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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. 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

  3. Isolated complete corpus callosal agenesis

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    Jaiganesh S, Venkateshwaran A, Naresh Kumar C, Rajasekhar KV

    2014-11-01

    Full Text Available Isolated complete corpus callosal agenesis is a rare entity. Usually this condition will be an associated finding in other syndromes. 3 month old male child came with complaints of deformed foot on both sides, not having a social smile and neck holding. Patient referred to the Radiology department for MRI brain which showed complete absence of corpus callosum, widely separated and parallely placed lateral ventricles, colpocephaly, high riding of 3rd ventricle and absence of cingulate gyrus and radial arrangement of gyri along the interhemispheric fissure. Hence it was reported as isolated complete corpus callosal agenesis and this article describes the Embryogenesis, anatomy, developmental anomalies and its clinical manifestations & prognosis.

  4. Isolated complete corpus callosal agenesis

    OpenAIRE

    Jaiganesh S, Venkateshwaran A, Naresh Kumar C, Rajasekhar KV

    2014-01-01

    Isolated complete corpus callosal agenesis is a rare entity. Usually this condition will be an associated finding in other syndromes. 3 month old male child came with complaints of deformed foot on both sides, not having a social smile and neck holding. Patient referred to the Radiology department for MRI brain which showed complete absence of corpus callosum, widely separated and parallely placed lateral ventricles, colpocephaly, high riding of 3rd ventricle and absence of cingulate gyrus an...

  5. Parkinsonism "Plus" Syndrome With Incidental Corpus Callosal Agenesis

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    Shanbhogue K R

    1999-01-01

    Full Text Available A case of Parkinsonism ′Plus′ syndrome with cranial CT scan and MRI showing corpus callosal agenesis is reported. There were no clinical signs of callosal separation. The causes for the discrepancies between the lack of clinical signs of callosal separation and imaging appearances are discussed. The callosal agenesis is in all probability incidental.

  6. Parkinsonism "Plus" Syndrome With Incidental Corpus Callosal Agenesis

    OpenAIRE

    Shanbhogue K R; Bennett D; Shankar V; Murugesan S; Stephen A S K; Karnan B; Srikanth S

    1999-01-01

    A case of Parkinsonism ′Plus′ syndrome with cranial CT scan and MRI showing corpus callosal agenesis is reported. There were no clinical signs of callosal separation. The causes for the discrepancies between the lack of clinical signs of callosal separation and imaging appearances are discussed. The callosal agenesis is in all probability incidental.

  7. Callosal agenesis followed postnatally after prenatal diagnosis.

    Science.gov (United States)

    Imataka, George; Nakagawa, Eiji; Kuwashima, Shigeko; Watanabe, Hiroshi; Yamanouchi, Hideo; Arisaka, Osamu

    2006-09-01

    Callosal agenesis is a congenital brain anomaly caused by embryonal hypogenesis of the corpus callosum. Concerning the neurological prognosis, epilepsy and motor disturbance are noted in some cases, while many cases are asymptomatic and the prognosis is good. We report a fetus tentatively diagnosed with hydrocephaly on prenatal echo-encephalography, which was performed without adequate explanation to and understanding of the parents. The parents had not expected an abnormality before the screening, and were subsequently not psychologically prepared for the discovery of the congenital brain anomaly on imaging. Moreover, they received no guidance on how to deal with any possible abnormalities. The pregnant mother was referred to our hospital. Prenatal MRI was performed after informed consent was obtained, and the fetus was diagnosed with callosal agenesis. The patient was followed for 5 years, and neurological development was normal. However, the parents have remained anxious while raising the child. Thus, the prenatal diagnosis of callosal agenesis in this case caused unnecessary mental burden to the parents. Here, we report the course of the case, and discuss the way prenatal ultrasonography should be used as a prenatal screening method, and the importance of counseling before the test.

  8. Visual interhemispheric communication and callosal connections of the occipital lobes.

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    Berlucchi, Giovanni

    2014-07-01

    Callosal connections of the occipital lobes, coursing in the splenium of the corpus callosum, have long been thought to be crucial for interactions between the cerebral hemispheres in vision in both experimental animals and humans. Yet the callosal connections of the temporal and parietal lobes appear to have more important roles than those of the occipital callosal connections in at least some high-order interhemispheric visual functions. The partial intermixing and overlap of temporal, parietal and occipital callosal connections within the splenium has made it difficult to attribute the effects of splenial pathological lesions or experimental sections to splenial components specifically related to select cortical areas. The present review describes some current contributions from the modern techniques for the tracking of commissural fibers within the living human brain to the tentative assignation of specific visual functions to specific callosal tracts, either occipital or extraoccipital.

  9. Callosal function in MS patients with mild and severe callosal damage as reflected by diffusion tensor imaging.

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    Warlop, Nele P; Fieremans, Els; Achten, Eric; Debruyne, Jan; Vingerhoets, Guy

    2008-08-21

    In this study, callosal function was behaviourally tested in MS patients with a redundant stimuli task. Reaction times to uni- and bilateral visual stimuli are recorded. Normal subjects respond faster to bilateral than to unilateral stimuli. This effect is called the redundancy gain effect. In patients with agenesis of the corpus callosum, the redundancy gain exceeds that predicted by probability summation, suggesting a mediating influence of the corpus callosum in healthy controls. The aim of this study is to investigate the effect of callosal damage on the redundancy gain in MS patients by investigating the probability summation model. Seventeen MS patients and as many matched healthy controls performed the redundancy gain task. In order to objectify callosal damage in our MS group, diffusion tensor imaging (DTI) derived measures such as fractional anisotropy (FA) and mean diffusivity (MD) in the corpus callosum were obtained. Callosal FA and MD significantly differed in our MS group compared to the healthy controls, indicating pathological callosal involvement. Since the amount of callosal damage was highly variable within the MS group, the MS cohort was split into a low and a high callosal-injured group as quantified by FA. The high FA group performed like the healthy controls, whereas violations of the probability (race) model were found for the low FA group. We conclude that behavioural measures obtained by the redundancy gain paradigm reflect callosal pathology in MS as measured by DTI.

  10. Early visual evoked potentials in callosal agenesis.

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    Barr, Melodie S; Hamm, Jeff P; Kirk, Ian J; Corballis, Michael C

    2005-11-01

    Three participants with callosal agenesis and 12 neurologically normal participants were tested on a simple reaction time task, with visual evoked potentials collected using a high-density 128-channel system. Independent-components analyses were performed on the averaged visual evoked potentials to isolate the components of interest. Contrary to previous research with acallosals, evidence of ipsilateral activation was present in all 3 participants. Although ipsilateral visual components were present in all 4 unilateral conditions in the 2 related acallosal participants, in the 3rd, these were present only in the crossed visual field-hand conditions and not in the uncrossed conditions. Suggestions are made as to why these results differ from earlier findings and as to the neural mechanisms facilitating this ipsilateral activation.

  11. Selective serotonergic excitation of callosal projection neurons

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    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].

    Science.gov (United States)

    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. Anterior commissure absence without callosal agenesis: a new brain malformation.

    Science.gov (United States)

    Mitchell, T N; Stevens, J M; Free, S L; Sander, J W; Shorvon, S D; Sisodiya, S M

    2002-04-23

    The authors report a novel human brain malformation characterized by the absence of the anterior commissure without callosal agenesis, but associated with gross unilateral panhemispheric malformation incorporating subependymal heterotopia, subcortical heterotopia, and gyral abnormalities including temporal malformation and polymicrogyria. In contrast, a normal anterior commissure was found in 125 control subjects and in 113 other subjects with a range of brain malformations.

  14. Enhanced redundancy gain in schizophrenics: a correlate of callosal dysfunction?

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    Florio, Vincenzo; Marzi, Carlo A; Girelli, Andrea; Savazzi, Silvia

    2008-09-01

    An abnormal pattern of hemispheric asymmetry, possibly as a result of disturbed interhemispheric communication, is widely, albeit by no means unanimously, held as a major cause of schizophrenia. To behaviourally test interhemispheric communication in schizophrenia we used a task that has been shown to be a reliable indicator of callosal functioning, namely, the redundant signals effect (RSE). It consists of the speeding of simple reaction time when responding to double as opposed to single visual stimuli. When the stimuli in a pair are presented to different hemispheres patients who underwent total commissurotomy or suffer from callosal agenesis show a paradoxically enhanced RSE with respect to healthy controls. Therefore, if schizophrenia patients have a callosal abnormality they ought to show a similar effect. In three experiments we tested a total of 55 patients with a diagnosis of schizophrenia and 51 healthy controls. In Experiment 1 we presented unilateral single stimuli and bilateral simultaneous double stimuli. The RSE was reliably larger in schizophrenics than in controls. In Experiment 2 the temporal interval between the two stimuli in a pair was varied. We found that while in controls the RSE disappeared with interstimulus intervals longer than 17ms, in schizophrenia patients there was a RSE only for simultaneous double stimuli. Finally, in Experiment 3 we found that there was no enhanced redundancy gain in schizophrenics when the double stimuli were presented to one and the same hemisphere, and therefore, with no need for callosal transmission. All in all, the present results provide evidence of a callosal dysfunction in schizophrenia that impairs interhemispheric integration.

  15. The role of the anterior commissure in callosal agenesis.

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    Barr, Melodie S; Corballis, Michael C

    2002-10-01

    Two individuals with callosal agenesis (J.P. and M.M.) and 10 neurologically normal participants were tested on tasks requiring interhemispheric visual integration. M.M., whose anterior commissure was within normal limits, was much worse at matching colors and letters between visual fields than within visual fields, whereas J.P., whose anterior commissure was greatly enlarged, showed no evidence of interhemispheric disconnection. This suggests that in some cases of callosal agenesis, probably a minority, an enlarged anterior commissure may compensate for the lack of the corpus callosum. Neither acallosal participant showed interhemispheric disconnection on tasks requiring integration of location and orientation, however, suggesting that the anterior commissure plays no role in such tasks. These tasks may depend on subcortical commissures, such as the intertectal commissure.

  16. Electrophysiological Correlates of Morphological Neuroplasticity in Human Callosal Dysgenesis.

    Science.gov (United States)

    Lazarev, Vladimir V; de Carvalho Monteiro, Myriam; Vianna-Barbosa, Rodrigo; deAzevedo, Leonardo C; Lent, Roberto; Tovar-Moll, Fernanda

    2016-01-01

    In search for the functional counterpart of the alternative Probst and sigmoid bundles, considered as morphological evidence of neuroplasticity in callosal dysgenesis, electroencephalographic (EEG) coherence analysis was combined with high resolution and diffusion tensor magnetic resonance imaging. Data of two patients with callosal agenesis, plus two with typical partial dysgenesis with a remnant genu, and one atypical patient with a substantially reduced genu were compared to those of fifteen neurotypic controls. The interhemispheric EEG coherence between homologous nontemporal brain regions corresponded to absence or partial presence of callosal connections. A generalized coherence reduction was observed in complete acallosal patients, as well as coherence preservation in the anterior areas of the two patients with a remnant genu. jThe sigmoid bundles found in three patients with partial dysgenesis correlated with augmented EEG coherence between anterior regions of one hemisphere and posterior regions of the other. These heterologous (crossed) interhemispheric connections were asymmetric in both imaging and EEG patterns, with predominance of the right-anterior-to-left-posterior connections over the mirror ones. The Probst bundles correlated with higher intrahemispheric long-distance coherence in all patients. The significant correlations observed for the delta, theta and alpha bands indicate that these alternative pathways are functional, although the neuropsychological nature of this function is still unknown.

  17. Behavioral Disorders in Association with Posterior Callosal and Frontal Cerebral Infarction

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    J. P. Lejeune

    1993-01-01

    Full Text Available Behavioral disorders were a prominent clinical feature after the surgical treatment of an anterior communicating artery aneurysm rupture in a 44-year-old man. Callosal apraxia was associated with an alien hand. The latter remained 1 year after surgery while diagonistic apraxia disappeared after 3 months. Other callosal signs included left agraphia, tactile anomia and auditory suppression. MRI revealed posterior callosal infarction and a right frontal infarct. The association of diagonistic apraxia and alien hand is rarely reported.

  18. 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).

  19. 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 w

  20. Diffusion Weighted Callosal Integrity Reflects Interhemispheric Communication Efficiency in Multiple Sclerosis

    Science.gov (United States)

    Warlop, Nele P.; Achten, Eric; Debruyne, Jan; Vingerhoets, Guy

    2008-01-01

    We aimed to investigate the relation between damage in the corpus callosum and the performance on an interhemispheric communication task in patients with multiple sclerosis (MS). Relative callosal lesion load defined as the ratio between callosal area and the total lesion load in the total corpus callosum, and the diffusion tensor imaging (DTI)…

  1. Sex differences in the incidence of total callosal agenesis in BALB/cCF mice.

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    Manhães, Alex C; Medina, Alexandre E; Schmidt, Sergio L

    2002-06-14

    Corpus callosum (CC) development and adult morphology seems to be affected by sex. Here we analyzed the incidence of total callosal agenesis in 341 adult male and 318 female BALB/cCF mice. This strain of mice presents total or partial callosal agenesis in approximately 20-30% of its population. No significant differences were found in overall distributions of CC lengths and in average callosal lengths (totally acallosal excluded) between male and female mice. However, a highly significant difference in the incidence of total callosal agenesis was demonstrated: 18% (n=56) of the female mice presented such trait as opposed to 10% of males (n=34). This last result suggests that sex is a relevant factor in callosal development in its earliest stages of formation.

  2. Paradoxically greater interhemispheric transfer deficits in partial than complete callosal agenesis.

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    Aglioti, S; Beltramello, A; Tassinari, G; Berlucchi, G

    1998-10-01

    Symptoms of interhemispheric disconnection are typically much less severe in callosal agenesis than after surgical section of the corpus callosum. Sperry [Sperry, R. W., Plasticity of neural maturation. Developmental Biology, 1968, 2 (Suppl.), 306-327.] has attributed this difference to two interconnected factors: (1) the callosal section is usually performed after the brain has lost the maximal degree of functional plasticity associated with the early stages of development and (2) the removal of an already formed structure is more disruptive for functional brain organization than the failure of the same structure to develop. It has been suggested that functional compensation is less efficient if callosal agenesis is partial rather than complete [Dennis, M., Impaired sensory and motor differentiation with corpus callosum agenesis: A lack of callosal inhibition during ontogeny? Neuropsychologia, 1976, 14, 455-469.]. This suggestion is supported by the present findings of partial left-hand anomia, partial left-field alexia and poor tactile cross-localization in a subject with a congenital absence of the posterior part of the corpus callosum due to an arteriovenous malformation. In agreement with many previous studies, similar, though more severe, symptoms of interhemispheric disconnection were found in a subject with a complete section of the corpus callosum, but not in a subject with complete callosal agenesis. Praxic control of the left hand on verbal commands was severely deficient in the callosotomy subject, but it was normal in the subject with callosal hypogenesis. The lesser degree of compensation in partial compared to complete callosal agenesis may be explained by a reduced pressure to develop extracallosal means of interhemispheric communication, contingent on the partial existence of callosal connections, as well as by the later occurrence in development of the causes of callosal hypogenesis compared to those of total callosal agenesis.

  3. Callosal apraxia: a 34-year follow-up study.

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    Falchook, Adam D; Watson, Robert T; Heilman, Kenneth M

    2016-06-01

    Loss of ability of the left upper limb (LUL) to correctly produce spatial and temporal components of skilled purposeful movements was reported 34 years ago in a woman with a callosal infarction. To learn about recovery, we recently reexamined this woman. This woman was tested for ideomotor apraxia by asking her to pantomime to command and to seeing pictures of tools. Whereas she performed normally with her right upper limb, her LUL remained severely apraxic, making many spatial (postural and movement) errors. Initially, she did not reveal loss of finger-hand deftness (limb-kinetic apraxia), and when tested again with the coin rotation task, her left hand performance was normal. Without vision, she could name objects placed in her left hand but not name numbers written in this hand. Since this woman had a callosal lesion, failure to recover cannot be accounted for by left hemisphere inhibition of her right hemisphere. Although failure for her LUL to improve may have been related to not using her LUL for skilled actions, her right hemisphere was able to observe transitive actions, and this failure of her LUL to produce skilled purposeful movements suggests her right hemisphere may have not had the capacity to learn these movement representations. Without vision, her ability to recognize objects with her left hand, but not numbers written on her left palm, suggests graphesthesia may require that her left hand did not have access to movement representations important for programming these numbers when writing.

  4. Increased callose deposition in plants lacking DYNAMIN-RELATED PROTEIN 2B is dependent upon POWDERY MILDEW RESISTANT 4.

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    Leslie, Michelle E; Rogers, Sean W; Heese, Antje

    2016-11-01

    Callose deposition within the cell wall is a well-documented plant immune response to pathogenic organisms as well as to pathogen-/microbe- associated molecular patterns (P/MAMPs). However, the molecular mechanisms that modulate pathogen-induced callose deposition are less understood. We reported previously that Arabidopsis plants lacking the vesicle trafficking component DYNAMIN-RELATED PROTEIN 2B (DRP2B) display increased callose deposition in response to the PAMP flg22. Here, we show that increased number of flg22-induced callose deposits in drp2b leaves is fully dependent on the callose synthase POWDERY MILDEW RESISTANT 4 (PMR4). We propose that in addition to functioning in flg22-induced endocytosis of the plant receptor, FLAGELLIN SENSING 2, DRP2B may regulate the trafficking of proteins involved in callose synthesis, such as PMR4, and/or callose degradation.

  5. Abnormal interhemispheric motor interactions in patients with callosal agenesis.

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    Genç, Erhan; Ocklenburg, Sebastian; Singer, Wolf; Güntürkün, Onur

    2015-10-15

    During unilateral hand movements the activity of the contralateral primary motor cortex (cM1) is increased while the activity of the ipsilateral M1 (iM1) is decreased. A potential explanation for this asymmetric activity pattern is transcallosal cM1-to-iM1 inhibitory control. To test this hypothesis, we examined interhemispheric motor inhibition in acallosal patients. We measured fMRI activity in iM1 and cM1 in acallosal patients during unilateral hand movements and compared their motor activity pattern to that of healthy controls. In controls, fMRI activation in cM1 was significantly higher than in iM1, reflecting a normal differential task-related M1 activity. Additional functional connectivity analysis revealed that iM1 activity was strongly suppressed by cM1. Furthermore, DTI analysis indicated that this contralaterally induced suppression was mediated by microstructural properties of specific callosal fibers interconnecting both M1s. In contrast, acallosal patients did not show a clear differential activity pattern between cM1 and iM1. The more symmetric pattern was due to an elevated task-related iM1 activity in acallosal patients, which was significantly higher than iM1 activity in a subgroup of gender and age-matched controls. Also, interhemispheric motor suppression was completely absent in acallosal patients. These findings suggest that absence of callosal connections reduces inhibitory interhemispheric motor interactions between left and right M1. This effect may reveal novel aspects of mechanisms in communication of two hemispheres and establishment of brain asymmetries in general.

  6. Clinical features and associated abnormalities in children and adolescents with corpus callosal anomalies.

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    Kim, Young Uhk; Park, Eun Sook; Jung, Soojin; Suh, Miri; Choi, Hyo Seon; Rha, Dong-Wook

    2014-02-01

    Callosal anomalies are frequently associated with other central nervous system (CNS) and/or somatic anomalies. We retrospectively analyzed the clinical features of corpus callosal agenesis/hypoplasia accompanying other CNS and/or somatic anomalies. We reviewed the imaging and clinical information of patients who underwent brain magnetic resonance imaging in our hospital, between 2005 and 2012. Callosal anomalies were isolated in 13 patients, accompanied by other CNS anomalies in 10 patients, associated with only non-CNS somatic anomalies in four patients, and with both CNS and non-CNS abnormalities in four patients. Out of 31 patients, four developed normally, without impairments in motor or cognitive functions. Five of nine patients with cerebral palsy were accompanied by other CNS and/or somatic anomalies, and showed worse Gross Motor Function Classification System scores, compared with the other four patients with isolated callosal anomaly. In addition, patients with other CNS anomalies also had a higher seizure risk.

  7. Cerebral and callosal organisation in a right hemisphere dominant "split brain" patient.

    OpenAIRE

    Lutsep, H.L.; Wessinger, C M; Gazzaniga, M S

    1995-01-01

    Patients described in previous reports who have undergone corpus callostomy for control of seizures have been left hemisphere dominant for language. To determine the hemispheric localisation (and possible coexistence) of language and traditional right hemisphere skills in reversed dominance, the first right hemisphere dominant corpus callostomy patient was studied. Localisation of callosal functions was also investigated, as MRI showed 1.5 cm of spared callosal body. The patient, KO, a 15 yea...

  8. Language lateralization in a patient with temporal lobe epilepsy and callosal agenesis.

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    Alsaadi, Taoufik; Shahrour, Tarek M

    2015-01-01

    The corpus callosum has been proposed as a mechanism of interhemispheric inhibition that allows language dominance to develop [1]. Callosal agenesis or dysgenesis provides a test of this hypothesis, as patients lacking a normal corpus callosum should also lack normal language lateralization [2]. We report pre- and postoperative functional magnetic resonance imaging (fMRI) and neuropsychological testing in a patient with partial callosal agenesis who underwent a right temporal lobectomy for medically refractory seizures.

  9. Language lateralization in a patient with temporal lobe epilepsy and callosal agenesis

    Directory of Open Access Journals (Sweden)

    Taoufik Alsaadi

    2015-01-01

    Full Text Available The corpus callosum has been proposed as a mechanism of interhemispheric inhibition that allows language dominance to develop [1]. Callosal agenesis or dysgenesis provides a test of this hypothesis, as patients lacking a normal corpus callosum should also lack normal language lateralization [2]. We report pre- and postoperative functional magnetic resonance imaging (fMRI and neuropsychological testing in a patient with partial callosal agenesis who underwent a right temporal lobectomy for medically refractory seizures.

  10. Language lateralization in a patient with temporal lobe epilepsy and callosal agenesis

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    Taoufik Alsaadi; Shahrour, Tarek M.

    2014-01-01

    The corpus callosum has been proposed as a mechanism of interhemispheric inhibition that allows language dominance to develop [1]. Callosal agenesis or dysgenesis provides a test of this hypothesis, as patients lacking a normal corpus callosum should also lack normal language lateralization [2]. We report pre- and postoperative functional magnetic resonance imaging (fMRI) and neuropsychological testing in a patient with partial callosal agenesis who underwent a right temporal lobectomy for me...

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

    OpenAIRE

    Niwa, Tetsu; Linda S de Vries; Manten, GTR; Lequin, Maarten; Cuppen, Inge; Shibasaki, Jun; Aida, Noriko

    2016-01-01

    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 accompanied with malformations of cortical development (MCD). We report magnetic resonance imaging findings of three infants with an interhemispheric lipoma, associated with a callosal anomaly, and MCD...

  12. Elevated early callose deposition results in complete penetration resistance to powdery mildew in Arabidopsis.

    Science.gov (United States)

    Ellinger, Dorothea; Naumann, Marcel; Falter, Christian; Zwikowics, Claudia; Jamrow, Torsten; Manisseri, Chithra; Somerville, Shauna C; Voigt, Christian A

    2013-03-01

    A common response by plants to fungal attack is deposition of callose, a (1,3)-β-glucan polymer, in the form of cell wall thickenings called papillae, at site of wall penetration. While it has been generally believed that the papillae provide a structural barrier to slow fungal penetration, this idea has been challenged in recent studies of Arabidopsis (Arabidopsis thaliana), where fungal resistance was found to be independent of callose deposition. To the contrary, we show that callose can strongly support penetration resistance when deposited in elevated amounts at early time points of infection. We generated transgenic Arabidopsis lines that express POWDERY MILDEW RESISTANT4 (PMR4), which encodes a stress-induced callose synthase, under the control of the constitutive 35S promoter. In these lines, we detected callose synthase activity that was four times higher than that in wild-type plants 6 h post inoculation with the virulent powdery mildew Golovinomyces cichoracearum. The callose synthase activity was correlated with enlarged callose deposits and the focal accumulation of green fluorescent protein-tagged PMR4 at sites of attempted fungal penetration. We observed similar results from infection studies with the nonadapted powdery mildew Blumeria graminis f. sp. hordei. Haustoria formation was prevented in resistant transgenic lines during both types of powdery mildew infection, and neither the salicylic acid-dependent nor jasmonate-dependent pathways were induced. We present a schematic model that highlights the differences in callose deposition between the resistant transgenic lines and the susceptible wild-type plants during compatible and incompatible interactions between Arabidopsis and powdery mildew.

  13. Differences in early callose deposition during adapted and non-adapted powdery mildew infection of resistant Arabidopsis lines.

    Science.gov (United States)

    Naumann, Marcel; Somerville, Shauna; Voigt, Christian

    2013-06-01

    The deposition of callose, a (1,3)-β-glucan cell wall polymer, can play an essential role in the defense response to invading pathogens. We could recently show that Arabidopsis thaliana lines with an overexpression of the callose synthase gene PMR4 gained complete penetration resistance to the adapted powdery mildew Golovinomyces cichoracearum and the non-adapted powdery mildew Blumeria graminis f. sp hordei. The penetration resistance is based on the transport of the callose synthase PMR4 to the site of attempted fungal penetration and the subsequent formation of enlarged callose deposits. The deposits differed in their total diameter comparing both types of powdery mildew infection. In this study, further characterization of these callose deposits revealed that size differences were especially pronounced in the core region of the deposits. This suggests that specific, pathogen-dependent factors exist, which might regulate callose synthase transport to the core region of forming deposits.

  14. Visual callosal connections: role in visual processing in health and disease.

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    Bocci, Tommaso; Pietrasanta, Marta; Cerri, Chiara; Restani, Laura; Caleo, Matteo; Sartucci, Ferdinando

    2014-01-01

    Visual cortical areas in the two sides of the brain are interconnected by interhemispheric fibers passing through the splenium of the corpus callosum. In this review, we summarize data concerning the anatomical features of visual callosal connections, their roles in basic visual processing, and how their alterations contribute to visual deficits in different human neuropathologies. Splenial fibers represent a population of excitatory axons with varying diameters, which interconnect cortical columns with similar functional properties (i.e., same orientation selectivity) in the two hemispheres. Their branches activate simultaneously distinct iso-oriented columns in the contralateral hemisphere, thus mediating forms of stimulus-dependent interhemispheric synchronization. Callosal branches also make synapses onto GABAergic cells, resulting in an inhibitory modulation of visual processing that involves both iso-oriented and cross-oriented cortical networks. Interhemispheric inhibition appears to predominate at short latencies following callosal activation, whereas excitation becomes more robust with increasing delays. These callosal effects are dynamically adapted to the incoming visual activity, so that stimuli providing only weak afferent input are facilitated by callosal pathways, whereas strong visual input via the retinogeniculate pathway tends to be offset by transcallosal inhibition. We also review data highlighting the contribution of callosal input activity to maturation of visual function during early 'critical periods' in brain development and describe how interhemispheric transfer of visual information is rerouted in cases of callosal agenesis or following splenial damage. Finally, we provide an overview of alterations in splenium anatomy or function that may be at the basis of visual defects in several pathologic conditions.

  15. Sound lateralization in subjects with callosotomy, callosal agenesis, or hemispherectomy.

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    Hausmann, Markus; Corballis, Michael C; Fabri, Mara; Paggi, Aldo; Lewald, Jörg

    2005-10-01

    The question of whether there is a right-hemisphere dominance in the processing of auditory spatial information in human cortex as well as the role of the corpus callosum in spatial hearing functions is still a matter of debate. Here, we approached this issue by investigating two late-callosotomized subjects and one subject with agenesis of the corpus callosum, using a task of sound lateralization with variable interaural time differences. For comparison, three subjects with left or right hemispherectomy were also tested by employing identical methods. Besides a significant reduction in their acuity, subjects with total or partial section of the corpus callosum exhibited a considerable leftward bias of sound lateralization compared to normal controls. No such bias was found in the subject with callosal agenesis, but merely a marginal reduction of general acuity. Also, one subject with complete resection of the left cerebral cortex showed virtually normal performance, whereas another subject with left hemispherectomy and one subject with right hemispherectomy exhibited severe deficits, with almost total loss of sound-lateralization ability. The results obtained in subjects with callosotomy indicate that the integrity of the corpus callosum is not indispensable for preservation of sound-lateralization ability. On the other hand, transcallosal interhemispheric transfer of auditory information obviously plays a significant role in spatial hearing functions that depend on binaural cues. Moreover, these data are compatible with the general view of a dominance of the right cortical hemisphere in auditory space perception.

  16. Depletion of Inositol Polyphosphate 4-Phosphatase II Suppresses Callosal Axon Formation in the Developing Mice.

    Science.gov (United States)

    Ji, Liting; Kim, Nam-Ho; Huh, Sung-Oh; Rhee, Hae Jin

    2016-06-30

    The corpus callosum is a bundle of nerve fibers that connects the two cerebral hemispheres and is essential for coordinated transmission of information between them. Disruption of early stages of callosal development can cause agenesis of the corpus callosum (AgCC), including both complete and partial callosal absence, causing mild to severe cognitive impairment. Despite extensive studies, the etiology of AgCC remains to be clarified due to the complicated mechanism involved in generating AgCC. The biological function of PI3K signaling including phosphatidylinositol-3,4,5-trisphosphate is well established in diverse biochemical processes including axon and dendrite morphogenesis, but the function of the closely related phosphatidylinositol-3,4,-bisphosphate (PI(3,4)P2) signaling, particularly in the nervous system, is largely unknown. Here, we provide the first report on the role of inositol polyphosphate 4-phosphatase II (INPP4B), a PI(3,4)P2 metabolizing 4-phosphatase in the regulation of callosal axon formation. Depleting INPP4B by in utero electroporation suppressed medially directed callosal axon formation. Moreover, depletion of INPP4B significantly attenuated formation of Satb2-positive pyramidal neurons and axon polarization in cortical neurons during cortical development. Taken together, these data suggest that INPP4B plays a role in the regulating callosal axon formation by controlling axon polarization and the Satb2-positive pyramidal neuron population. Dysregulation of INPP4B during cortical development may be implicated in the generation of partial AgCC.

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

    Science.gov (United States)

    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.

  18. Isolated cystic lesion of the callosal genu after traumatic brain injury.

    Science.gov (United States)

    Kato, Toru; Okumura, Akihisa; Tsuji, Takeshi; Emi, Misugi; Natsume, Jun

    2012-06-01

    We report the case of a 17-month-old infant who developed an isolated cystic lesion of the callosal genu as a unique lesion of traumatic axonal injury (TAI). Although one of the most common sites of TAI is the corpus callosum, there have been no reports describing the lesion seen in our patient. Brain computed tomography findings were normal on the day of the traffic accident. After 3 months, brain magnetic resonance imaging showed an isolated cystic lesion of the callosal genu that had the appearance of a cystic cavity. This lesion decreased in size 16 months later. The neuroimaging findings of this patient suggest that an isolated cystic lesion of the callosal genu could appear as a unique form of TAI in infants after traumatic brain injury (TBI), but it is nevertheless important to attend to such lesions in children with TBI.

  19. 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...... mildew resulted in appositions that enlarged inversely to their size in the respective varieties when inoculated without carborundum treatment. Aphids sucking the leaves resulted in rows of callose containing spots along the anticlinal cell walls. The spots were larger in the ml-o mutant than...... in the mother variety. Callose was deposited in connection with the pleiotropic necrotic spotting in barleys with the ml-o gene. Modification of the necrotic spotting by crossing the ml-o gene into other gene backgrounds did not result in any change in the size of appositions upon inoculation with powdery...

  20. 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.

  1. 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

    callosal projecting neurons. There was significant impairment of retrograde labeling of NeuN-positive callosal projecting neurons and reduction in the labelling of their transcallosal axons. These data demonstrate a novel paradigm of cortical and callosal neuropathology in a mouse model of MS, perpetuated...

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

    Science.gov (United States)

    Niwa, Tetsu; de Vries, Linda S; Manten, Gwendolyn T R; Lequin, Maarten; Cuppen, Inge; Shibasaki, Jun; Aida, Noriko

    2016-04-01

    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 accompanied with malformations of cortical development (MCD). We report magnetic resonance imaging findings of three infants with an interhemispheric lipoma, associated with a callosal anomaly, and MCD: two infants with nodular interhemispheric lipoma, agenesis of the corpus callosum, and polymicrogyria, and one infant with interhemispheric curvilinear lipoma, hypoplasia of the corpus callosum, and heterotopias. An association was suggested regarding the occurrence of these malformations.

  3. 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

    . This is the 1st case where the effect of callose refers to the action of a specific gene. Six susceptible Japanese varieties formed large appositions but they were initiated as late as in other susceptible varieties, and their color was paler than in other barleys. Nine Hordeum spp. [H. capense, H. chilense, H...

  4. Magnetic resonance imaging and histological studies of corpus callosal and hippocampal abnormalities linked to doublecortin deficiency.

    Science.gov (United States)

    Kappeler, Caroline; Dhenain, Marc; Phan Dinh Tuy, Françoise; Saillour, Yoann; Marty, Serge; Fallet-Bianco, Catherine; Souville, Isabelle; Souil, Evelyne; Pinard, Jean-Marc; Meyer, Gundela; Encha-Razavi, Ferechté; Volk, Andreas; Beldjord, Cherif; Chelly, Jamel; Francis, Fiona

    2007-01-10

    Mutated doublecortin (DCX) gives rise to severe abnormalities in human cortical development. Adult Dcx knockout mice show no major neocortical defects but do have a disorganized hippocampus. We report here the developmental basis of these hippocampal abnormalities. A heterotopic band of neurons was identified starting at E17.5 in the CA3 region and progressing throughout the CA1 region by E18.5. At neonatal stages, the CA1 heterotopic band was reduced, but the CA3 band remained unchanged, continuing into adulthood. Thus, in mouse, migration of CA3 neurons is arrested during development, whereas CA1 cell migration is retarded. On the Sv129Pas background, magnetic resonance imaging (MRI) also suggested abnormal dorsal hippocampal morphology, displaced laterally and sometimes rostrally and associated with medial brain structure abnormalities. MRI and cryosectioning showed agenesis of the corpus callosum in Dcx knockout mice on this background and an intermediate, partial agenesis in heterozygote mice. Wild-type littermates showed no callosal abnormalities. Hippocampal and corpus callosal abnormalities were also characterized in DCX-mutated human patients. Severe hippocampal hypoplasia was identified along with variable corpus callosal defects ranging from total agenesis to an abnormally thick or thin callosum. Our data in the mouse, identifying roles for Dcx in hippocampal and corpus callosal development, might suggest intrinsic roles for human DCX in the development of these structures.

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

    NARCIS (Netherlands)

    Niwa, Tetsu; de Vries, Linda S.; Manten, GTR; Lequin, Maarten; Cuppen, Inge; Shibasaki, Jun; Aida, Noriko

    2016-01-01

    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 acco

  6. Interhemispheric Connections between the Primary Visual Cortical Areas via the Anterior Commissure in Human Callosal Agenesis.

    Science.gov (United States)

    van Meer, Nathalie; Houtman, Anne C; Van Schuerbeek, Peter; Vanderhasselt, Tim; Milleret, Chantal; Ten Tusscher, Marcel P

    2016-01-01

    Aim: In humans, images in the median plane of the head either fall on both nasal hemi-retinas or on both temporal hemi-retinas. Interhemispheric connections allow cortical cells to have receptive fields on opposite sides. The major interhemispheric connection, the corpus callosum, is implicated in central stereopsis and disparity detection in front of the fixation plane. Yet individuals with agenesis of the corpus callosum may show normal stereopsis and disparity vergence. We set out to study a possible interhemispheric connection between primary visual cortical areas via the anterior commissure to explain this inconsistency because of the major role of these cortical areas in elaborating 3D visual perception. Methods: MRI, DTI and tractography of the brain of a 53-year old man with complete callosal agenesis and normal binocular single vision was undertaken. Tractography seed points were placed in both the right and the left V1 and V2. Nine individuals with both an intact corpus callosum and normal binocularity served as controls. Results: Interhemispheric tracts through the anterior commissure linking both V1 and V2 visual cortical areas bilaterally were indeed shown in the subject with callosal agenesis. All other individuals showed interhemispheric visual connections through the corpus callosum only. Conclusion: Callosal agenesis may result in anomalous interhemispheric connections of the primary visual areas via the anterior commissure. It is proposed here that these connections form as alternative to the normal callosal pathway and may participate in binocularity.

  7. Iron-dependent callose deposition adjusts root meristem maintenance to phosphate availability.

    Science.gov (United States)

    Müller, Jens; Toev, Theresa; Heisters, Marcus; Teller, Janine; Moore, Katie L; Hause, Gerd; Dinesh, Dhurvas Chandrasekaran; Bürstenbinder, Katharina; Abel, Steffen

    2015-04-20

    Plant root development is informed by numerous edaphic cues. Phosphate (Pi) availability impacts the root system architecture by adjusting meristem activity. However, the sensory mechanisms monitoring external Pi status are elusive. Two functionally interacting Arabidopsis genes, LPR1 (ferroxidase) and PDR2 (P5-type ATPase), are key players in root Pi sensing, which is modified by iron (Fe) availability. We show that the LPR1-PDR2 module facilitates, upon Pi limitation, cell-specific apoplastic Fe and callose deposition in the meristem and elongation zone of primary roots. Expression of cell-wall-targeted LPR1 determines the sites of Fe accumulation as well as callose production, which interferes with symplastic communication in the stem cell niche, as demonstrated by impaired SHORT-ROOT movement. Antagonistic interactions of Pi and Fe availability control primary root growth via meristem-specific callose formation, likely triggered by LPR1-dependent redox signaling. Our results link callose-regulated cell-to-cell signaling in root meristems to the perception of an abiotic cue.

  8. Callose (β-1,3 glucan is essential for Arabidopsis pollen wall patterning, but not tube growth

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    Maruyama Daisuke

    2005-10-01

    Full Text Available Abstract Background Callose (β-1,3 glucan separates developing pollen grains, preventing their underlying walls (exine from fusing. The pollen tubes that transport sperm to female gametes also contain callose, both in their walls as well as in the plugs that segment growing tubes. Mutations in CalS5, one of several Arabidopsis β-1,3 glucan synthases, were previously shown to disrupt callose formation around developing microspores, causing aberrations in exine patterning, degeneration of developing microspores, and pollen sterility. Results Here, we describe three additional cals5 alleles that similarly alter exine patterns, but instead produce fertile pollen. Moreover, one of these alleles (cals5-3 resulted in the formation of pollen tubes that lacked callose walls and plugs. In self-pollinated plants, these tubes led to successful fertilization, but they were at a slight disadvantage when competing with wild type. Conclusion Contrary to a previous report, these results demonstrate that a structured exine layer is not required for pollen development, viability or fertility. In addition, despite the presence of callose-enriched walls and callose plugs in pollen tubes, the results presented here indicate that callose is not required for pollen tube functions.

  9. Multiple non-cell-autonomous defects underlie neocortical callosal dysgenesis in Nfib-deficient mice

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    Sunn Nana

    2009-12-01

    Full Text Available Abstract Background Agenesis of the corpus callosum is associated with many human developmental syndromes. Key mechanisms regulating callosal formation include the guidance of axons arising from pioneering neurons in the cingulate cortex and the development of cortical midline glial populations, but their molecular regulation remains poorly characterised. Recent data have shown that mice lacking the transcription factor Nfib exhibit callosal agenesis, yet neocortical callosal neurons express only low levels of Nfib. Therefore, we investigate here how Nfib functions to regulate non-cell-autonomous mechanisms of callosal formation. Results Our investigations confirmed a reduction in glial cells at the midline in Nfib-/- mice. To determine how this occurs, we examined radial progenitors at the cortical midline and found that they were specified correctly in Nfib mutant mice, but did not differentiate into mature glia. Cellular proliferation and apoptosis occurred normally at the midline of Nfib mutant mice, indicating that the decrease in midline glia observed was due to deficits in differentiation rather than proliferation or apoptosis. Next we investigated the development of callosal pioneering axons in Nfib-/- mice. Using retrograde tracer labelling, we found that Nfib is expressed in cingulate neurons and hence may regulate their development. In Nfib-/- mice, neuropilin 1-positive axons fail to cross the midline and expression of neuropilin 1 is diminished. Tract tracing and immunohistochemistry further revealed that, in late gestation, a minor population of neocortical axons does cross the midline in Nfib mutants on a C57Bl/6J background, forming a rudimentary corpus callosum. Finally, the development of other forebrain commissures in Nfib-deficient mice is also aberrant. Conclusion The formation of the corpus callosum is severely delayed in the absence of Nfib, despite Nfib not being highly expressed in neocortical callosal neurons. Our

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

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    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

  11. 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.

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

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    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.

  13. Callosal atrophy in mild cognitive impairment and Alzheimer's disease: different effects in different stages.

    Science.gov (United States)

    Di Paola, Margherita; Luders, Eileen; Di Iulio, Fulvia; Cherubini, Andrea; Passafiume, Domenico; Thompson, Paul M; Caltagirone, Carlo; Toga, Arthur W; Spalletta, Gianfranco

    2010-01-01

    Alzheimer's Disease (AD) is a neurodegenerative disorder that mainly affects grey matter (GM). Nevertheless, a number of investigations have documented white matter (WM) pathology associated with AD. The corpus callosum (CC) is the largest WM fiber bundle in the human brain. It has been shown to be susceptible to atrophy in AD mainly as a correlate of Wallerian degeneration of commissural nerve fibers of the neocortex. The aim of this study was to investigate which callosal regions are affected and whether callosal degeneration is associated with the stage of the disease. For this purpose, we analyzed high-resolution MRI data of patients with amnesic mild cognitive impairment (MCI) (n=20), mild AD (n=20), severe AD (n=10), and of healthy controls (n=20). Callosal morphology was investigated applying two different structural techniques: mesh-based geometrical modeling methods and whole-brain voxel-based analyses. Our findings indicate significant reductions in severe AD patients compared to healthy controls in anterior (genu and anterior body) and posterior (splenium) sections. In contrast, differences between healthy controls and mild AD patients or amnesic MCI patients were less pronounced and did not survive corrections for multiple comparisons. When correlating anterior and posterior WM density of the CC with GM density of the cortex in the severe AD group, we detected significant positive relationships between posterior sections of the CC and the cortex. We conclude that callosal atrophy is present predominantly in the latest stage of AD, where two mechanisms might contribute to WM alterations in severe AD: the Wallerian degeneration in posterior subregions and the myelin breakdown process in anterior subregions.

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

    Science.gov (United States)

    Schneider, Christine; Helmstaedter, Christoph; Luders, Eileen; Thompson, Paul M; Toga, Arthur W; Elger, Christian; Weber, Bernd

    2014-01-01

    The main objective of this paper is to analyze the influence of mesial temporal lobe epilepsy (mTLE) 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 mTLE-patients was recruited. Intelligence was measured using the Wechsler-Adult Intelligence Scale Revised. 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 mTLE, 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 mTLE 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.

  15. 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.

  16. Diffusion-weighted imaging in fetuses with unilateral cortical malformations and callosal agenesis.

    Science.gov (United States)

    Glenn, O A; Quiroz, E M; Berman, J I; Studholme, C; Xu, D

    2010-06-01

    DWI was performed in fetuses with callosal agenesis and unilateral cortical malformations. ADC values were retrospectively measured in the developing white matter underlying the cortical malformation and compared with the corresponding contralateral white matter. In all 3 patients, ADC values were lower under the areas of cortical malformation compared with the normal contralateral side. Our findings suggest that there are structural differences in the developing white matter underlying areas of cortical malformation.

  17. The Syndrome of Frontonasal Dysplasia, Callosal Agenesis, Basal Encephalocele, and Eye Anomalies - Phenotypic and Aetiological Considerations.

    Science.gov (United States)

    Richieri-Costa, Antonio; Guion-Almeida, Maria Leine

    2004-01-01

    We report ten sporadic cases of Brazilian patients with facial midline defects, callosal agenesis, basal encephalocele, and ocular anomalies. This very rare cluster of anomalies has been well reported before. However, only until recently it is recognized as a syndrome belonging to frontonasal dysplasia spectrum. The ten cases confirm a distinct clinical entity and help to define the phenotype more precisely than previously. Up to now etiology remains unknown, although we conjecture that it is due to a mutation in TGIF gene.

  18. Variability in the distribution of callosal projection neurons in the adult rat parietal cortex.

    Science.gov (United States)

    Ivy, G O; Gould, H J; Killackey, H P

    1984-07-23

    Previous reports have shown that the barrel field area of the parietal cortex of the adult rat contains relatively few callosal projection neurons, even though callosal projection neurons are abundant in this cortical region in the neonatal rat. Furthermore, it has been shown that many of the callosal neurons which seem to disappear as the animal matures do not die, but project to ipsilateral cortical areas. These findings rely on the ability of retrograde transport techniques which utilize injections of horseradish peroxidase (HRP) or of fluorescent dyes into one hemisphere. We now show that several technical modifications of the HRP technique yield a wider distribution of HRP-containing neurons in the contralateral barrel field area of the adult rat than previously reported. These include implants of HRP pellets into transected axons of the corpus callosum, the addition of DMSO and nonidet P40 to Sigma VI HRP, wheat germ agglutinin HRP and the use of tetramethyl benzidine as the chromogen in the reaction procedure. Our findings have implications for transport studies in general and for the development of the cortical barrel field in particular.

  19. Neuroimaging techniques offer new perspectives on callosal transfer and interhemispheric communication.

    Science.gov (United States)

    Doron, Karl W; Gazzaniga, Michael S

    2008-09-01

    The brain relies on interhemispheric communication for coherent integration of cognition and behavior. Surgical disconnection of the two cerebral hemispheres has granted numerous insights into the functional organization of the corpus callosum (CC) and its relationship to hemispheric specialization. Today, technologies exist that allow us to examine the healthy, intact brain to explore the ways in which callosal organization relates to normal cognitive functioning and cerebral lateralization. The CC is organized in a topographical manner along its antero-posterior axis. Evidence from neuroimaging studies is revealing with greater specificity the function and the cortical projection targets of the topographically organized callosal subregions. The size, myelination and density of fibers in callosal subregions are related to function of the brain regions they connect: smaller fibers are slow-conducting and connect higher-order association areas; larger fibers are fast-conducting and connect visual, motor and secondary somotosensory areas. A decrease in fiber size and transcallosal connectivity might be related to a reduced need for interhemispheric communication due, in part, to increased intrahemispheric connectivity and specialization. Additionally, it has been suggested that lateralization of function seen in the human brain lies along an evolutionary continuum. Hemispheric specialization reduces duplication of function between the hemispheres. The microstructure and connectivity patterns of the CC provide a window for understanding the evolution of hemispheric asymmetries and lateralization of function. Here, we review the ways in which converging methodologies are advancing our understanding of interhemispheric communication in the normal human brain.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. 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

    1997-01-01

    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 learning

  2. Sound localization in callosal agenesis and early callosotomy subjects: brain reorganization and/or compensatory strategies.

    Science.gov (United States)

    Lessard, Nadia; Lepore, Franco; Villemagne, Jean; Lassonde, Maryse

    2002-05-01

    In order to evaluate the callosal involvement in sound localization, the present study examined the response accuracy of acallosal and early callosotomized subjects to monaural and binaural auditory targets presented in three-dimensional space. In these subjects, bilateral localization cues, such as interaural time and level differences, are integrated at the cortical and subcortical levels without the additional support of the callosal commissure. Because acallosal and early-callosotomized subjects have developed with this reduced source of binaural activation of cortical cells, they might have perfected their ability to use monaural sound localization cues. This hypothesis was tested by assessing localization performance under both binaural and monaural listening conditions. Five subjects with callosal agenesis, one callosotomized subject operated early in life and 19 control subjects were asked to localize broad-band noise bursts (BBNBs) of fixed intensity in the horizontal plane in an anechoic chamber. BBNBs were delivered through randomly selected loudspeakers. Two conditions were tested: (i) localization of a stationary sound source; and (ii) localization of a moving sound source. Listeners had to report the apparent stimulus location by pointing to its perceived position on a graduated perimeter. The results indicated that the acallosal subjects were less accurate than controls, but only in the binaural moving sound condition. More interestingly, in the monaural testing conditions, some of the acallosal subjects and the early-callosotomized subject performed significantly better than control subjects. This suggests that, because of the absence of the corpus callosum, these subjects compensate for their reduced access to cortically determined binaural cues by making more efficient use of monaural cues.

  3. Arthrogryposis multiplex congenita with callosal agenesis and dentato-olivary dysplasia.

    Science.gov (United States)

    Saito, Yoshiaki; Hayashi, Masaharu; Miyazono, Yayoi; Shimogama, Tatsuro; Ohno, Kousaku

    2006-05-01

    We report the autopsy case of a boy with arthrogryposis multiplex congenita, associated with callosal agenesis and dentato-olivary dysplasia. The patient manifested with dysmorphic facial features and suffered from intractable epilepsy during the neonatal period. These sets of complications suggest that a common molecular mechanism may be involved in the development of corpus callosum and the folding of the dentate and inferior olivary nuclei. Deep brain structures, including the brainstem and the cerebellum, may be involved in the pathophysiology of symptomatic generalized epilepsy. The differential diagnoses for the clinical and pathological characteristics of this patient are discussed.

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

    Directory of Open Access Journals (Sweden)

    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

  5. Cognitive Modulation of Local and Callosal Neural Interactions in Decision Making

    Directory of Open Access Journals (Sweden)

    Hugo eMerchant

    2014-08-01

    Full Text Available Traditionally, the neurophysiological mechanisms of cognitive processing have been investigated at the single cell level. Here we show that the dynamic, millisecond-by-millisecond, interactions between neuronal events measured by local field potentials are modulated in an orderly fashion by key task variables of a space categorization task performed by monkeys. These interactions were stronger during periods of higher cognitive load and varied in sign (positive, negative. They were observed both within area 7a of the posterior parietal cortex and between symmetric 7a areas of the two hemispheres. Time lags for maximum interactions were longer for opposite- vs. same-hemisphere recordings, and lags for negative interactions were longer than for positive interactions in both recording sites. These findings underscore the involvement of dynamic neuronal interactions in cognitive processing within and across hemispheres. They also provide accurate estimates of lags in callosal interactions, very comparable to similar estimates of callosal conduction delays based on neuroanatomical measurements (Caminiti et al. 2013.

  6. Plasmodesmata without callose and calreticulin in higher plants - open channels for fast symplastic transport?

    Directory of Open Access Journals (Sweden)

    Kirill N. Demchenko

    2014-03-01

    Full Text Available Plasmodesmata (PD represent membrane-lined channels that link adjacent plant cells across the cell wall. PD of higher plants contain a central tube of endoplasmic reticulum called desmotubule. Membrane and lumen proteins seem to be able to move through the desmotubule, but most transport processes through PD occur through the cytoplasmic annulus (Brunkard et al., 2013. Calreticulin (CRT, a highly conserved Ca2+-binding protein found in all multi-cellular eukaryotes, predominantly located in the ER, was shown to localize to PD, though not all PD accumulate CRT. In nitrogen fixing actinorhizal root nodules of the Australian tree Casuarina glauca, the primary walls of infected cells containing the microsymbiont become lignified upon infection. TEM analysis of these nodules showed that during the differentiation of infected cells, PD connecting infected cells, and connecting infected and adjacent uninfected cells, were reduced in number as well as diameter (Schubert et al., 2013. In contrast with PD connecting young infected cells, and most PD connecting mature infected and adjacent uninfected cells, PD connecting mature infected cells did not accumulate CRT. Furthermore, as shown here, these PD were not associated with callose, and based on their diameter, they probably had lost their desmotubules. We speculate that either this is a slow path to PD degradation, or that the loss of callose accumulation and presumably also desmotubules leads to the PD becoming open channels and improves metabolite exchange between cells.

  7. Interhemispheric transfer of kinesthetic information and line bisection task performance in patient with callosal agenesis.

    Science.gov (United States)

    Makashvili, M; Chichinadze, K; Domianidze, T

    2009-09-01

    Patient G.J., male, 7 yrs, with callosal agenesis, was found perfectly able to cross-replicate hand postures in right-to left and left-to-right directions. Bimanual coordination as well as touch localization and intermanual matching were performed without errors. He failed to name 2 out of 8 objects, palpated with the left hand. At the age of 13 patient performed like normal controls in line bisection task, was successful in intermanual replication of hand postures and intermanual matching while failed to name 8 out of 12 familiar objects palpated with the left hand. G.J.'s case does not support idea about bilateral presentation of language centers and development of compensatory ipsilateral afferents in patients with callosal agenesis. Presence of anterior and interictal commissures in G.J. did not contribute to the exchange of information between sensory areas of the right hemisphere and language centers of the left half brain. However, normal intermanual matching and replication of hand postures, as well as high level of line bisection task performance suggests, that anterior and/or intertectal commissure could contribute to the functional integration of sensory areas of the two hemispheres.

  8. Bilateral subcortical heterotopia with partial callosal agenesis in a mouse mutant.

    Science.gov (United States)

    Rosen, G D; Azoulay, N G; Griffin, E G; Newbury, A; Koganti, L; Fujisaki, N; Takahashi, E; Grant, P E; Truong, D T; Fitch, R H; Lu, L; Williams, R W

    2013-04-01

    Cognition and behavior depend on the precise placement and interconnection of complex ensembles of neurons in cerebral cortex. Mutations that disrupt migration of immature neurons from the ventricular zone to the cortical plate have provided major insight into mechanisms of brain development and disease. We have discovered a new and highly penetrant spontaneous mutation that leads to large nodular bilateral subcortical heterotopias with partial callosal agenesis. The mutant phenotype was first detected in a colony of fully inbred BXD29 mice already known to harbor a mutation in Tlr4. Neurons confined to the heterotopias are mainly born in midgestation to late gestation and would normally have migrated into layers 2-4 of overlying neocortex. Callosal cross-sectional area and fiber number are reduced up to 50% compared with coisogenic wildtype BXD29 substrain controls. Mutants have a pronounced and highly selective defect in rapid auditory processing. The segregation pattern of the mutant phenotype is most consistent with a two-locus autosomal recessive model, and selective genotyping definitively rules out the Tlr4 mutation as a cause. The discovery of a novel mutation with strong pleiotropic anatomical and behavioral effects provides an important new resource for dissecting molecular mechanisms and functional consequences of errors of neuronal migration.

  9. 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

    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...

  10. 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.

  11. Intermittent Alien Hand Syndrome and Callosal Apraxia in Multiple Sclerosis: Implications for Interhemispheric Communication

    Science.gov (United States)

    Lunardelli, A.; Sartori, A.; Mengotti, P.; Rumiati, R. I.; Pesavento, V.

    2014-01-01

    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. PMID:24803736

  12. Intermittent alien hand syndrome and callosal apraxia in multiple sclerosis: implications for interhemispheric communication.

    Science.gov (United States)

    Lunardelli, A; Sartori, A; Mengotti, P; Rumiati, R I; Pesavento, V

    2014-01-01

    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.

  13. 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.

    Science.gov (United States)

    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.

  14. Studies on callose and cutin during the expression of competence and determination for organogenic nodule formation from internodes of Humulus lupulus var. Nugget.

    Science.gov (United States)

    Fortes, Ana M; Testillano, Pilar S; Del Carmen Risueño, Maria; Pais, Maria S

    2002-09-01

    Callose and cutin deposition were followed by staining with Aniline Blue and Nile Red and by immunolocalization using antibodies raised against callose. Along with morphogenesis induction from internodes of Humulus lupulus var. Nugget, a temporal and spatial differential deposition of callose and cutin was observed. A cutin layer showing bright yellow autofluorescence appears, surrounding cells or groups of cells committed to express morphogenic competence. This cutin layer that evolves to a randomly organized network appeared underneath a callose layer and may create a specific cellular environment with altered permeability and altered receptors providing conditions for entering the cell cycle. The incipient callose accumulation in control explants cultured on basal medium suggests the involvement of callose in the initiation of the morphogenic programme leading to nodule formation. A scanning electron microscopic study during the organogenic process showed that before shoot bud regeneration, the cutin layer increases in thickness and acquires a smooth texture. This cutin layer is specific to nodular organogenic regions and disappeared with plantlet regeneration. This layer may control permeability to water and solute transfer throughout plantlet regeneration.

  15. The effects of callosal agenesis on the susceptibility to seizures elicited by pentylenetetrazol in BALB/cCF mice.

    Science.gov (United States)

    Medina, Alexandre E; Manhães, Alex C; Schmidt, Sergio L

    2002-01-01

    The effects of callosal agenesis in sensitivity to pentylenetetrazol (PTZ) were studied in 199 (95 males and 104 females) mice of the BALB/cCF strain. This strain presents agenesis of the corpus callosum (CC) in approximately 30% of its population. Seizures were elicited by intraperitoneally injected PTZ. Animals were tested with doses of 40 and 50 mg/kg. Seizure severity was expressed by the following scoring scale: 0 (no abnormal behavior, NAB); 1 (myoclonus, M); 2 (running bouncing clonus, RBC); 3 (tonic hindlimb extension, THE). For the 40-mg/kg dose, abnormal mice were found to be more susceptible, displaying more severe seizures more often then normal mice. Normal female mice were also more susceptible to PTZ than males for this dose. No significant differences were found for the 50-mg/kg dose as a result of the fact that most animals displayed RBC. These data indicate that callosal development and sex are important factors affecting seizure susceptibility.

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

    Science.gov (United States)

    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. Developmental Regulation of the (1,3)-beta-Glucan (Callose) Synthase from Tomato : Possible Role of Endogenous Phospholipases.

    Science.gov (United States)

    Ma, S; Gross, K C; Wasserman, B P

    1991-06-01

    Activity levels of UDP-glucose: (1,3)-beta-glucan (callose) synthase in microsomal membranes of pericarp tissue from tomato fruit (Lycoperisicon esculentum Mill, cv Rutgers) were determined during development and ripening. Addition of the phospholipase inhibitors O-phosphorylcholine and glycerol-1-phosphate to homogenization buffers was necessary to preserve enzyme activity during homogenization and membrane isolation. Enzyme activity declined 90% from the immature green to the red ripe stage. The polypeptide composition of the membranes did not change significantly during ripening. The enzyme from immature fruit was inactivated by exogenously added phospholipases A(2), C, and D. These results suggest that the decline in callose synthase activity during ontogeny may be a secondary effect of endogenous lipase action.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. Why size matters: differences in brain volume account for apparent sex differences in callosal anatomy: the sexual dimorphism of the corpus callosum.

    Science.gov (United States)

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

    2014-01-01

    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 examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Genetic and functional analyses identify DISC1 as a novel callosal agenesis candidate gene.

    Science.gov (United States)

    Osbun, Nathan; Li, Jiang; O'Driscoll, Mary C; Strominger, Zoe; Wakahiro, Mari; Rider, Eric; Bukshpun, Polina; Boland, Elena; Spurrell, Cailyn H; Schackwitz, Wendy; Pennacchio, Len A; Dobyns, William B; Black, Graeme C M; Sherr, Elliott H

    2011-08-01

    Agenesis of the corpus callosum (AgCC) is a congenital brain malformation that occurs in approximately 1:1,000-1:6,000 births. Several syndromes associated with AgCC have been traced to single gene mutations; however, the majority of AgCC causes remain unidentified. We investigated a mother and two children who all shared complete AgCC and a chromosomal deletion at 1q42. We fine mapped this deletion and show that it includes Disrupted-in-Schizophrenia 1 (DISC1), a gene implicated in schizophrenia and other psychiatric disorders. Furthermore, we report a de novo chromosomal deletion at 1q42.13 to q44, which includes DISC1, in another individual with AgCC. We resequenced DISC1 in a cohort of 144 well-characterized AgCC individuals and identified 20 sequence changes, of which 4 are rare potentially pathogenic variants. Two of these variants were undetected in 768 control chromosomes. One of these is a splice site mutation at the 5' boundary of exon 11 that dramatically reduces full-length mRNA expression of DISC1, but not of shorter forms. We investigated the developmental expression of mouse DISC1 and find that it is highly expressed in the embryonic corpus callosum at a critical time for callosal formation. Taken together our results suggest a significant role for DISC1 in corpus callosum development.

  2. Age Differences in Interhemispheric Interactions: Callosal Structure, Physiological Function, and Behavior

    Directory of Open Access Journals (Sweden)

    Brett W Fling

    2011-03-01

    Full Text Available There is a fundamental gap in understanding how brain structural and functional network connectivity are interrelated, how they change with age, and how such changes contribute to older adults’ sensorimotor deficits. Recent neuroimaging approaches including resting state functional connectivity MRI (fcMRI and diffusion tensor imaging (DTI have been used to assess brain functional (fcMRI and structural (DTI network connectivity, allowing for more integrative assessments of distributed neural systems than in the past. Declines in corpus callosum size and microstructure with advancing age have been well documented, but their contributions to age deficits in unimanual and bimanual function are not well defined. Our recent work implicates age-related declines in callosal size and integrity as a key contributor to unimanual and bimanual control deficits. Moreover, our data provide evidence for a fundamental shift in the balance of excitatory and inhibitory interhemispheric processes that occurs with age, resulting in age differences in the relationship between functional and structural network connectivity. Training studies suggest that the balance of interhemispheric interactions can be shifted with experience, making this a viable target for future interventions.

  3. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  5. Arrangement of fiber tracts forming Probst bundle in complete callosal agenesis: report of two cases with an evaluation by diffusion tensor tractography.

    Science.gov (United States)

    Utsunomiya, H; Yamashita, S; Takano, K; Okazaki, M

    2006-12-01

    We report two patients with complete callosal agenesis in whom Probst bundles in both hemispheres could be depicted by diffusion tensor tractography (DTT). While one patient had no associated telencephalic anomaly other than callosal agenesis, the other had cortical dysplasia in the right frontal lobe. Although Probst bundles in the three normal hemispheres were well developed, that in the hemisphere which was affected by cortical dysplasia was small and poorly developed. DTT also showed that the fibers from the frontal pole ran more on the inner side of the Probst bundle than those from a more caudal region of the frontal lobe. Furthermore, fibers from the orbital gyri ran along the outermost side of Probst bundle. The arrangement of these fiber tracts in Probst bundle may reflect the developmental process of callosal fibers in their normal formation.

  6. The Syndrome of Frontonasal Dysplasia, Callosal Agenesis, Basal Encephalocele, and Eye Anomalies – Phenotypic and Aetiological Considerations

    Directory of Open Access Journals (Sweden)

    2004-03-01

    Full Text Available We report ten sporadic cases of Brazilian patients with facial midline defects, callosal agenesis, basal encephalocele, and ocular anomalies. This very rare cluster of anomalies has been well reported before. However, only until recently it is recognized as a syndrome belonging to frontonasal dysplasia spectrum. The ten cases confirm a distinct clinical entity and help to define the phenotype more precisely than previously. Up to now etiology remains unknown, although we conjecture that it is due to a mutation in TGIF gene.

  7. Frontonasal dysplasia, callosal agenesis, basal encephalocele, and eye anomalies syndrome with a partial 21q22.3 deletion.

    Science.gov (United States)

    Guion-Almeida, Maria Leine; Richieri-Costa, Antonio; Jehee, Fernanda Sarquis; Passos-Bueno, Maria Rita Santos; Zechi-Ceide, Roseli Maria

    2012-07-01

    We describe a girl with a phenotype characterized by frontonasal dysplasia, callosal agenesis, basal encephalocele, and eye anomalies who presents a 46,XX,r(21) karyotype. Array-comparative genomic hybridization using the Afflymetrix 100K DNA oligoarray set showed an interstitial deletion 21q22.3 of approximately 219 kb. Conventional karyotype of both parents was normal, and it was not possible to perform the molecular studies. In this report we raise the hypothesis that the deleted genes located at 21q22.3 could account to the phenotype.

  8. Periventricular nodular heterotopia, frontonasal encephalocele, corpus callosal dysgenesis and arachnoid cyst: A constellation of abnormalities in a child with epilepsy.

    Science.gov (United States)

    Krishnan, Prasad; Chattopadhyay, Arijit; Saha, Manash

    2014-01-01

    A 7-year-old male child presented with poorly controlled generalized tonic-clonic seizures. On examination, he was mentally retarded, deaf and had a swelling at the root on the nose. Computed tomography scan done previously revealed a left temporal arachnoid cyst (AC) due to which he was referred for surgery. However, magnetic resonance imaging revealed a constellation of abnormalities - all of which could be responsible for his seizures. The combination of periventricular nodular heterotopias with encepaholcele is rarely described in the literature, and more infrequently so its combination with AC and callosal dysgenesis - the Chudley-Mccullough syndrome. We describe the case and review relevant literature on this subject.

  9. The effects of age, memory performance, and callosal integrity on the neural correlates of successful associative encoding.

    Science.gov (United States)

    de Chastelaine, Marianne; Wang, Tracy H; Minton, Brian; Muftuler, L Tugan; Rugg, Michael D

    2011-09-01

    This functional magnetic resonance imaging study investigated the relationship between the neural correlates of associative memory encoding, callosal integrity, and memory performance in older adults. Thirty-six older and 18 young subjects were scanned while making relational judgments on word pairs. Neural correlates of successful encoding (subsequent memory effects) were identified by contrasting the activity elicited by study pairs that were correctly identified as having been studied together with the activity elicited by pairs wrongly judged to have come from different study trials. Subsequent memory effects common to the 2 age groups were identified in several regions, including left inferior frontal gyrus and bilateral hippocampus. Negative effects (greater activity for forgotten than for remembered items) in default network regions in young subjects were reversed in the older group, and the amount of reversal correlated negatively with memory performance. Additionally, older subjects' subsequent memory effects in right frontal cortex correlated positively with anterior callosal integrity and negatively with memory performance. It is suggested that recruitment of right frontal cortex during verbal memory encoding may reflect the engagement of processes that compensate only partially for age-related neural degradation.

  10. Longitudinal study of callosal microstructure in the normal adult aging brain using quantitative DTI fiber tracking.

    Science.gov (United States)

    Sullivan, Edith V; Rohlfing, Torsten; Pfefferbaum, Adolf

    2010-01-01

    We present a review of neuroimaging studies of normal adult aging conducted with diffusion tensor imaging (DTI) and data from one of the first longitudinal studies using DTI to study normal aging. To date, virtually all DTI studies of normal adult aging have been cross-sectional and have identified several patterns of white matter microstructural sparing and compromise that differentiate regional effects, fiber type, and diffusivity characteristics: (1) fractional anisotropy (FA) is lower and mean diffusivity is higher in older than younger adults, (2) aging is characterized by an anterior-to-posterior gradient of greater-to-lesser compromise also seen in superior-to-inferior fiber systems, and (3) association fibers connecting cortical sites appear to be more vulnerable to aging than projection fibers. The results of this longitudinal study of the macrostructure and microstructure of the corpus callosum yielded a consistent pattern of differences between healthy, young (20s to 30s) and elderly (60s to 70s) men and women without change over 2 years. We then divided the fibers of the corpus callosum into the midsagittal strip and the lateral distal fibers in an attempt to identify the locus of the age-related differences. The results indicated that, on average, mean values of FA and longitudinal diffusivity (lambdaL) were lower in the distal than midsagittal fibers in both groups, but the age effects and the anterior-to-posterior gradients were more pronounced for the distal than midsagittal fibers and extended more posteriorly in the distal than midsagittal fibers. Despite lack of evidence for callosal aging over 2 years, ventricular enlargement occurred and was disproportionately greater in the elderly relative to the young group, being 8.2% in the elderly but only 1.2% in the young group. Thus, different brain regions can express different rates of change with aging. Our longitudinal DTI data indicate that normal aging is associated with declining FA and

  11. Periventricular nodular heterotopia, frontonasal encephalocele, corpus callosal dysgenesis and arachnoid cyst: A constellation of abnormalities in a child with epilepsy

    Directory of Open Access Journals (Sweden)

    Prasad Krishnan

    2014-01-01

    Full Text Available A 7-year-old male child presented with poorly controlled generalized tonic-clonic seizures. On examination, he was mentally retarded, deaf and had a swelling at the root on the nose. Computed tomography scan done previously revealed a left temporal arachnoid cyst (AC due to which he was referred for surgery. However, magnetic resonance imaging revealed a constellation of abnormalities - all of which could be responsible for his seizures. The combination of periventricular nodular heterotopias with encepaholcele is rarely described in the literature, and more infrequently so its combination with AC and callosal dysgenesis - the Chudley-Mccullough syndrome. We describe the case and review relevant literature on this subject.

  12. Fetal development of the corpus callosum: Insights from a 3T DTI and tractography study in a patient with segmental callosal agenesis.

    Science.gov (United States)

    Scola, Elisa; Sirgiovanni, Ida; Avignone, Sabrina; Cinnante, Claudia Maria; Biffi, Riccardo; Fumagalli, Monica; Triulzi, Fabio

    2016-10-01

    Commissural embryology mechanisms are not yet completely understood. The study and comprehension of callosal dysgenesis can provide remarkable insights into embryonic or fetal commissural development. The diffusion tensor imaging (DTI) technique allows the in vivo analyses of the white-matter microstructure and is a valid tool to clarify the disturbances of brain connections in patients with dysgenesis of the corpus callosum (CC). The segmental callosal agenesis (SCAG) is a rare partial agenesis of the corpus callosum (ACC). In a newborn with SCAG the DTI and tractography analyses proved that the CC was made of two separate segments consisting respectively of the ventral part in the genu and body of the CC, connecting the frontal lobes, and the dorsal part in the CC splenium and the attached hippocampal commissure (HC), connecting the parietal lobes and the fornix. These findings support the embryological thesis of a separated origin of the ventral and the dorsal parts of the CC.

  13. Chronic stress alters the dendritic morphology of callosal neurons and the acute glutamate stress response in the rat medial prefrontal cortex.

    Science.gov (United States)

    Luczynski, Pauline; Moquin, Luc; Gratton, Alain

    2015-01-01

    We have previously reported that interhemispheric regulation of medial prefrontal cortex (PFC)-mediated stress responses is subserved by glutamate (GLU)- containing callosal neurons. Evidence of chronic stress-induced dendritic and spine atrophy among PFC pyramidal neurons led us to examine how chronic restraint stress (CRS) might alter the apical dendritic morphology of callosal neurons and the acute GLU stress responses in the left versus right PFC. Morphometric analyses of retrogradely labeled, dye-filled PFC callosal neurons revealed hemisphere-specific CRS-induced dendritic retraction; whereas significant dendritic atrophy occurred primarily within the distal arbor of left PFC neurons, it was observed within both the proximal and distal arbor of right PFC neurons. Overall, CRS also significantly reduced spine densities in both hemispheres with the greatest loss occurring among left PFC neurons, mostly at the distal extent of the arbor. While much of the overall decrease in dendritic spine density was accounted by the loss of thin spines, the density of mushroom-shaped spines, despite being fewer in number, was halved. Using microdialysis we found that, compared to controls, basal PFC GLU levels were significantly reduced in both hemispheres of CRS animals and that their GLU response to 30 min of tail-pinch stress was significantly prolonged in the left, but not the right PFC. Together, these findings show that a history of chronic stress alters the dendritic morphology and spine density of PFC callosal neurons and suggest a mechanism by which this might disrupt the interhemispheric regulation of PFC-mediated responses to subsequent stressors.

  14. Synergistic activation of defense responses in Arabidopsis by simultaneous loss of the GSL5 callose synthase and the EDR1 protein kinase.

    Science.gov (United States)

    Wawrzynska, Anna; Rodibaugh, Natalie L; Innes, Roger W

    2010-05-01

    Loss-of-function mutations in the EDR1 gene of Arabidopsis confer enhanced resistance to Golovinomyces cichoracearum (powdery mildew). Disease resistance mediated by the edr1 mutation is dependent on an intact salicylic acid (SA) signaling pathway, but edr1 mutant plants do not constitutively express the SA-inducible gene PR-1 and are not dwarfed. To identify other components of the EDR1 signaling network, we screened for mutations that enhanced the edr1 mutant phenotype. Here, we describe an enhancer of edr1 mutant, eed3, which forms spontaneous lesions in the absence of pathogen infection, constitutively expresses both SA- and methyl jasmonate (JA)-inducible defense genes, and is dwarfed. Positional cloning of eed3 revealed that the mutation causes a premature stop codon in GLUCAN SYNTHASE-LIKE 5 (GSL5, also known as POWDERY MILDEW RESISTANT 4), which encodes a callose synthase required for pathogen-induced callose production. Significantly, gsl5 single mutants do not constitutively express PR-1 or AtERF1 (a JA-inducible gene) and are not dwarfed. Thus, loss of both EDR1 and GSL5 function has a synergistic effect. Our data suggest that EDR1 and GSL5 negatively regulate SA and JA production or signaling by independent mechanisms and that negative regulation of defense signaling by GSL5 may be independent of callose production.

  15. 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.)

  16. Connectivity and the corpus callosum in autism spectrum conditions: insights from comparison of autism and callosal agenesis.

    Science.gov (United States)

    Booth, Rhonda; Wallace, Gregory L; Happé, Francesca

    2011-01-01

    Neural models of autism spectrum disorders (ASDs) have moved, in recent years, from a lesion model to a focus on abnormal connectivity. In this chapter, we review this work and summarize findings from our recent research comparing autism and agenesis of the corpus callosum (AgCC). We discuss our findings in the context of the "fractionable triad" account and highlight three main points. First, the social aspects of autism can be found in isolation, not accompanied by the nonsocial features of this disorder, supporting a view of autism as a "compound," rather than "monolithic," condition. Second, many young people with callosal agenesis show theory of mind- and emotion-processing deficits akin to those seen in autism. Diagnostic overshadowing may mean these people do not receive interventions that have proven beneficial in ASD. Last, study of AgCC shows that it is possible, in some cases, to develop good social cognitive skills in the absence of the corpus callosum, presenting a challenge to future connectivity models of autism.

  17. Effects of callosal agenesis on rotational side preference of BALB/cCF mice in the free swimming test.

    Science.gov (United States)

    Filgueiras, Cláudio C; Manhães, Alex C

    2004-11-05

    In order to test the hypothesis that the ontogenetic development of the corpus callosum is related to the establishment of behavioral laterality, the rotatory behavior in the free swimming test was studied in male mice of the BALB/cCF strain, in which approximately 20% of the animals present total or partial callosal agenesis. All animals were submitted to three sessions of the free-swimming rotatory test in three different sessions (diameter of the recipient = 21 cm; session duration = 5 min; inter-test interval = 48 h). The number and direction of the 30 and 360 degrees turns were recorded. Animals were classified as side-consistent turners (to the right or to the left) when they did not change their preferred side of rotation in all three sessions and in both turning units. In general our results suggested that acallosal animals present more pronounced laterality than normal ones. In the acallosal group, the percentage of consistent turners was significantly higher than that of non-consistent turners. The percentage of animals that presented strong turning preferences in the acallosal group was higher than in the normal group. In first session, the acallosal group presented a higher average number of turns to preferred side than the normal group. Taken together, our results constitute an endorsement to the hypothesis that the normal development of the corpus callosum is related to the establishment of cerebral laterality.

  18. Delineation of a deletion region critical for corpus callosal abnormalities in chromosome 1q43-q44.

    Science.gov (United States)

    Nagamani, Sandesh C Sreenath; Erez, Ayelet; Bay, Carolyn; Pettigrew, Anjana; Lalani, Seema R; Herman, Kristin; Graham, Brett H; Nowaczyk, Malgorzata Jm; Proud, Monica; Craigen, William J; Hopkins, Bobbi; Kozel, Beth; Plunkett, Katie; Hixson, Patricia; Stankiewicz, Pawel; Patel, Ankita; Cheung, Sau Wai

    2012-02-01

    Submicroscopic deletions involving chromosome 1q43-q44 result in cognitive impairment, microcephaly, growth restriction, dysmorphic features, and variable involvement of other organ systems. A consistently observed feature in patients with this deletion are the corpus callosal abnormalities (CCAs), ranging from thinning and hypoplasia to complete agenesis. Previous studies attempting to delineate the critical region for CCAs have yielded inconsistent results. We conducted a detailed clinical and molecular characterization of seven patients with deletions of chromosome 1q43-q44. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. Four patients had CCAs, and shared the smallest region of overlap that contains only three protein coding genes, CEP170, SDCCAG8, and ZNF238. One patient with a small deletion involving SDCCAG8 and AKT3, and another patient with an intragenic deletion of AKT3 did not have any CCA, implying that the loss of these two genes is unlikely to be the cause of CCA. CEP170 is expressed extensively in the brain, and encodes for a protein that is a component of the centrosomal complex. ZNF238 is involved in control of neuronal progenitor cells and survival of cortical neurons. Our results rule out the involvement of AKT3, and implicate CEP170 and/or ZNF238 as novel genes causative for CCA in patients with a terminal 1q deletion.

  19. Abnormal Changes of Callose Distribution During Pollen Abortion in Populus tomentosa Carr.%毛白杨花粉败育过程中胼胝质的异常分布变化

    Institute of Scientific and Technical Information of China (English)

    张文超; 曹媛; 常童洁; 荆艳萍

    2013-01-01

    The callose deposition in the process of microsporogenesis of Populus tomentosa Carr.male fertile clone 1319 and sterile stub BM-1 was investigated by staining with aniline blue.In fertile anthers,callose deposition occurs at the corners of the microspore mother cells,and then at the dyad and tetrad stage a thick callose wall locates in the cells plate and cells surrounding.With the dissolution of the callose wall,microspores are released into the chamber,and there is little callose around the free microspores.At the mature pollen stage,with tapetum disintegration,endothecium thickning and chamber cracking,callose distributes in the residual tapetum and endothecium.Compared with its counterpart,callose synthesis in BM-1 anthers decreases and callose distribution shows obvious abnormality.No callose appeares in sterile anther during the microspore mother cell period.At the dyad and tetrad stage,callose mainly deposits in the cells plate but less around the dyads and tetrads.With the development of the microspore to mature pollen,the callose deposits in the tapetum significantly,but not in the endothecium.Ultrastructural observation with transmission electron microscopy showed normal development in 1319 and abnormal development in BM-1 pollens.Therefore,the abnormal synthesis and distribution of callose is one of the reasons for pollen abortion of P.tomentosa Carr.%采用苯胺蓝染色的方法,对育性良好的无性系1319及花粉败育雄株BM-1的花药发育过程中胼胝质的分布及变化进行了观察.结果表明,育性良好的花药中,胼胝质首先在小孢子母细胞角隅处沉积;随后,较厚的胼胝质壁分布于四分体细胞间以及细胞周围,随着胼胝质的解体,小孢子释放到药室中,游离小孢子外围无明显胼胝质分布;小孢子发育形成成熟花粉,花药绒毡层解体,内壁加厚开裂,胼胝质分布于残留的绒毡层以及内壁.与育性良好的花药相比,败育花药的胼胝质合成量减

  20. 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.

  1. A mammalian conserved element derived from SINE displays enhancer properties recapitulating Satb2 expression in early-born callosal projection neurons.

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    Kensuke Tashiro

    Full Text Available Short interspersed repetitive elements (SINEs are highly repeated sequences that account for a significant proportion of many eukaryotic genomes and are usually considered "junk DNA". However, we previously discovered that many AmnSINE1 loci are evolutionarily conserved across mammalian genomes, suggesting that they may have acquired significant functions involved in controlling mammalian-specific traits. Notably, we identified the AS021 SINE locus, located 390 kbp upstream of Satb2. Using transgenic mice, we showed that this SINE displays specific enhancer activity in the developing cerebral cortex. The transcription factor Satb2 is expressed by cortical neurons extending axons through the corpus callosum and is a determinant of callosal versus subcortical projection. Mouse mutants reveal a crucial function for Sabt2 in corpus callosum formation. In this study, we compared the enhancer activity of the AS021 locus with Satb2 expression during telencephalic development in the mouse. First, we showed that the AS021 enhancer is specifically activated in early-born Satb2(+ neurons. Second, we demonstrated that the activity of the AS021 enhancer recapitulates the expression of Satb2 at later embryonic and postnatal stages in deep-layer but not superficial-layer neurons, suggesting the possibility that the expression of Satb2 in these two subpopulations of cortical neurons is under genetically distinct transcriptional control. Third, we showed that the AS021 enhancer is activated in neurons projecting through the corpus callosum, as described for Satb2(+ neurons. Notably, AS021 drives specific expression in axons crossing through the ventral (TAG1(-/NPY(+ portion of the corpus callosum, confirming that it is active in a subpopulation of callosal neurons. These data suggest that exaptation of the AS021 SINE locus might be involved in enhancement of Satb2 expression, leading to the establishment of interhemispheric communication via the corpus callosum

  2. 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

  3. Callose Fluorescence Labeling in the Different Soybean Varieties Resistant to Soybean Mosaic Virus%大豆不同花叶病毒抗性品种胼胝质荧光标记初探

    Institute of Scientific and Technical Information of China (English)

    吴思思; 李文龙; 肖东强; 侯春燕; 王冬梅

    2013-01-01

    选用6个大豆品种与4个不同的大豆花叶病毒株系,分别组成抗病级别不同的组合,通过对接种叶片与上位叶症状观察、苯胺蓝染色辅以荧光显微镜观察和药物学试验,探讨了不同抗病级别组合中胼胝质(即β-1,3-葡聚糖)积累的特点及其在大豆抵抗大豆花叶病毒侵染过程中的作用.试验结果表明,大豆接种病毒后,在抗病级别分别为0~3的各个组合的叶肉细胞中,在侵染早期(接种后6、72 h)不同的组合在不同时间点分别观察到了胼胝质荧光,且胼胝质荧光出现的时间与抗病级别密切相关,即抗病性越强的组合在侵染点处观察到胼胝质的时间越早;而在抗病级别为5的组合中一直未能观察到胼胝质荧光.另外,在抗病级别为0级和1级的各组合中给叶片预注射2-DDG(2-deoxy-D-glucose,一种胼胝质合成抑制剂)再接种病毒,在上位叶能观察到坏死斑的出现并且通过RT-PCR能够检测到大豆花叶病毒外壳蛋白基因.以上结果表明,大豆被大豆花叶病毒侵染后,抗病性越强的品种就会在侵染点处越早地积累胼胝质,胼胝质的沉积与大豆抗病毒侵染密切相关.%The selected six varieties of soybean and four different strains of soybean mosaic virus ( SMV ) are divided into nine combinations that respond to different resistance levels. Through the symptom observation of inoculated leaves and the upper leaves, aniline blue staining followed by fluorescence microscopy, and pharmacological experiment, we wanted to study the characteristics of callose( β-1 ,3-glucan) accumulation in combinations of different resistance levels and the function of callose in the process of soybean and SMV interaction. The results showed that, in the earlier period of time after inoculation (6-72 h) , callose fluorescence in the mesophyll cells of different combinations , which resistance levels ranges from 0 to 3 , were observed at different time depending on

  4. [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.

  5. Callosal Agenesis and Interhemispheric Cysts

    OpenAIRE

    J Gordon Millichap

    2001-01-01

    Imaging studies of 25 cases of agenesis of the corpus callosum with interhemispheric cyst were retrospectively reviewed at the University of California, San Francisco, and Harvard Medical School, Boston.

  6. Unitary attention in callosal agenesis.

    Science.gov (United States)

    Dell'acqua, R; Jolicoeur, P; Lassonde, M; Angrilli, A; De Bastiani, P; Pascali, A

    2005-01-01

    The interhemispheric organisation of two specific components of attention was investigated in three patients affected by partial or complete agenesis of the corpus callosum. A visuospatial component of attention was explored using a visual search paradigm in which target and distractors were displayed either unilaterally within a single visual hemifield, or bilaterally across both visual hemifields in light of prior work indicating that split-brain patients were twice as fast to scan bilateral displays compared to unilateral displays. A central component of attention was explored using a psychological refractory period (PRP) paradigm in which two visual stimuli were presented laterally at various stimulus onset asynchronies (SOAs), with each stimulus associated with a different speeded two-alternative choice task. The stimulus-response compatibility in the second task was systematically manipulated in this paradigm, in light of prior work indicating that split-brain patients exhibited a close-to-normal PRP effect (i.e., slowing of the second response as SOA is decreased), with, however, abnormally decreasing effects of the manipulation of the response mapping on the second task speed as SOA was decreased. The present results showed that, although generally slower than normals in carrying out the two tasks, the performance of each of the three acallosal patients was formally equivalent to the performance of a matched control group of normal individuals. In the visual search task, the search rate of the acallosal patients was the same for unilateral and bilateral displays. Furthermore, in the PRP task, there was more mutual interference between the lateralised tasks for the acallosal patients than that evidenced in the performance of the matched control group. It is concluded that the visuospatial component and the central component of attention in agenesis of the corpus callosum are interhemispherically integrated systems.

  7. Indirect ultrasonic signs of the callosal partial agenesis and hypoplasia in the fetus%胎儿胼胝体部分性缺失及发育不良横切面特征声像分析

    Institute of Scientific and Technical Information of China (English)

    蔡丹蕾; 李丽娟; 汪南; 吴丽红; 杜柳; 谢红宁

    2014-01-01

    目的:总结胼胝体部分性缺失及发育不良胎儿产前二维超声常规横切面特征声像,为产前超声诊断部分性胼胝体缺失提供线索。方法:回顾性分析本院2006年至今经MRI或大体病理确诊的单纯性胼胝体部分性缺失病例产前常规二维横切面声像图中透明隔间腔缺失、侧脑室异常及第三脑室上抬发生率,追踪预后及染色体结果。结果:经MRI或大体病理证实单纯性胼胝体部分性缺失病例10例。9例为部分性胼胝体缺失,1例为胼胝体发育不良。透明隔间腔缺失率20%,侧脑室异常发生率60%,第三脑室上抬发生率80%。8例终止妊娠,2例出生:1例随访至2岁,生长发育无异常;1例3岁,随访至今,生长发育均落后于同龄儿童。6例行染色体检查,结果均正常。结论:以二维超声横切面间接征象作为胼胝体部分性缺失的产前诊断线索是可行的。胼胝体部分性缺失胎儿特征声像发生率与完全性胼胝体缺失胎儿不同,其侧脑室及第三脑室异常发生率较透明隔间腔缺失率高。单纯性胼胝体部分性缺失胎儿染色体结果正常,预后未知。%Objective To investigate antenatal sonographic findings of the fetal isolated callosal hypoplasia and partial agenesis. Methods A retrospective study was performed on the cases of hypoplasia and partial agenesis of the corpus callosum suspected at antenatal sonographic basic examination from 2006 to 2014, all the cases were confirmed by pathology or magnetic resonance imaging(MRI). For the surviving infants, clinical follow-up had been performed to assess the developmental outcome. Results Thirteen fetuses suspected with callosal underdevelopment were identified at a median gestational age of 31 (range, 18~39) weeks. Ten cases were confirmed by autopsy and MRI, including 9 with partial agenesis and 1 with hypoplasia. Among the 10 fetuses confirmed with isolated partial

  8. 神经内镜下经纵裂胼胝体侧脑室入路的应用解剖%Lateral ventricular neuroendoscopic anatomy through the interhemispheric transcorpus callosal approach

    Institute of Scientific and Technical Information of China (English)

    吴春富; 陆华

    2011-01-01

    Objective To provide anatomical basis for lateral ventricular neuroendoscopic surgery through the interhemispheric transcorpus callosal approach. Methods The anatomic investigation of the lateral and third ventricle was performed in 10 adult cadaveric head specimens, through interhemispheric transcorpus callosal approach. Results The thickness of corpus callosum was (6.1±1.2) mm, the sagittal and transverse diameters of interventricular foreman (5.6±1.4) mm and (3.0±1.6) mm, and the sagittal and transverse diameters ofinterthalamic adhesion (6.3±1.8) mm and (3.4±1.2) mm. There were very less drainage veins to the sagittal sinus anterior to the coronal suture. The body and front horn of the lateral ventricle, the "Y" shape structure of interventricular foreman could be observed under different angular neuroendoscope. Cut size of 2 cm on corpus callosum than that of 1.5 cm was better to reveal the structures and exert operation under a rigid endoscopic surgery. Conclusions Interhemispheric transcorpus callosal approach is a safe and valuable way to treat affection in double lateral ventricle, area of interventricular foreman and the third ventricle.%目的 为临床开展神经内镜下经纵裂胼胝体侧脑室入路到达侧脑室及第三脑室手术提供应用解剖学基础.方法 对10例成人尸头标本经纵裂胼胝体前部侧脑室入路在神经内镜下观察侧脑室、第三脑室结构并测量数据.结果 (1)胼胝体厚度(6.1±1.2)mm,室间孔长、宽径为(5,6±1.4)mm、(3.0±1.6)mm,中间块长、宽径(6.3±1.8)mm、(3.4±1.2)mm;(2)冠状缝前5cm引流静脉很少;(3)神经内镜观察侧脑室前角、侧脑室体部及室间孔的Y形结构,且可以通过室间孔进入第三脑室,进行较好的暴露和观察;(4)胼胝体切开1.5 cm,硬质内镜操作空间和观察范围受限,胼胝体切开2.0 cm时,适合神经内镜操作和观察.结论 经纵裂胼胝体前部侧脑室入路按生理间隙进入,操作距离短,内镜

  9. Study on the distribution of callose and β-1,3-D-glucanase in Chenopodium quinoa by immuno-gold labeling%免疫胶体金标记定位昆诺藜中的胼胝质和胼胝质降解酶

    Institute of Scientific and Technical Information of China (English)

    李云琴; 王华; 谢礼; 洪健

    2014-01-01

    运用免疫胶体金技术研究了感染蚕豆萎蔫病毒2号以及健康昆诺藜细胞中胼胝质和胼胝质降解酶的分布情况。电镜观察发现胶体金特异性标记在含有VP37小管的胞间运动通道周围,其余区域感病和健康细胞的胼胝质及胼胝质降解酶分布差别不大,胼胝质主要分布于细胞间隙的大块电子致密物质以及细胞壁结构发生较大变化的区域,胼胝质降解酶主要分布于筛板、维管束细胞紧贴细胞壁区域的大块电子致密物质上,在细胞壁结构发生较大改变的区域也有胼胝质降解酶的分布。推测胼胝质在昆诺藜细胞中的积累和降解可能与细胞壁结构成分改变有关。%The distribution of callose and β⁃1,3⁃D⁃glucanase in the Broad bean wilt virus 2 ( BBWV 2 ) infected and the healthy Chenopodium quinoa was investigated by using immuno⁃gold labeling with the antibody against callose and β⁃1, 3⁃D⁃glucanase, respectively. The results show that, except for the VP37 intercellular moving cell wall pathways, there is no obvious difference on the distribution of callose and β⁃1,3⁃D⁃glucanase between the infected and healthy cells. Callose is mainly distributed on the regions as bellow:the electron condensed material which located in the intercellular space, the structural altered region of cell wall and the cell wall broken region. Glucanase is mainly distributed on the regions as bellow:the sieve plate, the electron condensed material attached to cell wall in the vascular bundle and the structural altered region of cell wall. From these results, it can be deduced that the accumulation and degradation of callose in C. quinoa is related to the cell wall structural and component alteration.

  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

    Directory of Open Access Journals (Sweden)

    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. Clinical Correlates of Corpus Callosal Agenesis

    OpenAIRE

    J Gordon Millichap

    1998-01-01

    The clinical correlates of agenesis of the corpus callosum were examined in 56 cases (37 adult, 19 pediatric) reported to the British Neurological Surveillance Unit (BNSU) and surveyed at the Department of Psychological Medicine, Institute of Psychiatry, London, UK.

  13. Callosal agenesis and Open lip Schizencephaly.

    Science.gov (United States)

    Prasad, Maya; Iype, Mary; Nair, P M C

    2006-09-01

    We report a case of a new born who presented with neonatal seizures; and who had coexistence of a Corpus Callosum Agenesis with a bilateral Open lip Schizencephaly and a Dandy Walker malformation. The investigations for an underlying etiology, however was futile.

  14. 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.

  15. 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.

  16. Language and Development in FG Syndrome with Callosal Agenesis.

    Science.gov (United States)

    McCardle, Peggy; Wilson, Bruce

    1993-01-01

    The FG syndrome is characterized by unusual facies; sudden infant death; developmental delay; and abnormalities of the cardiac, gastrointestinal, and central nervous systems. Serial evaluations of one case with isolated agenesis of the corpus callosum found consistent patterns over time in specific language impairments in syntactic and…

  17. Callosal agenesis, chorioretinal lacunae, absence of infantile spasms, and normal development: Aicardi syndrome without epilepsy?

    Science.gov (United States)

    Prats Viñas, Jose Maria; Martinez Gonzalez, María Jesús; Garcia Ribes, Ainhoa; Martinez Gonzalez, Sonia; Martinez Fernandez, Ricardo

    2005-06-01

    Aicardi syndrome is defined by the clinical triad of infantile spasms, agenesis of the corpus callosum, and pathognomonic chorioretinal lacunae. Almost all patients are females with severe cognitive and physical disabilities. All of the cases reported in the literature have had early-onset seizures. Most cases of Aicardi syndrome exhibit very slow development, even when seizures are eventually controlled, and the cases with a relatively favourable outcome are associated with low intelligence quotient levels. A relationship between chorioretinal changes or severity of the agenesis of the corpus callosum and prognosis of Aicardi syndrome has been claimed, but few data are available about the clinical features that can predict clinical outcome. We describe a case of Aicardi syndrome in a female aged 24 months. Magnetic resonance imaging showed complete agenesis of the corpus callosum and ophthalmoscopy revealed chorioretinal lacunae in the left eye. She had never had seizures and her psychomotor and language development were normal for age.

  18. Interhemispheric Connections between the Primary Visual Cortical Areas via the Anterior Commissure in Human Callosal Agenesis

    OpenAIRE

    van Meer, Nathalie; Houtman, Anne C.; Van Schuerbeek, Peter; Vanderhasselt, Tim; Milleret, Chantal; ten Tusscher, Marcel P.

    2016-01-01

    Aim: In humans, images in the median plane of the head either fall on both nasal hemi-retinas or on both temporal hemi-retinas. Interhemispheric connections allow cortical cells to have receptive fields on opposite sides. The major interhemispheric connection, the corpus callosum, is implicated in central stereopsis and disparity detection in front of the fixation plane. Yet individuals with agenesis of the corpus callosum may show normal stereopsis and disparity vergence. We set out to study...

  19. Callosal agenesis: case report%单纯胼胝体缺如1例

    Institute of Scientific and Technical Information of China (English)

    赵永华; 吴新淮

    2005-01-01

    患者女,18岁,发现智力低下6年,伴视力逐渐下降。MRI显示:矢状位的T1加权像胼胝体未显示,大脑半球内侧面的脑沟随上移的第三脑室顶部呈放射状排列,小脑扁桃体位置下移,平枕骨大孔水平(图1),在横断面图像上见侧脑室枕角扩大而额角变小,

  20. 胼胝体发育不全的MRI诊断%MRI diagnosis of callosal agenesis

    Institute of Scientific and Technical Information of China (English)

    王晓明; 万玉珍; 朱丽艳; 焦鑫明; 李玉龙

    2004-01-01

    目的探讨MRI对胼胝体发育不全的诊断价值.方法回顾性分析12例胼胝体发育不全的临床及MRI表现,并结合文献加以讨论.结果MRI显示6例胼胝体完全阙如,4例部分阙如,2例变薄.结论MRI可以直接观察胼胝体形态,是诊断胼胝体发育不全的首选方法.

  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. Language Lateralization in Individuals with Callosal Agenesis: An fMRI Study

    Science.gov (United States)

    Pelletier, Isabelle; Paquette, Natacha; Lepore, Franco; Rouleau, Isabelle; Sauerwein, Catherine H.; Rosa, Christine; Leroux, Jean-Maxime; Gravel, Pierre; Valois, Katja; Andermann, Frederick; Saint-Amour, Dave; Lassonde, Maryse

    2011-01-01

    Since the seminal work of Broca in 1861, it is well established that language is essentially processed in the left hemisphere. However, the origin of hemispheric specialization remains controversial. Some authors posit that language lateralization is genetically determined, while others have suggested that hemispheric specialization develops with…

  3. [A case of diagnostic dyspraxia without ideomotor apraxia by callosal lesion].

    Science.gov (United States)

    Tei, H; Soma, Y; Uchiyama, S; Maruyama, S

    1993-05-01

    A case of diagnostic dyspraxia was reported. A 57-year-old right handed male had been suffering from the lack of cooperation between his right and left hands for six months. Except for decreased deep tendon reflexes in all extremities, there were no abnormal findings on neurological examination. On neuropsychological examination, he was attentive, well orientated and his spontaneous speech, comprehension, naming, repetition and reading were intact. There was peculiar dissociative behavior between his right and left hands. For instance, he put a cigarette or coin in the pocket with his right hand then his left hand took out and replaced them, and he buttoned his shirts with his right hand but then unbuttoned with his left hand. These left hand oppositional behavior to his right hand were triggered by voluntary activities of his right hand. Left unilateral agraphia was also revealed but ideomotor apraxia, compulsive manipulation of tools and grasp reflex were not demonstrated. T1-weighted MRI demonstrated irregular low signal intensity areas extending from the genu to the body of the corpus callosum. No definite lesion was detected in the medial aspect of the frontal lobe. Only small numbers of diagnostic dyspraxia have been reported and such cases without ideomotor apraxia or medial frontal lesion are even rare. MRI is very useful for detecting the lesion of the corpus callosum.

  4. 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.

  5. Balancing bilateral sensory activity: callosal processing modulates sensory transmission through the contralateral thalamus by altering the response threshold.

    Science.gov (United States)

    Li, Lu; Ebner, Ford F

    2006-07-01

    Rats tactually explore a nearly spherical space field around their heads with their whiskers. The information sampled by the two sets of whiskers is integrated bilaterally at the cortical level in an activity dependent manner via the corpus callosum. We have recently shown that sensory activity in one barrel field cortex (BFC) modulates the processing of incoming sensory information to the other BFC. Whether interhemispheric integration is dynamically linked with corticothalamic modulation of incoming sensory activity is an important hypothesis to test, since subcortical relay neurons are directly modulated by cortical neurons through top-down processes. In the present study, we compared the direct sensory responses of single thalamic relay neurons under urethane anesthesia before and after inactivating the BFC contralateral to a thalamic neuron. The data show that silencing one BFC reduces response magnitude in contralateral thalamic relay neurons, significantly and reversibly, in response to test stimuli applied to the principal whisker at two times response threshold (2T) intensity for each unit. Neurons in the ventral posterior medial (VPM) nucleus and the medial division of the posterior nucleus (POm) react in a similar manner, although POm neurons are more profoundly depressed by inactivation of the contralateral BFC than VPM neurons. The results support the novel idea that the subcortical relay of sensory information to one hemisphere is strongly modulated by activity levels in the contralateral as well as in the ipsilateral SI cortex. The mechanism of the modulation appears to be based on shifting the stimulus-response curves of thalamic neurons, thereby rendering them more or less sensitive to sensory stimuli. We conclude that global sensory processing is created by combining activity in each cerebral hemisphere and continually balancing the flow of information to cortex by adjusting the responsiveness of ascending sensory pathways.

  6. Callosal agenesis affects consistency of laterality in a paw preference task in BALB/cCF mice.

    Science.gov (United States)

    Manhães, Alex C; Schmidt, Sergio L; Filgueiras, Cláudio C

    2005-04-15

    We tested the hypothesis that the ontogenetic development of the corpus callosum (CC) affects the consistency of laterality in a paw preference task. Adult male mice (55 normal and 29 acallosal) of the BALB/cCF strain were initially tested (twice; inter-test interval: 72 h) in an unbiased setup in which both forepaws could easily perform a reaching movement. In a subsequent test, animals were placed in a biased setup that favored the use of the non-preferred paw. Acallosal and normal mice were strongly lateralized in the unbiased setup. Additionally, while normal mice did not present a populational bias favoring one of the paws, acallosal mice presented a significant bias favoring the left paw. In the biased setup, left- and right-pawed normal mice were equally consistent (approximately 65% of the animals, in both groups, used the preferred paw of the initial two tests, in spite of the bias). Conversely, while left-pawed acallosal mice were as consistent (65%) as normal mice, only 20% of right-pawed mice were consistent. These results suggest that the development of the CC affects consistency of laterality in a side-dependent manner. These results are discussed considering the role of the CC in the establishment of behavioral lateralization.

  7. Functional reorganization of the auditory pathways (or lack thereof) in callosal agenesis is predicted by monaural sound localization performance.

    Science.gov (United States)

    Paiement, Philippe; Champoux, François; Bacon, Benoit A; Lassonde, Maryse; Mensour, Boualem; Leroux, Jean-Maxime; Lepore, Franco

    2010-01-01

    Neuroimaging studies show that permanent peripheral lesions such as unilateral deafness cause functional reorganization in the auditory pathways. However, functional reorganization of the auditory pathways as a result of higher-level damage or abnormalities remains poorly investigated. A relatively recent behavioural study points to functional changes in the auditory pathways in some, but interestingly not in all, of the acallosal individuals that were tested. The present study uses fMRI to investigate auditory activities in both cerebral hemispheres in those same acallosal subjects in order to directly investigate the contributions of ipsilateral and contralateral functional pathways reorganization. Predictions were made that functional reorganization could be predicted from behavioural performance. As reported previously in a number of neuroimaging studies, results showed that in neurologically intact subjects, binaural stimulation induced balanced activities between both hemispheres, while monaural stimulation induced strong contralateral activities and weak ipsilateral activities. In accordance with behavioural predictions, some acallosal subjects showed patterns of auditory cortical activities that were similar to those observed in neurologically intact subjects while others showed functional reorganization of the auditory pathways. Essentially they showed a significant increase and a significant decrease of neural activities in the contralateral and/or ipsilateral pathways, respectively. These findings indicate that at least in some acallosal subjects, functional reorganization inside the auditory pathways does contribute to compensate for the absence of the corpus callosum.

  8. 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...

  9. See-through Brains and Diffusion Tensor MRI Clarified Fiber Connections: A Preliminary Microstructural Study in a Mouse with Callosal Agenesis.

    Science.gov (United States)

    Kerever, Aurelien; Kamagata, Koji; Yokosawa, Suguru; Otake, Yosuke; Ochi, Hisaaki; Yamada, Taihei; Hori, Masaaki; Kamiya, Kouhei; Nishikori, Akira; Aoki, Shigeki; Arikawa-Hirasawa, Eri

    2015-01-01

    Clearing methods that render the brain optically transparent allow high-resolution three-dimensional (3D) imaging of neural networks. We used diffusion tensor imaging (DTI) and two-photon imaging of cleared brains to analyze white matter in BTBR mice. We confirmed corpus callosum agenesis and identified an abnormal commissure close to the third ventricle. DTI and cleared-brain two-photon imaging revealed that these commissural fibers constituted a frontal clustering of the ventral hippocampal commissure and provided a detailed assessment of white matter structure in mice.

  10. Callosal agenesis and absence of primary visual cortex induced by prenatal X rays impair navigation's strategy and learning in tasks involving visuo-spatial working but not reference memory in mice.

    Science.gov (United States)

    Vitral, Renan Wesley Farinazzo; Vitral, Cristiani Moreira; Dutra, Marcelo Luiz

    2006-03-13

    This study was designed for the identification of possible and distinct abilities for behavioral recovery after prenatal cerebral damage. We adopted an interesting tool for promotion of cell's death. Due to the fact that neuroblastic cells and early postmitotic neurons on the beginning of differentiation are particularly sensible for the promotion of apoptosis, we used a low whole-body dose of X radiation on pregnant female mice on E16 (sixteenth gestational day) to promote damage on specific cerebral areas of the progeny, given that the pattern of cerebral neurogenesis is not homogeneous. The morphological results were previously described by our team. Here we noticed that the recovery of behavioral functions after prenatal damage seems to be related to specific factors of local cortical circuitry organization. The deficits found on visual navigation and working memory contrast with the recovery of primary visual functions and also with reference memory, where the mice have a delay on acquisition of learning but get it. As a conclusion we reasoning that changes on laminar organization on frontal cortex as well as the inter hemispheric cortical integration through the corpus callosum could promote relatively fixed cognitive dysfunctions, as those observed on performances that require strategies for navigation (decision making) and working memory, with consequences also observed on the subsequent learning.

  11. Callosal agenesis complicated by intracranial polylipoma in a newborn infant%新生儿胼胝体缺如并颅内多发脂肪瘤1例

    Institute of Scientific and Technical Information of China (English)

    祝立平; 李贵南; 徐和平; 李晓明; 孙正香

    2009-01-01

    @@ 1 临床资料 女,17 d,因窒息复苏后肌张力高17 d入院.患儿系第1胎第1产,孕40周经阴道分娩,出生体重3 010 g,出生时有窒息史,Apgar评分:1 min 4分,5 min 8分,10 min 10分.羊水Ⅱ度,予复苏处理后,患儿呼吸心率稳定,面色红润.生后第2天患儿出现喜用劲,肌张力偏高,无抽搐.母乳喂养,吸吮好,体重增长满意,大小便正常.患儿母亲孕期无特殊,家族史无异常.体查:T 37℃,R 40 次/分,P 125次/分,BP 65/30 mmHg,体重3 375 g.肺部、心脏及腹部体征无异常.

  12. Features of MRI and clinical analysis of callosal agenesis in 53 cases%胼胝体发育不全53例MRI特点与临床分析

    Institute of Scientific and Technical Information of China (English)

    刘其春; 高祚芝; 王宏波; 郑律

    2009-01-01

    胼胝体发育不全(Agenesis of the corpus callosum,ACC)是小儿常见的先天性颅脑发育畸形。1899年由Bruce首次描述,以后相继有多个类似病例的报道,其发病率约为1∶4000,ACC可以单独存在,但多数ACC合并有其他中枢神经系统先天畸形。MRI可以显示CT不易发现的胼胝体特征性改变,是脑先天发育不良患者最有价值的影像学检查方法。现回顾性分析53例ACC患者的MRI表现,并探讨其与病因及临床症状的关系。

  13. 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.

  14. Alien hand syndrome following corpus callosum infarction: A case report and review of the literature

    Science.gov (United States)

    Gao, Xiaoyu; Li, Bing; Chu, Wenzheng; Sun, Xuwen; Sun, Chunjuan

    2016-01-01

    Alien hand syndrome (AHS) is characterized by involuntary and autonomous activity of the affected limbs, and consists of the frontal, callosal and posterior AHS variants. The callosal subtype, resulting from damage to the corpus callosum, frequently features intermanual conflict. However, infarction of the corpus callosum is rare due to abundant blood supply. The present study reported a case of AHS (callosal subtype, in the right hand) caused by callosal infarction. Infarction of the left corpus callosum was confirmed with magnetic resonance imaging. In addition, magnetic resonance angiography and digital subtraction angiography examinations revealed multiple lesions in the feeding arteries. Subsequent to antiplatelet therapy for 2 weeks following admission, the patient gradually recovered. Furthermore, the current study reviewed 31 previously reported cases of AHS following callosal infarction in the literature. PMID:27698701

  15. 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

    2012-02-23

    The corpus callosum is the most prominent commissural connection between the cortical hemispheres, and numerous neurodevelopmental disorders are associated with callosal agenesis. By using mice either with meningeal overgrowth or selective loss of meninges, we have 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 antagonize the inhibitory effects of BMP7. Wnt3 expression in the cingulate callosal pathfinding axons is developmentally regulated by another BMP family member, GDF5, which is 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.

  16. Alien hand syndrome following corpus callosum infarction: A case report and review of the literature.

    Science.gov (United States)

    Gao, Xiaoyu; Li, Bing; Chu, Wenzheng; Sun, Xuwen; Sun, Chunjuan

    2016-10-01

    Alien hand syndrome (AHS) is characterized by involuntary and autonomous activity of the affected limbs, and consists of the frontal, callosal and posterior AHS variants. The callosal subtype, resulting from damage to the corpus callosum, frequently features intermanual conflict. However, infarction of the corpus callosum is rare due to abundant blood supply. The present study reported a case of AHS (callosal subtype, in the right hand) caused by callosal infarction. Infarction of the left corpus callosum was confirmed with magnetic resonance imaging. In addition, magnetic resonance angiography and digital subtraction angiography examinations revealed multiple lesions in the feeding arteries. Subsequent to antiplatelet therapy for 2 weeks following admission, the patient gradually recovered. Furthermore, the current study reviewed 31 previously reported cases of AHS following callosal infarction in the literature.

  17. 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.

  18. The development of the corpus callosum in the healthy human brain.

    Science.gov (United States)

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

    2010-08-18

    The corpus callosum changes structurally throughout life, but most dramatically during childhood and adolescence. Even so, existing studies of callosal development tend to use parcellation schemes that may not capture the complex spatial profile of anatomical changes. Thus, more detailed mapping of callosal growth processes is desirable to create a normative reference. This will help to relate and interpret other structural, functional, and behavioral measurements, both from healthy subjects and pediatric patients. We applied computational surface-based mesh-modeling methods to analyze callosal morphology at extremely high spatial resolution. We mapped callosal development and explored sex differences in a large and well matched sample of healthy children and adolescents (n = 190) aged 5-18 years. Except for the rostrum in females, callosal thickness increased across the whole surface, with sex- and region-specific rates of growth, and at times shrinkage. The temporally distinct changes in callosal thickness are likely to be a consequence of varying degrees of axonal myelination, redirection, and pruning. Alternating phases of callosal growth and shrinkage may reflect a permanent adjustment and fine-tuning of fibers connecting homologous cortical areas during childhood and adolescence. Our findings emphasize the importance of taking into account sex differences in future studies, as existing developmental effects might remain disguised (or biased toward the effect of the dominant sex in unbalanced statistical designs) when pooling male and female samples.

  19. 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

    According to an established concept, injury of the phloem triggers local sieve plate occlusion including callose-mediated constriction and, possibly, protein plugging of the sieve pores. Sieve plate occlusion can also be achieved by distant stimuli, depends on the passage of electropotential waves......) suddenly dispersed, as observed at 3-4 cm from the stimulus site. The dispersion was reversible; the forisomes had fully re-contracted 7-15 min after burning. Meanwhile, callose appeared at the sieve pores in response to the heat shock. Callose production reached a maximum after 20 min and was also...

  20. Facial emotion recognition in agenesis of the corpus callosum

    OpenAIRE

    Bridgman, Matthew W.; Brown, Warren S.; Spezio, Michael L.; Leonard, Matthew K.; Adolphs, Ralph; Paul, Lynn K.

    2014-01-01

    Background: Impaired social functioning is a common symptom of individuals with developmental disruptions in callosal connectivity. Among these developmental conditions, agenesis of the corpus callosum provides the most extreme and clearly identifiable example of callosal disconnection. To date, deficits in nonliteral language comprehension, humor, theory of mind, and social reasoning have been documented in agenesis of the corpus callosum. Here, we examined a basic social ability as yet not ...

  1. 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.

  2. Structural organization of the corpus callosum predicts the extent and impact of cortical activity in the nondominant hemisphere.

    Science.gov (United States)

    Putnam, Mary Colvin; Wig, Gagan S; Grafton, Scott T; Kelley, William M; Gazzaniga, Michael S

    2008-03-12

    Diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) were combined to examine the relationship between callosal organization and cortical activity across hemispheres. Healthy young adults performed an incidental verbal encoding task (semantic judgments on words) while undergoing fMRI. Consistent with previous studies, the verbal encoding task was associated with left-lateralized activity in the inferior prefrontal cortex (LIPFC). When subjects were divided into two groups based on fractional anisotropy (FA) values in the anterior corpus callosum (DTI), individuals with low anterior callosal FA were found to exhibit greater activity in a homologous region within the right inferior prefrontal cortex (RIPFC) relative to those with high anterior callosal FA. Interestingly, whereas the magnitude of RIPFC activity did not negatively impact subsequent verbal memory performance for individuals with low anterior callosal FA, greater RIPFC activity during verbal encoding was associated with poorer subsequent memory performance for individuals with high anterior callosal FA. Together, these findings provide novel evidence that individual differences in callosal organization are related to the extent of nondominant cortical activity during performance during a lateralized task, and further, that this relationship has consequences on behavior.

  3. 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.

  4. 同源四倍体水稻胚乳发育:糊粉层细胞壁纤维素物质发育、胚乳淀粉积累及胼胝质"套"的形成%Endosperm Development in Autotetraploid Rice: The Development of the Cellulose Wall of Aleuronic Layer Cell, Starch Accumulation of Endosperm and Formation of a Callose "Sheath-like" Structure

    Institute of Scientific and Technical Information of China (English)

    王兰; 刘向东; 卢永根; 冯九焕; 徐雪宾; 徐是雄

    2004-01-01

    利用荧光显微术观察,发现同源四倍体水稻与其二倍体原种的糊粉层细胞壁纤维素物质都存在一个"充实"的过程.授粉后5~6 d,糊粉层开始分化形成,此时其细胞壁上未观察到纤维素物质;授粉后6~8 d,糊粉层细胞壁上开始积累纤维素物质;授粉后8~9 d,糊粉层细胞壁积累了大量的纤维素物质.胚乳淀粉的积累存在一个变化的过程:初生胚乳核周围可见一些淀粉体,随着胚乳游离核的增多,游离核周围淀粉体的数量逐渐减少,胚乳细胞化后,胚乳细胞内开始大量形成淀粉体.利用苯胺蓝染色连续切片荧光观察,发现同源四倍体水稻及其二倍体原种胚乳发育过程中,在珠心表皮和内珠被之间存在一层胼胝质物质,围绕着胚囊并包裹住珠心呈"套"状.这个结构的形成变化过程为:授粉后30 min在珠孔端珠心表皮细胞与内珠被之间开始积累少量的胼胝质,之后胼胝质逐渐增多并向合点端扩展延伸;授粉后1~2 d包裹着整个胚囊外的珠心而仅在维管束处断开;授粉后9~13 d,胼胝质"套"消失.该结构可能与胚和胚乳在发育期间的水分和养分的调节等有密切关系.同源四倍体水稻还存在糊粉层细胞壁发育不同步、糊粉层细胞壁结构异常以及胼胝质"套"不消失等异常现象.这些现象有可能会影响同源四倍体水稻的结实率.

  5. Structural and functional reorganization of the corpus callosum between the age of 6 and 8 years.

    Science.gov (United States)

    Westerhausen, René; Luders, Eileen; Specht, Karsten; Ofte, Sonja H; Toga, Arthur W; Thompson, Paul M; Helland, Turid; Hugdahl, Kenneth

    2011-05-01

    The establishment of an efficient exchange of information between the cerebral hemispheres is of crucial importance in the developing functionally lateralized brain. The corpus callosum, the major connection between the cerebral hemispheres, grows constantly throughout childhood and adolescence. However, behavioral studies suggest the existence of a critical time period for callosal functional development starting around the age of 6 years. In the present longitudinal study, examining a cohort of 20 children at the age of 6 and 8 years, we assessed the relationship between structural and functional callosal development during this time period. The structural development was quantified by calculating the increase in callosal thickness using a shape-based computational analysis of the mid-sagittal corpus callosum as obtained with magnetic resonance imaging. The functional development was assessed with a speech discrimination task based on the dichotic presentation of consonant-vowel syllables. The statistical analysis revealed that children whose callosal isthmus increased in thickness over the course of 2 years showed a decrease in interhemispheric information transfer. However, children exhibiting a decrease in isthmus thickness revealed an increase in information transfer. These results might indicate a refinement process of the callosal connections to optimize the neuronal communication between the developing cerebral hemispheres.

  6. 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.

  7. 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.

  8. The tumor suppressor Nf2 regulates corpus callosum development by inhibiting the transcriptional coactivator Yap.

    Science.gov (United States)

    Lavado, Alfonso; Ware, Michelle; Paré, Joshua; Cao, Xinwei

    2014-11-01

    The corpus callosum connects cerebral hemispheres and is the largest axon tract in the mammalian brain. Callosal malformations are among the most common congenital brain anomalies and are associated with a wide range of neuropsychological deficits. Crossing of the midline by callosal axons relies on a proper midline environment that harbors guidepost cells emitting guidance cues to instruct callosal axon navigation. Little is known about what controls the formation of the midline environment. We find that two components of the Hippo pathway, the tumor suppressor Nf2 (Merlin) and the transcriptional coactivator Yap (Yap1), regulate guidepost development and expression of the guidance cue Slit2 in mouse. During normal brain development, Nf2 suppresses Yap activity in neural progenitor cells to promote guidepost cell differentiation and prevent ectopic Slit2 expression. Loss of Nf2 causes malformation of midline guideposts and Slit2 upregulation, resulting in callosal agenesis. Slit2 heterozygosity and Yap deletion both restore callosal formation in Nf2 mutants. Furthermore, selectively elevating Yap activity in midline neural progenitors is sufficient to disrupt guidepost formation, upregulate Slit2 and prevent midline crossing. The Hippo pathway is known for its role in controlling organ growth and tumorigenesis. Our study identifies a novel role of this pathway in axon guidance. Moreover, by linking axon pathfinding and neural progenitor behaviors, our results provide an example of the intricate coordination between growth and wiring during brain development.

  9. Multiple intracranial lipoma

    Directory of Open Access Journals (Sweden)

    B P Venkatesh

    2014-01-01

    Full Text Available Intracranial lipomas are rare congenital, non-neoplastic lesions discovered incidentally on computerised tomography (CT or magnetic resonance imaging (MRI with an incidence rate of less than 0.1% of all intracranial tumours. Most lipomas are asymptomatic pericallosal lesions sometimes presenting with seizures or headache. Corpus callosum agenesis and defects of midline structures differentiation may be present. Callosal lipomas are of two types: Anterior bulky tubulonodular variety associated with forebrain and rostral callosal anomalies, and posterior ribbon-like curvilinear lipoma generally seen with a normal or near normal corpus callosum. Corpus callosal hypogenesis/agenesis is seen in up to 90% of anterior and 30% of posterior pericallosal lipomas. The association of corpus callosal lipoma with choroid plexus lipoma is variable with its reported incidence rate being 20-50%. A 50-year-old patient was referred to our department for CT scan of brain with history of recent onset of headache and one episode of seizure. We present the imaging findings in this rare case of callosal tubulonodular lipoma having prominent intralesional vessels and extensive calcification with a concomitant intraventricular lipoma in a patient with dysgenetic corpus callosum.

  10. Wnt-induced calcium signaling mediates axon growth and guidance in the developing corpus callosum.

    Science.gov (United States)

    Hutchins, B Ian; Li, Li; Kalil, Katherine

    2012-01-10

    Wnt5a gradients guide callosal axons by repulsion through Ryk receptors in vivo. We recently found that Wnt5a repels cortical axons and promotes axon outgrowth through calcium signaling in vitro. Here, using cortical slices, we show that Wnt5a signals through Ryk to guide and promote outgrowth of callosal axons after they cross the midline. Calcium transient frequencies in callosal growth cones positively correlate with axon outgrowth rates in vitro. In cortical slices, calcium release through inositol 1,4,5-trisphosphate (IP(3)) receptors and calcium entry through transient receptor potential channels modulate axon growth and guidance. Knocking down Ryk inhibits calcium signaling in cortical axons, reduces rates of axon outgrowth subsequent to midline crossing, and causes axon guidance defects. Calcium- and calmodulin-dependent protein kinase II (CaMKII) is required downstream of Wnt-induced calcium signaling for postcrossing callosal axon growth and guidance. Taken together, these results suggest that growth and guidance of postcrossing callosal axons by Wnt-Ryk-calcium signaling involves axon repulsion through CaMKII.

  11. Application of fused lasso logistic regression to the study of corpus callosum thickness in early Alzheimer's disease.

    Science.gov (United States)

    Lee, Sang H; Yu, Donghyeon; Bachman, Alvin H; Lim, Johan; Ardekani, Babak A

    2014-01-15

    We propose a fused lasso logistic regression to analyze callosal thickness profiles. The fused lasso regression imposes penalties on both the l1-norm of the model coefficients and their successive differences, and finds only a small number of non-zero coefficients which are locally constant. An iterative method of solving logistic regression with fused lasso regularization is proposed to make this a practical procedure. In this study we analyzed callosal thickness profiles sampled at 100 equal intervals between the rostrum and the splenium. The method was applied to corpora callosa of elderly normal controls (NCs) and patients with very mild or mild Alzheimer's disease (AD) from the Open Access Series of Imaging Studies (OASIS) database. We found specific locations in the genu and splenium of AD patients that are proportionally thinner than those of NCs. Callosal thickness in these regions combined with the Mini Mental State Examination scores differentiated AD from NC with 84% accuracy.

  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. Astroglial-Mediated Remodeling of the Interhemispheric Midline Is Required for the Formation of the Corpus Callosum

    Directory of Open Access Journals (Sweden)

    Ilan Gobius

    2016-10-01

    Full Text Available The corpus callosum is the major axon tract that connects and integrates neural activity between the two cerebral hemispheres. Although ∼1:4,000 children are born with developmental absence of the corpus callosum, the primary etiology of this condition remains unknown. Here, we demonstrate that midline crossing of callosal axons is dependent upon the prior remodeling and degradation of the intervening interhemispheric fissure. This remodeling event is initiated by astroglia on either side of the interhemispheric fissure, which intercalate with one another and degrade the intervening leptomeninges. Callosal axons then preferentially extend over these specialized astroglial cells to cross the midline. A key regulatory step in interhemispheric remodeling is the differentiation of these astroglia from radial glia, which is initiated by Fgf8 signaling to downstream Nfi transcription factors. Crucially, our findings from human neuroimaging studies reveal that developmental defects in interhemispheric remodeling are likely to be a primary etiology underlying human callosal agenesis.

  14. Working memory and corpus callosum microstructural integrity after pediatric traumatic brain injury: a diffusion tensor tractography study.

    Science.gov (United States)

    Treble, Amery; Hasan, Khader M; Iftikhar, Amal; Stuebing, Karla K; Kramer, Larry A; Cox, Charles S; Swank, Paul R; Ewing-Cobbs, Linda

    2013-10-01

    Deficits in working memory (WM) are a common consequence of pediatric traumatic brain injury (TBI) and are believed to contribute to difficulties in a range of cognitive and academic domains. Reduced integrity of the corpus callosum (CC) after TBI may disrupt the connectivity between bilateral frontoparietal neural networks underlying WM. In the present investigation, diffusion tensor imaging (DTI) tractography of eight callosal subregions (CC1-CC8) was examined in relation to measures of verbal and visuospatial WM in 74 children sustaining TBI and 49 typically developing comparison children. Relative to the comparison group, children with TBI demonstrated poorer visuospatial WM, but comparable verbal WM. Microstructure of the CC was significantly compromised in brain-injured children, with lower fractional anisotropy (FA) and higher axial and radial diffusivity metrics in all callosal subregions. In both groups of children, lower FA and/or higher radial diffusivity in callosal subregions connecting anterior and posterior parietal cortical regions predicted poorer verbal WM, whereas higher radial diffusivity in callosal subregions connecting anterior and posterior parietal, as well as temporal, cortical regions predicted poorer visuospatial WM. DTI metrics, especially radial diffusivity, in predictive callosal subregions accounted for significant variance in WM over and above remaining callosal subregions. Reduced microstructural integrity of the CC, particularly in subregions connecting parietal and temporal cortices, may act as a neuropathological mechanism contributing to long-term WM deficits. The future clinical use of neuroanatomical biomarkers may allow for the early identification of children at highest risk for WM deficits and earlier provision of interventions for these children.

  15. Assessing prenatal white matter connectivity in commissural agenesis.

    Science.gov (United States)

    Kasprian, Gregor; Brugger, Peter C; Schöpf, Veronika; Mitter, Christian; Weber, Michael; Hainfellner, Johannes A; Prayer, Daniela

    2013-01-01

    Complete or partial agenesis of the corpus callosum are rather common developmental abnormalities, resulting in a wide spectrum of clinical neurodevelopmental deficits. Currently, a significant number of these cases are detected by prenatal sonography during second trimester screening examinations. However, major uncertainties about a detailed morphological diagnosis and the clinical significance do not allow accurate prenatal counselling. Here, we were able to demonstrate the 3D connectivity of aberrant commissural tracts in 16 cases with complete and four cases with partial callosal agenesis using the foetal magnetic resonance imaging techniques of diffusion tensor imaging and tractography in utero and in vivo between gestational weeks 20 and 37. The 'misguided' pre-myelinated callosal axons that represent the bundle of Probst were non-invasively visualized, and they showed a degree of structural integrity similar to that of the callosal pathways of age-matched foetuses without cerebral pathologies. In two foetuses, we were able to prove, by post-mortem histology, that diffusion tensor imaging allows the depiction of the bundle of Probst, even during early stages of pre-myelination at 20 and 22 gestational weeks. In cases with partial callosal agenesis, an aberrant sigmoid-shaped bundle was prenatally depicted, confirming the findings of heterotopic interhemispheric connectivity in adults with partial callosal agenesis. In addition to the corpus callosum, other white matter pathways were also involved, including somatosensory and motor pathways that showed significantly higher fractional anisotropy values in cases with callosal agenesis compared with control subjects. A detailed prenatal assessment of abnormal white matter connectivity in cases of midline anomalies will help to explain and understand the clinical heterogeneity in these cases, taking future foetal neurological counselling strategies to a new level.

  16. One hundred million years of interhemispheric communication: the history of the corpus callosum

    Directory of Open Access Journals (Sweden)

    F. Aboitiz

    2003-04-01

    Full Text Available Analysis of regional corpus callosum fiber composition reveals that callosal regions connecting primary and secondary sensory areas tend to have higher proportions of coarse-diameter, highly myelinated fibers than callosal regions connecting so-called higher-order areas. This suggests that in primary/secondary sensory areas there are strong timing constraints for interhemispheric communication, which may be related to the process of midline fusion of the two sensory hemifields across the hemispheres. We postulate that the evolutionary origin of the corpus callosum in placental mammals is related to the mechanism of midline fusion in the sensory cortices, which only in mammals receive a topographically organized representation of the sensory surfaces. The early corpus callosum may have also served as a substrate for growth of fibers connecting higher-order areas, which possibly participated in the propagation of neuronal ensembles of synchronized activity between the hemispheres. However, as brains became much larger, the increasingly longer interhemispheric distance may have worked as a constraint for efficient callosal transmission. Callosal fiber composition tends to be quite uniform across species with different brain sizes, suggesting that the delay in callosal transmission is longer in bigger brains. There is only a small subset of large-diameter callosal fibers whose size increases with increasing interhemispheric distance. These limitations in interhemispheric connectivity may have favored the development of brain lateralization in some species like humans. "...if the currently received statements are correct, the appearance of the corpus callosum in the placental mammals is the greatest and most sudden modification exhibited by the brain in the whole series of vertebrated animals..." T.H. Huxley (1.

  17. 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

    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...... lateralization in adults with ADHD, or could be a sign of a persisting impairment....

  18. 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 ......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...

  19. Nanoscale glucan polymer network causes pathogen resistance.

    Science.gov (United States)

    Eggert, Dennis; Naumann, Marcel; Reimer, Rudolph; Voigt, Christian A

    2014-02-24

    Successful defence of plants against colonisation by fungal pathogens depends on the ability to prevent initial penetration of the plant cell wall. Here we report that the pathogen-induced (1,3)-β-glucan cell wall polymer callose, which is deposited at sites of attempted penetration, directly interacts with the most prominent cell wall polymer, the (1,4)-β-glucan cellulose, to form a three-dimensional network at sites of attempted fungal penetration. Localisation microscopy, a super-resolution microscopy technique based on the precise localisation of single fluorescent molecules, facilitated discrimination between single polymer fibrils in this network. Overexpression of the pathogen-induced callose synthase PMR4 in the model plant Arabidopsis thaliana not only enlarged focal callose deposition and polymer network formation but also resulted in the exposition of a callose layer on the surface of the pre-existing cellulosic cell wall facing the invading pathogen. The importance of this previously unknown polymeric defence network is to prevent cell wall hydrolysis and penetration by the fungus. We anticipate our study to promote nanoscale analysis of plant-microbe interactions with a special focus on polymer rearrangements in and at the cell wall. Moreover, the general applicability of localisation microscopy in visualising polymers beyond plant research will help elucidate their biological function in complex networks.

  20. On the Longicorn genus Orion, Guér

    NARCIS (Netherlands)

    Ritsema Cz., C.

    1889-01-01

    In the „Genera des Coléoptères” (VIII, p. 300) Lacordaire, in accordance with Guérin’s views, ascribes to the female of Orion patagonus Guér. a prothorax which is more strongly rugose than in the male and the callosities of which are less numerous and but little conspicuous. Now the Leyden Museum po

  1. Anarchic-Hand Syndrome: ERP Reflections of Lost Control over the Right Hemisphere

    Science.gov (United States)

    Verleger, Rolf; Binkofski, Ferdinand; Friedrich, Monique; Sedlmeier, Peter; Kompf, Detlef

    2011-01-01

    In patients with the callosal type of anarchic-hand syndrome, the left hand often does not act as intended and counteracts the right hand. Reports are scarce about the underlying neurophysiological mechanisms. We report the case G.H. who developed the syndrome after infarction of the left arteria pericallosa. It has been suggested that the…

  2. Systematics and Distribution of Siphocypraea mus and Propustularia surinamensis (Gastropoda, Cypraeidae)

    NARCIS (Netherlands)

    Coomans, H.E.

    1963-01-01

    The systematic place of “Cypraea” mus Linné is discussed, and it is concluded that the species belongs in Siphocypraea (Akleistostoma). The “varieties” tuberculata Gray and bicornis Sowerby should be withdrawn; they are only forms with callosities. Callus formations are often found in Cypraeidae. Th

  3. Refractory seizures with global developmental delay: A rare cause

    Directory of Open Access Journals (Sweden)

    P N Vinoth

    2011-01-01

    Full Text Available Aicardi syndrome is a genetic disorder characterized by the triad of infantile spasm in flexion, callosal agenesis and ocular abnormalities (chorioretinal lacunae, coloboma of optic disc. We report a typical case of Aicardi syndrome with all the classical features.

  4. 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

  5. Genetic dissection of basal defence responsiveness in accessions of Arabidopsis thaliana

    NARCIS (Netherlands)

    Ahmad, S.; Hulten, M. van; Martin, J.; Pieterse, C.M.J.; Wees, S.C.M. van; Ton, J.

    2011-01-01

    Basal resistance involves a multitude of pathogen- and herbivore-inducible defence mechanisms, ranging from localized callose deposition to systemic defence gene induction by salicylic acid (SA) and jasmonic acid (JA). In this study, we have explored and dissected genetic variation in the responsive

  6. Plant basal resistance: genetics, biochemistry, and impacts on plant-biotic interactions

    NARCIS (Netherlands)

    Ahmad, S.

    2012-01-01

    Basal resistance depends largely on a diverse range of defence mechanisms that become active upon attack by pathogens or insects. These mechanisms range from rapid stomatal closure and production of reactive oxygen species, to callose deposition and defence gene induction. It is commonly assumed tha

  7. 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 be

  8. Intracranial Convexity Lipoma with Massive Calcification: Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eung Tae; Park, Dong Woo; Ryu, Jeong Ah; Park, Choong Ki; Lee, Young Jun; Lee, Seung Ro [Dept. of Radiology, Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2011-12-15

    Intracranial lipoma is a rare entity, accounting for less than 0.5% of intracranial tumors, which usually develops in the callosal cisterns. We report a case of lipoma with an unusual location; in the high parietal convexity combined with massive calcification, and no underlying vascular malformation or congenital anomaly.

  9. Immunocytochemical characterization of the cell walls of bean cell suspensions during habituation and dehabituation to dichlobenil

    DEFF Research Database (Denmark)

    Garcia-Angulo, P.; Willats, W. G. T.; Encina, A. E.

    2006-01-01

    analysed showed calcofluor-stained appositions. However, in habituated and dehabituated cells, appositions were not recognized by an anticallose antibody. This finding suggested the accumulation of an extracellular polysaccharide different to callose, probably a 1,4-ß-glucan in these cell lines...

  10. 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

  11. 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...

  12. [Diagnostic dyspraxia and frontal syndrome].

    Science.gov (United States)

    Donnet, A; Schmitt, A; Poncet, M

    1998-05-01

    A 27-year-old ambidexter woman experienced a clinical and psychometric frontal syndrome associated with a partial callosal syndrome following transcallosal surgery for an intraventricular neurocytoma. She also complained of difficulties with her left hand which realized a particular form of diagnostic dyspraxia: there were specific features of an isolated dysfunction of the control of the realization of a program.

  13. Priming for JA-dependent defenses using hexanoic acid is an effective mechanism to protect Arabidopsis against B. cinerea.

    Science.gov (United States)

    Kravchuk, Zhana; Vicedo, Begonya; Flors, Víctor; Camañes, Gemma; González-Bosch, Carmen; García-Agustín, Pilar

    2011-03-01

    Soil drench treatments with hexanoic acid can effectively protect Arabidopsis plants against Botrytis cinerea through a mechanism based on a stronger and faster accumulation of JA-dependent defenses. Plants impaired in ethylene, salicylic acid, abscisic acid or glutathion pathways showed intact protection by hexanoic acid upon B. cinerea infection. Accordingly, no significant changes in the SA marker gene PR-1 in either the SA or ABA hormone balance were observed in the infected and treated plants. In contrast, the JA signaling pathway showed dramatic changes after hexanoic acid treatment, mainly when the pathogen was present. The impaired JA mutants, jin1-2 and jar1, were unable to display hexanoic acid priming against the necrotroph. In addition, hexanoic acid-treated plants infected with B. cinerea showed priming in the expression of the PDF1.2, PR-4 and VSP1 genes implicated in the JA pathways. Moreover, JA and OPDA levels were primed at early stages by hexanoic acid. Treatments also stimulated increased callose accumulation in response to the pathogen. Although callose accumulation has proved an effective IR mechanism against B. cinerea, it is apparently not essential to express hexanoic acid-induced resistance (HxAc-IR) because the mutant pmr4.1 (callose synthesis defective mutant) is protected by treatment. We recently described how hexanoic acid treatments can protect tomato plants against B. cinerea by stimulating ABA-dependent callose deposition and by priming OPDA and JA-Ile production. We clearly demonstrate here that Hx-IR is a dependent plant species, since this acid protects Arabidopsis plants against the same necrotroph by priming JA-dependent defenses without enhancing callose accumulation.

  14. 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)

  15. Pollen grain of barley (Hordeum vulgare L. - pattern of development

    Directory of Open Access Journals (Sweden)

    Maria Charzyńska

    2014-01-01

    Full Text Available Pollen development in barley follows the general pattern established for other species of Poaceae: 1 microspore division occurs at the vacuolate microspore stage with polarly located nucleus; 2 microspore mitosis is immediately followed by phragmoplast and cell plate formation; 3 in consequence or unequal microspore division, the generative cell, at first attached to the pollen wall, is separated from the vegetative cell by a callosic wall; 4 during the postmitotic two-cell stage of development, the vegetative nucleus migrates to the aperture pole and is followed by the generative cell that is detached and free of callose wall. In this position the generative cell divides into two sperm cells. These data do not confirm the interpretation of pollen grain development in barley given by Cass and Karas in Can. J. Bot. 53: 1051-1062, 1975.

  16. Development of the pollen in the antarctic flowering plant Colobanthus quitensis (Kunth Bartl.

    Directory of Open Access Journals (Sweden)

    Irena Giełwanowska

    2012-12-01

    Full Text Available Colobanthus quitensis (Kunth Bartl. produced two types very small bisexual fl owers. In the Antarctic natural conditions chasmogamic and cleistogamic fl owers most often form fi ve stamina with short fi laments. Two microsporangia with a three-layer wall form in the anther. Microspore mother cells, which develop into microspores after meiosis, form inside the microsporangium. Microsporocytes of Colobanthus quitensis are surrounded with a thick callose layer, the special wall. After meiosis, the callose wall is dissolved and microspores are released from the tetrad. The production of proorbicules, orbicules and peritapetal membrane, and the construction of a complex sporoderm with numerous apertural sites were observed. When microspore and pollen protoplasts underwent necrosis, probably as a result of temperature and osmotic stress, sporoderm layers formed around microspores, and the cell tapetum did not disintegrate. However, woody wall layers did not accumulate in endothecium cells.

  17. Acute infarct of the corpus callosum presenting as alien hand syndrome: evidence of diffusion weighted imaging and magnetic resonance angiography

    Directory of Open Access Journals (Sweden)

    Yuan Jun

    2011-11-01

    Full Text Available Abstract Background Infarcts of the corpus callosum are rare and have not been well documented previously. As for a variety of signs and symptoms presented, alien hand syndrome (AHS can be easily overlooked. Case presentation In this report, we present a patient with a mixed types of AHS coexistence secondary to the corpus callosum infarction, including a motor type of AHS by intermanual conflict (callosal type AHS and a sensory type of AHS by alien hand and left hemianesthesia (posterior AHS. Conclusions Our case may contribute to the early recognition of AHS and to explore the abnormal neural mechanism of AHS. To our knowledge, rare reports have ever documented such mixed AHS coexisting secondary to the callosal lesion, based on advanced neuroimaging methods as in our case.

  18. 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.

  19. 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.

  20. Thermal Imaging of Skin Changes on the Feet of Type II Diabetics

    Science.gov (United States)

    2007-11-02

    Austria Abstract – Skin changes such as callosities and mycosis may be regarded as a risk factor for severe structural impairments including...normal individuals in a survey conducted in Canada [10]. Most onychomycoses are secondary to a mycosis of the adjacent skin [11], which may lead to...Measure Intraclass Correlation (95 % confidence interval) callus mycosis Toe deformity Arch deformity Hot spot 1st right toe 0.23 (0.00

  1. The pig-tailed monkey (Macaca nemestrina) as a space-flight candidate. [for cardiovascular studies

    Science.gov (United States)

    Pace, N.; Rahlmann, D. F.; Kodama, A. M.; Grunbaum, B. W.; Mains, R. C.

    1977-01-01

    Scientific attributes which make the pig-tailed monkey an optimal candidate for studing the nature of cardiovascular and respiratory adaptations in man during exposure to high altitutes for long periods of time include: a calm, quiet, patient temperament; a short tail and the presence of ischial callosities permitting comfortable seated restraint during long duration experiments; and the close phylogenetic relationships and comparable body size to man.

  2. Documentation for the CETACEA Database of Marine Mammal Literature References. Revision

    Science.gov (United States)

    1990-06-01

    dimorphism 933 Sexual maturity 989 Weaning 742 Age estimation baleen 370 BT Baleen 129 Age estimation bone 390 BT Osteology 717 Age estimation corpora...bilateral anatomical asymmetry. RT Blow 153 Blowhole 157 Picrmentation 233 Osteology 717 Respiratory system 861 Skull 257 Attacking Agonistic behavior 570... Osteology 717 Paleontology 733 Skull 257 Vertebral formula 740 Bonnet Callosities 165 Dermal hardening 285 Field marks 413 Individual identification 529

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

    OpenAIRE

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

    2014-01-01

    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 t...

  4. 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.

  5. 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

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

    OpenAIRE

    Louis Albertini; Helene Grenet-Auberger; Andre Souvre

    2014-01-01

    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...

  7. Activation of defense against Phytophthora infestans in potato by down-regulation of syntaxin gene expression.

    Science.gov (United States)

    Eschen-Lippold, Lennart; Landgraf, Ramona; Smolka, Ulrike; Schulze, Sebastian; Heilmann, Mareike; Heilmann, Ingo; Hause, Gerd; Rosahl, Sabine

    2012-03-01

    The oomycete Phytophthora infestans is the causal agent of late blight, the most devastating disease of potato. The importance of vesicle fusion processes and callose deposition for defense of potato against Phytophthora infestans was analyzed. Transgenic plants were generated, which express RNA interference constructs targeted against plasma membrane-localized SYNTAXIN-RELATED 1 (StSYR1) and SOLUBLE N-ETHYLMALEIMIDE-SENSITIVE FACTOR ADAPTOR PROTEIN 33 (StSNAP33), the potato homologs of Arabidopsis AtSYP121 and AtSNAP33, respectively. Phenotypically, transgenic plants grew normally, but showed spontaneous necrosis and chlorosis formation at later stages. In response to infection with Phytophthora infestans, increased resistance of StSYR1-RNAi plants, but not StSNAP33-RNAi plants, was observed. This increased resistance correlated with the constitutive accumulation of salicylic acid and PR1 transcripts. Aberrant callose deposition in Phytophthora infestans-infected StSYR1-RNAi plants coincided with decreased papilla formation at penetration sites. Resistance against the necrotrophic fungus Botrytis cinerea was not significantly altered. Infiltration experiments with bacterial solutions of Agrobacterium tumefaciens and Escherichia coli revealed a hypersensitive phenotype of both types of RNAi lines. The enhanced defense status and the reduced growth of Phytophthora infestans on StSYR1-RNAi plants suggest an involvement of syntaxins in secretory defense responses of potato and, in particular, in the formation of callose-containing papillae.

  8. Tractography of the corpus callosum in Huntington's disease.

    Directory of Open Access Journals (Sweden)

    Owen Phillips

    Full Text Available White matter abnormalities have been shown in presymptomatic and symptomatic Huntington's disease (HD subjects using Magnetic Resonance Imaging (MRI and Diffusion Tensor Imaging (DTI methods. The largest white matter tract, the corpus callosum (CC, has been shown to be particularly vulnerable; however, little work has been done to investigate the regional specificity of tract abnormalities in the CC. Thus, this study examined the major callosal tracts by applying DTI-based tractography. Using TrackVis, a previously defined region of interest tractography method parcellating CC into seven major tracts based on target region was applied to 30 direction DTI data collected from 100 subjects: presymptomatic HD (Pre-HD subjects (n=25, HD patients (n=25 and healthy control subjects (n=50. Tractography results showed decreased fractional anisotropy (FA and increased radial diffusivity (RD across broad regions of the CC in Pre-HD subjects. Similar though more severe deficits were seen in HD patients. In Pre-HD and HD, callosal FA and RD were correlated with Disease Burden/CAG repeat length as well as motor (UHDRSI and cognitive (URDRS2 assessments. These results add evidence that CC pathways are compromised prior to disease onset with possible demyelination occurring early in the disease and suggest that CAG repeat length is a contributing factor to connectivity deficits. Furthermore, disruption of these callosal pathways potentially contributes to the disturbances of motor and cognitive processing that characterize HD.

  9. EDS1 contributes to nonhost resistance of Arabidopsis thaliana against Erwinia amylovora.

    Science.gov (United States)

    Moreau, Manon; Degrave, Alexandre; Vedel, Régine; Bitton, Frédérique; Patrit, Oriane; Renou, Jean-Pierre; Barny, Marie-Anne; Fagard, Mathilde

    2012-03-01

    Erwinia amylovora causes fire blight in rosaceous plants. In nonhost Arabidopsis thaliana, E. amylovora triggers necrotic symptoms associated with transient bacterial multiplication, suggesting either that A. thaliana lacks a susceptibility factor or that it actively restricts E. amylovora growth. Inhibiting plant protein synthesis at the time of infection led to an increase in necrosis and bacterial multiplication and reduced callose deposition, indicating that A. thaliana requires active protein synthesis to restrict E. amylovora growth. Analysis of the callose synthase-deficient pmr4-1 mutant indicated that lack of callose deposition alone did not lead to increased sensitivity to E. amylovora. Transcriptome analysis revealed that approximately 20% of the genes induced following E. amylovora infection are related to defense and signaling. Analysis of mutants affected in NDR1 and EDS1, two main components of the defense-gene activation observed, revealed that E. amylovora multiplied ten times more in the eds1-2 mutant than in the wild type but not in the ndr1-1 mutant. Analysis of mutants affected in three WRKY transcription factors showing EDS1-dependent activation identified WRKY46 and WRKY54 as positive regulators and WRKY70 as a negative regulator of defense against E. amylovora. Altogether, we show that EDS1 is a positive regulator of nonhost resistance against E. amylovora in A. thaliana and hypothesize that it controls the production of several effective defenses against E. amylovora through the action of WRKY46 and WRKY54, while WRKY70 acts as a negative regulator.

  10. Spatiotemporal dynamics of bimanual integration in human somatosensory cortex and their relevance to bimanual object manipulation.

    Science.gov (United States)

    Jung, Patrick; Klein, Johannes C; Wibral, Michael; Hoechstetter, Karsten; Bliem, Barbara; Lu, Ming-Kuei; Wahl, Mathias; Ziemann, Ulf

    2012-04-18

    Little is known about the spatiotemporal dynamics of cortical responses that integrate slightly asynchronous somatosensory inputs from both hands. This study aimed to clarify the timing and magnitude of interhemispheric interactions during early integration of bimanual somatosensory information in different somatosensory regions and their relevance for bimanual object manipulation and exploration. Using multi-fiber probabilistic diffusion tractography and MEG source analysis of conditioning-test (C-T) median nerve somatosensory evoked fields in healthy human subjects, we sought to extract measures of structural and effective callosal connectivity between different somatosensory cortical regions and correlated them with bimanual tactile task performance. Neuromagnetic responses were found in major somatosensory regions, i.e., primary somatosensory cortex SI, secondary somatosensory cortex SII, posterior parietal cortex, and premotor cortex. Contralateral to the test stimulus, SII activity was maximally suppressed by 51% at C-T intervals of 40 and 60 ms. This interhemispheric inhibition of the contralateral SII source activity correlated directly and topographically specifically with the fractional anisotropy of callosal fibers interconnecting SII. Thus, the putative pathway that mediated inhibitory interhemispheric interactions in SII was a transcallosal route from ipsilateral to contralateral SII. Moreover, interhemispheric inhibition of SII source activity correlated directly with bimanual tactile task performance. These findings were exclusive to SII. Our data suggest that early interhemispheric somatosensory integration primarily occurs in SII, is mediated by callosal fibers that interconnect homologous SII areas, and has behavioral importance for bimanual object manipulation and exploration.

  11. 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.

  12. Channels of the corpus callosum. Evidence from simple reaction times to lateralized flashes in the normal and the split brain.

    Science.gov (United States)

    Iacoboni, M; Zaidel, E

    1995-06-01

    We studied 75 normal subjects and three commissurotomized patients using unimanual simple reaction times to lateralized flashes as a behavioural estimate of interhemispheric transmission time. Three different versions of the paradigm were performed: (i) the basic task; (ii) a motor task, with an increased complexity of the motor response; and (iii) a visual task, with an increased complexity of the visual stimulus presentation. We tested two hypotheses. First, that the new versions of the simple reaction time task result in shifts in hemispheric specialization for processing motor output (indicated by a main effect of response hand) or visual input (indicated by a main effect of visual field) alone, without affecting callosal transmission. In that case normals and split brain patients would show no significant task by response hand by visual field interaction and no significant task by crossed-uncrossed difference interaction. Secondly, that the new versions of the task affect callosal transfer. In that case, normals, but not split brain patients, would show a significant task by response hand by visual field interaction and a significant task by crossed-uncrossed difference interaction. Results are consistent with the latter hypothesis, showing that the motor task significantly changed the response hand by visual field interaction and the crossed-uncrossed difference, but only in normal subjects, perhaps producing a switch in the callosal channel subserving the interhemispheric transfer.

  13. 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.

  14. Agenesis of the Corpus Callosum Due to Defective Glial Wedge Formation in Lhx2 Mutant Mice.

    Science.gov (United States)

    Chinn, Gregory A; Hirokawa, Karla E; Chuang, Tony M; Urbina, Cecilia; Patel, Fenil; Fong, Jeanette; Funatsu, Nobuo; Monuki, Edwin S

    2015-09-01

    Establishment of the corpus callosum involves coordination between callosal projection neurons and multiple midline structures, including the glial wedge (GW) rostrally and hippocampal commissure caudally. GW defects have been associated with agenesis of the corpus callosum (ACC). Here we show that conditional Lhx2 inactivation in cortical radial glia using Emx1-Cre or Nestin-Cre drivers results in ACC. The ACC phenotype was characterized by aberrant ventrally projecting callosal axons rather than Probst bundles, and was 100% penetrant on 2 different mouse strain backgrounds. Lhx2 inactivation in postmitotic cortical neurons using Nex-Cre mice did not result in ACC, suggesting that the mutant phenotype was not autonomous to the callosal projection neurons. Instead, ACC was associated with an absent hippocampal commissure and a markedly reduced to absent GW. Expression studies demonstrated strong Lhx2 expression in the normal GW and in its radial glial progenitors, with absence of Lhx2 resulting in normal Emx1 and Sox2 expression, but premature exit from the cell cycle based on EdU-Ki67 double labeling. These studies define essential roles for Lhx2 in GW, hippocampal commissure, and corpus callosum formation, and suggest that defects in radial GW progenitors can give rise to ACC.

  15. MR imaging of the corpus callosum in the patients of ischemic cerebrovascular disease

    Energy Technology Data Exchange (ETDEWEB)

    Umahara, Takahiko; Tanaka, Yuriko; Yamaguchi, Katsuhiko; Imamura, Toshiharu; Iwamoto, Toshihiko; Katsunuma, Hideyo (Tokyo Medical Coll. (Japan))

    1990-12-01

    We studied the abnormal MR morphology of the corpus callosum (CC) in 8 cases of progressive subcortical vascular encephalopathy (PSVE), 1 case of anterior cerebral artery (ACA) area hemorrhagic infarction, 5 cases of middle cerebral artery (MCA) area infarction, and 7 cases of posterior cerebral artery (PCA) area infarction (2 cases had bilateral PCA infarction). In addition, we studied the MR imaging of sagittal sulcal lesions of CC (SSLCC), and of inner callosal-subcallosal lesions (or inner callosal-subcallosal laminar hyperintensity; ICLH). PSVE usually showed diffuse attenuations of CC, and findings similar to a localized callosal infarction sometimes were observed. The ACA infarct case showed a rupture of the CC. The MCA infarct cases had focal attenuations (mainly at the body of the CC) caused by secondary degenerations. Only 1 of the 5 cases with unilateral PCA infarction showed a lesion in the splenium of the CC. These results are generally in accord with the results of our previous pathological study of the CC in ischemic cerebrovascular disease. Linear low signal intensity areas at the gneu found in 77% of our MRI cases, and we think these lesions compatible with SSLCC which we have studied previously. ICLH was found in the cases of PSVE, multi-infarct, and clinically normals. We therefore suggest that ICLH seems to have no disease specificity. (author).

  16. Plasmodesmata-mediated intercellular signaling during plant growth and development.

    Science.gov (United States)

    Yadav, Shri R; Yan, Dawei; Sevilem, Iris; Helariutta, Ykä

    2014-01-01

    Plasmodesmata (PD) are cytoplasmic channels that connect neighboring cells for cell-to-cell communication. PD structure and function vary temporally and spatially to allow formation of symplastic domains during different stages of plant development. Reversible deposition of callose at PD plays an important role in controlling molecular trafficking through PD by regulating their size exclusion limit. Previously, we reported several semi-dominant mutants for CALLOSE SYNTHASE 3 (CALS3) gene, which overproduce callose at PD in Arabidopsis. By combining two of these mutations in a LexA-VP16-ER (XVE)-based estradiol inducible vector system, a tool known as the "icals3m system" was developed to temporally obstruct the symplastic connections in a specified spatial domain. The system has been successfully tested and used, in combination with other methods, to investigate the route for mobile signals such as the SHR protein, microRNA165/6, and cytokinins in Arabidopsis roots, and also to understand the role of symplastic domain formation during lateral root development. We envision that this tool may also be useful for identifying tissue-specific symplastic regulatory networks and to analyze symplastic movement of metabolites.

  17. White matter fiber degradation attenuates hemispheric asymmetry when integrating visuomotor information.

    Science.gov (United States)

    Schulte, Tilman; Müller-Oehring, Eva M; Rohlfing, Torsten; Pfefferbaum, Adolf; Sullivan, Edith V

    2010-09-01

    Degradation of white matter fibers can affect the transmission of signals in brain circuits that normally enable integration of highly lateralized visual and motor processes. Here, we used diffusion tensor imaging tractography in combination with functional magnetic resonance imaging to examine the specific contributions of interhemispheric and intrahemispheric white matter fibers to functional measures of hemispheric transfer and parallel information processing using bilateral and unilateral left and right visual field stimulation in normal and compromised systems. In healthy adults, a greater degree of bilateral processing advantage with the left (nondominant) hand correlated with higher integrity of callosal fibers connecting occipital cortices, whereas less unilateral processing advantage with the right hand correlated with higher integrity of left-hemispheric posterior cingulate fibers. In contrast, alcoholics who have compromised callosal integrity showed less bilateral processing advantage than controls when responding with the left hand and greater unilateral processing advantage when responding with the right hand. We also found degraded left posterior cingulate and posterior callosal fibers in chronic alcoholics, which is consistent with functional imaging results of less left posterior cingulate and extrastriate cortex activation in alcoholics than controls when processing bilateral compared with unilateral visual field stimulation. Together, our results demonstrated that interhemispheric and intrahemispheric white matter fiber pathways mediate visuomotor integration asymmetrically and that subtle white matter fiber degradation in alcoholism attenuated the normal pattern of hemispheric asymmetry, which may have ramifications for the efficiency of visual information processing and fast response execution.

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. Enhancement of the citrus immune system provides effective resistance against Alternaria brown spot disease.

    Science.gov (United States)

    Llorens, Eugenio; Fernández-Crespo, Emma; Vicedo, Begonya; Lapeña, Leonor; García-Agustín, Pilar

    2013-01-15

    In addition to basal defense mechanisms, plants are able to develop enhanced defense mechanisms such as induced resistance (IR) upon appropriate stimulation. We recently described the means by which several carboxylic acids protect Arabidopsis and tomato plants against fungi. In this work, we demonstrate the effectiveness of hexanoic acid (Hx) in the control of Alternaria brown spot (ABS) disease via enhancement of the immune system of Fortune mandarin. The application of 1mM Hx in irrigation water to 2-year-old Fortune plants clearly reduced the incidence of the disease and led to smaller lesions. We observed that several of the most important mechanisms involved in induced resistance were affected by Hx application. Our results demonstrate enhanced callose deposition in infected plants treated with Hx, which suggests an Hx priming mechanism. Plants treated with the callose inhibitor 2-DDG were more susceptible to the fungus. Moreover, polygalacturonase-inhibiting protein (PGIP) gene expression was rapidly and significantly upregulated in treated plants. However, treatment with Hx decreased the levels of reactive oxygen species (ROS) in infected plants. Hormonal and gene analyses revealed that the jasmonic acid (JA) pathway was activated due to a greater accumulation of 12-oxo-phytodienoic acid (OPDA) and JA along with a rapid accumulation of JA-isoleucine (JA-Ile). Furthermore, we observed a more rapid accumulation of abscisic acid (ABA), which could act as a positive regulator of callose deposition. Thus, our results support the hypothesis that both enhanced physical barriers and the JA signaling pathway are involved in hexanoic acid-induced resistance (Hx-IR) to Alternaria alternata.

  3. White matter fiber compromise contributes differentially to attention and emotion processing impairment in alcoholism, HIV-infection, and their comorbidity.

    Science.gov (United States)

    Schulte, T; Müller-Oehring, E M; Sullivan, E V; Pfefferbaum, A

    2012-10-01

    Alcoholism (ALC) and HIV-1 infection (HIV) each affects emotional and attentional processes and integrity of brain white matter fibers likely contributing to functional compromise. The highly prevalent ALC+HIV comorbidity may exacerbate compromise. We used diffusion tensor imaging (DTI) and an emotional Stroop Match-to-Sample task in 19 ALC, 16 HIV, 15 ALC+HIV, and 15 control participants to investigate whether disruption of fiber system integrity accounts for compromised attentional and emotional processing. The task required matching a cue color to that of an emotional word with faces appearing between the color cue and the Stroop word in half of the trials. Nonmatched cue-word color pairs assessed selective attention, and face-word pairs assessed emotion. Relative to controls, DTI-based fiber tracking revealed lower inferior longitudinal fasciculus (ilf) integrity in HIV and ALC+HIV and lower uncinate fasciculus (uf) integrity in all three patient groups. Controls exhibited Stroop effects to positive face-word emotion, and greater interference was related to greater callosal, cingulum and ilf integrity. By contrast, HIV showed greater interference from negative Stroop words during color-nonmatch trials, correlating with greater uf compromise. For face trials, ALC and ALC+HIV showed greater Stroop-word interference, correlating with lower cingulate and callosal integrity. Thus, in HIV, conflict resolution was diminished when challenging conditions usurped resources needed to manage interference from negative emotion and to disengage attention from wrongly cued colors (nonmatch). In ALC and ALC+HIV, poorer callosal integrity was related to enhanced emotional interference suggesting curtailed interhemispheric exchange needed between preferentially right-hemispheric emotion and left-hemispheric Stroop-word functions.

  4. 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.

  5. Infarction of the entire corpus callosum as a complication in subarachnoid hemorrhage: A case report

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    Satoru Takahashi, M.D.

    2017-03-01

    Full Text Available The corpus callosum is the major commissural pathway connecting the cerebral hemispheres. This pathway receives its blood supply from anterior communicating artery, pericallosal artery, and posterior pericallosal artery. However, in some cases, the entire corpus callosum is supplied by median callosal artery; thus, occlusion of this artery can lead to infarction of the entire corpus callosum. Few reports have described this type of infarction, and no reports after subarachnoid hemorrhage (SAH exist. Here, we report on a 42-year-old female who was diagnosed with SAH after two aneurysms were discovered in bifurcation of left anterior cerebral artery (A1-A2. After successful clipping was performed, the patient was alert and had no neurological deficits; moreover, the computed tomography images that were acquired after the operation showed no evidence of infarction. Nine days after admittance to the hospital, drowsiness and weakness of the left limbs with brain swelling appeared and decompressive hemi-craniectomy was performed. Diagnostic cerebral angiography revealed vasospasms in both anterior and middle cerebral arteries, thus fasudil hydrochloride was administered intra-arterially. While blood flow in all arteries improved, diffusion-weighted magnetic resonance imaging detected infarction along the entire length of the corpus callosum and in the medial region of the right frontal lobe. We believe this infarction was due to secondary ischemia of median callosal artery. This case reminded us of the anatomical variation wherein median callosal artery is the sole blood supply line for the corpus callosum and demonstrated that infarction of the entire corpus callosum is possible.

  6. 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

  7. The Pseudomonas syringae pv. tomato type III effector HopM1 suppresses Arabidopsis defenses independent of suppressing salicylic acid signaling and of targeting AtMIN7.

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    Anju Gangadharan

    Full Text Available Pseudomonas syringae pv tomato strain DC3000 (Pto delivers several effector proteins promoting virulence, including HopM1, into plant cells via type III secretion. HopM1 contributes to full virulence of Pto by inducing degradation of Arabidopsis proteins, including AtMIN7, an ADP ribosylation factor-guanine nucleotide exchange factor. Pseudomonas syringae pv phaseolicola strain NPS3121 (Pph lacks a functional HopM1 and elicits robust defenses in Arabidopsis thaliana, including accumulation of pathogenesis related 1 (PR-1 protein and deposition of callose-containing cell wall fortifications. We have examined the effects of heterologously expressed HopM1Pto on Pph-induced defenses. HopM1 suppresses Pph-induced PR-1 expression, a widely used marker for salicylic acid (SA signaling and systemic acquired resistance. Surprisingly, HopM1 reduces PR-1 expression without affecting SA accumulation and also suppresses the low levels of PR-1 expression apparent in SA-signaling deficient plants. Further, HopM1 enhances the growth of Pto in SA-signaling deficient plants. AtMIN7 contributes to Pph-induced PR-1 expression. However, HopM1 fails to degrade AtMIN7 during Pph infection and suppresses Pph-induced PR-1 expression and callose deposition in wild-type and atmin7 plants. We also show that the HopM1-mediated suppression of PR-1 expression is not observed in plants lacking the TGA transcription factor, TGA3. Our data indicate that HopM1 promotes bacterial virulence independent of suppressing SA-signaling and links TGA3, AtMIN7, and other HopM1 targets to pathways distinct from the canonical SA-signaling pathway contributing to PR-1 expression and callose deposition. Thus, efforts to understand this key effector must consider multiple targets and unexpected outputs of its action.

  8. Hydration, sporoderm breaking and germination of Cupressus arizonica pollen.

    Science.gov (United States)

    Chichiriccò, G; Spanò, L; Torraca, G; Tartarini, A

    2009-05-01

    In vitro and in vivo rehydration and germination in Cupressus arizonica pollen were examined using light and scanning electron microscopy. Shed pollen has 12.6% water content, which reduced to 8.2% after dispersal, and this latter pollen survived for some months at room temperature and for years at -10 degrees C. Rehydration requires breaking of the sporoderm walls and depends on the composition and pH of the rehydration medium. Acidity restrains the breakage, while alkalinity promotes it. Pollen division follows exine shedding and requires the persistence of the mucilaginous layer; hence, pH values countering these outcomes prevent division. Division results in a large and a small cell separated by a callosic wall. A pollen tube develops from the innermost intine of the large cell, which is callosic, and extends into the mucilaginous middle intine. The percentage germination never exceeded 17% in all tested media. In vivo, pollen rehydrates and casts off the exine in the micropylar drop. Drop withdrawal brings pollen to the apical nucellar cells that degenerate in the meantime, and it leaves a deposit on the surface of the micropylar canal. After contaction of the nucellar cells, the pollen flattens and its mucilaginous layer shrinks and disappears. This occurs simultaneously with sealing of the micropylar canal. During this time, pollen divides asymmetrically without the callosic wall, and the larger cell develops a tube in the interface with the nucellus. Only some pollen grains accomplish adhesion to the nucellus and germinate. The in vitro and in vivo developmental stages are discussed.

  9. Pollen grain sporoderm and types of dispersal units

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    Ettore Pacini

    2014-01-01

    Full Text Available The pollen of gymnosperms and angiosperms may be dispersed in monads, tetrads, polyads, massulae or compact pollinia. The monads and tetrads may form larger clumps of pollen because filiform pollen is tangled while other kinds of pollen can be glued by means of different devices. Exine and intine modify their structure to adapt to pollen dispersing units, exine in some cases can be absent. An additional layer, a thin callosic wall, can be present in some species beneath the intine; this occurs when pollen grains are slightly dehydrated before dispersal.

  10. Storage products and tissue interaction in the ovule of Pinus silvestris (L.

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    F. M. Engels

    2014-01-01

    Full Text Available The organel-sequence in ovular cells of Pinus silvestris was investigated by light- and electronmicroscopy during the post-pollination and pre-fertilization period. Changes in starch and lipid storage suppose starch to be a pool for lipid synthesis and a reserve for ovule development. The base nucellus plays an important role in the distribution of metabolites all over the ovular tissues. Lipid, starch and callose are of interest for the cells to protect them against low temperatures by means of isolation, antifreeze and plug formation respectively.

  11. Congenital malformations of the supratentorial brain. Pt. 2. Disorders of the corpus callosum and holoprosencephalies; Kongenitale Malformationen des Grosshirns. Teil 2: Entwicklungsstoerungen des Balkens und Holoprosenzephalien

    Energy Technology Data Exchange (ETDEWEB)

    Rummeny, C. [Institut fuer Klinische Radiologie, Klinikum der Universitaet Muenchen, Grosshadern, Muenchen (Germany); Institut fuer klinische Radiologie, Klinikum der Universitaet Muenchen, Grosshadern, Marchioninistrasse 15, 81377, Muenchen (Germany); Ertl-Wagner, B.; Reiser, M.F. [Institut fuer Klinische Radiologie, Klinikum der Universitaet Muenchen, Grosshadern, Muenchen (Germany)

    2003-11-01

    The corpus callosum is formed between the 7th and the 20th gestational week. If this process is disrupted, partial or complete callosal agenesis may ensue. As large parts of the supra- and infratentorial brain are created druing this critical period, associated anomalies need always to be searched for when callosal agenesis is present. Associations with neuro-genetic syndromes also exist. The corpus callosum is generally formed from front to back (''front-to-back rule''). Therefore, a partial callosal agenesis usually involves the posterior portion of the corpus callosum, while a secondary lesion of the corpus callosum does not follow this rule. Holoprosencephalies are a notable exception to this rule, as the frontal part of the corpus callosum is absent in spite of their classification as congenital malformations. They represent a disturbance of the differentiation and cleavage of the prosencephalon with a disruption of the separation of the cerebral hemispheres. Holoprosencephalies can be due to genetic causes, but also to intrauterine infections or other teratogenic causes. The holoprosencephalies are subdivided into alobar, semilobar and lobar holoprosencephalies. This article aims to describe the most important features of callosal agenesis and holoprosencephalies highlighting the respective imaging characteristics. (orig.) [German] Die Anlage des Balkens findet in der 7.-20. Woche nach Gestation statt. Stoerungen in dieser Entwicklungsphase koennen zu einer Balkenagenesie oder zu einer Balkenhypogenesie fuehren. Da in diesem Entwicklungsstadium grosse Anteile des Gross- und Kleinhirns angelegt werden, muss immer nach assoziierten Anlagestoerungen gesucht werden. Ebenso treten auch Kombinationen mit genetisch bedingten Syndromen auf. Die Entwicklung des Balkens folgt der sog. anterioren-posterioren Sequenz (''front-to-back rule''). Sekundaere Schaedigungen bei der Balkenentwicklung folgen dieser Regel nicht, und lassen

  12. Rubinstein-Taybi syndrome with agenesis of corpus callosum.

    Science.gov (United States)

    Mishra, Shubhankar; Agarwalla, Sunil Kumar; Potpalle, Dnyaneshwar Ramesh; Dash, Nishant Nilotpal

    2015-01-01

    Rubinstein-Taybi syndrome (RSTS) is a rare genetic disorder with characteristic morphological anomaly. Our patient was a 4.5-year-old girl came with features like broad thumbs, downward slanting palpebral fissures and mental retardation. Systemic abnormalities such as repeated infection, seizure with developmental delay were also associated with it. She was having head banging behavior abnormal slurring speech, incoordination while transferring things from one hand to other. Galaxy of clinical pictures and magnetic resonance imaging report helped to clinch the diagnosis as a case of "RSTS with corpus callosal agenesis" which to the best of our knowledge has never been reported in past from India.

  13. Rubinstein-Taybi syndrome with agenesis of corpus callosum

    Directory of Open Access Journals (Sweden)

    Shubhankar Mishra

    2015-01-01

    Full Text Available Rubinstein-Taybi syndrome (RSTS is a rare genetic disorder with characteristic morphological anomaly. Our patient was a 4.5-year-old girl came with features like broad thumbs, downward slanting palpebral fissures and mental retardation. Systemic abnormalities such as repeated infection, seizure with developmental delay were also associated with it. She was having head banging behavior abnormal slurring speech, incoordination while transferring things from one hand to other. Galaxy of clinical pictures and magnetic resonance imaging report helped to clinch the diagnosis as a case of "RSTS with corpus callosal agenesis" which to the best of our knowledge has never been reported in past from India.

  14. The Crossed Projection to the Striatum in Two Species of Monkey and in Humans: Behavioral and Evolutionary Significance

    DEFF Research Database (Denmark)

    Innocenti, Giorgio M.; Dyrby, Tim Bjørn; Andersen, Kasper Winther

    2016-01-01

    The corpus callosum establishes the anatomical continuity between the 2 hemispheres and coordinates their activity. Using histological tracing, single axon reconstructions, and diffusion tractography, we describe a callosal projection to n caudatus and putamen in monkeys and humans. In both species......, the origin of this projection is more restricted than that of the ipsilateral projection. In monkeys, it consists of thin axons (0.4–0.6 µm), appropriate for spatial and temporal dispersion of subliminal inputs. For prefrontal cortex, contralateral minus ipsilateral delays to striatum calculated from axon...... diameters and conduction distance are monkey and, by extrapolation,

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

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    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.

  16. A critical re-examination of sexual dimorphism in the corpus callosum microstructure

    DEFF Research Database (Denmark)

    Westerhausen, René; Kompus, Kristiina; Dramsdahl, Margaretha

    2011-01-01

    Recent diffusion-tensor imaging (DTI) studies suggest sexual dimorphism in the micro-structural architecture of the corpus callosum. However, the corpus callosum is also found to be larger in males than in females, a fact that might introduce a systematic bias to the analysis of DTI parameters. D...... the diffusion parameters did not correlate with regional callosal size. The present results indicate a stronger inter-hemispheric connectivity between the frontal lobes in males than females, which might be related to sex differences in hemispheric asymmetry and brain size....

  17. Reference: 175 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available T-DNA-tagged ibs mutants. Mutant ibs1 is affected in a cyclin-dependent kinase-like protein, and ibs2 is de...fective in AtSAC1b encoding a polyphosphoinositide phosphatase. Mutant ibs3 is affected in the regulation of...A)-dependent trailing necrosis, mutants ibs2 and ibs3 were affected in the priming for callose deposition. O...d tolerance to salt, which correlated with an affected priming for ABA-inducible gene expression. For all th

  18. 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

  19. Ultrastructural and metabolic transformations of differentiating Hyacinthus orientalis L, pollen grain cells. I. RNA and protein synthesis

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    Elżbieta Bednarska

    2014-01-01

    Full Text Available RNA and protein synthesis were investigated in generative and vegetative cells during maturation of pollen grains. The rate of RNA and protein synthesis was analysed in reference to the successive interphase periods of the life cycle of pollen cells as well as against the background of the growth dynamics of the cell volume. The results of studies demonstrated that the pollen grain increases in size owing to the growth of the vegetative cell. The generative one does not grow. RNA synthesis and that of proteins in differentiating pollen cells has a different course. In the growing vegetative cell it lasts longer and is more intensive than in the generative cell which does not grow. RNA and protein synthesis in the vegetative cell take place in the period from the callose stage to the stage of lemon-shaped generative cell, that is in the period of phases G1, S and G2. This synthesis is positively correlated with the growth of the pollen grain. RNA and protein synthesis in the generative cell comprises the period from the callose-less lenticular stage to the stage of spherical generative cell, that is the phases S and early phase G2. These results suggest that in the vegetative cell RNA and protein synthesis is utilised above all to increase of its cell, instead in non growing generative cell protein synthese is probably limited mostly to a histones and enzymatic proteins serving for the DNA replication process.

  20. 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.

  1. Functional topography of the corpus callosum investigated by DTI and f MRI

    Institute of Scientific and Technical Information of China (English)

    Mara; Fabri; Chiara; Pierpaoli; Paolo; Barbaresi; Gabriele; Polonara

    2014-01-01

    This short review examines the most recent functional studies of the topographic organization of the human corpus callosum, the main interhemispheric commissure. After a brief description of its anatomy, development, microstructure, and function, it examines and discusses the latest findings obtained using diffusion tensor imaging(DTI) and tractography(DTT) and functional magnetic resonance imaging(f MRI), three recently developed imaging techniques that have significantly expanded and refined our knowledge of the commissure. While DTI and DTT have been providing insights into its microstructure, integrity and level of myelination, f MRI has been the key technique in documenting the activation of white matter fibers, particularly in the corpus callosum. By combining DTT and f MRI it has been possible to describe the trajectory of the callosal fibers interconnecting the primary olfactory, gustatory, motor, somatic sensory, auditory and visual cortices at sites where the activation elicited by peripheral stimulation was detected by fMRI. These studies have demonstrated the presence of callosal fiber tracts that cross the commissure at the level of the genu, body, and splenium, at sites showing f MRI activation. Altogether such findings lend further support to the notion that the corpus callosum displays a functional topographic organization that can be explored with f MRI.

  2. 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.

  3. [A case of multiple sclerosis with alien hand (diagonistic dyspraxia)].

    Science.gov (United States)

    Konagaya, Masaaki; Sakai, Motoko

    2007-05-01

    In this paper, we describe a case of mutiple sclerosis (MS) with diagonistic dyspraxia and the callosal lesions in MRI. The patient was a 54-year-old woman with 12 year-history of suffering from MS. Her clinical symptoms were left alien hand, mild euphoria, right blindness, left visual deficit (0.06), mild weakness of right upper limb, complete paraplegia of lower limbs, total sensory deficit below middle sternal level and neurogenic bladder. She was right-handed person and her alien hand was such a manner; when she intended to use spoon with right hand, her left hand aimlessly began to hold and release a cup or dish. Then, she was diagnosed as diagnostic dyspraxia. Neuropsychological examinations disclosed left hemispheric dysfunction including left hand agraphia and disconnection of the callosum. MRI showed patchy lesions in the callosum, right optic radiation, both side thalamus (left > right), left cerebral peduncle, and spinal cord of cervical to the thoracal portion. Although the functional disorders and the radiological atrophy of the callosum, the clinical manifestation of the callosal disconnection in MS cases has been scarcely reported, and this case seems to be a quite rare condition to be described.

  4. Agroinfiltration reduces ABA levels and suppresses Pseudomonas syringae-elicited salicylic acid production in Nicotiana tabacum.

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    Arantza Rico

    Full Text Available BACKGROUND: Agrobacterium tumefaciens strain GV3101 (pMP90 is widely used in transient gene expression assays, including assays to study pathogen effectors and plant disease resistance mechanisms. However, inoculation of A. tumefaciens GV3101 into Nicotiana tabacum (tobacco leaves prior to infiltration with pathogenic and non-host strains of Pseudomonas syringae results in suppression of macroscopic symptoms when compared with leaves pre-treated with a buffer control. METHODOLOGY/FINDINGS: To gain further insight into the mechanistic basis of symptom suppression by A. tumefaciens we examined the effect of pre-treatment with A. tumefaciens on the growth of P. syringae, the production of the plant signalling molecules salicylic acid (SA and abscisic acid (ABA, and the presence of callose deposits. Pre-treatment with A. tumefaciens reduced ABA levels, P. syringae multiplication and P. syringae-elicited SA and ABA production, but promoted increased callose deposition. However, pre-treatment with A. tumefaciens did not suppress necrosis or SA production in leaves inoculated with the elicitor HrpZ. CONCLUSIONS/SIGNIFICANCE: Collectively, these results show that inoculation of N. tabacum leaves with A. tumefaciens alters plant hormone levels and plant defence responses to P. syringae, and demonstrate that researchers should consider the impact of A. tumefaciens on plant signal transduction when using A. tumefaciens-mediated transient expression assays to investigate ABA-regulated processes or pathogenicity and plant defence mechanisms.

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

    Science.gov (United States)

    Runavot, Jean-Luc; Guo, Xiaoyuan; Willats, William G T; Knox, J Paul; Goubet, Florence; Meulewaeter, Frank

    2014-01-01

    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.

  6. 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.

  7. Long-term depression and associativity in rat primary motor cortex following thalamic stimulation.

    Science.gov (United States)

    Eckert, M J; Racine, R J

    2006-12-01

    Associativity is an attractive property of LTP in terms of its possible mechanism as a model for memory storage. In this study, we compare the effects of homosynaptic vs. associative stimulation on the induction of LTP and LTD in the neocortex of freely behaving rats. Using a callosal input to the motor cortex as a 'strong' input (one that potentiates reliably following homosynaptic stimulation), we paired activity of this pathway with a 'weak' thalamocortical pathway (one that does not potentiate when stimulated homosynaptically). Surprisingly, homosynaptic HFS caused a lasting depression of the field EPSP in the thalamocortical pathway. Analysis of this effect revealed that it was largely polysynaptic. Associative HFS (HFS applied to both pathways) not only failed to induce an LTP effect in the thalamocortical pathway, it increased the magnitude of the depression. Associative HFS did, however, facilitate LTP induction in the 'strong' callosal pathway. When comparing the effects of homosynaptic and associative LTD induction (HFS on one pathway anticorrelated with LFS on the other), we found that both protocols induced a similar magnitude of depression. These results show that HFS applied to the thalamocortical pathway causes a depression and this depression is enhanced, not reversed, by associative pairing with a strong input.

  8. Mutation of a Gene in the Fungus Leptosphaeria maculans Allows Increased Frequency of Penetration of Stomatal Apertures of Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Candace E. Elliott; Harjono; Barbara J. Howlett

    2008-01-01

    Leptosphaeria maculans, a pathogen of Brassica napus, is unable to invade most wild-type accessions of Arabidopsis thaliana, although several mutants are susceptible. The infection pathway of L. maculans via a non-invasive inoculation method on A, thaliana Ires1 (undefined), pmr4-1 (defective in callose deposition), and pen1-1 and pen2-1 (defective in non-host responses to several pathogens) mutants is described. On wild types Col-0 and Ler-0, hyphae are generally arrested at stomatal apertures. A T-DNA insertional mutant of L. maculans (A22) that penetrates stomatal apertures of Col-0 and Ler-0 five to seven times more often than the wild-type isolate is described. The higher penetration frequency of isolate A22 is associated with an increased hypersensitive response, which includes callose deposition. Complementation analysis showed that the phenotype of this isolate is due to T-DNA insertion in an intronless gene denoted as ipa (increased penetration on Arabidopsis). This gene is predicted to encode a protein of 702 amino acids with best matches to hypothetical proteins in other filamentous ascomycetes. The ipa gene is expressed in the wild-type isolate at low levels in culture and during infection of A. thaliana and B. napus.

  9. Agenesis of the corpus callosum. An autopsy study in fetuses.

    Science.gov (United States)

    Kidron, Debora; Shapira, Daniel; Ben Sira, Liat; Malinger, Gustavo; Lev, Dorit; Cioca, Andreea; Sharony, Reuven; Lerman Sagie, Tally

    2016-02-01

    Agenesis of the corpus callosum is currently diagnosed prenatally with ultrasound and MRI. While the diagnostic aspects of callosal defects are widely addressed, anatomo-histological data from fetal autopsies are sparse. Callosal defects were present in 50 fetal autopsies. Four distinct groups of complete, partial, hypoplastic, and mixed defects were determined by the gross and histologic details of the corpus callosum. These details helped to rule out other midline defects such as holoprosencephaly. Additional autopsy findings enabled specific diagnoses and suggested etiopathogeneses. Hypoplastic and mixed defects were associated with more abnormalities of the cerebral hemispheres and internal organs. The four groups did not differ according to gender, external dysmorphism, or cerebellar and brainstem anomalies. Defects were classified as syndromic (68 %), encephaloclastic (8 %), undetermined (14 %), or isolated (10 %) based on the autopsy findings. Isolated agenesis of the corpus callosum was diagnosed in only 10 % of the cases in this series, compared to higher numbers diagnosed by prenatal ultrasonography and MRI. Therefore, the autopsy, through its detailed, careful evaluation of external, as well as gross and histological internal features, can elucidate the etiopathogenesis of agenesis of the corpus callosum and suggest specific diagnoses which cannot be ascertained by prenatal imaging.

  10. Intrahemispheric dysfunction in primary motor cortex without corpus callosum: a transcranial magnetic stimulation study

    Directory of Open Access Journals (Sweden)

    Lassonde Maryse

    2006-06-01

    Full Text Available Abstract Background The two human cerebral hemispheres are continuously interacting, through excitatory and inhibitory influences and one critical structure subserving this interhemispheric balance is the corpus callosum. Interhemispheric neurophysiological abnormalities and intrahemispheric behavioral impairments have been reported in individuals lacking the corpus callosum. The aim of this study was to examine intrahemispheric neurophysiological function in primary motor cortex devoid of callosal projections. Methods Intracortical excitatory and inhibitory systems were tested in three individuals with complete agenesis of the corpus callosum and sixteen healthy individuals. These systems were assessed using transcranial magnetic stimulation (TMS protocols: motor threshold at rest, paired-pulse curve, and cortical silent period. Results TMS revealed no difference between the patient and control groups on the motor threshold measure, as well as intracortical facilitation and intracortical inhibition systems as tested by paired stimulation. However, intrahemispheric inhibitory function was found to be abnormal in participants without callosal projections, as the cortical silent period duration was significantly increased in the patient group. Conclusion These data suggest that in addition to previously reported impaired interhemispheric function, patients lacking the entire corpus callosum also display abnormal intrahemispheric excitability of the primary motor cortex.

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

    Indian Academy of Sciences (India)

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

    2012-12-01

    We correlated root growth inhibition with aluminium (Al3+) localization and toxicity symptoms in rice roots using seedlings of two genotypes (tolerant and sensitive) that were exposed to different AlCl3 concentrations. Al3+ 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$\\to$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. Morin staining showed the presence of Al3+ 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, Al3+ 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 Al3+ stress. Moreover, Al3+-induced callose accumulation was a late response occurring in the same areas where Al3+ was present.

  12. Plasmodesmata in Arabidopsis thaliana suspension cells.

    Science.gov (United States)

    Bayer, E; Thomas, C L; Maule, A J

    2004-06-01

    A current challenge in plant biology is to identify the structural and functional components of plasmodesmata (PDs). The use of plant tissue as a source material for plasmodesmal characterisation has had limited success, so we have explored the frequency and features of PDs occurring in suspension cell cultures of Arabidopsis thaliana. This material has the advantages of homogeneity, quantity, and ease of disruption. Using light and electron microscopy and immunostaining for callose and calreticulin, we showed that suspension cells laid down abundant PDs in division walls, and that vestiges of these structures were retained as half PDs even when the cell-to-cell contacts were disrupted during culture growth. Although callose was a reliable marker for PD distribution, which was deposited in an organised collar around the neck of PDs, it was not abundant in unstressed cells. Calreticulin and the chemical stain 3,3'-dihexyloxacarbocyanine iodide also provided useful markers when monitoring PDs in cell wall preparations by light microscopy. Purified cell walls were shown to be virtually free of contamination from cytoplasmic components, except for the presence of small amounts of cortical endoplasmic reticulum attached to PDs. Hence, clean cell walls from A. thaliana suspension cells provide a valuable resource for a proteomic approach to the analysis of plasmodesmal components.

  13. 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 × 10(7) 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.

  14. 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.

  15. 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

  16. Corpus callosum size and diffusion tensor anisotropy in adolescents and adults with schizophrenia.

    Science.gov (United States)

    Balevich, Emily C; Haznedar, M Mehmet; Wang, Eugene; Newmark, Randall E; Bloom, Rachel; Schneiderman, Jason S; Aronowitz, Jonathan; Tang, Cheuk Y; Chu, King-Wai; Byne, William; Buchsbaum, Monte S; Hazlett, Erin A

    2015-03-30

    The corpus callosum has been implicated as a region of dysfunctional connectivity in schizophrenia, but the association between age and callosal pathology is unclear. Magnetic resonance imaging (MRI) and diffusion-tensor imaging (DTI) were performed on adults (n=34) and adolescents (n=17) with schizophrenia and adult (n=33) and adolescent (n=15) age- and sex-matched healthy controls. The corpus callosum was manually traced on each participant׳s MRI, and the DTI scan was co-registered to the MRI. The corpus callosum was divided into five anteroposterior segments. Area and anisotropy were calculated for each segment. Both patient groups demonstrated reduced callosal anisotropy; however, the adolescents exhibited reductions mostly in anterior regions while the reductions were more prominent in posterior regions of the adults. The adolescent patients showed greater decreases in absolute area as compared with the adult patients, particularly in the anterior segments. However, the adults showed greater reductions when area was considered relative to whole brain white matter volume. Our results suggest that the initial stages of the illness are characterized by deficiencies in frontal connections, and the chronic phase is characterized by deficits in the posterior corpus callosum; or, alternatively, adolescent-onset schizophrenia may represent a different or more severe form of the illness.

  17. HrpNEa -induced deterrent effect on phloem feeding of the green peach aphid Myzus persicae requires AtGSL5 and AtMYB44 genes in Arabidopsis thaliana

    Indian Academy of Sciences (India)

    Beibei Lü; Weiwei Sun; Shuping Zhang; Chunling Zhang; Jun Qian; Xiaomeng Wang; Rong Gao; Hansong Dong

    2011-03-01

    In Arabidopsis thaliana (Arabidopsis) treated with the harpin protein HrpNEa, resistance to the green peach aphid Myzus persicae, a generalist phloem-feeding insect, develops with induced expression of the AtMYB44 gene. Special GLUCAN SYNTHESIS-LIKE (GSL) genes and -1,3-glucan callose play an important role in plant defence responses to attacks by phloem-feeding insects. Here we report that AtGLS5 and AtMYB44 are both required for HrpNEa-induced repression of M. persicae feeding from the phloem of Arabidopsis leaves. In 24 h successive surveys on large-scale aphid populations, the proportion of feeding aphids was much smaller in HrpNEa-treated plants than in control plants, and aphids preferred to feed from the 37 tested atgsl mutants rather than the wild-type plant. The atgsl mutants were generated previously by mutagenesis in 12 identified AtGSL genes (AtGSL1 through AtGSL12); in the 24 h survey, both atgsl5 and atgsl6 tolerated aphid feeding, and atgsl5 was the most tolerant. Consistently, atgsl5 was also most inhibitive to the deterrent effect of HrpNEa on the phloem-feeding activity of aphids as monitored by the electrical penetration graph technique. These results suggested an important role of the AtGSL5 gene in the effect of HrpNEa. In response to HrpNEa, AtGSL5 expression and callose deposition were induced in the wild-type plant but not in atgsl5. In response to HrpNEa, moreover, the AtMYB44 gene known to be required for repression of aphid reproduction on the plant was also required for repression of the phloem-feeding activity. Small amounts of the AtGSL5 transcript and callose deposition were detected in the atmyb44 mutant, as in atgsl5. Both mutants performed similarly in tolerating the phloem-feeding activity and impairing the deterrent effect of HrpNEa, suggesting that AtGSL5 and AtMYB44 both contributed to the effect.

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

    Directory of Open Access Journals (Sweden)

    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. The Structure of Sucrose Synthase-1 from Arabidopsis thaliana and Its Functional Implications

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yi; Anderson, Spencer; Zhang, Yanfeng; Garavito, R. Michael (MSU); (NWU)

    2014-10-02

    Sucrose transport is the central system for the allocation of carbon resources in vascular plants. During growth and development, plants control carbon distribution by coordinating sites of sucrose synthesis and cleavage in different plant organs and different cellular locations. Sucrose synthase, which reversibly catalyzes sucrose synthesis and cleavage, provides a direct and reversible means to regulate sucrose flux. Depending on the metabolic environment, sucrose synthase alters its cellular location to participate in cellulose, callose, and starch biosynthesis through its interactions with membranes, organelles, and cytoskeletal actin. The x-ray crystal structure of sucrose synthase isoform 1 from Arabidopsis thaliana (AtSus1) has been determined as a complex with UDP-glucose and as a complex with UDP and fructose, at 2.8- and 2.85-{angstrom} resolutions, respectively. The AtSus1 structure provides insights into sucrose catalysis and cleavage, as well as the regulation of sucrose synthase and its interactions with cellular targets.

  20. [Results of fibrin clot application for acceleration of regeneration of the damaged mandible in experiment].

    Science.gov (United States)

    Maĭborodin, I V; Kolesnikov, I S; Shevela, A I; Sheplev, B V; Drovosekov, M N; Toder, M S

    2011-01-01

    The processes of regeneration of the damaged rat bottom jaw bone after application of enriched thrombocytes a fibrin clot were studied by morphological and radiovisiographic methods. At a natural course of regeneration the artificial aperture of bone was filled with blood and there the blood clot was formed. After 1 week the separate bone islets of a young tissue occurred in bone defect. In 2-3 weeks the aperture in a bottom jaw bone was completely closed by a young bone tissue. After operation with filling of bone bottom jaw defect by fibrin clot there was no formation of a blood clot. Already after 1 week the bone tissue defect was filled by the merged islets of again generated bone. By second week after fibrin use the further formation of bone tissue in defect and formation of a bone callosity was noted.

  1. Evidence of programmed cell death during microsporogenesis in an interspecific Brachiaria (Poaceae: Panicoideae: Paniceae) hybrid.

    Science.gov (United States)

    Fuzinatto, V A; Pagliarini, M S; Valle, C B

    2007-05-11

    Morphological changes have been investigated during plant programmed cell death (PCD) in the last few years due to the new interest in a possible apoptotic-like phenomenon existing in plants. Although PCD has been reported in several tissues and specialized cells in plants, there have been few reports of its occurrence during microsporogenesis. The present study reports a typical process of PCD during meiosis in an interspecific Brachiaria hybrid leading to male sterility. In this hybrid, some inflorescences initiated meiosis but it was arrested in zygotene/pachytene. From this stage, meiocytes underwent a severe alteration in shape showing substantial membrane blebbing; the cytoplasm became denser at the periphery; the cell nucleus entered a progressive stage of chromatin disintegration, and then the nucleolus disintegrated, and the cytoplasm condensed and shrunk. The oldest flowers of the raceme showed only the callose wall in the anthers showing obvious signs of complete sterility.

  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.

  3. Chitosan as a MAMP, searching for a PRR.

    Science.gov (United States)

    Iriti, Marcello; 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 Ca(2+), 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).

  4. Recessive mutations in EPG5 cause Vici syndrome, a multisystem disorder with defective autophagy

    Science.gov (United States)

    Cullup, Thomas; Kho, Ay L.; Dionisi-Vici, Carlo; Brandmeier, Birgit; Smith, Frances; Urry, Zoe; Simpson, Michael A.; Yau, Shu; Bertini, Enrico; McClelland, Verity; Al-Owain, Mohammed; Koelker, Stefan; Koerner, Christian; Hoffmann, Georg F.; Wijburg, Frits A.; Hoedt, Amber E. ten; Rogers, Curtis; Manchester, David; Miyata, Rie; Hayashi, Masaharu; Said, Elizabeth; Soler, Doriette; Kroisel, Peter M.; Windpassinger, Christian; Filloux, Francis M.; Al-Kaabi, Salwa; Hertecant, Jozef; Del Campo, Miguel; Buk, Stefan; Bodi, Istvan; Goebel, Hans-Hilmar; Sewry, Caroline A.; Abbs, Stephen; Mohammed, Shehla; Josifova, Dragana; Gautel, Mathias; Jungbluth, Heinz

    2012-01-01

    Vici syndrome is a recessively inherited multisystem disorder characterized by callosal agenesis, cataracts, cardiomyopathy, combined immunodeficiency and hypopigmentation. To investigate the molecular basis of Vici syndrome, we carried out exome and Sanger sequence analysis in a cohort of 18 patients. We identified recessive mutations in EPG5 (previously KIAA1632), indicating a causative role in Vici syndrome. EPG5 is the human homologue of the metazoan-specific autophagy gene epg-5, encoding a key autophagy regulator (ectopic P-granules autophagy protein 5) implicated in the formation of autolysosomes. Further studies demonstrated a severe block of autophagosomal clearance in muscle and fibroblasts from EPG5 mutant patients, resulting in autophagic cargo accumulation in autophagosomes. These findings indicate Vici syndrome as a paradigm of a human multisystem disorder associated with defective autophagy, and suggest a fundamental role of the autophagy pathway in the anatomical and functional formation of organs such as the brain, the heart and the immune system. PMID:23222957

  5. Plasticity and stability of the visual system in human achiasma.

    Science.gov (United States)

    Hoffmann, Michael B; Kaule, Falko R; Levin, Netta; Masuda, Yoichiro; Kumar, Anil; Gottlob, Irene; Horiguchi, Hiroshi; Dougherty, Robert F; Stadler, Joerg; Wolynski, Barbara; Speck, Oliver; Kanowski, Martin; Liao, Yaping J; Wandell, Brian A; Dumoulin, Serge O

    2012-08-09

    The absence of the optic chiasm is an extraordinary and extreme abnormality in the nervous system. The abnormality produces highly atypical functional responses in the cortex, including overlapping hemifield representations and bilateral population receptive fields in both striate and extrastriate visual cortex. Even in the presence of these large functional abnormalities, the effect on visual perception and daily life is not easily detected. Here, we demonstrate that in two achiasmic humans the gross topography of the geniculostriate and occipital callosal connections remains largely unaltered. We conclude that visual function is preserved by reorganization of intracortical connections instead of large-scale reorganizations of the visual cortex. Thus, developmental mechanisms of local wiring within cortical maps compensate for the improper gross wiring to preserve function in human achiasma.

  6. Hyperlexia and ambient echolalia in a case of cerebral infarction of the left anterior cingulate cortex and corpus callosum.

    Science.gov (United States)

    Suzuki, Tadashi; Itoh, Shouichi; Hayashi, Mototaka; Kouno, Masako; Takeda, Katsuhiko

    2009-10-01

    We report the case of a 69-year-old woman with cerebral infarction in the left anterior cingulate cortex and corpus callosum. She showed hyperlexia, which was a distinctive reading phenomenon, as well as ambient echolalia. Clinical features also included complex disorders such as visual groping, compulsive manipulation of tools, and callosal disconnection syndrome. She read words written on the cover of a book and repeated words emanating from unrelated conversations around her or from hospital announcements. The combination of these two features due to a focal lesion has never been reported previously. The supplementary motor area may control the execution of established subroutines according to external and internal inputs. Hyperlexia as well as the compulsive manipulation of tools could be interpreted as faulty inhibition of preexisting essentially intact motor subroutines by damage to the anterior cingulate cortex reciprocally interconnected with the supplementary motor area.

  7. 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.

  8. Paroxysmal posterior variant alien hand syndrome associated with parietal lobe infarction: case presentation.

    Science.gov (United States)

    Demiryürek, Bekir Enes; Gündogdu, Aslı Aksoy; Acar, Bilgehan Atılgan; Alagoz, Aybala Neslihan

    2016-10-01

    Alien hand syndrome (AHS) is an involuntary and rare neurological disorder emerges at upper extremity. AHS is a disconnection syndrome with the symptoms of losing sense of agency and sense of ownership, and presence of involuntary autonomic motor activity. There are frontal, callosal and posterior types of AHS and each of them occurs depend on the lesions of different of the brain. Posterior variant is a rarely encountered AHS type compared to others. AHS, generally regarded as persistent, but rarely maybe observed as paroxysmal. In this article, we present 71 year old patient with right posterior parietal lobe infarction and developed posterior variant AHS on left arm 1 month after discharge from the hospital. To discriminate AHS from conditions such as extrapyramidal movement disorders and epileptic seizures that take part in differential diagnosis should be kept in mind by the clinicians. Wrong and unnecessary treatments could be prevented in this way.

  9. 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. PMID:25745324

  10. 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.

  11. Síndrome de Aicardi: relato de caso Aicardi syndrome: case report

    Directory of Open Access Journals (Sweden)

    José Alexandre Bastos

    2001-06-01

    Full Text Available Relatamos um caso de síndrome de Aicardi completa em criança do sexo feminino de 2 meses de idade com defeitos lacunares da coróide, espasmos em flexão, agenesia de corpo caloso e alterações eletrencefalográficas do tipo hipsarritmia assimétrica e alterna atendida no Serviço de Neuropediatria e Neurofisiologia clínica do Hospital de Base de São José do Rio Preto, SP .We report a case of Aicardi syndrome in a female child with 2 month old, ocular abnormalities "chorioretinal lacunae", flexion in spasms, hipsarrhythmic "split brain", callosal agenesis refered to Service of Neuropediatric and Neurophysiology of Base Hospital of São José do Rio Preto, SP, Brazil.

  12. Aicardi syndrome: A report of five Indian cases

    Directory of Open Access Journals (Sweden)

    Banerjee T

    2006-01-01

    Full Text Available Five Indian cases of Aicardi syndrome, aged 1-13 years and all with the classic triad of infantile spasm, corpus callosal agenesis and chorioretinal lacunae, were presented. The purpose of this report was to demonstrate the clinical, electroencephalographic (EEG and radiological spectrum and the treatment outcome of this disorder among the Indians. None of the patient had any family history of similar illness. All had profound psychomotor impairment with no meaningful speech development. There were microphthalmia in 2, optic disc coloboma in 1, interhemispheric cyst in 1, periventricular heterotopia in 2 and thoracolumbar kyphoscoliosis in 2 cases. They all had early onset epilepsy and there were multiple types of seizures. Two cases (40% had the characteristic dissociated burst-suppression pattern in EEG. Two cases whose antiepileptic medications included vigabatrin had complete control of seizure.

  13. Cranial MRI in the Nijmegen breakage syndrome

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  14. 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.

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

    Science.gov (United States)

    Singh, Akanksha; Gupta, Rupali; Pandey, Rakesh

    2016-01-01

    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.

  16. Pattern recognition on brain magnetic resonance imaging in alpha dystroglycanopathies

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    Bindu Parayil

    2010-01-01

    Full Text Available Alpha dystroglycanopathies are heterogeneous group of disorders both phenotypically and genetically. A subgroup of these patients has characteristic brain imaging findings. Four patients with typical imaging findings of alpha dystroglycanopathy are reported. Phenotypic features included: global developmental delay, contractures, hypotonia and oculomotor abnormalities in all. Other manifestations were consanguinity (3, seizures (3, macrocephaly (1, microcephaly (3, retinal changes (2 and hypogenitalism (2. Magnetic resonance imaging (MRI of the brain revealed polymicrogyria, white matter changes, pontine hypoplasia, and subcortical cerebellar cysts in all the patients, ventriculomegaly, callosal abnormalities, and absent septum pellucidum in two and Dandy -Walker variant malformation in three. Magnetic resonace imaging of the first cousin of one the patient had the same characteristic imaging features. Brain imaging findings were almost identical despite heterogeneity in clinical presentation and histopathological features. Pattern recognition of MR imaging features may serve as a clue to the diagnosis of alpha dystroglycanopathy.

  17. Effect of lead on root growth.

    Science.gov (United States)

    Fahr, Mouna; Laplaze, Laurent; Bendaou, Najib; Hocher, Valerie; Mzibri, Mohamed El; Bogusz, Didier; Smouni, Abdelaziz

    2013-01-01

    Lead (Pb) is one of the most widespread heavy metal contaminant in soils. It is highly toxic to living organisms. 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 Pb 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 Pb 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.

  18. Diffusion tensor quantification and cognitive correlates of the macrostructure and microstructure of the corpus callosum in typically developing and dyslexic children.

    Science.gov (United States)

    Hasan, Khader M; Molfese, David L; Walimuni, Indika S; Stuebing, Karla K; Papanicolaou, Andrew C; Narayana, Ponnada A; Fletcher, Jack M

    2012-11-01

    Noninvasive quantitative MRI methods, such as diffusion tensor imaging (DTI), can offer insights into the structure-function relationships in human developmental brain disorders. In this article, we quantified the macrostructural and microstructural attributes of the corpus callosum (CC) in children with dyslexia and in typically developing readers of comparable age and gender. Diffusion anisotropy, and mean, radial and axial diffusivities of cross-sectional CC subregions were computed using a validated DTI methodology. The normalized posterior CC area was enlarged in children with dyslexia relative to that in typically developing children. Moreover, the callosal microstructural attributes, such as the mean diffusivity of the posterior middle sector of the CC, correlated significantly with measures of word reading and reading comprehension. Reading group differences in fractional anisotropy, mean diffusivity and radial diffusivity were observed in the posterior CC (CC5). This study demonstrates the utility of regional DTI measurements of the CC in understanding the neurobiology of reading disorders.

  19. Pollen tube branching in the ovary of five species of Oenothera

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    Renata Śnieżko

    2014-02-01

    Full Text Available Flowers of Oenothera hookeri Torr. et Gray, Oe. brevistylis and Oe. lamarkiana de Vries were pollinated after anthesis by insects. Oe. biennis L., Oe. suaveolens Desf and sulfurea were selfpollinated in the buds. Pollen morphology was slightly different: Oe. hookeri have regular, triporated pollen, often germinating through two pores; in Oe. suaveolens many pollen grains had callose patches on the intine; in Oe. brevistylis tetraporated pollen were more often than in other species; in Oe. lamarckiana many pollen grains were empty; in Oe. biennis and Oe. suaveolens pollen grain size and viability varied. The pollen tube growth and fertilization were similar in 5 species and can be considered as typical for Oenothera. In the ovary pollen tubes branched and changed their growth direction. Near micropyle they formed short branches to the inner integument. In the nucellus the pollen tube became swollen.

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

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    Banshi Lal Kumawat

    2015-01-01

    Full Text Available 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.

  1. Musical expertise affects neural bases of letter recognition.

    Science.gov (United States)

    Proverbio, Alice Mado; Manfredi, Mirella; Zani, Alberto; Adorni, Roberta

    2013-02-01

    It is known that early music learning (playing of an instrument) modifies functional brain structure (both white and gray matter) and connectivity, especially callosal transfer, motor control/coordination and auditory processing. We compared visual processing of notes and words in 15 professional musicians and 15 controls by recording their synchronized bioelectrical activity (ERPs) in response to words and notes. We found that musical training in childhood (from age ~8 years) modifies neural mechanisms of word reading, whatever the genetic predisposition, which was unknown. While letter processing was strongly left-lateralized in controls, the fusiform (BA37) and inferior occipital gyri (BA18) were activated in both hemispheres in musicians for both word and music processing. The evidence that the neural mechanism of letter processing differed in musicians and controls (being absolutely bilateral in musicians) suggests that musical expertise modifies the neural mechanisms of letter reading.

  2. Up-regulation of HP1γ expression during neuronal maturation promotes axonal and dendritic development in mouse embryonic neocortex.

    Science.gov (United States)

    Oshiro, Hiroaki; Hirabayashi, Yusuke; Furuta, Yasuhide; Okabe, Shigeo; Gotoh, Yukiko

    2015-02-01

    Immature neurons undergo morphological and physiological changes including axonal and dendritic development to establish neuronal networks. As the transcriptional status changes at a large number of genes during neuronal maturation, global changes in chromatin modifiers may take place in this process. We now show that the amount of heterochromatin protein 1γ (HP1γ) increases during neuronal maturation in the mouse neocortex. Knockdown of HP1γ suppressed axonal and dendritic development in mouse embryonic neocortical neurons in culture, and either knockdown or knockout of HP1γ impaired the projection of callosal axons of superficial layer neurons to the contralateral hemisphere in the developing neocortex. Conversely, forced expression of HP1γ facilitated axonal and dendritic development, suggesting that the increase of HP1γ is a rate limiting step in neuronal maturation. These results together show an important role for HP1γ in promoting axonal and dendritic development in maturing neurons.

  3. 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

  4. Early anisotropy changes in the corpus callosum of patients with optic neuritis

    Energy Technology Data Exchange (ETDEWEB)

    Bester, M.; Ding, X.Q.; Holst, B.; Fiehler, J. [University Medical Center Hamburg-Eppendorf, Department of Neuroradiology, Hamburg (Germany); Heesen, C.; Schippling, S.; Martin, R. [University Medical Center Hamburg-Eppendorf, Department of Neuroradiology, Hamburg (Germany); University Medical Center Hamburg-Eppendorf, Institute for Neuroimmunology and Clinical MS Research, Hamburg (Germany)

    2008-07-15

    Optic neuritis (ON) and any other early manifestation of multiple sclerosis (MS) are referred to as clinically isolated syndrome (CIS) as long as MS is suspected. In this prospective study we aimed to determine whether diffusion tensor imaging (DTI) could quantify structural changes in patients with early MS. A total of 24 patients and 15 control subjects were prospectively followed by clinical examinations and MRI. the main inclusion criterion was presentation with ON. Patients underwent serial MRI scans: MRI1 (baseline, n=24), MRI2 (mean 6.6 months, n=24), MRI3 (mean 13.0 months, n=14), MRI4 (mean 39.4 months, n=5). Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps were derived from DTI. Four regions of interest (ROIs) were defined in normal-appearing white matter (NAWM). In the temporal course FA decreased in the genu of the callosal body (GCC) from MRI1 to MRI4 (P=0.005) and in the splenium of the callosal body (SCC) (P=0.006). Patients already had lower FA values in the SCC (P<0.01) on MRI1 compared with the controls. Patients had lower FA values in the GCC (P<0.01) starting from MRI2. Patients with definite MS on follow-up (n=9) showed a correlation between FA in the SCC and time (r=-0.40, P=0.004), whereas patients without progression did not. Our findings suggest that the corpus callosum is an early site for development of anisotropy changes in MS patients with ON. There seems to be a primary FA decrease in all patients with ON that only deteriorates in the group developing definite MS. (orig.)

  5. Erwinia amylovora type three-secreted proteins trigger cell death and defense responses in Arabidopsis thaliana.

    Science.gov (United States)

    Degrave, A; Fagard, M; Perino, C; Brisset, M N; Gaubert, S; Laroche, S; Patrit, O; Barny, M-A

    2008-08-01

    Erwinia amylovora is the bacterium responsible for fire blight, a necrotic disease affecting plants of the rosaceous family. E. amylovora pathogenicity requires a functional type three secretion system (T3SS). We show here that E. amylovora triggers a T3SS-dependent cell death on Arabidopsis thaliana. The plants respond by inducing T3SS-dependent defense responses, including salicylic acid (SA)-independent callose deposition, activation of the SA defense pathway, reactive oxygen species (ROS) accumulation, and part of the jasmonic acid/ethylene defense pathway. Several of these reactions are similar to what is observed in host plants. We show that the cell death triggered by E. amylovora on A. thaliana could not be simply explained by the recognition of AvrRpt2 ea by the resistance gene product RPS2. We then analyzed the role of type three-secreted proteins (T3SPs) DspA/E, HrpN, and HrpW in the induction of cell death and defense reactions in A. thaliana following infection with the corresponding E. amylovora mutant strains. HrpN and DspA/E were found to play an important role in the induction of cell death, activation of defense pathways, and ROS accumulation. None of the T3SPs tested played a major role in the induction of SA-independent callose deposition. The relative importance of T3SPs in A. thaliana is correlated with their relative importance in the disease process on host plants, indicating that A. thaliana can be used as a model to study their role.

  6. 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.

  7. Truncated Cables1 causes agenesis of the corpus callosum in mice.

    Science.gov (United States)

    Mizuno, Seiya; Tra, Dinh T H; Mizobuchi, Atsushi; Iseki, Hiroyoshi; Mizuno-Iijima, Saori; Kim, Jun-Dal; Ishida, Junji; Matsuda, Yoichi; Kunita, Satoshi; Fukamizu, Akiyoshi; Sugiyama, Fumihiro; Yagami, Ken-ichi

    2014-03-01

    Agenesis of the corpus callosum (ACC) is a congenital abnormality of the brain structure. More than 60 genes are known to be involved in corpus callosum development. However, the molecular mechanisms underlying ACC are not fully understood. Previously, we produced a novel transgenic mouse strain, TAS, carrying genes of the tetracycline-inducible expression system that are not involved in brain development, and inherited ACC was observed in the brains of all homozygous TAS mice. Although ACC was probably induced by transgene insertion mutation, the causative gene and the molecular mechanism of its pathogenesis remain unclear. Here, we first performed interphase three-color fluorescence in situ hybridization (FISH) analysis to determine the genomic insertion site. Transgenes were inserted into chromosome 18 ∼12.0 Mb from the centromere. Gene expression analysis and genomic PCR walking showed that the genomic region containing exon 4 of Cables1 was deleted by transgene insertion and the other exons of Cables1 were intact. The mutant allele was designated as Cables1(TAS). Interestingly, Cables1(TAS) mRNA consisted of exons 1-3 of Cables1 and part of the transgene that encoded a novel truncated Cables1 protein. Homozygous TAS mice exhibited mRNA expression of Cables1(TAS) in the fetal cerebrum, but not that of wild-type Cables1. To investigate whether a dominant negative effect of Cables1(TAS) or complete loss of function of Cables1 gives rise to ACC, we produced Cables1-null mutant mice. ACC was not observed in Cables1-null mutant mice, suggesting that a dominant negative effect of Cables1(TAS) impairs callosal formation. Moreover, ACC frequency in Cables1(+/TAS) mice was significantly lower than that in Cables1(-/TAS) mice, indicating that wild-type Cables1 interfered with the dominant negative effect of Cables1(TAS). This study indicated that truncated Cables1 causes ACC and wild-type Cables1 contributes to callosal formation.

  8. Induction of host defences by Rhizobium during ineffective nodulation of pea (Pisum sativum L.) carrying symbiotically defective mutations sym40 (PsEFD), sym33 (PsIPD3/PsCYCLOPS) and sym42.

    Science.gov (United States)

    Ivanova, Kira A; Tsyganova, Anna V; Brewin, Nicholas J; Tikhonovich, Igor A; Tsyganov, Viktor E

    2015-11-01

    Rhizobia are able to establish a beneficial interaction with legumes by forming a new organ, called the symbiotic root nodule, which is a unique ecological niche for rhizobial nitrogen fixation. Rhizobial infection has many similarities with pathogenic infection and induction of defence responses accompanies both interactions, but defence responses are induced to a lesser extent during rhizobial infection. However, strong defence responses may result from incompatible interactions between legumes and rhizobia due to a mutation in either macro- or microsymbiont. The aim of this research was to analyse different plant defence reactions in response to Rhizobium infection for several pea (Pisum sativum) mutants that result in ineffective symbiosis. Pea mutants were examined by histochemical and immunocytochemical analyses, light, fluorescence and transmission electron microscopy and quantitative real-time PCR gene expression analysis. It was observed that mutations in pea symbiotic genes sym33 (PsIPD3/PsCYCLOPS encoding a transcriptional factor) and sym40 (PsEFD encoding a putative negative regulator of the cytokinin response) led to suberin depositions in ineffective nodules, and in the sym42 there were callose depositions in infection thread (IT) and host cell walls. The increase in deposition of unesterified pectin in IT walls was observed for mutants in the sym33 and sym42; for mutant in the sym42, unesterified pectin was also found around degrading bacteroids. In mutants in the genes sym33 and sym40, an increase in the expression level of a gene encoding peroxidase was observed. In the genes sym40 and sym42, an increase in the expression levels of genes encoding a marker of hypersensitive reaction and PR10 protein was demonstrated. Thus, a range of plant defence responses like suberisation, callose and unesterified pectin deposition as well as activation of defence genes can be triggered by different pea single mutations that cause perception of an otherwise

  9. 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.

  10. Polyamines and transglutaminase activity are involved in compatible and self-incompatible pollination of Citrus grandis.

    Science.gov (United States)

    Gentile, Alessandra; Antognoni, Fabiana; Iorio, Rosa Anna; Distefano, Gaetano; Las Casas, Giuseppina; La Malfa, Stefano; Serafini-Fracassini, Donatella; Del Duca, Stefano

    2012-02-01

    Pollination of pummelo (Citrus grandis L. Osbeck) pistils has been studied in planta by adding compatible and self-incompatible (SI) pollen to the stigma surface. The pollen germination has been monitored inside the pistil by fluorescent microscopy showing SI altered morphologies with irregular depositions of callose in the tube walls, and heavy callose depositions in enlarged tips. The polyamine (PA) content as free, perchloric acid (PCA)-soluble and -insoluble fractions and transglutaminase (TGase) activity have been analyzed in order to deepen their possible involvement in the progamic phase of plant reproduction. The conjugated PAs in PCA-soluble fraction were definitely higher than the free and the PCA-insoluble forms, in both compatible and SI pollinated pistils. In pistils, pollination caused an early decrease of free PAs and increase of the bound forms. The SI pollination, showed highest values of PCA-soluble and -insoluble PAs with a maximum in concomitance with the pollen tube arrest. As TGase mediates some of the effects of PAs by covalently binding them to proteins, its activity, never checked before in Citrus, was examined with two different assays. In addition, the presence of glutamyl-PAs confirmed the enzyme assay data and excluded the possibility of a misinterpretation. The SI pollination caused an increase in TGase activity, whereas the compatible pollination caused its decrease. Similarly to bound PAs, the glutamyl-PAs and the enzyme activity peaked in the SI pollinated pistils in concomitance with the observed block of the pollen tube growth, suggesting an involvement of TGase in SI response.

  11. Ethylene and Abscisic Acid Signaling Pathways Differentially Influence Tomato Resistance to Combined Powdery Mildew and Salt Stress

    Science.gov (United States)

    Kissoudis, Christos; Seifi, Alireza; Yan, Zhe; Islam, A. T. M. Tanjimul; van der Schoot, Hanneke; van de Wiel, Clemens C. M.; Visser, Richard G. F.; van der Linden, C. G.; Bai, Yuling

    2017-01-01

    There is currently limited knowledge on the role of hormones in plants responses to combinations of abiotic and pathogen stress factors. This study focused on the response of tomato near-isogenic lines (NILs) that carry the Ol-1, ol-2, and Ol-4 loci, conferring resistance to tomato powdery mildew (PM) caused by Oidium neolycopersici, to combined PM and salt stress. These NILs were crossed with the notabilis (ABA-deficient), defenceless1 (JA-deficient), and epinastic (ET overproducer) tomato mutants to investigate possible roles of hormone signaling in response to combined stresses. In the NILs, marker genes for hormonal pathways showed differential expression patterns upon PM infection. The epinastic mutation resulted in breakdown of resistance in NIL-Ol-1 and NIL-ol-2. This was accompanied by reduced callose deposition, and was more pronounced under combined salt stress. The notabilis mutation resulted in H2O2 overproduction and reduced susceptibility to PM in NIL-Ol-1 under combined stress, but lead to higher plant growth reduction under salinity and combined stress. Resistance in NIL-ol-2 was compromised by the notabilis mutation, which was potentially caused by reduction of callose deposition. Under combined stress the compromised resistance in NIL-ol-2 was restored. PM resistance in NIL-Ol-4 remained robust across all mutant and treatment combinations. Hormone signaling is critical to the response to combined stress and PM, in terms of resistance and plant fitness. ABA appears to be at the crossroads of disease susceptibility/senescence and plant performance under combined stress These gained insights can aid in narrowing down targets for improving crop performance under stress combinations. PMID:28119708

  12. Class III Pistil-Specific Extensin-Like Proteins from Tobacco Have Characteristics of Arabinogalactan Proteins

    Science.gov (United States)

    Bosch, Maurice; Knudsen, Jens Sommer; Derksen, Jan; Mariani, Celestina

    2001-01-01

    Class III pistil-specific extensin-like proteins (PELPIII) are specifically localized in the intercellular matrix of tobacco (Nicotiana tabacum) styles. After pollination the majority of PELPIII are translocated into the callosic layer and the callose plugs of the pollen tubes, which could suggest a function of PELPIII in pollen tube growth. PELPIII may represent one of the chemical and/or physical factors from the female sporophytic tissue that contributes to the difference between in vivo and in vitro pollen tube growth. PELPIII glycoproteins were purified and biochemically characterized. Because of their high proline (Pro) and hydroxy-Pro (Hyp) content, PELPIII proteins belong to the class of Pro/Hyp-rich glycoproteins. The carbohydrate moiety of PELPIII is attached through O-glycosidic linkages and comprises more than one-half the total glycoprotein. Deglycosylation of PELPIII revealed two backbones, both reacting with PELPIII-specific antibodies. N-terminal amino acid sequencing of these backbones showed that PELPIII is encoded by the MG14 and MG15 genes. Two heterogeneous N-terminal sequences of MG14 and MG15, both starting downstream of the predicted signal peptide cleavage site, seem to be present, which indicates a novel N-terminal processing. Monosaccharide analysis showed that the carbohydrate moiety of PELPIII almost completely consists of arabinose and galactose in an equal molar ratio. Carbohydrate linkage analysis showed terminal and 2-linked arabinofuranosyl residues, as well as terminal and 6-, 3-, and 3,6-linked galactopyranosyl residues to be present, indicating the presence of both extensin-like and Type II arabinogalactan oligosaccharide units. The ability of β-glucosyl Yariv reagent to bind with PELPIII confirmed the arabinogalactan protein-like characteristics of these proteins. PMID:11299397

  13. Enhanced Arabidopsis pattern-triggered immunity by overexpression of cysteine-rich receptor-like kinases

    Directory of Open Access Journals (Sweden)

    Yu-Hung eYeh

    2015-05-01

    Full Text Available Upon recognition of microbe-associated molecular patterns (MAMPs such as the bacterial flagellin (or the derived peptide flg22 by pattern-recognition receptors (PRRs such as the FLAGELLIN SENSING2 (FLS2, plants activate the pattern-triggered immunity (PTI response. The L-type lectin receptor kinase-VI.2 (LecRK-VI.2 is a positive regulator of Arabidopsis thaliana PTI. Cysteine-rich receptor-like kinases (CRKs possess two copies of the C-X8-C-X2-C (DUF26 motif in their extracellular domains and are thought to be involved in plant stress resistance, but data about CRK functions are scarce. Here we show that Arabidopsis overexpressing the LecRK-VI.2-responsive CRK4, CRK6 and CRK36 demonstrated an enhanced PTI response and were resistant to virulent bacteria Pseudomonas syringae pv. tomato DC3000. Notably, the flg22-triggered oxidative burst was primed in CRK4, CRK6, and CRK36 transgenics and up-regulation of the PTI-responsive gene FLG22-INDUCED RECEPTOR-LIKE 1 (FRK1 was potentiated upon flg22 treatment in CRK4 and CRK6 overexpression lines or constitutively increased by CRK36 overexpression. PTI-mediated callose deposition was not affected by overexpression of CRK4 and CRK6, while CRK36 overexpression lines demonstrated constitutive accumulation of callose. In addition, Pst DC3000-mediated stomatal reopening was blocked in CRK4 and CRK36 overexpression lines, while overexpression of CRK6 induced constitutive stomatal closure suggesting a strengthening of stomatal immunity. Finally, bimolecular fluorescence complementation and co-immunoprecipitation analyses in Arabidopsis protoplasts suggested that the plasma membrane localized CRK4, CRK6 and CRK36 associate with the PRR FLS2. Association with FLS2 and the observation that overexpression of CRK4, CRK6, and CRK36 boosts specific PTI outputs and resistance to bacteria suggest a role for these CRKs in Arabidopsis innate immunity.

  14. 异己手综合征7例临床及影像学分析%Imaging and Clinical Features of Alien Hand Syndrome

    Institute of Scientific and Technical Information of China (English)

    朱余友; 李淮玉

    2012-01-01

    目的:探讨异己手综合征(AHS)的病因、临床表现、影像学特点以及预后转归.方法:回顾性分析7例AHS患者的临床及影像学资料.结果:以胼胝体型(6/7例)最为多见,主要表现为非优势手的对抗失用或手间冲突(4/6例),71.4%患者由脑梗死所致,6例患者存在胼胝体病变;5例患者在对因治疗1个月时有不同程度好转.结论:AHS临床表现复杂多样,影像学检查对AHS的病因诊断、指导治疗具有重要意义.%Aim: To study imaging feature, etiological factor, the clinical manifestations, imaging feature and prognosis of alien hand syndrome(AHS). Methods: Clinical and imaging records of 7 patients with alien hand syndrome from January 2004 to November 2010 were analyzed retrospectively. Results: Callosal subtype (6/7 cases) was most common and characterized by diagnosed as dyspraxia or intermanual conflict within the non-dominant hand. Followed by the frontal subtype (2/7 cases) and posterior subtype (2/7 cases) associated with AHS; 71.4% were caused by cerebral infarction, especially associated with 6 cases of callosal AHS(85.7%), by multi-focal cerebral infarction. The group of patients were mainly treated etiologically and the data showed that symptoms of 5 patients (71.4) were improved in different degrees after one month treatment. Conclusion: Alien hand syndrome was a rare syndrome characterized by involuntary, uncontrollable, and purposeless movement of one upper limb. Its clinical manifestations were complex and miscellaneous. Imaging examination will be helpful to locate diagnosis and treatment of alien hand syndrome.

  15. DspA/E contributes to apoplastic accumulation of ROS in nonhost A. thaliana

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    Alban eLaunay

    2016-04-01

    Full Text Available The bacterium Erwinia amylovora is responsible for the fire blight disease of Maleae, which provokes necrotic symptoms on aerial parts. The pathogenicity of this bacterium in hosts relies on its type three-secretion system (T3SS, a molecular syringe that allows the bacterium to inject effectors into the plant cell. E. amylovora-triggered disease in host plants is associated with the T3SS-dependent production of reactive oxygen species (ROS, although ROS are generally associated with resistance in other pathosystems. We showed previously that E. amylovora can multiply transiently in the nonhost plant Arabidopsis thaliana and that a T3SS-dependent production of intracellular ROS occurs during this interaction. In the present work we characterize the localization and source of hydrogen peroxide accumulation following E. amylovora infection. Transmission electron microscope (TEM analysis of infected tissues showed that hydrogen peroxide accumulation occurs in the cytosol, plastids, peroxisomes, and mitochondria as well as in the apoplast. Furthermore, TEM analysis showed that an E. amylovora dspA/E-deficient strain does not induce hydrogen peroxide accumulation in the apoplast. Consistently, a transgenic line expressing DspA/E accumulated ROS in the apoplast. The NADPH oxidase-deficient rbohD mutant showed a very strong reduction in hydrogen peroxide accumulation in response to E. amylovora inoculation. However, we did not find an increase in bacterial titers of E. amylovora in the rbohD mutant and the rbohD mutation did not suppress the toxicity of DspA/E when introgressed into a DspA/E-expressing transgenic line. Co-inoculation of E. amylovora with cycloheximide (CHX, which we found previously to suppress callose deposition and allow strong multiplication of E. amylovora in A. thaliana leaves, led to a strong reduction of apoplastic ROS accumulation but did not affect intracellular ROS. Our data strongly suggest that apoplastic ROS accumulation is

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

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    Yun Zhong

    Full Text Available 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

  17. No Silver Bullet – Canonical Poly(ADP-Ribose) Polymerases (PARPs) Are No Universal Factors of Abiotic and Biotic Stress Resistance of Arabidopsis thaliana

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    Rissel, Dagmar; Heym, Peter P.; Thor, Kathrin; Brandt, Wolfgang; Wessjohann, Ludger A.; Peiter, Edgar

    2017-01-01

    Abiotic and biotic stress can have a detrimental impact on plant growth and productivity. Hence, there is a substantial demand for key factors of stress responses to improve yield stability of crops. Members of the poly(ADP-ribose)polymerase (PARP) protein family, which post-translationally modify (PARylate) nuclear proteins, have been suggested as such universal determinants of plant stress responses. A role under abiotic stress has been inferred from studies in which a genetic or, more commonly, pharmacological inhibition of PARP activity improved the performance of stressed plants. To further elucidate the role of PARP proteins under stress, T-DNA knockout mutants for the three Arabidopsis thaliana PARP genes were subjected to drought, osmotic, salt, and oxidative stress. To exclude a functional redundancy, which was indicated by a transcriptional upregulation of the remaining parp genes, a parp triple mutant was generated. Surprisingly, parp mutant plants did not differ from wild type plants in any of these stress experiments, independent from the number of PARP genes mutated. The parp triple mutant was also analyzed for callose formation in response to the pathogenassociated molecular pattern flg22. Unexpectedly, callose formation was unaltered in the mutant, albeit pharmacological PARP inhibition robustly blocked this immune response, confirming previous reports. Evidently, pharmacological inhibition appears to be more robust than the abolition of all PARP genes, indicating the presence of so-far undescribed proteins with PARP activity. This was supported by the finding that protein PARylation was not absent, but even increased in the parp triple mutant. Candidates for novel PARP-inhibitor targets may be found in the SRO protein family. These proteins harbor a catalytic PARP-like domain and are centrally involved in stress responses. Molecular modeling analyses, employing animal PARPs as templates, indeed indicated a capability of the SRO proteins RCD1 and

  18. The role of cell wall-based defences in the early restriction of non-pathogenic hrp mutant bacteria in Arabidopsis.

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    Mitchell, Kathy; Brown, Ian; Knox, Paul; Mansfield, John

    2015-04-01

    We have investigated the cause of the restricted multiplication of hrp mutant bacteria in leaves of Arabidopsis. Our focus was on early interactions leading to differentiation between virulent wild-type and non-pathogenic hrpA mutant strains of Pseudomonas syringae pv. tomato. An initial drop in recoverable bacteria detected 0-4 h after inoculation with either strain was dependent on a functional FLS2 receptor and H2O2 accumulation in challenged leaves. Wild-type bacteria subsequently multiplied rapidly whereas the hrpA mutant was restricted within 6 h. Despite the early restriction, the hrpA mutant was still viable several days after inoculation. Analysis of intercellular washing fluids (IWFs), showed that high levels of nutrients were readily available to bacteria in the apoplast and that no diffusible inhibitors were produced in response to bacterial challenge. Histochemical and immunocytochemical methods were used to detect changes in polysaccharides (callose, two forms of cellulose, and pectin), arabinogalactan proteins (AGPs), H2O2 and peroxidase. Quantitative analysis showed very similar changes in localisation of AGPs, cellulose epitopes and callose 2 and 4 h after inoculation with either strain. However from 6 to 12 h after inoculation papillae expanded only next to the hrp mutant. In contrast to the similar patterns of secretory activity recorded from mesophyll cells, accumulation of H2O2 and peroxidase was significantly greater around the hrpA mutant within the first 4h after inoculation. A striking differential accumulation of H2O2 was also found in chloroplasts in cells next to the mutant. Ascorbate levels were lower in the IWFs recovered from sites inoculated with the hrp mutant than with wild-type bacteria. The critical response, observed at the right time and place to explain the observed differential behaviour of wild-type and hrpA mutant bacteria was the accumulation of H2O2, probably generated through Type III peroxidase activity and in

  19. The transcription factor Nfix is essential for normal brain development

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    Litwack E David

    2008-05-01

    Full Text Available Abstract Background The Nuclear Factor I (NFI multi-gene family encodes site-specific transcription factors essential for the development of a number of organ systems. We showed previously that Nfia-deficient mice exhibit agenesis of the corpus callosum and other forebrain defects; Nfib-deficient mice have defects in lung maturation and show callosal agenesis and forebrain defects resembling those seen in Nfia-deficient animals, while Nfic-deficient mice have defects in tooth root formation. Recently the Nfix gene has been disrupted and these studies indicated that there were largely uncharacterized defects in brain and skeletal development in Nfix-deficient mice. Results Here we show that disruption of Nfix by Cre-recombinase mediated excision of the 2nd exon results in defects in brain development that differ from those seen in Nfia and Nfib KO mice. In particular, complete callosal agenesis is not seen in Nfix-/- mice but rather there appears to be an overabundance of aberrant Pax6- and doublecortin-positive cells in the lateral ventricles of Nfix-/- mice, increased brain weight, expansion of the cingulate cortex and entire brain along the dorsal ventral axis, and aberrant formation of the hippocampus. On standard lab chow Nfix-/- animals show a decreased growth rate from ~P8 to P14, lose weight from ~P14 to P22 and die at ~P22. If their food is supplemented with a soft dough chow from P10, Nfix-/- animals show a lag in weight gain from P8 to P20 but then increase their growth rate. A fraction of the animals survive to adulthood and are fertile. The weight loss correlates with delayed eye and ear canal opening and suggests a delay in the development of several epithelial structures in Nfix-/- animals. Conclusion These data show that Nfix is essential for normal brain development and may be required for neural stem cell homeostasis. The delays seen in eye and ear opening and the brain morphology defects appear independent of the nutritional

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

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    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.

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

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    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

  2. Pantomime to visual presentation of objects: left hand dyspraxia in patients with complete callosotomy.

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    Lausberg, Hedda; Cruz, Robyn F; Kita, Sotaro; Zaidel, Eran; Ptito, Alain

    2003-02-01

    Investigations of left hand praxis in imitation and object use in patients with callosal disconnection have yielded divergent results, inducing a debate between two theoretical positions. Whereas Liepmann suggested that the left hemisphere is motor dominant, others maintain that both hemispheres have equal motor competences and propose that left hand apraxia in patients with callosal disconnection is secondary to left hemispheric specialization for language or other task modalities. The present study aims to gain further insight into the motor competence of the right hemisphere by investigating pantomime of object use in split-brain patients. Three patients with complete callosotomy and, as control groups, five patients with partial callosotomy and nine healthy subjects were examined for their ability to pantomime object use to visual object presentation and demonstrate object manipulation. In each condition, 11 objects were presented to the subjects who pantomimed or demonstrated the object use with either hand. In addition, six object pairs were presented to test bimanual coordination. Two independent raters evaluated the videotaped movement demonstrations. While object use demonstrations were perfect in all three groups, the split-brain patients displayed apraxic errors only with their left hands in the pantomime condition. The movement analysis of concept and execution errors included the examination of ipsilateral versus contralateral motor control. As the right hand/left hemisphere performances demonstrated retrieval of the correct movement concepts, concept errors by the left hand were taken as evidence for right hemisphere control. Several types of execution errors reflected a lack of distal motor control indicating the use of ipsilateral pathways. While one split-brain patient controlled his left hand predominantly by ipsilateral pathways in the pantomime condition, the error profile in the other two split-brain patients suggested that the right hemisphere

  3. Interference of the Histone Deacetylase Inhibits Pollen Germination and Pollen Tube Growth in Picea wilsonii Mast.

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    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.

  4. A T1 and DTI fused 3D corpus callosum analysis in pre- vs. post-season contact sports players

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    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.

  5. Plasmolysis and cell wall deposition in wheat root hairs under osmotic stress.

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    Volgger, Michael; Lang, Ingeborg; Ovecka, Miroslav; Lichtscheidl, Irene

    2010-07-01

    We analysed cell wall formation in rapidly growing root hairs of Triticum aestivum under reduced turgor pressure by application of iso- and hypertonic mannitol solutions. Our experimental series revealed an osmotic value of wheat root hairs of 150 mOsm. In higher concentrations (200-650 mOsm), exocytosis of wall material and its deposition, as well as callose synthesis, still occurred, but the elongation of root hairs was stopped. Even after strong plasmolysis when the protoplast retreated from the cell wall, deposits of wall components were observed. Labelling with DiOC(6)(3) and FM1-43 revealed numerous Hechtian strands that spanned the plasmolytic space. Interestingly, the Hechtian strands also led towards the very tip of the root hair suggesting strong anchoring sites that are readily incorporated into the new cell wall. Long-term treatments of over 24 h in mannitol solutions (150-450 mOsm) resulted in reduced growth and concentration-dependent shortening of root hairs. However, the formation of new root hairs does occur in all concentrations used. This reflects the extraordinary potential of wheat root cells to adapt to environmental stress situations.

  6. Normoergic NO-dependent changes, triggered by a SAR inducer in potato, create more potent defense responses to Phytophthora infestans.

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    Janus, Łukasz; Milczarek, Grzegorz; Arasimowicz-Jelonek, Magdalena; Abramowski, Dariusz; Billert, Hanna; Floryszak-Wieczorek, Jolanta

    2013-10-01

    In our experimental approach we examined how potato leaves exposed to a chemical agent might induce nitric oxide (NO) dependent biochemical modifications for future mobilization of an effective resistance to Phytophthora infestans. After potato leaf treatment with one of the following SAR inducers, i.e. β-aminobutyric acid (BABA), 2,6-dichloroisonicotinic acid (INA) or Laminarin, we observed enhanced NO generation concomitant with biochemical changes related to a slight superoxide anion (O2(-)) and hydrogen peroxide (H2O2) accumulation dependent on minimal NADPH oxidase and peroxidase activities, respectively. These rather normoergic changes, linked to the NO message, were mediated by the temporary down-regulation of S-nitrosoglutathione reductase (GSNOR). In turn, after challenge inoculation signal amplification promoted potato resistance manifested in the up-regulation of GSNOR activity tuned with the depletion of the SNO pool, which was observed by our team earlier (Floryszak-Wieczorek et al., 2012). Moreover, hyperergic defense responses related to an early and rapid O2(-)and H2O2 overproduction together with a temporary increase in NADPH oxidase and peroxidase activities were noted. BABA treatment was the most effective against P. infestans resulting in the enhanced activity of β-1,3-glucanase and callose deposition. Our results indicate that NO-mediated biochemical modifications might play an important role in creating more potent defense responses of potato to a subsequent P. infestans attack.

  7. Mutations in the EDR1 Gene Alter the Response of Arabidopsis thaliana to Phytophthora infestans and the Bacterial PAMPs flg22 and elf18.

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    Geissler, Katrin; Eschen-Lippold, Lennart; Naumann, Kai; Schneeberger, Korbinian; Weigel, Detlef; Scheel, Dierk; Rosahl, Sabine; Westphal, Lore

    2015-02-01

    Mechanistically, nonhost resistance of Arabidopsis thaliana against the oomycete Phytophthora infestans is not well understood. Besides PEN2 and PEN3, which contribute to penetration resistance, no further components have been identified so far. In an ethylmethane sulphonate-mutant screen, we mutagenized pen2-1 and screened for mutants with an altered response to infection by P. infestans. One of the mutants obtained, enhanced response to Phytophthora infestans6 (erp6), was analyzed. Whole-genome sequencing of erp6 revealed a single nucleotide polymorphism in the coding region of the kinase domain of At1g08720, which encodes the putative MAPKKK ENHANCED DISEASE RESISTANCE1 (EDR1). We demonstrate that three independent lines with knock-out alleles of edr1 mount an enhanced response to P. infestans inoculation, mediated by increased salicylic acid signaling and callose deposition. Moreover, we show that the single amino acid substitution in erp6 causes the loss of in vitro autophosphorylation activity of EDR1. Furthermore, growth inhibition experiments suggest a so-far-unknown involvement of EDR1 in the response to the pathogen-associated molecular patterns flg22 and elf18. We conclude that EDR1 contributes to the defense response of A. thaliana against P. infestans. Our data position EDR1 as a negative regulator in postinvasive nonhost resistance.

  8. A Rice Ca2+ Binding Protein Is Required for Tapetum Function and Pollen Formation.

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    Yu, Jing; Meng, Zhaolu; Liang, Wanqi; Behera, Smrutisanjita; Kudla, Jörg; Tucker, Matthew R; Luo, Zhijing; Chen, Mingjiao; Xu, Dawei; Zhao, Guochao; Wang, Jie; Zhang, Siyi; Kim, Yu-Jin; Zhang, Dabing

    2016-11-01

    In flowering plants, successful male reproduction requires the sophisticated interaction between somatic anther wall layers and reproductive cells. Timely degradation of the innermost tissue of the anther wall layer, the tapetal layer, is critical for pollen development. Ca(2+) is a well-known stimulus for plant development, but whether it plays a role in affecting male reproduction remains elusive. Here we report a role of Defective in Exine Formation 1 (OsDEX1) in rice (Oryza sativa), a Ca(2+) binding protein, in regulating rice tapetal cell degradation and pollen formation. In osdex1 anthers, tapetal cell degeneration is delayed and degradation of the callose wall surrounding the microspores is compromised, leading to aborted pollen formation and complete male sterility. OsDEX1 is expressed in tapetal cells and microspores during early anther development. Recombinant OsDEX1 is able to bind Ca(2+) and regulate Ca(2+) homeostasis in vitro, and osdex1 exhibited disturbed Ca(2+) homeostasis in tapetal cells. Phylogenetic analysis suggested that OsDEX1 may have a conserved function in binding Ca(2+) in flowering plants, and genetic complementation of pollen wall defects of an Arabidopsis (Arabidopsis thaliana) dex1 mutant confirmed its evolutionary conservation in pollen development. Collectively, these findings suggest that OsDEX1 plays a fundamental role in the development of tapetal cells and pollen formation, possibly via modulating the Ca(2+) homeostasis during pollen development.

  9. Neural consequences of somatosensory extinction: an fMRI study.

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    Kobayashi, Michiko; Takeda, Katsuhiko; Kaminaga, Tatsuro; Shimizu, Teruo; Iwata, Makoto

    2005-11-01

    There are currently two main interpretations proposing mechanisms underlying tactile extinction: sensory and attention deficit hypotheses. Kinsbourne proposed an opponent processor model to support the attention deficit hypothesis. He insisted that bilateral hemispheres interact reciprocally through contralaterally oriented vectors, and in patients presenting extinction, balance is impaired, causing inattention. From Kinsbourne's point of view, extinction is not caused by sensory disturbance but inattention, therefore even in extinction patients, simultaneous bilateral stimuli should reach the bilateral primary sensory cortices (SI). Using functional magnetic resonance imaging (fMRI), tactile stimuli were administered to both hands of healthy subjects as well as a tactile extinction patient. The patient with tactile extinction extinguished right palm stimuli following simultaneous palm stimulation. During the fMRI study, we gave tactile stimuli to the right palm, the left palm, and simultaneously to both palms. In normal subjects, simultaneous bilateral stimuli activated the bilateral SI and bilateral secondary sensory cortices (SII). In the patient with right tactile extinction, simultaneous bilateral stimuli activated the bilateral SI along with the bilateral SII and right superior parietal lobule. Our study suggests that activation of SI is insufficient to engender an awareness of sensory stimuli. From the view point of Kinsbourne, stimulus driven activity in one hemisphere suppresses activity in the other hemisphere via callosal connections. Our results support the notion that an undamaged superior parietal lobule in the patient with tactile extinction suppresses the damaged parietal lobe function and causes extinction.

  10. Induced Systemic Resistance against Botrytis cinerea by Bacillus cereus AR156 through a JA/ET- and NPR1-Dependent Signaling Pathway and Activates PAMP-Triggered Immunity in Arabidopsis

    Science.gov (United States)

    Nie, Pingping; Li, Xia; Wang, Shune; Guo, Jianhua; Zhao, Hongwei; Niu, Dongdong

    2017-01-01

    Induced resistance response is a potent and cost effective plant defense against pathogen attack. The effectiveness and underlying mechanisms of the suppressive ability by Bacillus cereus AR156 to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) in Arabidopsis has been investigated previously; however, the strength of induced systemic resistance (ISR) activity against Botrytis cinerea remains unknown. Here, we show that root-drench application of AR156 significantly reduces disease incidence through activation of ISR. This protection is accompanied with multilayered ISR defense response activated via enhanced accumulation of PR1 protein expression in a timely manner, hydrogen peroxide accumulation and callose deposition, which is significantly more intense in plants with both AR156 pretreatment and B. cinerea inoculation than that in plants with pathogen inoculation only. Moreover, AR156 can trigger ISR in sid2-2 and NahG mutants, but not in jar1, ein2 and npr1 mutant plants. Our results indicate that AR156-induced ISR depends on JA/ET-signaling pathway and NPR1, but not SA. Also, AR156-treated plants are able to rapidly activate MAPK signaling and FRK1/WRKY53 gene expression, both of which are involved in pathogen associated molecular pattern (PAMP)-triggered immunity (PTI). The results indicate that AR156 can induce ISR by the JA/ET-signaling pathways in an NPR1-dependent manner and involves multiple PTI components. PMID:28293243

  11. Simultaneously Cooperative, but Serially Antagonistic: A Neuropsychological Study of Diagonistic Dyspraxia in a Case of Marchiafava-Bignami Disease

    Directory of Open Access Journals (Sweden)

    Kazumi Hirayama

    2008-01-01

    Full Text Available We describe a patient with Marchiafava-Bignami disease who showed, in addition to signs of callosal interruption, a peculiar form of diagonistic dyspraxia. Unlike the typical diagonistic dyspraxia, both of the patient’s hands could simultaneously cooperate in a sequence of bimanual actions. More specifically, his right hand could start a commanded action with the cooperation of his left hand. However, once the action was completed, his left hand started an antagonistic action, undoing the result, with the cooperation of his right hand. Once this countermanding action was completed, the original action started again. These antagonistic actions repeated themselves alternately unless he was restrained. The patient's diagonistic dyspraxia was apparent in only some bimanual actions, and he showed no diagonistic dyspraxia when performing voluntary actions; the antagonistic actions occurred in response to oral commands or by imitation. Magnetic resonance imaging showed symmetrical demyelination with partial necrosis in the genu, body, and anterior splenium of the corpus callosum. We speculate that the bimanual coordination is possible because part of the corpus callosum is intact, whereas the antagonistic actions may be caused by conflict between the two hemispheres due to interhemispheric disinhibition elicited by the demyelinated part of the corpus callosum.

  12. Differential Effects of Brain Disorders on Structural and Functional Connectivity

    Science.gov (United States)

    Vega-Pons, Sandro; Olivetti, Emanuele; Avesani, Paolo; Dodero, Luca; Gozzi, Alessandro; Bifone, Angelo

    2017-01-01

    Different measures of brain connectivity can be defined based on neuroimaging read-outs, including structural and functional connectivity. Neurological and psychiatric conditions are often associated with abnormal connectivity, but comparing the effects of the disease on different types of connectivity remains a challenge. In this paper, we address the problem of quantifying the relative effects of brain disease on structural and functional connectivity at a group level. Within the framework of a graph representation of connectivity, we introduce a kernel two-sample test as an effective method to assess the difference between the patients and control group. Moreover, we propose a common representation space for structural and functional connectivity networks, and a novel test statistics to quantitatively assess differential effects of the disease on different types of connectivity. We apply this approach to a dataset from BTBR mice, a murine model of Agenesis of the Corpus Callosum (ACC), a congenital disorder characterized by the absence of the main bundle of fibers connecting the two hemispheres. We used normo-callosal mice (B6) as a comparator. The application of the proposed methods to this data-set shows that the two types of connectivity can be successfully used to discriminate between BTBR and B6, meaning that both types of connectivity are affected by ACC. However, our novel test statistics shows that structural connectivity is significantly more affected than functional connectivity, consistent with the idea that functional connectivity has a robust topology that can tolerate substantial alterations in its structural connectivity substrate. PMID:28119556

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

    Directory of Open Access Journals (Sweden)

    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.

  14. De Novo Transcriptome Sequencing of Olea europaea L. to Identify Genes Involved in the Development of the Pollen Tube

    Directory of Open Access Journals (Sweden)

    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.

  15. De Novo Transcriptome Sequencing of Olea europaea L. to Identify Genes Involved in the Development of the Pollen Tube.

    Science.gov (United States)

    Iaria, Domenico; Chiappetta, Adriana; Muzzalupo, Innocenzo

    2016-01-01

    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 Ca(2+) 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. BURSTING POLLEN is required to organize the pollen germination plaque and pollen tube tip in Arabidopsis thaliana.

    Science.gov (United States)

    Hoedemaekers, Karin; Derksen, Jan; Hoogstrate, Suzanne W; Wolters-Arts, Mieke; Oh, Sung-Aeong; Twell, David; Mariani, Celestina; Rieu, Ivo

    2015-04-01

    Pollen germination may occur via the so-called germination pores or directly through the pollen wall at the site of contact with the stigma. In this study, we addressed what processes take place during pollen hydration (i.e. before tube emergence), in a species with extra-poral pollen germination, Arabidopsis thaliana. A T-DNA mutant population was screened by segregation distortion analysis. Histological and electron microscopy techniques were applied to examine the wild-type and mutant phenotypes. Within 1 h of the start of pollen hydration, an intine-like structure consisting of cellulose, callose and at least partly de-esterified pectin was formed at the pollen wall. Subsequently, this 'germination plaque' gradually extended and opened up to provide passage for the cytoplasm into the emerging pollen tube. BURSTING POLLEN (BUP) was identified as a gene essential for the correct organization of this plaque and the tip of the pollen tube. BUP encodes a novel Golgi-located glycosyltransferase related to the glycosyltransferase 4 (GT4) subfamily which is conserved throughout the plant kingdom. Extra-poral pollen germination involves the development of a germination plaque and BUP defines the correct plastic-elastic properties of this plaque and the pollen tube tip by affecting pectin synthesis or delivery.

  17. Membrane-Associated Ubiquitin Ligase SAUL1 Suppresses Temperature- and Humidity-Dependent Autoimmunity in Arabidopsis.

    Science.gov (United States)

    Disch, Eva-Maria; Tong, Meixuezi; Kotur, Tanja; Koch, Gerald; Wolf, Carl-Asmus; Li, Xin; Hoth, Stefan

    2016-01-01

    Plants have evolved elaborate mechanisms to regulate pathogen defense. Imbalances in this regulation may result in autoimmune responses that are affecting plant growth and development. In Arabidopsis, SAUL1 encodes a plant U-box ubiquitin ligase and regulates senescence and cell death. Here, we show that saul1-1 plants exhibit characteristics of an autoimmune mutant. A decrease in relative humidity or temperature resulted in reduced growth and systemic lesioning of saul1-1 rosettes. These physiological changes are associated with increased expression of salicylic acid-dependent and pathogenesis-related (PR) genes. Consistently, resistance of saul1-1 plants against Pseudomonas syringae pv. maculicola ES4326, P. syringae pv. tomato DC3000, or Hyaloperonospora arabidopsidis Noco2 was enhanced. Transmission electron microscopy revealed alterations in saul1-1 chloroplast ultrastructure and cell-wall depositions. Confocal analysis on aniline blue-stained leaf sections and cellular universal micro spectrophotometry further showed that these cell-wall depositions contain callose and lignin. To analyze signaling downstream of SAUL1, we performed epistasis analyses between saul1-1 and mutants in the EDS1/PAD4/SAG101 hub. All phenotypes observed in saul1-1 plants at low temperature were dependent on EDS1 and PAD4 but not SAG101. Taken together, SAUL1 negatively regulates immunity upstream of EDS1/PAD4, likely through the degradation of an unknown activator of the pathway.

  18. Simultaneously cooperative, but serially antagonistic: a neuropsychological study of diagonistic dyspraxia in a case of Marchiafava-Bignami disease.

    Science.gov (United States)

    Hirayama, Kazumi; Tachibana, Kaori; Abe, Nobuhito; Manabe, Hideaki; Fuse, Takahisa; Tsukamoto, Tetsuro

    2008-01-01

    We describe a patient with Marchiafava-Bignami disease who showed, in addition to signs of callosal interruption, a peculiar form of diagonistic dyspraxia. Unlike the typical diagonistic dyspraxia, both of the patient's hands could simultaneously cooperate in a sequence of bimanual actions. More specifically, his right hand could start a commanded action with the cooperation of his left hand. However, once the action was completed, his left hand started an antagonistic action, undoing the result, with the cooperation of his right hand. Once this countermanding action was completed, the original action started again. These antagonistic actions repeated themselves alternately unless he was restrained. The patient's diagonistic dyspraxia was apparent in only some bimanual actions, and he showed no diagonistic dyspraxia when performing voluntary actions; the antagonistic actions occurred in response to oral commands or by imitation. Magnetic resonance imaging showed symmetrical demyelination with partial necrosis in the genu, body, and anterior splenium of the corpus callosum. We speculate that the bimanual coordination is possible because part of the corpus callosum is intact, whereas the antagonistic actions may be caused by conflict between the two hemispheres due to interhemispheric disinhibition elicited by the demyelinated part of the corpus callosum.

  19. Microbial modulation of bacoside A biosynthetic pathway and systemic defense mechanism in Bacopa monnieri under Meloidogyne incognita stress

    Science.gov (United States)

    Gupta, Rupali; Singh, Akanksha; Srivastava, Madhumita; Singh, Vivek; Gupta, M. M.; Pandey, Rakesh

    2017-01-01

    Plant-associated beneficial microbes have been explored to fulfill the imperative function for plant health. However, their impact on the host secondary metabolite production and nematode disease management remains elusive. Our present work has shown that chitinolytic microbes viz., Chitiniphilus sp. MTN22 and Streptomyces sp. MTN14 singly as well as in combination modulated the biosynthetic pathway of bacoside A and systemic defense mechanism against Meloidogyne incognita in Bacopa monnieri. Interestingly, expression of bacoside biosynthetic pathway genes (3-Hydroxy-3-methylglutaryl coenzyme A reductase, mevalonate diphosphate decarboxylase, and squalene synthase) were upregulated in plants treated with the microbial combination in the presence as well as in absence of M. incognita stress. These microbes not only augmented bacoside A production (1.5 fold) but also strengthened host resistance via enhancement in chlorophyll a, defense enzymes and phenolic compounds like gallic acid, syringic acid, ferulic acid and cinnamic acid. Furthermore, elevated lignification and callose deposition in the microbial combination treated plants corroborate well with the above findings. Overall, the results provide novel insights into the underlying mechanisms of priming by beneficial microbes and underscore their capacity to trigger bacoside A production in B. monnieri under biotic stress. PMID:28157221

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  1. Environmental History Modulates Arabidopsis Pattern-Triggered Immunity in a HISTONE ACETYLTRANSFERASE1-Dependent Manner.

    Science.gov (United States)

    Singh, Prashant; Yekondi, Shweta; Chen, Po-Wen; Tsai, Chia-Hong; Yu, Chun-Wei; Wu, Keqiang; Zimmerli, Laurent

    2014-06-01

    In nature, plants are exposed to a fluctuating environment, and individuals exposed to contrasting environmental factors develop different environmental histories. Whether different environmental histories alter plant responses to a current stress remains elusive. Here, we show that environmental history modulates the plant response to microbial pathogens. Arabidopsis thaliana plants exposed to repetitive heat, cold, or salt stress were more resistant to virulent bacteria than Arabidopsis grown in a more stable environment. By contrast, long-term exposure to heat, cold, or exposure to high concentrations of NaCl did not provide enhanced protection against bacteria. Enhanced resistance occurred with priming of Arabidopsis pattern-triggered immunity (PTI)-responsive genes and the potentiation of PTI-mediated callose deposition. In repetitively stress-challenged Arabidopsis, PTI-responsive genes showed enrichment for epigenetic marks associated with transcriptional activation. Upon bacterial infection, enrichment of RNA polymerase II at primed PTI marker genes was observed in environmentally challenged Arabidopsis. Finally, repetitively stress-challenged histone acetyltransferase1-1 (hac1-1) mutants failed to demonstrate enhanced resistance to bacteria, priming of PTI, and increased open chromatin states. These findings reveal that environmental history shapes the plant response to bacteria through the development of a HAC1-dependent epigenetic mark characteristic of a primed PTI response, demonstrating a mechanistic link between the primed state in plants and epigenetics.

  2. Case Report: 84 year-old woman with alien hand syndrome [version 1; referees: 2 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    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.

  3. Interconnection between actin cytoskeleton and plant defense signaling.

    Science.gov (United States)

    Janda, Martin; Matoušková, Jindřiška; Burketová, Lenka; Valentová, Olga

    2014-01-01

    Actin cytoskeleton is the fundamental structural component of eukaryotic cells. It has a role in numerous elementary cellular processes such as reproduction, development and also in response to abiotic and biotic stimuli. Remarkably, the role of actin cytoskeleton in plant response to pathogens is getting to be under magnifying glass. Based on microscopic studies, most of the data showed, that actin plays an important role in formation of physiological barrier in the site of infection. Actin dynamics is involved in the transport of antimicrobial compounds and cell wall fortifying components (e.g. callose) to the site of infection. Also the role in PTI (pathogen triggered immunity) and ETI (effector triggered immunity) was recently indicated. On the other hand much less is known about the transcriptome reprogramming upon changes in actin dynamics. Our recently published results showed that drugs inhibiting actin polymerization (latrunculin B, cytochalasin E) cause the induction of genes which are involved in salicylic acid (SA) signaling pathway. In this addendum we would like to highlight in more details current state of knowledge concerning the involvement of actin dynamics in plant defense signaling.

  4. Study of the Etiological Causes of Toe Web Space Lesions in Cairo, Egypt

    Directory of Open Access Journals (Sweden)

    Hussein Mohamed Hassab-El-Naby

    2015-01-01

    Full Text Available Background. The etiology of foot intertrigo is varied. Several pathogens and skin conditions might play a role in toe web space lesions. Objective. To identify the possible etiological causes of toe web space lesions. Methods. 100 Egyptian patients were enrolled in this study (72 females and 28 males. Their ages ranged from 18 to 79 years. For every patient, detailed history taking, general and skin examinations, and investigations including Wood’s light examination, skin scraping for potassium hydroxide test, skin swabs for bacterial isolation, and skin biopsy all were done. Results. Among the 100 patients, positive Wood’s light fluorescence was observed in 24 and positive bacterial growth was observed in 85. With skin biopsy, 52 patients showed features characteristic for eczema, 25 showed features characteristic for fungus, 19 showed features characteristic for callosity, and 3 showed features characteristic for wart while in only 1 patient the features were characteristic for lichen planus. Conclusion. Toe web space lesions are caused by different etiological factors. The most common was interdigital eczema (52% followed by fungal infection (25%. We suggest that patients who do not respond to antifungals should be reexamined for another primary or secondary dermatologic condition that may resemble interdigital fungal infection.

  5. Study of the Etiological Causes of Toe Web Space Lesions in Cairo, Egypt.

    Science.gov (United States)

    Hassab-El-Naby, Hussein Mohamed; Mohamed, Yasser Fathy; Abdo, Hamed Mohamed; Kamel, Mohamed Ismail; Hablas, Wael Refaat; Mohamed, Osama Khalil

    2015-01-01

    Background. The etiology of foot intertrigo is varied. Several pathogens and skin conditions might play a role in toe web space lesions. Objective. To identify the possible etiological causes of toe web space lesions. Methods. 100 Egyptian patients were enrolled in this study (72 females and 28 males). Their ages ranged from 18 to 79 years. For every patient, detailed history taking, general and skin examinations, and investigations including Wood's light examination, skin scraping for potassium hydroxide test, skin swabs for bacterial isolation, and skin biopsy all were done. Results. Among the 100 patients, positive Wood's light fluorescence was observed in 24 and positive bacterial growth was observed in 85. With skin biopsy, 52 patients showed features characteristic for eczema, 25 showed features characteristic for fungus, 19 showed features characteristic for callosity, and 3 showed features characteristic for wart while in only 1 patient the features were characteristic for lichen planus. Conclusion. Toe web space lesions are caused by different etiological factors. The most common was interdigital eczema (52%) followed by fungal infection (25%). We suggest that patients who do not respond to antifungals should be reexamined for another primary or secondary dermatologic condition that may resemble interdigital fungal infection.

  6. Hemispheric specialization and independence for word recognition: a comparison of three computational models.

    Science.gov (United States)

    Weems, Scott A; Reggia, James A

    2004-06-01

    Two findings serve as the hallmark for hemispheric specialization during lateralized lexical decision. First is an overall word advantage, with words being recognized more quickly and accurately than non-words (the effect being stronger in response latency). Second, a right visual field advantage is observed for words, with little or no hemispheric differences in the ability to identify non-words. Several theories have been proposed to account for this difference in word and non-word recognition, some by suggesting dual routes of lexical access and others by incorporating separate, and potentially independent, word and non-word detection mechanisms. We compare three previously proposed cognitive theories of hemispheric interactions (callosal relay, direct access, and cooperative hemispheres) through neural network modeling, with each network incorporating different means of interhemispheric communication. When parameters were varied to simulate left hemisphere specialization for lexical decision, only the cooperative hemispheres model showed both a consistent left hemisphere advantage for word recognition but not non-word recognition, as well as an overall word advantage. These results support the theory that neural representations of words are more strongly established in the left hemisphere through prior learning, despite open communication between the hemispheres during both learning and recall.

  7. Tobacco mosaic virus infection results in an increase in recombination frequency and resistance to viral, bacterial, and fungal pathogens in the progeny of infected tobacco plants.

    Science.gov (United States)

    Kathiria, Palak; Sidler, Corinne; Golubov, Andrey; Kalischuk, Melanie; Kawchuk, Lawrence M; Kovalchuk, Igor

    2010-08-01

    Our previous experiments showed that infection of tobacco (Nicotiana tabacum) plants with Tobacco mosaic virus (TMV) leads to an increase in homologous recombination frequency (HRF). The progeny of infected plants also had an increased rate of rearrangements in resistance gene-like loci. Here, we report that tobacco plants infected with TMV exhibited an increase in HRF in two consecutive generations. Analysis of global genome methylation showed the hypermethylated genome in both generations of plants, whereas analysis of methylation via 5-methyl cytosine antibodies demonstrated both hypomethylation and hypermethylation. Analysis of the response of the progeny of infected plants to TMV, Pseudomonas syringae, or Phytophthora nicotianae revealed a significant delay in symptom development. Infection of these plants with TMV or P. syringae showed higher levels of induction of PATHOGENESIS-RELATED GENE1 gene expression and higher levels of callose deposition. Our experiments suggest that viral infection triggers specific changes in progeny that promote higher levels of HRF at the transgene and higher resistance to stress as compared with the progeny of unstressed plants. However, data reported in these studies do not establish evidence of a link between recombination frequency and stress resistance.

  8. A Review of Inhibiting Disease of Fruits and Vegetables by Chitosan and Its Action Mechanism%壳聚糖对果蔬病害的抑制及其作用机理

    Institute of Scientific and Technical Information of China (English)

    蒋璇靓; 郑江枫; 林河通; 林艺芬; 陈艺晖; 林钟铨; 陈梦茵

    2013-01-01

    壳聚糖是一种天然的阳离子聚合物,对许多细菌、真菌有很好的抑制作用,在控制果蔬等植物病害方面极具应用前景.壳聚糖作为果蔬等植物抗性反应的激发子,它能迅速激发果蔬等植物的防卫反应,包括诱导植保素、病程相关蛋白、蛋白酶抑制剂、木质素和胼胝质等的合成,启动果蔬等植物的防御系统,有效地提高果蔬的抗病性.%Chitosan, an important natural biopolymer, shows a good inhibition for bacteria and fungi and has potential using in controlling diseases of fruit and vegetable. Chitosan,as an elicitor of resistant reaction for fruit and vegetable, can rapidly stimulate defense responses of plant such as fruit and vegetable, which induce the synthesis of phytoalexin,pathogenesis-related(PR) proteins,protease inhibitors,lignin and callose. Moreover , chitosan, startups defensive system of plants such as fruit and vegetable, and effectively improve disease resistance of fruit and vegetable.

  9. Cytokinesis in plant male meiosis.

    Science.gov (United States)

    De Storme, Nico; Geelen, Danny

    2013-03-01

    In somatic cell division, cytokinesis is the final step of the cell cycle and physically divides the mother cytoplasm into two daughter cells. In the meiotic cell division, however, pollen mother cells (PMCs) undergo two successive nuclear divisions without an intervening S-phase and consequently generate four haploid daughter nuclei out of one parental cell. In line with this, the physical separation of meiotic nuclei does not follow the conventional cytokinesis pathway, but instead is mediated by alternative processes, including polar-based phragmoplast outgrowth and RMA-mediated cell wall positioning. In this review, we outline the different cytological mechanisms of cell plate formation operating in different types of PMCs and additionally focus on some important features associated with male meiotic cytokinesis, including cytoskeletal dynamics and callose deposition. We also provide an up-to-date overview of the main molecular actors involved in PMC wall formation and additionally highlight some recent advances on the effect of cold stress on meiotic cytokinesis in plants.

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

    Science.gov (United States)

    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.

  11. Progressive apraxic agraphia with micrographia presenting as corticobasal syndrome showing extensive Pittsburgh compound B uptake.

    Science.gov (United States)

    Sakurai, Yasuhisa; Ishii, Kenji; Sonoo, Masahiro; Saito, Yuko; Murayama, Shigeo; Iwata, Atsushi; Hamada, Kensuke; Sugimoto, Izumi; Tsuji, Shoji; Mannen, Toru

    2013-08-01

    A 65-year-old woman developed progressive apraxic agraphia, characterized by poorly formed graphemes, a kanji (Japanese morphograms) recall impairment, relatively preserved oral spelling of kanji characters, and incorrect stroke sequences on writing accompanied by micrographia over a 3-year period. She also showed minor degrees of rigidity, limb-kinetic apraxia, and ideomotor apraxia of the left hand. Although asymmetric rigidity and limb-kinetic apraxia strongly suggested corticobasal degeneration, (11)C-Pittsburgh compound B positron emission tomography (PiB-PET) showed the predominantly right-sided accumulation of amyloid β in the cortices and striatum. (18)F-fluoro-deoxy-glucose PET and single photon emission computed tomography with a (99m)Tc-ethylcysteinate dimer (ECD-SPECT) also revealed predominantly right-sided hypometabolism and hypoperfusion in the primary sensorimotor cortex, posterior cingulate gyrus, temporoparietal cortices, frontal cortices, thalamus, and basal ganglia, a pattern characteristic of both corticobasal degeneration and Alzheimer's disease. The findings suggest that progressive apraxic agraphia with micrographia presenting as corticobasal syndrome can show an Alzheimer's disease pathology. It is also suggested that ideomotor apraxia of the left hand can occur without a callosal lesion, and is caused by hypometabolism or hypoperfusion in the right frontal and parietal cortices, as revealed by PET and SPECT.

  12. Elicitation of resistance and associated defense responses in Trichoderma hamatum induced protection against pearl millet downy mildew pathogen

    Science.gov (United States)

    Siddaiah, Chandra Nayaka; Satyanarayana, Niranjan Raj; Mudili, Venkataramana; Kumar Gupta, Vijai; Gurunathan, Selvakumar; Rangappa, Shobith; Huntrike, Shekar Shetty; Srivastava, Rakesh Kumar

    2017-01-01

    Endophytic Trichoderma hamatum UoM 13 isolated from pearl millet roots was evaluated for its efficiency to suppress downy mildew disease. Under laboratory conditions, T. hamatum seed treatment significantly enhanced pearl millet seed germination and seedling vigor. T. hamatum seed treatment resulted in systemic and durable immunity against pearl millet downy mildew disease under greenhouse and field conditions. T. hamatum treated seedlings responded to downy mildew infection with high lignification and callose deposition. Analysis of defense enzymes showed that T. hamatum treatment significantly enhanced the activities of glucanase, peroxidase, phenylalanine ammonia-lyase, and polyphenol oxidase in comparison to untreated control. RT-PCR analysis revealed differentially expressed transcripts of the defense enzymes and PR-proteins in treated, untreated, and checks, wherein PR-1, PR-5, and cell wall defense HRGPs were significantly over expressed in treated seedlings as against their lower expression in controls. T. hamatum treatment significantly stimulated endogenous salicylic acid (SA) levels and significantly upregulated important SA biosynthesis gene isochorismate synthase. The results indicated that T. hamatum UoM13 treatment induces resistance corresponding to significant over expression of endogenous SA, important defense enzymes, PR-proteins, and HRGPs, suggesting that SA biosynthetic pathway is involved in pearl millet for mounting systemic immunity against downy mildew pathogen. PMID:28322224

  13. Timing in neural maturation: arrest, delay, precociousness, and temporal determination of malformations.

    Science.gov (United States)

    Sarnat, Harvey B; Philippart, Michel; Flores-Sarnat, Laura; Wei, Xing-Chang

    2015-05-01

    Timing is primordial in initiating and synchronizing each developmental process in tissue morphogenesis. Maturational arrest, delay, and precociousness all are conducive to neurological dysfunction and may determine different malformations depending on when in development the faulty timing occurred, regardless of the identification of a specific genetic mutation or an epigenetic teratogenic event. Delay and arrest are distinguished by whether further progressive development over time can be expected or the condition is static. In general, retardation of early developmental processes, such as neurulation, cellular proliferation, and migration, leads to maturational arrest. Retardation of late processes, such as synaptogenesis and myelination, are more likely to result in maturational delay. Faulty timing of neuronal maturation in relation to other developmental processes causes neurological dysfunction and abnormal electroencephalograph maturation in preterm neonates. Precocious synaptogenesis, including pruning to provide plasticity, may facilitate prenatal formation of epileptic circuitry leading to severe postnatal infantile epilepsies. The anterior commissure forms 3 weeks earlier than the corpus callosum; its presence or absence in callosal agenesis is a marker for the onset of the initial insult. An excessively thick corpus callosum may be due to delayed retraction of transitory collateral axons. Malformations that arise at different times can share a common pathogenesis with variations on the extent: timing of mitotic cycles in mosaic somatic mutations may distinguish hemimegalencephaly from focal cortical dysplasia type 2. Timing should always be considered in interpreting cerebral dysgeneses in both imaging and neuropathological diagnoses.

  14. Instructing Perisomatic Inhibition by Direct Lineage Reprogramming of Neocortical Projection Neurons.

    Science.gov (United States)

    Ye, Zhanlei; Mostajo-Radji, Mohammed A; Brown, Juliana R; Rouaux, Caroline; Tomassy, Giulio Srubek; Hensch, Takao K; Arlotta, Paola

    2015-11-01

    During development of the cerebral cortex, local GABAergic interneurons recognize and pair with excitatory projection neurons to ensure the fine excitatory-inhibitory balance essential for proper circuit function. Whether the class-specific identity of projection neurons has a role in the establishment of afferent inhibitory synapses is debated. Here, we report that direct in vivo lineage reprogramming of layer 2/3 (L2/3) callosal projection neurons (CPNs) into induced corticofugal projection neurons (iCFuPNs) increases inhibitory input onto the converted neurons to levels similar to that of endogenous CFuPNs normally found in layer 5 (L5). iCFuPNs recruit increased numbers of inhibitory perisomatic synapses from parvalbumin (PV)-positive interneurons, with single-cell precision and despite their ectopic location in L2/3. The data show that individual reprogrammed excitatory projection neurons extrinsically modulate afferent input by local PV(+) interneurons, suggesting that projection neuron class-specific identity can actively control the wiring of the cortical microcircuit.

  15. Schizophrenia, abnormal connection, and brain evolution.

    Science.gov (United States)

    Randall, P L

    1983-03-01

    Abnormalities of functional connection between specialized areas in the human brain may underlie the symptoms which constitute the schizophrenia syndrome. Callosal and intrahemispheric fibres may be equally involved. The clinical emergence of symptoms in the later stages of brain maturation may be dependent on myelination of these fibre groups, both of which have extended myelination cycles. Ontogenetically earlier variants of the same mechanism could theoretically result in dyslexia and the syndromes of Kanner and Gilles de la Tourette. As new and unique extensions of specialized function emerge within the evolving brain, biological trial and error of connection both within and between them may produce individuals possessing phylogenetically advanced abilities, or equally, others possessing a wide range of abnormalities including those which comprise the schizophrenia syndrome. A dormant phenotypic potential for schizophrenia may exist in individuals who never develop symptoms during the course of a lifetime though some of these may become clinically apparent under the influence of various precipitating factors. It is concluded that abnormal functional connection and its normal and "supernormal" counterparts may be natural, essential, and inevitable consequences of brain evolution, and that this may have been so throughout the history of vertebrate brain evolution.

  16. The Novel Oomycide Oxathiapiprolin Inhibits All Stages in the Asexual Life Cycle of Pseudoperonospora cubensis - Causal Agent of Cucurbit Downy Mildew.

    Directory of Open Access Journals (Sweden)

    Yigal Cohen

    Full Text Available Oxathiapiprolin is a new oomycide (piperidinyl thiazole isoxazoline class discovered by DuPont which controls diseases caused by oomycete plant pathogens. It binds in the oxysterol-binding protein domain of Oomycetes. Growth chambers studies with detached leaves and potted plants showed remarkable activity of oxathiapiprolin against Pseudoperonospora cubensis in cucurbits. The compound affected all stages in the asexual life cycle of the pathogen. It inhibited zoospore release, cystospore germination, lesion formation, lesion expansion, sporangiophore development and sporangial production. When applied to the foliage as a preventive spray no lesions developed due to inhibition of zoospore release and cystospore germination, and when applied curatively, at one or two days after inoculation, small restricted lesions developed but no sporulation occurred. When applied later to mature lesions, sporulation was strongly inhibited. Oxathiapiprolin suppressed sporulation of P. cubensis in naturally-infected leaves. It exhibited trans-laminar activity, translocated acropetaly from older to younger leaves, and moved from the root system to the foliage. Seed coating was highly effective in protecting the developed cucumber plants against downy mildew. UV microscopy observations made with cucumber leaves infected with P. cubensis revealed that inhibition of mycelium growth and sporulation induced by oxathiapiprolin was associated with callose encasement of the haustoria.

  17. 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.

  18. Single-shot T1 mapping of the corpus callosum: a rapid characterization of fiber bundle anatomy.

    Science.gov (United States)

    Hofer, Sabine; Wang, Xiaoqing; Roeloffs, Volkert; Frahm, Jens

    2015-01-01

    Using diffusion-tensor magnetic resonance imaging and fiber tractography the topographic organization of the human corpus callosum (CC) has been described to comprise five 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.

  19. Single-shot T1 mapping of the corpus callosum: A rapid characterization of fiber bundle anatomy

    Directory of Open Access Journals (Sweden)

    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.

  20. 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.

  1. 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.

  2. A prospective study of Japas′ osteotomy in paralytic pes cavus deformity in adolescent feet

    Directory of Open Access Journals (Sweden)

    Chatterjee Protyush

    2009-01-01

    Full Text Available Background: Pes cavus is a progressive and ugly deformity of the foot. Although initially the deformity is painless, with time, painful callosities develop under metatarsal heads and arthritis supervenes later in feet. Mild deformities can be treated with corrective shoes, or foot exercises. However, in others, operative treatment is imperative. Soft tissue operations are largely unsatisfactory and temporary. Bony operations give permanent correction. We present our series of 18 patients of pes cavus in the adolescent age group, treated by Japas′ V-osteotomy of the tarsus. Materials and Methods: 18 patients of paralytic pes cavus deformity were treated by Japas osteotomy, between March 1995 and 2005, at our institute. The age of the patients ranged from 8.6 to 15 years (mean 11.3; 10 were boys and 8 girls. All cases had unilateral involvement, and all, but one, were post-polio cases. Result: The mean follow-up is 5.4 years. Of the 18 patients, 14 had excellent or good corrections; 4 had poor correction/complications. However, those patients could be salvaged by triple arthordesis or Dwyer′s calcaneal osteotomy. Conclusion: Japas′ osteotomy is a satisfactory option for correction of pes cavus deformity in adolescents. In patients who have rigid hind foot equinus or varus, however, the results are compromised.

  3. An integrative analysis of four CESA isoforms specific for fiber cellulose production between Gossypium hirsutum and Gossypium barbadense.

    Science.gov (United States)

    Li, Ao; Xia, Tao; Xu, Wen; Chen, Tingting; Li, Xianliang; Fan, Jian; Wang, Ruyi; Feng, Shengqiu; Wang, Yanting; Wang, Bingrui; Peng, Liangcai

    2013-06-01

    Cotton fiber is an excellent model system of cellulose biosynthesis; however, it has not been widely studied due to the lack of information about the cellulose synthase (CESA) family of genes in cotton. In this study, we initially identified six full-length CESA genes designated as GhCESA5-GhCESA10. Phylogenetic analysis and gene co-expression profiling revealed that CESA1, CESA2, CESA7, and CESA8 were the major isoforms for secondary cell wall biosynthesis, whereas CESA3, CESA5, CESA6, CESA9, and CESA10 should involve in primary cell wall formation for cotton fiber initiation and elongation. Using integrative analysis of gene expression patterns, CESA protein levels, and cellulose biosynthesis in vivo, we detected that CESA8 could play an enhancing role for rapid and massive cellulose accumulation in Gossypium hirsutum and Gossypium barbadense. We found that CESA2 displayed a major expression in non-fiber tissues and that CESA1, a housekeeping gene like, was predominantly expressed in all tissues. Further, a dynamic alteration was observed in cell wall composition and a significant discrepancy was observed between the cotton species during fiber elongation, suggesting that pectin accumulation and xyloglucan reduction might contribute to cell wall transition. In addition, we discussed that callose synthesis might be regulated in vivo for massive cellulose production during active secondary cell wall biosynthesis in cotton fibers.

  4. Thaxtomin A affects CESA-complex density, expression of cell wall genes, cell wall composition, and causes ectopic lignification in Arabidopsis thaliana seedlings.

    Science.gov (United States)

    Bischoff, Volker; Cookson, Sarah Jane; Wu, Shuang; Scheible, Wolf-Rüdiger

    2009-01-01

    Thaxtomin A, a phytotoxin produced by Streptomyces eubacteria, is suspected to act as a natural cellulose synthesis inhibitor. This view is confirmed by the results obtained from new chemical, molecular, and microscopic analyses of Arabidopsis thaliana seedlings treated with thaxtomin A. Cell wall analysis shows that thaxtomin A reduces crystalline cellulose, and increases pectins and hemicellulose in the cell wall. Treatment with thaxtomin A also changes the expression of genes involved in primary and secondary cellulose synthesis as well as genes associated with pectin metabolism and cell wall remodelling, in a manner nearly identical to isoxaben. In addition, it induces the expression of several defence-related genes and leads to callose deposition. Defects in cellulose synthesis cause ectopic lignification phenotypes in A. thaliana, and it is shown that lignification is also triggered by thaxtomin A, although in a pattern different from isoxaben. Spinning disc confocal microscopy further reveals that thaxtomin A depletes cellulose synthase complexes from the plasma membrane and results in the accumulation of these particles in a small microtubule-associated compartment. The results provide new and clear evidence for thaxtomin A having a strong impact on cellulose synthesis, thus suggesting that this is its primary mode of action.

  5. 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.

  6. 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.

  7. Host specificity in Sporisorium reilianum is determined by distinct mechanisms in maize and sorghum.

    Science.gov (United States)

    Poloni, Alana; Schirawski, Jan

    2016-06-01

    Smut fungi are biotrophic plant pathogens that exhibit a very narrow host range. The smut fungus Sporisorium reilianum exists in two host-adapted formae speciales: S. reilianum f. sp. reilianum (SRS), which causes head smut of sorghum, and S. reilianum f. sp. zeae (SRZ), which induces disease on maize. It is unknown why the two formae speciales cannot form spores on their respective non-favoured hosts. By fungal DNA quantification and fluorescence microscopy of stained plant samples, we followed the colonization behaviour of both SRS and SRZ on sorghum and maize. Both formae speciales were able to penetrate and multiply in the leaves of both hosts. In sorghum, the hyphae of SRS reached the apical meristems, whereas the hyphae of SRZ did not. SRZ strongly induced several defence responses in sorghum, such as the generation of H2 O2 , callose and phytoalexins, whereas the hyphae of SRS did not. In maize, both SRS and SRZ were able to spread through the plant to the apical meristem. Transcriptome analysis of colonized maize leaves revealed more genes induced by SRZ than by SRS, with many of them being involved in defence responses. Amongst the maize genes specifically induced by SRS were 11 pentatricopeptide repeat proteins. Together with the microscopic analysis, these data indicate that SRZ succumbs to plant defence after sorghum penetration, whereas SRS proliferates in a relatively undisturbed manner, but non-efficiently, on maize. This shows that host specificity is determined by distinct mechanisms in sorghum and maize.

  8. 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.

  9. Silicon and the plant extracellular matrix

    Directory of Open Access Journals (Sweden)

    Gea eGuerriero

    2016-04-01

    Full Text Available Silicon (Si is one of the most abundant elements on earth. Although not considered essential for the growth and development of higher plants, it is nonetheless known to increase vigour and to play protective roles. Its protective effects include for instance alleviation of (abiotic stress damages and heavy metal toxicity. Si was shown to interact with several components of the plant cell walls in the form of silica (SiO2. In plants SiO2 promotes strengthening of the cell walls and provides increased mechanical support to the aerial parts. The relationship SiO2-plant cell wall has been well documented in monocots and pteridophytes, which are known Si accumulators, while much less is known on the interaction of Si with the cell walls of dicots. We here provide a concise up-to-date survey on the interaction between Si and plant cell wall components by focussing on cellulose, hemicelluloses, callose, pectins, lignin and proteins. We also describe the effects of Si on cell wall-related processes by discussing the published results in both monocots and dicots. We conclude our survey with a description of the possible mechanisms by which Si exerts priming in plants.

  10. 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.)

  11. Molecular and structural changes induced by essential oils treatments in Vicia faba roots detected by genotoxicity testing.

    Science.gov (United States)

    Sturchio, Elena; Boccia, Priscilla; Zanellato, Miriam; Meconi, Claudia; Donnarumma, Lucia; Mercurio, Giuseppe; Mecozzi, Mauro

    2016-01-01

    Over the last few years, there has been an increased interest in exploiting allelopathy in organic agriculture. The aim of this investigation was to examine the effects of essential oil mixtures in order to establish their allelopathic use in agriculture. Two mixtures of essential oils consisting respectively of tea tree oil (TTO) and clove plus rosemary (C + R) oils were tested. Phytotoxicity and genotoxicity tests on the root meristems of Vicia faba minor were performed. A phytotoxic influence was particularly relevant for C + R mixture, while genotoxicity tests revealed significant results with both C + R oil mixture and TTO. Phenotypic analysis on Vicia faba minor primary roots following C + R oil mixture treatment resulted in callose production, an early symptom attributed to lipid peroxidation. The approach described in this study, based on genotoxicity bioassays, might identify specific DNA damage induced by essential oil treatments. These tests may represent a powerful method to evaluate potential adverse effects of different mixtures of essential oils that might be useful in alternative agriculture. Future studies are focusing on the positive synergism of more complex mixtures of essential oils in order to reduce concentrations of potentially toxic components while at the same time maintaining efficacy in antimicrobial and antifungal management.

  12. 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.

  13. Functional Topography of Human Corpus Callosum: An fMRI Mapping Study

    Directory of Open Access Journals (Sweden)

    Mara Fabri

    2013-01-01

    Full Text Available The concept of a topographical map of the corpus callosum (CC has emerged from human lesion studies and from electrophysiological and anatomical tracing investigations in other mammals. Over the last few years a rising number of researchers have been reporting functional magnetic resonance imaging (fMRI activation in white matter, particularly the CC. In this study the scope for describing CC topography with fMRI was explored by evoking activation through simple sensory stimulation and motor tasks. We reviewed our published and unpublished fMRI and diffusion tensor imaging data on the cortical representation of tactile, gustatory, auditory, and visual sensitivity and of motor activation, obtained in 36 normal volunteers and in 6 patients with partial callosotomy. Activation foci were consistently detected in discrete CC regions: anterior (taste stimuli, central (motor tasks, central and posterior (tactile stimuli, and splenium (auditory and visual stimuli. Reconstruction of callosal fibers connecting activated primary gustatory, motor, somatosensory, auditory, and visual cortices by diffusion tensor tracking showed bundles crossing, respectively, through the genu, anterior and posterior body, and splenium, at sites harboring fMRI foci. These data confirm that the CC commissure has a topographical organization and demonstrate that its functional topography can be explored with fMRI.

  14. Preserved Transcallosal Inhibition to Transcranial Magnetic Stimulation in Nondemented Elderly Patients with Leukoaraiosis

    Directory of Open Access Journals (Sweden)

    Giuseppe Lanza

    2013-01-01

    Full Text Available Structural corpus callosum (CC changes in patients with leukoaraiosis (LA are significantly associated with cognitive and motor impairment. The aim of this study is to investigate the transcallosal fibers functioning by means of transcranial magnetic stimulation (TMS in elderly patients with LA. The resting motor threshold (rMT, the motor-evoked potentials (MEPs, and the controlateral (cSP and ipsilateral silent periods (iSP were determined using single-pulse TMS in 15 patients and 15 age-matched controls. The neuropsychological profile and the vascular burden at brain magnetic resonance imaging (MRI were concomitantly explored. Patients reported abnormal scores at tests evaluating executive control functions. No significant difference was found in TMS measures of intra- and intercortical excitability. No CC lesion was evident at MRI. Transcallosal inhibitory mechanisms to TMS seem to be spared in LA patients, a finding which is in line with neuroimaging features and suggests a functional integrity of the CC despite the ischemic interruption of corticosubcortical loops implicated in cognition and behavior. The observed neurophysiological finding differs from that reported in degenerative dementia, even in the preclinical or early stage. In our group of patients, the pure extent of LA is more related to impairment of frontal lobe abilities rather than functional callosal changes.

  15. Anomalous pollen grain development after nondifferentiating microspore division in Eremurus

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    M. Charzyńska

    2015-01-01

    Full Text Available Anomalous pollen grain development in Eremurus is caused by an anomalous position of the mitotic spindle and microspore protoplast division into two cells different than in differentiating division. The nuclei of the abnormal gametophytes are always spherical and that of the smaller of the two cells, notwithstanding the shape and position of the latter, has a more compact structure resembling rather that of the generative cell nucleus. Binucleate abnormal gametophytes always have equal nuclei. The wall separating the cells in abnormal pollen grains at first contains callose and, after disappearance of the latter, probably pectins and cellulose. Abnormal pollen grains contain less cytoplasmic RNA than normal ones arid most of them degenerate. If their viability is preserved they do not form' normal pollen tubes in vitro. The frequency of anomalous microspore division is higher in E. robustus (max ca. 50% than in E. himalaicus (max. ca. 30% and shows considerable seasonal variations. The results obtained suggest that disturbances in microspore development in Eremurus have a genetic background, but are stimulated by temperature variations in the period preceding mitosis in the microspore.

  16. [Effects of callosotomy in the treatment of intractable epilepsies in children on psychiatric disorders].

    Science.gov (United States)

    Septien, L; Giroud, M; Sautreaux, J L; Brenot, M; Marin, A; Dumas, R; Nivelon, J L

    1992-01-01

    Two children, 13 and 14 years old, presented an intractable epilepsy of Lennox-Gastaut. In front of dangerous tonic and atonic epileptic crisis, a corpus callosotomy was performed. Corpus callosotomy is becoming a more widely used procedure in the treatment of intractable epilepsy as Lennox-Gastaut syndrome, or frontal epilepsy. However, there have been very few series that have reported results in children. It is not a complete but a partial, callosal section including approximately the anterior two thirds of the callosum. After this surgery the two children improved dramatically because the dangerous tonic and atonic crisis disappeared. Secondly we observed improvement of pre-surgical psychiatric troubles, that is a data not developed in the literature. Before surgery, the two children had a frontal syndrome with hyperkinesia, distractibility, aggressiveness, alexithymia, loss of the program of ideas. During the two months after the section of the anterior two thirds of the corpus callosum, we observed a progressive improvement of the frontal syndrome, with possibility to learn new praxies. The intellectual quotient was not altered and associative functions, depending of the posterior third of the corpus callosum were spared. Anti-epileptic medications were not stopped. We think that the improvement of the frontal syndrome is due to reduction of seizures. Therefore, we insist on the interest of the section of the anterior two thirds of the corpus callosum as treatment of tonic and atonic seizures but also as treatment of psychiatric symptoms depending of a frontal syndrome.

  17. Defense/stress responses activated by chitosan in sycamore cultured cells.

    Science.gov (United States)

    Malerba, Massimo; Crosti, Paolo; Cerana, Raffaella

    2012-01-01

    Chitosan (CHT) is a natural, non-toxic, and inexpensive compound obtained by partial alkaline deacetylation of chitin, the main component of the exoskeleton of crustaceans and other arthropods. The unique physiological and biological properties of CHT make this polymer useful for a wide range of industries. In agriculture, CHT is used to control numerous pre- and postharvest diseases on various horticultural commodities. In recent years, much attention has been devoted to CHT as an elicitor of defense responses in plants, which include raising of cytosolic Ca(2+), activation of MAP kinases, callose apposition, oxidative burst, hypersensitive response, synthesis of abscisic acid, jasmonate, phytoalexins, and pathogenesis-related proteins. In this work, we investigated the effects of different CHT concentrations on some defense/stress responses of sycamore (Acer pseudoplatanus L.) cultured cells. CHT induced accumulation of dead cells, and of cells with fragmented DNA, production of H(2)O(2) and nitric oxide, release of cytochrome c from the mitochondrion, accumulation of regulative 14-3-3 proteins in the cytosol and of HSP70 molecular chaperone binding protein in the endoplasmic reticulum, accompanied by marked modifications in the architecture of this cell organelle.

  18. Characters related to higher starch accumulation in cassava storage roots.

    Science.gov (United States)

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-01-01

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed.

  19. 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.

  20. 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.)

  1. 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.

  2. 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.

  3. Reversible Restricted Diffusion in the Corpus Callosum in Various Pediatric Diseases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Kyung; Hong, Hyun Sook; Lee, A Leum; Cha, Jang Gyu; Lee, Hae Kyung [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Bae, Won Kyung [Dept. of Radiology, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan (Korea, Republic of)

    2012-04-15

    To evaluate the reversible restricted diffusion in the corpus callosum in pediatric patients with clinical findings, and to discuss the possible pathogenesis of these lesions. Between 2007 and 2011, seven children with reversible signal abnormalities in the corpus callosum were identified and retrospectively reviewed. Diseases and conditions associated with lesions included: trauma (n = 3), neonatal seizure (n = 1), clinically suspected mild encephalopathy (n = 1), multiple sclerosis (n = 1), and seizure with subdural hygroma (n = 1). The callosal lesions were located in the splenium and the genu (n = 2), the splenium and the body (n = 1), and the splenium only (n 4). The shape of the lesions was round-to-ovoid (n = 4) or linear (n = 3). Follow-up MRI scans showed completely resolved (n = 6) or persistent (n = 1) signal abnormalities on diffusion-weighted imaging as well as apparent diffusion coefficient mapping. Clinical outcomes were good in six of the patents but poor in the seventh. Reversible restricted diffusion in the corpus callosum can develop in various diseases. Knowledge of the MRI findings and associated diseases might be helpful in predicting patients' conditions and clinical outcomes.

  4. LESSER METATARSAL SESAMOIDITIS-POTENTIAL CAUSE OF FORE FOOT PAIN?? : A PROSPECTIVE MULTICENTER EPIDEMIOLOGICAL SCREENING STUDY OF THE ODISHA POPULATION

    Directory of Open Access Journals (Sweden)

    Sunil Kumar

    2014-11-01

    Full Text Available INTRODUCTION: Sesamoiditis as a cause of fore foot pain is less often thought of, patients suffer for extended periods due to misdiagnosis and analgesic abuse resulting in dissatisfaction, depression and anxiety. METHODS: We performed a multicenter prospective epidemiological screening study in Bhubaneswar, Odisha from Nov’ 2013 to July’ 2014 in patients of foot pain for the presence of lesser sesamoids to study the incidences and causes of fore foot pain in Odisha Population. RESULTS: We screened 960 patients (1920 feet in 500 male and 460 female patients. 5th Metatarsal sesamoids were present in 77 (8% patients (M/F: 1.8:1, Bilateral in 67 (86 % patients. (48% patients lesser sesamoids were bipartite and (82% were symptomatic. 52% recovered with conservative measures, 40 % patients required ultrasound guided injections and sesamoidectomy was performed in 8 % patients due to recurrence and/or failure. Other causes of fore foot pain were Rheumatoid Arthritis, Gouty Arthritis, Callosities, Hallux Valgus, Stress Fractures of the Metatarsals, Plantar Fasciitis, Infections, Morton’s Metatarsalgia and Barefoot Walking (mechanical. DISCUSSION: High incidences of lesser sesamoids is attributed to genetics, low socioeconomic status, bare foot walking and high prevalence of Diabetes Mellitus, Smoking and Gout in our country. CT and MRI provide useful information regarding the presence and pathology involving these bones, and should be used in concert with clinical findings to guide successful patient management. An initial trial of conservative measures should follow minimally invasive ultrasound guided injections of anesthetic with steroids and lastly surgical excision.

  5. Verbal dichotic listening in right and left-handed adults: laterality effects of directed attention.

    Science.gov (United States)

    Foundas, Anne L; Corey, David M; Hurley, Megan M; Heilman, Kenneth M

    2006-01-01

    Dichotic listening performance of consonant vowel stimuli was studied in 51 adult right- and left-handers in three attention conditions: non-directed and directed to either the right or left ear. In the non-directed condition, a significant right-ear advantage was found in both handedness groups with a stronger asymmetry in right-handers. There are at least three explanations for this ear bias. The classic or structural hypothesis suggests that to the right ear projects more strongly to the language dominant left hemisphere. The callosal relay hypothesis is based on the influence of inhibitory connections via the corpus callosum. The attentional hypothesis suggests that each hemisphere primarily directs attention to contralateral space and because the left hemisphere is dominant for language in both groups, and is aroused by speech stimuli, attention is primarily directed to the right ear. Neither hypothesis can explain why greater than 95% of right-handers have left hemisphere language dominance, but only 70-80% have a right ear bias. Our results demonstrate that in the directed attention conditions both groups increased their lateral biases when directed to either the right or left. The classic or structural hypothesis cannot account for these changes, thereby providing support for the attentional hypothesis. In addition, the right-handed subjects exhibited a greater shift of bias than did the left-handed subjects, when directing their attention leftward. This finding suggests that right-handed people are better able to shift their attention than left-handed people.

  6. 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.

  7. Learning a unimanual motor skill by partial commissurotomy patients.

    Science.gov (United States)

    Chen, Y P; Campbell, R; Marshall, J C; Zaidel, D W

    1990-09-01

    A series of motor tests on four Chinese partial commissurotomy patients is reported. The single-stage commissurotomy in all four patients included the anterior commissures and two-thirds or four-fifths section of the corpus callosum with sparing of the splenium. There was no demonstrable ability to transfer hand posture in these patients. This was the major evidence for functional deconnexion. A newly learned task of one-hand knotting revealed right hand impairment in all four patients. There was no dyspraxia in the right hand for over-learned object-handling tasks in these patients. It is suggested that there might be right hemisphere specialisation for the initial acquisition of unimanual object-handling skills and that the spared callosal fibres in the splenium alone are insufficient to mediate task control under these conditions. This is supported by the finding that one of these patients, who was the only one who had a right parietal lesion, was unable to perform the newly learned task with either hand.

  8. 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.

  9. Cognitive Control Network Contributions to Memory-Guided Visual Attention.

    Science.gov (United States)

    Rosen, Maya L; Stern, Chantal E; Michalka, Samantha W; Devaney, Kathryn J; Somers, David C

    2016-05-01

    Visual attentional capacity is severely limited, but humans excel in familiar visual contexts, in part because long-term memories guide efficient deployment of attention. To investigate the neural substrates that support memory-guided visual attention, we performed a set of functional MRI experiments that contrast long-term, memory-guided visuospatial attention with stimulus-guided visuospatial attention in a change detection task. Whereas the dorsal attention network was activated for both forms of attention, the cognitive control network(CCN) was preferentially activated during memory-guided attention. Three posterior nodes in the CCN, posterior precuneus, posterior callosal sulcus/mid-cingulate, and lateral intraparietal sulcus exhibited the greatest specificity for memory-guided attention. These 3 regions exhibit functional connectivity at rest, and we propose that they form a subnetwork within the broader CCN. Based on the task activation patterns, we conclude that the nodes of this subnetwork are preferentially recruited for long-term memory guidance of visuospatial attention.

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

    Science.gov (United States)

    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.

  11. Cytoarchitecture of mouse and rat cingulate cortex with human homologies.

    Science.gov (United States)

    Vogt, Brent A; Paxinos, George

    2014-01-01

    A gulf exists between cingulate area designations in human neurocytology and those used in rodent brain atlases with a major underpinning of the former being midcingulate cortex (MCC). The present study used images extracted from the Franklin and Paxinos mouse atlas and Paxinos and Watson rat atlas to demonstrate areas comprising MCC and modifications of anterior cingulate (ACC) and retrosplenial cortices. The laminar architecture not available in the atlases is also provided for each cingulate area. Both mouse and rat have a MCC with neurons in all layers that are larger than in ACC and layer Va has particularly prominent neurons and reduced neuron densities. An undifferentiated ACC area 33 lies along the rostral callosal sulcus in rat but not in mouse and area 32 has dorsal and ventral subdivisions with the former having particularly large pyramidal neurons in layer Vb. Both mouse and rat have anterior and posterior divisions of retrosplenial areas 29c and 30, although their cytology is different in rat and mouse. Maps of the rodent cingulate cortices provide for direct comparisons with each region in the human including MCC and it is significant that rodents do not have a posterior cingulate region composed of areas 23 and 31 like the human. It is concluded that rodents and primates, including humans, possess a MCC and this homology along with those in ACC and retrosplenial cortices permit scientists inspired by human considerations to test hypotheses on rodent models of human diseases.

  12. Concomitant fractional anisotropy and volumetric abnormalities in temporal lobe epilepsy: cross-sectional evidence for progressive neurologic injury.

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    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.

  13. 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.

  14. 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.

  15. Pediatric Balint's Syndrome Variant: A Possible Diagnosis in Children

    Science.gov (United States)

    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. PMID:27895948

  16. Determining the Subcellular Location of Synthesis and Assembly of the Cell Wall Polysaccharide (1,3; 1,4)-β-d-Glucan in Grasses[OPEN

    Science.gov (United States)

    Wilson, Sarah M.; Ho, Yin Ying; Lampugnani, Edwin R.; Van de Meene, Allison M.L.; Bain, Melissa P.; Bacic, Antony; Doblin, Monika S.

    2015-01-01

    The current dogma for cell wall polysaccharide biosynthesis is that cellulose (and callose) is synthesized at the plasma membrane (PM), whereas matrix phase polysaccharides are assembled in the Golgi apparatus. We provide evidence that (1,3;1,4)-β-d-glucan (mixed-linkage glucan [MLG]) does not conform to this paradigm. We show in various grass (Poaceae) species that MLG-specific antibody labeling is present in the wall but absent over Golgi, suggesting it is assembled at the PM. Antibodies to the MLG synthases, cellulose synthase-like F6 (CSLF6) and CSLH1, located CSLF6 to the endoplasmic reticulum, Golgi, secretory vesicles, and the PM and CSLH1 to the same locations apart from the PM. This pattern was recreated upon expression of VENUS-tagged barley (Hordeum vulgare) CSLF6 and CSLH1 in Nicotiana benthamiana leaves and, consistent with our biochemical analyses of native grass tissues, shown to be catalytically active with CSLF6 and CSLH1 in PM-enriched and PM-depleted membrane fractions, respectively. These data support a PM location for the synthesis of MLG by CSLF6, the predominant enzymatically active isoform. A model is proposed to guide future experimental approaches to dissect the molecular mechanism(s) of MLG assembly. PMID:25770111

  17. Sincipital Encephaloceles: A Study of Associated Brain Malformations

    Directory of Open Access Journals (Sweden)

    Shashidhar Vedavyas Achar

    2016-01-01

    Full Text Available Objective: The aim of this study was to evaluate the associated intracranial malformations in patients with sincipital encephaloceles. Materials and Methods: A hospital-based cross-sectional study was conducted over 8 years from June 2007 to May 2015 on 28 patients. The patients were evaluated by either computed tomography or magnetic resonance imaging whichever was feasible. Encephaloceles were described with respect to their types, contents, and extensions. A note was made on the associated malformations with sincipital encephaloceles. Results: Fifty percent of the patients presented before the age of 3 years and both the sexes were affected equally. Nasofrontal encephalocele was the most common type seen in 13 patients (46.4%, and corpus callosal agenesis (12 patients was the most common associated malformation. Other malformations noted were arachnoid cyst (10 patients, hydrocephalus (7 patients, and agyria-pachygyria complex (2 patients. Conclusion: Capital Brain malformations are frequently encountered in children with sincipital encephaloceles. Detail radiological evaluation is necessary to plan treatment and also to prognosticate such rare malformations.

  18. Intracranial lipomas. Case presentations and CT features

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Takashi; Shojima, Kazuhito; Moritaka, Kazuhiko; Utsunomiya, Hidetsuna; Konishi, Jun (St. Mary' s Hospital, Kurume, Fukuoka (Japan))

    1984-03-01

    Intracranial lipomas are very rare and reports of infantile lipomas are scarce. Nine cases of intracranial lipomas, five in infants and four in adults are described and characteristic findings of the CT are presented. Two of the six cases involved lipomas at the corpus callosum that were associated with frontal dysraphism and cranium bifidum at the midline of frontal region. Five of the nine cases involved lipomas at the quadrigeminal cistern. In one case with an advanced enlargement in circumference of the head in the perinatal period, a V-P shunt was conducted for obstructive hydrocephalus. Another case had widely ranging agenesis of the corpus callosum associated with an interhemispheric cyst showing the right sided parietal and occipital lobes through the callosal agenesis. One of the nine cases had a lipoma in the left sylvian fissure and in the adult was in the interpeduncular cistern. Four of the nine cases were associated with agenesis of the corpus callosum. Based on these cases and published reports, the CT features of intracranial lipoma are discussed.

  19. Axonal pathfinding mechanisms at the cortical midline and in the development of the corpus callosum

    Directory of Open Access Journals (Sweden)

    Richards L.J.

    2002-01-01

    Full Text Available The corpus callosum is a large fiber tract that connects neurons in the right and left cerebral hemispheres. Agenesis of the corpus callosum (ACC is associated with a large number of human syndromes but little is known about why ACC occurs. In most cases of ACC, callosal axons are able to grow toward the midline but are unable to cross it, continuing to grow into large swirls of axons known as Probst bundles. This phenotype suggests that in some cases ACC may be due to defects in axonal guidance at the midline. General guidance mechanisms that influence the development of axons include chemoattraction and chemorepulsion, presented by either membrane-bound or diffusible molecules. These molecules are not only expressed by the final target but by intermediate targets along the pathway, and by pioneering axons that act as guides for later arriving axons. Midline glial populations are important intermediate targets for commissural axons in the spinal cord and brain, including the corpus callosum. The role of midline glial populations and pioneering axons in the formation of the corpus callosum are discussed. Finally the differential guidance of the ipsilaterally projecting perforating pathway and the contralaterally projecting corpus callosum is addressed. Development of the corpus callosum involves the coordination of a number of different guidance mechanisms and the probable involvement of a large number of molecules.

  20. Mental State Understanding in Children with Agenesis of the Corpus Callosum.

    Science.gov (United States)

    Lábadi, Beatrix; Beke, Anna M

    2017-01-01

    Impaired social functioning is a well-known outcome of individuals with agenesis of the corpus callosum. Social deficits in nonliteral language comprehension, humor, social reasoning, and recognition of facial expression have all been documented in adults with agenesis of the corpus callosum. In the present study, we examined the emotional and mentalizing deficits that contributing to the social-cognitive development in children with isolated corpus callosum agenesia, including emotion recognition, theory of mind, executive function, working memory, and behavioral impairments as assessed by the parents. The study involved children between the age of 6 and 8 years along with typically developing children who were matched by IQ, age, gender, education, and caregiver's education. The findings indicated that children with agenesis of the corpus callosum exhibited mild impairments in all social factors (recognizing emotions, understanding theory of mind), and showed more behavioral problems than control children. Taken together, these findings suggest that reduced callosal connectivity may contribute to the development of higher-order social-cognitive deficits, involving limits of complex and rapidly occurring social information to be processed. The studies of AgCC shed lights of the role of structural connectivity across the hemispheres in neurodevelopmental disorders.

  1. Independent and collaborative contributions of the cerebral hemispheres to emotional processing

    Directory of Open Access Journals (Sweden)

    Elizabeth R Shobe

    2014-04-01

    Full Text Available Presented is a model suggesting that the RH directly mediates the identification and comprehension of positive and negative emotional stimuli, whereas the LH contributes to higher level processing of emotional information that has been shared via the corpus callosum. RH subcortical connections provide initial processing of emotional stimuli, and their innervation to cortical structures provides a secondary pathway by which the hemispheres process emotional information more fully. It is suggested that the LH contribution to emotion processing is in emotional regulation, social well-being and adaptation, and transforming the RH emotional experience into propositional and verbal codes. Lastly, it is proposed that the LH has little ability at the level of emotion identification, having a default positive bias and no ability to identify a stimulus as negative. Instead, the LH must rely on the transfer of emotional information from the RH to engage higher order emotional processing. As such, either hemisphere can identify positive emotions, but they must collaborate for complete processing of negative emotions. Evidence presented draws from behavioral, neurological, and clinical research, including discussions of subcortical and cortical pathways, callosal agenesis, commissurototomy, emotion regulation, mood disorders, interpersonal interaction, language, and handedness. Directions for future research are offered.

  2. Self-sterility in Camellia oleifera may be due to the prezygotic late-acting self-incompatibility.

    Directory of Open Access Journals (Sweden)

    Ting Liao

    Full Text Available In this report, self-sterility in Camellia oleifera was explored by comparing structural and statistical characteristics following self-pollination (SP and cross-pollination (CP. Although slightly delayed pollen germination and pollen tube growth in selfed ovaries compared to crossed ovaries was observed, there was no significant difference in the percentages of pollen that germinated and pollen tubes that grew to the base of the style. There was also no difference in morphological structure after the two pollination treatments. However, the proportions of ovule penetration and double fertilization in selfed ovules were significantly lower than in crossed ovules, indicating that a prezygotic late-acting self-incompatible mechanism may exist in C. oleifera. Callose deposition was observed in selfed abortive ovules, but not in normal. Ovules did not show differences in anatomic structure during embryonic development, whereas significant differences were observed in the final fruit and seed set. In addition, aborted ovules in selfed ovaries occurred within 35 days after SP and prior to zygote division. However, this process did not occur continuously throughout the life cycle, and no zygotes were observed in the selfed abortive ovules. These results indicated that the self-sterility in C. oleifera may be caused by prezygotic late-acting self-incompatibility (LSI.

  3. Refractory High Intracranial Pressure following Intraventricular Hemorrhage due to Moyamoya Disease in a Pregnant Caucasian Woman

    Science.gov (United States)

    Montiel, Virginie; Grandin, Cécile; Goffette, Pierre; Fomekong, Edward; Hantson, Philippe

    2009-01-01

    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. PMID:20508823

  4. http://www.revistas.unal.edu.co/index.php/biotecnologia/article/view/54277

    Directory of Open Access Journals (Sweden)

    Diana Lorena García Lozano

    2015-11-01

    Full Text Available Aspidosperma polyneuron is a species native to the Neotropics, in countries like Colombia, Venezuela, Peru, Brazil, Argentina and Paraguay, typical of semi-deciduous forests, catalogued since 1998 by the IUCN as "Endangered (EN", because its natural populations were subjected to an intense exploitation for timber and its habitat was seriously degraded by agricultural and silvopastoral activities. The difficulties for its natural regeneration and the rooting of cuttings, make the in vitro culture an efficient tool to counteract the reproductive difficulties that it presents. However, the presence of pollutants that affect the viability of the explants needs the development of protocols that allow the in vitro establishment of this species. The objective of this research was to achieve aseptic establishment and the induction of callogenesis in explants of A. polyneuron, by evaluating different disinfection treatments. The expants were obtained from individuals of natural regeneration, in the Municipality of Armero in the Department of Tolima, which were immersed in distilled water with a drop of Tween® 80 for each 100 ml, for 10 minutes and then rinsed with sterile distilled water. There were used as disinfectant agents, sodium hypochlorite and mercury dichloride in different concentrations and times of immersion. Among the used explants: buds, nodal segments and leaf blades, the last one was selected for its capacity of producing friable and green callosity, for which a disinfection with mercury dichloride (HgCl2 0.125% for 10 minutes was enough for contamination control and low indexes of oxidation.

  5. Input and output gain modulation by the lateral interhemispheric network in early visual cortex.

    Science.gov (United States)

    Wunderle, Thomas; Eriksson, David; Peiker, Christiane; Schmidt, Kerstin E

    2015-05-20

    Neurons in the cerebral cortex are constantly integrating different types of inputs. Dependent on their origin, these inputs can be modulatory in many ways and, for example, change the neuron's responsiveness, sensitivity, or selectivity. To investigate the modulatory role of lateral input from the same level of cortical hierarchy, we recorded in the primary visual cortex of cats while controlling synaptic input from the corresponding contralateral hemisphere by reversible deactivation. Most neurons showed a pronounced decrease in their response to a visual stimulus of different contrasts and orientations. This indicates that the lateral network acts via an unspecific gain-setting mechanism, scaling the output of a neuron. However, the interhemispheric input also changed the contrast sensitivity of many neurons, thereby acting on the input. Such a contrast gain mechanism has important implications because it extends the role of the lateral network from pure response amplification to the modulation of a specific feature. Interestingly, for many neurons, we found a mixture of input and output gain modulation. Based on these findings and the known physiology of callosal connections in the visual system, we developed a simple model of lateral interhemispheric interactions. We conclude that the lateral network can act directly on its target, leading to a sensitivity change of a specific feature, while at the same time it also can act indirectly, leading to an unspecific gain setting. The relative contribution of these direct and indirect network effects determines the outcome for a particular neuron.

  6. Surgical therapy by sandwich transplantation using a dermal collagen-elastin matrix and full thickness split grafts and gait rehabilitation with individualized orthesis

    Directory of Open Access Journals (Sweden)

    Uwe Wollina

    2012-01-01

    Full Text Available Painful callosities of the feet (PCOF are a rare complaint in children with severe impairment of mobility and quality of life. There is no medical treatment available.We investigated the usefulness of a recently developed combined transplant technique-the sandwich transplantation with dermal collagen-elastin template in this rare condition. A 14-year-old boy suffered from PCOF for several years without any improvement by topical therapy, dermabrasion, and oral retinoids. He was unable to walk normally and suffered from severe pain. We performed a complete deep excision of the hyperkeratotic plantar tissue in general anaesthesia in combination with sandwich transplantation in the same setting. Dry sheets of collagen-elastin matrix (1 mm thickness were placed on the soft tissue defects and covered by full-thickness mesh graft transplants from the upper leg. An individualized orthosis was produced for gait rehabilitation. Two weeks after surgery the gait-related pain was reduced remarkably. Using the orthosis, the boy was able to walk pain-free even on staircase. Surgery of PCOF with sandwich transplantation and gait rehabilitation appears to be a promising strategy for this rare condition.

  7. Altered Interhemispheric Functional Coordination in Chronic Tinnitus Patients

    Directory of Open Access Journals (Sweden)

    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.

  8. Nitrate reductase-mediated early nitric oxide burst alleviates oxidative damage induced by aluminum through enhancement of antioxidant defenses in roots of wheat (Triticum aestivum).

    Science.gov (United States)

    Sun, Chengliang; Lu, Lingli; Liu, Lijuan; Liu, Wenjing; Yu, Yan; Liu, Xiaoxia; Hu, Yan; Jin, Chongwei; Lin, Xianyong

    2014-03-01

    • Nitric oxide (NO) is an important signaling molecule involved in the physiological processes of plants. The role of NO release in the tolerance strategies of roots of wheat (Triticum aestivum) under aluminum (Al) stress was investigated using two genotypes with different Al resistances. • An early NO burst at 3 h was observed in the root tips of the Al-tolerant genotype Jian-864, whereas the Al-sensitive genotype Yang-5 showed no NO accumulation at 3 h but an extremely high NO concentration after 12 h. Stimulating NO production at 3 h in the root tips of Yang-5 with the NO donor relieved Al-induced root inhibition and callose production, as well as oxidative damage and ROS accumulation, while elimination of the early NO burst by NO scavenger aggravated root inhibition in Jian-864. • Synthesis of early NO in roots of Jian-864 was mediated through nitrate reductase (NR) but not through NO synthase. Elevated antioxidant enzyme activities were induced by Al stress in both wheat genotypes and significantly enhanced by NO donor, but suppressed by NO scavenger or NR inhibitor. • These results suggest that an NR-mediated early NO burst plays an important role in Al resistance of wheat through modulating enhanced antioxidant defense to adapt to Al stress.

  9. 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.

  10. Mental State Understanding in Children with Agenesis of the Corpus Callosum

    Science.gov (United States)

    Lábadi, Beatrix; Beke, Anna M.

    2017-01-01

    Impaired social functioning is a well-known outcome of individuals with agenesis of the corpus callosum. Social deficits in nonliteral language comprehension, humor, social reasoning, and recognition of facial expression have all been documented in adults with agenesis of the corpus callosum. In the present study, we examined the emotional and mentalizing deficits that contributing to the social-cognitive development in children with isolated corpus callosum agenesia, including emotion recognition, theory of mind, executive function, working memory, and behavioral impairments as assessed by the parents. The study involved children between the age of 6 and 8 years along with typically developing children who were matched by IQ, age, gender, education, and caregiver's education. The findings indicated that children with agenesis of the corpus callosum exhibited mild impairments in all social factors (recognizing emotions, understanding theory of mind), and showed more behavioral problems than control children. Taken together, these findings suggest that reduced callosal connectivity may contribute to the development of higher-order social-cognitive deficits, involving limits of complex and rapidly occurring social information to be processed. The studies of AgCC shed lights of the role of structural connectivity across the hemispheres in neurodevelopmental disorders. PMID:28220087

  11. Action of Multiple Cell Wall-Degrading Enzymes Is Required for Elicitation of Innate Immune Responses During Xanthomonas oryzae pv. oryzae Infection in Rice.

    Science.gov (United States)

    Tayi, Lavanya; Maku, Roshan; Patel, Hitendra Kumar; Sonti, Ramesh V

    2016-08-01

    Xanthomonas oryzae pv. oryzae secretes a number of plant cell wall-degrading enzymes (CWDEs) whose purified preparations induce defense responses in rice. These defense responses are suppressed by X. oryzae pv. oryzae using type 3 secretion system (T3SS) effectors and a type 3 secretion system mutant (T3SS(-)) of X. oryzae pv. oryzae is an inducer of rice defense responses. We assessed the role of individual CWDEs in induction of rice defense responses during infection, by mutating them in the genetic background of a T3SS(-). We mutated the genes for five different plant CWDEs secreted by X. oryzae pv. oryzae, including two cellulases (clsA and cbsA), one xylanase (xyn), one pectinase (pglA), and an esterase (lipA), singly in a T3SS(-) background. We have demonstrated that, as compared with a T3SS(-) of X. oryzae pv. oryzae, a cbsA(-)T3SS(-), a clsA(-)T3SS(-), and a xyn(-)T3SS(-) are deficient in induction of rice immune responses such as callose deposits and programmed cell death. In comparison, a lipA(-) T3SS(-) and a pglA(-)T3SS(-) is as efficient in induction of host defense responses as a T3SS(-). Overall, these results indicate that the collective action of X. oryzae pv. oryzae-secreted ClsA, CbsA, and Xyn proteins is required for induction of rice defense responses during infection.

  12. Identification of plant defence regulators through transcriptional profiling of Arabidopsis thaliana cdd1 mutant

    Indian Academy of Sciences (India)

    Swadhin Swain; Nidhi Singh; Ashis Kumar Nandi

    2015-03-01

    A sustainable balance between defence and growth is essential for optimal fitness under pathogen stress. Plants activate immune response at the cost of normal metabolic requirements. Thus, plants that constitutively activate defence are deprived of growth. Arabidopsis thaliana mutant constitutive defence without defect in growth and development1 (cdd1) is an exception. The cdd1 mutant is constitutive for salicylic acid accumulation, signalling, and defence against biotrophic and hemibiotrophic pathogens, without having much impact on growth. Thus, cdd1 offers an ideal genetic background to identify novel regulators of plant defence. Here we report the differential gene expression profile between cdd1 and wild-type plants as obtained by microarray hybridization. Expression of several defence-related genes also supports constitutive activation of defence in cdd1. We screened T-DNA insertion mutant lines of selected genes, for resistance against virulent bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). 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 defence against bacterial pathogens.

  13. Topographic organization of V1 projections through the corpus callosum in humans.

    Science.gov (United States)

    Saenz, M; Fine, I

    2010-10-01

    The visual cortex in each hemisphere is linked to the opposite hemisphere by axonal projections that pass through the splenium of the corpus callosum. Visual-callosal connections in humans and macaques are found along the V1/V2 border where the vertical meridian is represented. Here we identify the topography of V1 vertical midline projections through the splenium within six human subjects with normal vision using diffusion-weighted MR imaging and probabilistic diffusion tractography. Tractography seed points within the splenium were classified according to their estimated connectivity profiles to topographic subregions of V1, as defined by functional retinotopic mapping. First, we report a ventral-dorsal mapping within the splenium with fibers from ventral V1 (representing the upper visual field) projecting to the inferior-anterior corner of the splenium and fibers from dorsal V1 (representing the lower visual field) projecting to the superior-posterior end. Second, we also report an eccentricity gradient of projections from foveal-to-peripheral V1 subregions running in the anterior-superior to posterior-inferior direction, orthogonal to the dorsal-ventral mapping. These results confirm and add to a previous diffusion MRI study (Dougherty et al., 2005) which identified a dorsal/ventral mapping of human splenial fibers. These findings yield a more detailed view of the structural organization of the splenium than previously reported and offer new opportunities to study structural plasticity in the visual system.

  14. Shifting brain asymmetry: the link between meditation and structural lateralization.

    Science.gov (United States)

    Kurth, Florian; MacKenzie-Graham, Allan; Toga, Arthur W; Luders, Eileen

    2015-01-01

    Previous studies have revealed an increased fractional anisotropy and greater thickness in the anterior parts of the corpus callosum in meditation practitioners compared with control subjects. Altered callosal features may be associated with an altered inter-hemispheric integration and the degree of brain asymmetry may also be shifted in meditation practitioners. Therefore, we investigated differences in gray matter asymmetry as well as correlations between gray matter asymmetry and years of meditation practice in 50 long-term meditators and 50 controls. We detected a decreased rightward asymmetry in the precuneus in meditators compared with controls. In addition, we observed that a stronger leftward asymmetry near the posterior intraparietal sulcus was positively associated with the number of meditation practice years. In a further exploratory analysis, we observed that a stronger rightward asymmetry in the pregenual cingulate cortex was negatively associated with the number of practice years. The group difference within the precuneus, as well as the positive correlations with meditation years in the pregenual cingulate cortex, suggests an adaptation of the default mode network in meditators. The positive correlation between meditation practice years and asymmetry near the posterior intraparietal sulcus may suggest that meditation is accompanied by changes in attention processing.

  15. Congenital cerebral malformations and dysfunction in fetuses and newborns following the 2013 to 2014 Zika virus epidemic in French Polynesia.

    Science.gov (United States)

    Besnard, Marianne; Eyrolle-Guignot, Dominique; Guillemette-Artur, Prisca; Lastère, Stéphane; Bost-Bezeaud, Frédérique; Marcelis, Ludivine; Abadie, Véronique; Garel, Catherine; Moutard, Marie-Laure; Jouannic, Jean-Marie; Rozenberg, Flore; Leparc-Goffart, Isabelle; Mallet, Henri-Pierre

    2016-01-01

    We detected an unusual increase in congenital cerebral malformations and dysfunction in fetuses and newborns in French Polynesia, following an epidemic of Zika virus (ZIKV), from October 2013 to March 2014. A retrospective review identified 19 cases, including eight with major brain lesions and severe microcephaly, six with severe cerebral lesions without microcephaly and five with brainstem dysfunction without visible malformations. Imaging revealed profound neurological lesions (septal and callosal disruption, ventriculomegaly, abnormal neuronal migration, cerebellar hypoplasia, occipital pseudocysts, brain calcifications). Amniotic fluid was drawn from seven cases at gestation weeks 20 to 29. ZIKV RNA was detected by RT-PCR and infectious ZIKV isolates were obtained in four of five microcephalic, but not in two non-microcephalic cases with severe brain lesions. Medical termination of pregnancy was performed in eleven cases; two cases with brainstem dysfunction died in the first months of life; six cases are alive, with severe neurological impairment. The results show that four of seven tested fetuses with major neurological injuries were infected with ZIKV in utero. For other non-microcephalic, congenital abnormalities we were not able to prove or exclude ZIKV infection retrospectively. The unusual occurrence of brain malformations or dysfunction without microcephaly following a ZIKV outbreak needs further studies.

  16. Ear Rachis Xylem Occlusion and Associated Loss in Hydraulic Conductance Coincide with the End of Grain Filling for Wheat.

    Science.gov (United States)

    Neghliz, Hayet; Cochard, Hervé; Brunel, Nicole; Martre, Pierre

    2016-01-01

    Seed dehydration is the normal terminal event in the development of orthodox seeds and is physiologically related to the cessation of grain dry mass accumulation and crop grain yield. For a better understanding of grain dehydration, we evaluated the hypothesis that hydraulic conductance of the ear decreases during the latter stages of development and that this decrease results from disruption or occlusion of xylem conduits. Whole ear, rachis, and stem nodes hydraulic conductance and percentage loss of xylem conductivity were measured from flowering to harvest-ripeness on bread wheat (Triticum aestivum L.) cv. Récital grown under controlled environments. Flag leaf transpiration, stomatal conductance, chlorophyll content and grain and ear water potentials were also measured during grain development. We show that grain dehydration was not related with whole plant physiology and leaf senescence, but closely correlated with the hydraulic properties of the xylem conduits irrigating the grains. Indeed, there was a substantial decrease in rachis hydraulic conductance at the onset of the grain dehydration phase. This hydraulic impairment was not caused by the presence of air embolism in xylem conduits of the stem internodes or rachis but by the occlusion of the xylem lumens by polysaccharides (pectins and callose). Our results demonstrate that xylem hydraulics plays a key role during grain maturation.

  17. Modification of competence for in vitro response to Fusarium oxysporum in tomato cells. II. Effect of the integration of Agrobacterium tumefaciens genes for auxin and cytokinin synthesis.

    Science.gov (United States)

    Storti, E; Bogani, P; Bettini, P; Bittini, P; Guardiola, M L; Pellegrini, M G; Inzé, D; Buiatti, M

    1994-04-01

    We have studied the effect of a change in the endogenous hormone equilibria on the competence of tomato (Lycopersicon esculentum) cells to defend themselves against the fungal pathogen Fusarium oxysporum f. sp. lycopersici. Calluses from cvs 'Davis' and 'Red River', respectively resistant and susceptible to Fusarium and transgenic for an auxin- or cytokinin-synthesizing gene from Agrobacterium tumefaciens, were used. The integration of Agrobacterium hormone-related genes into susceptible cv 'Red River' can bring the activation of defense processes to a stable competence as assessed by the inhibition of mycelial growth in dual culture and gem-tube elongation of Fusarium conidia, the determination of callose contents, peroxidase induction and ion leakage in the presence of fusaric acid. This is particularly true when the transformation results in a change of phytohormone equilibria towards an higher cytokin in concentration. On the contrary, in resistant cv 'Davis' the inhibition of both fungal growth in dual culture and conidia germination is higher when the hormone balance is modified in favour of the auxins. No significant effect was observed for ion leakage and peroxidase induction, probably because of a constitutive overproduction of cytokinins in 'Davis' cells.

  18. The in vitro physiological phenotype of tomato resistance to Fusarium oxysporum f. sp. lycopersici.

    Science.gov (United States)

    Storti, E; Latil, C; Salti, S; Bettini, P; Bogani, P; Pellegrini, M G; Simeti, C; Molnar, A; Buiatti, M

    1992-06-01

    With the aim of dissecting host-parasite interaction processes in the system Lycopersicon aesculentum-Fusarium oxysporum f. sp. lycopersici we have isolated plant cell mutants having single-step alterations in their defense response. A previous analysis of the physiological phenotypes of mutant cell clones suggested that recognition is the crucial event for active defence, and that polysaccharide content, fungal growth inhibition, peroxidase induction in in vitro dual culture and ion leakage induced by cultural filtrates of the pathogen can be markers of resistance. In this paper we present the results of a similar analysis carried out on cell cultures from one susceptible ('Red River'), one tolerant ('UC 105') and three resistant ('Davis UC 82', 'Heinz', 'UC 90') tomato cultivars. Our data confirm that the differences in the parameters considered are correlated with resistance versus susceptibility in vivo. Therefore, these parameters can be used for early screening in selection programmes. These data, together with those obtained on isolated cell mutants, suggest that the selection in vitro for altered fungal recognition and/or polysaccharide or callose content may lead to in vivo - resistant genotypes. The data are thoroughly discussed with particular attention paid to the importance of polysaccharides in active defense initiation.

  19. Riboflavin-induced Priming for Pathogen Defense in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Shujian Zhang; Xue Yang; Maowu Sun; Feng Sun; Sheng Deng; Hansong Dong

    2009-01-01

    Riboflavin (vitamin B2) participates in a variety of redox processes that affect plant defense responses. Previously we have shown that riboflavin induces pathogen resistance in the absence of hypersensitive cell death (HCD) in plants. Herein, we report that riboflavin induces priming of defense responses in Arabidopsis thaliana toward infection by virulent Pseudomonas syringae pv. Tomato DC3000 (Pst). Induced resistance was mechanistically connected with the expression of defense response genes and cellular defense events, including H2O2 burst, HCD, and callose deposition in the plant. Riboflavin treatment and inoculation of plants with Pst were neither active but both synergized to induce defense responses. The priming process needed NPR1 (essential regulator of systemic acquired resistance) and maintenance of H2O2 burst but was independent of salicylic acid, jasmonic acid, ethylene, and abscisic acid. Our results suggest that the role of riboflavin in priming defenses is subject to a signaling process distinct from the known pathways of hormone signal transduction.

  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. Induced Systemic Resistance against Botrytis cinerea by Bacillus cereus AR156 through a JA/ET- and NPR1-Dependent Signaling Pathway and Activates PAMP-Triggered Immunity in Arabidopsis.

    Science.gov (United States)

    Nie, Pingping; Li, Xia; Wang, Shune; Guo, Jianhua; Zhao, Hongwei; Niu, Dongdong

    2017-01-01

    Induced resistance response is a potent and cost effective plant defense against pathogen attack. The effectiveness and underlying mechanisms of the suppressive ability by Bacillus cereus AR156 to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) in Arabidopsis has been investigated previously; however, the strength of induced systemic resistance (ISR) activity against Botrytis cinerea remains unknown. Here, we show that root-drench application of AR156 significantly reduces disease incidence through activation of ISR. This protection is accompanied with multilayered ISR defense response activated via enhanced accumulation of PR1 protein expression in a timely manner, hydrogen peroxide accumulation and callose deposition, which is significantly more intense in plants with both AR156 pretreatment and B. cinerea inoculation than that in plants with pathogen inoculation only. Moreover, AR156 can trigger ISR in sid2-2 and NahG mutants, but not in jar1, ein2 and npr1 mutant plants. Our results indicate that AR156-induced ISR depends on JA/ET-signaling pathway and NPR1, but not SA. Also, AR156-treated plants are able to rapidly activate MAPK signaling and FRK1/WRKY53 gene expression, both of which are involved in pathogen associated molecular pattern (PAMP)-triggered immunity (PTI). The results indicate that AR156 can induce ISR by the JA/ET-signaling pathways in an NPR1-dependent manner and involves multiple PTI components.

  2. 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.

  3. 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.

  4. Prenatal irradiation-induced brain neuropathology and cognitive impairment.

    Science.gov (United States)

    Yang, Bo; Ren, Bo Xu; Tang, Feng Ru

    2017-01-01

    Embryo/fetus is much more radiosensitive than neonatal and adult human being. The main potential effects of pre-natal radiation exposure on the human brain include growth retardation, small head/brain size, mental retardation, neocortical ectopias, callosal agenesis and brain tumor which may result in a lifetime poor quality of life. The patterns of prenatal radiation-induced effects are dependent not only on the stages of fetal development, the sensitivity of tissues and organs, but also on radiation sources, doses, dose rates. With the increased use of low dose radiation for diagnostic or radiotherapeutic purposes in recent years, combined with postnatal negative health effect after prenatal radiation exposure to fallout of Chernobyl nuclear power plant accident, the great anxiety and unnecessary termination of pregnancies after the nuclear disaster, there is a growing concern about the health effect of radiological examinations or therapies in pregnant women. In this paper, we reviewed current research progresses on pre-natal ionizing irradiation-induced abnormal brain structure changes. Subsequent postnatal neuropsychological and neurological diseases were provided. Relationship between irradiation and brain aging was briefly mentioned. The relevant molecular mechanisms were also discussed. Future research directions were proposed at the end of this paper. With limited human data available, we hoped that systematical review of animal data could relight research interests on prenatal low dose/dose rate irradiation-induced brain microanatomical changes and subsequent neurological and neuropsychological disorders.

  5. 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

    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 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. PMID:19259260

  6. Priming of plant resistance by natural compounds. Hexanoic acid as a model

    Directory of Open Access Journals (Sweden)

    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.

  7. JUMPING FROM TURTLES TO WHALES: A PLIOCENE FOSSIL RECORD DEPICTS AN ANCIENT DISPERSAL OF CHELONIBIA ON MYSTICETES

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    ALBERTO COLLARETA

    2016-05-01

    Full Text Available The barnacles included in the superfamily Coronuloidea are epizoic symbionts of various marine vertebrates (including cetaceans, sirenians, and sea turtles and other crustaceans (crabs and horseshoe crabs. Among Coronuloidea, the so-called turtle barnacles (Chelonibiidae are known from Paleogene times, whereas the whale barnacles (Coronulidae likely appeared in the late Pliocene (Piacenzian. Although a derivation from the turtle barnacles (and especially from the genus Chelonibia has been proposed, the evolutionary origin of Coronulidae remains to date obscure. In this work we reappraise a fossil record from upper Pliocene (Piacenzian marine deposits at Casenuove (Empoli municipality, Tuscany, Italy comprising various shells of Chelonibia testudinaria associated to a partial skeleton of a balaenid mysticete. Based on taphonomic and morpho-functional considerations, we discuss the hypothesis that the barnacles were hosted on the baleen whale, possibly on its callosities, which could have represented an analogous of the horny carapace of marine turtles. This record strongly suggests that the baleen whales can be added to the list of the possible hosts of the barnacles of the genus Chelonibia, thus hinting that the whale barnacles may have evolved from an ancient phase of dispersal of Chelonibia (or a similar ancestor on mysticete cetaceans.

  8. 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.

  9. 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.

  10. T2 relaxometry of brain in myotonic dystrophy

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  11. Stenogyria - not only in Chiari II malformation.

    Science.gov (United States)

    Bekiesinska-Figatowska, Monika; Duczkowska, Agnieszka; Brągoszewska, Hanna; Duczkowski, Marek; Mierzewska, Hanna

    2014-12-15

    Stenogyria, meaning multiple small compacted gyri separated by shallow sulci, is reported in the literature in association with Chiari II malformation (CM II) which in turn is reported in association with myelomeningocele (MMC). The authors present five cases of stenogyria (and other abnormalities found in CM II, like callosal hypoplasia/dysplasia, agenesis of the anterior commissure, hypoplasia of the falx cerebri) in children without the history of MMC or any other form of open spinal dysraphism. In these cases stenogyria was associated with Chiari I malformation, rhombencephalosynapsis and spina bifida. Stenogyria, which is not a true neuronal migration disorder, should not be mistaken for polymicrogyria which is also present in CM II. It is histologically different from polymicrogyria because the cortex is normally organized. Also on MRI, the general sulcal pattern is preserved in stenogyria, while it is completely distorted in polymicrogyria. The authors conclude that features traditionally attributed to CM II, like stenogyria, occur not only in the population of patients with MMC as opposed to the widely accepted theory.

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

    Science.gov (United States)

    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.

  13. 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.

  14. Electrical signalling along the phloem and its physiological responses in the maize leaf

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    Joerg eFromm

    2013-07-01

    Full Text Available To elucidate the role of electrical signalling in the phloem of maize the tips of attached leaves were stimulated by chilling and wounding. Two different signals were detected in the phloem at the middle of the leaf using the aphid stylet technique: (i action potentials (AP arose in the phloem after chilling; and (ii variation potentials (VP were evoked after wounding the leaf tip. Combined electric potential and gas exchange measurements showed that while the wound-induced VP moved rapidly towards the middle of the leaf to induce a reduction in both the net-CO2 uptake rate and the stomatal conductance, there was no response in the gas exchange to the cold-induced AP. To determine if electrical signalling had any impact on assimilate transport the middle of the leaf was exposed to 14CO2. Autoradiography of labelled assimilates provided evidence that phloem and intercellular transport of assimilates from mesophyll to bundle sheath cells was strongly reduced while the cold-induced AP moved through. In contrast, wound-induced VP did not inhibit assimilate translocation but did reduce the amount of the labelled assimilate in phloem and bundle sheath cells. Biochemical analysis revealed that callose content increased significantly in chilled leaves while starch increased in chilled but decreased in wounded leaves. The results led to the conclusion that different stimulation types incite characteristic phloem-transmitted electrical signals, each with a specific influence on gas exchange and assimilate transport.

  15. Evaluation of the effect of clinostat rotation on pollen germination and tube development as a tool for selection of plants in Space

    Science.gov (United States)

    De Micco, Veronica; Scala, Michele; Aronne, Giovanna

    2006-05-01

    The choice of species and cultivar on which rely to sustain Close Loop Environmental Systems is generally approached by analysing the behaviour of plants in presence of stress (sporophytic selection). In this paper, we investigated the possibility to conduct the selection among genotypes in Space through the male gametophytic selection. Thus, we studied the effect of simulated microgravity on pollen germination and tube development of both woody and herbaceous crop species: Prunus armeniaca (apricot), P. dulcis (almond), Malus domestica (apple) and Vicia faba (broad bean). Pollen collected from just bloomed flowers was assessed for viability and incubated on the optimal growing medium in petri dishes both on a uni-axial clinostat and stationary in 1g. Then, pollen was observed under a light microscope to detect percent germination and growth direction. Histochemical analyses were performed to verify the presence and distribution of storage substances. Moreover, specific stainings and epifluorescent microscopy were applied to count nuclei, follow the migration of sperm cells and investigate the presence, size and morphology of callose plugs. Results showed that simulated microgravity affected pollen tube development. The different response showed by the various species indicates that male-gametophytic selection could be useful for the selection of plants in microgravity.

  16. 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.

  17. 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.

  18. The wheat homolog of putative nucleotide-binding site-leucine-rich repeat resistance gene TaRGA contributes to resistance against powdery mildew.

    Science.gov (United States)

    Wang, Defu; Wang, Xiaobing; Mei, Yu; Dong, Hansong

    2016-03-01

    Powdery mildew, one of the most destructive wheat diseases worldwide, is caused by Blumeria graminis f. sp. tritici (Bgt), a fungal species with a consistently high mutation rate that makes individual resistance (R) genes ineffective. Therefore, effective resistance-related gene cloning is vital for breeding and studying the resistance mechanisms of the disease. In this study, a putative nucleotide-binding site-leucine-rich repeat (NBS-LRR) R gene (TaRGA) was cloned using a homology-based cloning strategy and analyzed for its effect on powdery mildew disease and wheat defense responses. Real-time reverse transcription-PCR (RT-PCR) analyses revealed that a Bgt isolate 15 and salicylic acid stimulation significantly induced TaRGA in the resistant variety. Furthermore, the silencing of TaRGA in powdery mildew-resistant plants increased susceptibility to Bgt15 and prompted conidia propagation at the infection site. However, the expression of TaRGA in leaf segments after single-cell transient expression assay highly increased the defense responses to Bgt15 by enhancing callose deposition and phenolic autofluorogen accumulation at the pathogen invading sites. Meanwhile, the expression of pathogenesis-related genes decreased in the TaRGA-silenced plants and increased in the TaRGA-transient-overexpressing leaf segments. These results implied that the TaRGA gene positively regulates the defense response to powdery mildew disease in wheat.

  19. Cytological and molecular analysis of nonhost resistance in rice to wheat powdery mildew and leaf rust pathogens.

    Science.gov (United States)

    Cheng, Yulin; Yao, Juanni; Zhang, Hongchang; Huang, Lili; Kang, Zhensheng

    2015-07-01

    Cereal powdery mildews caused by Blumeria graminis and cereal rusts caused by Puccinia spp. are constant disease threats that limit the production of almost all important cereal crops. Rice is an intensively grown agricultural cereal that is atypical because of its immunity to all powdery mildew and rust fungi. We analyzed the nonhost interactions between rice and the wheat powdery mildew fungus B. graminis f. sp. tritici (Bgt) and the wheat leaf rust fungus Puccinia triticina (Ptr) to identify the basis of nonhost resistance (NHR) in rice against cereal powdery mildew and rust fungi at cytological and molecular levels. No visible symptoms were observed on rice leaves inoculated with Bgt or Ptr. Microscopic observations showed that both pathogens exhibited aberrant differentiation and significantly reduced penetration frequencies on rice compared to wheat. The development of Bgt and Ptr was also completely arrested at early infection stages in cases of successful penetration into rice leaves. Attempted infection of rice by Bgt and Ptr induced similar defense responses, including callose deposition, accumulation of reactive oxygen species, and hypersensitive response in rice epidermal and mesophyll cells, respectively. Furthermore, a set of defense-related genes were upregulated in rice against Bgt and Ptr infection. Rice is an excellent monocot model for genetic and molecular studies. Therefore, our results demonstrate that rice is a useful model to study the mechanisms of NHR to cereal powdery mildew and rust fungi, which provides useful information for the development of novel and durable strategies to control these important pathogens.

  20. Pollen Grain Germination and Pollen Tube Growth in Pistil of Rice

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The germination of pollen grain in vitro and the growth of pollen tube in the pistil of rice were observed with a microscope.The stigma was removed at different time points after pollination to study its effect on seed setting rate.The rice pollen grain started to germinate at 2 min after pollination and the pollen tube penetrated stigma into style in 5-10 min,30 min later the end of pollen tube reached the bottom of ovary,and only some pollen tubes arrived at embryo sac at 40 min after pollination.Meanwhile,a small amount of catlose began to deposit in the pollen tubes,a great deal of callose was observed at 50 min after pollination,whereas the pollen grain began to shrink.The growing rates of pollen tube in the rice stigma,style and ovary were 1500,5000,and 5400 pm/h,respectively.The seed setting rate was quite low when the stigma was removed at about 10-15 min after pollination,gradually increased when it removed at 20 min to 50 min after pollination,and over 60%when it removed at 50 min after pollination and finally tended to be stable.

  1. 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.

  2. Gender Influence on White Matter Microstructure: A Tract-Based Spatial Statistics Analysis

    Science.gov (United States)

    Kanaan, Richard A.; Chaddock, Christopher; Allin, Matthew; Picchioni, Marco M.; Daly, Eileen; Shergill, Sukhi S.; McGuire, Philip K.

    2014-01-01

    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. PMID:24603769

  3. Impact of in utero exposure to EtOH on corpus callosum development and paw preference in rats: protective effects of silymarin

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    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.

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

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    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.

  5. Comprehensive transcriptional and functional analyses of melatonin synthesis genes in cassava reveal their novel role in hypersensitive-like cell death

    Science.gov (United States)

    Wei, Yunxie; Hu, Wei; Wang, Qiannan; Liu, Wei; Wu, Chunjie; Zeng, Hongqiu; Yan, Yu; Li, Xiaolin; He, Chaozu; Shi, Haitao

    2016-01-01

    Melatonin is a widely known hormone in animals. Since melatonin was discovered in plants, more and more studies highlight its involvement in a wide range of physiological processes including plant development and stress responses. Many advances have been made in the terms of melatonin-mediated abiotic stress resistance and innate immunity in plants, focusing on model plants such as rice and Arabidopsis. In this study, 7 melatonin synthesis genes were systematically analyzed in cassava. Quantitative real-time PCR showed that all these genes were commonly regulated by melatonin, flg22, Xanthomonas axonopodis pv manihotis (Xam) and hydrogen peroxide (H2O2). Transient expression in Nicotiana benthamiana revealed the subcellular locations and possible roles of these melatonin synthesis genes. Notably, we highlight novel roles of these genes in hypersensitive-like cell death, as confirmed by the results of several physiological parameters. Moreover, transient expression of these genes had significant effects on the transcripts of reactive oxygen species (ROS) accumulation and defense-related genes, and triggered the burst of callose depositions and papillae-associated plant defense, indicating the possible role of them in plant innate immunity. Taken together, this study reveals the comprehensive transcripts and putative roles of melatonin synthesis genes as well as melatonin in immune responses in cassava. PMID:27739451

  6. Social network diversity and white matter microstructural integrity in humans.

    Science.gov (United States)

    Molesworth, Tara; Sheu, Lei K; Cohen, Sheldon; Gianaros, Peter J; Verstynen, Timothy D

    2015-09-01

    Diverse aspects of physical, affective and cognitive health relate to social integration, reflecting engagement in social activities and identification with diverse roles within a social network. However, the mechanisms by which social integration interacts with the brain are unclear. In healthy adults (N = 155), we tested the links between social integration and measures of white matter microstructure using diffusion tensor imaging. Across the brain, there was a predominantly positive association between a measure of white matter integrity, fractional anisotropy (FA), and social network diversity. This association was particularly strong in a region near the anterior corpus callosum and driven by a negative association with the radial component of the diffusion signal. This callosal region contained projections between bilateral prefrontal cortices, as well as cingulum and corticostriatal pathways. FA within this region was weakly associated with circulating levels of the inflammatory cytokine interleukin-6 (IL-6), but IL-6 did not mediate the social network and FA relationship. Finally, variation in FA indirectly mediated the relationship between social network diversity and intrinsic functional connectivity of medial corticostriatal pathways. These findings suggest that social integration relates to myelin integrity in humans, which may help explain the diverse aspects of health affected by social networks.

  7. [A case of astrocytoma of corpus callosum presented diagnostic dyspraxia].

    Science.gov (United States)

    Koshimizu, K; Takeyama, E; Takeyama, E; Kizuki, H; Tei, H; Kubo, O

    1995-08-01

    A case of astrocytoma whose first clinical presentation was diagnostic dyspraxia was reported. A 38-year-old right-handed male experienced funny motion of his left hand triggered by voluntary movement of his right hand. One day, he tried to insert a coin into the vending machine with his right hand, then the left hand was against the other. One month after that event, he experienced headache and vertigo. On admission, there were no abnormal findings on neurological examination. On neuropsychological examination, he was cooperative, well orientated and attentive, and there were no callosal disconnection symptoms. Frontal lobe function tests were slightly impaired. T1-weighted MRI demonstrated irregular mixed signal intensity mass lesion extending from the genu to the body of the corpus callosum and the cingulate gyrus. This lesion was slightly enhanced with Gd-DTPA. Biopsy was performed and histological diagnosis was fibrillary astrocytoma. After irradiation and chemotherapy, he was discharged from the hospital without evident neurological deficit. About 20 cases of diagnostic dyspraxia have been reported and almost all of them were caused by cerebro-vascular disease. This is the first case of brain tumor who presented diagnostic dyspraxia.

  8. 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.

  9. 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

    2016-01-01

    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. PMID:27146059

  10. White matter microstructural characteristics in newly diagnosed Parkinson’s disease: An unbiased whole-brain study

    Science.gov (United States)

    Wen, Ming-Ching; Heng, Hannah S. E.; Ng, Samuel Y. E.; Tan, Louis C. S.; Chan, Ling Ling; Tan, Eng King

    2016-01-01

    Parkinson’s disease (PD) is a debilitating neurodegenerative disorder. Findings on specific white matter (WM) alterations in PD have been inconsistent. We hypothesized that WM changes occur in early PD patients and unbiased whole-brain analysis may provide additional evidence of pathological WM changes in PD. In this study, we examined various indexes of WM microstructure in newly diagnosed PD patients at the whole-brain level. 64 PDs with Hoehn & Yahr stage 1 (HY1PDs), 87 PDs with Hoehn & Yahr stage 2 (HYPD2s), and 60 controls (HCs) were recruited. Tract-based spatial statistics (TBSS) and diffusion connectometry were used to identify changes of WM pathways associated with PD. There were no significant differences in axial diffusivity, but HY1PDs exhibited greater fractional anisotropy (FA) and decreased mean and radial diffusivities (MD and RD) in callosal, projection, and association fibres than HCs and HY2PDs. Motor severity was inversely correlated with FA, but positively correlated with MD and RD in PD patients. Connectometry analysis also revealed increased WM density in the aforementioned tracts in PD patients, compared with HCs. Our study reveals WM enhancement, suggesting neural compensations in early PD. Longitudinal follow-up studies are warranted to identify the trajectory of WM changes alongside the progression of PD. PMID:27762307

  11. A pure case of Gerstmann syndrome with a subangular lesion.

    Science.gov (United States)

    Mayer, E; Martory, M D; Pegna, A J; Landis, T; Delavelle, J; Annoni, J M

    1999-06-01

    The four symptoms composing Gerstmann's syndrome were postulated to result from a common cognitive denominator (Grundstörung) by Gerstmann himself. He suggested that it is a disorder of the body schema restricted to the hand and fingers. The existence of a Grundstörung has since been contested. Here we suggest that a common psychoneurological factor does exist, but should be related to transformations of mental images rather than to the body schema. A patient (H.P.) was studied, who presented the four symptoms of Gerstmann's syndrome in the absence of any other neuropsychological disorders. MRI showed a focal ischaemic lesion, situated subcortically in the inferior part of the left angular gyrus and reaching the superior posterior region of T1. The cortical layers were spared and the lesion was seen to extend to the callosal fibres. On the basis of an extensive cognitive investigation, language, praxis, memory and intelligence disorders were excluded. The four remaining symptoms (finger agnosia, agraphia, right-left disorientation and dyscalculia) were investigated thoroughly with the aim of determining any characteristics that they might share. Detailed analyses of the tetrad showed that the impairment was consistently attributable to disorders of a spatial nature. Furthermore, cognitive tests necessitating mental rotation were equally shown to be impaired, confirming the essentially visuospatial origin of the disturbance. In the light of this report, the common cognitive denominator is hypothesized to be an impairment in mental manipulation of images and not in body schema.

  12. Alterações anatômicas em algodoeiro infectado pelo vírus da doença azul Anatomical alterations in blue disease infected cotton plant

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    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.

  13. 七叶树小孢子发生及雄配子体发育研究%Microsporogenesis and Male Gametogenesis in Aesculus chinensis Bunge

    Institute of Scientific and Technical Information of China (English)

    赵桦; 孟华菊; 徐娟

    2011-01-01

    用石蜡切片法观察了七叶树花药的发育过程.结果表明:(1)雄蕊花药四室,花药壁完全分化时,从外到内依次是表皮、药室内壁、中层和绒毡层,花药壁发育为基本型.表皮细胞1层,发育过程中始终存在;药室内壁在花药成熟时形成带状纤维层加厚;幼小花药壁的中层3~4层细胞,在花药发育成熟时退化消失;绒毡层1层细胞,发育类型为分泌型,小孢子母细胞减数分裂时绒毡层开始退化解体,花药成熟完全消失,仅剩1层绒毡层膜.每一花药中有多列雄性孢原细胞,发生于幼小花药表皮下方;(2)小孢子母细胞减数分裂为同时型,四分体多呈正四面体排列;减数分裂过程中,小孢子母细胞外方被胼胝质壁所包被,小孢子形成后胼胝质壁逐渐消失.成熟花粉二细胞型,外形呈圆三角状,具三孔沟.%The microsporogenesis and development of male gametophyte of Aesculus chinensis Bunge were observed by the method of paraffin sections. The main results as follows:The anther is 4 sporangiates and the development of anther wall is the basic type, which is composed of epidermis, endothecium, middle layer and tapetum. The epidermise consist of one layer of cells and still existed as the anther matured. The endothecium developed banding-shaped thickenings when the anther matured. The young anther wall has 3~4 layer middle layers and degenerated when maturity of the anther. The tapetum has dual origin and belong to secretory type, which degenerated just leavening the tapetal membrane at the time of anther matured.The archesporium derived from the cell under the epidermis. The cytokinesis of the microspore mother cells in meiosis is simultaneous. Most of the microspore tetrads are tetrahedral and lest of them are isobilateral.The walls of the microspore mother cells become thicker by the deposition of callose at the time of meiosis and the callose wall were degenerated at the time of microspores. Mature pollen

  14. Corpus callosum thickness in children: an MR pattern-recognition approach on the midsagittal image.

    Science.gov (United States)

    Andronikou, Savvas; Pillay, Tanyia; Gabuza, Lungile; Mahomed, Nasreen; Naidoo, Jaishree; Hlabangana, Linda Tebogo; du Plessis, Vicci; Prabhu, Sanjay P

    2015-02-01

    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.

  15. The effects of microgravity and clinorotation on the interaction of plant cells with fungal pathogen

    Science.gov (United States)

    Nedukha, O.; Kordyum, E.; Leach, J.; Martyn, G.; Ryba-White, M.

    The influence of microgravity and slow horizontal clinorotation (2 rev/min), which partly mimics microgravity, on the interaction of plant cells of soybean roots to Phytophthora sojae and of potato minitubers to Phytophthora infestans was studied during the Space Shuttle Mission STS-87 and during clinorotation. Seedlings of soybean cultivar Williams 82 grown in spaceflight and at 1 g were untreated or inoculated with pathogen P. sojae; minitubers of potato (cv Adreta) grown at horizontal clinorotation and the vertical control also were untreated or inoculated with pathogen P. infestans. The methods of light microscopy, scanning and transmission electron microscopy, confocal microscopy and also cytochemistry for the determination of callose content and peroxydase activity were used in the experiments. Post-landing analysis of the meristem cells of soybean roots infected with P. sojae and post-clinorotation analysis of the parenchyma cells of potato minitubers cells infected with P. infestans showed more destroying symptoms in cells of plant-host, which were more extensive colonized relative to the controls exposed to the pathogen fungus. Infected cells of plants-host were divided in two types: cells of first type were completely destroyed and hyphae of pathogen fungus were into these cells or in intercellular spaces; cells of second type characterized by partly changed ultrastructure and a calcium sites were contained above in mentioned cells. These data suggest that root cells of soybean seedlings grown in microgravity and cells of potato minitubers grown at slow horizontal clinorotation are more susceptible to penetration of a fungal pathogen in comparison with the corresponding controls.

  16. 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.

  17. 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

  18. Deciphering the responses of root border-like cells of Arabidopsis and flax to pathogen-derived elicitors.

    Science.gov (United States)

    Plancot, Barbara; Santaella, Catherine; Jaber, Rim; Kiefer-Meyer, Marie Christine; Follet-Gueye, Marie-Laure; Leprince, Jérôme; Gattin, Isabelle; Souc, Céline; Driouich, Azeddine; Vicré-Gibouin, Maïté

    2013-12-01

    Plant pathogens including fungi and bacteria cause many of the most serious crop diseases. The plant innate immune response is triggered upon recognition of microbe-associated molecular patterns (MAMPs) such as flagellin22 and peptidoglycan. To date, very little is known of MAMP-mediated responses in roots. Root border cells are cells that originate from root caps and are released individually into the rhizosphere. Root tips of Arabidopsis (Arabidopsis thaliana) and flax (Linum usitatissimum) release cells known as "border-like cells." Whereas root border cells of pea (Pisum sativum) are clearly involved in defense against fungal pathogens, the function of border-like cells remains to be established. In this study, we have investigated the responses of root border-like cells of Arabidopsis and flax to flagellin22 and peptidoglycan. We found that both MAMPs triggered a rapid oxidative burst in root border-like cells of both species. The production of reactive oxygen species was accompanied by modifications in the cell wall distribution of extensin epitopes. Extensins are hydroxyproline-rich glycoproteins that can be cross linked by hydrogen peroxide to enhance the mechanical strength of the cell wall. In addition, both MAMPs also caused deposition of callose, a well-known marker of MAMP-elicited defense. Furthermore, flagellin22 induced the overexpression of genes involved in the plant immune response in root border-like cells of Arabidopsis. Our findings demonstrate that root border-like cells of flax and Arabidopsis are able to perceive an elicitation and activate defense responses. We also show that cell wall extensin is involved in the innate immunity response of root border-like cells.

  19. Quarter and cow risk factors associated with a somatic cell count greater than 199,000 cells per milliliter in united Kingdom dairy cows

    Science.gov (United States)

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

    2009-01-01

    Quarter and cow risk factors associated with a somatic cell count (SCC) >199,000 cells/mL at the next milk recording during lactation were investigated during a 12-mo longitudinal study on 8 commercial Holstein-Friesian dairy herds in Southwest England, United Kingdom. The individual risk factors studied on 1,677 cows included assessments of udder and leg hygiene, teat-end callosity and hyperkeratosis, body condition score (BCS), and measurements of monthly milk quality and yield. The outcome variable used for statistical analysis was the next recorded individual cow SCC >199,000 cells/mL. Statistical analysis included use of generalized linear mixed models. Significant covariates associated with an increased risk of SCC >199,000 cells/mL were increasing parity, increasing month of lactation, previous SCC (SCC 200,000 cells/mL and greater, odds ratio = 7.12), and cows with a BCS BCS >3.5 (odds ratio = 2.20). Significant covariates associated with a reduced risk of SCC >199,000 cells/mL were cows with contamination of the skin of the udder and quarters with mild (odds ratio = 0.65) and moderate (odds ratio = 0.62) hyperkeratosis of the teat-end. These results suggest that individual quarter and cow-level factors are important in the acquisition of intramammary infections as measured by SCC during lactation. Cow energy status, as measured by BCS, may influence the risk of intramammary infection during lactation. PMID:19528588

  20. 玫瑰与月季种间杂交障碍原因分析%Analysis on the Barriers of Interspecific Hybridization BetweenRosa rugosa andRosa hybrid

    Institute of Scientific and Technical Information of China (English)

    于晓艳; 邢树堂; 赵兰勇

    2014-01-01

    [Objective] The aim of this study is to reveal the reasons for barriers of interspecific hybridization betweenR. rugosa andR. hybrid. It is meaningful to improve the theory and techniques of breeding ornamentalR. rugosa.[Method] A wildR. rugosa from Muping, a cultivar ofR. rugosa ‘Tanghong’ , two cultivars ofR. hybrid ‘Salvia’ and ‘Red Cap’ were used as plant materials. The fruit setting rate, seed number per fruit, seed length, percentage of seeds with embryo, germination rate of seeds with embryo and survived seedling rate of interspecific hybridization (MPבSalvia’, MPבRed Cap’) and intervarietal hybridization (MPבTanghong’) were investigated. The growth of pollen tubes in the styles was observed with fluorescent microscope, Fertilization and development of embryos were observed by conventional paraffin sectioning.[Result] The fruit setting rate and seed number per fruit of MPבSalvia’ were significantly lower than those of intervarietal hybridization. No seed was obtained from MP בRed Cap’. The seeds of MPבSalvia’ were of uneven size. The length of 76.67% of small seeds with no embryo and endosperm was simply (0.24±0.07) cm, these small seeds could not germinate. The length of 23.33% of big seeds with embryo and endosperm was (0.61±0.05) cm. But the germination rate and survived seedling rate of these big seeds were significantly lower than those of intervarietal hybridization. Two hours after pollination, the pollens of interspecific hybridization and intervarietal hybridization both germinated on the chapiters, but a great deal of callose deposited at the apex of pollen tubes of interspecific hybridization. Twenty to twenty-four hours after pollination, pollen tubes of intervarietal hybridization grew into ovary, but all the pollen tubes of MPבRed Cap’ and most of the pollen tubes of MPבSalvia’ were arrested at the middle of the styles. Little callose accumulated in the canal cells and spaces of the

  1. The synthetic cationic lipid diC14 activates a sector of the Arabidopsis defence network requiring endogenous signalling components.

    Science.gov (United States)

    Cambiagno, Damián Alejandro; Lonez, Caroline; Ruysschaert, Jean-Marie; Alvarez, María Elena

    2015-12-01

    Natural and synthetic elicitors have contributed significantly to the study of plant immunity. Pathogen-derived proteins and carbohydrates that bind to immune receptors, allow the fine dissection of certain defence pathways. Lipids of a different nature that act as defence elicitors, have also been studied, but their specific effects have been less well characterized, and their receptors have not been identified. In animal cells, nanoliposomes of the synthetic cationic lipid 3-tetradecylamino-tert-butyl-N-tetradecylpropionamidine (diC14) activate the TLR4-dependent immune cascade. Here, we have investigated whether this lipid induces Arabidopsis defence responses. At the local level, diC14 activated early and late defence gene markers (FRK1, WRKY29, ICS1 and PR1), acting in a dose-dependent manner. This lipid induced the salicylic acid (SA)-dependent, but not jasmonic acid (JA)-dependent, pathway and protected plants against Pseudomonas syringae pv. tomato (Pst), but not Botrytis cinerea. diC14 was not toxic to plant or pathogen, and potentiated pathogen-induced callose deposition. At the systemic level, diC14 induced PR1 expression and conferred resistance against Pst. diC14-induced defence responses required the signalling protein EDS1, but not NDR1. Curiously, the lipid-induced defence gene expression was lower in the fls2/efr/cerk1 triple mutant, but still unchanged in the single mutants. The amidine headgroup and chain length were important for its activity. Given the robustness of the responses triggered by diC14, its specific action on a defence pathway and the requirement for well-known defence components, this synthetic lipid is emerging as a useful tool to investigate the initial events involved in plant innate immunity.

  2. Diagonistic dyspraxia. Clinical characteristics, responsible lesion and possible underlying mechanism.

    Science.gov (United States)

    Tanaka, Y; Yoshida, A; Kawahata, N; Hashimoto, R; Obayashi, T

    1996-06-01

    We present three patients who showed, in addition to signs of callosal interruption, a variety of abnormal motor behaviour of the left hand dissociated from conscious volition, in the absence of pathological grasping phenomena. The abnormal movements of the left hand consisted of (i) antagonistic movements to the right; (ii) non-antagonistic, irrelevant movements to the right; (iii) symmetric movements to the right in which the left hand sometimes preceded the right, and (iv) occasional inability to move at will during a bimanual task. From these observations and a review of previous publications, we propose that, in most right-handed subjects; diagonistic dyspraxia could be defined as abnormal motor behaviour of the left hand activated by voluntary movements of the right hand. Motor phenomena similar to diagonistic dyspraxia but attributable to impulsive groping movements induced by medial frontal lobe pathology should be excluded from diagonistic dyspraxia. Comparison of MRIs of the three patients with those of five patients who developed no diagonistic dyspraxia following an infarction of the corpus callosum, with or without medial hemispheric involvement, revealed that damage to the ventral part of the posterior end of the body of the corpus callosum was crucial for the development of diagonistic dyspraxia. Since the commissural fibres between the superior parietal lobules pass through the caudal part of the body of the corpus callosum, and also since there is accumulating evidence that the human superior parietal lobule is concerned with selection of movement based on the integration of visual and/or somatosensory information, we infer that diagonistic dyspraxia is produced by a disconnection of the right superior parietal lobule from the left which is dominant for volitional control of movement in most right-handed subjects.

  3. Acupuncture inhibits cue-induced heroin craving and brain activation

    Institute of Scientific and Technical Information of China (English)

    Xinghui Cai; Xiaoge Song; Chuanfu Li; Chunsheng Xu; Xiliang Li; Qi Lu

    2012-01-01

    Previous research using functional MRI has shown that specific brain regions associated with drug dependence and cue-elicited heroin craving are activated by environmental cues.Craving is an important trigger of heroin relapse,and acupuncture may inhibit craving.In this study,we performed functional MRI in heroin addicts and control subjects.We compared differences in brain activation between the two groups during heroin cue exposure,heroin cue exposure plus acupuncture at the Zusanli point(ST36)without twirling of the needle,and heroin cue exposure plus acupuncture at the Zusanli point with twirling of the needle.Heroin cue exposure elicited significant activation in craving-related brain regions mainly in the frontal lobes and callosal gyri.Acupuncture without twirling did not significantly affect the range of brain activation induced by heroin cue exposure,but significantly changed the extent of the activation in the heroin addicts group.Acupuncture at the Zusanli.point with twirling of the needle significantly decreased both the range and extent of activation induced by heroin cue exposure compared with heroin cue exposure plus acupuncture without twirling of the needle.These experimental findings indicate that presentation of heroin cues can induce activation in craving-related brain regions,which are involved in reward,learning and memory,cognition and emotion.Acupuncture at the Zusanli point can rapidly suppress the activation of specific brain regions related to craving,supporting its potential as an intervention for drug craving.

  4. Progress in Stroke Warning Syndrome%卒中预警综合征研究进展

    Institute of Scientific and Technical Information of China (English)

    曲长海; 王广田(综述); 曲方(审校)

    2015-01-01

    Stroke warning syndrome (SWS) is the particular type of stroke characterized by stereotyped, crescendo,recurrent,and short-lasting episodes of transient focal neurological deficits and is associated with a high risk of imminent lacunar infarction.On the basis of clinical and neuroimaging findings,it can be capsu-lar,pontine,or callosal warning syndrome.The pathophysiology of SWS is complex,and may involve lipohyali-nosis or microatheromatosis and hemodynamic mechanisms of small cerebral vessels ,as well as the peri-infarct depolarizations affecting adjacent motor pathways .Different treatment modalities for SWS have been pro-posed,but no conclusive data.%卒中预警综合征( SWS)是一种特殊类型的卒中,特点是刻板、渐强、反复发作的局灶性神经功能缺损,并与即将发生腔隙性脑梗死的高风险有关。根据临床表现和神经影像学所见,可分为内囊、脑桥或胼胝体预警综合征。 SWS的病理生理机制复杂,可能涉及脑小血管透明样变性或微动脉粥样硬化、血流动力学机制以及梗死周边去极化影响相邻运动感觉通路等。目前已经提出的多种治疗方法,尚缺少确凿的数据。该文就SWS的研究进展予以综述。

  5. Non-host defense response in a novel Arabidopsis-Xanthomonas citri subsp. citri pathosystem.

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    Chuanfu An

    Full Text Available Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc, is one of the most destructive diseases of citrus. Progress of breeding citrus canker-resistant varieties is modest due to limited resistant germplasm resources and lack of candidate genes for genetic manipulation. The objective of this study is to establish a novel heterologous pathosystem between Xcc and the well-established model plant Arabidopsis thaliana for defense mechanism dissection and resistance gene identification. Our results indicate that Xcc bacteria neither grow nor decline in Arabidopsis, but induce multiple defense responses including callose deposition, reactive oxygen species and salicylic aicd (SA production, and defense gene expression, indicating that Xcc activates non-host resistance in Arabidopsis. Moreover, Xcc-induced defense gene expression is suppressed or attenuated in several well-characterized SA signaling mutants including eds1, pad4, eds5, sid2, and npr1. Interestingly, resistance to Xcc is compromised only in eds1, pad4, and eds5, but not in sid2 and npr1. However, combining sid2 and npr1 in the sid2npr1 double mutant compromises resistance to Xcc, suggesting genetic interactions likely exist between SID2 and NPR1 in the non-host resistance against Xcc in Arabidopsis. These results demonstrate that the SA signaling pathway plays a critical role in regulating non-host defense against Xcc in Arabidopsis and suggest that the SA signaling pathway genes may hold great potential for breeding citrus canker-resistant varieties through modern gene transfer technology.

  6. Plantacyanin plays a role in reproduction in Arabidopsis.

    Science.gov (United States)

    Dong, Juan; Kim, Sun Tae; Lord, Elizabeth M

    2005-06-01

    Plantacyanins belong to the phytocyanin family of blue copper proteins. In the Arabidopsis (Arabidopsis thaliana) genome, only one gene encodes plantacyanin. The T-DNA-tagged mutant is a knockdown mutant that shows no visible phenotype. We used both promoter-beta-glucuronidase transgenic plants and immunolocalization to show that Arabidopsis plantacyanin is expressed most highly in the inflorescence and, specifically, in the transmitting tract of the pistil. Protein levels show a steep gradient in expression from the stigma into the style and ovary. Overexpression plants were generated using cauliflower mosaic virus 35S, and protein levels in the pistil were examined as well as the pollination process. Seed set in these plants is highly reduced mainly due to a lack of anther dehiscence, which is caused by degeneration of the endothecium. Callose deposits occur on the pollen walls in plants that overexpress plantacyanin, and a small percentage of these pollen grains germinate in the closed anthers. When wild-type pollen was used on the overexpression stigma, seed set was still decreased compared to the control pollinations. We detected an increase in plantacyanin levels in the overexpression pistil, including the transmitting tract. Guidance of the wild-type pollen tube on the overexpression stigma is disrupted as evidenced by the growth behavior of pollen tubes after they penetrate the papillar cell. Normally, pollen tubes travel down the papilla cell and into the style. Wild-type pollen tubes on the overexpression stigma made numerous turns around the papilla cell before growing toward the style. In some rare cases, pollen tubes circled up the papilla cell away from the style and were arrested there. We propose that when plantacyanin levels in the stigma are increased, pollen tube guidance into the style is disrupted.

  7. 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.

  8. Structural integrity of the corpus callosum predicts long-term transfer of fluid intelligence-related training gains in normal aging.

    Science.gov (United States)

    Wolf, Dominik; Fischer, Florian Udo; Fesenbeckh, Johanna; Yakushev, Igor; Lelieveld, Irene Maria; Scheurich, Armin; Schermuly, Ingrid; Zschutschke, Lisa; Fellgiebel, Andreas

    2014-01-01

    Although cognitive training usually improves cognitive test performance, the capability to transfer these training gains into respective or functionally related cognitive domains varies significantly. Since most studies demonstrate rather limited transfer effects in older adults, aging might be an important factor in transfer capability differences. This study investigated the transfer capability of logical reasoning training gains to a measure of Fluid Intelligence (Gf) in relation to age, general intelligence, and brain structural integrity as measured by diffusion tensor imaging. In a group of 41 highly educated healthy elderly, 71% demonstrated successful transfer immediately after a 4-week training session (i.e. short-term transfer). In a subgroup of 22% of subjects transfer maintained over a 3-month follow-up period (i.e. long-term transfer). While short-term transfer was not related to structural integrity, long-term transfer was associated with increased structural integrity in corpus and genu of the corpus callosum. Since callosal structural integrity was also related to age (in the present and foregoing studies), previously observed associations between age and transfer might be moderated by the structural integrity. Surprisingly, age was not directly associated with transfer in this study which could be explained by the multi-dependency of the structural integrity (modulating factors beside age, e.g. genetics). In this highly educated sample, general intelligence was not related to transfer suggesting that high intelligence is not sufficient for transfer in normal aging. Further studies are needed to reveal the interaction of transfer, age, and structural integrity and delineate mechanisms of age-dependent transfer capabilities.

  9. 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.

  10. Sex differences in white matter integrity in youths with attention-deficit/hyperactivity disorder: a pilot study

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    Jace Bradford King

    2015-07-01

    Full Text Available 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 preform 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

  11. Optimal Route for Mesenchymal Stem Cells Transplantation after Severe Intraventricular Hemorrhage in Newborn Rats.

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    So Yoon Ahn

    Full Text Available Recently, we showed that intracerebroventricular (IC transplantation of human umbilical cord blood (UCB-derived mesenchymal stem cells (MSCs significantly attenuates posthemorrhagic hydrocephalus (PHH and brain damage after severe IVH in newborn rats. This study was performed to determine the optimal route for transplanting MSCs for severe IVH by comparing IC transplantation, intravenous (IV transplantation, and IV transplantation plus mannitol infusion. Severe IVH was induced by injecting 100 uL of blood into each ventricle of Sprague-Dawley rats on postnatal day 4 (P4. After confirming severe IVH with brain magnetic resonance imaging (MRI at P5, human UCB-derived MSCs were transplanted at P6 by an IC route (1×105, an IV route (5×105, or an IV route with mannitol infused. Follow-up brain MRIs and rotarod tests were performed. At P32, brain tissue samples were obtained for biochemical and histological analyses. Although more MSCs localized to the brain after IC than after IV delivery, both methods were equally effective in preventing PHH; attenuating impaired rotarod test; increasing the number of TUNEL-positive cells, inflammatory cytokines, and astrogliosis; and reducing corpus callosal thickness and myelin basic protein expression after severe IVH regardless of mannitol co-infusion. Despite the superior delivery efficacy with IC than with the IV route, both IC and IV transplantation of MSCs had equal therapeutic efficacy in protecting against severe IVH. These findings suggest that the less invasive IV route might be a good alternative for clinically unstable, very preterm infants that cannot tolerate a more invasive IC delivery of MSCs.

  12. Segmentation and Analysis of Corpus Callosum in Alzheimer MR Images using Total Variation Based Diffusion Filter and Level Set Method.

    Science.gov (United States)

    Anandh, K R; Sujatha, C M; Ramakrishnan, S

    2015-01-01

    Alzheimer’s Disease (AD) is a common form of dementia that affects gray and white matter structures of brain. Manifestation of AD leads to cognitive deficits such as memory impairment problems, ability to think and difficulties in performing day to day activities. Although the etiology of this disease is unclear, imaging biomarkers are highly useful in the early diagnosis of AD. Magnetic resonance imaging is an indispensible non-invasive imaging modality that reflects both the geometry and pathology of the brain. Corpus Callosum (CC) is the largest white matter structure as well as the main inter-hemispheric fiber connection that undergoes regional alterations due to AD. Therefore, segmentation and feature extraction are predominantly essential to characterize the CC atrophy. In this work, an attempt has been made to segment CC using edge based level set method. Prior to segmentation, the images are pre-processed using Total Variation (TV) based diffusion filtering to enhance the edge information. Shape based geometric features are extracted from the segmented CC images to analyze the CC atrophy. Results show that the edge based level set method is able to segment CC in both the normal and AD images. TV based diffusion filtering has performed uniform region specific smoothing thereby preserving the texture and small scale details of the image. Consequently, the edge map of CC in both the normal and AD are apparently sharp and distinct with continuous boundaries. This facilitates the final contour to correctly segment CC from the nearby structures. The extracted geometric features such as area, perimeter and minor axis are found to have the percentage difference of 5.97%, 22.22% and 9.52% respectively in the demarcation of AD subjects. As callosal atrophy is significant in the diagnosis of AD, this study seems to be clinically useful.

  13. Spatial and temporal profiles of growth factor expression during CNS demyelination reveal the dynamics of repair priming.

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    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

  14. Both projection and commissural pathways are disrupted in individuals with chronic stroke: investigating microstructural white matter correlates of motor recovery

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    Borich Michael R

    2012-08-01

    Full Text Available Abstract Background 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. Results 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. Conclusions 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

  15. Redefining the phenotype of ALSP and AARS2 mutation–related leukodystrophy

    Science.gov (United States)

    Lakshmanan, Rahul; Adams, Matthew E.; Lynch, David S.; Kinsella, Justin A.; Phadke, Rahul; Schott, Jonathan M.; Murphy, Elaine; Rohrer, Jonathan D.; Chataway, Jeremy; Houlden, Henry; Fox, Nick C.

    2017-01-01

    Objective: To provide an overview of the phenotype of 2 clinically, radiologically, and pathologically similar leukodystrophies, adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) and alanyl-transfer RNA synthetase 2 mutation–related leukodystrophy (AARS2-L), and highlight key differentiating features. Methods: ALSP and AARS2-L cases were identified from the adult-onset leukodystrophy database at our institution. In addition, cases with imaging findings were identified from a literature review. The phenotypic features were determined by combining published cases with those from our database. Results: A combined total of 74 cases of ALSP and 10 cases of AARS2-L with neuroimaging data were identified. The mean age at onset was 42 years in ALSP and 26 years in AARS2-L. Cognitive and motor symptoms were the most common symptoms overall in both. Ovarian failure was exclusive to AARS2-L, present in all known female cases. Both ALSP and AARS2-L showed a confluent, asymmetric, predominantly frontoparietal, periventricular pattern of white matter disease with subcortical U-fiber sparing; pyramidal tract and corpus callosum involvement; and diffusion changes in the white matter which we have termed “deep white matter diffusion dots.” Central atrophy and corpus callosal thinning were prominent in ALSP and disproportionately mild in AARS2-L when present. ALSP also occasionally showed ventricular abnormalities and calcifications in the frontal periventricular white matter, features not seen in AARS2-L. AARS2-L demonstrates white matter rarefaction which suppresses on fluid-attenuated inversion recovery MRI sequences, a feature not seen in ALSP. Conclusions: ALSP and AARS2-L share similar clinical, imaging, and pathologic characteristics with key differentiating features that we have highlighted. PMID:28243630

  16. Adaptive algorithms to map how brain trauma affects anatomical connectivity in children

    Science.gov (United States)

    Dennis, Emily L.; Prasad, Gautam; Babikian, Talin; Kernan, Claudia; Mink, Richard; Babbitt, Christopher; Johnson, Jeffrey; Giza, Christopher C.; Asarnow, Robert F.; Thompson, Paul M.

    2015-12-01

    Deficits in white matter (WM) integrity occur following traumatic brain injury (TBI), and often persist long after the visible scars have healed. Heterogeneity in injury types and locations can complicate analyses, making it harder to discover common biomarkers for tracking recovery. Here we apply a newly developed adaptive connectivity method, EPIC (evolving partitions to improve connectomics) to identify differences in structural connectivity that persist longitudinally. This data comes from a longitudinal study, in which we scanned participants (aged 8-19 years) with anatomical and diffusion MRI in both the post-acute and chronic phases (1-6 months and 13-19 months post-injury). To identify patterns of abnormal connectivity, we trained a model on data from 32 TBI patients in the post-acute phase and 45 well-matched healthy controls, reducing an initial 68x68 connectivity matrix to a 14x14 matrix. We then applied this reduced parcellation to the chronic data in participants who had returned for their chronic assessment (21 TBI and 26 healthy controls) and tested for group differences. We found significant differences in two connections, comprising callosal fibers and long anterior-posterior fibers, with the TBI group showing increased fiber density relative to controls. Longitudinal analysis revealed that these were connections that were decreasing over time in the healthy controls, as is a common developmental phenomenon, but they were increasing in the TBI group. While we cannot definitively tell why this may occur with our current data, this study provides targets for longitudinal tracking, and poses questions for future investigation.

  17. Aging potentiates the acute and chronic neurological symptoms of pyrithiamine-induced thiamine deficiency in the rodent.

    Science.gov (United States)

    Pitkin, S R; Savage, L M

    2001-03-15

    The present study aimed to assess the role of advanced age in the development and manifestation of thiamine deficiency using an animal model of Wernicke-Korsakoff syndrome (WKS). Interactions between pyrithiamine-induced thiamine deficiency (PTD) and age were examined relative to working memory impairment and neuropathology in Fischer 344 rats. Young (2-3 months) and aged (22-23 months) F344 rats were assigned to one of two treatment conditions: PTD or pair-fed control (PF). Rats in the former group were further divided into three groups according to duration of PTD treatment. Working memory was assessed with an operant matching-to-position (MTP) task; after testing, animals were sacrificed and both gross and immunocytochemical measures of brain pathology were obtained. Aged rats exhibited acute neurological disturbances during the PTD treatment regime earlier than did young rats, and also developed more extensive neuropathology with a shorter duration of PTD. Aged rats displayed increased brain shrinkage (smaller frontal cortical and callosal thickness) as well as enhanced astrocytic activity in the thalamus and a decrease in ChAT-positive cell numbers in the medial septum; the latter two measures of neuropathology were potentiated by PTD. In both young and aged rats, and to a greater degree in the latter group, PTD reduced thalamic volume. Behaviorally, aged rats displayed impaired choice accuracy on the delayed MTP task. Regardless of age, rats with lesions centered on the internal medullary lamina of the thalamus also displayed impaired choice accuracy. Moreover, increased PTD treatment duration led to increased response times on the delayed MTP task. These results suggest that aging does indeed potentiate the neuropathology associated with experimental thiamine deficiency, supporting an age coupling hypothesis of alcohol-related neurological disorders.

  18. Nitric oxide, induced by wounding, mediates redox regulation in pelargonium leaves.

    Science.gov (United States)

    Arasimowicz, M; Floryszak-Wieczorek, J; Milczarek, G; Jelonek, T

    2009-09-01

    The subject of this study was the participation of nitric oxide (NO) in plant responses to wounding, promoted by nicking of pelargonium (Pelargonium peltatum L.) leaves. Bio-imaging with the fluorochrome 4,5-diaminofluorescein diacetate (DAF-2DA) and electrochemical in situ measurement of NO showed early (within minutes) and transient (2 h) NO generation after wounding restricted to the site of injury. In order to clarify the functional role of NO in relation to modulation of the redox balance during wounding, a pharmacological approach was used. A positive correlation was found between NO generation and regulation of the redox state. NO caused a slight restriction of post-wounded O(2) (-) production, in contrast to the periodic and marked increase in H(2)O(2) level. The observed changes were accompanied by time-dependent inhibition of catalase (CAT) and ascorbate peroxidase (APX) activity. The effect was specific to NO, since the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5 tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) reversed the inhibition of CAT and APX, as well as temporarily enhancing H(2)O(2) synthesis. Finally, cooperation of NO/H(2)O(2) restricted the depletion of the low-molecular weight antioxidant pool (i.e. ascorbic acid and thiols) was positively correlated with sealing and reconstruction changes in injured pelargonium leaves (i.e. lignin formation and callose deposition). The above results clearly suggest that NO may promote restoration of wounded tissue through stabilisation of the cell redox state and stimulation of the wound scarring processes.

  19. Microsurgical anatomy of the anterior cerebral artery in Indian cadavers

    Directory of Open Access Journals (Sweden)

    Shweta Kedia

    2013-01-01

    Full Text Available Background: The microanatomy features of cerebral arteries may be variable and may be different in different ethnic groups. Aim: To study the anterior cerebral artery (ACA anatomy in North-West Indian cadavers. Materials and Methods: Microanatomy features of the ACA were studied in 15 formalin fixed human cadaveric brains under microscope. The outer diameter, length, and number of perforating branches with respective anomalies were measured for each of the following vessels: ACA (proximal A1 segment to distal A2 segment, anterior communicating artery (ACoA, Recurrent artery of Heubner (RAH, and callosomarginal artery and photographed for documentation. Results: The mean length and external diameter of right and left A1 segment was 12.09 mm and 12.0 mm and 2.32 mm and 2.36 mm respectively. Narrowing, duplication, and median ACA were seen in 6.6%, 3.3% and 6.6% of the vessels respectively. Complex ACoA type was seen in 40% cadavers. RAH originated at an average point of 0.2 mm distal to ACoA, but in one cadaver it arose 5 mm proximal to ACoA. Double RAH was found in 26.6%. The course of RAH in relation to A1 was superiorly in 60%, in anteriorly 30% and posteriorly in 10% of cadavers. The orbitofrontal artery (OFA and frontopolar artery (FPA arose from A2 in 83.3% to 40% respectively. The mean distance of OFA and FPA from ACoA was 4.17 mm and 8.5 mm respectively. After giving rise to central, callosal and cortical branches, pericallosal artery terminated near the splenium of the corpus callosum or on the precuneus as the inferomedial parietal artery. Conclusion: Knowledge of the microvascular anatomy is indispensable and it is mandatory to be aware of the possible variations in the anomalies to minimize morbidity.

  20. Abnormal white matter properties in adolescent girls with anorexia nervosa

    Science.gov (United States)

    Travis, Katherine E.; Golden, Neville H.; Feldman, Heidi M.; Solomon, Murray; Nguyen, Jenny; Mezer, Aviv; Yeatman, Jason D.; Dougherty, Robert F.

    2015-01-01

    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. PMID:26740918

  1. Combination joint-preserving surgery for forefoot deformity in patients with rheumatoid arthritis.

    Science.gov (United States)

    Niki, H; Hirano, T; Okada, H; Beppu, M

    2010-03-01

    Proximal osteotomies for forefoot deformity in patients with rheumatoid arthritis have hitherto not been described. We evaluated combination joint-preserving surgery involving three different proximal osteotomies for such deformities. A total of 30 patients (39 feet) with a mean age of 55.6 years (45 to 67) underwent combined first tarsometatarsal fusion and distal realignment, shortening oblique osteotomies of the bases of the second to fourth metatarsals and a fifth-ray osteotomy. The mean follow-up was 36 months (24 to 68). The mean foot function index scores for pain, disability and activity subscales were 18, 23, and 16 respectively. The mean Japanese Society for Surgery of the Foot score improved significantly from 52.2 (41 to 68) to 89.6 (78 to 97). Post-operatively, 14 patients had forefoot stiffness, but had no disability. Most patients reported highly satisfactory walking ability. Residual deformity and callosities were absent. The mean hallux valgus and intermetatarsal angles decreased from 47.0 degrees (20 degrees to 67 degrees) to 9.0 degrees (2 degrees to 23 degrees) and from 14.1 degrees (9 degrees to 20 degrees) to 4.6 degrees (1 degree to 10 degrees), respectively. Four patients had further surgery including removal of hardware in three and a fifth-ray osteotomy in one. With good peri-operative medical management of rheumatoid arthritis, surgical repositioning of the metatarsophalangeal joint by metatarsal shortening and consequent relaxing of surrounding soft tissues can be successful. In early to intermediate stages of the disease, it can be performed in preference to joint-sacrificing procedures.

  2. Burkholderia phytofirmans PsJN confers grapevine resistance against Botrytis cinerea via a direct antimicrobial effect combined with a better resource mobilization

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    Lidiane Miotto-Vilanova

    2016-08-01

    Full Text Available Plant innate immunity serves as a surveillance system by providing the first line of powerful weapons to fight against pathogen attacks. Beneficial microorganisms and Microbial-Associated Molecular Patterns might act as signals to trigger this immunity. Burkholderia phytofirmans PsJN, a highly efficient plant beneficial endophytic bacterium, promotes growth in a wide variety of plants including grapevine. Further, the bacterium induces plant resistance against abiotic and biotic stresses. However, no study has deciphered triggered-mechanisms during the tripartite interaction between grapevine, B. phytofirmans PsJN and Botrytis cinerea. Herein, we showed that in contrast with classical rhizobacteria, which are restricted in the root system and act through ISR, B. phytofirmans PsJN is able to migrate until aerial part and forms at leaves surface a biofilm around B. cinerea mycelium to restrict the pathogen. Nevertheless, considering the endophytic level of PsJN in leaves, the plant protection efficacy of B. phytofirmans PsJN could not be explained solely by its direct antifungal effect. Deeper investigations showed a callose deposition, H2O2 production and primed expression of PR1, PR2, PR5 and JAZ only in bacterized-plantlets after pathogen challenge. The presence of PsJN modulated changes in leaf carbohydrate metabolism including gene expression, sugar levels and chlorophyll fluorescence imaging after Botrytis challenge. Our findings indicated that protection induced by B. phytofirmans PsJN was multifaceted and relied on a direct antifungal effect, priming of defense mechanisms as well as the mobilization of carbon sources in grapevine leaf tissues.

  3. Development of human white matter fiber pathways: From newborn to adult ages.

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    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.

  4. 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.

  5. Abnormal white matter properties in adolescent girls with anorexia nervosa

    Directory of Open Access Journals (Sweden)

    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.

  6. Corpus callosum thickness in children: an MR pattern-recognition approach on the midsagittal image

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    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.)

  7. c-Fos expression during temporal order judgment in mice.

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    Makoto Wada

    Full Text Available The neuronal mechanisms for ordering sensory signals in time still need to be clarified despite a long history of research. To address this issue, we recently developed a behavioral task of temporal order judgment in mice. In the present study, we examined the expression of c-Fos, a marker of neural activation, in mice just after they carried out the temporal order judgment task. The expression of c-Fos was examined in C57BL/6N mice (male, n = 5 that were trained to judge the order of two air-puff stimuli delivered bilaterally to the right and left whiskers with stimulation intervals of 50-750 ms. The mice were rewarded with a food pellet when they responded by orienting their head toward the first stimulus (n = 2 or toward the second stimulus (n = 3 after a visual "go" signal. c-Fos-stained cell densities of these mice (test group were compared with those of two control groups in coronal brain sections prepared at bregma -2, -1, 0, +1, and +2 mm by applying statistical parametric mapping to the c-Fos immuno-stained sections. The expression of c-Fos was significantly higher in the test group than in the other groups in the bilateral barrel fields of the primary somatosensory cortex, the left secondary somatosensory cortex, the dorsal part of the right secondary auditory cortex. Laminar analyses in the primary somatosensory cortex revealed that c-Fos expression in the test group was most evident in layers II and III, where callosal fibers project. The results suggest that temporal order judgment involves processing bilateral somatosensory signals through the supragranular layers of the primary sensory cortex and in the multimodal sensory areas, including marginal zone between the primary somatosensory cortex and the secondary sensory cortex.

  8. Identification and individualized prediction of clinical phenotypes in bipolar disorders using neurocognitive data, neuroimaging scans and machine learning.

    Science.gov (United States)

    Wu, Mon-Ju; Mwangi, Benson; Bauer, Isabelle E; Passos, Ives C; Sanches, Marsal; Zunta-Soares, Giovana B; Meyer, Thomas D; Hasan, Khader M; Soares, Jair C

    2017-01-15

    Diagnosis, clinical management and research of psychiatric disorders remain subjective - largely guided by historically developed categories which may not effectively capture underlying pathophysiological mechanisms of dysfunction. Here, we report a novel approach of identifying and validating distinct and biologically meaningful clinical phenotypes of bipolar disorders using both unsupervised and supervised machine learning techniques. First, neurocognitive data were analyzed using an unsupervised machine learning approach and two distinct clinical phenotypes identified namely; phenotype I and phenotype II. Second, diffusion weighted imaging scans were pre-processed using the tract-based spatial statistics (TBSS) method and 'skeletonized' white matter fractional anisotropy (FA) and mean diffusivity (MD) maps extracted. The 'skeletonized' white matter FA and MD maps were entered into the Elastic Net machine learning algorithm to distinguish individual subjects' phenotypic labels (e.g. phenotype I vs. phenotype II). This calculation was performed to ascertain whether the identified clinical phenotypes were biologically distinct. Original neurocognitive measurements distinguished individual subjects' phenotypic labels with 94% accuracy (sensitivity=92%, specificity=97%). TBSS derived FA and MD measurements predicted individual subjects' phenotypic labels with 76% and 65% accuracy respectively. In addition, individual subjects belonging to phenotypes I and II were distinguished from healthy controls with 57% and 92% accuracy respectively. Neurocognitive task variables identified as most relevant in distinguishing phenotypic labels included; Affective Go/No-Go (AGN), Cambridge Gambling Task (CGT) coupled with inferior fronto-occipital fasciculus and callosal white matter pathways. These results suggest that there may exist two biologically distinct clinical phenotypes in bipolar disorders which can be identified from healthy controls with high accuracy and at an

  9. Disrupted developmental organization of the structural connectome in fetuses with corpus callosum agenesis.

    Science.gov (United States)

    Jakab, András; Kasprian, Gregor; Schwartz, Ernst; Gruber, Gerlinde Maria; Mitter, Christian; Prayer, Daniela; Schöpf, Veronika; Langs, Georg

    2015-05-01

    Agenesis of the corpus callosum is a model disease for disrupted connectivity of the human brain, in which the pathological formation of interhemispheric fibers results in subtle to severe cognitive deficits. Postnatal studies suggest that the characteristic abnormal pathways in this pathology are compensatory structures that emerge via neural plasticity. We challenge this hypothesis and assume a globally different network organization of the structural interconnections already in the fetal acallosal brain. Twenty fetuses with isolated corpus callosum agenesis with or without associated malformations were enrolled and fiber connectivity among 90 brain regions was assessed using in utero diffusion tensor imaging and streamline tractography. Macroscopic scale connectomes were compared to 20 gestational age-matched normally developing fetuses with multiple granularity of network analysis. Gradually increasing connectivity strength and tract diffusion anisotropy during gestation were dominant in antero-posteriorly running paramedian and antero-laterally running aberrant pathways, and in short-range connections in the temporoparietal regions. In fetuses with associated abnormalities, more diffuse reduction of cortico-cortical and cortico-subcortical connectivity was observed than in cases with isolated callosal agenesis. The global organization of anatomical networks consisted of less segregated nodes in acallosal brains, and hubs of dense connectivity, such as the thalamus and cingulate cortex, showed reduced network centrality. Acallosal fetal brains show a globally altered connectivity network structure compared to normals. Besides the previously described Probst and sigmoid bundles, we revealed a prenatally differently organized macroconnectome, dominated by increased connectivity. These findings provide evidence that abnormal pathways are already present during at early stages of fetal brain development in the majority of cerebral white matter.

  10. Quantitative trait loci for interhemispheric commissure development and social behaviors in the BTBR T⁺ tf/J mouse model of autism.

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    Dorothy M Jones-Davis

    Full Text Available BACKGROUND: Autism and Agenesis of the Corpus Callosum (AgCC are interrelated behavioral and anatomic phenotypes whose genetic etiologies are incompletely understood. We used the BTBR T⁺ tf/J (BTBR strain, exhibiting fully penetrant AgCC, a diminished hippocampal commissure, and abnormal behaviors that may have face validity to autism, to study the genetic basis of these disorders. METHODS: We generated 410 progeny from an F2 intercross between the BTBR and C57BL/6J strains. The progeny were phenotyped for social behaviors (as juveniles and adults and commisural morphology, and genotyped using 458 markers. Quantitative trait loci (QTL were identified using genome scans; significant loci were fine-mapped, and the BTBR genome was sequenced and analyzed to identify candidate genes. RESULTS: Six QTL meeting genome-wide significance for three autism-relevant behaviors in BTBR were identified on chromosomes 1, 3, 9, 10, 12, and X. Four novel QTL for commissural morphology on chromosomes 4, 6, and 12 were also identified. We identified a highly significant QTL (LOD score = 20.2 for callosal morphology on the distal end of chromosome 4. CONCLUSIONS: We identified several QTL and candidate genes for both autism-relevant traits and commissural morphology in the BTBR mouse. Twenty-nine candidate genes were associated with synaptic activity, axon guidance, and neural development. This is consistent with a role for these processes in modulating white matter tract development and aspects of autism-relevant behaviors in the BTBR mouse. Our findings reveal candidate genes in a mouse model that will inform future human and preclinical studies of autism and AgCC.

  11. 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.

  12. The value of fast MR imaging as an adjunct to ultrasound in prenatal diagnosis

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    Breysem, L.; Bosmans, H.; Dymarkowski, S.; Demaerel, P.; Vanbeckevoort, D.; Smet, M. [Department of Radiology, University Hospitals, Herestraat 49, 3000, Leuven (Belgium); Schoubroeck, D.Van; Witters, I.; Deprest, J. [Department of Obstetrics and Gynecology, University Hospitals, Herestraat 49, 3000, Leuven (Belgium); Vanhole, C.; Casaer, P. [Department of Pediatrics, University Hospitals, Herestraat 49, 3000, Leuven (Belgium)

    2003-07-01

    The aim of this study was to evaluate the role of MR imaging of the fetus to improve sonographic prenatal diagnosis of congenital anomalies. In 40 fetuses (not consecutive cases) with an abnormality diagnosed with ultrasound, additional MR imaging was performed. The basic sequence was a T2-weighted single-shot half Fourier (HASTE) technique. Head, neck, spinal, thoracic, urogenital, and abdominal fetal pathologies were found. This retrospective, observational study compared MR imaging findings with ultrasonographic findings regarding detection, topography, and etiology of the pathology. The MR findings were evaluated as superior, equal to, or inferior compared with US, in consent with the referring gynecologists. The role of these findings in relation to pregnancy management was studied and compared with postnatal follow-up in 30 of 40 babies. Fetal MRI technique was successful in 36 of 39 examinations and provided additional information in 21 of 40 fetuses (one twin pregnancy with two members to evaluate). More precise anatomy and location of fetal pathology (20 of 40 cases) and additional etiologic information (8 of 40 cases) were substantial advantages in cerebrospinal abnormalities [ventriculomegaly, encephalocele, vein of Galen malformation, callosal malformations, meningo(myelo)cele], in retroperitoneal abnormalities (lymphangioma, renal agenesis, multicystic renal dysplasia), and in neck/thoracic pathology [cervical cystic teratoma, congenital hernia diaphragmatica, congenital cystic adenomatoid lung malformation (CCAM)]. This improved parental counseling and pregnancy management in 15 pregnancies. In 3 cases, prenatal MRI findings did not correlate with prenatal ultrasonographic findings or neonatal diagnosis. The MRI provided a more detailed description and insight into fetal anatomy, pathology, and etiology in the vast majority of these selected cases. This improved prenatal parental counseling and postnatal therapeutic planning. (orig.)

  13. Agenesis of corpus callosum and emotional information processing in schizophrenia

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    Emmanuel eStip

    2012-02-01

    Full Text Available Corpus callosum (CC is essential in providing the integration of information related to perception and action within a subcortico-cortical network, thus supporting the generation of a unified experience about and reaction to changes in the environment. Its role in schizophrenia is yet to be fully elucidated, but there is accumulating evidence that there could be differences between patients and healthy controls regarding the morphology and function of CC, especially when individuals face emotionally laden information. Here, we report a case study of a patient with partial agenesis of corpus callosum (agCC patient with agenesis of the anterior aspect, above the genu and we provide a direct comparison with a group of patients with no apparent callosal damage (CC group regarding the brain activity during the processing of emotionally-laden information. We found that although the visual cortex activation in response to visual stimuli regardless of their emotional content was comparable in agCC patient and CC group both in terms of localization and intensity of activation, we observed a very large, non-specific and non-lateralized cerebral activation in the agCC patient, in contrast with the CC group, which showed a more lateralized and spatially localized activation, when the emotional content of the stimuli was considered. Further analysis of brain activity in the regions obtained in the CC group revealed that the agCC patient actually had an opposite activation pattern relative to most participants with no CC agenesis, indicating a dysfunctional response to these kind of stimuli, consistent with the clinical presentation of this particular patient. Our results seem to give support to the disconnection hypothesis which posits that the core symptoms of schizophrenia are related to aberrant connectivity between distinct brain areas, especially when faced with emotional stimuli, a fact consistent with the clinical tableau of this particular patient.

  14. Neuroimaging evidence of major morpho-anatomical and functional abnormalities in the BTBR T+TF/J mouse model of autism.

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    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

  15. Proverb comprehension in individuals with agenesis of the corpus callosum.

    Science.gov (United States)

    Rehmel, Jamie L; Brown, Warren S; Paul, Lynn K

    2016-09-01

    Comprehension of non-literal language involves multiple neural systems likely involving callosal connections. We describe proverb comprehension impairments in individuals with isolated agenesis of the corpus callosum (AgCC) and normal-range general intelligence. Experiment 1 compared Gorham Proverb Test (Gorham, 1956) performance in 19 adults with AgCC and 33 neurotypical control participants of similar age, sex, and intelligence. Experiment 2 used the Proverbs subtest of the Delis-Kaplan Executive Function System (D-KEFS, 2001) to compare 19 adults with AgCC and 17 control participants with similar age, sex, and intelligence. Gorham Proverbs performance was impaired in the AgCC group for both the free-response and multiple-choice tasks. On the D-KEFS proverbs test, the AgCC group performed significantly worse on the free-response task (and all derivative scores) despite normal levels of performance on the multiple-choice task. Covarying verbal intelligence did not alter these outcomes. However, covarying a measure of non-literal language comprehension considerably reduced group differences in proverb comprehension on the Gorham test, but had little effect on the D-KEFS group differences. The difference between groups seemed to be greatest when participants had to generate their own interpretation (free response), or in the multiple choice format when the test included many proverbs that were likely to be less familiar. Taken together, the results of this study clearly show that proverb comprehension is diminished in individuals with AgCC compared to their peers.

  16. Foliar response of an Ailanthus altissima clone in two sites with different levels of ozone-pollution

    Energy Technology Data Exchange (ETDEWEB)

    Gravano, Elisabetta; Giulietti, Valentina; Desotgiu, Rosanna; Bussotti, Filippo; Grossoni, Paolo; Gerosa, Giacomo; Tani, Corrado

    2003-01-01

    Ozone sensitivity of Ailanthus altissima leaves is due to low leaf density and large intercellular spaces. - Potted plants of Ailanthus altissima, produced by root suckers coming from a single symptomatic mother tree, were placed in two sites in the vicinity of Florence (central Italy), with different levels of ozone pollution. These plants were kept in well watered conditions during the period May-September 1999. In the high pollution site (Settignano-SET) the level of ozone exposure (AOT40) reached at the end of the season a value of 31 ppm h, whereas in the 'low pollution' site (Cascine-CAS) the exposure to ozone was 11 ppm h. A. altissima showed foliar symptoms in early July at SET and in the second half of July at CAS when exposure values reached 5 ppm h at both sites. However, at the end of August the conditions of the plantlets were rather similar in both sites. Microscopic and ultrastructural analysis were performed at the first onset of symptoms at SET (the CAS leaflets were asymptomatic). Observing the upper leaf surface where the brown stipples were visible, it was found that the cells of the palisade mesophyll displayed loss of chlorophyll and the organelles in the cytoplasm were damaged. Swelling of thylacoids was observed in the CAS leaflets, thus indicating the possible onset of a pre-visual damage. The injured cells were separated from the healthy ones by a layer of callose. We conclude that the sensitivity to ozone of A. altissima leaves is related to its leaf structure, with low leaf density and large intercellular spaces. Cell walls, as well as acting as mechanical barriers against the spread of ozone within the cell, also provide important detoxifying processes.

  17. Ammonium-related metabolic changes affect somatic embryogenesis in pumpkin (Cucurbita pepo L.).

    Science.gov (United States)

    Mihaljević, Snježana; Radić, Sandra; Bauer, Nataša; Garić, Rade; Mihaljević, Branka; Horvat, Gordana; Leljak-Levanić, Dunja; Jelaska, Sibila

    2011-11-01

    Somatic embryogenesis in pumpkin can be induced on auxin-containing medium and also on hormone-free medium containing 1mM ammonium (NH(4)(+)) as the sole source of nitrogen. Growth of NH(4)(+)-induced embryogenic tissue was slow and caused considerable acidification of the culture medium. Small spherical cells with dense cytoplasma formed proembryogenic cell clusters that could not develop into late stage embryos. Buffering of NH(4)(+) medium with 25mM 2-(N-morpholino)-ethane-sulfonic acid enhanced tissue proliferation, but no further differentiation was observed. Later stage embryos developed only after re-supply of nitrogen in form of nitrate or l-glutamine. Effects of nitrogen status and pH of culture media on ammonium assimilation were analyzed by following the activity of glutamine synthetase (GS) in relation to phenylalanine ammonia-lyase (PAL). Increased activity of GS and PAL in NH(4)(+) induced tissue coincided with significantly higher activity of stress-related enzymes superoxide dismutase (SOD) and soluble peroxidase (POD), indicating oxidative stress response of embryogenic tissue to NH(4)(+) as the sole source of nitrogen. In addition, considerable increase was observed in callose accumulation and esterase activity, the early markers of somatic embryogenesis. Activity of stress-related enzymes decreased after the re-supply of nitrate (20mM) or Gln (10mM) in combination with NH(4)(+) (1mM), which subsequently triggered globular embryo development. Together, these results suggest that stress responses, as affected by nitrogen supply, contribute to the regulation of embryogenic competence in pumpkin.

  18. Symmetric pollen mitosis I and suppression of pollen mitosis II prevent pollen development in Brachiaria jubata (Gramineae

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    C. Risso-Pascotto

    2005-11-01

    Full Text Available Microsporogenesis and pollen development were analyzed in a tetraploid (2n = 4x = 36 accession of the forage grass Brachiaria jubata (BRA 007820 from the Embrapa Beef Cattle Brachiaria collection that showed partial male sterility. Microsporocytes and pollen grains were prepared by squashing and staining with 0.5% propionic carmine. The meiotic process was typical of polyploids, with precocious chromosome migration to the poles and laggards in both meiosis I and II, resulting in tetrads with micronuclei in some microspores. After callose dissolution, microspores were released into the anther locule and appeared to be normal. Although each microspore initiated its differentiation into a pollen grain, in 11.1% of them nucleus polarization was not observed, i.e., pollen mitosis I was symmetric and the typical hemispherical cell plate was not detected. After a central cytokinesis, two equal-sized cells showing equal chromatin condensation and the same nuclear shape and size were formed. Generative cells and vegetative cells could not be distinguished. These cells did not undergo the second pollen mitosis and after completion of pollen wall synthesis each gave rise to a sterile and uninucleate pollen grain. The frequency of abnormal pollen mitosis varied among flowers and also among inflorescences. All plants were equally affected. The absence of fertile sperm cells in a considerable amount of pollen grains in this accession of B. jubata may compromise its use in breeding and could explain, at least in part, why seed production is low when compared with the amount of flowers per raceme.

  19. Mild encephalitis/encephalopathy with a reversible splenial lesion in children.

    Science.gov (United States)

    Liptai, Zoltán; Ivády, Balázs; Barsi, Péter; Várallyay, György; Rudas, Gábor; Fogarasi, András

    2013-01-30

    Authors, most of them Japanese, have recently published an increasing number of articles on mild encephalitis/encephalopathy with a reversible splenial lesion. We report on two new white European patients and compare published data with our own observations. A 15-year-old girl developed headache, fever, dizziness, vomiting and nuchal rigidity over four days. CSF showed elevated protein and cell count, with the lowest serum Na being 131 mmol/L. MRI on day seven was normal, but she remained febrile, had cerebral edema and episodes of confusion. MRI on day 11 showed a small T2-hyperintense lesion with restricted diffusion in the callosal splenium. Adenoviral infection was proved, and the girl underwent a protracted course of recovery. MRI signal changes improved in six days and disappeared after four months. A 12.5-year-old girl developed headache, lethargy, drowsiness and vomiting. On day five she experienced right-sided numbness, weakness and inability to speak which lasted 12 hours. She was confused and disoriented. MRI disclosed a tiny area of increased T2-signal and restricted diffusion in the splenium. Serum Na was 133 mmol/L, CSF cell count and protein was markedly elevated, and enteroviral infection was detected. Echocardiography showed no changes predisposing to clot formation and no thrombophilia was found. Her symptoms resolved in a week and MRI was normal two months later. These two non-epileptic children increase the small number of white European patients with MERS reported so far. Both had hyponatremia and encephalitis and patient 2 had transient ischemic attack, possibly due to the cerebral edema also resulting in the splenial lesion.

  20. Translocation and functional analysis of Pseudomonas savastanoi pv. savastanoi NCPPB 3335 type III secretion system effectors reveals two novel effector families of the Pseudomonas syringae complex.

    Science.gov (United States)

    Matas, Isabel M; Castañeda-Ojeda, M Pilar; Aragón, Isabel M; Antúnez-Lamas, María; Murillo, Jesús; Rodríguez-Palenzuela, Pablo; López-Solanilla, Emilia; Ramos, Cayo

    2014-05-01

    Pseudomonas savastanoi pv. savastanoi NCPPB 3335 causes olive knot disease and is a model pathogen for exploring bacterial infection of woody hosts. The type III secretion system (T3SS) effector repertoire of this strain includes 31 effector candidates plus two novel candidates identified in this study which have not been reported to translocate into plant cells. In this work, we demonstrate the delivery of seven NCPPB 3335 effectors into Nicotiana tabacum leaves, including three proteins from two novel families of the P. syringae complex effector super-repertoire (HopBK and HopBL), one of which comprises two proteins (HopBL1 and HopBL2) that harbor a SUMO protease domain. When delivered by P. fluorescens heterologously expressing a P. syringae T3SS, all seven effectors were found to suppress the production of defense-associated reactive oxygen species. Moreover, six of these effectors, including the truncated versions of HopAA1 and HopAZ1 encoded by NCPPB 3335, suppressed callose deposition. The expression of HopAZ1 and HopBL1 by functionally effectorless P. syringae pv. tomato DC3000D28E inhibited the hypersensitive response in tobacco and, additionally, expression of HopBL2 by this strain significantly increased its competitiveness in N. benthamiana. DNA sequences encoding HopBL1 and HopBL2 were uniquely detected in a collection of 31 P. savastanoi pv. savastanoi strains and other P. syringae strains isolated from woody hosts, suggesting a relevant role of these two effectors in bacterial interactions with olive and other woody plants.

  1. 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.

    Science.gov (United States)

    Sinha, Dipanwita; Gupta, Mahesh Kumar; Patel, Hitendra Kumar; Ranjan, Ashish; Sonti, Ramesh V

    2013-01-01

    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.

  2. Evolutionary appearance of Von Economo’s Neurons in the mammalian cerebral cortex

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    Franco eCauda

    2014-03-01

    Full Text Available 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 fMRI data. The recent finding of VENs in the anterior insula of the macaque opens the way to new insights and experimental investigatio

  3. 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.

  4. Altered Gray Matter Volume and School Age Anxiety in Children Born Late Preterm

    Science.gov (United States)

    Rogers, Cynthia E; Barch, Deanna M; Sylvester, Chad M; Pagliaccio, David; Harms, Michael P; Botteron, Kelly N; Luby, Joan L

    2014-01-01

    Objectives To determine if late preterm (LP) children differ from full term (FT) children in volumes of the cortex, hippocampus, corpus callosum, or amygdala and whether these differences are associated with anxiety symptoms at school-age. Study design LP children born between 34 and 36 weeks gestation and FT children born between 39 and 41 weeks gestation from a larger longitudinal cohort had MRI scans at school-age. Brain volumes, cortical surface area and thickness measures were obtained. Anxiety symptoms were assessed using a structured diagnostic interview annually beginning at preschool-age and following the MRI. Results LP children (n=21) had a smaller percentage of total, right parietal, and right temporal lobe gray matter volume than FT children (n=87). There were no differences in hippocampal, callosal, or amygdala volumes or cortical thickness. LP children also had a relative decrease in right parietal lobe cortical surface area. LP children had greater anxiety symptoms over all assessments. The relationship between late prematurity and school-age anxiety symptoms was mediated by the relative decrease in right temporal lobe volume. Conclusion LP children, comprising 70% of preterm children, are also at increased risk for altered brain development particularly in the right temporal and parietal cortices. Alterations in the right temporal lobe cortical volume may underlie the increased rate of anxiety symptoms among these LP children. These findings suggest that LP delivery may disrupt temporal and parietal cortical development that persists until school-age with the right temporal lobe conferring risk for elevated anxiety symptoms. PMID:25108541

  5. The lectin receptor kinase LecRK-I.9 is a novel Phytophthora resistance component and a potential host target for a RXLR effector.

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    Klaas Bouwmeester

    2011-03-01

    Full Text Available In plants, an active defense against biotrophic pathogens is dependent on a functional continuum between the cell wall (CW and the plasma membrane (PM. It is thus anticipated that proteins maintaining this continuum also function in defense. The legume-like lectin receptor kinase LecRK-I.9 is a putative mediator of CW-PM adhesions in Arabidopsis and is known to bind in vitro to the Phytophthora infestans RXLR-dEER effector IPI-O via a RGD cell attachment motif present in IPI-O. Here we show that LecRK-I.9 is associated with the plasma membrane, and that two T-DNA insertions lines deficient in LecRK-I.9 (lecrk-I.9 have a 'gain-of-susceptibility' phenotype specifically towards the oomycete Phytophthora brassicae. Accordingly, overexpression of LecRK-I.9 leads to enhanced resistance to P. brassicae. A similar 'gain-of-susceptibility' phenotype was observed in transgenic Arabidopsis lines expressing ipiO (35S-ipiO1. This phenocopy behavior was also observed with respect to other defense-related functions; lecrk-I.9 and 35S-ipiO1 were both disturbed in pathogen- and MAMP-triggered callose deposition. By site-directed mutagenesis, we demonstrated that the RGD cell attachment motif in IPI-O is not only essential for disrupting the CW-PM adhesions, but also for disease suppression. These results suggest that destabilizing the CW-PM continuum is one of the tactics used by Phytophthora to promote infection. As countermeasure the host may want to strengthen CW-PM adhesions and the novel Phytophthora resistance component LecRK-I.9 seems to function in this process.

  6. The lectin receptor kinase LecRK-I.9 is a novel Phytophthora resistance component and a potential host target for a RXLR effector.

    Science.gov (United States)

    Bouwmeester, Klaas; de Sain, Mara; Weide, Rob; Gouget, Anne; Klamer, Sofieke; Canut, Herve; Govers, Francine

    2011-03-01

    In plants, an active defense against biotrophic pathogens is dependent on a functional continuum between the cell wall (CW) and the plasma membrane (PM). It is thus anticipated that proteins maintaining this continuum also function in defense. The legume-like lectin receptor kinase LecRK-I.9 is a putative mediator of CW-PM adhesions in Arabidopsis and is known to bind in vitro to the Phytophthora infestans RXLR-dEER effector IPI-O via a RGD cell attachment motif present in IPI-O. Here we show that LecRK-I.9 is associated with the plasma membrane, and that two T-DNA insertions lines deficient in LecRK-I.9 (lecrk-I.9) have a 'gain-of-susceptibility' phenotype specifically towards the oomycete Phytophthora brassicae. Accordingly, overexpression of LecRK-I.9 leads to enhanced resistance to P. brassicae. A similar 'gain-of-susceptibility' phenotype was observed in transgenic Arabidopsis lines expressing ipiO (35S-ipiO1). This phenocopy behavior was also observed with respect to other defense-related functions; lecrk-I.9 and 35S-ipiO1 were both disturbed in pathogen- and MAMP-triggered callose deposition. By site-directed mutagenesis, we demonstrated that the RGD cell attachment motif in IPI-O is not only essential for disrupting the CW-PM adhesions, but also for disease suppression. These results suggest that destabilizing the CW-PM continuum is one of the tactics used by Phytophthora to promote infection. As countermeasure the host may want to strengthen CW-PM adhesions and the novel Phytophthora resistance component LecRK-I.9 seems to function in this process.

  7. Phenotypic and histochemical traits of the interaction between Plasmopara viticola and resistant or susceptible grapevine varieties

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    Toffolatti Silvia

    2012-08-01

    Full Text Available Abstract Background Grapevine downy mildew, caused by Plasmopara viticola, is a very serious disease affecting mainly Vitis vinifera cultivated varieties around the world. Breeding for resistance through the crossing with less susceptible species is one of the possible means to reduce the disease incidence and the application of fungicides. The hybrid Bianca and some of its siblings are considered very promising but their resistance level can vary depending on the pathogen strain. Moreover, virulent strains characterized by high fitness can represent a potential threat to the hybrid cultivation. Results The host response and the pathogen virulence were quantitatively assessed by artificially inoculating cv Chardonnay, cv Bianca and their siblings with P. viticola isolates derived from single germinating oospores collected in various Italian viticultural areas. The host phenotypes were classified as susceptible, intermediate and resistant, according to the Area Under the Disease Progress Curve caused by the inoculated strain. Host responses in cv Bianca and its siblings significantly varied depending on the P. viticola isolates, which in turn differed in their virulence levels. The fitness of the most virulent strain did not significantly vary on the different hybrids including Bianca in comparison with the susceptible cv Chardonnay, suggesting that no costs are associated with virulence. Among the individual fitness components, only sporangia production was significantly reduced in cv Bianca and in some hybrids. Comparative histological analysis revealed differences between susceptible and resistant plants in the pathogen diffusion and cytology from 48 h after inoculation onwards. Defence mechanisms included callose depositions in the infected stomata, increase in peroxidase activity, synthesis of phenolic compounds and flavonoids and the necrosis of stomata and cells immediately surrounding the point of invasion and determined alterations in

  8. 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.)

  9. Induced systemic resistance responses in perennial ryegrass against Magnaporthe oryzae elicited by semi-purified surfactin lipopeptides and live cells of Bacillus amyloliquefaciens.

    Science.gov (United States)

    Rahman, Alamgir; Uddin, Wakar; Wenner, Nancy G

    2015-08-01

    The suppressive ability of several strains of cyclic lipopeptide-producing Bacillus rhizobacteria to grey leaf spot disease caused by Magnaporthe oryzae has been documented previously; however, the underlying mechanism(s) involved in the induced systemic resistance (ISR) activity in perennial ryegrass (Lolium perenne L.) remains unknown. Root-drench application of solid-phase extraction (SPE)-enriched surfactin and live cells of mutant Bacillus amyloliquefaciens strain FZB42-AK3 (produces surfactin, but not bacillomycin D and fengycin) significantly reduced disease incidence and severity on perennial ryegrass. The application of the treatments revealed a pronounced multilayered ISR defence response activation via timely and enhanced accumulation of hydrogen peroxide (H2O2), elevated cell wall/apoplastic peroxidase activity, and deposition of callose and phenolic/polyphenolic compounds underneath the fungal appressoria in naïve leaves, which was significantly more intense in treated plants than in mock-treated controls. Moreover, a hypersensitive response (HR)-type reaction and enhanced expression of LpPrx (Prx, peroxidase), LpOXO4 (OXO, oxalate oxidase), LpPAL (PAL, phenylalanine ammonia lyase), LpLOXa (LOX, lipoxygenase), LpTHb (putative defensin) and LpDEFa (DEFa, putative defensin) in perennial ryegrass were associated with SPE-enriched surfactin and live AK3 cell treatments, acting as a second layer of defence when pre-invasive defence responses failed. The results indicate that ISR activity following surfactin perception may sensitize H2O2 -mediated defence responses, thereby providing perennial ryegrass with enhanced protection against M. oryzae.

  10. 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.

  11. Co-silencing of tomato S-adenosylhomocysteine hydrolase genes confers increased immunity against Pseudomonas syringae pv. tomato DC3000 and enhanced tolerance to drought stress

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    Li Xiao Hui

    2015-09-01

    Full Text Available S-adenosylhomocysteine hydrolase (SAHH, catalyzing the reversible hydrolysis of S-adenosylhomocysteine to adenosine and homocysteine, is a key enzyme that maintain the cellular methylation potential in all organisms. We report here the biological functions of tomato SlSAHHs in stress response. The tomato genome contains three SlSAHH genes that encode SlSAHH proteins with high level of sequence identity. qRT-PCR analysis revealed that SlSAHHs responded with distinct expression induction patterns to Pseudomonas syringae pv. tomato (Pst DC3000 and Botrytis cinerea as well as to defense signaling hormones such as salicylic acid, jasmonic acid and a precursor of ethylene. Virus-induced gene silencing-based knockdown of individual SlSAHH gene did not affect the growth performance and the response to Pst DC3000. However, co-silencing of three SlSAHH genes using a conserved sequence led to significant inhibition of vegetable growth. The SlSAHH-co-silenced plants displayed increased resistance to Pst DC3000 but did not alter the resistance to B. cinerea. Co-silencing of SlSAHHs resulted in constitutively activated defense responses including elevated SA level, upregulated expression of defense-related and PAMP-triggered immunity marker genes and increased callose deposition and H2O2 accumulation. Furthermore, the SlSAHH-co-silenced plants also exhibited enhanced drought stress tolerance although they had relatively small roots. These data demonstrate that, in addition to the functions in growth and development, SAHHs also play important roles in regulating biotic and abiotic stress responses in plants.

  12. Co-silencing of tomato S-adenosylhomocysteine hydrolase genes confers increased immunity against Pseudomonas syringae pv. tomato DC3000 and enhanced tolerance to drought stress.

    Science.gov (United States)

    Li, Xiaohui; Huang, Lei; Hong, Yongbo; Zhang, Yafen; Liu, Shixia; Li, Dayong; Zhang, Huijuan; Song, Fengming

    2015-01-01

    S-adenosylhomocysteine hydrolase (SAHH), catalyzing the reversible hydrolysis of S-adenosylhomocysteine (SAH) to adenosine and homocysteine, is a key enzyme that maintain the cellular methylation potential in all organisms. We report here the biological functions of tomato SlSAHHs in stress response. The tomato genome contains three SlSAHH genes that encode SlSAHH proteins with high level of sequence identity. qRT-PCR analysis revealed that SlSAHHs responded with distinct expression induction patterns to Pseudomonas syringae pv. tomato (Pst) DC3000 and Botrytis cinerea as well as to defense signaling hormones such as salicylic acid, jasmonic acid and a precursor of ethylene. Virus-induced gene silencing-based knockdown of individual SlSAHH gene did not affect the growth performance and the response to Pst DC3000. However, co-silencing of three SlSAHH genes using a conserved sequence led to significant inhibition of vegetable growth. The SlSAHH-co-silenced plants displayed increased resistance to Pst DC3000 but did not alter the resistance to B. cinerea. Co-silencing of SlSAHHs resulted in constitutively activated defense responses including elevated SA level, upregulated expression of defense-related and PAMP-triggered immunity marker genes and increased callose deposition and H2O2 accumulation. Furthermore, the SlSAHH-co-silenced plants also exhibited enhanced drought stress tolerance although they had relatively small roots. These data demonstrate that, in addition to the functions in growth and development, SAHHs also play important roles in regulating biotic and abiotic stress responses in plants.

  13. Neonatal white matter abnormalities an important predictor of neurocognitive outcome for very preterm children.

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    Lianne J Woodward

    Full Text Available BACKGROUND: Cerebral white matter abnormalities on term MRI are a strong predictor of motor disability in children born very preterm. However, their contribution to cognitive impairment is less certain. OBJECTIVE: Examine relationships between the presence and severity of cerebral white matter abnormalities on neonatal MRI and a range of neurocognitive outcomes assessed at ages 4 and 6 years. DESIGN/METHODS: The study sample consisted of a regionally representative cohort of 104 very preterm (≤32 weeks gestation infants born from 1998-2000 and a comparison group of 107 full-term infants. At term equivalent, all preterm infants underwent a structural MRI scan that was analyzed qualitatively for the presence and severity of cerebral white matter abnormalities, including cysts, signal abnormalities, loss of white matter volume, ventriculomegaly, and corpus callosal thinning/myelination. At corrected ages 4 and 6 years, all children underwent a comprehensive neurodevelopmental assessment that included measures of general intellectual ability, language development, and executive functioning. RESULTS: At 4 and 6 years, very preterm children without cerebral white matter abnormalities showed no apparent neurocognitive impairments relative to their full-term peers on any of the domain specific measures of intelligence, language, and executive functioning. In contrast, children born very preterm with mild and moderate-to-severe white matter abnormalities were characterized by performance impairments across all measures and time points, with more severe cerebral abnormalities being associated with increased risks of cognitive impairment. These associations persisted after adjustment for gender, neonatal medical risk factors, and family social risk. CONCLUSIONS: Findings highlight the importance of cerebral white matter connectivity for later intact cognitive functioning amongst children born very preterm. Preterm born children without cerebral white

  14. Cross-hemispheric collaboration and segregation associated with task difficulty as revealed by structural and functional connectivity.

    Science.gov (United States)

    Davis, Simon W; Cabeza, Roberto

    2015-05-27

    Although it is known that brain regions in one hemisphere may interact very closely with their corresponding contralateral regions (collaboration) or operate relatively independent of them (segregation), the specific brain regions (where) and conditions (how) associated with collaboration or segregation are largely unknown. We investigated these issues using a split field-matching task in which participants matched the meaning of words or the visual features of faces presented to the same (unilateral) or to different (bilateral) visual fields. Matching difficulty was manipulated by varying the semantic similarity of words or the visual similarity of faces. We assessed the white matter using the fractional anisotropy (FA) measure provided by diffusion tensor imaging (DTI) and cross-hemispheric communication in terms of fMRI-based connectivity between homotopic pairs of cortical regions. For both perceptual and semantic matching, bilateral trials became faster than unilateral trials as difficulty increased (bilateral processing advantage, BPA). The study yielded three novel findings. First, whereas FA in anterior corpus callosum (genu) correlated with word-matching BPA, FA in posterior corpus callosum (splenium-occipital) correlated with face-matching BPA. Second, as matching difficulty intensified, cross-hemispheric functional connectivity (CFC) increased in domain-general frontopolar cortex (for both word and face matching) but decreased in domain-specific ventral temporal lobe regions (temporal pole for word matching and fusiform gyrus for face matching). Last, a mediation analysis linking DTI and fMRI data showed that CFC mediated the effect of callosal FA on BPA. These findings clarify the mechanisms by which the hemispheres interact to perform complex cognitive tasks.

  15. An immunity-triggering effector from the Barley smut fungus Ustilago hordei resides in an Ustilaginaceae-specific cluster bearing signs of transposable element-assisted evolution.

    Science.gov (United States)

    Ali, Shawkat; Laurie, John D; Linning, Rob; Cervantes-Chávez, José Antonio; Gaudet, Denis; Bakkeren, Guus

    2014-07-01

    The basidiomycete smut fungus Ustilago hordei was previously shown to comprise isolates that are avirulent on various barley host cultivars. Through genetic crosses we had revealed that a dominant avirulence locus UhAvr1 which triggers immunity in barley cultivar Hannchen harboring resistance gene Ruh1, resided within an 80-kb region. DNA sequence analysis of this genetically delimited region uncovered the presence of 7 candidate secreted effector proteins. Sequence comparison of their coding sequences among virulent and avirulent parental and field isolates could not distinguish UhAvr1 candidates. Systematic deletion and complementation analyses revealed that UhAvr1 is UHOR_10022 which codes for a small effector protein of 171 amino acids with a predicted 19 amino acid signal peptide. Virulence in the parental isolate is caused by the insertion of a fragment of 5.5 kb with similarity to a common U. hordei transposable element (TE), interrupting the promoter of UhAvr1 and thereby changing expression and hence recognition of UhAVR1p. This rearrangement is likely caused by activities of TEs and variation is seen among isolates. Using GFP-chimeric constructs we show that UhAvr1 is induced only in mated dikaryotic hyphae upon sensing and infecting barley coleoptile cells. When infecting Hannchen, UhAVR1p causes local callose deposition and the production of reactive oxygen species and necrosis indicative of the immune response. UhAvr1 does not contribute significantly to overall virulence. UhAvr1 is located in a cluster of ten effectors with several paralogs and over 50% of TEs. This cluster is syntenous with clusters in closely-related U. maydis and Sporisorium reilianum. In these corn-infecting species, these clusters harbor however more and further diversified homologous effector families but very few TEs. This increased variability may have resulted from past selection pressure by resistance genes since U. maydis is not known to trigger immunity in its corn host.

  16. Molecular Scanning and Morpho-Physiological Dissection of Component Mechanism in Lens Species in Response to Aluminium Stress

    Science.gov (United States)

    Singh, Dharmendra; Pal, Madan; Singh, Chandan Kumar; Taunk, Jyoti; Jain, Priyanka; Chaturvedi, Ashish Kumar; Maurya, Sadhana; Karwa, Sourabh; Singh, Rajendra; Tomar, Ram Sewak Singh; Nongthombam, Rita; Chongtham, Nandini; Singh, Moirangthem Premjit

    2016-01-01

    Aluminium (Al) stress was imposed on 285 lentil genotypes at seedling stage under hydroponics to study its effects on morpho-physiological traits where resistant cultigens and wilds showed minimum reduction in root and shoot length and maximum root re-growth (RRG) after staining. Molecular assortment based on 46 simple sequence repeat (SSR) markers clustered the genotypes into 11 groups, where wilds were separated from the cultigens. Genetic diversity and polymorphism information content (PIC) varied between 0.148–0.775 and 0.140–0.739, respectively. Breeding lines which were found to be most resistant (L-7903, L-4602); sensitive cultivars (BM-4, L-4147) and wilds ILWL-185 (resistant), ILWL-436 (sensitive) were grouped into different clusters. These genotypes were also separated on the basis of population structure and Jaccard’s similarity index and analysed to study Al resistance mechanism through determination of different attributes like localization of Al and callose, lipid peroxidation, secretion of organic acids and production of antioxidant enzymes. In contrast to sensitive genotypes, in resistant ones most of the Al was localized in the epidermal cells, where its movement to apoplastic region was restricted due to release of citrate and malate. Under acidic field conditions, resistant genotypes produced maximum seed yield/plant as compared to sensitive genotypes at two different locations i.e. Imphal, Manipur, India and Basar, Arunanchal Pradesh, India during 2012–13, 2013–14 and 2014–15. These findings suggest that Al stress adaptation in lentil is through exclusion mechanism and hybridization between the contrasting genotypes from distinct clusters can help in development of resistant varieties. PMID:27467074

  17. UDP-glucose pyrophosphorylase2 (OsUgp2),a pollen-preferential gene in rice, plays a critical role in starch accumulation during pollen maturation

    Institute of Scientific and Technical Information of China (English)

    MU Hong; KE JianHao; LIU Wei; ZHUANG ChuXiong; YIP WingKin

    2009-01-01

    UDP-glucose pyrophosphorylase (UGPase) is predominantly present and plays significant role in car-bohydrate metabolism in plants. Two homologous UGPase genes, OsUgp1 and OsUgp2, exist in rice genome. OsUgp1 has recently been reported to be essential for callose deposition during pollen mother cell and meiosis stages as well as for seed carbohydrate metabolism. In this study, a full-length cDNA of OsUgp2 was isolated from rice anther. Northern blot and RNA in situ hybridization indicated that the expression of OsUgp2 was preferentially in pollen and developmentally regulated. No tran-scripts were found in leaf, stem, lemma/palea, ripening grain and florets before the uninucleate micro-spore developmental stage, but a large quantity of OsUgp2 mRNA was found in pollen at the binucleate and mature stages. The immunolocalizaUon of OsUgp2 showed a similar expression pattern to that by RNA in situ hybridization. The function of OsUgp2 was investigated by dsRNA-mediated transcriptional gene silencing. The pollen fertility of 16 independent transgenic rice plants was found between 25%and 90%, which was correlated with the amount of OsUgp2 mRNA. The results of morphological changes and starch variation during pollen development in transgenic rice showed that the abnormal feature of pollen development appeared after the uninucleate microspore stage. Starch failed to accu-mulate in pollen and thus led to sterile pollens. These results demonstrated that OsUgp2 is a pol-len-preferential "late gone" and plays a key role during pollen maturation, especially for starch accu-mulation. OsUgp2 complements OsUgpl to fulfill the UGPase's functions necessary for the full processof pollen development.

  18. Cdk5 is required for multipolar-to-bipolar transition during radial neuronal migration and proper dendrite development of pyramidal neurons in the cerebral cortex.

    Science.gov (United States)

    Ohshima, Toshio; Hirasawa, Motoyuki; Tabata, Hidenori; Mutoh, Tetsuji; Adachi, Tomoko; Suzuki, Hiromi; Saruta, Keiko; Iwasato, Takuji; Itohara, Shigeyoshi; Hashimoto, Mistuhiro; Nakajima, Kazunori; Ogawa, Masaharu; Kulkarni, Ashok B; Mikoshiba, Katsuhiko

    2007-06-01

    The mammalian cerebral cortex consists of six layers that are generated via coordinated neuronal migration during the embryonic period. Recent studies identified specific phases of radial migration of cortical neurons. After the final division, neurons transform from a multipolar to a bipolar shape within the subventricular zone-intermediate zone (SVZ-IZ) and then migrate along radial glial fibres. Mice lacking Cdk5 exhibit abnormal corticogenesis owing to neuronal migration defects. When we introduced GFP into migrating neurons at E14.5 by in utero electroporation, we observed migrating neurons in wild-type but not in Cdk5(-/-) embryos after 3-4 days. Introduction of the dominant-negative form of Cdk5 into the wild-type migrating neurons confirmed specific impairment of the multipolar-to-bipolar transition within the SVZ-IZ in a cell-autonomous manner. Cortex-specific Cdk5 conditional knockout mice showed inverted layering of the cerebral cortex and the layer V and callosal neurons, but not layer VI neurons, had severely impaired dendritic morphology. The amount of the dendritic protein Map2 was decreased in the cerebral cortex of Cdk5-deficient mice, and the axonal trajectory of cortical neurons within the cortex was also abnormal. These results indicate that Cdk5 is required for proper multipolar-to-bipolar transition, and a deficiency of Cdk5 results in abnormal morphology of pyramidal neurons. In addition, proper radial neuronal migration generates an inside-out pattern of cerebral cortex formation and normal axonal trajectories of cortical pyramidal neurons.

  19. 马铃薯(延薯4号)小孢子发生的细胞学观察%Cytological Observation of Microsporogenesis in the Potato(Yanshu 4)

    Institute of Scientific and Technical Information of China (English)

    全雪丽; 玄春吉; 吴京姬; 许震宇

    2013-01-01

    采用常规石蜡切片法,在光学显微镜下观察了马铃薯延薯4号品种的小孢子发生和各时期的形态特征.结果表明:马铃薯延薯4号小孢子发育经历了造孢细胞、小孢子母细胞、四分体等时期.四分体属四面体型,缄毡层属分泌型.延薯4号小孢子表现高度不育,败育发生在四分体时期开始,其主要特征是四分体胼胝质不能适时降解,致使四分体持续时间较长,细胞内核收缩降解,形成形状不规则、空瘪的小孢子.%Morphology characters of microsporogenesis and developmental stage of potato (cultivar Yanshu 4) were observed under optical microscope with the method of paraffin sectioning.The results showed that microspore of Yanshu 4 developed sporogenous cell,microspore mother cell and tetrad.Tetrad and tapetum respectively belonged to tetrahedral and secretory.Microspore of Yanshu 4 showed highly sterile,abortion appeared at beginning of tetrad,and the main feature was tetrad callose could not timely degrade which caused longer tetrad stage,contraction and degradation of nuclear,and irregular and empty microspore.

  20. Label-Free Quantitative Proteomics of Embryogenic and Non-Embryogenic Callus during Sugarcane Somatic Embryogenesis.

    Directory of Open Access Journals (Sweden)

    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.

  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.

  2. Morphological features and associated anomalies of schizencephaly in the clinical population: detailed analysis of MR images

    Energy Technology Data Exchange (ETDEWEB)

    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

  3. The Xanthomonas campestris pv. vesicatoria Type-3 Effector XopB Inhibits Plant Defence Responses by Interfering with ROS Production.

    Directory of Open Access Journals (Sweden)

    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 is XopB which interferes with PTI, ETI and sugar-mediated defence responses, but the underlying molecular mechanisms and direct targets are unknown so far. Here, we examined the XopB-mediated suppression of plant defence responses in more detail. Infection of susceptible pepper plants with Xcv lacking xopB resulted in delayed symptom development compared to Xcv wild type infection concomitant with an increased formation of salicylic acid (SA and expression of pathogenesis-related (PR genes. Expression of xopB in Arabidopsis thaliana promoted the growth of the virulent Pseudomonas syringae pv. tomato (Pst DC3000 strain. This was paralleled by a decreased SA-pool and a lower induction of SA-dependent PR gene expression. The expression pattern of early flg22-responsive marker genes indicated that MAPK signalling was not altered in the presence of XopB. However, XopB inhibited the flg22-triggered burst of reactive oxygen species (ROS. Consequently, the transcript accumulation of AtOXI1, a ROS-dependent marker gene, was reduced in xopB-expressing Arabidopsis plants as well as callose deposition. The lower ROS production correlated with a low level of basal and flg22-triggered expression of apoplastic peroxidases and the NADPH oxidase RBOHD. Conversely, deletion of xopB in Xcv caused a higher production of ROS in leaves of susceptible pepper plants. Together our results demonstrate that XopB modulates ROS responses and might thereby compromise plant defence.

  4. The Relationship between Hydroxamates Cyclic Secretion from Maize and Its Tolerance to Aluminum%玉米异羟肟酸类物质的分泌与其耐铝性的关系

    Institute of Scientific and Technical Information of China (English)

    唐新莲; 郭添香; 高小凤; 黎晓峰; 顾明华

    2015-01-01

    Aluminum (Al) toxicity is a major limiting factor for plant growth on acid soils; plants have evolved different strategies to detoxify Al stress due to different growth environments. Elucidation of these strategies will help us generate crops with enhanced Al tolerance. Most land plants use secretion of organic acid anions, such as oxalate, citrate and malate in response to Al stress. However, little work has so far been reported on relationship between Al resistance and Al-induced exudation of hydroxamates cyclic from roots ofZea MaysL. varieties. In this study, fifty-six varieties of maize were used to study the relationship between hydroxamates cyclic and Al tolerance based on the root elongation, Al content, callose content and hydroxamates cyclic measured among these 56 varieties. Al could induce secretion of hydroxamates cyclic from roots of different maize varieties, and callose, Al content of root tips were also significantly increased after Al treatment. Furthermore, there was significantly positive correlation between the root elon-gation and Al-induced secretion of hydroxamates cyclic(rDIMBOA=0.4550**,rMBOA=0.6008**),whereas there was significantly negative correlation between the Al content and hydroxamates cyclic(rDIMBOA=-0.3542**,rMBOA=-0.4841**), and callose was also significantly positively related to hydroxamates cyclic (rDIMBOA=-0.3651**,rMBOA=-0.1351). Cluster analysis showed that Al-induced secretion of hydroxamates cyclic from 30 Al-tolerance varieties such as Taiyu No.11, Feiyu No.3 and so on were higher than those of 7 Al-sensitive varieties such as Zhengdan No.958, Beiyu No.2883 and so on. Our results suggested that the secretion of hydroxamates cyclic in roots could be a novel mechanism for some tolerance varieties to resist the to