of verbal processing speed were significantly correlated with resting-state functional connectivity of the left medial and superior temporal lobe in AgCC participants. Connectivity of DLPFC correlated strongly with performance on the Tower of London in the AgCC cohort. These findings indicate that the abnormal callosal development produces salient but selective (alpha band only resting-state functional connectivity disruptions that correlate with cognitive impairment. Understanding the relationship between impoverished functional connectivity and cognition is a key

  9. An automated strategy for the delineation and parcellation of commissural pathways suitable for clinical populations utilising high angular resolution diffusion imaging tractography.

    Science.gov (United States)

    Pannek, Kerstin; Mathias, Jane L; Bigler, Erin D; Brown, Greg; Taylor, Jamie D; Rose, Stephen

    2010-04-15

    There is a growing interest in understanding alterations to the interhemispheric transfer of information as a result of brain injury and neurological disease. To facilitate research, we have developed a fully automated method for the accurate extraction of commissural pathways (corpus callosum (CC) and anterior commissure (AC)) and functional parcellation of the CC using a high angular resolution diffusion imaging (HARDI) based probabilistic tractography approach that is applicable to clinical populations. The CC was divided into 33 functional divisions based on its connections to cortical parcellations derived from individual structural images in 8 healthy participants. Probabilistic CC population maps acquired at two different b-values (1000 s mm(-2) and 3000 s mm(-2)) are presented. Topography of the CC was consistent with histology reports. We show that HARDI data acquired at a higher b-value reveals more callosal-temporal connections than low b-value data. With respect to intra-subject precision, data acquired using a higher b-value show superior reproducibility of the delineated CC area on the midsagittal plane (MSP), as well as the total number of callosal streamlines and the number of clustered callosal streamlines. The AC was delineated in all 8 participants using high b-value HARDI tractography. Cortical projections of the AC were analysed and are in agreement with known anatomy. We conclude that, while data acquired at a lower b-value may be used, this is associated with a loss in quality, both in the delineation of commissural pathways and, potentially, the reproducibility of results over time. Copyright 2010 Elsevier Inc. All rights reserved.

  10. Association of Metatarsalgia After Hallux Valgus Correction With Relative First Metatarsal Length.

    Science.gov (United States)

    Nakagawa, Satoru; Fukushi, Jun-Ichi; Nakagawa, Takeshi; Mizu-Uchi, Hideki; Iwamoto, Yukihide

    2016-06-01

    Metatarsalgia is frequently associated with hallux valgus. The aim of this study was to evaluate how the relative length and position of the first metatarsal head influenced metatarsalgia and plantar callosities beneath the lesser metatarsal heads. A retrospective analysis of the clinical data and radiographs of 102 cases was performed at a mean follow-up of 16 months after biplane interlocking osteotomies. Clinical evaluation was made using the Japanese Society for Surgery of the Foot (JSSF) hallux scale. Radiologic evaluation was made with standard weight-bearing anteroposterior radiographs, and the hallux valgus angle (HVA), intermetatarsal 1-2 angle (IMA), distal metatarsal articular angulation (DMAA), and the sesamoid position were evaluated. Relative first metatarsal length (RML) was determined according to Nilsonne/Morton's technique. The mean preoperative HVA decreased from 37 to 3 degrees, and the mean IMA from 17 to 4 degrees. The mean JSSF-hallux score improved from 56 to 96 points. The mean preoperative area of plantar callosities decreased from 3.1 to 1.5 mm(2). Sixty percent of metatarsalgia cases improved, and 85% of painless callosities disappeared postoperatively. Among radiologic parameters, postoperative RML was most significantly associated with JSSF score (P < .0001) and the presence of postoperative metatarsalgia (P < .0001). Receiver operating characteristic analysis revealed that the RML cut-off point was -3 mm for avoiding metatarsalgia, with an area under the curve of 0.88, a specificity of 88%, and a sensitivity of 85%. Preservation of relative first metatarsal length during first metatarsal osteotomy was important to prevent postoperative metatarsalgia. Level IV, retrospective case series. © The Author(s) 2016.

  11. The impact of healthy parenting as a protective factor for posttraumatic stress disorder in adulthood: a case-control study.

    Directory of Open Access Journals (Sweden)

    Adriano R Lima

    Full Text Available BACKGROUND: Early life social adversity can influence stress response mechanisms and is associated with anxious behaviour and reductions in callosal area later in life. OBJECTIVE: To evaluate the association between perceptions of parental bonding in childhood/adolescence, hypothalamic-pituitary-adrenal (HPA axis response, and callosal structural integrity in adult victims of severe urban violence with and without PTSD. METHODS: Seventy-one individuals with PTSD and 62 without the disorder were assessed with the Parental Bonding Instrument (PBI. The prednisolone suppression test was administered to assess cortisol levels, and magnetic resonance imaging was used to assess the total area of the corpus callosum (CC, as well as the areas of callosal subregions. RESULTS: The PBI items related to the perception of 'not having a controlling mother' (OR 4.84; 95%CI [2.26-10.3]; p=0.01, 'having a caring father' (OR 2.46; 95'%CI [1.18-5.12]; p=0.02, and 'not having controlling parents' (OR 2.70; 95%CI [1.10-6.63]; p=0.04 were associated with a lower risk of PTSD. The PTSD group showed a blunted response to the prednisolone suppression test, with lower salivary cortisol levels upon waking up (p=0.03. Individuals with PTSD had smaller total CC area than those without the disorder, but these differences were not statistically significant (e-value =0.34. CONCLUSIONS: Healthy parental bonding, characterized by the perception of low parental control and high affection, were associated with a lower risk of PTSD in adulthood, suggesting that emotional enrichment and the encouragement of autonomy are protective against PTSD in adulthood.

  12. Foot and ankle problems in Muay Thai kickboxers.

    Science.gov (United States)

    Vaseenon, Tanawat; Intharasompan, Piyapong; Wattanarojanapom, Thongaek; Theeraamphon, Nipon; Auephanviriyakul, Sansanee; Phisitkul, Phinit

    2015-01-01

    Muay Thai kickboxing is a common sport that uses the foot and ankle in fighting. Muay Thai kickboxing trainees usually receive training in Thailand Foot and ankle problems in this group ofpeople who usually train barefoot remain unexplored To evaluate the prevalence of common foot and ankle problems in Muay Thai kick boxers. The present study is a cross-sectional survey of Muay Thai kick boxers practicing in northern Thailand. Interviews were conducted and foot and ankle examinations were evaluated Foot morphology was examined using a Harris mat footprint. One hundred and twenty-three Muay Thai kickbox ersinnine training gyms were included in this study. Common foot and ankle problems found in the Muay Thai kick boxers were callosity (59%), gastrocnemius contracture (57%), toe deformities (49.3%), wounds (10%) and heel pain (9%). Callosity was most commonly found on the forefoot (77.5%), on the plantar first metatarsal (55.3%) and on the big toe (33.3%). An association was found between a tight heel cord and a history of foot injury with prolonged periods of weekly training. Toe deformities such as hallux rigidus (37.6%) were also associated with prolonged periods of training (p = 0.001). No correlation was found between type of foot arch and foot and ankle problems. Plantar forefoot callosities and wounds as well as toe deformities including tight heel cords are some of the foot and ankle problems commonly found in Muay Thai kick boxers. They are associated with prolonged periods of barefoot training. The unique pattern of training and of the kicks in Muay Thai might be a path mechanism, leading to the development of foot and ankle problems.

  13. Interhemispheric versus stimulus-response spatial compatibility effects in bimanual reaction times to lateralized visual stimuli

    Directory of Open Access Journals (Sweden)

    Antonello ePellicano

    2013-06-01

    Full Text Available In the present study, we tested right- and left-handed participants in a Poffenberger paradigm with bimanual responses and hands either in an anatomical or in a left-right inverted posture. We observed a significant positive crossed-uncrossed difference (CUD in reaction times for both manual dominance groups and both response postures. These results rule out an explanation of the CUD in terms of stimulus-response spatial compatibility and provide convincing evidence on the important role of interhemispheric callosal transfer in bimanual responding in right- as well as left-handed individuals.

  14. Reference: 500 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available Daniël et al. 2006 Dec. Plant Cell 18(12):3502-18. TPLATE was previously identified as a potential cytokines...of shriveled pollen unable to germinate. Vesicular compartmentalization of the mature... pollen is dramatically altered, and large callose deposits accumulate near the intine cell wall layer. Green fluore...scent protein (GFP)-tagged TPLATE expression under the control of the pollen promoter Lat52 comp...lements the phenotype. Downregulation of TPLATE in Arabidopsis seedlings and toba

  15. Ipsilateral Hemichorea-hemiballism in a Case of Postoperative Stroke

    Directory of Open Access Journals (Sweden)

    Narasinga Rao V. Kannepalli

    2016-04-01

    Full Text Available Background: Ipsilateral hemiballismus refers to the rare occurrence of hemiballism developing on the same side of a brain lesion.Case report: We describe a rare case of postoperative ipsilateral hemiballism in a patient who underwent pituitary adenoma resection and experienced a right internal cerebral artery territory infarct. We review the literature on hemichorea hemiballismus (HCHB and explore various mechanisms for its occurrence.Discussion: Only three cases of ipsilateral hemiballism have been described, and the exact pathophysiology remains unknown. A dominant left hemisphere with corpus callosal connections to the right basal ganglia is the most probable explanation for this unusual event. 

  16. [Unilateral aplasia of the cerebellum in Aicardi's syndrome].

    Science.gov (United States)

    Serrano González, C; Prats Viñas, J M

    1998-05-01

    A case of unilateral aplasia of the cerebellum in a girl with Aicardi's syndrome is described. Aplasia of an entire hemisphere is one of the least frequent malformations of the cerebellum. Hypoplasia, partial hemispheric defects of the cerebellum and, rarely, complete absence of one hemisphere have been described in Aicardi's syndrome, which is associated with multiple systemic and CNS malformations. In our patient, who presented the characteristic trial of infantile spasms, callosal agenesia and retinal lacuna, we also saw right cerebellar aplasia along with other CNS malformations using magnetic resonance. We discuss the possibility that this aplasia arises as the result of a developmental defect of the posterior arterial system of Willis's polygon.

  17. [Influence of salicylic and succinic acids on the cytophysiological reactions of wheat infected by brown rust].

    Science.gov (United States)

    Plotnikova, L Ia; Shtubeĭ, T Iu

    2009-01-01

    The influence of the salicylic and succinic acids on the cytophysiological reactions of the plants and cellular structures of the fungus were investigated using the model of common wheat Triticum aestivum L. infected by brown rust. The experiments were performed on seedlings of the isogenic line of var. Thatcher with resistant gene Lr19. The salicylic and succinic acids accelerated and enhanced to a different extent the generation of active oxygen species and synthesis of callose and phenylpropanoids by the plant cells contacting with cellular structures of avirulent and virulent fungal clones.

  18. Acquired lesions of the corpus callosum: MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Takase, Y.; Nomiyama, K.; Egashira, R.; Kudo, S. [Saga Medical School, Department of Radiology, Saga (Japan)

    2006-04-15

    In this pictorial review, we illustrate acquired diseases or conditions of the corpus callosum that may be found by magnetic resonance (MR) imaging of the brain, including infarction, bleeding, diffuse axonal injury, multiple sclerosis, acute disseminated encephalomyelitis, Marchiafava-Bignami disease, glioblastoma, gliomatosis cerebri, lymphoma, metastasis, germinoma, infections, metabolic diseases, transient splenial lesion, dilated Virchow-Robin spaces, wallerian degeneration after hemispheric damage and focal splenial gliosis. MR imaging is useful for the detection and differential diagnosis of corpus callosal lesions. Due to the anatomical shape and location of the corpus callosum, both coronal and sagittal fluid-attenuated inversion recovery images are most useful for visualizing lesions of this structure. (orig.)

  19. Megalencephaly, mega corpus callosum, and complete lack of motor development: delineation of a rare syndrome.

    Science.gov (United States)

    Hengst, Meike; Tücke, Jens; Zerres, Klaus; Blaum, Marcus; Häusler, Martin

    2010-09-01

    Unlike atrophy of the corpus callosum (CC), callosal hypertrophy is a rare neuroimaging finding with only few reported patients. The "megalencephaly, mega CC, and complete lack of motor development" syndrome is morphologically characterized by generalized megalencephaly, a thickened CC, and extensive polymicrogyria causing a pachygyric appearance. We report on the fifth patient showing this rare syndrome, a 3-year-old girl displaying the typical neuroimaging features. Clinically she showed a severely impaired motor, mental, and speech development with marked muscular hypotonia but no dysmorphic facial signs. She also retained the ability to move by rolling sidewards so that complete lack of motor development may not be a consistent feature.

  20. Monozygotic twins with a new compound heterozygous SPG11 mutation and different disease expression.

    Science.gov (United States)

    Schneider-Gold, Christiane; Dekomien, Gabriele; Regensburger, Martin; Schneider, Ruth; Trampe, Nadine; Krogias, Christos; Lukas, Carsten; Bellenberg, Barbara

    2017-10-15

    A pair of monozygotic 22-year-old twins with complicated hereditary spastic paraplegia caused by a novel SPG11 mutation is described. Genetic testing and thorough clinical examination, magnetic resonance imaging (MRI) and MR-spectroscopy were performed. The twins were compound heterozygous for a known frameshift as well as a novel splice site mutation in the SPG11 gene. Clinically the patients showed a similar spectrum of symptoms but different disease presentation. MRI studies including morphometry and regional microstructural analysis by diffusion tensor imaging (DTI) of the corpus callosum (CC) by 3T MRI revealed marked thinning and corresponding increases of radial diffusivity (RD) and apparent diffusion coefficient (ADC) and reduction of the fractional anisotropy (FA) as compared to controls in all CC sections, particularly in the anterior callosal body. There was marked mainly supratentorial white matter reduction and to a lesser extent grey matter reduction in both patients. Involvement of the cortico-spinal tracts was reflected by FA and RD alterations. The more strongly affected patient showed a higher degree of callosal microstructural damage and cervical cord atrophy. This study shows a similar symptom spectrum, but distinct clinical and imaging findings in monozygotic twins suffering from SPG 11, suggesting individual downstream genetic effects and/or non-genetic modifiers. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Anatomic and Molecular Development of Corticostriatal Projection Neurons in Mice

    Science.gov (United States)

    Sohur, U. Shivraj; Padmanabhan, Hari K.; Kotchetkov, Ivan S.; Menezes, Joao R.L.; Macklis, Jeffrey D.

    2014-01-01

    Corticostriatal projection neurons (CStrPN) project from the neocortex to ipsilateral and contralateral striata to control and coordinate motor programs and movement. They are clinically important as the predominant cortical population that degenerates in Huntington's disease and corticobasal ganglionic degeneration, and their injury contributes to multiple forms of cerebral palsy. Together with their well-studied functions in motor control, these clinical connections make them a functionally, behaviorally, and clinically important population of neocortical neurons. Little is known about their development. “Intratelencephalic” CStrPN (CStrPNi), projecting to the contralateral striatum, with their axons fully within the telencephalon (intratelencephalic), are a major population of CStrPN. CStrPNi are of particular interest developmentally because they share hodological and axon guidance characteristics of both callosal projection neurons (CPN) and corticofugal projection neurons (CFuPN); CStrPNi send axons contralaterally before descending into the contralateral striatum. The relationship of CStrPNi development to that of broader CPN and CFuPN populations remains unclear; evidence suggests that CStrPNi might be evolutionary “hybrids” between CFuPN and deep layer CPN—in a sense “chimeric” with both callosal and corticofugal features. Here, we investigated the development of CStrPNi in mice—their birth, maturation, projections, and expression of molecular developmental controls over projection neuron subtype identity. PMID:23118198

  2. Selenite-induced nitro-oxidative stress processes in Arabidopsis thaliana and Brassica juncea.

    Science.gov (United States)

    Molnár, Árpád; Kolbert, Zsuzsanna; Kéri, Krisztina; Feigl, Gábor; Ördög, Attila; Szőllősi, Réka; Erdei, László

    2018-02-01

    Extremes of selenium (Se) exert toxic effects on plants' physiological processes; although plant species tolerate Se differently. This study focuses on the effect of Se (0, 20, 50 or 100μM sodium selenite) on secondary nitro-oxidative stress processes mainly using in situ microscopic methods in non-accumulator Arabidopsis thaliana and secondary Se accumulator Brassica juncea. Relative Se tolerance or sensitivity of the species was evaluated based on growth parameters (fresh and dry weight, root growth) and cell viability. Besides, selenite-triggered cell wall modifications (pectin, callose) and stomatal regulations were determined for the first time. In case of Arabidopsis, relative selenite sensitivity was accompanied by decreased stomatal density and induced stomatal opening, callose accumulation, pronounced oxidative stress and moderate nitrosative modifications. In contrast, the selenite-treated, relatively tolerant Brassica juncea showed larger number of more opened stomata, pectin accumulation, moderate oxidative and intense nitrosative stress. These suggest that selenite tolerance or sensitivity is rather associated with oxidative processes than secondary nitrosative modifications in higher plants. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Aluminium localization and toxicity symptoms related to root growth inhibition in rice (Oryza sativa L.) seedlings.

    Science.gov (United States)

    Alvim, M N; Ramos, F T; Oliveira, D C; Isaias, R M S; Franca, M G C

    2012-12-01

    We correlated root growth inhibition with aluminium (Al(3+)) localization and toxicity symptoms in rice roots using seedlings of two genotypes (tolerant and sensitive) that were exposed to different AlCl(3) concentrations. Al(3+) localization was evaluated by hematoxylin in primary roots and by morin in cross-sections of the root tips. Neutral invertase enzyme activity and callose (1 -- 3, beta-D-glucan) accumulation were observed and compared with Al(3+) accumulation sites. Root growth was inhibited by Al(3+) in a concentration-specific manner and proportional to the increase of hematoxylin staining, being more pronounced in the sensitive genotype. Morin staining showed the presence of Al(3+) deep within the roots of the sensitive genotype, indicating that the metal was able to penetrate beyond the first few cell layers. In the tolerant genotype, Al(3+) penetration was restricted to the first two cell layers. Ruptures in exodermis and epidermis layers by lateral root protrusions in both genotypes allowed Al3+ to enter into the roots. More intense activity of invertase in roots of the tolerant genotype was also observed, which could be related to greater root growth of this cultivar when submitted to Al(3+) stress. Moreover, Al(3+)-induced callose accumulation was a late response occurring in the same areas where Al(3+) was present.

  4. Phloem-Conducting Cells in Haustoria of the Root-Parasitic Plant Phelipanche aegyptiaca Retain Nuclei and Are Not Mature Sieve Elements

    Directory of Open Access Journals (Sweden)

    Minako Ekawa

    2017-12-01

    Full Text Available Phelipanche aegyptiaca parasitizes a wide range of plants, including important crops, and causes serious damage to their production. P. aegyptiaca develops a specialized intrusive organ called a haustorium that establishes connections to the host’s xylem and phloem. In parallel with the development of xylem vessels, the differentiation of phloem-conducting cells has been demonstrated by the translocation of symplasmic tracers from the host to the parasite. However, it is unclear yet whether haustorial phloem-conducting cells are sieve elements. In this study, we identified phloem-conducting cells in haustoria by the host-to-parasite translocation of green fluorescent protein (GFP from AtSUC2pro::GFP tomato sieve tubes. Haustorial GFP-conducting cells contained nuclei but not callose-rich sieve plates, indicating that phloem-conducting cells in haustoria differ from conventional sieve elements. To ascertain why the nuclei were not degenerated, expression of the P. aegyptiaca homologs NAC-domain containing transcription factor (NAC45, NAC45/86-dependent exonuclease-domain protein 1 (NEN1, and NEN4 was examined. However, these genes were more highly expressed in the haustorium than in tubercle protrusion, implying that nuclear degradation in haustoria may not be exclusively controlled by the NAC45/86-NEN regulatory pathway. Our results also suggest that the formation of plasmodesmata with large size exclusion limits is independent of nuclear degradation and callose deposition.

  5. White Matter Volume Abnormalities and Associations with Symptomatology in Schizophrenia

    Science.gov (United States)

    Makris, N.; Seidman, L. J.; Ahern, T.; Kennedy, D. N.; Caviness, V. S.; Tsuang, M. T.; Goldstein, J. M.

    2010-01-01

    The cerebral white matter (WM) is critically involved in many bio-behavioral functions impaired in schizophrenia. However, the specific neural systems underlying symptomatology in schizophrenia are not well known. By comparing the volume of all brain fiber systems between chronic patients with DSM-III-R schizophrenia (n = 88) and matched healthy community controls (n = 40), we found that a set of a priori WM regions of local and distal associative fiber systems were significantly different in patients with schizophrenia. There were significant positive correlations between volumes (larger) in anterior callosal, cingulate and temporal deep WM regions (related to distal connections) with positive symptoms, such as hallucinations, delusions and bizarre behavior, and significant negative correlation between volumes (smaller) in occipital and paralimbic superficial WM (related to local connections) and posterior callosal fiber systems with higher negative symptoms, such as alogia. Furthermore, the temporal sagittal system showed significant rightward asymmetry between patients and controls. These observations suggest a pattern of volume WM alterations associated with symptomatology in schizophrenia that may be related in part to predisposition to schizophrenia. PMID:20538438

  6. The cell wall-localized atypical β-1,3 glucanase ZERZAUST controls tissue morphogenesis in Arabidopsis thaliana.

    Science.gov (United States)

    Vaddepalli, Prasad; Fulton, Lynette; Wieland, Jennifer; Wassmer, Katrin; Schaeffer, Milena; Ranf, Stefanie; Schneitz, Kay

    2017-06-15

    Orchestration of cellular behavior in plant organogenesis requires integration of intercellular communication and cell wall dynamics. The underlying signaling mechanisms are poorly understood. Tissue morphogenesis in Arabidopsis depends on the receptor-like kinase STRUBBELIG. Mutations in ZERZAUST were previously shown to result in a strubbelig-like mutant phenotype. Here, we report on the molecular identification and functional characterization of ZERZAUST We show that ZERZAUST encodes a putative GPI-anchored β-1,3 glucanase suggested to degrade the cell wall polymer callose. However, a combination of in vitro, cell biological and genetic experiments indicate that ZERZAUST is not involved in the regulation of callose accumulation. Nonetheless, Fourier-transformed infrared-spectroscopy revealed that zerzaust mutants show defects in cell wall composition. Furthermore, the results indicate that ZERZAUST represents a mobile apoplastic protein, and that its carbohydrate-binding module family 43 domain is required for proper subcellular localization and function whereas its GPI anchor is dispensable. Our collective data reveal that the atypical β-1,3 glucanase ZERZAUST acts in a non-cell-autonomous manner and is required for cell wall organization during tissue morphogenesis. © 2017. Published by The Company of Biologists Ltd.

  7. Colletotrichum orbiculare WHI2, a Yeast Stress-Response Regulator Homolog, Controls the Biotrophic Stage of Hemibiotrophic Infection Through TOR Signaling.

    Science.gov (United States)

    Harata, Ken; Nishiuchi, Takumi; Kubo, Yasuyuki

    2016-06-01

    The hemibiotrophic fungus Colletotrichum orbiculare first establishes a biotrophic infection stage in cucumber (Cucumber sativus) epidermal cells and subsequently transitions to a necrotrophic stage. Here, we found that C. orbiculare established hemibiotrophic infection via C. orbiculare WHI2, a yeast stress regulator homolog, and TOR (target of rapamycin) signaling. Plant defense responses such as callose deposition, H2O2, and antimicrobial proteins were strongly induced by the C. orbiculare whi2Δ mutant, resulting in defective pathogenesis. Expression analysis of biotrophy-specific genes evaluated by the promoter VENUS fusion gene indicated weaker VENUS signal intensity in the whi2Δ mutant, thereby suggesting that C. orbiculare WHI2 plays a key role in regulating biotrophic infection of C. orbiculare. The involvement of CoWHI2 in biotrophic infection was further explored with a DNA microarray. In the Cowhi2Δ mutant, TOR-dependent ribosomal protein-related genes were strikingly upregulated compared with the wild type. Moreover, callose deposition in the host plant after inoculation with the Cowhi2Δ mutant treated with rapamycin, which inhibits TOR activity, was reduced, and the mutant remained biotrophic in contrast to the untreated mutant. Thus, regulation of TOR by Whi2 is apparently crucial to the biotrophic stage of hemibiotrophic infection in C. orbiculare.

  8. Corpus callosum atrophy in Wernicke's encephalopathy.

    Science.gov (United States)

    Lee, Soon-Tae; Jung, Young-Min; Na, Duk L; Park, Seong Ho; Kim, Manho

    2005-10-01

    Neuropathologic changes in Wernicke's encephalopathy (WE) involve variable brain structures. Corpus callosum involvement in WE, however, is largely unknown. The authors investigated the degree and the pattern of corpus callosum changes in WE according to the etiologies. Nineteen patients with WE (between 34 and 81 years) and 19 age- and sex-matched control participants were included. The total cross-sectional callosal area and 5 callosal subregions (C1-C5) were measured by tracing outer margins in the midsagittal sections. Subregions were determined by placing radial dividers with 10 rays. The pixel numbers for corpus callosums were calculated, and the values obtained were adjusted for head size variations. The causes of WE were alcoholism (10), intestinal surgery (5), anorexia (3), and hyperemesis gravidarum (1). The mean size of the total corpus callosum was significantly reduced in alcoholic WE (P< .001; 527.8 +/- 70.8 mm2 for alcoholic WE; 664.6 +/- 58.1 mm2 for the corresponding controls), but not in nonalcoholic WE. In subregion analysis, prefrontal callosum (C2) atrophy was the most prominent in alcoholic WE. In contrast, only splenium (C5) was atrophied in nonalcoholic WE. The degree of atrophy did not change throughout the follow-up period (mean 5.3 weeks). This study suggests that the extent and location of corpus callosum atrophy differs between alcoholic WE and nonalcoholic WE, implying separate contribution of alcohol neurotoxicity and nutritional deficiency.

  9. Does the use of high-heeled shoes lead to fore-foot pathology? A controlled cohort study comprising 197 women.

    Science.gov (United States)

    Borchgrevink, Grethe E; Viset, Annja T; Witsø, Eivind; Schei, Berit; Foss, Olav A

    2016-12-01

    High-heeled shoes have been suggested as a main explanation for the female dominance in foot pain and deformities. Aim of study was to test this hypothesis scientifically. Women 40-66 years were included in two groups. 95 women who had worn high-heeled shoes at work for at least 5 years were compared to 102 women who had never worn high-heeled shoes at work. The investigations were weight bearing radiographs of foot and ankle, the SEFAS questionnaire and the AOFAS Clinical Rating System. Evaluators were blinded to the group-affiliation. Radiographs showed no statistically significant differences between the two groups concerning deformities or joint disease. Foot function measured by SEFAS and AOFAS total score, were similar in the two groups. The high-heeled group had more pain and more callosities. For women aged 40-66 years wearing of high-heeled shoes had not caused foot deformation, but more foot pain and callosities. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. The NIa-Pro protein of Turnip mosaic virus improves growth and reproduction of the aphid vector, Myzus persicae (green peach aphid).

    Science.gov (United States)

    Casteel, Clare L; Yang, Chunling; Nanduri, Ananya C; De Jong, Hannah N; Whitham, Steven A; Jander, Georg

    2014-02-01

    Many plant viruses depend on aphids and other phloem-feeding insects for transmission within and among host plants. Thus, viruses may promote their own transmission by manipulating plant physiology to attract aphids and increase aphid reproduction. Consistent with this hypothesis, Myzus persicae (green peach aphids) prefer to settle on Nicotiana benthamiana infected with Turnip mosaic virus (TuMV) and fecundity on virus-infected N. benthamiana and Arabidopsis thaliana (Arabidopsis) is higher than on uninfected controls. TuMV infection suppresses callose deposition, an important plant defense, and increases the amount of free amino acids, the major source of nitrogen for aphids. To investigate the underlying molecular mechanisms of this phenomenon, 10 TuMV genes were over-expressed in plants to determine their effects on aphid reproduction. Production of a single TuMV protein, nuclear inclusion a-protease domain (NIa-Pro), increased M. persicae reproduction on both N. benthamiana and Arabidopsis. Similar to the effects that are observed during TuMV infection, NIa-Pro expression alone increased aphid arrestment, suppressed callose deposition and increased the abundance of free amino acids. Together, these results suggest a function for the TuMV NIa-Pro protein in manipulating the physiology of host plants. By attracting aphid vectors and promoting their reproduction, TuMV may influence plant-aphid interactions to promote its own transmission. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  11. Induction of Systemic Resistance against Aphids by Endophytic Bacillus velezensis YC7010 via Expressing PHYTOALEXIN DEFICIENT4 in Arabidopsis

    Science.gov (United States)

    Rashid, Md. Harun-Or-; Khan, Ajmal; Hossain, Mohammad T.; Chung, Young R.

    2017-01-01

    Aphids are the most destructive insect pests. They suck the sap and transmit plant viruses, causing widespread yield loss of many crops. A multifunctional endophytic bacterial strain Bacillus velezensis YC7010 has been found to induce systemic resistance against bacterial and fungal pathogens of rice. However, its activity against insects attack and underlying cellular and molecular defense mechanisms are not elucidated yet. Here, we show that root drenching of Arabidopsis seedlings with B. velezensis YC7010 can induce systemic resistance against green peach aphid (GPA), Myzus persicae. Treatment of bacterial suspension of B. velezensis YC7010 at 2 × 107 CFU/ml to Arabidopsis rhizosphere induced higher accumulation of hydrogen peroxide, cell death, and callose deposition in leaves compared to untreated plants at 6 days after infestation of GPA. Salicylic acid, jasmonic acid, ethylene, and abscisic acid were not required to confer defense against GPA in Arabidopsis plants treated by B. velezensis YC7010. Bacterial treatment with B. velezensis YC7010 significantly reduced settling, feeding and reproduction of GPA on Arabidopsis leaves via strongly expressing senescence-promoting gene PHYTOALEXIN DEFICIENT4 (PAD4) while suppressing BOTRYTIS-INDUCED KINASE1 (BIK1). These results indicate that B. velezensis YC7010-induced systemic resistance to the GPA is a hypersensitive response mainly dependent on higher expression of PAD4 with suppression of BIK1, resulting in more accumulation of hydrogen peroxide, cell death, and callose deposition in Arabidopsis. PMID:28261260

  12. Non-cellulosic polysaccharides from cotton fibre are differently impacted by textile processing.

    Directory of Open Access Journals (Sweden)

    Jean-Luc Runavot

    Full Text Available Cotton fibre is mainly composed of cellulose, although non-cellulosic polysaccharides play key roles during fibre development and are still present in the harvested fibre. This study aimed at determining the fate of non-cellulosic polysaccharides during cotton textile processing. We analyzed non-cellulosic cotton fibre polysaccharides during different steps of cotton textile processing using GC-MS, HPLC and comprehensive microarray polymer profiling to obtain monosaccharide and polysaccharide amounts and linkage compositions. Additionally, in situ detection was used to obtain information on polysaccharide localization and accessibility. We show that pectic and hemicellulosic polysaccharide levels decrease during cotton textile processing and that some processing steps have more impact than others. Pectins and arabinose-containing polysaccharides are strongly impacted by the chemical treatments, with most being removed during bleaching and scouring. However, some forms of pectin are more resistant than others. Xylan and xyloglucan are affected in later processing steps and to a lesser extent, whereas callose showed a strong resistance to the chemical processing steps. This study shows that non-cellulosic polysaccharides are differently impacted by the treatments used in cotton textile processing with some hemicelluloses and callose being resistant to these harsh treatments.

  13. PARAMETER ESTIMATION IN NON-HOMOGENEOUS BOOLEAN MODELS: AN APPLICATION TO PLANT DEFENSE RESPONSE

    Directory of Open Access Journals (Sweden)

    Maria Angeles Gallego

    2014-11-01

    Full Text Available Many medical and biological problems require to extract information from microscopical images. Boolean models have been extensively used to analyze binary images of random clumps in many scientific fields. In this paper, a particular type of Boolean model with an underlying non-stationary point process is considered. The intensity of the underlying point process is formulated as a fixed function of the distance to a region of interest. A method to estimate the parameters of this Boolean model is introduced, and its performance is checked in two different settings. Firstly, a comparative study with other existent methods is done using simulated data. Secondly, the method is applied to analyze the longleaf data set, which is a very popular data set in the context of point processes included in the R package spatstat. Obtained results show that the new method provides as accurate estimates as those obtained with more complex methods developed for the general case. Finally, to illustrate the application of this model and this method, a particular type of phytopathological images are analyzed. These images show callose depositions in leaves of Arabidopsis plants. The analysis of callose depositions, is very popular in the phytopathological literature to quantify activity of plant immunity.

  14. Influence of type I IFN signaling on anti-MOG antibody-mediated demyelination.

    Science.gov (United States)

    Berg, Carsten Tue; Khorooshi, Reza; Asgari, Nasrin; Owens, Trevor

    2017-06-24

    Antibodies with specificity for myelin oligodendrocyte glycoprotein (MOG) are implicated in multiple sclerosis and related diseases. The pathogenic importance of anti-MOG antibody in primary demyelinating pathology remains poorly characterized. The objective of this study is to investigate whether administration of anti-MOG antibody would be sufficient for demyelination and to determine if type I interferon (IFN) signaling plays a similar role in anti-MOG antibody-mediated pathology, as has been shown for neuromyelitis optica-like pathology. Purified IgG2a monoclonal anti-MOG antibody and mouse complement were stereotactically injected into the corpus callosum of wild-type and type I IFN receptor deficient mice (IFNAR1-KO) with and without pre-established experimental autoimmune encephalomyelitis (EAE). Anti-MOG induced complement-dependent demyelination in the corpus callosum of wild-type mice and did not occur in mice that received control IgG2a. Deposition of activated complement coincided with demyelination, and this was significantly reduced in IFNAR1-KO mice. Co-injection of anti-MOG and complement at onset of symptoms of EAE induced similar levels of callosal demyelination in wild-type and IFNAR1-KO mice. Anti-MOG antibody and complement was sufficient to induce callosal demyelination, and pathology was dependent on type I IFN. Induction of EAE in IFNAR1-KO mice overcame the dependence on type I IFN for anti-MOG and complement-mediated demyelination.

  15. Involvement of salicylic acid, glutathione and protein S-thiolation in plant cell death-mediated defence response of Mesembryanthemum crystallinum against Botrytis cinerea.

    Science.gov (United States)

    Kuźniak, Elżbieta; Kaźmierczak, Andrzej; Wielanek, Marzena; Głowacki, Rafał; Kornas, Andrzej

    2013-02-01

    The response of Mesembryanthemum crystallinum plants performing C3 photosynthesis and crassulacean acid metabolism (CAM) to the non-host necrotrophic pathogen Botrytis cinerea was analyzed at the local and systemic levels. The induction of programmed cell death, lignin and callose deposition, changes in salicylic acid, glutathione and cysteinylglycine pools as well as the content of thiolated proteins were studied. The infected C3 and CAM plants exhibited hypersensitive-like defence response, however fluorescence staining with acridine orange and ethidium bromide revealed programmed cell death events in C3 plants only. The local immune response was not related to callose and lignin deposition. In the infected plants, salicylic acid, glutathione and cysteinylglycine, the first product of glutathione catabolism, as well as protein S-thiolation, predominantly S-glutathionylation, contributed to local defence at sites of inoculation. They (except protein thiolation) were also active in the establishment of systemic acclimation response monitored in the non-treated upper leaves. The extent to which they were involved in the local and systemic responses induced by B. cinerea differed in C3 and CAM plants. The accumulation of free salicylic acid, both in treated and upper leaves of the infected plants, was much more pronounced in CAM plants. The results have been discussed with respect to redox regulations in defence against necrotrophic pathogens and to stress acclimation. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  16. Cell wall matrix polysaccharide distribution and cortical microtubule organization: two factors controlling mesophyll cell morphogenesis in land plants.

    Science.gov (United States)

    Sotiriou, P; Giannoutsou, E; Panteris, E; Apostolakos, P; Galatis, B

    2016-03-01

    This work investigates the involvement of local differentiation of cell wall matrix polysaccharides and the role of microtubules in the morphogenesis of mesophyll cells (MCs) of three types (lobed, branched and palisade) in the dicotyledon Vigna sinensis and the fern Asplenium nidus. Homogalacturonan (HGA) epitopes recognized by the 2F4, JIM5 and JIM7 antibodies and callose were immunolocalized in hand-made leaf sections. Callose was also stained with aniline blue. We studied microtubule organization by tubulin immunofluorescence and transmission electron microscopy. In both plants, the matrix cell wall polysaccharide distribution underwent definite changes during MC differentiation. Callose constantly defined the sites of MC contacts. The 2F4 HGA epitope in V. sinensis first appeared in MC contacts but gradually moved towards the cell wall regions facing the intercellular spaces, while in A. nidus it was initially localized at the cell walls delimiting the intercellular spaces, but finally shifted to MC contacts. In V. sinensis, the JIM5 and JIM7 HGA epitopes initially marked the cell walls delimiting the intercellular spaces and gradually shifted in MC contacts, while in A. nidus they constantly enriched MC contacts. In all MC types examined, the cortical microtubules played a crucial role in their morphogenesis. In particular, in palisade MCs, cortical microtubule helices, by controlling cellulose microfibril orientation, forced these MCs to acquire a truncated cone-like shape. Unexpectedly in V. sinensis, the differentiation of colchicine-affected MCs deviated completely, since they developed a cell wall ingrowth labyrinth, becoming transfer-like cells. The results of this work and previous studies on Zea mays (Giannoutsou et al., Annals of Botany 2013; 112: : 1067-1081) revealed highly controlled local cell wall matrix differentiation in MCs of species belonging to different plant groups. This, in coordination with microtubule-dependent cellulose microfibril

  17. Sclerosis: Implications for Interhemispheric Communication

    Directory of Open Access Journals (Sweden)

    A. Lunardelli

    2014-01-01

    Full Text Available We report a case of a 47-year-old woman with 35-year history of multiple sclerosis, who showed alien hand signs, a rare behavioural disorder that involves unilateral goal-directed movements that are contrary to the individual's intention. Alien hand syndrome has been described in multiple sclerosis (MS only occasionally and is generally suggestive of callosal disconnection. The patient presented also with bilateral limb apraxia and left hand agraphia, raising the possibility of cortical dysfunction or disconnection, in addition to corpus callosum and white matter involvement. Her specific pattern of symptoms supports the role of the corpus callosum in interhemispheric communication for complex as well as fine motor activities and may indicate that it can serve as both an inhibitory and excitatory function depending on task demands.

  18. Corpus callosotomy in children and the disconnection syndromes: a review.

    Science.gov (United States)

    Jea, Andrew; Vachhrajani, Shobhan; Widjaja, Elysa; Nilsson, Daniel; Raybaud, Charles; Shroff, Manohar; Rutka, James T

    2008-06-01

    Disconnection syndromes following corpus callosotomy represent complex and variably expressed groupings of signs and symptoms affecting motor control, spatial orientation, vision, hearing, and language. Little is known, however, about the functional topography of callosal fiber pathways. In addition, most published case reports and case series of corpus callosotomy seldom report neurological deficits. We sought to categorize these deficits based on surgical anatomy. We comprehensively reviewed the literature and described, compiled, and tabulated the most common disconnection syndromes complicating corpus callosotomy. We depict the topography of the cerebral cortex and associated commissural fibers of the corpus callosum through illustrations and diffusion tensor imaging tractography. Anatomical classification of disconnection syndromes will provide great value to neurosurgeons embarking on callosotomy, whether partial or complete. Such information will apply to procedures performed for epilepsy and to procedures where the corpus callosum is sectioned for access to lesions within the ventricular system.

  19. Intracranial lipomas (lipomatous hamartomas): Clinical and computerized tomographic findings in 9 cases

    Energy Technology Data Exchange (ETDEWEB)

    Riffel, B.; Thron, A.

    1981-11-01

    By computed tomography intracranial lipomas can be detected in nearly 0.1% of the cases, including very small lesions. The tumorlike malformation should be classified as a hamartoma, e.g. as a maldifferentiation of primarily non-neoplastic tissue. The preferential location is the midline region; a pathogenetic relation to dysraphic disorders is possible. 7 of the 9 cases presented have a lipomatous hamartoma of the corpus callosum or show involvement of this region; in 5 cases additional lipomatous nodules of the ventricular chorioid plexus could be demonstrated uni- or bilaterally. In agreement with the literature, epilepsy and mental disturbances are frequent also in our cases of lipoma of the corpus callosum. A callosal disconnection syndrome could not be demonstrated in the two patients thoroughly examined. Clinical and CT-findings are discussed with regard to pathogenesis and pathological significance of this complex malformation.

  20. Decreased Interhemispheric Coordination in Schizophrenia: A Resting State fMRI Study

    Science.gov (United States)

    Hoptman, Matthew J.; Zuo, Xi-Nian; D’Angelo, Debra; Mauro, Cristina J.; Butler, Pamela D.; Milham, Michael P.; Javitt, Daniel C.

    2012-01-01

    Schizophrenia has been increasingly conceptualized as a disorder of brain connectivity, in large part due to findings emerging from white matter and functional connectivity (FC) studies. This work has focused primarily on within-hemispheric connectivity, however some evidence has suggested abnormalities in callosal structure and interhemispheric interaction. Here we examined functional connectivity between homotopic points in the brain using a technique called voxel-mirrored homotopic connectivity (VMHC). We performed VMHC analyses on resting state fMRI data from 23 healthy controls and 25 patients with schizophrenia or schizoaffective disorder. We found highly significant reductions in VMHC in patients for a number of regions, particularly the occipital lobe, the thalamus, and the cerebellum. No regions of increased VMHC were detected in patients. VMHC in the postcentral gyrus extending into the precentral gyrus was correlated with PANSS Total scores. These results show substantial impairment of interhemispheric coordination in schizophrenia. PMID:22910401

  1. Effect of lead on root growth

    Directory of Open Access Journals (Sweden)

    Mouna eFAHR

    2013-06-01

    Full Text Available Lead (Pb is one of the most widespread heavy metal contaminants in soils. It is highly toxic to living organism. Pb has no biological function but can cause morphological, physiological and biochemical dysfunctions in plants. Plants have developed a wide range of tolerance mechanisms that are activated in response to lead exposure. Pb affects plants primarily through their root systems. Plant roots rapidly respond either (i by the synthesis and deposition of callose, creating a barrier that stops lead entering (ii through the uptake of large amounts of Pb and its sequestration in the vacuole accompanied by changes in root growth and branching pattern or (iii by its translocation to the aboveground parts of plant in the case of hyperaccumulators plants. Here we review the interactions of roots with the presence of Pb in the rhizosphere and the effect of Pb on the physiological and biochemical mechanisms of root development.

  2. Involuntary masturbation and hemiballismus after bilateral anterior cerebral artery infarction.

    Science.gov (United States)

    Bejot, Yannick; Caillier, Marie; Osseby, Guy-Victor; Didi, Roy; Ben Salem, Douraied; Moreau, Thibault; Giroud, Maurice

    2008-02-01

    Ischemia of the areas supplied by the anterior cerebral artery is relatively uncommon. In addition, combined hemiballismus and masturbation have rarely been reported in patients with cerebrovascular disease. We describe herein a 62-year-old right-handed man simultaneously exhibiting right side hemiballismus and involuntary masturbation with the left hand after bilateral infarction of the anterior cerebral artery territory. Right side hemiballismus was related to the disruption of afferent fibers from the left frontal lobe to the left subthalamic nucleus. Involuntary masturbation using the left hand was exclusively linked to a callosal type of alien hand syndrome secondary to infarction of the right side of the anterior corpus callosum. After 2 weeks, these abnormal behaviours were completely extinguished. This report stresses the wide diversity of clinical manifestations observed after infarction of the anterior cerebral artery territory.

  3. [Infarct in the area of the left anterior cerebral artery. II. Language disorders].

    Science.gov (United States)

    Bogousslavsky, J; Assal, G; Regli, F

    1987-01-01

    Language disturbances and other neuropsychological dysfunctions were evaluated in 10 right-handed patients with left anterior cerebral artery (ACA) infarcts with CT correlation. Transcortical motor aphasia was present in 4 cases, related to involvement of the supplementary motor area (SMA) or the underlying and immediately anterior white matter. In 4 patients with sparing of the SMA but with involvement of the cingulate region, only alterations of verbal memory were found. Sensory or mixed transcortical aphasia was not observed, in any of the patients, including those in whom the supplementary sensory area (SSA) or the underlying white matter were involved, casting doubt upon the presumed receptive role in language function attributed to the SSA by some authors. Buccolingual-facial apraxia was related to subcortical lesions. A callosal disconnection syndrome was uncommon (2 patients) and no hemi-neglect was encountered, even in those cases with cingulate involvement.

  4. Alien Hand Syndrome.

    Science.gov (United States)

    Hassan, Anhar; Josephs, Keith A

    2016-08-01

    Alien hand syndrome (AHS) is a rare disorder of involuntary limb movement together with a sense of loss of limb ownership. It most commonly affects the hand, but can occur in the leg. The anterior (frontal, callosal) and posterior variants are recognized, with distinguishing clinical features and anatomical lesions. Initial descriptions were attributed to stroke and neurosurgical operations, but neurodegenerative causes are now recognized as most common. Structural and functional imaging and clinical studies have implicated the supplementary motor area, pre-supplementary motor area, and their network connections in the frontal variant of AHS, and the inferior parietal lobule and connections in the posterior variant. Several theories are proposed to explain the pathophysiology. Herein, we review the literature to update advances in the understanding of the classification, pathophysiology, etiology, and treatment of AHS.

  5. Alien hand and leg as the presenting feature of probable sporadic Creutzfeldt-Jakob disease: A rare presentation of a rare disease.

    Science.gov (United States)

    Kumawat, Banshi Lal; Sharma, Chandra Mohan; Nath, Kunal; Acharya, Mihir; Khandelwal, Dinesh; Jain, Deepak

    2015-01-01

    Sporadic Creutzfeldt-Jakob disease (sCJD) can have varied clinical presentation depending upon the genotype at codon 129. The common presenting clinical features of sCJD are rapid onset cognitive impairment, ataxia, psychosis and visual signs (field defects, distortion, cortical blindness). Alien limb sign was first described in patients with corpus callosal tumors and later with other neurodegenerative conditions like corticobasal degeneration. Alien hand complaints as the presenting feature of sCJD has been described in literature, but simultaneous alien hand and leg has been rarely described as presenting feature of sCJD. We describe here a case of a 55-year-old man who presented with progressive left alien hand and leg as the sole clinical manifestation of probable sCJD.

  6. Rice Seed Priming with Picomolar Rutin Enhances Rhizospheric Bacillus subtilis CIM Colonization and Plant Growth.

    Directory of Open Access Journals (Sweden)

    Akanksha Singh

    Full Text Available The effect of rutin, a bioflavonoid on the growth and biofilm formation of Bacillus subtilis strain CIM was investigated. In addition to swimming, swarming, and twitching potentials of B. subtilis CIM (BS, one picomolar (1 pM of rutin was also observed to boost the biofilm forming ability of the bacterium. Bio-priming of rice seeds with BS and rutin not only augmented root and shoot lengths but also the photosynthetic pigments like chlorophyll and carotenoid. Similarly, high accumulation of phenolic and flavonoid contents was observed in the leaves. Fluorescent microscopic images revealed that BS plus rutin enhanced callose deposition in the leaves. It was also established that the least formation of reactive oxygen species in BS plus rutin treated rice plants was due to higher free radicals scavenging activity and total antioxidant potential. The results highlight chemo attractant nature of BS towards rutin, which by enhancing biofilm formation and root colonization indirectly strengthened the plants' defensive state.

  7. Differentiation of conductive cells: a matter of life and death.

    Science.gov (United States)

    Heo, Jung-Ok; Blob, Bernhard; Helariutta, Ykä

    2017-02-01

    Two major conducting tissues in plants, phloem and xylem, are composed of highly specialized cell types adapted to long distance transport. Sieve elements (SEs) in the phloem display a thick cell wall, callose-rich sieve plates and low cytoplasmic density. SE differentiation is driven by selective autolysis combined with enucleation, after which the plasma membrane and some organelles are retained. By contrast, differentiation of xylem tracheary elements (TEs) involves complete clearance of the cellular components by programmed cell death followed by autolysis of the protoplast; this is accompanied by extensive deposition of lignin and cellulose in the cell wall. Emerging molecular data on TE and SE differentiation indicate a central role for NAC and MYB type transcription factors in both processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Cranial MRI in the Nijmegen breakage syndrome

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    Bekiesinska-Figatowska, M. [Department of Diagnostic Imaging, Central Railway Hospital, Warsaw (Poland); Chrzanowska, K.H.; Krajewska-Walasek, M. [Department of Medical Genetics, Children' s Memorial Health Institute, Warsaw (Poland); Sikorska, J.; Walecki, J. [Department of Diagnostic Imaging, Medical Centre for Postgraduate Education, Warsaw (Poland); Jozwiak, S. [Department of Neurology, Children' s Memorial Health Institute, Warsaw (Poland); Kleijer, W.J. [Department of Clinical Genetics, Erasmus University Rotterdam (Netherlands)

    2000-01-01

    We present the results of MRI examinations in ten patients with documented Nijmegen breakage syndrome (NBS), aged 1.75-19 years. T1-, Proton-Density- and T2-weighted spin-echo sequences were performed in three planes. All patients showed microcephaly with decreased size of the frontal lobes and narrow frontal horns. In four patients agenesis of the posterior part of the corpus callosum was found, with colpocephaly and temporal horns dilatation. In one patient callosal hypoplasia was accompanied by abnormal cerebrospinal fluid spaces and wide cerebral cortex, suspicious of pachygyria. Sinusitis was present in all ten patients, as a result of primary immunodeficiency. As in ataxia teleangiectasia and other breakage syndromes, patients with NBS show an inherited susceptibility to malignancy and hypersensitivity to X- and {gamma}-radiation. CT is therefore contraindicated in these patients and MRI should be the method of choice for diagnostic imaging. (orig.)

  9. Atypical brain laterality in adults with ADHD during dichotic listening for emotional intonation and words.

    Science.gov (United States)

    Hale, T Sigi; Zaidel, Eran; McGough, James J; Phillips, Joseph M; McCracken, James T

    2006-01-01

    Few studies directly examined the nature of hemispheric specialization and interaction in ADHD. The present experiment investigated left/right brain dynamics in unmedicated right handed adults with ADHD (n = 19) and in controls (n = 19), using a dichotic listening task to assess hemispheric differences in word and emotion recognition. We also assessed how focusing attention on a single ear modulated lateralized performance and affected cross-callosal interference effects. Analysis of variance indicated that ADHD subjects showed reduced left hemisphere specialization, were better at processing emotions, and worse at processing words compared to controls. These differences were eliminated during focused attention. Finally, during presumed right hemisphere processing of linguistic stimuli, subjects with ADHD showed reduced left hemisphere interference. We concluded that ADHD subjects demonstrated greater right hemisphere and reduced left hemisphere contribution during this task relative to controls. We posit that these hemispheric differences were due to management or use of available cognitive resources rather than inherent capacity.

  10. Social narratives in agenesis of the corpus callosum: linguistic analysis of the Thematic Apperception Test.

    Science.gov (United States)

    Turk, Anne A; Brown, Warren S; Symington, Melissa; Paul, Lynn K

    2010-01-01

    In a previous study, individuals with agenesis of the corpus callosum (ACC) with normal intelligence provided narratives to pictures from the Thematic Apperception Test (TAT) that were limited in logical coherence and social awareness. The current study examined the linguistic content of TAT stories from 22 persons with isolated complete ACC compared to 30 IQ- and age-matched controls using the Linguistic Inquiry and Word Count (Pennebaker et al., 2001). Compared to controls, individuals with ACC used fewer words pertaining to emotionality, cognitive processes, and social processes. They also used relatively more present tense verbs and first person pronouns. These findings suggest that callosal agenesis results in deficiencies in imagining and inferring the mental, emotional, and social functioning of others as implied by TAT pictures, and in translating this content into a narrative. In addition, ACC affects the grammatical structure of verbally produced narratives, with greater emphasis on the present tense and the first person.

  11. Links between early pollen development and aperture pattern in monocots.

    Science.gov (United States)

    Nadot, S; Forchioni, A; Penet, L; Sannier, J; Ressayre, A

    2006-08-01

    Although the pollen grains produced in monocots are predominantly monosulcate (or monoporate), other aperture types are also found within this taxonomic group, such as the trichotomosulcate, inaperturate, zonaperturate, di-, or triaperturate types. The aperture pattern is determined during the young-tetrad stage of pollen development and it is known that some features of microsporogenesis can constrain the aperture type. For example, trichotomosulcate pollen is always associated with simultaneous cytokinesis, a condition considered as derived in the monocots. Our observations of the microsporogenesis pathway in a range of monocot species show that this pathway is surprisingly variable. Our results, however preliminary, reveal that variation in microsporogenesis concerns not only cytokinesis but also callose deposition among the microspores and shape of the tetrads. The role played by these features in aperture pattern determination is discussed.

  12. Functional brain asymmetry, attentional modulation, and interhemispheric transfer in boys with Tourette syndrome

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Lundervold, Arvid; Grüner, Renate

    2007-01-01

    on the right ear stimulus in the dichotic listening situation is thought to involve the same prefrontal attentional and executive functions that are involved in the suppression of tics, whereas, performance when focusing attention on the left ear stimulus additionally involves a callosal transfer...... of information. In light of presumed disturbances in transfer of information across the corpus callosum, we hypothesized that children with TS would, however, have difficulty modulating the functional lateralization that ensues through a shift of attention to the left side. This hypothesis was tested...... by exploring the correlations between CC size and left ear score in the forced-left condition. Twenty boys with TS were compared with 20 age- and handedness-matched healthy boys. Results indicated similar performance in the TS and HC groups for lateralization of hemispheric function. TS subjects were also able...

  13. Types of Pollen Dispersal Units in Orchids, and their Consequences for Germination and Fertilization

    Science.gov (United States)

    Pacini, Ettore; Hesse, Michael

    2002-01-01

    The various pollen dispersal units (PDU) found in orchids are discussed together with possible evolutionary trends and the consequences for germination and fertilization. Orchids with monad and tetrad pollen form more complex dispersal units by means of pollenkitt, elastoviscin, a callosic wall, common walls or a combination of these. Evolutionary trends include (1) from pollenkitt to elastoviscin; (2) from monad to tetrads and multiples of tetrads; (3) from partially dehydrated (30 %) pollen; and (4) from monad pollen to PDUs with many pollen grains. The biological consequences concern both male and female reproductive systems. Some features of the male side are present in all orchids irrespective of the pollen dispersal unit, whereas other characters are found only in orchids with pollinia; the same applies for the female counterpart. Pollen grains of orchids with pollinia germinate at least 24 h after pollination because the pollen grains/tetrads must swell and make space for the growth of pollen tubes. PMID:12102520

  14. Corpus callosum tissue loss and development of motor and global cognitive impairment: the LADIS study.

    Science.gov (United States)

    Frederiksen, Kristian S; Garde, Ellen; Skimminge, Arnold; Barkhof, Frederik; Scheltens, Philip; van Straaten, Elisabeth C W; Fazekas, Franz; Baezner, Hansjörg; Verdelho, Ana; Ferro, José M; Erkinjuntti, Timo; Jokinen, Hanna; Wahlund, Lars-Olof; O'Brien, John T; Basile, Anna M; Pantoni, Leonardo; Inzitari, Domenico; Waldemar, Gunhild

    2011-01-01

    To examine the impact of corpus callosum (CC) tissue loss on the development of global cognitive and motor impairment in the elderly. This study was based on the Leukoaraiosis and Disability (LADIS) study. Assessment of cognitive and motor functions and magnetic resonance imaging (MRI) were done at baseline and at a 3-year follow-up in nondemented elderly subjects. 328 of 639 LADIS subjects had MRIs at baseline and at the 3-year follow-up, which allowed for assessment of CC. Logistic regression revealed differential tissue loss rates in posterior CC in subjects converting to dementia, compared to nonconverters (p CC tissue loss was significantly correlated with self-perceived memory impairment in nonconverters (p CC tissue loss was also significantly associated with impaired single leg stance time (p CC supports the role of callosal tissue loss in the development of global cognitive as well as motor impairment. Copyright © 2012 S. Karger AG, Basel.

  15. Peptidoglycan and muropeptides from pathogens Agrobacterium and Xanthomonas elicit plant innate immunity

    DEFF Research Database (Denmark)

    Erbs, Gitte; Silipo, Alba; Aslam, Shazia

    2008-01-01

    Peptidoglycan (PGN) is a unique and essential structural part of the bacterial cell wall. PGNs from two contrasting Gram-negative plant pathogenic bacteria elicited components characteristic of the innate immune system in Arabidopsis thaliana, such as transcription of the defense gene PR1......, oxidative burst, medium alkalinization, and formation of callose. Highly purified muropeptides from PGNs were more effective elicitors of early defense responses than native PGN. Therefore, PGN and its constituents represent a Microbe-Associated Molecular Pattern (MAMP) in plant-bacterial interactions. PGN...... and muropeptides from aggressive Xanthomonas campestris pv. campestris were significantly more active than those from Agrobacterium tumefaciens, which must maintain host cell viability during infection. The structure of muropeptide components and the distinctive differences are described. Differing defense...

  16. Cerebral motor function in very premature-at-birth adolescents: a brain stimulation exploration of kangaroo mother care effects.

    Science.gov (United States)

    Schneider, Cyril; Charpak, Nathalie; Ruiz-Peláez, Juan G; Tessier, Réjean

    2012-10-01

      Given that prematurity has deleterious effects on brain networking development beyond childhood, the study explored whether an early intervention such as Kangaroo Mother Care (KMC) in very preterm preemies could have influenced brain motor function up to adolescence.   Transcranial magnetic stimulation (TMS) was applied over the primary motor cortex (M1) of 39 adolescents born very prematurely (37 weeks' gestational age, >2500 g) to assess the functional integrity of motor circuits in each hemisphere (motor planning) and between hemispheres (callosal function).   All TMS outcomes were similar between KMC and term adolescents, with typical values as in healthy adults, and better than in Controls. KMC adolescents presented faster conduction times revealing more efficient M1 cell synchronization (p motor pathways in the KMC group suggests that the Kangaroo Mother Care positively influenced the premature brain networks and synaptic efficacy up to adolescence. © 2012 The Author(s)/Acta Paediatrica © 2012 Foundation Acta Paediatrica.

  17. Aluminium Toxicity Targets in Plants

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    Sónia Silva

    2012-01-01

    Full Text Available Aluminium (Al is the third most abundant metallic element in soil but becomes available to plants only when the soil pH drops below 5.5. At those conditions, plants present several signals of Al toxicity. As reported by literature, major consequences of Al exposure are the decrease of plant production and the inhibition of root growth. The root growth inhibition may be directly/indirectly responsible for the loss of plant production. In this paper the most remarkable symptoms of Al toxicity in plants and the latest findings in this area are addressed. Root growth inhibition, ROS production, alterations on root cell wall and plasma membrane, nutrient unbalances, callose accumulation, and disturbance of cytoplasmic Ca2+ homeostasis, among other signals of Al toxicity are discussed, and, when possible, the behavior of Al-tolerant versus Al-sensitive genotypes under Al is compared.

  18. Histogenesis of potato light sprouts in healthy plants and those infected with potato leaf roll virus

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    Grażyna Garbaczewska

    2013-12-01

    Full Text Available Developmental stages of potato (Solanum tuberosum light sprouts in healthy plants and those infected with potato leaf roll virus (PLRV have been distinguished. Potato light sprouts from healthy tubers differentiate in the early stages to the apical and basal parts, which are characterized by distinct dynamics of growth. Ultrastructural examination of apex meristem and phloem ontogeny was carried out for healthy plants. In the development of potato light sprouts of plants infected with PLRV a great many anomalies have been described. Three types of light sprouts developed from infected tubers. Anatomical investigations indicated a rapid growth of the number of necroses in the phloem, and submicroscopic observations showed the presence of virus particles and cytopathological structures: tubular and vesicular structures, paramural bodies and callose deposits. In the companion cells of the phloem the occurrence of very regular inclusions of virus particles was recorded.

  19. Oligodendrocytes in the Mouse Corpus Callosum Maintain Axonal Function by Delivery of Glucose

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    Niklas Meyer

    2018-02-01

    Full Text Available In the optic nerve, oligodendrocytes maintain axonal function by supplying lactate as an energy substrate. Here, we report that, in acute brain slices of the mouse corpus callosum, exogenous glucose deprivation (EGD abolished compound action potentials (CAPs, which neither lactate nor pyruvate could prevent. Loading an oligodendrocyte with 20 mM glucose using a patch pipette prevented EGD-mediated CAP reduction in about 70% of experiments. Loading oligodendrocytes with lactate rescued CAPs less efficiently than glucose. In mice lacking connexin 47, oligodendrocyte filling with glucose did not prevent CAP loss, emphasizing the importance of glial networks for axonal energy supply. Compared with the optic nerve, the astrocyte network in the corpus callosum was less dense, and loading astrocytes with glucose did not prevent CAP loss during EGD. We suggest that callosal oligodendrocyte networks provide energy to sustain axonal function predominantly by glucose delivery, and mechanisms of metabolic support vary across different white matter regions.

  20. Do Cecidomyiidae galls of Aspidosperma spruceanum (Apocynaceae) fit the pre-established cytological and histochemical patterns?

    Science.gov (United States)

    Oliveira, Denis Coelho; Magalhães, Thiago Alves; Carneiro, Renê Gonçalves Silva; Alvim, Marina Neiva; Isaias, Rosy Mary Santos

    2010-06-01

    Cecidomyiidae galls commonly present a zonation of tissues with lignified cell layers externally limiting a reserve tissue and internally limiting a specialized nutritive tissue next to the larval chamber. The cytological aspects of this specialized tissue indicate high metabolic activity as well as carbohydrate accumulation. In Aspidosperma spruceanum-Cecidomyiidae gall system, ultrastructural and histochemical investigations corroborated this pattern and also revealed the storage of proteins in the nutritive cells. Reactive oxygen species (ROS), callose, and pectin accumulation were related to the feeding activity of the galling herbivore. Phosphorylase, glucose-6-phosphatase, acid phosphatases, invertases, and sucrose synthase activities were detected for the first time, in the Neotropical region, and discussed in relation to gall maintenance and the feeding activity of the Cecidomyiidae.

  1. Chitosan as a MAMP, searching for a PRR

    Science.gov (United States)

    Faoro, Franco

    2009-01-01

    Chitosan, a deacetylated chitin derivative, behaves like a general elicitor, inducing a non-host resistance and priming a systemic acquired immunity. The defence responses elicited by chitosan include rising of cytosolic H+ and Ca2+, activation of MAP-kinases, callose apposition, oxidative burst, hypersensitive response (HR), synthesis of abscissic acid (ABA), jasmonate, phytoalexins and pathogenesis related (PR) proteins. Putative receptors for chitosan are a chitosan-binding protein, recently isolated, and possibly the chitin elicitor-binding protein (CEBiP). Nevertheless, it must be pointed out that biological activity of chitosan, besides the plant model, strictly depends on its physicochemical properties (deacetylation degree, molecular weight and viscosity), and that there is a threshold for chitosan concentration able to switch the induction of a cell death programme into necrotic cell death (cytotoxicity). PMID:19704712

  2. Reduced fractional anisotropy in the anterior corpus callosum is associated with reduced speech fluency in persistent developmental stuttering.

    Science.gov (United States)

    Civier, Oren; Kronfeld-Duenias, Vered; Amir, Ofer; Ezrati-Vinacour, Ruth; Ben-Shachar, Michal

    2015-04-01

    Developmental stuttering is a speech disorder that severely limits one's ability to communicate. White matter anomalies were reported in stuttering, but their functional significance is unclear. We analyzed the relation between white matter properties and speech fluency in adults who stutter (AWS). We used diffusion tensor imaging with tract-based spatial statistics, and examined group differences as well as correlations with behavioral fluency measures. We detected a region in the anterior corpus callosum with significantly lower fractional anisotropy in AWS relative to controls. Within the AWS group, reduced anisotropy in that region is associated with reduced fluency. A statistically significant interaction was found between group and age in two additional regions: the left Rolandic operculum and the left posterior corpus callosum. Our findings suggest that anterior callosal anomaly in stuttering may represent a maladaptive reduction in interhemispheric inhibition, possibly leading to a disadvantageous recruitment of right frontal cortex in speech production. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Chitosan in Plant Protection

    Directory of Open Access Journals (Sweden)

    Abdelbasset El Hadrami

    2010-03-01

    Full Text Available Chitin and chitosan are naturally-occurring compounds that have potential in agriculture with regard to controlling plant diseases. These molecules were shown to display toxicity and inhibit fungal growth and development. They were reported to be active against viruses, bacteria and other pests. Fragments from chitin and chitosan are known to have eliciting activities leading to a variety of defense responses in host plants in response to microbial infections, including the accumulation of phytoalexins, pathogen-related (PR proteins and proteinase inhibitors, lignin synthesis, and callose formation. Based on these and other proprieties that help strengthen host plant defenses, interest has been growing in using them in agricultural systems to reduce the negative impact of diseases on yield and quality of crops. This review recapitulates the properties and uses of chitin, chitosan, and their derivatives, and will focus on their applications and mechanisms of action during plant-pathogen interactions.

  4. Tactile agnosia and tactile aphasia: symptomatological and anatomical differences.

    Science.gov (United States)

    Endo, K; Miyasaka, M; Makishita, H; Yanagisawa, N; Sugishita, M

    1992-09-01

    Two patients with tactile naming disorders are reported. Case 1 (right hand tactile agnosia due to bilateral cerebral infarction) differentiated tactile qualities of objects normally, but could neither name nor categorize the objects. Case 2 (bilateral tactile aphasia after operation of an epidural left parietal haematoma) had as severe a tactile naming disturbance as Case 1, but could categorize objects normally, demonstrating that tactile recognition was preserved. Case 1 may be the first case of tactile agnosia clearly differentiated from tactile aphasia. CT scans of Case 1 revealed lesions in the left angular gyrus, and in the right parietal, temporal, and occipital lobes. Case 2 had lesions in the left angular gyrus and of posterior callosal radiations. Our findings suggest that tactile agnosia appears when the somatosensory association cortex is disconnected by a subcortical lesion of the angular gyrus from the semantic memory store located in the inferior temporal lobe, while tactile aphasia represents a tactual-verbal disconnection.

  5. Infarction of the corpus callosum: a retrospective clinical investigation.

    Directory of Open Access Journals (Sweden)

    Shen Li

    Full Text Available The aim of this study was to investigate patients with ischemic infarctions in the territory of the corpus callosum to advance our understanding of this rare stroke subtype by providing comprehensive descriptive and epidemiological data.From January 1, 2010 to June 30, 2014, all cases of acute ischemic stroke diagnosed by clinical manifestation and diffusion weighted imaging in Dalian Municipal Central Hospital were investigated. The patients presenting with corpus callosum infarctions were selected and further allocated into genu and/or body and splenium infarction groups. Proportion, lesion patterns, clinical features, risk factors and etiology of corpus callosum infarction were analyzed.Out of 1,629 cases, 59 patients (3.6% with corpus callosum infarctions were identified by diffusion weighted imaging, including 7 patients who had ischemic lesions restricted to the corpus callosum territory. Thirty six patients had lesions in the splenium (61.0%. Corpus callosum infarction patients suffered from a broad spectrum of symptoms including weakness and/or numbness of the limbs, clumsy speech, and vertigo, which could not be explained by lesions in corpus callosum. A classical callosal disconnection syndrome was found in 2 out of all patients with corpus callosum infarctions. Statistical differences in the risk factor and infarct pattern between the genu and/or body group and splenium group were revealed.Corpus callosum infarction and the callosal disconnection syndrome were generally rare. The most susceptible location of ischemic corpus callosum lesion was the splenium. Splenium infarctions were often associated with bilateral cerebral hemisphere involvement (46.2%. The genu and/or body infarctions were associated with atherosclerosis. The most common cause of corpus callosum infarction probably was embolism.

  6. Histological responses to downy mildew in resistant and susceptible grapevines.

    Science.gov (United States)

    Liu, Ruiqi; Wang, Lan; Zhu, Jiali; Chen, Tingting; Wang, Yuejin; Xu, Yan

    2015-01-01

    Downy mildew in grapevines, caused by Plasmopara viticola, is a very serious disease throughout the grape-producing nations, especially in more humid climates. Downy mildew mainly affects the cultivated varieties of Vitis vinifera. A promising way to minimize or eliminate P. viticola infections is by the adoption of resistant cultivars. Chinese wild grapevines are reported to possess resistance to many fungal diseases. In this study, three Chinese wild grapevines (Vitis pseudoreticulata Baihe-35-1, Vitis davidii var. cyanocarpa Langao-5, and Vitis piasezkii Liuba-8) and a European cultivated variety (V. vinifera cv. Pinot noir) were inoculated with P. viticola, and a histological survey was undertaken. Macroscopic observations revealed no sporulation in V. piasezkii Liuba-8, little sporulation in V. pseudoreticulata Baihe-35-1 and V. davidii var. cyanocarpa Langao-5, but serious sporulation in V. vinifera cv. Pinot noir. Aniline blue staining indicated callose deposition in V. pseudoreticulata Baihe-35-1, V. davidii var. cyanocarpa Langao-5, and V. piasezkii Liuba-8. Cells with distinctive fluorescence were also observed in V. pseudoreticulata Baihe-35-1. After staining with 3,3-diaminobenzidine, production of H₂O₂ was observed early on, after infection in V. davidii var. cyanocarpa Langao-5 and V. piasezkii Liuba-8. No H₂O₂ accumulation was observed in V. vinifera cv. Pinot noir. It is concluded that V. piasezkii Liuba-8 should be classified as "highly resistant" to downy mildew, V. pseudoreticulata Baihe-35-1 and V. davidii var. cyanocarpa Langao-5 as "resistant," and V. vinifera Pinot noir as "susceptible." The possible roles of stomatal callose deposition in the defense r6eactions of the mildew-resistant grapevines are discussed.

  7. White matter changes in early phase schizophrenia and cannabis use: an update and systematic review of diffusion tensor imaging studies.

    Science.gov (United States)

    Cookey, Jacob; Bernier, Denise; Tibbo, Philip G

    2014-07-01

    The impact of cannabis use on the brain tissue is still unclear, both in the healthy developing brain and in people with schizophrenia. The focus of this review is on white matter, the primary connective infrastructure of the brain. We systematically reviewed diffusion tensor imaging (DTI) studies of early phase schizophrenia (illness effect), of cannabis use in otherwise healthy brains (drug effect), and of early phase schizophrenia with cannabis use (combined effects). Studies had to include a healthy, non-cannabis using, control group as well as report on fractional anisotropy as it is the most commonly used DTI index. We excluded cohorts with heavy alcohol or illicit drug use and studies with a sample size of less than 20 in the clinical group. We retained 17 studies of early phase schizophrenia, which together indicate deficits in white matter integrity observed in all fiber tract families, but most frequently in association, callosal and projection fibers. In otherwise healthy cannabis users (2 studies), deficits in white matter tracts were reported mainly in callosal fibers, but also in projection and limbic fibers. In cannabis users with early phase schizophrenia (1 study), deficits in white matter integrity were also observed in all fiber tract families, except for limbic fibers. The current literature points to several families of white matter tracts being differentially affected in early phase schizophrenia. Further work is required to reveal the impact of cannabis use in otherwise healthy people as well as those with schizophrenia. Paucity of available studies as well as restricting analysis to FA values represent the main limitations of this review. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Exogenous application of methyl jasmonate induces a defense response and resistance against Sclerotinia sclerotiorum in dry bean plants.

    Science.gov (United States)

    Oliveira, Marília Barros; Junior, Murillo Lobo; Grossi-de-Sá, Maria Fátima; Petrofeza, Silvana

    2015-06-15

    Sclerotinia sclerotiorum (Lib.) de Bary is a necrotrophic fungal pathogen that causes a disease known as white mold, which is a major problem for dry bean (Phaseolus vulgaris L.) and other crops in many growing areas in Brazil. To investigate the role of methyl jasmonate (MeJA) in defending dry bean plants against S. sclerotiorum, we used suppression subtractive hybridization (SSH) of cDNA and identified genes that are differentially expressed during plant-pathogen interactions after treatment. Exogenous MeJA application enhanced resistance to the pathogen, and SSH analyses led to the identification of 94 unigenes, presumably involved in a variety of functions, which were classified into several functional categories, including metabolism, signal transduction, protein biogenesis and degradation, and cell defense and rescue. Using RT-qPCR, some unigenes were found to be differentially expressed in a time-dependent manner in dry bean plants during the interaction with S. sclerotiorum after MeJA treatment, including the pathogenesis-related protein PR3 (chitinase), PvCallose (callose synthase), PvNBS-LRR (NBS-LRR resistance-like protein), PvF-box (F-box family protein-like), and a polygalacturonase inhibitor protein (PGIP). Based on these expression data, the putative roles of differentially expressed genes were discussed in relation to the disease and MeJA resistance induction. Changes in the activity of the pathogenesis-related proteins β-1,3-glucanase, chitinase, phenylalanine ammonia-lyase, and peroxidase in plants after MeJA treatment and following inoculation of the pathogen were also investigated as molecular markers of induced resistance. Foliar application of MeJA induced partial resistance against S. sclerotiorum in plants as well as a consistent increase in pathogenesis-related protein activities. Our findings provide new insights into the physiological and molecular mechanisms of resistance induced by MeJA in the P. vulgaris-S. sclerotiorum pathosystem

  9. A phylogenetic approach to study the origin and evolution of plasmodesmata-localized Glycosyl Hydrolases family 17

    Directory of Open Access Journals (Sweden)

    Rocio eGaudioso-Pedraza

    2014-05-01

    Full Text Available Colonization of the land by plants required major modifications in cellular structural composition and metabolism. Intercellular communication through plasmodesmata (PD plays a critical role in the coordination of growth and cell activities. Changes in the form, regulation or function of these channels are likely linked to plant adaptation to the terrestrial environments. Constriction of PD aperture by deposition of callose is the best-studied mechanism in PD regulation. Glycosyl hydrolases family 17 (GHL17 are callose degrading enzymes. In Arabidopsis this is a large protein family, few of which have been PD-localized. The objective here is to identify correlations between evolution of this protein family and their role at PD and to use this information as a tool to predict the localization of candidates isolated in a proteomic screen. With this aim, we studied phylogenetic relationship between Arabidopsis GHL17 sequences and those isolated from fungi, green algae, mosses and monocot representatives. Three distinct phylogenetic clades were identified. Clade alpha contained only embryophytes sequences suggesting that this subgroup appeared during land colonization in organisms with functional PD. Accordingly, all PD-associated GHL17 proteins identified so far in Arabidopsis thaliana and Populus are grouped in this ‘embryophytes only’ phylogenetic clade. Next, we tested the use of this knowledge to discriminate between candidates isolated in the PD proteome. Transient and stable expression of GFP protein fusions confirmed PD localization for candidates contained in clade alpha but not for candidates contained in clade beta. Our results suggest that GHL17 membrane proteins contained in the alpha clade evolved and expanded during land colonization to play new roles, among others, in PD regulation.

  10. Occupational Dermatoses among Cottage Industry Workers of Kashmir Valley in North India.

    Science.gov (United States)

    Akhtar, Saniya; Hassan, Iffat; Rasool, Farhan; Bhat, Yasmeen J; Sheikh, Gousia

    2017-01-01

    Cottage industry is usually a small-scale industry operated from home by family members using their own equipment. Kashmir has a unique cottage industry of its own which deals with production of many handicrafts, which may lead to a peculiar pattern of skin diseases in these artisans. Aim: The aim of this study was to find out the pattern of skin disorders in the cottage industry workers of Kashmir valley, with primary focus on the occupation-related dermatoses and to identify the most common cutaneous manifestation in these workers. This was a cross-sectional descriptive study in which 1062 cottage industry workers engaged in different crafts were screened. A detailed history taking and examination was carried out in each worker and the diagnosis was made on clinical grounds. Wherever deemed necessary, relevant investigations were done to establish the nature of the disease. A total of 1062 workers were evaluated for the presence of skin disorders. The male-to-female ratio was 1:1.5. The mean age of the study group was 30.3 years ± 10.79 years, with maximum number of workers (164) belonging to the crewel embroidery industry. The mean duration of work was 6.4 ± 2.08 hours/day. A total of 953 workers (89.7%) had cutaneous manifestations, with callosities being the most common finding seen in 371 workers (35%), followed by cumulative insult dermatitis seen in 201 workers (19%). Cottage industry of Kashmir valley is a unique occupational group where a high percentage of workers had cutaneous manifestations related to their occupation, with callosities being the most common finding. Information and better knowledge regarding these dermatoses are important in devising strategies to improve the health scenario of these workers. Simple measures such as proper use of instruments, use of protective gloves, guarded use of chemicals, and hand washing may be very beneficial in reducing the burden of health problems in these workers.

  11. [Split tibialis posterior tendon transfer on peroneus brevis for equinovarus foot in CP children].

    Science.gov (United States)

    Grzegorzewski, Andrzej; Borowski, Andrzej; Pruszczyński, Błazej; Wranicz, Anna; Domzalski, Marcin; Synder, Marek

    2007-01-01

    Equinovarus deformity of the foot is a result of the muscles imbalance in which inventors of the foot, mostly posterior and anterior tibialis muscle, overpower evertors. In children with cerebral palsy untreated spastic equinovarus deformity may cause severe fixed foot deformity and painful callosities under metatarsal heads and on the lateral side of the foot. The gait pattern becomes less effective and needs more energy. The study group consisted of 154 children with cerebral palsy treated in our Clinic by the multilevel soft tissue surgery. For foot problems 136 children needed surgical intervention. In 19 ambulatory patients, with hemiplegia or diplegia, split tibialis posterior tendon transfer together with tendo Achilles lengthening and plantar aponeurectomy were performed. The study was based on clinical examination, parents' questionnaire, radiology and gait analysis at least one year after surgery. The mean follow up was 4.6 years. The functional improvement was observed in 17 (89%) children with tendon transfer. At the last follow up those patients were brace free, with plantigrade foot while walking (without DAFO orthesis) and normal shoes were used. All painful callosities disappeared. On a standing AP X-ray adequate correction of the hindfoot-forefoot relation was achieved in 14 (74%) cases. Persistent equinovarus deformity over 10 degrees was observed in 2 cases. Those patients underwent additional bone surgery. With a properly planned approach the split tibialis posterior tendon transfer can bring good clinical and functional results in CP children with equinovarus deformation. We recommend this procedure in early stage of the deformity what can eliminate more harmful triple arthrodesis in severe deformities.

  12. Biochemical Basis of Apple Leaf Resistance to Erwinia amylovora Infection

    Directory of Open Access Journals (Sweden)

    Marija Viljevac

    2009-01-01

    Full Text Available Erwinia amylovora is the most frequently found necrogenic bacterium on apple (Malus domestica Borkh. trees, which causes progressive necrosis and blight of host plants. Rapid spread of bacteria through the host tissue can lead to the loss of entire trees in one growing season. In this work, the aim is to investigate long-lasting biochemical responses in leaves of two apple cultivars (Enterprise and Golden delicious. Several histochemical (polyphenols, suberin and callose and biochemical parameters (total polyphenols, superoxide dismutase – SOD, ascorbate peroxidase – APX and guaiacol peroxidase – GPOD were screened 60 days after Erwinia inoculation in order to find their potential correlation with plant resistance mechanisms to the pathogen attack. Differential susceptibility to the pathogen attack observed between the investigated cultivars was in accordance with previous studies that characterized Enterprise as less susceptible and Golden delicious as more susceptible cultivar. Infected leaves of Golden delicious expressed symptoms seen as large brown areas at the abaxial side mostly placed at the leaf margin and necrosis also found peripherally, while damage in Enterprise leaves was observed as small brown spots and sporadic leaf edge necrosis. Increased SOD and GPOD activities combined with decreased polyphenol content as well as wide cuticle suberization in cultivar Enterprise should be considered as reliable biochemical parameters characterizing its ability to develop certain resistance to the pathogen infection. Furthermore, the absence of callose deposition in leaves of Enterprise confirmed our findings that thick suberized cuticle is likely the main defense mechanism that enables long-term efficient protection of apple leaves against biotic stress caused by Erwinia attack.

  13. Potassium phosphite primes defense responses in potato against Phytophthora infestans.

    Science.gov (United States)

    Machinandiarena, Milagros Florencia; Lobato, María Candela; Feldman, Mariana Laura; Daleo, Gustavo Raúl; Andreu, Adriana Balbina

    2012-09-15

    Although phosphite is widely used to protect plants from pathogenic oomycetes on a wide range of horticultural crops, the molecular mechanisms behind phosphite induced resistance are poorly understood. The aim of this work was to assess the effects of potassium phosphite (KPhi) on potato plant defense responses to infection with Phytophtora infestans (Pi). Pathogen development was severely restricted and there was also an important decrease in lesion size in infected KPhi-treated leaves. We demonstrated that KPhi primed hydrogen peroxide and superoxide anion production in potato leaves at 12 h post-inoculation with Pi. Moreover, the KPhi-treated leaves showed an increased and earlier callose deposition as compared with water-treated plants, beginning 48 h after inoculation. In contrast, callose deposition was not detected in water-treated leaves until 72 h after inoculation. In addition, we carried out RNA gel blot analysis of genes implicated in the responses mediated by salicylic (SA) and jasmonic acid (JA). To this end, we examined the temporal expression pattern of StNPR1 and StWRKY1, two transcription factors related to SA pathway, and StPR1 and StIPII, marker genes related to SA and JA pathways, respectively. The expression of StNPR1 and StWRKY1 was enhanced in response to KPhi treatment. In contrast, StIPII was down regulated in both KPhi- and water-treated leaves, until 48 h after infection with Pi, suggesting that the regulation of this gene could be independent of the KPhi treatment. Our results indicate that KPhi primes the plant for an earlier and more intense response to infection and that SA would mediate this response. Copyright © 2012 Elsevier GmbH. All rights reserved.

  14. Repression of Sucrose/Ultraviolet B Light-Induced Flavonoid Accumulation in Microbe-Associated Molecular Pattern-Triggered Immunity in Arabidopsis1[W

    Science.gov (United States)

    Serrano, Mario; Kanehara, Kazue; Torres, Martha; Yamada, Kohji; Tintor, Nico; Kombrink, Erich; Schulze-Lefert, Paul; Saijo, Yusuke

    2012-01-01

    Recognition of microbe-associated molecular patterns (MAMPs) leads to the generation of MAMP-triggered immunity (MTI), which restricts the invasion and propagation of potentially infectious microbes. It has been described that the perception of different bacterial and fungal MAMPs causes the repression of flavonoid induction upon light stress or sucrose application. However, the functional significance of this MTI-associated signaling output remains unknown. In Arabidopsis (Arabidopsis thaliana), FLAGELLIN-SENSING2 (FLS2) and EF-TU RECEPTOR act as the pattern recognition receptors for the bacterial MAMP epitopes flg22 (of flagellin) and elf18 (of elongation factor [EF]-Tu), respectively. Here, we reveal that reactive oxygen species spiking and callose deposition are dispensable for the repression of flavonoid accumulation by both pattern recognition receptors. Importantly, FLS2-triggered activation of PATHOGENESIS-RELATED (PR) genes and bacterial basal defenses are enhanced in transparent testa4 plants that are devoid of flavonoids, providing evidence for a functional contribution of flavonoid repression to MTI. Moreover, we identify nine small molecules, of which eight are structurally unrelated, that derepress flavonoid accumulation in the presence of flg22. These compounds allowed us to dissect the FLS2 pathway. Remarkably, one of the identified compounds uncouples flavonoid repression and PR gene activation from the activation of reactive oxygen species, mitogen-activated protein kinases, and callose deposition, corroborating a close link between the former two outputs. Together, our data imply a model in which MAMP-induced repression of flavonoid accumulation serves a role in removing the inherent inhibitory action of flavonoids on an MTI signaling branch. PMID:22080602

  15. Arabidopsis Transcriptome Changes in Response to Phloem-Feeding Silverleaf Whitefly Nymphs. Similarities and Distinctions in Responses to Aphids1[W][OA

    Science.gov (United States)

    Kempema, Louisa A.; Cui, Xinping; Holzer, Frances M.; Walling, Linda L.

    2007-01-01

    Phloem-feeding pests cause extensive crop damage throughout the world, yet little is understood about how plants perceive and defend themselves from these threats. The silverleaf whitefly (SLWF; Bemisia tabaci type B) is a good model for studying phloem-feeding insect-plant interactions, as SLWF nymphs cause little wounding and have a long, continuous interaction with the plant. Using the Affymetrix ATH1 GeneChip to monitor the Arabidopsis (Arabidopsis thaliana) transcriptome, 700 transcripts were found to be up-regulated and 556 down-regulated by SLWF nymphs. Closer examination of the regulation of secondary metabolite (glucosinolate) and defense pathway genes after SLWF-instar feeding shows that responses were qualitatively and quantitatively different from chewing insects and aphids. In addition to the RNA profile distinctions, analysis of SLWF performance on wild-type and phytoalexin-deficient4 (pad4) mutants suggests aphid and SLWF interactions with Arabidopsis were distinct. While pad4-1 mutants were more susceptible to aphids, SLWF development on pad4-1 and wild-type plants was similar. Furthermore, although jasmonic acid genes were repressed and salicylic acid-regulated genes were induced after SLWF feeding, cytological staining of SLWF-infested tissue showed that pathogen defenses, such as localized cell death and hydrogen peroxide accumulation, were not observed. Like aphid and fungal pathogens, callose synthase gene RNAs accumulated and callose deposition was observed in SLWF-infested tissue. These results provide a more comprehensive understanding of phloem-feeding insect-plant interactions and distinguish SLWF global responses. PMID:17189325

  16. Disgenesia do corpo caloso e más-formações associadas: achados de tomografia computadorizada e ressonância magnética Dysgenesis of the corpus callosum and associated malformations: computed tomography and magnetic resonance imaging findings

    Directory of Open Access Journals (Sweden)

    Cristiano Montandon

    2003-10-01

    Full Text Available O termo disgenesia do corpo caloso refere-se a uma má-formação deste com origem na embriogênese do telencéfalo. O relato analisa os achados de tomografia computadorizada e ressonância magnética em 11 pacientes com disgenesia calosa e em um caso de corpo caloso normal com lipoma associado. Esta pode ser distinguida em três grupos: agenesia total (três casos, agenesia parcial (seis casos e hipoplasia (dois casos. Anomalias associadas foram observadas em nove casos, incluindo má-formação de Chiari tipo II (um caso, esquizencefalia (um caso, cisto inter-hemisférico (dois casos, heterotopia nodular (um caso, cisto de Dandy-Walker (um caso e lipoma do corpo caloso (quatro casos. Este artigo demonstra um espectro destes distúrbios, auxiliando na sua interpretação diagnóstica.Callosal dysgenesis is a malformation of the corpus callosum with origins in the embryogenesis of the telencephalon. We reviewed the computed tomography and magnetic resonance imaging findings of 11 patients with callosal dysgenesis and one patient with normal corpus callosum associated with a lipoma. The patients were divided into three distinct groups: total agenesis (three patients, partial agenesis (six patients and hypoplasia (two patients. Associated abnormalities were observed in nine patients, including Chiari II malformation (one patient, schizencephaly (one patient, interhemispheric cyst (two patients, Dandy-Walker cyst (one patient, nodular heterotopy (one patient and lipoma of the corpus callosum (four patients. This paper presents a review that may contribute to the diagnosis of these disorders.

  17. Microstructure of transcallosal motor fibers reflects type of cortical (re-)organization in congenital hemiparesis.

    Science.gov (United States)

    Juenger, Hendrik; Koerte, Inga K; Muehlmann, Marc; Mayinger, Michael; Mall, Volker; Krägeloh-Mann, Ingeborg; Shenton, Martha E; Berweck, Steffen; Staudt, Martin; Heinen, Florian

    2014-11-01

    Early unilateral brain lesions can lead to different types of corticospinal (re-)organization of motor networks. In one group of patients, the contralesional hemisphere exerts motor control not only over the contralateral non-paretic hand but also over the (ipsilateral) paretic hand, as the primary motor cortex is (re-)organized in the contralesional hemisphere. Another group of patients with early unilateral lesions shows "normal" contralateral motor projections starting in the lesioned hemisphere. We investigated how these different patterns of cortical (re-)organization affect interhemispheric transcallosal connectivity in patients with congenital hemiparesis. Eight patients with ipsilateral motor projections (group IPSI) versus 7 patients with contralateral motor projections (group CONTRA) underwent magnetic resonance diffusion tensor imaging (DTI). The corpus callosum (CC) was subdivided in 5 areas (I-V) in the mid-sagittal slice and volumetric information. The following diffusion parameters were calculated: fractional anisotropy (FA), trace, radial diffusivity (RD), and axial diffusivity (AD). DTI revealed significantly lower FA, increased trace and RD for group IPSI compared to group CONTRA in area III of the corpus callosum, where transcallosal motor fibers cross the CC. In the directly neighboring area IV, where transcallosal somatosensory fibers cross the CC, no differences were found for these DTI parameters between IPSI and CONTRA. Volume of callosal subsections showed significant differences for area II (connecting premotor cortices) and III, where group IPSI had lower volume. The results of this study demonstrate that the callosal microstructure in patients with congenital hemiparesis reflects the type of cortical (re-)organization. Early lesions disrupting corticospinal motor projections to the paretic hand consecutively affect the development or maintenance of transcallosal motor fibers. Copyright © 2014 European Paediatric Neurology Society

  18. Characterization of callase (β-1,3-D-glucanase) activity during microsporogenesis in the sterile anthers of Allium sativum L. and the fertile anthers of A. atropurpureum.

    Science.gov (United States)

    Winiarczyk, Krystyna; Jaroszuk-Ściseł, Jolanta; Kupisz, Kamila

    2012-06-01

    We examined callase activity in anthers of sterile Allium sativum (garlic) and fertile Allium atropurpureum. In A. sativum, a species that produces sterile pollen and propagates only vegetatively, callase was extracted from the thick walls of A. sativum microspore tetrads exhibited maximum activity at pH 4.8, and the corresponding in vivo values ranged from 4.5 to 5.0. Once microspores were released, in vitro callase activity peaked at three distinct pH values, reflecting the presence of three callase isoforms. One isoform, which was previously identified in the tetrad stage, displayed maximum activity at pH 4.8, and the remaining two isoforms, which were novel, were most active at pH 6.0 and 7.3. The corresponding in vivo values ranged from pH 4.75 to 6.0. In contrast, in A. atropurpureum, a sexually propagating species, three callase isoforms, active at pH 4.8-5.2, 6.1, and 7.3, were identified in samples of microsporangia that had released their microspores. The corresponding in vivo value for this plant was 5.9. The callose wall persists around A. sativum meiotic cells, whereas only one callase isoform, with an optimum activity of pH 4.8, is active in the acidic environment of the microsporangium. However, this isoform is degraded when the pH rises to 6.0 and two other callase isoforms, maximally active at pH 6.0 and 7.3, appear. Thus, factors that alter the pH of the microsporangium may indirectly affect the male gametophyte development by modulating the activity of callase and thereby regulating the degradation of the callose wall.

  19. Interobserver agreement for diagnostic MRI criteria in suspected multiple sclerosis

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    Barkhof, F.; Waesberghe, J.H.T.M. van [Department of Radiology, Academic Hospital of the Vrije Universiteit, Amsterdam (Netherlands); Filippi, M.; Campi, A. [MS Biosignal Analysis Centre, Department of Neurology, Scientific Institute H San Raffaele, University of Milan (Italy); Miller, D.H. [NMR Research Group, Institute of Neurology, Queen Square, London (United Kingdom); Ader, H.J. [Department of Epidemiology and Biostatistics, Vrije Universiteit, Amsterdam (Netherlands)

    1999-05-01

    MRI is the paraclinical test most widely used to support the diagnosis of multiple sclerosis (MS). We evaluated interobserver agreement in applying diagnostic criteria to MRI obtained at first presentation. Five experienced observers scored 25 sets of images consisting of unenhanced T2- and gadolinium-enhanced T1-weighted images (approximately half the sets were normal). We scored frontal, parietal, temporal, occipital, infratentorial and basal ganglia lesions and the total number of lesions on T2-weighted images; periventricular, callosal, juxtacortical and ovoid lesions and those > 5 mm in maximum diameter; contrast-enhancing and hypointense lesions. Based on a combination of imaging findings patients were classified as compatible or not compatible with MS according to composite criteria. Observer concordance was characterised by weighted kappa values ({kappa}) and mean average difference to the median (MADM) scores. Using the raw scores, there was poor agreement for the total number of lesions on T2-weighted images, and for occipital, oval, juxtacortical and hypointense lesions. Moderate agreement was found for frontal, callosal, basal ganglia and large lesions on T2 weighting. Good agreement was attained for parietal, temporal, infratentorial and periventricular lesions. After dichotomisation according to accepted cut-off values, most criteria performed better, especially the number of lesions on T2-weighted images (P < 0.05). Good agreement was found for the criteria of Paty and Fazekas and moderate agreement for those of Barkhof. While experienced observers may not agree on the total number of lesions, they show quite good agreement for commonly used cut-off points and elements in the composite criteria. This validates the use of MRI in the diagnosis of MS, and the use of dichotomised and composite criteria. (orig.) With 2 tabs., 13 refs.

  20. Characterization of non-host resistance in broad bean to the wheat stripe rust pathogen

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    Cheng Yulin

    2012-06-01

    Full Text Available Abstract Background Non-host resistance (NHR confers plant species immunity against the majority of microbial pathogens and represents the most robust and durable form of plant resistance in nature. As one of the main genera of rust fungi with economic and biological importance, Puccinia infects almost all cereals but is unable to cause diseases on legumes. Little is known about the mechanism of this kind of effective defense in legumes to these non-host pathogens. Results In this study, the basis of NHR in broad bean (Vicia faba L. against the wheat stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst, was characterized. No visible symptoms were observed on broad bean leaves inoculated with Pst. Microscopic observations showed that successful location of stomata and haustoria formation were significantly reduced in Pst infection of broad bean. Attempted infection induced the formation of papillae, cell wall thickening, production of reactive oxygen species, callose deposition and accumulation of phenolic compounds in plant cell walls. The few Pst haustoria that did form in broad bean cells were encased in reactive oxygen and callose materials and those cells elicited cell death. Furthermore, a total of seven defense-related genes were identified and found to be up-regulated during the Pst infection. Conclusions The results indicate that NHR in broad bean against Pst results from a continuum of layered defenses, including basic incompatibility, structural and chemical strengthening of cell wall, posthaustorial hypersensitive response and induction of several defense-related genes, demonstrating the multi-layered feature of NHR. This work also provides useful information for further determination of resistance mechanisms in broad bean to rust fungi, especially the adapted important broad bean rust pathogen, Uromyces viciae-fabae, because of strong similarity and association between NHR of plants to unadapted pathogens and basal

  1. Interhemispheric functional connectivity in anorexia and bulimia nervosa.

    Science.gov (United States)

    Canna, Antonietta; Prinster, Anna; Monteleone, Alessio Maria; Cantone, Elena; Monteleone, Palmiero; Volpe, Umberto; Maj, Mario; Di Salle, Francesco; Esposito, Fabrizio

    2017-05-01

    The functional interplay between hemispheres is fundamental for behavioral, cognitive, and emotional control. Anorexia nervosa (AN) and bulimia nervosa (BN) have been largely studied with brain magnetic resonance imaging (MRI) in relation to the functional mechanisms of high-level processing, but not in terms of possible inter-hemispheric functional connectivity anomalies. Using resting-state functional MRI (fMRI), voxel-mirrored homotopic connectivity (VMHC) and regional inter-hemispheric spectral coherence (IHSC) were studied in 15 AN and 13 BN patients and 16 healthy controls (HC). Using T1-weighted and diffusion tensor imaging MRI scans, regional VMHC values were correlated with the left-right asymmetry of corresponding homotopic gray matter volumes and with the white matter callosal fractional anisotropy (FA). Compared to HC, AN patients exhibited reduced VMHC in cerebellum, insula, and precuneus, while BN patients showed reduced VMHC in dorso-lateral prefrontal and orbito-frontal cortices. The regional IHSC analysis highlighted that the inter-hemispheric functional connectivity was higher in the 'Slow-5' band in all regions except the insula. No group differences in left-right structural asymmetries and in VMHC vs. callosal FA correlations were significant in the comparisons between cohorts. These anomalies, not explained by structural changes, indicate that AN and BN, at least in their acute phase, are associated with a loss of inter-hemispheric connectivity in regions implicated in self-referential, cognitive control and reward processing. These findings may thus gather novel functional markers to explore aberrant features of these eating disorders. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  2. [Neuropsychological approach to visual attention].

    Science.gov (United States)

    Suzuki, Kyoko

    2007-01-01

    Visual experience depends critically on visual attention, which selects a particular aspect of a visual display. Recent clinical, neuroimaging, and animal studies revealed that visual attention was divided into active and passive or top-down and bottom-up attention. Although these dichotomies are clear-cut in definition, visual attention could be modulated by many factors. Detailed observation of brain-injured patients provides with evidence for dynamic and fine control of visual attention. We observed patients with dorsal simultanagnosia and that with callosal disconnection syndrome. Patients with dorsal simultanagnosia demonstrated that extent of visual attention was dynamically changed depending on the level of visual processing. Despite the ability to read a kanji character and to describe its components correctly, a patient could not notice a component that he had just written and could not assemble individual components to make up a correct kanji character. He could point to an overlapping area of two figures. But once he started to color the overlapping area, he missed the margin of the area and colored much larger area. Another patient with dorsal simultanagnosia missed borderlines between columns of a newspaper and read letters continuously across columns. In contrast, he could point to lines between figures or meaningless patterns easily. These findings indicated that visual attention was directed automatically to meaningful characters. A patients with callosal disconnection syndrome demonstrated left unilateral spatial neglect only when he used his right hand to draw figures. Right hand movement, controlled by the left hemisphere, elicited visual attention to the right hemispace, resulting in the left unilateral spatial neglect. Thus visual attention is not simply top-down or bottom up, but is implicitly affected by the visual recognition as well as motor component of the task.

  3. Imposed glutathione-mediated redox switch modulates the tobacco wound-induced protein kinase and salicylic acid-induced protein kinase activation state and impacts on defence against Pseudomonas syringae

    Science.gov (United States)

    Matern, Sanja; Peskan-Berghoefer, Tatjana; Gromes, Roland; Kiesel, Rebecca Vazquez; Rausch, Thomas

    2015-01-01

    The role of the redox-active tripeptide glutathione in plant defence against pathogens has been studied extensively; however, the impact of changes in cellular glutathione redox potential on signalling processes during defence reactions has remained elusive. This study explored the impact of elevated glutathione content on the cytosolic redox potential and on early defence signalling at the level of mitogen-activated protein kinases (MAPKs), as well as on subsequent defence reactions, including changes in salicylic acid (SA) content, pathogenesis-related gene expression, callose depositions, and the hypersensitive response. Wild-type (WT) Nicotiana tabacum L. and transgenic high-glutathione lines (HGL) were transformed with the cytosol-targeted sensor GRX1-roGFP2 to monitor the cytosolic redox state. Surprisingly, HGLs displayed an oxidative shift in their cytosolic redox potential and an activation of the tobacco MAPKs wound-induced protein kinase (WIPK) and SA-induced protein kinase (SIPK). This activation occurred in the absence of any change in free SA content, but was accompanied by constitutively increased expression of several defence genes. Similarly, rapid activation of MAPKs could be induced in WT tobacco by exposure to either reduced or oxidized glutathione. When HGL plants were challenged with adapted or non-adapted Pseudomonas syringae pathovars, the cytosolic redox shift was further amplified and the defence response was markedly increased, showing a priming effect for SA and callose; however, the initial and transient hyperactivation of MAPK signalling was attenuated in HGLs. The results suggest that, in tobacco, MAPK and SA signalling may operate independently, both possibly being modulated by the glutathione redox potential. Possible mechanisms for redox-mediated MAPK activation are discussed. PMID:25628332

  4. Physiological, structural and molecular traits activated in strawberry plants after inoculation with the plant growth-promoting bacterium Azospirillum brasilense REC3.

    Science.gov (United States)

    Guerrero-Molina, M F; Lovaisa, N C; Salazar, S M; Martínez-Zamora, M G; Díaz-Ricci, J C; Pedraza, R O

    2015-05-01

    The plant growth-promoting strain REC3 of Azospirillum brasilense, isolated from strawberry roots, prompts growth promotion and systemic protection against anthracnose disease in this crop. Hence, we hypothesised that A. brasilense REC3 can induce different physiological, structural and molecular responses in strawberry plants. Therefore, the aim of this work was to study these traits activated in Azospirillum-colonised strawberry plants, which have not been assessed until now. Healthy, in vitro micropropagated plants were root-inoculated with REC3 under hydroponic conditions; root and leaf tissues were sampled at different times, and oxidative burst, phenolic compound content, malondialdehyde (MDA) concentration, callose deposition, cell wall fortification and gene expression were evaluated. Azospirillum inoculation enhanced levels of soluble phenolic compounds after 12 h post-inoculation (hpi), while amounts of cell wall bound phenolics were similar in inoculated and control plants. Other early responses activated by REC3 (at 24 hpi) were a decline of lipid peroxidation and up-regulation of strawberry genes involved in defence (FaPR1), bacterial recognition (FaFLS2) and H₂O₂ depuration (FaCAT and FaAPXc). The last may explain the apparent absence of oxidative burst in leaves after bacterial inoculation. Also, REC3 inoculation induced delayed structural responses such as callose deposition and cell wall fortification (at 72 hpi). Results showed that A. brasilense REC3 is capable of exerting beneficial effects on strawberry plants, reinforcing their physiological and cellular characteristics, which in turns contribute to improve plant performance. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  5. Importance of correctly interpreting magnetic resonance imaging to diagnose posterior reversible encephalopathy syndrome associated with HELLP syndrome: a case report.

    Science.gov (United States)

    Tetsuka, Syuichi; Nonaka, Hiroaki

    2017-05-25

    Severe haemolysis, elevated liver enzyme levels, and low platelet count (HELLP) syndrome in pregnancy are possible underlying trigger factors for posterior reversible encephalopathy syndrome (PRES). Magnetic resonance imaging (MRI) shows diffuse signal abnormalities involving the subcortical white matter in the parieto-occipital lobes. Although the diagnosis of RPES was clearly established by the distinctive reversibility of clinical and radiological abnormalities, it is difficult to distinguish from differential diagnosis. Thus, it is important to correctly interpret MRI. We describe a case of HELLP syndrome with PRES. A 38-year-old pregnant woman was admitted to our hospital as an emergency case with a complaint of upper abdominal pain and headache at 29 weeks of pregnancy and the development of HELLP syndrome. An emergency caesarean section was immediately performed. After the operation, the patient received intravenous corticosteroids, and her blood pressure was controlled. Thereafter, she showed an altered mental status. MRI showed hypersignal intense lesions in the cortical and subcortical white matter in the occipital lobes, basal ganglia and callosal splenium in both the fluid-attenuated inversion recovery (FLAIR) sequence and apparent diffusion coefficient (ADC), but these lesions were not recognized in diffusion-weighted imaging (DWI). These images were suggestive of PRES. The patient was kept in the hospital and received the appropriate treatment, after which the patient's level of consciousness improved and all laboratory tests and imaging examinations returned normal. The MRI findings were useful for the prompt diagnosis of PRES, characterized by hypersignals in FLAIR and ADC, but not in DWI. Additionally, there was an "atypical" MRI appearance of basal ganglial and callosal splenial involvement in this case, which may mistakenly lead clinicians to diagnose other aetiologies than typical PRES. It is considered that vasogenic oedema is the main

  6. Comparative Transcriptome and iTRAQ Proteome Analyses of Citrus Root Responses to Candidatus Liberibacter asiaticus Infection

    Science.gov (United States)

    Jiang, Nong-hui; Jiang, Bo; Zhang, Yong-yan; Wu, Bo; Hu, Min-lun; Zeng, Ji-wu; Yan, Hua-xue; Yi, Gan-jun; Zhong, Guang-yan

    2015-01-01

    Root samples of ‘Sanhu’ red tangerine trees infected with and without Candidatus Liberibacter asiaticus (CLas) were collected at 50 days post inoculation and subjected to RNA-sequencing and isobaric tags for relative and absolute quantification (iTRAQ) to profile the differentially expressed genes (DEGs) and proteins (DEPs), respectively. Quantitative real-time PCR was subsequently used to confirm the expression of 16 selected DEGs. Results showed that a total of 3956 genes and 78 proteins were differentially regulated by HLB-infection. Among the most highly up-regulated DEPs were sperm specific protein 411, copper ion binding protein, germin-like proteins, subtilisin-like proteins and serine carboxypeptidase-like 40 proteins whose transcript levels were concomitantly up-regulated as shown by RNA-seq data. Comparison between our results and those of the previously reported showed that known HLB-modulated biological pathways including cell-wall modification, protease-involved protein degradation, carbohydrate metabolism, hormone synthesis and signaling, transcription activities, and stress responses were similarly regulated by HLB infection but different or root-specific changes did exist. The root unique changes included the down-regulation in genes of ubiquitin-dependent protein degradation pathway, secondary metabolism, cytochrome P450s, UDP-glucosyl transferases and pentatricopeptide repeat containing proteins. Notably, nutrient absorption was impaired by HLB-infection as the expression of the genes involved in Fe, Zn, N and P adsorption and transportation were significantly changed. HLB-infection induced some cellular defense responses but simultaneously reduced the biosynthesis of the three major classes of secondary metabolites, many of which are known to have anti-pathogen activities. Genes involved in callose deposition were up-regulated whereas those involved in callose degradation were also up-regulated, indicating that the sieve tube elements in

  7. Comparative Transcriptome and iTRAQ Proteome Analyses of Citrus Root Responses to Candidatus Liberibacter asiaticus Infection.

    Science.gov (United States)

    Zhong, Yun; Cheng, Chun-Zhen; Jiang, Nong-Hui; Jiang, Bo; Zhang, Yong-Yan; Wu, Bo; Hu, Min-Lun; Zeng, Ji-Wu; Yan, Hua-Xue; Yi, Gan-Jun; Zhong, Guang-Yan

    2015-01-01

    Root samples of 'Sanhu' red tangerine trees infected with and without Candidatus Liberibacter asiaticus (CLas) were collected at 50 days post inoculation and subjected to RNA-sequencing and isobaric tags for relative and absolute quantification (iTRAQ) to profile the differentially expressed genes (DEGs) and proteins (DEPs), respectively. Quantitative real-time PCR was subsequently used to confirm the expression of 16 selected DEGs. Results showed that a total of 3956 genes and 78 proteins were differentially regulated by HLB-infection. Among the most highly up-regulated DEPs were sperm specific protein 411, copper ion binding protein, germin-like proteins, subtilisin-like proteins and serine carboxypeptidase-like 40 proteins whose transcript levels were concomitantly up-regulated as shown by RNA-seq data. Comparison between our results and those of the previously reported showed that known HLB-modulated biological pathways including cell-wall modification, protease-involved protein degradation, carbohydrate metabolism, hormone synthesis and signaling, transcription activities, and stress responses were similarly regulated by HLB infection but different or root-specific changes did exist. The root unique changes included the down-regulation in genes of ubiquitin-dependent protein degradation pathway, secondary metabolism, cytochrome P450s, UDP-glucosyl transferases and pentatricopeptide repeat containing proteins. Notably, nutrient absorption was impaired by HLB-infection as the expression of the genes involved in Fe, Zn, N and P adsorption and transportation were significantly changed. HLB-infection induced some cellular defense responses but simultaneously reduced the biosynthesis of the three major classes of secondary metabolites, many of which are known to have anti-pathogen activities. Genes involved in callose deposition were up-regulated whereas those involved in callose degradation were also up-regulated, indicating that the sieve tube elements in roots

  8. Apoplastic peroxidases are required for salicylic acid-mediated defense against Pseudomonas syringae.

    Science.gov (United States)

    Mammarella, Nicole D; Cheng, Zhenyu; Fu, Zheng Qing; Daudi, Arsalan; Bolwell, G Paul; Dong, Xinnian; Ausubel, Frederick M

    2015-04-01

    Reactive oxygen species (ROS) generated by NADPH oxidases or apoplastic peroxidases play an important role in the plant defense response. Diminished expression of at least two Arabidopsis thaliana peroxidase encoding genes, PRX33 (At3g49110) and PRX34 (At3g49120), as a consequence of anti-sense expression of a heterologous French bean peroxidase gene (asFBP1.1), were previously shown to result in reduced levels of ROS following pathogen attack, enhanced susceptibility to a variety of bacterial and fungal pathogens, and reduced levels of callose production and defense-related gene expression in response to the microbe associated molecular pattern (MAMP) molecules flg22 and elf26. These data demonstrated that the peroxidase-dependent oxidative burst plays an important role in the elicitation of pattern-triggered immunity (PTI). Further work reported in this paper, however, shows that asFBP1.1 antisense plants are not impaired in all PTI-associated responses. For example, some but not all flg22-elicited genes are induced to lower levels by flg22 in asFPB1.1, and callose deposition in asFPB1.1 is similar to wild-type following infiltration with a Pseudomonas syringae hrcC mutant or with non-host P. syringae pathovars. Moreover, asFPB1.1 plants did not exhibit any apparent defect in their ability to mount a hypersensitive response (HR). On the other hand, salicylic acid (SA)-mediated activation of PR1 was dramatically impaired in asFPB1.1 plants. In addition, P. syringae-elicited expression of many genes known to be SA-dependent was significantly reduced in asFBP1.1 plants. Consistent with this latter result, in asFBP1.1 plants the key regulator of SA-mediated responses, NPR1, showed both dramatically decreased total protein abundance and a failure to monomerize, which is required for its translocation into the nucleus. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Physiological and molecular analysis on root growth associated with the tolerance to aluminum and drought individual and combined in Tibetan wild and cultivated barley.

    Science.gov (United States)

    Ahmed, Imrul Mosaddek; Nadira, Umme Aktari; Cao, Fangbin; He, Xiaoyan; Zhang, Guoping; Wu, Feibo

    2016-04-01

    The drought-stimulated gene expression of NCED, SUS, and KS - DHN and ABA signal cross-talk with other phytohormones maintains barley root growth under drought stress at pH 4.0 plus polyethylene glycol plus aluminum. Aluminum (Al) toxicity and drought are two major factors that limit barley production. In this work, the individual and combined effects of Al/acid and polyethylene glycol (PEG 6000) induced drought stress that suppressed root growth and caused oxidative damage as characterized by increased H2O2 and O2(.-) accumulation. The wild-barley genotypes, XZ5 and XZ29, exhibited a higher tolerance than the two cultivars Dayton (Al tolerant) and Tadmor (drought tolerant) under combined stress (pH 4.0 + PEG + Al). The oxidative damage induced by PEG was more severe at pH 4.0 than at pH 6.0. In XZ29, the highest root secretion of malate and citrate was recorded, and the least Al uptake in the four genotypes. In XZ5, a peak accumulation of ABA and minor synthesis of zeatin riboside and ethylene were found being essential in maintaining primary root elongation and root hair development. PEG-induced drought stress repressed Al uptake in root tips, with a lower increase in callose formation and HvMATE (Hordeum vulgare multidrug and toxic compound exudation) expression compared to Al-induced callose production. Stress by pH 4.0 + PEG + Al up-regulated 9-cis-epoxycarotenoid dioxygenase (NCED) which is involved in ABA biosynthesis. Such treatment stimulated the regulation of ABA-dependent genes sucrose synthase (SUS) and KS-type dehydrin (KS-DHN) in root tips. Our results suggest that the tolerance ranking to pH 4.0 + PEG + Al stress in Tibetan wild barley by gene expression is closely correlated to physiological indices. The results show that acclimatisation to pH 4.0 + PEG + Al stress involves specific responses in XZ5 and XZ29. The present study provides insights into the effects of Al/acid and drought combined stress on the abundance of physiological indices in the

  10. Risk factors for subclinical intramammary infection in dairy goats in two longitudinal field studies evaluated by Bayesian logistic regression.

    Science.gov (United States)

    Koop, Gerrit; Collar, Carol A; Toft, Nils; Nielen, Mirjam; van Werven, Tine; Bacon, Debora; Gardner, Ian A

    2013-03-01

    Identification of risk factors for subclinical intramammary infections (IMI) in dairy goats should contribute to improved udder health. Intramammary infection may be diagnosed by bacteriological culture or by somatic cell count (SCC) of a milk sample. Both bacteriological culture and SCC are imperfect tests, particularly lacking sensitivity, which leads to misclassification and thus to biased estimates of odds ratios in risk factor studies. The objective of this study was to evaluate risk factors for the true (latent) IMI status of major pathogens in dairy goats. We used Bayesian logistic regression models that accounted for imperfect measurement of IMI by both culture and SCC. Udder half milk samples were collected from 530 Dutch and 438 California dairy goats in 10 herds on 3 occasions during lactation. Udder halves were classified as positive or negative for isolation of a major pathogen (mostly Staphylococcus aureus) on bacteriological culture and as positive or negative for SCC (cut-off of 2000 × 10(3)cells/mL). Potentially controllable risk factors (udder conformation, teat size, teat shape, teat placement, teat-end shape, teat-end callosity thickness, teat-end callosity roughness, caprine arthritis encephalitis-virus infection status, and kidding season), and uncontrollable risk factors (parity, lactation stage, milk yield, pregnancy status, and breed) were measured in the Dutch study, the Californian study or in both studies. Bayesian logistic regression models were constructed in which the true (but latent) infection status was linked to the joint test results, as functions of test sensitivity and specificity. The latent IMI status was the dependent variable in the logistic regression model with risk factors as independent variables and with random herd and goat effects. For the combined data from both studies, the culture-based estimate of apparent prevalence of major pathogens in udder halves was 2.6% (137/5220) and the estimate of the apparent

  11. Occupational dermatoses among cottage industry workers of Kashmir Valley in North India

    Directory of Open Access Journals (Sweden)

    Saniya Akhtar

    2017-01-01

    Full Text Available Introduction: Cottage industry is usually a small-scale industry operated from home by family members using their own equipment. Kashmir has a unique cottage industry of its own which deals with production of many handicrafts, which may lead to a peculiar pattern of skin diseases in these artisans. Aim: The aim of this study was to find out the pattern of skin disorders in the cottage industry workers of Kashmir valley, with primary focus on the occupation-related dermatoses and to identify the most common cutaneous manifestation in these workers. Materials and Methods: This was a cross-sectional descriptive study in which 1062 cottage industry workers engaged in different crafts were screened. A detailed history taking and examination was carried out in each worker and the diagnosis was made on clinical grounds. Wherever deemed necessary, relevant investigations were done to establish the nature of the disease. Results: A total of 1062 workers were evaluated for the presence of skin disorders. The male-to-female ratio was 1:1.5. The mean age of the study group was 30.3 years ± 10.79 years, with maximum number of workers (164 belonging to the crewel embroidery industry. The mean duration of work was 6.4 ± 2.08 hours/day. A total of 953 workers (89.7% had cutaneous manifestations, with callosities being the most common finding seen in 371 workers (35%, followed by cumulative insult dermatitis seen in 201 workers (19%. Conclusion: Cottage industry of Kashmir valley is a unique occupational group where a high percentage of workers had cutaneous manifestations related to their occupation, with callosities being the most common finding. Information and better knowledge regarding these dermatoses are important in devising strategies to improve the health scenario of these workers. Simple measures such as proper use of instruments, use of protective gloves, guarded use of chemicals, and hand washing may be very beneficial in reducing the burden of

  12. Patterns of functional enzyme activity in fungus farming ambrosia beetles

    Directory of Open Access Journals (Sweden)

    De Fine Licht Henrik H

    2012-06-01

    Full Text Available Abstract Introduction In wood-dwelling fungus-farming weevils, the so-called ambrosia beetles (Curculionidae: Scolytinae and Platypodinae, wood in the excavated tunnels is used as a medium for cultivating fungi by the combined action of digging larvae (which create more space for the fungi to grow and of adults sowing and pruning the fungus. The beetles are obligately dependent on the fungus that provides essential vitamins, amino acids and sterols. However, to what extent microbial enzymes support fungus farming in ambrosia beetles is unknown. Here we measure (i 13 plant cell-wall degrading enzymes in the fungus garden microbial consortium of the ambrosia beetle Xyleborinus saxesenii, including its primary fungal symbionts, in three compartments of laboratory maintained nests, at different time points after gallery foundation and (ii four specific enzymes that may be either insect or microbially derived in X. saxesenii adult and larval individuals. Results We discovered that the activity of cellulases in ambrosia fungus gardens is relatively small compared to the activities of other cellulolytic enzymes. Enzyme activity in all compartments of the garden was mainly directed towards hemicellulose carbohydrates such as xylan, glucomannan and callose. Hemicellulolytic enzyme activity within the brood chamber increased with gallery age, whereas irrespective of the age of the gallery, the highest overall enzyme activity were detected in the gallery dump material expelled by the beetles. Interestingly endo-β-1,3(4-glucanase activity capable of callose degradation was identified in whole-body extracts of both larvae and adult X. saxesenii, whereas endo-β-1,4-xylanase activity was exclusively detected in larvae. Conclusion Similar to closely related fungi associated with bark beetles in phloem, the microbial symbionts of ambrosia beetles hardly degrade cellulose. Instead, their enzyme activity is directed mainly towards comparatively more easily

  13. The brain in myotonic dystrophy 1 and 2: evidence for a predominant white matter disease.

    Science.gov (United States)

    Minnerop, Martina; Weber, Bernd; Schoene-Bake, Jan-Christoph; Roeske, Sandra; Mirbach, Sandra; Anspach, Christian; Schneider-Gold, Christiane; Betz, Regina C; Helmstaedter, Christoph; Tittgemeyer, Marc; Klockgether, Thomas; Kornblum, Cornelia

    2011-12-01

    Myotonic dystrophy types 1 and 2 are progressive multisystemic disorders with potential brain involvement. We compared 22 myotonic dystrophy type 1 and 22 myotonic dystrophy type 2 clinically and neuropsychologically well-characterized patients and a corresponding healthy control group using structural brain magnetic resonance imaging at 3 T (T(1)/T(2)/diffusion-weighted). Voxel-based morphometry and diffusion tensor imaging with tract-based spatial statistics were applied for voxel-wise analysis of cerebral grey and white matter affection (P(corrected) brain changes with clinical and neuropsychological data. White matter lesions rated visually were more prevalent and severe in myotonic dystrophy type 1 compared with controls, with frontal white matter most prominently affected in both disorders, and temporal lesions restricted to myotonic dystrophy type 1. Voxel-based morphometry analyses demonstrated extensive white matter involvement in all cerebral lobes, brainstem and corpus callosum in myotonic dystrophy types 1 and 2, while grey matter decrease (cortical areas, thalamus, putamen) was restricted to myotonic dystrophy type 1. Accordingly, we found more prominent white matter affection in myotonic dystrophy type 1 than myotonic dystrophy type 2 by diffusion tensor imaging. Association fibres throughout the whole brain, limbic system fibre tracts, the callosal body and projection fibres (e.g. internal/external capsules) were affected in myotonic dystrophy types 1 and 2. Central motor pathways were exclusively impaired in myotonic dystrophy type 1. We found mild executive and attentional deficits in our patients when neuropsychological tests were corrected for manual motor dysfunctioning. Regression analyses revealed associations of white matter affection with several clinical parameters in both disease entities, but not with neuropsychological performance. We showed that depressed mood and fatigue were more prominent in patients with myotonic dystrophy type 1

  14. Patterns of functional enzyme activity in fungus farming ambrosia beetles

    Science.gov (United States)

    2012-01-01

    Introduction In wood-dwelling fungus-farming weevils, the so-called ambrosia beetles (Curculionidae: Scolytinae and Platypodinae), wood in the excavated tunnels is used as a medium for cultivating fungi by the combined action of digging larvae (which create more space for the fungi to grow) and of adults sowing and pruning the fungus. The beetles are obligately dependent on the fungus that provides essential vitamins, amino acids and sterols. However, to what extent microbial enzymes support fungus farming in ambrosia beetles is unknown. Here we measure (i) 13 plant cell-wall degrading enzymes in the fungus garden microbial consortium of the ambrosia beetle Xyleborinus saxesenii, including its primary fungal symbionts, in three compartments of laboratory maintained nests, at different time points after gallery foundation and (ii) four specific enzymes that may be either insect or microbially derived in X. saxesenii adult and larval individuals. Results We discovered that the activity of cellulases in ambrosia fungus gardens is relatively small compared to the activities of other cellulolytic enzymes. Enzyme activity in all compartments of the garden was mainly directed towards hemicellulose carbohydrates such as xylan, glucomannan and callose. Hemicellulolytic enzyme activity within the brood chamber increased with gallery age, whereas irrespective of the age of the gallery, the highest overall enzyme activity were detected in the gallery dump material expelled by the beetles. Interestingly endo-β-1,3(4)-glucanase activity capable of callose degradation was identified in whole-body extracts of both larvae and adult X. saxesenii, whereas endo-β-1,4-xylanase activity was exclusively detected in larvae. Conclusion Similar to closely related fungi associated with bark beetles in phloem, the microbial symbionts of ambrosia beetles hardly degrade cellulose. Instead, their enzyme activity is directed mainly towards comparatively more easily accessible hemicellulose

  15. Msp40 effector of root-knot nematode manipulates plant immunity to facilitate parasitism.

    Science.gov (United States)

    Niu, Junhai; Liu, Pei; Liu, Qian; Chen, Changlong; Guo, Quanxin; Yin, Junmei; Yang, Guangsui; Jian, Heng

    2016-01-22

    Root-knot nematodes (RKNs) are obligate biotrophic parasites that invade plant roots and engage in prolonged and intimate relationships with their hosts. Nematode secretions, some of which have immunosuppressing activity, play essential roles in successful parasitism; however, their mechanisms of action remain largely unknown. Here, we show that the RKN-specific gene MiMsp40, cloned from Meloidogyne incognita, is expressed exclusively in subventral oesophageal gland cells and is strongly upregulated during early parasitic stages. Arabidopsis plants overexpressing MiMsp40 were more susceptible to nematode infection than were wild type plants. Conversely, the host-derived MiMsp40 RNAi suppressed nematode parasitism and/or reproduction. Moreover, overexpression of MiMsp40 in plants suppressed the deposition of callose and the expression of marker genes for bacterial elicitor elf18-triggered immunity. Transient expression of MiMsp40 prevented Bax-triggered defence-related programmed cell death. Co-agroinfiltration assays indicated that MiMsp40 also suppressed macroscopic cell death triggered by MAPK cascades or by the ETI cognate elicitors R3a/Avr3a. Together, these results demonstrate that MiMsp40 is a novel Meloidogyne-specific effector that is injected into plant cells by early parasitic stages of the nematode and that plays a role in suppressing PTI and/or ETI signals to facilitate RKN parasitism.

  16. Visualizing the neural bases of a disconnection syndrome with diffusion tensor imaging.

    Science.gov (United States)

    Molko, N; Cohen, L; Mangin, J F; Chochon, F; Lehéricy, S; Le Bihan, D; Dehaene, S

    2002-05-15

    Disconnection syndromes are often conceptualized exclusively within cognitive box-and-arrow diagrams unrelated to brain anatomy. In a patient with alexia in his left visual field resulting from a posterior callosal lesion, we illustrate how diffusion tensor imaging can reveal the anatomical bases of a disconnection syndrome by tracking the degeneration of neural pathways and relating it to impaired fMRI activations and behavior. Compared to controls, an abnormal pattern of brain activity was observed in the patient during word reading, with a lack of activation of the left visual word form area (VWFA) by left hemifield words. Statistical analyses of diffusion images revealed a damaged fiber tract linking the left ventral occipito-temporal region to its right homolog across the lesioned area of corpus callosum and stopping close to the areas found active in fMRI. The behavioral disconnection syndrome could, thus, be related functionally to abnormal fMRI activations and anatomically to the absence of a connection between those activations. The present approach, based on the "negative tracking" of degenerated bundles, provides new perspectives on the understanding of human brain connections and disconnections.

  17. Cognitive-motor dysfunction after severe traumatic brain injury: A cerebral interhemispheric disconnection syndrome.

    Science.gov (United States)

    Falchook, Adam D; Porges, Eric C; Nadeau, Stephen E; Leon, Susan A; Williamson, John B; Heilman, Kenneth M

    2015-01-01

    In most right-handed people, the left hemisphere is dominant for programming the temporal and spatial "how" (praxis) aspects of purposeful skilled movements, and the right hemisphere is dominant for control of the intentional "when" aspects of actions that mediate initiation, persistence, termination, and inhibition. Since the interhemispheric axons of the corpus callosum are especially susceptible to shearing from torsional forces during traumatic brain injury (TBI), the goal of this study was to learn whether participants with a history of severe traumatic brain injury demonstrate three types of cognitive-motor impairments that may result from callosal injury: ideomotor apraxia of the left hand, limb kinetic apraxia of the left hand, and hypokinesia of the right hand in response to left hemispatial stimuli. Nine participants with severe TBI and nine healthy control participants were studied for the presence of ideomotor apraxia, limb kinetic apraxia, and hypokinesia. When compared to the control participants, the participants with TBI revealed ideomotor apraxia and limb kinetic apraxia of the left hand and hypokinesia in response to left-sided visual stimuli when tested with the right hand. TBI appears to cause unilateral disorders of cognitive-motor functions. Future research is needed to understand how these cognitive-motor disorders are related to interhemispheric disconnection most likely induced by injury to the corpus callosum.

  18. N-Acyl-Homoserine Lactone Primes Plants for Cell Wall Reinforcement and Induces Resistance to Bacterial Pathogens via the Salicylic Acid/Oxylipin Pathway.

    Science.gov (United States)

    Schenk, Sebastian T; Hernández-Reyes, Casandra; Samans, Birgit; Stein, Elke; Neumann, Christina; Schikora, Marek; Reichelt, Michael; Mithöfer, Axel; Becker, Annette; Kogel, Karl-Heinz; Schikora, Adam

    2014-06-01

    The ability of plants to monitor their surroundings, for instance the perception of bacteria, is of crucial importance. The perception of microorganism-derived molecules and their effector proteins is the best understood of these monitoring processes. In addition, plants perceive bacterial quorum sensing (QS) molecules used for cell-to-cell communication between bacteria. Here, we propose a mechanism for how N-acyl-homoserine lactones (AHLs), a group of QS molecules, influence host defense and fortify resistance in Arabidopsis thaliana against bacterial pathogens. N-3-oxo-tetradecanoyl-l-homoserine lactone (oxo-C14-HSL) primed plants for enhanced callose deposition, accumulation of phenolic compounds, and lignification of cell walls. Moreover, increased levels of oxylipins and salicylic acid favored closure of stomata in response to Pseudomonas syringae infection. The AHL-induced resistance seems to differ from the systemic acquired and the induced systemic resistances, providing new insight into inter-kingdom communication. Consistent with the observation that short-chain AHLs, unlike oxo-C14-HSL, promote plant growth, treatments with C6-HSL, oxo-C10-HSL, or oxo-C14-HSL resulted in different transcriptional profiles in Arabidopsis. Understanding the priming induced by bacterial QS molecules augments our knowledge of plant reactions to bacteria and suggests strategies for using beneficial bacteria in plant protection. © 2014 American Society of Plant Biologists. All rights reserved.

  19. N-Acyl-Homoserine Lactone Primes Plants for Cell Wall Reinforcement and Induces Resistance to Bacterial Pathogens via the Salicylic Acid/Oxylipin Pathway[C][W][OPEN

    Science.gov (United States)

    Schenk, Sebastian T.; Hernández-Reyes, Casandra; Samans, Birgit; Stein, Elke; Neumann, Christina; Schikora, Marek; Reichelt, Michael; Mithöfer, Axel; Becker, Annette; Kogel, Karl-Heinz; Schikora, Adam

    2014-01-01

    The ability of plants to monitor their surroundings, for instance the perception of bacteria, is of crucial importance. The perception of microorganism-derived molecules and their effector proteins is the best understood of these monitoring processes. In addition, plants perceive bacterial quorum sensing (QS) molecules used for cell-to-cell communication between bacteria. Here, we propose a mechanism for how N-acyl-homoserine lactones (AHLs), a group of QS molecules, influence host defense and fortify resistance in Arabidopsis thaliana against bacterial pathogens. N-3-oxo-tetradecanoyl-l-homoserine lactone (oxo-C14-HSL) primed plants for enhanced callose deposition, accumulation of phenolic compounds, and lignification of cell walls. Moreover, increased levels of oxylipins and salicylic acid favored closure of stomata in response to Pseudomonas syringae infection. The AHL-induced resistance seems to differ from the systemic acquired and the induced systemic resistances, providing new insight into inter-kingdom communication. Consistent with the observation that short-chain AHLs, unlike oxo-C14-HSL, promote plant growth, treatments with C6-HSL, oxo-C10-HSL, or oxo-C14-HSL resulted in different transcriptional profiles in Arabidopsis. Understanding the priming induced by bacterial QS molecules augments our knowledge of plant reactions to bacteria and suggests strategies for using beneficial bacteria in plant protection. PMID:24963057

  20. Wounding in the plant tissue: the defense of a dangerous passage

    Directory of Open Access Journals (Sweden)

    Daniel Valentin Savatin

    2014-09-01

    Full Text Available Plants are continuously exposed to agents such as herbivores and environmental mechanical stresses that cause wounding and open the way to the invasion by microbial pathogens. Wounding provides nutrients to pathogens and facilitates their entry into the tissue and subsequent infection. Plants have evolved constitutive and induced defense mechanisms to properly respond to wounding and prevent infection. The constitutive defenses are represented by physical barriers, i.e. the presence of cuticle or lignin, or by metabolites that act as toxins or deterrents for herbivores. Plants are also able to sense the injured tissue as an altered self and induce responses similar to those activated by pathogen infection. Endogenous molecules released from wounded tissue may act as Damage-Associated Molecular Patterns (DAMPs that activate the plant innate immunity. Wound-induced responses are both rapid, such as the oxidative burst and the expression of defense-related genes, and late, such as the callose deposition, the accumulation of proteinase inhibitors and of hydrolytic enzymes (i.e. chitinases and gluganases. Typical examples of DAMPs involved in the response to wounding are the peptide systemin and the oligogalacturonides, which are oligosaccharides released from the pectic component of the cell wall. Responses to wounding take place both at the site of damage (local response and systemically (systemic response and are mediated by hormones such as jasmonic acid, ethylene, salicylic acid and abscisic acid.

  1. Proteomic analysis of grapevine resistance induced by Trichoderma harzianum T39 reveals specific defence pathways activated against downy mildew

    Science.gov (United States)

    Perazzolli, Michele

    2012-01-01

    Downy mildew is caused by the oomycete Plasmopara viticola and is one of the most serious diseases of grapevine. The beneficial microorganism Trichoderma harzianum T39 (T39) has previously been shown to induce plant-mediated resistance and to reduce the severity of downy mildew in susceptible grapevines. In order to better understand the cellular processes associated with T39-induced resistance, the proteomic and histochemical changes activated by T39 in grapevine were investigated before and 1 day after P. viticola inoculation. A comprehensive proteomic analysis of T39-induced resistance in grapevine was performed using an eight-plex iTRAQ protocol, resulting in the identification and quantification of a total of 800 proteins. Most of the proteins directly affected by T39 were found to be involved in signal transduction, indicating activation of a complete microbial recognition machinery. Moreover, T39-induced resistance was associated with rapid accumulation of reactive oxygen species and callose at infection sites, as well as changes in abundance of proteins involved in response to stress and redox balance, indicating an active defence response to downy mildew. On the other hand, proteins affected by P. viticola in control plants mainly decreased in abundance, possibly reflecting the establishment of a compatible interaction. Finally, the high-throughput iTRAQ protocol allowed de novo peptide sequencing, which will be used to improve annotation of the Vitis vinifera cv. Pinot Noir proteome. PMID:23105132

  2. Discovery of ADP-ribosylation and other plant defense pathway elements through expression profiling of four different Arabidopsis-Pseudomonas R-avr interactions.

    Science.gov (United States)

    Adams-Phillips, Lori; Wan, Jinrong; Tan, Xiaoping; Dunning, F Mark; Meyers, Blake C; Michelmore, Richard W; Bent, Andrew F

    2008-05-01

    A dissection of plant defense pathways was initiated through gene expression profiling of the responses of a single Arabidopsis thaliana genotype to isogenic Pseudomonas syringae strains expressing one of four different cloned avirulence (avr) genes. Differences in the expression profiles elicited by different resistance (R)-avr interactions were observed. A role for poly(ADP-ribosyl)ation in plant defense responses was suggested initially by the upregulated expression of genes encoding NUDT7 and poly(ADP-ribose) glycohydrolase in multiple R-avr interactions. Gene knockout plant lines were tested for 20 candidate genes identified by the expression profiling, and Arabidopsis NUDT7 mutants allowed less growth of virulent P. syringae (as previously reported) but also exhibited a reduced hypersensitive-response phenotype. Inhibitors of poly(ADP-ribose) polymerase (PARP) disrupted FLS2-mediated basal defense responses such as callose deposition. EIN2 (ethylene response) and IXR1 and IXR2 (cellulose synthase) mutants impacted the FLS2-mediated responses that occur during PARP inhibition, whereas no impacts were observed for NPR1, PAD4, or NDR1 mutants. In the expression profiling work, false-positive selection and grouping of genes was reduced by requiring simultaneous satisfaction of statistical significance criteria for each of three separate analysis methods, and by clustering genes based on statistical confidence values for each gene rather than on average fold-change of transcript abundance.

  3. Natural variation in maize aphid resistance is associated with 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one glucoside methyltransferase activity.

    Science.gov (United States)

    Meihls, Lisa N; Handrick, Vinzenz; Glauser, Gaetan; Barbier, Hugues; Kaur, Harleen; Haribal, Meena M; Lipka, Alexander E; Gershenzon, Jonathan; Buckler, Edward S; Erb, Matthias; Köllner, Tobias G; Jander, Georg

    2013-06-01

    Plants differ greatly in their susceptibility to insect herbivory, suggesting both local adaptation and resistance tradeoffs. We used maize (Zea mays) recombinant inbred lines to map a quantitative trait locus (QTL) for the maize leaf aphid (Rhopalosiphum maidis) susceptibility to maize Chromosome 1. Phytochemical analysis revealed that the same locus was also associated with high levels of 2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one glucoside (HDMBOA-Glc) and low levels of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one glucoside (DIMBOA-Glc). In vitro enzyme assays with candidate genes from the region of the QTL identified three O-methyltransferases (Bx10a-c) that convert DIMBOA-Glc to HDMBOA-Glc. Variation in HDMBOA-Glc production was attributed to a natural CACTA family transposon insertion that inactivates Bx10c in maize lines with low HDMBOA-Glc accumulation. When tested with a population of 26 diverse maize inbred lines, R. maidis produced more progeny on those with high HDMBOA-Glc and low DIMBOA-Glc. Although HDMBOA-Glc was more toxic to R. maidis than DIMBOA-Glc in vitro, BX10c activity and the resulting decline of DIMBOA-Glc upon methylation to HDMBOA-Glc were associated with reduced callose deposition as an aphid defense response in vivo. Thus, a natural transposon insertion appears to mediate an ecologically relevant trade-off between the direct toxicity and defense-inducing properties of maize benzoxazinoids.

  4. Mapping pachytene chromosomes of coffee using a modified protocol for fluorescence in situ hybridization

    Science.gov (United States)

    Iacia, Ana Amélia Sanchez; Pinto-Maglio, Cecília A. F.

    2013-01-01

    Fluorescence in situ hybridization (FISH) is the most direct method for physically mapping DNA sequences on chromosomes. Fluorescence in situ hybridization mapping of meiotic chromosomes during the pachytene stage is an important tool in plant cytogenetics, because it provides high-resolution measurements of physical distances. Fluorescence in situ hybridization mapping of coffee pachytene chromosomes offers significant advantages compared with FISH mapping of somatic chromosomes, because pachytene chromosomes are 30 times longer and provide additional cytological markers. However, the application of this technique to pachytene chromosomes has been complicated by problems in making preparations of meiotic chromosomes and by difficulties in the application of standard FISH protocols. We have been able to overcome most of these obstacles in applying the FISH technique to the pachytene chromosomes of coffee plants. Digesting the external callose layer surrounding the pollen mother cells (PMCs) in conjunction with other procedures permitted suitable pachytene chromosomes to be obtained by increasing cell permeability, which allowed the probe sequences to enter the cells. For the first time, hybridization signals were registered on coffee pachytene chromosomes using the FISH technique with a repetitive sequence as a probe. We obtained slides on which 80 % of the PMCs had hybridization signals, resulting in FISH labelling with high efficiency. The procedure does not seem to be dependent on the genotype, because hybridization signals were detected in genetically different coffee plants. These findings enhance the possibilities for high-resolution physical mapping of coffee chromosomes. PMID:24244840

  5. Corpus callosum involvement: a useful clue for differentiating Fabry disease from multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Cocozza, Sirio; Olivo, Gaia; Pontillo, Giuseppe; Ugga, Lorenzo; De Rosa, Dario; Imbriaco, Massimo; Brunetti, Arturo; Tedeschi, Enrico [University ' ' Federico II' ' , Department of Advanced Biomedical Sciences, Naples (Italy); Riccio, Eleonora; Migliaccio, Silvia; Pisani, Antonio [University ' ' Federico II' ' , Department of Public Health, Nephrology Unit, Naples (Italy); Russo, Camilla [University ' ' Federico II' ' , Department of Advanced Biomedical Sciences, Naples (Italy); Feriozzi, Sandro [Belcolle Hospital, Nephrology and Dialysis Department, Viterbo (Italy); Veroux, Massimiliano [University Hospital of Catania, Department of Medical and Surgical Sciences and Advanced Technologies, Catania (Italy); Battaglia, Yuri [St. Anna Hospital-University, Department of Specialized Medicine, Division of Nephrology and Dialysis, Ferrara (Italy); Concolino, Daniela [University Magna Graecia, Department of Pediatrics, Catanzaro (Italy); Pieruzzi, Federico [University of Milano-Bicocca, Nephrology Unit, Milan (Italy); Tuttolomondo, Antonino [University of Palermo, Internal Medicine, DiBiMIS, Palermo (Italy); Caronia, Aurelio [Triolo Zancia Care Home, Palermo (Italy); Russo, Cinzia Valeria; Lanzillo, Roberta; Brescia Morra, Vincenzo [University ' ' Federico II' ' , Department of Neurosciences and Reproductive and Odontostomatological Sciences, Naples (Italy)

    2017-06-15

    Multiple sclerosis (MS) has been proposed as a possible differential diagnosis for Fabry disease (FD). The aim of this work was to evaluate the involvement of corpus callosum (CC) on MR images and its possible role as a radiological sign to differentiate between FD and MS. In this multicentric study, we retrospectively evaluated the presence of white matter lesions (WMLs) on the FLAIR images of 104 patients with FD and 117 patients with MS. The incidence of CC-WML was assessed in the two groups and also in a subgroup of 37 FD patients showing neurological symptoms. WMLs were detected in 50 of 104 FD patients (48.1%) and in all MS patients. However, a lesion in the CC was detected in only 3 FD patients (2.9%) and in 106 MS patients (90.6%). In the FD subgroup with neurological symptoms, WMLs were present in 26 of 37 patients (70.3%), with two subjects (5.4%) showing a definite callosal lesion. FD patients have a very low incidence of CC involvement on conventional MR images compared to MS, independently from the clinical presentation and the overall degree of WM involvement. Evaluating the presence of CC lesions on brain MR scans can be used as a radiological sign for a differential diagnosis between MS and FD, rapidly addressing the physician toward a correct diagnosis and subsequent treatment options. (orig.)

  6. Defence responses of arabidopsis thaliana to infection by pseudomonas syringae are regulated by the circadian clock

    KAUST Repository

    Bhardwaj, Vaibhav

    2011-10-31

    The circadian clock allows plants to anticipate predictable daily changes in abiotic stimuli, such as light; however, whether the clock similarly allows plants to anticipate interactions with other organisms is unknown. Here we show that Arabidopsis thaliana (Arabidopsis) has circadian clock-mediated variation in resistance to the virulent bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pst DC3000), with plants being least susceptible to infection in the subjective morning. We suggest that the increased resistance to Pst DC3000 observed in the morning in Col-0 plants results from clock-mediated modulation of pathogen associated molecular pattern (PAMP)-triggered immunity. Analysis of publicly available microarray data revealed that a large number of Arabidopsis defence-related genes showed both diurnal- and circadian-regulation, including genes involved in the perception of the PAMP flagellin which exhibit a peak in expression in the morning. Accordingly, we observed that PAMP-triggered callose deposition was significantly higher in wild-type plants inoculated with Pst DC3000 hrpA in the subjective morning than in the evening, while no such temporal difference was evident in arrhythmic plants. Our results suggest that PAMP-triggered immune responses are modulated by the circadian clock and that temporal regulation allows plants to anticipate and respond more effectively to pathogen challenges in the daytime. © 2011 Bhardwaj et al.

  7. Compensation or inhibitory failure? Testing hypotheses of age-related right frontal lobe involvement in verbal memory ability using structural and diffusion MRI

    Science.gov (United States)

    Cox, Simon R.; Bastin, Mark E.; Ferguson, Karen J.; Allerhand, Mike; Royle, Natalie A.; Maniega, Susanna Muñoz; Starr, John M.; MacLullich, Alasdair M.J.; Wardlaw, Joanna M.; Deary, Ian J.; MacPherson, Sarah E.

    2015-01-01

    Functional neuroimaging studies report increased right prefrontal cortex (PFC) involvement during verbal memory tasks amongst low-scoring older individuals, compared to younger controls and their higher-scoring contemporaries. Some propose that this reflects inefficient use of neural resources through failure of the left PFC to inhibit non-task-related right PFC activity, via the anterior corpus callosum (CC). For others, it indicates partial compensation – that is, the right PFC cannot completely supplement the failing neural network, but contributes positively to performance. We propose that combining structural and diffusion brain MRI can be used to test predictions from these theories which have arisen from fMRI studies. We test these hypotheses in immediate and delayed verbal memory ability amongst 90 healthy older adults of mean age 73 years. Right hippocampus and left dorsolateral prefrontal cortex (DLPFC) volumes, and fractional anisotropy (FA) in the splenium made unique contributions to verbal memory ability in the whole group. There was no significant effect of anterior callosal white matter integrity on performance. Rather, segmented linear regression indicated that right DLPFC volume was a significantly stronger positive predictor of verbal memory for lower-scorers than higher-scorers, supporting a compensatory explanation for the differential involvement of the right frontal lobe in verbal memory tasks in older age. PMID:25241394

  8. The dynamics and endocytosis of Flot1 protein in response to flg22 in Arabidopsis.

    Science.gov (United States)

    Yu, Meng; Liu, Haijiao; Dong, Ziyi; Xiao, Jianwei; Su, Bodan; Fan, Lusheng; Komis, George; Šamaj, Jozef; Lin, Jinxing; Li, Ruili

    2017-08-01

    Membrane microdomains play vital roles in the process of bacterial infection. The membrane microdomain-associated protein Flot1 acts in an endocytic pathway and is required for seedling development, however, whether Flot1 is a part of host defense mechanisms remains unknown. During an analysis of callose deposition, we found that Flot1 amiRNAi mutants exhibited defects in response to flg22. Using variable-angle total internal reflection fluorescence microscopy (VA-TIRFM), structured illumination microscopy (SIM) and fluorescence cross spectroscopy (FCS), we determined that the dynamic behavior of GFP-Flot1 in Arabidopsis thaliana cotyledon epidermal cells changed significantly in plants treated with the elicitor flg22. Moreover, we found that Flot1 was constitutively recycled via an endocytic pathway and that flg22 could promote endocytosis. Importantly, targeting of Flot1 to the late endosome/vacuole for degradation increased in response to flg22 treatment; immunoblot analysis showed that when triggered by flg22, GFP-Flot1 was gradually degraded in a time-dependent manner. Taken together, these findings support the hypothesis that the changing of dynamics and oligomeric states can promote the endocytosis and degradation of Flot1 under flg22 treatment in plant cells. Copyright © 2017 Elsevier GmbH. All rights reserved.

  9. Aluminium reduces sugar uptake in tobacco cell cultures: a potential cause of inhibited elongation but not of toxicity.

    Science.gov (United States)

    Abdel-Basset, Refat; Ozuka, Shotaro; Demiral, Tijen; Furuichi, Takuya; Sawatani, Ikuo; Baskin, Tobias I; Matsumoto, Hideaki; Yamamoto, Yoko

    2010-06-01

    Aluminium is well known to inhibit plant elongation, but the role in this inhibition played by water relations remains unclear. To investigate this, tobacco (Nicotiana tabacum L.) suspension-cultured cells (line SL) was used, treating them with aluminium (50 microM) in a medium containing calcium, sucrose, and MES (pH 5.0). Over an 18 h treatment period, aluminium inhibited the increase in fresh weight almost completely and decreased cellular osmolality and internal soluble sugar content substantially; however, aluminium did not affect the concentrations of major inorganic ions. In aluminium-treated cultures, fresh weight, soluble sugar content, and osmolality decreased over the first 6 h and remained constant thereafter, contrasting with their continued increases in the untreated cultures. The rate of sucrose uptake, measured by radio-tracer, was reduced by approximately 60% within 3 h of treatment. Aluminium also inhibited glucose uptake. In an aluminium-tolerant cell line (ALT301) isogenic to SL, all of the above-mentioned changes in water relations occurred and tolerance emerged only after 6 h and appeared to involve the suppression of reactive oxygen species. Further separating the effects of aluminium on elongation and cell survival, sucrose starvation for 18 h inhibited elongation and caused similar changes in cellular osmolality but stimulated the production of neither reactive oxygen species nor callose and did not cause cell death. We propose that the inhibition of sucrose uptake is a mechanism whereby aluminium inhibits elongation, but does not account for the induction of cell death.

  10. Physiological and molecular analysis of the interaction between aluminium toxicity and drought stress in common bean (Phaseolus vulgaris).

    Science.gov (United States)

    Yang, Zhong-Bao; Eticha, Dejene; Albacete, Alfonso; Rao, Idupulapati Madhusudana; Roitsch, Thomas; Horst, Walter Johannes

    2012-05-01

    Aluminium (Al) toxicity and drought are two major factors limiting common bean (Phaseolus vulgaris) production in the tropics. Short-term effects of Al toxicity and drought stress on root growth in acid, Al-toxic soil were studied, with special emphasis on Al-drought interaction in the root apex. Root elongation was inhibited by both Al and drought. Combined stresses resulted in a more severe inhibition of root elongation than either stress alone. This result was different from the alleviation of Al toxicity by osmotic stress (-0.60 MPa polyethylene glycol) in hydroponics. However, drought reduced the impact of Al on the root tip, as indicated by the reduction of Al-induced callose formation and MATE expression. Combined Al and drought stress enhanced up-regulation of ACCO expression and synthesis of zeatin riboside, reduced drought-enhanced abscisic acid (ABA) concentration, and expression of NCED involved in ABA biosynthesis and the transcription factors bZIP and MYB, thus affecting the regulation of ABA-dependent genes (SUS, PvLEA18, KS-DHN, and LTP) in root tips. The results provide circumstantial evidence that in soil, drought alleviates Al injury, but Al renders the root apex more drought-sensitive, particularly by impacting the gene regulatory network involved in ABA signal transduction and cross-talk with other phytohormones necessary for maintaining root growth under drought.

  11. Salivary testosterone levels are unrelated to handedness or cerebral lateralization for language.

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    Papadatou-Pastou, Marietta; Martin, Maryanne; Mohr, Christine

    2017-03-01

    Behavioural and cerebral lateralization are thought to be controlled, at least in part, by prenatal testosterone (T) levels, explaining why sex differences are found in both laterality traits. The present study investigated hormonal effects on laterality using adult salivary T levels, to explore the adequacy of competing theories: the Geschwind, Behan and Galaburda, the callosal, and the sexual differentiation hypotheses. Sixty participants (15 right-handers and 15 left-handers of each sex) participated. Behavioural lateralization was studied by means of hand preference tests (i.e., the Edinburgh Handedness Inventory and the Quantification of Hand Preference test) and a hand skill test (i.e., the Peg-Moving test) whereas cerebral lateralization for language was studied using the Consonant-Vowel Dichotic Listening test and the Visual Half-Field Lexical Decision test. Salivary T and cortisol (C) concentrations were measured by luminescence immunoassay. Canonical correlations did not reveal significant relationships between T levels and measures of hand preference, hand skill, or language laterality. Thus, our findings add to the growing literature showing no relationship between T concentrations with behavioural or cerebral lateralization. It is claimed that prenatal T is not a major determinant of individual variability in either behavioural or cerebral lateralization.

  12. Gender influence on white matter microstructure: a tract-based spatial statistics analysis.

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    Richard A Kanaan

    Full Text Available BACKGROUND: Sexual dimorphism in human brain structure is well recognised, but less is known about gender differences in white matter microstructure. We used diffusion tensor imaging to explore gender differences in fractional anisotropy (FA, an index of microstructural integrity. We previously found increased FA in the corpus callosum in women, and increased FA in the cerebellum and left superior longitudinal fasciculus (SLF in men, using a whole-brain voxel-based analysis. METHODS: A whole-brain tract-based spatial statistics analysis of 120 matched subjects from the previous analysis, and 134 new subjects (147 men and 107 women in total using a 1.5T scanner, with division into tract-based regions of interest. RESULTS: Men had higher FA in the superior cerebellar peduncles and women had higher FA in corpus callosum in both the first and second samples. The higher SLF FA in men was not found in either sample. DISCUSSION: We confirmed our previous, controversial finding of increased FA in the corpus callosum in women, and increased cerebellar FA in men. The corpus callosum FA difference offers some explanation for the otherwise puzzling advantage in inter-callosal transfer time shown in women; the cerebellar FA difference may be associated with the developmental motor advantage shown in men.

  13. A Case of Gorlin-Goltz Syndrome Presented with Psychiatric Features

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    Amir Mufaddel

    2014-01-01

    Full Text Available We report a case of a 34-year-old male who presented with an acute onset of pleomorphic psychiatric features. Upon examination we later diagnosed him with Gorlin-Goltz syndrome based on clinical and radiological findings that are characteristic for this rare autosomal dominant syndrome. His psychiatric manifestations included irritability, aggressive behavior, labile mood, hallucinations, paranoid delusions, and transient cognitive impairment. His past history indicated surgical excision of pigmented lesion in the left lower eyelid which turned out to be a basal cell carcinoma. His past visits to dermatology clinics indicated pitted keratosis involving hands, callosities, and seborrheic dermatitis. There were numerous palmar pits, and Brain CT Head scan revealed extensive calcification along falx cerebri and around the cerebellar vermis. He had low (20 ng/L vitamin D level and high parathyroid hormone level. The patient improved using antipsychotic medications and vitamin D supplementations for symptomatic management and was discharged with a plan for multispecialty outpatient follow-up. This case highlights the importance of considering rare organic etiologies in the differential diagnosis of patients presenting with psychiatric symptoms. This is of vital importance for early intervention to prevent complications and for better outcomes of the coexistent diseases.

  14. Sugar homeostasis mediated by cell wall invertase GRAIN INCOMPLETE FILLING 1 (GIF1) plays a role in pre-existing and induced defence in rice.

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    Sun, Li; Yang, Dong-lei; Kong, Yu; Chen, Ying; Li, Xiao-Zun; Zeng, Long-Jun; Li, Qun; Wang, Er-Tao; He, Zu-Hua

    2014-02-01

    Sugar metabolism and sugar signalling are not only critical for plant growth and development, but are also important for stress responses. However, how sugar homeostasis is involved in plant defence against pathogen attack in the model crop rice remains largely unknown. In this study, we observed that the grains of gif1, a loss-of-function mutant of the cell wall invertase gene GRAIN INCOMPLETE FILLING 1 (GIF1), were hypersusceptible to postharvest fungal pathogens, with decreased levels of sugars and a thinner glume cell wall in comparison with the wild-type. Interestingly, constitutive expression of GIF1 enhanced resistance to both the rice bacterial pathogen Xanthomonas oryzae pv. oryzae and the fungal pathogen Magnaporthe oryzae. The GIF1-overexpressing (GIF1-OE) plants accumulated higher levels of glucose, fructose and sucrose compared with the wild-type plants. More importantly, higher levels of callose were deposited in GIF1-OE plants during pathogen infection. Moreover, the cell wall was much thicker in the infection sites of the GIF1-OE plants when compared with the wild-type plants. We also found that defence-related genes were constitutively activated in the GIF1-OE plants. Taken together, our study reveals that sugar homeostasis mediated by GIF1 plays an important role in constitutive and induced physical and chemical defence. © 2013 BSPP AND JOHN WILEY & SONS LTD.

  15. Priming of plant innate immunity by rhizobacteria and beta-aminobutyric acid: differences and similarities in regulation.

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    Van der Ent, Sjoerd; Van Hulten, Marieke; Pozo, Maria J; Czechowski, Tomasz; Udvardi, Michael K; Pieterse, Corné M J; Ton, Jurriaan

    2009-01-01

    Pseudomonas fluorescens WCS417r bacteria and beta-aminobutyric acid can induce disease resistance in Arabidopsis, which is based on priming of defence. In this study, we examined the differences and similarities of WCS417r- and beta-aminobutyric acid-induced priming. Both WCS417r and beta-aminobutyric acid prime for enhanced deposition of callose-rich papillae after infection by the oomycete Hyaloperonospora arabidopsis. This priming is regulated by convergent pathways, which depend on phosphoinositide- and ABA-dependent signalling components. Conversely, induced resistance by WCS417r and beta-aminobutyric acid against the bacterial pathogen Pseudomonas syringae are controlled by distinct NPR1-dependent signalling pathways. As WCS417r and beta-aminobutyric acid prime jasmonate- and salicylate-inducible genes, respectively, we subsequently investigated the role of transcription factors. A quantitative PCR-based genome-wide screen for putative WCS417r- and beta-aminobutyric acid-responsive transcription factor genes revealed distinct sets of priming-responsive genes. Transcriptional analysis of a selection of these genes showed that they can serve as specific markers for priming. Promoter analysis of WRKY genes identified a putative cis-element that is strongly over-represented in promoters of 21 NPR1-dependent, beta-aminobutyric acid-inducible WRKY genes. Our study shows that priming of defence is regulated by different pathways, depending on the inducing agent and the challenging pathogen. Furthermore, we demonstrated that priming is associated with the enhanced expression of transcription factors.

  16. Cell wall assembly and intracellular trafficking in plant cells are directly affected by changes in the magnitude of gravitational acceleration.

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    Youssef Chebli

    Full Text Available Plants are able to sense the magnitude and direction of gravity. This capacity is thought to reside in selected cell types within the plant body that are equipped with specialized organelles called statoliths. However, most plant cells do not possess statoliths, yet they respond to changes in gravitational acceleration. To understand the effect of gravity on the metabolism and cellular functioning of non-specialized plant cells, we investigated a rapidly growing plant cell devoid of known statoliths and without gravitropic behavior, the pollen tube. The effects of hyper-gravity and omnidirectional exposure to gravity on intracellular trafficking and on cell wall assembly were assessed in Camellia pollen tubes, a model system with highly reproducible growth behavior in vitro. Using an epi-fluorescence microscope mounted on the Large Diameter Centrifuge at the European Space Agency, we were able to demonstrate that vesicular trafficking is reduced under hyper-gravity conditions. Immuno-cytochemistry confirmed that both in hyper and omnidirectional gravity conditions, the characteristic spatial profiles of cellulose and callose distribution in the pollen tube wall were altered, in accordance with a dose-dependent effect on pollen tube diameter. Our findings suggest that in response to gravity induced stress, the pollen tube responds by modifying cell wall assembly to compensate for the altered mechanical load. The effect was reversible within few minutes demonstrating that the pollen tube is able to quickly adapt to changing stress conditions.

  17. Altered Interhemispheric Functional Coordination in Chronic Tinnitus Patients

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    Yu-Chen Chen

    2015-01-01

    Full Text Available Purpose. Recent studies suggest that tinnitus may be due in part to aberrant callosal structure and interhemispheric interaction. To explore this hypothesis we use a novel method, voxel-mirrored homotopic connectivity (VMHC, to examine the resting-state interhemispheric functional connectivity and its relationships with clinical characteristics in chronic tinnitus patients. Materials and Methods. Twenty-eight chronic tinnitus patients with normal hearing thresholds and 30 age-, sex-, education-, and hearing threshold-matched healthy controls were included in this study and underwent the resting-state fMRI scanning. We computed the VMHC to analyze the interhemispheric functional coordination between homotopic points of the brain in both groups. Results. Compared to the controls, tinnitus patients showed significantly increased VMHC in the middle temporal gyrus, middle frontal gyrus, and superior occipital gyrus. In tinnitus patients, a positive correlation was found between tinnitus duration and VMHC of the uncus. Moreover, correlations between VMHC changes and tinnitus distress were observed in the transverse temporal gyrus, superior temporal pole, precentral gyrus, and calcarine cortex. Conclusions. These results show altered interhemispheric functional connectivity linked with specific tinnitus characteristics in chronic tinnitus patients, which may be implicated in the neuropathophysiology of tinnitus.

  18. Activation of auditory white matter tracts as revealed by functional magnetic resonance imaging

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    Tae, Woo Suk [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Yakunina, Natalia; Nam, Eui-Cheol [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Kangwon National University, Department of Otolaryngology, School of Medicine, Chuncheon, Kangwon-do (Korea, Republic of); Kim, Tae Su [Kangwon National University Hospital, Department of Otolaryngology, Chuncheon (Korea, Republic of); Kim, Sam Soo [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Kangwon National University, Department of Radiology, School of Medicine, Chuncheon (Korea, Republic of)

    2014-07-15

    The ability of functional magnetic resonance imaging (fMRI) to detect activation in brain white matter (WM) is controversial. In particular, studies on the functional activation of WM tracts in the central auditory system are scarce. We utilized fMRI to assess and characterize the entire auditory WM pathway under robust experimental conditions involving the acquisition of a large number of functional volumes, the application of broadband auditory stimuli of high intensity, and the use of sparse temporal sampling to avoid scanner noise effects and increase signal-to-noise ratio. Nineteen healthy volunteers were subjected to broadband white noise in a block paradigm; each run had four sound-on/off alternations and was repeated nine times for each subject. Sparse sampling (TR = 8 s) was used. In addition to traditional gray matter (GM) auditory center activation, WM activation was detected in the isthmus and midbody of the corpus callosum (CC), tapetum, auditory radiation, lateral lemniscus, and decussation of the superior cerebellar peduncles. At the individual level, 13 of 19 subjects (68 %) had CC activation. Callosal WM exhibited a temporal delay of approximately 8 s in response to the stimulation compared with GM. These findings suggest that direct evaluation of the entire functional network of the central auditory system may be possible using fMRI, which may aid in understanding the neurophysiological basis of the central auditory system and in developing treatment strategies for various central auditory disorders. (orig.)

  19. Modulation of cellular redox status by thiamine-activated NADPH oxidase confers Arabidopsis resistance to Sclerotinia sclerotiorum.

    Science.gov (United States)

    Zhou, Jun; Sun, Aizhen; Xing, Da

    2013-08-01

    Sclerotinia sclerotiorum can initially suppress host oxidative burst to aid infection establishment, but later promotes reactive oxygen species (ROS) generation as proliferation advances. Here, it was shown that the cellular redox status can be modulated by thiamine to protect Arabidopsis thaliana against Sclerotinia at the early stages of infection. The initial inhibition of host ROS generation by Sclerotinia-secreted oxalate could effectively be alleviated by thiamine. Thiamine pre-treatment and subsequent wild-type Sclerotinia invasion induced an increase of ascorbate peroxidase activity concomitant with decreased ascorbate/dehydroascorbate ratios, which led to the cellular transition towards oxidative status in infected tissues. Particularly, it was observed that wild-type Sclerotinia, but not oxalate-deficient A2 mutant, could suppress the activity of NADPH oxidase (NOX), which might be an important mechanism underlying the early inhibition of ROS burst. Nevertheless, thiamine pre-treatment followed by wild-type Sclerotinia infection promoted NOX-derived ROS accumulation. Further studies showed that cytosolic Ca(2+) and staurosporine-sensitive protein kinase(s) participated in thiamine-induced activation of NOX. Moreover, thiamine-induced tissue defence responses including callose/lignin deposition and stomatal closure were closely correlated with NOX-derived ROS generation. Additionally, studies with Brassica species indicated that the regulation of thiamine is largely conserved upon Sclerotinia infection. Collectively, it was concluded that thiamine reverses the initial reducing status through activating NOX-dependent ROS signalling to perturb the disease progress of Sclerotinia.

  20. Manipulation of the Xanthophyll Cycle Increases Plant Susceptibility to Sclerotinia sclerotiorum.

    Science.gov (United States)

    Zhou, Jun; Zeng, Lizhang; Liu, Jian; Xing, Da

    2015-05-01

    The xanthophyll cycle is involved in dissipating excess light energy to protect the photosynthetic apparatus in a process commonly assessed from non-photochemical quenching (NPQ) of chlorophyll fluorescence. Here, it is shown that the xanthophyll cycle is modulated by the necrotrophic pathogen Sclerotinia sclerotiorum at the early stage of infection. Incubation of Sclerotinia led to a localized increase in NPQ even at low light intensity. Further studies showed that this abnormal change in NPQ was closely correlated with a decreased pH caused by Sclerotinia-secreted oxalate, which might decrease the ATP synthase activity and lead to a deepening of thylakoid lumen acidification under continuous illumination. Furthermore, suppression (with dithiothreitol) or a defect (in the npq1-2 mutant) of violaxanthin de-epoxidase (VDE) abolished the Sclerotinia-induced NPQ increase. HPLC analysis showed that the Sclerotinia-inoculated tissue accumulated substantial quantities of zeaxanthin at the expense of violaxanthin, with a corresponding decrease in neoxanthin content. Immunoassays revealed that the decrease in these xanthophyll precursors reduced de novo abscisic acid (ABA) biosynthesis and apparently weakened tissue defense responses, including ROS induction and callose deposition, resulting in enhanced plant susceptibility to Sclerotinia. We thus propose that Sclerotinia antagonizes ABA biosynthesis to suppress host defense by manipulating the xanthophyll cycle in early pathogenesis. These findings provide a model of how photoprotective metabolites integrate into the defense responses, and expand the current knowledge of early plant-Sclerotinia interactions at infection sites.

  1. Salicylic acid prevents Trichoderma harzianum from entering the vascular system of roots.

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    Alonso-Ramírez, Ana; Poveda, Jorge; Martín, Ignacio; Hermosa, Rosa; Monte, Enrique; Nicolás, Carlos

    2014-10-01

    Trichoderma is a soil-borne fungal genus that includes species with a significant impact on agriculture and industrial processes. Some Trichoderma strains exert beneficial effects in plants through root colonization, although little is known about how this interaction takes place. To better understand this process, the root colonization of wild-type Arabidopsis and the salicylic acid (SA)-impaired mutant sid2 by a green fluorescent protein (GFP)-marked Trichoderma harzianum strain was followed under confocal microscopy. Trichoderma harzianum GFP22 was able to penetrate the vascular tissue of the sid2 mutant because of the absence of callose deposition in the cell wall of root cells. In addition, a higher colonization of sid2 roots by GFP22 compared with that in Arabidopsis wild-type roots was detected by real-time polymerase chain reaction. These results, together with differences in the expression levels of plant defence genes in the roots of both interactions, support a key role for SA in Trichoderma early root colonization stages. We observed that, without the support of SA, plants were unable to prevent the arrival of the fungus in the vascular system and its spread into aerial parts, leading to later collapse. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  2. Midsagittal corpus callosum area and conversion to multiple sclerosis after clinically isolated syndrome: A multicentre Australian cohort study.

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    Odenthal, Cara; Simpson, Steve; Oughton, Justin; van der Mei, Ingrid; Rose, Stephen; Fripp, Jurgen; Lucas, Robyn; Taylor, Bruce; Dear, Keith; Ponsonby, Anne-Louise; Coulthard, Alan

    2017-08-01

    Patients presenting with clinically isolated syndrome (CIS) may proceed to clinically definite multiple sclerosis (CDMS). Midsagittal corpus callosum area (CCA) is a surrogate marker for callosal atrophy, and can be obtained from a standard MRI study. This study explores the relationship between CCA measured at CIS presentation (baseline) and at 5 years post presentation, with conversion from CIS to CDMS. The association between CCA and markers of disability progression is explored. Corpus callosum area was measured on MRI scans at presentation and 5-year review following diagnosis of a first demyelinating event, or evidence of progressive MS, in 143 participants in the Ausimmune/AusLong Study. Relationships between CCA (at baseline and follow-up) and clinical outcomes were assessed. Mean CCA at baseline study was 6.63 cm2 (SD 1.01). Patients who converted to MS by 5-year review (n = 100) had a significantly smaller mean CCA at follow-up (6.22 vs. 6.74, P = 0.007). Greater CCA reduction was associated with higher annualized relapse rate over follow-up. Baseline CCA obtained from standard MRI protocols may be compared with subsequent MRI examinations as a surrogate for neurodegeneration and cerebral atrophy in patients with MS. This study demonstrates an association between CCA and disability in individuals presenting with CIS who convert to MS. © 2016 The Royal Australian and New Zealand College of Radiologists.

  3. Quantification of the Young's modulus of the primary plant cell wall using Bending-Lab-On-Chip (BLOC).

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    Nezhad, Amir Sanati; Naghavi, Mahsa; Packirisamy, Muthukumaran; Bhat, Rama; Geitmann, Anja

    2013-07-07

    Biomechanical and mathematical modeling of plant developmental processes requires quantitative information about the structural and mechanical properties of living cells, tissues and cellular components. A crucial mechanical property of plant cells is the mechanical stiffness or Young's modulus of its cell wall. Measuring this property in situ at single cell wall level is technically challenging. Here, a bending test is implemented in a chip, called Bending-Lab-On-a-Chip (BLOC), to quantify this biomechanical property for a widely investigated cellular model system, the pollen tube. Pollen along with culture medium is introduced into a microfluidic chip and the growing pollen tube is exposed to a bending force created through fluid loading. The flexural rigidity of the pollen tube and the Young's modulus of the cell wall are estimated through finite element modeling of the observed fluid-structure interaction. An average value of 350 MPa was experimentally estimated for the Young's modulus in longitudinal direction of the cell wall of Camellia pollen tubes. This value is in agreement with the result of an independent method based on cellular shrinkage after plasmolysis and with the mechanical properties of in vitro reconstituted cellulose-callose material.

  4. Tractography of the spider monkey (Ateles geoffroyi corpus callosum using diffusion tensor magnetic resonance imaging.

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    Diana Platas-Neri

    Full Text Available The objective of this research was to describe the organization, connectivity and microstructure of the corpus callosum of the spider monkey (Ateles geoffroyi. Non-invasive magnetic resonance imaging and diffusion-tensor imaging were obtained from three subjects using a 3T Philips scanner. We hypothesized that the arrangement of fibers in spider monkeys would be similar to that observed in other non-human primates. A repeated measure (n = 3 of fractional anisotropy values was obtained of each subject and for each callosal subdivision. Measurements of the diffusion properties of corpus callosum fibers exhibited a similar pattern to those reported in the literature for humans and chimpanzees. No statistical difference was reached when comparing this parameter between the different CC regions (p = 0.066. The highest fractional anisotropy values corresponded to regions projecting from the corpus callosum to the posterior cortical association areas, premotor and supplementary motor cortices. The lowest fractional anisotropy corresponded to projections to motor and sensory cortical areas. Analyses indicated that approximately 57% of the fibers projects to the frontal cortex and 43% to the post-central cortex. While this study had a small sample size, the results provided important information concerning the organization of the corpus callosum in spider monkeys.

  5. Enriched Childhood Experiences Moderate Age-related Motor and Cognitive Decline

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    Megan J. Metzler

    2013-02-01

    Full Text Available Aging is associated with deterioration of skilled manual movement. Specifically, aging corresponds with increased reaction time, greater movement duration, segmentation of movement, increased movement variability, and reduced ability to adapt to external forces and inhibit previously learned sequences. Moreover, it is thought that decreased lateralization of neural function in older adults may point to increased neural recruitment as a compensatory response to deterioration of key frontal and intra-hemispheric networks, particularly of callosal structures. However, factors that mediate age-related motor decline are not well understood. Here we show that music training in childhood is associated with reduced age-related decline of bimanual and unimanual motor skills in a MIDI keyboard motor learning task. Compared to older adults without music training, older adults with more than a year of music training demonstrated proficient bimanual and unimanual movement, evidenced by enhanced speed and decreased movement errors. Further, this group demonstrated significantly better implicit learning in the weather prediction task, a non-motor task. The performance of older adults with music training in those tasks was comparable to young adults. Older adults, however, displayed greater verbal ability compared to young adults irrespective of a past history of music training. Our results indicate that music training early in life may reduce age-associated decline of neural motor and cognitive networks.

  6. Alcohol dehydrogenase 1 (ADH1) confers both abiotic and biotic stress resistance in Arabidopsis.

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    Shi, Haitao; Liu, Wen; Yao, Yue; Wei, Yunxie; Chan, Zhulong

    2017-09-01

    Although the transcriptional regulation and upstream transcription factors of AtADH1 in response to abiotic stress are widely revealed, the in vivo roles of AtADH1 remain unknown. In this study, we found that the expression of AtADH1 was largely induced after salt, drought, cold and pathogen infection. Further studies found that AtADH1 overexpressing plants were more sensitive to abscisic acid (ABA) in comparison to wide type (WT), while AtADH1 knockout mutants showed no significant difference compared with WT in ABA sensitivity. Consistently, AtADH1 overexpressing plants showed improved stress resistance to salt, drought, cold and pathogen infection than WT, but the AtADH1 knockout mutants had no significant difference in abiotic and biotic stress resistance. Moreover, overexpression of AtADH1 expression increased the transcript levels of multiple stress-related genes, accumulation of soluble sugars and callose depositions. All these results indicate that AtADH1 confers enhanced resistance to both abiotic and biotic stresses. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Boron toxicity causes multiple effects on Malus domestica pollen tube growth

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    Kefeng eFang

    2016-02-01

    Full Text Available Boron is an essential micronutrient for plants. However, boron is also toxic to cells at high concentrations, although the mechanism of this stress is not known. This study aimed to evaluate the effect of boron stress on Malus domestica pollen tube growth and its possible regulatory pathway. Our results show that a high concentration of boron inhibited pollen germination and tube growth and led to the morphological abnormality of pollen tubes. Fluorescent labeling coupled with a scanning ion-selective electrode technique detected that boron stress could decrease [Ca2+]c and induce the disappearance of the [Ca2+]c gradient, which are critical for pollen tube polar growth. Actin filaments were therefore altered by boron stress. Immuno-localization and fluorescence labeling, together with Fourier-transform infrared analysis (FTIR, suggested that boron stress influenced the accumulation and distribution of callose, de-esterified pectins, esterified pectins and arabinogalactan proteins in pollen tubes. All of the above results provide new insights into the regulatory role of boron in pollen tube development. In summary, boron likely plays a structural and regulatory role in relation to [Ca2+]c, actin cytoskeleton and cell wall components and thus regulates Malus domestica pollen germination and tube polar growth.

  8. Assessment of the hemispheric lateralization of grapheme-color synesthesia with Stroop-type tests.

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    Ruiz, Mathieu J; Hupé, Jean-Michel

    2015-01-01

    Grapheme-color synesthesia, the idiosyncratic, arbitrary association of colors to letters or numbers, develops in childhood once reading is mastered. Because language processing is strongly left-lateralized in most individuals, we hypothesized that grapheme-color synesthesia could be left-lateralized as well. We used synesthetic versions of the Stroop test with colored letters and numbers presented either in the right or the left visual field of thirty-four synesthetes. Interference by synesthetic colors was stronger for stimuli in the right hemifield (first experiment, color naming task). Synesthetes were also faster in the right hemifield when naming the synesthetic color of graphemes (second experiment). Overall, the lateralization effect was 7 ms (the 95% confidence interval was [1.5 12] ms), a delay compatible with an additional callosal transfer for stimuli presented in the left hemifield. Though weak, this effect suggests that the association of synesthetic colors to graphemes may be preferentially processed in the left hemisphere. We speculate that this left-lateralization could be a landmark of synesthetic grapheme-color associations, if not found for color associations learnt by non-synesthete adults.

  9. Assessment of the hemispheric lateralization of grapheme-color synesthesia with Stroop-type tests.

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    Mathieu J Ruiz

    Full Text Available Grapheme-color synesthesia, the idiosyncratic, arbitrary association of colors to letters or numbers, develops in childhood once reading is mastered. Because language processing is strongly left-lateralized in most individuals, we hypothesized that grapheme-color synesthesia could be left-lateralized as well. We used synesthetic versions of the Stroop test with colored letters and numbers presented either in the right or the left visual field of thirty-four synesthetes. Interference by synesthetic colors was stronger for stimuli in the right hemifield (first experiment, color naming task. Synesthetes were also faster in the right hemifield when naming the synesthetic color of graphemes (second experiment. Overall, the lateralization effect was 7 ms (the 95% confidence interval was [1.5 12] ms, a delay compatible with an additional callosal transfer for stimuli presented in the left hemifield. Though weak, this effect suggests that the association of synesthetic colors to graphemes may be preferentially processed in the left hemisphere. We speculate that this left-lateralization could be a landmark of synesthetic grapheme-color associations, if not found for color associations learnt by non-synesthete adults.

  10. Pathophysiology and Treatment of Alien Hand Syndrome

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    Harini Sarva

    2014-12-01

    Full Text Available Background: Alien hand syndrome (AHS is a disorder of involuntary, yet purposeful, hand movements that may be accompanied by agnosia, aphasia, weakness, or sensory loss. We herein review the most reported cases, current understanding of the pathophysiology, and treatments.Methods: We performed a PubMed search in July of 2014 using the phrases “alien hand syndrome,” “alien hand syndrome pathophysiology,” “alien hand syndrome treatment,” and “anarchic hand syndrome.” The search yielded 141 papers (reviews, case reports, case series, and clinical studies, of which we reviewed 109. Non‐English reports without English abstracts were excluded.Results: Accumulating evidence indicates that there are three AHS variants: frontal, callosal, and posterior. Patients may demonstrate symptoms of multiple types; there is a lack of correlation between phenomenology and neuroimaging findings. Most pathologic and functional imaging studies suggest network disruption causing loss of inhibition as the likely cause. Successful interventions include botulinum toxin injections, clonazepam, visuospatial coaching techniques, distracting the affected hand, and cognitive behavioral therapy.Discussion: The available literature suggests that overlap between AHS subtypes is common. The evidence for effective treatments remains anecdotal, and, given the rarity of AHS, the possibility of performing randomized, placebo‐controlled trials seems unlikely. As with many other interventions for movement disorders, identifying the specific functional impairments caused by AHS may provide the best guidance towards individualized supportive care.

  11. Human von Economo neurons express transcription factors associated with Layer V subcerebral projection neurons.

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    Cobos, Inma; Seeley, William W

    2015-01-01

    The von Economo neurons (VENs) are large bipolar Layer V projection neurons found chiefly in the anterior cingulate and frontoinsular cortices. Although VENs have been linked to prevalent illnesses such as frontotemporal dementia, autism, and schizophrenia, little is known about VEN identity, including their major projection targets. Here, we undertook a developmental transcription factor expression study, focusing on markers associated with specific classes of Layer V projection neurons. Using mRNA in situ hybridization, we found that VENs prominently express FEZF2 and CTIP2, transcription factors that regulate the fate and differentiation of subcerebral projection neurons, in humans aged 3 months to 65 years. In contrast, few VENs expressed markers associated with callosal or corticothalamic projections. These findings suggest that VENs may represent a specialized Layer V projection neuron for linking cortical autonomic control sites to brainstem or spinal cord regions. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Arabidopsis ubiquitin ligase PUB12 interacts with and negatively regulates Chitin Elicitor Receptor Kinase 1 (CERK1.

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    Koji Yamaguchi

    Full Text Available In Arabidopsis, fungal chitin is recognized as a pathogen-associated molecular pattern (PAMP by the chitin receptor complex containing the lysin-motif (LysM receptor-like kinases CERK1 and LYK5. Upon the perception of chitin, CERK1 phosphorylates the receptor-like cytoplasmic kinase, PBL27, which activates the intracellular mitogen-activated protein kinase (MAPK cascade. However, the mechanisms by which the CERK1-PBL27 complex is regulated remain largely unknown. We identified ubiquitin ligase PUB12 as a component of the PBL27 complex using co-immunoprecipitation and mass spectrometry. However, PUB12 did not interact directly with PBL27. Instead, the ARM domains of PUB12 and its paralog PUB13 interacted with the intracellular domain of CERK1 in a manner that was dependent on its autophosphorylation, suggesting that the phosphorylation-based auto-activation of CERK1 may be required for its interaction with PUB12. The co-expression of PUB12 in Nicotiana benthamiana reduced the accumulation of CERK1. The pub12 pub13 mutant exhibited enhanced chitin-induced immune responses such as ROS production, MAPK activation, and callose deposition. These results suggest that PUB12 and PUB13 are involved in the negative regulation of the chitin receptor complex, which may contribute to the transient desensitization of chitin-induced responses.

  13. Development of successive cambia and wood structure in stem of Rivea hypocriteriformis (Convolvulaceae

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    Rajput Kishore S.

    2016-07-01

    Full Text Available This study examined the formation of successive rings of cambia in Rivea hypocriteriformis Choisy (Convolvulaceae. The mature stem is composed of four to five rings of xylem alternating with phloem. Successive cambia originate as smaller and larger segments; union and anastomosing of small cambial segments often leads to the formation of discontinuous rings. In the initial stage of growth, several vascular bundles interconnect to form the first ring of vascular cambium. The cambium remains functional for one complete season and becomes dormant during summer; a new ring of cambium is completed prior to the subsequent monsoon season and sprouting of new leaves. Successive cambia are initiated from the pericyclic parenchyma situated three to four cell layers outside of the protophloem. Functionally, all the successive cambia are bidirectional and produce secondary xylem centripetally and phloem centrifugally. The secondary xylem is diffuse-porous, with indistinct growth rings and consisting of wide fibriform vessels, fibre tracheids, and axial and ray parenchyma cells. The xylem rays are uni- to multiseriate and heterocellular. The multiseriate rays contain lignified marginal ray cells and thin-walled, unlignified central cells. The central ray cells also show accumulations of starch and druses. Discrete strands of intraxylary phloem occur at the periphery of the pith, and additional intraxylary phloem develops from adjacent cells as secondary growth progresses. Earlier-formed phloem shows heavy accumulation of callose, followed by its compaction. The development of successive cambia is correlated with extension growth and with the phenology of the plant.

  14. Endoport-assisted microsurgical resection of cerebral cavernous malformations.

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    Ding, Dale; Starke, Robert M; Crowley, R Webster; Liu, Kenneth C

    2015-06-01

    The aim of this case series is to describe the surgical technique and postoperative outcomes for endoport-assisted microsurgical resection (EAMR) of cerebral cavernous malformations (CCM). Significant manipulation of subcortical white matter tracts may be necessary for the successful resection of CCM located in deep brain regions. Minimally invasive neurosurgical devices such as endoport systems can decrease disruption of the cortex and white matter tracts overlying deep-seated CCM through small cranial and dural openings. The role of endoport technology in modern CCM surgery is incompletely understood. Three patients with symptomatic CCM underwent EAMR at our institution using the BrainPath endoport system (NICO Corporation, Indianapolis, IN, USA). Complete resection was achieved in two patients. One patient with a large 4.5cm callosal CCM was left with a small residual lesion. There were no postoperative complications and all patients were functionally independent (modified Rankin Scale score 2 or less) at follow-up. Based on our initial experience with EAMR for CCM we believe the endoport can be an effective alternative to traditional retractor systems. Due to the nature of the small craniotomy and durotomy performed for endoport placement EAMR has the potential to improve surgical outcomes by reducing postoperative pain, analgesic requirements and hospital stays. Therefore, EAMR may be considered for appropriately selected CCM patients, although additional experience is necessary to improve our understanding of its role in CCM management. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Dermatological changes of amputation stump

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    Arora P

    1993-01-01

    Full Text Available Dermatological changes of stumps of 174 amputees are presented. The commonest dermatological change recorded at the site of amputation stump was hyperpigmentation in 46 (26.4% followed by callosities in 32 (18.3%, scaling in 29 (16.7%, cutaneous atrophy in 20 (11.5%, lichenification in 19(10.9%, traumatic ulcer and bacterial infections in 18 (10.3% each, hypertrophic scar in 14 (8.1%, hypopigmentation and corns in 13 (7.4% each, verrucous hypertrophy of stump in 12 (6.9%, dermatophytic infection in 5(2.9%, stump oedema and phantom limb in 4 (2.3% each, intertriginous dermatitis in 3( 1.7%, allergic contact dermatitis (resin and frictional eczema in 2(1.1% each. Epidermoid cyst, keloid formation, anaesthesia, gangrene and cutaneous horn were recorded in 1 (0.6% each. Atrophy (epidermal and derma, anaesthesia, alopecia and elephantiasis of the stump have not been documented in the literature earlier.

  16. Deletion 1q43 encompassing only CHRM3 in a patient with autistic disorder.

    Science.gov (United States)

    Petersen, Andrea Klunder; Ahmad, Ausaf; Shafiq, Mustafa; Brown-Kipphut, Brigette; Fong, Chin-To; Anwar Iqbal, M

    2013-02-01

    Deletions on the distal portion of the long arm of chromosome 1 result in complex and highly variable clinical phenotypes which include intellectual disability, autism, seizures, microcephaly/craniofacial dysmorphology, corpus callosal agenesis/hypogenesis, cardiac and genital anomalies, hand and foot abnormalities and short stature. Genotype-phenotype correlation reported a minimum region of 2 Mb at 1q43-q44. We report on a 3 ½ year old male patient diagnosed with autistic disorder who has social withdrawal, eating problems, repetitive stereotypic behaviors including self-injurious head banging and hair pulling, and no seizures, anxiety, or mood swings. Array comparative genomic hybridization (aCGH) showed an interstitial deletion of 473 kb at 1q43 region (239,412,391-239,885,394; NCBI build37/hg19) harboring only CHRM3 (Acetylcholine Receptor, Muscarinic, 3; OMIM: 118494). Recently, another case with a de novo interstitial deletion of 911 kb at 1q43 encompassing three genes including CHRM3 was reported. The M3 muscarinic receptor influences a multitude of central and peripheral nervous system processes via its interaction with acetylcholine and may be an important modulator of behavior, learning and memory. We propose CHRM3 as a candidate gene responsible for our patient's specific phenotype as well as the overlapping phenotypic features of other patients with 1q43 or 1q43-q44 deletions. Copyright © 2013. Published by Elsevier Masson SAS.

  17. Response of sweet orange (Citrus sinensis) to 'Candidatus Liberibacter asiaticus' infection: microscopy and microarray analyses.

    Science.gov (United States)

    Kim, Jeong-Soon; Sagaram, Uma Shankar; Burns, Jacqueline K; Li, Jian-Liang; Wang, Nian

    2009-01-01

    Citrus greening or huanglongbing (HLB) is a devastating disease of citrus. HLB is associated with the phloem-limited fastidious prokaryotic alpha-proteobacterium 'Candidatus Liberibacter spp.' In this report, we used sweet orange (Citrus sinensis) leaf tissue infected with 'Ca. Liberibacter asiaticus' and compared this with healthy controls. Investigation of the host response was examined with citrus microarray hybridization based on 33,879 expressed sequence tag sequences from several citrus species and hybrids. The microarray analysis indicated that HLB infection significantly affected expression of 624 genes whose encoded proteins were categorized according to function. The categories included genes associated with sugar metabolism, plant defense, phytohormone, and cell wall metabolism, as well as 14 other gene categories. The anatomical analyses indicated that HLB bacterium infection caused phloem disruption, sucrose accumulation, and plugged sieve pores. The up-regulation of three key starch biosynthetic genes including ADP-glucose pyrophosphorylase, starch synthase, granule-bound starch synthase and starch debranching enzyme likely contributed to accumulation of starch in HLB-affected leaves. The HLB-associated phloem blockage resulted from the plugged sieve pores rather than the HLB bacterial aggregates since 'Ca. Liberibacter asiaticus' does not form aggregate in citrus. The up-regulation of pp2 gene is related to callose deposition to plug the sieve pores in HLB-affected plants.

  18. Cell Wall Composition, Biosynthesis and Remodeling during Pollen Tube Growth

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    Jean-Claude Mollet

    2013-03-01

    Full Text Available The pollen tube is a fast tip-growing cell carrying the two sperm cells to the ovule allowing the double fertilization process and seed setting. To succeed in this process, the spatial and temporal controls of pollen tube growth within the female organ are critical. It requires a massive cell wall deposition to promote fast pollen tube elongation and a tight control of the cell wall remodeling to modify the mechanical properties. In addition, during its journey, the pollen tube interacts with the pistil, which plays key roles in pollen tube nutrition, guidance and in the rejection of the self-incompatible pollen. This review focuses on our current knowledge in the biochemistry and localization of the main cell wall polymers including pectin, hemicellulose, cellulose and callose from several pollen tube species. Moreover, based on transcriptomic data and functional genomic studies, the possible enzymes involved in the cell wall remodeling during pollen tube growth and their impact on the cell wall mechanics are also described. Finally, mutant analyses have permitted to gain insight in the function of several genes involved in the pollen tube cell wall biosynthesis and their roles in pollen tube growth are further discussed.

  19. Plasmodesmata: channels for intercellular signaling during plant growth and development.

    Science.gov (United States)

    Sevilem, Iris; Yadav, Shri Ram; Helariutta, Ykä

    2015-01-01

    Plants have evolved strategies for short- and long-distance communication to coordinate plant development and to adapt to changing environmental conditions. Plasmodesmata (PD) are intercellular nanochannels that provide an effective pathway for both selective and nonselective movement of various molecules that function in diverse biological processes. Numerous non-cell-autonomous proteins (NCAP) and small RNAs have been identified that have crucial roles in cell fate determination and organ patterning during development. Both the density and aperture size of PD are developmentally regulated, allowing formation of spatial symplastic domains for establishment of tissue-specific developmental programs. The PD size exclusion limit (SEL) is controlled by reversible deposition of callose, as well as by some PD-associated proteins. Although a large number of PD-associated proteins have been identified, many of their functions remain unknown. Despite the fact that PD are primarily membranous structures, surprisingly very little is known about their lipid composition. Thus, future studies in PD biology will provide deeper insights into the high-resolution structure and tightly regulated functions of PD and the evolution of PD-mediated cell-to-cell communication in plants.

  20. Innate immune responses activated in Arabidopsis roots by microbe-associated molecular patterns.

    Science.gov (United States)

    Millet, Yves A; Danna, Cristian H; Clay, Nicole K; Songnuan, Wisuwat; Simon, Matthew D; Werck-Reichhart, Danièle; Ausubel, Frederick M

    2010-03-01

    Despite the fact that roots are the organs most subject to microbial interactions, very little is known about the response of roots to microbe-associated molecular patterns (MAMPs). By monitoring transcriptional activation of beta-glucuronidase reporters and MAMP-elicited callose deposition, we show that three MAMPs, the flagellar peptide Flg22, peptidoglycan, and chitin, trigger a strong tissue-specific response in Arabidopsis thaliana roots, either at the elongation zone for Flg22 and peptidoglycan or in the mature parts of the roots for chitin. Ethylene signaling, the 4-methoxy-indole-3-ylmethylglucosinolate biosynthetic pathway, and the PEN2 myrosinase, but not salicylic acid or jasmonic acid signaling, play major roles in this MAMP response. We also show that Flg22 induces the cytochrome P450 CYP71A12-dependent exudation of the phytoalexin camalexin by Arabidopsis roots. The phytotoxin coronatine, an Ile-jasmonic acid mimic produced by Pseudomonas syringae pathovars, suppresses MAMP-activated responses in the roots. This suppression requires the E3 ubiquitin ligase COI1 as well as the transcription factor JIN1/MYC2 but does not rely on salicylic acid-jasmonic acid antagonism. These experiments demonstrate the presence of highly orchestrated and tissue-specific MAMP responses in roots and potential pathogen-encoded mechanisms to block these MAMP-elicited signaling pathways.

  1. Innate Immune Responses Activated in Arabidopsis Roots by Microbe-Associated Molecular Patterns[W][OA

    Science.gov (United States)

    Millet, Yves A.; Danna, Cristian H.; Clay, Nicole K.; Songnuan, Wisuwat; Simon, Matthew D.; Werck-Reichhart, Danièle; Ausubel, Frederick M.

    2010-01-01

    Despite the fact that roots are the organs most subject to microbial interactions, very little is known about the response of roots to microbe-associated molecular patterns (MAMPs). By monitoring transcriptional activation of β-glucuronidase reporters and MAMP-elicited callose deposition, we show that three MAMPs, the flagellar peptide Flg22, peptidoglycan, and chitin, trigger a strong tissue-specific response in Arabidopsis thaliana roots, either at the elongation zone for Flg22 and peptidoglycan or in the mature parts of the roots for chitin. Ethylene signaling, the 4-methoxy-indole-3-ylmethylglucosinolate biosynthetic pathway, and the PEN2 myrosinase, but not salicylic acid or jasmonic acid signaling, play major roles in this MAMP response. We also show that Flg22 induces the cytochrome P450 CYP71A12-dependent exudation of the phytoalexin camalexin by Arabidopsis roots. The phytotoxin coronatine, an Ile-jasmonic acid mimic produced by Pseudomonas syringae pathovars, suppresses MAMP-activated responses in the roots. This suppression requires the E3 ubiquitin ligase COI1 as well as the transcription factor JIN1/MYC2 but does not rely on salicylic acid–jasmonic acid antagonism. These experiments demonstrate the presence of highly orchestrated and tissue-specific MAMP responses in roots and potential pathogen-encoded mechanisms to block these MAMP-elicited signaling pathways. PMID:20348432

  2. Activation of Plant Innate Immunity by Extracellular High Mobility Group Box 3 and Its Inhibition by Salicylic Acid.

    Directory of Open Access Journals (Sweden)

    Hyong Woo Choi

    2016-03-01

    Full Text Available Damage-associated molecular pattern molecules (DAMPs signal the presence of tissue damage to induce immune responses in plants and animals. Here, we report that High Mobility Group Box 3 (HMGB3 is a novel plant DAMP. Extracellular HMGB3, through receptor-like kinases BAK1 and BKK1, induced hallmark innate immune responses, including i MAPK activation, ii defense-related gene expression, iii callose deposition, and iv enhanced resistance to Botrytis cinerea. Infection by necrotrophic B. cinerea released HMGB3 into the extracellular space (apoplast. Silencing HMGBs enhanced susceptibility to B. cinerea, while HMGB3 injection into apoplast restored resistance. Like its human counterpart, HMGB3 binds salicylic acid (SA, which results in inhibition of its DAMP activity. An SA-binding site mutant of HMGB3 retained its DAMP activity, which was no longer inhibited by SA, consistent with its reduced SA-binding activity. These results provide cross-kingdom evidence that HMGB proteins function as DAMPs and that SA is their conserved inhibitor.

  3. Cellulose synthesizing Complexes in Vascular Plants andProcaryotes

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard M, Jr; Saxena, Inder Mohan

    2009-07-07

    Continuing the work initiated under DE-FG03-94ER20145, the following major accomplishments were achieved under DE-FG02-03ER15396 from 2003-2007: (a) we purified the acsD gene product of the Acetobacter cellulose synthase operon as well as transferred the CesA cellulose gene from Gossypium into E. coli in an attempt to crystallize this protein for x-ray diffraction structural analysis; however, crystallization attempts proved unsuccessful; (b) the Acetobacter cellulose synthase operon was successfully incorporated into Synechococcus, a cyanobacterium2; (c) this operon in Synechococcus was functionally expressed; (d) we successfully immunolabeled Vigna cellulose and callose synthase components and mapped their distribution before and after wounding; (e) we developed a novel method to produce replicas of cellulose synthases in tobacco BY-2 cells, and we demonstrated the cytoplasmic domain of the rosette TC; (f) from the moss Physcomitrella, we isolated two full-length cDNA sequences of cellulose synthase (PpCesA1 and PpCesA2) and attempted to obtain full genomic DNA sequences; (g) we examined the detailed molecular structure of a new form of non-crystalline cellulose known as nematic ordered cellulose (=NOC)3.

  4. Morphometry of the corpus callosum in Chinese children: relationship with gender and academic performance

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Wing Hung Alex; Chan, Yu.Lung [Prince of Wales Hospital, Department of Diagnostic Radiology and Organ Imaging, Shatin, Hong Kong (Hong Kong); Au, Kit Sum Agnes [James Cook University, Department of Psychology, Townsville, Queensland (Australia); Yeung, Ka Wai David; Kwan, Ting Fai; To, Cho Yee

    2005-06-01

    The corpus callosum has been widely studied, but no study has demonstrated whether its size and shape have any relationship with language and calculation performance. To examine the morphometry of the corpus callosum of normal Chinese children and its relationship with gender and academic performance. One hundred primary school children (63 boys, 37 girls; age 6.5-10 years) were randomly selected and the standardized academic performance for each was ascertained. On the mid-sagittal section of a brain MRI, the length, height and total area of the corpus callosum and its thickness at different sites were measured. These were correlated with sex and academic performance. Apart from the normal average dimension of the different parts of the corpus callosum, thickness at the body-splenium junction in the average-to-good performance group was significantly greater than the below-average performance group in Chinese language (P=0.005), English language (P=0.02) and mathematics (P=0.01). The remainder of the callosal thickness showed no significant relationship with academic performance. There was no significant sex difference in the thickness of any part of the corpus callosum. These findings raise the suggestion that language and mathematics proficiency may be related to the morphometry of the fibre connections in the posterior parietal lobes. (orig.)

  5. Rey Visual Design Learning Test performance correlates with white matter structure.

    Science.gov (United States)

    Begré, Stefan; Kiefer, Claus; von Känel, Roland; Frommer, Angela; Federspiel, Andrea

    2009-04-01

    Studies exploring relation of visual memory to white matter are extensively lacking. The Rey Visual Design Learning Test (RVDLT) is an elementary motion, colour and word independent visual memory test. It avoids a significant contribution from as many additional higher order visual brain functions as possible to visual performance, such as three-dimensional, colour, motion or word-dependent brain operations. Based on previous results, we hypothesised that test performance would be related with white matter of dorsal hippocampal commissure, corpus callosum, posterior cingulate, superior longitudinal fascicle and internal capsule. In 14 healthy subjects, we measured intervoxel coherence (IC) by diffusion tensor imaging as an indication of connectivity and visual memory performance measured by the RVDLT. IC considers the orientation of the adjacent voxels and has a better signal-to-noise ratio than the commonly used fractional anisotropy index. Using voxelwise linear regression analyses of the IC values, we found a significant and direct relationship between 11 clusters and visual memory test performance. The fact that memory performance correlated with white matter structure in left and right dorsal hippocampal commissure, left and right posterior cingulate, right callosal splenium, left and right superior longitudinal fascicle, right medial orbitofrontal region, left anterior cingulate, and left and right anterior limb of internal capsule emphasises our hypothesis. Our observations in healthy subjects suggest that individual differences in brain function related to the performance of a task of higher cognitive demands might partially be associated with structural variation of white matter regions.

  6. Area-specific development of distinct projection neuron subclasses is regulated by postnatal epigenetic modifications.

    Science.gov (United States)

    Harb, Kawssar; Magrinelli, Elia; Nicolas, Céline S; Lukianets, Nikita; Frangeul, Laura; Pietri, Mariel; Sun, Tao; Sandoz, Guillaume; Grammont, Franck; Jabaudon, Denis; Studer, Michele; Alfano, Christian

    2016-01-27

    During cortical development, the identity of major classes of long-distance projection neurons is established by the expression of molecular determinants, which become gradually restricted and mutually exclusive. However, the mechanisms by which projection neurons acquire their final properties during postnatal stages are still poorly understood. In this study, we show that the number of neurons co-expressing Ctip2 and Satb2, respectively involved in the early specification of subcerebral and callosal projection neurons, progressively increases after birth in the somatosensory cortex. Ctip2/Satb2 postnatal co-localization defines two distinct neuronal subclasses projecting either to the contralateral cortex or to the brainstem suggesting that Ctip2/Satb2 co-expression may refine their properties rather than determine their identity. Gain- and loss-of-function approaches reveal that the transcriptional adaptor Lmo4 drives this maturation program through modulation of epigenetic mechanisms in a time- and area-specific manner, thereby indicating that a previously unknown genetic program postnatally promotes the acquisition of final subtype-specific features.

  7. Skin manifestations of athletes competing in the summer olympics: what a sports medicine physician should know.

    Science.gov (United States)

    De Luca, Jacqueline F; Adams, Brian B; Yosipovitch, Gil

    2012-05-01

    Olympic athletes are vulnerable to traumatic, environmental and infectious skin manifestations. Although dermatological complaints are frequent among Olympians, there is a scarcity of literature that reviews sports-related dermatoses among Olympic athletes. A comprehensive review of PREMEDLINE and MEDLINE searches of all available literature through to January 2011 was conducted, focusing on sports-related dermatological presentations as well as the key words 'Olympic athletes' and 'skin diseases'. Common skin conditions can be harmful and even prohibitive for competition. Common aetiologies of dermatological conditions related to sports include: skin infections with dermatophytes such as tinea pedis and tinea corporis, bacteria such as pitted keratolysis, and folliculitis and viruses such as herpes gladiatorum. Frictional dermatoses occur commonly and include athlete's nodules, jogger's itch, frictional blisters, callosities and talon noir. Trauma can cause haematomas such as auricular haematomas. Due to long training hours in the sun, many endurance athletes experience high levels of UV radiation and a higher risk for both melanoma and non-melanoma skin cancer. Pre-existing dermatoses can also be aggravated with practice and competition; in particular, atopic eczema and physical urticarias. Infrequent dermatoses are susceptible to misdiagnosis, delay in treatment and needless biopsies. This review highlights the diagnosis and management of sports-related dermatoses by the following general categories of Olympic sport: endurance, resistance, team sport, and performing arts.

  8. Development of gravitropic response: unusual behavior of flax phloem G-fibers.

    Science.gov (United States)

    Ibragimova, Nadezda N; Ageeva, Marina V; Gorshkova, Tatyana A

    2017-03-01

    The major mechanism of gravitropism that is discussed for herbal plants is based on the nonuniform elongation of cells located on the opposite stem sides, occurring in the growing zone of an organ. However, gravitropic response of flax (Linum usitatissimum L.) is well-pronounced in the lower half of developing stem, which has ceased elongation long in advance of plant inclination. We have analyzed the stem curvature region by various approaches of microscopy and found the undescribed earlier significant modifications in primary phloem fibers that have constitutively developed G-layer. In fibers on the pulling stem side, cell portions were widened with formation of "bottlenecks" between them, leading to the "sausage-like" shape of a cell. Lumen diameter in fiber widening increased, while cell wall thickness decreased. Callose was deposited in proximity to bottlenecks and sometimes totally occluded their lumen. Structure of fiber cell wall changed considerably, with formation of breaks between G- and S-layers. Thick fibrillar structures that were revealed in fiber cell wall by light microscopy got oblique orientation instead of parallel to the fiber axis one in control plants. The described changes occurred at various combinations of gravitational and mechanical stimuli. Thus, phloem fibers with constitutively formed gelatinous cell wall, located in nonelongating parts of herbal plant, are involved in gravitropism and may become an important element in general understanding of the gravity effects on plants. We suggest flax phloem fibers as the model system to study the mechanism of plant position correction, including signal perception and transduction.

  9. T2 relaxometry of brain in myotonic dystrophy

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    Di Costanzo, A.; Bonavita, V.; Tedeschi, G. [Inst. of Neurological Sciences, 2. Univ. of Naples (Italy); Di Salle, F. [Dept. of Biomorphological and Functional Sciences, Univ. ' ' Federico II' ' , Naples (Italy); Santoro, L. [Dept. of Neurological Sciences, University ' ' Federico II' ' , Naples (Italy)

    2001-03-01

    We investigated the nature and extent of brain involvement in myotonic dystrophy (DM), examining possible T2 relaxation abnormalities in the brain of 20 patients with adult-onset DM and 20 sex- and age-matched normal controls. Brain MRI was performed at 0.5 T, and T2 values were calculated from signal intensity in two echoes. Regions of interest included: frontal, parietal, temporal, occipital and callosal (rostral and splenial) normal-appearing white matter; frontal, occipital, insular and hippocampal cortex; caudate nucleus, putamen, globus pallidus and thalamus. All white-matter and occipital and right frontal cortex regions showed a significantly longer T2 in the patients. Multiple regression analysis, including grey- and white-matter T2 as dependent variables, plus age at onset and at imaging, disease duration, muscular disability, brain atrophy and CTG trinucleotide repeats as independent variables, revealed that only white-matter T2 elongation and disease duration correlated positively. White-matter involvement in DM is more extensive than previously reported by MRI and neuropathological studies and seems to be progressive in the course of disease. (orig.)

  10. Case Report: 84 year-old woman with alien hand syndrome [version 1; referees: 2 approved, 1 approved with reservations

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    Ihtesham Aatif Qureshi

    2016-07-01

    Full Text Available Background: Alien hand syndrome [AHS] is a rare and ill-defined neurological disorder. It produces complex, goal-directed motion of one hand that is involuntarily instigated. This syndrome characteristically arises after brain trauma, brain surgery, stroke or encephalitis. We describe a case of AHS in a patient who had a previous episode of subarachnoid hemorrhage affecting the left frontal lobe and corpus callosum. Case presentation: An 84-year-old woman presented to the emergency department complaining of headaches and several episodes of her left arm moving as if it was groping around trying to grab at her own body. A computed tomography scan of the head demonstrated an acute left superior frontal hemorrhage with compression of the corpus callosum. Transcranial Doppler report showed no significant abnormality in the insonated vessels. After being stabilized for the acute bleed, she was treated with clonazepam 0.5 mgat night for the uncontrolled hand movements. Her movements resolved by her next month follow up. The diagnosis of AHS was made based on her clinical presentation, characterization of the movement and localization correlating with findings in neuroimaging. Conclusion: We document a rare neurologic disorder seen in patients presenting with a history of previous strokes and a typical description of involuntary and unintentional, uncontrolled unilateral arm movements with repetitive grasping. The present case has a combination of frontal and callosal lesions.  These findings appear to support a potential destruction leading to the rare syndrome.

  11. Suppression of plant defenses by a Myzus persicae (green peach aphid) salivary effector protein.

    Science.gov (United States)

    Elzinga, Dezi A; De Vos, Martin; Jander, Georg

    2014-07-01

    The complex interactions between aphids and their host plant are species-specific and involve multiple layers of recognition and defense. Aphid salivary proteins, which are released into the plant during phloem feeding, are a likely mediator of these interactions. In an approach to identify aphid effectors that facilitate feeding from host plants, eleven Myzus persicae (green peach aphid) salivary proteins and the GroEL protein of Buchnera aphidicola, a bacterial endosymbiont of this aphid species, were expressed transiently in Nicotiana tabacum (tobacco). Whereas two salivary proteins increased aphid reproduction, expression of three other aphid proteins and GroEL significantly decreased aphid reproduction on N. tabacum. These effects were recapitulated in stable transgenic Arabidopsis thaliana plants. Further experiments with A. thaliana expressing Mp55, a salivary protein that increased aphid reproduction, showed lower accumulation of 4-methoxyindol-3-ylmethylglucosinolate, callose and hydrogen peroxide in response to aphid feeding. Mp55-expressing plants also were more attractive for aphids in choice assays. Silencing Mp55 gene expression in M. persicae using RNA interference approaches reduced aphid reproduction on N. tabacum, A. thaliana, and N. benthamiana. Together, these results demonstrate a role for Mp55, a protein with as-yet-unknown molecular function, in the interaction of M. persicae with its host plants.

  12. Impact of in utero exposure to EtOH on corpus callosum development and paw preference in rats: protective effects of silymarin

    Directory of Open Access Journals (Sweden)

    Montoya Rebecca

    2002-11-01

    Full Text Available Abstract Background Using a rat model we have found that the bioflavonoid silymarin (SY ameliorates some of the negative consequences of in utero exposure to ethanol (EtOH. In the current study our aim was to determine if laterality preference and corpus callosum development were altered in rat offspring whose mothers were provided with a concomitant administration of SY with EtOH throughout gestation. Methods We provided pregnant Fisher/344 rats with liquid diets containing 35% ethanol derived calories (EDC throughout the gestational period. A silymarin/phospholipid compound containing 29.8% silybin was co administered with EtOH to a separate experimental group. We tested the offspring for laterality preference at age 12 weeks. After testing the rats were sacrificed and their brains perfused for later corpus callosum extraction. Results We observed incomplete development of the splenium in the EtOH-only offspring. Callosal development was complete in all other treatment groups. Rats from the EtOH-only group displayed a left paw preference; whereas control rats were evenly divided between right and left paw preference. Inexplicably both SY groups were largely right paw preferring. Conclusions The addition of SY to the EtOH liquid diet did confer some ameliorative effects upon the developing fetal rat brain.

  13. Size Matters: Cerebral Volume Influences Sex Differences in Neuroanatomy

    Science.gov (United States)

    Towler, Stephen; Welcome, Suzanne; Halderman, Laura K.; Otto, Ron; Eckert, Mark A.; Chiarello, Christine

    2008-01-01

    Biological and behavioral differences between the sexes range from obvious to subtle or nonexistent. Neuroanatomical differences are particularly controversial, perhaps due to the implication that they might account for behavioral differences. In this sample of 200 men and women, large effect sizes (Cohen's d > 0.8) were found for sex differences in total cerebral gray and white matter, cerebellum, and gray matter proportion (women had a higher proportion of gray matter). The only one of these sex differences that survived adjustment for the effect of cerebral volume was gray matter proportion. Individual differences in cerebral volume accounted for 21% of the difference in gray matter proportion, while sex accounted for an additional 4%. The relative size of the corpus callosum was 5% larger in women, but this difference was completely explained by a negative relationship between relative callosal size and cerebral volume. In agreement with Jancke et al., individuals with higher cerebral volume tended to have smaller corpora callosa. There were few sex differences in the size of structures in Broca's and Wernicke's area. We conclude that individual differences in brain volume, in both men and women, account for apparent sex differences in relative size. PMID:18440950

  14. Source to sink transport and regulation by environmental factors

    Directory of Open Access Journals (Sweden)

    Remi eLemoine

    2013-07-01

    Full Text Available Source-to-sink transport of sugar is one of the major determinants of plant growth and relies on the efficient and controlled distribution of sucrose (and some other sugars such as raffinose and polyols across plant organs through the phloem. However, sugar transport through the phloem can be affected by many environmental factors that alter source/sink relationships. In this paper, we summarize current knowledge about the phloem transport mechanisms and review the effects of several abiotic (water and salt stress, mineral deficiency, CO2, light, temperature, air and soil pollutants and biotic (mutualistic and pathogenic microbes, viruses, aphids and parasitic plants factors. Concerning abiotic constraints, alteration of the distribution of sugar among sinks is often reported, with some sinks as roots favoured in case of mineral deficiency. Many of these constraints impair the transport function of the phloem but the exact mechanisms are far from being completely known. Phloem integrity can be disrupted (e.g. by callose deposition and under certain conditions, phloem transport is affected, earlier than photosynthesis. Photosynthesis inhibition could result from the increase in sugar concentration due to phloem transport decrease. Biotic interactions (aphids, fungi, viruses… also affect crop plant productivity. Recent breakthroughs have identified some of the sugar transporters involved in these interactions on the host and pathogen sides. The different data are discussed in relation to the phloem transport pathways. When possible, the link with current knowledge on the pathways at the molecular level will be highlighted.

  15. Morphometric analysis of brain shape in children with nonsyndromic cleft lip and/or palate.

    Science.gov (United States)

    Chollet, Madeleine B; DeLeon, Valerie B; Conrad, Amy L; Nopoulos, Peg

    2014-12-01

    The purpose of this study was to test for differences in brain shape among children with cleft palate only (n = 22), children with cleft lip and palate (n = 35), and controls (n = 39) using Euclidean distance matrix analysis. Sixteen percent of interlandmark distances differed between children with cleft palate only and controls, 10% differed between children with cleft lip and palate and controls, and 10% differed between children with cleft palate only and children with cleft lip and palate. Major differences in brain shape associated with cleft lip and/or palate included posterior expansion of the occipital lobe, reorientation of the cerebellum, heightened callosal midbody, and posterior displacement of the caudate nucleus and thalamus. Differences in brain shape unique to cleft palate only and to cleft lip and palate were also identified. These results expand upon previous volumetric studies on brain morphology in individuals with cleft lip and/or palate and provide additional evidence that the primary defect in cleft lip and/or palate results in both facial and brain dysmorphology. © The Author(s) 2013.

  16. Conscious and unconscious processing of facial expressions: evidence from two split-brain patients.

    Science.gov (United States)

    Prete, Giulia; D'Ascenzo, Stefania; Laeng, Bruno; Fabri, Mara; Foschi, Nicoletta; Tommasi, Luca

    2015-03-01

    We investigated how the brain's hemispheres process explicit and implicit facial expressions in two 'split-brain' patients (one with a complete and one with a partial anterior resection). Photographs of faces expressing positive, negative or neutral emotions were shown either centrally or bilaterally. The task consisted in judging the friendliness of each person in the photographs. Half of the photograph stimuli were 'hybrid faces', that is an amalgamation of filtered images which contained emotional information only in the low range of spatial frequency, blended to a neutral expression of the same individual in the rest of the spatial frequencies. The other half of the images contained unfiltered faces. With the hybrid faces the patients and a matched control group were more influenced in their social judgements by the emotional expression of the face shown in the left visual field (LVF). When the expressions were shown explicitly, that is without filtering, the control group and the partially callosotomized patient based their judgement on the face shown in the LVF, whereas the complete split-brain patient based his ratings mainly on the face presented in the right visual field. We conclude that the processing of implicit emotions does not require the integrity of callosal fibres and can take place within subcortical routes lateralized in the right hemisphere. © 2013 The British Psychological Society.

  17. The Superior Frontal Transsulcal Approach to the Anterior Ventricular System: Exploring the Sulcal and Subcortical Anatomy Using Anatomic Dissections and Diffusion Tensor Imaging Tractography.

    Science.gov (United States)

    Koutsarnakis, Christos; Liakos, Faidon; Kalyvas, Aristotelis V; Skandalakis, Georgios P; Komaitis, Spyros; Christidi, Fotini; Karavasilis, Efstratios; Liouta, Evangelia; Stranjalis, George

    2017-10-01

    To explore the superior frontal sulcus (SFS) morphology, trajectory of the applied surgical corridor, and white matter bundles that are traversed during the superior frontal transsulcal transventricular approach. Twenty normal, adult, formalin-fixed cerebral hemispheres and 2 cadaveric heads were included in the study. The topography, morphology, and dimensions of the SFS were recorded in all specimens. Fourteen hemispheres were investigated through the fiber dissection technique whereas the remaining 6 were explored using coronal cuts. The cadaveric heads were used to perform the superior frontal transsulcal transventricular approach. In addition, 2 healthy volunteers underwent diffusion tensor imaging and tractography reconstruction studies. The SFS was interrupted in 40% of the specimens studied and was always parallel to the interhemispheric fissure. The proximal 5 cm of the SFS (starting from the SFS precentral sulcus meeting point) were found to overlie the anterior ventricular system in all hemispheres. Five discrete white matter layers were identified en route to the anterior ventricular system (i.e., the arcuate fibers, the frontal aslant tract, the external capsule, internal capsule, and the callosal radiations). Diffusion tensor imaging studies confirmed the fiber tract architecture. When feasible, the superior frontal transsulcal transventricular approach offers a safe and effective corridor to the anterior part of the lateral ventricle because it minimizes brain retraction and transgression and offers a wide and straightforward working corridor. Meticulous preoperative planning coupled with a sound microneurosurgical technique are prerequisites to perform the approach successfully. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Silencing of sterol glycosyltransferases modulates the withanolide biosynthesis and leads to compromised basal immunity of Withania somnifera.

    Science.gov (United States)

    Singh, Gaurav; Tiwari, Manish; Singh, Surendra Pratap; Singh, Surendra; Trivedi, Prabodh Kumar; Misra, Pratibha

    2016-05-05

    Sterol glycosyltransferases (SGTs) catalyse transfer of glycon moiety to sterols and their related compounds to produce diverse glyco-conjugates or steryl glycosides with different biological and pharmacological activities. Functional studies of SGTs from Withania somnifera indicated their role in abiotic stresses but details about role under biotic stress are still unknown. Here, we have elucidated the function of SGTs by silencing SGTL1, SGTL2 and SGTL4 in Withania somnifera. Down-regulation of SGTs by artificial miRNAs led to the enhanced accumulation of withanolide A, withaferin A, sitosterol, stigmasterol and decreased content of withanoside V in Virus Induced Gene Silencing (VIGS) lines. This was further correlated with increased expression of WsHMGR, WsDXR, WsFPPS, WsCYP710A1, WsSTE1 and WsDWF5 genes, involved in withanolide biosynthesis. These variations of withanolide concentrations in silenced lines resulted in pathogen susceptibility as compared to control plants. The infection of Alternaria alternata causes increased salicylic acid, callose deposition, superoxide dismutase and H2O2 in aMIR-VIGS lines. The expression of biotic stress related genes, namely, WsPR1, WsDFS, WsSPI and WsPR10 were also enhanced in aMIR-VIGS lines in time dependent manner. Taken together, our observations revealed that a positive feedback regulation of withanolide biosynthesis occurred by silencing of SGTLs which resulted in reduced biotic tolerance.

  19. A T1 and DTI fused 3D corpus callosum analysis in pre- vs. post-season contact sports players

    Science.gov (United States)

    Lao, Yi; Law, Meng; Shi, Jie; Gajawelli, Niharika; Haas, Lauren; Wang, Yalin; Leporé, Natasha

    2015-01-01

    Sports related traumatic brain injury (TBI) is a worldwide public health issue, and damage to the corpus callosum (CC) has been considered as an important indicator of TBI. However, contact sports players suffer repeated hits to the head during the course of a season even in the absence of diagnosed concussion, and less is known about their effect on callosal anatomy. In addition, T1-weighted and diffusion tensor brain magnetic resonance images (DTI) have been analyzed separately, but a joint analysis of both types of data may increase statistical power and give a more complete understanding of anatomical correlates of subclinical concussions in these athletes. Here, for the first time, we fuse T1 surface-based morphometry and a new DTI analysis on 3D surface representations of the CCs into a single statistical analysis on these subjects. Our new combined method successfully increases detection power in detecting differences between pre- vs. post-season contact sports players. Alterations are found in the ventral genu, isthmus, and splenium of CC. Our findings may inform future health assessments in contact sports players. The new method here is also the first truly multimodal diffusion and T1-weighted analysis of the CC, and may be useful to detect anatomical changes in the corpus callosum in other multimodal datasets.

  20. Interference of the Histone Deacetylase Inhibits Pollen Germination and Pollen Tube Growth in Picea wilsonii Mast.

    Directory of Open Access Journals (Sweden)

    Yaning Cui

    Full Text Available Histone deacetylase (HDAC is a crucial component in the regulation of gene expression in various cellular processes in animal and plant cells. HDAC has been reported to play a role in embryogenesis. However, the effect of HDAC on androgamete development remains unclear, especially in gymnosperms. In this study, we used the HDAC inhibitors trichostatin A (TSA and sodium butyrate (NaB to examine the role of HDAC in Picea wilsonii pollen germination and pollen tube elongation. Measurements of the tip-focused Ca2+ gradient revealed that TSA and NaB influenced this gradient. Immunofluorescence showed that actin filaments were disrupted into disorganized fragments. As a result, the vesicle trafficking was disturbed, as determined by FM4-64 labeling. Moreover, the distribution of pectins and callose in cell walls was significantly altered in response to TSA and NaB. Our results suggest that HDAC affects pollen germination and polarized pollen tube growth in Picea wilsonii by affecting the intracellular Ca2+ concentration gradient, actin organization patterns, vesicle trafficking, as well as the deposition and configuration of cell wall components.

  1. Microsurgical and Tractographic Anatomy of the Supplementary Motor Area Complex in Humans.

    Science.gov (United States)

    Bozkurt, Baran; Yagmurlu, Kaan; Middlebrooks, Erik H; Karadag, Ali; Ovalioglu, Talat Cem; Jagadeesan, Bharathi; Sandhu, Gauravjot; Tanriover, Necmettin; Grande, Andrew W

    2016-11-01

    To evaluate the microsurgical anatomy of the fiber tract connections of the supplementary motor area (SMA) and pre-SMA, and examine its potential functional role with reference to clinical trials in the literature. Ten postmortem formalin-fixed human brains (20 sides) and 1 cadaveric head were prepared following Klingler's method. The fiber dissection was performed in a stepwise fashion, from lateral to medial and also from medial to lateral, under an operating microscope, with 3D images captured at each stage. Our findings were supported by in vivo magnetic resonance imaging tractography in 2 healthy subjects. The connections of the SMA complex, composed of the pre-SMA and the SMA proper, are composed of short "U" association fibers and the superior longitudinal fasciculus I, cingulum, claustrocortical fibers, callosal fibers, corticospinal tract, frontal aslant tract, and frontostriatal tract. The claustrocortical fibers may play an important role in the integration of motor, language, and limbic functions of the SMA complex. The frontostriatal tract connects the pre-SMA to the putamen and caudate nucleus, and also forms parts of both the internal capsule and the dorsal external capsule. The SMA complex has numerous connections throughout the cerebrum. An understanding of these connections is important for presurgical planning for lesions in the frontal lobe and helps explain symptoms related to SMA injury. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. De Novo Mutations in the Beta-Tubulin Gene TUBB2A Cause Simplified Gyral Patterning and Infantile-Onset Epilepsy

    Science.gov (United States)

    Cushion, Thomas D.; Paciorkowski, Alex R.; Pilz, Daniela T.; Mullins, Jonathan G.L.; Seltzer, Laurie E.; Marion, Robert W.; Tuttle, Emily; Ghoneim, Dalia; Christian, Susan L.; Chung, Seo-Kyung; Rees, Mark I.; Dobyns, William B.

    2014-01-01

    Tubulins, and microtubule polymers into which they incorporate, play critical mechanical roles in neuronal function during cell proliferation, neuronal migration, and postmigrational development: the three major overlapping events of mammalian cerebral cortex development. A number of neuronally expressed tubulin genes are associated with a spectrum of disorders affecting cerebral cortex formation. Such “tubulinopathies” include lissencephaly/pachygyria, polymicrogyria-like malformations, and simplified gyral patterns, in addition to characteristic extracortical features, such as corpus callosal, basal ganglia, and cerebellar abnormalities. Epilepsy is a common finding in these related disorders. Here we describe two unrelated individuals with infantile-onset epilepsy and abnormalities of brain morphology, harboring de novo variants that affect adjacent amino acids in a beta-tubulin gene TUBB2A. Located in a highly conserved loop, we demonstrate impaired tubulin and microtubule function resulting from each variant in vitro and by using in silico predictive modeling. We propose that the affected functional loop directly associates with the alpha-tubulin-bound guanosine triphosphate (GTP) molecule, impairing the intradimer interface and correct formation of the alpha/beta-tubulin heterodimer. This study associates mutations in TUBB2A with the spectrum of “tubulinopathy” phenotypes. As a consequence, genetic variations affecting all beta-tubulin genes expressed at high levels in the brain (TUBB2B, TUBB3, TUBB, TUBB4A, and TUBB2A) have been linked with malformations of cortical development. PMID:24702957

  3. Expanding the spectrum of human ganglionic eminence region anomalies on fetal magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Righini, Andrea; Parazzini, Cecilia; Izzo, Giana [Children' s Hospital ' ' V. Buzzi' ' , Department of Radiology and Neuroradiology, Milan (Italy); Cesaretti, Claudia [Children' s Hospital ' ' V. Buzzi' ' , Department of Radiology and Neuroradiology, Milan (Italy); Ospedale Maggiore Policlinico, Medical Genetics Unit, Fondazione I.R.C.C.S. Ca' Granda, Milan (Italy); Conte, Giorgio [Children' s Hospital ' ' V. Buzzi' ' , Department of Radiology and Neuroradiology, Milan (Italy); University of Milan, Department of Health Sciences, Milan (Italy); Frassoni, Carolina; Inverardi, Francesca [Fondazione I.R.C.C.S. Istituto Neurologico ' ' C. Besta' ' , Clinical Epileptology and Experimental Neurophysiology Unit, Milan (Italy); Bulfamante, Gaetano; Avagliano, Laura [San Paolo Hospital, Division of Human Pathology, Milan (Italy); Rustico, Mariangela [Children' s Hospital ' ' V. Buzzi' ' , Department of Obstetrics and Gynaecology, Prenatal Diagnosis, Milan (Italy)

    2016-03-15

    Ganglionic eminence (GE) is a transient fetal brain structure that harvests a significant amount of precursors of cortical GABA-ergic interneurons. Prenatal magnetic resonance (MR) imaging features of GE anomalies (i.e., cavitations) have already been reported associated with severe micro-lissencephaly. The purpose of this report was to illustrate the MR imaging features of GE anomalies in conditions other than severe micro-lissencephalies. Among all the fetuses submitted to prenatal MR imaging at our center from 2005 to 2014, we collected eight cases with GE anomalies and only limited associated brain anomalies. The median gestational age at the time of MR imaging was 21 weeks ranging from 19 to 29 weeks. Two senior pediatric neuroradiologists categorized the anomalies of the GE region in two groups: group one showing cavitation in the GE region and group two showing enlarged GE region. For each fetal case, associated cranial anomalies were also reported. Five out of the eight cases were included in group one and three in group two. Besides the GE region abnormality, all eight cases had additional intracranial anomalies, such as mild partial callosal agenesis, vermian hypoplasia and rotation, cerebellar hypoplasia, ventriculomegaly, enlarged subarachnoid spaces, molar tooth malformation. Ultrasound generally detected most of the associated intracranial anomalies, prompting the MR investigation; on the contrary in none of the cases, GE anomalies had been detected by ultrasound. Our observation expands the spectrum of human GE anomalies, demonstrating that these may take place also without associated severe micro-lissencephalies. (orig.)

  4. Neuroanatomical characterization of the cellular and axonal architecture of subcortical band heterotopia in the BXD29-Tlr4lps-2J/J mouse cortex.

    Science.gov (United States)

    Ramos, Raddy L; Toia, Alyssa R; Pasternack, Daniel M; Dotzler, Timothy P; Cuoco, Joshua A; Esposito, Anthony W; Le, Megan M; Parker, Alexander K; Goodman, Jeffrey H; Sarkisian, Matthew R

    2016-11-19

    Subcortical band heterotopia (SBH) are malformations of the human cerebral cortex typically associated with epilepsy and cognitive delay/disability. Rodent models of SBH have demonstrated strong face validity as they are accompanied by both cognitive deficits and spontaneous seizures or reduced seizure threshold. BXD29-Tlr4lps-2J/J recombinant inbred mice display striking bilateral SBH, partial callosal agenesis, morphological changes in subcortical structures of the auditory pathway, and display sensory deficits in behavioral tests (Rosen et al., 2013; Truong et al., 2013, 2015). Surprisingly, these mice show no cognitive deficits and have a higher seizure threshold to chemi-convulsive treatment (Gabel et al., 2013) making them different than other rodent SBH models described previously. In the present report, we perform a detailed characterization of the cellular and axonal constituents of SBH in BXD29-Tlr4lps-2J/J mice and demonstrate that various types of interneurons and glia as well as cortical and subcortical projections are found in SBH. In addition, the length of neuronal cilia was reduced in SBH compared to neurons in the overlying and adjacent normotopic cortex. Finally, we describe additional and novel malformations of the hippocampus and neocortex present in BXD29-Tlr4lps-2J/J mice. Together, our findings in BXD29-Tlr4lps-2J/J mice are discussed in the context of the known neuroanatomy and phenotype of other SBH rodent models. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  5. Scavenging iron: a novel mechanism of plant immunity activation by microbial siderophores.

    Science.gov (United States)

    Aznar, Aude; Chen, Nicolas W G; Rigault, Martine; Riache, Nassima; Joseph, Delphine; Desmaële, Didier; Mouille, Grégory; Boutet, Stéphanie; Soubigou-Taconnat, Ludivine; Renou, Jean-Pierre; Thomine, Sébastien; Expert, Dominique; Dellagi, Alia

    2014-04-01

    Siderophores are specific ferric iron chelators synthesized by virtually all microorganisms in response to iron deficiency. We have previously shown that they promote infection by the phytopathogenic enterobacteria Dickeya dadantii and Erwinia amylovora. Siderophores also have the ability to activate plant immunity. We have used complete Arabidopsis transcriptome microarrays to investigate the global transcriptional modifications in roots and leaves of Arabidopsis (Arabidopsis thaliana) plants after leaf treatment with the siderophore deferrioxamine (DFO). Physiological relevance of these transcriptional modifications was validated experimentally. Immunity and heavy-metal homeostasis were the major processes affected by DFO. These two physiological responses could be activated by a synthetic iron chelator ethylenediamine-di(o-hydroxyphenylacetic) acid, indicating that siderophores eliciting activities rely on their strong iron-chelating capacity. DFO was able to protect Arabidopsis against the pathogenic bacterium Pseudomonas syringae pv tomato DC3000. Siderophore treatment caused local modifications of iron distribution in leaf cells visible by ferrocyanide and diaminobenzidine-H₂O₂ staining. Metal quantifications showed that DFO causes a transient iron and zinc uptake at the root level, which is presumably mediated by the metal transporter iron regulated transporter1 (IRT1). Defense gene expression and callose deposition in response to DFO were compromised in an irt1 mutant. Consistently, plant susceptibility to D. dadantii was increased in the irt1 mutant. Our work shows that iron scavenging is a unique mechanism of immunity activation in plants. It highlights the strong relationship between heavy-metal homeostasis and immunity.

  6. Scavenging Iron: A Novel Mechanism of Plant Immunity Activation by Microbial Siderophores1[C][W

    Science.gov (United States)

    Aznar, Aude; Chen, Nicolas W.G.; Rigault, Martine; Riache, Nassima; Joseph, Delphine; Desmaële, Didier; Mouille, Grégory; Boutet, Stéphanie; Soubigou-Taconnat, Ludivine; Renou, Jean-Pierre; Thomine, Sébastien; Expert, Dominique; Dellagi, Alia

    2014-01-01

    Siderophores are specific ferric iron chelators synthesized by virtually all microorganisms in response to iron deficiency. We have previously shown that they promote infection by the phytopathogenic enterobacteria Dickeya dadantii and Erwinia amylovora. Siderophores also have the ability to activate plant immunity. We have used complete Arabidopsis transcriptome microarrays to investigate the global transcriptional modifications in roots and leaves of Arabidopsis (Arabidopsis thaliana) plants after leaf treatment with the siderophore deferrioxamine (DFO). Physiological relevance of these transcriptional modifications was validated experimentally. Immunity and heavy-metal homeostasis were the major processes affected by DFO. These two physiological responses could be activated by a synthetic iron chelator ethylenediamine-di(o-hydroxyphenylacetic) acid, indicating that siderophores eliciting activities rely on their strong iron-chelating capacity. DFO was able to protect Arabidopsis against the pathogenic bacterium Pseudomonas syringae pv tomato DC3000. Siderophore treatment caused local modifications of iron distribution in leaf cells visible by ferrocyanide and diaminobenzidine-H2O2 staining. Metal quantifications showed that DFO causes a transient iron and zinc uptake at the root level, which is presumably mediated by the metal transporter iron regulated transporter1 (IRT1). Defense gene expression and callose deposition in response to DFO were compromised in an irt1 mutant. Consistently, plant susceptibility to D. dadantii was increased in the irt1 mutant. Our work shows that iron scavenging is a unique mechanism of immunity activation in plants. It highlights the strong relationship between heavy-metal homeostasis and immunity. PMID:24501001

  7. Human motor corpus callosum: topography, somatotopy, and link between microstructure and function.

    Science.gov (United States)

    Wahl, Mathias; Lauterbach-Soon, Birgit; Hattingen, Elke; Jung, Patrick; Singer, Oliver; Volz, Steffen; Klein, Johannes C; Steinmetz, Helmuth; Ziemann, Ulf

    2007-11-07

    The corpus callosum (CC) is the principal white matter fiber bundle connecting neocortical areas of the two hemispheres. Although an object of extensive research, important details about the anatomical and functional organization of the human CC are still largely unknown. Here we focused on the callosal motor fibers (CMFs) that connect the primary motor cortices (M1) of the two hemispheres. Topography and somatotopy of CMFs were explored by using a combined functional magnetic resonance imaging/diffusion tensor imaging fiber-tracking procedure. CMF microstructure was assessed by fractional anisotropy (FA), and CMF functional connectivity between the hand areas of M1 was measured by interhemispheric inhibition using paired-pulse transcranial magnetic stimulation. CMFs mapped onto the posterior body and isthmus of the CC, with hand CMFs running significantly more anteriorly and ventrally than foot CMFs. FA of the hand CMFs but not FA of the foot CMFs correlated linearly with interhemispheric inhibition between the M1 hand areas. Findings demonstrate that CMFs connecting defined body representations of M1 map onto a circumscribed region in the CC in a somatotopically organized manner. The significant and topographically specific positive correlation between FA and interhemispheric inhibition strongly suggests that microstructure can be directly linked to functional connectivity. This provides a novel way of exploring human brain function that may allow prediction of functional connectivity from variability of microstructure in healthy individuals, and potentially, abnormality of functional connectivity in neurological or psychiatric patients.

  8. Paired associative stimulation of left and right human motor cortex shapes interhemispheric motor inhibition based on a Hebbian mechanism.

    Science.gov (United States)

    Rizzo, V; Siebner, H S; Morgante, F; Mastroeni, C; Girlanda, P; Quartarone, A

    2009-04-01

    This study was designed to examine whether corticocortical paired associative stimulation (cc-PAS) can modulate interhemispheric inhibition (IHI) in the human brain. Twelve healthy right-handed volunteers received 90 paired transcranial stimuli to the right and left primary motor hand area (M1(HAND)) at an interstimulus interval (ISI) of 8 ms. Left-to-right cc-PAS (first pulse given to left M1(HAND)) attenuated left-to-right IHI for one hour after cc-PAS. Left-to-right cc-PAS also increased corticospinal excitability in the conditioned right M1(HAND). These effects were not seen in an asymptomatic individual with callosal agenesis. Additional experiments showed no changes in left-to-right IHI or corticospinal excitability when left-to-right cc-PAS was given at an ISI of 1 ms or at multiple ISIs in random order. At the behavioral level, left-to-right cc-PAS speeded responses with the left but not right index finger during a simple reaction time task. Right-to-left cc-PAS (first pulse given to right M1(HAND)) reduced right-to-left IHI without increasing corticospinal excitability in left M1(HAND). These results provide a proof of principle that cc-PAS can induce associative plasticity in connections between the targeted cortical areas. The efficacy of cc-PAS to induce lasting changes in excitability depends on the exact timing of the stimulus pairs suggesting an underlying Hebbian mechanism.

  9. Cerebellar Asymmetry and Cortical Connectivity in Monozygotic Twins with Discordant Handedness.

    Science.gov (United States)

    Rosch, R E; Cowell, P E; Gurd, J M

    2017-10-23

    Handedness differentiates patterns of neural asymmetry and interhemispheric connectivity in cortical systems that underpin manual and language functions. Contemporary models of cerebellar function incorporate complex motor behaviour and higher-order cognition, expanding upon earlier, traditional associations between the cerebellum and motor control. Structural MRI defined cerebellar volume asymmetries and correlations with corpus callosum (CC) size were compared in 19 pairs of adult female monozygotic twins strongly discordant for handedness (MZHd). Volume and asymmetry of cerebellar lobules were obtained using automated parcellation.CC area and regional widths were obtained from midsagittal planimetric measurements. Within the cerebellum and CC, neurofunctional distinctions were drawn between motor and higher-order cognitive systems. Relationships amongst regional cerebellar asymmetry and cortical connectivity (as indicated by CC widths) were investigated. Interactions between hemisphere and handedness in the anterior cerebellum were due to a larger right-greater-than-left hemispheric asymmetry in right-handed (RH) compared to left-handed (LH) twins. In LH twins only, anterior cerebellar lobule volumes (IV, V) for motor control were associated with CC size, particularly in callosal regions associated with motor cortex connectivity. Superior posterior cerebellar lobule volumes (VI, Crus I, Crus II, VIIb) showed no correlation with CC size in either handedness group. These novel results reflected distinct patterns of cerebellar-cortical relationships delineated by specific CC regions and an anterior-posterior cerebellar topographical mapping. Hence, anterior cerebellar asymmetry may contribute to the greater degree of bilateral cortical organisation of frontal motor function in LH individuals.

  10. Bimanual motor deficits in older adults predicted by diffusion tensor imaging metrics of corpus callosum subregions.

    Science.gov (United States)

    Serbruyns, L; Gooijers, J; Caeyenberghs, K; Meesen, R L; Cuypers, K; Sisti, H M; Leemans, A; Swinnen, Stephan P

    2015-01-01

    Age-related changes in the microstructural organization of the corpus callosum (CC) may explain declines in bimanual motor performance associated with normal aging. We used diffusion tensor imaging in young (n = 33) and older (n = 33) adults to investigate the microstructural organization of seven specific CC subregions (prefrontal, premotor, primary motor, primary sensory, parietal, temporal and occipital). A set of bimanual tasks was used to assess various aspects of bimanual motor functioning: the Purdue Pegboard test, simultaneous and alternating finger tapping, a choice reaction time test and a complex visuomotor tracking task. The older adults showed age-related deficits on all measures of bimanual motor performance. Correlation analyses within the older group showed that white matter fractional anisotropy of the CC occipital region was associated with bimanual fine manipulation skills (Purdue Pegboard test), whereas better performance on the other bimanual tasks was related to higher fractional anisotropy in the more anterior premotor, primary motor and primary sensory CC subregions. Such associations were less prominent in the younger group. Our findings suggest that structural alterations of subregional callosal fibers may account for bimanual motor declines in normal aging.

  11. Boron Toxicity Causes Multiple Effects on Malus domestica Pollen Tube Growth.

    Science.gov (United States)

    Fang, Kefeng; Zhang, Weiwei; Xing, Yu; Zhang, Qing; Yang, Liu; Cao, Qingqin; Qin, Ling

    2016-01-01

    Boron is an important micronutrient for plants. However, boron is also toxic to cells at high concentrations, although the mechanism of this toxicity is not known. This study aimed to evaluate the effect of boron toxicity on Malus domestica pollen tube growth and its possible regulatory pathway. Our results showed that a high concentration of boron inhibited pollen germination and tube growth and led to the morphological abnormality of pollen tubes. Fluorescent labeling coupled with a scanning ion-selective electrode technique detected that boron toxicity could decrease [Ca(2+)]c and induce the disappearance of the [Ca(2+)]c gradient, which are critical for pollen tube polar growth. Actin filaments were therefore altered by boron toxicity. Immuno-localization and fluorescence labeling, together with fourier-transform infrared analysis, suggested that boron toxicity influenced the accumulation and distribution of callose, de-esterified pectins, esterified pectins, and arabinogalactan proteins in pollen tubes. All of the above results provide new insights into the regulatory role of boron in pollen tube development. In summary, boron likely plays a structural and regulatory role in relation to [Ca(2+)]c, actin cytoskeleton and cell wall components and thus regulates Malus domestica pollen germination and tube polar growth.

  12. Myosins XI modulate host cellular responses and penetration resistance to fungal pathogens

    Science.gov (United States)

    Yang, Long; Qin, Li; Liu, Guosheng; Peremyslov, Valera V.; Dolja, Valerian V.; Wei, Yangdou

    2014-01-01

    The rapid reorganization and polarization of actin filaments (AFs) toward the pathogen penetration site is one of the earliest cellular responses, yet the regulatory mechanism of AF dynamics is poorly understood. Using live-cell imaging in Arabidopsis, we show that polarization coupled with AF bundling involves precise spatiotemporal control at the site of attempted penetration by the nonadapted barley powdery mildew fungus, Blumeria graminis f. sp. hordei (Bgh). We further show that the Bgh-triggered AF mobility and organelle aggregation are predominately driven by the myosin motor proteins. Inactivation of myosins by pharmacological inhibitors prevents bulk aggregation of organelles and blocks recruitment of lignin-like compounds to the penetration site and deposition of callose and defensive protein, PENETRATION 1 (PEN1) into the apoplastic papillae, resulting in attenuation of penetration resistance. Using gene knockout analysis, we demonstrate that highly expressed myosins XI, especially myosin XI-K, are the primary contributors to cell wall-mediated penetration resistance. Moreover, the quadruple myosin knockout mutant xi-1 xi-2 xi-i xi-k displays impaired trafficking pathway responsible for the accumulation of PEN1 at the cell periphery. Strikingly, this mutant shows not only increased penetration rate but also enhanced overall disease susceptibility to both adapted and nonadapted fungal pathogens. Our findings establish myosins XI as key regulators of plant antifungal immunity. PMID:25201952

  13. Maturation of Corpus Callosum Anterior Midbody Is Associated with Neonatal Motor Function in Eight Preterm-Born Infants

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    Mathew, Preethi; Pannek, Kerstin; D'Acunto, M. Giulia; Guzzetta, Andrea; Rose, Stephen E.; Colditz, Paul B.; Finnigan, Simon

    2013-01-01

    Background. The etiology of motor impairments in preterm infants is multifactorial and incompletely understood. Whether corpus callosum development is related to impaired motor function is unclear. Potential associations between motor-related measures and diffusion tensor imaging (DTI) of the corpus callosum in preterm infants were explored. Methods. Eight very preterm infants (gestational age of 28–32 weeks) underwent the Hammersmith neonatal neurological examination and DTI assessments at gestational age of 42 weeks. The total Hammersmith score and a motor-specific score (sum of Hammersmith motor subcategories) were calculated. Six corpus callosum regions of interest were defined on the mid-sagittal DTI slice—genu, rostral body, anterior midbody, posterior midbody, isthmus, and splenium. The fractional anisotropy (FA) and mean diffusivity (MD) of these regions were computed, and correlations between these and Hammersmith measures were sought. Results. Anterior midbody FA measures correlated positively with total Hammersmith (rho = 0.929, P = 0.001) and motor-specific scores (rho = 0.857, P = 0.007). Total Hammersmith scores also negatively correlated with anterior midbody MD measures (rho = −0.714, P = 0.047). Discussion. These results suggest the integrity of corpus callosum axons, particularly anterior midbody axons, is important in mediating neurological functions. Greater callosal maturation was associated with greater motor function. Corpus callosum DTI may prove to be a valuable screening or prognostic marker. PMID:23509639

  14. Maturation of Corpus Callosum Anterior Midbody Is Associated with Neonatal Motor Function in Eight Preterm-Born Infants

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    Preethi Mathew

    2013-01-01

    Full Text Available Background. The etiology of motor impairments in preterm infants is multifactorial and incompletely understood. Whether corpus callosum development is related to impaired motor function is unclear. Potential associations between motor-related measures and diffusion tensor imaging (DTI of the corpus callosum in preterm infants were explored. Methods. Eight very preterm infants (gestational age of 28–32 weeks underwent the Hammersmith neonatal neurological examination and DTI assessments at gestational age of 42 weeks. The total Hammersmith score and a motor-specific score (sum of Hammersmith motor subcategories were calculated. Six corpus callosum regions of interest were defined on the mid-sagittal DTI slice—genu, rostral body, anterior midbody, posterior midbody, isthmus, and splenium. The fractional anisotropy (FA and mean diffusivity (MD of these regions were computed, and correlations between these and Hammersmith measures were sought. Results. Anterior midbody FA measures correlated positively with total Hammersmith (rho =0.929, P=0.001 and motor-specific scores (rho =0.857, P=0.007. Total Hammersmith scores also negatively correlated with anterior midbody MD measures (rho =−0.714, P=0.047. Discussion. These results suggest the integrity of corpus callosum axons, particularly anterior midbody axons, is important in mediating neurological functions. Greater callosal maturation was associated with greater motor function. Corpus callosum DTI may prove to be a valuable screening or prognostic marker.

  15. De Novo Transcriptome Sequencing of Olea europaea L. to Identify Genes Involved in the Development of the Pollen Tube

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    Domenico Iaria

    2016-01-01

    Full Text Available In olive (Olea europaea L., the processes controlling self-incompatibility are still unclear and the molecular basis underlying this process are still not fully characterized. In order to determine compatibility relationships, using next-generation sequencing techniques and a de novo transcriptome assembly strategy, we show that pollen tubes from different olive plants, grown in vitro in a medium containing its own pistil and in combination pollen/pistil from self-sterile and self-fertile cultivars, have a distinct gene expression profile and many of the differentially expressed sequences between the samples fall within gene families involved in the development of the pollen tube, such as lipase, carboxylesterase, pectinesterase, pectin methylesterase, and callose synthase. Moreover, different genes involved in signal transduction, transcription, and growth are overrepresented. The analysis also allowed us to identify members in actin and actin depolymerization factor and fibrin gene family and member of the Ca2+ binding gene family related to the development and polarization of pollen apical tip. The whole transcriptomic analysis, through the identification of the differentially expressed transcripts set and an extended functional annotation analysis, will lead to a better understanding of the mechanisms of pollen germination and pollen tube growth in the olive.

  16. Cell Wall Composition, Biosynthesis and Remodeling during Pollen Tube Growth.

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    Mollet, Jean-Claude; Leroux, Christelle; Dardelle, Flavien; Lehner, Arnaud

    2013-03-07

    The pollen tube is a fast tip-growing cell carrying the two sperm cells to the ovule allowing the double fertilization process and seed setting. To succeed in this process, the spatial and temporal controls of pollen tube growth within the female organ are critical. It requires a massive cell wall deposition to promote fast pollen tube elongation and a tight control of the cell wall remodeling to modify the mechanical properties. In addition, during its journey, the pollen tube interacts with the pistil, which plays key roles in pollen tube nutrition, guidance and in the rejection of the self-incompatible pollen. This review focuses on our current knowledge in the biochemistry and localization of the main cell wall polymers including pectin, hemicellulose, cellulose and callose from several pollen tube species. Moreover, based on transcriptomic data and functional genomic studies, the possible enzymes involved in the cell wall remodeling during pollen tube growth and their impact on the cell wall mechanics are also described. Finally, mutant analyses have permitted to gain insight in the function of several genes involved in the pollen tube cell wall biosynthesis and their roles in pollen tube growth are further discussed.

  17. Cognitive and behavioral functioning in Coffin-Siris syndrome and epilepsy: a case presentation.

    Science.gov (United States)

    Bender, H Allison; Zaroff, Charles M; Karantzoulis, Stella; Nakhutina, Luba; MacAllister, William S; Luciano, Daniel

    2011-01-01

    The authors characterized the cognitive, adaptive, and behavioral sequelae of Coffin-Siris (CS) syndrome and epilepsy in a 7.5-year-old child. Little is known about the early neurobehavioral presentation of CS. Clinical features consistent with this genetic anomaly include underdeveloped tips and nails of the fifth fingers, extended infranasal depression, and craniofacial abnormalities. MRI findings often reveal callosal agenesis. The authors conducted a neuropsychological evaluation and obtained parental ratings of behavioral and adaptive functioning. Attentional abilities were limited. As assessed by the Mullen Scales of Early Learning, receptive language abilities (age equivalent [AE]: 3-3) were relatively stronger than expressive skills (AE: 1-4). Adaptive functioning was low across all domains (Vineland Adaptive Behavior Composite AE: 1-9). On the Behavior Assessment for Children (BASC-2), social skills dysfunction, stereotyped and self-stimulatory behaviors, restricted interests, ritualistic play, and inappropriate object usage were noted. No significant mood disturbances were endorsed. Study findings indicate a diffuse pattern of neurobehavioral deficits in a child with CS and epilepsy. Further clinical assessment and research should include multidimensional assessment techniques, including evaluation of adaptive behavior, in an effort to capture the full range developmental sequelae in children with CS.

  18. Unravelling early events in the Taphrina deformans-Prunus persica interaction: an insight into the differential responses in resistant and susceptible genotypes.

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    Svetaz, Laura A; Bustamante, Claudia A; Goldy, Camila; Rivero, Nery; Müller, Gabriela L; Valentini, Gabriel H; Fernie, Alisdair R; Drincovich, María F; Lara, María V

    2017-08-01

    Leaf peach curl is a devastating disease affecting leaves, flowers and fruits, caused by the dimorphic fungus Taphrina deformans. To gain insight into the mechanisms of fungus pathogenesis and plant responses, leaves of a resistant and two susceptible Prunus persica genotypes were inoculated with blastospores (yeast), and the infection was monitored during 120 h post inoculation (h.p.i.). Fungal dimorphism to the filamentous form and induction of reactive oxygen species (ROS), callose synthesis, cell death and defence compound production were observed independently of the genotype. Fungal load significantly decreased after 120 h.p.i. in the resistant genotype, while the pathogen tended to grow in the susceptible genotypes. Metabolic profiling revealed a biphasic re-programming of plant tissue in susceptible genotypes, with an initial stage co-incident with the yeast form of the fungus and a second when the hypha is developed. Transcriptional analysis of PRs and plant hormone-related genes indicated that pathogenesis-related (PR) proteins are involved in P. persica defence responses against T. deformans and that salicylic acid is induced in the resistant genotype. Conducted experiments allowed the elucidation of common and differential responses in susceptible versus resistant genotypes and thus allow us to construct a picture of early events during T. deformans infection. © 2017 John Wiley & Sons Ltd.

  19. Manipulation of the Xanthophyll Cycle Increases Plant Susceptibility to Sclerotinia sclerotiorum.

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    Jun Zhou

    2015-05-01

    Full Text Available The xanthophyll cycle is involved in dissipating excess light energy to protect the photosynthetic apparatus in a process commonly assessed from non-photochemical quenching (NPQ of chlorophyll fluorescence. Here, it is shown that the xanthophyll cycle is modulated by the necrotrophic pathogen Sclerotinia sclerotiorum at the early stage of infection. Incubation of Sclerotinia led to a localized increase in NPQ even at low light intensity. Further studies showed that this abnormal change in NPQ was closely correlated with a decreased pH caused by Sclerotinia-secreted oxalate, which might decrease the ATP synthase activity and lead to a deepening of thylakoid lumen acidification under continuous illumination. Furthermore, suppression (with dithiothreitol or a defect (in the npq1-2 mutant of violaxanthin de-epoxidase (VDE abolished the Sclerotinia-induced NPQ increase. HPLC analysis showed that the Sclerotinia-inoculated tissue accumulated substantial quantities of zeaxanthin at the expense of violaxanthin, with a corresponding decrease in neoxanthin content. Immunoassays revealed that the decrease in these xanthophyll precursors reduced de novo abscisic acid (ABA biosynthesis and apparently weakened tissue defense responses, including ROS induction and callose deposition, resulting in enhanced plant susceptibility to Sclerotinia. We thus propose that Sclerotinia antagonizes ABA biosynthesis to suppress host defense by manipulating the xanthophyll cycle in early pathogenesis. These findings provide a model of how photoprotective metabolites integrate into the defense responses, and expand the current knowledge of early plant-Sclerotinia interactions at infection sites.

  20. Morphological heterogeneity of layer VI neurons in mouse barrel cortex.

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    Chen, Chia-Chien; Abrams, Svetlana; Pinhas, Alex; Brumberg, Joshua C

    2009-02-20

    Understanding the basic neuronal building blocks of the neocortex is a necessary first step toward comprehending the composition of cortical circuits. Neocortical layer VI is the most morphologically diverse layer and plays a pivotal role in gating information to the cortex via its feedback connection to the thalamus and other ipsilateral and callosal corticocortical connections. The heterogeneity of function within this layer is presumably linked to its varied morphological composition. However, so far, very few studies have attempted to define cell classes in this layer using unbiased quantitative methodologies. Utilizing the Golgi staining technique along with the Neurolucida software, we recontructed 222 cortical neurons from layer VI of mouse barrel cortex. Morphological analyses were performed by quantifying somatic and dendritic parameters, and, by using principal component and cluster analyses, we quantitatively categorized neurons into six distinct morphological groups. Additional systematic replication on a separate population of neurons yielded similar results, demonstrating the consistency and reliability of our categorization methodology. Subsequent post hoc analyses of dendritic parameters supported our neuronal classification scheme. Characterizing neuronal elements with unbiased quantitative techniques provides a framework for better understanding structure-function relationships within neocortical circuits in general.

  1. Communicative deficits in agenesis of the corpus callosum: nonliteral language and affective prosody.

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    Paul, Lynn K; Van Lancker-Sidtis, Diana; Schieffer, Beatrix; Dietrich, Rosalind; Brown, Warren S

    2003-05-01

    While some individuals with agenesis of the corpus callosum can perform normally on standardized intelligence tests, clinical observations suggest that they nevertheless have deficits in the domains of fluid and social intelligence. Particularly important for social competence is adequate understanding and use of paralinguistic information. This study examined the impact of callosal absence on the processing of pragmatic and paralinguistic information. Young adult males with agenesis of the corpus callosum (ACC) were evaluated in the areas of nonliteral language comprehension, proverb recognition and interpretation, and perception of affective prosody. Ten ACC individuals with normal Wechsler IQ were compared to 14 sex, age, and IQ matched normal controls. The Formulaic and Novel Language Comprehension Test (FANL-C), Gorham Proverbs Test, and LA Prosody Test were administered. ACC subjects exhibited significant impairment on the nonliteral items of the FANL-C, but no significant difference from controls in comprehension of literal items. ACC subjects also exhibited significant deficits in both self-generated interpretation and recognition of proverb meaning, and in recognition of affective prosody. These results demonstrate that normally intelligent individuals with ACC are impaired in the understanding of nonliteral language and emotional-prosodic cues that are important in social communication. In all three tests, the performance of individuals with ACC was similar to patients with right hemisphere brain damage. Thus, persons with ACC appear to lack interhemispheric integration of critical aspects of language processed by the right hemisphere.

  2. Age-related signal intensity changes in the corpus callosum: assessment with three orthogonal FLAIR images

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    Yamamoto, Akira; Miki, Yukio; Kanagaki, Mitsunori; Takahashi, Takahiro; Fushimi, Yasutaka; Haque, Tabassum Laz; Togashi, Kaori [Kyoto University, Department of Nuclear Medicine and Diagnostic Imaging, Graduate School of Medicine, Kyoto (Japan); Tomimoto, Hidekazu [Kyoto University, Department of Neurology, Graduate School of Medicine, Kyoto (Japan); Konishi, Junya [Kobe University, Department of Radiology, Graduate School of Medicine, Kobe, Hyogo (Japan)

    2005-11-01

    The presence of age-related hyperintensities of the corpus callosum has not been thoroughly evaluated. Fifty-two patients of 50 years of age or older (mean, 71 years; range, 50-87 years) were included in this study. Fluid-attenuated inversion recovery images were obtained in three orthogonal planes. Periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs) were graded according to Fazekas' rating scale. Correlations between the presence of hyperintensities in the corpus callosum and age, and the grade of PVH and DWMH were statistically analyzed. PVH was categorized as grade 0 (n=4), grade 1 (n=28), grade 2 (n=10), or grade 3 (n=10). DWMH was categorized as grade 0 (n=4), grade 1 (n=25), grade 2 (n=8), or grade 3 (n=15). Hyperintensity was considered present in the corpus callosum in 31 of the 52 patients (60%). In these 31 patients, PVH was categorized as grade 1 (n=16), grade 2 (n=7), or grade 3 (n=8), while DWMH was categorized as grade 0 (n=1), grade 1 (n=10), grade 2 (n=7), or grade 3 (n=13). The presence of callosal hyperintensities was significantly correlated with age (p=0.001), and with PVH (p=0.04) and DWMH grades (p=0.004). Hyperintensities may be present in the corpus callosum with aging, and are correlated with PVH and DWMH. (orig.)

  3. Loss of Necrotic Spotted Lesions 1 associates with cell death and defense responses in Arabidopsis thaliana.

    Science.gov (United States)

    Noutoshi, Yoshiteru; Kuromori, Takashi; Wada, Takuji; Hirayama, Takashi; Kamiya, Asako; Imura, Yuko; Yasuda, Michiko; Nakashita, Hideo; Shirasu, Ken; Shinozaki, Kazuo

    2006-09-01

    We isolated a lesion mimic mutant, necrotic spotted lesions 1 (nsl1), from Ds-tagged Arabidopsis thaliana accession No-0. The nsl1 mutant exhibits a growth retardation phenotype and develops spotted necrotic lesions on its rosette and cauline leaves. These phenotypes occur in the absence of pathogens indicating that nsl1 mutants may constitutively express defense responses. Consistent with this idea, nsl1 accumulates high levels of callose and autofluorescent phenolic compounds localized to the necrotic lesions. Furthermore RNA gel blot analysis revealed that genes associated with disease resistance activation are upregulated in the nsl1 mutants and these plants contain elevated levels of salicylic acid (SA). Crossing nsl1 with an SA deficient mutant, eds16-1, revealed that the nsl1 lesions and growth retardation are dependent upon SA. The nsl1 phenotypes are not suppressed under either the rar1-10 or sgt1b-1 genetic background. NSL1 encodes a novel 612aa protein which contains a membrane-attack complex/perforin (MACPF) domain, which is conserved in bacteria, fungi, mammals and plants. The possible modes of action of NSL1 protein in negative regulation of cell death programs and defense responses are discussed.

  4. Layered basal defenses underlie non-host resistance of Arabidopsis to Pseudomonas syringae pv. phaseolicola.

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    Ham, Jong Hyun; Kim, Min Gab; Lee, Sang Yeol; Mackey, David

    2007-08-01

    Arabidopsis is a non-host for Pseudomonas syringae pv. phaseolicola NPS3121 (Pph), a bacterial pathogen of bean. Pph does not induce a hypersensitive response in Arabidopsis. Here we show that Arabidopsis instead resists Pph with multi-layered basal defense. Our approach was: (i) to identify defense readouts induced by Pph; (ii) to determine whether mutations in known Arabidopsis defense genes disrupt Pph-induced defense signaling; (iii) to determine whether heterologous type III effectors from pathogens of Arabidopsis suppress Pph-induced defense signaling, and (iv) to ascertain how basal defenses contribute to resistance against Pph by individually or multiply disrupting defense signaling pathways with mutations and heterologous type III effectors. We demonstrate that Pph elicits a minimum of three basal defense-signaling pathways in Arabidopsis. These pathways have unique readouts, including PR-1 protein accumulation and morphologically distinct types of callose deposition. Further, they require distinct defense genes, including PMR4, RAR1, SID2, NPR1, and PAD4. Finally, they are suppressed differentially by heterologous type III effectors, including AvrRpm1 and HopM1. Pph growth is enhanced only when multiple defense pathways are disrupted. For example, mutation of NPR1 or SID2 combined with the action of AvrRpm1 and HopM1 renders Arabidopsis highly susceptible to Pph. Thus, non-host resistance of Arabidopsis to Pph is based on multiple, individually effective layers of basal defense.

  5. Priming of plant resistance by natural compounds. Hexanoic acid as a model

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    Paz eAranega Bou

    2014-10-01

    Full Text Available Some alternative control strategies of currently emerging plant diseases are based on the use of resistance inducers. This review highlights the recent advances made in the characterization of natural compounds that induce resistance by a priming mechanism. These include vitamins, chitosans, oligogalacturonides, volatile organic compounds, azelaic and pipecolic acid, among others. Overall, other than providing novel disease control strategies that meet environmental regulations, natural priming agents are valuable tools to help unravel the complex mechanisms underlying the induced resistance phenomenon. The data presented in this review reflect the novel contributions made from studying these natural plant inducers, with special emphasis placed on hexanoic acid (Hx, proposed herein as a model tool for this research field. Hx is a potent natural priming agent of proven efficiency in a wide range of host plants and pathogens. It can early activate broad-spectrum defenses by inducing callose deposition and the SA and JA pathways. Later it can prime pathogen-specific responses according to the pathogen’s lifestyle. Interestingly, Hx primes redox-related genes to produce an anti-oxidant protective effect, which might be critical for limiting the infection of necrotrophs. Our Hx-induced resistance (Hx-IR findings also strongly suggest that it is an attractive tool for the molecular characterization of the plant alarmed state, with the added advantage of it being a natural compound.

  6. Single-shot T1 mapping of the corpus callosum: A rapid characterization of fiber bundle anatomy

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    Sabine eHofer

    2015-05-01

    Full Text Available Using diffusion-tensor MRI and fiber tractography the topographic organization of the corpus callosum (CC has been described to comprise 5 segments with fibers projecting into prefrontal (I, premotor and supplementary motor (II, primary motor (III, and primary sensory areas (IV, as well as into parietal, temporal, and occipital cortical areas (V. In order to more rapidly characterize the underlying anatomy of these segments, this study used a novel single-shot T1 mapping method to quantitatively determine T1 relaxation times in the human CC. A region-of-interest analysis revealed a tendency for the lowest T1 relaxation times in the genu and the highest T1 relaxation times in the somatomotor region of the CC. This observation separates regions dominated by myelinated fibers with large diameters (somatomotor area from densely packed smaller axonal bundles (genu with less myelin. The results indicate that characteristic T1 relaxation times in callosal profiles provide an additional means to monitor differences in fiber anatomy, fiber density, and gray matter in respective neocortical areas. In conclusion, rapid T1 mapping allows for a characterization of the axonal architecture in an individual CC in less than 10 s. The approach emerges as a valuable means for studying neocortical brain anatomy with possible implications for the diagnosis of neurodegenerative processes.

  7. Refractory High Intracranial Pressure following Intraventricular Hemorrhage due to Moyamoya Disease in a Pregnant Caucasian Woman

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    Virginie Montiel

    2009-02-01

    Full Text Available Intraventricular hemorrhage during pregnancy is usually followed by a poor recovery. When caused by moyamoya disease, ischemic or hemorrhagic episodes may complicate the management of high intracranial pressure. A 26-year-old Caucasian woman presented with generalized seizures and a Glasgow Coma Score (GCS of 3 during the 36th week of pregnancy. The fetus was delivered by caesarean section. The brain CT in the mother revealed bilateral intraventricular hemorrhage, a callosal hematoma, hydrocephalus and right frontal ischemia. Refractory high intracranial pressure developed and required bilateral ventricular drainage and intensive care treatment with barbiturates and hypothermia. Magnetic resonance imaging and cerebral angiography revealed a moyamoya syndrome with rupture of the abnormal collateral vascular network as the cause of the hemorrhage. Intracranial pressure could only be controlled after the surgical removal of the clots after a large opening of the right ventricle. Despite an initially low GCS, this patient made a good functional recovery at one year follow-up. Management of refractory high intracranial pressure following moyamoya related intraventricular bleeding should require optimal removal of ventricular clots and appropriate control of cerebral hemodynamics to avoid ischemic or hemorrhagic complications.

  8. Attachment, penetration and early host defense mechanisms during the infection of filamentous brown algae by Eurychasma dicksonii.

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    Tsirigoti, Amerssa; Beakes, Gordon W; Hervé, Cécile; Gachon, Claire M M; Katsaros, Christos

    2015-05-01

    Eurychasma dicksonii is one of the most common and widespread marine pathogens and attacks a broad spectrum of more than 45 brown algal species. The present study focuses on the mechanism used by the pathogen to attach on the host cell wall and force its way into algal cells. Ultrastructural examination revealed a needle-like structure which develops within the attached spore and extends along its main axis. Particular cell wall modifications are present at the basal part of the spore (adhesorium pad) and guide the needle-like tool to penetrate perpendicularly the host cell wall. The unique injection mechanism is shared with Haptoglossa species which suggests that this is an important characteristic of early diverging oomycetes. Furthermore, the encystment and adhesion mechanism of E. dicksonii shows significant similarities with other oomycetes, some of which are plant pathogens. Staining and immunolabelling techniques showed the deposition of β-1,3-glucans on the host cell wall at the pathogen penetration site, a strategy similar to physical responses previously described only in infected plant cells. It is assumed that the host defense in terms of callose-like deposition is an ancient response to infection.

  9. The Distribution Features of Polysaccharides and Lipids in the Development of Tomato Anthers

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    Zhu Yun

    2015-07-01

    Full Text Available The regulation of nutrient transportation and transformation in developing anthers is very complex. We analyzed the distribution and features of polysaccharides and lipids in the developing anthers of tomatoes using histochemical methods. Some starches appeared in the connective somatic tissue of anthers during the sporogenous cell stage. Before meiosis of the microspore mother cell, a thick polysaccharide callose wall was formed, accompanied by a reduction in the connective tissue starches. During the tetrad stage after meiosis, the polysaccharide material in the anther did not change. At the early microspore stage, the starches in the connective cells again increased, and polysaccharide material appeared in the partial intine of pollen. At the late microspore stage, a large vacuole formed that did not contain lipids or starches, and only the pollen wall contained red polysaccharides. At this stage, the connective somatic cell starch amounts decreased, and the tapetal cells changed shape and degenerated. After microspore division, abundant lipids appeared in the bicellular pollen, and starches accumulated following pollen development. As the anthers matured, many lipids and some starches accumulated in the epidermal cells. Nutrient metabolism within the tomato pollen characteristically accumulated lipids first and then starches, while the mature pollen accumulated starches and lipids simultaneously. This characteristic pattern of nutrient metabolism in tomato pollen shows species specificity among plants.

  10. Ectopic expression of a Ve homolog VvVe gene from Vitis vinifera enhances defense response to Verticillium dahliae infection in tobacco.

    Science.gov (United States)

    Tang, Juan; Lin, Jing; Yang, Yuwen; Chen, Tianzi; Ling, Xitie; Zhang, Baolong; Chang, Youhong

    2016-01-15

    Verticillium wilt is a soil borne disease that can cause devastating losses to the production of many economically important crops. A Ve1 homologous gene responding to Verticillium dahliae infection was identified in Vitis vinifera cv. "HeiFeng" by semi-quantitative reverse transcription polymerase chain reaction and was designated as VvVe. The overexpression of VvVe in transgenic Nicotiana benthamiana plants significantly enhanced the resistance to isolate V991 of V. dahliae when compared with the wild type plants. The expressions of defense-related genes including the salicylic acid regulated gene pathogen-related 1 (PR1) but not PR2, the ethylene- and jasmonic acid-regulated genes ethylene response factor 1 (ERF1) and lipoxygenase (LOX) were significantly increased due to over expression of VvVe. And greater accumulation of active oxygen, callose and phenylalanine-ammonia lyase were observed in the leaves of transgenic VvVe tobacco plants than the wild type when under infection by V. dahliae. Moreover, the hypersensitive response mimicking cell death was exclusively occurred in the transgenic VvVe tobacco plants but not in the wild type. Taken together, the VvVe gene is a Ve1 like gene which involves in the signal cascade of salicylic acid, jasmonate, and ethylene defense pathways and enhances defense response to V. dahliae infection in the transgenic tobacco. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Acute disseminated encephalomyelitis complicating dengue infection with neuroimaging mimicking multiple sclerosis: A report of two cases.

    Science.gov (United States)

    Viswanathan, S; Botross, N; Rusli, B N; Riad, A

    2016-11-01

    Acute disseminated encephalomyelitis (ADEM) complicating dengue infection is still exceedingly rare even in endemic countries such as Malaysia. Here we report two such cases, the first in an elderly female patient and the second in a young man. Both presented with encephalopathy, brainstem involvement and worsening upper and lower limb weakness. Initial magnetic resonance imaging (MRI) of the brain was normal in the first case. Serum for dengue Ig M and NS-1 was positive in both cases. Cerebrospinal fluid (CSF) showed pleocytosis in both with Dengue IgM and NS-1 positive in the second case but not done in the first. MRI brain showed changes of perpendicular subcortical palisading white matter, callosal and brainstem disease mimicking multiple sclerosis (MS) in both patients though in the former case there was a lag between the onset of clinical symptoms and MRI changes which was only clarified on reimaging. The temporal evolution and duration of the clinical symptoms, CSF changes and neuroimaging were more suggestive of Dengue ADEM rather than an encephalitis though initially the first case began as dengue encephalitis. Furthermore in dengue encephalitis neuroimaging is usually normal or rarely edema, haemorrhage, brainstem, thalamic or focal lesions are seen. Therefore, early recognition of ADEM as a sequelae of dengue infection with neuroimaging mimicking MS and repeat imaging helped in identifying these two cases. Treatment with intravenous steroids followed by maintenance oral steroids produced good outcome in both patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. A novel interhemispheric interaction: modulation of neuronal cooperativity in the visual areas.

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    Cristian Carmeli

    Full Text Available BACKGROUND: The cortical representation of the visual field is split along the vertical midline, with the left and the right hemi-fields projecting to separate hemispheres. Connections between the visual areas of the two hemispheres are abundant near the representation of the visual midline. It was suggested that they re-establish the functional continuity of the visual field by controlling the dynamics of the responses in the two hemispheres. METHODS/PRINCIPAL FINDINGS: To understand if and how the interactions between the two hemispheres participate in processing visual stimuli, the synchronization of responses to identical or different moving gratings in the two hemi-fields were studied in anesthetized ferrets. The responses were recorded by multiple electrodes in the primary visual areas and the synchronization of local field potentials across the electrodes were analyzed with a recent method derived from dynamical system theory. Inactivating the visual areas of one hemisphere modulated the synchronization of the stimulus-driven activity in the other hemisphere. The modulation was stimulus-specific and was consistent with the fine morphology of callosal axons in particular with the spatio-temporal pattern of activity that axonal geometry can generate. CONCLUSIONS/SIGNIFICANCE: These findings describe a new kind of interaction between the cerebral hemispheres and highlight the role of axonal geometry in modulating aspects of cortical dynamics responsible for stimulus detection and/or categorization.

  13. 2, 6-dichlorobenzonitrile Causes Multiple Effects on Pollen Tube Growth beyond Altering Cellulose Synthesis in Pinus bungeana Zucc

    Science.gov (United States)

    Hao, Huaiqing; Chen, Tong; Fan, Lusheng; Li, Ruili; Wang, Xiaohua

    2013-01-01

    Cellulose is an important component of cell wall, yet its location and function in pollen tubes remain speculative. In this paper, we studied the role of cellulose synthesis in pollen tube elongation in Pinus bungeana Zucc. by using the specific inhibitor, 2, 6-dichlorobenzonitrile (DCB). In the presence of DCB, the growth rate and morphology of pollen tubes were distinctly changed. The organization of cytoskeleton and vesicle trafficking were also disturbed. Ultrastructure of pollen tubes treated with DCB was characterized by the loose tube wall and damaged organelles. DCB treatment induced distinct changes in tube wall components. Fluorescence labeling results showed that callose, and acidic pectin accumulated in the tip regions, whereas there was less cellulose when treated with DCB. These results were confirmed by FTIR microspectroscopic analysis. In summary, our findings showed that inhibition of cellulose synthesis by DCB affected the organization of cytoskeleton and vesicle trafficking in pollen tubes, and induced changes in the tube wall chemical composition in a dose-dependent manner. These results confirm that cellulose is involved in the establishment of growth direction of pollen tubes, and plays important role in the cell wall construction during pollen tube development despite its lower quantity. PMID:24146903

  14. Bird-like anatomy, posture, and behavior revealed by an early jurassic theropod dinosaur resting trace

    Science.gov (United States)

    Milner, A.R.C.; Harris, J.D.; Lockley, M.G.; Kirkland, J.I.; Matthews, N.A.

    2009-01-01

    Background: Fossil tracks made by non-avian theropod dinosaurs commonly reflect the habitual bipedal stance retained in living birds. Only rarely-captured behaviors, such as crouching, might create impressions made by the hands. Such tracks provide valuable information concerning the often poorly understood functional morphology of the early theropod forelimb. Methodology/Principal Findings: Here we describe a well-preserved theropod trackway in a Lower Jurassic (???198 millionyear- old) lacustrine beach sandstone in the Whitmore Point Member of the Moenave Formation in southwestern Utah. The trackway consists of prints of typical morphology, intermittent tail drags and, unusually, traces made by the animal resting on the substrate in a posture very similar to modern birds. The resting trace includes symmetrical pes impressions and well-defined impressions made by both hands, the tail, and the ischial callosity. Conclusions/Significance: The manus impressions corroborate that early theropods, like later birds, held their palms facing medially, in contrast to manus prints previously attributed to theropods that have forward-pointing digits. Both the symmetrical resting posture and the medially-facing palms therefore evolved by the Early Jurassic, much earlier in the theropod lineage than previously recognized, and may characterize all theropods.

  15. Bird-like anatomy, posture, and behavior revealed by an early jurassic theropod dinosaur resting trace.

    Directory of Open Access Journals (Sweden)

    Andrew R C Milner

    Full Text Available BACKGROUND: Fossil tracks made by non-avian theropod dinosaurs commonly reflect the habitual bipedal stance retained in living birds. Only rarely-captured behaviors, such as crouching, might create impressions made by the hands. Such tracks provide valuable information concerning the often poorly understood functional morphology of the early theropod forelimb. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a well-preserved theropod trackway in a Lower Jurassic ( approximately 198 million-year-old lacustrine beach sandstone in the Whitmore Point Member of the Moenave Formation in southwestern Utah. The trackway consists of prints of typical morphology, intermittent tail drags and, unusually, traces made by the animal resting on the substrate in a posture very similar to modern birds. The resting trace includes symmetrical pes impressions and well-defined impressions made by both hands, the tail, and the ischial callosity. CONCLUSIONS/SIGNIFICANCE: The manus impressions corroborate that early theropods, like later birds, held their palms facing medially, in contrast to manus prints previously attributed to theropods that have forward-pointing digits. Both the symmetrical resting posture and the medially-facing palms therefore evolved by the Early Jurassic, much earlier in the theropod lineage than previously recognized, and may characterize all theropods.

  16. Bird-like anatomy, posture, and behavior revealed by an early jurassic theropod dinosaur resting trace.

    Science.gov (United States)

    Milner, Andrew R C; Harris, Jerald D; Lockley, Martin G; Kirkland, James I; Matthews, Neffra A

    2009-01-01

    Fossil tracks made by non-avian theropod dinosaurs commonly reflect the habitual bipedal stance retained in living birds. Only rarely-captured behaviors, such as crouching, might create impressions made by the hands. Such tracks provide valuable information concerning the often poorly understood functional morphology of the early theropod forelimb. Here we describe a well-preserved theropod trackway in a Lower Jurassic ( approximately 198 million-year-old) lacustrine beach sandstone in the Whitmore Point Member of the Moenave Formation in southwestern Utah. The trackway consists of prints of typical morphology, intermittent tail drags and, unusually, traces made by the animal resting on the substrate in a posture very similar to modern birds. The resting trace includes symmetrical pes impressions and well-defined impressions made by both hands, the tail, and the ischial callosity. The manus impressions corroborate that early theropods, like later birds, held their palms facing medially, in contrast to manus prints previously attributed to theropods that have forward-pointing digits. Both the symmetrical resting posture and the medially-facing palms therefore evolved by the Early Jurassic, much earlier in the theropod lineage than previously recognized, and may characterize all theropods.

  17. Concomitant fractional anisotropy and volumetric abnormalities in temporal lobe epilepsy: cross-sectional evidence for progressive neurologic injury.

    Directory of Open Access Journals (Sweden)

    Simon S Keller

    Full Text Available BACKGROUND: In patients with temporal lobe epilepsy and associated hippocampal sclerosis (TLEhs there are brain abnormalities extending beyond the presumed epileptogenic zone as revealed separately in conventional magnetic resonance imaging (MRI and MR diffusion tensor imaging (DTI studies. However, little is known about the relation between macroscopic atrophy (revealed by volumetric MRI and microstructural degeneration (inferred by DTI. METHODOLOGY/PRINCIPAL FINDINGS: For 62 patients with unilateral TLEhs and 68 healthy controls, we determined volumes and mean fractional anisotropy (FA of ipsilateral and contralateral brain structures from T1-weighted and DTI data, respectively. We report significant volume atrophy and FA alterations of temporal lobe, subcortical and callosal regions, which were more diffuse and bilateral in patients with left TLEhs relative to right TLEhs. We observed significant relationships between volume loss and mean FA, particularly of the thalamus and putamen bilaterally. When corrected for age, duration of epilepsy was significantly correlated with FA loss of an anatomically plausible route - including ipsilateral parahippocampal gyrus and temporal lobe white matter, the thalamus bilaterally, and posterior regions of the corpus callosum that contain temporal lobe fibres - that may be suggestive of progressive brain degeneration in response to recurrent seizures. CONCLUSIONS/SIGNIFICANCE: Chronic TLEhs is associated with interrelated DTI-derived and volume-derived brain degenerative abnormalities that are influenced by the duration of the disorder and the side of seizure onset. This work confirms previously contradictory findings by employing multi-modal imaging techniques in parallel in a large sample of patients.

  18. The transition from somatic to germline identity shows conserved and specialized features during angiosperm evolution.

    Science.gov (United States)

    Lora, Jorge; Herrero, María; Tucker, Matthew R; Hormaza, José I

    2017-10-01

    How and why specific plant cells adopt germline identity during ovule development has proved challenging to address, and the pathways that are active in the ovules of basal/early-divergent angiosperms possessing a multilayered nucellus are still unclear. Here, we compare megasporogenesis between two early-divergent angiosperms (Annona cherimola and Persea americana) and the evolutionarily derived Arabidopsis thaliana, studying the three-dimensional spatial position of the megaspore mother cell (MMC), the compositional details of the MMC wall and the location of PIN1 expression. Specific wall polymers distinguished the central position of the MMC and its meiotic products from surrounding tissues in early-divergent angiosperms, whereas, in A. thaliana, only callose (in mature MMCs) and arabinogalactan proteins (AGPs) (in megaspores) distinguished the germline. However, PIN1 expression, which regulates polar auxin transport, was observed around the MMC in the single-layer nucellus of A. thaliana and in the multilayered nucellus of A. cherimola, or close to the MMC in P. americana. The data reveal a similar microenvironment in relation to auxin during megasporogenesis in all three species. However, the different wall polymers that mark MMC fate in early-divergent angiosperms may reflect a specific response to mechanical stress during differentiation, or the specific recruitment of polymers to sustain MMC growth. © 2016 CSIC. New Phytologist © 2016 New Phytologist Trust.

  19. Secondary metabolites in plant innate immunity: conserved function of divergent chemicals.

    Science.gov (United States)

    Piasecka, Anna; Jedrzejczak-Rey, Nicolas; Bednarek, Paweł

    2015-05-01

    Plant secondary metabolites carry out numerous functions in interactions between plants and a broad range of other organisms. Experimental evidence strongly supports the indispensable contribution of many constitutive and pathogen-inducible phytochemicals to plant innate immunity. Extensive studies on model plant species, particularly Arabidopsis thaliana, have brought significant advances in our understanding of the molecular mechanisms underpinning pathogen-triggered biosynthesis and activation of defensive secondary metabolites. However, despite the proven significance of secondary metabolites in plant response to pathogenic microorganisms, little is known about the precise mechanisms underlying their contribution to plant immunity. This insufficiency concerns information on the dynamics of cellular and subcellular localization of defensive phytochemicals during the encounters with microbial pathogens and precise knowledge on their mode of action. As many secondary metabolites are characterized by their in vitro antimicrobial activity, these compounds were commonly considered to function in plant defense as in planta antibiotics. Strikingly, recent experimental evidence suggests that at least some of these compounds alternatively may be involved in controlling several immune responses that are evolutionarily conserved in the plant kingdom, including callose deposition and programmed cell death. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  20. Advances in induced resistance by natural compounds: towards new options for woody crop protection

    Directory of Open Access Journals (Sweden)

    Eugenio Llorens

    Full Text Available ABSTRACT: The activation of defensive responses of plants is a promising tool for controlling pests in conventional agriculture. Over the last few years, several compounds have been studied to protect crops from pests, without displaying direct toxicity for pathogenic organisms. These compounds have the ability to induce a priming state on the plants that results in resistance (or tolerance against subsequent infection by a pathogen. In terms of molecular response, induced plant defense involves a broad number of physical and biochemical changes such as callose deposition or phenolic compounds, activation of salicylic and/or jasmonic acid pathways or synthesis of defense-related enzymes. Despite the large number of studies performed to ascertain the physiological and biochemical basis of induced resistance, only a few resistance-activating compounds have been studied as a real alternative to classic means of control and the studies geared towards incorporating induced resistance into disease management programs are relatively rare. The incorporation of natural resistance inducer in pest management programs of woody crops, alone or in combination with classical methods, could be a reliable method for reducing the amount of chemical residues in the environment. In this review, we discuss the current knowledge of induced resistance in woody crops, focusing on the mode of action of compounds authorized for conventional agriculture. We conclude by discussing the environmental and economic advantages of applying resistance inducers to conventional agriculture with special emphasis on natural compounds.

  1. RUN1 and REN1 Pyramiding in Grapevine (Vitis vinifera cv. Crimson Seedless) Displays an Improved Defense Response Leading to Enhanced Resistance to Powdery Mildew (Erysiphe necator).

    Science.gov (United States)

    Agurto, Mario; Schlechter, Rudolf O; Armijo, Grace; Solano, Esteban; Serrano, Carolina; Contreras, Rodrigo A; Zúñiga, Gustavo E; Arce-Johnson, Patricio

    2017-01-01

    Fungal pathogens are the cause of the most common diseases in grapevine and among them powdery mildew represents a major focus for disease management. Different strategies for introgression of resistance in grapevine are currently undertaken in breeding programs. For example, introgression of several resistance genes (R) from different sources for making it more durable and also strengthening the plant defense response. Taking this into account, we cross-pollinated P09-105/34, a grapevine plant carrying both RUN1 and REN1 pyramided loci of resistance to Erysiphe necator inherited from a pseudo-backcrossing scheme with Muscadinia rotundifolia and Vitis vinifera 'Dzhandzhal Kara,' respectively, with the susceptible commercial table grape cv. 'Crimson Seedless.' We developed RUN1REN1 resistant genotypes through conventional breeding and identified them by marker assisted selection. The characterization of defense response showed a highly effective defense mechanism against powdery mildew in these plants. Our results reveal that RUN1REN1 grapevine plants display a robust defense response against E. necator, leading to unsuccessful fungal establishment with low penetration rate and poor hypha development. This resistance mechanism includes reactive oxygen species production, callose accumulation, programmed cell death induction and mainly VvSTS36 and VvPEN1 gene activation. RUN1REN1 plants have a great potential as new table grape cultivars with durable complete resistance to E. necator, and are valuable germplasm to be included in grape breeding programs to continue pyramiding with other sources of resistance to grapevine diseases.

  2. MRI of pineal region tumours: relationship between tumours and adjacent structures

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, H. [Hiroshima University, School of Medicine (Japan). Dept. of Neurosurgery; Uozumi, T. [Hiroshima University, School of Medicine (Japan). Dept. of Neurosurgery; Kiya, K. [Dept. of Neurosurgery, Hiroshima Prefectural Hospital, Hiroshima (Japan); Kurisu, K. [Hiroshima University, School of Medicine (Japan). Dept. of Neurosurgery; Arita, K. [Hiroshima University, School of Medicine (Japan). Dept. of Neurosurgery; Sumida, M. [Hiroshima University, School of Medicine (Japan). Dept. of Neurosurgery; Ikawa, F. [Dept. of Neurosurgery, Hiroshima Prefectural Hospital, Hiroshima (Japan)

    1995-11-01

    A variety of tumours may arise in the pineal region; accurate diagnosis is important in the selection of treatment and prognosis. A retrospective analysis of the MRI studies of 25 patients with pathologically proven pineal region tumours was performed, focused on the relationship between the tumour and neighbouring structures. Compression of the tectal plate was classified as expansive or invasive, and compression of the corpus callosum as inferior, anterior or posterior. In 10 of the 14 patients (71 %) with germ cell tumours tectal compression was of the invasive type; 8 patients (57 %) had multiple tumours and in 13 (93 %) the tumour margins were irregular. Teratomas were readily diagnosed because of characteristic heterogeneous signal intensity. Pineal cell tumours were differentiated from germ cell tumours by their rounded shape, solid nature, sharp margins, and expansive type of tectal compression. Meningiomas were characterised by their falcotentorial attachments, posterior callosal compression, and a low-intensity rim on T2-weighted images. Gd-DTPA injection enabled clear demonstration of the site and extent of tumour spread and was useful in differentiating cystic and solid components. The appearances described, while not pathognomonic, are helpful in the differential diagnosis of pineal region tumours, and valuable in planning appropriate treatment. (orig.). With 4 figs., 6 tabs.

  3. Arabidopsis EF-Tu receptor enhances bacterial disease resistance in transgenic wheat.

    Science.gov (United States)

    Schoonbeek, Henk-Jan; Wang, Hsi-Hua; Stefanato, Francesca L; Craze, Melanie; Bowden, Sarah; Wallington, Emma; Zipfel, Cyril; Ridout, Christopher J

    2015-04-01

    Perception of pathogen (or microbe)-associated molecular patterns (PAMPs/MAMPs) by pattern recognition receptors (PRRs) is a key component of plant innate immunity. The Arabidopsis PRR EF-Tu receptor (EFR) recognizes the bacterial PAMP elongation factor Tu (EF-Tu) and its derived peptide elf18. Previous work revealed that transgenic expression of AtEFR in Solanaceae confers elf18 responsiveness and broad-spectrum bacterial disease resistance. In this study, we developed a set of bioassays to study the activation of PAMP-triggered immunity (PTI) in wheat. We generated transgenic wheat (Triticum aestivum) plants expressing AtEFR driven by the constitutive rice actin promoter and tested their response to elf18. We show that transgenic expression of AtEFR in wheat confers recognition of elf18, as measured by the induction of immune marker genes and callose deposition. When challenged with the cereal bacterial pathogen Pseudomonas syringae pv. oryzae, transgenic EFR wheat lines had reduced lesion size and bacterial multiplication. These results demonstrate that AtEFR can be transferred successfully from dicot to monocot species, further revealing that immune signalling pathways are conserved across these distant phyla. As novel PRRs are identified, their transfer between plant families represents a useful strategy for enhancing resistance to pathogens in crops. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  4. Developmental study of dendritic bundles in layer 1 of the rat granular retrosplenial cortex with special reference to a cell adhesion molecule, OCAM.

    Science.gov (United States)

    Ichinohe, Noritaka; Yoshihara, Yoshihiro; Hashikawa, Tsutomu; Rockland, Kathleen S

    2003-10-01

    In the granular retrosplenial cortex (GRS) of adult rats, callosally projecting pyramidal neurons in layer 2 form dendritic bundles, 30-100 micro m wide, in layer 1. The distinctness of these bundles makes the GRS an attractive model system for investigating the developmental, microcircuitry, and basic organizational features related to dendritic modularity. In this report, we investigate the developmental time course of the dendritic bundles, visualized by immunohistochemistry for microtubule-associated protein 2 (MAP2) and glutamate receptor subunits 2/3 (GluR2/3). Bundles in layer 1 are apparent as early as postnatal day 5, first with GluR2/3 and then, from postnatal day 14, with MAP2. As a step toward understanding the mechanisms of dendritic aggregation, we further investigated the ontogeny of expression of the cell adhesion molecule OCAM. OCAM exhibits a patchy distribution in layer 1 from postnatal day 3 to adult, and the regions of weak OCAM immunoreactivity selectively correspond to the dendritic bundles (in both GluR2/3 and MAP2). The periodic geometry of OCAM-immunoreactive regions, the time course of their appearance and the distinct localization complementary to the bundles support the possibility that this molecule is one contributor to the establishment and maintenance of dendritic modules. The interdigitating relationship between regions of high OCAM immunoreactivity and the dendritic bundles in layer 1 suggests that OCAM may have a repellent influence on the formation of these bundles.

  5. Pediatric Balint’s Syndrome Variant: A Possible Diagnosis in Children

    Directory of Open Access Journals (Sweden)

    Swetha Sara Philip

    2016-01-01

    Full Text Available Balint’s syndrome is well described in adults, but not in children. It is caused by bilateral posterior parietal lobe damage and comprises a triad of simultanagnosia (inability to simultaneously see more than a small number of items, optic ataxia (impaired visual guidance of movement of the limbs and body, and apraxia of gaze (inability to volitionally direct gaze despite the requisite motor substrate often associated with homonymous lower visual field loss. We, here, describe five children (four males, one female; mean age 7.4 years, [range 4−11 years]; birth weight ≤ 2.5 kg; four were born ≤ 36 weeks of gestational age and one at 40 weeks who presented to the Cerebral Visual Impairment Clinic at a tertiary care center in South India with clinical features remarkably consistent with the above description. In all children neuroimaging showed bilateral parietooccipital gliosis with regional white matter volume loss and focal callosal thinning, consistent with perinatal hypoxic ischemic encephalopathy and possible neonatal hypoglycemia.

  6. Pediatric Balint's Syndrome Variant: A Possible Diagnosis in Children.

    Science.gov (United States)

    Philip, Swetha Sara; Mani, Sunithi Elizabeth; Dutton, Gordon N

    2016-01-01

    Balint's syndrome is well described in adults, but not in children. It is caused by bilateral posterior parietal lobe damage and comprises a triad of simultanagnosia (inability to simultaneously see more than a small number of items), optic ataxia (impaired visual guidance of movement of the limbs and body), and apraxia of gaze (inability to volitionally direct gaze despite the requisite motor substrate) often associated with homonymous lower visual field loss. We, here, describe five children (four males, one female; mean age 7.4 years, [range 4-11 years]; birth weight ≤ 2.5 kg; four were born ≤ 36 weeks of gestational age and one at 40 weeks) who presented to the Cerebral Visual Impairment Clinic at a tertiary care center in South India with clinical features remarkably consistent with the above description. In all children neuroimaging showed bilateral parietooccipital gliosis with regional white matter volume loss and focal callosal thinning, consistent with perinatal hypoxic ischemic encephalopathy and possible neonatal hypoglycemia.

  7. Extensive intracranial calcification of pseudo-TORCH syndrome with features of Dandy–Walker malformation

    Science.gov (United States)

    Patnaik, Ashis; Mishra, Sudhansu Sekhar; Das, Srikanta

    2017-01-01

    Pseudo-TORCH syndrome or congenital infection-like syndrome is a group of conditions which resemble congenital infections such as those caused by toxoplasmosis, rubella, cytomegalovirus (CMV), herpes (TORCH) group of organisms, clinico-radiologically, but serological tests are negative for the organisms. One of the variety shows features such as microcephaly, extensive intracranial calcification showing gross resemblance to congenital CMV infection, making its other name as microcephaly intracranial calcification syndrome (MICS). Dandy–Walker malformation (DWM), in addition to posterior fossa large cyst, cerebellar vermis hypoplasia, and hydrocephalus is often associated with agenesis of the corpus callosum and callosal lipomas, dysplasia of the brainstem, and cerebellar hypoplasia or dysgenesis. But radiological features of DWM with microcephaly and intracranial calcification are very unusual and have been rarely reported in the literature.[1] We report a case of infant showing clinical features suggestive of congenital CMV infection with negative serology and radiological imaging suggestive of DWM with extensive intracranial calcification. Pseudo-TORCH syndrome with radiological features of DWM is a congenital developmental abnormality. Inspite of hydrocephalus, it does not require cerebrospinal fluid (CSF) diversionary procedure due to lack of increased intracranial pressure. Conservative management for seizure disorder is the optimal therapy. PMID:28761539

  8. Extensive intracranial calcification of pseudo-TORCH syndrome with features of Dandy-Walker malformation.

    Science.gov (United States)

    Patnaik, Ashis; Mishra, Sudhansu Sekhar; Das, Srikanta

    2017-01-01

    Pseudo-TORCH syndrome or congenital infection-like syndrome is a group of conditions which resemble congenital infections such as those caused by toxoplasmosis, rubella, cytomegalovirus (CMV), herpes (TORCH) group of organisms, clinico-radiologically, but serological tests are negative for the organisms. One of the variety shows features such as microcephaly, extensive intracranial calcification showing gross resemblance to congenital CMV infection, making its other name as microcephaly intracranial calcification syndrome (MICS). Dandy-Walker malformation (DWM), in addition to posterior fossa large cyst, cerebellar vermis hypoplasia, and hydrocephalus is often associated with agenesis of the corpus callosum and callosal lipomas, dysplasia of the brainstem, and cerebellar hypoplasia or dysgenesis. But radiological features of DWM with microcephaly and intracranial calcification are very unusual and have been rarely reported in the literature.[1] We report a case of infant showing clinical features suggestive of congenital CMV infection with negative serology and radiological imaging suggestive of DWM with extensive intracranial calcification. Pseudo-TORCH syndrome with radiological features of DWM is a congenital developmental abnormality. Inspite of hydrocephalus, it does not require cerebrospinal fluid (CSF) diversionary procedure due to lack of increased intracranial pressure. Conservative management for seizure disorder is the optimal therapy.

  9. Cortical brain connectivity evaluated by graph theory in dementia: a correlation study between functional and structural data.

    Science.gov (United States)

    Vecchio, Fabrizio; Miraglia, Francesca; Curcio, Giuseppe; Altavilla, Riccardo; Scrascia, Federica; Giambattistelli, Federica; Quattrocchi, Carlo Cosimo; Bramanti, Placido; Vernieri, Fabrizio; Rossini, Paolo Maria

    2015-01-01

    A relatively new approach to brain function in neuroscience is the "functional connectivity", namely the synchrony in time of activity in anatomically-distinct but functionally-collaborating brain regions. On the other hand, diffusion tensor imaging (DTI) is a recently developed magnetic resonance imaging (MRI)-based technique with the capability to detect brain structural connection with fractional anisotropy (FA) identification. FA decrease has been observed in the corpus callosum of subjects with Alzheimer's disease (AD) and mild cognitive impairment (MCI, an AD prodromal stage). Corpus callosum splenium DTI abnormalities are thought to be associated with functional disconnections among cortical areas. This study aimed to investigate possible correlations between structural damage, measured by MRI-DTI, and functional abnormalities of brain integration, measured by characteristic path length detected in resting state EEG source activity (40 participants: 9 healthy controls, 10 MCI, 10 mild AD, 11 moderate AD). For each subject, undirected and weighted brain network was built to evaluate graph core measures. eLORETA lagged linear connectivity values were used as weight of the edges of the network. Results showed that callosal FA reduction is associated to a loss of brain interhemispheric functional connectivity characterized by increased delta and decreased alpha path length. These findings suggest that "global" (average network shortest path length representing an index of how efficient is the information transfer between two parts of the network) functional measure can reflect the reduction of fiber connecting the two hemispheres as revealed by DTI analysis and also anticipate in time this structural loss.

  10. Spermine Regulates Pollen Tube Growth by Modulating Ca2+-Dependent Actin Organization and Cell Wall Structure

    Science.gov (United States)

    Aloisi, Iris; Cai, Giampiero; Faleri, Claudia; Navazio, Lorella; Serafini-Fracassini, Donatella; Del Duca, Stefano

    2017-01-01

    Proper growth of the pollen tube depends on an elaborate mechanism that integrates several molecular and cytological sub-processes and ensures a cell shape adapted to the transport of gametes. This growth mechanism is controlled by several molecules among which cytoplasmic and apoplastic polyamines. Spermine (Spm) has been correlated with various physiological processes in pollen, including structuring of the cell wall and modulation of protein (mainly cytoskeletal) assembly. In this work, the effects of Spm on the growth of pear pollen tubes were analyzed. When exogenous Spm (100 μM) was supplied to germinating pollen, it temporarily blocked tube growth, followed by the induction of apical swelling. This reshaping of the pollen tube was maintained also after growth recovery, leading to a 30–40% increase of tube diameter. Apical swelling was also accompanied by a transient increase in cytosolic calcium concentration and alteration of pH values, which were the likely cause for major reorganization of actin filaments and cytoplasmic organelle movement. Morphological alterations of the apical and subapical region also involved changes in the deposition of pectin, cellulose, and callose in the cell wall. Thus, results point to the involvement of Spm in cell wall construction as well as cytoskeleton organization during pear pollen tube growth. PMID:29033970

  11. Two thiadiazole compounds promote rice defence against Xanthomonas oryzae pv. oryzae by suppressing the bacterium's production of extracellular polysaccharides.

    Science.gov (United States)

    Liang, Xiaoyu; Yu, Xiaoyue; Dong, Wenxia; Guo, Shijian; Xu, Shu; Wang, Jianxin; Zhou, Mingguo

    2015-10-01

    Thiazole, isothiazole, thiadiazole, and their derivatives are used to control various human, animal and plant diseases. In addition to having direct anti-microbial and anti-fungal properties, these compounds are thought to induce host defences, but the mechanism of defence induction remains poorly understood. This article reports that the thiadiazoles of zinc thiazole and bismerthiazol induce H2 O2 accumulation, up-regulation of defence-related genes, callose deposition and hypersensitive response-like cell death in rice leaves infected with Xanthomonas oryaze pv. oryzae (Xoo) strain ZJ173, but not in non-infected leaves. These defence responses in Xoo-infected leaves were suppressed by the exogenous application of catalase, which reduces H2 O2 accumulation. The application of extracellular polysaccharides (EPSs) extracted from strain ZJ173 significantly compromised rice defence against ZJ173 with or without thiadiazole treatment. The EPS-deficient Xoo mutant ∆gumH triggered a stronger defence than its parent strain ZJ173. The thiadiazole treatments reduced EPS production by strain ZJ173, but not by the thiadiazole-resistant strain 2-1-1, which is thiadiazole resistant in vivo, but not in vitro; moreover, enhanced defence was not detected in thiadiazole-treated rice inoculated with 2-1-1. Based on these data, we infer that zinc thiazole and bismerthiazol promote rice defence against Xoo by inhibiting the production of bacterial EPS. © 2015 BSPP AND JOHN WILEY & SONS LTD.

  12. Foot Injuries Among Hajj Pilgrims with and Without Diabetes Mellitus: Implications for Infection Management.

    Science.gov (United States)

    Alfelali, Mohammad; Barasheed, Osamah; Alshehri, Jassir; Bokhary, Hamid; Alsaedi, Sami; Alhamzi, Abdulrahman; Aljohani, Naji; Driscoll, Tim; Rashid, Harunor

    2014-01-01

    Pilgrims attending Hajj in Makkah are at high risk of suffering from trauma and foot injury as they are required to make circuits barefooted on scorching marbles around the Holy Mosque, and march between two hillocks for hours. No study has systematically described the pattern of foot wounds among them. This observational study aimed to determine the spectrum of foot injuries among diabetic and non-diabetic Hajj pilgrims and the preventive measures adopted by them. Pilgrims who attended the Hajj 2013 and sought medical care for foot wounds at mobile podiatric clinics in Mina during the peak days of Hajj were invited to participate in the study and fill out a questionnaire while they were serviced. Podiatric carers noted down the significant signs of foot injuries. Out of 197 pilgrims from 21 different countries who participated in this study, 60 (31%) were diabetic. The two most common injuries observed were blisters (34%) and erythema (25%). Both diabetic and non-diabetic Hajj pilgrims were at high risk of developing infectious wounds, however a significantly higher proportion of diabetic pilgrims had callosities. Use of appropriately fitting protective footwear, and regularity in diets and drugs are highly recommended for pilgrims' optimum foot care. Tailored educational advice on foot hygiene before and during travel could be beneficial for Hajj pilgrims.

  13. Glucanocellulosic ethanol: the undiscovered biofuel potential in energy crops and marine biomass.

    Science.gov (United States)

    Falter, Christian; Zwikowics, Claudia; Eggert, Dennis; Blümke, Antje; Naumann, Marcel; Wolff, Kerstin; Ellinger, Dorothea; Reimer, Rudolph; Voigt, Christian A

    2015-09-01

    Converting biomass to biofuels is a key strategy in substituting fossil fuels to mitigate climate change. Conventional strategies to convert lignocellulosic biomass to ethanol address the fermentation of cellulose-derived glucose. Here we used super-resolution fluorescence microscopy to uncover the nanoscale structure of cell walls in the energy crops maize and Miscanthus where the typical polymer cellulose forms an unconventional layered architecture with the atypical (1, 3)-β-glucan polymer callose. This raised the question about an unused potential of (1, 3)-β-glucan in the fermentation of lignocellulosic biomass. Engineering biomass conversion for optimized (1, 3)-β-glucan utilization, we increased the ethanol yield from both energy crops. The generation of transgenic Miscanthus lines with an elevated (1, 3)-β-glucan content further increased ethanol yield providing a new strategy in energy crop breeding. Applying the (1, 3)-β-glucan-optimized conversion method on marine biomass from brown macroalgae with a naturally high (1, 3)-β-glucan content, we not only substantially increased ethanol yield but also demonstrated an effective co-fermentation of plant and marine biomass. This opens new perspectives in combining different kinds of feedstock for sustainable and efficient biofuel production, especially in coastal regions.

  14. Benzothiadiazole-Mediated Induced Resistance to Fusarium oxysporum f. sp. radicis-lycopersici in Tomato1

    Science.gov (United States)

    Benhamou, Nicole; Bélanger, Richard R.

    1998-01-01

    Benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH), a synthetic chemical, was applied as a foliar spray to tomato (Lycopersicon esculentum) plants and evaluated for its potential to confer increased resistance against the soil-borne pathogen Fusarium oxysporum f. sp. radicis-lycopersici (FORL). In nontreated tomato plants all root tissues were massively colonized by FORL hyphae. Pathogen ingress toward the vascular stele was accompanied by severe host cell alterations, including cell wall breakdown. In BTH-treated plants striking differences in the rate and extent of fungal colonization were observed. Pathogen growth was restricted to the epidermis and the outer cortex, and fungal ingress was apparently halted by the formation of callose-enriched wall appositions at sites of fungal penetration. In addition, aggregated deposits, which frequently established close contact with the invading hyphae, accumulated in densely colonized epidermal cells and filled most intercellular spaces. Upon incubation of sections with gold-complexed laccase for localization of phenolic-like compounds, a slight deposition of gold particles was observed over both the host cell walls and the wall appositions. Labeling was also detected over the walls of fungal cells showing signs of obvious alteration ranging from cytoplasm disorganization to protoplasm retraction. We provide evidence that foliar applications of BTH sensitize susceptible tomato plants to react more rapidly and more efficiently to FORL attack through the formation of protective layers at sites of potential fungal entry. PMID:9847094

  15. Comparison of Postoperative Height Changes of the Second Metatarsal Among 3 Osteotomy Methods for Hallux Valgus Deformity Correction.

    Science.gov (United States)

    Choi, Jun Young; Suh, Yu Min; Yeom, Ji Woong; Suh, Jin Soo

    2017-01-01

    We aimed to compare the postoperative height of the second metatarsal head relative to the first metatarsal head using axial radiographs among 3 different commonly used osteotomy techniques: proximal chevron metatarsal osteotomy (PCMO), scarf osteotomy, and distal chevron metatarsal osteotomy (DCMO). We retrospectively reviewed the radiographs and clinical findings of the patients with painful callosities under the second metatarsal head, complicated by hallux valgus, who underwent isolated PCMO, scarf osteotomy, or DCMO from February 2005 to January 2015. Each osteotomy was performed with 20 degrees of plantar ward obliquity. Along with lateral translation and rotation of the distal fragment to correct the deformity, lowering of the first metatarsal head was made by virtue of the oblique metatarsal osteotomy. Significant postoperative change in the second metatarsal height was observed on axial radiographs in all groups; this value was greatest in the PCMO group (vs scarf: P = .013; vs DCMO: P = .008) but did not significantly differ between the scarf and DCMO groups ( P = .785). The power for second metatarsal height correction was significantly greater in the PCMO group (vs scarf: P = .0005; vs DCMO: P = .0005) but did not significantly differ between the scarf and DCMO groups ( P = .832). Among the 3 osteotomy techniques commonly used to correct hallux valgus deformity, we observed that PCMO yielded the most effective height change of the second metatarsal head. Level III, retrospective comparative series.

  16. Comparative transcriptional and anatomical analyses of tolerant rough lemon and susceptible sweet orange in response to 'Candidatus Liberibacter asiaticus' infection.

    Science.gov (United States)

    Fan, Jing; Chen, Chunxian; Yu, Qibin; Khalaf, Abeer; Achor, Diann S; Brlansky, Ron H; Moore, Gloria A; Li, Zheng-Guo; Gmitter, Frederick G

    2012-11-01

    Although there are no known sources of genetic resistance, some Citrus spp. are reportedly tolerant to huanglongbing (HLB), presumably caused by 'Candidatus Liberibacter asiaticus'. Time-course transcriptional analysis of tolerant rough lemon (Citrus jambhiri) and susceptible sweet orange (C. sinensis) in response to 'Ca. L. asiaticus' infection showed more genes differentially expressed in HLB-affected rough lemon than sweet orange at early stages but substantially fewer at late time points, possibly a critical factor underlying differences in sensitivity to 'Ca. L. asiaticus'. Pathway analysis revealed that stress responses were distinctively modulated in rough lemon and sweet orange. Although microscopic changes (e.g., callose deposition in sieve elements and phloem cell collapse) were found in both infected species, remarkably, phloem transport activity in midribs of source leaves in rough lemon was much less affected by HLB than in sweet orange. The difference in phloem cell transport activities is also implicated in the differential sensitivity to HLB between the two species. The results potentially lead to identification of key genes and the genetic mechanism in rough lemon to restrain disease development and maintain (or recover) phloem transport activity. These potential candidate genes may be used for improving citrus tolerance (or even resistance) to HLB by genetic engineering.

  17. Microspore development in Annona (Annonaceae): differences between monad and tetrad pollen.

    Science.gov (United States)

    Lora, Jorge; Herrero, Maria; Hormaza, Jose I

    2014-09-01

    • Permanent tetrads are the most common form of pollen aggregation in flowering plants. The production of pollen in monads is plesiomorphic in angiosperms, but the aggregation into tetrads has arisen independently different times during the evolution of flowering plants. The causes behind the recurrent evolution of pollen aggregation from monads remain elusive. Permanent tetrad pollen is quite common in the Annonaceae, the largest family in the early-divergent order Magnoliales. In some genera, such as Annona, both tetrad- and monad-producing species can be found.• In this comparative study of pollen development, we use immunolocalization, cytological characterization, and enzymatic assays of four species in the genus Annona and one species in its closely related genus Asimina that release pollen in tetrads and two species in the genus Annona that release pollen in monads.• The main difference between species with tetrad and monad pollen is a delayed digestion of callose and cellulose at the pollen aperture sites that resulted in nonlayering of the exine in these areas, followed by a rotation and binding of the young microspores at the aperture sites.• Small changes in development resulted in clear morphological changes on pollen dispersal time and open a window on the possible selective advantage of the production of aggregated pollen. © 2014 Botanical Society of America, Inc.

  18. The benefit of image guidance for the contralateral interhemispheric approach to the lateral ventricle.

    Science.gov (United States)

    Fronda, Chiara; Miller, Dorothea; Kappus, Christoph; Bertalanffy, Helmut; Sure, Ulrich

    2008-06-01

    Recently, neurosurgeons have increasingly faced small intracerebral lesions in asymptomatic or minimally symptomatic patients. Here, we evaluated a series of four patients with nearly asymptomatic intraventricular tumors close to the corpus callosum that had been treated with the aid of an image-guided transcallosal approach. Four consecutive patients suffering from left intra- and paraventricular tumors were operated on via a contralateral interhemispheric transcallosal approach with the aid of neuronavigation. Our image-guided system directed: (1) the skin incision, (2) the interhemispheric dissection, and (3) the incision of the corpus callosum. Using the image-guided contralateral interhemispheric transcallosal approach to the left ventricle all lesions have been completely resected without the risk of damage to the dominant hemisphere. The callosal incision was kept as limited as possible (1.2-2.1cm) depending on the size of the tumor. No postoperative neurological or neuropsychological deficit was observed in our series. Neuronavigation facilitates a safe and targeted contralateral interhemispheric transcallosal approach to the dominant hemisphere's lateral ventricle. Our technique minimizes the risk of damage to the dominant hemisphere and requires only a limited opening of the corpus callosum, which might decrease the risk of neuropsychological morbidity.

  19. Insights into thermoregulation: A clinico-radiological description of Shapiro syndrome.

    LENUS (Irish Health Repository)

    Pazderska, Agnieszka

    2013-06-15

    Shapiro syndrome is a rare entity, comprising a triad of recurrent hypothermia, hyperhidrosis and congenital agenesis of the corpus callosum. Fewer than 50 cases have been described, almost invariably in patients presenting in childhood or early adulthood. We present a case of an 80year old woman presenting with recurrent bouts of shivering, sweating and profound malaise, who sought medical attention because the frequency and severity of attacks worsened in her later years. MRI Brain demonstrated agenesis of the corpus callosum; a rigorous work-up excluded other causes for her symptomatology. The intricate interplay of neuronal networks involved in thermoregulation remains to be fully elucidated and as such, little is known about the pathophysiological mechanisms underlying the clinical manifestations of Shapiro syndrome. We present novel data from FDG-PET imaging of our patient, demonstrating hypermetabolism in a number of brainstem and cerebellar regions during the symptomatic phase. These findings imply that aberrant thermoregulation in Shapiro syndrome involves a number of structures remote from the callosal region. We also present neuropsychometric findings in our patient, of which there have been no reports to date. We postulate that the ageing brain may be more susceptible to the paroxysmal neurochemical fluxes implicated in the syndrome.

  20. Risk of multiple sclerosis after a first demyelinating syndrome in an Australian Paediatric cohort: clinical, radiological features and application of the McDonald 2010 MRI criteria.

    Science.gov (United States)

    Tantsis, Esther M; Prelog, Kristina; Brilot, Fabienne; Dale, Russell C

    2013-11-01

    The risk of multiple sclerosis (MS) is dependent on multiple variables, including geographical location. There is increasing interest in the early recognition and treatment of MS in children. Using univariate and multivariate analysis, we determined the clinical and radiological features that were predictive of MS in 88 children from New South Wales, Australia, with a first acute demyelinating syndrome (ADS) who were followed for a minimum of one year. We tested the McDonald, KIDMUS, Callen and Verhey MRI criteria for paediatric MS. After a mean follow-up of 5.2 years, 13/88 (15%) of children had MS. Using multivariate analysis, preceding infection was protective of MS, and corpus callosal lesions, the combined presence of both well and poorly demarcated lesions, and contrast-enhancing lesions on MRI were predictive of MS. The sensitivity and specificity of the respective radiological criteria were McDonald 2005 (69%, 68%), McDonald 2010 (58%, 95%), KIDMUS (8%, 100%), Callen (69%, 85%) and Verhey (62%, 84%). When McDonald 2010 criteria were applied to baseline and serial scans, the sensitivity and specificity was 91% and 93%. Despite the long follow-up, the risk of MS appears lower in New South Wales children compared to previously reported cohorts. Radiological features are more predictive than clinical features in predicting MS. The McDonald 2010 criteria performed well although the dissemination in time criteria on baseline scans is difficult to apply to children with encephalopathy.

  1. The effect of injury timing on white matter changes in the corpus callosum following unilateral brain injury☆

    Science.gov (United States)

    Hawe, Rachel L.; Sukal-Moulton, Theresa; Dewald, Julius P.A.

    2013-01-01

    Motor impairments following unilateral brain injuries may be related to changes in the corpus callosum. The purpose of this study was to determine if the corpus callosum is impacted differently in pediatric versus adult hemiplegia. Diffusion tensor imaging was completed on 41 participants (11 pediatric hemiplegia, 10 adult hemiplegia, 10 pediatric control and 10 adult control). Fractional anisotropy values and cross-sectional areas for five regions of the corpus callosum were compared between subject groups. Additionally, the amount of involuntary activity in the paretic elbow was quantified during non-paretic elbow flexion tasks for a subset of pediatric hemiplegia participants. Fractional anisotropy values were reduced in pediatric hemiplegia compared to pediatric control subjects in callosal regions corresponding to premotor and supplementary motor areas, primary sensory cortex, and parietal, temporal, and occipital cortices. Differences in fractional anisotropy between adult stroke and adult controls were only found in the region corresponding to parietal, temporal, and occipital cortices. Cross-sectional area was affected in all regions of the corpus callosum in pediatric hemiplegia, but only in the primary sensory region in adult hemiplegia. Additionally, changes in the cross-sectional areas were correlated with involuntary mirror movements in the pediatric hemiplegia group. In conclusion, the corpus callosum is affected to a greater extent in pediatric compared to adult hemiplegia, which may explain why unsuppressed mirror movements and difficulty with bimanual coordination are greater problems in this population. PMID:24179855

  2. Hemispheric connectivity and the visual-spatial divergent-thinking component of creativity.

    Science.gov (United States)

    Moore, Dana W; Bhadelia, Rafeeque A; Billings, Rebecca L; Fulwiler, Carl; Heilman, Kenneth M; Rood, Kenneth M J; Gansler, David A

    2009-08-01

    Divergent thinking is an important measurable component of creativity. This study tested the postulate that divergent thinking depends on large distributed inter- and intra-hemispheric networks. Although preliminary evidence supports increased brain connectivity during divergent thinking, the neural correlates of this characteristic have not been entirely specified. It was predicted that visuospatial divergent thinking would correlate with right hemisphere white matter volume (WMV) and with the size of the corpus callosum (CC). Volumetric magnetic resonance imaging (MRI) analyses and the Torrance Tests of Creative Thinking (TTCT) were completed among 21 normal right-handed adult males. TTCT scores correlated negatively with the size of the CC and were not correlated with right or, incidentally, left WMV. Although these results were not predicted, perhaps, as suggested by Bogen and Bogen (1988), decreased callosal connectivity enhances hemispheric specialization, which benefits the incubation of ideas that are critical for the divergent-thinking component of creativity, and it is the momentary inhibition of this hemispheric independence that accounts for the illumination that is part of the innovative stage of creativity. Alternatively, decreased CC size may reflect more selective developmental pruning, thereby facilitating efficient functional connectivity.

  3. Alterações anatômicas em algodoeiro infectado pelo vírus da doença azul Anatomical alterations in blue disease infected cotton plant

    Directory of Open Access Journals (Sweden)

    Juliana K. Takimoto

    2009-01-01

    Luteoviridae family. Aiming to understand virus-host pathogenesis as well as to contribute with diagnostic and breeding aspects of cotton blue disease, in the present work, structural studies were performed via anatomical comparative analysis of health and infected plant tissues. For the anatomical studies, leaves from infected cotton plants were chosen when showing typical symptoms, such as: stunting, reduced leaf area with chlorotic vein and edges curled downward; clustered leaves, flowers and fruits due to reduced stem internodes. The results revealed that infected tissues present an increase in callose accumulation and calcium oxalate crystals; integrity of chloroplasts, which were distributed on the peripheral mesophyll cells, revealed a chemical alteration in the interior of palisade parenchyma cells. Inclusions in phloem and occasionally also xylem vessels were observed. The callose accumulation and the presence of inclusions in the phloem vessels are indications of a preferential relationship of the virus to these tissues.

  4. EPG5-related Vici syndrome: a paradigm of neurodevelopmental disorders with defective autophagy.

    Science.gov (United States)

    Byrne, Susan; Jansen, Lara; U-King-Im, Jean-Marie; Siddiqui, Ata; Lidov, Hart G W; Bodi, Istvan; Smith, Luke; Mein, Rachael; Cullup, Thomas; Dionisi-Vici, Carlo; Al-Gazali, Lihadh; Al-Owain, Mohammed; Bruwer, Zandre; Al Thihli, Khalid; El-Garhy, Rana; Flanigan, Kevin M; Manickam, Kandamurugu; Zmuda, Erik; Banks, Wesley; Gershoni-Baruch, Ruth; Mandel, Hanna; Dagan, Efrat; Raas-Rothschild, Annick; Barash, Hila; Filloux, Francis; Creel, Donnell; Harris, Michael; Hamosh, Ada; Kölker, Stefan; Ebrahimi-Fakhari, Darius; Hoffmann, Georg F; Manchester, David; Boyer, Philip J; Manzur, Adnan Y; Lourenco, Charles Marques; Pilz, Daniela T; Kamath, Arveen; Prabhakar, Prab; Rao, Vamshi K; Rogers, R Curtis; Ryan, Monique M; Brown, Natasha J; McLean, Catriona A; Said, Edith; Schara, Ulrike; Stein, Anja; Sewry, Caroline; Travan, Laura; Wijburg, Frits A; Zenker, Martin; Mohammed, Shehla; Fanto, Manolis; Gautel, Mathias; Jungbluth, Heinz

    2016-03-01

    Vici syndrome is a progressive neurodevelopmental multisystem disorder due to recessive mutations in the key autophagy gene EPG5. We report genetic, clinical, neuroradiological, and neuropathological features of 50 children from 30 families, as well as the neuronal phenotype of EPG5 knock-down in Drosophila melanogaster. We identified 39 different EPG5 mutations, most of them truncating and predicted to result in reduced EPG5 protein. Most mutations were private, but three recurrent mutations (p.Met2242Cysfs*5, p.Arg417*, and p.Gln336Arg) indicated possible founder effects. Presentation was mainly neonatal, with marked hypotonia and feeding difficulties. In addition to the five principal features (callosal agenesis, cataracts, hypopigmentation, cardiomyopathy, and immune dysfunction), we identified three equally consistent features (profound developmental delay, progressive microcephaly, and failure to thrive). The manifestation of all eight of these features has a specificity of 97%, and a sensitivity of 89% for the presence of an EPG5 mutation and will allow informed decisions about genetic testing. Clinical progression was relentless and many children died in infancy. Survival analysis demonstrated a median survival time of 24 months (95% confidence interval 0-49 months), with only a 10th of patients surviving to 5 years of age. Survival outcomes were significantly better in patients with compound heterozygous mutations (P = 0.046), as well as in patients with the recurrent p.Gln336Arg mutation. Acquired microcephaly and regression of skills in long-term survivors suggests a neurodegenerative component superimposed on the principal neurodevelopmental defect. Two-thirds of patients had a severe seizure disorder, placing EPG5 within the rapidly expanding group of genes associated with early-onset epileptic encephalopathies. Consistent neuroradiological features comprised structural abnormalities, in particular callosal agenesis and pontine hypoplasia, delayed

  5. Aluminium reduces sugar uptake in tobacco cell cultures: a potential cause of inhibited elongation but not of toxicity

    Science.gov (United States)

    Abdel-Basset, Refat; Ozuka, Shotaro; Demiral, Tijen; Furuichi, Takuya; Sawatani, Ikuo; Baskin, Tobias I.; Matsumoto, Hideaki; Yamamoto, Yoko

    2010-01-01

    Aluminium is well known to inhibit plant elongation, but the role in this inhibition played by water relations remains unclear. To investigate this, tobacco (Nicotiana tabacum L.) suspension-cultured cells (line SL) was used, treating them with aluminium (50 μM) in a medium containing calcium, sucrose, and MES (pH 5.0). Over an 18 h treatment period, aluminium inhibited the increase in fresh weight almost completely and decreased cellular osmolality and internal soluble sugar content substantially; however, aluminium did not affect the concentrations of major inorganic ions. In aluminium-treated cultures, fresh weight, soluble sugar content, and osmolality decreased over the first 6 h and remained constant thereafter, contrasting with their continued increases in the untreated cultures. The rate of sucrose uptake, measured by radio-tracer, was reduced by approximately 60% within 3 h of treatment. Aluminium also inhibited glucose uptake. In an aluminium-tolerant cell line (ALT301) isogenic to SL, all of the above-mentioned changes in water relations occurred and tolerance emerged only after 6 h and appeared to involve the suppression of reactive oxygen species. Further separating the effects of aluminium on elongation and cell survival, sucrose starvation for 18 h inhibited elongation and caused similar changes in cellular osmolality but stimulated the production of neither reactive oxygen species nor callose and did not cause cell death. We propose that the inhibition of sucrose uptake is a mechanism whereby aluminium inhibits elongation, but does not account for the induction of cell death. PMID:20219776

  6. Novel FGF8 Mutations Associated with Recessive Holoprosencephaly, Craniofacial Defects, and Hypothalamo-Pituitary Dysfunction

    Science.gov (United States)

    McCabe, Mark J.; Gaston-Massuet, Carles; Tziaferi, Vaitsa; Gregory, Louise C.; Alatzoglou, Kyriaki S.; Signore, Massimo; Puelles, Eduardo; Gerrelli, Dianne; Farooqi, I. Sadaf; Raza, Jamal; Walker, Joanna; Kavanaugh, Scott I.; Tsai, Pei-San; Pitteloud, Nelly; Martinez-Barbera, Juan-Pedro

    2011-01-01

    Context: Fibroblast growth factor (FGF) 8 is important for GnRH neuronal development with human mutations resulting in Kallmann syndrome. Murine data suggest a role for Fgf8 in hypothalamo-pituitary development; however, its role in the etiology of wider hypothalamo-pituitary dysfunction in humans is unknown. Objective: The objective of this study was to screen for FGF8 mutations in patients with septo-optic dysplasia (n = 374) or holoprosencephaly (HPE)/midline clefts (n = 47). Methods: FGF8 was analyzed by PCR and direct sequencing. Ethnically matched controls were then screened for mutated alleles (n = 480–686). Localization of Fgf8/FGF8 expression was analyzed by in situ hybridization in developing murine and human embryos. Finally, Fgf8 hypomorphic mice (Fgf8loxPNeo/−) were analyzed for the presence of forebrain and hypothalamo-pituitary defects. Results: A homozygous p.R189H mutation was identified in a female patient of consanguineous parentage with semilobar HPE, diabetes insipidus, and TSH and ACTH insufficiency. Second, a heterozygous p.Q216E mutation was identified in a female patient with an absent corpus callosum, hypoplastic optic nerves, and Moebius syndrome. FGF8 was expressed in the ventral diencephalon and anterior commissural plate but not in Rathke's pouch, strongly suggesting early onset hypothalamic and corpus callosal defects in these patients. This was consolidated by significantly reduced vasopressin and oxytocin staining neurons in the hypothalamus of Fgf8 hypomorphic mice compared with controls along with variable hypothalamo-pituitary defects and HPE. Conclusion: We implicate FGF8 in the etiology of recessive HPE and potentially septo-optic dysplasia/Moebius syndrome for the first time to our knowledge. Furthermore, FGF8 is important for the development of the ventral diencephalon, hypothalamus, and pituitary. PMID:21832120

  7. Reversible splenial lesion syndrome: two cases report and review of literature

    Directory of Open Access Journals (Sweden)

    Xu-ming FANG

    2014-07-01

    Full Text Available Objective To report 2 cases of reversible splenial lesion syndrome (RESLES and to summarize some key points in diagnosis and treatment of this disease.  Methods The pathogenesis, clinical presentations, neuroimaging features and outcomes of 2 cases with RESLES were retrospectively analyzed and related literature was reviewed.  Results Two patients, including a 24-year-old female and an 18-year-old male, presented with sudden-onset neurologic symptoms, which became prominent after the initiation of an upper respiratory infection. Both patients were previously healthy and had no history of seizure, usage of antiepileptic drugs, or any type of vaccination during the last 2 years. Case 1 just presented with non-vertiginous dizziness. However, Case 2 presented symptoms such as dysphrenia, fever, rigidity, tremor, leukocytosis and creatine kinase (CK elevation. Their clinical presentations were nonspecific, without evidence of callosal disconnection syndrome. They were treated with corticosteroids. Clinically, both patients were greatly improved after 14 and 21 days. Cranial MRI showed an isolated lesion centered in the splenium of the corpus callosum. The lesions were round-shaped without contrast enhancement, and disappeared after complete remission of the underlying disease.  Conclusions To our knowledge and according to previous reports, RESLES is a distinct clinicoradiological syndrome of varied etiology. In addition to sudden withdrawal of antiepileptic drugs and infection, RESLES can be caused by neuroleptic malignant syndrome (NMS. The outcome of the above mentioned cases supports the opinion that prognosis depends on the underlying disorder, but not on the presence or absence of the splenial lesion. doi: 10.3969/j.issn.1672-6731.2014.07.007

  8. Pathogen development and host responses to Plasmopara viticola in resistant and susceptible grapevines: an ultrastructural study.

    Science.gov (United States)

    Yin, Xiao; Liu, Rui-Qi; Su, Hang; Su, Li; Guo, Yu-Rui; Wang, Zi-Jia; Du, Wei; Li, Mei-Jie; Zhang, Xi; Wang, Yue-Jin; Liu, Guo-Tian; Xu, Yan

    2017-01-01

    The downy mildew disease in grapevines is caused by Plasmopara viticola. This disease poses a serious threat wherever viticulture is practiced. Wild Vitis species showing resistance to P. viticola offer a promising pathway to develop new grapevine cultivars resistant to P. viticola which will allow reduced use of environmentally unfriendly fungicides. Here, transmission and scanning microscopy was used to compare the resistance responses to downy mildew of three resistant genotypes of V. davidii var. cyanocarpa, V. piasesezkii and V. pseudoreticulata and the suceptible V. vinifera cultivar 'Pinot Noir'. Following inoculation with sporangia of P. viticola isolate 'YL' on V. vinifera cv. 'Pinot Noir', the infection was characterized by a rapid spread of intercellular hyphae, a high frequency of haustorium formation within the host's mesophyll cells, the production of sporangia and by the absence of host-cell necrosis. In contrast zoospores were collapsed in the resistant V. pseudoreticulata 'Baihe-35-1', or secretions appeared arround stomata at the beginning of the infection period in V. davidii var. cyanocarpa 'Langao-5' and V. piasezkii 'Liuba-8'. The main characteristics of the resistance responses were the rapid depositions of callose and the appearance of empty hyphae and the plasmolysis of penetrated tissue. Moreover, collapsed haustoria were observed in V. davidii var. cyanocarpa 'Langao-5' at 5 days post inoculation (dpi) and in V. piasezkii 'Liuba-8' at 7 dpi. Lastly, necrosis extended beyond the zone of restricted colonization in all three resistant genotypes. Sporangia were absent in V. piasezkii 'Liuba-8' and greatly decreased in V. davidii var. cyanocarpa 'Langao-5' and in V. pseudoreticulata 'Baihe-35-1' compared with in V. vinifera cv. 'Pinot Noir'. Overall, these results provide insights into the cellular biological basis of the incompatible interactions between the pathogen and the host. They indicate a number of several resistant Chinese wild

  9. Spatial and temporal profiles of growth factor expression during CNS demyelination reveal the dynamics of repair priming.

    Directory of Open Access Journals (Sweden)

    Viktoria Gudi

    Full Text Available Demyelination is the cause of disability in various neurological disorders. It is therefore crucial to understand the molecular regulation of oligodendrocytes, the myelin forming cells in the CNS. Growth factors are known to be essential for the development and maintenance of oligodendrocytes and are involved in the regulation of glial responses in various pathological conditions. We employed the well established murine cuprizone model of toxic demyelination to analyze the expression of 13 growth factors in the CNS during de- and remyelination. The temporal mRNA expression profile during demyelination and the subsequent remyelination were analyzed separately in the corpus callosum and cerebral cortex using laser microdissection and real-time PCR techniques. During demyelination a similar pattern of growth factor mRNA expression was observed in both areas with a strong up-regulation of NRG1 and GDNF and a slight increase of CNTF in the first week of cuprizone treatment. HGF, FGF-2, LIF, IGF-I, and TGF-ß1 were up-regulated mainly during peak demyelination. In contrast, during remyelination there were regional differences in growth factor mRNA expression levels. GDNF, CNTF, HGF, FGF-2, and BDNF were elevated in the corpus callosum but not in the cortex, suggesting tissue differences in the molecular regulation of remyelination in the white and grey matter. To clarify the cellular source we isolated microglia from the cuprizone lesions. GDNF, IGF-1, and FGF mRNA were detected in the microglial fraction with a temporal pattern corresponding to that from whole tissue PCR. In addition, immunohistochemical analysis revealed IGF-1 protein expression also in the reactive astrocytes. CNTF was located in astrocytes. This study identified seven different temporal expression patterns for growth factors in white and grey matter and demonstrated the importance of early tissue priming and exact orchestration of different steps during callosal and cortical de

  10. Neural circuitry at age 6 months associated with later repetitive behavior and sensory responsiveness in autism.

    Science.gov (United States)

    Wolff, Jason J; Swanson, Meghan R; Elison, Jed T; Gerig, Guido; Pruett, John R; Styner, Martin A; Vachet, Clement; Botteron, Kelly N; Dager, Stephen R; Estes, Annette M; Hazlett, Heather C; Schultz, Robert T; Shen, Mark D; Zwaigenbaum, Lonnie; Piven, Joseph

    2017-01-01

    Restricted and repetitive behaviors are defining features of autism spectrum disorder (ASD). Under revised diagnostic criteria for ASD, this behavioral domain now includes atypical responses to sensory stimuli. To date, little is known about the neural circuitry underlying these features of ASD early in life. Longitudinal diffusion tensor imaging data were collected from 217 infants at high familial risk for ASD. Forty-four of these infants were diagnosed with ASD at age 2. Targeted cortical, cerebellar, and striatal white matter pathways were defined and measured at ages 6, 12, and 24 months. Dependent variables included the Repetitive Behavior Scale-Revised and the Sensory Experiences Questionnaire. Among children diagnosed with ASD, repetitive behaviors and sensory response patterns were strongly correlated, even when accounting for developmental level or social impairment. Longitudinal analyses indicated that the genu and cerebellar pathways were significantly associated with both repetitive behaviors and sensory responsiveness but not social deficits. At age 6 months, fractional anisotropy in the genu significantly predicted repetitive behaviors and sensory responsiveness at age 2. Cerebellar pathways significantly predicted later sensory responsiveness. Exploratory analyses suggested a possible disordinal interaction based on diagnostic status for the association between fractional anisotropy and repetitive behavior. Our findings suggest that restricted and repetitive behaviors contributing to a diagnosis of ASD at age 2 years are associated with structural properties of callosal and cerebellar white matter pathways measured during infancy and toddlerhood. We further identified that repetitive behaviors and unusual sensory response patterns co-occur and share common brain-behavior relationships. These results were strikingly specific given the absence of association between targeted pathways and social deficits.

  11. Photoassimilation, Assimilate Translocation and Plasmodesmal Biogenesis in the Source Leaves of Arabidopsis thaliana Grown Under an Increased Atmospheric CO2 Concentration

    Science.gov (United States)

    Duan, Zhongrui; Homma, Ayumi; Kobayashi, Megumi; Nagata, Noriko; Kaneko, Yasuko; Fujiki, Yuki; Nishida, Ikuo

    2014-01-01

    Using 18-day-old Arabidopsis thaliana seedlings grown under increased (780 p.p.m., experimental plants) or ambient (390 p.p.m., control plants) CO2 conditions, we evaluated 14CO2 photoassimilation in and translocation from representative source leaves. The total 14CO2 photoassimilation amounts increased in the third leaves of the experimental plants in comparison with that found for the third leaves of the control plants, but the rates were comparable for the first leaves of the two groups. In contrast, translocation of labeled assimilates doubled in the first leaves of the experimental group, whereas translocation was, at best, passively enhanced even though photoassimilation increased in their third leaves. The transcript levels of the companion cell-specific sucrose:H+ symporter gene SUC2 were not significantly affected in the two groups of plants, whereas those of the sucrose effluxer gene SWEET12 and the sieve element-targeted sucrose:H+ symporter gene SUT4 were up-regulated in the experimental plants, suggesting up-regulation of SUT4-dependent apoplastic phloem loading. Compared with SUC2, SUT4 is a minor component that is expressed in companion cells but functions in sieve elements after transfer through plasmodesmata. The number of aniline blue-stained spots for plasmodesma-associated callose in the midrib wall increased in the first leaf of the experimental plants but was comparable in the third leaf between the experimental and control plants. These results suggest that A. thaliana responds to greater than normal concentrations of CO2 differentially in the first and third leaves in regards to photoassimilation, assimilate translocation and plasmodesmal biogenesis. PMID:24406629

  12. Evolutionary appearance of von Economo's neurons in the mammalian cerebral cortex.

    Science.gov (United States)

    Cauda, Franco; Geminiani, Giuliano Carlo; Vercelli, Alessandro

    2014-01-01

    von Economo's neurons (VENs) are large, spindle-shaped projection neurons in layer V of the frontoinsular (FI) cortex, and the anterior cingulate cortex. During human ontogenesis, the VENs can first be differentiated at late stages of gestation, and increase in number during the first eight postnatal months. VENs have been identified in humans, chimpanzee, bonobos, gorillas, orangutan and, more recently, in the macaque. Their distribution in great apes seems to correlate with human-like social cognitive abilities and self-awareness. VENs are also found in whales, in a number of different cetaceans, and in the elephant. This phylogenetic distribution may suggest a correlation among the VENs, brain size and the "social brain." VENs may be involved in the pathogenesis of specific neurological and psychiatric diseases, such as autism, callosal agenesis and schizophrenia. VENs are selectively affected in a behavioral variant of frontotemporal dementia in which empathy, social awareness and self-control are seriously compromised, thus associating VENs with the social brain. However, the presence of VENs has also been related to special functions such as mirror self-recognition. Areas containing VENs have been related to motor awareness or sense-of-knowing, discrimination between self and other, and between self and the external environment. Along this line, VENs have been related to the "global Workspace" architecture: in accordance the VENs have been correlated to emotional and interoceptive signals by providing fast connections (large axons = fast communication) between salience-related insular and cingulate and other widely separated brain areas. Nevertheless, the lack of a characterization of their physiology and anatomical connectivity allowed only to infer their functional role based on their location and on the functional magnetic resonance imaging data. The recent finding of VENs in the anterior insula of the macaque opens the way to new insights and experimental

  13. Evolutionary appearance of von Economo’s neurons in the mammalian cerebral cortex

    Science.gov (United States)

    Cauda, Franco; Geminiani, Giuliano Carlo; Vercelli, Alessandro

    2014-01-01

    von Economo’s neurons (VENs) are large, spindle-shaped projection neurons in layer V of the frontoinsular (FI) cortex, and the anterior cingulate cortex. During human ontogenesis, the VENs can first be differentiated at late stages of gestation, and increase in number during the first eight postnatal months. VENs have been identified in humans, chimpanzee, bonobos, gorillas, orangutan and, more recently, in the macaque. Their distribution in great apes seems to correlate with human-like social cognitive abilities and self-awareness. VENs are also found in whales, in a number of different cetaceans, and in the elephant. This phylogenetic distribution may suggest a correlation among the VENs, brain size and the “social brain.” VENs may be involved in the pathogenesis of specific neurological and psychiatric diseases, such as autism, callosal agenesis and schizophrenia. VENs are selectively affected in a behavioral variant of frontotemporal dementia in which empathy, social awareness and self-control are seriously compromised, thus associating VENs with the social brain. However, the presence of VENs has also been related to special functions such as mirror self-recognition. Areas containing VENs have been related to motor awareness or sense-of-knowing, discrimination between self and other, and between self and the external environment. Along this line, VENs have been related to the “global Workspace” architecture: in accordance the VENs have been correlated to emotional and interoceptive signals by providing fast connections (large axons = fast communication) between salience-related insular and cingulate and other widely separated brain areas. Nevertheless, the lack of a characterization of their physiology and anatomical connectivity allowed only to infer their functional role based on their location and on the functional magnetic resonance imaging data. The recent finding of VENs in the anterior insula of the macaque opens the way to new insights and

  14. Relevance of non-specific MRI features in multiple system atrophy.

    Science.gov (United States)

    Pradhan, Sunil; Tandon, Ruchika

    2017-08-01

    Rarity of specific MRI features like 'hot-cross bun' sign and 'hyperintense putamen rim' reduce diagnostic utility of MRI in MSA. We therefore, studied some non-specific MRI features in addition to the specific ones, to find their diagnostic utility. Clinical and MRI features of 53 indoor and outdoor patients with MSA were analyzed in the context of its Parkinsonian (MSA-P) and cerebellar (MSA-C) variants. Of 53 cases (mean age: 59.53±9.74years), 16 (30.2%) had MSA-C and 37 (69.8%) had MSA-P. Midbrain atrophy was found in 37 (69.8%) MSA patients (70.3% of MSA-P and 68.8% of MSA-C), cerebellar atrophy in 45 (84.9%) MSA patients (81.1% of MSA-P and 93.8% of MSA-C), 'hot-cross bun' sign in 13 (24.5%) MSA patients (27% of MSA-P and 18.8% of MSA-C), hyperintense putamen rim in 19 (35.8%) MSA patients (37.8% of MSA-P and 31.3% of MSA-C) and corpus callosal atrophy in 39 (73.6%) MSA patients (75.7% of MSA-P and 68.8% MSA-C). The midbrain atrophy was mainly lateral tegmental and resembled a positive 'Morning glory' sign in 16 (30.2%). "Hot cross bun" sign and "hyperintense putamen rim" sign were rarely seen in MSA. Combination of mid brain atrophy, corpus callosum atrophy and cerebellar atrophy was more commonly observed in both MSA-C and MSA-P and may be taken as of diagnostic significance. Copyright © 2017. Published by Elsevier B.V.

  15. High throughput transcriptome analysis of coffee reveals prehaustorial resistance in response to Hemileia vastatrix infection.

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    Florez, Juan Carlos; Mofatto, Luciana Souto; do Livramento Freitas-Lopes, Rejane; Ferreira, Sávio Siqueira; Zambolim, Eunize Maciel; Carazzolle, Marcelo Falsarella; Zambolim, Laércio; Caixeta, Eveline Teixeira

    2017-12-01

    We provide a transcriptional profile of coffee rust interaction and identified putative up regulated resistant genes Coffee rust disease, caused by the fungus Hemileia vastatrix, is one of the major diseases in coffee throughout the world. The use of resistant cultivars is considered to be the most effective control strategy for this disease. To identify candidate genes related to different mechanism defense in coffee, we present a time-course comparative gene expression profile of Caturra (susceptible) and Híbrido de Timor (HdT, resistant) in response to H. vastatrix race XXXIII infection. The main objectives were to obtain a global overview of transcriptome in both interaction, compatible and incompatible, and, specially, analyze up-regulated HdT specific genes with inducible resistant and defense signaling pathways. Using both Coffea canephora as a reference genome and de novo assembly, we obtained 43,159 transcripts. At early infection events (12 and 24 h after infection), HdT responded to the attack of H. vastatrix with a larger number of up-regulated genes than Caturra, which was related to prehaustorial resistance. The genes found in HdT at early hours were involved in receptor-like kinases, response ion fluxes, production of reactive oxygen species, protein phosphorylation, ethylene biosynthesis and callose deposition. We selected 13 up-regulated HdT-exclusive genes to validate by real-time qPCR, which most of them confirmed their higher expression in HdT than in Caturra at early stage of infection. These genes have the potential to assist the development of new coffee rust control strategies. Collectively, our results provide understanding of expression profiles in coffee-H. vastatrix interaction over a time course in susceptible and resistant coffee plants.

  16. A single amino acid insertion in the WRKY domain of the Arabidopsis TIR-NBS-LRR-WRKY-type disease resistance protein SLH1 (sensitive to low humidity 1) causes activation of defense responses and hypersensitive cell death.

    Science.gov (United States)

    Noutoshi, Yoshiteru; Ito, Takuya; Seki, Motoaki; Nakashita, Hideo; Yoshida, Shigeo; Marco, Yves; Shirasu, Ken; Shinozaki, Kazuo

    2005-09-01

    In this study we characterized the sensitive to low humidity 1 (slh1) mutant of Arabidopsis ecotype No-0 which exhibits normal growth on agar plate medium but which on transfer to soil shows growth arrest and development of necrotic lesions. cDNA microarray hybridization and RNA gel blot analysis revealed that genes associated with activation of disease resistance were upregulated in the slh1 mutants in response to conditions of low humidity. Furthermore, the slh1 mutants accumulate callose, autofluorescent compounds and salicylic acid (SA). We demonstrate that SA is required for the slh1 phenotype but not PAD4 or NPR1. SLH1 was isolated by map-based cloning and it encodes a resistance (R)-like protein consisting of a domain with Toll and interleukin-1 receptor homology (TIR), a nucleotide-binding domain (NB), leucine-rich repeats (LRR) and a carboxy-terminal WRKY domain. SLH1 is identical to the R gene RRS1-R of the Arabidopsis ecotype Nd-1, a gene which confers resistance to the bacterial pathogen Ralstonia solanacearum GMI1000 and also functions as an R gene to this pathogen in No-0. We identified a 3 bp insertion mutation in slh1 that results in the addition of a single amino acid in the WRKY domain; thereby impairing its DNA-binding activity. Our data suggest that SLH1 disease resistance signaling may be negatively regulated by its WRKY domain in the R protein and that the constitutive defense activation conferred by the slh1 mutation is inhibited by conditions of high humidity.

  17. Abnormal white matter properties in adolescent girls with anorexia nervosa

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    Katherine E. Travis

    2015-01-01

    Full Text Available Anorexia nervosa (AN is a serious eating disorder that typically emerges during adolescence and occurs most frequently in females. To date, very few studies have investigated the possible impact of AN on white matter tissue properties during adolescence, when white matter is still developing. The present study evaluated white matter tissue properties in adolescent girls with AN using diffusion MRI with tractography and T1 relaxometry to measure R1 (1/T1, an index of myelin content. Fifteen adolescent girls with AN (mean age = 16.6 years ± 1.4 were compared to fifteen age-matched girls with normal weight and eating behaviors (mean age = 17.1 years ± 1.3. We identified and segmented 9 bilateral cerebral tracts (18 and 8 callosal fiber tracts in each participant's brain (26 total. Tract profiles were generated by computing measures for fractional anisotropy (FA and R1 along the trajectory of each tract. Compared to controls, FA in the AN group was significantly decreased in 4 of 26 white matter tracts and significantly increased in 2 of 26 white matter tracts. R1 was significantly decreased in the AN group compared to controls in 11 of 26 white matter tracts. Reduced FA in combination with reduced R1 suggests that the observed white matter differences in AN are likely due to reductions in myelin content. For the majority of tracts, group differences in FA and R1 did not occur within the same tract. The present findings have important implications for understanding the neurobiological factors underlying white matter changes associated with AN and invite further investigations examining associations between white matter properties and specific physiological, cognitive, social, or emotional functions affected in AN.

  18. Cell Death Control: The Interplay of Apoptosis and Autophagy in the Pathogenicity of Sclerotinia sclerotiorum

    Science.gov (United States)

    Kabbage, Mehdi; Williams, Brett; Dickman, Martin B.

    2013-01-01

    Programmed cell death is characterized by a cascade of tightly controlled events that culminate in the orchestrated death of the cell. In multicellular organisms autophagy and apoptosis are recognized as two principal means by which these genetically determined cell deaths occur. During plant-microbe interactions cell death programs can mediate both resistant and susceptible events. Via oxalic acid (OA), the necrotrophic phytopathogen Sclerotinia sclerotiorum hijacks host pathways and induces cell death in host plant tissue resulting in hallmark apoptotic features in a time and dose dependent manner. OA-deficient mutants are non-pathogenic and trigger a restricted cell death phenotype in the host that unexpectedly exhibits markers associated with the plant hypersensitive response including callose deposition and a pronounced oxidative burst, suggesting the plant can recognize and in this case respond, defensively. The details of this plant directed restrictive cell death associated with OA deficient mutants is the focus of this work. Using a combination of electron and fluorescence microscopy, chemical effectors and reverse genetics, we show that this restricted cell death is autophagic. Inhibition of autophagy rescued the non-pathogenic mutant phenotype. These findings indicate that autophagy is a defense response in this necrotrophic fungus/plant interaction and suggest a novel function associated with OA; namely, the suppression of autophagy. These data suggest that not all cell deaths are equivalent, and though programmed cell death occurs in both situations, the outcome is predicated on who is in control of the cell death machinery. Based on our data, we suggest that it is not cell death per se that dictates the outcome of certain plant-microbe interactions, but the manner by which cell death occurs that is crucial. PMID:23592997

  19. The Metabolite Pathway between Bundle Sheath and Mesophyll: Quantification of Plasmodesmata in Leaves of C3 and C4 Monocots.

    Science.gov (United States)

    Danila, Florence R; Quick, William Paul; White, Rosemary G; Furbank, Robert T; von Caemmerer, Susanne

    2016-06-01

    C4 photosynthesis is characterized by a CO2-concentrating mechanism between mesophyll (M) and bundle sheath (BS) cells of leaves. This generates high metabolic fluxes between these cells, through interconnecting plasmodesmata (PD). Quantification of these symplastic fluxes for modeling studies requires accurate quantification of PD, which has proven difficult using transmission electron microscopy. Our new quantitative technique combines scanning electron microscopy and 3D immunolocalization in intact leaf tissues to compare PD density on cell interfaces in leaves of C3 (rice [Oryza sativa] and wheat [Triticum aestivum]) and C4 (maize [Zea mays] and Setaria viridis) monocot species. Scanning electron microscopy quantification of PD density revealed that C4 species had approximately twice the number of PD per pitfield area compared with their C3 counterparts. 3D immunolocalization of callose at pitfields using confocal microscopy showed that pitfield area per M-BS interface area was 5 times greater in C4 species. Thus, the two C4 species had up to nine times more PD per M-BS interface area (S. viridis, 9.3 PD µm(-2); maize, 7.5 PD µm(-2); rice 1.0 PD µm(-2); wheat, 2.6 PD µm(-2)). Using these anatomical data and measured photosynthetic rates in these C4 species, we have now calculated symplastic C4 acid flux per PD across the M-BS interface. These quantitative data are essential for modeling studies and gene discovery strategies needed to introduce aspects of C4 photosynthesis to C3 crops. © 2016 American Society of Plant Biologists. All rights reserved.

  20. Diffusion tensor imaging detects early cerebral cortex abnormalities in neuronal architecture induced by bilateral neonatal enucleation: An experimental model in the ferret

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    Andrew S Bock

    2010-10-01

    Full Text Available Diffusion tensor imaging (DTI is a technique that non-invasively provides quantitative measures of water translational diffusion, including fractional anisotropy (FA, that are sensitive to the shape and orientation of cellular elements, such as axons, dendrites and cell somas. For several neurodevelopmental disorders, histopathological investigations have identified abnormalities in the architecture of pyramidal neurons at early stages of cerebral cortex development. To assess the potential capability of DTI to detect neuromorphological abnormalities within the developing cerebral cortex, we compare changes in cortical FA with changes in neuronal architecture and connectivity induced by bilateral enucleation at postnatal day 7 (BEP7 in ferrets. We show here that the visual callosal pattern in BEP7 ferrets is more irregular and occupies a significantly greater cortical area compared to controls at adulthood. To determine whether development of the cerebral cortex is altered in BEP7 ferrets in a manner detectable by DTI, cortical FA was compared in control and BEP7 animals on postnatal day 31. Visual cortex, but not rostrally-adjacent non-visual cortex, exhibits higher FA than control animals, consistent with BEP7 animals possessing axonal and dendritic arbors of reduced complexity than age-matched controls. Subsequent to DTI, Golgi staining and analysis methods were used to identify regions, restricted to visual areas, in which the orientation distribution of neuronal processes is significantly more concentrated than in control ferrets. Together, these findings suggest that DTI can be of utility for detecting abnormalities associated with neurodevelopmental disorders at early stages of cerebral cortical development, and that the neonatally-enucleated ferret is a useful animal model system for systematically assessing the potential of this new diagnostic strategy.

  1. Desiccation tolerance in the chlorophyte green alga Ulva compressa: does cell wall architecture contribute to ecological success?

    Science.gov (United States)

    Holzinger, Andreas; Herburger, Klaus; Kaplan, Franziska; Lewis, Louise A

    2015-08-01

    Desiccation leads to structural changes of the inner pectic cell wall layers in Ulva compressa. This contributes to protection against mechanical damage due to desiccation-rehydration cycles. Ulva compressa, characterized by rbcL phylogeny, is a common species in the Mediterranean Sea. Ulva as an intertidal species tolerates repeated desiccation-rehydration cycles in nature; the physiological and structural basis were investigated under experimental conditions here. Desiccation to 73% relative water content (RWC) led to a significant decrease of the maximum quantum yield of photosystem II (F v/F m) to about half of the initial value. A reduction to 48 or 27% RWC caused a more drastic effect and thalli were only able to recover fully from desiccation to 73% RWC. Relative electron transport rates were stimulated at 73% RWC, but decreased significantly at 48 and 27% RWC, respectively. Imaging-PAM analysis demonstrated a homogenous desiccation process within individual thallus discs. The different cell wall layers of U. compressa were characterized by standard staining procedures, i.e. calcofluor white and aniline blue for structural components (cellulose, callose), ruthenium red for pectins and toluidine blue for acidic polysaccharides. Already a reduction to 73% RWC caused severe changes of the cell walls. The inner pectin-rich layers followed the shrinkage process of the cytoplasm, while the outer denser fibrillar layers maintained their shape. In this way, the thalli were not plasmolyzed during water loss, and upon recovery not negatively influenced by any mechanical damage. Transmission electron microscopy corroborated the arrangement of the different layers clearly distinguishable by their texture and electron density. We suggest the flexibility of the pectin-rich cell wall layers as a major contribution to desiccation tolerance in Ulva.

  2. Pseudomonas evades immune recognition of flagellin in both mammals and plants.

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    Bart W Bardoel

    2011-08-01

    Full Text Available The building blocks of bacterial flagella, flagellin monomers, are potent stimulators of host innate immune systems. Recognition of flagellin monomers occurs by flagellin-specific pattern-recognition receptors, such as Toll-like receptor 5 (TLR5 in mammals and flagellin-sensitive 2 (FLS2 in plants. Activation of these immune systems via flagellin leads eventually to elimination of the bacterium from the host. In order to prevent immune activation and thus favor survival in the host, bacteria secrete many proteins that hamper such recognition. In our search for Toll like receptor (TLR antagonists, we screened bacterial supernatants and identified alkaline protease (AprA of Pseudomonas aeruginosa as a TLR5 signaling inhibitor as evidenced by a marked reduction in IL-8 production and NF-κB activation. AprA effectively degrades the TLR5 ligand monomeric flagellin, while polymeric flagellin (involved in bacterial motility and TLR5 itself resist degradation. The natural occurring alkaline protease inhibitor AprI of P. aeruginosa blocked flagellin degradation by AprA. P. aeruginosa aprA mutants induced an over 100-fold enhanced activation of TLR5 signaling, because they fail to degrade excess monomeric flagellin in their environment. Interestingly, AprA also prevents flagellin-mediated immune responses (such as growth inhibition and callose deposition in Arabidopsis thaliana plants. This was due to decreased activation of the receptor FLS2 and clearly demonstrated by delayed stomatal closure with live bacteria in plants. Thus, by degrading the ligand for TLR5 and FLS2, P. aeruginosa escapes recognition by the innate immune systems of both mammals and plants.

  3. Pseudomonas evades immune recognition of flagellin in both mammals and plants.

    Science.gov (United States)

    Bardoel, Bart W; van der Ent, Sjoerd; Pel, Michiel J C; Tommassen, Jan; Pieterse, Corné M J; van Kessel, Kok P M; van Strijp, Jos A G

    2011-08-01

    The building blocks of bacterial flagella, flagellin monomers, are potent stimulators of host innate immune systems. Recognition of flagellin monomers occurs by flagellin-specific pattern-recognition receptors, such as Toll-like receptor 5 (TLR5) in mammals and flagellin-sensitive 2 (FLS2) in plants. Activation of these immune systems via flagellin leads eventually to elimination of the bacterium from the host. In order to prevent immune activation and thus favor survival in the host, bacteria secrete many proteins that hamper such recognition. In our search for Toll like receptor (TLR) antagonists, we screened bacterial supernatants and identified alkaline protease (AprA) of Pseudomonas aeruginosa as a TLR5 signaling inhibitor as evidenced by a marked reduction in IL-8 production and NF-κB activation. AprA effectively degrades the TLR5 ligand monomeric flagellin, while polymeric flagellin (involved in bacterial motility) and TLR5 itself resist degradation. The natural occurring alkaline protease inhibitor AprI of P. aeruginosa blocked flagellin degradation by AprA. P. aeruginosa aprA mutants induced an over 100-fold enhanced activation of TLR5 signaling, because they fail to degrade excess monomeric flagellin in their environment. Interestingly, AprA also prevents flagellin-mediated immune responses (such as growth inhibition and callose deposition) in Arabidopsis thaliana plants. This was due to decreased activation of the receptor FLS2 and clearly demonstrated by delayed stomatal closure with live bacteria in plants. Thus, by degrading the ligand for TLR5 and FLS2, P. aeruginosa escapes recognition by the innate immune systems of both mammals and plants.

  4. A transcriptomics approach uncovers novel roles for poly(ADP-ribosylation in the basal defense response in Arabidopsis thaliana.

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    Amy G Briggs

    Full Text Available Pharmacological inhibition of poly(ADP-ribose polymerase (PARP or loss of Arabidopsis thaliana PARG1 (poly(ADP-ribose glycohydrolase disrupt a subset of plant defenses. In the present study we examined the impact of altered poly(ADP-ribosylation on early gene expression induced by the microbe-associate molecular patterns (MAMPs flagellin (flg22 and EF-Tu (elf18. Stringent statistical analyses and filtering identified 178 genes having MAMP-induced mRNA abundance patterns that were altered by either PARP inhibitor 3-aminobenzamide (3AB or PARG1 knockout. From the identified set of 178 genes, over fifty Arabidopsis T-DNA insertion lines were chosen and screened for altered basal defense responses. Subtle alterations in callose deposition and/or seedling growth in response to those MAMPs were observed in knockouts of At3g55630 (FPGS3, a cytosolic folylpolyglutamate synthetase, At5g15660 (containing an F-box domain, At1g47370 (a TIR-X (Toll-Interleukin Receptor domain, and At5g64060 (a predicted pectin methylesterase inhibitor. Over-represented GO terms for the gene expression study included "innate immune response" for elf18/parg1, highlighting a subset of elf18-activated defense-associated genes whose expression is altered in parg1 plants. The study also allowed a tightly controlled comparison of early mRNA abundance responses to flg22 and elf18 in wild-type Arabidopsis, which revealed many differences. The PARP inhibitor 3-methoxybenzamide (3MB was also used in the gene expression profiling, but pleiotropic impacts of this inhibitor were observed. This transcriptomics study revealed targets for further dissection of MAMP-induced plant immune responses, impacts of PARP inhibitors, and the molecular mechanisms by which poly(ADP-ribosylation regulates plant responses to MAMPs.

  5. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2

    Science.gov (United States)

    Castañeda-Ojeda, María Pilar; Moreno-Pérez, Alba; Ramos, Cayo; López-Solanilla, Emilia

    2017-01-01

    The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E) in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts. PMID:28529516

  6. Label-Free Quantitative Proteomics of Embryogenic and Non-Embryogenic Callus during Sugarcane Somatic Embryogenesis.

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    Angelo Schuabb Heringer

    Full Text Available The development of somatic cells in to embryogenic cells occurs in several stages and ends in somatic embryo formation, though most of these biochemical and molecular changes have yet to be elucidated. Somatic embryogenesis coupled with genetic transformation could be a biotechnological tool to improve potential crop yields potential in sugarcane cultivars. The objective of this study was to observe somatic embryo development and to identify differentially expressed proteins in embryogenic (E and non-embryogenic (NE callus during maturation treatment. E and NE callus were cultured on maturation culture medium supplemented with different concentrations (0.0, 0.75, 1.5 and 2.0 g L(-1 of activated charcoal (AC. Somatic embryo formation and differential protein expression were evaluated at days 0 and 21 using shotgun proteomic analyses. Treatment with 1.5 g L(-1 AC resulted in higher somatic embryo maturation rates (158 somatic embryos in 14 days in E callus but has no effect in NE callus. A total of 752 co-expressed proteins were identified through the SUCEST (The Sugarcane EST Project, including many housekeeping proteins. E callus showed 65 exclusive proteins on day 0, including dehydrogenase, desiccation-related protein, callose synthase 1 and nitric oxide synthase. After 21 days on maturation treatment, 14 exclusive proteins were identified in E callus, including catalase and secreted protein. NE callus showed 23 exclusive proteins on day 0 and 10 exclusive proteins after 21 days on maturation treatment, including many proteins related to protein degradation. The induction of maturation leads to somatic embryo development, which likely depends on the expression of specific proteins throughout the process, as seen in E callus under maturation treatment. On the other hand, some exclusive proteins can also specifically prevent of somatic embryos development, as seen in the NE callus.

  7. Integrative analysis and expression profiling of secondary cell wall genes in C4 biofuel model Setaria italica reveals targets for lignocellulose bioengineering

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    Mehanathan eMuthamilarasan

    2015-11-01

    Full Text Available Several underutilized grasses have excellent potential for use as bioenergy feedstock due to their lignocellulosic biomass. Genomic tools have enabled identification of lignocellulose biosynthesis genes in several sequenced plants. However, the non-availability of whole genome sequence of bioenergy grasses hinders the study on bioenergy genomics and their genomics-assisted crop improvement. Foxtail millet (Setaria italica L.; Si is a model crop for studying systems biology of bioenergy grasses. In the present study, a systematic approach has been used for identification of gene families involved in cellulose (CesA/Csl, callose (Gsl and monolignol biosynthesis (PAL, C4H, 4CL, HCT, C3H, CCoAOMT, F5H, COMT, CCR, CAD and construction of physical map of foxtail millet. Sequence alignment and phylogenetic analysis of identified proteins showed that monolignol biosynthesis proteins were highly diverse, whereas CesA/Csl and Gsl proteins were homologous to rice and Arabidopsis. Comparative mapping of foxtail millet lignocellulose biosynthesis genes with other C4 panicoid genomes revealed maximum homology with switchgrass, followed by sorghum and maize. Expression profiling of candidate lignocellulose genes in response to different abiotic stresses and hormone treatments showed their differential expression pattern, with significant higher expression of SiGsl12, SiPAL2, SiHCT1, SiF5H2 and SiCAD6 genes. Further, due to the evolutionary conservation of grass genomes, the insights gained from the present study could be extrapolated for identifying genes involved in lignocellulose biosynthesis in other biofuel species for further characterization.

  8. Werner syndrome: clinical evaluation of two cases and a novel mutation.

    Science.gov (United States)

    Mansur, A T; Elçioglu, N H; Demirci, G T

    2014-01-01

    Werner syndrome (WS) is a premature aging disorder, inherited in an autosomal recessive pattern and caused by the mutation in the WRN gene. In this report we describe two male patients with negative family history who demonstrate characteristic findings of WS, with different mutations, including one novel mutation. The first case was a 47-year-old man who had been suffering from large, ischemic ulcers on both legs for 7 years. Physical examination revealed a thin and short man with severe wasting of all extremities. He had a high-pitched voice, hoarseness, a characteristic bird-like facies, bilateral cataracts, generalized osteoporosis, hypotrichosis, atrophic and poikilodermic skin, flexion contractures of hands, feet and knees, and soft tissue calcifications. Laboratory investigations revealed anemia, high erythrocyte sedimentation rate, low creatinine clearance, and high liver enzymes. Genetic analysis showed a homozygous novel 1bp-deletion in exon 19 of WRN, 2426/27delG, causing frameshift and protein truncation R809SfsX2, which has not been described before. The second case was a 23-year-old man who was referred for large callosities on both feet, present for 7 years. He complained of weakness, weight loss, wasting of muscles, and early graying of hair. The entire skin was thin, wrinkled and dry. Generalized hypotrichosis, scattered ephelid-like macules, sclerotic fingers, calcinosis cutis on ears, hyperpigmentation on elbows were the other alterations of skin. Skeletal survey revealed osteoporosis. Genetic analysis showed a homozygous known pathogenic splice site mutation c.3460-2A>G, causing skipping of Exon 30 in WRN.

  9. A gene expression analysis of cell wall biosynthetic genes in Malus x domestica infected by 'Candidatus Phytoplasma mali'.

    Science.gov (United States)

    Guerriero, Gea; Giorno, Filomena; Ciccotti, Anna Maria; Schmidt, Silvia; Baric, Sanja

    2012-11-01

    Apple proliferation (AP) represents a serious threat to several fruit-growing areas and is responsible for great economic losses. Several studies have highlighted the key role played by the cell wall in response to pathogen attack. The existence of a cell wall integrity signaling pathway which senses perturbations in the cell wall architecture upon abiotic/biotic stresses and activates specific defence responses has been widely demonstrated in plants. More recently a role played by cell wall-related genes has also been reported in plants infected by phytoplasmas. With the aim of shedding light on the cell wall response to AP disease in the economically relevant fruit-tree Malus × domestica Borkh., we investigated the expression of the cellulose (CesA) and callose synthase (CalS) genes in different organs (i.e., leaves, roots and branch phloem) of healthy and infected symptomatic outdoor-grown trees, sampled over the course of two time points (i.e., spring and autumn 2011), as well as in in vitro micropropagated control and infected plantlets. A strong up-regulation in the expression of cell wall biosynthetic genes was recorded in roots from infected trees. Secondary cell wall CesAs showed up-regulation in the phloem tissue from branches of infected plants, while either a down-regulation of some genes or no major changes were observed in the leaves. Micropropagated plantlets also showed an increase in cell wall-related genes and constitute a useful system for a general assessment of gene expression analysis upon phytoplasma infection. Finally, we also report the presence of several 'knot'-like structures along the roots of infected apple trees and discuss the occurrence of this interesting phenotype in relation to the gene expression results and the modalities of phytoplasma diffusion.

  10. The CSF-1 receptor ligands IL-34 and CSF-1 exhibit distinct developmental brain expression patterns and regulate neural progenitor cell maintenance and maturation

    Science.gov (United States)

    Nandi, Sayan; Gokhan, Solen; Dai, Xu-Ming; Wei, Suwen; Enikolopov, Grigori; Lin, Haishan; Mehler, Mark F.; Stanley, E. Richard

    2012-01-01

    The CSF-1 receptor (CSF-1R) regulates CNS microglial development. However, the localization and developmental roles of this receptor and its ligands, IL-34 and CSF-1, in the brain are poorly understood. Here we show that compared to wild type mice, CSF-1R-deficient (Csf1r−/−) mice have smaller brains of greater mass. They further exhibit an expansion of lateral ventricle size, an atrophy of the olfactory bulb and a failure of midline crossing of callosal axons. In brain, IL-34 exhibited a broader regional expression than CSF-1, mostly without overlap. Expression of IL-34, CSF-1 and the CSF-1R were maximal during early postnatal development. However, in contrast to the expression of its ligands, CSF-1R expression was very low in adult brain. Postnatal neocortical expression showed that CSF-1 was expressed in layer VI, whereas IL-34 was expressed in the meninges and layers II–V. The broader expression of IL-34 is consistent with its previously implicated role in microglial development. The differential expression of CSF-1R ligands, with respect to CSF-1R expression, could reflect their CSF-1R-independent signaling. Csf1r−/− mice displayed increased proliferation and apoptosis of neocortical progenitors and reduced differentiation of specific excitatory neuronal subtypes. Indeed, addition of CSF-1 or IL-34 to microglia-free, CSF-1R-expressing dorsal forebrain clonal cultures, suppressed progenitor self-renewal and enhanced neuronal differentiation. Consistent with a neural developmental role for the CSF-1R, ablation of the Csf1r gene in Nestin-positive neural progenitors led to a smaller brain size, an expanded neural progenitor pool and elevated cellular apoptosis in cortical forebrain. Thus our results also indicate novel roles for the CSF-1R in the regulation of corticogenesis. PMID:22542597

  11. Cell wall biochemical alterations during Agrobacterium-mediated expression of haemagglutinin-based influenza virus-like vaccine particles in tobacco.

    Science.gov (United States)

    Le Mauff, François; Loutelier-Bourhis, Corinne; Bardor, Muriel; Berard, Caroline; Doucet, Alain; D'Aoust, Marc-André; Vezina, Louis-Philippe; Driouich, Azeddine; Couture, Manon M-J; Lerouge, Patrice

    2017-03-01

    Influenza virus-like particles (VLPs) have been shown to induce a safe and potent immune response through both humoral and cellular responses. They represent promising novel influenza vaccines. Plant-based biotechnology allows for the large-scale production of VLPs of biopharmaceutical interest using different model organisms, including Nicotiana benthamiana plants. Through this platform, influenza VLPs bud from the plasma membrane and accumulate between the membrane and the plant cell wall. To design and optimize efficient production processes, a better understanding of the plant cell wall composition of infiltrated tobacco leaves is a major interest for the plant biotechnology industry. In this study, we have investigated the alteration of the biochemical composition of the cell walls of N. benthamiana leaves subjected to abiotic and biotic stresses induced by the Agrobacterium-mediated transient transformation and the resulting high expression levels of influenza VLPs. Results show that abiotic stress due to vacuum infiltration without Agrobacterium did not induce any detectable modification of the leaf cell wall when compared to non infiltrated leaves. In contrast, various chemical changes of the leaf cell wall were observed post-Agrobacterium infiltration. Indeed, Agrobacterium infection induced deposition of callose and lignin, modified the pectin methylesterification and increased both arabinosylation of RG-I side chains and the expression of arabinogalactan proteins. Moreover, these modifications were slightly greater in plants expressing haemagglutinin-based VLP than in plants infiltrated with the Agrobacterium strain containing only the p19 suppressor of silencing. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  12. Addition of Phenylboronic Acid to Malus domestica Pollen Tubes Alters Calcium Dynamics, Disrupts Actin Filaments and Affects Cell Wall Architecture.

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    Kefeng Fang

    Full Text Available A key role of boron in plants is to cross-link the cell wall pectic polysaccharide rhamnogalacturonan-II (RG-II through borate diester linkages. Phenylboronic acid (PBA can form the same reversible ester bonds but cannot cross-link two molecules, so can be used as an antagonist to study the function of boron. This study aimed to evaluate the effect of PBA on apple (Malus domestica pollen tube growth and the underlying regulatory mechanism. We observed that PBA caused an inhibition of pollen germination, tube growth and led to pollen tube morphological abnormalities. Fluorescent labeling, coupled with a scanning ion-selective electrode technique, revealed that PBA induced an increase in extracellular Ca2+ influx, thereby elevating the cytosolic Ca2+ concentration [Ca2+]c and disrupting the [Ca2+]c gradient, which is critical for pollen tube growth. Moreover the organization of actin filaments was severely perturbed by the PBA treatment. Immunolocalization studies and fluorescent labeling, together with Fourier-transform infrared analysis (FTIR suggested that PBA caused an increase in the abundance of callose, de-esterified pectins and arabinogalactan proteins (AGPs at the tip. However, it had no effect on the deposition of the wall polymers cellulose. These effects are similar to those of boron deficiency in roots and other organs, indicating that PBA can induce boron deficiency symptoms. The results provide new insights into the roles of boron in pollen tube development, which likely include regulating [Ca2+]c and the formation of the actin cytoskeleton, in addition to the synthesis and assembly of cell wall components.

  13. Purification and characterization of a novel hypersensitive response-inducing elicitor from Magnaporthe oryzae that triggers defense response in rice.

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    Mingjia Chen

    Full Text Available BACKGROUND: Magnaporthe oryzae, the rice blast fungus, might secrete certain proteins related to plant-fungal pathogen interactions. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we report the purification, characterization, and gene cloning of a novel hypersensitive response-inducing protein elicitor (MoHrip1 secreted by M. oryzae. The protein fraction was purified and identified by de novo sequencing, and the sequence matched the genomic sequence of a putative protein from M. oryzae strain 70-15 (GenBank accession No. XP_366602.1. The elicitor-encoding gene mohrip1 was isolated; it consisted of a 429 bp cDNA, which encodes a polypeptide of 142 amino acids with a molecular weight of 14.322 kDa and a pI of 4.53. The deduced protein, MoHrip1, was expressed in E. coli. And the expression protein collected from bacterium also forms necrotic lesions in tobacco. MoHrip1 could induce the early events of the defense response, including hydrogen peroxide production, callose deposition, and alkalization of the extracellular medium, in tobacco. Moreover, MoHrip1-treated rice seedlings possessed significantly enhanced systemic resistance to M. oryzae compared to the control seedlings. The real-time PCR results indicated that the expression of some pathogenesis-related genes and genes involved in signal transduction could also be induced by MoHrip1. CONCLUSION/SIGNIFICANCE: The results demonstrate that MoHrip1 triggers defense responses in rice and could be used for controlling rice blast disease.

  14. Learning-based prediction of gestational age from ultrasound images of the fetal brain.

    Science.gov (United States)

    Namburete, Ana I L; Stebbing, Richard V; Kemp, Bryn; Yaqub, Mohammad; Papageorghiou, Aris T; Alison Noble, J

    2015-04-01

    We propose an automated framework for predicting gestational age (GA) and neurodevelopmental maturation of a fetus based on 3D ultrasound (US) brain image appearance. Our method capitalizes on age-related sonographic image patterns in conjunction with clinical measurements to develop, for the first time, a predictive age model which improves on the GA-prediction potential of US images. The framework benefits from a manifold surface representation of the fetal head which delineates the inner skull boundary and serves as a common coordinate system based on cranial position. This allows for fast and efficient sampling of anatomically-corresponding brain regions to achieve like-for-like structural comparison of different developmental stages. We develop bespoke features which capture neurosonographic patterns in 3D images, and using a regression forest classifier, we characterize structural brain development both spatially and temporally to capture the natural variation existing in a healthy population (N=447) over an age range of active brain maturation (18-34weeks). On a routine clinical dataset (N=187) our age prediction results strongly correlate with true GA (r=0.98,accurate within±6.10days), confirming the link between maturational progression and neurosonographic activity observable across gestation. Our model also outperforms current clinical methods by ±4.57 days in the third trimester-a period complicated by biological variations in the fetal population. Through feature selection, the model successfully identified the most age-discriminating anatomies over this age range as being the Sylvian fissure, cingulate, and callosal sulci. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  15. A gene expression analysis of cell wall biosynthetic genes in Malus × domestica infected by ‘Candidatus Phytoplasma mali’

    Science.gov (United States)

    Guerriero, Gea; Giorno, Filomena; Ciccotti, Anna Maria; Schmidt, Silvia; Baric, Sanja

    2016-01-01

    Apple proliferation (AP) represents a serious threat to several fruit-growing areas and is responsible for great economic losses. Several studies have highlighted the key role played by the cell wall in response to pathogen attack. The existence of a cell wall integrity signaling pathway which senses perturbations in the cell wall architecture upon abiotic/biotic stresses and activates specific defence responses has been widely demonstrated in plants. More recently a role played by cell wall-related genes has also been reported in plants infected by phytoplasmas. With the aim of shedding light on the cell wall response to AP disease in the economically relevant fruit-tree Malus × domestica Borkh., we investigated the expression of the cellulose (CesA) and callose synthase (CalS) genes in different organs (i.e., leaves, roots and branch phloem) of healthy and infected symptomatic outdoor-grown trees, sampled over the course of two time points (i.e., spring and autumn 2011), as well as in in vitro micropropagated control and infected plantlets. A strong up-regulation in the expression of cell wall biosynthetic genes was recorded in roots from infected trees. Secondary cell wall CesAs showed up-regulation in the phloem tissue from branches of infected plants, while either a down-regulation of some genes or no major changes were observed in the leaves. Micropropagated plantlets also showed an increase in cell wall-related genes and constitute a useful system for a general assessment of gene expression analysis upon phytoplasma infection. Finally, we also report the presence of several ‘knot’-like structures along the roots of infected apple trees and discuss the occurrence of this interesting phenotype in relation to the gene expression results and the modalities of phytoplasma diffusion. PMID:23086810

  16. Corpus callosum thickness in children: an MR pattern-recognition approach on the midsagittal image

    Energy Technology Data Exchange (ETDEWEB)

    Andronikou, Savvas; Pillay, Tanyia; Gabuza, Lungile; Mahomed, Nasreen; Naidoo, Jaishree; Tebogo Hlabangana, Linda [University of the Witwatersrand, Radiology Department, Faculty of Health Sciences, Johannesburg (South Africa); Du Plessis, Vicci [University of KwaZulu-Natal, Radiology Department, Faculty of Health Sciences, Durban (South Africa); Prabhu, Sanjay P. [Harvard Medical School, Department of Radiology, Boston Children' s Hospital, Boston, MA (United States)

    2014-08-31

    Thickening of the corpus callosum is an important feature of development, whereas thinning of the corpus callosum can be the result of a number of diseases that affect development or cause destruction of the corpus callosum. Corpus callosum thickness reflects the volume of the hemispheres and responds to changes through direct effects or through Wallerian degeneration. It is therefore not only important to evaluate the morphology of the corpus callosum for congenital anomalies but also to evaluate the thickness of specific components or the whole corpus callosum in association with other findings. The goal of this pictorial review is raise awareness that the thickness of the corpus callosum can be a useful feature of pathology in pediatric central nervous system disease and must be considered in the context of the stage of development of a child. Thinning of the corpus callosum can be primary or secondary, and generalized or focal. Primary thinning is caused by abnormal or failed myelination related to the hypomyelinating leukoencephalopathies, metabolic disorders affecting white matter, and microcephaly. Secondary thinning of the corpus callosum can be caused by diffuse injury such as hypoxic-ischemic encephalopathy, human immunodeficiency virus (HIV) encephalopathy, hydrocephalus, dysmyelinating conditions and demyelinating conditions. Focal disturbance of formation or focal injury also causes localized thinning, e.g., callosal dysgenesis, metabolic disorders with localized effects, hypoglycemia, white matter injury of prematurity, HIV-related atrophy, infarction and vasculitis, trauma and toxins. The corpus callosum might be too thick because of a primary disorder in which the corpus callosum finding is essential to diagnosis; abnormal thickening can also be secondary to inflammation, infection and trauma. (orig.)

  17. Xanthomonas campestris attenuates virulence by sensing light through a bacteriophytochrome photoreceptor.

    Science.gov (United States)

    Bonomi, Hernán R; Toum, Laila; Sycz, Gabriela; Sieira, Rodrigo; Toscani, Andrés M; Gudesblat, Gustavo E; Leskow, Federico C; Goldbaum, Fernando A; Vojnov, Adrián A; Malamud, Florencia

    2016-11-01

    Phytochromes constitute a major photoreceptor family found in plants, algae, fungi, and prokaryotes, including pathogens. Here, we report that Xanthomonas campestris pv. campestris (Xcc), the causal agent of black rot disease which affects cruciferous crops worldwide, codes for a functional bacteriophytochrome (XccBphP). XccBphP possesses an N-terminal PAS2-GAF-PHY photosensory domain triad and a C-terminal PAS9 domain as its output module. Our results show that illumination of Xcc, prior to plant infection, attenuates its virulence in an XccBphP-dependent manner. Moreover, in response to light, XccBphP downregulates xanthan exopolysaccharide production and biofilm formation, two known Xcc virulence factors. Furthermore, the XccbphP null mutant shows enhanced virulence, similar to that of dark-adapted Xcc cultures. Stomatal aperture regulation and callose deposition, both well-established plant defense mechanisms against bacterial pathogens, are overridden by the XccbphP strain. Additionally, an RNA-Seq analysis reveals that far-red light or XccBphP overexpression produces genomewide transcriptional changes, including the inhibition of several Xcc virulence systems. Our findings indicate that Xcc senses light through XccBphP, eliciting bacterial virulence attenuation via downregulation of bacterial virulence factors. The capacity of XccBphP to respond to light both in vitro and in vivo was abolished by a mutation on the conserved Cys13 residue. These results provide evidence for a novel bacteriophytochrome function affecting an infectious process. © 2016 The Authors.

  18. Quantifying the effects of normal ageing on white matter structure using unsupervised tract shape modelling.

    Science.gov (United States)

    Bastin, Mark E; Muñoz Maniega, Susana; Ferguson, Karen J; Brown, Laura J; Wardlaw, Joanna M; MacLullich, Alasdair M J; Clayden, Jonathan D

    2010-05-15

    Quantitative tractography may provide insights into regional heterogeneity of changes in white matter structure in normal ageing. Here we examine how brain atrophy and white matter lesions affect correlations between tract shape, tract integrity and age in a range of frontal and non-frontal tracts in 90 non-demented subjects aged over 65 years using an enhanced version of probabilistic neighbourhood tractography. This novel method for automatic single seed point placement employs unsupervised learning and streamline selection to provide reliable and accurate tract segmentation, whilst also indicating how the shape of an individual tract compares to that of a predefined reference tract. There were significant negative correlations between tract shape similarity to reference tracts derived from a young brain white matter atlas and age in genu and splenium of corpus callosum. Controlling for intracranial and lateral ventricle volume, the latter of which increased significantly with age, attenuated these correlations by 40% and 84%, respectively, indicating that this age-related change in callosal tract topology is significantly mediated by global atrophy and ventricular enlargement. In accordance with the "frontal ageing" hypothesis, there was a significant positive correlation between mean diffusivity (D) and age, and a significant negative correlation between fractional anisotropy (FA) and age in corpus callosum genu; correlations not seen in splenium. Significant positive correlations were also observed between D and age in bilateral cingulum cingulate gyri, uncinate fasciculi and right corticospinal tract. This pattern of correlations was not, however, reproduced when those subjects with significant white matter lesion load were analyzed separately from those without. These data therefore suggest that brain atrophy and white matter lesions play a significant role in driving regional patterns of age-related changes in white matter tract shape and integrity

  19. A Mutation in the Catalytic Subunit of the Glycosylphosphatidylinositol Transamidase Disrupts Growth, Fertility, and Stomata Formation1[OPEN

    Science.gov (United States)

    2016-01-01

    GPI-anchored proteins (GPI-APs) are essential for plant growth and development; knockout mutations in enzymes responsible for anchor biosynthesis or attachment are gametophyte or embryo lethal. In a genetic screen targeted to identify genes regulating stomata formation, we discovered a missense mutation in the Arabidopsis (Arabidopsis thaliana) homolog of GPI8/PIG-K, a Cys protease that transfers an assembled GPI anchor to proteins. The Arabidopsis genome has a single copy of AtGPI8, and the atgpi8-1 mutation reduces the efficiency of this enzyme, leading to reduced accumulation of GPI-anchored proteins. While the atgpi8-1 mutation strongly disrupts plant growth, it is not lethal. Phenotypic analysis of atgpi8-1 mutants suggests that GPI-APs are important for root and shoot growth, stomata formation, apical dominance, transition to flowering, and male gametophyte viability. In addition, atgpi8-1 mutants accumulate higher levels of callose and have reduced plasmodesmata permeability. Genetic interactions of atgpi8-1 with mutations in ERECTA family (ERf) genes suggest the existence of a GPI-AP in a branch of the ERf signaling pathway that regulates stomata formation. Activation of the ERf signal transduction cascade by constitutively active YODA rescues stomata clustering in atgpi8-1, indicating that a GPI-AP functions upstream of the MAP kinase cascade. TOO MANY MOUTHS (TMM) is a receptor-like protein that is able to form heterodimers with ERfs. Our analysis demonstrates that tmm-1 is epistatic to atgpi8-1, indicating that either TMM is a GPI-AP or there is another GPI-AP regulating stomata development whose function is dependent upon TMM. PMID:27208238

  20. A Mutation in the Catalytic Subunit of the Glycosylphosphatidylinositol Transamidase Disrupts Growth, Fertility, and Stomata Formation.

    Science.gov (United States)

    Bundy, Mark G R; Kosentka, Pawel Z; Willet, Alaina H; Zhang, Liang; Miller, Emily; Shpak, Elena D

    2016-06-01

    GPI-anchored proteins (GPI-APs) are essential for plant growth and development; knockout mutations in enzymes responsible for anchor biosynthesis or attachment are gametophyte or embryo lethal. In a genetic screen targeted to identify genes regulating stomata formation, we discovered a missense mutation in the Arabidopsis (Arabidopsis thaliana) homolog of GPI8/PIG-K, a Cys protease that transfers an assembled GPI anchor to proteins. The Arabidopsis genome has a single copy of AtGPI8, and the atgpi8-1 mutation reduces the efficiency of this enzyme, leading to reduced accumulation of GPI-anchored proteins. While the atgpi8-1 mutation strongly disrupts plant growth, it is not lethal. Phenotypic analysis of atgpi8-1 mutants suggests that GPI-APs are important for root and shoot growth, stomata formation, apical dominance, transition to flowering, and male gametophyte viability. In addition, atgpi8-1 mutants accumulate higher levels of callose and have reduced plasmodesmata permeability. Genetic interactions of atgpi8-1 with mutations in ERECTA family (ERf) genes suggest the existence of a GPI-AP in a branch of the ERf signaling pathway that regulates stomata formation. Activation of the ERf signal transduction cascade by constitutively active YODA rescues stomata clustering in atgpi8-1, indicating that a GPI-AP functions upstream of the MAP kinase cascade. TOO MANY MOUTHS (TMM) is a receptor-like protein that is able to form heterodimers with ERfs. Our analysis demonstrates that tmm-1 is epistatic to atgpi8-1, indicating that either TMM is a GPI-AP or there is another GPI-AP regulating stomata development whose function is dependent upon TMM. © 2016 American Society of Plant Biologists. All Rights Reserved.

  1. Aluminum ions induce oat protoplasts to produce an extracellular (1 yields 3). beta. -D-glucan

    Energy Technology Data Exchange (ETDEWEB)

    Schaeffer, H.J.; Walton, J.D. (Michigan State Univ., East Lansing (USA))

    1990-09-01

    Aluminum chloride induced mesophyll protoplasts of oat (Avena sativa) to produce an extracellular polysaccharide (EPS). EPS induced by AlCl{sub 3} appeared identical to that produced in response to the phytotoxin victorin. Al ions at 1 millimolar were toxic to protoplasts, but maximum EPS production occurred at a sublethal concentration of 200 micromolar, assayed at pH 6.0. As measured by incorporation of ({sup 14}C)glucose, AlCl{sub 3} stimulated EPS production 10- to 15-fold. Pretreatment of protoplasts with cycloheximide prevented EPS production but not cell death in response to AlCl{sub 3}, indicating that protein synthesis was necessary for EPS production but not for the phytotoxicity of Al ions. The trivalent salts of Y, Yb, Gd, and In also induced EPS production but those of Sc, Fe, Ga, Cr, and La did not. Mesophyll protoplasts from an acid-soil tolerant oat cultivar produced less EPS in response to AlCl{sub 3} than the acid-soil sensitive cultivar Fla 501. EPS was also produced by wheat (Triticum aestivum) and barley (Hordeum vulgare) protoplasts in response to AlCl{sub 3}. An Al-tolerant cultivar of wheat, Atlas, produced less EPS than an Al-sensitive cultivar, Scout, but an Al-tolerant cultivar of barley, Dayton, produced more than the Al-sensitive cultivar Kearney. Therefore, production of EPS by protoplasts in response to Al ions did not appear to be related to Al ion tolerance at the level of whole plants. EPS fluoresced in the presence of Calcofluor and Sirofluor and was degraded by purified laminarinase ((1{yields}3){beta}-D-glucanase) but did not pectinase (polygalacturonase). EPS was composed solely of glucose in 1{yields}3 linkages; hence it is a (1{yields}3){beta}-D-glucan (callose).

  2. A Secreted MIF Cytokine Enables Aphid Feeding and Represses Plant Immune Responses.

    Science.gov (United States)

    Naessens, Elodie; Dubreuil, Géraldine; Giordanengo, Philippe; Baron, Olga Lucia; Minet-Kebdani, Naïma; Keller, Harald; Coustau, Christine

    2015-07-20

    Aphids attack virtually all plant species and cause serious crop damages in agriculture. Despite their dramatic impact on food production, little is known about the molecular processes that allow aphids to exploit their host plants. To date, few aphid salivary proteins have been identified that are essential for aphid feeding, and their nature and function remain largely unknown. Here, we show that a macrophage migration inhibitory factor (MIF) is secreted in aphid saliva. In vertebrates, MIFs are important pro-inflammatory cytokines regulating immune responses. MIF proteins are also secreted by parasites of vertebrates, including nematodes, ticks, and protozoa, and participate in the modulation of host immune responses. The finding that a plant parasite secretes a MIF protein prompted us to question the role of the cytokine in the plant-aphid interaction. We show here that expression of MIF genes is crucial for aphid survival, fecundity, and feeding on a host plant. The ectopic expression of aphid MIFs in leaf tissues inhibits major plant immune responses, such as the expression of defense-related genes, callose deposition, and hypersensitive cell death. Functional complementation analyses in vivo allowed demonstrating that MIF1 is the member of the MIF protein family that allows aphids to exploit their host plants. To our knowledge, this is the first report of a cytokine that is secreted by a parasite to modulate plant immune responses. Our findings suggest a so-far unsuspected conservation of infection strategies among parasites of animal and plant species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Plant immunity in plant–aphid interactions

    Science.gov (United States)

    Jaouannet, Maëlle; Rodriguez, Patricia A.; Lenoir, Camille J. G.; MacLeod, Ruari; Escudero-Martinez, Carmen; Bos, Jorunn I.B.

    2014-01-01

    Aphids are economically important pests that cause extensive feeding damage and transmit viruses. While some species have a broad host range and cause damage to a variety of crops, others are restricted to only closely related plant species. While probing and feeding aphids secrete saliva, containing effectors, into their hosts to manipulate host cell processes and promote infestation. Aphid effector discovery studies pointed out parallels between infection and infestation strategies of plant pathogens and aphids. Interestingly, resistance to some aphid species is known to involve plant resistance proteins with a typical NB-LRR domain structure. Whether these resistance proteins indeed recognize aphid effectors to trigger ETI remains to be elucidated. In addition, it was recently shown that unknown aphid derived elicitors can initiate reactive oxygen species (ROS) production and callose deposition and that these responses were dependent on BAK1 (BRASSINOSTERIOD INSENSITIVE 1-ASSOCIATED RECEPTOR KINASE 1) which is a key component of the plant immune system. In addition, BAK-1 contributes to non-host resistance to aphids pointing to another parallel between plant-pathogen and – aphid interactions. Understanding the role of plant immunity and non-host resistance to aphids is essential to generate durable and sustainable aphid control strategies. Although insect behavior plays a role in host selection and non-host resistance, an important observation is that aphids interact with non-host plants by probing the leaf surface, but are unable to feed or establish colonization. Therefore, we hypothesize that aphids interact with non-host plants at the molecular level, but are potentially not successful in suppressing plant defenses and/or releasing nutrients. PMID:25520727

  4. The Leucine-Rich Repeat Receptor-Like Kinase BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE1 and the Cytochrome P450 PHYTOALEXIN DEFICIENT3 Contribute to Innate Immunity to Aphids in Arabidopsis1[C][W][OPEN

    Science.gov (United States)

    Prince, David C.; Drurey, Claire; Zipfel, Cyril; Hogenhout, Saskia A.

    2014-01-01

    The importance of pathogen-associated molecular pattern-triggered immunity (PTI) against microbial pathogens has been recently demonstrated. However, it is currently unclear if this layer of immunity mediated by surface-localized pattern recognition receptors (PRRs) also plays a role in basal resistance to insects, such as aphids. Here, we show that PTI is an important component of plant innate immunity to insects. Extract of the green peach aphid (GPA; Myzus persicae) triggers responses characteristic of PTI in Arabidopsis (Arabidopsis thaliana). Two separate eliciting GPA-derived fractions trigger induced resistance to GPA that is dependent on the leucine-rich repeat receptor-like kinase BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE1 (BAK1)/SOMATIC-EMBRYOGENESIS RECEPTOR-LIKE KINASE3, which is a key regulator of several leucine-rich repeat-containing PRRs. BAK1 is required for GPA elicitor-mediated induction of reactive oxygen species and callose deposition. Arabidopsis bak1 mutant plants are also compromised in immunity to the pea aphid (Acyrthosiphon pisum), for which Arabidopsis is normally a nonhost. Aphid-derived elicitors induce expression of PHYTOALEXIN DEFICIENT3 (PAD3), a key cytochrome P450 involved in the biosynthesis of camalexin, which is a major Arabidopsis phytoalexin that is toxic to GPA. PAD3 is also required for induced resistance to GPA, independently of BAK1 and reactive oxygen species production. Our results reveal that plant innate immunity to insects may involve early perception of elicitors by cell surface-localized PRRs, leading to subsequent downstream immune signaling. PMID:24586042

  5. Derivative chromosome 1 and GLUT1 deficiency syndrome in a sibling pair

    Directory of Open Access Journals (Sweden)

    Akarsu Nurten

    2010-05-01

    Full Text Available Abstract Background Genomic imbalances constitute a major cause of congenital and developmental abnormalities. GLUT1 deficiency syndrome is caused by various de novo mutations in the facilitated human glucose transporter 1 gene (1p34.2 and patients with this syndrome have been diagnosed with hypoglycorrhachia, mental and developmental delay, microcephaly and seizures. Furthermore, 1q terminal deletions have been submitted in the recent reports and the absence of corpus callosum has been related to the deletion between C1orf100 and C1orf121 in 1q44. Results This study reports on a sibling pair with developmental delay, mental retardation, microcephaly, hypotonia, epilepsy, facial dysmorphism, ataxia and impaired speech. Chromosome analysis revealed a derivative chromosome 1 in both patients. FISH and MCB analysis showed two interstitial deletions at 1p34.2 and 1q44. SNP array and array-CGH analysis also determined the sizes of deletions detailed. The deleted region on 1p34.2 encompasses 33 genes, among which is GLUT1 gene (SLC2A1. However, the deleted region on 1q44 includes 59 genes and distal-proximal breakpoints were located in the ZNF672 gene and SMYD3 gene, respectively. Conclusion Haploinsufficiency of GLUT1 leads to GLUT1 deficiency syndrome, consistent with the phenotype in patients of this study. Conversely, in the deleted region on 1q44, none of the genes are related to findings in these patients. Additionally, the results confirm previous reports on that corpus callosal development may depend on the critical gene(s lying in 1q44 proximal to the SMYD3 gene.

  6. Volumetric Effects of Motor Cortex Injury on Recovery of Ipsilesional Dexterous Movements

    Science.gov (United States)

    Darling, Warren G.; Pizzimenti, Marc A.; Hynes, Stephanie M.; Rotella, Diane L.; Headley, Grant; Ge, Jizhi; Stilwell-Morecraft, Kimberly S.; McNeal, David W.; Solon-Cline, Kathryn M.; Morecraft, Robert J.

    2011-01-01

    Damage to the motor cortex of one hemisphere has classically been associated with contralateral upper limb paresis, but recent patient studies have identified deficits in both upper limbs. In non-human primates, we tested the hypothesis that the severity of ipsilesional upper limb motor impairment in the early post-injury phase depends on the volume of gray and white matter damage of the motor areas of the frontal lobe. We also postulated that substantial recovery would accompany minimal task practice and that ipsilesional limb recovery would be correlated with recovery of the contralesional limb. Gross (reaching) and fine hand motor functions were assessed for 3-12 months post-injury using two motor tests. Volumes of white and gray matter lesions were assessed using quantitative histology. Early changes in post-lesion motor performance were inversely correlated with white matter lesion volume indicating that larger lesions produced greater decreases in ipsilesional hand movement control. All monkeys showed improvements in ipsilesional hand motor skill during the post-lesion period, with reaching skill improvements being positively correlated with total lesion volume indicating larger lesions were associate with greater ipsilesional motor skill recovery. We suggest that reduced trans-callosal inhibition from the lesioned hemisphere may play a role in the observed skill improvements. Our findings show that significant ipsilesional hand motor recovery is likely to accompany injury limited to frontal motor areas. In humans, more pronounced ipsilesional motor deficits that invariably develop after stroke may, in part, be a consequence of more extensive subcortical white and gray matter damage. PMID:21703261

  7. A functional genomics approach identifies candidate effectors from the aphid species Myzus persicae (green peach aphid.

    Directory of Open Access Journals (Sweden)

    Jorunn I B Bos

    2010-11-01

    Full Text Available Aphids are amongst the most devastating sap-feeding insects of plants. Like most plant parasites, aphids require intimate associations with their host plants to gain access to nutrients. Aphid feeding induces responses such as clogging of phloem sieve elements and callose formation, which are suppressed by unknown molecules, probably proteins, in aphid saliva. Therefore, it is likely that aphids, like plant pathogens, deliver proteins (effectors inside their hosts to modulate host cell processes, suppress plant defenses, and promote infestation. We exploited publicly available aphid salivary gland expressed sequence tags (ESTs to apply a functional genomics approach for identification of candidate effectors from Myzus persicae (green peach aphid, based on common features of plant pathogen effectors. A total of 48 effector candidates were identified, cloned, and subjected to transient overexpression in Nicotiana benthamiana to assay for elicitation of a phenotype, suppression of the Pathogen-Associated Molecular Pattern (PAMP-mediated oxidative burst, and effects on aphid reproductive performance. We identified one candidate effector, Mp10, which specifically induced chlorosis and local cell death in N. benthamiana and conferred avirulence to recombinant Potato virus X (PVX expressing Mp10, PVX-Mp10, in N. tabacum, indicating that this protein may trigger plant defenses. The ubiquitin-ligase associated protein SGT1 was required for the Mp10-mediated chlorosis response in N. benthamiana. Mp10 also suppressed the oxidative burst induced by flg22, but not by chitin. Aphid fecundity assays revealed that in planta overexpression of Mp10 and Mp42 reduced aphid fecundity, whereas another effector candidate, MpC002, enhanced aphid fecundity. Thus, these results suggest that, although Mp10 suppresses flg22-triggered immunity, it triggers a defense response, resulting in an overall decrease in aphid performance in the fecundity assays. Overall, we

  8. Purification and characterization of AsES protein: a subtilisin secreted by Acremonium strictum is a novel plant defense elicitor.

    Science.gov (United States)

    Chalfoun, Nadia R; Grellet-Bournonville, Carlos F; Martínez-Zamora, Martín G; Díaz-Perales, Araceli; Castagnaro, Atilio P; Díaz-Ricci, Juan C

    2013-05-17

    In this work, the purification and characterization of an extracellular elicitor protein, designated AsES, produced by an avirulent isolate of the strawberry pathogen Acremonium strictum, are reported. The defense eliciting activity present in culture filtrates was recovered and purified by ultrafiltration (cutoff, 30 kDa), anionic exchange (Q-Sepharose, pH 7.5), and hydrophobic interaction (phenyl-Sepharose) chromatographies. Two-dimensional SDS-PAGE of the purified active fraction revealed a single spot of 34 kDa and pI 8.8. HPLC (C2/C18) and MS/MS analysis confirmed purification to homogeneity. Foliar spray with AsES provided a total systemic protection against anthracnose disease in strawberry, accompanied by the expression of defense-related genes (i.e. PR1 and Chi2-1). Accumulation of reactive oxygen species (e.g. H2O2 and O2(˙)) and callose was also observed in Arabidopsis. By using degenerate primers designed from the partial amino acid sequences and rapid amplification reactions of cDNA ends, the complete AsES-coding cDNA of 1167 nucleotides was obtained. The deduced amino acid sequence showed significant identity with fungal serine proteinases of the subtilisin family, indicating that AsES is synthesized as a larger precursor containing a 15-residue secretory signal peptide and a 90-residue peptidase inhibitor I9 domain in addition to the 283-residue mature protein. AsES exhibited proteolytic activity in vitro, and its resistance eliciting activity was eliminated when inhibited with PMSF, suggesting that its proteolytic activity is required to induce the defense response. This is, to our knowledge, the first report of a fungal subtilisin that shows eliciting activity in plants. This finding could contribute to develop disease biocontrol strategies in plants by activating its innate immunity.

  9. Purification and Characterization of AsES Protein

    Science.gov (United States)

    Chalfoun, Nadia R.; Grellet-Bournonville, Carlos F.; Martínez-Zamora, Martín G.; Díaz-Perales, Araceli; Castagnaro, Atilio P.; Díaz-Ricci, Juan C.

    2013-01-01

    In this work, the purification and characterization of an extracellular elicitor protein, designated AsES, produced by an avirulent isolate of the strawberry pathogen Acremonium strictum, are reported. The defense eliciting activity present in culture filtrates was recovered and purified by ultrafiltration (cutoff, 30 kDa), anionic exchange (Q-Sepharose, pH 7.5), and hydrophobic interaction (phenyl-Sepharose) chromatographies. Two-dimensional SDS-PAGE of the purified active fraction revealed a single spot of 34 kDa and pI 8.8. HPLC (C2/C18) and MS/MS analysis confirmed purification to homogeneity. Foliar spray with AsES provided a total systemic protection against anthracnose disease in strawberry, accompanied by the expression of defense-related genes (i.e. PR1 and Chi2-1). Accumulation of reactive oxygen species (e.g. H2O2 and O2˙̄) and callose was also observed in Arabidopsis. By using degenerate primers designed from the partial amino acid sequences and rapid amplification reactions of cDNA ends, the complete AsES-coding cDNA of 1167 nucleotides was obtained. The deduced amino acid sequence showed significant identity with fungal serine proteinases of the subtilisin family, indicating that AsES is synthesized as a larger precursor containing a 15-residue secretory signal peptide and a 90-residue peptidase inhibitor I9 domain in addition to the 283-residue mature protein. AsES exhibited proteolytic activity in vitro, and its resistance eliciting activity was eliminated when inhibited with PMSF, suggesting that its proteolytic activity is required to induce the defense response. This is, to our knowledge, the first report of a fungal subtilisin that shows eliciting activity in plants. This finding could contribute to develop disease biocontrol strategies in plants by activating its innate immunity. PMID:23530047

  10. Get Tough, Get Toxic, or Get a Bodyguard: Identifying Candidate Traits Conferring Belowground Resistance to Herbivores in Grasses.

    Science.gov (United States)

    Moore, Ben D; Johnson, Scott N

    2016-01-01

    Grasses (Poaceae) are the fifth-largest plant family by species and their uses for crops, forage, fiber, and fuel make them the most economically important. In grasslands, which broadly-defined cover 40% of the Earth's terrestrial surface outside of Greenland and Antarctica, 40-60% of net primary productivity and 70-98% of invertebrate biomass occurs belowground, providing extensive scope for interactions between roots and rhizosphere invertebrates. Grasses invest 50-70% of fixed carbon into root construction, which suggests roots are high value tissues that should be defended from herbivores, but we know relatively little about such defenses. In this article, we identify candidate grass root defenses, including physical (tough) and chemical (toxic) resistance traits, together with indirect defenses involving recruitment of root herbivores' natural enemies. We draw on relevant literature to establish whether these defenses are present in grasses, and specifically in grass roots, and which herbivores of grasses are affected by these defenses. Physical defenses could include structural macro-molecules such as lignin, cellulose, suberin, and callose in addition to silica and calcium oxalate. Root hairs and rhizosheaths, a structural adaptation unique to grasses, might also play defensive roles. To date, only lignin and silica have been shown to negatively affect root herbivores. In terms of chemical resistance traits, nitrate, oxalic acid, terpenoids, alkaloids, amino acids, cyanogenic glycosides, benzoxazinoids, phenolics, and proteinase inhibitors have the potential to negatively affect grass root herbivores. Several good examples demonstrate the existence of indirect defenses in grass roots, including maize, which can recruit entomopathogenic nematodes (EPNs) via emission of (E)-β-caryophyllene, and similar defenses are likely to be common. In producing this review, we aimed to equip researchers with candidate root defenses for further research.

  11. First Direct Evidence for Natal Wintering Ground Fidelity and Estimate of Juvenile Survival in the New Zealand Southern Right Whale Eubalaena australis.

    Science.gov (United States)

    Carroll, E L; Fewster, R M; Childerhouse, S J; Patenaude, N J; Boren, L; Baker, C S

    2016-01-01

    Juvenile survival and recruitment can be more sensitive to environmental, ecological and anthropogenic factors than adult survival, influencing population-level processes like recruitment and growth rate in long-lived, iteroparous species such as southern right whales. Conventionally, Southern right whales are individually identified using callosity patterns, which do not stabilise until 6-12 months, by which time the whale has left its natal wintering grounds. Here we use DNA profiling of skin biopsy samples to identify individual Southern right whales from year of birth and document their return to the species' primary wintering ground in New Zealand waters, the Subantarctic Auckland Islands. We find evidence of natal fidelity to the New Zealand wintering ground by the recapture of 15 of 57 whales, first sampled in year of birth and available for subsequent recapture, during winter surveys to the Auckland Islands in 1995-1998 and 2006-2009. Four individuals were recaptured at the ages of 9 to 11, including two females first sampled as calves in 1998 and subsequently resampled as cows with calves in 2007. Using these capture-recapture records of known-age individuals, we estimate changes in survival with age using Cormack-Jolly-Seber models. Survival is modelled using discrete age classes and as a continuous function of age. Using a bootstrap method to account for uncertainty in model selection and fitting, we provide the first direct estimate of juvenile survival for this population. Our analyses indicate a high annual apparent survival for juveniles at between 0.87 (standard error (SE) 0.17, to age 1) and 0.95 (SE 0.05: ages 2-8). Individual identification by DNA profiling is an effective method for long-term demographic and genetic monitoring, particularly in animals that change identifiable features as they develop or experience tag loss over time.

  12. Diagnosis of neuromyelitis optica (NMO) spectrum disorders: is MRI obsolete?

    Energy Technology Data Exchange (ETDEWEB)

    Downer, Jonathan James; Carter, Ranjana; Kueker, Wilhelm; Quaghebeur, Gerardine [John Radcliffe Hospital, Department of Neuroradiology, Oxford (United Kingdom); Leite, Maria Isabel; Palace, Jacqueline [Oxford University, Department of Clinical Neurology, Oxford (United Kingdom)

    2012-04-15

    Neuromyelitis optica (NMO) is a severe demyelinating disease that preferentially involves spinal cord and optic nerve. It is part of a spectrum of neurological conditions associated with antibodies to aquaporin-4 (AQP4). This study investigates the role of MRI where novel, more sensitive AQP4 antibody immunoassay techniques are being used. Retrospective review of neuroimaging in 69 patients (25 antibody positive, 44 antibody negative), investigated in the context of suspected NMO or NMO spectrum disorder, was performed independently by two consultant neuroradiologists. Longitudinally extensive, central spinal cord lesions were more frequent in AQP4 positive patients (95.2% vs 35.5%, p < 0.0001; 85.7% vs 45.2%, p = 0.015). Multiple sclerosis diagnostic criteria were less frequently fulfilled on brain MRI in antibody positive patients (5.6% vs 33.3%, p = 0.035). Juxtacortical and corpus callosal lesions were also less common in this group (16.7% vs 46.7%, p = 0.063; 5.6% vs 46.7%, p = 0.0034). Hypothalamic and periependymal disease related to the aqueduct was not seen in antibody negative patients. T1 hypointensity was more common in cord lesions of antibody positive patients (75.0% vs 35.3%, p = 0.037). However, this characteristic did not discriminate antibody positive and negative longitudinally extensive cord lesions (73.3% vs 62.5%, p = 0.66). The NMO spectrum of diseases are among an increasing number of neurological conditions defined by serological tests. However, despite improved immunoassay techniques, MRI of the brain and spinal cord continues to be among the first-line investigations in these patients, providing valuable diagnostic information that will help guide patient management. (orig.)

  13. Chromium-Induced Ultrastructural Changes and Oxidative Stress in Roots of Arabidopsis thaliana

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    Eleftherios P. Eleftheriou

    2015-07-01

    Full Text Available Chromium (Cr is an abundant heavy metal in nature, toxic to living organisms. As it is widely used in industry and leather tanning, it may accumulate locally at high concentrations, raising concerns for human health hazards. Though Cr effects have extensively been investigated in animals and mammals, in plants they are poorly understood. The present study was then undertaken to determine the ultrastructural malformations induced by hexavalent chromium [Cr(VI], the most toxic form provided as 100 μM potassium dichromate (K2Cr2O7, in the root tip cells of the model plant Arabidopsis thaliana. A concentration-dependent decrease of root growth and a time-dependent increase of dead cells, callose deposition, hydrogen peroxide (H2O2 production and peroxidase activity were found in Cr(VI-treated seedlings, mostly at the transition root zone. In the same zone, nuclei remained ultrastructurally unaffected, but in the meristematic zone some nuclei displayed bulbous outgrowths or contained tubular structures. Endoplasmic reticulum (ER was less affected under Cr(VI stress, but Golgi bodies appeared severely disintegrated. Moreover, mitochondria and plastids became spherical and displayed translucent stroma with diminished internal membranes, but noteworthy is that their double-membrane envelopes remained structurally intact. Starch grains and electron dense deposits occurred in the plastids. Amorphous material was also deposited in the cell walls, the middle lamella and the vacuoles. Some vacuoles were collapsed, but the tonoplast appeared integral. The plasma membrane was structurally unaffected and the cytoplasm contained opaque lipid droplets and dense electron deposits. All electron dense deposits presumably consisted of Cr that is sequestered from sensitive sites, thus contributing to metal tolerance. It is concluded that the ultrastructural changes are reactive oxygen species (ROS-correlated and the malformations observed are organelle specific.

  14. Multimodal structural MRI in the diagnosis of motor neuron diseases

    Directory of Open Access Journals (Sweden)

    Pilar M. Ferraro

    2017-01-01

    Full Text Available This prospective study developed an MRI-based method for identification of individual motor neuron disease (MND patients and test its accuracy at the individual patient level in an independent sample compared with mimic disorders. 123 patients with amyotrophic lateral sclerosis (ALS, 44 patients with predominantly upper motor neuron disease (PUMN, 20 patients with ALS-mimic disorders, and 78 healthy controls were studied. The diagnostic accuracy of precentral cortical thickness and diffusion tensor (DT MRI metrics of corticospinal and motor callosal tracts were assessed in a training cohort and externally proved in a validation cohort using a random forest analysis. In the training set, precentral cortical thickness showed 0.86 and 0.89 accuracy in differentiating ALS and PUMN patients from controls, while DT MRI distinguished the two groups from controls with 0.78 and 0.92 accuracy. In ALS vs controls, the combination of cortical thickness and DT MRI metrics (combined model improved the classification pattern (0.91 accuracy. In the validation cohort, the best accuracy was reached by DT MRI (0.87 and 0.95 accuracy in ALS and PUMN vs mimic disorders. The combined model distinguished ALS and PUMN patients from mimic syndromes with 0.87 and 0.94 accuracy. A multimodal MRI approach that incorporates motor cortical and white matter alterations yields statistically significant improvement in accuracy over using each modality separately in the individual MND patient classification. DT MRI represents the most powerful tool to distinguish MND from mimic disorders.

  15. Sex differences in white matter integrity in youths with attention-deficit/hyperactivity disorder: a pilot study.

    Science.gov (United States)

    King, Jace B; Yurgelun-Todd, Deborah; Stoeckel, Amanda; DiMuzio, Jennifer M; Lopez-Larson, Melissa P

    2015-01-01

    Widespread disparities in white matter (WM) microstructure and organization have been found in adolescents with attention-deficit/hyperactivity disorder (ADHD); however, little is known about the role sex plays in these differences. The present diffusion tensor imaging (DTI) study performed whole-brain, tract-based, voxel-wise, and region of interest (ROI) analyses to investigate WM microstructure differences between ADHD and healthy control (HC) adolescents to examine the impact of sex on measures of fractional anisotropy (FA). Eighteen adolescents with ADHD and 24 HC were included in this study. All participants received a 64-direction DTI scan on a 3 Tesla Siemens scanner. FSL's TBSS was used to perform whole-brain, tract-based, voxel-wise analyses. Tracts demonstrating significant sex-by-diagnosis interactions were further evaluated using univariate analyses performed on mean FA data that were extracted from ROIs using the Johns Hopkins University WM tractography atlas. TBSS analyses between diagnostic groups revealed significantly increased FA in HC relative to ADHD in the bilateral superior longitudinal fasciculus (SLF), forceps major, left cingulum, and bilateral callosal regions. In addition, both TBSS and separate ROI analyses revealed significant sex-by-diagnosis interactions for the corticospinal tract (CST), inferior longitudinal fasciculus (ILF) and SLF. In the HC group, FA was increased in males relative to females for all analyses. In WM regions demonstrating a significant sex-by-diagnosis, FA was increased in females relative to males in the ADHD group. Our findings suggest that WM microstructure in several major WM tracts differs between males and females with ADHD. These differences in WM microstructure may account for some of the differences in ADHD subtypes and comorbidities seen between the sexes. Additional studies in ADHD, examining sex differences in phenotypic expression, treatment response and brain network trajectories are warranted.

  16. Development of human white matter fiber pathways: From newborn to adult ages.

    Science.gov (United States)

    Cohen, Andrew H; Wang, Rongpin; Wilkinson, Molly; MacDonald, Patrick; Lim, Ashley R; Takahashi, Emi

    2016-05-01

    Major long-range white matter pathways (cingulum, fornix, uncinate fasciculus [UF], inferior fronto-occipital fasciculus [IFOF], inferior longitudinal fasciculus [ILF], thalamocortical [TC], and corpus callosal [CC] pathways) were identified in eighty-three healthy humans ranging from newborn to adult ages. We tracked developmental changes using high-angular resolution diffusion MR tractography. Fractional anisotropy (FA), apparent diffusion coefficient, number, length, and volume were measured in pathways in each subject. Newborns had fewer, and more sparse, pathways than those of the older subjects. FA, number, length, and volume of pathways gradually increased with age and reached a plateau between 3 and 5 years of age. Data were further analyzed by normalizing with mean adult values as well as with each subject's whole brain values. Comparing subjects of 3 years old and under to those over 3 years old, the studied pathways showed differential growth patterns. The CC, bilateral cingulum, bilateral TC, and the left IFOF pathways showed significant growth both in volume and length, while the bilateral fornix, bilateral ILF and bilateral UF showed significant growth only in volume. The TC and CC took similar growth patterns with the whole brain. FA values of the cingulum and IFOF, and the length of ILF showed leftward asymmetry. The fornix, ILF and UF occupied decreased space compared to the whole brain during development with higher FA values, likely corresponding to extensive maturation of the pathways compared to the mean whole brain maturation. We believe that the outcome of this study will provide an important database for future reference. Copyright © 2016 ISDN. Published by Elsevier Ltd. All rights reserved.

  17. Both projection and commissural pathways are disrupted in individuals with chronic stroke: investigating microstructural white matter correlates of motor recovery.

    Science.gov (United States)

    Borich, Michael R; Mang, Cameron; Boyd, Lara A

    2012-08-29

    Complete recovery of motor function after stroke is rare with deficits persisting into the chronic phase of recovery. Diffusion tensor imaging (DTI) can evaluate relationships between white matter microstructure and motor function after stroke. The objective of this investigation was to characterize microstructural fiber integrity of motor and sensory regions of the corpus callosum (CC) and descending motor outputs of the posterior limb of the internal capsule (PLIC) in individuals with chronic stroke and evaluate the relationships between white matter integrity and motor function. Standardized measures of upper extremity motor function were measured in thirteen individuals with chronic stroke. Manual dexterity was assessed in thirteen healthy age-matched control participants. DTI scans were completed for each participant. Fractional anisotropy (FA) of a cross-section of sensory and motor regions of the CC and the PLIC bilaterally were quantified. Multivariate analysis of variance evaluated differences between stroke and healthy groups. Correlational analyses were conducted for measures of motor function and FA. The stroke group exhibited reduced FA in the sensory (p = 0.001) region of the CC, contra- (p = 0.032) and ipsilesional (p = 0.001) PLIC, but not the motor region of the CC (p = 0.236). In the stroke group, significant correlations between contralesional PLIC FA and level of physical impairment (p = 0.005), grip strength (p = 0.006) and hand dexterity (p = 0.036) were observed. Microstructural status of the sensory region of the CC is reduced in chronic stroke. Future work is needed to explore relationships between callosal sensorimotor fiber integrity and interhemispheric interactions post-stroke. In addition, contralesional primary motor output tract integrity is uniquely and closely associated with multiple dimensions of motor recovery in the chronic phase of stroke suggesting it may be an important biomarker of overall motor recovery.

  18. Motor recovery and microstructural change in rubro-spinal tract in subcortical stroke.

    Science.gov (United States)

    Takenobu, Yohei; Hayashi, Takuya; Moriwaki, Hiroshi; Nagatsuka, Kazuyuki; Naritomi, Hiroaki; Fukuyama, Hidenao

    2014-01-01

    The mechanism of motor recovery after stroke may involve reorganization of the surviving networks. However, details of adaptive changes in structural connectivity are not well understood. Here, we show long-term changes in white matter microstructure that relate to motor recovery in stroke patients. We studied ten subcortical ischemic stroke patients who showed motor hemiparesis at the initial clinical examination and an infarcted lesion centered in the posterior limb of internal capsule of the unilateral hemisphere at the initial diffusion-weighted magnetic resonance imaging scan. The participants underwent serial diffusion tensor imaging and motor function assessments at three consecutive time points; within 2 weeks, and at 1 and 3 months after the onset. Fractional anisotropy (FA) was analyzed for regional differences between hemispheres and time points, as well as for correlation with motor recovery using a tract-based spatial statistics analysis. The results showed significantly increased FA in the red nucleus and dorsal pons in the ipsi-lesional side at 3 months, and significantly decreased FA in the ipsi-lesional internal capsule at all time points, and in the cerebral peduncle, corona radiata, and corpus callosum at 3 months. In the correlation analysis, FA values of clusters in the red nucleus, dorsal pons, midbody of corpus callosum, and cingulum were positively correlated with recovery of motor function. Our study suggests that changes in white matter microstructure in alternative descending motor tracts including the rubro-spinal pathway, and interhemispheric callosal connections may play a key role in compensating for motor impairment after subcortical stroke.

  19. New insights in the homotopic and heterotopic connectivity of the frontal portion of the human corpus callosum revealed by microdissection and diffusion tractography.

    Science.gov (United States)

    De Benedictis, Alessandro; Petit, Laurent; Descoteaux, Maxime; Marras, Carlo Efisio; Barbareschi, Mattia; Corsini, Francesco; Dallabona, Monica; Chioffi, Franco; Sarubbo, Silvio

    2016-12-01

    Extensive studies revealed that the human corpus callosum (CC) plays a crucial role in providing large-scale bi-hemispheric integration of sensory, motor and cognitive processing, especially within the frontal lobe. However, the literature lacks of conclusive data regarding the structural macroscopic connectivity of the frontal CC. In this study, a novel microdissection approach was adopted, to expose the frontal fibers of CC from the dorsum to the lateral cortex in eight hemispheres and in one entire brain. Post-mortem results were then combined with data from advanced constrained spherical deconvolution in 130 healthy subjects. We demonstrated as the frontal CC provides dense inter-hemispheric connections. In particular, we found three types of fronto-callosal fibers, having a dorso-ventral organization. First, the dorso-medial CC fibers subserve homotopic connections between the homologous medial cortices of the superior frontal gyrus. Second, the ventro-lateral CC fibers subserve homotopic connections between lateral frontal cortices, including both the middle frontal gyrus and the inferior frontal gyrus, as well as heterotopic connections between the medial and lateral frontal cortices. Third, the ventro-striatal CC fibers connect the medial and lateral frontal cortices with the contralateral putamen and caudate nucleus. We also highlighted an intricate crossing of CC fibers with the main association pathways terminating in the lateral regions of the frontal lobes. This combined approach of ex vivo microdissection and in vivo diffusion tractography allowed demonstrating a previously unappreciated three-dimensional architecture of the anterior frontal CC, thus clarifying the functional role of the CC in mediating the inter-hemispheric connectivity. Hum Brain Mapp 37:4718-4735, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  20. Increased number of astrocytes and macrophages/microglial cells in the corpus callosum in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Sugiyama, Mikiko; Takao, Masaki; Hatsuta, Hiroyuki; Funabe, Sayaka; Ito, Shinji; Obi, Tomokazu; Tanaka, Fumiaki; Kuroiwa, Yoshiyuki; Murayama, Shigeo

    2013-12-01

    Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by degeneration of both upper and lower motor neurons. Neuropathologically, degeneration of the corticospinal tracts is evident and may be associated with loss of motor neurons in the motor cortex. The data from a recently developed imaging technology, the diffusion tensor imaging method of MRI have suggested that white matter in the corpus callosum (CC) is lost in patients with ALS. However, the specific neuropathologic changes of the commissural fibers remain unclear. To investigate the pathologic changes of the CC in ALS, we analyzed midsagittal sections of the CC from eight individuals with ALS and eight controls by using conventional staining and immunohistochemistry with antibodies against CD68, GFAP and phosphorylated neurofilament (SMI-31). The CC was divided into seven areas. The number of CD68-immunoreactive macrophages/microglia and GFAP-immunoreactive astrocytes was significantly higher in individuals with ALS than in controls in all areas of the CC except the rostrum. Among the patients with ALS, the number of macrophages/microglia and astrocytes was significantly higher in the posterior midbody and isthmus than in the rostrum. There was no significant difference in number of SMI-31 immunoreactive axons between ALS and control group as well as among each area of the CC. These findings suggest that pathologic changes in the CC in ALS are present in the posterior midbody and isthmus, where callosal motor fibers may traverse between the two hemispheres. CD68 and GFAP immunohistochemistry are sensitive methods to detect those pathologic changes in routine paraffin-embedded specimens. © 2013 Japanese Society of Neuropathology.

  1. Corpus callosum damage predicts disability progression and cognitive dysfunction in primary-progressive MS after five years.

    Science.gov (United States)

    Bodini, Benedetta; Cercignani, Mara; Khaleeli, Zhaleh; Miller, David H; Ron, Maria; Penny, Sophie; Thompson, Alan J; Ciccarelli, Olga

    2013-05-01

    We aim to identify specific areas of white matter (WM) and grey matter (GM), which predict disability progression and cognitive dysfunction after five years in patients with primary-progressive multiple sclerosis (PPMS). Thirty-two patients with early PPMS were assessed at baseline and after five years on the Expanded Disability Status Scale (EDSS), and EDSS step-changes were calculated. At year five, a subgroup of 25 patients and 31 healthy controls underwent a neuropsychological assessment. Baseline imaging consisted of dual-echo (proton density and T2-weighted), T1-weighted volumetric, and diffusion tensor imaging. Fractional anisotropy (FA) maps were created, and fed into tract-based spatial statistics. To compensate for the potential bias introduced by WM lesions, the T1 volumes underwent a lesion-filling procedure before entering a voxel-based morphometry protocol. To investigate whether FA and GM volume predicted EDSS step-changes over five years and neuropsychological tests scores at five years, voxelwise linear regression analyses were performed. Lower FA in the splenium of the corpus callosum (CC) predicted a greater progression of disability over the follow-up. Lower FA along the entire CC predicted worse verbal memory, attention and speed of information processing, and executive function at five years. GM baseline volume did not predict any clinical variable. Our findings highlight the importance of damage to the interhemispheric callosal pathways in determining physical and cognitive disability in PPMS. Disruption of these pathways, which interconnect motor and cognitive networks between the two hemispheres, may result in a disconnection syndrome that contributes to long-term physical and cognitive disability. Copyright © 2011 Wiley Periodicals, Inc.

  2. Genetic and cellular analysis of cross-incompatibility in Zea mays.

    Science.gov (United States)

    Lu, Yongxian; Kermicle, Jerry L; Evans, Matthew M S

    2014-03-01

    Three genetic systems conferring cross-incompatibility have been described in Zea mays: Teosinte crossing barrier1-strong (Tcb1-s) found in teosinte, and Gametophyte factor1-strong (Ga1-s) and Ga2-s found in maize and teosinte. The reproductive barrier between maize and some weedy teosintes is controlled by the Tcb1-s locus. Multi-generation inheritance experiments on two independent Tcb1-s lineages show that the Tcb1-s barrier is unstable in some maize lines. Reciprocal crosses between Tcb1-s tester plants and three recombinants in the Tcb1-s mapping region demonstrate that the Tcb1-s haplotype contains separable male and female components. In vivo assays of the dynamics of pollen tube growth and pollen tube morphology during rejection of incompatible pollen in silks carrying the Tcb1-s, Ga1-s, or Ga2-s barriers showed that, in all three, pollen tube growth is slower than in compatible crosses at early stages and had ceased by 24 h after pollination. In all three crossing barrier systems, incompatible pollen tubes have clustered callose plugs in contrast to pollen tubes of compatible crosses. Incompatible pollen tubes growing in the Tcb1-s, Ga1-s, and Ga2-s silks have different morphologies: straight, curved, and kinked, respectively. The distinct morphologies suggest that these crossing barriers block incompatible pollen through different mechanisms. This study lays the foundation for cloning the Tcb1 genes and provides clues about the cellular mechanisms involved in pollen rejection in the Tcb1-s, Ga1-s, and Ga2-s crossing barriers.

  3. Neuroimaging evidence of major morpho-anatomical and functional abnormalities in the BTBR T+TF/J mouse model of autism.

    Directory of Open Access Journals (Sweden)

    Luca Dodero

    Full Text Available BTBR T+tf/J (BTBR mice display prominent behavioural deficits analogous to the defining symptoms of autism, a feature that has prompted a widespread use of the model in preclinical autism research. Because neuro-behavioural traits are described with respect to reference populations, multiple investigators have examined and described the behaviour of BTBR mice against that exhibited by C57BL/6J (B6, a mouse line characterised by high sociability and low self-grooming. In an attempt to probe the translational relevance of this comparison for autism research, we used Magnetic Resonance Imaging (MRI to map in both strain multiple morpho-anatomical and functional neuroimaging readouts that have been extensively used in patient populations. Diffusion tensor tractography confirmed previous reports of callosal agenesis and lack of hippocampal commissure in BTBR mice, and revealed a concomitant rostro-caudal reorganisation of major cortical white matter bundles. Intact inter-hemispheric tracts were found in the anterior commissure, ventro-medial thalamus, and in a strain-specific white matter formation located above the third ventricle. BTBR also exhibited decreased fronto-cortical, occipital and thalamic gray matter volume and widespread reductions in cortical thickness with respect to control B6 mice. Foci of increased gray matter volume and thickness were observed in the medial prefrontal and insular cortex. Mapping of resting-state brain activity using cerebral blood volume weighted fMRI revealed reduced cortico-thalamic function together with foci of increased activity in the hypothalamus and dorsal hippocampus of BTBR mice. Collectively, our results show pronounced functional and structural abnormalities in the brain of BTBR mice with respect to control B6 mice. The large and widespread white and gray matter abnormalities observed do not appear to be representative of the neuroanatomical alterations typically observed in autistic patients. The

  4. [A case of cerebral infarction presenting as retrosplenial amnesia].

    Science.gov (United States)

    Katai, S; Maruyama, T; Hashimoto, T; Yanagisawa, N

    1992-11-01

    We report a 73-year-old right-handed female who presented with an acute amnesic syndrome. On November 18, 1991, she was admitted to a local hospital complaining of sudden-onset vertigo and nausea, but immediately after the admission she developed an amnesic syndrome. On November 27, she was transferred to our hospital for further assessment of her memory disturbance. Neurologically she was normal except for mild right hemianopsia and increased deep tendon reflexes in the extremities. Neuropsychological assessments were performed over 3 weeks. She was always alert, attentive, and cooperative. She had no confabulation. On the Wechsler Adult Intelligence Scale revised (WAIS-R), her total IQ was 110. Frontal, verbal, and perceptual functions and motor performance were normal. She had no signs of a callosal disconnection. Despite these preserved functions, her memory function was obviously disturbed. Several memory betteries showed that her recent memory for both verbal and visual modalities was impaired, while her immediate memory such as digit span was preserved. For remote memory her retrograde episodic memory concerning both personal and public events was almost intact, although she had a profound anterograde amnesia. In particular she recalled her personal information about just-premorbid events in detail. On the other hand, her semantic memory, for example understanding of proverbs, geography, and scientific law, was preserved. Taken together, her procedural memory on learning tasks, such as "Tower of Hanoi" and mirror drawing, was intact. Computed tomography demonstrated a low-density area medial to the trigon of the left ventricle.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Impaired volitional closure of the left eyelid after right anterior cerebral artery infarction: apraxia due to interhemispheric disconnection?

    Science.gov (United States)

    Korn, Thomas; Reith, Wolfgang; Becker, Georg

    2004-02-01

    The inability of volitional unilateral eyelid closure is an uncommon symptom of a central nervous system disorder. When it occurs as the result of a localized brain lesion, it is debated to be a form of supranuclear facial palsy or an apraxic phenomenon. To report and discuss a unilateral (left-sided) higher-order movement disorder of the facial periocular musculature bearing apraxic features. University neurology department. A 78-year-old right-handed man was admitted to the hospital with a left-sided brachiofacial hemiparesis of sudden onset. After thrombolysis with intravenous recombinant tissue-type plasminogen activator, the hemiparesis, including the left-sided facial weakness, disappeared. Serial computed tomographic scans showed that the patient was left with a stroke in the right anterior cerebral artery territory, affecting the frontal commissural fibers of the corpus callosum. There were no signs of upper motor neuron facial paresis on the left side when gesturing in a natural context. Eyelid closure was complete during sleep. However, left eyelid closure and elevation of the left eyebrow were not possible on verbal command. In contrast, voluntary innervation of the perioral facial musculature was performed properly. The voluntary-automatic dissociation of our patient's eyelid closure was suggestive of an apraxic disorder. Disconnection from a praxis center caused by callosal damage may be assumed to be the underlying cause. The unilaterality of the symptom might imply that in a bilaterally organized corticonuclear system such as upper face innervation, it is the crossing fibers that are primarily involved in praxis tasks.

  6. Involvement of metabolic components, volatile compounds, PR proteins, and mechanical strengthening in multilayer protection of cucumber plants against Rhizoctonia solani activated by Trichoderma atroviride TRS25.

    Science.gov (United States)

    Nawrocka, Justyna; Małolepsza, U; Szymczak, K; Szczech, M

    2017-09-06

    In the present study, the spread of Rhizoctonia solani-induced disease was limited when cucumber plants were pretreated with Trichoderma atroviride TRS25. The systemic disease suppression was related to TRS25-induced resistance (TISR) induction with simultaneous plant growth promotion. Protection of cucumber was related to enhanced activity of defense enzymes, e.g., guaiacol peroxidase (GPX), syringaldazine peroxidase (SPX), phenylalanine ammonia lyase (PAL), and polyphenol oxidase (PPO) as well as phenolic (PC) concentration increases in the conditions of hydrogen peroxide (H2O2) accumulation, resulting in thiobarbituric acid reactive substance (TBARS) decrease. Moreover, the obtained results indicated that TISR might depend on accumulation of salicylic acid derivatives, that is methyl salicylate (MeSA), ethylhexyl salicylate (EHS), salicylic acid glucosylated conjugates (SAGC), and β-cyclocitral as well as volatile organic compounds (VOC) such as Z-3-hexanal, Z-3-hexenol, and E-2-hexenal. The results point to important, not previously documented, roles of these VOC in TISR signaling with up-regulation of PR1 and PR5 gene characteristic of systemic acquired resistance (SAR) and of PR4 gene, marker of induced systemic resistance (ISR). The study established that TRS25 enhanced deposition of callose and lignin in specialized plant cells, which protected vascular system in cucumber shoots and roots as well as assimilation cells and dermal tissues in shoots and leaves. These compounds protected cucumber organs against R. solani influence and made them more flexible and resilient, which contributed to better nutrition and hydration of plants. The growth promotion coupled with systemic mobilization of biochemical and mechanical strengthening might be involved in multilayer protection of cucumber against R. solani activated by TRS25.

  7. Cell death control: the interplay of apoptosis and autophagy in the pathogenicity of Sclerotinia sclerotiorum.

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    Mehdi Kabbage

    Full Text Available Programmed cell death is characterized by a cascade of tightly controlled events that culminate in the orchestrated death of the cell. In multicellular organisms autophagy and apoptosis are recognized as two principal means by which these genetically determined cell deaths occur. During plant-microbe interactions cell death programs can mediate both resistant and susceptible events. Via oxalic acid (OA, the necrotrophic phytopathogen Sclerotinia sclerotiorum hijacks host pathways and induces cell death in host plant tissue resulting in hallmark apoptotic features in a time and dose dependent manner. OA-deficient mutants are non-pathogenic and trigger a restricted cell death phenotype in the host that unexpectedly exhibits markers associated with the plant hypersensitive response including callose deposition and a pronounced oxidative burst, suggesting the plant can recognize and in this case respond, defensively. The details of this plant directed restrictive cell death associated with OA deficient mutants is the focus of this work. Using a combination of electron and fluorescence microscopy, chemical effectors and reverse genetics, we show that this restricted cell death is autophagic. Inhibition of autophagy rescued the non-pathogenic mutant phenotype. These findings indicate that autophagy is a defense response in this necrotrophic fungus/plant interaction and suggest a novel function associated with OA; namely, the suppression of autophagy. These data suggest that not all cell deaths are equivalent, and though programmed cell death occurs in both situations, the outcome is predicated on who is in control of the cell death machinery. Based on our data, we suggest that it is not cell death per se that dictates the outcome of certain plant-microbe interactions, but the manner by which cell death occurs that is crucial.

  8. A behavioral evaluation of sex differences in a mouse model of severe neuronal migration disorder.

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    Dongnhu T Truong

    Full Text Available Disruption of neuronal migration in humans is associated with a wide range of behavioral and cognitive outcomes including severe intellectual disability, language impairment, and social dysfunction. Furthermore, malformations of cortical development have been observed in a number of neurodevelopmental disorders (e.g. autism and dyslexia, where boys are much more commonly diagnosed than girls (estimates around 4 to 1. The use of rodent models provides an excellent means to examine how sex may modulate behavioral outcomes in the presence of comparable abnormal neuroanatomical presentations. Initially characterized by Rosen et al. 2012, the BXD29- Tlr4(lps-2J /J mouse mutant exhibits a highly penetrant neuroanatomical phenotype that consists of bilateral midline subcortical nodular heterotopia with partial callosal agenesis. In the current study, we confirm our initial findings of a severe impairment in rapid auditory processing in affected male mice. We also report that BXD29- Tlr4(lps-2J /J (mutant female mice show no sparing of rapid auditory processing, and in fact show deficits similar to mutant males. Interestingly, female BXD29- Tlr4(lps-2J /J mice do display superiority in Morris water maze performance as compared to wild type females, an affect not seen in mutant males. Finally, we report new evidence that BXD29- Tlr4(lps-2J /J mice, in general, show evidence of hyper-social behaviors. In closing, the use of the BXD29- Tlr4(lps-2J /J strain of mice - with its strong behavioral and neuroanatomical phenotype - may be highly useful in characterizing sex independent versus dependent mechanisms that interact with neural reorganization, as well as clinically relevant abnormal behavior resulting from aberrant neuronal migration.

  9. Homologous RXLR effectors from Hyaloperonospora arabidopsidis and Phytophthora sojae suppress immunity in distantly related plants.

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    Anderson, Ryan G; Casady, Megan S; Fee, Rachel A; Vaughan, Martha M; Deb, Devdutta; Fedkenheuer, Kevin; Huffaker, Alisa; Schmelz, Eric A; Tyler, Brett M; McDowell, John M

    2012-12-01

    Diverse pathogens secrete effector proteins into plant cells to manipulate host cellular processes. Oomycete pathogens contain large complements of predicted effector genes defined by an RXLR host cell entry motif. The genome of Hyaloperonospora arabidopsidis (Hpa, downy mildew of Arabidopsis) contains at least 134 candidate RXLR effector genes. Only a small subset of these genes is conserved in related oomycetes from the Phytophthora genus. Here, we describe a comparative functional characterization of the Hpa RXLR effector gene HaRxL96 and a homologous gene, PsAvh163, from the Glycine max (soybean) pathogen Phytophthora sojae. HaRxL96 and PsAvh163 are induced during the early stages of infection and carry a functional RXLR motif that is sufficient for protein uptake into plant cells. Both effectors can suppress immune responses in soybean. HaRxL96 suppresses immunity in Nicotiana benthamiana, whereas PsAvh163 induces an HR-like cell death response in Nicotiana that is dependent on RAR1 and Hsp90.1. Transgenic Arabidopsis plants expressing HaRxL96 or PsAvh163 exhibit elevated susceptibility to virulent and avirulent Hpa, as well as decreased callose deposition in response to non-pathogenic Pseudomonas syringae. Both effectors interfere with defense marker gene induction, but do not affect salicylic acid biosynthesis. Together, these experiments demonstrate that evolutionarily conserved effectors from different oomycete species can suppress immunity in plant species that are divergent from the source pathogen's host. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.

  10. Transcriptional regulation of male-sterility in 7B-1 male-sterile tomato mutant.

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    Vahid Omidvar

    Full Text Available The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. To underline the molecular mechanism regulating the male-sterility in 7B-1, transcriptomic profiles of the 7B-1 male-sterile and wild type (WT anthers were studied using mRNA sequencing (RNA-Seq. In total, 768 differentially expressed genes (DEGs were identified, including 132 up-regulated and 636 down-regulated transcripts. Gene ontology (GO enrichment analysis of DEGs suggested a general impact of the 7B-1 mutation on metabolic processes, such as proteolysis and carbohydrate catabolic process. Sixteen candidates with key roles in regulation of anther development were subjected to further analysis using qRT-PCR and in situ hybridization. Cytological studies showed several defects associated with anther development in the 7B-1 mutant, including unsynchronized anther maturation, dysfunctional meiosis, arrested microspores, defect in callose degradation and abnormal tapetum development. TUNEL assay showed a defect in programmed cell death (PCD of tapetal cells in 7B-1 anthers. The present study provides insights into the transcriptome of the 7B-1 mutant. We identified several genes with altered expression level in 7B-1 (including beta-1,3 glucanase, GA2oxs, cystatin, cysteine protease, pectinesterase, TA29, and actin that could potentially regulate anther developmental processes, such as meiosis, tapetum development, and cell-wall formation/degradation.

  11. Comprehensive analysis of genic male sterility-related genes in Brassica rapa using a newly developed Br300K oligomeric chip.

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    Xiangshu Dong

    Full Text Available To identify genes associated with genic male sterility (GMS that could be useful for hybrid breeding in Chinese cabbage (Brassicarapa ssp. pekinensis, floral bud transcriptome analysis was carried out using a B. rapa microarray with 300,000 probes (Br300K. Among 47,548 clones deposited on a Br300K microarray with seven probes of 60 nt length within the 3' 150 bp region, a total of 10,622 genes were differentially expressed between fertile and sterile floral buds; 4,774 and 5,848 genes were up-regulated over 2-fold in fertile and sterile buds, respectively. However, the expression of 1,413 and 199 genes showed fertile and sterile bud-specific features, respectively. Genes expressed specifically in fertile buds, possibly GMS-related genes, included homologs of several Arabidopsis male sterility-related genes, genes associated with the cell wall and synthesis of its surface proteins, pollen wall and coat components, signaling components, and nutrient supplies. However, most early genes for pollen development, genes for primexine and callose formation, and genes for pollen maturation and anther dehiscence showed no difference in expression between fertile and sterile buds. Some of the known genes associated with Arabidopsis pollen development showed similar expression patterns to those seen in this study, while others did not. BrbHLH89 and BrMYP99 are putative GMS genes. Additionally, 17 novel genes identified only in B. rapa were specifically and highly expressed only in fertile buds, implying the possible involvement in male fertility. All data suggest that Chinese cabbage GMS might be controlled by genes acting in post-meiotic tapetal development that are different from those known to be associated with Arabidopsis male sterility.

  12. Cell wall degrading enzyme induced rice innate immune responses are suppressed by the type 3 secretion system effectors XopN, XopQ, XopX and XopZ of Xanthomonas oryzae pv. oryzae.

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    Dipanwita Sinha

    Full Text Available Innate immune responses are induced in plants and animals through perception of Damage Associated Molecular Patterns. These immune responses are suppressed by pathogens during infection. A number of studies have focussed on identifying functions of plant pathogenic bacteria that are involved in suppression of Pathogen Associated Molecular Pattern induced immune responses. In comparison, there is very little information on functions used by plant pathogens to suppress Damage Associated Molecular Pattern induced immune responses. Xanthomonasoryzae pv. oryzae, a gram negative bacterial pathogen of rice, secretes hydrolytic enzymes such as LipA (Lipase/Esterase that damage rice cell walls and induce innate immune responses. Here, we show that Agrobacterium mediated transient transfer of the gene for XopN, a X. oryzae pv. oryzae type 3 secretion (T3S system effector, results in suppression of rice innate immune responses induced by LipA. A xopN (- mutant of X. oryzae pv. oryzae retains the ability to suppress these innate immune responses indicating the presence of other functionally redundant proteins. In transient transfer assays, we have assessed the ability of 15 other X. oryzae pv. oryzae T3S secreted effectors to suppress rice innate immune responses. Amongst these proteins, XopQ, XopX and XopZ are suppressors of LipA induced innate immune responses. A mutation in any one of the xopN, xopQ, xopX or xopZ genes causes partial virulence deficiency while a xopN (- xopX (- double mutant exhibits a greater virulence deficiency. A xopN (- xopQ (- xopX (- xopZ (- quadruple mutant of X. oryzae pv. oryzae induces callose deposition, an innate immune response, similar to a X. oryzae pv. oryzae T3S(- mutant in rice leaves. Overall, these results indicate that multiple T3S secreted proteins of X. oryzae pv. oryzae can suppress cell wall damage induced rice innate immune responses.

  13. Morphological features and associated anomalies of schizencephaly in the clinical population: detailed analysis of MR images

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    Hayashi, N. [Department of Radiology, Faculty of Medicine, University of Tokyo (Japan); Department of Radiology, Section of Neuroradiology, University of California San Francisco, CA (United States); Tsutsumi, Y. [Department of Radiology, National Okura Hospital, Tokyo (Japan); Barkovich, A.J. [Department of Radiology, Section of Neuroradiology, University of California San Francisco, CA (United States)

    2002-05-01

    Although they are well documented in autopsy series, the macroscopic features and associated anomalies of schizencephalies have not been described in detail in a large clinical population. To assess the macroscopic findings of schizencephaly and the prevalence of associated findings, we conducted a retrospective MR analysis of a group of patients with schizencephaly. The MR studies of 35 patients with schizencephaly were retrospectively reviewed. The images were examined for the location and size of the schizencephalic cleft, the presence and location of associated polymicrogyria, and the presence, location, and severity of other brain anomalies. A total of 54 schizencephalic clefts were seen in the 35 patients. These clefts were unilateral in 18 (51%) patients and bilateral in 17 (49%) patients; three clefts were identified in two patients. Nine clefts (17%) had fused lips and 45 had separated-lip clefts (83%). Polymicrogyria was present inside 23 clefts (43%), while subependymal heterotopias were present at the cleft orifice in 27 clefts (50%). Polymicrogyria was identified outside the cleft, both adjacent to and remote from the cleft, in 23 patients (66%). Abnormal cerebral white-matter signal intensity was present in seven patients (20%), while white-matter volume diminution was noted in all patients. Ventricular diverticula with mass effect, roofing membranes, remnant floors, and cord-like remnants were present in 12, 1, 11, and 3 patients, respectively. Our results show that the spectrum of macroscopic findings in schizencephaly includes fused-lip and separated-lip clefts, polymicrogyric and non-polymicrogyric cleft linings, cyst-like diverticula and membranous structures, and subependymal heterotopia at the cleft. Concomitant anomalies are polymicrogyria outside the cleft, white-matter diminution, septal and optic pathway anomalies, callosal anomalies and hippocampal anomalies. Unilateral and bilateral clefts occur in a nearly equal frequency in the clinical

  14. The Xanthomonas campestris pv. vesicatoria Type-3 Effector XopB Inhibits Plant Defence Responses by Interfering with ROS Production.

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    Johannes Peter Roman Priller

    Full Text Available The bacterial pathogen Xanthomonas campestris pv. vesicatoria 85-10 (Xcv translocates about 30 type-3 effector proteins (T3Es into pepper plants (Capsicum annuum to suppress plant immune responses. Among them