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Sample records for altered functional properties

  1. Conjugation of D-glucosamine to bovine trypsin increases thermal stability and alters functional properties.

    Science.gov (United States)

    Gizurarson, Jóhann Grétar Kröyer; Filippusson, Hörður

    2015-01-01

    D-Glucosamine was conjugated to bovine trypsin by carbodiimide chemistry, involving a water-soluble carbodiimide and a succinimide ester, with the latter being to increase the yield of the conjugation. Mass spectrometric data suggested that several glycoforms were formed, with around 12 D-glucosamine moieties coupled to each trypsin molecule on average. The moieties were probably coupled to eight carboxyl groups (of glutamyl and aspartyl residues) and to four tyrosyl residues on the surface of the enzyme. The glycated trypsin possessed increased thermal stability. When compared with its unmodified counterpart, T50% was increased by 7 °C, thermal inactivation of the first step was increased 34%, and long-term stability assay revealed 71-times higher residual activity at 25 °C (without stabilizing Ca(2+) ions in aqueous buffer) after 67 days. Furthermore, resistance against autolysis was increased almost two-fold. Altered functional properties of the glycated trypsin were also observed. The glycated trypsin was found to become increasingly basophilic, and was found to be slightly structurally altered. This was indicated by 1.2 times higher catalytic efficiency (k(cat)/K(m)) than unmodified trypsin against the substrate N-α-benzoyl-L-arginine-p-nitroanilide. Circular dichroism spectropolarimetry suggested a minor change in spatial arrangement of α-helix/helices, resulting in an increased affinity of the glycated trypsin for this small synthetic substrate.

  2. Functional properties of butter oil made from bovine milk with experimentally altered fat composition.

    Science.gov (United States)

    Ortiz-Gonzalez, G; Jimenez-Flores, R; Bremmer, D R; Clark, J H; DePeters, E J; Schmidt, S J; Drackley, J K

    2007-11-01

    Modification of milk fat composition might be desirable to alter manufacturing characteristics or produce low saturated fat dairy products that more closely meet consumer dietary preferences. The aim of this research was to evaluate functional properties of butter oil obtained from milks with fat composition modified by altering the profile of long-chain fatty acids (FA) absorbed from the small intestine of cows. A control and 5 mixtures of long-chain free FA were infused into the abomasum of lactating dairy cows in a 6 x 6 Latin square design with 21-d periods. Treatments were 1) control (no FA infused), 2) mostly saturated FA (C16:C18 = 0.72), 3) low-linoleic palm FA (C16:C18 = 0.85), 4) palm FA (C16:C18 = 0.72), 5) soy FA (C16:C18 = 0.10), and 6) high-palmitic soy FA (C16:C18 = 0.68). All treatments included meat solubles and Tween 80 as emulsifiers. Solid fat content (from 0 to 40 degrees C), melting point, and force at fracture were determined in butter oil. Milk fat from cows infused with palm FA (treatment 4) exhibited functionality equal to or better than control butter oil. Infusion with palm FA increased amounts of triglyceride (TG) fractions with 48, 52, and 54 carbon numbers but decreased TG with 32, 34, 36, and 42 carbon numbers. Infusion with soy FA increased TG with 26, 38, 40, 52, and 54 carbon numbers but decreased TG with 34, 42, and 46 carbons. Infusion of the mostly saturated FA increased TG with 38, 50, 52, and 54 carbon numbers but decreased TG with 32, 34, and 42 carbon numbers. These TG groups were consistently correlated with functional properties of butter oils from different treatments. The content of palmitic acid is important for maintaining functionality in the presence of increased polyunsaturated FA. The composition of milk fat may be able to be optimized through nutritional manipulation of diets for dairy cows if the optimal composition of FA and TG is defined for a particular dairy product.

  3. Influence of diet-mediated maternal thyroid alterations on functional properties of turkey eggs.

    Science.gov (United States)

    Christensen, V L; Ort, J F

    1990-09-01

    Maternal thyroid status was altered by means of diet to determine its effect on functional properties of turkey eggshells. Hens were fed a control diet (CON), the CON diet containing .5 ppm triiodothyronine (T3), the CON diet containing 2.1 ppm iodine as potassium iodide (KI) or the CON diet containing .1% thiouracil (THIO). Feeding T3 decreased plasma thyroxine but elevated plasma T3 concentrations compared to CON. The KI diet had no effect on plasma thyroid hormone concentrations, but feeding THIO depressed plasma thyroxine with no effect on T3, resulting in an elevated ratio of the two hormones compared to the CON ratio. Feeding KI decreased egg volume and T3 increased egg density compared to CON, but no effects on egg weight, surface area, width, or length were noted. Dietary T3 depressed eggshell water vapor conductance compared to CON. Dietary iodine resulted in thinner eggshells with fewer pores than the CON, whereas THIO caused significantly more pores in eggshells than CON but had no effects on shell thickness. Dietary KI had no effects on maternal plasma thyroid hormone concentrations, suggesting that the effects were due to iodine availability rather than to thyroid hormones. It is concluded that the availability of iodine to turkey breeder hens may influence eggshell characteristics.

  4. RNA editing of the GABAA receptor α3 subunit alters the functional properties of recombinant receptors

    OpenAIRE

    Nimmich, Mitchell L.; Heidelberg, Laura S.; Fisher, Janet L.

    2009-01-01

    RNA editing provides a post-transcriptional mechanism to increase structural heterogeneity of gene products. Recently, the α3 subunit of the GABAA receptors has been shown to undergo RNA editing. As a result, a highly conserved isoleucine residue in the third transmembrane domain is replaced with a methionine. To determine the effect of this structural change on receptor function, we compared the GABA sensitivity, pharmacological properties and macroscopic kinetics of recombinant receptors co...

  5. Altered topological properties of functional network connectivity in schizophrenia during resting state: a small-world brain network study.

    Science.gov (United States)

    Yu, Qingbao; Sui, Jing; Rachakonda, Srinivas; He, Hao; Gruner, William; Pearlson, Godfrey; Kiehl, Kent A; Calhoun, Vince D

    2011-01-01

    Aberrant topological properties of small-world human brain networks in patients with schizophrenia (SZ) have been documented in previous neuroimaging studies. Aberrant functional network connectivity (FNC, temporal relationships among independent component time courses) has also been found in SZ by a previous resting state functional magnetic resonance imaging (fMRI) study. However, no study has yet determined if topological properties of FNC are also altered in SZ. In this study, small-world network metrics of FNC during the resting state were examined in both healthy controls (HCs) and SZ subjects. FMRI data were obtained from 19 HCs and 19 SZ. Brain images were decomposed into independent components (ICs) by group independent component analysis (ICA). FNC maps were constructed via a partial correlation analysis of ICA time courses. A set of undirected graphs were built by thresholding the FNC maps and the small-world network metrics of these maps were evaluated. Our results demonstrated significantly altered topological properties of FNC in SZ relative to controls. In addition, topological measures of many ICs involving frontal, parietal, occipital and cerebellar areas were altered in SZ relative to controls. Specifically, topological measures of whole network and specific components in SZ were correlated with scores on the negative symptom scale of the Positive and Negative Symptom Scale (PANSS). These findings suggest that aberrant architecture of small-world brain topology in SZ consists of ICA temporally coherent brain networks.

  6. Antibody to gp41 MPER alters functional properties of HIV-1 Env without complete neutralization.

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    Arthur S Kim

    2014-07-01

    Full Text Available Human antibody 10E8 targets the conserved membrane proximal external region (MPER of envelope glycoprotein (Env subunit gp41 and neutralizes HIV-1 with exceptional potency. Remarkably, HIV-1 containing mutations that reportedly knockout 10E8 binding to linear MPER peptides are partially neutralized by 10E8, producing a local plateau in the dose response curve. Here, we found that virus partially neutralized by 10E8 becomes significantly less neutralization sensitive to various MPER antibodies and to soluble CD4 while becoming significantly more sensitive to antibodies and fusion inhibitors against the heptad repeats of gp41. Thus, 10E8 modulates sensitivity of Env to ligands both pre- and post-receptor engagement without complete neutralization. Partial neutralization by 10E8 was influenced at least in part by perturbing Env glycosylation. With unliganded Env, 10E8 bound with lower apparent affinity and lower subunit occupancy to MPER mutant compared to wild type trimers. However, 10E8 decreased functional stability of wild type Env while it had an opposite, stabilizing effect on MPER mutant Envs. Clade C isolates with natural MPER polymorphisms also showed partial neutralization by 10E8 with altered sensitivity to various gp41-targeted ligands. Our findings suggest a novel mechanism of virus neutralization by demonstrating how antibody binding to the base of a trimeric spike cross talks with adjacent subunits to modulate Env structure and function. The ability of an antibody to stabilize, destabilize, partially neutralize as well as alter neutralization sensitivity of a virion spike pre- and post-receptor engagement may have implications for immunotherapy and vaccine design.

  7. Functional and structural alterations of epithelial barrier properties of rat ileum following X-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Dublineau, I. [Inst. de Radioprotection et de Surete Nucleaire (IRSN), Direction de la RadioProtection de l' Homme, Service de Radiobiologie et d' Epidemiologie, Fontenay-aux-Roses, CEDEX (France)]. E-mail: isabelle.dublineau@irsn.fr; Lebrun, F. [Commissariat a l' Energie Atomique (CEA), Dept. de Radiopathologie et de Radiobiologie, Fontenay-aux-Roses, CEDEX (France); Grison, S.; Griffiths, N.M. [Inst. de Radioprotection et de Surete Nucleaire (IRSN), Direction de la RadioProtection de l' Homme, Service de Radiobiologie et d' Epidemiologie, Fontenay-aux-Roses, CEDEX (France)

    2004-02-01

    Irradiation of the digestive system leads to alterations of the small intestine. We have characterized the disruption of the barrier integrity in rat ileum from 1 to 14 days following irradiation ranging from 6 to 12 Gy. The intestinal permeability to {sup 14}C-mannitol and {sup 3}H-dextran 70,000 was measured in vitro in Ussing chambers. In parallel to these functional studies, immunohistochemical analyses of junctional proteins (ZO-1 and {beta}-catenin) of ileal epithelium were performed by confocal microscopy. Irradiation with 10 Gy induced a marked decrease in epithelial tissue resistance at three days and a fivefold increase in mannitol permeability, without modifications of dextran permeability. A disorganization of the localization for ZO-1 and {beta}-catenin was also observed. At 7 days after irradiation, we observed a recovery of the organization of junctional proteins in parallel to a return of intestinal permeability to control value. In addition to these time-dependent effects, a gradual effect on epithelial integrity of the radiation doses was observed 3 days after irradiation. This study shows a disruption of the integrity of the intestinal barrier in rat ileum following abdominal X-irradiation, depending on the time postirradiation and on the delivered dose. The loss of barrier integrity was characterized by a disorganization of proteins of tight and adherent junctions, leading to increased intestinal permeability to mannitol. (author)

  8. Complement Activation Alters Platelet Function

    Science.gov (United States)

    2015-12-01

    Award Number: W81XWH-12-1-0523 TITLE: Complement Activation Alters Platelet Function PRINCIPAL INVESTIGATOR: George Tsokos, M.D. CONTRACTING...Activation Alters Platelet Function 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-12-1-0523 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) George Tsokos, M.D...a decreased level of disease. Further studies will expand upon these observations better outlining the function of platelets in the injury associated

  9. Properties of Bourbaki's Function

    CERN Document Server

    McCollum, James

    2010-01-01

    We examine Bourbaki's function, an easily-constructed continuous but nowhere-differentiable function, and explore properties including functional identities, the antiderivative, and the Hausdorff dimension of the graph.

  10. Diabetic rat testes: morphological and functional alterations.

    Science.gov (United States)

    Ricci, G; Catizone, A; Esposito, R; Pisanti, F A; Vietri, M T; Galdieri, M

    2009-12-01

    Reproductive dysfunction is a consequence of diabetes, but the underlying mechanisms are poorly understood. This study investigated the histological and molecular alterations in the testes of rats injected with streptozotocin at prepuperal (SPI rats) and adult age (SAI rats) to understand whether diabetes affects testicular tissue with different severity depending on the age in which this pathological condition starts. The testes of diabetic animals showed frequent abnormal histology, and seminiferous epithelium cytoarchitecture appeared altered as well as the occludin distribution pattern. The early occurrence of diabetes increased the percentage of animals with high number of damaged tubules. The interstitial compartment of the testes was clearly hypertrophic in several portions of the organs both in SPI and SAI rats. Interestingly, fully developed Leydig cells were present in all the treated animals although abnormally distributed. Besides the above-described damages, we found a similar decrease in plasma testosterone levels both in SPI and SAI rats. Oxidative stress (OS) is involved in the pathogenesis of various diabetic complications, and in our experimental models we found that manganese superoxide dismutase was reduced in diabetic animals. We conclude that in STZ-induced diabetes, the altered spermatogenesis, more severe in SPI animals, is possibly due to the effect of OS on Leydig cell function which could cause the testosterone decrease responsible for the alterations found in the seminiferous epithelium of diabetic animals.

  11. Radiation induces acute alterations in neuronal function.

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    Peter H Wu

    Full Text Available Every year, nearly 200,000 patients undergo radiation for brain tumors. For both patients and caregivers the most distressing adverse effect is impaired cognition. Efforts to protect against this debilitating effect have suffered from inadequate understanding of the cellular mechanisms of radiation damage. In the past it was accepted that radiation-induced normal tissue injury resulted from a progressive reduction in the survival of clonogenic cells. Moreover, because radiation-induced brain dysfunction is believed to evolve over months to years, most studies have focused on late changes in brain parenchyma. However, clinically, acute changes in cognition are also observed. Because neurons are fully differentiated post-mitotic cells, little information exists on the acute effects of radiation on synaptic function. The purpose of our study was to assess the potential acute effects of radiation on neuronal function utilizing ex vivo hippocampal brain slices. The cellular localization and functional status of excitatory and inhibitory neurotransmitter receptors was identified by immunoblotting. Electrophysiological recordings were obtained both for populations of neuronal cells and individual neurons. In the dentate gyrus region of isolated ex vivo slices, radiation led to early decreases in tyrosine phosphorylation and removal of excitatory N-methyl-D-aspartate receptors (NMDARs from the cell surface while simultaneously increasing the surface expression of inhibitory gamma-aminobutyric acid receptors (GABA(ARs. These alterations in cellular localization corresponded with altered synaptic responses and inhibition of long-term potentiation. The non-competitive NMDAR antagonist memantine blocked these radiation-induced alterations in cellular distribution. These findings demonstrate acute effects of radiation on neuronal cells within isolated brain slices and open new avenues for study.

  12. When "altering brain function" becomes "mind control".

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    Koivuniemi, Andrew; Otto, Kevin

    2014-01-01

    Functional neurosurgery has seen a resurgence of interest in surgical treatments for psychiatric illness. Deep brain stimulation (DBS) technology is the preferred tool in the current wave of clinical experiments because it allows clinicians to directly alter the functions of targeted brain regions, in a reversible manner, with the intent of correcting diseases of the mind, such as depression, addiction, anorexia nervosa, dementia, and obsessive compulsive disorder. These promising treatments raise a critical philosophical and humanitarian question. "Under what conditions does 'altering brain function' qualify as 'mind control'?" In order to answer this question one needs a definition of mind control. To this end, we reviewed the relevant philosophical, ethical, and neurosurgical literature in order to create a set of criteria for what constitutes mind control in the context of DBS. We also outline clinical implications of these criteria. Finally, we demonstrate the relevance of the proposed criteria by focusing especially on serendipitous treatments involving DBS, i.e., cases in which an unintended therapeutic benefit occurred. These cases highlight the importance of gaining the consent of the subject for the new therapy in order to avoid committing an act of mind control.

  13. When Altering Brain Function Becomes Mind Control

    Directory of Open Access Journals (Sweden)

    Andrew Sanford Koivuniemi

    2014-10-01

    Full Text Available Functional neurosurgery has seen a resurgence of interest in surgical treatments for psychiatric illness. Deep brain stimulation (DBS technology is the preferred tool in the current wave of clinical experiments because it allows clinicians to directly alter the functions of targeted brain regions, in a reversible manner, with the intent of correcting diseases of the mind, such as depression, addiction, anorexia nervosa, dementia, and obsessive compulsive disorder. These promising treatments raise a critical philosophical and humanitarian question. Under what conditions does ‘altering brain function’ qualify as ‘mind control’? In order to answer this question one needs a definition of mind control. To this end, we reviewed the relevant philosophical, ethical, and neurosurgical literature in order to create a set of criteria for what constitutes mind control in the context of DBS. We also outline clinical implications of these criteria. Finally, we demonstrate the relevance of the proposed criteria by focusing especially on serendipitous treatments involving DBS, i.e., cases in which an unintended therapeutic benefit occurred. These cases highlight the importance of gaining the consent of the subject for the new therapy in order to avoid committing an act of mind control.

  14. properties and luminosity functions

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    Hektor Monteiro

    2007-01-01

    Full Text Available In this article, we present an investigation of a sample of 1072 stars extracted from the Villanova Catalog of Spectroscopically Identified White Dwarfs (2005 on-line version, studying their distribution in the Galaxy, their physical properties and their luminosity functions. The distances and physical properties of the white dwarfs are determined through interpolation of their (B-V or (b-y colors in model grids. The solar position relative to the Galactic plane, luminosity function, as well as separate functions for each white dwarf spectral type are derived and discussed. We show that the binary fraction does not vary significantly as a function of distance from the Galactic disk out to 100 pc. We propose that the formation rates of DA and non-DAs have changed over time and/or that DAs evolve into non-DA types. The luminosity functions for DAs and DBs have peaks possibly related to a star burst event.

  15. Mitochondrial DNA Alterations and Reduced Mitochondrial Function in Aging

    OpenAIRE

    Hebert, Sadie L.; Lanza, Ian R.; Nair, K. Sreekumaran

    2010-01-01

    Oxidative damage to mitochondrial DNA increases with aging. This damage has the potential to affect mitochondrial DNA replication and transcription which could alter the abundance or functionality of mitochondrial proteins. This review describes mitochondrial DNA alterations and changes in mitochondrial function that occur with aging. Age-related alterations in mitochondrial DNA as a possible contributor to the reduction in mitochondrial function are discussed.

  16. Altered thalamic functional connectivity in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yaou; Liang, Peipeng; Duan, Yunyun; Huang, Jing; Ren, Zhuoqiong; Jia, Xiuqin [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Dong, Huiqing; Ye, Jing [Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Shi, Fu-Dong [Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052 (China); Butzkueven, Helmut [Department of Medicine, University of Melbourne, Parkville 3010 (Australia); Li, Kuncheng, E-mail: kunchengli55@gmail.com [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China)

    2015-04-15

    Highlights: •We demonstrated decreased connectivity between thalamus and cortical regions in MS. •Increased intra- and inter-thalamic connectivity was also observed in MS. •The increased functional connectivity is attenuated by increasing disease duration. -- Abstract: Objective: To compare thalamic functional connectivity (FC) in patients with multiple sclerosis (MS) and healthy controls (HC), and correlate these connectivity measures with other MRI and clinical variables. Methods: We employed resting-state functional MRI (fMRI) to examine changes in thalamic connectivity by comparing thirty-five patients with MS and 35 age- and sex-matched HC. Thalamic FC was investigated by correlating low frequency fMRI signal fluctuations in thalamic voxels with voxels in all other brain regions. Additionally thalamic volume fraction (TF), T2 lesion volume (T2LV), EDSS and disease duration were recorded and correlated with the FC changes. Results: MS patients were found to have a significantly lower TF than HC in bilateral thalami. Compared to HC, the MS group showed significantly decreased FC between thalamus and several brain regions including right middle frontal and parahippocampal gyri, and the left inferior parietal lobule. Increased intra- and inter-thalamic FC was observed in the MS group compared to HC. These FC alterations were not correlated with T2LV, thalamic volume or lesions. In the MS group, however, there was a negative correlation between disease duration and inter-thalamic connectivity (r = −0.59, p < 0.001). Conclusion: We demonstrated decreased FC between thalamus and several cortical regions, while increased intra- and inter-thalamic connectivity in MS patients. These complex functional changes reflect impairments and/or adaptations that are independent of T2LV, thalamic volume or presence of thalamic lesions. The negative correlation between disease duration and inter-thalamic connectivity could indicate an adaptive role of thalamus that is

  17. Altered Functional Connectivity in Essential Tremor

    Science.gov (United States)

    Benito-León, Julián; Louis, Elan D.; Romero, Juan Pablo; Hernández-Tamames, Juan Antonio; Manzanedo, Eva; Álvarez-Linera, Juan; Bermejo-Pareja, Félix; Posada, Ignacio; Rocon, Eduardo

    2015-01-01

    Abstract Essential tremor (ET) has been associated with a spectrum of clinical features, with both motor and nonmotor elements, including cognitive deficits. We employed resting-state functional magnetic resonance imaging (fMRI) to assess whether brain networks that might be involved in the pathogenesis of nonmotor manifestations associated with ET are altered, and the relationship between abnormal connectivity and ET severity and neuropsychological function. Resting-state fMRI data in 23 ET patients (12 women and 11 men) and 22 healthy controls (HC) (12 women and 10 men) were analyzed using independent component analysis, in combination with a “dual-regression” technique, to identify the group differences of resting-state networks (RSNs) (default mode network [DMN] and executive, frontoparietal, sensorimotor, cerebellar, auditory/language, and visual networks). All participants underwent a neuropsychological and neuroimaging session, where resting-state data were collected. Relative to HC, ET patients showed increased connectivity in RSNs involved in cognitive processes (DMN and frontoparietal networks) and decreased connectivity in the cerebellum and visual networks. Changes in network integrity were associated not only with ET severity (DMN) and ET duration (DMN and left frontoparietal network), but also with cognitive ability. Moreover, in at least 3 networks (DMN and frontoparietal networks), increased connectivity was associated with worse performance on different cognitive domains (attention, executive function, visuospatial ability, verbal memory, visual memory, and language) and depressive symptoms. Further, in the visual network, decreased connectivity was associated with worse performance on visuospatial ability. ET was associated with abnormal brain connectivity in major RSNs that might be involved in both motor and nonmotor symptoms. Our findings underscore the importance of examining RSNs in this population as a biomarker of disease. PMID:26656325

  18. Chitosan functional properties.

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    Shepherd, R; Reader, S; Falshaw, A

    1997-06-01

    Chitosan is a partially deacetylated polymer of N-acetyl glucosamine. It is essentially a natural, water-soluble, derivative of cellulose with unique properties. Chitosan is usually prepared from chitin (2 acetamido-2-deoxy beta-1,4-D-glucan) and chitin has been found in a wide range of natural sources (crustaceans, fungi, insects, annelids, molluscs, coelenterata etc.) However chitosan is only manufactured from crustaceans (crab and crayfish) primarily because a large amount of the crustacean exoskeleton is available as a by product of food processing. Squid pens (a waste byproduct of New Zealand squid processing) are a novel, renewable source of chitin and chitosan. Squid pens are currently regarded as waste and so the raw material is relatively cheap. This study was intended to assess the functional properties of squid pen chitosan. Chitosan was extracted from squid pens and assessed for composition, rheology, flocculation, film formation and antimicrobial properties. Crustacean chitosans were also assessed for comparison. Squid chitosan was colourless, had a low ash content and had significantly improved thickening and suspending properties. The flocculation capacity of squid chitosan was low in comparison with the crustacean sourced chitosans. However it should be possible to increase the flocculation capacity of squid pen chitosan by decreasing the degree of acetylation. Films made with squid chitosan were more elastic than crustacean chitosan with improved functional properties. This high quality chitosan could prove particularly suitable for medical/analytical applications.

  19. Functional properties of vinegar.

    Science.gov (United States)

    Budak, Nilgün H; Aykin, Elif; Seydim, Atif C; Greene, Annel K; Guzel-Seydim, Zeynep B

    2014-05-01

    A variety of natural vinegar products are found in civilizations around the world. A review of research on these fermented products indicates numerous reports of health benefits derived by consumption of vinegar components. Therapeutic effects of vinegar arising from consuming the inherent bioactive components including acetic acid, gallic acid, catechin, ephicatechin, chlorogenic acid, caffeic acid, p-coumaric acid, and ferulic acid cause antioxidative, antidiabetic, antimicrobial, antitumor, antiobesity, antihypertensive, and cholesterol-lowering responses. The aims of this article are to discuss vinegar history, production, varieties, acetic acid bacteria, and functional properties of vinegars.

  20. Structure-guided alterations of the gp41-directed HIV-1 broadly neutralizing antibody 2F5 reveal new properties regarding its neutralizing function.

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    Javier Guenaga

    Full Text Available The broadly neutralizing HIV-1 antibody 2F5 recognizes an epitope in the gp41 membrane proximal external region (MPER. The MPER adopts a helical conformation as free peptide, as post-fusogenic forms of gp41, and when bound to the 4E10 monoclonal antibody (Mab. However, when bound to 2F5, the epitope is an extended-loop. The antibody-peptide structure reveals binding between the heavy and light chains with most the long, hydrophobic CDRH3 not contacting peptide. However, mutagenesis identifies this loop as critical for binding, neutralization and for putative hydrophobic membrane interactions. Here, we examined length requirements of the 2F5 CDRH3 and plasticity regarding binding and neutralization. We generated 2F5 variants possessing either longer or shorter CDRH3s and assessed function. The CDRH3 tolerated elongations and reductions up to four residues, displaying a range of binding affinities and retaining some neutralizing capacity. 2F5 antibody variants selective recognition of conformationally distinctive MPER probes suggests a new role for the CDRH3 loop in destabilizing the helical MPER. Binding and neutralization were enhanced by targeted tryptophan substitutions recapitulating fully the activities of the wild-type 2F5 antibody in a shorter CDRH3 variant. MPER alanine scanning revealed binding contacts of this variant downstream of the 2F5 core epitope, into the 4E10 epitope region. This variant displayed increased reactivity to cardiolipin-beta-2-glycoprotein. Tyrosine replacements maintained neutralization while eliminating cardiolipin-beta-2-glycoprotein interaction. The data suggest a new mechanism of action, important for vaccine design, in which the 2F5 CDRH3 contacts and destabilizes the MPER helix downstream of its core epitope to allow induction of the extended-loop conformation.

  1. Some Properties of Bent Functions

    Institute of Scientific and Technical Information of China (English)

    Ying Zhao

    2007-01-01

    First, this paper discusses and sums up some properties of a pair of functions p(x), q(x) that makes (y + 1)p(x) + yq(x) into a bent function. Then it discusses the properties of bent functions. Also, the upper and lower bounds of the number of bent functions on GF(2)2k are discussed.

  2. Dakin Solution Alters Macrophage Viability and Function

    Science.gov (United States)

    2014-07-18

    crobial for wound care. DS has been shown to be toxic to host cells, but effects on immune cells are not well documented. Materials and methods: DS at 0.5...characterize the impact of DS on macrophage viability and function in vitro. 2. Materials and methods 2.1. Cell lines and reagents Murine macrophages...strainer to separate conidia from mycelium , and stored in DMEM at 4C. 2.3. Cellular viability assays Effect of DS on cellular viability was

  3. Alteration of Motor Network Function Following Injury

    Science.gov (United States)

    2013-10-01

    843–852, 1996. Sutherland H, Bickmore WA. Transcription factories: gene expression in unions ? Nat Rev Genet 10: 457–466, 2009. Swensen AM, Marder E...electrodes filled with 3 M KCl (8- to 17-M resistance) with an Axoclamp 2A amplifier (Axon Instru- ments, Union City, CA). In TEVC experiments when all... neuromuscular junction. J Physiol 462: 243–260, 1993. Olson RO, Liu Z, Nomura Y, Song W, Dong K. Molecular and functional characterization of voltage-gated

  4. Altered Functional Performance in Patients with Fibromyalgia

    Science.gov (United States)

    Costa, Isis da Silva; Gamundí, Antoni; Miranda, José G. Vivas; França, Lucas G. Souza; De Santana, Charles Novaes; Montoya, Pedro

    2017-01-01

    Fibromyalgia is a common chronic pain condition that exerts a considerable impact on patients' daily activities and quality of life. Objectives: The main objective of the present study was to evaluate kinematic parameters of gait, functional performance, and balance in women with fibromyalgia syndrome. Methods: The study included 26 female patients with fibromyalgia (49.2 ± 8.0 years) according to the criteria of the American College of Rheumatology, as well as 16 pain-free women (43.5 ± 8.5 years). Gait and balance parameters were extracted from video recordings of participants performing several motor tasks. Non-linear dynamic of body sway time series was also analyzed by computing the Hurst exponent. In addition, functional performance and clinical pain were obtained by using standardized motor tests (Berg's balance scale, 6-min walking test, timed up and go task, Romberg's balance test) and self-report questionnaires (Fibromyalgia Impact Questionnaire). Results: Walking speed was significantly diminished (p balance also revealed significant differences between fibromyalgia and pain-free controls on body sway in the medial-lateral and anterior-posterior axes (all ps balance were significantly associated with high levels of pain, depression, stiffness, anxiety, and fatigue in fibromyalgia. Conclusion: Our data revealed that both gait and balance were severely impaired in FM, and that subjective complaints associated with FM could contribute to functional disability in these patients. These findings suggest that optimal rehabilitation and fall prevention in fibromyalgia require a comprehensive assessment of both psychological responses to pain and physical impairments during postural control and gait. PMID:28184193

  5. Spaceflight alters immune cell function and distribution

    Science.gov (United States)

    Sonnenfeld, Gerald; Mandel, Adrian D.; Konstantinova, Irina V.; Berry, Wallace D.; Taylor, Gerald R.; Lesniak, A. T.; Fuchs, Boris B.; Rakhmilevich, Alexander L.

    1992-01-01

    Experiments are described which were performed onboard Cosmos 2044 to determine spaceflight effects on immunologically important cell function and distribution. Results indicate that bone marrow cells from flown and suspended rats exhibited a decreased response to a granulocyte/monocyte colony-stimulating factor compared with the bone marrow cells from control rats. Bone marrow cells showed an increase in the percentage of cells expressing markers for helper T-cells in the myelogenous population and increased percentages of anti-asialo granulocyte/monocyte-1-bearing interleulin-2 receptor bearing pan T- and helper T-cells in the lymphocytic population.

  6. Oxidative stress alters physiological and morphological neuronal properties.

    Science.gov (United States)

    Hasan, Sonia M; Joe, Mary; Alshuaib, Waleed B

    2007-07-01

    We investigated the effects of H(2)O(2)-induced oxidative stress on the delayed-rectifier current (IK(DR)), neuronal physiological and morphological properties. Measurements were obtained from hippocampal CA1 neurons in control solution and from the same neurons after exposure to oxidative stress (short- and long-term H(2)O(2) external applications at 0.1, 1, and 10 mM). With short-term (6 min) H(2)O(2) (1 mM) treatment, IK(DR) measured in the H(2)O(2)-containing solution (778 +/- 23 pA, n=20), was smaller than that measured in the control Ca(2+)-free Hepes solution (1,112 +/- 38 pA, n=20). Coenzyme Q(10) (0.1 mM) pretreatment prevented the H(2)O(2)-induced inhibition of IK(DR). With long-term (40, 80 min) H(2)O(2) (0.1, 10 mM) treatment, the neuron lost its distinctive shape (rounded up) and the neurite almost disappeared. These results suggest that oxidative stress, which inhibits IK(DR), can alter neural activity. The morphological changes caused by H(2)O(2) support the idea that oxidative stress causes intracellular damage and compromises neural function.

  7. Chromophore Deprotonation State Alters the Optical Properties of Blue Chromoprotein.

    Directory of Open Access Journals (Sweden)

    Cheng-Yi Chiang

    Full Text Available Chromoproteins (CPs have unique colors and can be used in biological applications. In this work, a novel blue CP with a maximum absorption peak (λmax at 608 nm was identified from the carpet anemone Stichodactyla gigantea (sgBP. In vivo expression of sgBP in zebrafish would change the appearance of the fishes to have a blue color, indicating the potential biomarker function. To enhance the color properties, the crystal structure of sgBP at 2.25 Å resolution was determined to allow structure-based protein engineering. Among the mutations conducted in the Gln-Tyr-Gly chromophore and chromophore environment, a S157C mutation shifted the λmax to 604 nm with an extinction coefficient (ε of 58,029 M-1·cm-1 and darkened the blue color expression. The S157C mutation in the sgBP chromophore environment could affect the color expression by altering the deprotonation state of the phenolic group in the chromophore. Our results provide a structural basis for the blue color enhancement of the biomarker development.

  8. Evidence for Alteration in Chemical and Physical Properties of Water and Modulation of its Biological Functions by Sunlight Transmitted through Color Ranges of the Visible Spectrum-A Novel Study

    Directory of Open Access Journals (Sweden)

    M. Rajeswara Rao

    2005-08-01

    Full Text Available We investigated the changes in the properties of water when exposed to sunlight for 40 days. We hypothesize and prove that solar irradiation to water entraps electromagnetic radiation as potential energy, which becomes kinetic energy in various systems. It is postulated that photochemically-induced energy transfers, associated with individual spectral emission of visible spectrum of solar light, exert diverse influences on biological systems. Bottles of distilled water, individually wrapped in spectral-colored cellophane were exposed to sunlight and compared to an unwrapped bottle to determine chemical and physical changes as well as modifications of biological properties. Each bottle of water was named according to the color of cellophane paper with letter E (stands for exposed as a prefix with (E-violet, E-indigo, E-blue, E-green, E-yellow, E-orange, and Ered. E-control (without wrap was exposed to polychromatic sunlight. This study addresses two main issues viz., the chemical and physical changes in E-water and its effect on biological activities. Chemical and physical composition analysis using inductively coupled plasma atomic emission spectrometry; physical conductance by a Wheatstone Bridge type conductivity meter; osmolarity by a vapor pressure osmometer; and, salt solubility profile of 10% sodium bicarbonate were determined. Furthermore, testing the effect of E-waters on human lymphocyte proliferation, mosquito larvae hatching and seed germination determined the functional role of solar radiation through specific spectrum/s of visible light on various biological processes. We found that water exposed to visible spectral emissions of sunlight had an altered elemental composition, electrical conductance, osmolarity and salt-solubility, as well as differences in bio-modulatory effects. A gradual increase in leaching of Boron from Eviolet to E-red was noted. E-indigo showed maximal increase in electrical conductance and maximal salt

  9. Altered functional and structural connectivity networks in psychogenic non-epileptic seizures.

    Directory of Open Access Journals (Sweden)

    Ju-Rong Ding

    Full Text Available Psychogenic non-epileptic seizures (PNES are paroxysmal behaviors that resemble epileptic seizures but lack abnormal electrical activity. Recent studies suggest aberrant functional connectivity involving specific brain regions in PNES. Little is known, however, about alterations of topological organization of whole-brain functional and structural connectivity networks in PNES. We constructed functional connectivity networks from resting-state functional MRI signal correlations and structural connectivity networks from diffusion tensor imaging tractography in 17 PNES patients and 20 healthy controls. Graph theoretical analysis was employed to compute network properties. Moreover, we investigated the relationship between functional and structural connectivity networks. We found that PNES patients exhibited altered small-worldness in both functional and structural networks and shifted towards a more regular (lattice-like organization, which could serve as a potential imaging biomarker for PNES. In addition, many regional characteristics were altered in structural connectivity network, involving attention, sensorimotor, subcortical and default-mode networks. These regions with altered nodal characteristics likely reflect disease-specific pathophysiology in PNES. Importantly, the coupling strength of functional-structural connectivity was decreased and exhibited high sensitivity and specificity to differentiate PNES patients from healthy controls, suggesting that the decoupling strength of functional-structural connectivity might be an important characteristic reflecting the mechanisms of PNES. This is the first study to explore the altered topological organization in PNES combining functional and structural connectivity networks, providing a new way to understand the pathophysiological mechanisms of PNES.

  10. Altered functional connectivity of prefrontal cortex in chronic heroin abusers

    Institute of Scientific and Technical Information of China (English)

    Yinbao Qi; Xianming Fu; Ruobing Qian; Chaoshi Niu; Xiangpin Wei

    2011-01-01

    In this study, we investigated alterations in the resting-state functional connectivity of the pre-frontal cortex in chronic heroin abusers using functional magnetic resonance imaging. We found that, compared with normal controls, in heroin abusers the left prefrontal cortex showed decreased functional connectivity with the left hippocampus, right anterior cingulate, left middle frontal gyrus, right middle frontal gyrus and right precuneus. However, the right prefrontal cortex showed decreased functional connectivity with the left orbital frontal cortex and the left middle frontal gyrus in chronic heroin abusers. These alterations of resting-state functional connectivity in the prefrontal cortices of heroin abusers suggest that their frontal executive neural network may be impaired, and that this may contribute to their continued heroin abuse and relapse after withdrawal.

  11. Altered default mode network functional connectivity in schizotypal personality disorder.

    Science.gov (United States)

    Zhang, Qing; Shen, Jing; Wu, Jianlin; Yu, Xiao; Lou, Wutao; Fan, Hongyu; Shi, Lin; Wang, Defeng

    2014-12-01

    The default mode network (DMN) has been identified to play a critical role in many mental disorders, but such abnormalities have not yet been determined in patients with schizotypal personality disorder (SPD). The purpose of this study was to analyze the alteration of the DMN functional connectivity in subjects with (SPD) and compared it to healthy control subjects. Eighteen DSM-IV diagnosed SPD subjects (all male, average age: 19.7±0.9) from a pool of 3000 first year college students, and eighteen age and gender matched healthy control subjects were recruited (all male, average age: 20.3±0.9). Independent component analysis (ICA) was used to analyze the DMN functional connectivity alteration. Compared to the healthy control group, SPD subjects had significantly decreased functional connectivity in the frontal areas, including the superior and medial frontal gyrus, and greater functional connectivity in the bilateral superior temporal gyrus and sub-lobar regions, including the bilateral putamen and caudate. Compared to subjects with SPD, the healthy control group showed decreased functional connectivity in the bilateral posterior cingulate gyrus, but showed greater functional connectivity in the right transverse temporal gyrus and left middle temporal gyrus. The healthy control group also showed greater activation in the cerebellum compared to the SPD group. These findings suggest that DMN functional connectivity, particularly that involving cognitive or emotional regulation, is altered in SPD subjects, and thus may be helpful in studying schizophrenia.

  12. Phytochemicals Perturb Membranes and Promiscuously Alter Protein Function

    NARCIS (Netherlands)

    Ingólfsson, Helgi I; Thakur, Pratima; Herold, Karl F; Hobart, E Ashley; Ramsey, Nicole B; Periole, Xavier; de Jong, Djurre H; Zwama, Martijn; Yilmaz, Duygu; Hall, Katherine; Maretzky, Thorsten; Hemmings, Hugh C; Blobel, Carl; Marrink, Siewert J; Kocer, Armagan; Sack, Jon T; Andersen, Olaf S

    2014-01-01

    A wide variety of phytochemicals are consumed for their perceived health benefits. Many of these phytochemicals have been found to alter numerous cell functions, but the mechanisms underlying their biological activity tend to be poorly understood. Phenolic phytochemicals are particularly promiscuous

  13. Connectomics and neuroticism : an altered functional network organization

    NARCIS (Netherlands)

    Servaas, Michelle N; Geerligs, Linda; Renken, Remco J; Marsman, Jan-Bernard; Ormel, Johan; Riese, Harriëtte; Aleman, André

    2015-01-01

    The personality trait neuroticism is a potent risk marker for psychopathology. Although the neurobiological basis remains unclear, studies have suggested that alterations in connectivity may underlie it. Therefore, the aim of the current study was to shed more light on the functional network organiz

  14. Extinction order and altered community structure rapidly disrupt ecosystem functioning.

    Science.gov (United States)

    Larsen, Trond H; Williams, Neal M; Kremen, Claire

    2005-05-01

    By causing extinctions and altering community structure, anthropogenic disturbances can disrupt processes that maintain ecosystem integrity. However, the relationship between community structure and ecosystem functioning in natural systems is poorly understood. Here we show that habitat loss appeared to disrupt ecosystem functioning by affecting extinction order, species richness and abundance. We studied pollination by bees in a mosaic of agricultural and natural habitats in California and dung burial by dung beetles on recently created islands in Venezuela. We found that large-bodied bee and beetle species tended to be both most extinction-prone and most functionally efficient, contributing to rapid functional loss. Simulations confirmed that extinction order led to greater disruption of function than predicted by random species loss. Total abundance declined with richness and also appeared to contribute to loss of function. We demonstrate conceptually and empirically how the non-random response of communities to disturbance can have unexpectedly large functional consequences.

  15. Muscle fatigue in frog semitendinosus: alterations in contractile function

    Science.gov (United States)

    Thompson, L. V.; Balog, E. M.; Riley, D. A.; Fitts, R. H.

    1992-01-01

    The purpose of this study was to characterize the contractile properties of the frog semitendinosus (ST) muscle before and during recovery from fatigue, to relate the observed functional changes to alterations in specific steps in the crossbridge model of muscle contraction, and to determine how fatigue affects the force-frequency relationship. The frog ST (22 degrees C) was fatigued by direct electrical stimulation with 100-ms 150-Hz trains at 1/s for 5 min. The fatigue protocol reduced peak twitch (Pt) and tetanic (Po) force to 32 and 8.5% of initial force, respectively. The decline in Pt was less than Po, in part due to a prolongation in the isometric contraction time (CT), which increased to 300% of the initial value. The isometric twitch duration was greatly prolonged as reflected by the lengthened CT and the 800% increase in the one-half relaxation time (1/2RT). Both Pt and Po showed a biphasic recovery, a rapid initial phase (2 min) followed by a slower (40 min) return to the prefatigue force. CT and 1/2RT also recovered in two phases, returning to 160 and 265% of control in the first 5 min. CT returned to the prefatigue value between 35 and 40 min, whereas even at 60 min 1/2RT was 133% of control. The maximal velocity of shortening, determined by the slack test, was significantly reduced [from 6.7 +/- 0.5 to 2.5 +/- 0.4 optimal muscle length/s] at fatigue. The force-frequency relationship was shifted to the left, so that optimal frequency for generating Po was reduced.(ABSTRACT TRUNCATED AT 250 WORDS).

  16. Prenatal stress alters amygdala functional connectivity in preterm neonates.

    Science.gov (United States)

    Scheinost, Dustin; Kwon, Soo Hyun; Lacadie, Cheryl; Sze, Gordon; Sinha, Rajita; Constable, R Todd; Ment, Laura R

    2016-01-01

    Exposure to prenatal and early-life stress results in alterations in neural connectivity and an increased risk for neuropsychiatric disorders. In particular, alterations in amygdala connectivity have emerged as a common effect across several recent studies. However, the impact of prenatal stress exposure on the functional organization of the amygdala has yet to be explored in the prematurely-born, a population at high risk for neuropsychiatric disorders. We test the hypothesis that preterm birth and prenatal exposure to maternal stress alter functional connectivity of the amygdala using two independent cohorts. The first cohort is used to establish the effects of preterm birth and consists of 12 very preterm neonates and 25 term controls, all without prenatal stress exposure. The second is analyzed to establish the effects of prenatal stress exposure and consists of 16 extremely preterm neonates with prenatal stress exposure and 10 extremely preterm neonates with no known prenatal stress exposure. Standard resting-state functional magnetic resonance imaging and seed connectivity methods are used. When compared to term controls, very preterm neonates show significantly reduced connectivity between the amygdala and the thalamus, the hypothalamus, the brainstem, and the insula (p cortex (p subcortical regions is decreased in preterm neonates compared to term controls. In addition, these data, for the first time, suggest that prenatal stress exposure amplifies these decreases.

  17. Altered cross-bridge properties in skeletal muscle dystrophies

    Science.gov (United States)

    Guellich, Aziz; Negroni, Elisa; Decostre, Valérie; Demoule, Alexandre; Coirault, Catherine

    2014-01-01

    Force and motion generated by skeletal muscle ultimately depends on the cyclical interaction of actin with myosin. This mechanical process is regulated by intracellular Ca2+ through the thin filament-associated regulatory proteins i.e.; troponins and tropomyosin. Muscular dystrophies are a group of heterogeneous genetic affections characterized by progressive degeneration and weakness of the skeletal muscle as a consequence of loss of muscle tissue which directly reduces the number of potential myosin cross-bridges involved in force production. Mutations in genes responsible for skeletal muscle dystrophies (MDs) have been shown to modify the function of contractile proteins and cross-bridge interactions. Altered gene expression or RNA splicing or post-translational modifications of contractile proteins such as those related to oxidative stress, may affect cross-bridge function by modifying key proteins of the excitation-contraction coupling. Micro-architectural change in myofilament is another mechanism of altered cross-bridge performance. In this review, we provide an overview about changes in cross-bridge performance in skeletal MDs and discuss their ultimate impacts on striated muscle function. PMID:25352808

  18. Altered cross-bridge properties in skeletal muscle dystrophies.

    Science.gov (United States)

    Guellich, Aziz; Negroni, Elisa; Decostre, Valérie; Demoule, Alexandre; Coirault, Catherine

    2014-01-01

    Force and motion generated by skeletal muscle ultimately depends on the cyclical interaction of actin with myosin. This mechanical process is regulated by intracellular Ca(2+) through the thin filament-associated regulatory proteins i.e.; troponins and tropomyosin. Muscular dystrophies are a group of heterogeneous genetic affections characterized by progressive degeneration and weakness of the skeletal muscle as a consequence of loss of muscle tissue which directly reduces the number of potential myosin cross-bridges involved in force production. Mutations in genes responsible for skeletal muscle dystrophies (MDs) have been shown to modify the function of contractile proteins and cross-bridge interactions. Altered gene expression or RNA splicing or post-translational modifications of contractile proteins such as those related to oxidative stress, may affect cross-bridge function by modifying key proteins of the excitation-contraction coupling. Micro-architectural change in myofilament is another mechanism of altered cross-bridge performance. In this review, we provide an overview about changes in cross-bridge performance in skeletal MDs and discuss their ultimate impacts on striated muscle function.

  19. Altered cross-bridge properties in skeletal muscle dystrophies

    Directory of Open Access Journals (Sweden)

    Aziz eGuellich

    2014-10-01

    Full Text Available Force and motion generated by skeletal muscle ultimately depends on the cyclical interaction of actin with myosin. This mechanical process is regulated by intracellular Ca2+ through the thin filament-associated regulatory proteins i.e.; troponins and tropomyosin. Muscular dystrophies are a group of heterogeneous genetic affections characterized by progressive degeneration and weakness of the skeletal muscle as a consequence of loss of muscle tissue which directly reduces the number of potential myosin cross-bridges involved in force production. Mutations in genes responsible for skeletal muscle dystrophies have been shown to modify the function of contractile proteins and cross-bridge interactions. Altered gene expression or RNA splicing or post-translational modifications of contractile proteins such as those related to oxidative stress, may affect cross-bridge function by modifying key proteins of the excitation-contraction coupling. Micro-architectural change in myofilament is another mechanism of altered cross-bridge performance. In this review, we provide an overview about changes in cross-bridge performance in skeletal muscle dystrophies and discuss their ultimate impacts on striated muscle function.

  20. Amphotericin B nephrotoxicity: the adverse consequences of altered membrane properties.

    Science.gov (United States)

    Sawaya, B P; Briggs, J P; Schnermann, J

    1995-08-01

    Amphotericin B (AmB) has been in clinical use for more than 30 yr but has remained the most effective drug for treatment of serious fungal infections. Its use has increased in recent years, as the result of increases in aggressive intensive care support and increased numbers of immunocompromised patients. Nephrotoxic manifestations are common, and this is the major factor limiting the clinical use of the drug. A number of recent studies have contributed to a better understanding of the mechanism by which AmB exerts its nephrotoxic effect. AmB alters cell membrane permeability and probably as a consequence alters tubular and vascular smooth muscle cell function, leading to various tubular transport defects and vasoconstriction. Decreased RBF appears to play a major role in AmB-induced reduction GFR, and recurrent ischemia may be the basis of permanent structural nephrotoxic effects. Salt loading is the only measure proven by controlled prospective study to ameliorate AmB nephrotoxicity in humans. Liposomal AmB and the formulation of an emulsion of AmB in lipid may provide a protective effect based on altering the affinity of AmB for mammalian cell membranes, while preserving high efficacy against fungal cells. However, further studies are needed to evaluate the efficacy and safety of these new AmB formulations.

  1. Altered plasma fibrin clot properties in essential thrombocythemia.

    Science.gov (United States)

    Małecki, Rafał; Gacka, Małgorzata; Kuliszkiewicz-Janus, Małgorzata; Jakobsche-Policht, Urszula; Kwiatkowski, Jacek; Adamiec, Rajmund; Undas, Anetta

    2016-01-01

    Patients with increased thromboembolic risk tend to form denser fibrin clots which are relatively resistant to lysis. We sought to investigate whether essential thrombocythemia (ET) is associated with altered fibrin clot properties in plasma. Ex vivo plasma fibrin clot permeability coefficient (Ks), turbidimetry and clot lysis time (CLT) were measured in 43 consecutive patients with ET (platelet count from 245 to 991 × 10(3)/µL) and 50 control subjects matched for age, sex and comorbidities. Fibrinolysis proteins and inhibitors together with platelet activation markers were determined. Reduced Ks (-38%, p Ks inversely correlated with fibrinogen, PF4 and C-reactive protein. CLT positively correlated only with PAI-1. Patients with ET display prothrombotic plasma fibrin clot phenotype including impaired fibrinolysis, which represents a new prothrombotic mechanism in this disease.

  2. Connectomics and neuroticism: an altered functional network organization.

    Science.gov (United States)

    Servaas, Michelle N; Geerligs, Linda; Renken, Remco J; Marsman, Jan-Bernard C; Ormel, Johan; Riese, Harriëtte; Aleman, André

    2015-01-01

    The personality trait neuroticism is a potent risk marker for psychopathology. Although the neurobiological basis remains unclear, studies have suggested that alterations in connectivity may underlie it. Therefore, the aim of the current study was to shed more light on the functional network organization in neuroticism. To this end, we applied graph theory on resting-state functional magnetic resonance imaging (fMRI) data in 120 women selected based on their neuroticism score. Binary and weighted brain-wide graphs were constructed to examine changes in the functional network structure and functional connectivity strength. Furthermore, graphs were partitioned into modules to specifically investigate connectivity within and between functional subnetworks related to emotion processing and cognitive control. Subsequently, complex network measures (ie, efficiency and modularity) were calculated on the brain-wide graphs and modules, and correlated with neuroticism scores. Compared with low neurotic individuals, high neurotic individuals exhibited a whole-brain network structure resembling more that of a random network and had overall weaker functional connections. Furthermore, in these high neurotic individuals, functional subnetworks could be delineated less clearly and the majority of these subnetworks showed lower efficiency, while the affective subnetwork showed higher efficiency. In addition, the cingulo-operculum subnetwork demonstrated more ties with other functional subnetworks in association with neuroticism. In conclusion, the 'neurotic brain' has a less than optimal functional network organization and shows signs of functional disconnectivity. Moreover, in high compared with low neurotic individuals, emotion and salience subnetworks have a more prominent role in the information exchange, while sensory(-motor) and cognitive control subnetworks have a less prominent role.

  3. Elevation alters ecosystem properties across temperate treelines globally

    Science.gov (United States)

    Mayor, Jordan R.; Sanders, Nathan J.; Classen, Aimée T.; Bardgett, Richard D.; Clément, Jean-Christophe; Fajardo, Alex; Lavorel, Sandra; Sundqvist, Maja K.; Bahn, Michael; Chisholm, Chelsea; Cieraad, Ellen; Gedalof, Ze’Ev; Grigulis, Karl; Kudo, Gaku; Oberski, Daniel L.; Wardle, David A.

    2017-01-01

    Temperature is a primary driver of the distribution of biodiversity as well as of ecosystem boundaries. Declining temperature with increasing elevation in montane systems has long been recognized as a major factor shaping plant community biodiversity, metabolic processes, and ecosystem dynamics. Elevational gradients, as thermoclines, also enable prediction of long-term ecological responses to climate warming. One of the most striking manifestations of increasing elevation is the abrupt transitions from forest to treeless alpine tundra. However, whether there are globally consistent above- and belowground responses to these transitions remains an open question. To disentangle the direct and indirect effects of temperature on ecosystem properties, here we evaluate replicate treeline ecotones in seven temperate regions of the world. We find that declining temperatures with increasing elevation did not affect tree leaf nutrient concentrations, but did reduce ground-layer community-weighted plant nitrogen, leading to the strong stoichiometric convergence of ground-layer plant community nitrogen to phosphorus ratios across all regions. Further, elevation-driven changes in plant nutrients were associated with changes in soil organic matter content and quality (carbon to nitrogen ratios) and microbial properties. Combined, our identification of direct and indirect temperature controls over plant communities and soil properties in seven contrasting regions suggests that future warming may disrupt the functional properties of montane ecosystems, particularly where plant community reorganization outpaces treeline advance.

  4. Altered functional brain networks in Prader-Willi syndrome.

    Science.gov (United States)

    Zhang, Yi; Zhao, Heng; Qiu, Siyou; Tian, Jie; Wen, Xiaotong; Miller, Jennifer L; von Deneen, Karen M; Zhou, Zhenyu; Gold, Mark S; Liu, Yijun

    2013-06-01

    Prader-Willi syndrome (PWS) is a genetic imprinting disorder characterized mainly by hyperphagia and early childhood obesity. Previous functional neuroimaging studies used visual stimuli to examine abnormal activities in the eating-related neural circuitry of patients with PWS. It was found that patients with PWS exhibited both excessive hunger and hyperphagia consistently, even in situations without any food stimulation. In the present study, we employed resting-state functional MRI techniques to investigate abnormal brain networks related to eating disorders in children with PWS. First, we applied amplitude of low-frequency fluctuation analysis to define the regions of interest that showed significant alterations in resting-state brain activity levels in patients compared with their sibling control group. We then applied a functional connectivity (FC) analysis to these regions of interest in order to characterize interactions among the brain regions. Our results demonstrated that patients with PWS showed decreased FC strength in the medial prefrontal cortex (MPFC)/inferior parietal lobe (IPL), MPFC/precuneus, IPL/precuneus and IPL/hippocampus in the default mode network; decreased FC strength in the pre-/postcentral gyri and dorsolateral prefrontal cortex (DLPFC)/orbitofrontal cortex (OFC) in the motor sensory network and prefrontal cortex network, respectively; and increased FC strength in the anterior cingulate cortex/insula, ventrolateral prefrontal cortex (VLPFC)/OFC and DLPFC/VLPFC in the core network and prefrontal cortex network, respectively. These findings indicate that there are FC alterations among the brain regions implicated in eating as well as rewarding, even during the resting state, which may provide further evidence supporting the use of PWS as a model to study obesity and to provide information on potential neural targets for the medical treatment of overeating.

  5. Implication of altered proteasome function in alcoholic liver injury

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The proteasome is a major protein-degrading enzyme,which catalyzes degradation of oxidized and aged proteins, signal transduction factors and cleaves peptides for antigen presentation. Proteasome exists in the equilibrium of 26S and 20S particles. Proteasome function is altered by ethanol metabolism, depending on oxidative stress levels: low oxidative stress induces proteasome activity, while high oxidative stress reduces it. The proposed mechanisms for modulation of proteasome activity are related to oxidative modification of proteasomal proteins with primary and secondary products derived from ethanol oxidation.Decreased proteolysis by the proteasome results in the accumulation of insoluble protein aggregates, which cannot be degraded by proteasome and which further inhibit proteasome function. Mallory bodies, a common signature of alcoholic liver diseases, are formed by liver cells, when proteasome is unable to remove cytokeratins.Proteasome inhibition by ethanol also promotes the accumulation of pro-apoptotic factors in mitochondria of ethanol-metabolizing liver cells that are normally degraded by proteasome. In addition, decreased proteasome function also induces accumulation of the negative regulators of cytokine signaling (Ⅰ-κB and SOCS), thereby blocking cytokine signal transduction.Finally, ethanol-elicited blockade of interferon type 1 and 2 signaling and decreased proteasome function impairs generation of peptides for MHC class Ⅰ-restricted antigen presentation.

  6. Effects of Chemotherapy-Induced Alterations in Cell Mechanical Properties on Cancer Metastasis

    Science.gov (United States)

    Prathivadhi, Sruti; Ekpenyong, Andrew; Nichols, Michael; Taylor, Carolyn; Ning, Jianhao

    Biological cells can modulate their mechanical properties to suit their functions and in response to changes in their environment. Thus, mechanical phenotyping of cells has been employed for tracking stem cell differentiation, bacterial infection, cell death, etc. Malignant transformation of cells also involves changes in mechanical properties. However, the extent to which mechanical properties of cancer cells contribute to metastasis is not well understood. Yet, more than 90% of all cancer deaths are directly related to metastasis. Transit of cells through the microcirculation is one of the key features of metastasis. We hypothesize that cancer treatment regimens do inadvertently alter cell mechanical properties in ways that might promote cancer metastasis. We use a microfluidic microcirculation mimetic (MMM) platform which mimics the capillary constrictions of the pulmonary and peripheral microcirculation to determine if in-vivo-like mechanical stimuli can evoke different responses from cells subjected to various cancer drugs. In particular, we show that cancer cells treated with chemotherapeutic drugs such as daunorubicin, become more deformable at short timescales (0.1 s) and transit faster through the device. Our results are first steps in evaluating the pro- or anti-metastatic effects of chemotherapeutic drugs based on their induced alterations in cell mechanical properties.

  7. Alterations in cognitive and psychological functioning after organic solvent exposure

    Energy Technology Data Exchange (ETDEWEB)

    Morrow, L.A.; Ryan, C.M.; Hodgson, M.J.; Robin, N. (Univ. of Pittsburgh School of Medicine, PA (USA))

    1990-05-01

    Exposure to organic solvents has been linked repeatedly to alterations in both personality and cognitive functioning. To assess the nature and extent of these changes more thoroughly, 32 workers with a history of exposure to mixtures of organic solvents and 32 age- and education-matched blue-collar workers with no history of exposure were assessed with a comprehensive battery of neuropsychological tests. Although both groups were comparable on measures of general intelligence, significant differences were found in virtually all other cognitive domains tested (Learning and Memory, Visuospatial, Attention and Mental Flexibility, Psychomotor Speed). In addition, Minnesota Multiphasic Personality Inventories of exposed workers indicated clinically significant levels of depression, anxiety, somatic concerns and disturbances in thinking. The reported psychological distress was unrelated to degree of cognitive deficit. Finally, several exposure-related variables were associated with poorer performance on tests of memory and visuospatial ability.

  8. 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.

  9. Alteration of Skin Properties with Autologous Dermal Fibroblasts

    Directory of Open Access Journals (Sweden)

    Rajesh L. Thangapazham

    2014-05-01

    Full Text Available Dermal fibroblasts are mesenchymal cells found between the skin epidermis and subcutaneous tissue. They are primarily responsible for synthesizing collagen and glycosaminoglycans; components of extracellular matrix supporting the structural integrity of the skin. Dermal fibroblasts play a pivotal role in cutaneous wound healing and skin repair. Preclinical studies suggest wider applications of dermal fibroblasts ranging from skin based indications to non-skin tissue regeneration in tendon repair. One clinical application for autologous dermal fibroblasts has been approved by the Food and Drug Administration (FDA while others are in preclinical development or various stages of regulatory approval. In this context, we outline the role of fibroblasts in wound healing and discuss recent advances and the current development pipeline for cellular therapies using autologous dermal fibroblasts. The microanatomic and phenotypic differences of fibroblasts occupying particular locations within the skin are reviewed, emphasizing the therapeutic relevance of attributes exhibited by subpopulations of fibroblasts. Special focus is provided to fibroblast characteristics that define regional differences in skin, including the thick and hairless skin of the palms and soles as compared to hair-bearing skin. This regional specificity and functional identity of fibroblasts provides another platform for developing regional skin applications such as the induction of hair follicles in bald scalp or alteration of the phenotype of stump skin in amputees to better support their prosthetic devices.

  10. How linear features alter predator movement and the functional response.

    KAUST Repository

    McKenzie, Hannah W

    2012-01-18

    In areas of oil and gas exploration, seismic lines have been reported to alter the movement patterns of wolves (Canis lupus). We developed a mechanistic first passage time model, based on an anisotropic elliptic partial differential equation, and used this to explore how wolf movement responses to seismic lines influence the encounter rate of the wolves with their prey. The model was parametrized using 5 min GPS location data. These data showed that wolves travelled faster on seismic lines and had a higher probability of staying on a seismic line once they were on it. We simulated wolf movement on a range of seismic line densities and drew implications for the rate of predator-prey interactions as described by the functional response. The functional response exhibited a more than linear increase with respect to prey density (type III) as well as interactions with seismic line density. Encounter rates were significantly higher in landscapes with high seismic line density and were most pronounced at low prey densities. This suggests that prey at low population densities are at higher risk in environments with a high seismic line density unless they learn to avoid them.

  11. On Properties of Geodesic -Preinvex Functions

    Directory of Open Access Journals (Sweden)

    I. Ahmad

    2009-01-01

    Full Text Available The present paper deals with the properties of geodesic -preinvex functions and their relationships with -invex functions and strictly geodesic -preinvex functions. The geodesic -pre-pseudo-invex and geodesic -pre-quasi-invex functions on the geodesic invex set are introduced and some of their properties are discussed.

  12. Changes in cognitive state alter human functional brain networks

    Directory of Open Access Journals (Sweden)

    Malaak Nasser Moussa

    2011-08-01

    Full Text Available The study of the brain as a whole system can be accomplished using network theory principles. Research has shown that human functional brain networks during a resting state exhibit small-world properties and high degree nodes, or hubs, localized to brain areas consistent with the default mode network (DMN. However, the study of brain networks across different tasks and or cognitive states has been inconclusive. Research in this field is important because the underpinnings of behavioral output are inherently dependent on whether or not brain networks are dynamic. This is the first comprehensive study to evaluate multiple network metrics at a voxel-wise resolution in the human brain at both the whole brain and regional level under various conditions: resting state, visual stimulation, and multisensory (auditory and visual stimulation. Our results show that despite global network stability, functional brain networks exhibit considerable task-induced changes in connectivity, efficiency, and community structure at the regional level.

  13. PROPERTIES OF THE CONVOLUTION WITH PRESTARLIKE FUNCTIONS

    Institute of Scientific and Technical Information of China (English)

    Jacek DZIOK

    2013-01-01

    In the paper we investigate convolution properties related to the prestarlike functions and various inclusion relationships between defined classes of functions. Interest-ing applications involving the well-known classes of functions defined by linear operators are also considered.

  14. Alterations of blood brain barrier function in hyperammonemia: an overview.

    Science.gov (United States)

    Skowrońska, Marta; Albrecht, Jan

    2012-02-01

    Ammonia is a neurotoxin involved in the pathogenesis of neurological conditions associated with hyperammonemia, including hepatic encephalopathy, a condition associated with acute--(ALF) or chronic liver failure. This article reviews evidence that apart from directly affecting the metabolism and function of the central nervous system cells, ammonia influences the passage of different molecules across the blood brain barrier (BBB). A brief description is provided of the tight junctions, which couple adjacent cerebral capillary endothelial cells to each other to form the barrier. Ammonia modulates the transcellular passage of low-to medium-size molecules, by affecting their carriers located at the BBB. Ammonia induces interrelated aberrations of the transport of the large neutral amino acids and aromatic amino acids (AAA), whose influx is augmented by exchange with glutamine produced in the course of ammonia detoxification, and maybe also modulated by the extracellularly acting gamma-glutamyl moiety transferring enzyme, gamma-glutamyl-transpeptidase. Impaired AAA transport affects neurotransmission by altering intracerebral synthesis of catecholamines (serotonin and dopamine), and producing "false neurotransmitters" (octopamine and phenylethylamine). Ammonia also modulates BBB transport of the cationic amino acids: the nitric oxide precursor, arginine, and ornithine, which is an ammonia trap, and affects the transport of energy metabolites glucose and creatine. Moreover, ammonia acting either directly or in synergy with liver injury-derived inflammatory cytokines also evokes subtle increases of the transcellular passage of molecules of different size (BBB "leakage"), which appears to be responsible for the vasogenic component of cerebral edema associated with ALF.

  15. Uniqueness property for quasiharmonic functions

    Directory of Open Access Journals (Sweden)

    Sevdiyor A. Imomkulov

    2014-10-01

    Full Text Available In this paper we consider a class of continuous functions, called quasiaharmonic functions, admitting best approximations by harmonic polynomials. In this class we prove a uniqueness theorem by analogy with the analytic functions.

  16. Allosteric control in a metalloprotein dramatically alters function.

    Science.gov (United States)

    Baxter, Elizabeth Leigh; Zuris, John A; Wang, Charles; Vo, Phu Luong T; Axelrod, Herbert L; Cohen, Aina E; Paddock, Mark L; Nechushtai, Rachel; Onuchic, Jose N; Jennings, Patricia A

    2013-01-15

    Metalloproteins (MPs) comprise one-third of all known protein structures. This diverse set of proteins contain a plethora of unique inorganic moieties capable of performing chemistry that would otherwise be impossible using only the amino acids found in nature. Most of the well-studied MPs are generally viewed as being very rigid in structure, and it is widely thought that the properties of the metal centers are primarily determined by the small fraction of amino acids that make up the local environment. Here we examine both theoretically and experimentally whether distal regions can influence the metal center in the diabetes drug target mitoNEET. We demonstrate that a loop (L2) 20 Å away from the metal center exerts allosteric control over the cluster binding domain and regulates multiple properties of the metal center. Mutagenesis of L2 results in significant shifts in the redox potential of the [2Fe-2S] cluster and orders of magnitude effects on the rate of [2Fe-2S] cluster transfer to an apo-acceptor protein. These surprising effects occur in the absence of any structural changes. An examination of the native basin dynamics of the protein using all-atom simulations shows that twisting in L2 controls scissoring in the cluster binding domain and results in perturbations to one of the cluster-coordinating histidines. These allosteric effects are in agreement with previous folding simulations that predicted L2 could communicate with residues surrounding the metal center. Our findings suggest that long-range dynamical changes in the protein backbone can have a significant effect on the functional properties of MPs.

  17. Altered goblet cell differentiation and surface mucus properties in Hirschsprung disease.

    Directory of Open Access Journals (Sweden)

    Jay R Thiagarajah

    Full Text Available Hirschsprung disease-associated enterocolitis (HAEC leads to significant mortality and morbidity, but its pathogenesis remains unknown. Changes in the colonic epithelium related to goblet cells and the luminal mucus layer have been postulated to play a key role. Here we show that the colonic epithelium of both aganglionic and ganglionic segments are altered in patients and in mice with Hirschsprung disease (HSCR. Structurally, goblet cells were altered with increased goblet cell number and reduced intracellular mucins in the distal colon of biopsies from patients with HSCR. Endothelin receptor B (Ednrb mutant mice showed increased goblet cell number and size and increased cell proliferation compared to wild-type mice in aganglionic segments, and reduced goblet cell size and number in ganglionic segments. Functionally, compared to littermates, Ednrb-/- mice showed increased transepithelial resistance, reduced stool water content and similar chloride secretion in the distal colon. Transcript levels of goblet cell differentiation factors SPDEF and Math1 were increased in the distal colon of Ednrb-/- mice. Both distal colon from Ednrb mice and biopsies from HSCR patients showed reduced Muc4 expression as compared to controls, but similar expression of Muc2. Particle tracking studies showed that mucus from Ednrb-/- mice provided a more significant barrier to diffusion of 200 nm nanoparticles as compared to wild-type mice. These results suggest that aganglionosis is associated with increased goblet cell proliferation and differentiation and subsequent altered surface mucus properties, prior to the development of inflammation in the distal colon epithelium. Restoration of normal goblet cell function and mucus layer properties in the colonic epithelium may represent a therapeutic strategy for prevention of HAEC.

  18. Altered neurotransmitter metabolism in adolescents with high-functioning autism

    NARCIS (Netherlands)

    Drenthen, G.S.; Barendse, E.M.; Aldenkamp, A.P.; Veenendaal, T. van; Puts, N.A.J.; Edden, R.A.E.; Zinger, S.; Thoonen, G.H.J.; Hendriks, M.P.H.; Kessels, R.P.C.; Jansen, J.F.A.

    2016-01-01

    Previous studies have suggested that alterations in excitatory/inhibitory neurotransmitters might play a crucial role in autism spectrum disorder (ASD). Proton magnetic resonance spectroscopy (1H-MRS) can provide valuable information about abnormal brain metabolism and neurotransmitter concentration

  19. Saturated fatty acids alter the late secretory pathway by modulating membrane properties.

    Science.gov (United States)

    Payet, Laurie-Anne; Pineau, Ludovic; Snyder, Ellen C R; Colas, Jenny; Moussa, Ahmed; Vannier, Brigitte; Bigay, Joelle; Clarhaut, Jonathan; Becq, Frédéric; Berjeaud, Jean-Marc; Vandebrouck, Clarisse; Ferreira, Thierry

    2013-12-01

    Saturated fatty acids (SFA) have been reported to alter organelle integrity and function in many cell types, including muscle and pancreatic β-cells, adipocytes, hepatocytes and cardiomyocytes. SFA accumulation results in increased amounts of ceramides/sphingolipids and saturated phospholipids (PL). In this study, using a yeast-based model that recapitulates most of the trademarks of SFA-induced lipotoxicity in mammalian cells, we demonstrate that these lipid species act at different levels of the secretory pathway. Ceramides mostly appear to modulate the induction of the unfolded protein response and the transcription of nutrient transporters destined to the cell surface. On the other hand, saturated PL, by altering membrane properties, directly impact vesicular budding at later steps in the secretory pathway, i.e. at the trans-Golgi Network level. They appear to do so by increasing lipid order within intracellular membranes which, in turn, alters the recruitment of loose lipid packing-sensing proteins, required for optimal budding, to nascent vesicles. We propose that this latter general mechanism could account for the well-documented deleterious impacts of fatty acids on the last steps of the secretory pathway in several cell types.

  20. Neuromorphological and wiring pattern alterations effects on brain function: a mixed experimental and computational approach.

    Directory of Open Access Journals (Sweden)

    Linus Manubens-Gil

    2015-04-01

    In addition, the study of fixed intact brains (by means of the state of the art CLARITY technique brings us closer to biologically and medically relevant situations, allowing not only to confirm whether the functional links in neuronal cultures are also present in vivo, but also enabling the introduction of functional information (like behavioral studies and functional imaging and another layer of structural alterations such as brain region morphology, neuronal density, and long-range connectivity. Taking together the experimental information from these systems we want to feed self-developed computational models that allow us to understand what are the fundamental characteristics of the observed connectivity patterns and the impact of each of the alterations on neuronal network function. These models will also provide a framework able to account for the emergent properties that bridge the gap between spontaneous electrical activity arousal/transmission and higher order information processing and memory storage capacities in the brain. As an additional part of the project we are now working on the application of the clearing, labeling and imaging protocols to human biopsy samples. Our aim is to obtain neuronal architecture and connectivity information from focal cortical dysplasia microcircuits using samples from intractable temporal lobe epilepsy patients that undergo deep-brain electrode recording diagnosis and posterior surgical extraction of the tissue. Our computational models can allow us to discern the contributions of the observed abnormalities to neuronal hyperactivity and epileptic seizure generation.

  1. Functional interpretation and the existence property

    DEFF Research Database (Denmark)

    Jørgensen, Klaus Frovin

    2004-01-01

    It is shown that functional interpretation can be used to show the existence property of intuitionistic number theory. On the basis of truth variants a comparison is then made between realisability and functional interpretation showing a structural difference between the two.......It is shown that functional interpretation can be used to show the existence property of intuitionistic number theory. On the basis of truth variants a comparison is then made between realisability and functional interpretation showing a structural difference between the two....

  2. Functional Task Test: 1. Sensorimotor changes Associated with Postflight Alterations in Astronaut Functional Task Performance

    Science.gov (United States)

    Bloomberg, J. J.; Arzeno, N. H.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Platts, S. H.; Peters, B. T.; Phillips, T.; Ploutz-Snyder, L. L.; Reschke, M. F.; Ryder, J. W.; Spiering, B. A.; Stenger, M. B.; Taylor, L. C.; Wickwire, P. J.; Wood, S. J.

    2011-01-01

    Space flight is known to cause alterations in multiple physiological systems including changes in sensorimotor, cardiovascular, and neuromuscular systems. These changes may affect a crewmember s ability to perform critical mission tasks immediately after landing on a planetary surface. The overall goal of this project is to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. This presentation will focus on the sensorimotor contributions to postflight functional performance.

  3. Frequency-specific Alterations of Large-scale Functional Brain Networks in Patients with Alzheimer's Disease

    Institute of Scientific and Technical Information of China (English)

    Yuan-Yuan Qin; Ya-Peng Li; Shun Zhang; Ying Xiong; Lin-Ying Guo; Shi-Qi Yang; Yi-Hao Yao

    2015-01-01

    Background:Previous studies have indicated that the cognitive deficits in patients with Alzheimer's disease (AD) may be due to topological deteriorations of the brain network.However,whether the selection of a specific frequency band could impact the topological properties is still not clear.Our hypothesis is that the topological properties of AD patients are also frequency-specific.Methods:Resting state functional magnetic resonance imaging data from l0 right-handed moderate AD patients (mean age:64.3 years; mean mini mental state examination [MMSE]:18.0) and 10 age and gender-matched healthy controls (mean age:63.6 years; mean MMSE:28.2) were enrolled in this study.The global efficiency,the clustering coefficient (CC),the characteristic path length (CpL),and "small-world" property were calculated in a wide range of thresholds and averaged within each group,at three different frequency bands (0.01-0.06 Hz,0.06-0.11 Hz,and 0.11-0.25 Hz).Results:At lower-frequency bands (0.01-0.06 Hz,0.06-0.11 Hz),the global efficiency,the CC and the "small-world" properties of AD patients decreased compared to controls.While at higher-frequency bands (0.11-0.25 Hz),the CpL was much longer,and the "small-world" property was disrupted in AD,particularly at a higher threshold.The topological properties changed with different frequency bands,suggesting the existence of disrupted global and local functional organization associated with AD.Conclusions:This study demonstrates that the topological alterations of large-scale functional brain networks inAD patients are frequency dependent,thus providing fundamental support for optimal frequency selection in future related research.

  4. Neutral genetic drift can alter promiscuous protein functions, potentially aiding functional evolution

    Directory of Open Access Journals (Sweden)

    Lu Zhongyi

    2007-06-01

    Full Text Available Abstract Background Many of the mutations accumulated by naturally evolving proteins are neutral in the sense that they do not significantly alter a protein's ability to perform its primary biological function. However, new protein functions evolve when selection begins to favor other, "promiscuous" functions that are incidental to a protein's original biological role. If mutations that are neutral with respect to a protein's primary biological function cause substantial changes in promiscuous functions, these mutations could enable future functional evolution. Results Here we investigate this possibility experimentally by examining how cytochrome P450 enzymes that have evolved neutrally with respect to activity on a single substrate have changed in their abilities to catalyze reactions on five other substrates. We find that the enzymes have sometimes changed as much as four-fold in the promiscuous activities. The changes in promiscuous activities tend to increase with the number of mutations, and can be largely rationalized in terms of the chemical structures of the substrates. The activities on chemically similar substrates tend to change in a coordinated fashion, potentially providing a route for systematically predicting the change in one activity based on the measurement of several others. Conclusion Our work suggests that initially neutral genetic drift can lead to substantial changes in protein functions that are not currently under selection, in effect poising the proteins to more readily undergo functional evolution should selection favor new functions in the future. Reviewers This article was reviewed by Martijn Huynen, Fyodor Kondrashov, and Dan Tawfik (nominated by Christoph Adami.

  5. Chronic zinc deficiency alters chick gut microbiota composition and function

    Science.gov (United States)

    Zinc (Zn) deficiency is a prevalent micronutrient insufficiency. Although the gut is a vital organ for Zn utilization, and Zn deficiency is associated with impaired intestinal permeability and a global decrease in gastrointestinal health, alterations in the gut microbial ecology of the host under co...

  6. Virus Innexins induce alterations in insect cell and tissue function

    Science.gov (United States)

    Polydnaviruses are dsDNA viruses that induce immune and developmental alterations in their caterpillar hosts. Characterization of polydnavirus gene families and family members is necessary to understand mechanisms of pathology and evolution of these viruses, and may aid to elucidate the role of host...

  7. Topological Properties of Spatial Coherence Function

    Institute of Scientific and Technical Information of China (English)

    REN Ji-Rong; ZHU Tao; DUAN Yi-Shi

    2008-01-01

    The topological properties of the spatial coherence function are investigated rigorously.The phase singular structures(coherence vortices)of coherence function can be naturally deduced from the topological current,which is an abstract mathematical object studied previously.We find that coherence vortices are characterized by the Hopf index and Brouwer degree in topology.The coherence flux quantization and the linking of the closed coherence vortices are also studied from the topological properties of the spatial coherence function.

  8. Vector-averaged gravity does not alter acetylcholine receptor single channel properties

    Science.gov (United States)

    Reitstetter, R.; Gruener, R.

    1994-01-01

    To examine the physiological sensitivity of membrane receptors to altered gravity, we examined the single channel properties of the acetylcholine receptor (AChR), in co-cultures of Xenopus myocytes and neurons, to vector-averaged gravity in the clinostat. This experimental paradigm produces an environment in which, from the cell's perspective, the gravitational vector is "nulled" by continuous averaging. In that respect, the clinostat simulates one aspect of space microgravity where the gravity force is greatly reduced. After clinorotation, the AChR channel mean open-time and conductance were statistically not different from control values but showed a rotation-dependent trend that suggests a process of cellular adaptation to clinorotation. These findings therefore suggest that the ACHR channel function may not be affected in the microgravity of space despite changes in the receptor's cellular organization.

  9. Long-term oil contamination alters the molecular ecological networks of soil microbial functional genes

    Directory of Open Access Journals (Sweden)

    Yuting eLiang

    2016-02-01

    Full Text Available With knowledge on microbial composition and diversity, investigation of within-community interactions is a further step to elucidate microbial ecological functions, such as the biodegradation of hazardous contaminants. In this work, microbial functional molecular ecological networks were studied in both contaminated and uncontaminated soils to determine the possible influences of oil contamination on microbial interactions and potential functions. Soil samples were obtained from an oil-exploring site located in South China, and the microbial functional genes were analyzed with GeoChip, a high-throughput functional microarray. By building random networks based on null model, we demonstrated that overall network structures and properties were significantly different between contaminated and uncontaminated soils (P < 0.001. Network connectivity, module numbers, and modularity were all reduced with contamination. Moreover, the topological roles of the genes (module hub and connectors were altered with oil contamination. Subnetworks of genes involved in alkane and polycyclic aromatic hydrocarbon degradation were also constructed. Negative co-occurrence patterns prevailed among functional genes, thereby indicating probable competition relationships. The potential keystone genes, defined as either hubs or genes with highest connectivities in the network, were further identified. The network constructed in this study predicted the potential effects of anthropogenic contamination on microbial community co-occurrence interactions.

  10. Functional barriers: Properties and evaluation

    NARCIS (Netherlands)

    Feigenbaum, A.; Dole, P.; Aucejo, S.; Dainelli, D.; Cruz Garcia, C. de la; Hankemeier, T.; N'Gono, Y.; Papaspyrides, C.D.; Paseiro, P.; Pastorelli, S.; Pavlidou, S.; Pennarun, P.Y.; Saillard, P.; Vidal, L.; Vitrac, O.; Voulzatis, Y.

    2005-01-01

    Functional barriers are multilayer structures deemed to prevent migration of some chemicals released by food-contact materials into food. In the area of plastics packaging, different migration behaviours of mono- and multilayer structures are assessed in terms of lag time and of their influence of t

  11. PROPERTY. ABSOLUT RIGHT. SOCIAL FUNCTION

    Directory of Open Access Journals (Sweden)

    Lucia Maria COŞTIUG

    2016-07-01

    Full Text Available The article presents the opinion according to which today we can speak rather of a relative character of ownership, while the social function of it is ever more present and the rights of the owner are subject to multiple legal requirements and limited in order to meet general interests of the community.

  12. Ocean acidification alters the material properties of Mytilus edulis shells.

    Science.gov (United States)

    Fitzer, Susan C; Zhu, Wenzhong; Tanner, K Elizabeth; Phoenix, Vernon R; Kamenos, Nicholas A; Cusack, Maggie

    2015-02-01

    Ocean acidification (OA) and the resultant changing carbonate saturation states is threatening the formation of calcium carbonate shells and exoskeletons of marine organisms. The production of biominerals in such organisms relies on the availability of carbonate and the ability of the organism to biomineralize in changing environments. To understand how biomineralizers will respond to OA the common blue mussel, Mytilus edulis, was cultured at projected levels of pCO2 (380, 550, 750, 1000 µatm) and increased temperatures (ambient, ambient plus 2°C). Nanoindentation (a single mussel shell) and microhardness testing were used to assess the material properties of the shells. Young's modulus (E), hardness (H) and toughness (KIC) were measured in mussel shells grown in multiple stressor conditions. OA caused mussels to produce shell calcite that is stiffer (higher modulus of elasticity) and harder than shells grown in control conditions. The outer shell (calcite) is more brittle in OA conditions while the inner shell (aragonite) is softer and less stiff in shells grown under OA conditions. Combining increasing ocean pCO2 and temperatures as projected for future global ocean appears to reduce the impact of increasing pCO2 on the material properties of the mussel shell. OA may cause changes in shell material properties that could prove problematic under predation scenarios for the mussels; however, this may be partially mitigated by increasing temperature.

  13. Functional Properties of Microorganisms in Fermented Foods

    Directory of Open Access Journals (Sweden)

    Jyoti Prakash Tamang

    2016-04-01

    Full Text Available Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers.

  14. Quantitative, functional and biochemical alterations in the peritoneal cells of mice exposed to whole-body gamma-irradiation. 1. Changes in cellular protein, adherence properties and enzymatic activities associated with platelet-activating factor formation and inactivation

    Energy Technology Data Exchange (ETDEWEB)

    Steel, L.K.; Hughes, H.N.; Walden, T.L. Jr.

    1988-06-01

    Changes in total number, differentials, cell protein, adherence properties, acetyl-CoA transferase and acetylhydrolase activities, prostaglandin E/sub 2/ and leukotriene C/sub 4/ production, as well as Ca/sup 2+/ ionophore A23187 stimulation were examined in resident peritoneal cells isolated from mice 2 h to 10 days postexposure to a single dose (7, 10 or 12 Gy) of gamma-radiation. Radiation dose-related reductions in macrophage and lymphocyte numbers and increases in cellular protein and capacity to adhere to plastic surfaces were evident. In vivo irradiation also elevated the activities of acetyltransferase and acetyl-CoA hydrolase (catalysing platelet-activating factor biosynthesis and inactivation, respectively) in adherent and nonadherent peritoneal cells, particularly 3-4 days postexposure. Blood plasma from irradiated animals did not reflect the increased cellular acetyl-hydrolase activity. Prostaglandin E/sub 2/ and leukotriene C/sub 4/ synthesis were elevated postexposure, suggesting increased substrate (arachidonate) availability and increased cyclooxygenase and lipoxygenase activities. Ionophore stimulation of enzyme activities and eicosanoid release also differed in irradiated peritoneal cells.

  15. How do brain tumors alter functional connectivity? : A magnetoencephalography study

    NARCIS (Netherlands)

    Bartolomei, Fabrice; Bosma, Ingeborg; Klein, Martin; Baayen, Johannes C; Reijneveld, Jaap C; Postma, Tjeerd J; Heimans, Jan J; van Dijk, Bob W; de Munck, Jan C; de Jongh, Arent; Cover, Keith S; Stam, Cornelis J

    2006-01-01

    OBJECTIVE: This study was undertaken to test the hypothesis that brain tumors interfere with normal brain function by disrupting functional connectivity of brain networks. METHODS: Functional connectivity was assessed by computing the synchronization likelihood in a broad band (0.5-60Hz) or in the g

  16. Peritoneal culture alters Streptococcus pneumoniae protein profiles and virulence properties

    Science.gov (United States)

    Orihuela, C. J.; Janssen, R.; Robb, C. W.; Watson, D. A.; Niesel, D. W.

    2000-01-01

    We have examined the properties of Streptococcus pneumoniae cultured in the murine peritoneal cavity and compared its virulence-associated characteristics to those of cultures grown in vitro. Analysis of mRNA levels for specific virulence factors demonstrated a 2.8-fold increase in ply expression and a 2.2-fold increase in capA3 expression during murine peritoneal culture (MPC). Two-dimensional gels and immunoblots using convalescent-phase patient sera and murine sera revealed distinct differences in protein production in vivo (MPC). MPC-grown pneumococci adhered to A549 epithelial cell lines at levels 10-fold greater than those cultured in vitro.

  17. Altering properties of cerium oxide thin films by Rh doping

    Energy Technology Data Exchange (ETDEWEB)

    Ševčíková, Klára, E-mail: klarak.sevcikova@seznam.cz [Faculty of Mathematics and Physics, Department of Surface and Plasma Science, Charles University in Prague, V Holešovičkách 2, 180 00 Prague 8 (Czech Republic); NIMS Beamline Station at SPring-8, National Institute for Materials Science, Sayo, Hyogo 679-5148 (Japan); Nehasil, Václav, E-mail: nehasil@mbox.troja.mff.cuni.cz [Faculty of Mathematics and Physics, Department of Surface and Plasma Science, Charles University in Prague, V Holešovičkách 2, 180 00 Prague 8 (Czech Republic); Vorokhta, Mykhailo, E-mail: vorohtam@gmail.com [Faculty of Mathematics and Physics, Department of Surface and Plasma Science, Charles University in Prague, V Holešovičkách 2, 180 00 Prague 8 (Czech Republic); Haviar, Stanislav, E-mail: stanislav.haviar@gmail.com [Faculty of Mathematics and Physics, Department of Surface and Plasma Science, Charles University in Prague, V Holešovičkách 2, 180 00 Prague 8 (Czech Republic); Matolín, Vladimír, E-mail: matolin@mbox.troja.mff.cuni.cz [Faculty of Mathematics and Physics, Department of Surface and Plasma Science, Charles University in Prague, V Holešovičkách 2, 180 00 Prague 8 (Czech Republic); and others

    2015-07-15

    Highlights: • Thin films of ceria doped by rhodium deposited by RF magnetron sputtering. • Concentration of rhodium has great impact on properties of Rh–CeO{sub x} thin films. • Intensive oxygen migration in films with low concentration of rhodium. • Oxygen migration suppressed in films with high amount of Rh dopants. - Abstract: Ceria containing highly dispersed ions of rhodium is a promising material for catalytic applications. The Rh–CeO{sub x} thin films with different concentrations of rhodium were deposited by RF magnetron sputtering and were studied by soft and hard X-ray photoelectron spectroscopies, Temperature programmed reaction and X-ray powder diffraction techniques. The sputtered films consist of rhodium–cerium mixed oxide where cerium exhibits a mixed valency of Ce{sup 4+} and Ce{sup 3+} and rhodium occurs in two oxidation states, Rh{sup 3+} and Rh{sup n+}. We show that the concentration of rhodium has a great influence on the chemical composition, structure and reducibility of the Rh–CeO{sub x} thin films. The films with low concentrations of rhodium are polycrystalline, while the films with higher amount of Rh dopants are amorphous. The morphology of the films strongly influences the mobility of oxygen in the material. Therefore, varying the concentration of rhodium in Rh–CeO{sub x} thin films leads to preparing materials with different properties.

  18. Resveratrol: preventing properties against vascular alterations and ageing.

    Science.gov (United States)

    Delmas, Dominique; Jannin, Brigitte; Latruffe, Norbert

    2005-05-01

    Cardiovascular diseases are the leading cause of death in developed countries where the common pathological substrate underlying this process is atherosclerosis. Several new concepts have emerged in relation to mechanisms that contribute to the regulation of the vascular diseases and associated inflammatory effects. Recently, potential antioxidants (vitamin E, polyphenols) have received much attention as potential anti-atherosclerotic agents. Among the polyphenols with health benefic properties, resveratrol, a phytoalexin of grape, seem to be a good candidate protecting the vascular walls from oxidation, inflammation, platelet aggregation, and thrombus formation. In this review, we focus on the mechanism of resveratrol cardiovascular benefic effects. We analyze, in relation with the different steps of atherosclerotic process, the resveratrol properties at multiple levels, such as cellular signaling, enzymatic pathways, apoptosis, and gene expression. We show and discuss the relationship with reactive oxygen species, regulation of pro-inflammatory genes including cycloxygenases and cytokines in molecular inflammatory and aging processes, and how the regulation of these activites by resveratrol can lead to a prevention of vascular diseases.

  19. Functional alterations in neural substrates of geometric reasoning in adults with high-functioning autism.

    Directory of Open Access Journals (Sweden)

    Takashi Yamada

    Full Text Available Individuals with autism spectrum condition (ASC are known to excel in some perceptual cognitive tasks, but such developed functions have been often regarded as "islets of abilities" that do not significantly contribute to broader intellectual capacities. However, recent behavioral studies have reported that individuals with ASC have advantages for performing Raven's (Standard Progressive Matrices (RPM/RSPM, a standard neuropsychological test for general fluid intelligence, raising the possibility that ASC's cognitive strength can be utilized for more general purposes like novel problem solving. Here, the brain activity of 25 adults with high-functioning ASC and 26 matched normal controls (NC was measured using functional magnetic resonance imaging (fMRI to examine neural substrates of geometric reasoning during the engagement of a modified version of the RSPM test. Among the frontal and parietal brain regions involved in fluid intelligence, ASC showed larger activation in the left lateral occipitotemporal cortex (LOTC during an analytic condition with moderate difficulty than NC. Activation in the left LOTC and ventrolateral prefrontal cortex (VLPFC increased with task difficulty in NC, whereas such modulation of activity was absent in ASC. Furthermore, functional connectivity analysis revealed a significant reduction of activation coupling between the left inferior parietal cortex and the right anterior prefrontal cortex during both figural and analytic conditions in ASC. These results indicate altered pattern of functional specialization and integration in the neural system for geometric reasoning in ASC, which may explain its atypical cognitive pattern, including performance on the Raven's Matrices test.

  20. Altered functional brain connectivity in a non-clinical sample of young adults with attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Cocchi, Luca; Bramati, Ivanei E; Zalesky, Andrew; Furukawa, Emi; Fontenelle, Leonardo F; Moll, Jorge; Tripp, Gail; Mattos, Paulo

    2012-12-05

    Attention-deficit/hyperactivity disorder (ADHD) is characterized by symptoms of inattention and hyperactivity/impulsivity that often persist in adulthood. There is a growing consensus that ADHD is associated with abnormal function of diffuse brain networks, but such alterations remain poorly characterized. Using resting-state functional magnetic resonance imaging, we characterized multivariate (complex network measures), bivariate (network-based statistic), and univariate (regional homogeneity) properties of brain networks in a non-clinical, drug-naive sample of high-functioning young men and women with ADHD (nine males, seven females) and a group of matched healthy controls. Data from our sample allowed the isolation of intrinsic functional connectivity alterations specific to ADHD diagnosis and symptoms that are not related to developmental delays, general cognitive dysfunction, or history of medication use. Multivariate results suggested that frontal, temporal, and occipital cortices were abnormally connected locally as well as with the rest of the brain in individuals with ADHD. Results from the network-based statistic support and extend multivariate results by isolating two brain networks comprising regions between which inter-regional connectivity was significantly altered in the ADHD group; namely, a frontal amygdala-occipital network and a frontal temporal-occipital network. Brain behavior correlations further highlighted the key role of altered orbitofrontal-temporal and frontal-amygdala connectivity for symptoms of inattention and hyperactivity/impulsivity. All univariate properties were similar between groups. Taken together, results from this study show that the diagnosis and the two main symptom dimensions of ADHD are related to altered intrinsic connectivity in orbitofrontal-temporal-occipital and fronto-amygdala-occipital networks. Accordingly, our findings highlight the importance of extending the conceptualization of ADHD beyond segregated fronto

  1. Analytical properties of credibilistic expectation functions.

    Science.gov (United States)

    Wang, Shuming; Wang, Bo; Watada, Junzo

    2014-01-01

    The expectation function of fuzzy variable is an important and widely used criterion in fuzzy optimization, and sound properties on the expectation function may help in model analysis and solution algorithm design for the fuzzy optimization problems. The present paper deals with some analytical properties of credibilistic expectation functions of fuzzy variables that lie in three aspects. First, some continuity theorems on the continuity and semicontinuity conditions are proved for the expectation functions. Second, a differentiation formula of the expectation function is derived which tells that, under certain conditions, the derivative of the fuzzy expectation function with respect to the parameter equals the expectation of the derivative of the fuzzy function with respect to the parameter. Finally, a law of large numbers for fuzzy variable sequences is obtained leveraging on the Chebyshev Inequality of fuzzy variables. Some examples are provided to verify the results obtained.

  2. Altered islet morphology but normal islet secretory function in vitro in a mouse model with microvascular alterations in the pancreas.

    Directory of Open Access Journals (Sweden)

    Elena Kostromina

    Full Text Available BACKGROUND: Our previous studies have shown that signal transducer and activator of transcription 3 (STAT3 signaling is important for the development of pancreatic microvasculature via its regulation of vascular endothelial growth factor-A (VEGF-A. Pancreas-specific STAT3-KO mice exhibit glucose intolerance and impaired insulin secretion in vivo, along with microvascular alterations in the pancreas. However, the specific role of STAT3 signaling in the regulation of pancreatic islet development and function is not entirely understood. METHODOLOGY/PRINCIPAL FINDINGS: To investigate the role of STAT3 signaling in the formation and maintenance of pancreatic islets, we studied pancreas-specific STAT3-KO mice. Histological analysis showed that STAT3 deficiency affected pancreatic islet morphology. We found an increased proportion of small-sized islets and a reduced fraction of medium-sized islets, indicating abnormal islet development in STAT3-KO mice. Interestingly, the islet area relative to the whole pancreas area in transgenic and control mice was not significantly different. Immunohistochemical analysis on pancreatic cryosections revealed abnormalities in islet architecture in STAT3-KO mice: the pattern of peripheral distribution of glucagon-positive α-cells was altered. At the same time, islets belonging to different size categories isolated from STAT3-KO mice exhibited normal glucose-stimulated insulin secretion in perifusion experiments in vitro when compared to control mice. CONCLUSIONS: Our data demonstrate that STAT3 signaling in the pancreas is required for normal islet formation and/or maintenance. Altered islet size distribution in the KO mice does not result in an impaired islet secretory function in vitro. Therefore, our current study supports that the glucose intolerance and in vivo insulin secretion defect in pancreas-specific STAT3-KO mice is due to altered microvasculature in the pancreas, and not intrinsic beta-cell function.

  3. Role and properties of the gel formed during nuclear glass alteration: importance of gel formation conditions

    Science.gov (United States)

    Gin, S.; Ribet, I.; Couillard, M.

    2001-09-01

    A French SON 68 nuclear glass sample was experimentally altered to assess the mechanisms limiting the glass alteration kinetics, especially during the transition phase between the initial rate r0 and the final rate under silicon saturation conditions. A glass specimen was altered at the initial rate for one week to form a silicon-depleted non-protective gel; the specimen was then leached under static conditions at a glass-surface-to-solution-volume ( S/ V) ratio of 500 m-1 and the alteration kinetics were compared with those of a pristine glass specimen altered under the same conditions. Unexpectedly, after static leaching the previously leached glass was 2.7 times as altered as the pristine specimen, and the steady-state silicon concentration was twice as high for the previously leached specimen. STEM characterization of the alteration films showed that the initial non-protective gel constituted a silicon pump with respect to the glass, and that the glass alteration kinetics were limited only when a fraction of the gel became saturated with silicon, and exhibited protective properties. This work also shows that silicon recondensation was uniform at micrometer scale: the silicon hydrolyzed at the reaction interface then diffused before recondensing over a length comparable to the gel thickness. In addition to these findings, this investigation suggests a reinterpretation of the effect of the S/ V ratio on the glass alteration kinetics and on the steady-state dissolved silicon concentration.

  4. Nanostructured thin films and coatings functional properties

    CERN Document Server

    Zhang, Sam

    2010-01-01

    The second volume in ""The Handbook of Nanostructured Thin Films and Coatings"" set, this book focuses on functional properties, including optical, electronic, and electrical properties, as well as related devices and applications. It explores the large-scale fabrication of functional thin films with nanoarchitecture via chemical routes, the fabrication and characterization of SiC nanostructured/nanocomposite films, and low-dimensional nanocomposite fabrication and applications. The book also presents the properties of sol-gel-derived nanostructured thin films as well as silicon nanocrystals e

  5. Prenatal stress alters amygdala functional connectivity in preterm neonates

    Directory of Open Access Journals (Sweden)

    Dustin Scheinost

    2016-01-01

    Functional connectivity from the amygdala to other subcortical regions is decreased in preterm neonates compared to term controls. In addition, these data, for the first time, suggest that prenatal stress exposure amplifies these decreases.

  6. [Functional alterations in the retina following a 10 Gy gamma irradiation localized in the eye].

    Science.gov (United States)

    Bagot, J D; Courant, D; Court, L

    1980-11-17

    A single-eye irradiation of 10 Gy (0.8 Gy. min-1) induces impairments of the electrical responses of the rabbit retina in dark adaptation. These are associated with reversible alteration of the photoreceptors and the preganglionic neurons and a disturbance of all the mechanisms of adaptation. Possible relationships between these functional alterations and the effects of irradiation are discussed.

  7. Kaempferol inhibits Entamoeba histolytica growth by altering cytoskeletal functions.

    Science.gov (United States)

    Bolaños, Verónica; Díaz-Martínez, Alfredo; Soto, Jacqueline; Marchat, Laurence A; Sanchez-Monroy, Virginia; Ramírez-Moreno, Esther

    2015-11-01

    The flavonoid kaempferol obtained from Helianthemum glomeratum, an endemic Mexican medicinal herb used to treat gastrointestinal disorders, has been shown to inhibit growth of Entamoeba histolytica trophozoites in vitro; however, the mechanisms associated with this activity have not been documented. Several works reported that kaempferol affects cytoskeleton in mammalian cells. In order to gain insights into the action mechanisms involved in the anti-amoebic effect of kaempferol, here we evaluated the effect of this compound on the pathogenic events driven by the cytoskeleton during E. histolytica infection. We also carried out a two dimensional gel-based proteomic analysis to evidence modulated proteins that could explain the phenotypical changes observed in trophozoites. Our results showed that kaempferol produces a dose-dependent effect on trophozoites growth and viability with optimal concentration being 27.7 μM. Kaempferol also decreased adhesion, it increased migration and phagocytic activity, but it did not affect erythrocyte binding nor cytolytic capacity of E. histolytica. Congruently, proteomic analysis revealed that the cytoskeleton proteins actin, myosin II heavy chain and cortexillin II were up-regulated in response to kaempferol treatment. In conclusion, kaempferol anti-amoebic effects were associated with deregulation of proteins related with cytoskeleton, which altered invasion mechanisms.

  8. Abdominal Pain, the Adolescent and Altered Brain Structure and Function.

    Directory of Open Access Journals (Sweden)

    Catherine S Hubbard

    Full Text Available Irritable bowel syndrome (IBS is a functional gastrointestinal (GI disorder of unknown etiology. Although relatively common in children, how this condition affects brain structure and function in a pediatric population remains unclear. Here, we investigate brain changes in adolescents with IBS and healthy controls. Imaging was performed with a Siemens 3 Tesla Trio Tim MRI scanner equipped with a 32-channel head coil. A high-resolution T1-weighted anatomical scan was acquired followed by a T2-weighted functional scan. We used a surface-based morphometric approach along with a seed-based resting-state functional connectivity (RS-FC analysis to determine if groups differed in cortical thickness and whether areas showing structural differences also showed abnormal RS-FC patterns. Patients completed the Abdominal Pain Index and the GI Module of the Pediatric Quality of Life Inventory to assess abdominal pain severity and impact of GI symptoms on health-related quality of life (HRQOL. Disease duration and pain intensity were also assessed. Pediatric IBS patients, relative to controls, showed cortical thickening in the posterior cingulate (PCC, whereas cortical thinning in posterior parietal and prefrontal areas were found, including the dorsolateral prefrontal cortex (DLPFC. In patients, abdominal pain severity was related to cortical thickening in the intra-abdominal area of the primary somatosensory cortex (SI, whereas HRQOL was associated with insular cortical thinning. Disease severity measures correlated with cortical thickness in bilateral DLPFC and orbitofrontal cortex. Patients also showed reduced anti-correlations between PCC and DLPFC compared to controls, a finding that may reflect aberrant connectivity between default mode and cognitive control networks. We are the first to demonstrate concomitant structural and functional brain changes associated with abdominal pain severity, HRQOL related to GI-specific symptoms, and disease

  9. Adrenal morpho-functional alterations in patients with acromegaly.

    Science.gov (United States)

    Scaroni, C; Selice, R; Benedini, S; De Menis, E; Arosio, M; Ronchi, C; Gasperi, M; Manetti, L; Arnaldi, G; Polenta, B; Boscaro, M; Albiger, N; Martino, E; Mantero, F

    2008-07-01

    Acromegaly is associated with a greater morbidity and higher incidence of tumors, possibly due to the permissive role of elevated GH and IGF-I levels. In the general population, adrenal masses are frequently discovered (prevalence 1-5%) at computed tomography (CT). We evaluated the prevalence of adrenal lesions in patients with acromegaly. We studied 94 acromegalic patients, 54 females (mean age 55.0+/-16.0 yr) and 40 males (mean age 50+/-14 yr) referred to 5 Endocrinology Units between 2001-2003; 49 had active disease and 45 had been treated with surgery and/or were controlled with medical therapy. Abdominal CT showed adrenal lesions in 27 patients; 9 of them had unilateral masses (10%) with benign features (diameter 0.5-3 cm) and 18 had hyperplasia (14 monolateral and 4 bilateral), with no significant differences between patients with active vs controlled disease, and with no correlation between prevalence of masses and duration of disease, GH and IGF-I levels. Hormone study (urinary free cortisol, catecholamines/metanephrines, upright plasma renin activity and aldosterone, morning plasma ACTH and low-dose dexamethasone suppression test) disclosed no major endocrine alterations. During a 1-yr follow-up, the adrenal masses increased in size in 3 cases and 1 patient also developed subclinical Cushing's syndrome. Adrenal lesions seem more frequent in acromegaly than in the general population, but no single factor (GH/IGF-I levels or disease duration) predicts them. The masses appear to be benign and nonhypersecreting, but a longer follow-up is recommended to disclose any changes in their morphofunctional state.

  10. Altered multiaxial mechanical properties of the porcine anterior lens capsule cultured in high glucose.

    Science.gov (United States)

    Pedrigi, R M; Staff, E; David, G; Glenn, S; Humphrey, J D

    2007-02-01

    Hyperglycemia can alter the mechanical properties of tissues through the formation of advanced glycation endproducts in matrix proteins that have long half-lives. We used a custom experimental system and subdomain finite element method to quantify alterations in the regional multiaxial mechanical properties of porcine lens capsules that were cultured for 8 or 14 weeks in high glucose versus control media. Findings revealed that high glucose significantly stiffened the capsules in both the circumferential and the meridional directions, but it did not affect the known regional variations in anisotropy. Such information could be important in the design of both improved clinical procedures and intraocular implants for diabetic patients.

  11. GABA FUNCTION IS ALTERED FOLLOWING DEVELOPMENTAL HYPOTHYROIDISM: NEUROANATOMICAL AND NEUROPHYSIOLOGICAL EVIDENCE.

    Science.gov (United States)

    Thyroid hormone deficiency during development produces changes in the structure of neurons and glial cells and alters synaptic function in the hippocampus. GABAergic interneurons comprise the bulk of local inhibitory neuronal circuitry and a subpopulation of these interneurons ...

  12. PCBs Alter Dopamine Mediated Function in Aging Workers

    Science.gov (United States)

    2011-01-01

    Learning slope BDI (+) CVLT, Proactive Interference (List B Compared to List A trial 1) Direct Solvent Exposure Based on Hobbies, Osteoporosis , Other...an effect largely prevented by estrogen supplementation (Dluzen, 2000; Miller et al., 1998)—we included sex as a variable in all statistical analyses...et al., 2003; Jaber et al., 1997), modulationof DATdensity or function bypostmenopausal reductions in central estrogen may interact with PCBs

  13. Alterations of Blood Brain Barrier Function in Hyperammonemia: An Overview

    OpenAIRE

    2011-01-01

    Ammonia is a neurotoxin involved in the pathogenesis of neurological conditions associated with hyperammonemia, including hepatic encephalopathy, a condition associated with acute—(ALF) or chronic liver failure. This article reviews evidence that apart from directly affecting the metabolism and function of the central nervous system cells, ammonia influences the passage of different molecules across the blood brain barrier (BBB). A brief description is provided of the tight junctions, which c...

  14. Does drought alter hydrological functions in forest soils?

    Science.gov (United States)

    Gimbel, Katharina F.; Puhlmann, Heike; Weiler, Markus

    2016-04-01

    Climate change is expected to impact the water cycle and severely affect precipitation patterns across central Europe and in other parts of the world, leading to more frequent and severe droughts. Usually when projecting drought impacts on hydrological systems, it is assumed that system properties, like soil properties, remain stable and will not be affected by drought events. To study if this assumption is appropriate, we address the effects of drought on the infiltration behavior of forest soils using dye tracer experiments on six sites in three regions across Germany, which were forced into drought conditions. The sites cover clayey-, loamy- and sandy-textured soils. In each region, we compared a deciduous and a coniferous forest stand to address differences between the main tree species. The results of the dye tracer experiments show clear evidence for changes in infiltration behavior at the sites. The infiltration changed at the clayey plots from regular and homogeneous flow to fast preferential flow. Similar behavior was observed at the loamy plots, where large areas in the upper layers remained dry, displaying signs of strong water repellency. This was confirmed by water drop penetration time (WDPT) tests, which revealed, in all except one plot, moderate to severe water repellency. Water repellency was also accountable for the change of regular infiltration to fingered flow in the sandy soils. The results of this study suggest that the drought history or, more generally, the climatic conditions of a soil in the past are more important than the actual antecedent soil moisture status regarding hydrophobicity and infiltration behavior; furthermore, drought effects on infiltration need to be considered in hydrological models to obtain realistic predictions concerning water quality and quantity in runoff and groundwater recharge.

  15. Altered colonic function and microbiota profile in a mouse model of chronic depression

    OpenAIRE

    Park, A J; COLLINS, J.; Blennerhassett, P. A.; Ghia, J E; Verdu, E F; Bercik, P; Collins, S.M.

    2013-01-01

    Background Depression often coexists with the irritable bowel syndrome (IBS) which is characterized by alterations in gut function. There is emerging evidence that the microbial composition (microbiota) of the gut is altered in IBS, but the basis for this is poorly understood. The aim of this study was to determine whether the induction of chronic depression results in changes in the colonic function and in its microbial community, and to explore underlying mechanisms. Methods Bilateral olfac...

  16. Characterizing genomic alterations in cancer by complementary functional associations | Office of Cancer Genomics

    Science.gov (United States)

    Systematic efforts to sequence the cancer genome have identified large numbers of mutations and copy number alterations in human cancers. However, elucidating the functional consequences of these variants, and their interactions to drive or maintain oncogenic states, remains a challenge in cancer research. We developed REVEALER, a computational method that identifies combinations of mutually exclusive genomic alterations correlated with functional phenotypes, such as the activation or gene dependency of oncogenic pathways or sensitivity to a drug treatment.

  17. Investigation of Biogeochemical Functional Proxies in Headwater Streams Across a Range of Channel and Catchment Alterations

    Science.gov (United States)

    Berkowitz, Jacob F.; Summers, Elizabeth A.; Noble, Chris V.; White, John R.; DeLaune, Ronald D.

    2014-03-01

    Historically, headwater streams received limited protection and were subjected to extensive alteration from logging, farming, mining, and development activities. Despite these alterations, headwater streams provide essential ecological functions. This study examines proxy measures of biogeochemical function across a range of catchment alterations by tracking nutrient cycling (i.e., inputs, processing, and stream loading) with leaf litter fall, leaf litter decomposition, and water quality parameters. Nutrient input and processing remained highest in second growth forests (the least altered areas within the region), while recently altered locations transported higher loads of nutrients, sediments, and conductivity. Biogeochemical functional proxies of C and N input and processing significantly, positively correlated with rapid assessment results (Pearson coefficient = 0.67-0.81; P = 0.002-0.016). Additionally, stream loading equations demonstrate that N and P transport, sediment, and specific conductivity negatively correlated with rapid assessment scores (Pearson coefficient = 0.56-0.81; P = 0.002-0.048). The observed increase in stream loading with lower rapid assessment scores indicates that catchment alterations impact stream chemistry and that rapid assessments provide useful proxy measures of function in headwater ecosystems. Significant differences in nutrient processing, stream loading, water quality, and rapid assessment results were also observed between recently altered (e.g., mined) headwater streams and older forested catchments (Mann-Whitney U = 24; P = 0.01-0.024). Findings demonstrate that biogeochemical function is reduced in altered catchments, and rapid assessment scores respond to a combination of alteration type and recovery time. An analysis examining time and economic requirements of proxy measurements highlights the benefits of rapid assessment methods in evaluating biogeochemical functions.

  18. Altering Cardiac Function via Transgenesis A Nuts and Bolts Approach.

    Science.gov (United States)

    Robbins, J

    1997-08-01

    Transgenesis provides a means to modify the mammalian genome. By directing expression of a engineered protein to the heart, one now is able to remodel effectively the cardiac protein profile and study the consequences of a single genetic manipulation at the molecular, biochemical, cytological, and physiologic levels. Often, a particular pathology or even a global remodeling process such as hypertrophy is accompanied by the upregulation or downregulation of a gene or set(s) of genes. What is not known is whether these changes represent a beneficial compensatory response or contribute to the continued degeneration of normal heart function. The ability to perform genetic manipulations on cardiac gene expression via transgenesis offers one a rapid and effective means of extending the correlations noted to the mechanistic level. Now, one can, in theory, express a candidate protein at a particular developmental time and determine the direct consequences of its appearance. Similarly, one can explore structure-function relationships, both between different forms of a protein family and in terms of active domains within a protein, by expressing a transgene that encodes a suitable mutation or ectopic protein isoform. This review explores the practical considerations of the transgenic approach in terms of what is important for a successful experiment from the necessary animal husbandry to designing constructs that will express at appropriate levels in the heart. (Trends Cardiovasc Med 1997;7:185-191). © 1997, Elsevier Science Inc.

  19. Alterations of hydraulic soil properties influenced by land-use changes and agricultural management systems

    Science.gov (United States)

    Weninger, Thomas; Kreiselmeier, Janis; Chandrasekhar, Parvathy; Jülich, Stefan; Schwärzel, Kai; Schwen, Andreas

    2016-04-01

    Estimation and modeling of soil water movement and the hydrologic balance of soils requires sound knowledge about hydraulic soil properties (HSP). The soil water characteristics, the hydraulic conductivity function and the pore size distribution (PSD) are commonly used instruments for the mathematical representation of HSP. Recent research highlighted the temporal variability of these functions caused by meteorological or land-use influences. State of the art modeling software for the continuous simulation of soil water movement uses a stationary approach for the HSP which means that their time dependent alterations and the subsequent effects on soil water balance is not considered. Mathematical approaches to describe the evolution of PSD are nevertheless known, but there is a lack of sound data basis for parameter estimation. Based on extensive field and laboratory measurements at 5 locations along a climatic gradient across Austria and Germany, this study will quantify short-term changes in HSP, detect driving forces and introduce a method to predict the effects of soil and land management actions on the soil water balance. Amongst several soil properties, field-saturated and unsaturated hydraulic conductivities will be determined using a hood infiltration experiments in the field as well as by evaporation and dewpoint potentiometer method in the lab. All measurements will be carried out multiple times over a span of 2 years which will allow a detailed monitoring of changes in HSP. Experimental sites where we expect significant inter-seasonal changes will be equipped with sensors for soil moisture and matric potential. The choice of experimental field sites follows the intention to involve especially the effects of tillage operations, different cultivation strategies, microclimatically effective structures and land-use changes. The international project enables the coverage of a broad range of soil types as well as climate conditions and hence will have broad

  20. Alterations of CNS structure & function by charged particle radiation & resultant oxidative stress

    Science.gov (United States)

    Nelson, Gregory; Chang, Polly; Favre, Cecile; Fike, John; Komarova, Natalia; Limoli, Charles; Mao, Xiao-Wen; Obenaus, Andre; Raber, Jacob; Spigelman, Igor; Soltesz, Ivan; Song, Sheng-Kwei; Stampanoni, Marco; Vlkolinsky, Roman; Wodarz, Dominik

    The NSCOR program project is transitioning from establishing the existence of CNS responses to low doses of charged particles, to an investigation of mechanisms underlying these changes and extending the irradiation paradigm to more space-like exposures. In earlier experiments we examined radiation responses of the mouse brain (hippocampus) following exposure to 250 MeV protons and 600 MeV/n iron ions. Our key findings on structural changes were: 1) Significant dose and time dependent loss of en-dothelial cells and microvessel network remodeling occurs suggesting that vascular insufficiency is produced. 2) Significant dose dependent losses of neural precursor cells were observed in a lineage specific pattern which may be associated with cognitive impairment. 3) Evaluation of DNA damage showed dose and time dependent accumulation of mutations with region-specific mutation structures and gene expression profiling demonstrated activation of neurotrophic and adhesion factors as well as chemokine receptors associated with inflammation. Our key find-ings on functional changes were: 1) Time and dose dependent modifications to neural output expressed as enhanced excitability but reduced synaptic efficacy and plasticity (including long term potentiation). 2) Intrinsic membrane properties of neurons were not significantly modi-fied by radiation exposure but pharmacological treatments demonstrated changes in inhibitory synapses. 3) MRI imaging visualized brain structural changes based on altered water diffu-sion properties and patterns were consistent with demyelination or gliosis. Our key findings on neurodegeneration and fidelity of homeostasis were: 1) APP23 transgenic mice exhibited accelerated APP-type electrophysiological pathology over several months. 2) Microvessel net-work changes following irradiation were suggestive of poor tissue oxygenation. 3) The ability of the brain to respond a controlled septic shock was altered by irradiation; the septic shock reactions

  1. TSH RECEPTOR GENETIC ALTERATIONS IN THE AUTONOMOUSLY FUNCTIONING THYROID ADENOMAS

    Institute of Scientific and Technical Information of China (English)

    施秉银; 李雪萍; 李社莉; 薛明战; 王毅; 徐莉

    2004-01-01

    Objective To determine the relationship between TSH receptor gene mutations and autonomously functioning thyroid adenomas (AFTAs). Methods The thyroid samples from 14 cases of diagnosed AFTAs were analyzed, with normal thyroid specimens adjacent to the tumors as controls. The 155 base pairs DNA fragments which encompassed the third cytoplasmic loop and the sixth transmembrane segments in the TSH receptor gene exon 10 were amplified by Polymerase chain reaction (PCR) and analyzed by the single-strand conformation polymorphism (SSCP). Direct sequencing of the PCR products was performed with Prism Dye Terminator Cycle Sequencing Core Kit. Results 6 of 14 AFTA specimens displayed abnormal migration in SSCP analysis. In sequence analysis of 3 abnormally migrated samples, one base substitution at nucleotide 1957 (A to C) and two same insertion mutations of one adenosine nucleotide between nucleotide 1972 and 1973 were identified. No mutations were found in controls. Conclusion This study confirmed the presence of TSH receptor gene mutations in AFTAs; both one-point substitution mutation and one-base insertion mutation were found to be responsible for the pathogenesis of AFTAs.

  2. Free p-Cresol Alters Neutrophil Function in Dogs.

    Science.gov (United States)

    Bosco, Anelise Maria; Pereira, Priscila Preve; Almeida, Breno Fernando Martins; Narciso, Luis Gustavo; Dos Santos, Diego Borba; Santos-Neto, Álvaro José Dos; Ferreira, Wagner Luis; Ciarlini, Paulo César

    2016-05-01

    To achieve a clearer understanding of the mechanisms responsible for neutrophil dysfunction recently described in dogs with chronic renal failure (CRF), the plasma concentrations of free p-cresol in healthy dogs (n = 20) and those with CRF (n = 20) were compared. The degree of correlation was determined between plasma levels of p-cresol and markers of oxidative stress and function of neutrophils in these dogs. The effect of this compound on oxidative metabolism and apoptosis was assessed in neutrophils isolated from 16 healthy dogs incubated in RPMI 1640 supplemented with p-cresol (0.405 mg/L) and compared with medium supplemented with uremic plasma (50%). To achieve this, the plasma concentration of p-cresol was quantified by liquid phase high-performance liquid chromatography. The neutrophil oxidative metabolism was determined using the probes hydroethidine and 2',7'-dichlorofluorescein diacetate and apoptosis was measured using Annexin V-PE by capillary flow cytometry. Compared with the healthy dogs, uremic dogs presented higher concentrations of free p-cresol, greater oxidative stress, and neutrophils primed for accelerated apoptosis. The free p-cresol induced in neutrophils from healthy dogs increased apoptosis and decreased reactive oxygen species production. We conclude that the health status presented during uremia concomitant with the increase in plasma free p-cresol can contribute to the presence of immunosuppression in dogs with CRF.

  3. Altered effector function of peripheral cytotoxic cells in COPD

    Directory of Open Access Journals (Sweden)

    Corne Jonathan M

    2009-06-01

    Full Text Available Abstract Background There is mounting evidence that perforin and granzymes are important mediators in the lung destruction seen in COPD. We investigated the characteristics of the three main perforin and granzyme containing peripheral cells, namely CD8+ T lymphocytes, natural killer (NK; CD56+CD3- cells and NKT-like (CD56+CD3+ cells. Methods Peripheral blood mononuclear cells (PBMCs were isolated and cell numbers and intracellular granzyme B and perforin were analysed by flow cytometry. Immunomagnetically selected CD8+ T lymphocytes, NK (CD56+CD3- and NKT-like (CD56+CD3+ cells were used in an LDH release assay to determine cytotoxicity and cytotoxic mechanisms were investigated by blocking perforin and granzyme B with relevant antibodies. Results The proportion of peripheral blood NKT-like (CD56+CD3+ cells in smokers with COPD (COPD subjects was significantly lower (0.6% than in healthy smokers (smokers (2.8%, p +CD3- cells from COPD subjects were significantly less cytotoxic than in smokers (16.8% vs 51.9% specific lysis, p +CD3+ cells (16.7% vs 52.4% specific lysis, p +CD3- and NKT-like (CD56+CD3+ cells from smokers and HNS. Conclusion In this study, we show that the relative numbers of peripheral blood NK (CD56+CD3- and NKT-like (CD56+CD3+ cells in COPD subjects are reduced and that their cytotoxic effector function is defective.

  4. Alteration in sensory nerve function following electrical shock.

    Science.gov (United States)

    Abramov, G S; Bier, M; Capelli-Schellpfeffer, M; Lee, R C

    1996-12-01

    A study of the effects of electrical shock on peripheral nerve fibres is presented. Strength and duration of the applied shocks were similar to those encountered in a typical industrial electrical accident. The purpose of this study is: (i) to identify the electrophysiological and morphological change in nerve fibres after the application of electrical current shocks; (ii) to examine the ability of the peripheral nerve fibres to spontaneously regain function and; (iii) to demonstrate the usefulness of the sensory refractory spectrum as an additional technique in assessing the damage. Three groups of animals received twelve 4-ms electric field pulses of approximately 37 V/cm (n = 5), 75 V/cm (n = 9) and 150 V/cm (n = 6), respectively. Group 4 was a control group and received a direct application of 2 per cent lidocaine over the sciatic nerve for 30 min. Thermal effects of the shocks were negligible. The sensory refractory spectrum shows that electrical shock damage was mainly to the large, fast myelinated fibres and that higher field strengths do more damage. Also in a histological examination it was found that the more heavily shocked myelinated fibres had sustained more damage.

  5. Mathematical properties of generalized Sturmian functions

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosio, M J; Punta, J A Del; Rodriguez, K V; Gasaneo, G [Departamento de Fisica, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Cientificas y Tecnicas, 8000 Bahia Blanca, Buenos Aires (Argentina); Ancarani, L U, E-mail: mja1984@gmail.com [Laboratoire de Physique Moleculaire et des Collisions, Universite Paul Verlaine-Metz, 57078 Metz (France)

    2012-01-13

    We study some mathematical properties of generalized Sturmian functions which are solutions of a Schroedinger-like equation supplemented by two boundary conditions. These generalized functions, for any value of the energy, are defined in terms of the magnitude of the potential. One of the boundary conditions is imposed at the origin of the coordinate, where regularity is required. The second point is at large distances. For negative energies, bound-like conditions are imposed. For positive or complex energies, incoming or outgoing boundary conditions are imposed to deal with scattering problems; in this case, since scattering conditions are complex, the Sturmian functions themselves are complex. Since all of the functions solve a Sturm-Liouville problem, they allow us to construct a Sturmian basis set which must be orthogonal and complete: this is the case even when they are complex. Here we study some properties of generalized Sturmian functions associated with the Hulthen potential, in particular, the spatial organization of their nodes, and demonstrate explicitly their orthogonality. We also show that the overlap matrix elements, which are generally required in scattering or bound state calculations, are well defined. Many of these mathematical properties are expressed in terms of uncommon multivariable hypergeometric functions. Finally, applications to the scattering of a particle by a Yukawa and by a Hulthen potential serve as illustrations of the efficiency of the complex Hulthen-Sturmian basis. (paper)

  6. Functional Genomics of Wood Quality and Properties

    Institute of Scientific and Technical Information of China (English)

    Wei Tang; Xiaoyan Luo; Aaron Nelson; Hilary Collver; Katherine Kinken

    2003-01-01

    Genomics promises to enrich the investigations of biology and biochemistry. Current advancements in genomics have major implications for genetic improvement in animals, plants, and microorganisms, and for our understanding of cell growth, development, differentiation, and communication. Significant progress has been made in the understanding of plant genomics in recent years, and the area continues to progress rapidly. Functional genomics offers enormous potential to tree improvement and the understanding of gene expression in this area of science worldwide.In this review we focus on functional genomics of wood quality and properties in trees, mainly based on progresses made in genomics study of Pinus and Populus.The aims of this review are to summarize the current status of functional genomics including: (1) Gene discovery; (2) EST and genomic sequencing; (3) From EST to functional genomics; (4) Approaches to functional analysis; (5) Engineering lignin biosynthesis; (6) Modification of cell wall biogenesis; and (7) Molecular modelling.Functional genomics has been greatly invested worldwide and will be important in identifying candidate genes whose function is critical to all aspects of plant growth, development, differentiation, and defense. Forest biotechnology industry will significantly benefit from the advent of functional genomics of wood quality and properties.

  7. Vital Soil: Function, Value and Properties.

    Science.gov (United States)

    This article is a review of the book, Vital Soil: Function, Value and Properties. Soil vitality has been defined as the ability of soil ecosystems to stay in balance in a changing world. The soil environment and the life that it supports developed over centuries and millennia, but careless human ac...

  8. Properties of d'Alembert functions

    DEFF Research Database (Denmark)

    Stetkær, Henrik

    We study properties of solutions of d'Alembert's functional equations on a topological group . For nilpotent groups and for connected, solvable Lie groups , we prove that has the form , , where is a continuous homomorphism of into the multiplicative group . We give conditions on and/or for equality...

  9. Altered synaptic properties during integration of adult-born hippocampal neurons following a seizure insult.

    Directory of Open Access Journals (Sweden)

    Johanna Jackson

    Full Text Available Pathological conditions affect several stages of neurogenesis in the adult brain, including proliferation, survival, cell fate, migration, and functional integration. Here we explored how a pathological environment modulates the heterogeneous afferent synaptic input that shapes the functional properties of newly formed neurons. We analyzed the expression of adhesion molecules and other synaptic proteins on adult-born hippocampal neurons formed after electrically-induced partial status epilepticus (pSE. New cells were labeled with a GFP-retroviral vector one week after pSE. One and three weeks thereafter, synaptic proteins were present on dendritic spines and shafts, but without differences between pSE and control group. In contrast, at six weeks, we found fewer dendritic spines and decreased expression of the scaffolding protein PSD-95 on spines, without changes in expression of the adhesion molecules N-cadherin or neuroligin-1, primarily located at excitatory synapses. Moreover, we detected an increased expression of the inhibitory scaffolding protein gephyrin in newborn but not mature neurons after SE. However, this increase was not accompanied by a difference in GABA expression, and there was even a region-specific decrease in the adhesion molecule neuroligin-2 expression, both in newborn and mature neurons. Neuroligin-2 clusters co-localized with presynaptic cholecystokinin terminals, which were also reduced. The expression of neuroligin-4 and glycine receptor was unchanged. Increased postsynaptic clustering of gephyrin, without an accompanying increase in GABAergic input or neuroligin-2 and -4 expression, the latter important for clustering of GABA(A and glycine receptors, respectively, could imply an increased but altered inhibitory connectivity specific for newborn neurons. The changes were transient and expression of both gephyrin and NL-2 was normalized 3 months post-SE. Our findings indicate that seizure-induced brain pathology alters

  10. Mechanical properties of functionalized carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z Q; Liu, B; Chen, Y L; Hwang, K C [FML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084 (China); Jiang, H [Department of Mechanical and Aerospace Engineering, Arizona State University, Tempe, AZ 85287 (United States); Huang, Y [Department of Civil and Environmental Engineering, Northwestern University, Evanston, IL 60208 (United States)], E-mail: liubin@tsinghua.edu.cn, E-mail: y-huang@northwestern.edu

    2008-10-01

    Carbon nanotubes (CNTs) used to reinforce polymer matrix composites are functionalized to form covalent bonds with the polymer in order to enhance the CNT/polymer interfaces. These bonds destroy the perfect atomic structures of a CNT and degrade its mechanical properties. We use atomistic simulations to study the effect of hydrogenization on the mechanical properties of single-wall carbon nanotubes. The elastic modulus of CNTs gradually decreases with the increasing functionalization (percentage of C-H bonds). However, both the strength and ductility drop sharply at a small percentage of functionalization, reflecting their sensitivity to C-H bonds. The cluster C-H bonds forming two rings leads to a significant reduction in the strength and ductility. The effect of carbonization has essentially the same effect as hydrogenization.

  11. Properties of Plasma Membrane from Pea Root Seedlings under Altered Gravity

    Science.gov (United States)

    Klymchuk, D.; Baranenko, V.; Vorobyova, T. V.; Kurylenko, I.; Chyzhykova, O.; Dubovoy, V.

    In this study, the properties of pea (Pisum sativum L.) plasma membrane were examined to determine how the membrane structure and functions are regulated in response to clinorotation (2 rev/min) conditions. Membrane preparations enriched by plasma membrane vesicles were obtained by aqueous two-phase partitioning from 6-day seedling roots. The specific characteristics of H^+-ATPase, lípid composition and peroxidation intensity as well as fluidity of lipid bilayer were analysed. ATP hydrolytic activity was inhibited by ortovanadate and was insensitive to aside and nitrate in sealed plasma membrane vesicles isolated from both clinorotated and control seedlings. Plasma membrane vesicles from clinorotated seedlings in comparison to controls were characterised by increase in the total lipid/protein ratio, ATP hydrolytic activity and intensifying of lipid peroxidation. Sitosterol and campesterol were the predominant free sterol species. Clinorotated seedlings contained a slightly higher level of unsaturated fatty acid than controls. Plasma membrane vesicles were labelled with pyrene and fluorescence originating from monomeric (I_M) molecules and excimeric (I_E) aggregates were measured. The calculated I_E/I_M values were higher in clinorotated seedlings compared with controls reflecting the reduction in membrane microviscosity. The involvement of the changes in plasma membrane lipid content and composition, fluidity and H^+-ATPase activity in response of pea seedlings to altered gravity is discussed.

  12. Alteration in cell surface properties of Burkholderia spp. during surfactant-aided biodegradation of petroleum hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, Sagarika; Mukherji, Suparna [Indian Institute of Technology Bombay, Mumbai (India). Centre for Environmental Science and Engineering (CESE)

    2012-04-15

    Chemical surfactants may impact microbial cell surface properties, i.e., cell surface hydrophobicity (CSH) and cell surface charge, and may thus affect the uptake of components from non-aqueous phase liquids (NAPLs). This work explored the impact of Triton X-100, Igepal CA 630, and Tween 80 (at twice the critical micelle concentration, CMC) on the cell surface characteristics of Burkholderia cultures, Burkholderia cepacia (ES1, aliphatic degrader) and Burkholderia multivorans (NG1, aromatic degrader), when grown on a six-component model NAPL. In the presence of Triton X-100, NAPL biodegradation was enhanced from 21% to 60% in B. cepacia and from 18% to 53% in B. multivorans. CSH based on water contact angle (50-52 ) was in the same range for both strains while zeta potential at neutral pH was -38 and -31 mV for B. cepacia and B. multivorans, respectively. In the presence of Triton X-100, their CSH increased to greater than 75 and the zeta potential decreased. This induced a change in the mode of uptake and initiated aliphatic hydrocarbon degradation by B. multivorans and increased the rate of aliphatic hydrocarbon degradation in B. cepacia. Igepal CA 630 and Tween 80 also altered the cell surface properties. For B. cepacia grown in the presence of Triton X-100 at two and five times its CMC, CSH increased significantly in the log growth phase. Growth in the presence of the chemical surfactants also affected the abundance of chemical functional groups on the cell surface. Cell surface changes had maximum impact on NAPL degradation in the presence of emulsifying surfactants, Triton X-100 and Igepal CA630.

  13. Altered cell wall properties are responsible for ammonium-reduced aluminium accumulation in rice roots.

    Science.gov (United States)

    Wang, Wei; Zhao, Xue Qiang; Chen, Rong Fu; Dong, Xiao Ying; Lan, Ping; Ma, Jian Feng; Shen, Ren Fang

    2015-07-01

    The phytotoxicity of aluminium (Al) ions can be alleviated by ammonium (NH4(+)) in rice and this effect has been attributed to the decreased Al accumulation in the roots. Here, the effects of different nitrogen forms on cell wall properties were compared in two rice cultivars differing in Al tolerance. An in vitro Al-binding assay revealed that neither NH4(+) nor NO3(-) altered the Al-binding capacity of cell walls, which were extracted from plants not previously exposed to N sources. However, cell walls extracted from NH4(+)-supplied roots displayed lower Al-binding capacity than those from NO3(-)-supplied roots when grown in non-buffered solutions. Fourier-transform infrared microspectroscopy analysis revealed that, compared with NO3(-)-supplied roots, NH4(+)-supplied roots possessed fewer Al-binding groups (-OH and COO-) and lower contents of pectin and hemicellulose. However, when grown in pH-buffered solutions, these differences in the cell wall properties were not observed. Further analysis showed that the Al-binding capacity and properties of cell walls were also altered by pHs alone. Taken together, our results indicate that the NH4(+)-reduced Al accumulation was attributed to the altered cell wall properties triggered by pH decrease due to NH4(+) uptake rather than direct competition for the cell wall binding sites between Al(3+) and NH4(+).

  14. Analytic properties of the electromagnetic Green's function

    CERN Document Server

    Gralak, Boris; Soriano, Gabriel

    2015-01-01

    A general expression of the electromagnetic Green's function is derived from the inverse Helmholtz operator, where a second frequency has been introduced as a new degree of freedom. The first frequency results from the frequency decomposition of the electromagnetic field while the second frequency is associated with the dispersion of the dielectric permittivity. Then, it is shown that the electromagnetic Green's function is analytic with respect to these two complex frequencies as soon as they have positive imaginary part. Such analytic properties are also extended to complex wavevectors. Next, Kramers-Kronig expressions for the inverse Helmholtz operator and the electromagnetic Green's function are derived. In addition, these Kramers-Kronig expressions are shown to correspond to the well-known eigengenmodes expansion of the Green's function established in simple situations. Finally, the second frequency introduced as a new degree of freedom is exploited to characterize non-dispersive systems.

  15. Structural and functional properties of designed globins

    Indian Academy of Sciences (India)

    Yasuhiro Isogai; Anna Ishii; Manabu Ishida; Masahiro Mukai; Motonori Ota; Ken Nishikawa; Tetsutaro Iizuka

    2000-06-01

    De novo design of artificial proteins is an essential approach to elucidate the principles of protein architecture and to understand specific functions of natural proteins and also to yield novel molecules for medical and industrial aims. We have designed artificial sequences of 153 amino acids to fit the main-chain framework of the sperm whale myoglobin structure based on the knowledge-based energy functions to evaluate the compatibility between protein tertiary structures and amino acid sequences. The synthesized artificial globins bind a single heme per protein molecule as designed, which show well-defined electrochemical and spectroscopic features characteristic of proteins with a low-spin heme. Redox and ligand binding reactions of the artificial heme proteins were investigated and these heme-related functions were found to vary with their structural uniqueness. Relationships between the structural and functional properties are discussed.

  16. Alteration and reorganization of functional networks: a new perspective in brain injury study

    Directory of Open Access Journals (Sweden)

    Nazareth P. Castellanos

    2011-09-01

    Full Text Available Plasticity is the mechanism underlying brain’s potential capability to compensate injury. Recently several studies have shown that functional connections among brain areas are severely altered by brain injury and plasticity leading to a reorganization of the networks. This new approach studies the impact of brain injury by means of alteration of functional interactions. The concept of functional connectivity refers to the statistical interdependencies between physiological time series simultaneously recorded in various brain areas and it could be an essential tool for brain function studies, being its deviation from healthy reference an indicator for damage. In this article, we review studies investigating functional connectivity changes after brain injury and subsequent recovery, providing an accessible introduction to common mathematical methods to infer functional connectivity, exploring their capabilities, future perspectives and clinical uses in brain injury studies.

  17. Intellectual property and regulation of functional foods

    Directory of Open Access Journals (Sweden)

    Petrović Slobodan D.

    2012-06-01

    Full Text Available Today, there exist scientific evidences that functional foods have favorable physiological and psychological effects as well as additional functions in relation to health, apart from the basic nutritional effects, thus offering the potential of enhance health or reduced the risk of diseases. Since interest in this category of foods has increased, new products have appeared as well as the need to introduce and set up standards and guidelines for the development and promotion of such foods. Technological development in this area and involvement of great multinationals in research investment and development of new products have reinforced the importance of the intellectual property rights, especially of patent protections and trademarks.

  18. AGN Host Galaxy Properties and Mass Function

    OpenAIRE

    Bongiorno, Angela

    2016-01-01

    Supermassive black hole growth, nuclear activity, and galaxy evolution have been found to be closely related. In the context of AGN-galaxy coevolution, I will discuss about the relation found between the host galaxy properties and the central BH and I will present the latest determination of the host galaxy stellar mass function (HGMF), and the specific accretion rate distribution function (SARDF), derived from the XMM-COSMOS sample up to z∼2.5, with particular focus on AGN feedback as possib...

  19. AGN Host Galaxy Properties And Mass Function

    Science.gov (United States)

    Bongiorno, Angela

    2016-10-01

    Supermassive black hole growth, nuclear activity, and galaxy evolution have been found to be closely related. In the context of AGN-galaxy coevolution, I will discuss about the relation found between the host galaxy properties and the central BH and I will present the latest determination of the host galaxy stellar mass function (HGMF), and the specific accretion rate distribution function (SARDF), derived from the XMM-COSMOS sample up to z˜2.5, with particular focus on AGN feedback as possible responsible mechanism for galaxy quenching.

  20. On AP-property of Function Spaces

    Institute of Scientific and Technical Information of China (English)

    SHEN Rong-xin

    2012-01-01

    In this paper,it is discussed the AP-property of function spaces.We prove that for any compact network α for a space X which is closed under finite unions,(1) if Cα(X) is an AP-space and X is paracompact,then X is a Hurewicz space; (2) if Cα (X) is an AP-space which has countable tightness,then Cα(X) is discretely generated.

  1. Arithmetic Properties of the Ramanujan Function

    Indian Academy of Sciences (India)

    Florian Luca; Igor E Shparlinski

    2006-02-01

    We study some arithmetic properties of the Ramanujan function (), such as the largest prime divisor ( ()) and the number of distinct prime divisors (()) of () for various sequences of . In particular, we show that ( ()) ≥ $(\\log n)^{33/31+(1)}$ for infinitely many , and $$P((p)(p^2)(p^3))>(1+(1))\\frac{\\log\\log p\\log\\log\\log p}{\\log\\log\\log\\log p}$$ for every prime with $(p)≠ 0$.

  2. Properties of Bulk Sintered Silver As a Function of Porosity

    Energy Technology Data Exchange (ETDEWEB)

    Wereszczak, Andrew A [ORNL; Vuono, Daniel J [ORNL; Wang, Hsin [ORNL; Ferber, Mattison K [ORNL; Liang, Zhenxian [ORNL

    2012-06-01

    This report summarizes a study where various properties of bulk-sintered silver were investigated over a range of porosity. This work was conducted within the National Transportation Research Center's Power Device Packaging project that is part of the DOE Vehicle Technologies Advanced Power Electronics and Electric Motors Program. Sintered silver, as an interconnect material in power electronics, inherently has porosity in its produced structure because of the way it is made. Therefore, interest existed in this study to examine if that porosity affected electrical properties, thermal properties, and mechanical properties because any dependencies could affect the intended function (e.g., thermal transfer, mechanical stress relief, etc.) or reliability of that interconnect layer and alter how its performance is modeled. Disks of bulk-sintered silver were fabricated using different starting silver pastes and different sintering conditions to promote different amounts of porosity. Test coupons were harvested out of the disks to measure electrical resistivity and electrical conductivity, thermal conductivity, coefficient of thermal expansion, elastic modulus, Poisson's ratio, and yield stress. The authors fully recognize that the microstructure of processed bulk silver coupons may indeed not be identical to the microstructure produced in thin (20-50 microns) layers of sintered silver. However, measuring these same properties with such a thin actual structure is very difficult, requires very specialized specimen preparation and unique testing instrumentation, is expensive, and has experimental shortfalls of its own, so the authors concluded that the herein measured responses using processed bulk sintered silver coupons would be sufficient to determine acceptable values of those properties. Almost all the investigated properties of bulk sintered silver changed with porosity content within a range of 3-38% porosity. Electrical resistivity, electrical conductivity

  3. Cyclic AMP stimulates neurite outgrowth of lamprey reticulospinal neurons without substantially altering their biophysical properties.

    Science.gov (United States)

    Pale, T; Frisch, E B; McClellan, A D

    2013-08-15

    Reticulospinal (RS) neurons are critical for initiation of locomotor behavior, and following spinal cord injury (SCI) in the lamprey, the axons of these neurons regenerate and restore locomotor behavior within a few weeks. For lamprey RS neurons in culture, experimental induction of calcium influx, either in the growth cone or cell body, is inhibitory for neurite outgrowth. Following SCI, these neurons partially downregulate calcium channel expression, which would be expected to reduce calcium influx and possibly provide supportive conditions for axonal regeneration. In the present study, it was tested whether activation of second messenger signaling pathways stimulates neurite outgrowth of lamprey RS neurons without altering their electrical properties (e.g. spike broadening) so as to possibly increase calcium influx and compromise axonal growth. First, activation of cAMP pathways with forskolin or dbcAMP stimulated neurite outgrowth of RS neurons in culture in a PKA-dependent manner, while activation of cGMP signaling pathways with dbcGMP inhibited outgrowth. Second, neurophysiological recordings from uninjured RS neurons in isolated lamprey brain-spinal cord preparations indicated that dbcAMP or dbcGMP did not significantly affect any of the measured electrical properties. In contrast, for uninjured RS neurons, forskolin increased action potential duration, which might have increased calcium influx, but did not significantly affect most other electrical properties. Importantly, for injured RS neurons during the period of axonal regeneration, forskolin did not significantly alter their electrical properties. Taken together, these results suggest that activation of cAMP signaling by dbcAMP stimulates neurite outgrowth, but does not alter the electrical properties of lamprey RS neurons in such a way that would be expected to induce calcium influx. In conclusion, our results suggest that activation of cAMP pathways alone, without compensation for possible

  4. Expression and structural-functional alterations of α-1-acid glycoprotein at the pathological state

    Directory of Open Access Journals (Sweden)

    Kulinich A. O.

    2010-07-01

    Full Text Available The review analyzes up-to-date knowledge on structure and biological functions of α-acid glycoprotein. The special attention is given to alterations of fucosylation, sialylation and branching of orosomucoid at the acute, chronic inflammation and oncotransformations.

  5. Effect of contractile protein alterations on cardiac myofilament function in human heart failure

    NARCIS (Netherlands)

    Narolska, N.A.

    2006-01-01

    The main objective of this thesis was to elucidate the effect of translational and post-translational alterations in contractile proteins occurring during heart failure on contractile function in human cardiac tissue. Isometric force and ATPase activity measurements were performed in skinned human

  6. Altered orbitofrontal sulcogyral patterns in adult males with high-functioning autism spectrum disorders.

    Science.gov (United States)

    Watanabe, Hiromi; Nakamura, Motoaki; Ohno, Taisei; Itahashi, Takashi; Tanaka, Eizaburo; Ohta, Haruhisa; Yamada, Takashi; Kanai, Chieko; Iwanami, Akira; Kato, Nobumasa; Hashimoto, Ryuichiro

    2014-04-01

    Functions of the orbitofrontal cortex include diverse social, cognitive and affective processes, many of which are abnormal in autism spectrum disorders (ASDs). Recently, altered orbitofrontal sulcogyral patterns have been revealed in several psychiatric conditions, such as schizophrenia, indicating a possibility that altered orbitofrontal sulcogyral morphology reflects abnormal neurodevelopment. However, the presence of sulcal alterations in ASD remains unexplored. Using structural magnetic resonance imaging, subtypes of the 'H-shaped' sulcus (Type I, II and III, in order of frequency), posterior orbital sulcus (POS) and intermediate orbital sulcus were identified in each hemisphere of adult males with ASD (n = 51) and matched normal controls (n = 55) based on the study by Chiavaras and Petrides. ASD showed a significantly altered distribution of H-shaped sulcal subtypes in both hemispheres, with a significant increase of Type III. A significant alteration in the distribution of sulcal subtypes was also identified in the right hemisphere POS of ASD. Categorical regression analysis revealed that Type I and II expressions predicted a reduced total Autism-Spectrum Quotient score. Furthermore, Type I expression was associated with a reduced 'attention to detail' subscale score. The results demonstrate that altered sulcogyral morphology can be a marker for abnormal neurodevelopment leading to the increased risk of developing autism.

  7. Formation and Functions of Alter Personalities in Dissociative Identity Disorder: A Theoretical and Clinical Elaboration

    Directory of Open Access Journals (Sweden)

    2016-12-01

    Full Text Available Dissociative identity disorder [DID] is a chronic complex psychiatric condition related to cumulative psychological traumatization in childhood. It is characterized by a marked disturbance of identity due to the presence of distinct personality states and repetitive dissociative amnesias which interfere with the continuity of the affected persons autobiography. These personality states [alter personalities] recurrently take control of or influence the individual undermining one’s sense of self and agency. Although working with alter personalities is the hallmark of psychotherapy in DID, a detailed and specific clinical and theoretical psychopathology of alter personalities do not exist yet. Hence, the present paper addresses the formation and functions of alter personalitiesin DID. The hypotheses, proposals, andassumptions developed in this paper have been derived from experiences inintensive treatment of a very large number of patients with DID over more than two decades. The authors propose that the reconciliation between diverse perspectives about one’s internal world and external reality carried by various personalities is necessary for successful treatment of DID. The hallmark of dealing with alter and host personalities constitutes of the elimination of misperceptions of themabout each other personality state and even about themselves.This requires an analysis of the missions and functions of alter personalities which are usually different thanthe perceived conceptualizations.This recognition usually increases the therapeutic alliance and even consent between the therapist, and alter and host personalities and decreases the duration of treatment. The present paper is a preliminary one on this subject and may serve as a basis both for further theoretical elaborations as well as for development of hypotheses in empirical research devoted to understanding operations of human mind when exposed to stress in particular as well as the

  8. Physically unclonable functions constructions, properties and applications

    CERN Document Server

    Maes, Roel

    2013-01-01

    Physically unclonable functions (PUFs) are innovative physical security primitives that produce unclonable and inherent instance-specific measurements of physical objects; in many ways they are the inanimate equivalent of biometrics for human beings. Since they are able to securely generate and store secrets, they allow us to bootstrap the physical implementation of an information security system. In this book the author discusses PUFs in all their facets: the multitude of their physical constructions, the algorithmic and physical properties which describe them, and the techniques required to

  9. Bilingualism alters brain functional connectivity between "control" regions and "language" regions: Evidence from bimodal bilinguals.

    Science.gov (United States)

    Li, Le; Abutalebi, Jubin; Zou, Lijuan; Yan, Xin; Liu, Lanfang; Feng, Xiaoxia; Wang, Ruiming; Guo, Taomei; Ding, Guosheng

    2015-05-01

    Previous neuroimaging studies have revealed that bilingualism induces both structural and functional neuroplasticity in the dorsal anterior cingulate cortex (dACC) and the left caudate nucleus (LCN), both of which are associated with cognitive control. Since these "control" regions should work together with other language regions during language processing, we hypothesized that bilingualism may also alter the functional interaction between the dACC/LCN and language regions. Here we tested this hypothesis by exploring the functional connectivity (FC) in bimodal bilinguals and monolinguals using functional MRI when they either performed a picture naming task with spoken language or were in resting state. We found that for bimodal bilinguals who use spoken and sign languages, the FC of the dACC with regions involved in spoken language (e.g. the left superior temporal gyrus) was stronger in performing the task, but weaker in the resting state as compared to monolinguals. For the LCN, its intrinsic FC with sign language regions including the left inferior temporo-occipital part and right inferior and superior parietal lobules was increased in the bilinguals. These results demonstrate that bilingual experience may alter the brain functional interaction between "control" regions and "language" regions. For different control regions, the FC alters in different ways. The findings also deepen our understanding of the functional roles of the dACC and LCN in language processing.

  10. Extracting spectral properties from Keldysh Green functions

    Science.gov (United States)

    Dirks, Andreas; Eckstein, Martin; Pruschke, Thomas; Werner, Philipp

    2013-02-01

    We investigate the possibility to assist the numerically ill-posed calculation of spectral properties of interacting quantum systems in thermal equilibrium by extending the imaginary-time simulation to a finite Schwinger-Keldysh contour. The effect of this extension is tested within the standard maximum entropy approach to analytic continuation. We find that the inclusion of real-time data improves the resolution of structures at high energy, while the imaginary-time data are needed to correctly reproduce low-frequency features such as quasiparticle peaks. As a nonequilibrium application, we consider the calculation of time-dependent spectral functions from retarded Green function data on a finite time interval, and compare the maximum entropy approach to direct Fourier transformation and a method based on Padé approximants.

  11. Cellulose nanocrystals: synthesis, functional properties, and applications

    Directory of Open Access Journals (Sweden)

    George J

    2015-11-01

    Full Text Available Johnsy George, SN Sabapathi Food Engineering and Packaging Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, India Abstract: Cellulose nanocrystals are unique nanomaterials derived from the most abundant and almost inexhaustible natural polymer, cellulose. These nanomaterials have received significant interest due to their mechanical, optical, chemical, and rheological properties. Cellulose nanocrystals primarily obtained from naturally occurring cellulose fibers are biodegradable and renewable in nature and hence they serve as a sustainable and environmentally friendly material for most applications. These nanocrystals are basically hydrophilic in nature; however, they can be surface functionalized to meet various challenging requirements, such as the development of high-performance nanocomposites, using hydrophobic polymer matrices. Considering the ever-increasing interdisciplinary research being carried out on cellulose nanocrystals, this review aims to collate the knowledge available about the sources, chemical structure, and physical and chemical isolation procedures, as well as describes the mechanical, optical, and rheological properties, of cellulose nanocrystals. Innovative applications in diverse fields such as biomedical engineering, material sciences, electronics, catalysis, etc, wherein these cellulose nanocrystals can be used, are highlighted. Keywords: sources of cellulose, mechanical properties, liquid crystalline nature, surface modification, nanocomposites 

  12. Alteration kinetics of a simplified nuclear glass in an aqueous medium: effects of solution chemistry and of protective gel properties on diminishing the alteration rate

    Science.gov (United States)

    Jégou, C.; Gin, S.; Larché, F.

    2000-07-01

    The alteration kinetics of the French SON 68 nuclear glass simplified to its three major constituent elements (Si, B and Na) were investigated by static experiments at 90°C in order to deconvolute the effects of the solution chemistry and of the protective properties of the alteration gel on the diminishing alteration rate over time. A glass dissolution experiment in static conditions showed that the initial rate r0 was maintained even after silicon saturation of the solution. As the reaction progressed, the glass alteration rate gradually diminished over time. These results show that the driving force behind the alteration of this glass cannot be defined by the difference from saturation with respect to amorphous silica, and that reaching saturation is not a criterion for the end of alteration. The drop in the dissolution rate observed at a high degree of reaction progress is correlated with the formation of the silica gel that develops at the glass/solution interface. Confronting the experimental data with a model taking into account a diffusion boundary layer shows that the conventional tools of chemical thermodynamics are ill adapted to describing the formation and development of the silica gel layer over time. This study reveals that only a dynamic process of hydrolysis and condensation of silicon at the glass/gel interface can account for the formation of the gel layer. The glass alteration rate under silica saturation conditions would thus be highly dependent on the silicon recondensation rate in this `dynamic percolation' concept.

  13. Nitrogen deposition alters soil chemical properties and bacterial communities in the Inner Mongolia grassland

    Institute of Scientific and Technical Information of China (English)

    Ximei Zhang; Xingguo Han

    2012-01-01

    Nitrogen deposition has dramatically altered biodiversity and ecosystem functioning on the earth; however,its effects on soil bacterial community and the underlying mechanisms of these effects have not been thoroughly examined.Changes in ecosystems caused by nitrogen deposition have traditionally been attributed to increased nitrogen content.In fact,nitrogen deposition not only leads to increased soil total N content,but also changes in the NH4+-N content,NO3--N content and pH,as well as changes in the heterogeneity of the four indexes.The soil indexes for these four factors,their heterogeneity and even the plant community might be routes through which nitrogen deposition alters the bacterial community.Here,we describe a 6-year nitrogen addition experiment conducted in a typical steppe ecosystem to investigate the ecological mechanism by which nitrogen deposition alters bacterial abundance,diversity and composition.We found that various characteristics of the bacterial community were explained by different environmental factors.Nitrogen deposition decreased bacterial abundance that is positively related to soil pH value.In addition,nitrogen addition decreased bacterial diversity,which is negatively related to soil total N content and positively related to soil NO3--N heterogeneity.Finally,nitrogen.addition altered bacterial composition that is significantly related to soil NH4+-N content.Although nitrogen deposition significantly altered plant biomass,diversity and composition,these characteristics of plant community did not have a significant impact on processes of nitrogen deposition that led to alterations in bacterial abundance,diversity and composition.Therefore,more sensitive molecular technologies should be adopted to detect the subtle shifts of microbial community structure induced by the changes of plant community upon nitrogen deposition.

  14. Alterations in renal morphology and function after ESWL therapy: evaluation with dynamic contrast-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Krestin, G.P. [Dept. of Medical Radiology, University Hospital Zurich (Switzerland); Fischbach, R. [Dept. of Radiology, Univ. of Cologne (Germany); Vorreuther, R. [Dept. of Urology, Univ. of Cologne (Germany); Schulthess, G.K. von [Dept. of Medical Radiology, University Hospital Zurich (Switzerland)

    1993-06-01

    Contrast-enhanced gradient-echo MRI was used to evaluate morphological and functional alterations in the kidneys after extracorporeal shock wave lithotripsy (ESWL). Dynamic MRI with a temporal resolution of 10 s per image was performed by repeated imaging in the coronal plane after administration of gadolinium-DTPA (0.1 mmol/kg) before and after ESWL for renal calculi in 25 patients. Before ESWL 22 patients had normally functioning kidneys, characterised by a marked decrease in signal intensity in the renal medulla 30-40 s after the onset of cortical perfusion. After ESWL 8 patients had functional abnormalities: in 2 cases the medullary signal decrease was disturbed throughout the whole organ, while 6 kidneys demonstrated regional loss of concentrating ability in the medulla. Morphological alterations (oedema with blurred contours and loss of corticomedullary differentiation; parenchymal haemorrhage and haemorrhage in a cortical cyst; subcapsular, perirenal and pararenal haematoma) were detected in 9 cases. Haemorrhage was encountered more often after administration of more than 2500 shock waves; however, no such correlation was seen in the kidneys with functional disturbances following ESWL therapy. MRI proved to be a sensitive method for the assessment of morphological and functional alterations after ESWL, but longer follow-up studies are required to identify the clinical impact of these early changes. (orig.)

  15. Functional Connectivity with the Default Mode Network Is Altered in Fibromyalgia Patients

    Science.gov (United States)

    Chiu, Yee; Nurmikko, Turo; Stancak, Andrej

    2016-01-01

    Fibromyalgia syndrome (FMS) patients show altered connectivity with the network maintaining ongoing resting brain activity, known as the default mode network (DMN). The connectivity patterns of DMN with the rest of the brain in FMS patients are poorly understood. This study employed seed-based functional connectivity analysis to investigate resting-state functional connectivity with DMN structures in FMS. Sixteen female FMS patients and 15 age-matched, healthy control subjects underwent T2-weighted resting-state MRI scanning and functional connectivity analyses using DMN network seed regions. FMS patients demonstrated alterations to connectivity between DMN structures and anterior midcingulate cortex, right parahippocampal gyrus, left superior parietal lobule and left inferior temporal gyrus. Correlation analysis showed that reduced functional connectivity between the DMN and the right parahippocampal gyrus was associated with longer duration of symptoms in FMS patients, whereas augmented connectivity between the anterior midcingulate and posterior cingulate cortices was associated with tenderness and depression scores. Our findings demonstrate alterations to functional connectivity between DMN regions and a variety of regions which are important for pain, cognitive and emotional processing in FMS patients, and which may contribute to the development or maintenance of chronic symptoms in FMS. PMID:27442504

  16. Tumor-altered dendritic cell function: implications for anti-tumor immunity

    Directory of Open Access Journals (Sweden)

    Kristian Michael Hargadon

    2013-07-01

    Full Text Available Dendritic cells are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programming of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti

  17. Genetic deletion of Mst1 alters T cell function and protects against autoimmunity.

    Directory of Open Access Journals (Sweden)

    Konstantin V Salojin

    Full Text Available Mammalian sterile 20-like kinase 1 (Mst1 is a MAPK kinase kinase kinase which is involved in a wide range of cellular responses, including apoptosis, lymphocyte adhesion and trafficking. The contribution of Mst1 to Ag-specific immune responses and autoimmunity has not been well defined. In this study, we provide evidence for the essential role of Mst1 in T cell differentiation and autoimmunity, using both genetic and pharmacologic approaches. Absence of Mst1 in mice reduced T cell proliferation and IL-2 production in vitro, blocked cell cycle progression, and elevated activation-induced cell death in Th1 cells. Mst1 deficiency led to a CD4+ T cell development path that was biased toward Th2 and immunoregulatory cytokine production with suppressed Th1 responses. In addition, Mst1-/- B cells showed decreased stimulation to B cell mitogens in vitro and deficient Ag-specific Ig production in vivo. Consistent with altered lymphocyte function, deletion of Mst1 reduced the severity of experimental autoimmune encephalomyelitis (EAE and protected against collagen-induced arthritis development. Mst1-/- CD4+ T cells displayed an intrinsic defect in their ability to respond to encephalitogenic antigens and deletion of Mst1 in the CD4+ T cell compartment was sufficient to alleviate CNS inflammation during EAE. These findings have prompted the discovery of novel compounds that are potent inhibitors of Mst1 and exhibit desirable pharmacokinetic properties. In conclusion, this report implicates Mst1 as a critical regulator of adaptive immune responses, Th1/Th2-dependent cytokine production, and as a potential therapeutic target for immune disorders.

  18. HAMLET: functional properties and therapeutic potential.

    Science.gov (United States)

    Ho C S, James; Rydström, Anna; Trulsson, Maria; Bålfors, Johannes; Storm, Petter; Puthia, Manoj; Nadeem, Aftab; Svanborg, Catharina

    2012-10-01

    Human α-lactalbumin made lethal to tumor cells (HAMLET) is the first member in a new family of protein-lipid complexes that kills tumor cells with high selectivity. The protein component of HAMLET is α-lactalbumin, which in its native state acts as a substrate specifier in the lactose synthase complex, thereby defining a function essential for the survival of lactating mammals. In addition, α-lactalbumin acquires tumoricidal activity after partial unfolding and binding to oleic acid. The lipid cofactor serves the dual role as a stabilizer of the altered fold of the protein and a coactivator of specific steps in tumor cell death. HAMLET is broadly tumoricidal, suggesting that the complex identifies conserved death pathways suitable for targeting by novel therapies. Sensitivity to HAMLET is defined by oncogene expression including Ras and c-Myc and by glycolytic enzymes. Cellular targets are located in the cytoplasmic membrane, cytoskeleton, mitochondria, proteasomes, lysosomes and nuclei, and specific signaling pathways are rapidly activated, first by interactions of HAMLET with the cell membrane and subsequently after HAMLET internalization. Therapeutic effects of HAMLET have been demonstrated in human skin papillomas and bladder cancers, and HAMLET limits the progression of human glioblastomas, with no evidence of toxicity for normal brain or bladder tissue. These findings open up new avenues for cancer therapy and the understanding of conserved death responses in tumor cells.

  19. Potential Function and Thermodynamic Property of UO

    Institute of Scientific and Technical Information of China (English)

    Xiu-lin Zeng; Si-yu Xu; Xue-hai Ju

    2013-01-01

    Potential energy scan for uranium oxide (UO) was performed by ab initio configuration interaction (CI) method and density functional theory methods at the PBE1 and the B3LYP levels in combination with the (ECP80MWB_AVQZ+2f) basis set for uranium and 6-311+G* for oxygen.The dissociation energies of UO,after being corrected for the zero-point vibrational energy,are 2.38,3.76,and 3.31 eV at the CI,PBE1,and B3LYP levels,respectively.The calculated energy was fitted to potential functions of Morse,Lennard-Jones,and Rydberg.Only the Morse function is eligible for the potential.The anharmonicity constant is 0.00425.The anharmonic frequency is 540.95 cm-1 deduced from the PBE1 results.Thermodynamic properties of entropy and heat capacity at 298.2-1500 K were calculated using DFT-UPBE1 results and Morse parameters.The relationship between entropy and temperature was established.

  20. Functional neuroanatomy of altered states of consciousness: the transient hypofrontality hypothesis.

    Science.gov (United States)

    Dietrich, Arne

    2003-06-01

    It is the central hypothesis of this paper that the mental states commonly referred to as altered states of consciousness are principally due to transient prefrontal cortex deregulation. Supportive evidence from psychological and neuroscientific studies of dreaming, endurance running, meditation, daydreaming, hypnosis, and various drug-induced states is presented and integrated. It is proposed that transient hypofrontality is the unifying feature of all altered states and that the phenomenological uniqueness of each state is the result of the differential viability of various frontal circuits. Using an evolutionary approach, consciousness is conceptualized as hierarchically ordered cognitive function. Higher-order structures perform increasingly integrative functions and thus contribute more sophisticated content. Although this implies a holistic approach to consciousness, such a functional hierarchy localizes the most sophisticated layers of consciousness in the zenithal higher-order structure: the prefrontal cortex. The hallmark of altered states of consciousness is the subtle modification of behavioral and cognitive functions that are typically ascribed to the prefrontal cortex. The theoretical framework presented yields a number of testable hypotheses.

  1. Altered mitochondrial function and energy metabolism is associated with a radioresistant phenotype in oesophageal adenocarcinoma.

    Science.gov (United States)

    Lynam-Lennon, Niamh; Maher, Stephen G; Maguire, Aoife; Phelan, James; Muldoon, Cian; Reynolds, John V; O'Sullivan, Jacintha

    2014-01-01

    Neoadjuvant chemoradiation therapy (CRT) is increasingly the standard of care for locally advanced oesophageal cancer. A complete pathological response to CRT is associated with a favourable outcome. Radiation therapy is important for local tumour control, however, radioresistance remains a substantial clinical problem. We hypothesise that alterations in mitochondrial function and energy metabolism are involved in the radioresistance of oesophageal adenocarcinoma (OAC). To investigate this, we used an established isogenic cell line model of radioresistant OAC. Radioresistant cells (OE33 R) demonstrated significantly increased levels of random mitochondrial mutations, which were coupled with alterations in mitochondrial function, size, morphology and gene expression, supporting a role for mitochondrial dysfunction in the radioresistance of this model. OE33 R cells also demonstrated altered bioenergetics, demonstrating significantly increased intracellular ATP levels, which was attributed to enhanced mitochondrial respiration. Radioresistant cells also demonstrated metabolic plasticity, efficiently switching between the glycolysis and oxidative phosphorylation energy metabolism pathways, which were accompanied by enhanced clonogenic survival. This data was supported in vivo, in pre-treatment OAC tumour tissue. Tumour ATP5B expression, a marker of oxidative phosphorylation, was significantly increased in patients who subsequently had a poor pathological response to neoadjuvant CRT. This suggests for the first time, a role for specific mitochondrial alterations and metabolic remodelling in the radioresistance of OAC.

  2. Altered mitochondrial function and energy metabolism is associated with a radioresistant phenotype in oesophageal adenocarcinoma.

    Directory of Open Access Journals (Sweden)

    Niamh Lynam-Lennon

    Full Text Available Neoadjuvant chemoradiation therapy (CRT is increasingly the standard of care for locally advanced oesophageal cancer. A complete pathological response to CRT is associated with a favourable outcome. Radiation therapy is important for local tumour control, however, radioresistance remains a substantial clinical problem. We hypothesise that alterations in mitochondrial function and energy metabolism are involved in the radioresistance of oesophageal adenocarcinoma (OAC. To investigate this, we used an established isogenic cell line model of radioresistant OAC. Radioresistant cells (OE33 R demonstrated significantly increased levels of random mitochondrial mutations, which were coupled with alterations in mitochondrial function, size, morphology and gene expression, supporting a role for mitochondrial dysfunction in the radioresistance of this model. OE33 R cells also demonstrated altered bioenergetics, demonstrating significantly increased intracellular ATP levels, which was attributed to enhanced mitochondrial respiration. Radioresistant cells also demonstrated metabolic plasticity, efficiently switching between the glycolysis and oxidative phosphorylation energy metabolism pathways, which were accompanied by enhanced clonogenic survival. This data was supported in vivo, in pre-treatment OAC tumour tissue. Tumour ATP5B expression, a marker of oxidative phosphorylation, was significantly increased in patients who subsequently had a poor pathological response to neoadjuvant CRT. This suggests for the first time, a role for specific mitochondrial alterations and metabolic remodelling in the radioresistance of OAC.

  3. Functional Properties of Grape and Wine Polyphenols.

    Science.gov (United States)

    Giovinazzo, Giovanna; Grieco, Francesco

    2015-12-01

    Grape berries polyphenols are mainly synthesized in the skin tissues and seeds and they are extracted during the winemaking process. These substances have a potentially positive effect, on human health, thus giving to grape and red wine "functional properties" that can contribute to prevent a number of human illness. Nevertheless, the research community is showing that the real effect is a result of a combination of different factors, notably daily intake, bioavailability, or in vivo antioxidant activity that are yet to be resolved. Viticulture and winemaking practices, determine the concentration of polyphenols in grape and wine. To date, reduced knowledge is existing on the effects of different yeast strains on the final concentration of polyphenols in red wine. We summarize the recent findings concerning the effects of polyphenols on human chronic disease and the future directions for research to increase the amount of these compounds in wine.

  4. Diminished A-type potassium current and altered firing properties in presympathetic PVN neurones in renovascular hypertensive rats.

    Science.gov (United States)

    Sonner, Patrick M; Filosa, Jessica A; Stern, Javier E

    2008-03-15

    Accumulating evidence supports a contribution of the hypothalamic paraventricular nucleus (PVN) to sympathoexcitation and elevated blood pressure in renovascular hypertension. However, the underlying mechanisms resulting in altered neuronal function in hypertensive rats remain largely unknown. Here, we aimed to address whether the transient outward potassium current (I(A)) in identified rostral ventrolateral medulla (RVLM)-projecting PVN neurones is altered in hypertensive rats, and whether such changes affected single and repetitive action potential properties and associated changes in intracellular Ca(2+) levels. Patch-clamp recordings obtained from PVN-RVLM neurons showed a reduction in I(A) current magnitude and single channel conductance, and an enhanced steady-state current inactivation in hypertensive rats. Morphometric reconstructions of intracellularly labelled PVN-RVLM neurons showed a diminished dendritic surface area in hypertensive rats. Consistent with a diminished I(A) availability, action potentials in PVN-RVLM neurons in hypertensive rats were broader, decayed more slowly, and were less sensitive to the K(+) channel blocker 4-aminopyridine. Simultaneous patch clamp recordings and confocal Ca(2+) imaging demonstrated enhanced action potential-evoked intracellular Ca(2+) transients in hypertensive rats. Finally, spike broadening during repetitive firing discharge was enhanced in PVN-RVLM neurons from hypertensive rats. Altogether, our results indicate that diminished I(A) availability constitutes a contributing mechanism underlying aberrant central neuronal function in renovascular hypertension.

  5. Noninvasive induction implant heating: an approach for contactless altering of mechanical properties of shape memory implants.

    Science.gov (United States)

    Pfeifer, Ronny; Hustedt, Michael; Wesling, Volker; Hurschler, Christoph; Olender, Gavin; Mach, Martin; Gösling, Thomas; Müller, Christian W

    2013-01-01

    This article shows an approach to change the properties of an orthopaedic shape memory implant within biological tissue, using contactless induction heating. Due to inducing the one way-memory effect, triggered by the rise of temperature within the implant, the geometry and hence the mechanical properties of the implant itself, are altered. The power uptake of the implant, depending on the induction parameters as well as on its position within the induction coil, is shown. Thermographic measurements are carried out in order to determine the surface temperature distribution of the implant. In order to simulate biological tissue, the implant was embedded in agarose gel. Suitable heating parameters, in terms of a short heating process in combination with a reduced heat impact on the surrounding environment, were determined.

  6. Corticotropin-releasing factor receptors and stress-related alterations of gut motor function.

    OpenAIRE

    2007-01-01

    International audience; Over the past few decades, corticotropin-releasing factor (CRF) signaling pathways have been shown to be the main coordinators of the endocrine, behavioral, and immune responses to stress. Emerging evidence also links the activation of CRF receptors type 1 and type 2 with stress-related alterations of gut motor function. Here, we review the role of CRF receptors in both the brain and the gut as part of key mechanisms through which various stressors impact propulsive ac...

  7. Investigations on Alterations of Hippocampal Circuit Function Following Mild Traumatic Brain Injury

    OpenAIRE

    2012-01-01

    Traumatic Brain Injury (TBI) afflicts more than 1.7 million people in the United States each year and even mild TBI can lead to persistent neurological impairments 1. Two pervasive and disabling symptoms experienced by TBI survivors, memory deficits and a reduction in seizure threshold, are thought to be mediated by TBI-induced hippocampal dysfunction 2,3. In order to demonstrate how altered hippocampal circuit function adversely affects behavior after TBI in mice, we employ lateral fluid per...

  8. Chronic Alcohol Ingestion in Rats Alters Lung Metabolism, Promotes Lipid Accumulation, and Impairs Alveolar Macrophage Functions

    Science.gov (United States)

    Romero, Freddy; Shah, Dilip; Duong, Michelle; Stafstrom, William; Hoek, Jan B.; Kallen, Caleb B.; Lang, Charles H.

    2014-01-01

    Chronic alcoholism impairs pulmonary immune homeostasis and predisposes to inflammatory lung diseases, including infectious pneumonia and acute respiratory distress syndrome. Although alcoholism has been shown to alter hepatic metabolism, leading to lipid accumulation, hepatitis, and, eventually, cirrhosis, the effects of alcohol on pulmonary metabolism remain largely unknown. Because both the lung and the liver actively engage in lipid synthesis, we hypothesized that chronic alcoholism would impair pulmonary metabolic homeostasis in ways similar to its effects in the liver. We reasoned that perturbations in lipid metabolism might contribute to the impaired pulmonary immunity observed in people who chronically consume alcohol. We studied the metabolic consequences of chronic alcohol consumption in rat lungs in vivo and in alveolar epithelial type II cells and alveolar macrophages (AMs) in vitro. We found that chronic alcohol ingestion significantly alters lung metabolic homeostasis, inhibiting AMP-activated protein kinase, increasing lipid synthesis, and suppressing the expression of genes essential to metabolizing fatty acids (FAs). Furthermore, we show that these metabolic alterations promoted a lung phenotype that is reminiscent of alcoholic fatty liver and is characterized by marked accumulation of triglycerides and free FAs within distal airspaces, AMs, and, to a lesser extent, alveolar epithelial type II cells. We provide evidence that the metabolic alterations in alcohol-exposed rats are mechanistically linked to immune impairments in the alcoholic lung: the elevations in FAs alter AM phenotypes and suppress both phagocytic functions and agonist-induced inflammatory responses. In summary, our work demonstrates that chronic alcohol ingestion impairs lung metabolic homeostasis and promotes pulmonary immune dysfunction. These findings suggest that therapies aimed at reversing alcohol-related metabolic alterations might be effective for preventing and

  9. Perfusion deficits and functional connectivity alterations in patients with post-traumatic stress disorder

    Science.gov (United States)

    Liu, Yang; Li, Baojuan; Zhang, Xi; Zhang, Linchuan; Li, Liang; Lu, Hongbing

    2016-03-01

    To explore the alteration in cerebral blood flow (CBF) and functional connectivity between survivors with recent onset post-traumatic stress disorder (PTSD) and without PTSD, survived from the same coal mine flood disaster. In this study, a processing pipeline using arterial spin labeling (ASL) sequence was proposed. Considering low spatial resolution of ASL sequence, a linear regression method was firstly used to correct the partial volume (PV) effect for better CBF estimation. Then the alterations of CBF between two groups were analyzed using both uncorrected and PV-corrected CBF maps. Based on altered CBF regions detected from the CBF analysis as seed regions, the functional connectivity abnormities in PTSD patients was investigated. The CBF analysis using PV-corrected maps indicates CBF deficits in the bilateral frontal lobe, right superior frontal gyrus and right corpus callosum of PTSD patients, while only right corpus callosum was identified in uncorrected CBF analysis. Furthermore, the regional CBF of the right superior frontal gyrus exhibits significantly negative correlation with the symptom severity in PTSD patients. The resting-state functional connectivity indicates increased connectivity between left frontal lobe and right parietal lobe. These results indicate that PV-corrected CBF exhibits more subtle perfusion changes and may benefit further perfusion and connectivity analysis. The symptom-specific perfusion deficits and aberrant connectivity in above memory-related regions may be putative biomarkers for recent onset PTSD induced by a single prolonged trauma exposure and help predict the severity of PTSD.

  10. Functional Overload Enhances Satellite Cell Properties in Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Shin Fujimaki

    2016-01-01

    Full Text Available Skeletal muscle represents a plentiful and accessible source of adult stem cells. Skeletal-muscle-derived stem cells, termed satellite cells, play essential roles in postnatal growth, maintenance, repair, and regeneration of skeletal muscle. Although it is well known that the number of satellite cells increases following physical exercise, functional alterations in satellite cells such as proliferative capacity and differentiation efficiency following exercise and their molecular mechanisms remain unclear. Here, we found that functional overload, which is widely used to model resistance exercise, causes skeletal muscle hypertrophy and converts satellite cells from quiescent state to activated state. Our analysis showed that functional overload induces the expression of MyoD in satellite cells and enhances the proliferative capacity and differentiation potential of these cells. The changes in satellite cell properties coincided with the inactivation of Notch signaling and the activation of Wnt signaling and likely involve modulation by transcription factors of the Sox family. These results indicate the effects of resistance exercise on the regulation of satellite cells and provide insight into the molecular mechanism of satellite cell activation following physical exercise.

  11. Alteration of long-distance functional connectivity and network topology in patients with supratentorial gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Eun; Kim, Ho Sung; Kim, Sang Joon; Shim, Woo Hyun [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Songpa-Gu, Seoul (Korea, Republic of); Kim, Jeong Hoon [University of Ulsan College of Medicine, Department of Neurosurgery, Asan Medical Center, Seoul (Korea, Republic of)

    2016-03-15

    The need for information regarding functional alterations in patients with brain gliomas is increasing, but little is known about the functional consequences of focal brain tumors throughout the entire brain. Using resting-state functional MR imaging (rs-fMRI), this study assessed functional connectivity in patients with supratentorial brain gliomas with possible alterations in long-distance connectivity and network topology. Data from 36 patients with supratentorial brain gliomas and 12 healthy subjects were acquired using rs-fMRI. The functional connectivity matrix (FCM) was created using 32 pairs of cortical seeds on Talairach coordinates in each individual subject. Local and distant connectivity were calculated using z-scores in the individual patient's FCM, and the averaged FCM of patients was compared with that of healthy subjects. Weighted network analysis was performed by calculating local efficiency, global efficiency, clustering coefficient, and small-world topology, and compared between patients and healthy controls. When comparing the averaged FCM of patients with that of healthy controls, the patients showed decreased long-distance, inter-hemispheric connectivity (0.32 ± 0.16 in patients vs. 0. 42 ± 0.15 in healthy controls, p = 0.04). In network analysis, patients showed increased local efficiency (p < 0.05), but global efficiency, clustering coefficient, and small-world topology were relatively preserved compared to healthy subjects. Patients with supratentorial brain gliomas showed decreased long-distance connectivity while increased local efficiency and preserved small-world topology. The results of this small case series may provide a better understanding of the alterations of functional connectivity in patients with brain gliomas across the whole brain scale. (orig.)

  12. Study of Fixed Point Theorem for Common Limit Range Property and Application to Functional Equations

    Directory of Open Access Journals (Sweden)

    Nashine Hemant Kumar

    2014-06-01

    Full Text Available The aim of our paper is to use common limit range property for two pairs of mappings deriving common fixed point results under a generalized altering distance function. Some examples are given to exhibit different type of situation which shows the requirements of conditions of our results. At the end the existence and uniqueness of solutions for certain system of functional equations arising in dynamic programming with the help of a common fixed point theorem is presented.

  13. Surviving endoplasmic reticulum stress is coupled to altered chondrocyte differentiation and function.

    Directory of Open Access Journals (Sweden)

    Kwok Yeung Tsang

    2007-03-01

    Full Text Available In protein folding and secretion disorders, activation of endoplasmic reticulum (ER stress signaling (ERSS protects cells, alleviating stress that would otherwise trigger apoptosis. Whether the stress-surviving cells resume normal function is not known. We studied the in vivo impact of ER stress in terminally differentiating hypertrophic chondrocytes (HCs during endochondral bone formation. In transgenic mice expressing mutant collagen X as a consequence of a 13-base pair deletion in Col10a1 (13del, misfolded alpha1(X chains accumulate in HCs and elicit ERSS. Histological and gene expression analyses showed that these chondrocytes survived ER stress, but terminal differentiation is interrupted, and endochondral bone formation is delayed, producing a chondrodysplasia phenotype. This altered differentiation involves cell-cycle re-entry, the re-expression of genes characteristic of a prehypertrophic-like state, and is cell-autonomous. Concomitantly, expression of Col10a1 and 13del mRNAs are reduced, and ER stress is alleviated. ERSS, abnormal chondrocyte differentiation, and altered growth plate architecture also occur in mice expressing mutant collagen II and aggrecan. Alteration of the differentiation program in chondrocytes expressing unfolded or misfolded proteins may be part of an adaptive response that facilitates survival and recovery from the ensuing ER stress. However, the altered differentiation disrupts the highly coordinated events of endochondral ossification culminating in chondrodysplasia.

  14. Preacclimation alters Salmonella Enteritidis surface properties and its initial attachment to food contact surfaces.

    Science.gov (United States)

    Yang, Yishan; Kumar, Amit; Zheng, Qianwang; Yuk, Hyun-Gyun

    2015-04-01

    Exposure of Salmonella to environmental stress, prior to its adherence to a food contact surface, may change the cell surface properties and consequently affect its initial attachment and biofilm formation. This study investigated the influence of temperature and pH preacclimation on the initial attachment of Salmonella Enteritidis to acrylic and stainless steel. Besides, changes in physicochemical properties of cells were examined; and their surface attachment was modeled by xDLVO theory. Results showed that control cells pre-grown at 37°C had significantly (P0.05) different from control cells pre-grown at pH 7.3, but they were significantly higher compared to cells pre-grown at pH 8.3 and 9.0. No significant difference was observed between cell attachment to acrylic and stainless steel, although they had different physicochemical properties. The xDLVO theory successfully explained higher attachment for cells pre-grown at optimal condition on both contact surfaces. However, the xDLVO theory could not explain the similar attachment of cells to acrylic and stainless steel. This study elucidates that commonly used intervention technologies including cold storage, thermal treatment, and alkaline antimicrobial agents might alter the physicochemical properties of S. Enteritidis cells and result in varied initial attachment levels.

  15. Convergent Findings of Altered Functional and Structural Brain Connectivity in Individuals with High Functioning Autism: A Multimodal MRI Study.

    Science.gov (United States)

    Mueller, Sophia; Keeser, Daniel; Samson, Andrea C; Kirsch, Valerie; Blautzik, Janusch; Grothe, Michel; Erat, Okan; Hegenloh, Michael; Coates, Ute; Reiser, Maximilian F; Hennig-Fast, Kristina; Meindl, Thomas

    2013-01-01

    Brain tissue changes in autism spectrum disorders seem to be rather subtle and widespread than anatomically distinct. Therefore a multimodal, whole brain imaging technique appears to be an appropriate approach to investigate whether alterations in white and gray matter integrity relate to consistent changes in functional resting state connectivity in individuals with high functioning autism (HFA). We applied diffusion tensor imaging (DTI), voxel-based morphometry (VBM) and resting state functional connectivity magnetic resonance imaging (fcMRI) to assess differences in brain structure and function between 12 individuals with HFA (mean age 35.5, SD 11.4, 9 male) and 12 healthy controls (mean age 33.3, SD 9.0, 8 male). Psychological measures of empathy and emotionality were obtained and correlated with the most significant DTI, VBM and fcMRI findings. We found three regions of convergent structural and functional differences between HFA participants and controls. The right temporo-parietal junction area and the left frontal lobe showed decreased fractional anisotropy (FA) values along with decreased functional connectivity and a trend towards decreased gray matter volume. The bilateral superior temporal gyrus displayed significantly decreased functional connectivity that was accompanied by the strongest trend of gray matter volume decrease in the temporal lobe of HFA individuals. FA decrease in the right temporo-parietal region was correlated with psychological measurements of decreased emotionality. In conclusion, our results indicate common sites of structural and functional alterations in higher order association cortex areas and may therefore provide multimodal imaging support to the long-standing hypothesis of autism as a disorder of impaired higher-order multisensory integration.

  16. Convergent Findings of Altered Functional and Structural Brain Connectivity in Individuals with High Functioning Autism: A Multimodal MRI Study.

    Directory of Open Access Journals (Sweden)

    Sophia Mueller

    Full Text Available Brain tissue changes in autism spectrum disorders seem to be rather subtle and widespread than anatomically distinct. Therefore a multimodal, whole brain imaging technique appears to be an appropriate approach to investigate whether alterations in white and gray matter integrity relate to consistent changes in functional resting state connectivity in individuals with high functioning autism (HFA. We applied diffusion tensor imaging (DTI, voxel-based morphometry (VBM and resting state functional connectivity magnetic resonance imaging (fcMRI to assess differences in brain structure and function between 12 individuals with HFA (mean age 35.5, SD 11.4, 9 male and 12 healthy controls (mean age 33.3, SD 9.0, 8 male. Psychological measures of empathy and emotionality were obtained and correlated with the most significant DTI, VBM and fcMRI findings. We found three regions of convergent structural and functional differences between HFA participants and controls. The right temporo-parietal junction area and the left frontal lobe showed decreased fractional anisotropy (FA values along with decreased functional connectivity and a trend towards decreased gray matter volume. The bilateral superior temporal gyrus displayed significantly decreased functional connectivity that was accompanied by the strongest trend of gray matter volume decrease in the temporal lobe of HFA individuals. FA decrease in the right temporo-parietal region was correlated with psychological measurements of decreased emotionality. In conclusion, our results indicate common sites of structural and functional alterations in higher order association cortex areas and may therefore provide multimodal imaging support to the long-standing hypothesis of autism as a disorder of impaired higher-order multisensory integration.

  17. Venom of the Chilean Latrodectus mactans alters bovine spermatozoa calcium and function by blocking the TEA-sensitive K(+) current.

    Science.gov (United States)

    Navarrete, Patricia; Martínez-Torres, Ataúlfo; Gutiérrez, Raúl Sánchez; Mejía, Fernando Romero; Parodi, Jorge

    2010-08-01

    The morphology and size of spermatozoa make it difficult to study the functional properties of the plasma membrane, however, some studies have revealed the presence of a number of ion channels in this cell. We measured the calcium (Ca(++)) influx induced by depolarization of the plasma membrane and by venom isolated from the Chilean black widow spider (Latrodectus mactans), and functional changes in the presence of either high potassium or total venom. Our results indicate that the venom increased the Ca(++) influx, with an EC50 of 6.1 microg/mL and triggering the acrosome reaction in 43.26% of the cells. The application of potassium (10 mM K(+)) or total venom (10 microg/mL) did not affect the morphology or DNA stability of the sperm. The effects induced by high K(+) and venom suggest that direct blocking of K(+) currents alters the passive properties of the plasma membrane, leading to the entry of Ca(++). These results show the importance of functional changes induced by depolarizing the spermatozoa and by venom. This venom possesses one or more molecules that may be used as pharmacological tools for studies on spermatozoa and have potential applications in reproductive biotechnology.

  18. Dynamic functional connectivity reveals altered variability in functional connectivity among patients with major depressive disorder

    Science.gov (United States)

    Tornador, Cristian; Falcón, Carles; López‐Solà, Marina; Hernández‐Ribas, Rosa; Pujol, Jesús; Menchón, José M.; Ritter, Petra; Cardoner, Narcis; Soriano‐Mas, Carles; Deco, Gustavo

    2016-01-01

    Abstract Resting‐state fMRI (RS‐fMRI) has become a useful tool to investigate the connectivity structure of mental health disorders. In the case of major depressive disorder (MDD), recent studies regarding the RS‐fMRI have found abnormal connectivity in several regions of the brain, particularly in the default mode network (DMN). Thus, the relevance of the DMN to self‐referential thoughts and ruminations has made the use of the resting‐state approach particularly important for MDD. The majority of such research has relied on the grand averaged functional connectivity measures based on the temporal correlations between the BOLD time series of various brain regions. We, in our study, investigated the variations in the functional connectivity over time at global and local level using RS‐fMRI BOLD time series of 27 MDD patients and 27 healthy control subjects. We found that global synchronization and temporal stability were significantly increased in the MDD patients. Furthermore, the participants with MDD showed significantly increased overall average (static) functional connectivity (sFC) but decreased variability of functional connectivity (vFC) within specific networks. Static FC increased to predominance among the regions pertaining to the default mode network (DMN), while the decreased variability of FC was observed in the connections between the DMN and the frontoparietal network. Hum Brain Mapp 37:2918–2930, 2016. © 2016 Wiley Periodicals, Inc. PMID:27120982

  19. Role of CRF in stress-related alterations of gastric and colonic motor function.

    Science.gov (United States)

    Taché, Y; Mönnikes, H; Bonaz, B; Rivier, J

    1993-10-29

    Major advances have been made in the understanding of the pathophysiology of stress-related alteration of gut function. A wealth of information indicates that CRF is involved in the central mechanisms by which stress inhibits gastric emptying while stimulating colonic motor function. CRF acts in the PVN to trigger both the inhibition of gastric emptying and the stimulation of colonic motor function in response to stress, in addition to previously established endocrine and behavioral responses. Preliminary evidence exists that CRF acts in the locus coeruleus to induce a selective stimulation of colonic transit without influencing gastric emptying. The central actions of CRF to alter gastric and colonic motor function are conveyed by autonomic pathways and are unrelated to the associated stimulation of pituitary hormone secretion. The demonstration that central CRF plays a role in mediating gastric stasis resulting from surgery, peritonitis or high levels of central interleukin-1 provides new insight into the mechanisms involved in gastric ileus induced postoperatively or by infectious disease. Likewise, the demonstration that CRF in the PVN and locus coeruleus induce the anxiogenic and colonic motor responses to stress and that colonic distention activates neurons in the locus coeruleus opens new avenues for the understanding of the pathogenesis of a subset of IBS patients with colonic hypersensitivity associated with psychopathological disturbance and diarrhea-predominant symptoms.

  20. Invasion by the Alien Tree Prunus serotina Alters Ecosystem Functions in a Temperate Deciduous Forest.

    Science.gov (United States)

    Aerts, Raf; Ewald, Michael; Nicolas, Manuel; Piat, Jérôme; Skowronek, Sandra; Lenoir, Jonathan; Hattab, Tarek; Garzón-López, Carol X; Feilhauer, Hannes; Schmidtlein, Sebastian; Rocchini, Duccio; Decocq, Guillaume; Somers, Ben; Van De Kerchove, Ruben; Denef, Karolien; Honnay, Olivier

    2017-01-01

    Alien invasive species can affect large areas, often with wide-ranging impacts on ecosystem structure, function, and services. Prunus serotina is a widespread invader of European temperate forests, where it tends to form homogeneous stands and limits recruitment of indigenous trees. We hypotesized that invasion by P. serotina would be reflected in the nutrient contents of the native species' leaves and in the respiration of invaded plots as efficient resource uptake and changes in nutrient cycling by P. serotina probably underly its aggressive invasiveness. We combined data from 48 field plots in the forest of Compiègne, France, and data from an experiment using 96 microcosms derived from those field plots. We used general linear models to separate effects of invasion by P. serotina on heterotrophic soil and litter respiration rates and on canopy foliar nutrient content from effects of soil chemical properties, litter quantity, litter species composition, and tree species composition. In invaded stands, average respiration rates were 5.6% higher for soil (without litter) and 32% higher for soil and litter combined. Compared to indigenous tree species, P. serotina exhibited higher foliar N (+24.0%), foliar P (+50.7%), and lower foliar C:N (-22.4%) and N:P (-10.1%) ratios. P. serotina affected foliar nutrient contents of co-occuring indigenous tree species leading to decreased foliar N (-8.7 %) and increased C:N ratio (+9.5%) in Fagus sylvatica, decreased foliar N:P ratio in Carpinus betulus (-13.5%) and F. sylvatica (-11.8%), and increased foliar P in Pinus sylvestris (+12.3%) in invaded vs. uninvaded stands. Our results suggest that P. serotina is changing nitrogen, phosphorus, and carbon cycles to its own advantage, hereby increasing carbon turnover via labile litter, affecting the relative nutrient contents in the overstory leaves, and potentially altering the photosynthetic capacity of the long-lived indigenous broadleaved species. Uncontrolled invasion of

  1. Dietary inulin alters the intestinal absorptive and barrier function of piglet intestine after weaning.

    Science.gov (United States)

    Awad, Wageha A; Ghareeb, Khaled; Paßlack, Nadine; Zentek, Jürgen

    2013-08-01

    An experiment was conducted to study the effects of dietary inulin supplementation on the electrophysiological properties of small intestine of suckling and weaned piglets as indicators for glucose absorption and barrier function. Ten sows were divided into two groups, receiving either a control diet, or a diet with 3% inulin. The diets were fed from 3 weeks ante partum to 6 weeks post partum. In the first 2 weeks of life, piglets received only sow's milk. Irrespective to sex and without castration of males, four piglets (one piglet of each litter) from each group were selected and sacrificed on day 10 of age. The gastrointestinal tract of each piglet was removed and segments were immediately taken from the mid-jejunum and mounted in Ussing chambers. Furthermore, at weaning (6 weeks old) 8 piglets were randomly selected irrespective to sex and males were un-castrated (4 animals from sows received control diet and 4 animals from sows received 3% inulin supplemented diet) and fed for 2 weeks either control weaning diet or inulin supplemented diet. Thereafter segments of the mid-jejunum were used to investigate the effect of inulin on the gut electrophysiology of weaned piglets. The increase in short-circuit current (Isc) after the addition of glucose is an indicator of higher glucose absorption and the higher tissue conductance (Gt) of the epithelium suggested a higher intestinal permeability to paracellular Na(+). In suckling piglets, the addition of d-glucose on the luminal side of the isolated jejunal mucosa increased (P<0.001) the Isc in the inulin-supplemented and control groups compared to basal values. Electrogenic glucose transport (ΔIsc) was similar in suckling piglets from sows fed inulin or control diet, suggesting that feeding of inulin to the mother sows had no effect on glucose absorption across the jejunal mucosa of suckling piglets. However, the dietary inulin supplementation after weaning increased the ΔIsc (P<0.001) compared with the controls

  2. Invasion by the Alien Tree Prunus serotina Alters Ecosystem Functions in a Temperate Deciduous Forest

    Science.gov (United States)

    Aerts, Raf; Ewald, Michael; Nicolas, Manuel; Piat, Jérôme; Skowronek, Sandra; Lenoir, Jonathan; Hattab, Tarek; Garzón-López, Carol X.; Feilhauer, Hannes; Schmidtlein, Sebastian; Rocchini, Duccio; Decocq, Guillaume; Somers, Ben; Van De Kerchove, Ruben; Denef, Karolien; Honnay, Olivier

    2017-01-01

    Alien invasive species can affect large areas, often with wide-ranging impacts on ecosystem structure, function, and services. Prunus serotina is a widespread invader of European temperate forests, where it tends to form homogeneous stands and limits recruitment of indigenous trees. We hypotesized that invasion by P. serotina would be reflected in the nutrient contents of the native species' leaves and in the respiration of invaded plots as efficient resource uptake and changes in nutrient cycling by P. serotina probably underly its aggressive invasiveness. We combined data from 48 field plots in the forest of Compiègne, France, and data from an experiment using 96 microcosms derived from those field plots. We used general linear models to separate effects of invasion by P. serotina on heterotrophic soil and litter respiration rates and on canopy foliar nutrient content from effects of soil chemical properties, litter quantity, litter species composition, and tree species composition. In invaded stands, average respiration rates were 5.6% higher for soil (without litter) and 32% higher for soil and litter combined. Compared to indigenous tree species, P. serotina exhibited higher foliar N (+24.0%), foliar P (+50.7%), and lower foliar C:N (−22.4%) and N:P (−10.1%) ratios. P. serotina affected foliar nutrient contents of co-occuring indigenous tree species leading to decreased foliar N (−8.7 %) and increased C:N ratio (+9.5%) in Fagus sylvatica, decreased foliar N:P ratio in Carpinus betulus (−13.5%) and F. sylvatica (−11.8%), and increased foliar P in Pinus sylvestris (+12.3%) in invaded vs. uninvaded stands. Our results suggest that P. serotina is changing nitrogen, phosphorus, and carbon cycles to its own advantage, hereby increasing carbon turnover via labile litter, affecting the relative nutrient contents in the overstory leaves, and potentially altering the photosynthetic capacity of the long-lived indigenous broadleaved species. Uncontrolled

  3. Wetlands - different types, their properties and functions

    Energy Technology Data Exchange (ETDEWEB)

    Kellner, Erik [Uppsala Univ. (Sweden). Dept. of Earth Sciences/Hydrology

    2003-08-01

    In this report, different Swedish wetland types are presented with emphasis on their occurrence, vegetation cover, soil physical and chemical properties and functions. Three different main groups of wetlands are identified: bogs, fens and marshes. The former two are peat forming environments while the term 'marshes' covers all non-peat forming wetlands. Poor fens are the most common type in Sweden but (tree-covered) marshes would probably be dominating large areas in Southern Sweden if not affected by human activity such as drainage for farming. Fens and bogs are often coexisting next to each other and bogs are often seen to be the next step after fens in the natural succession. However, the development of wetlands and processes of succession between different wetland types are resulting from complicated interactions between climate, vegetation, geology and topography. For description of the development at individual sites, the hydrological settings which determine the water flow paths seem to be most crucial, emphasizing the importance of geology and topography. For modelling the growth of peat, simple models have so far dominated, but these are often restricted in general use. Therefore, more physical-based models have been developed, but the natural heterogeneity and climate shifts bring uncertainty of how they should be parameterised. The use of coupled groundwater-substance transport models have shown to help understand how water flows and soil chemistry are developing in response to different peat forms. The peat is characterised by a high porosity (80-95%) which is decreasing with decomposition and depth. The most important change is then that the actively conducting pores are getting clogged and closed. The storage coefficient of the peat is then decreasing with decomposition as well as the hydraulic conductivity. The variation of hydraulic conductivity (k) can be large and current understanding of the connections between hydraulic conductivity

  4. Functional Alterations in Neural Substrates of Geometric Reasoning in Adults with High-Functioning Autism

    OpenAIRE

    Takashi Yamada; Haruhisa Ohta; Hiromi Watanabe; Chieko Kanai; Masayuki Tani; Taisei Ohno; Yuko Takayama; Akira Iwanami; Nobumasa Kato; Ryuichiro Hashimoto

    2012-01-01

    Individuals with autism spectrum condition (ASC) are known to excel in some perceptual cognitive tasks, but such developed functions have been often regarded as "islets of abilities" that do not significantly contribute to broader intellectual capacities. However, recent behavioral studies have reported that individuals with ASC have advantages for performing Raven's (Standard) Progressive Matrices (RPM/RSPM), a standard neuropsychological test for general fluid intelligence, raising the poss...

  5. Using deposition rate as a means to alter the properties of small molecule organic glasses for OLED applications

    Science.gov (United States)

    Kearns, Kenneth; Krzyskowski, Paige; Devereaux, Zachary

    2015-03-01

    Organic light emitting diode (OLED) devices rely on vapor-deposited, small molecule organic glasses. Recent work has shown that deposition condition plays a critical role in altering OLED device performance. Here it will be shown that the deposition rate alters the onset and fictive temperatures measured by differential scanning calorimetry (DSC) of the deposited glass. Glasses of the common hole transport materials NPD and TPD were prepared with onset temperatures 17 and 16 K higher, respectively, than the ordinary glass prepared by cooling the supercooled liquid. The thermal stability of glasses in functioning devices can be underestimated due to increases in onset temperature relative to Tg. The fictive temperatures for NPD and TPD were 32 and 27 K lower, respectively, than the Tg of the ordinary glass. These results are consistent with literature reports on other non-OLED glasses where enhanced surface mobility allowed for glasses with similar properties to be made. Ellipsometry studies on NPD showed that the fictive and onset temperatures were consistent with the DSC results. Additionally, the modeled birefringence of the as-deposited NPD glass was non-zero and quickly decreased upon heating above the onset temperature, which has implications for device performance. Formerly at Department of Chemistry, Saginaw Valley State University.

  6. HDL-S1P: cardiovascular functions, disease-associated alterations, and therapeutic applications.

    Science.gov (United States)

    Levkau, Bodo

    2015-01-01

    Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid contained in High-density lipoproteins (HDL) and has drawn considerable attention in the lipoprotein field as numerous studies have demonstrated its contribution to several functions inherent to HDL. Some of them are partly and some entirely due to the S1P contained in HDL (HDL-S1P). Despite the presence of over 1000 different lipids in HDL, S1P stands out as it possesses its own cell surface receptors through which it exercises key physiological functions. Most of the S1P in human plasma is associated with HDL, and the amount of HDL-S1P influences the quality and quantity of HDL-dependent functions. The main binding partner of S1P in HDL is apolipoprotein M but others may also exist particularly under conditions of acute S1P elevations. HDL not only exercise functions through their S1P content but have also an impact on genuine S1P signaling by influencing S1P bioactivity and receptor presentation. HDL-S1P content is altered in human diseases such as atherosclerosis, coronary artery disease, myocardial infarction, renal insufficiency and diabetes mellitus. Low HDL-S1P has also been linked to impaired HDL functions associated with these disorders. Although the pathophysiological and molecular reasons for such disease-associated shifts in HDL-S1P are little understood, there have been successful approaches to circumvent their adverse implications by pharmacologically increasing HDL-S1P as means to improve HDL function. This mini-review will cover the current understanding of the contribution of HDL-S1P to physiological HDL function, its alteration in disease and ways for its restoration to correct HDL dysfunction.

  7. Myocardial Perfusion and Function Are Distinctly Altered by Sevoflurane Anesthesia in Diet-Induced Prediabetic Rats

    Directory of Open Access Journals (Sweden)

    Charissa E. van den Brom

    2016-01-01

    Full Text Available Preservation of myocardial perfusion during surgery is particularly important in patients with increased risk for perioperative complications, such as diabetes. Volatile anesthetics, like sevoflurane, have cardiodepressive effects and may aggravate cardiovascular complications. We investigated the effect of sevoflurane on myocardial perfusion and function in prediabetic rats. Rats were fed a western diet (WD; n=18 or control diet (CD; n=18 for 8 weeks and underwent (contrast echocardiography to determine perfusion and function during baseline and sevoflurane exposure. Myocardial perfusion was estimated based on the product of microvascular filling velocity and blood volume. WD-feeding resulted in a prediabetic phenotype characterized by obesity, hyperinsulinemia, hyperlipidemia, glucose intolerance, and hyperglycemia. At baseline, WD-feeding impaired myocardial perfusion and systolic function compared to CD-feeding. Exposure of healthy rats to sevoflurane increased the microvascular filling velocity without altering myocardial perfusion but impaired systolic function. In prediabetic rats, sevoflurane did also not affect myocardial perfusion; however, it further impaired systolic function. Diet-induced prediabetes is associated with impaired myocardial perfusion and function in rats. While sevoflurane further impaired systolic function, it did not affect myocardial perfusion in prediabetic rats. Our findings suggest that sevoflurane anesthesia leads to uncoupling of myocardial perfusion and function, irrespective of the metabolic state.

  8. Myocardial Perfusion and Function Are Distinctly Altered by Sevoflurane Anesthesia in Diet-Induced Prediabetic Rats.

    Science.gov (United States)

    van den Brom, Charissa E; Boly, Chantal A; Bulte, Carolien S E; van den Akker, Rob F P; Kwekkeboom, Rick F J; Loer, Stephan A; Boer, Christa; Bouwman, R Arthur

    2016-01-01

    Preservation of myocardial perfusion during surgery is particularly important in patients with increased risk for perioperative complications, such as diabetes. Volatile anesthetics, like sevoflurane, have cardiodepressive effects and may aggravate cardiovascular complications. We investigated the effect of sevoflurane on myocardial perfusion and function in prediabetic rats. Rats were fed a western diet (WD; n = 18) or control diet (CD; n = 18) for 8 weeks and underwent (contrast) echocardiography to determine perfusion and function during baseline and sevoflurane exposure. Myocardial perfusion was estimated based on the product of microvascular filling velocity and blood volume. WD-feeding resulted in a prediabetic phenotype characterized by obesity, hyperinsulinemia, hyperlipidemia, glucose intolerance, and hyperglycemia. At baseline, WD-feeding impaired myocardial perfusion and systolic function compared to CD-feeding. Exposure of healthy rats to sevoflurane increased the microvascular filling velocity without altering myocardial perfusion but impaired systolic function. In prediabetic rats, sevoflurane did also not affect myocardial perfusion; however, it further impaired systolic function. Diet-induced prediabetes is associated with impaired myocardial perfusion and function in rats. While sevoflurane further impaired systolic function, it did not affect myocardial perfusion in prediabetic rats. Our findings suggest that sevoflurane anesthesia leads to uncoupling of myocardial perfusion and function, irrespective of the metabolic state.

  9. Mutations in ionotropic AMPA receptor 3 alter channel properties and are associated with moderate cognitive impairment in humans.

    Science.gov (United States)

    Wu, Ye; Arai, Amy C; Rumbaugh, Gavin; Srivastava, Anand K; Turner, Gillian; Hayashi, Takashi; Suzuki, Erika; Jiang, Yuwu; Zhang, Lilei; Rodriguez, Jayson; Boyle, Jackie; Tarpey, Patrick; Raymond, F Lucy; Nevelsteen, Joke; Froyen, Guy; Stratton, Mike; Futreal, Andy; Gecz, Jozef; Stevenson, Roger; Schwartz, Charles E; Valle, David; Huganir, Richard L; Wang, Tao

    2007-11-13

    Ionotropic alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors (iGluRs) mediate the majority of excitatory synaptic transmission in the CNS and are essential for the induction and maintenance of long-term potentiation and long-term depression, two cellular models of learning and memory. We identified a genomic deletion (0.4 Mb) involving the entire GRIA3 (encoding iGluR3) by using an X-array comparative genomic hybridization (CGH) and four missense variants (G833R, M706T, R631S, and R450Q) in functional domains of iGluR3 by sequencing 400 males with X-linked mental retardation (XLMR). Three variants were found in males with moderate MR and were absent in 500 control males. Expression studies in HEK293 cells showed that G833R resulted in a 78% reduction of iGluR3 due to protein misfolding. Whole-cell recording studies of iGluR3 homomers in HEK293 cells revealed that neither iGluR3-M706T (S2 domain) nor iGluR3-R631S (near channel core) had substantial channel function, whereas R450Q (S1 domain) was associated with accelerated receptor desensitization. When forming heteromeric receptors with iGluR2 in HEK293 cells, all four iGluR3 variants had altered desensitization kinetics. Our study provides the genetic and functional evidence that mutant iGluR3 with altered kinetic properties is associated with moderate cognitive impairment in humans.

  10. The anabolic steroid nandrolone alters cannabinoid self-administration and brain CB1 receptor density and function.

    Science.gov (United States)

    Struik, Dicky; Fadda, Paola; Zara, Tamara; Zamberletti, Erica; Rubino, Tiziana; Parolaro, Daniela; Fratta, Walter; Fattore, Liana

    2017-01-01

    Clinical and pre-clinical observations indicate that anabolic-androgenic steroids can induce neurobiological changes that alter the rewarding effects of drugs of abuse. In this study, we investigated the effect of the anabolic steroid nandrolone on the rewarding properties of the cannabinoid CB1 receptor agonist WIN55,212-2 (WIN) in rats. Lister Hooded male rats were treated intramuscularly with nandrolone (15mg/kg) or vehicle for 14 consecutive days, and then allowed to self-administer WIN (12.5μg/kg/infusion) intravenously. After reaching stable drug intake, self-administration behavior was extinguished to examine drug- and cue-induced reinstatement of cannabinoid-seeking behavior. Other behavioral parameters presumed to influence drug-taking and drug-seeking behaviors were examined to gain more insight into the behavioral specificity of nandrolone treatment. Finally, animals were sacrificed for analysis of CB1 receptor density and function in selected brain areas. We found that nandrolone-treated rats self-administered up to 2 times more cannabinoid than vehicle-treated rats, but behaved similarly to control rats when tested for drug- and cue-induced reinstatement of cannabinoid-seeking behavior. Enhanced cannabinoid intake by nandrolone-treated rats was not accompanied by changes in locomotor activity, sensorimotor gating, or memory function. However, our molecular data show that after chronic WIN self-administration nandrolone-treated rats display altered CB1 receptor density and function in selected brain areas. We hypothesize that increased cannabinoid self-administration in nandrolone-treated rats results from a nandrolone-induced decrease in reward function, which rats seem to compensate by voluntarily increasing their cannabinoid intake. Altogether, our findings corroborate the hypothesis that chronic exposure to anabolic-androgenic steroids induces dysfunction of the reward pathway in rats and might represent a potential risk factor for abuse of

  11. Alteration of time-resolved autofluorescence properties of rat aorta, induced by diabetes mellitus

    Science.gov (United States)

    Uherek, M.; Uličná, O.; Vančová, O.; Muchová, J.; Ďuračková, Z.; Šikurová, L.; Chorvát, D.

    2016-10-01

    Changes in autofluorescence properties of isolated rat aorta, induced by diabetes mellitus, were detected using time-resolved fluorescence spectroscopy with pulsed ultraviolet (UV) laser excitation. We demonstrated that time-resolved spectroscopy was able to detect changes in aorta tissues related to diabetes and unambiguously discriminate diabetic (τ 1 0.63  ±  0.05 ns, τ 2 3.66  ±  0.10 ns) samples from the control (τ 1 0.76  ±  0.03 ns, τ 2 4.48  ±  0.15 ns) group. We also report changes in the ratio of relative amplitudes of the two lifetime component in aorta tissue during diabetes, most likely related to the pseudohypoxic state with altered NADH homeostasis.

  12. Physical characterization of functionalized spider silk: electronic and sensing properties

    Science.gov (United States)

    Steven, Eden; Park, Jin Gyu; Paravastu, Anant; Branco Lopes, Elsa; Brooks, James S.; Englander, Ongi; Siegrist, Theo; Kaner, Papatya; Alamo, Rufina G.

    2011-10-01

    This work explores functional, fundamental and applied aspects of naturally harvested spider silk fibers. Natural silk is a protein polymer where different amino acids control the physical properties of fibroin bundles, producing, for example, combinations of β-sheet (crystalline) and amorphous (helical) structural regions. This complexity presents opportunities for functional modification to obtain new types of material properties. Electrical conductivity is the starting point of this investigation, where the insulating nature of neat silk under ambient conditions is described first. Modification of the conductivity by humidity, exposure to polar solvents, iodine doping, pyrolization and deposition of a thin metallic film are explored next. The conductivity increases exponentially with relative humidity and/or solvent, whereas only an incremental increase occurs after iodine doping. In contrast, iodine doping, optimal at 70 °C, has a strong effect on the morphology of silk bundles (increasing their size), on the process of pyrolization (suppressing mass loss rates) and on the resulting carbonized fiber structure (that becomes more robust against bending and strain). The effects of iodine doping and other functional parameters (vacuum and thin film coating) motivated an investigation with magic angle spinning nuclear magnetic resonance (MAS-NMR) to monitor doping-induced changes in the amino acid-protein backbone signature. MAS-NMR revealed a moderate effect of iodine on the helical and β-sheet structures, and a lesser effect of gold sputtering. The effects of iodine doping were further probed by Fourier transform infrared (FTIR) spectroscopy, revealing a partial transformation of β-sheet-to-amorphous constituency. A model is proposed, based on the findings from the MAS-NMR and FTIR, which involves iodine-induced changes in the silk fibroin bundle environment that can account for the altered physical properties. Finally, proof-of-concept applications of

  13. Physical characterization of functionalized spider silk: electronic and sensing properties

    Energy Technology Data Exchange (ETDEWEB)

    Steven, Eden; Brooks, James S [Department of Physics and National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac, Tallahassee, FL 32310 (United States); Park, Jin Gyu [FAMU-FSU Department of Industrial and Manufacturing Engineering, High-Performance Materials Institute, Florida State University, 2005 Levy Ave., Tallahassee, FL 32310 (United States); Paravastu, Anant; Siegrist, Theo; Kaner, Papatya; Alamo, Rufina G [FAMU-FSU Department of Chemical and Biomedical Engineering and National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac, Tallahassee, FL 32310 (United States); Branco Lopes, Elsa [Departamento de Quimica, Instituto Tecnologico e Nuclear/CFMC-UL, P-2686-953 Sacavem (Portugal); Englander, Ongi, E-mail: esteven@magnet.fsu.edu [FAMU-FSU Department of Mechanical Engineering and National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac, Tallahassee, Florida 32310 (United States)

    2011-10-15

    This work explores functional, fundamental and applied aspects of naturally harvested spider silk fibers. Natural silk is a protein polymer where different amino acids control the physical properties of fibroin bundles, producing, for example, combinations of {beta}-sheet (crystalline) and amorphous (helical) structural regions. This complexity presents opportunities for functional modification to obtain new types of material properties. Electrical conductivity is the starting point of this investigation, where the insulating nature of neat silk under ambient conditions is described first. Modification of the conductivity by humidity, exposure to polar solvents, iodine doping, pyrolization and deposition of a thin metallic film are explored next. The conductivity increases exponentially with relative humidity and/or solvent, whereas only an incremental increase occurs after iodine doping. In contrast, iodine doping, optimal at 70 deg. C, has a strong effect on the morphology of silk bundles (increasing their size), on the process of pyrolization (suppressing mass loss rates) and on the resulting carbonized fiber structure (that becomes more robust against bending and strain). The effects of iodine doping and other functional parameters (vacuum and thin film coating) motivated an investigation with magic angle spinning nuclear magnetic resonance (MAS-NMR) to monitor doping-induced changes in the amino acid-protein backbone signature. MAS-NMR revealed a moderate effect of iodine on the helical and {beta}-sheet structures, and a lesser effect of gold sputtering. The effects of iodine doping were further probed by Fourier transform infrared (FTIR) spectroscopy, revealing a partial transformation of {beta}-sheet-to-amorphous constituency. A model is proposed, based on the findings from the MAS-NMR and FTIR, which involves iodine-induced changes in the silk fibroin bundle environment that can account for the altered physical properties. Finally, proof

  14. Physical characterization of functionalized spider silk: electronic and sensing properties

    Directory of Open Access Journals (Sweden)

    Eden Steven, Jin Gyu Park, Anant Paravastu, Elsa Branco Lopes, James S Brooks, Ongi Englander, Theo Siegrist, Papatya Kaner and Rufina G Alamo

    2011-01-01

    Full Text Available This work explores functional, fundamental and applied aspects of naturally harvested spider silk fibers. Natural silk is a protein polymer where different amino acids control the physical properties of fibroin bundles, producing, for example, combinations of β-sheet (crystalline and amorphous (helical structural regions. This complexity presents opportunities for functional modification to obtain new types of material properties. Electrical conductivity is the starting point of this investigation, where the insulating nature of neat silk under ambient conditions is described first. Modification of the conductivity by humidity, exposure to polar solvents, iodine doping, pyrolization and deposition of a thin metallic film are explored next. The conductivity increases exponentially with relative humidity and/or solvent, whereas only an incremental increase occurs after iodine doping. In contrast, iodine doping, optimal at 70 °C, has a strong effect on the morphology of silk bundles (increasing their size, on the process of pyrolization (suppressing mass loss rates and on the resulting carbonized fiber structure (that becomes more robust against bending and strain. The effects of iodine doping and other functional parameters (vacuum and thin film coating motivated an investigation with magic angle spinning nuclear magnetic resonance (MAS-NMR to monitor doping-induced changes in the amino acid-protein backbone signature. MAS-NMR revealed a moderate effect of iodine on the helical and β-sheet structures, and a lesser effect of gold sputtering. The effects of iodine doping were further probed by Fourier transform infrared (FTIR spectroscopy, revealing a partial transformation of β-sheet-to-amorphous constituency. A model is proposed, based on the findings from the MAS-NMR and FTIR, which involves iodine-induced changes in the silk fibroin bundle environment that can account for the altered physical properties. Finally, proof

  15. Altered proliferation and differentiation properties of primary mammary epithelial cells from BRCA1 mutation carriers.

    Science.gov (United States)

    Burga, Laura N; Tung, Nadine M; Troyan, Susan L; Bostina, Mihnea; Konstantinopoulos, Panagiotis A; Fountzilas, Helena; Spentzos, Dimitrios; Miron, Alexander; Yassin, Yosuf A; Lee, Bernard T; Wulf, Gerburg M

    2009-02-15

    Female BRCA1 mutation carriers have a nearly 80% probability of developing breast cancer during their life-time. We hypothesized that the breast epithelium at risk in BRCA1 mutation carriers harbors mammary epithelial cells (MEC) with altered proliferation and differentiation properties. Using a three-dimensional culture technique to grow MECs ex vivo, we found that the ability to form colonies, an indication of clonality, was restricted to the aldehyde dehydrogenase 1-positive fraction in MECs but not in HCC1937 BRCA1-mutant cancer cells. Primary MECs from BRCA1 mutation carriers (n = 9) had a 28% greater ability for clonal growth compared with normal controls (n = 6; P = 0.006), and their colonies were significantly larger. Colonies in controls and BRCA1 mutation carriers stained positive for BRCA1 by immunohistochemistry, and 79% of the examined single colonies from BRCA1 carriers retained heterozygosity for BRCA1 (ROH). Colonies from BRCA1 mutation carriers frequently showed high epidermal growth factor receptor (EGFR) expression (71% EGFR positive versus 44% in controls) and were negative for estrogen receptor (ERalpha; 32% ER negative, 44% mixed, 24% ER positive versus 90% ER positive in controls). Expression of CK14 and p63 were not significantly different. Microarray studies revealed that colonies from BRCA1-mutant PMECs anticipate expression profiles found in BRCA1-related tumors, and that the EGFR pathway is up-regulated. We conclude that BRCA1 haploinsufficiency leads to an increased ability for clonal growth and proliferation in the PMECs of BRCA1 mutation carriers, possibly as a result of EGFR pathway activation. These altered growth and differentiation properties may render BRCA1-mutant PMECs vulnerable to transformation and predispose to the development of ER-negative, EGFR-positive breast cancers.

  16. Hierarchical alteration of brain structural and functional networks in female migraine sufferers.

    Directory of Open Access Journals (Sweden)

    Jixin Liu

    Full Text Available BACKGROUND: Little is known about the changes of brain structural and functional connectivity networks underlying the pathophysiology in migraine. We aimed to investigate how the cortical network reorganization is altered by frequent cortical overstimulation associated with migraine. METHODOLOGY/PRINCIPAL FINDINGS: Gray matter volumes and resting-state functional magnetic resonance imaging signal correlations were employed to construct structural and functional networks between brain regions in 43 female patients with migraine (PM and 43 gender-matched healthy controls (HC by using graph theory-based approaches. Compared with the HC group, the patients showed abnormal global topology in both structural and functional networks, characterized by higher mean clustering coefficients without significant change in the shortest absolute path length, which indicated that the PM lost optimal topological organization in their cortical networks. Brain hubs related to pain-processing revealed abnormal nodal centrality in both structural and functional networks, including the precentral gyrus, orbital part of the inferior frontal gyrus, parahippocampal gyrus, anterior cingulate gyrus, thalamus, temporal pole of the middle temporal gyrus and the inferior parietal gyrus. Negative correlations were found between migraine duration and regions with abnormal centrality. Furthermore, the dysfunctional connections in patients' cortical networks formed into a connected component and three dysregulated modules were identified involving pain-related information processing and motion-processing visual networks. CONCLUSIONS: Our results may reflect brain alteration dynamics resulting from migraine and suggest that long-term and high-frequency headache attacks may cause both structural and functional connectivity network reorganization. The disrupted information exchange between brain areas in migraine may be reshaped into a hierarchical modular structure progressively.

  17. Tissue-specific alterations in expression and function of P-glycoprotein in streptozotocininduced diabetic rats

    Institute of Scientific and Technical Information of China (English)

    Lu-lu ZHANG; Guang-ji WANG; Lin XIE; Liang LU; Shi JIN; Xin-yue JING; Dan YAO; Nan HU; Li LIU; Ru DUAN; Xiao-dong LIU

    2011-01-01

    Aim: To investigate the changes of expression and function of P-glycoprotein (P-GP) in cerebral cortex, hippocampus, liver, intestinal mucosa and kidney of streptozocin-induced diabetic rats.Methods: Diabetic rats were prepared via a single dose of streptozocin (65 mg/kg, ip). Abcb1/P-GP mRNA and protein expression levels in tissues were evaluated using quantitative real time polymerase chain reaction (QRT-PCR) analysis and Western blot, respectively.P-GP function was investigated via measuring tissue-to-plasma concentration ratios and body fluid excretion percentages of rhodamine 123.Results: In 5- and 8-week diabetic rats, Abcb1a mRNA levels were significantly decreased in cerebral cortices and intestinal mucosa,but dramatically increased in hippocampus and kidney. In liver, the level was increased in 5-week diabetic rats, and decreased in 8-week diabetic rats. Abcb1b mRNA levels were increased in cerebral cortex, hippocampus and kidney, but reduced in liver and intestinal mucosa in the diabetic rats. Western blot results were in accordance with the alterations of Abcb1a mRNA levels in most tissues examined. P-GP activity was markedly decreased in most tissues of diabetic rats, except kidney tissues.Conclusion: Alterations in the expression and function of Abcb1/P-GP under diabetic conditions are tissue specific, Abcb1 specific and diabetic duration-dependent.

  18. From gut dysbiosis to altered brain function and mental illness: mechanisms and pathways

    Science.gov (United States)

    Rogers, G B; Keating, D J; Young, R L; Wong, M-L; Licinio, J; Wesselingh, S

    2016-01-01

    The human body hosts an enormous abundance and diversity of microbes, which perform a range of essential and beneficial functions. Our appreciation of the importance of these microbial communities to many aspects of human physiology has grown dramatically in recent years. We know, for example, that animals raised in a germ-free environment exhibit substantially altered immune and metabolic function, while the disruption of commensal microbiota in humans is associated with the development of a growing number of diseases. Evidence is now emerging that, through interactions with the gut–brain axis, the bidirectional communication system between the central nervous system and the gastrointestinal tract, the gut microbiome can also influence neural development, cognition and behaviour, with recent evidence that changes in behaviour alter gut microbiota composition, while modifications of the microbiome can induce depressive-like behaviours. Although an association between enteropathy and certain psychiatric conditions has long been recognized, it now appears that gut microbes represent direct mediators of psychopathology. Here, we examine roles of gut microbiome in shaping brain development and neurological function, and the mechanisms by which it can contribute to mental illness. Further, we discuss how the insight provided by this new and exciting field of research can inform care and provide a basis for the design of novel, microbiota-targeted, therapies. PMID:27090305

  19. Maternal Hyperleptinemia Is Associated with Male Offspring's Altered Vascular Function and Structure in Mice.

    Directory of Open Access Journals (Sweden)

    Kathleen A Pennington

    Full Text Available Children of mothers with gestational diabetes have greater risk of developing hypertension but little is known about the mechanisms by which this occurs. The objective of this study was to test the hypothesis that high maternal concentrations of leptin during pregnancy, which are present in mothers with gestational diabetes and/or obesity, alter blood pressure, vascular structure and vascular function in offspring. Wildtype (WT offspring of hyperleptinemic, normoglycemic, Leprdb/+ dams were compared to genotype matched offspring of WT-control dams. Vascular function was assessed in male offspring at 6, and at 31 weeks of age after half the offspring had been fed a high fat, high sucrose diet (HFD for 6 weeks. Blood pressure was increased by HFD but not affected by maternal hyperleptinemia. On a standard diet, offspring of hyperleptinemic dams had outwardly remodeled mesenteric arteries and an enhanced vasodilatory response to insulin. In offspring of WT but not Leprdb/+ dams, HFD induced vessel hypertrophy and enhanced vasodilatory responses to acetylcholine, while HFD reduced insulin responsiveness in offspring of hyperleptinemic dams. Offspring of hyperleptinemic dams had stiffer arteries regardless of diet. Therefore, while maternal hyperleptinemia was largely beneficial to offspring vascular health under a standard diet, it had detrimental effects in offspring fed HFD. These results suggest that circulating maternal leptin concentrations may interact with other factors in the pre- and post -natal environments to contribute to altered vascular function in offspring of diabetic pregnancies.

  20. Understanding heavy-oil molecular functionality and relations to fluid properties

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, S.I. [Schlumberger, DBR Technology Center, Edmonton AB (Canada)

    2011-07-01

    In the heavy oil industry, knowing oil properties is important to optimizing recovery, transport and refinery. Nitrogen, sulfur and oxygen compounds (NSOs) have an important impact on these properties but this is often overlooked. The purpose of this paper is to analyze the impact of functional groups in connection with heavy oil and asphaltenes. Experiments were carried out with asphaltenes altered by chemical surgery that removed specific functional interactions. Titration calorimetry and fluorescence spectroscopy were then done. Results highlighted the fact that functional groups are of key importance in the determination of heavy oil properties and that acidity can be considered the most important interaction. This paper demonstrated that the determination of specific interactions could be more important in assessing heavy oil properties than understanding their hydrocarbon structure; further work is needed to fully understand the role of sulfur and nitrogen species.

  1. CO2-induced ocean acidification increases anxiety in rockfish via alteration of GABAA receptor functioning.

    Science.gov (United States)

    Hamilton, Trevor James; Holcombe, Adam; Tresguerres, Martin

    2014-01-22

    The average surface pH of the ocean is dropping at a rapid rate due to the dissolution of anthropogenic CO2, raising concerns for marine life. Additionally, some coastal areas periodically experience upwelling of CO2-enriched water with reduced pH. Previous research has demonstrated ocean acidification (OA)-induced changes in behavioural and sensory systems including olfaction, which is due to altered function of neural gamma-aminobutyric acid type A (GABAA) receptors. Here, we used a camera-based tracking software system to examine whether OA-dependent changes in GABAA receptors affect anxiety in juvenile Californian rockfish (Sebastes diploproa). Anxiety was estimated using behavioural tests that measure light/dark preference (scototaxis) and proximity to an object. After one week in OA conditions projected for the next century in the California shore (1125 ± 100 µatm, pH 7.75), anxiety was significantly increased relative to controls (483 ± 40 µatm CO2, pH 8.1). The GABAA-receptor agonist muscimol, but not the antagonist gabazine, caused a significant increase in anxiety consistent with altered Cl(-) flux in OA-exposed fish. OA-exposed fish remained more anxious even after 7 days back in control seawater; however, they resumed their normal behaviour by day 12. These results show that OA could severely alter rockfish behaviour; however, this effect is reversible.

  2. Renal Oxidative Stress Induced by Long-Term Hyperuricemia Alters Mitochondrial Function and Maintains Systemic Hypertension

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    Magdalena Cristóbal-García

    2015-01-01

    Full Text Available We addressed if oxidative stress in the renal cortex plays a role in the induction of hypertension and mitochondrial alterations in hyperuricemia. A second objective was to evaluate whether the long-term treatment with the antioxidant Tempol prevents renal oxidative stress, mitochondrial alterations, and systemic hypertension in this model. Long-term (11-12 weeks and short-term (3 weeks effects of oxonic acid induced hyperuricemia were studied in rats (OA, 750 mg/kg BW, OA+Allopurinol (AP, 150 mg/L drinking water, OA+Tempol (T, 15 mg/kg BW, or vehicle. Systolic blood pressure, renal blood flow, and vascular resistance were measured. Tubular damage (urine N-acetyl-β-D-glucosaminidase and oxidative stress markers (lipid and protein oxidation along with ATP levels were determined in kidney tissue. Oxygen consumption, aconitase activity, and uric acid were evaluated in isolated mitochondria from renal cortex. Short-term hyperuricemia resulted in hypertension without demonstrable renal oxidative stress or mitochondrial dysfunction. Long-term hyperuricemia induced hypertension, renal vasoconstriction, tubular damage, renal cortex oxidative stress, and mitochondrial dysfunction and decreased ATP levels. Treatments with Tempol and allopurinol prevented these alterations. Renal oxidative stress induced by hyperuricemia promoted mitochondrial functional disturbances and decreased ATP content, which represent an additional pathogenic mechanism induced by chronic hyperuricemia. Hyperuricemia-related hypertension occurs before these changes are evident.

  3. Endomorphins delay constitutive apoptosis and alter the innate host defense functions of neutrophils.

    Science.gov (United States)

    Azuma, Yasutaka; Ohura, Kiyoshi; Wang, Pao-Li; Shinohara, Mitsuko

    2002-04-01

    Recent studies have shown that opioid peptides are released from cells of the immune system during inflammation and stress, and are associated with altered immune responses. Moreover, concentrations of opioid peptides are increased in peripheral blood and at the sites of inflammatory reactions. The aim of this study was to evaluate immunological effects of opioid peptides endomorphins 1 and 2 on constitutive apoptosis, superoxide anion production, hydrogen peroxide production, adhesion, phagocytosis, and chemotaxis of neutrophils. Neutrophils were isolated by peritoneal lavage from rats. Endomorphins 1 and 2 significantly delayed constitutive neutrophil apoptosis. The delay of neutrophil apoptosis was markedly attenuated by LY294002, a phosphoinositide 3-kinase inhibitor. Moreover, endomorphins 1 and 2 activated the phosphoinositide 3-kinase pathway as determined by phosphorylation of BAD. In contrast, endomorphins 1 and 2 blocked the production of superoxide anion and hydrogen peroxide by PMA-stimulated neutrophils. In addition, endomorphins 1 and 2 inhibited neutrophil adhesion to fibronectin. Moreover, endomorphins 1 and 2 potentiated neutrophil chemotaxis toward zymosan-activated serum and IL-8, respectively. However, endomorphins 1 and 2 did not alter phagocytosis of Escherichia coli by neutrophils. These results suggest that endomorphins 1 and 2 may act to delay neutrophil apoptosis and alter the natural immune functions of neutrophils.

  4. Corticotropin-releasing factor receptors and stress-related alterations of gut motor function.

    Science.gov (United States)

    Taché, Yvette; Bonaz, Bruno

    2007-01-01

    Over the past few decades, corticotropin-releasing factor (CRF) signaling pathways have been shown to be the main coordinators of the endocrine, behavioral, and immune responses to stress. Emerging evidence also links the activation of CRF receptors type 1 and type 2 with stress-related alterations of gut motor function. Here, we review the role of CRF receptors in both the brain and the gut as part of key mechanisms through which various stressors impact propulsive activity of the gastrointestinal system. We also examine how these mechanisms translate into the development of new approaches for irritable bowel syndrome, a multifactorial disorder for which stress has been implicated in the pathophysiology.

  5. Certain Properties of q-Hypergeometric Functions

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    Uzoamaka A. Ezeafulukwe

    2015-01-01

    Full Text Available The quotients of certain q-hypergeometric functions are presented as g-fractions which converge uniformly in the unit disc. These results lead to the existence of certain q-hypergeometric functions in the class of either q-convex functions, PCq, or q-starlike functions PSq*.

  6. Influenza matrix protein 2 alters CFTR expression and function through its ion channel activity.

    Science.gov (United States)

    Londino, James D; Lazrak, Ahmed; Jurkuvenaite, Asta; Collawn, James F; Noah, James W; Matalon, Sadis

    2013-05-01

    The human cystic fibrosis transmembrane conductance regulator (CFTR) is a cyclic AMP-activated chloride (Cl(-)) channel in the lung epithelium that helps regulate the thickness and composition of the lung epithelial lining fluid. We investigated whether influenza M2 protein, a pH-activated proton (H(+)) channel that traffics to the plasma membrane of infected cells, altered CFTR expression and function. M2 decreased CFTR activity in 1) Xenopus oocytes injected with human CFTR, 2) epithelial cells (HEK-293) stably transfected with CFTR, and 3) human bronchial epithelial cells (16HBE14o-) expressing native CFTR. This inhibition was partially reversed by an inhibitor of the ubiquitin-activating enzyme E1. Next we investigated whether the M2 inhibition of CFTR activity was due to an increase of secretory organelle pH by M2. Incubation of Xenopus oocytes expressing CFTR with ammonium chloride or concanamycin A, two agents that alkalinize the secretory pathway, inhibited CFTR activity in a dose-dependent manner. Treatment of M2- and CFTR-expressing oocytes with the M2 ion channel inhibitor amantadine prevented the loss in CFTR expression and activity; in addition, M2 mutants, lacking the ability to transport H(+), did not alter CFTR activity in Xenopus oocytes and HEK cells. Expression of an M2 mutant retained in the endoplasmic reticulum also failed to alter CFTR activity. In summary, our data show that M2 decreases CFTR activity by increasing secretory organelle pH, which targets CFTR for destruction by the ubiquitin system. Alteration of CFTR activity has important consequences for fluid regulation and may potentially modify the immune response to viral infection.

  7. Scintigraphic Methods to Evaluate Alterations of Gastric and Esophageal Functions in Female Obesity

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    Özgür Ömür

    2014-02-01

    Full Text Available Objective: Altered gastrointestinal function has frequently been observed in obese patients. The aim of this study was to investigate the frequency of gastro-esophageal reflux (GER and to determine the alterations of gastric emptying and esophageal transit by scintigraphic methods in obese patients. Methods: Scintigraphic studies of 50 obese female non-diabetic patients who had not received any treatment for weight control were retrospectively reviewed. Mean Body Mass Index (BMI was 34.96±3.04 kg/m² (range:32-39 kg/m². All subjects were submitted to scintigraphic evaluation of esophageal transit, gastro-esophageal reflux, gastric emptying and presence of Helicobacter pylori infection. The data of obese patients were compared with those of sex-age matched 30 non-obese cases who were selected from our clinical archive. Results: In obese group, seventeen (34% patients were found to be GER positive scintigraphically; mean gastric emptying time (t½ was 59.18±30.8 min and the mean esophageal transit time was 8.9±7.2 s. Frequency of positive GER scintigraphy and the mean value of esophageal transit time were significantly higher in obese patients than non-obese control subjects. Gastric emptying time and esophageal transit time values were significantly longer in GER positive obese patients than GER negative ones. There was no statistically significant difference in the frequency of positive C14 urea breath test between obese and non-obese subjects and there were also no statistically significant correlations between BMI, GER, esophageal transit time and gastric emptying time. Conclusion: In our study, 42 of the 50 obese patients had esophago-gastric motility alterations. The significance of these alterations in obesity is not fully understood, but it is believed that these changes could be because of potential contributing factors in the development or maintenance of obesity or changes in eating habits

  8. Effect of land use change on soil properties and functions

    Science.gov (United States)

    Tonutare, Tonu; Kõlli, Raimo; Köster, Tiina; Rannik, Kaire; Szajdak, Lech; Shanskiy, Merrit

    2014-05-01

    , and pedo-ecological conditions. LUC from natural to arable is accompanied by different regulations: (1) regular restoration of plant available nutrition elements' stocks in soil, (2) regulation (if needed) of water regime of gleyed and gley soils, (3) optimizing of soil actual acidity by liming, and (4) forming a suitable for crops seed bed instead of natural epipedon. Principal changes are occurred in fabric and agrochemical properties of topsoil and in soil functioning. The connected with LUC changes in soil functioning are: (1) increase of openness level of chemical elements cycling and nutrition elements concentration in phytomass, and (2) decrease of total phytomass, species diversity, amount of annual falling litter and content of mortmass in soil cover. These changes lead to decreasing of biological control on soil resources, flux of energy and substances to soil processes, and volume of cycling. At the same time the intensity of organic matter decomposition and outflow of nutrition elements are increased. All these changes are resulted by alteration of food chains and exhausting of nutrition elements' stocks. The changes in soil functioning (decrease or increase of productivity) depend much on soil type. The aspects of functioning, which do not changed with LUC are chemical-textural potential of soil cover and functioning character of subsoil. The sound matching of soil and plant cover is of decisive importance for sustainable functioning of ecosystem and in attaining a good environmental status of the area.

  9. Malaria Parasite Proteins and Their Role in Alteration of the Structure and Function of Red Blood Cells.

    Science.gov (United States)

    Proellocks, Nicholas I; Coppel, Ross L; Mohandas, Narla; Cooke, Brian M

    2016-01-01

    Malaria, caused by Plasmodium spp., continues to be a major threat to human health and a significant cause of socioeconomic hardship in many countries. Almost half of the world's population live in malaria-endemic regions and many of them suffer one or more, often life-threatening episodes of malaria every year, the symptoms of which are attributable to replication of the parasite within red blood cells (RBCs). In the case of Plasmodium falciparum, the species responsible for most malaria-related deaths, parasite replication within RBCs is accompanied by striking alterations to the morphological, biochemical and biophysical properties of the host cell that are essential for the parasites' survival. To achieve this, the parasite establishes a unique and extensive protein export network in the infected RBC, dedicating at least 6% of its genome to the process. Understanding the full gamut of proteins involved in this process and the mechanisms by which P. falciparum alters the structure and function of RBCs is important both for a more complete understanding of the pathogenesis of malaria and for development of new therapeutic strategies to prevent or treat this devastating disease. This review focuses on what is currently known about exported parasite proteins, their interactions with the RBC and their likely pathophysiological consequences.

  10. Maternal mobile phone exposure alters intrinsic electrophysiological properties of CA1 pyramidal neurons in rat offspring.

    Science.gov (United States)

    Razavinasab, Moazamehosadat; Moazzami, Kasra; Shabani, Mohammad

    2016-06-01

    Some studies have shown that exposure to electromagnetic field (EMF) may result in structural damage to neurons. In this study, we have elucidated the alteration in the hippocampal function of offspring Wistar rats (n = 8 rats in each group) that were chronically exposed to mobile phones during their gestational period by applying behavioral, histological, and electrophysiological tests. Rats in the EMF group were exposed to 900 MHz pulsed-EMF irradiation for 6 h/day. Whole cell recordings in hippocampal pyramidal cells in the mobile phone groups did show a decrease in neuronal excitability. Mobile phone exposure was mostly associated with a decrease in the number of action potentials fired in spontaneous activity and in response to current injection in both male and female groups. There was an increase in the amplitude of the afterhyperpolarization (AHP) in mobile phone rats compared with the control. The results of the passive avoidance and Morris water maze assessment of learning and memory performance showed that phone exposure significantly altered learning acquisition and memory retention in male and female rats compared with the control rats. Light microscopy study of brain sections of the control and mobile phone-exposed rats showed normal morphology.Our results suggest that exposure to mobile phones adversely affects the cognitive performance of both female and male offspring rats using behavioral and electrophysiological techniques.

  11. Altered amygdala and hippocampus function in adolescents with hypercortisolemia: a functional magnetic resonance imaging study of Cushing syndrome.

    Science.gov (United States)

    Maheu, Françoise S; Mazzone, Luigi; Merke, Deborah P; Keil, Margaret F; Stratakis, Constantine A; Pine, Daniel S; Ernst, Monique

    2008-01-01

    Chronic elevations of endogenous cortisol levels have been shown to alter medial temporal cortical structures and to be accompanied by declarative memory impairments and depressive symptoms in human adults. These effects of elevated endogenous levels of cortisol have not been directly studied in adolescents. Because adolescents with Cushing syndrome show endogenous elevations in cortisol, they represent a unique natural model to study the effects of prolonged hypercortisolemia on brain function, and memory and affective processes during this developmental stage. Using functional magnetic resonance imaging (fMRI), we compared 12 adolescents with Cushing syndrome with 22 healthy control adolescents on amygdala and anterior hippocampus activation during an emotional faces encoding task. None of these adolescents manifested depressive symptoms. Encoding success was assessed using a memory recognition test performed after the scan. The fMRI analyses followed an event-related design and were conducted using the SPM99 platform. Compared to healthy adolescents, patients with Cushing syndrome showed greater left amygdala and right anterior hippocampus activation during successful face encoding. Memory performance for faces recognition did not differ between groups. This first study of cerebral function in adolescents with chronic endogenous hypercortisolemia due to Cushing syndrome demonstrates the presence of functional alterations in amygdala and hippocampus, which are not associated with affective or memory impairments. Such findings need to be followed by work examining the role of age and related brain maturational stage on these effects, as well as the identification of possible protective factors conferring resilience to affective and cognitive consequences in this disease and/or during this stage of cerebral development.

  12. Hydrothermal alteration of surficial rocks at Solfatara (Campi Flegrei): Petrophysical properties and implications for phreatic eruption processes

    Science.gov (United States)

    Mayer, Klaus; Scheu, Bettina; Montanaro, Cristian; Yilmaz, Tim I.; Isaia, Roberto; Aßbichler, Donjá; Dingwell, Donald B.

    2016-06-01

    Solfatara crater is located within the Campi Flegrei caldera to the west of Naples (Italy). It is one of the largest fumarolic manifestations known, and the rocks hosting the hydrothermal system are affected by intense hydrothermal alteration. Alteration can result in changes of degassing behavior, and in the formation of a cap rock thereby increasing the probability of phreatic eruptions. Here, we investigate the effects of alunitic (solfataric) alteration on the mineralogy, the physical properties (porosity, density, permeability) and the mechanical properties (strength) of the rocks involved, as well as its influence on fragmentation and ejection behavior. Our results show that the pristine mineralogy of deposits from the vicinity of the Solfatara cryptodome and from Pisciarelli is almost completely replaced by amorphous silica and alunite. The differences in the degree of alteration among the samples series are reflected in the investigated properties and behavior as well as in the analysis of the experimentally generated particles. Alunitic alteration increases porosity and permeability, whereas it reduces density, elastic wave velocity and strength leading to higher fragmentation and ejection speeds for the sample series examined in this study. Our results also show that alteration results in the generation of a high fraction of fines (particle sizes < 10 μm) during fragmentation, mainly composed of alunite crystals. Due to their potential for inducing chronic disease, dispersion of such material should represent a serious health hazard on a local scale and the evaluation of precautions should be considered.

  13. Hyperlipidemia Alters Regulatory T Cell Function and Promotes Resistance to Tolerance Induction Through Costimulatory Molecule Blockade.

    Science.gov (United States)

    Bagley, J; Yuan, J; Chandrakar, A; Iacomini, J

    2015-09-01

    Recent work from our laboratory has shown that hyperlipidemia promotes accelerated rejection of vascularized cardiac allografts in mice by inducing anti-donor Th17 reactivity and production of IL-17. Here, we show that hyperlipidemia also affects FoxP3(+) regulatory T cells (Tregs). Hyperlipidemia promotes the development of Tregs that express low levels of CD25. Hyperlipidemia also promotes a decrease in central Tregs and an increase in effector Tregs that appears to account for the increase in the frequency of CD25(low) Tregs. Alterations in Treg subsets also appear to lead to alterations in Treg function. The ability of FoxP3(+) , CD25(high) , CD4(+) Tregs from hyperlipidemic mice to inhibit proliferation of effector T cells stimulated with anti-CD3 and CD28 was reduced when compared with Tregs from control mice. Regulatory T cells isolated from hyperlipidemic recipients exhibit increased activation of Akt, and a reduction in Bim levels that permits the expansion of FoxP3(+) CD25(low) CD4(+) T cells. Hyperlipidemic mice were also resistant to tolerance induction using costimulatory molecule blockade consisting of anti-CD154 and CTLA4Ig, a strategy that requires Tregs. Together, our data suggest that hyperlipidemia profoundly affects Treg subsets and function as well as the ability to induce tolerance.

  14. Alteration of split renal function during Captopril treatment. Diagnostic significance in renovascular hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Aburano, Tamio; Takayama, Teruhiko; Nakajima, Kenichi; Tonami, Norihisa; Hisada, Kinichi; Yasuhara, Shuichirou; Miyamori, Isamu; Takeda, Ryoyu

    1987-07-01

    Two different methods to evaluate the alteration of split renal function following continued Captopril treatment were studied in a total of 21 patients with hypertension. Eight patients with renovascular hypertension (five with unilateral renal artery stenosis and three with bilateral renal artery stenoses), three patients with diabetic nephropathy, one patient with primary aldosteronism, and nine patients with essential hypertension were included. The studies were performed the day prior to receiving Captopril (baseline), and 6th or 7th day following continued Captopril treatment (37.5 mg or 75 mg/day). Split effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) after injections of I-131 hippuran and Tc-99m DTPA were measured using kidney counting corrected for depth and dose, described by Schlegel and Gates. In the patients with renovascular hypertension, split GFR in the stenotic kidney was significantly decreased 6th or 7th day following continued Captopril treatment compared to a baseline value. And split ERPF in the stenotic kidney was slightly increased although significant increase of split ERPF was not shown. In the patients with diabetic nephropathy, primary aldosteronism or essential hypertension, on the other hand, split GFR was not changed and split ERPF was slightly increased. These findings suggest that the Captopril induced alterations of split renal function may be of importance for the diagnosis of renovascular hypertension. For this purpose, split GFR determination is more useful than split ERPF determination.

  15. Physiologic and pathophysiologic consequences of altered sialylation and glycosylation on ion channel function.

    Science.gov (United States)

    Baycin-Hizal, Deniz; Gottschalk, Allan; Jacobson, Elena; Mai, Sunny; Wolozny, Daniel; Zhang, Hui; Krag, Sharon S; Betenbaugh, Michael J

    2014-10-17

    Voltage-gated ion channels are transmembrane proteins that regulate electrical excitability in cells and are essential components of the electrically active tissues of nerves, muscle and the heart. Potassium channels are one of the largest subfamilies of voltage sensitive channels and are among the most-studied of the voltage-gated ion channels. Voltage-gated channels can be glycosylated and changes in the glycosylation pattern can affect ion channel function, leading to neurological and neuromuscular disorders and congenital disorders of glycosylation (CDG). Alterations in glycosylation can also be acquired and appear to play a role in development and aging. Recent studies have focused on the impact of glycosylation and sialylation on ion channels, particularly for voltage-gated potassium and sodium channels. The terminal step of sialylation often affects channel activation and inactivation kinetics. The presence of sialic acids on O or N-glycans can alter the gating mechanism and cause conformational changes in the voltage-sensing domains due to sialic acid's negative charges. This manuscript will provide an overview of sialic acids, potassium and sodium channel function, and the impact of sialylation on channel activation and deactivation.

  16. Dendritic surface functionalization of nanomaterials: controlling properties and functions for biomedical applications

    Directory of Open Access Journals (Sweden)

    Ali Nazemi

    2013-01-01

    Full Text Available A wide variety of nanomaterials have demonstrated promise in medical applications such as drug delivery and imaging. In these applications, the surface chemistry of the materials is critical as it plays an important role in determining the toxicity and biodistribution behavior of the material. We review here the functionalization of nanomaterials with dendrons as an efficient method to alter the surface chemistry of the materials, introducing new properties and functions. Described here is the functionalization of superparamagnetic iron oxide nanoparticles (SPIO with dendritic guanidines to enhance their transport into cells for magnetic resonance imaging applications. The introduction of dendrons bearing peripheral hydroxyls, amines, guanidines, carbohydrates and Gd(III chelates to polymer vesicles (polymersomes is also described. These dendritic moieties allow for modulation of toxicity, cell uptake, protein binding, and contrast agent efficiency, while at the same time allowing the stabilities of the polymersomes to be maintained. Thus, this approach holds promise for the development of a wide range of multifunctional materials for pharmaceutical applications.

  17. Association between functional alterations of senescence and senility and disorders of gait and balance

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    Homero Teixeira-Leite

    2012-07-01

    Full Text Available OBJECTIVES: Declines in cognition and mobility are frequently observed in the elderly, and it has been suggested that the appearance of gait disorders in older individuals may constitute a marker of cognitive decline that precedes significant findings in functional performance screening tests. This study sought to evaluate the relationship between functional capacities and gait and balance in an elderly community monitored by the Preventive and Integrated Care Unit of the Hospital Adventista Silvestre in Rio de Janeiro, RJ, Brazil. METHODS: Elderly individuals (193 females and 90 males were submitted to a broad geriatric evaluation, which included the following tests: 1 a performance-oriented mobility assessment (POMA to evaluate gait; 2 a mini-mental state examination (MMSE; 3 the use of Katz and Lawton scales to assess functional capacity; 4 the application of the geriatric depression scale (GDS; and 5 a mini-nutritional assessment (MNA scale. RESULTS: Reductions in MMSE, Katz and Lawton scores were associated with reductions in POMA scores, and we also observed that significant reductions in POMA scores were present in persons for whom the MMSE and Katz scores did not clearly indicate cognitive dysfunction. We also demonstrated that a decline in the scores obtained with the GDS and MNA scales was associated with a decline in the POMA scores. CONCLUSIONS: Considering that significant alterations in the POMA scores were observed prior to the identification of significant alterations in cognitive capacity using either the MMSE or the Katz systems, a prospective study seems warranted to assess the predictive capacity of POMA scores regarding the associated decline in functional capacity.

  18. Ethanol exposure alters early cardiac function in the looping heart: a mechanism for congenital heart defects?

    Science.gov (United States)

    Karunamuni, Ganga; Gu, Shi; Doughman, Yong Qiu; Peterson, Lindsy M; Mai, Katherine; McHale, Quinn; Jenkins, Michael W; Linask, Kersti K; Rollins, Andrew M; Watanabe, Michiko

    2014-02-01

    Alcohol-induced congenital heart defects are frequently among the most life threatening and require surgical correction in newborns. The etiology of these defects, collectively known as fetal alcohol syndrome, has been the focus of much study, particularly involving cellular and molecular mechanisms. Few studies have addressed the influential role of altered cardiac function in early embryogenesis because of a lack of tools with the capability to assay tiny beating hearts. To overcome this gap in our understanding, we used optical coherence tomography (OCT), a nondestructive imaging modality capable of micrometer-scale resolution imaging, to rapidly and accurately map cardiovascular structure and hemodynamics in real time under physiological conditions. In this study, we exposed avian embryos to a single dose of alcohol/ethanol at gastrulation when the embryo is sensitive to the induction of birth defects. Late-stage hearts were analyzed using standard histological analysis with a focus on the atrio-ventricular valves. Early cardiac function was assayed using Doppler OCT, and structural analysis of the cardiac cushions was performed using OCT imaging. Our results indicated that ethanol-exposed embryos developed late-stage valvuloseptal defects. At early stages, they exhibited increased regurgitant flow and developed smaller atrio-ventricular cardiac cushions, compared with controls (uninjected and saline-injected embryos). The embryos also exhibited abnormal flexion/torsion of the body. Our evidence suggests that ethanol-induced alterations in early cardiac function have the potential to contribute to late-stage valve and septal defects, thus demonstrating that functional parameters may serve as early and sensitive gauges of cardiac normalcy and abnormalities.

  19. Functional and morphological alterations associated with working memory dysfunction in patients with generalized anxiety disorder.

    Science.gov (United States)

    Moon, Chung-Man; Jeong, Gwang-Woo

    2017-03-01

    Background Generalized anxiety disorder (GAD) has been related to functional brain activities and structural brain abnormalities. Purpose To investigate the neural mechanism on working memory dysfunction in patients with GAD in terms of the combined functional and morphological brain abnormalities. Material and Methods Patients with GAD and healthy controls matched for age, sex, and education level underwent high-resolution T1-weighted (T1W) magnetic resonance imaging (MRI) and functional MRI (fMRI). In this study, fMRI and voxel-based morphometry (VBM) were used for assessing the differential brain activation patterns, as well as for comparing the morphological alterations between the two groups. Results In response to the neutral distractors, the patients showed significantly lower activities in the regions of the fusiform gyrus (FuG), superior parietal gyrus (SPG), precuneus (PCu), superior occipital gyrus (SOG), lingual gyrus (LiG), cuneus (Cun), calcarine cortex (CaC), parahippocampal gyrus (PHG) and cerebellar cortex (Cb) compared to the controls. In response to the anxiety-inducing distractors, the patients showed significantly higher activity in the hippocampus and lower activities in the regions of the dorsolateral prefrontal cortex (DLPFC), FuG, SPG, PCu, SOG, and Cb. Also, the patients showed a significant reduction of the white matter volumes in the DLPFC, anterior limb of the internal capsule (ALIC) and midbrain. Conclusion This study provides the first evidence for the association between the morphometric alterations and functional deficit in the working memory processing with the neutral and anxiety-inducing distractors in GAD patients. These findings would be helpful to understand the neural mechanisms on working memory impairment in connection with GAD symptoms.

  20. Proteomic analysis and functional characterization of mouse brain mitochondria during aging reveal alterations in energy metabolism.

    Science.gov (United States)

    Stauch, Kelly L; Purnell, Phillip R; Villeneuve, Lance M; Fox, Howard S

    2015-05-01

    Mitochondria are the main cellular source of reactive oxygen species and are recognized as key players in several age-associated disorders and neurodegeneration. Their dysfunction has also been linked to cellular aging. Additionally, mechanisms leading to the preservation of mitochondrial function promote longevity. In this study we investigated the proteomic and functional alterations in brain mitochondria isolated from mature (5 months old), old (12 months old), and aged (24 months old) mice as determinants of normal "healthy" aging. Here the global changes concomitant with aging in the mitochondrial proteome of mouse brain analyzed by quantitative mass-spectrometry based super-SILAC identified differentially expressed proteins involved in several metabolic pathways including glycolysis, the tricarboxylic acid cycle, and oxidative phosphorylation. Despite these changes, the bioenergetic function of these mitochondria was preserved. Overall, this data indicates that proteomic changes during aging may compensate for functional defects aiding in preservation of mitochondrial function. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium with the data set identifier PXD001370 (http://proteomecentral.proteomexchange.org/dataset/PXD001370).

  1. Mutations in the catalytic loop HRD motif alter the activity and function of Drosophila Src64.

    Directory of Open Access Journals (Sweden)

    Taylor C Strong

    Full Text Available The catalytic loop HRD motif is found in most protein kinases and these amino acids are predicted to perform functions in catalysis, transition to, and stabilization of the active conformation of the kinase domain. We have identified mutations in a Drosophila src gene, src64, that alter the three HRD amino acids. We have analyzed the mutants for both biochemical activity and biological function during development. Mutation of the aspartate to asparagine eliminates biological function in cytoskeletal processes and severely reduces fertility, supporting the amino acid's critical role in enzymatic activity. The arginine to cysteine mutation has little to no effect on kinase activity or cytoskeletal reorganization, suggesting that the HRD arginine may not be critical for coordinating phosphotyrosine in the active conformation. The histidine to leucine mutant retains some kinase activity and biological function, suggesting that this amino acid may have a biochemical function in the active kinase that is independent of its side chain hydrogen bonding interactions in the active site. We also describe the phenotypic effects of other mutations in the SH2 and tyrosine kinase domains of src64, and we compare them to the phenotypic effects of the src64 null allele.

  2. Alterations in interhemispheric functional and anatomical connectivity are associated with tobacco smoking in humans.

    Science.gov (United States)

    Viswanath, Humsini; Velasquez, Kenia M; Thompson-Lake, Daisy Gemma Yan; Savjani, Ricky; Carter, Asasia Q; Eagleman, David; Baldwin, Philip R; De La Garza, Richard; Salas, Ramiro

    2015-01-01

    Abnormal interhemispheric functional connectivity correlates with several neurologic and psychiatric conditions, including depression, obsessive-compulsive disorder, schizophrenia, and stroke. Abnormal interhemispheric functional connectivity also correlates with abuse of cannabis and cocaine. In the current report, we evaluated whether tobacco abuse (i.e., cigarette smoking) is associated with altered interhemispheric connectivity. To that end, we examined resting state functional connectivity (RSFC) using magnetic resonance imaging (MRI) in short term tobacco deprived and smoking as usual tobacco smokers, and in non-smoker controls. Additionally, we compared diffusion tensor imaging (DTI) in the same subjects to study differences in white matter. The data reveal a significant increase in interhemispheric functional connectivity in sated tobacco smokers when compared to controls. This difference was larger in frontal regions, and was positively correlated with the average number of cigarettes smoked per day. In addition, we found a negative correlation between the number of DTI streamlines in the genual corpus callosum and the number of cigarettes smoked per day. Taken together, our results implicate changes in interhemispheric functional and anatomical connectivity in current cigarette smokers.

  3. Alterations of Functional Connectivity Among Resting-State Networks in Hypothyroidism.

    Science.gov (United States)

    Singh, S; Kumar, M; Modi, S; Kaur, P; Shankar, L R; Khushu, S

    2015-07-01

    Hypothyroidism affects brain functioning as suggested by various neuroimaging studies. The primary focus of the present study was to examine whether hypothyroidism would impact connectivity among resting-state networks (RSNs) using resting-state functional magnetic resonance imaging (rsfMRI). Twenty-two patients with hypothyroidism and 22 healthy controls were recruited and scanned using rsfMRI. The data were analysed using independent component analysis and a dual regression approach that was applied on five RSNs that were identified using fsl software (http://fsl.fmrib.ox.ac.uk). Hypothyroid patients showed significantly decreased functional connectivity in the regions of the right frontoparietal network (frontal pole), the medial visual network (lateral occipital gyrus, precuneus cortex and cuneus) and the motor network (precentral gyrus, postcentral gyrus, precuneus cortex, paracingulate gyrus, cingulate gyrus and supramarginal gyrus) compared to healthy controls. The reduced functional connectivity in the right frontoparietal network, the medial visual network and the motor network suggests neurocognitive alterations in hypothyroid patients in the corresponding functions. However, the study would be further continued to investigate the effects of thyroxine treatment and correlation with neurocognitive scores. The findings of the present study provide further interesting insights into our understanding of the action of thyroid hormone on the adult human brain.

  4. Cardiovascular Deconditioning in Humans: Alteration in Cardiovascular Regulation and Function During Simulated Microgravity

    Science.gov (United States)

    Cohen, Richard

    1999-01-01

    Alterations in cardiovascular regulation and function that occur during and after space flight have been reported. These alterations are manifested, for example, by reduced orthostatic tolerance upon reentry to the earth's gravity from space. However, the precise physiologic mechanisms responsible for these alterations remain to be fully elucidated. Perhaps, as a result, effective countermeasures have yet to be developed. In this project we apply a powerful, new method - cardiovascular system identification (CSI) - for the study of the effects of space flight on the cardiovascular system so that effective countermeasures can be developed. CSI involves the mathematical analysis of second-to-second fluctuations in non-invasively measured heart rate, arterial blood pressure (ABP), and instantaneous lung volume (ILV - respiratory activity) in order to characterize quantitatively the physiologic mechanisms responsible for the couplings between these signals. Through the characterization of all the physiologic mechanisms coupling these signals, CSI provides a model of the closed-loop cardiovascular regulatory state in an individual subject. The model includes quantitative descriptions of the heart rate baroreflex, autonomic function, as well as other important physiologic mechanisms. We are in the process of incorporating beat-to-beat fluctuations of stroke volume into the CSI technique in order to quantify additional physiologic mechanisms such as those involved in control of peripheral vascular resistance and alterations in cardiac contractility. We apply CSI in conjunction with the two general protocols of the Human Studies Core project. The first protocol involves ground-based, human head down tilt bed rest to simulate microgravity and acute stressors - upright tilt, standing and bicycle exercise - to provide orthostatic and exercise challenges. The second protocol is intended to be the same as the first but with the addition of sleep deprivation to determine whether

  5. Altered amygdala resting-state functional connectivity in post-traumatic stress disorder

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    Christine Anne Rabinak

    2011-11-01

    Full Text Available Post-traumatic stress disorder (PTSD is often characterized by aberrant amygdala activation and functional abnormalities in corticolimbic circuitry, as elucidated by functional neuroimaging. These ‘activation’ studies have primarily relied on tasks designed to induce region-specific, and task-dependent brain responses in limbic (e.g., amygdala and paralimbic brain areas through the use of evocative probes such as personalized traumatic script-driven imagery and other negatively valenced emotional stimuli (e.g., threatening faces, aversive scenes, traumatic cues. It remains unknown if these corticolimbic circuit abnormalities exist at baseline or ‘at rest’, in the absence of fear/anxiety-related provocation and outside the context of task demands. Recently, a new approach to studying functional interconnectivity of brain regions derived from ‘resting state’ scans has elucidated systems-level neural network function that may be obscured by activation tasks and may help inform functional interpretations of brain activation patterns. Little is known about whether altered amygdala connectivity patterns exist at rest in PTSD. Therefore the primary aim of the present experiment was to investigate aberrant amygdala functional connectivity patterns in combat-related PTSD patients during resting state. Seventeen Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF veterans with combat-related PTSD (PTSD group and seventeen combat-exposed OEF/OIF veterans without PTSD (Combat-Exposed Control [CEC] group underwent an 8-minute resting-state functional magnetic resonance imaging scan. Using conventional methods to generate connectivity maps, we extracted the time series from an anatomically-derived amygdala ‘seed’ region and conducted voxel-wise correlation analyses across the entire brain to search for group differences (between PTSD and CEC groups in amygdala functional connectivity, which we hypothesized would localize to the medial

  6. Altered resting-state functional connectivity in cortical networks in psychopathy.

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    Philippi, Carissa L; Pujara, Maia S; Motzkin, Julian C; Newman, Joseph; Kiehl, Kent A; Koenigs, Michael

    2015-04-15

    Psychopathy is a personality disorder characterized by callous antisocial behavior and criminal recidivism. Here we examine whether psychopathy is associated with alterations in functional connectivity in three large-scale cortical networks. Using fMRI in 142 adult male prison inmates, we computed resting-state functional connectivity using seeds from the default mode network, frontoparietal network, and cingulo-opercular network. To determine the specificity of our findings to these cortical networks, we also calculated functional connectivity using seeds from two comparison primary sensory networks: visual and auditory networks. Regression analyses related network connectivity to overall psychopathy scores and to subscores for the "factors" and "facets" of psychopathy: Factor 1, interpersonal/affective traits; Factor 2, lifestyle/antisocial traits; Facet 1, interpersonal; Facet 2, affective; Facet 3, lifestyle; Facet 4, antisocial. Overall psychopathy severity was associated with reduced functional connectivity between lateral parietal cortex and dorsal anterior cingulate cortex. The two factor scores exhibited contrasting relationships with functional connectivity: Factor 1 scores were associated with reduced functional connectivity in the three cortical networks, whereas Factor 2 scores were associated with heightened connectivity in the same networks. This dissociation was evident particularly in the functional connectivity between anterior insula and dorsal anterior cingulate cortex. The facet scores also demonstrated distinct patterns of connectivity. We found no associations between psychopathy scores and functional connectivity within visual or auditory networks. These findings provide novel evidence on the neural correlates of psychopathy and suggest that connectivity between cortical association hubs, such as the dorsal anterior cingulate cortex, may be a neurobiological marker of the disorder.

  7. Altered distributions of bone tissue mineral and collagen properties in women with fragility fractures.

    Science.gov (United States)

    Wang, Zhen Xiang; Lloyd, Ashley A; Burket, Jayme C; Gourion-Arsiquaud, Samuel; Donnelly, Eve

    2016-03-01

    Heterogeneity of bone tissue properties is emerging as a potential indicator of altered bone quality in pathologic tissue. The objective of this study was to compare the distributions of tissue properties in women with and without histories of fragility fractures using Fourier transform infrared (FTIR) imaging. We extended a prior study that examined the relationship of the mean FTIR properties to fracture risk by analyzing in detail the widths and the tails of the distributions of FTIR properties in biopsies from fracture and non-fracture cohorts. The mineral and matrix properties of cortical and trabecular iliac crest tissue were compared in biopsies from women with a history of fragility fracture (+Fx; n=21, age: mean 54±SD 15y) and with no history of fragility fracture (-Fx; n=12, age: 57±5y). A subset of the patients included in the -Fx group were taking estrogen-plus-progestin hormone replacement therapy (HRT) (-Fx+HRT n=8, age: 58±5y) and were analyzed separately from patients with no history of HRT (-Fx-HRT n=4, age: 56±7y). When the FTIR parameter mean values were examined by treatment group, the trabecular tissue of -Fx-HRT patients had a lower mineral:matrix ratio (M:M) and collagen maturity (XLR) than that of -Fx+HRT patients (-22% M:M, -18% XLR) and +Fx patients (-17% M:M, -18% XLR). Across multiple FTIR parameters, tissue from the -Fx-HRT group had smaller low-tail (5th percentile) values than that from the -Fx+HRT or +Fx groups. In trabecular collagen maturity and crystallinity (XST), the -Fx-HRT group had smaller low-tail values than those in the -Fx+HRT group (-16% XLR, -5% XST) and the +Fx group (-17% XLR, -7% XST). The relatively low values of trabecular mineral:matrix ratio and collagen maturity and smaller low-tail values of collagen maturity and crystallinity observed in the -Fx-HRT group are characteristic of younger tissue. Taken together, our data suggest that the presence of newly formed tissue that includes small/imperfect crystals

  8. Yellow Mealworm Protein for Food Purposes - Extraction and Functional Properties.

    Directory of Open Access Journals (Sweden)

    Xue Zhao

    Full Text Available A protocol for extraction of yellow mealworm larvae proteins was established, conditions were evaluated and the resulting protein extract was characterised. The freeze-dried yellow mealworm larvae contained around 33% fat, 51% crude protein and 43% true protein on a dry matter basis. The true protein content of the protein extract was about 75%, with an extraction rate of 70% under optimised extraction conditions using 0.25 M NaOH, a NaOH solution:ethanol defatted worm ratio of 15:1 mL/g, 40°C for 1 h and extraction twice. The protein extract was a good source of essential amino acids. The lowest protein solubility in distilled water solution was found between pH 4 and 5, and increased with either increasing or decreasing pH. Lower solubility was observed in 0.5 M NaCl solution compared with distilled water. The rheological tests indicated that temperature, sample concentration, addition of salt and enzyme, incubation time and pH alterations influenced the elastic modulus of yellow mealworm protein extract (YMPE. These results demonstrate that the functional properties of YMPE can be modified for different food applications.

  9. Yellow Mealworm Protein for Food Purposes - Extraction and Functional Properties.

    Science.gov (United States)

    Zhao, Xue; Vázquez-Gutiérrez, José Luis; Johansson, Daniel P; Landberg, Rikard; Langton, Maud

    2016-01-01

    A protocol for extraction of yellow mealworm larvae proteins was established, conditions were evaluated and the resulting protein extract was characterised. The freeze-dried yellow mealworm larvae contained around 33% fat, 51% crude protein and 43% true protein on a dry matter basis. The true protein content of the protein extract was about 75%, with an extraction rate of 70% under optimised extraction conditions using 0.25 M NaOH, a NaOH solution:ethanol defatted worm ratio of 15:1 mL/g, 40°C for 1 h and extraction twice. The protein extract was a good source of essential amino acids. The lowest protein solubility in distilled water solution was found between pH 4 and 5, and increased with either increasing or decreasing pH. Lower solubility was observed in 0.5 M NaCl solution compared with distilled water. The rheological tests indicated that temperature, sample concentration, addition of salt and enzyme, incubation time and pH alterations influenced the elastic modulus of yellow mealworm protein extract (YMPE). These results demonstrate that the functional properties of YMPE can be modified for different food applications.

  10. Altered small-world efficiency of brain functional networks in acupuncture at ST36: a functional MRI study.

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    Bo Liu

    Full Text Available BACKGROUND: Acupuncture in humans can produce clinical effects via the central nervous system. However, the neural substrates of acupuncture's effects remain largely unknown. RESULTS: We utilized functional MRI to investigate the topological efficiency of brain functional networks in eighteen healthy young adults who were scanned before and after acupuncture at the ST36 acupoints (ACUP and its sham point (SHAM. Whole-brain functional networks were constructed by thresholding temporal correlations matrices of ninety brain regions, followed by a graph theory-based analysis. We showed that brain functional networks exhibited small-world attributes (high local and global efficiency regardless of the order of acupuncture and stimulus points, a finding compatible with previous studies of brain functional networks. Furthermore, the brain networks had increased local efficiency after ACUP stimulation but there were no significant differences after SHAM, indicating a specificity of acupuncture point in coordinating local information flow over the whole brain. Moreover, significant (P<0.05, corrected by false discovery rate approach effects of only acupuncture point were detected on nodal degree of the left hippocampus (higher nodal degree at ACUP as compared to SHAM. Using an uncorrected P<0.05, point-related effects were also observed in the anterior cingulate cortex, frontal and occipital regions while stimulation-related effects in various brain regions of frontal, parietal and occipital cortex regions. In addition, we found that several limbic and subcortical brain regions exhibited point- and stimulation-related alterations in their regional homogeneity (P<0.05, uncorrected. CONCLUSIONS: Our results suggest that acupuncture modulates topological organization of whole-brain functional brain networks and the modulation has point specificity. These findings provide new insights into neuronal mechanism of acupuncture from the perspective of functional

  11. Differences in functional brain connectivity alterations associated with cerebral amyloid deposition in amnestic mild cognitive impairment

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    Dahyun eYi

    2015-02-01

    Full Text Available Despite potential implications for the early detection of impending AD, very little is known about the differences of large scale brain networks between amnestic MCI (aMCI with high cerebral amyloid beta protein (Aβ deposition (i.e., aMCI+ and aMCI with no or very little Aβ deposition (i.e., aMCI-. We first aimed to extend the current literature on altering intrinsic functional connectivity (FC of the default mode network (DMN and salience network (SN from CN to AD dementia. Second, we further examined the differences of the DMN and the SN between aMCI-, aMCI+, and CN. Forty-three older adult (12 CN, 10 aMCI+, 10 aMCI-, and 11 AD dementia subjects were included. All participants received clinical and neuropsychological assessment, resting state functional MRI, structural MRI, and Pittsburgh compound-B-PET scans. FC data were preprocessed using Multivariate Exploratory Linear Optimized Decomposition into Independent Components of FSL. Group comparisons were carried out using the dual-regression approach. In addition, to verify presence of grey matter (GM volume changes with intrinsic functional network alterations, Voxel Based Morphometry was performed on the acquired T1-weighted data. As expected, AD dementia participants exhibited decreased FC in the DMN compared to CN (in precuneus and cingulate gyrus. The degree of alteration in the DMN in aMCI+ compared to CN was intermediate to that of AD. In contrast, aMCI- exhibited increased FC in the DMN compared to CN (in precuneus as well as aMCI+. In terms of the SN, aMCI- exhibited decreased FC compared to both CN and aMCI+ particularly in the inferior frontal gyrus. FC within the SN in aMCI+ and AD did not differ from CN. Compared to CN, aMCI- showed atrophy in bilateral superior temporal gyri whereas aMCI+ showed atrophy in right precuneus. The results indicate that despite of the similarity in cross-sectional cognitive features aMCI- has quite different functional brain connectivity compared to

  12. Functional properties of α-lactalbumin and β-lactoglobulin

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    Zoran Herceg

    2004-06-01

    Full Text Available Whey proteins are commonly used in the food industry due to their nutritive value and functional properties. The most important functional properties of whey proteins are solubility, viscosity, water holding capacity, emulsification and foaming. The aim of this study was to determine functional properties of main whey protein fractions (α-lactalbumin and β-lactoglobulin which have the biggest influence on the functional properties of whey proteins. Particle size analysis and specific area of α-lactalbumin and β-lactoglobulin were performed by «Mie – theory» of «light scatering» using «Malvern Mastersizer X». The results of this analysis have shown that β-lactoglobulin had higher particle size and specific area than α-lactalbumin.By examining functional properties (solubility, dispersibility, emulsifiying properties – emulsion activity index (EAI and emulsion stability index (ESI and foaming properties of α-lactalbumin and β-lactoglobulin, it has been established that β-lactoglobulin has higher solubility, dispersibility, emulsifiying properties as well as foaming properties than α-lactalbumin. Rheological properties of protein suspensions were determined by rotational viscosimeter, Brookfiel DV-III at temperature 25°C. Rheological parameters, flow behavior indeks (n and consistency coefficient (k were determined by the power-law model. The results of investigation have shown that 10% suspenzion of α-lactalbumin and β-lactoglobulin are non-Newtonian fluids and they exhibited pseudoplastic properties.

  13. [The value of double contrast arthrotomography combined with cinematography in the diagnosis of functional and structural TMJ alterations].

    Science.gov (United States)

    Engelke, W; Grossniklaus, B; Sailer, H F

    1991-01-01

    Double contrast arthrotomography combined with cinematography as a diagnostic instrument establishing functional and structural TMJ alterations is evaluated for its diagnostic value and reliability within the chain of diagnostic measures applied. In 131 patients double-contrast arthrotomography was followed by a comprehensive history of joint problems, and verification of the clinical findings as well as the arthrographic diagnosis and the post-arthrographic TMJ alterations. Our interest was focussed, among others, on the question whether arthrography alone would have any therapeutic effect or produce an alteration in TMJ function.

  14. Assessment of Cardiac Functional Alterations of Ankylosing Spondylitis Patients without Cardiovascular Risk Factors

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    Alper Kepez

    2013-08-01

    Full Text Available Introduction: The aim of this study is to evaluate cardiac functional alterations of ankylosing spondylitis patients without any cardiovascular risk factors.Patients and Methods: Thirty seven consecutive akylosing spondylitis patients without any cardiovascular risk factors constituted our study patient population (age: 41.4 ± 11.1 years, 28 male. Electrocardiographs (ECG of all patients were obtained and all patients underwent comprehensive transthoracic echocardiographic examination. QRS durations, p wave dispersion and corrected QT dispersion (QTcd values were calculated from 12-lead ECG’s. Data reflecting left ventricular systolic and diastolic functions were obtained from echocardiographic examinations. Data of patients were compared with the data of 28 age-and gender matched healthy control subjects (age: 40.1 ± 10.5 years, 19 male.Results: There were no significant differences between patients and controls regarding QRS durations, p wave dispersion and QTcd values. There were also no significant differences between patients and controls regarding parameters reflecting left ventricular systolic and diastolic functions. Annular velocities at mitral and tricuspid annulus levels evaluated with pulsed-wave tissue Doppler imaging were also similar as well. Two (7.2% subjects in the control group and 2 (5.4% patients in the akylosing spondylitis group had minimal aortic regurgitation (p= 0.51. Conclusion: We could not demonstrate any electrocardiographic or echocardiographic evidence of structural myocardial alterations in a small sample of akylosing spondylitis patients free of cardiovascular risk factors. Effects of frequently encountered co-existent cardiovascular risk factors of ankylosing spondylitis patients might have contributed to the conflicting literature data related with this topic.

  15. Altered default network resting-state functional connectivity in adolescents with Internet gaming addiction.

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    Wei-na Ding

    Full Text Available PURPOSE: Excessive use of the Internet has been linked to a variety of negative psychosocial consequences. This study used resting-state functional magnetic resonance imaging (fMRI to investigate whether functional connectivity is altered in adolescents with Internet gaming addiction (IGA. METHODS: Seventeen adolescents with IGA and 24 normal control adolescents underwent a 7.3 minute resting-state fMRI scan. Posterior cingulate cortex (PCC connectivity was determined in all subjects by investigating synchronized low-frequency fMRI signal fluctuations using a temporal correlation method. To assess the relationship between IGA symptom severity and PCC connectivity, contrast images representing areas correlated with PCC connectivity were correlated with the scores of the 17 subjects with IGA on the Chen Internet Addiction Scale (CIAS and Barratt Impulsiveness Scale-11 (BIS-11 and their hours of Internet use per week. RESULTS: There were no significant differences in the distributions of the age, gender, and years of education between the two groups. The subjects with IGA showed longer Internet use per week (hours (p<0.0001 and higher CIAS (p<0.0001 and BIS-11 (p = 0.01 scores than the controls. Compared with the control group, subjects with IGA exhibited increased functional connectivity in the bilateral cerebellum posterior lobe and middle temporal gyrus. The bilateral inferior parietal lobule and right inferior temporal gyrus exhibited decreased connectivity. Connectivity with the PCC was positively correlated with CIAS scores in the right precuneus, posterior cingulate gyrus, thalamus, caudate, nucleus accumbens, supplementary motor area, and lingual gyrus. It was negatively correlated with the right cerebellum anterior lobe and left superior parietal lobule. CONCLUSION: Our results suggest that adolescents with IGA exhibit different resting-state patterns of brain activity. As these alterations are partially consistent with those in patients

  16. Detection of alterations in testicular and epididymal function in laboratory animals

    Energy Technology Data Exchange (ETDEWEB)

    Amann, R.P.

    1986-12-01

    The potential impact of an agent altering male reproductive function is greater for humans than for animals. Consequently, it is essential that sensitive criteria be used to look for effects on a multiplicity of target sites when an agent is evaluated using an animal model. No animal model has reproductive characteristics similar to those of humans, but this does not negate the validity of using animal models. Classic methodologies for reproductive toxicology are limited by the approaches used for subjective evaluation of testicular histology and use of natural mating for fertility tests. After dosing for an interval at least equal to six times the duration of one cycle of the seminiferous epithelium, sperm from ejaculated semen or the cauda epididymidis can be evaluated for normalacy of morphology or function and should be used for artificial insemination of females to critically evaluate fertility. Normal males of animals models ejaculate a great excess of sperm. Artificial insemination of a critical number of sperm, selected to result in slightly less than maximal fertility for control animals, will maximize the probability of detecting a decrease in fertility if the same critical number of sperm is inseminated for treated animals as for control animals. Testicular function should be evaluated by objective, rather than subjective, criteria. Among the more sensitive criteria of testicular function are the minor diameter of essentially round seminiferous tubules, the ratio of leptotene spermatocytes to Sertoli cells, the corrected numbers of germ cells per seminiferous tubule cross section, and the number of homogenization-resistant spermatids per testis.

  17. Diet-Induced Weight Loss Alters Functional Brain Responses during an Episodic Memory Task

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    Carl-Johan Boraxbekk

    2015-07-01

    Full Text Available Objective: It has been suggested that overweight is negatively associated with cognitive functions. The aim of this study was to investigate whether a reduction in body weight by dietary interventions could improve episodic memory performance and alter associated functional brain responses in overweight and obese women. Methods: 20 overweight postmenopausal women were randomized to either a modified paleolithic diet or a standard diet adhering to the Nordic Nutrition Recommendations for 6 months. We used functional magnetic resonance imaging to examine brain function during an episodic memory task as well as anthropometric and biochemical data before and after the interventions. Results: Episodic memory performance improved significantly (p = 0.010 after the dietary interventions. Concomitantly, brain activity increased in the anterior part of the right hippocampus during memory encoding, without differences between diets. This was associated with decreased levels of plasma free fatty acids (FFA. Brain activity increased in pre-frontal cortex and superior/middle temporal gyri. The magnitude of increase correlated with waist circumference reduction. During episodic retrieval, brain activity decreased in inferior and middle frontal gyri, and increased in middle/superior temporal gyri. Conclusions: Diet-induced weight loss, associated with decreased levels of plasma FFA, improves episodic memory linked to increased hippocampal activity.

  18. Does Acupuncture Alter Pain-related Functional Connectivity of the Central Nervous System? A Systematic Review.

    Science.gov (United States)

    Villarreal Santiago, María; Tumilty, Steve; Mącznik, Aleksandra; Mani, Ramakrishnan

    2016-08-01

    Acupuncture has been studied for several decades to establish evidence-based clinical practice. This systematic review aims to evaluate evidence for the effectiveness of acupuncture in influencing the functional connectivity of the central nervous system in patients with musculoskeletal pain. A systematic search of the literature was conducted to identify studies in which the central response of acupuncture in patients with musculoskeletal pain was evaluated by neuroimaging techniques. Databases searched were AMED, CINAHL, Cochrane Library, EMBASE, MEDLINE, PEDro, Pubmed, SCOPUS, SPORTDiscuss, and Web of Science. Included studies were assessed by two independent reviewers for their methodological quality by using the Downs and Black questionnaire and for their levels of completeness and transparency in reporting acupuncture interventions by using Standards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA) criteria. Seven studies met the inclusion criteria. Three studies were randomized controlled trials (RCTs) and four studies were nonrandomized controlled trials (NRCTs). The neuroimaging techniques used were functional magnetic resonance imaging (fMRI) and positron emission tomography (PET). Positive effects on the functional connectivity of the central nervous system more consistently occurred during long-term acupuncture treatment. The results were heterogeneous from a descriptive perspective; however, the key findings support acupuncture's ability to alter pain-related functional connectivity in the central nervous system in patients with musculoskeletal pain.

  19. Altered right ventricular contractile pattern after cardiac surgery: monitoring of septal function is essential.

    Science.gov (United States)

    Nguyen, Tin; Cao, Long; Movahed, Assad

    2014-10-01

    Assessment of right ventricular (RV) function is important in the management of various forms of cardiovascular disease. Accurately assessing RV volume and systolic function is a challenge in day-to-day clinical practice due to its complex geometry. Tricuspid annular plane systolic excursion (TAPSE) and systolic excursion velocity (S') have been reviewed to further assess their suitability and objectivity in evaluating RV function. Multiple studies have validated their diagnostic and prognostic values in numerous pathologic conditions. Diminished longitudinal contraction after cardiothoracic surgery is a well-known phenomenon, but it is not well validated. Despite significant reduction in RV performance along the long-axis assessed by TAPSE and S' after cardiac surgery, RV ejection fractions did not change as well as the left ventricular parameters and exercise capacity. RV contractile patterns were markedly altered with decreased longitudinal shortening and increased transverse shortening, which are likely resulted from the septal damage during cardiac surgery. The septum is essential for RV performance due to its oblique fiber orientation. This allows ventricular twisting, which is a vital mechanism against increased pulmonary vascular resistance. The septum function along with TAPSE and S' should be adequately assessed during cardiac surgery, and evidence of septal dysfunction should lead to reevaluation of myocardial protection methods.

  20. Mechanisms driving change: altered species interactions and ecosystem function through global warming.

    Science.gov (United States)

    Traill, Lochran W; Lim, Matthew L M; Sodhi, Navjot S; Bradshaw, Corey J A

    2010-09-01

    1. We review the mechanisms behind ecosystem functions, the processes that facilitate energy transfer along food webs, and the major processes that allow the cycling of carbon, oxygen and nitrogen, and use case studies to show how these have already been, and will continue to be, altered by global warming. 2. Increased temperatures will affect the interactions between heterotrophs and autotrophs (e.g. pollination and seed dispersal), and between heterotrophs (e.g. predators-prey, parasites/pathogens-hosts), with generally negative ramifications for important ecosystem services (functions that provide direct benefit to human society such as pollination) and potential for heightened species co-extinction rates. 3. Mitigation of likely impacts of warming will require, in particular, the maintenance of species diversity as insurance for the provision of basic ecosystem services. Key to this will be long-term monitoring and focused research that seek to maintain ecosystem resilience in the face of global warming. 4. We provide guidelines for pursuing research that quantifies the nexus between ecosystem function and global warming. These include documentation of key functional species groups within systems, and understanding the principal outcomes arising from direct and indirect effects of a rapidly warming environment. Localized and targeted research and monitoring, complemented with laboratory work, will determine outcomes for resilience and guide adaptive conservation responses and long-term planning.

  1. Properties of generalized univariate hypergeometric functions

    NARCIS (Netherlands)

    van de Bult, F.J.; Rains, E.M.; Stokman, J.V.

    2007-01-01

    Abstract: Based on Spiridonov’s analysis of elliptic generalizations of the Gauss hypergeometric function, we develop a common framework for 7-parameter families of generalized elliptic, hyperbolic and trigonometric univariate hypergeometric functions. In each case we derive the symmetries of the ge

  2. Altered functional connectivity of the language network in ASD: Role of classical language areas and cerebellum

    Directory of Open Access Journals (Sweden)

    Marjolein Verly

    2014-01-01

    Full Text Available The development of language, social interaction and communicative skills is remarkably different in the child with autism spectrum disorder (ASD. Atypical brain connectivity has frequently been reported in this patient population. However, the neural correlates underlying their disrupted language development and functioning are still poorly understood. Using resting state fMRI, we investigated the functional connectivity properties of the language network in a group of ASD patients with clear comorbid language impairment (ASD-LI; N = 19 and compared them to the language related connectivity properties of 23 age-matched typically developing children. A verb generation task was used to determine language components commonly active in both groups. Eight joint language components were identified and subsequently used as seeds in a resting state analysis. Interestingly, both the interregional and the seed-based whole brain connectivity analysis showed preserved connectivity between the classical intrahemispheric language centers, Wernicke's and Broca's areas. In contrast however, a marked loss of functional connectivity was found between the right cerebellar region and the supratentorial regulatory language areas. Also, the connectivity between the interhemispheric Broca regions and modulatory control dorsolateral prefrontal region was found to be decreased. This disruption of normal modulatory control and automation function by the cerebellum may underlie the abnormal language function in children with ASD-LI.

  3. Morphological and functional alterations in adult boar epididymis: Effects of prenatal and postnatal administration of flutamide

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    Chojnacka Katarzyna

    2011-02-01

    Full Text Available Abstract Background The dynamic cross-talk between epididymal cells is hormonally regulated and, in part, through direct cell-to-cell interactions. To date, no information is available regarding possible impact of anti-androgens on the proteins involved in the gap junctional communication within the boar epididymis. Thus, a question arised whether prenatal or postnatal exposure to an anti-androgen flutamide alters the expression of gap junction protein - connexin43 (Cx43 and androgen receptor (AR expression in the caput, corpus and cauda epididymis and leads to delayed effects on morphology and function of adult pig epididymis. Methods First two experimental groups received flutamide prenatally on gestational days 20-28 and 80-88 (GD20 and GD80 and further two groups were exposed to flutamide postanatally on days 2-10 and 90-98 after birth (PD2 and PD90. Epididymides were collected from adult boars. Routine histology was performed using hematoxylin-eosin staining. The expression of Cx43 and AR were analyzed using immunohistochemistry and Western blotting. Both analyses were supported by quantitative approaches to demonstrate the variations of the expression levels following the treatment. Apoptotic cells were identified using TUNEL assay. Results Histological examination revealed differences in epididymal morphology of flutamide-exposed boars when compared to controls. Scarce spermatic content were seen within the corpus and cauda lumina of GD20, PD2 and PD90 groups. Concomitantly, frequency of epididymal cell apoptosis was significantly higher (p p p p Conclusions The region-specific alterations in the epididymis morphology and scarce spermatic content within the lumina of the corpus and cauda indicate that flutamide can induce delayed effects on the epididymal function of the adult boar by decrease in AR protein levels that results in altered androgen signaling. This may cause disturbances in androgen-dependent processes including Cx43

  4. Effects of altered catecholamine metabolism on pigmentation and physical properties of sclerotized regions in the silkworm melanism mutant.

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    Liang Qiao

    Full Text Available Catecholamine metabolism plays an important role in the determination of insect body color and cuticle sclerotization. To date, limited research has focused on these processes in silkworm. In the current study, we analyzed the interactions between catecholamines and melanin genes and their effects on the pigmentation patterns and physical properties of sclerotized regions in silkworm, using the melanic mutant melanism (mln silkworm strain as a model. Injection of β-alanine into mln mutant silkworm induced a change in catecholamine metabolism and turned its body color yellow. Further investigation of the catecholamine content and expression levels of the corresponding melanin genes from different developmental stages of Dazao-mln (mutant and Dazao (wild-type silkworm revealed that at the larval and adult stages, the expression patterns of melanin genes precipitated dopamine accumulation corresponding to functional loss of Bm-iAANAT, a repressive effect of excess NBAD on ebony, and upregulation of tan in the Dazao-mln strain. During the early pupal stage, dopamine did not accumulate in Dazao-mln, since upregulation of ebony and black genes led to conversion of high amounts of dopamine into NBAD, resulting in deep yellow cuticles. Scanning electron microscope analysis of a cross-section of adult dorsal plates from both wild-type and mutant silkworm disclosed the formation of different layers in Dazao-mln owing to lack of NADA, compared to even and dense layers in Dazao. Analysis of the mechanical properties of the anterior wings revealed higher storage modulus and lower loss tangent in Dazao-mln, which was closely associated with the altered catecholamine metabolism in the mutant strain. Based on these findings, we conclude that catecholamine metabolism is crucial for the color pattern and physical properties of cuticles in silkworm. Our results should provide a significant contribution to Lepidoptera cuticle tanning research.

  5. Aging alters functionally human dermal papillary fibroblasts but not reticular fibroblasts: a new view of skin morphogenesis and aging.

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    Solène Mine

    Full Text Available Understanding the contribution of the dermis in skin aging is a key question, since this tissue is particularly important for skin integrity, and because its properties can affect the epidermis. Characteristics of matched pairs of dermal papillary and reticular fibroblasts (Fp and Fr were investigated throughout aging, comparing morphology, secretion of cytokines, MMPs/TIMPs, growth potential, and interaction with epidermal keratinocytes. We observed that Fp populations were characterized by a higher proportion of small cells with low granularity and a higher growth potential than Fr populations. However, these differences became less marked with increasing age of donors. Aging was also associated with changes in the secretion activity of both Fp and Fr. Using a reconstructed skin model, we evidenced that Fp and Fr cells do not possess equivalent capacities to sustain keratinopoiesis. Comparing Fp and Fr from young donors, we noticed that dermal equivalents containing Fp were more potent to promote epidermal morphogenesis than those containing Fr. These data emphasize the complexity of dermal fibroblast biology and document the specific functional properties of Fp and Fr. Our results suggest a new model of skin aging in which marked alterations of Fp may affect the histological characteristics of skin.

  6. Alterations in the functional neural circuitry supporting flexible choice behavior in autism spectrum disorders

    Science.gov (United States)

    D'Cruz, A-M; Mosconi, M W; Ragozzino, M E; Cook, E H; Sweeney, J A

    2016-01-01

    Restricted and repetitive behaviors, and a pronounced preference for behavioral and environmental consistency, are distinctive characteristics of autism spectrum disorder (ASD). Alterations in frontostriatal circuitry that supports flexible behavior might underlie this behavioral impairment. In an functional magnetic resonance imaging study of 17 individuals with ASD, and 23 age-, gender- and IQ-matched typically developing control participants, reversal learning tasks were used to assess behavioral flexibility as participants switched from one learned response choice to a different response choice when task contingencies changed. When choice outcome after reversal was uncertain, the ASD group demonstrated reduced activation in both frontal cortex and ventral striatum, in the absence of task performance differences. When the outcomes of novel responses were certain, there was no difference in brain activation between groups. Reduced activation in frontal cortex and ventral striatum suggest problems in decision-making and response planning, and in processing reinforcement cues, respectively. These processes, and their integration, are essential for flexible behavior. Alterations in these systems may therefore contribute to a rigid adherence to preferred behavioral patterns in individuals with an ASD. These findings provide an additional impetus for the use of reversal learning paradigms as a translational model for treatment development targeting the domain of restricted and repetitive behaviors in ASD. PMID:27727243

  7. Low oxygen alters mitochondrial function and response to oxidative stress in human neural progenitor cells

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    Yury M. Lages

    2015-12-01

    Full Text Available Oxygen concentration should be carefully regulated in all living tissues, beginning at the early embryonic stages. Unbalances in oxygen regulation can lead to cell death and disease. However, to date, few studies have investigated the consequences of variations in oxygen levels for fetal-like cells. Therefore, in the present work, human neural progenitor cells (NPCs derived from pluripotent stem cells grown in 3% oxygen (v/v were compared with NPCs cultured in 21% (v/v oxygen. Low oxygen concentrations altered the mitochondrial content and oxidative functions of the cells, which led to improved ATP production, while reducing generation of reactive oxygen species (ROS. NPCs cultured in both conditions showed no differences in proliferation and glucose metabolism. Furthermore, antioxidant enzymatic activity was not altered in NPCs cultured in 3% oxygen under normal conditions, however, when exposed to external agents known to induce oxidative stress, greater susceptibility to DNA damage was observed. Our findings indicate that the management of oxygen levels should be considered for in vitro models of neuronal development and drug screening.

  8. Cardio-protective role of terazosin is possibly mediated through alteration in thyroid function.

    Science.gov (United States)

    Jatwa, Rameshwar; Kar, Anand

    2006-12-03

    An investigation was made to reveal the possible involvement of thyroid hormones, if any, in terazosin (an alfa-1 adrenergic receptor blocker) induced alterations in tissue lipid peroxidation (LPO) and in the concentration of different serum lipids. We determined the impact of terazosin on the changes in hypercholesterolemic (CCT) diet induced thyroid dysfunction; cardiac, renal and hepatic LPO and on serum glucose concentration in female Wister rats. Simultaneously levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), creatinine, alkaline phosphatase (ALP) activity, hepatic glycogen synthesis and total daily food consumption were studied as supporting parameters. While a decrease in the level of serum thyroid hormones, HDL-C and in hepatic glycogen content, was observed in CCT diet fed animals; it increased the concentration of other serum lipids, glucose and creatinine; ALP activity; tissue and serum LPO. However, following terazosin administration for 15 days to CCT diet fed animals, status of thyroid hormones and all other thyroid dependent parameters were reversed suggesting that the drug might be acting through an alteration in the thyroid functions.

  9. Administration of MPTP to the common marmoset does not alter cortical cholinergic function

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    Garvey, J.; Petersen, M.; Waters, C.M.; Rose, S.P.; Hunt, S.; Briggs, R.; Jenner, P.; Marsden, C.D.

    1986-01-01

    The administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to common marmosets induced persistent motor deficits and decreased concentrations of dopamine, homovanillic acid, and 3,4-dihydroxy-phenylacetic acid (DOPAC) and (TH)dopamine uptake in the caudate-putamen. There was an 80% reduction in tyrosine hydroxylase immunoreactive cells in substantia nigra. At 10 days following the start of MPTP administration, the activity of choline acetyltransferase in the thalamus and frontal cortex was unchanged compared with control animals. Similarly, specific (TH)QNB binding was unaltered. At 4-6 weeks following the start of MPTP treatment, choline acetyltransferase activity and (TH)QNB binding in the frontal cortex and thalamus remained unaffected. There was no evidence for cell loss in the nucleus basalis of Meynert or alteration in the intensity of staining for acetylcholinesterase. MPTP treatment of the common marmoset produces a nigrostriatal lesion. In contrast, MPTP did not alter cortical cholinergic function and was not neurotoxic to the cholinergic cells in the nucleus basalis of Meynert.

  10. Cellulose nanocrystals: synthesis, functional properties, and applications

    OpenAIRE

    George J.; Sabapathi SN

    2015-01-01

    Johnsy George, SN Sabapathi Food Engineering and Packaging Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, India Abstract: Cellulose nanocrystals are unique nanomaterials derived from the most abundant and almost inexhaustible natural polymer, cellulose. These nanomaterials have received significant interest due to their mechanical, optical, chemical, and rheological properties. Cellulose nanocrystals primarily obtained from naturally occurring cellulose fibers...

  11. Functional properties of teff and oat composites

    Science.gov (United States)

    Teff-oat composites were developed using gluten free teff flour containing essential amino acids and minerals along with oat products containing ß-glucan known for lowering blood cholesterol. Teff-oat composites were evaluated for their pasting and rheological properties by a Rapid Visco Analyzer (R...

  12. Partial Decay of Thiamine Signal Transduction Pathway Alters Growth Properties of Candida glabrata

    Science.gov (United States)

    Shaik, Noor F.; Neal, Erin M.; Leone, Sarah G.; Cali, Brian J.; Peel, Michael T.; Grannas, Amanda M.; Wykoff, Dennis D.

    2016-01-01

    The phosphorylated form of thiamine (Vitamin B1), thiamine pyrophosphate (TPP) is essential for the metabolism of amino acids and carbohydrates in all organisms. Plants and microorganisms, such as yeast, synthesize thiamine de novo whereas animals do not. The thiamine signal transduction (THI) pathway in Saccharomyces cerevisiae is well characterized. The ~10 genes required for thiamine biosynthesis and uptake are transcriptionally upregulated during thiamine starvation by THI2, THI3, and PDC2. Candida glabrata, a human commensal and opportunistic pathogen, is closely related to S. cerevisiae but is missing half of the biosynthetic pathway, which limits its ability to make thiamine. We investigated the changes to the THI pathway in C. glabrata, confirming orthologous functions. We found that C. glabrata is unable to synthesize the pyrimidine subunit of thiamine as well as the thiamine precursor vitamin B6. In addition, THI2 (the gene encoding a transcription factor) is not present in C. glabrata, indicating a difference in the transcriptional regulation of the pathway. Although the pathway is upregulated by thiamine starvation in both species, C. glabrata appears to upregulate genes involved in thiamine uptake to a greater extent than S. cerevisiae. However, the altered regulation of the THI pathway does not alter the concentration of thiamine and its vitamers in the two species as measured by HPLC. Finally, we demonstrate potential consequences to having a partial decay of the THI biosynthetic and regulatory pathway. When the two species are co-cultured, the presence of thiamine allows C. glabrata to rapidly outcompete S. cerevisiae, while absence of thiamine allows S. cerevisiae to outcompete C. glabrata. This simplification of the THI pathway in C. glabrata suggests its environment provides thiamine and/or its precursors to cells, whereas S. cerevisiae is not as reliant on environmental sources of thiamine. PMID:27015653

  13. The functional properties, modification and utilization of whey proteins

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    B. G. Venter

    1986-03-01

    Full Text Available Whey protein has an excellent nutritional value and exhibits a functional potential. In comparison with certain other food proteins, the whey protein content of essential amino acids is extremely favourable for human consumption. Depending on the heat-treatment history thereof, soluble whey proteins with utilizable functional properties, apart from high biological value, true digestibility, protein efficiency ratio and nett protein utilization, can be recovered. Various technological and chemical recovery processes have been designed. Chemically and enzymatically modified whey protein is manufactured to obtain technological and functional advantages. The important functional properties of whey proteins, namely hydration, gelation, emulsifying and foaming properties, are reviewed.

  14. Soil microbial biomass and function are altered by 12 years of crop rotation

    Science.gov (United States)

    McDaniel, Marshall D.; Grandy, A. Stuart

    2016-11-01

    Declines in plant diversity will likely reduce soil microbial biomass, alter microbial functions, and threaten the provisioning of soil ecosystem services. We examined whether increasing temporal plant biodiversity in agroecosystems (by rotating crops) can partially reverse these trends and enhance soil microbial biomass and function. We quantified seasonal patterns in soil microbial biomass, respiration rates, extracellular enzyme activity, and catabolic potential three times over one growing season in a 12-year crop rotation study at the W. K. Kellogg Biological Station LTER. Rotation treatments varied from one to five crops in a 3-year rotation cycle, but all soils were sampled under a corn year. We hypothesized that crop diversity would increase microbial biomass, activity, and catabolic evenness (a measure of functional diversity). Inorganic N, the stoichiometry of microbial biomass and dissolved organic C and N varied seasonally, likely reflecting fluctuations in soil resources during the growing season. Soils from biodiverse cropping systems increased microbial biomass C by 28-112 % and N by 18-58 % compared to low-diversity systems. Rotations increased potential C mineralization by as much as 53 %, and potential N mineralization by 72 %, and both were related to substantially higher hydrolase and lower oxidase enzyme activities. The catabolic potential of the soil microbial community showed no, or slightly lower, catabolic evenness in more diverse rotations. However, the catabolic potential indicated that soil microbial communities were functionally distinct, and microbes from monoculture corn preferentially used simple substrates like carboxylic acids, relative to more diverse cropping systems. By isolating plant biodiversity from differences in fertilization and tillage, our study illustrates that crop biodiversity has overarching effects on soil microbial biomass and function that last throughout the growing season. In simplified agricultural systems

  15. High temperatures alter physiological properties of pyramidal cells and inhibitory interneurons in hippocampus

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    Jennifer eKim

    2012-07-01

    Full Text Available Temperature has multiple effects on neurons, yet little is known about the effects of high temperature on the physiology of mammalian central neurons. Hyperthermia can influence behavior and cause febrile seizures. We studied the effects of acute hyperthermia on the immature hippocampus in vitro by recording from pyramidal neurons and inhibitory oriens-lacunosum moleculare (O-LM interneurons (identified by green fluorescent protein expression in the GIN mouse line. Warming to 41°C caused depolarization, spontaneous action potentials, reduced input resistance and membrane time constant, and increased spontaneous synaptic activity of most pyramidal cells and O-LM interneurons. Pyramidal neurons of area CA3 were more strongly excited by hyperthermia than those of area CA1. About 90% of O-LM interneurons in both CA1 and CA3 increased their firing rates at hyperthermic temperatures; interneurons in CA3 fired faster than those in CA1 on average. Blockade of fast synaptic transmission did not abolish the effect of hyperthermia on neuronal excitability. Our results suggest that hyperthermia increases hippocampal excitability, particularly in seizure-prone area CA3, by altering the intrinsic membrane properties of pyramidal cells and interneurons.

  16. High temperatures alter physiological properties of pyramidal cells and inhibitory interneurons in hippocampus.

    Science.gov (United States)

    Kim, Jennifer A; Connors, Barry W

    2012-01-01

    Temperature has multiple effects on neurons, yet little is known about the effects of high temperature on the physiology of mammalian central neurons. Hyperthermia can influence behavior and cause febrile seizures. We studied the effects of acute hyperthermia on the immature hippocampus in vitro by recording from pyramidal neurons and inhibitory oriens-lacunosum moleculare (O-LM) interneurons (identified by green fluorescent protein (GFP) expression in the GIN mouse line). Warming to 41°C caused depolarization, spontaneous action potentials, reduced input resistance and membrane time constant, and increased spontaneous synaptic activity of most pyramidal cells and O-LM interneurons. Pyramidal neurons of area CA3 were more strongly excited by hyperthermia than those of area CA1. About 90% of O-LM interneurons in both CA1 and CA3 increased their firing rates at hyperthermic temperatures; interneurons in CA3 fired faster than those in CA1 on average. Blockade of fast synaptic transmission did not abolish the effect of hyperthermia on neuronal excitability. Our results suggest that hyperthermia increases hippocampal excitability, particularly in seizure-prone area CA3, by altering the intrinsic membrane properties of pyramidal cells and interneurons.

  17. Nutrient excess and altered mitochondrial proteome and function contribute to neurodegeneration in diabetes.

    Science.gov (United States)

    Chowdhury, Subir K Roy; Dobrowsky, Rick T; Fernyhough, Paul

    2011-11-01

    Diabetic neuropathy is a major complication of diabetes that results in the progressive deterioration of the sensory nervous system. Mitochondrial dysfunction has been proposed to play an important role in the pathogenesis of the neurodegeneration observed in diabetic neuropathy. Our recent work has shown that mitochondrial dysfunction occurs in dorsal root ganglia (DRG) sensory neurons in streptozotocin (STZ) induced diabetic rodents. In neurons, the nutrient excess associated with prolonged diabetes may trigger a switching off of AMP kinase (AMPK) and/or silent information regulator T1 (SIRT1) signaling leading to impaired peroxisome proliferator-activated receptor γ coactivator-1 (PGC-1α) expression/activity and diminished mitochondrial activity. This review briefly summarizes the alterations of mitochondrial function and proteome in sensory neurons of STZ-diabetic rodents. We also discuss the possible involvement of AMPK/SIRT/PGC-1α pathway in other diabetic models and different tissues affected by diabetes.

  18. Alteration of T cell function in healthy persons with a history of thymic x irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, C.H.L.; Kraft, S.C.; Rothberg, R.M.

    1975-10-01

    The possible late effects of x irradiation to the infantile thymus were investigated by studying immune functions in 12 healthy persons with a history of thymic x irradiation and healthy control subjects. No differences were found in serum immunoglobulin values, humoral antibody levels, lymphocyte counts, and lymphocyte reactivity to phytohemagglutinin, vaccinia virus, purified protein derivative (PPD), and allogeneic cells. The irradiation group exhibited cellular hyperresponsiveness to streptokinase-streptodornase (SK-SD). In contrast, mean skin and in vitro lymphocyte responses to Candida albicans were depressed in the patients with thymic irradiation. A dissociation of these two Candida responses was found in only 1 of 14 healthy control subjects but in 7 of 12 irradiated individuals. While thymic irradiation did not result in impaired immunologic defenses leading to clinical disease, it caused alterations in T cell responses similar to those reported in patients with chronic mucocutaneous candidiasis.

  19. Altered hippocampal function before emotional trauma in rats susceptible to PTSD-like behaviors.

    Science.gov (United States)

    Nalloor, Rebecca; Bunting, Kristopher M; Vazdarjanova, Almira

    2014-07-01

    Posttraumatic stress disorder (PTSD) is an anxiety disorder that occurs after experiencing a traumatic event. Susceptibility to PTSD exists, as only some trauma-exposed individuals develop this condition. Investigating susceptibilities in animal models can contribute to understanding the etiology of the disorder. We previously reported an animal model which allows reliable pre-classification of rats as susceptible (Sus) or resistant (Res) to developing a PTSD-like phenotype after a later trauma. Here we report that Sus, compared to Res, rats have altered hippocampal function, along the septo-temporal axis, prior to experiencing a traumatic event. In Experiment I, Res and Sus rats explored a novel box twice. Using a cellular imaging method for assessing plasticity-related immediate-early gene expression in large neuronal ensembles, Arc/Homer1a catFISH, we show that Sus rats have smaller vCA3 ensembles during the second exploration. This suppressed vCA3 activation in Sus rats was not due to a difference in exploratory behavior, or to a difference in Arc/Homer1a expression in the basolateral amygdala (BLA). BLA is a main source of inputs to vCA3, but both the ensemble size and overlap of BLA ensembles activated during the two explorations was similar to that of Res rats. Additionally, Sus rats had significant 'infidelity' in their dorsal hippocampal representations of the second event: a lower overlap, compared to Res rats, of Arc/Homer1a-expressing ensembles activated during the two explorations (the size of the ensembles were similar to those of Res rats). These differences were revealed only in conditions of relatively low stress, because they were not observed when Sus and Res rats experienced fear conditioning (Experiment II). Combined, the findings show that altered hippocampal function exists before experiencing emotional trauma in susceptible rats and suggest that this is a risk factor for PTSD.

  20. Intake of phthalate-tainted foods alters thyroid functions in Taiwanese children.

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    Ming-Tsang Wu

    Full Text Available BACKGROUND: On April-May, 2011, two Taiwan chemical companies were found to have intentionally added phthalates, Di-(2-ethylhexyl phthalate (DEHP and/or Di-isononyl phthalate, as a substitute of emulsifier to many foodstuffs. This study aimed to investigate whether exposure to these foods altered endocrine functions in children aged ≤10 years and, if so, whether those changes could be reversed by stopping exposure. METHODS: One Phthalates Clinic for Children was established in southern Taiwan between May 31 and June 17, 2011. All eligible children had their exposure information, blood and/or urine specimens collected. Endocrine functions were assessed in serum. The exposure groups were categorized into three (High, >500 ppm, Low, 1-500 ppm, and No, <1 ppm of DEHP. After six months, some children were followed up for the selected endocrine hormones. RESULTS: Sixty children were eligible in this study; all were Tanner stage 1 with no pubic hair. Compared to non-exposed group, both high and low exposure groups had significantly lower serum thyroid-stimulating hormone (TSH levels (P = 0.001 and 0.024. At six months follow-up, serum triiodothyronine (T3 levels was significantly changed (P = 0.034 in high exposure group (n = 13. For serum estradiol (E2, the detectable rate (≥8 pg/mL decreased from 76.9% (10/13 to 30.8% (4/13 (P = 0.070. CONCLUSIONS: This study shows that serum TSH levels can be altered when children were exposed to high concentrations of phthalate-tainted foodstuffs. Serum E2 and T3 may be partially recovered after stopping exposure.

  1. Nutritional and functional properties of whey proteins concentrate and isolate

    OpenAIRE

    Zoran Herceg; Anet Režek

    2006-01-01

    Whey protein fractions represent 18 - 20 % of total milk nitrogen content. Nutritional value in addition to diverse physico - chemical and functional properties make whey proteins highly suitable for application in foodstuffs. In the most cases, whey proteins are used because of their functional properties. Whey proteins possess favourable functional characteristics such as gelling, water binding, emulsification and foaming ability. Due to application of new process techniques (membrane fract...

  2. Functional Alterations of Ion Channels From Cardiac Fibroblasts in Heart Diseases

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    Gracious R. Ross

    2016-11-01

    Full Text Available In an aged population, cardiovascular disease is the leading cause of fatality and morbidity. Age-related fibrotic remodeling of the heart contributes to progressive myocardial dysfunction. Cardiac fibroblasts (CF, responsible for the maintenance of extracellular matrix and fibrosis process, play an important role in cardiac health and disease. CFs influence myocardial function by their chemical, electrical and mechanical interactions with cardiomyocytes through extracellular matrix deposition or secretion of cytokines and growth factors. These, in turn, are modulated by ion channels, macromolecular pores in the plasma membrane that allow selective ionic fluxes of major ions like K+, Ca2+, Na+ or Cl-, which affect membrane potential and cellular signal transduction. The importance of ion channels in modulating various functions of CFs, including proliferation, differentiation, secretion and apoptosis, is being recognized from recent studies of CFs from animal models and tissue from patients with various cardiac pathologies. Understanding the role of ion channels in CFs under physiological conditions and their alterations in age-related cardiac diseases may help facilitate development of novel therapeutic strategies to limit cardiac fibrosis and its adverse effect on myocardial function. This narrative review summarizes the knowledge gained thus far on ion channels in CFs and their relationship with cardiac diseases in human and experimental animal models.

  3. Fusion Protein Linkers: Property, Design and Functionality

    OpenAIRE

    Chen, Xiaoying; Zaro, Jennica; Shen, Wei-Chiang

    2012-01-01

    As an indispensable component of recombinant fusion proteins, linkers have shown increasing importance in the construction of stable, bioactive fusion proteins. This review covers the current knowledge of fusion protein linkers and summarizes examples for their design and application. The general properties of linkers derived from naturally-occurring multi-domain proteins can be considered as the foundation in linker design. Empirical linkers designed by researchers are generally classified i...

  4. Effect of storage on physical and functional properties of extracellular vesicles derived from neutrophilic granulocytes

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    Ákos M. Lőrincz

    2014-12-01

    Full Text Available Aim: To carry out a systematic study on the effect of different storage conditions on the number as well as the physical and functional properties of antibacterial extracellular vesicles (EVs derived from human neutrophilic granulocytes. Methods: Production of EVs with antibacterial properties was initiated by opsonized Zymosan A particles. The number of released fluorescent EVs was determined by flow cytometry following careful calibration. Physical properties and size of EVs were investigated by flow cytometry, dynamic light scattering and electron microscopy. Functional properties of EVs were tested by bacterial survival assay. Results: Storage at +20°C or +4°C resulted in a significant decrease of EV number and antibacterial effect after 1 day. Storage at −20°C did not influence the EV number up to 28 days, but induced a shift in EV size and almost complete loss of antibacterial function by 28 days. Storage at −80°C had no significant effect either on EV number or size and allowed partial preservation of the antibacterial function up to 28 days. Snap-freezing did not improve the results, whereas the widely used cryoprotectants induced EV lysis. Conclusion: Storage significantly alters both the physical and functional properties of EVs even if the number of EVs stays constant. If storage is needed, EVs should be kept at −80°C, preferably not longer than 7 days. For functional tests, freshly prepared EVs are recommended.

  5. Soil bacterial community and functional shifts in response to altered snowpack in moist acidic tundra of northern Alaska

    Science.gov (United States)

    Ricketts, Michael P.; Poretsky, Rachel S.; Welker, Jeffrey M.; Gonzalez-Meler, Miquel A.

    2016-09-01

    Soil microbial communities play a central role in the cycling of carbon (C) in Arctic tundra ecosystems, which contain a large portion of the global C pool. Climate change predictions for Arctic regions include increased temperature and precipitation (i.e. more snow), resulting in increased winter soil insulation, increased soil temperature and moisture, and shifting plant community composition. We utilized an 18-year snow fence study site designed to examine the effects of increased winter precipitation on Arctic tundra soil bacterial communities within the context of expected ecosystem response to climate change. Soil was collected from three pre-established treatment zones representing varying degrees of snow accumulation, where deep snow ˜ 100 % and intermediate snow ˜ 50 % increased snowpack relative to the control, and low snow ˜ 25 % decreased snowpack relative to the control. Soil physical properties (temperature, moisture, active layer thaw depth) were measured, and samples were analysed for C concentration, nitrogen (N) concentration, and pH. Soil microbial community DNA was extracted and the 16S rRNA gene was sequenced to reveal phylogenetic community differences between samples and determine how soil bacterial communities might respond (structurally and functionally) to changes in winter precipitation and soil chemistry. We analysed relative abundance changes of the six most abundant phyla (ranging from 82 to 96 % of total detected phyla per sample) and found four (Acidobacteria, Actinobacteria, Verrucomicrobia, and Chloroflexi) responded to deepened snow. All six phyla correlated with at least one of the soil chemical properties (% C, % N, C : N, pH); however, a single predictor was not identified, suggesting that each bacterial phylum responds differently to soil characteristics. Overall, bacterial community structure (beta diversity) was found to be associated with snow accumulation treatment and all soil chemical properties. Bacterial

  6. Functional neuroimaging during altered states of consciousness: how and what do we measure?

    Science.gov (United States)

    Hirsch, Joy

    2005-01-01

    The emergence of functional neuroimaging has extended the doctrine of functional specificity of the brain beyond the primary stages of perception, language, and motor systems to high-level cognitive, personality, and affective systems. This chapter applies functional magnetic resonance imaging to another high-level realm of cognition and neurology to characterize cortical function in patients with disorders of consciousness. At first pass, this objective appears paradoxical because conventional investigations of a cognitive process require experimental manipulation. For example, to map the location of language-sensitive cortex, a language-related task is performed according to a temporal sequence that alternates the task with rest (no-task) periods. Application of this approach to the study of consciousness would require that levels of consciousness be similarly varied, this is an unlikely technique. Alternatively, another strategy is presented here where the focus is on functional brain activity elicited during various passive stimulations of patients who are minimally conscious. Comparisons between patients with altered states of consciousness due to brain injury and healthy subjects may be employed to infer readiness and potential to sustain awareness. As if a behavioral microscope, fMRI enables a view of occluded neural processes to inform medical practitioners about the health of the neurocircuity-mediating cognitive processes. An underlying point of view is that assessment of recovery potential can be enhanced by neuroimaging techniques that reveal the status of residual systems specialized for essential cognitive and volitional tasks for each patient. Thus, development of imaging techniques that assess the functional status of individual unresponsive patients is a primary goal. The structural integrity of injured brains is often compromised depending on the specific traumatic event, and, therefore, images cannot be grouped across patients, as is the standard

  7. Limit properties of monotone matrix functions

    NARCIS (Netherlands)

    Behrndt, Jussi; Hassi, Seppo; de Snoo, Henk; Wietsma, Rudi

    2012-01-01

    The basic objects in this paper are monotonically nondecreasing n x n matrix functions D(center dot) defined on some open interval l = (a, b) of R and their limit values D(a) and D(b) at the endpoints a and b which are, in general, selfadjoint relations in C-n. Certain space decompositions induced b

  8. NLO properties of functionalized DNA thin films

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, Oksana [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France)], E-mail: okrupka@mail.ru; El-ghayoury, Abdelkrim [University d' Angers, UFR Sciences, Laboratoire CIMMA UMR CNRS 6200, 2 Bd. Lavoisier, 49045 (France); Rau, Ileana; Sahraoui, Bouchta [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France); Grote, James G. [Air Force Research Laboratory Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, 3005 Hobson Way, Dayton, OH 45433-7707 (United States); Kajzar, Francois [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France)

    2008-10-31

    In this paper we investigate the third-order nonlinear optical properties of spin deposited thin films of DNA-based complexes using the optical third harmonic generation (THG) technique at a fundamental wavelength of 1064 nm. We found that the third-order susceptibility, {chi}{sup (3)}(- 3{omega};{omega},{omega},{omega}), of DNA-based films was about one order of magnitude larger than that of our reference, a pure silica slab. In thin films doped with 5% of the chromophore disperse red 1 (DR1), a two order of magnitude larger value of {chi}{sup (3)}(- 3{omega};{omega},{omega},{omega}) was observed.

  9. THE ANALYTICAL PROPERTIES FOR HOMOGENEOUS RANDOM TRANSITION FUNCTIONS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The concepts of Markov process in random environment and homogeneous random transition functions are introduced. The necessary and sufficient conditions for homogeneous random transition function are given. The main results in this article are the analytical properties, such as continuity, differentiability, random Kolmogorov backward equation and random Kolmogorov forward equation of homogeneous random transition functions.

  10. Functionalized hexagonal boron nitride nanomaterials: emerging properties and applications.

    Science.gov (United States)

    Weng, Qunhong; Wang, Xuebin; Wang, Xi; Bando, Yoshio; Golberg, Dmitri

    2016-07-11

    Functionalization is an important way to breed new properties and applications for a material. This review presents an overview of the progresses in functionalized hexagonal boron nitride (h-BN) nanomaterials. It begins with an introduction of h-BN structural features, physical and chemical properties, followed by an emphasis on the developments of BN functionalization strategies and its emerging properties/applications, and ends with the research perspectives. Different functionalization methods, including physical and chemical routes, are comprehensively described toward fabrication of various BN derivatives, hetero- and porous structures, etc. Novel properties of functionalized BN materials, such as high water solubility, excellent biocompatibility, tunable surface affinities, good processibility, adjustable band gaps, etc., have guaranteed wide applications in biomedical, electronic, composite, environmental and "green" energy-related fields.

  11. Early lingual frenectomy assisted by CO2 laser helps prevention and treatment of functional alterations caused by ankyloglossia.

    Science.gov (United States)

    Fiorotti, Renata C; Bertolini, Milene M; Nicola, Jorge H; Nicola, Ester M D

    2004-11-01

    Incorrectly produced speech sounds, the presence of dentofacial alterations and acquired functional adaptations may be due to a short and inadequate lingual frenum. When frenectomy is indicated, it should be performed as early as possible to prevent functional alterations. This study presents a literature review on correct lingual positioning in relation to orthodontic and phonetic function as well as an assessment of 15 patients who underwent frenectomy utilizing the carbon dioxide laser. The results demonstrated that this technique is safe, effective and perfect for use in young children and can be performed in an outpatient unit.

  12. Fused aromatic thienopyrazines: structure, properties and function

    KAUST Repository

    Mondal, Rajib

    2010-01-01

    Recent development of a fused aromatic thieno[3.4-b]pyrazine system and their application in optoelectronic devices are reviewed. Introduction of a fused aromatic unit followed by side chain engineering, dramatically enhanced the charge carrier mobility in thin film transistor devices and mobilities up to 0.2 cm2/Vs were achieved. The optoelectronic properties of these fused aromatic thienopyrazine polymers (Eg = 1.3 to 1.6 eV, HOMO = -4.9 to -5.2 V) were tuned by introduction of various fused aromatic rings within thienopyrazine. By balancing the fundamental properties of these polymers, both high charge carrier mobilities and moderate PCEs in solar cells were achieved. Further, effects of copolymerizing units are discussed. Low band gap semiconducting polymer (Eg ∼ 1 eV) with high field effect mobility (0.044 cm2/Vs) was obtained using cyclopentadithiophene as copolymerizing unit. Finally, a molecular design approach to enhance the absorption coefficients is discussed, which resulted in improved power conversion efficiency in bulk heterojunction solar cells. © 2010 The Royal Society of Chemistry.

  13. Altered small-world properties of gray matter networks in breast cancer

    Directory of Open Access Journals (Sweden)

    Hosseini S M

    2012-05-01

    Full Text Available Abstract Background Breast cancer survivors, particularly those treated with chemotherapy, are at significantly increased risk for long-term cognitive and neurobiologic impairments. These deficits tend to involve skills that are subserved by distributed brain networks. Additionally, neuroimaging studies have shown a diffuse pattern of brain structure changes in chemotherapy-treated breast cancer survivors that might impact large-scale brain networks. Methods We therefore applied graph theoretical analysis to compare the gray matter structural networks of female breast cancer survivors with a history of chemotherapy treatment and healthy age and education matched female controls. Results Results revealed reduced clustering coefficient and small-world index in the brain network of the breast cancer patients across a range of network densities. In addition, the network of the breast cancer group had less highly interactive nodes and reduced degree/centrality in the frontotemporal regions compared to controls, which may help explain the common impairments of memory and executive functioning among these patients. Conclusions These results suggest that breast cancer and chemotherapy may decrease regional connectivity as well as global network organization and integration, reducing efficiency of the network. To our knowledge, this is the first report of altered large-scale brain networks associated with breast cancer and chemotherapy.

  14. Magnesium regulates neural stem cell proliferation in the mouse hippocampus by altering mitochondrial function.

    Science.gov (United States)

    Jia, Shanshan; Mou, Chengzhi; Ma, Yihe; Han, Ruijie; Li, Xue

    2016-04-01

    In the adult brain, neural stem cells from the subgranular zone (SGZ) of the hippocampus and the subventricular zone (SVZ) of the cortex progress through the following five developmental stages: radial glia-like cells, neural progenitor cells, neuroblasts, immature neurons, and mature neurons. These developmental stages are linked to both neuronal microenvironments and energy metabolism. Neurogenesis is restricted and has been demonstrated to arise from tissue microenvironments. We determined that magnesium, a key nutrient in cellular energy metabolism, affects neural stem cell (NSC) proliferation in cells derived from the embryonic hippocampus by influencing mitochondrial function. Densities of proliferating cells and NSCs both showed their highest values at 0.8 mM [Mg(2+) ]o , whereas lower proliferation rates were observed at 0.4 and 1.4 mM [Mg(2+) ]o . The numbers and sizes of the neurospheres reached the maximum at 0.8 mM [Mg(2+) ]o and were weaker under both low (0.4 mM) and high (1.4 mM) concentrations of magnesium. In vitro experimental evidence demonstrates that extracellular magnesium regulates the number of cultured hippocampal NSCs, affecting both magnesium homeostasis and mitochondrial function. Our findings indicate that the effect of [Mg(2+) ]o on NSC proliferation may lie downstream of alterations in mitochondrial function because mitochondrial membrane potential was highest in the NSCs in the moderate [Mg(2+) ]o (0.8 mM) group and lower in both the low (0.4 mM) and high (1.4 mM) [Mg(2+) ]o groups. Overall, these findings demonstrate a new function for magnesium in the brain in the regulation of hippocampal neural stem cells: affecting their cellular energy metabolism.

  15. Scanning MscL Channels with Targeted Post-Translational Modifications for Functional Alterations.

    Directory of Open Access Journals (Sweden)

    Irene Iscla

    Full Text Available Mechanosensitive channels are present in all living organisms and are thought to underlie the senses of touch and hearing as well as various important physiological functions like osmoregulation and vasoregulation. The mechanosensitive channel of large conductance (MscL from Escherichia coli was the first protein shown to encode mechanosensitive channel activity and serves as a paradigm for how a channel senses and responds to mechanical stimuli. MscL plays a role in osmoprotection in E. coli, acting as an emergency release valve that is activated by membrane tension due to cell swelling after an osmotic down-shock. Using an osmotically fragile strain in an osmotic down-shock assay, channel functionality can be directly determined in vivo. In addition, using thiol reagents and expressed MscL proteins with a single cysteine substitution, we have shown that targeted post-translational modifications can be performed, and that any alterations that lead to dysfunctional proteins can be identified by this in vivo assay. Here, we present the results of such a scan performed on 113 MscL cysteine mutants using five different sulfhydryl-reacting probes to confer different charges or hydrophobicity to each site. We assessed which of these targeted modifications affected channel function and the top candidates were further studied using patch clamp to directly determine how channel activity was affected. This comprehensive screen has identified many residues that are critical for channel function as well as highlighted MscL domains and residues that undergo the most drastic environmental changes upon gating.

  16. Acid weathering of basalt and basaltic glass: 2. Effects of microscopic alteration textures on spectral properties

    Science.gov (United States)

    Smith, Rebecca J.; Horgan, Briony H. N.; Mann, Paul; Cloutis, Edward A.; Christensen, Philip R.

    2017-01-01

    Acid alteration has long been proposed for the Martian surface, and so it is important to understand how the resulting alteration textures affect surface spectra. Two basaltic materials of varying crystallinity were altered in two different H2SO4 solutions (pH 1 and pH 3) for 220 days. The unaltered and altered samples were studied in the visible and near infrared (VNIR) and thermal infrared (TIR), and select samples were chosen for scanning electron microscopy analysis. Materials altered in pH 3 solutions showed little to no physical alteration, and their spectral signatures changed very little. In contrast, all materials altered in pH 1 acid displayed silica-rich alteration textures, and the morphology differed based on starting material crystallinity. The more crystalline material displayed extensive alteration reaching into the sample interiors and had weaker silica spectral features. The glass sample developed alteration layers tens of microns thick, exhibiting amorphous silica-rich spectral features that completely obscured the substrate. Thus, the strong absorption coefficient of silica effectively decreases the penetration depth of TIR spectral measurements, causing silica abundances to be grossly overestimated in remote sensing data. Additionally, glass samples with silica layers exhibited distinct concave up blue spectral slopes in the VNIR. Spectra from the northern lowland plains of Mars are modeled with high abundances of amorphous silica and exhibit concave up blue spectral slopes and are thus consistent with acid altered basaltic glass. Therefore, we conclude that large regions of the Martian surface may have formed through the interaction of basaltic glass with strongly acidic fluids.

  17. Age-related changes in rat myocardium involve altered capacities of glycosaminoglycans to potentiate growth factor functions and heparan sulfate-altered sulfation.

    Science.gov (United States)

    Huynh, Minh Bao; Morin, Christophe; Carpentier, Gilles; Garcia-Filipe, Stephanie; Talhas-Perret, Sofia; Barbier-Chassefière, Véronique; van Kuppevelt, Toin H; Martelly, Isabelle; Albanese, Patricia; Papy-Garcia, Dulce

    2012-03-30

    Glycosaminoglycans (GAGs) are essential components of the extracellular matrix, the natural environment from which cell behavior is regulated by a number or tissue homeostasis guarantors including growth factors. Because most heparin-binding growth factor activities are regulated by GAGs, structural and functional alterations of these polysaccharides may consequently affect the integrity of tissues during critical physiological and pathological processes. Here, we investigated whether the aging process can induce changes in the myocardial GAG composition in rats and whether these changes can affect the activities of particular heparin-binding growth factors known to sustain cardiac tissue integrity. Our results showed an age-dependent increase of GAG levels in the left ventricle. Biochemical and immunohistological studies pointed out heparan sulfates (HS) as the GAG species that increased with age. ELISA-based competition assays showed altered capacities of the aged myocardial GAGs to bind FGF-1, FGF-2, and VEGF but not HB EGF. Mitogenic assays in cultured cells showed an age-dependent decrease of the elderly GAG capacities to potentiate FGF-2 whereas the potentiating effect on VEGF(165) was increased, as confirmed by augmented angiogenic cell proliferation in Matrigel plugs. Moreover, HS disaccharide analysis showed considerably altered 6-O-sulfation with modest changes in N- and 2-O-sulfations. Together, these findings suggest a physiological significance of HS structural and functional alterations during aging. This can be associated with an age-dependent decline of the extracellular matrix capacity to efficiently modulate not only the activity of resident or therapeutic growth factors but also the homing of resident or therapeutic cells.

  18. Clinical, cognitive, and functional connectivity correlations of resting-state intrinsic brain activity alterations in unmedicated depression

    OpenAIRE

    Tadayonnejad, Reza; Yang, Shaolin; Kumar, Anand; Ajilore, Olusola

    2014-01-01

    The pervasive and persistent nature of depressive symptoms has made resting-state functional magnetic resonance imaging (rs-fMRI) an appropriate approach for understanding the underlying mechanisms of major depressive disorder. The majority of rs-fMRI research has focused on depression-related alterations in the interregional coordination of brain baseline low frequency oscillations (LFOs). However, alteration of the regional amplitude of LFOs in depression, particularly its clinical, cogniti...

  19. Seismic properties and effects of hydrothermal alteration on Volcanogenic Massive Sulfide (VMS) deposits at the Lalor Lake in Manitoba, Canada

    Science.gov (United States)

    Miah, Khalid H.; Bellefleur, Gilles; Schetselaar, Ernst; Potter, David K.

    2015-12-01

    Borehole sonic and density logs are essential for mineral exploration at depth, but its limited availability to link rock properties of different ore forming geologic structure is a hindrance to seismic data interpretations. In situ density and velocity logs provide first order control on the reflectivity of various lithologic units. We analyzed borehole logs from 12 drill holes over and around the Lalor VMS deposits geographically located in the northern Manitoba, Canada, in an attempt to characterize lithologic units based on its seismic properties. The Lalor Lake deposit is part of the Paleoproterozoic Flin Flon Belt, and associated with an extensive hydrothermal alteration system. Volcanogenic Massive Sulfide (VMS) zones are distributed in several ore lenses with relatively shallower facies comprise solid to solid sulfides, tend to be disseminated or Stringer sulfides, while deeper lenses are gold and silver enriched and occurred in the highly altered footwall region. Our analysis suggests that massive sulfide and diorite have higher acoustic impedance than other rock units, and can produce useful reflection signatures in seismic data. Bivariate distributions of P-wave velocity, density, acoustic impedance and Poisson's ratio in end-member mineral cones were used for qualitative assessment of the extent of alteration of various lithologic units. It can be inferred that hydrothermal alteration has considerably increased P-wave velocity and density of altered argillite and felsic volcanic rocks in comparison to their corresponding unaltered facies. Amphibole, garnet, kyanite, pyrite, sphalerite and staurolite are the dominant end-member alteration minerals affecting seismic rock properties at the VMS site.

  20. A default mode of brain function in altered states of consciousness.

    Science.gov (United States)

    Guldenmund, P; Vanhaudenhuyse, A; Boly, M; Laureys, S; Soddu, A

    2012-01-01

    Using modern brain imaging techniques, new discoveries are being made concerning the spontaneous activity of the brain when it is devoid of attention-demanding tasks. Spatially separated patches of neuronal assemblies have been found to show synchronized oscillatory activity behavior and are said to be functionally connected. One of the most robust of these is the default mode network, which is associated with intrinsic processes like mind wandering and self-projection. Furthermore, activity in this network is anticorrelated with activity in a network that is linked to attention to external stimuli. The integrity of both networks is disturbed in altered states of consciousness, like sleep, general anesthesia and hypnosis. In coma and related disorders of consciousness, encompassing the vegetative state (unresponsive wakefulness syndrome) and minimally conscious state, default mode network integrity correlates with the level of remaining consciousness, offering the possibility of using this information for diagnostic and prognostic purposes. Functional brain imaging is currently being validated as a valuable addition to the standardized behavioral assessments that are already in use.

  1. Leptin alters the structural and functional characteristics of adipose tissue before birth.

    Science.gov (United States)

    Yuen, B S J; Owens, P C; Muhlhausler, B S; Roberts, C T; Symonds, M E; Keisler, D H; McFarlane, J R; Kauter, K G; Evens, Y; McMillen, I C

    2003-06-01

    This study aimed to determine for the first time whether leptin can act to alter the structural and functional characteristics of adipose tissue before birth. Leptin (0.48 mg/kg/day) or saline was infused intravenously into fetal sheep for 4 days from either 136 or 137 days of gestation (term=147+/-3 days). Circulating leptin concentrations were increased approximately four- to fivefold by leptin infusion. Leptin infusion resulted in a significant increase in the proportion of smaller lipid locules present within fetal perirenal adipose tissue (PAT), and this was associated with a significant increase in the proportion of multilocular tissue and a significant decrease in the proportion and relative mass of unilocular tissue in fetal PAT. The relative abundance of leptin mRNA in fetal PAT was significantly lower in the leptin-infused group, and there was a positive correlation between the relative abundance of leptin mRNA and the proportion of unilocular adipose tissue in fetal PAT. The amount of uncoupling protein 1 tended to be higher (P=0.06) in leptin-infused compared with saline-infused fetuses. This is the first demonstration that leptin can act to regulate the lipid storage characteristics, leptin synthetic capacity, and potential thermogenic functions of fat before birth.

  2. Mindfulness meditation training alters stress-related amygdala resting state functional connectivity: a randomized controlled trial.

    Science.gov (United States)

    Taren, Adrienne A; Gianaros, Peter J; Greco, Carol M; Lindsay, Emily K; Fairgrieve, April; Brown, Kirk Warren; Rosen, Rhonda K; Ferris, Jennifer L; Julson, Erica; Marsland, Anna L; Bursley, James K; Ramsburg, Jared; Creswell, J David

    2015-12-01

    Recent studies indicate that mindfulness meditation training interventions reduce stress and improve stress-related health outcomes, but the neural pathways for these effects are unknown. The present research evaluates whether mindfulness meditation training alters resting state functional connectivity (rsFC) of the amygdala, a region known to coordinate stress processing and physiological stress responses. We show in an initial discovery study that higher perceived stress over the past month is associated with greater bilateral amygdala-subgenual anterior cingulate cortex (sgACC) rsFC in a sample of community adults (n = 130). A follow-up, single-blind randomized controlled trial shows that a 3-day intensive mindfulness meditation training intervention (relative to a well-matched 3-day relaxation training intervention without a mindfulness component) reduced right amygdala-sgACC rsFC in a sample of stressed unemployed community adults (n = 35). Although stress may increase amygdala-sgACC rsFC, brief training in mindfulness meditation could reverse these effects. This work provides an initial indication that mindfulness meditation training promotes functional neuroplastic changes, suggesting an amygdala-sgACC pathway for stress reduction effects.

  3. Functional insights into modulation of BKCa channel activity to alter myometrial contractility

    Directory of Open Access Journals (Sweden)

    Ramón A Lorca

    2014-07-01

    Full Text Available The large-conductance voltage- and Ca2+-activated K+ channel (BKCa is an important regulator of membrane excitability in a wide variety of cells and tissues. In myometrial smooth muscle, activation of BKCa plays essential roles in buffering contractility to maintain uterine quiescence during pregnancy and in the transition to a more contractile state at the onset of labor. Multiple mechanisms of modulation have been described to alter BKCa channel activity, expression, and cellular localization. In the myometrium, BKCa is regulated by alternative splicing, protein targeting to the plasma membrane, compartmentation in membrane microdomains, and posttranslational modifications. In addition, interaction with auxiliary proteins (i.e., β1- and β2-subunits, association with G-protein coupled receptor signaling pathways, such as those activated by adrenergic and oxytocin receptors, and hormonal regulation provide further mechanisms of variable modulation of BKCa channel function in myometrial smooth muscle. Here, we provide an overview of these mechanisms of BKCa channel modulation and provide a context for them in relation to myometrial function.

  4. A deficiency of uPAR alters endothelial angiogenic function and cell morphology

    Directory of Open Access Journals (Sweden)

    Balsara Rashna D

    2011-05-01

    Full Text Available Abstract The angiogenic potential of a cell requires dynamic reorganization of the cytoskeletal architecture that involves the interaction of urokinase-type plasminogen activator receptor (uPAR with the extracellular matrix. This study focuses on the effect of uPAR deficiency (uPAR-/- on angiogenic function and associated cytoskeletal organization. Utilizing murine endothelial cells, it was observed that adhesion, migration, proliferation, and capillary tube formation were altered in uPAR-/- cells compared to wild-type (WT cells. On a vitronectin (Vn matrix, uPAR-/- cells acquired a "fried egg" morphology characterized by circular actin organization and lack of lamellipodia formation. The up-regulation of β1 integrin, FAK(P-Tyr925, and paxillin (P-Tyr118, and decreased Rac1 activation, suggested increased focal adhesions, but delayed focal adhesion turnover in uPAR-/- cells. This accounted for the enhanced adhesion, but attenuated migration, on Vn. VEGF-enriched Matrigel implants from uPAR-/- mice demonstrated a lack of mature vessel formation compared to WT mice. Collectively, these results indicate that a uPAR deficiency leads to decreased angiogenic functions of endothelial cells.

  5. Altered resting-state amygdala functional connectivity in men with posttraumatic stress disorder

    Science.gov (United States)

    Sripada, Rebecca K.; King, Anthony P.; Garfinkel, Sarah N.; Wang, Xin; Sripada, Chandra S.; Welsh, Robert C.; Liberzon, Israel

    2012-01-01

    Background Converging neuroimaging research suggests altered emotion neurocircuitry in individuals with posttraumatic stress disorder (PTSD). Emotion activation studies in these individuals have shown hyperactivation in emotion-related regions, including the amygdala and insula, and hypoactivation in emotion-regulation regions, including the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC). However, few studies have examined patterns of connectivity at rest in individuals with PTSD, a potentially powerful method for illuminating brain network structure. Methods Using the amygdala as a seed region, we measured resting-state brain connectivity using 3 T functional magnetic resonance imaging in returning male veterans with PTSD and combat controls without PTSD. Results Fifteen veterans with PTSD and 14 combat controls enrolled in our study. Compared with controls, veterans with PTSD showed greater positive connectivity between the amygdala and insula, reduced positive connectivity between the amygdala and hippocampus, and reduced anticorrelation between the amygdala and dorsal ACC and rostral ACC. Limitations Only male veterans with combat exposure were tested, thus our findings cannot be generalized to women or to individuals with non–combat related PTSD. Conclusion These results demonstrate that studies of functional connectivity during resting state can discern aberrant patterns of coupling within emotion circuits and suggest a possible brain basis for emotion-processing and emotion-regulation deficits in individuals with PTSD. PMID:22313617

  6. Association of altered cardiac autonomic function with psychopathology and metabolic profiles in schizophrenia.

    Science.gov (United States)

    Chung, Ming-Shun; Yang, Albert C; Lin, Yu-Chung; Lin, Chieh-Nan; Chang, Fang-Rong; Shen, Shu-hua; Ouyang, Wen-Chen; Loh, El-Wui; Chiu, Hsien-Jane

    2013-12-30

    Schizophrenia has been associated with autonomic dysregulation and increased cardiovascular co-morbidity. We hypothesised that autonomic dysregulation in patients with schizophrenia is associated with psychopathology and metabolic profiles. In this study, we aimed to evaluate psychopathology, comprehensive metabolic profiles and cardiac autonomic function using heart-rate variability (HRV) analysis in patients with schizophrenia. A total of 94 patients with schizophrenia and 51 healthy controls were recruited. Each patient underwent a physical examination, laboratory tests and rating scale evaluation, and all subjects underwent a 1-h electrocardiogram monitoring. Analysis of variance was used to compare demographic and HRV variables between control and patient groups. We applied multiple regression analysis with backward selection to examine the association between HRV indices and demographic, metabolic and psychopathology profiles. A decreased HRV was found in patient groups, compared to controls. Reduced vagal-related and complexity domain of HRV indices in patient groups were correlated with increased body mass indices, diastolic pressure, triglycerides, high- and low-density lipoprotein and severity of psychosis mainly in the negative symptom domain. This study provides evidence that altered autonomic function is associated with both psychopathology and metabolic profiles in patients with schizophrenia. These findings may warrant future research in using HRV as objective markers to monitor cardiovascular health and the severity of psychosis in patients with schizophrenia.

  7. Diet-induced obesity alters dendritic cell function in the presence and absence of tumor growth.

    Science.gov (United States)

    James, Britnie R; Tomanek-Chalkley, Ann; Askeland, Eric J; Kucaba, Tamara; Griffith, Thomas S; Norian, Lyse A

    2012-08-01

    Obesity is a mounting health concern in the United States and is associated with an increased risk for developing several cancers, including renal cell carcinoma (RCC). Despite this, little is known regarding the impact of obesity on antitumor immunity. Because dendritic cells (DC) are critical regulators of antitumor immunity, we examined the combined effects of obesity and tumor outgrowth on DC function. Using a diet-induced obesity (DIO) model, DC function was evaluated in mice bearing orthotopic RCC and in tumor-free controls. Tumor-free DIO mice had profoundly altered serum cytokine and chemokine profiles, with upregulation of 15 proteins, including IL-1α, IL-17, and LIF. Tumor-free DIO mice had elevated percentages of conventional splenic DC that were impaired in their ability to stimulate naive T cell expansion, although they were phenotypically similar to normal weight (NW) controls. In DIO mice, intrarenal RCC tumor challenge in the absence of therapy led to increased local infiltration by T cell-suppressive DC and accelerated early tumor outgrowth. Following administration of a DC-dependent immunotherapy, established RCC tumors regressed in normal weight mice. The same immunotherapy was ineffective in DIO mice and was characterized by an accumulation of regulatory DC in tumor-bearing kidneys, decreased local infiltration by IFN-γ-producing CD8 T cells, and progressive tumor outgrowth. Our results suggest that the presence of obesity as a comorbidity can impair the efficacy of DC-dependent antitumor immunotherapies.

  8. Methamidophos alters sperm function and DNA at different stages of spermatogenesis in mice

    Energy Technology Data Exchange (ETDEWEB)

    Urióstegui-Acosta, Mayrut; Hernández-Ochoa, Isabel [Departamento de Toxicología, CINVESTAV-IPN, D.F. (Mexico); Sánchez-Gutiérrez, Manuel [Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Hidalgo (Mexico); Piña-Guzmán, Belem [Instituto Politécnico Nacional-UPIBI, D.F. (Mexico); Rafael-Vázquez, Leticia; Solís-Heredia, M.J.; Martínez-Aguilar, Gerardo [Departamento de Toxicología, CINVESTAV-IPN, D.F. (Mexico); Quintanilla-Vega, Betzabet, E-mail: mquintan@cinvestav.mx [Departamento de Toxicología, CINVESTAV-IPN, D.F. (Mexico)

    2014-09-15

    Methamidophos (MET) is a highly toxic organophosphate (OP) pesticide that is widely used in developing countries. MET has male reproductive effects, including decreased fertility. We evaluated MET effects on sperm quality, fertilization and DNA integrity, exploring the sensitivity of different stages of spermatogenesis. Adult male mice received MET (3.75 or 5 mg/kg-bw/ip/day/4 days) and were euthanized 1, 28 or 45 days post-treatment (dpt) to evaluate MET's effects on epididymal maturation, meiosis or mitosis, respectively. Spermatozoa were obtained from the cauda epididymis–vas deferens and were evaluated for sperm quality, acrosome reaction (AR; Coomassie staining), mitochondrial membrane potential (by JC-1), DNA damage (comet assay), oxidative damage (malondialdehyde (MDA) production), in vitro fertilization and protein phosphorylation (immunodetection), and erythrocyte acetylcholinesterase (AChE) activity. At 1-dpt, MET inhibited AChE (43–57%) and increased abnormal cells (6%). While at 28- and 45-dpt, sperm motility and viability were significantly reduced with an increasing MET dose, and abnormal morphology increased at 5 mg/kg/day/4 days. MDA and mitochondrial activity were not affected at any dose or time. DNA damage (OTM and %DNA) was observed at 5 mg/kg/day/4 days in a time-dependent manner, whereas both parameters were altered in cells from mice exposed to 3.75 mg/kg/day/4 days only at 28-dpt. Depending on the time of collection, initial-, spontaneous- and induced-AR were altered at 5 mg/kg/day/4 days, and the fertilization capacity also decreased. Sperm phosphorylation (at serine and tyrosine residues) was observed at all time points. Data suggest that meiosis and mitosis are the more sensitive stages of spermatogenesis for MET reproductive toxicity compared to epididymal maturation. - Highlights: • Methamidophos alters sperm cell function at different stages of spermatogenesis. • Testicular stages of spermatogenesis are more sensitive to

  9. Altered neuronal excitability underlies impaired hippocampal function in an animal model of psychosis

    Directory of Open Access Journals (Sweden)

    Thomas eGrüter

    2015-05-01

    Full Text Available Psychosis is accompanied by severe attentional deficits, and impairments in associational-memory processing and sensory information processing that are ascribed to dysfunctions in prefrontal and hippocampal function. Disruptions of glutamatergic signalling may underlie these alterations: Antagonism of the N-methyl-D-aspartate receptor (NMDAR results in similar molecular, cellular, cognitive and behavioural changes in rodents and/or humans as those that occur in psychosis, raising the question as to whether changes in glutamatergic transmission may be intrinsic to the pathophysiology of the disease. In an animal model of psychosis that comprises treatment with the irreversible NMDAR-antagonist, MK801, we explored the cellular mechanisms that may underlie hippocampal dysfunction in psychosis. MK801-treatment resulted in a profound loss of hippocampal LTP that was evident 4 weeks after treatment. Whereas neuronal expression of the immediate early gene, Arc, was enhanced in the hippocampus by spatial learning in controls, MK801-treated animals failed to show activity-dependent increases in Arc expression. By contrast, a significant increase in basal Arc expression in the absence of learning was evident compared to controls. Paired-pulse facilitation was increased at the 40 ms interval indicating that NMDAR and/or fast GABAergic-mediated neurotransmission was disrupted. In line with this, MK801-treatment resulted in a significant decrease in GABA(A, and increase in GABA(B-receptor-expression in PFC, along with a significant increase of GABA(B- and NMDAR-GluN2B expression in the dentate gyrus. NMDAR-GluN1 or GluN2A subunit expression was unchanged. These data suggest that in psychosis, deficits in hippocampus-dependent memory may be caused by a loss of hippocampal LTP that arises through enhanced hippocampal neuronal excitability, altered GluN2B and GABA receptor expression and an uncoupling of the hippocampus-prefrontal cortex circuitry.

  10. Aged mice have increased inflammatory monocyte concentration and altered expression of cell-surface functional receptors

    Indian Academy of Sciences (India)

    Kelley Strohacker; Whitney L Breslin; Katie C Carpenter; Brian K McFarlin

    2012-03-01

    The expression of monocyte cell-surface receptors represents one index of immune dysfunction, which is common with aging. Although mouse models of aging are prevalent, monocyte subset assessment is rare. Our purpose was to compare cell receptor expression on classic (CD115+/Gr-1high) and non-classic (CD115+/Gr-1low) monocytes from 80- or 20-week-old CD-1 mice. Three-colour flow cytometry was used to determine the concentration of monocyte subsets and their respective cell-surface expression of TLR2, TLR4, CD80, CD86, MHC II and CD54. These receptors were selected because they have been previously associated with altered monocyte function. Data were analysed with independent -tests; significance was set at < 0.05. Old mice had a greater concentration of both classic (258%, =0.003) and non-classic (70%, =0.026) monocytes. The classic : non-classic monocyte ratio doubled in old as compared with that in young mice (=0.006), indicating a pro-inflammatory shift. TLR4 ($\\downarrow$27%, =0.001) and CD80 ($\\downarrow$37%, =0.004) were decreased on classic monocytes from old as compared with those from young mice. TLR2 ($\\uparrow$24%, =0.002) and MHCII ($\\downarrow$21%, =0.026) were altered on non-classic monocytes from old as compared with those from young mice. The increased classic : non-classic monocyte ratio combined with changes in the cell-surface receptor expression on both monocyte subsets is indicative of immune dysfunction, which may increase age-associated disease risk.

  11. Altered neuronal excitability underlies impaired hippocampal function in an animal model of psychosis

    Science.gov (United States)

    Grüter, Thomas; Wiescholleck, Valentina; Dubovyk, Valentyna; Aliane, Verena; Manahan-Vaughan, Denise

    2015-01-01

    Psychosis is accompanied by severe attentional deficits, and impairments in associational-memory processing and sensory information processing that are ascribed to dysfunctions in prefrontal and hippocampal function. Disruptions of glutamatergic signaling may underlie these alterations: Antagonism of the N-methyl-D-aspartate receptor (NMDAR) results in similar molecular, cellular, cognitive and behavioral changes in rodents and/or humans as those that occur in psychosis, raising the question as to whether changes in glutamatergic transmission may be intrinsic to the pathophysiology of the disease. In an animal model of psychosis that comprises treatment with the irreversible NMDAR-antagonist, MK801, we explored the cellular mechanisms that may underlie hippocampal dysfunction in psychosis. MK801-treatment resulted in a profound loss of hippocampal LTP that was evident 4 weeks after treatment. Whereas neuronal expression of the immediate early gene, Arc, was enhanced in the hippocampus by spatial learning in controls, MK801-treated animals failed to show activity-dependent increases in Arc expression. By contrast, a significant increase in basal Arc expression in the absence of learning was evident compared to controls. Paired-pulse (PP) facilitation was increased at the 40 ms interval indicating that NMDAR and/or fast GABAergic-mediated neurotransmission was disrupted. In line with this, MK801-treatment resulted in a significant decrease in GABA(A), and increase in GABA(B)-receptor-expression in PFC, along with a significant increase of GABA(B)- and NMDAR-GluN2B expression in the dentate gyrus. NMDAR-GluN1 or GluN2A subunit expression was unchanged. These data suggest that in psychosis, deficits in hippocampus-dependent memory may be caused by a loss of hippocampal LTP that arises through enhanced hippocampal neuronal excitability, altered GluN2B and GABA receptor expression and an uncoupling of the hippocampus-prefrontal cortex circuitry. PMID:26042007

  12. Mechano-growth factor induces migration of rat mesenchymal stem cells by altering its mechanical properties and activating ERK pathway

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jiamin; Wu, Kewen; Lin, Feng; Luo, Qing; Yang, Li; Shi, Yisong [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Song, Guanbin, E-mail: song@cqu.edu.cn [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Sung, Kuo-Li Paul [Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044 (China); Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093-0412 (United States)

    2013-11-08

    Highlights: •MGF induced the migration of rat MSC in a concentration-dependent manner. •MGF enhanced the mechanical properties of rMSC in inducing its migration. •MGF activated the ERK 1/2 signaling pathway of rMSC in inducing its migration. •rMSC mechanics may synergy with ERK 1/2 pathway in MGF-induced rMSC migration. -- Abstract: Mechano-growth factor (MGF) generated by cells in response to mechanical stimulation has been identified as a mechano effector molecule, playing a key role in regulating mesenchymal stem cell (MSC) function, including proliferation and migration. However, the mechanism(s) underlying how MGF-induced MSC migration occurs is still unclear. In the present study, MGF motivated migration of rat MSCs (rMSCs) in a concentration-dependent manner and optimal concentration of MGF at 50 ng/mL (defined as MGF treatment in this paper) was demonstrated. Notably, enhancement of mechanical properties that is pertinent to cell migration, such as cell traction force and cell stiffness were found to respond to MGF treatment. Furthermore, MGF increased phosphorylation of extracellular signal-regulated kinase (ERK), ERK inhibitor (i.e., PD98059) suppressed ERK phosphorylation, and abolished MGF-induced rMSC migration were found, demonstrating that ERK is involved molecule for MGF-induced rMSC migration. These in vitro evidences of MGF-induced rMSC migration and its direct link to altering rMSC mechanics and activating the ERK pathway, uncover the underlying biomechanical and biological mechanisms of MGF-induced rMSC migration, which may help find MGF-based application of MSC in clinical therapeutics.

  13. ALTERATIONS OF PROPERTIES OF RED BLOOD CELLS MEMBRANES PROTEINS OF DIFFERENT AGE AND SEX VOLUNTEERS.

    Science.gov (United States)

    Pruidze, N; Khetsuriani, R; Sujashvili, R; Ioramashvili, I; Arabuli, M; Sanikidze, T

    2015-01-01

    disorders of protein-protein interaction mechanisms, their ubiquitinylation or oligomerisation and formation of high molecular weight complexes of inactivated proteins in aged RBCs. These processes play important role in regulation of the RBCs shape and stability. Identified sex- and age-related alterations in RBCs membranes proteins affect the rheological properties of blood and can be considered as the etiologic and pathogenic markers of various diseases.

  14. Quinoa (Chenopodium quinoa Willd.): composition, chemistry, nutritional, and functional properties.

    Science.gov (United States)

    Abugoch James, Lilian E

    2009-01-01

    Quinoa (Chenopodium quinoa Willd.), which is considered a pseudocereal or pseudograin, has been recognized as a complete food due to its protein quality. It has remarkable nutritional properties; not only from its protein content (15%) but also from its great amino acid balance. It is an important source of minerals and vitamins, and has also been found to contain compounds like polyphenols, phytosterols, and flavonoids with possible nutraceutical benefits. It has some functional (technological) properties like solubility, water-holding capacity (WHC), gelation, emulsifying, and foaming that allow diversified uses. Besides, it has been considered an oil crop, with an interesting proportion of omega-6 and a notable vitamin E content. Quinoa starch has physicochemical properties (such as viscosity, freeze stability) which give it functional properties with novel uses. Quinoa has a high nutritional value and has recently been used as a novel functional food because of all these properties; it is a promising alternative cultivar.

  15. POLY-SCALE REFINABLE FUNCTION AND THEIR PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    YANG Shou-zhi

    2006-01-01

    Poly-scale refinable function with dilation factor a is introduced. The existence of solution of poly-scale refinable equation is investigated. Specially, necessary and sufficient conditions for the orthonormality of solution function φ of poly-scale refinable equation with integer dilation factor a are established. Some properties of poly-scale refinable function are discussed. Several examples illustrating how to use the method to construct poly-scale refinable function are given.

  16. Altered Functional Connectivity in Essential Tremor: A Resting-State fMRI Study.

    Science.gov (United States)

    Benito-León, Julián; Louis, Elan D; Romero, Juan Pablo; Hernández-Tamames, Juan Antonio; Manzanedo, Eva; Álvarez-Linera, Juan; Bermejo-Pareja, Félix; Posada, Ignacio; Rocon, Eduardo

    2015-12-01

    Essential tremor (ET) has been associated with a spectrum of clinical features, with both motor and nonmotor elements, including cognitive deficits. We employed resting-state functional magnetic resonance imaging (fMRI) to assess whether brain networks that might be involved in the pathogenesis of nonmotor manifestations associated with ET are altered, and the relationship between abnormal connectivity and ET severity and neuropsychological function.Resting-state fMRI data in 23 ET patients (12 women and 11 men) and 22 healthy controls (HC) (12 women and 10 men) were analyzed using independent component analysis, in combination with a "dual-regression" technique, to identify the group differences of resting-state networks (RSNs) (default mode network [DMN] and executive, frontoparietal, sensorimotor, cerebellar, auditory/language, and visual networks). All participants underwent a neuropsychological and neuroimaging session, where resting-state data were collected.Relative to HC, ET patients showed increased connectivity in RSNs involved in cognitive processes (DMN and frontoparietal networks) and decreased connectivity in the cerebellum and visual networks. Changes in network integrity were associated not only with ET severity (DMN) and ET duration (DMN and left frontoparietal network), but also with cognitive ability. Moreover, in at least 3 networks (DMN and frontoparietal networks), increased connectivity was associated with worse performance on different cognitive domains (attention, executive function, visuospatial ability, verbal memory, visual memory, and language) and depressive symptoms. Further, in the visual network, decreased connectivity was associated with worse performance on visuospatial ability.ET was associated with abnormal brain connectivity in major RSNs that might be involved in both motor and nonmotor symptoms. Our findings underscore the importance of examining RSNs in this population as a biomarker of disease.

  17. Glucocorticoid-Induced Fetal Programming Alters the Functional Complement of Angiotensin Receptors Subtypes within the Kidney

    Science.gov (United States)

    Gwathmey, TanYa M.; Shaltout, Hossam A.; Rose, James C.; Diz, Debra I.; Chappell, Mark C.

    2011-01-01

    We examined the impact of fetal programming on the functional responses of renal angiotensin receptors. Fetal sheep were exposed in utero to betamethasone (BMX; 0.17 mg/kg) or control (CON) at 80–81 days gestation with full term delivery. Renal nuclear and plasma membrane fractions were isolated from 1.0–1.5 year old sheep for receptor binding and fluorescence detection of reactive oxygen species (ROS) or nitric oxide (NO). Mean arterial blood pressure and blood pressure variability were significantly higher in the BMX-exposed adult offspring versus control (CON) sheep. The proportion of nuclear AT1 receptors sensitive to losartan (LOS) was 2-fold higher [67 ± 6% vs. 27 ± 9%, p < 0.01] in BMX compared to control. In contrast, the proportion of AT2 sites was only one-third that of controls (BMX: 25 ± 11% vs. CON: 78 ± 4%, p < 0.01) with a similar reduction in sites sensitive to the Ang-(1-7) antagonist D-Ala7-Ang-(1-7) with BMX exposure. Functional studies revealed that Ang II stimulated ROS to a greater extent in BMX than control sheep (16 ± 3% vs. 6 ± 4%; P<0.05); however NO production to Ang II was attenuated in BMX (26 ± 7% vs. 82 ± 14%; P<0.05). BMX-exposure was also associated with a reduction in the Ang-(1-7) NO response [75 ± 8% vs. 131 ± 26%; P<0.05]. We conclude that altered expression of angiotensin receptor subtypes may be one mechanism whereby functional changes in NO- and ROS-dependent signaling pathways may favor the sustained increase in blood pressure evident in fetal programming. PMID:21220702

  18. Temporal alterations in cardiac fibroblast function following induction of pressure overload

    Science.gov (United States)

    Stewart, James A.; Massey, Erin P.; Fix, Charity; Zhu, Jinyu; Goldsmith, Edie C.

    2014-01-01

    Increases in cardiovascular load (pressure overload) are known to elicit ventricular remodeling including cardiomyocyte hypertrophy and interstitial fibrosis. While numerous studies have focused on the mechanisms of myocyte hypertrophy, comparatively little is known regarding the response of the interstitial fibroblasts to increased cardiovascular load. Fibroblasts are the most numerous cell type in the mammalian myocardium and have long been recognized as producing the majority of the myocardial extracellular matrix. It is only now becoming appreciated that other aspects of fibroblast behavior are important to overall cardiac function. The present studies were performed to examine the temporal alterations in fibroblast activity in response to increased cardiovascular load. Rat myocardial fibroblasts were isolated at specific time-points (3, 7, 14, and 28 days) after induction of pressure overload by abdominal aortic constriction. Bioassays were performed to measure specific parameters of fibroblast function including remodeling and contraction of 3-dimensional collagen gels, migration, and proliferation. In addition, the expression of extracellular matrix receptors of the integrin family was examined. Myocardial hypertrophy and fibrosis were evident within 7 days after constriction of the abdominal aorta. Collagen gel contraction, migration, and proliferation were enhanced in fibroblasts from pressure-overloaded animals compared to fibroblasts from sham animals. Differences in fibroblast function and protein expression were evident within 7 days of aortic constriction, concurrent with the onset of hypertrophy and fibrosis of the intact myocardium. These data provide further support for the idea that rapid and dynamic changes in fibroblast phenotype accompany and contribute to the progression of cardiovascular disease. PMID:20217135

  19. Physical characterization of functionalized spider silk: electronic and sensing properties

    OpenAIRE

    Eden Steven, Jin Gyu Park, Anant Paravastu, Elsa Branco Lopes, James S Brooks, Ongi Englander, Theo Siegrist, Papatya Kaner and Rufina G Alamo

    2011-01-01

    This work explores functional, fundamental and applied aspects of naturally harvested spider silk fibers. Natural silk is a protein polymer where different amino acids control the physical properties of fibroin bundles, producing, for example, combinations of β-sheet (crystalline) and amorphous (helical) structural regions. This complexity presents opportunities for functional modification to obtain new types of material properties. Electrical conductivity is the starting point of this invest...

  20. Jatropha seed protein functional properties for technical applications

    NARCIS (Netherlands)

    Lestari, D.; Mulder, W.J.; Sanders, J.P.M.

    2011-01-01

    Jatropha press cake, by-product after oil expression from Jatropha seeds, contains 24–28% protein on dry basis. Objectives of this research were to investigate functional properties, such as solubility, emulsifying, foaming, film forming, and adhesive properties, of Jatropha press cake proteins and

  1. Basis Function Sampling for Material Property Computations

    Science.gov (United States)

    Whitmer, Jonathan K.; Chiu, Chi-Cheng; Joshi, Abhijeet A.; de Pablo, Juan J.

    2014-03-01

    Wang-Landau sampling, and the associated class of flat histogram simulation methods, have been particularly successful for free energy calculations in a wide array of physical systems. Practically, the convergence of these calculations to a target free energy surface is hampered by reliance on parameters which are unknown a priori. We derive and implement a method based on orthogonal (basis) functions which is fast, parameter-free, and geometrically robust. An important feature of this method is its ability to achieve arbitrary levels of description for the free energy. It is thus ideally suited to in silico measurement of elastic moduli and other quantities related to free energy perturbations. We demonstrate the utility of such applications by applying our method to calculation of the Frank elastic constants of the Lebwohl-Lasher model.

  2. Dynamic wettability alteration in immiscible two-phase flow in porous media: Effect on transport properties and critical slowing down

    Directory of Open Access Journals (Sweden)

    Vegard eFlovik

    2015-11-01

    Full Text Available The change in contact angles due to the injection of low salinity water or any other wettability altering agent in an oil-rich porous medium is modeled by a network model of disordered pores transporting two immiscible fluids. We introduce a dynamic wettability altering mechanism, where the time dependent wetting property of each pore is determined by the cumulative flow of water through it. Simulations are performed to reach steady-state for different possible alterations in the wetting angle (θ. We find that deviation from oil-wet conditions re-mobilizes the stuck clusters and increases the oil fractional flow. However, the rate of increase in the fractional flow depends strongly on θ and as θ → 90◦ , a critical angle, the system shows critical slowing down which is characterized by two dynamic critical exponents.

  3. Dynamic wettability alteration in immiscible two-phase flow in porous media: Effect on transport properties and critical slowing down

    CERN Document Server

    Flovik, Vegard; Hansen, Alex

    2015-01-01

    The change in contact angles due to the injection of low salinity water or any other wettability altering agent in an oil-rich porous medium is modeled by a network model of disordered pores transporting two immiscible fluids. We introduce a dynamic wettability altering mechanism, where the time dependent wetting property of each pore is determined by the cumulative flow of water through it. Simulations are performed to reach steady-state for different possible alterations in the wetting angle ($\\theta$). We find that deviation from oil-wet conditions re-mobilizes the stuck clusters and increases the oil fractional flow. However, the rate of increase in the fractional flow depends strongly on $\\theta$ and as $\\theta\\to 90^\\circ$, a critical angle, the system shows critical slowing down which is characterized by two dynamic critical exponents.

  4. Altered Functional Connectivity in Patients with Subcortical Vascular Cognitive Impairment--A Resting-State Functional Magnetic Resonance Imaging Study.

    Directory of Open Access Journals (Sweden)

    Weina Ding

    Full Text Available Recent neuroimaging studies have shown that people with subcortical vascular cognitive impairment (sVCI have structural and functional abnormalities in the frontal lobe and subcortical brain sites. In this study, we used seed-based resting-state functional connectivity (rsFC analysis and voxel-mirrored homotopic connectivity (VMHC techniques to investigate the alteration of rsFC in patients with sVCI. rsFC and structural magnetic resonance images were acquired for 51 patients with subcortical cerebrovascular disease. All patients were subdivided based on cognitive status into 29 with sVCI and 22 controls; patient characteristics were matched. rsFC of the posterior cingulate cortex (PCC and VMHC were calculated separately, and rsFC of the PCC and VMHC between the two groups were compared. The regions showing abnormal rsFC of the PCC or VMHC in sVCI patients were adopted as regions of interest for correlation analyses. Our results are as follows: The patients with sVCI exhibited increases in rsFC in the left middle temporal lobe, right inferior temporal lobe and left superior frontal gyrus, and significant decreases in rsFC of the left thalamus with the PCC. sVCI patients showed a significant deficit in VMHC between the bilateral lingual gyrus, putamen, and precentral gyrus. Additionally, the z-memory score was significantly positively associated with connectivity between the left thalamus and the PCC (r = 0.41, p = 0.03, uncorrected in the sVCI group. Our findings suggest that the frontal lobe and subcortical brain sites play an important role in the pathogenesis of sVCI. Furthermore, rsFC between the left thalamus and the PCC might indicate the severity of sVCI.

  5. Modular properties of full 5D SYM partition function

    CERN Document Server

    Qiu, Jian; Winding, Jacob; Zabzine, Maxim

    2015-01-01

    We study properties of the full partition function for the $U(1)$ 5D $\\mathcal{N}=2^*$ gauge theory with adjoint hypermultiplet of mass $M$. This theory is ultimately related to abelian 6D (2,0) theory. We construct the full non-perturbative partition function on toric Sasaki-Einstein manifolds by gluing flat copies of the Nekrasov partition function and we express the full partition function in terms of the generalized double elliptic gamma function $G_2^C$ associated with a certain moment map cone $C$. The answer exhibits a curious $SL(4,\\mathbb{Z})$ modular property. Finally, we propose a set of rules to construct the partition function that resembles the calculation of 5D supersymmetric partition function with the insertion of defects of various co-dimensions.

  6. Modular properties of full 5D SYM partition function

    Science.gov (United States)

    Qiu, Jian; Tizzano, Luigi; Winding, Jacob; Zabzine, Maxim

    2016-03-01

    We study properties of the full partition function for the U(1) 5D N = {2}^{ast } gauge theory with adjoint hypermultiplet of mass M . This theory is ultimately related to abelian 6D (2,0) theory. We construct the full non-perturbative partition function on toric Sasaki-Einstein manifolds by gluing flat copies of the Nekrasov partition function and we express the full partition function in terms of the generalized double elliptic gamma function G 2 C associated with a certain moment map cone C. The answer exhibits a curious SL(4 , ℤ) modular property. Finally, we propose a set of rules to construct the partition function that resembles the calculation of 5d supersymmetric partition function with the insert ion of defects of various co-dimensions.

  7. c-Myc Alters Substrate Utilization and O-GlcNAc Protein Posttranslational Modifications without Altering Cardiac Function during Early Aortic Constriction.

    Directory of Open Access Journals (Sweden)

    Dolena Ledee

    Full Text Available Hypertrophic stimuli cause transcription of the proto-oncogene c-Myc (Myc. Prior work showed that myocardial knockout of c-Myc (Myc attenuated hypertrophy and decreased expression of metabolic genes after aortic constriction. Accordingly, we assessed the interplay between Myc, substrate oxidation and cardiac function during early pressure overload hypertrophy. Mice with cardiac specific, inducible Myc knockout (MycKO-TAC and non-transgenic littermates (Cont-TAC were subjected to transverse aortic constriction (TAC; n = 7/group. Additional groups underwent sham surgery (Cont-Sham and MycKO-Sham, n = 5 per group. After two weeks, function was measured in isolated working hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketone bodies and unlabeled glucose and insulin. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. In sham hearts, Myc knockout did not affect cardiac function or substrate preferences for the citric acid cycle. However, Myc knockout altered fractional contributions during TAC. The unlabeled fractional contribution increased in MycKO-TAC versus Cont-TAC, whereas ketone and free fatty acid fractional contributions decreased. Additionally, protein posttranslational modifications by O-GlcNAc were significantly greater in Cont-TAC versus both Cont-Sham and MycKO-TAC. In conclusion, Myc alters substrate preferences for the citric acid cycle during early pressure overload hypertrophy without negatively affecting cardiac function. Myc also affects protein posttranslational modifications by O-GlcNAc during hypertrophy, which may regulate Myc-induced metabolic changes.

  8. The modifications of bovine β-lactoglobulin: Effects on its structural and functional properties

    Directory of Open Access Journals (Sweden)

    Stanić-Vučinić Dragana

    2013-01-01

    Full Text Available Beta-lactoglobulin (BLG is the main whey protein and it is frequently used additive in wide range of food products due to its excellent techno-functional properties, high nutritional value and low cost. It is also considered as acid-resistant drug carrier for delivery of pharmaceutical and nutraceutical agents. However, BLG is the main allergen of milk. A variety of methods have been explored for modification of BLG in attempt to improve its functional properties and to decrease its allergenicity. Due to its compact globular structure BLG is relatively resistant to modifications, especially under mild conditions. BLG can be modified by physical, chemical and enzymatic treatments. Although chemical modifications offer efficient way of alteration of protein structural and functional properties, they are associated with safety concern. In the last decade there is a tendency for application of novel non-thermal physical processing methods, as well as enzymes in order to obtain BLG with desirable properties. The objective of this review is to overview chemical, physical and enzymatic processing techniques utilized to modify BLG and their effects on structure and functional properties of BLG. [Projekat Ministarstva nauke Republike Srbije, br. 172024 and FP7 RegPot project FCUB ERA GA No. 256716

  9. Exercise challenge in Gulf War Illness reveals two subgroups with altered brain structure and function.

    Directory of Open Access Journals (Sweden)

    Rakib U Rayhan

    Full Text Available Nearly 30% of the approximately 700,000 military personnel who served in Operation Desert Storm (1990-1991 have developed Gulf War Illness, a condition that presents with symptoms such as cognitive impairment, autonomic dysfunction, debilitating fatigue and chronic widespread pain that implicate the central nervous system. A hallmark complaint of subjects with Gulf War Illness is post-exertional malaise; defined as an exacerbation of symptoms following physical and/or mental effort. To study the causal relationship between exercise, the brain, and changes in symptoms, 28 Gulf War veterans and 10 controls completed an fMRI scan before and after two exercise stress tests to investigate serial changes in pain, autonomic function, and working memory. Exercise induced two clinical Gulf War Illness subgroups. One subgroup presented with orthostatic tachycardia (n = 10. This phenotype correlated with brainstem atrophy, baseline working memory compensation in the cerebellar vermis, and subsequent loss of compensation after exercise. The other subgroup developed exercise induced hyperalgesia (n = 18 that was associated with cortical atrophy and baseline working memory compensation in the basal ganglia. Alterations in cognition, brain structure, and symptoms were absent in controls. Our novel findings may provide an understanding of the relationship between the brain and post-exertional malaise in Gulf War Illness.

  10. Exercise challenge in Gulf War Illness reveals two subgroups with altered brain structure and function.

    Science.gov (United States)

    Rayhan, Rakib U; Stevens, Benson W; Raksit, Megna P; Ripple, Joshua A; Timbol, Christian R; Adewuyi, Oluwatoyin; VanMeter, John W; Baraniuk, James N

    2013-01-01

    Nearly 30% of the approximately 700,000 military personnel who served in Operation Desert Storm (1990-1991) have developed Gulf War Illness, a condition that presents with symptoms such as cognitive impairment, autonomic dysfunction, debilitating fatigue and chronic widespread pain that implicate the central nervous system. A hallmark complaint of subjects with Gulf War Illness is post-exertional malaise; defined as an exacerbation of symptoms following physical and/or mental effort. To study the causal relationship between exercise, the brain, and changes in symptoms, 28 Gulf War veterans and 10 controls completed an fMRI scan before and after two exercise stress tests to investigate serial changes in pain, autonomic function, and working memory. Exercise induced two clinical Gulf War Illness subgroups. One subgroup presented with orthostatic tachycardia (n = 10). This phenotype correlated with brainstem atrophy, baseline working memory compensation in the cerebellar vermis, and subsequent loss of compensation after exercise. The other subgroup developed exercise induced hyperalgesia (n = 18) that was associated with cortical atrophy and baseline working memory compensation in the basal ganglia. Alterations in cognition, brain structure, and symptoms were absent in controls. Our novel findings may provide an understanding of the relationship between the brain and post-exertional malaise in Gulf War Illness.

  11. Radionuclide assessment of stunned myocardium by alterations in perfusion, metabolism and function

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Tsunehiko; Uehara, Toshiisa (National Cardiovascular Center, Suita, Osaka (Japan)); Strauss, H.W.

    1991-09-01

    A method for the diagnosis of stunned myocardium has not yet been established, although it has been retrospectively demonstrated in patients after intracoronary thrombolysis, unstable angina, and coronary revascularization. In this study, radionuclide cardiac imaging was carried out to evaluate the existence of stunned myocardium. Gated blood pool scanning was performed in patients undergoing intracoronary thrombolysis both at the time of reperfusion (Rp) and 10 days later. In the Rp<4 h group, about half of the initially abnormal segments showed complete improvement on quantitative wall motion analysis, which was more than in the Rp>4 h and control groups. In patients with acute myocardial ischemia, the correlation between thallium perfusion and regional wall motion was assessed semiquantitatively. In unstable angina, 5.8% of the ventricular wall segments showed dissociation between perfusion and wall motion (well-perfused asynergy). These segments had abnormal wall motion although perfusion was maintained, and were thought to be areas of stunned myocardium. Fourteen dogs were studied using thallium and {sup 123}I-{beta}-methyl-iodophenyl pentadecanoic acid (BMIPP) fatty acid imaging to evaluate the relationship of perfusion to metabolism. In the reperfusion model, mismatching of the pattern of thallium and BMIPP uptake was observed. Reperfused myocardium probably has an increased triglyceride content, which is related to the degree of myocardial viability. In conclusion, stunned myocardium may be correctly diagnosed acutely on the basis of alterations in its perfusion, metabolism, and function by using radionuclide cardiac imaging. (author).

  12. Entamoeba histolytica contains an occludin-like protein that can alter colonic epithelial barrier function.

    Science.gov (United States)

    Goplen, Michael; Lejeune, Manigandan; Cornick, Steve; Moreau, France; Chadee, Kris

    2013-01-01

    The exact mechanism by which Entamoeba histolytica disrupts the human colonic epithelium and invades the mucosa has yet to be clearly elucidated. E. histolytica produces a diverse array of putative virulent factors such as glycosidase, cysteine proteinases and amebapore that can modulate and/or disrupt epithelial barrier functions. However, it is currently thought that E. histolytica produces numerous other molecules and strategies to disrupt colonic mucosal defenses. In this study, we document a putative mechanism whereby the parasite alters the integrity of human epithelium by expressing a cognate tight junction protein of the host. We detected this protein as "occludin-like" as revealed by immunoblotting and immunoprecipitation studies and visualization by confocal microscopy using antibodies highly specific for human occludin. We propose that E. histolytica occludin-like protein might displace mucosal epithelial occludin-occludin tight junction interactions resulting in epithelial disruption analogous to sub mucosal human dendritic cells sampling luminal contents. These results indicate that E. histolytica occludin is a putative virulent component that can play a role in the pathogenesis of intestinal amebiasis.

  13. Overexpression of mitochondrial sirtuins alters glycolysis and mitochondrial function in HEK293 cells.

    Directory of Open Access Journals (Sweden)

    Michelle Barbi de Moura

    Full Text Available SIRT3, SIRT4, and SIRT5 are mitochondrial deacylases that impact multiple facets of energy metabolism and mitochondrial function. SIRT3 activates several mitochondrial enzymes, SIRT4 represses its targets, and SIRT5 has been shown to both activate and repress mitochondrial enzymes. To gain insight into the relative effects of the mitochondrial sirtuins in governing mitochondrial energy metabolism, SIRT3, SIRT4, and SIRT5 overexpressing HEK293 cells were directly compared. When grown under standard cell culture conditions (25 mM glucose all three sirtuins induced increases in mitochondrial respiration, glycolysis, and glucose oxidation, but with no change in growth rate or in steady-state ATP concentration. Increased proton leak, as evidenced by oxygen consumption in the presence of oligomycin, appeared to explain much of the increase in basal oxygen utilization. Growth in 5 mM glucose normalized the elevations in basal oxygen consumption, proton leak, and glycolysis in all sirtuin over-expressing cells. While the above effects were common to all three mitochondrial sirtuins, some differences between the SIRT3, SIRT4, and SIRT5 expressing cells were noted. Only SIRT3 overexpression affected fatty acid metabolism, and only SIRT4 overexpression altered superoxide levels and mitochondrial membrane potential. We conclude that all three mitochondrial sirtuins can promote increased mitochondrial respiration and cellular metabolism. SIRT3, SIRT4, and SIRT5 appear to respond to excess glucose by inducing a coordinated increase of glycolysis and respiration, with the excess energy dissipated via proton leak.

  14. Exposure to acetylcholinesterase inhibitors alters the physiology and motor function of honeybees

    Directory of Open Access Journals (Sweden)

    Sally M Williamson

    2013-02-01

    Full Text Available Cholinergic signalling is fundamental to neuro-muscular function in most organisms. Sub-lethal doses of neurotoxic pesticides that target cholinergic signalling can alter the behaviour of insects in subtle ways; their influence on non-target organisms may not be readily apparent in simple mortality studies. Beneficial arthropods such as honeybees perform sophisticated behavioural sequences during foraging that, if influenced by pesticides, could impair foraging success and reduce colony health. Here, we investigate the behavioural effects on honeybees of exposure to a selection of pesticides that target cholinergic signalling by inhibiting acetylcholinesterase (AChE. To examine how continued exposure to AChE inhibitors affected motor function, we fed adult foraging worker honeybees sub-lethal concentrations of these compounds in sucrose solution for 24 h. Using an assay for locomotion in bees, we scored walking, stopped, grooming, and upside down behaviour continuously for 15 min. At a 10nM concentration, all the AChE inhibitors caused similar effects on behaviour, notably increased grooming activity and changes in the frequency of bouts of behaviour such as head grooming. Coumaphos caused dose-dependent effects on locomotion as well as grooming behaviour, and a 1µM concentration of coumaphos induced symptoms of malaise such as abdomen grooming and defecation. Biochemical assays confirmed that the 4 compounds we assayed (coumaphos, aldicarb, chlorpyrifos, and donepezil or their metabolites acted as AChE inhibitors in bees. Furthermore, we show that transcript expression levels of two honeybee acetylcholinesterase inhibitors were selectively upregulated in the brain and in gut tissues in response to AChE inhibitor exposure. The results of our study imply that the effects of pesticides that rely on this mode of action have subtle yet profound effects on physiological effects on behaviour that could lead to reduced survival.

  15. STN1 OB Fold Mutation Alters DNA Binding and Affects Selective Aspects of CST Function

    Science.gov (United States)

    Bhattacharjee, Anukana; Stewart, Jason; Chaiken, Mary; Price, Carolyn M.

    2016-01-01

    Mammalian CST (CTC1-STN1-TEN1) participates in multiple aspects of telomere replication and genome-wide recovery from replication stress. CST resembles Replication Protein A (RPA) in that it binds ssDNA and STN1 and TEN1 are structurally similar to RPA2 and RPA3. Conservation between CTC1 and RPA1 is less apparent. Currently the mechanism underlying CST action is largely unknown. Here we address CST mechanism by using a DNA-binding mutant, (STN1 OB-fold mutant, STN1-OBM) to examine the relationship between DNA binding and CST function. In vivo, STN1-OBM affects resolution of endogenous replication stress and telomere duplex replication but telomeric C-strand fill-in and new origin firing after exogenous replication stress are unaffected. These selective effects indicate mechanistic differences in CST action during resolution of different replication problems. In vitro binding studies show that STN1 directly engages both short and long ssDNA oligonucleotides, however STN1-OBM preferentially destabilizes binding to short substrates. The finding that STN1-OBM affects binding to only certain substrates starts to explain the in vivo separation of function observed in STN1-OBM expressing cells. CST is expected to engage DNA substrates of varied length and structure as it acts to resolve different replication problems. Since STN1-OBM will alter CST binding to only some of these substrates, the mutant should affect resolution of only a subset of replication problems, as was observed in the STN1-OBM cells. The in vitro studies also provide insight into CST binding mechanism. Like RPA, CST likely contacts DNA via multiple OB folds. However, the importance of STN1 for binding short substrates indicates differences in the architecture of CST and RPA DNA-protein complexes. Based on our results, we propose a dynamic DNA binding model that provides a general mechanism for CST action at diverse forms of replication stress. PMID:27690379

  16. Impact of ultraviolet-B radiation on planktonic fish larvae: Alteration of the osmoregulatory function

    Energy Technology Data Exchange (ETDEWEB)

    Sucre, Elliott, E-mail: elliott.sucre@univ-montp2.fr [AEO Team (Adaptation Ecophysiologique et Ontogenese), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc092, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Vidussi, Francesca [RESEAUX Team (Reseaux Planctoniques et Changement Environnemental), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc093, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Mostajir, Behzad [RESEAUX Team (Reseaux Planctoniques et Changement Environnemental), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc093, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Centre d' ecologie marine experimentale MEDIMEER (Mediterranean centre for Marine Ecosystem Experimental Research), Universite Montpellier 2-CNRS (UMS 3301), Station Mediterraneenne de l' Environnement Littoral, MEDIMEER, 2 Rue des Chantiers, 34200 Sete (France); Charmantier, Guy; Lorin-Nebel, Catherine [AEO Team (Adaptation Ecophysiologique et Ontogenese), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc092, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France)

    2012-03-15

    Coastal marine ecosystems are submitted to variations of several abiotic and biotic parameters, some of them related to global change. Among them the ultraviolet-B (UV-B) radiation (UVBR: 280-320 nm) may strongly impact planktonic fish larvae. The consequences of an increase of UVBR on the osmoregulatory function of Dicentrarchus labrax larvae have been investigated in this study. In young larvae of D. labrax, as in other teleosts, osmoregulation depends on tegumentary ion transporting cells, or ionocytes, mainly located on the skin of the trunk and of the yolk sac. As early D. labrax larvae passively drift in the top water column, ionocytes are exposed to solar radiation. The effect of UVBR on larval osmoregulation in seawater was evaluated through nanoosmometric measurements of the blood osmolality after exposure to different UV-B treatments. A loss of osmoregulatory capability occured in larvae after 2 days of low (50 {mu}W cm{sup -2}: 4 h L/20 h D) and medium (80 {mu}W cm{sup -2}: 4 h L/20 h D) UVBR exposure. Compared to control larvae kept in the darkness, a significant increase in blood osmolality, abnormal behavior and high mortalities were detected in larvae exposed to UVBR from 2 days on. At the cellular level, an important decrease in abundance of tegumentary ionocytes and mucous cells was observed after 2 days of exposure to UVBR. In the ionocytes, two major osmoeffectors were immunolocalized, the Na{sup +}/K{sup +}-ATPase and the Na{sup +}/K{sup +}/2Cl{sup -} cotransporter. Compared to controls, the fluorescent immunostaining was lower in UVBR-exposed larvae. We hypothesize that the impaired osmoregulation in UVBR-exposed larvae originates from the lower number of tegumentary ionocytes and mucous cells. This alteration of the osmoregulatory function could negatively impact the survival of young larvae at the surface water exposed to UVBR.

  17. Altered Default Network Resting State Functional Connectivity in Patients with a First Episode of Psychosis

    Science.gov (United States)

    Alonso-Solís, Anna; Corripio, Iluminada; de Castro-Manglano, Pilar; Duran-Sindreu, Santiago; Garcia-Garcia, Manuel; Proal, Erika; Nuñez-Marín, Fidel; Soutullo, Cesar; Alvarez, Enric; Gómez-Ansón, Beatriz; Kelly, Clare; Castellanos, F. Xavier

    2012-01-01

    Background Default network (DN) abnormalities have been identified in patients with chronic schizophrenia using “resting state” functional magnetic resonance imaging (R-fMRI). Here, we examined the integrity of the DN in patients experiencing their first episode of psychosis (FEP) compared with sex- and age-matched healthy controls. Methods We collected R-fMRI data from 19 FEP patients (mean age 24.9±4.8 yrs, 14 males) and 19 healthy controls (26.1±4.8 yrs, 14 males) at 3 Tesla. Following standard preprocessing, we examined the functional connectivity (FC) of two DN subsystems and the two DN hubs (P<0.0045, corrected). Results Patients with FEP exhibited abnormal FC that appeared largely restricted to the dorsomedial prefrontal cortex (dMPFC) DN subsystem. Relative to controls, FEP patients exhibited weaker positive FC between dMPFC and posterior cingulate cortex (PCC) and precuneus, extending laterally through the parietal lobe to the posterior angular gyrus. Patients with FEP exhibited weaker negative FC between the lateral temporal cortex and the intracalcarine cortex, bilaterally. The PCC and temporo-parietal junction also exhibited weaker negative FC with the right fusiform gyrus extending to the lingual gyrus and lateral occipital cortex, in FEP patients, compared to controls. By contrast, patients with FEP showed stronger negative FC between the temporal pole and medial motor cortex, anterior precuneus and posterior mid-cingulate cortex. Conclusions Abnormalities in the dMPFC DN subsystem in patients with a FEP suggest that FC patterns are altered even in the early stages of psychosis. PMID:22633527

  18. Altered lymphocyte proliferation and innate immune function in scrapie 139A- and ME7-infected mice.

    Science.gov (United States)

    Cho, In Soo; Spinner, Daryl S; Kascsak, Richard J; Meeker, H Cliff; Kim, Bo Sook; Park, Seung Yong; Schuller-Levis, Georgia; Park, Eunkyue

    2013-06-01

    Lymphoid organs play an important role in prion disease development and progression. While the role of lymphoid organs and changes in immune-related genes have been extensively investigated in scrapie-infected animals, innate immunity has not. Previous studies examined lymphocyte function in scrapie-infected C3H/HeJ mice, which exhibit defects in lipopolysaccharide (LPS) response now known to result from a mutation in Toll-like receptor (TLR) 4. We examined immune function in scrapie-infected CD1 mice, which are LPS responders. Lymphocyte proliferation from CD1 mice infected with either 139A or ME7 scrapie was measured in response to concanavalin (Con) A or LPS at 1 and 3 months after infection. Following LPS exposure, mice infected 3 months with ME7, but not 139A, demonstrated significantly decreased lymphocyte proliferation compared to controls. After Con A exposure, lymphocyte proliferation in scrapie-infected mice did not differ from controls. Gender-specific comparison of lymphocyte proliferation showed significant decreases in mitogenic responses in females infected 3 months with either 139A or ME7, compared to controls. Males infected for 3 months with ME7, but not 139A, showed significantly decreased proliferation after lymphocyte exposure to LPS, but not Con A. Neither gender showed changes in lymphocyte proliferation after 1 month of scrapie infection. Innate immune activation of peritoneal macrophages was determined via production of nitric oxide (NO), IL-6, and TNF-α after exposure to TLR ligands. TNF-α and IL-6 production were reduced in macrophages from females infected with either scrapie strain for 3 months, while NO production after TLR agonist plus IFN-γ exposure was decreased in both females and males infected for 3 months with 139A, compared to ME7. These data demonstrated altered innate immunity, suggesting hormonal and/or other gender-specific regulation may contribute to gender differences in some immune functions. Our data demonstrate

  19. Structure-Function-Property-Design Interplay in Biopolymers: Spider Silk

    Science.gov (United States)

    Tokareva, Olena; Jacobsen, Matthew; Buehler, Markus; Wong, Joyce; Kaplan, David L.

    2013-01-01

    Spider silks have been a focus of research for almost two decades due to their outstanding mechanical and biophysical properties. Recent advances in genetic engineering have led to the synthesis of recombinant spider silks, thus helping to unravel a fundamental understanding of structure-function-property relationships. The relationships between molecular composition, secondary structures, and mechanical properties found in different types of spider silks are described, along with a discussion of artificial spinning of these proteins and their bioapplications, including the role of silks in biomineralization and fabrication of biomaterials with controlled properties. PMID:23962644

  20. Structure-function-property-design interplay in biopolymers: spider silk.

    Science.gov (United States)

    Tokareva, Olena; Jacobsen, Matthew; Buehler, Markus; Wong, Joyce; Kaplan, David L

    2014-04-01

    Spider silks have been a focus of research for almost two decades due to their outstanding mechanical and biophysical properties. Recent advances in genetic engineering have led to the synthesis of recombinant spider silks, thus helping to unravel a fundamental understanding of structure-function-property relationships. The relationships between molecular composition, secondary structures and mechanical properties found in different types of spider silks are described, along with a discussion of artificial spinning of these proteins and their bioapplications, including the role of silks in biomineralization and fabrication of biomaterials with controlled properties.

  1. THE PITS PROPERTY OF ENTIRE FUNCTIONS DEFINED BY DIRICHLET SERIES

    Institute of Scientific and Technical Information of China (English)

    Shang Lina; Gao Zongsheng

    2009-01-01

    The value distribution of entire functions defined by Dirichlet series are studied in this present article. It is proved that entire functions defined by Dirichlet series have the pits property, which improve the relative results on lacunary Taylor series obtained by Littlewood J.E. and Offord A.C.

  2. Alteration of plant meristem function by manipulation of the Retinoblastoma-like plant RRB gene

    Science.gov (United States)

    Durfee, Tim; Feiler, Heidi; Gruissem, Wilhelm; Jenkins, Susan; Roe, Judith; Zambryski, Patricia

    2007-01-16

    This invention provides methods and compositions for altering the growth, organization, and differentiation of plant tissues. The invention is based on the discovery that, in plants, genetically altering the levels of Retinoblastoma-related gene (RRB) activity produces dramatic effects on the growth, proliferation, organization, and differentiation of plant meristem.

  3. Altered time structure of neuro-endocrine-immune system function in lung cancer patients

    Directory of Open Access Journals (Sweden)

    Carughi Stefano

    2010-06-01

    TcS1 was decreased in cancer patients. The melatonin/cortisol mean nocturnal level ratio was decreased in cancer patients. Conclusion The altered secretion and loss of circadian rhythmicity of many studied factors observed in the subjects suffering from neoplastic disease may be expression of gradual alteration of the integrated function of the neuro-immune-endocrine system

  4. Properties of squeezing functions and geometry of bounded domains

    CERN Document Server

    Deng, Fusheng; Zhang, Liyou

    2012-01-01

    In this article we continue the study of properties of squeezing functions and geometry of bounded domains. The limit of squeezing functions of a sequence of bounded domains is studied. We give comparisons of intrinsic positive forms and metrics on bounded domains in terms of squeezing functions. To study the boundary behavior of squeezing functions, we introduce the notions of (intrinsic) ball pinching radius, and give boundary estimate of squeezing functions in terms of these datum. Finally, we use these results to study geometric and analytic properties of some interesting domains, including planar domains, Cartan-Hartogs domains, and a strongly pseudoconvex Reinhardt domain which is not convex. As a corollary, all Cartan-Hartogs domains are homogenous regular, i.e., their squeezing functions admit positive lower bounds.

  5. Alterations of intestinal mucosa structure and barrier function following traumatic brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    Chun-Hua Hang; Ji-Xin Shi; Jie-Shou Li; Wei Wu; Hong-Xia Yin

    2003-01-01

    AIM: Gastrointestinal dysfunction is a common complication in patients with traumatic brain injury (TBI). However, the effect of traumatic brain injury on intestinal mucosa has not been studied previously. The aim of the current study was to explore the alterations of intestinal mucosa morphology and barrier function, and to determine how rapidly the impairment of gut barrier function occurs and how long it persists following traumatic brain injury.METHODS: Male Wistar rats were randomly divided into six groups (6 rats each group) including controls without brain injury and traumatic brain injury groups at hours 3,12, 24, and 72, and on day 7. The intestinal mucosa structure was detected by histopathological examination and electron microscopy. Gut barrier dysfunction was evaluated by detecting serum endotoxin and intestinal permeability. The level of serum endotoxin and intestinal permeability was measured by using chromogenic limulus amebocyte lysate and lactulose/mannitol (L/M) ratio, respectively.RESULTS: After traumatic brain injury, the histopathological alterations of gut mucosa occurred rapidly as early as 3 hours and progressed to a serious state, including shedding of epithelial cells, fracture of villi, focal ulcer, fusion of adjacent villi, dilation of central chyle duct, mucosal atrophy,and vascular dilation, congestion and edema in the villous interstitium and lamina propria. Apoptosis of epithelial cells,fracture and sparseness of microvilli, loss of tight junction between enterocytes, damage of mitochondria and endoplasm, were found by electron microscopy. The villous height, crypt depth and surface area in jejunum decreased progressively with the time of brain injury. As compared with that of control group (183.7±41.8 EU/L), serum endotoxin level was signnificantly increased at 3, 12, and 24 hours following TBI (434.8±54.9 EU/L, 324.2±61.7 EU/L and 303.3±60.2 EU/L, respectively), and peaked at 72 hours (560.5±76.2 EU/L), then declined on day 7

  6. Nutritional and functional properties of whey proteins concentrate and isolate

    Directory of Open Access Journals (Sweden)

    Zoran Herceg

    2006-12-01

    Full Text Available Whey protein fractions represent 18 - 20 % of total milk nitrogen content. Nutritional value in addition to diverse physico - chemical and functional properties make whey proteins highly suitable for application in foodstuffs. In the most cases, whey proteins are used because of their functional properties. Whey proteins possess favourable functional characteristics such as gelling, water binding, emulsification and foaming ability. Due to application of new process techniques (membrane fractionation techniques, it is possible to produce various whey - protein based products. The most important products based on the whey proteins are whey protein concentrates (WPC and whey protein isolates (WPI. The aim of this paper was to give comprehensive review of nutritional and functional properties of the most common used whey proteins (whey protein concentrate - WPC and whey protein isolate - WPI in the food industry.

  7. Vaccination with Ad5 vectors expands Ad5-specific CD8 T cells without altering memory phenotype or functionality.

    Directory of Open Access Journals (Sweden)

    Natalie A Hutnick

    Full Text Available BACKGROUND: Adenoviral (Ad vaccine vectors represent both a vehicle to present a novel antigen to the immune system as well as restimulation of immune responses against the Ad vector itself. To what degree Ad-specific CD8(+ T cells are restimulated by Ad vector vaccination is unclear, although such knowledge would be important as vector-specific CD8(+ T cell expansion could potentially further limit Ad vaccine efficacy beyond Ad-specific neutralizing antibody alone. METHODOLOGY/PRINCIPAL FINDINGS: Here we addressed this issue by measuring human Adenovirus serotype 5 (Ad5-specific CD8(+ T cells in recipients of the Merck Ad5 HIV-1 vaccine vector before, during, and after vaccination by multicolor flow cytometry. Ad5-specific CD8(+ T-cells were detectable in 95% of subjects prior to vaccination, and displayed primarily an effector-type functional profile and phenotype. Peripheral blood Ad5-specific CD8(+ T-cell numbers expanded after Ad5-HIV vaccination in all subjects, but differential expansion kinetics were noted in some baseline Ad5-neutralizing antibody (Ad5 nAb seronegative subjects compared to baseline Ad5 nAb seropositive subjects. However, in neither group did vaccination alter polyfunctionality, mucosal targeting marker expression, or memory phenotype of Ad5-specific CD8(+ T-cells. CONCLUSIONS: These data indicate that repeat Ad5-vector administration in humans expands Ad5-specific CD8(+ T-cells without overtly affecting their functional capacity or phenotypic properties. This is a secondary analysis of samples collected during the 016 trial. Results of the Merck 016 trial safety and immunogenicity have been previously published in the journal of clinical infectious diseases [1]. TRIAL REGISTRATION: ClinicalTrials.gov NCT00849680[http://www.clinicaltrials.gov/show/NCT00849680].

  8. Renal pyramid echogenicity in ureteropelvic junction obstruction: correlation between altered echogenicity and differential renal function

    Energy Technology Data Exchange (ETDEWEB)

    Chavhan, Govind; Daneman, Alan; Lim, Ruth; Traubici, Jeffrey [University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto (Canada); Moineddin, Rahim [University of Toronto, Department of Family and Community Medicine, Toronto (Canada); Langlois, Valerie [University of Toronto, Division of Nephrology, Department of Pediatrics, Hospital for Sick Children, Toronto (Canada)

    2008-10-15

    Improvement in resolution and use of high-frequency transducers in US has enabled visualization of previously unreported changes in medullary pyramid echogenicity in children with obstructive hydronephrosis. To determine whether these unreported changes in echogenicity and morphology of the renal pyramids in ureteropelvic junction (UPJ) obstruction correlate with differential renal function (DRF) of the kidney as determined by technetium-99m mercaptoacetyltriglycine ({sup 99m}Tc-MAG3) scan. Renal sonograms in 60 children with UPJ obstruction were retrospectively reviewed. Children were divided into three groups based on the echogenicity of the pyramids: (1) normal echogenicity of the pyramids, (2) increased echogenicity of the pyramids with maintained corticomedullary differentiation (CMD), and (3) loss of CMD. DRF, as determined by {sup 99m}Tc-MAG3 scan, of the obstructed kidney of {>=}45% was considered normal and of {<=}44% was considered abnormal based on a published study correlating histological changes with DRF. Fisher's exact test was performed for assessing the association between DRF and altered echogenicity of the pyramids. In group 1, which consisted of 13 patients with normal pyramids on US, DRF was normal in 11 and abnormal in two. In group 2, which consisted of 33 patients with echogenic pyramids and preserved CMD, DRF was normal in 15 and abnormal in 18. In group 3, which consisted of 14 patients with complete loss of CMD, DRF was normal in 2 and abnormal in 12. There was a strong correlation between abnormal pyramids and DRF (P=0.0009). The risk ratio (RR) of DRF becoming abnormal for those kidneys with abnormal echogenicity of the pyramids with preserved CMD (group 2) compared to normal pyramid echogenicity (group 1) was 1.56 (95% CI 1.088-2.236). The RR of DRF becoming abnormal for those kidneys with loss of CMD (group 3) compared to normal pyramid echogenicity (group 1) was 5.571 (95% CI 1.530-20.294). We observed that in obstructed kidneys

  9. Reduced functionality of PSE-like chicken breast meat batter resulting from alterations in protein conformation.

    Science.gov (United States)

    Li, K; Zhao, Y Y; Kang, Z L; Wang, P; Han, M Y; Xu, X L; Zhou, G H

    2015-01-01

    The objectives of this study were to evaluate protein thermal stability, water-protein interaction, microstructure, and protein conformation between PSE-like and normal chicken breast meat batters. Sixty pale, soft, and exudative (PSE)-like (L*>53, pH24 hbatters were formulated to 14% meat protein and 2% salt, and they were analyzed for the protein changes and the microstructure using differential scanning calorimetry, low-field (LF)-NMR, SEM, and Raman spectroscopy. PSE-like meat batter had lower gel strength, water-holding capacity, and salt-soluble protein extraction (Pbatter formed an aggregated gel matrix, while normal meat batter produced a compact gel network with fine, cross-linked strands by many protein filaments. LF-NMR revealed an increase in the water mobility in heated PSE-like meat batter with an increasing amount of loosely bound water (Pbatter had less unfolded α-helix and β-sheet structure formation, reduced exposure of hydrophobic and tyrosine residues (P<0.05), and changes in the microenvironment of aliphatic residues and tryptophan, which affected salt-soluble protein extraction, gel properties, and water-holding capacity. In conclusion, the inferior functional properties of PSE-like meat were attributed to not only myosin denaturation, but also actin denaturation after salt addition and different protein structural states.

  10. Exploring patterns of alteration in Alzheimer’s disease brain networks: a combined structural and functional connectomics analysis

    Directory of Open Access Journals (Sweden)

    Fulvia Palesi

    2016-09-01

    Full Text Available Alzheimer’s disease (AD is a neurodegenerative disorder characterized by a severe derangement of cognitive functions, primarily memory, in elderly subjects. As far as the functional impairment is concerned, growing evidence supports the disconnection syndrome hypothesis. Recent investigations using fMRI have revealed a generalized alteration of resting state networks in patients affected by AD and mild cognitive impairment (MCI. However, it was unclear whether the changes in functional connectivity were accompanied by corresponding structural network changes. In this work, we have developed a novel structural/functional connectomic approach: resting state fMRI was used to identify the functional cortical network nodes and diffusion MRI to reconstruct the fiber tracts to give a weight to internodal subcortical connections. Then, local and global efficiency were determined for different networks, exploring specific alterations of integration and segregation patterns in AD and MCI patients compared to healthy controls (HC. In the default mode network (DMN, that was the most affected, axonal loss and reduced axonal integrity appeared to compromise both local and global efficiency along posterior-anterior connections. In the basal ganglia network (BGN, disruption of white matter integrity implied that main alterations occurred in local microstructure. In the anterior insular network (AIN, neuronal loss probably subtended a compromised communication with the insular cortex. Cognitive performance, evaluated by neuropsychological examinations, revealed a dependency on integration and segregation of brain networks. These findings are indicative of the fact that cognitive deficits in AD could be associated not only with cortical alterations (revealed by fMRI but also with subcortical alterations (revealed by diffusion MRI that extend beyond the areas primarily damaged by neurodegeneration, towards the support of an emerging concept of AD as a

  11. Interpreting the effects of altered brain anatomical connectivity on fMRI functional connectivity: a role for computational neural modeling.

    Science.gov (United States)

    Horwitz, Barry; Hwang, Chuhern; Alstott, Jeff

    2013-01-01

    Recently, there have been a large number of studies using resting state fMRI to characterize abnormal brain connectivity in patients with a variety of neurological, psychiatric, and developmental disorders. However, interpreting what the differences in resting state fMRI functional connectivity (rsfMRI-FC) actually reflect in terms of the underlying neural pathology has proved to be elusive because of the complexity of brain anatomical connectivity. The same is the case for task-based fMRI studies. In the last few years, several groups have used large-scale neural modeling to help provide some insight into the relationship between brain anatomical connectivity and the corresponding patterns of fMRI-FC. In this paper we review several efforts at using large-scale neural modeling to investigate the relationship between structural connectivity and functional/effective connectivity to determine how alterations in structural connectivity are manifested in altered patterns of functional/effective connectivity. Because the alterations made in the anatomical connectivity between specific brain regions in the model are known in detail, one can use the results of these simulations to determine the corresponding alterations in rsfMRI-FC. Many of these simulation studies found that structural connectivity changes do not necessarily result in matching changes in functional/effective connectivity in the areas of structural modification. Often, it was observed that increases in functional/effective connectivity in the altered brain did not necessarily correspond to increases in the strength of the anatomical connection weights. Note that increases in rsfMRI-FC in patients have been interpreted in some cases as resulting from neural plasticity. These results suggest that this interpretation can be mistaken. The relevance of these simulation findings to the use of functional/effective fMRI connectivity as biomarkers for brain disorders is also discussed.

  12. Altered sensorimotor activation patterns in idiopathic dystonia-an activation likelihood estimation meta-analysis of functional brain imaging studies

    DEFF Research Database (Denmark)

    Løkkegaard, Annemette; Herz, Damian M; Haagensen, Brian N;

    2016-01-01

    . Further, study size was usually small including different types of dystonia. Here we performed an activation likelihood estimation (ALE) meta-analysis of functional neuroimaging studies in patients with primary dystonia to test for convergence of dystonia-related alterations in task-related activity....... Hum Brain Mapp 37:547-557, 2016. © 2015 Wiley Periodicals, Inc....

  13. Early endocrine alterations reflect prolonged stress and relate to one year functional outcome in patients with severe brain injury

    DEFF Research Database (Denmark)

    Marina, Djordje; Klose, Marianne; Nordenbo, Annette

    2015-01-01

    OBJECTIVE: Severe brain injury poses a risk of developing acute and chronic hypopituitarism. Pituitary hormone alterations developed in the early recovery phase after brain injury may have implications for long-term functional recovery. The objective was to assess the pattern and prevalence...

  14. Alteration of plasma glutamate and glutamine levels in children with high-functioning autism.

    Directory of Open Access Journals (Sweden)

    Chie Shimmura

    Full Text Available BACKGROUND: It has recently been hypothesized that hyperglutamatergia in the brain is involved in the pathophysiology of autism. However, there is no conclusive evidence of the validity of this hypothesis. As peripheral glutamate/glutamine levels have been reported to be correlated with those of the central nervous system, the authors examined whether the levels of 25 amino acids, including glutamate and glutamine, in the platelet-poor plasma of drug-naïve, male children with high-functioning autism (HFA would be altered compared with those of normal controls. METHODOLOGY/PRINCIPAL FINDINGS: Plasma levels of 25 amino acids in male children (N = 23 with HFA and normally developed healthy male controls (N = 22 were determined using high-performance liquid chromatography. Multiple testing was allowed for in the analyses. Compared with the normal control group, the HFA group had higher levels of plasma glutamate and lower levels of plasma glutamine. No significant group difference was found in the remaining 23 amino acids. The effect size (Cohen's d for glutamate and glutamine was large: 1.13 and 1.36, respectively. Using discriminant analysis with logistic regression, the two values of plasma glutamate and glutamine were shown to well-differentiate the HFA group from the control group; the rate of correct classification was 91%. CONCLUSIONS/SIGNIFICANCE: The present study suggests that plasma glutamate and glutamine levels can serve as a diagnostic tool for the early detection of autism, especially normal IQ autism. These findings indicate that glutamatergic abnormalities in the brain may be associated with the pathobiology of autism.

  15. Blood gene expression profiles suggest altered immune function associated with symptoms of generalized anxiety disorder.

    Science.gov (United States)

    Wingo, Aliza P; Gibson, Greg

    2015-01-01

    Prospective epidemiological studies found that generalized anxiety disorder (GAD) can impair immune function and increase risk for cardiovascular disease or events. Mechanisms underlying the physiological reverberations of anxiety, however, are still elusive. Hence, we aimed to investigate molecular processes mediating effects of anxiety on physical health using blood gene expression profiles of 336 community participants (157 anxious and 179 control). We examined genome-wide differential gene expression in anxiety, as well as associations between nine major modules of co-regulated transcripts in blood gene expression and anxiety. No significant differential expression was observed in women, but 631 genes were differentially expressed between anxious and control men at the false discovery rate of 0.1 after controlling for age, body mass index, race, and batch effect. Gene set enrichment analysis (GSEA) revealed that genes with altered expression levels in anxious men were involved in response of various immune cells to vaccination and to acute viral and bacterial infection, and in a metabolic network affecting traits of metabolic syndrome. Further, we found one set of 260 co-regulated genes to be significantly associated with anxiety in men after controlling for the relevant covariates, and demonstrate its equivalence to a component of the stress-related conserved transcriptional response to adversity profile. Taken together, our results suggest potential molecular pathways that can explain negative effects of GAD observed in epidemiological studies. Remarkably, even mild anxiety, which most of our participants had, was associated with observable changes in immune-related gene expression levels. Our findings generate hypotheses and provide incremental insights into molecular mechanisms mediating negative physiological effects of GAD.

  16. Alterations in perivascular sympathetic and nitrergic innervation function induced by late pregnancy in rat mesenteric arteries.

    Directory of Open Access Journals (Sweden)

    Esther Sastre

    Full Text Available We investigated whether pregnancy was associated with changed function in components of perivascular mesenteric innervation and the mechanism/s involved.We used superior mesenteric arteries from female Sprague-Dawley rats divided into two groups: control rats (in oestrous phase and pregnant rats (20 days of pregnancy. Modifications in the vasoconstrictor response to electrical field stimulation (EFS were analysed in the presence/absence of phentolamine (alpha-adrenoceptor antagonist or L-NAME (nitric oxide synthase-NOS- non-specific inhibitor. Vasomotor responses to noradrenaline (NA, and to NO donor DEA-NO were studied, NA and NO release measured and neuronal NOS (nNOS expression/activation analysed.EFS induced a lower frequency-dependent contraction in pregnant than in control rats. Phentolamine decreased EFS-induced vasoconstriction in segments from both experimental groups, but to a greater extent in control rats. EFS-induced vasoconstriction was increased by L-NAME in arteries from both experimental groups. This increase was greater in segments from pregnant rats. Pregnancy decreased NA release while increasing NO release. nNOS expression was not modified but nNOS activation was increased by pregnancy. Pregnancy decreased NA-induced vasoconstriction response and did not modify DEA-NO-induced vasodilation response.Neural control of mesenteric vasomotor tone was altered by pregnancy. Diminished sympathetic and enhanced nitrergic components both contributed to the decreased vasoconstriction response to EFS during pregnancy. All these changes indicate the selective participation of sympathetic and nitrergic innervations in vascular adaptations produced during pregnancy.

  17. Altered fibrin clot structure/function in patients with antiphospholipid syndrome: association with thrombotic manifestation.

    Science.gov (United States)

    Celińska-Lowenhoff, M; Iwaniec, T; Padjas, A; Musiał, J; Undas, A

    2014-08-01

    We tested the hypothesis that plasma fibrin clot structure/function is unfavourably altered in patients with antiphospholipid syndrome (APS). Ex vivo plasma clot permeability, turbidity and susceptibility to lysis were determined in 126 consecutive patients with APS enrolled five months or more since thrombotic event vs 105 controls. Patients with both primary and secondary APS were characterised by 11% lower clot permeability (p<0.001), 4.8% shorter lag phase (p<0.001), 10% longer clot lysis time (p<0.001), and 4.7% higher maximum level of D-dimer released from clots (p=0.02) as compared to the controls. Scanning electron microscopy images confirmed denser fibrin networks composed of thinner fibres in APS. Clots from patients with "triple-antibody positivity" were formed after shorter lag phase (p=0.019) and were lysed at a slower rate (p=0.004) than in the remainder. Clots from APS patients who experienced stroke and/or myocardial infarction were 8% less permeable (p=0.01) and susceptible to lysis (10.4% longer clot lysis time [p=0.006] and 4.5% slower release of D-dimer from clots [p=0.01]) compared with those following venous thromboembolism alone. Multivariate analysis adjusted for potential confounders showed that in APS patients, lupus anticoagulant and "triple-positivity" were the independent predictors of clot permeability, while "triple-positivity" predicted lysis time. We conclude that APS is associated with prothrombotic plasma fibrin clot phenotype, with more pronounced abnormalities in arterial thrombosis. Molecular background for this novel prothrombotic mechanism in APS remains to be established.

  18. Acupuncture induces divergent alterations of functional connectivity within conventional frequency bands: evidence from MEG recordings.

    Directory of Open Access Journals (Sweden)

    Youbo You

    Full Text Available As an ancient Chinese healing modality which has gained increasing popularity in modern society, acupuncture involves stimulation with fine needles inserted into acupoints. Both traditional literature and clinical data indicated that modulation effects largely depend on specific designated acupoints. However, scientific representations of acupoint specificity remain controversial. In the present study, considering the new findings on the sustained effects of acupuncture and its time-varied temporal characteristics, we employed an electrophysiological imaging modality namely magnetoencephalography with a temporal resolution on the order of milliseconds. Taken into account the differential band-limited signal modulations induced by acupuncture, we sought to explore whether or not stimulation at Stomach Meridian 36 (ST36 and a nearby non-meridian point (NAP would evoke divergent functional connectivity alterations within delta, theta, alpha, beta and gamma bands. Whole-head scanning was performed on 28 healthy participants during an eyes-closed no-task condition both preceding and following acupuncture. Data analysis involved calculation of band-limited power (BLP followed by pair-wise BLP correlations. Further averaging was conducted to obtain local and remote connectivity. Statistical analyses revealed the increased connection degree of the left temporal cortex within delta (0.5-4 Hz, beta (13-30 Hz and gamma (30-48 Hz bands following verum acupuncture. Moreover, we not only validated the closer linkage of the left temporal cortex with the prefrontal and frontal cortices, but further pinpointed that such patterns were more extensively distributed in the ST36 group in the delta and beta bands compared to the restriction only to the delta band for NAP. Psychophysical results for significant pain threshold elevation further confirmed the analgesic effect of acupuncture at ST36. In conclusion, our findings may provide a new perspective to lend

  19. Vaccenic acid favourably alters immune function in obese JCR:LA-cp rats.

    Science.gov (United States)

    Blewett, Heather J; Gerdung, Christopher A; Ruth, Megan R; Proctor, Spencer D; Field, Catherine J

    2009-08-01

    Vaccenic acid (VA) is a ruminant-derived trans-fat and precursor of conjugated linoleic acid (CLA). The objective of the present study was to explore the effects of VA on immune function in a model of the metabolic syndrome, JCR:LA-cp rats. Lean (2:1 mix of +/cp and +/+) and obese (cp/cp) rats, aged 8 weeks, were fed a control (0% VA) or a VA diet (1.5% (w/w) VA) for 3 weeks (twenty rats per group). Splenocytes and mesenteric lymph node (MLN) immune cell phenotypes (flow cytometry), ex vivo cytokine production (ELISA) and phospholipid fatty acid concentrations were measured. Obese rats had higher proportions of splenic macrophages, total T-cells, helper T-cells (total and percentage CD25+), cytotoxic T-cells (total and percentage CD25+) and produced higher concentrations of IL-6 to concanavalin A (ConA) compared with lean rats. Obese rats had lower proportions of MLN T-cells, new T-cells (CD3+CD90+) and cytotoxic T-cells, but higher proportions of helper cells that were CD45RC+, CD25+ and CD4lo, and produced higher concentrations of IL-2, IL-10, interferon gamma and TNFalpha in response to ConA compared with lean rats. VA was higher in plasma phospholipids and both VA and CLA (cis-9, trans-11) were higher in MLN phospholipids compared with control-fed rats. Lean VA-fed rats had lower proportions of MLN and splenocyte CD45RC+ helper cells, and helper T-cells. Splenocytes from VA-fed rats produced 16-23% less IL-2, IL-10 and TNFalpha compared with controls. VA normalised production of MLN IL-2 and TNFalpha in obese rats to levels similar to those seen in lean rats. These results indicate that dietary VA favourably alters the pro-inflammatory tendency of mesenteric lymphocytes from JCR:LA-cp rats.

  20. Differential alterations in striatal acetylcholine function in rats during 12 months' continuous administration of haloperidol, sulpiride, or clozapine.

    Science.gov (United States)

    Rupniak, N M; Briggs, R S; Petersen, M M; Mann, S; Reavill, C; Jenner, P; Marsden, C D

    1986-01-01

    Rats were treated continuously for 12 months with therapeutically equivalent doses of either haloperidol (1.4-1.6 mg/kg/day), sulpiride (102-109 mg/kg/day), or clozapine (24-27 mg/kg/day). After treatment for 3 and 12 months with haloperidol or clozapine but not sulpiride, striatal acetylcholine levels were increased. Striatal choline acetyltransferase activity was not altered by any drug treatment. Vmax for striatal acetylcholinesterase activity during the course of 12 months' treatment with haloperidol or clozapine, but not with sulpiride, tended to increase; Km was not altered by any drug treatment. Bmax for specific striatal [3H]quinuclidinyl benzilate binding was not altered by haloperidol or sulpiride treatment but was transiently elevated after 6 months of clozapine treatment, thereafter returning to control levels. Kd was not altered by any drug treatment. These findings indicate that alterations in striatal acetylcholine content caused by chronic treatment with some but not all neuroleptics are due to changes in cholinergic neuronal activity rather than neurotransmitter synthesis or destruction. The effects of haloperidol but not those of clozapine may be related to the emergence of functional striatal dopamine receptor supersensitivity. Since haloperidol (which is associated with a high prevalence of tardive dyskinesias) but not clozapine (which is not) had similar effects on striatal cholinergic function, the latter may not be related to the emergence of tardive dyskinesias during chronic therapy.

  1. Natural reward experience alters AMPA and NMDA receptor distribution and function in the nucleus accumbens.

    Directory of Open Access Journals (Sweden)

    Kyle K Pitchers

    Full Text Available Natural reward and drugs of abuse converge upon the mesolimbic system which mediates motivation and reward behaviors. Drugs induce neural adaptations in this system, including transcriptional, morphological, and synaptic changes, which contribute to the development and expression of drug-related memories and addiction. Previously, it has been reported that sexual experience in male rats, a natural reward behavior, induces similar neuroplasticity in the mesolimbic system and affects natural reward and drug-related behavior. The current study determined whether sexual experience causes long-lasting changes in mating, or ionotropic glutamate receptor trafficking or function in the nucleus accumbens (NAc, following 3 different reward abstinence periods: 1 day, 1 week, or 1 month after final mating session. Male Sprague Dawley rats mated during 5 consecutive days (sexual experience or remained sexually naïve to serve as controls. Sexually experienced males displayed facilitation of initiation and performance of mating at each time point. Next, intracellular and membrane surface expression of N-methyl-D-aspartate (NMDA: NR1 subunit and α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA: GluA1, GluA2 subunits receptors in the NAc was determined using a bis(sulfosuccinimidylsuberate (BS(3 protein cross-linking assay followed by Western Blot analysis. NR1 expression was increased at 1 day abstinence both at surface and intracellular, but decreased at surface at 1 week of abstinence. GluA2 was increased intracellularly at 1 week and increased at the surface after 1 month of abstinence. Finally, whole-cell patch clamp electrophysiological recordings determined reduced AMPA/NMDA ratio of synaptic currents in NAc shell neurons following stimulation of cortical afferents in sexually experienced males after all reward abstinence periods. Together, these data show that sexual experience causes long-term alterations in glutamate receptor expression and

  2. Deterministic Differential Properties of the Compression Function of BMW

    DEFF Research Database (Denmark)

    Guo, Jian; Thomsen, Søren Steffen

    2011-01-01

    In this paper, we give some determinstic differential properties for the compression function of SHA-3 candidate Blue Midnight Wish (tweaked version for round 2). The computational complexity is about 20 compression function calls. This applies to security parameters 0/16, 1/15, and 2/14. The eff....../14. The efficient differentials can be used to find pseudo-preimages of the compression function with marginal gain over brute force. However, none of these attacks threaten the security of the BMW hash functions....

  3. Resting-state functional connectivity bias of middle temporal gyrus and caudate with altered gray matter volume in major depression.

    Directory of Open Access Journals (Sweden)

    Chaoqiong Ma

    Full Text Available Magnetic resonance imaging (MRI studies have indicated that the structure deficits and resting-state functional connectivity (FC imbalances in cortico-limbic circuitry might underline the pathophysiology of MDD. Using structure and functional MRI, our aim is to investigate gray matter abnormalities in patients with treatment-resistant depression (TRD and treatment-responsive depression (TSD, and test whether the altered gray matter is associated with altered FC. Voxel-based morphometry was used to investigate the regions with gray matter abnormality and FC analysis was further conducted between each gray matter abnormal region and the remaining voxels in the brain. Using one-way analysis of variance, we found significant gray matter abnormalities in the right middle temporal cortex (MTG and bilateral caudate among the TRD, TSD and healthy controls. For the FC of the right MTG, we found that both the patients with TRD and TSD showed altered connectivity mainly in the default-mode network (DMN. For the FC of the right caudate, both patient groups showed altered connectivity in the frontal regions. Our results revealed the gray matter reduction of right MTG and bilateral caudate, and disrupted functional connection to widely distributed circuitry in DMN and frontal regions, respectively. These results suggest that the abnormal DMN and reward circuit activity might be biomarkers of depression trait.

  4. Physical and chemical modifications of surface properties lead to alterations in osteoblast behavior

    Science.gov (United States)

    Dorst, Kathryn Elizabeth

    Proper formation of the bone extracellular matrix (ECM), or osteoid, depends on the surface properties of pre-existing tissue and the aqueous chemical environment. Both of these factors greatly influence osteoblast migration, cytoskeletal organization, and calcium nodule production, important aspects when considering the biocompatibility of bone implants. By perturbing the physical and/or chemical micro-environment, it may be possible to elucidate effects on cellular function. To examine these factors, murine pre-osteoblasts (MC3T3-E1 subclones 4 and 24) were seeded on polydimethylsiloxane (PDMS) substrates containing "wide" micro-patterned ridges (20 mum width, 30 mum pitch, & 2 mum height), "narrow" micro-patterned ridges (2 mum width, 10 mum pitch, 2 mum height), no patterns (flat PDMS), and standard tissue culture (TC) polystyrene as a control. Zinc concentration was adjusted to mimic deficient (0.23 muM), serum-level (3.6 muM), and zinc-rich (50 muM) conditions. It was found that cells exhibited distinct anisotropic migration in serum-level zinc and zinc-deficient media on the wide PDMS patterns, however this was disrupted under zinc-rich conditions. Production of differentiation effectors, activated metalloproteinase-2 (MMP-2) and transforming growth factor - beta 1 (TGF-beta1), was increased with the addition of exogenous zinc. Early stage differentiation, via alkaline phosphatase, was modified by zinc levels on patterned polydimethylsiloxane (PDMS) surfaces, but not on flat PDMS or tissue culture polystyrene (TC). Late stage differentiation, visualized through calcium phosphate nodules, was markedly different at various zinc levels when the cells were cultured on TC substrates. This susceptibility to zinc content can lead to differences in bone mineral production on certain substrates if osteoblasts are not able to maintain and remodel bone effectively, a process vital to successful biomaterial integration.

  5. Structural-and-functional alterations in the arterial wall and clinical manifestations of nonspecific aortoarteritis.

    Science.gov (United States)

    Pokrovskiĭ, A V; Kuntsevich, G I; Zotikov, E A; Burtseva, E A; Kulbak, V A

    2009-01-01

    The authors studied structural-and-functional properties of the arterial wall, also assessing elastic properties of the common femoral artery and the brachial artery flow-dependent dilatation (FDD) index in a total of thirty-six patients presenting with nonspecific aortoarteritis (NAA). The overwhelming majority of the patients, i. e., twenty-four (89%), showed a statistically significant decrease in the FDD as compared with the control-group patients (P<0.05). We revealed a statistically reliable (P=0.0005) inverse correlation between the level of systolic arterial pressure and an increase in the rigidity index of the common femoral artery wall. Also determined was a correlation of the femoral artery wall rigidity (systolic AP equalling 140 mm Hg and higher) and the brachial artery flow-dependent dilatation index (r=-0.61). All the patients suffering from non-specific aortoarteritis were diagnosed as having a decrease in the elasticity values, accompanied by an increase in systolic arterial pressure (r=0.36; P=0.07). Comparing the level of systolic arterial pressure with the values of the distensibility coefficient and compliance coefficient revealed a weak inverse correlation (r=-0.28 and 0.21, respectively). Evaluating the impact of duration of the disease on the distensibility coefficient, compliance coefficient and the rigidity index made it possible to detect a statistically significant (P=0.0039) direct correlation between the rigidity index and the duration of non-specific aortoarteritis. To a leaser degree, the duration of the inflammatory process influenced the distensibility coefficient and compliance coefficient (r=-0.28; r=-0.30, respectively; P=0.06).

  6. Optical and morphological properties of infrared emitting functionalized silica nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Iovino, G. [Dipartimento di Fisica e Chimica, Università di Palermo, Via Archirafi 36, I-90123 Palermo (Italy); Malvindi, M.A. [Istituto Italiano di Tecnologia, Center for Bio-Molecular Nanotechnologies@Unile, Via Barsanti, Arnesano, I-73010 Lecce (Italy); Agnello, S., E-mail: simonpietro.agnello@unipa.it [Dipartimento di Fisica e Chimica, Università di Palermo, Via Archirafi 36, I-90123 Palermo (Italy); Buscarino, G.; Alessi, A. [Dipartimento di Fisica e Chimica, Università di Palermo, Via Archirafi 36, I-90123 Palermo (Italy); Pompa, P.P. [Istituto Italiano di Tecnologia, Center for Bio-Molecular Nanotechnologies@Unile, Via Barsanti, Arnesano, I-73010 Lecce (Italy); Gelardi, F.M. [Dipartimento di Fisica e Chimica, Università di Palermo, Via Archirafi 36, I-90123 Palermo (Italy)

    2013-11-01

    The loading process of functionalized silica nanoparticles was investigated in order to obtain nanoparticles having functional groups on their surface and Near-Infrared (NIR) emission properties. The NIR emission induced by O{sub 2} loading was studied in silica nanoparticles, produced by pyrogenic and microemulsion methods, with size ranging from 20 to 120 nm. Loading was carried out by thermal treatments in O{sub 2} atmosphere up to 400 °C and 90 bar. The effects of the thermal treatments on the NIR emission and on the structural properties were studied by luminescence and Raman techniques, whereas the morphological features were investigated by Transmission Electron Microscopy and Atomic Force Microscopy. Our data show that silica nanoparticles produced by pyrogenic technique can be loaded with O{sub 2} at lower temperature than the ones obtained by microemulsion and have a higher luminescence intensity due to the internal porosity of the latter. The treatments do not affect the nanosize of the microemulsion particles and provide NIR emitting probes of selected size. Post-processing surface functionalization of the pyrogenic nanoparticles does not affect their emission properties and provides high efficiency NIR emitters with functionalized surface. - Highlights: • Pyrogenic and microemulsion silica nanoparticles with near infrared emission. • Functionalization of nanoparticles does not change the NIR emission. • Porosity limits the emission properties of nanoparticles.

  7. The Relation between Fructose-Induced Metabolic Syndrome and Altered Renal Haemodynamic and Excretory Function in the Rat

    Directory of Open Access Journals (Sweden)

    Mohammed H. Abdulla

    2011-01-01

    Full Text Available This paper explores the possible relationships between dietary fructose and altered neurohumoral regulation of renal haemodynamic and excretory function in this model of metabolic syndrome. Fructose consumption induces hyperinsulinemia, hypertriglyceridaemia, insulin resistance, and hypertension. The pathogenesis of fructose-induced hypertension is dubious and involves numerous pathways acting both singly and together. In addition, hyperinsulinemia and hypertension contribute significantly to progressive renal disease in fructose-fed rats. Moreover, increased activity of the renin-angiotensin and sympathetic nervous systems leading to downregulation of receptors may be responsible for the blunted vascular sensitivity to angiotensin II and catecholamines, respectively. Various approaches have been suggested to prevent the development of fructose-induced hypertension and/or metabolic alteration. In this paper, we address the role played by the renin-angiotensin and sympathetic nervous systems in the haemodynamic alterations that occur due to prolonged consumption of fructose.

  8. Altered functional connectivity of the dorsolateral prefrontal cortex in first-episode patients with major depressive disorder

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Ting, E-mail: yeting@ihep.ac.cn [Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, PO Box 918, Yu-Quan St, Shijingshan District, Beijing 100049 (China); Graduate School of Chinese Academy of Sciences, PO Box 918, Yu-Quan St, Shijingshan District, Beijing 100049 (China); Peng, Jing, E-mail: ppengjjing@sina.com.cn [Department of Radiology, Xuanwu Hospital of Capital Medical University, No. 45, Chang-Chun St, Xuanwu District, Beijing 100053 (China); Nie, Binbin, E-mail: niebb@ihep.ac.cn [Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, PO Box 918, Yu-Quan St, Shijingshan District, Beijing 100049 (China); Gao, Juan, E-mail: gaojuan@ihep.ac.cn [Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, PO Box 918, Yu-Quan St, Shijingshan District, Beijing 100049 (China); Graduate School of Chinese Academy of Sciences, PO Box 918, Yu-Quan St, Shijingshan District, Beijing 100049 (China); Liu, Jiangtao, E-mail: Liujiangtao813@sina.com [Department of Radiology, Xuanwu Hospital of Capital Medical University, No. 45, Chang-Chun St, Xuanwu District, Beijing 100053 (China); Li, Yang, E-mail: Liyang2007428@hotmail.com [Department of Psychiatry, Anding Hospital of Capital Medical University, No. 5, An Kang Hutong, Deshengmen wai, Xicheng District, Beijing 100088 (China); Wang, Gang, E-mail: gangwang@gmail.com [Department of Psychiatry, Anding Hospital of Capital Medical University, No. 5, An Kang Hutong, Deshengmen wai, Xicheng District, Beijing 100088 (China); Ma, Xin, E-mail: lijianshe@medmail.com.cn [Department of Psychiatry, Anding Hospital of Capital Medical University, No. 5, An Kang Hutong, Deshengmen wai, Xicheng District, Beijing 100088 (China); Li, Kuncheng [Department of Radiology, Xuanwu Hospital of Capital Medical University, No. 45, Chang-Chun St, Xuanwu District, Beijing 100053 (China); and others

    2012-12-15

    Background: The aim of this study was to investigate resting-state functional connectivity alteration of the right dorsolateral prefrontal cortex (DLPFC) in patients with first-episode major depressive disorder (MDD). Methods: Twenty-two first-episode MDD patients and thirty age-, gender- and education-matched healthy control subjects were enrolled. Rest state functional magnetic resonance images and structure magnetic resonance images were scanned. The functional connectivity analysis was done based on the result of voxel-based morphometry (VBM). And the right DLPFC was chosen as the seed region of interests (ROI), as its gray matter density (GMD) decreased in the MDD patients compared with controls and its GMD values were negative correlation with the Hamilton Depression Rating Scale (HDRS) scores. Results: Compared to healthy controls, the MDD patients showed increased functional connectivity with right the DLPFC in the left dorsal anterior cingulate cortex (ACC), left parahippocampal gyrus (PHG), thalamus and precentral gyrus. In contrast, there were decreased functional connectivity between the right DLPFC and right parietal lobe. Conclusions: By applying the VBM results to the functional connectivity analysis, the study suggested that abnormality of GMD in right DLPFC might be related to the functional connectivity alteration in the pathophysiology of MDD, which might be useful in further characterizing structure–function relations in this disorder.

  9. Dietary isoflavones alter regulatory behaviors, metabolic hormones and neuroendocrine function in Long-Evans male rats

    Directory of Open Access Journals (Sweden)

    Bu Lihong

    2004-12-01

    protein (UCP-1 mRNA levels in brown adipose tissue (BAT were seen in Phyto-600 fed males. However, decreased core body temperature was recorded in these same animals compared to Phyto-free fed animals. Conclusions This study demonstrates that consumption of a soy-based (isoflavone-rich diet, significantly alters several parameters involved in maintaining body homeostatic balance, energy expenditure, feeding behavior, hormonal, metabolic and neuroendocrine function in male rats.

  10. Mineralogy and thermodynamic properties of magnesium phyllosilicates formed during the alteration of a simplified nuclear glass

    Science.gov (United States)

    Debure, Mathieu; De Windt, Laurent; Frugier, Pierre; Gin, Stéphane; Vieillard, Philippe

    2016-07-01

    The precipitation of crystallized magnesium phyllosilicates generally sustains the alteration rate of nuclear waste containment glass. However, glass alteration slows down to a residual rate as soon as Mg disappears from the solution. The identification of the phyllosilicates formed is therefore crucial for modeling the long-term behavior of nuclear glass. This study deals with batch alteration of the simplified nuclear glass ISG in presence of magnesium, and the characterization of the secondary phases. Morphological, chemical and structural analyses (MET, EDX, XRD) were performed to determine the nature and structure of the precipitated phases identified as trioctahedral smectites. Analyses conducted on the secondary phases proved the presence of Al, Na and Ca in the Mg-phyllosilicate phases. Such elements had been suspected but never quantitatively measured. The experimental results were then used to determine the thermodynamic solubility constants for each precipitated secondary phase at various temperatures. The calculated values were consistent with those available for sodium and magnesium saponites in the existing thermodynamic databases.

  11. Properties of graphene inks stabilized by different functional groups

    Energy Technology Data Exchange (ETDEWEB)

    Wei Di; Li Hongwei; Bower, Chris; Andrew, Piers; Ryhaenen, Tapani [Nokia Research Centre, Broers Building, 21 JJ Thomson Avenue, Cambridge CB3 0FA (United Kingdom); Han Dongxue; Zhang Qixian; Niu Li; Yang Huafeng, E-mail: di.wei@nokia.com, E-mail: lniu@ciac.jl.cn [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun City 130022, Jilin Province (China)

    2011-06-17

    Different graphene inks have been synthesized by chemical methods. These uniform dispersions were stabilized by various functional groups such as room temperature ionic liquid, polyaniline, polyelectrolyte (poly[2,5-bis(3-sulfonatopropoxy)-1,4-ethynylphenylene-alt-1, 4-ethynylphenylene] sodium salt) and poly(styrenesulfonate) (PSS). The dispersions can be easily cast into high-quality, free-standing films but with very different physiochemical properties such as surface tension and adhesion. SEM and AFM methods have been applied to have a detailed study of the properties of the inks. It is found that graphenes modified by p-type polyaniline show the highest surface tension. Diverse surface adhesive properties to the substrate are also found with various functional groups. The different viscoelasticities of graphene inks were related to the microscopic structure of their coating layer and subsequently related to the configuration, chemistry and molecular dimensions of the modifying molecules to establish the property-structure relationship. Modifications of graphene inks made from chemical reduction cannot only enable cost-effective processing for printable electronics but also extend the applications into, for example, self-assembly of graphene via bottom-up nano-architecture and surface energy engineering of the graphenes. To fabricate useful devices, understanding the surface properties of graphene inks is very important. It is the first paper of this kind to study the surface tension and adhesion of graphene influenced by different functional groups.

  12. Seed treatments affect functional and antinutritional properties of amaranth flours

    NARCIS (Netherlands)

    Gamel, T.H.; Linssen, J.P.H.; Mesallam, A.S.; Damir, A.A.; Shekib, L.A.

    2006-01-01

    The effects of seed treatments, including cooking, popping germination and flour air classification, on the functional properties and antinutritional factors of Amaranthus caudatus and Amaranthus cruentus seeds were studied. Thermal treatments increased the water absorption with a maximum value of 5

  13. Topographical and Functional Properties of Precursors to Severe Problem Behavior

    Science.gov (United States)

    Fahmie, Tara A.; Iwata, Brian A.

    2011-01-01

    A literature search identified 17 articles reporting data on 34 subjects who engaged in precursors to severe problem behavior, which we examined to identify topographical and functional characteristics. Unintelligible vocalization was the most common precursor to aggression (27%) and property destruction (29%), whereas self- or nondirected…

  14. Further properties of the zeros of Bessel functions

    Directory of Open Access Journals (Sweden)

    Carla Giordano

    1987-11-01

    Full Text Available New monotonicity and convexity properties for the zeros cνk  (k=1,2,... of the Bessel functions are proved. New inequalities for cνk are also given. These inequalities are useful for small values of ν.

  15. Functional and technological properties of camel milk proteins: a review

    DEFF Research Database (Denmark)

    Hailu, Yonas; Hansen, Egon Bech; Seifu, Eyassu

    2016-01-01

    This review summarises current knowledge on camel milk proteins, with focus on significant peculiarities in protein composition and molecular properties. Camel milk is traditionally consumed as a fresh or naturally fermented product. Within the last couple of years, an increasing quantity is being...... processed in dairy plants, and a number of consumer products have been marketed. A better understanding of the technological and functional properties, as required for product improvement, has been gained in the past years. Absence of the whey protein β-LG and a low proportion of к-casein cause differences...... in relation to dairy processing. In addition to the technological properties, there are also implications for human nutrition and camel milk proteins are of interest for applications in infant foods, for food preservation and in functional foods. Proposed health benefits include inhibition of the angiotensin...

  16. A Variant of GJD2, Encoding for Connexin 36, Alters the Function of Insulin Producing β-Cells.

    Directory of Open Access Journals (Sweden)

    Valentina Cigliola

    Full Text Available Signalling through gap junctions contributes to control insulin secretion and, thus, blood glucose levels. Gap junctions of the insulin-producing β-cells are made of connexin 36 (Cx36, which is encoded by the GJD2 gene. Cx36-null mice feature alterations mimicking those observed in type 2 diabetes (T2D. GJD2 is also expressed in neurons, which share a number of common features with pancreatic β-cells. Given that a synonymous exonic single nucleotide polymorphism of human Cx36 (SNP rs3743123 associates with altered function of central neurons in a subset of epileptic patients, we investigated whether this SNP also caused alterations of β-cell function. Transfection of rs3743123 cDNA in connexin-lacking HeLa cells resulted in altered formation of gap junction plaques and cell coupling, as compared to those induced by wild type (WT GJD2 cDNA. Transgenic mice expressing the very same cDNAs under an insulin promoter revealed that SNP rs3743123 expression consistently lead to a post-natal reduction of islet Cx36 levels and β-cell survival, resulting in hyperglycemia in selected lines. These changes were not observed in sex- and age-matched controls expressing WT hCx36. The variant GJD2 only marginally associated to heterogeneous populations of diabetic patients. The data document that a silent polymorphism of GJD2 is associated with altered β-cell function, presumably contributing to T2D pathogenesis.

  17. Generalization of Boolean Functions Properties to Functions Defined over GF(p

    Directory of Open Access Journals (Sweden)

    Saad Elmansori

    2012-01-01

    Full Text Available Problem statement: Traditionally, cryptographic applications designed on hardware have always tried to take advantage of the simplicity of implementation functions over GF(p, p = 2, to reduce costs and improve performance. On the contrast, functions defined over GF(p; p > 2, possess far better cryptographic properties than GF(2 functions. Approach: We generalize some of the previous results on cryptographic Boolean functions to functions defined over GF(p; p > 2. Results: We generalize Siegenthaler’s construction to functions defined over finite field. We characterize the linear structures of functions over GF(p in terms of their Walsh transform values. We then investigate the relation between the autocorrelation coefficients of functions over GF(p and their Walsh spectrum. We also derive an upper bound for the dimension of the linear space of the functions defined over GF(p. Finally, we present a method to construct a bent function from semi-bent functions. Conclusion: Functions defined over GF(p can achieve better cryptographic bounds than GF(2 functions. In this paper we gave a generalization of several of the GF(2 cryptographic properties to functions defined over GF(p, where p is an odd prime.

  18. Altered functional connectivity related to white matter changes inside the working memory network at the very early stage of MS.

    Science.gov (United States)

    Au Duong, My-Van; Audoin, Bertrand; Boulanouar, Kader; Ibarrola, Daniella; Malikova, Irina; Confort-Gouny, Sylrane; Celsis, Pierre; Pelletier, Jean; Cozzone, Patrick J; Ranjeva, Jean-Philippe

    2005-10-01

    Functional magnetic resonance imaging (fMRI) using paced auditory serial addition test (PASAT) as paradigm was used to study the functional connectivity in 18 patients at the very early stage of multiple sclerosis (MS) compared with 18 controls, to determine the existence of circuitry disturbance inside the working memory network and its relationship with white matter abnormalities assessed by conventional MRI and magnetization transfer ratio (MTR) imaging. The left BA 45/46 was selected as the seed region to compute correlation maps with other brain regions. After obtaining the correlation map for each subject, between-group comparisons were performed using random effect procedure. Compared with controls, patients did not show any greater functional connectivity between left BA 45/46 and other regions during PASAT. In contrast, decrease in functional connectivity was observed in patients between left BA 45/46 and left BA 9, right BA 3, and the anterior cingulate cortex (BA 24). In patients, no correlations were found between altered functional connectivity and clinical data. However, functional connectivity observed between left BA 45/46 and BA 24 in patients was correlated with the MTR of normal appearing white matter, and with brain T(2) lesion load. Altered functional connectivity is present inside the working memory network of patients at the very early stage of MS and is related to the extent of diffuse white matter changes.

  19. Specific functional connectivity alterations of the dorsal striatum in young people with depression

    Directory of Open Access Journals (Sweden)

    Rebecca Kerestes

    2015-01-01

    Conclusions: The results provide evidence that alterations in corticostriatal connectivity are evident at the early stages of the illness and are not a result of antidepressant treatment. Increased connectivity between the dorsal caudate, which is usually associated with cognitive processes, and the more affectively related ventrolateral prefrontal cortex may reflect a compensatory mechanism for dysfunctional cognitive-emotional processing in youth depression.

  20. Does Addition of Propolis to Glass Ionomer Cement Alter its Physicomechanical Properties? An In Vitro Study.

    Science.gov (United States)

    Subramaniam, P; Girish Babu, K L; Neeraja, G; Pillai, S

    Propolis is a natural resinous substance produced by honey bees. The antimicrobial effects of glass ionomer cement have been shown to improve with the addition of propolis; however its effect on the physicomechanical properties of the cement is not known.

  1. Seasonal variation in functional properties of microbial communities in beech forest soil.

    Science.gov (United States)

    Koranda, Marianne; Kaiser, Christina; Fuchslueger, Lucia; Kitzler, Barbara; Sessitsch, Angela; Zechmeister-Boltenstern, Sophie; Richter, Andreas

    2013-05-01

    Substrate quality and the availability of nutrients are major factors controlling microbial decomposition processes in soils. Seasonal alteration in resource availability, which is driven by plants via belowground C allocation, nutrient uptake and litter fall, also exerts effects on soil microbial community composition. Here we investigate if seasonal and experimentally induced changes in microbial community composition lead to alterations in functional properties of microbial communities and thus microbial processes. Beech forest soils characterized by three distinct microbial communities (winter and summer community, and summer community from a tree girdling plot, in which belowground carbon allocation was interrupted) were incubated with different (13)C-labeled substrates with or without inorganic N supply and analyzed for substrate use and various microbial processes. Our results clearly demonstrate that the three investigated microbial communities differed in their functional response to addition of various substrates. The winter communities revealed a higher capacity for degradation of complex C substrates (cellulose, plant cell walls) than the summer communities, indicated by enhanced cellulase activities and reduced mineralization of soil organic matter. In contrast, utilization of labile C sources (glucose) was lower in winter than in summer, demonstrating that summer and winter community were adapted to the availability of different substrates. The saprotrophic community established in girdled plots exhibited a significantly higher utilization of complex C substrates than the more plant root associated community in control plots if additional nitrogen was provided. In this study we were able to demonstrate experimentally that variation in resource availability as well as seasonality in temperate forest soils cause a seasonal variation in functional properties of soil microorganisms, which is due to shifts in community structure and physiological

  2. Mutation in the myelin proteolipid protein gene alters BK and SK channel function in the caudal medulla

    OpenAIRE

    Mayer, Catherine A.; Macklin, Wendy B.; Avishai, Nanthawan; Balan, Kannan; Wilson, Christopher G.; Miller, Martha J.

    2009-01-01

    Proteolipid protein (Plp) gene mutation in rodents causes severe CNS dysmyelination, early death, and lethal hypoxic ventilatory depression (Miller et al. 2004). To determine if Plp mutation alters neuronal function critical for control of breathing, the nucleus tractus solitarii (nTS) of four rodent strains were studied: myelin deficient rats (MD), myelin synthesis deficient (Plpmsd), and Plpnull mice, as well as shiverer (Mbpshi) mice, a myelin basic protein mutant. Current-voltage relation...

  3. Biochemical evaluation of a 108-member deglycobleomycin library: viability of a selection strategy for identifying bleomycin analogues with altered properties.

    Science.gov (United States)

    Ma, Qian; Xu, Zhidong; Schroeder, Benjamin R; Sun, Wenyue; Wei, Fang; Hashimoto, Shigeki; Konishi, Kazuhide; Leitheiser, Christopher J; Hecht, Sidney M

    2007-10-17

    The bleomycins (BLMs) are clinically used glycopeptide antitumor antibiotics that have been shown to mediate the sequence-selective oxidative damage of both DNA and RNA. Previously, we described the solid-phase synthesis of a library of 108 unique analogues of deglycoBLM A6, a congener that cleaves DNA analogously to BLM itself. Each member of the library was assayed for its ability to effect single- and double-strand nicking of duplex DNA, sequence-selective DNA cleavage, and RNA cleavage in the presence and absence of a metal ion cofactor. All of the analogues tested were found to mediate concentration-dependent plasmid DNA relaxation to some extent, and a number exhibited double-strand cleavage with an efficiency comparable to or greater than deglycoBLM A6. Further, some analogues having altered linker and metal-binding domains mediated altered sequence-selective cleavage, and a few were found to cleave a tRNA3Lys transcript both in the presence and in the absence of a metal cofactor. The results provide insights into structural elements within BLM that control DNA and RNA cleavage. The present study also permits inferences to be drawn regarding the practicality of a selection strategy for the solid-phase construction and evaluation of large libraries of BLM analogues having altered properties.

  4. Alteration of corrosion and nanomechanical properties of pulse electrodeposited Ni/SiC nanocomposite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Zarghami, V. [Department of Materials Science and Engineering, Sharif University of Technology, Azadi Street, Tehran (Iran, Islamic Republic of); Ghorbani, M., E-mail: Ghorbani@sharif.edu [Department of Materials Science and Engineering, Sharif University of Technology, Azadi Street, Tehran (Iran, Islamic Republic of); Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Azadi Street, Tehran (Iran, Islamic Republic of)

    2014-06-15

    Highlights: • Preparing Ni/SiC coatings on the Cu substrate by using of rotating disk electrode. • Optimizing of pulse current density parameters. • Optimizing of SiC content in the bath. • Investigation the effect of codeposited SiC amount on the properties of coatings. - Abstract: Nickel/silicon carbide composite electrodeposits were prepared on a rotating disk electrode (RDE), under pulse current condition. The effect of pulse parameters, current density, SiC content in the electrolyte on the codeposition of SiC were studied. Afterwards, the effect of codeposited SiC amount was investigated on electrochemical behavior and nanomechanical properties of coatings. The coatings were analyzed with Scanning Electron Microscopy (SEM), linear polarization, nanoindentation and Atomic Force Microscopy (AFM). The Ni–SiC electrocomposites, prepared at optimum conditions, exhibited improved nanomechanical properties in comparison to pure nickel electrodeposits. With increasing current density the morphology changed from flat surface to cauliflower structure. The Ni–SiC electrocomposites exhibited improved nanomechanical properties and corrosion resistances in comparison to pure nickel electrodeposits and these properties were improving with increasing codeposited SiC particles in electrocomposites.

  5. Dynamic Alterations in Microarchitecture, Mineralization and Mechanical Property of Subchondral Bone in Rat Medial Meniscal Tear Model of Osteoarthritis

    Directory of Open Access Journals (Sweden)

    De-Gang Yu

    2015-01-01

    Full Text Available Background: The properties of subchondral bone influence the integrity of articular cartilage in the pathogenesis of osteoarthritis (OA. However, the characteristics of subchondral bone alterations remain unresolved. The present study aimed to observe the dynamic alterations in the microarchitecture, mineralization, and mechanical properties of subchondral bone during the progression of OA. Methods: A medial meniscal tear (MMT operation was performed in 128 adult Sprague Dawley rats to induce OA. At 2, 4, 8, and 12 weeks following the MMT operation, cartilage degeneration was evaluated using toluidine blue O staining, whereas changes in the microarchitecture indices and tissue mineral density (TMD, mineral-to-collagen ratio, and intrinsic mechanical properties of subchondral bone plates (BPs and trabecular bones (Tbs were measured using micro-computed tomography scanning, confocal Raman microspectroscopy and nanoindentation testing, respectively. Results: Cartilage degeneration occurred and worsened progressively from 2 to 12 weeks after OA induction. Microarchitecture analysis revealed that the subchondral bone shifted from bone resorption early (reduced trabecular BV/TV, trabecular number, connectivity density and trabecular thickness [Tb.Th], and increased trabecular spacing (Tb.Sp at 2 and 4 weeks to bone accretion late (increased BV/TV, Tb.Th and thickness of subchondral bone plate, and reduced Tb.Sp at 8 and 12 weeks. The TMD of both the BP and Tb displayed no significant changes at 2 and 4 weeks but decreased at 8 and 12 weeks. The mineral-to-collagen ratio showed a significant decrease from 4 weeks for the Tb and from 8 weeks for the BP after OA induction. Both the elastic modulus and hardness of the Tb showed a significant decrease from 4 weeks after OA induction. The BP showed a significant decrease in its elastic modulus from 8 weeks and its hardness from 4 weeks. Conclusion: The microarchitecture, mineralization and mechanical

  6. Structural properties of prokaryotic promoter regions correlate with functional features.

    Directory of Open Access Journals (Sweden)

    Pieter Meysman

    Full Text Available The structural properties of the DNA molecule are known to play a critical role in transcription. In this paper, the structural profiles of promoter regions were studied within the context of their diversity and their function for eleven prokaryotic species; Escherichia coli, Klebsiella pneumoniae, Salmonella Typhimurium, Pseudomonas auroginosa, Geobacter sulfurreducens Helicobacter pylori, Chlamydophila pneumoniae, Synechocystis sp., Synechoccocus elongates, Bacillus anthracis, and the archaea Sulfolobus solfataricus. The main anchor point for these promoter regions were transcription start sites identified through high-throughput experiments or collected within large curated databases. Prokaryotic promoter regions were found to be less stable and less flexible than the genomic mean across all studied species. However, direct comparison between species revealed differences in their structural profiles that can not solely be explained by the difference in genomic GC content. In addition, comparison with functional data revealed that there are patterns in the promoter structural profiles that can be linked to specific functional loci, such as sigma factor regulation or transcription factor binding. Interestingly, a novel structural element clearly visible near the transcription start site was found in genes associated with essential cellular functions and growth in several species. Our analyses reveals the great diversity in promoter structural profiles both between and within prokaryotic species. We observed relationships between structural diversity and functional features that are interesting prospects for further research to yet uncharacterized functional loci defined by DNA structural properties.

  7. Properties of Water Blown Rigid Polyurethane Foams with Different Functionality

    Institute of Scientific and Technical Information of China (English)

    LI Xiaobin; CAO Hongbin; ZHANG Yi

    2008-01-01

    Water blown rigid polyurethane foams with different functionality were prepared.The physical properties of rigid foams were measured with rotational viscometer(NDJ-1),universal testing machine(lnstron3365),scanning electron microscope(SEM)and differential scanning calorimeter(DSC).The results show that the viscosity of polyether polyol increases exponentially from 62 mPa s to 6 000 mPa s with theincrease of functionality from 2 to 5.6,respectively.The overall density of foam increases slightly from 31.7kg/m3 to 37.4 kg/m3 with increasing functionality while core density exhibited little difference.Compressive strength of foam shows the similar behavior with density except for 2-functional sample.At the same time,dimensional stability becomes better with increasing functionality except for 5.6-functional foam that has worse stability than 4.8-functional foam.From the SEM results,the functionality is not an important factor in determining distribution of cell size of foam.According to the results of thermal analysis,the glass transition temperature(T)shifts to a higher temperature from 128.9℃ to 166.3℃ for the 2 to 5.6 functional foam,respectively.

  8. Adhesion defective BHK cell mutant has cell surface heparan sulfate proteoglycan of altered properties

    DEFF Research Database (Denmark)

    Couchman, J R; Austria, R; Woods, A;

    1988-01-01

    In the light of accumulating data that implicate cell surface heparan sulfate proteoglycans (HSPGs) with a role in cell interactions with extracellular matrix molecules such as fibronectin, we have compared the properties of these molecules in wild-type BHK cells and an adhesion-defective ricin......-resistant mutant (RicR14). Our results showed that the mutant, unlike BHK cells, cannot form focal adhesions when adherent to planar substrates in the presence of serum. Furthermore, while both cell lines possess similar amounts of cell surface HSPG with hydrophobic properties, that of RicR14 cells had decreased...

  9. Fatigue Induced Alteration of the Superficial Strength Properties of 2024 Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    K.-D. Bouzakis; I. Mirisidis; Sp. G. Pantelakis; A.N. Chamos

    2011-01-01

    aluminum alloy 2024 T3 specimens have been subjected to constant amplitude fatigue loading at R=0.1. During fatigue, an appreciable increase of the surface hardness of the material at the meso-scale can be observed and captured by means of nanoindentations. Surface hardness increases with increasing fatigue stress amplitude and advancing number of applied fatigue cycles. Observed increase of specimen surface hardening degree during fatigue causes an evolution of superficial mechanical strength properties of the alloy. Stress-strain curves associated with the evoluting superficial mechanical properties are derived, employing a developed finite element method (FEM)-supported evaluation procedure of nanoindentation experimental results.

  10. Altered free radical metabolism in acute mountain sickness: implications for dynamic cerebral autoregulation and blood-brain barrier function

    DEFF Research Database (Denmark)

    Bailey, D M; Evans, K A; James, P E

    2008-01-01

    (2)) and following 6 h passive exposure to hypoxia (12% O(2)). Blood flow velocity in the middle cerebral artery (MCAv) and mean arterial blood pressure (MAP) were measured for determination of CA following calculation of transfer function analysis and rate of regulation (RoR). Nine subjects......We tested the hypothesis that dynamic cerebral autoregulation (CA) and blood-brain barrier (BBB) function would be compromised in acute mountain sickness (AMS) subsequent to a hypoxia-mediated alteration in systemic free radical metabolism. Eighteen male lowlanders were examined in normoxia (21% O...

  11. Altered Long- and Short-Range Functional Connectivity in Patients with Betel Quid Dependence: A Resting-State Functional MRI Study

    Directory of Open Access Journals (Sweden)

    Tao Liu

    2016-12-01

    Full Text Available Objective: Addiction is a chronic relapsing brain disease. Brain structural abnormalities may constitute an abnormal neural network that underlies the risk of drug dependence. We hypothesized that individuals with Betel Quid Dependence (BQD have functional connectivity alterations that can be described by long- and short-range functional connectivity density(FCD maps. Methods: We tested this hypothesis using functional magnetic resonance imaging (fMRI data from subjects of the Han ethnic group in Hainan, China. Here, we examined BQD individuals (n = 33 and age-, sex-, and education-matched healthy controls (HCs (n = 32 in a rs-fMRI study to observe FCD alterations associated with the severity of BQD. Results: Compared with HCs, long-range FCD was decreased in the right anterior cingulate cortex (ACC and increased in the left cerebellum posterior lobe (CPL and bilateral inferior parietal lobule (IPL in the BQD group. Short-range FCD was reduced in the right ACC and left dorsolateral prefrontal cortex (dlPFC, and increased in the left CPL. The short-range FCD alteration in the right ACC displayed a negative correlation with the Betel Quid Dependence Scale (BQDS (r=-0.432, P=0.012, and the long-range FCD alteration of left IPL showed a positive correlation with the duration of BQD(r=0.519, P=0.002 in BQD individuals. Conclusions: fMRI revealed differences in long- and short- range FCD in BQD individuals, and these alterations might be due to BQ chewing, BQ dependency, or risk factors for developing BQD.

  12. Cytomechanical properties of papaver pollen tubes are altered after self-incompatibility challenge

    NARCIS (Netherlands)

    Geitmann, A.; McConnaughey, W.; Lang-Pauluzzi, I.; Franklin-Tong, V.E.; Emons, A.M.C.

    2004-01-01

    Self-incompatibility (SI) in Papaver rhoeas triggers a ligand-mediated signal transduction cascade, resulting in the inhibition of incompatible pollen tube growth. Using a cytomechanical approach we have demonstrated that dramatic changes to the mechanical properties of incompatible pollen tubes are

  13. Induction of advanced glycation end products and alterations of the tensile properties of articular cartilage

    NARCIS (Netherlands)

    Chen, A.C.; Temple, M.M.; Ng, D.M.; Verzijl, N.; Groot, J. de; TeKoppele, J.M.; Sah, R.L.

    2002-01-01

    Objective. To determine whether increasing advanced glycation end products (AGEs) in bovine articular cartilage to levels present in aged human cartilage modulates the tensile biomechanical properties of the tissue. Methods. Adult bovine articular cartilage samples were incubated in a buffer solutio

  14. Differences in Age-Related Alterations in Muscle Contraction Properties in Rat Tongue and Hindlimb

    Science.gov (United States)

    Connor, Nadine P.; Ota, Fumikazu; Nagai, Hiromi; Russell, John A.; Leverson, Glen

    2008-01-01

    Purpose: Because of differences in muscle architecture and biomechanics, the purpose of this study was to determine whether muscle contractile properties of rat hindlimb and tongue were differentially affected by aging. Method: Deep peroneal and hypoglossal nerves were stimulated in 6 young and 7 old Fischer 344-Brown Norway rats to allow…

  15. Muscle biopsies from human muscle diseases with myopathic pathology reveal common alterations in mitochondrial function.

    Science.gov (United States)

    Sunitha, Balaraju; Gayathri, Narayanappa; Kumar, Manish; Keshava Prasad, Thottethodi Subrahmanya; Nalini, Atchayaram; Padmanabhan, Balasundaram; Srinivas Bharath, Muchukunte Mukunda

    2016-07-01

    Muscle diseases are clinically and genetically heterogeneous and manifest as dystrophic, inflammatory and myopathic pathologies, among others. Our previous study on the cardiotoxin mouse model of myodegeneration and inflammation linked muscle pathology with mitochondrial damage and oxidative stress. In this study, we investigated whether human muscle diseases display mitochondrial changes. Muscle biopsies from muscle disease patients, represented by dysferlinopathy (dysfy) (dystrophic pathology; n = 43), polymyositis (PM) (inflammatory pathology; n = 24), and distal myopathy with rimmed vacuoles (DMRV) (distal myopathy; n = 31) were analyzed. Mitochondrial damage (ragged blue and COX-deficient fibers) was revealed in dysfy, PM, and DMRV cases by enzyme histochemistry (SDH and COX-SDH), electron microscopy (vacuolation and altered cristae) and biochemical assays (significantly increased ADP/ATP ratio). Proteomic analysis of muscle mitochondria from all three muscle diseases by isobaric tag for relative and absolute quantitation labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis demonstrated down-regulation of electron transport chain (ETC) complex subunits, assembly factors and Krebs cycle enzymes. Interestingly, 80 of the under-expressed proteins were common among the three pathologies. Assay of ETC and Krebs cycle enzyme activities validated the MS data. Mitochondrial proteins from muscle pathologies also displayed higher tryptophan (Trp) oxidation and the same was corroborated in the cardiotoxin model. Molecular modeling predicted Trp oxidation to alter the local structure of mitochondrial proteins. Our data highlight mitochondrial alterations in muscle pathologies, represented by morphological changes, altered mitochondrial proteome and protein oxidation, thereby establishing the role of mitochondrial damage in human muscle diseases. We investigated whether human muscle diseases display mitochondrial changes. Muscle biopsies

  16. In vivo endoscopic tissue diagnostics based on spectroscopic absorption, scattering, and phase function properties.

    Science.gov (United States)

    Thueler, Philippe; Charvet, Igor; Bevilacqua, Frederic; St Ghislain, M; Ory, G; Marquet, Pierre; Meda, Paolo; Vermeulen, Ben; Depeursinge, Christian

    2003-07-01

    A fast spectroscopic system for superficial and local determination of the absorption and scattering properties of tissue (480 to 950 nm) is described. The probe can be used in the working channel of an endoscope. The scattering properties include the reduced scattering coefficient and a parameter of the phase function called gamma, which depends on its first two moments. The inverse problem algorithm is based on the fit of absolute reflectance measurements to cubic B-spline functions derived from the interpolation of a set of Monte Carlo simulations. The algorithm's robustness was tested with simulations altered with various amounts of noise. The method was also assessed on tissue phantoms of known optical properties. Finally, clinical measurements performed endoscopically in vivo in the stomach of human subjects are presented. The absorption and scattering properties were found to be significantly different in the antrum and in the fundus and are correlated with histopathologic observations. The method and the instrument show promise for noninvasive tissue diagnostics of various epithelia.

  17. Quantitative, functional, and biochemical alterations in the peritoneal cells of mice exposed to whole-body gamma irradiation. 1. Changes in cellular protein, adherence properties, and enzymatic activities associated with platelet-activating factor formation and inactivation, and arachidonate metabolism. Scientific report

    Energy Technology Data Exchange (ETDEWEB)

    Steel, L.K.; Hughes, H.N.; Walden, T.L.

    1988-01-01

    Changes in total number, differentials, cell protein, adherence properties, acetyltransferase and acetylhydrolase activities, prostaglandin E2 and leukotriene C4 production, as well as calcium (2+) ionophore A23187 stimulation were examined in resident peritoneal cells isolated from mice 2h to 10 days postexposure to a single dose (7,10 or 12 Gy) of gamma radiation. Radiation dose-related reductions in macrophage and lymphocyte numbers and increases in cellular protein and capacity to adhere to plastic surfaces were evident. In-vitro irradiation also elevated the activities of acetyltransferase and acetylhydrolase (catalyzing platelet-activating factor biosynthesis and inactivation, respectively) in adherent and nonadherent peritoneal cells, particularly 3-4 days postexposure. Blood plasma from irradiated animals did not reflect the increased cellular acetylhydrolase activity. Prostaglandin E2 and leukotriene C4 synthesis were elevated postexposure, suggesting increased substrate (arachidonate) availability and increased cyclooxygenase and lipoxygenase activities. Ionospheric stimulation of enzyme activities and eicosanoid release also differed in irradiated peritoneal cells. While the properties of adherence, platelet-activating factor synthesis/inactivation-associated enzyme activities, and eicosanoid production are generally characterized as those of macrophages, lymphocytes or their products may influence or contribute to the observed radiation-induced changes.

  18. Filaggrin genotype determines functional and molecular alterations in skin of patients with atopic dermatitis and ichthyosis vulgaris.

    Directory of Open Access Journals (Sweden)

    Mårten C G Winge

    Full Text Available BACKGROUND: Several common genetic and environmental disease mechanisms are important for the pathophysiology behind atopic dermatitis (AD. Filaggrin (FLG loss-of-function is of great significance for barrier impairment in AD and ichthyosis vulgaris (IV, which is commonly associated with AD. The molecular background is, however, complex and various clusters of genes are altered, including inflammatory and epidermal-differentiation genes. OBJECTIVE: The objective was to study whether the functional and molecular alterations in AD and IV skin depend directly on FLG loss-of-function, and whether FLG genotype determines the type of downstream molecular pathway affected. METHODS AND FINDINGS: Patients with AD/IV (n = 43 and controls (n = 15 were recruited from two Swedish outpatient clinics and a Swedish AD family material with known FLG genotype. They were clinically examined and their medical history recorded using a standardized questionnaire. Blood samples and punch biopsies were taken and trans-epidermal water loss (TEWL and skin pH was assessed with standard techniques. In addition to FLG genotyping, the STS gene was analyzed to exclude X-linked recessive ichthyosis (XLI. Microarrays and quantitative real-time PCR were used to compare differences in gene expression depending on FLG genotype. Several different signalling pathways were altered depending on FLG genotype in patients suffering from AD or AD/IV. Disease severity, TEWL and pH follow FLG deficiency in the skin; and the number of altered genes and pathways are correlated to FLG mRNA expression. CONCLUSIONS: We emphasize further the role of FLG in skin-barrier integrity and the complex compensatory activation of signalling pathways. This involves inflammation, epidermal differentiation, lipid metabolism, cell signalling and adhesion in response to FLG-dependent skin-barrier dysfunction.

  19. Long-term artificial sweetener acesulfame potassium treatment alters neurometabolic functions in C57BL/6J mice.

    Directory of Open Access Journals (Sweden)

    Wei-na Cong

    Full Text Available With the prevalence of obesity, artificial, non-nutritive sweeteners have been widely used as dietary supplements that provide sweet taste without excessive caloric load. In order to better understand the overall actions of artificial sweeteners, especially when they are chronically used, we investigated the peripheral and central nervous system effects of protracted exposure to a widely used artificial sweetener, acesulfame K (ACK. We found that extended ACK exposure (40 weeks in normal C57BL/6J mice demonstrated a moderate and limited influence on metabolic homeostasis, including altering fasting insulin and leptin levels, pancreatic islet size and lipid levels, without affecting insulin sensitivity and bodyweight. Interestingly, impaired cognitive memory functions (evaluated by Morris Water Maze and Novel Objective Preference tests were found in ACK-treated C57BL/6J mice, while no differences in motor function and anxiety levels were detected. The generation of an ACK-induced neurological phenotype was associated with metabolic dysregulation (glycolysis inhibition and functional ATP depletion and neurosynaptic abnormalities (dysregulation of TrkB-mediated BDNF and Akt/Erk-mediated cell growth/survival pathway in hippocampal neurons. Our data suggest that chronic use of ACK could affect cognitive functions, potentially via altering neuro-metabolic functions in male C57BL/6J mice.

  20. Lathyrism-induced alterations in collagen cross-links influence the mechanical properties of bone material without affecting the mineral

    Science.gov (United States)

    Paschalis, E.P.; Tatakis, D.N.; Robins, S.; Fratzl, P.; Manjubala, I.; Zoehrer, R.; Gamsjaeger, S.; Buchinger, B.; Roschger, A.; Phipps, R.; Boskey, A.L.; Dall'Ara, E.; Varga, P.; Zysset, P.; Klaushofer, K.; Roschger, P.

    2011-01-01

    In the present study a rat animal model of lathyrism was employed to decipher whether anatomically confined alterations in collagen cross-links are sufficient to influence the mechanical properties of whole bone. Animal experiments were performed under an ethics committee approved protocol. Sixty-four female (47 day old) rats of equivalent weights were divided into four groups (16 per group): Controls were fed a semi-synthetic diet containing 0.6% calcium and 0.6% phosphorus for 2 or 4 weeks and β-APN treated animals were fed additionally with β-aminopropionitrile (0.1% dry weight). At the end of this period the rats in the four groups were sacrificed, and L2–L6 vertebra were collected. Collagen cross-links were determined by both biochemical and spectroscopic (Fourier transform infrared imaging (FTIRI)) analyses. Mineral content and distribution (BMDD) were determined by quantitative backscattered electron imaging (qBEI), and mineral maturity/crystallinity by FTIRI techniques. Micro-CT was used to describe the architectural properties. Mechanical performance of whole bone as well as of bone matrix material was tested by vertebral compression tests and by nano-indentation, respectively. The data of the present study indicate that β-APN treatment changed whole vertebra properties compared to non-treated rats, including collagen cross-links pattern, trabecular bone volume to tissue ratio and trabecular thickness, which were all decreased (p < 0.05). Further, compression tests revealed a significant negative impact of β-APN treatment on maximal force to failure and energy to failure, while stiffness was not influenced. Bone mineral density distribution (BMDD) was not altered either. At the material level, β-APN treated rats exhibited increased Pyd/Divalent cross-link ratios in areas confined to a newly formed bone. Moreover, nano-indentation experiments showed that the E-modulus and hardness were reduced only in newly formed bone areas under the influence

  1. The Williams syndrome chromosome 7q11.23 hemideletion confers hypersocial, anxious personality coupled with altered insula structure and function.

    Science.gov (United States)

    Jabbi, Mbemba; Kippenhan, J Shane; Kohn, Philip; Marenco, Stefano; Mervis, Carolyn B; Morris, Colleen A; Meyer-Lindenberg, Andreas; Berman, Karen Faith

    2012-04-03

    Although it is widely accepted that genes can influence complex behavioral traits such as human temperament, the underlying neurogenetic mechanisms remain unclear. Williams syndrome (WS), a rare disorder caused by a hemizygous deletion on chromosome 7q11.23, including genes important for neuronal migration and maturation (LIMK1 and CLIP2), is typified by a remarkable hypersocial but anxious personality and offers a unique opportunity to investigate this open issue. Based on the documented role of the insula in mediating emotional response tendencies and personality, we used multimodal imaging to characterize this region in WS and found convergent anomalies: an overall decrease in dorsal anterior insula (AI) gray-matter volume along with locally increased volume in the right ventral AI; compromised white-matter integrity of the uncinate fasciculus connecting the insula with the amygdala and orbitofrontal cortex; altered regional cerebral blood flow in a pattern reminiscent of the observed gray-matter alterations (i.e., widespread reductions in dorsal AI accompanied by locally increased regional cerebral blood flow in the right ventral AI); and disturbed neurofunctional interactions between the AI and limbic regions. Moreover, these genetically determined alterations of AI structure and function predicted the degree to which the atypical WS personality profile was expressed in participants with the syndrome. The AI's rich anatomical connectivity, its transmodal properties, and its involvement in the behaviors affected in WS make the observed genetically determined insular circuitry perturbations and their association with WS personality a striking demonstration of the means by which neural systems can serve as the interface between genetic variability and alterations in complex behavioral traits.

  2. The angle property of positive real functions simply derived

    DEFF Research Database (Denmark)

    Jørsboe, Helge

    1973-01-01

    The angle property of positive real (rational) functionsZ(s), namely, that|arg s | geqq |arg Z(s)|in the right half of thes-plane, can be demonstrated very simply by an examination of the imaginary parts of the functionsln(s/Z(s))andln (sZ(s)), i.e.,arg s mp arg Z(s). In particular, on a contour...... enclosing the entire first quadrant,arg s mp arg Z(s)can rather easily be shown to be nonnegative. The extremum theorem of analytic functions then assures thatarg s mp arg Z(s)cannot be negative inside the first quadrant; thus the angle property is demonstrated in the first quadrant. The same result...

  3. Functionalized 2D atomic sheets with new properties

    Science.gov (United States)

    Sun, Qiang; Zhou, Jian; Wang, Qian; Jena, Puru

    2011-03-01

    Due to the unique atomic structure and novel physical and chemical properties, graphene has sparked tremendous theoretical and experimental efforts to explore other 2D atomic sheets like B-N, Al-N, and Zn-O, where the two components offer much more complexities and flexibilities in surface modifications. Using First principles calculations based on density functional theory, we have systematically studied the semi- and fully-decorated 2D sheets with H and F and Cl. We have found that the electronic structures and magnetic properties can be effectively tuned, and the system can be a direct or an indirect semiconductor or even a half-metal, and the system can be made ferromagnetic, antiferromagnetic, or magnetically degenerate depending upon how the surface is functionalized. Discussions are made for the possible device applications.

  4. Effects of ozone on functional properties of proteins.

    Science.gov (United States)

    Uzun, Hicran; Ibanoglu, Esra; Catal, Hatice; Ibanoglu, Senol

    2012-09-15

    The present study investigates whether the ozone treatment could be an alternative to improve some functional properties of proteins. Ozone treatment was applied on whey protein isolate and egg white proteins which have been extensively used in food products to improve textural, functional and sensory attributes. Ozone treatment of proteins was performed either in aqueous solutions or as gas ozonation of pure protein powders. Foam formation and foam stability of proteins were enhanced extensively. The solubility of proteins were reduced as influenced from the aqueous and gas ozonation medium. The reduction was more pronounced in egg white proteins. Ozone treatment affected emulsion activity of whey protein isolate negatively and reduced the emulsion stability.

  5. Molecular properties,functions,and potential applications of NAD kinases

    Institute of Scientific and Technical Information of China (English)

    Feng Shi; Yongfu Li; Ye Li; Xiaoyuan Wang

    2009-01-01

    NAD kinase catalyzes the phosphorylation of NAD(H)to form NADP(H),using ATP as phosphoryl donor.It is the only key enzyme leading to the de novo NADP+/NADPH biosynthesis.Coenzymes such as NAD(H)and NADP(H)are known for their important functions.Recent studies have partially demonstrated that NAD kinase plays a crucial role in the regulation of NAD(H)/NADP(H)conversion.Here,the molecular properties,physiologic functions,and potential applications of NAD kinase are discussed.

  6. Radiation processing and functional properties of soybean ( Glycine max)

    Science.gov (United States)

    Pednekar, Mrinal; Das, Amit K.; Rajalakshmi, V.; Sharma, Arun

    2010-04-01

    Effect of radiation processing (10, 20 and 30 kGy) on soybean for better utilization was studied. Radiation processing reduced the cooking time of soybean and increased the oil absorption capacity of soy flour without affecting its proximate composition. Irradiation improved the functional properties like solubility, emulsification activity and foam stability of soybean protein isolate. The value addition effect of radiation processing has been discussed for the products (soy milk, tofu and tofu fortified patties) prepared from soybean.

  7. Geometric Properties of QCD string from Willmore Functional

    CERN Document Server

    Parthasarathy, R

    2001-01-01

    The extremum of the Willmore-like functional for $m$-dimensional Riemannian surface immersed in $d$-dimensional Riemannian manifold under normal variations is studied and various cases of interest are examined. This study is used to relate the parameters of QCD string action, including the Polyakov-Kleinert extrinsic curvature action, with the geometric properties of the world sheet. The world sheet has been shown to have {\\it{negative stiffness} on the basis of geometric considerations.

  8. SOME BOUNDARY INCREASING PROPERTIES OF HARMONIC FUNCTIONS IN LIPSCHITZ DOMAIN

    Institute of Scientific and Technical Information of China (English)

    ZHANGYIPING

    1996-01-01

    The object of this paper is to study the non-tangential increasing properties of positive harmonic function u in Lipschitz domain by means of Martin representation theory, A necessary and sufficient condition of the control of growth of u near any fixed boundary point is obtained. It is shown that the non-tangential increasing degree of u near a boundary point is exactly the local degree of its representation measure with respect to the harmonic measure. Some exanlples are given.

  9. Functional and technological properties of camel milk proteins: a review.

    Science.gov (United States)

    Hailu, Yonas; Hansen, Egon Bech; Seifu, Eyassu; Eshetu, Mitiku; Ipsen, Richard; Kappeler, Stefan

    2016-11-01

    This review summarises current knowledge on camel milk proteins, with focus on significant peculiarities in protein composition and molecular properties. Camel milk is traditionally consumed as a fresh or naturally fermented product. Within the last couple of years, an increasing quantity is being processed in dairy plants, and a number of consumer products have been marketed. A better understanding of the technological and functional properties, as required for product improvement, has been gained in the past years. Absence of the whey protein β-LG and a low proportion of к-casein cause differences in relation to dairy processing. In addition to the technological properties, there are also implications for human nutrition and camel milk proteins are of interest for applications in infant foods, for food preservation and in functional foods. Proposed health benefits include inhibition of the angiotensin converting enzyme, antimicrobial and antioxidant properties as well as an antidiabetogenic effect. Detailed investigations on foaming, gelation and solubility as well as technological consequences of processing should be investigated further for the improvement of camel milk utilisation in the near future.

  10. Induction of advanced glycation end products and alterations of the tensile properties of articular cartilage

    OpenAIRE

    Chen, A C; Temple, M.M.; Ng, D.M.; Verzijl, N; de Groot, J.; TeKoppele, J.M.; Sah, R.L.

    2002-01-01

    Objective. To determine whether increasing advanced glycation end products (AGEs) in bovine articular cartilage to levels present in aged human cartilage modulates the tensile biomechanical properties of the tissue. Methods. Adult bovine articular cartilage samples were incubated in a buffer solution with ribose to induce the formation of AGEs or in a control solution. Portions of cartilage samples were assayed for biochemical indices of AGEs and tested to assess their tensile biomechanical p...

  11. Computer analysis of effects of altering jet fuel properties on refinery costs and yields

    Science.gov (United States)

    Breton, T.; Dunbar, D.

    1984-01-01

    This study was undertaken to evaluate the adequacy of future U.S. jet fuel supplies, the potential for large increases in the cost of jet fuel, and to what extent a relaxation in jet fuel properties would remedy these potential problems. The results of the study indicate that refiners should be able to meet jet fuel output requirements in all regions of the country within the current Jet A specifications during the 1990-2010 period. The results also indicate that it will be more difficult to meet Jet A specifications on the West Coast, because the feedstock quality is worse and the required jet fuel yield (jet fuel/crude refined) is higher than in the East. The results show that jet fuel production costs could be reduced by relaxing fuel properties. Potential cost savings in the East (PADDs I-IV) through property relaxation were found to be about 1.3 cents/liter (5 cents/gallon) in January 1, 1981 dollars between 1990 and 2010. However, the savings from property relaxation were all obtained within the range of current Jet A specifications, so there is no financial incentive to relax Jet A fuel specifications in the East. In the West (PADD V) the potential cost savings from lowering fuel quality were considerably greater than in the East. Cost savings from 2.7 to 3.7 cents/liter (10-14 cents/gallon) were found. In contrast to the East, on the West Coast a significant part of the savings was obtained through relaxation of the current Jet A fuel specifications.

  12. Intrinsic brain activity in altered states of consciousness: how conscious is the default mode of brain function?

    Science.gov (United States)

    Boly, M; Phillips, C; Tshibanda, L; Vanhaudenhuyse, A; Schabus, M; Dang-Vu, T T; Moonen, G; Hustinx, R; Maquet, P; Laureys, S

    2008-01-01

    Spontaneous brain activity has recently received increasing interest in the neuroimaging community. However, the value of resting-state studies to a better understanding of brain-behavior relationships has been challenged. That altered states of consciousness are a privileged way to study the relationships between spontaneous brain activity and behavior is proposed, and common resting-state brain activity features observed in various states of altered consciousness are reviewed. Early positron emission tomography studies showed that states of extremely low or high brain activity are often associated with unconsciousness. However, this relationship is not absolute, and the precise link between global brain metabolism and awareness remains yet difficult to assert. In contrast, voxel-based analyses identified a systematic impairment of associative frontoparieto-cingulate areas in altered states of consciousness, such as sleep, anesthesia, coma, vegetative state, epileptic loss of consciousness, and somnambulism. In parallel, recent functional magnetic resonance imaging studies have identified structured patterns of slow neuronal oscillations in the resting human brain. Similar coherent blood oxygen level-dependent (BOLD) systemwide patterns can also be found, in particular in the default-mode network, in several states of unconsciousness, such as coma, anesthesia, and slow-wave sleep. The latter results suggest that slow coherent spontaneous BOLD fluctuations cannot be exclusively a reflection of conscious mental activity, but may reflect default brain connectivity shaping brain areas of most likely interactions in a way that transcends levels of consciousness, and whose functional significance remains largely in the dark.

  13. Altered neurotransmitter function in CO2-exposed stickleback (Gasterosteus aculeatus): a temperate model species for ocean acidification research.

    Science.gov (United States)

    Lai, Floriana; Jutfelt, Fredrik; Nilsson, Göran E

    2015-01-01

    Studies on the consequences of ocean acidification for the marine ecosystem have revealed behavioural changes in coral reef fishes exposed to sustained near-future CO2 levels. The changes have been linked to altered function of GABAergic neurotransmitter systems, because the behavioural alterations can be reversed rapidly by treatment with the GABAA receptor antagonist gabazine. Characterization of the molecular mechanisms involved would be greatly aided if these can be examined in a well-characterized model organism with a sequenced genome. It was recently shown that CO2-induced behavioural alterations are not confined to tropical species, but also affect the three-spined stickleback, although an involvement of the GABAA receptor was not examined. Here, we show that loss of lateralization in the stickleback can be restored rapidly and completely by gabazine treatment. This points towards a worrying universality of disturbed GABAA function after high-CO2 exposure in fishes from tropical to temperate marine habitats. Importantly, the stickleback is a model species with a sequenced and annotated genome, which greatly facilitates future studies on underlying molecular mechanisms.

  14. Effects of secondary β and γ phases on the work function properties of Cu-Be alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, D.B.; Liu, C.M.; Han, T.; Liu, Y.D. [Central South University, School of Materials Science and Engineering, Changsha, Hunan (China); Xie, H.P. [Central South University, Institute of Super-microstructure and Ultrafast Process in Advanced Materials, School of Physics and Electronics, Changsha, Hunan (China)

    2015-09-15

    The work functions of Cu-2.7Be and Cu-2.0Be (wt%) alloys were measured using ultraviolet photoelectron spectroscopy, and their dependence on secondary phase characteristics (composition and distribution) was investigated. The work function properties were significantly altered when the Be content was increased from 2.0 to 2.7 wt%, which was attributed to the introduction of secondary phases (β and γ) in the alloys with higher Be content. Furthermore, the distribution of secondary phases may also have influenced the gradients of the work function curves measured by UPS. (orig.)

  15. Early manifestation of alteration in cardiac function in dystrophin deficient mdx mouse using 3D CMR tagging

    Directory of Open Access Journals (Sweden)

    Zhong Jia

    2009-10-01

    Full Text Available Abstract Background Duchenne muscular dystrophy (DMD is caused by the absence of the cytoskeletal protein, dystrophin. In DMD patients, dilated cardiomyopathy leading to heart failure may occur during adolescence. However, early cardiac dysfunction is frequently undetected due to physical inactivity and generalized debilitation. The objective of this study is to determine the time course of cardiac functional alterations in mdx mouse, a mouse model of DMD, by evaluating regional ventricular function with CMR tagging. Methods In vivo myocardial function was evaluated by 3D CMR tagging in mdx mice at early (2 months, middle (7 months and late (10 months stages of disease development. Global cardiac function, regional myocardial wall strains, and ventricular torsion were quantified. Myocardial lesions were assessed with Masson's trichrome staining. Results Global contractile indexes were similar between mdx and C57BL/6 mice in each age group. Histology analysis showed that young mdx mice were free of myocardial lesions. Interstitial fibrosis was present in 7 month mdx mice, with further development into patches or transmural lesions at 10 months of age. As a result, 10 month mdx mice showed significantly reduced regional strain and torsion. However, young mdx mice showed an unexpected increase in regional strain and torsion, while 7 month mdx mice displayed similar regional ventricular function as the controls. Conclusion Despite normal global ventricular function, CMR tagging detected a biphasic change in myocardial wall strain and torsion, with an initial increase at young age followed by progressive decrease at older ages. These results suggest that CMR tagging can provide more sensitive measures of functional alterations than global functional indexes in dystrophin-related cardiomyopathies.

  16. Functional properties of spinach (Spinacia oleracea L.) phytochemicals and bioactives.

    Science.gov (United States)

    Roberts, Joseph L; Moreau, Régis

    2016-08-10

    Overwhelming evidence indicates that diets rich in fruits and vegetables are protective against common chronic diseases, such as cancer, obesity and cardiovascular disease. Leafy green vegetables, in particular, are recognized as having substantial health-promoting activities that are attributed to the functional properties of their nutrients and non-essential chemical compounds. Spinach (Spinacia oleracea L.) is widely regarded as a functional food due to its diverse nutritional composition, which includes vitamins and minerals, and to its phytochemicals and bioactives that promote health beyond basic nutrition. Spinach-derived phytochemicals and bioactives are able to (i) scavenge reactive oxygen species and prevent macromolecular oxidative damage, (ii) modulate expression and activity of genes involved in metabolism, proliferation, inflammation, and antioxidant defence, and (iii) curb food intake by inducing secretion of satiety hormones. These biological activities contribute to the anti-cancer, anti-obesity, hypoglycemic, and hypolipidemic properties of spinach. Despite these valuable attributes, spinach consumption remains low in comparison to other leafy green vegetables. This review examines the functional properties of spinach in cell culture, animals and humans with a focus on the molecular mechanisms by which spinach-derived non-essential phytochemicals and bioactives, such as glycolipids and thylakoids, impart their health benefits.

  17. Efficient Density Functional Approximation for Electronic Properties of Conjugated Systems

    Science.gov (United States)

    Caldas, Marília J.; Pinheiro, José Maximiano, Jr.; Blum, Volker; Rinke, Patrick

    2014-03-01

    There is on-going discussion about reliable prediction of electronic properties of conjugated oligomers and polymers, such as ionization potential IP and energy gap. Several exchange-correlation (XC) functionals are being used by the density functional theory community, with different success for different properties. In this work we follow a recent proposal: a fraction α of exact exchange is added to the semi-local PBE XC aiming consistency, for a given property, with the results obtained by many-body perturbation theory within the G0W0 approximation. We focus the IP, taken as the negative of the highest occupied molecular orbital energy. We choose α from a study of the prototype family trans-acetylene, and apply this same α to a set of oligomers for which there is experimental data available (acenes, phenylenes and others). Our results indicate we can have excellent estimates, within 0,2eV mean ave. dev. from the experimental values, better than through complete EN - 1 -EN calculations from the starting PBE functional. We also obtain good estimates for the electrical gap and orbital energies close to the band edge. Work supported by FAPESP, CNPq, and CAPES, Brazil, and DAAD, Germany.

  18. Surface functional groups and redox property of modified activated carbons

    Institute of Scientific and Technical Information of China (English)

    Zhang Xianglan; Deng Shengfu; Liu Qiong; Zhang Yan; Cheng Lei

    2011-01-01

    A series of activated carbons (ACs) were prepared using HNO3, H2O2 and steam as activation agents with the aim to introduce functional groups to carbon surface in the ACs preparation process. The effects of concentration of activation agent, activation time on the surface functional groups and redox property of ACs were characterized by Temperature Program Desorption (TPD) and Cyclic Voitammetry (CV). Results showed that lactone groups of ACs activated by HNO3 increase with activation time, and the carboxyl groups increase with the concentration of HNO3. Carbonyl/quinine groups of ACs activated by H2O2 increase with the activation time and the concentration of H2O2, although the acidic groups decrease with the concentration of H2O2. The redox property reflected by CV at 0 and 0.5 V is different with any kinds of oxygen functional groups characterized by TPD, but it is consistent with the SO2 catalytic oxidization/oxidation properties indicated by TPR.

  19. Mutations that alter the transport function of the LamB protein in Escherichia coli.

    OpenAIRE

    Wandersman, C; Schwartz, M

    1982-01-01

    Some Escherichia coli K-12 lamB mutants, those producing reduced amounts of LamB protein (one-tenth the wild type amount), grow normally on dextrins but transport maltose when present at a concentration of 1 microM at about one-tenth the normal rate. lamB Dex- mutants were found as derivatives of these strains. These Dex- mutants are considerably impaired in the transport of maltose at low concentrations (below 10 microM), and they have a structurally altered LamB protein which is impaired in...

  20. Polymeric tannins significantly alter properties and in vitro digestibility of partially gelatinized intact starch granule.

    Science.gov (United States)

    Amoako, Derrick B; Awika, Joseph M

    2016-10-01

    Excess calorie intake is a growing global problem. This study investigated effect of complexing partially gelatinized starch with condensed tannins on in vitro starch digestibility. Extracts from tannin and non-tannin sorghum, and cellulose control, were reacted with normal and waxy maize starch in 30% (30E) and 50% ethanol (50E) solutions at 70°C/20min. More tannins complexed with the 30E than 50E starches (mean 6.2 vs 3.5mg/g, respectively). In the 30E treatments, tannins significantly increased crystallinity, pasting temperature, peak viscosity, and slow digesting starch (from 100 to 274mg/g) in normal, but not waxy starch, suggesting intragranular cross-linking with amylose. Tannins doubled resistant starch (RS) to approx. 300mg/g in both starches. In 50E treatments, tannins made both maize starches behave like raw potato starch (>90% RS), suggesting granule surface interactions dominated. Non-tannin treatments generally behaved similar to cellulose. Condensed tannins could be used to favorably alter starch digestion profile.

  1. Alterations in energy properties of eucalyptus wood and bark subjected to torrefaction: the potential of mass loss as a synthetic indicator.

    Science.gov (United States)

    Almeida, G; Brito, J O; Perré, P

    2010-12-01

    Torrefaction is a mild pyrolysis process (usually up to 300 degrees C) that changes the chemical and physical properties of biomass. This process is a possible pre-treatment prior to further processes (transport, grinding, combustion, gasification, etc) to generate energy or biofuels. In this study, three eucalyptus wood species and bark were subjected to different torrefaction conditions to determine the alterations in their structural and energy properties. The most severe treatment (280 degrees C, 5h) causes mass losses of more than 35%, with severe damage to anatomical structure, and an increase of about 27% in the specific energy content. Bark is more sensitive to heat than wood. Energy yields are always higher than mass yields, thereby demonstrating the benefits of torrefaction in concentrating biomass energy. The overall mass loss is proposed as a relevant parameter to synthesize the effect of torrefaction conditions (temperature and duration). Accordingly, all results are summarised by analytical expressions able to predict the energy properties as a function of the overall mass loss. These expressions are intended to be used in any optimization procedure, from production in the field to the final use.

  2. Altered function of ventral striatum during reward-based decision making in old age

    Directory of Open Access Journals (Sweden)

    Thomas Mell

    2009-10-01

    Full Text Available Normal aging is associated with a decline in different cognitive domains and local structural atrophy as well as decreases in dopamine concentration and receptor density. To date, it is largely unknown how these reductions in dopaminergic neurotransmission affect human brain regions responsible for reward-based decision making in older adults. Using a learning criterion in a probabilistic object reversal task, we found a learning stage by age interaction in the dorsolateral prefrontal cortex (dlPFC during decision making. While young adults recruited the dlPFC in an early stage of learning reward associations, older adults recruited the dlPFC when reward associations had already been learned. Furthermore, we found a reduced change in ventral striatal BOLD signal in older as compared to younger adults in response to high probability rewards. Our data are in line with behavioral evidence that older adults show altered stimulus reward learning and support the view of an altered fronto-striatal interaction during reward-based decision making in old age, which contributes to prolonged learning of reward associations.

  3. Mexican Queso Chihuahua: functional properties of aging cheese.

    Science.gov (United States)

    Olson, D W; Van Hekken, D L; Tunick, M H; Tomasula, P M; Molina-Corral, F J; Gardea, A A

    2011-09-01

    Queso Chihuahua, a semi-hard cheese manufactured from raw milk (RM) in northern Mexico, is being replaced by pasteurized milk (PM) versions because of food safety concerns and the desire for longer shelf life. In this study, the functional traits of authentic Mexican Queso Chihuahua made from RM or PM were characterized to identify sources of variation and to determine if pasteurization of the cheese milk resulted in changes to the functional properties. Two brands of RM cheese and 2 brands of PM cheese obtained in 3 seasons of the year from 4 manufacturers in Chihuahua, Mexico, were analyzed after 0, 4, 8, 12, and 16 wk of storage at 4°C. A color measurement spectrophotometer was used to collect color data before and after heating at 232°C for 5 min or 130°C for 75 min. Meltability was measured using the Schreiber Melt Test on samples heated to 232°C for 5 min. Sliceability (the force required to cut through a sample) was measured using a texture analyzer fitted with a wire cutter attachment. Proteolysis was tracked using sodium dodecyl sulfate-PAGE. Compared with PM cheeses, RM cheeses showed less browning upon heating, melted more at 232°C, and initially required a greater cutting force. With aging, cheeses increased in meltability, decreased in whiteness when measured before heating, and required less cutting force to slice. Seasonal variations in the cheesemilk had minimal or no effect on the functional properties. The differences in the functional properties can be attributed, in part, to the mixed microflora present in the RM cheeses compared with the more homogeneous microflora added during the manufacture of PM cheeses. The degree of proteolysis and subsequent integrity of the cheese matrix contribute to melt, slice, and color properties of the RM and PM cheeses. Understanding the functional properties of the authentic RM cheeses will help researchers and cheesemakers develop pasteurized versions that maintain the traditional traits desired in the

  4. Doping of TiO2 Polymorphs for Altered Optical and Photocatalytic Properties

    Directory of Open Access Journals (Sweden)

    Xiliang Nie

    2009-01-01

    Full Text Available This paper reviews recent investigations of the influence of dopants on the optical properties of TiO2 polymorphs. The common undoped polymorphs of TiO2 are discussed and compared. The results of recent doping efforts are tabulated, and discussed in the context of doping by elements of the same chemical group. Dopant effects on the band gap and photocatalytic activity are interpreted with reference to a simple qualitative picture of the TiO2 electronic structure, which is supported with first-principles calculations.

  5. Coated fatty acids alter virulence properties of Salmonella Typhimurium and decrease intestinal colonization of pigs.

    Science.gov (United States)

    Boyen, F; Haesebrouck, F; Vanparys, A; Volf, J; Mahu, M; Van Immerseel, F; Rychlik, I; Dewulf, J; Ducatelle, R; Pasmans, F

    2008-12-10

    Salmonella Typhimurium infections in pigs are a major source of human foodborne salmonellosis. To reduce the number of infected pigs, acidification of feed or drinking water is a common practice. The aim of the present study was to determine whether some frequently used short- (SCFA) and medium-chain fatty acids (MCFA) are able to alter virulence gene expression and to decrease Salmonella Typhimurium colonization and shedding in pigs using well established and controlled in vitro and in vivo assays. Minimal inhibitory concentrations (MIC) of 4 SCFA (formic acid, acetic acid, propionic acid and butyric acid) and 2 MCFA (caproic and caprylic acid) were determined using 54 porcine Salmonella Typhimurium field strains. MIC values increased at increasing pH-values and were two to eight times lower for MCFA than for SCFA. Expression of virulence gene fimA was significantly lower when bacteria were grown in LB-broth supplemented with sub-MIC concentrations of caproic or caprylic acid (2 mM). Expression of hilA and invasion in porcine intestinal epithelial cells was significantly lower when bacteria were grown in LB-broth containing sub-MIC concentrations of butyric acid or propionic acid (10 mM) and caproic or caprylic acid (2 mM). When given as feed supplement to pigs experimentally infected with Salmonella Typhimurium, coated butyric acid decreased the levels of faecal shedding and intestinal colonization, but had no influence on the colonization of tonsils, spleen and liver. Uncoated fatty acids, however, did not influence fecal shedding, intestinal or tonsillar colonization in pigs. In conclusion, supplementing feed with certain coated fatty acids, such as butyric acid, may help to reduce the Salmonella load in pigs.

  6. Alterations in the properties of neonatal thalamocortical synapses with time in in vitro slices.

    Science.gov (United States)

    Luz, Liliana L; Currie, Stephen P; Daw, Michael I

    2017-01-01

    New synapses are constantly being generated and lost in the living brain with only a subset of these being stabilized to form an enduring component of neuronal circuitry. The properties of synaptic transmission have primarily been established in a variety of in vitro neuronal preparations. It is not clear, however, if newly-formed and persistent synapses contribute to the results of these studies consistently throughout the lifespan of these preparations. In neonatal somatosensory, barrel, cortex we have previously hypothesized that a population of thalamocortical synapses displaying unusually slow kinetics represent newly-formed, default-transient synapses. This clear phenotype would provide an ideal tool to investigate if such newly formed synapses consistently contribute to synaptic transmission throughout a normal experimental protocol. We show that the proportion of synapses recorded in vitro displaying slow kinetics decreases with time after brain slice preparation. However, slow synapses persist in vitro in the presence of either minocycline, an inhibitor of microglia-mediated synapse elimination, or the TrkB agonist 7,8-dihydroxyflavone a promoter of synapse formation. These findings show that the observed properties of synaptic transmission may systematically change with time in vitro in a standard brain slice preparation.

  7. Altered age-related changes in bioenergetic properties and mitochondrial morphology in fibroblasts from sporadic amyotrophic lateral sclerosis patients.

    Science.gov (United States)

    Allen, Scott P; Duffy, Lynn M; Shaw, Pamela J; Grierson, Andrew J

    2015-10-01

    Mitochondria play a key role in aging, which is a well-established risk factor in amyotrophic lateral sclerosis (ALS). We have previously modeled metabolic dysregulation in ALS using fibroblasts isolated from sporadic ALS (SALS) and familial ALS patients. In the present study, we show that fibroblasts from SALS patients have an altered metabolic response to aging. Control fibroblasts demonstrated increased mitochondrial network complexity and spare respiratory capacity with age which was not seen in the SALS cases. SALS cases displayed an increase in uncoupled mitochondrial respiration, which was not evident in control cases. Unlike SALS cases, controls showed a decrease in glycolysis and an increase in the oxygen consumption rate/extracellular acidification rate ratio, indicating an increased reliance on mitochondrial function. Switching to a more oxidative state by removing glucose with in the culture media resulted in a loss of the mitochondrial interconnectivity and spare respiratory capacity increases observed in controls grown in glucose. Glucose removal also led to an age-independent increase in glycolysis in the SALS cases. This study is, to the best our knowledge, the first to assess the effect of aging on both mitochondrial and glycolytic function simultaneously in intact human fibroblasts and demonstrates that the SALS disease state shifts the cellular metabolic response to aging to a more glycolytic state compared with age-matched control fibroblasts. This work highlights that ALS alters the metabolic equilibrium even in peripheral tissues outside the central nervous system. Elucidating at a molecular level how this occurs and at what stage in the disease process is crucial to understanding why ALS affects cellular energy metabolism and how the disease alters the natural cellular response to aging.

  8. Sunset yellow FCF, a permitted food dye, alters functional responses of splenocytes at non-cytotoxic dose.

    Science.gov (United States)

    Yadav, Ashish; Kumar, Arvind; Tripathi, Anurag; Das, Mukul

    2013-03-13

    Sunset yellow FCF (SY), a permitted food color, is extensively used in various food preparations and quite often exceeds the permissible levels (100-200 mg/kg). Several toxicity studies on SY are reported, however immunomodulatory properties have not been explored yet. To investigate the immunotoxic properties of SY, splenocytes were isolated, cultured and subjected to mitogen stimulated proliferation assay (lipopolysaccharide, LPS or concanavalin A, Con A), mixed lymphocyte reaction (MLR) assay, immunophenotypic analysis of cell surface receptor expression and assay for cytokines release in the culture supernatants were performed in the presence of SY. Since SY did not exhibit any cytotoxicity up to 250 μg/ml, this dose was used for further studies. It was observed that SY (250 μg/ml) significantly (p<0.05) suppressed the mitogen induced proliferation of splenocytes and MLR response. Further, immunophenotypic analysis revealed that SY alters the relative expression of CD3e/CD4/CD8 in T cells and CD19 in B-cells. Consistent with the suppression of T-cell and B-cell responses and altered surface receptor expression, SY also lowered the expression of IL2, IL4, IL6, IL-17, IFN-γ and TNF-α cytokines. These results suggest that non-cytotoxic dose of SY may have immunomodulatory effects.

  9. Production of Lupinus angustifolius protein hydrolysates with improved functional properties

    Directory of Open Access Journals (Sweden)

    Millán, Francisco

    2005-06-01

    Full Text Available Protein hydrolysates wer e obtained from lupin flour and from the purified globulin α -conglutin, and their functional properties were studied. Hydrolysis with alcalase for 60 minutes yielded degrees of hydrolysis ranging from 4 % to 11 % for lupin flour, and from 4 % to 13% for α -conglutin. Protein solubility, oil absorption, foam capacity and stability, emulsifying activity, and emulsion stability of hydrolysates with 6% degree of hydrolysis were determined and compared with the properties of the original flour. The protein hydrolysates showed better functional properties than the original proteins. Most importantly, the solubility of the α -conglutin and L. angustifolius flour hydrolysates was increased by 43 % and 52 %, respectively. Thus, lupin seed protein hydrolysates have improved functional properties and could be used in the elaboration of a variety of products such as breads, cakes, and salad dressings.Se obtuvieron hidrolizados proteicos de la harina del altramuz y de la globulina α - conglutina purificada y se estudiaron sus propiedades funcionales. La hidrólisis con alcalasa durante 60 minutos produjo hidrolizados con grados de hidrólisis entre el 4 % y el 11 % para la harina y entre el 4 % y el 13 % para la α - conglutina. Se estudió en un hidrolizado con un 6 % de grado de hidrólisis la solubilidad proteica, absorción de aceite, capacidad y estabilidad espumante y actividad y estabilidad emulsificante. Los hidrolizados proteicos mostraron mejores propiedades funcionales que las proteínas originales. Más aún, la solubilidad de los hidrolizados de α - conglutina y la harina se incrementó en un 43 % y 52 % respectivamente. Así pues, hidrolizados de proteínas de semilla de lupino presentan mejores propiedades funcionales y podrían usarse en la elaboración de productos como pan, dulces, salsas o cremas.

  10. Functional and anatomical properties of human visual cortical fields.

    Science.gov (United States)

    Zhang, Shouyu; Cate, Anthony D; Herron, Timothy J; Kang, Xiaojian; Yund, E William; Bao, Shanglian; Woods, David L

    2015-04-01

    Human visual cortical fields (VCFs) vary in size and anatomical location across individual subjects. Here, we used functional magnetic resonance imaging (fMRI) with retinotopic stimulation to identify VCFs on the cortical surface. We found that aligning and averaging VCF activations across the two hemispheres provided clear delineation of multiple retinotopic fields in visual cortex. The results show that VCFs have consistent locations and extents in different subjects that provide stable and accurate landmarks for functional and anatomical mapping. Interhemispheric comparisons revealed minor differences in polar angle and eccentricity tuning in comparable VCFs in the left and right hemisphere, and somewhat greater intersubject variability in the right than left hemisphere. We then used the functional boundaries to characterize the anatomical properties of VCFs, including fractional anisotropy (FA), magnetization transfer ratio (MTR) and the ratio of T1W and T2W images and found significant anatomical differences between VCFs and between hemispheres.

  11. Lymphocyte Subset Alterations Related to Executive Function Deficits and Repetitive Stereotyped Behavior in Autism

    Science.gov (United States)

    Han, Yvonne M. Y.; Leung, Winnie Wing-man; Wong, Chun Kwok; Lam, Joseph M. K.; Cheung, Mei-Chun; Chan, Agnes S.

    2011-01-01

    Increasing evidence suggests that immunological factors are involved in the pathogenesis of autism spectrum disorders (ASD). The present study examined whether immunological abnormalities are associated with cognitive deficits in children with ASD. Eighteen high-functioning (HFA) and 19 low-functioning (LFA) children with ASD, aged 8-17 years,…

  12. The Brain as a Target for Environmental Toxicants that alter Ovarian Function.

    Science.gov (United States)

    In this review we discuss the ovarian cycle of the laboratory rat in order to familiarize the reader with the well-understood timing of the neuroendocrine events controlling ovarian function. This is followed by a discussion of the location and function of the estrogen and proges...

  13. Beneficial Effects of Tianeptine on Hippocampus-Dependent Long-Term Memory and Stress-Induced Alterations of Brain Structure and Function

    Directory of Open Access Journals (Sweden)

    Carmen Muñoz

    2010-10-01

    Full Text Available Tianeptine is a well-described antidepressant which has been shown to prevent stress from producing deleterious effects on brain structure and function. Preclinical studies have shown that tianeptine blocks stress-induced alterations of neuronal morphology and synaptic plasticity. Moreover, tianeptine prevents stress from impairing learning and memory, and, importantly, demonstrates memory-enhancing properties in the absence of stress. Recent research has indicated that tianeptine works by normalizing glutamatergic neurotransmission, a mechanism of action that may underlie its effectiveness as an antidepressant. These findings emphasize the value in focusing on the mechanisms of action of tianeptine, and specifically, the glutamatergic system, in the development of novel pharmacotherapeutic strategies in the treatment of depression.

  14. RNS60, a charge-stabilized nanostructure saline alters Xenopus Laevis oocyte biophysical membrane properties by enhancing mitochondrial ATP production.

    Science.gov (United States)

    Choi, Soonwook; Yu, Eunah; Kim, Duk-Soo; Sugimori, Mutsuyuki; Llinás, Rodolfo R

    2015-03-01

    We have examined the effects of RNS60, a 0.9% saline containing charge-stabilized oxygen nanobubble-based structures. RNS60 is generated by subjecting normal saline to Taylor-Couette-Poiseuille (TCP) flow under elevated oxygen pressure. This study, implemented in Xenopus laevis oocytes, addresses both the electrophysiological membrane properties and parallel biological processes in the cytoplasm. Intracellular recordings from defolliculated X. laevis oocytes were implemented in: (1) air oxygenated standard Ringer's solution, (2) RNS60-based Ringer's solution, (3) RNS10.3 (TCP-modified saline without excess oxygen)-based Ringer's, and (4) ONS60 (saline containing high pressure oxygen without TCP modification)-based Ringer's. RNS60-based Ringer's solution induced membrane hyperpolarization from the resting membrane potential. This effect was prevented by: (1) ouabain (a blocker of the sodium/potassium ATPase), (2) rotenone (a mitochondrial electron transfer chain inhibitor preventing usable ATP synthesis), and (3) oligomycin A (an inhibitor of ATP synthase) indicating that RNS60 effects intracellular ATP levels. Increased intracellular ATP levels following RNS60 treatment were directly demonstrated using luciferin/luciferase photon emission. These results indicate that RNS60 alters intrinsic the electrophysiological properties of the X. laevis oocyte membrane by increasing mitochondrial-based ATP synthesis. Ultrastructural analysis of the oocyte cytoplasm demonstrated increased mitochondrial length in the presence of RNS60-based Ringer's solution. It is concluded that the biological properties of RNS60 relate to its ability to optimize ATP synthesis.

  15. Altered diaphragmatic contractile properties after high airway pressure controlled mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Acute respiratory failure is the most frequent indication for the application of mechanical ventilation. 1 As commonly used in clinical settings, lung protective strategies and recruitment manoeuvres are applications of higher than normal airway pressure to open the collapsed alveoli and prevent lung atelectasis caused by minimal vital ventilation. Under those conditions, we pay more attention to the lung injury and circulatory failure, and less attention to the diaphragmatic structure and function.

  16. Alteration of membrane lipid biophysical properties and resistance of human lung adenocarcinoma A549 cells to cisplatin

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Alterations of membrane lipid biophysical properties of sensitiveA549 and resistant A549/DDP cells to the Cis-dichlorodiammine platinum (Cisplatin) were performed by measurements of fluorescence and flow cytometry approaches using fluorescence dyes of DPH, N-AS and Merocyanine 540 (MC 540) respectively. Fatty acids of membrane lipid of the two cell lines were analyzed by gas chromatography. The results indicated clearly that fluorescence polarization (P) of the DPH probe is 0.169 for the sensitive A549 cell and 0.194 for the resistant A549/DDP cells. Statistical analysis showed significant difference between the two cell lines. The polarizations of 2-AS and 7-AS which reflect the fluidity of surface and middle of lipid bilayer are 0.134 and 0.144 for the sensitive A549 cells as well as 0.171 and 0.178 for the resistant A549/DDP cells respectively, but there is no significant difference of the polarization of 12-AS between the two cell lines. This shows that altera-tions of the membrane fluidity of both cells were mainly located on the surface and middle of the lipid bilayer. In addition, the packing density of phospholipid molecules in the membrane of the two cell lines detected by MC540 probe indicated that lipid packing of A549 cell membranes was looser than that of the A549/DDP cells. And unsaturation degree of plasma membrane fatty acids of the A549/DDP cells was also lower than that of A549 cells. Taken together, it was proposed that the al-teration of membrane lipid biophysical state may be involved in the resistance of A549/DDP cells to cisplatin.

  17. Molecular weight fibrinogen variants alter gene expression and functional characteristics of human endothelial cells.

    NARCIS (Netherlands)

    Weijers, E.M.; Wijhe, M.H. van; Joosten, L.; Horrevoets, A.J.; Maat, M.P. de; Hinsbergh, V.W.H. van; Koolwijk, P.

    2010-01-01

    BACKGROUND: Fibrin is a temporary matrix that not only seals a wound, but also provides a temporary matrix structure for invading cells during wound healing. Two naturally occurring fibrinogen variants, high molecular weight (HMW) and low molecular weight (LMW) fibrinogen, display different properti

  18. Peptide-functionalized semiconductor surfaces: strong surface electronic effects from minor alterations to backbone composition.

    Science.gov (United States)

    Matmor, Maayan; Lengyel, George A; Horne, W Seth; Ashkenasy, Nurit

    2017-02-22

    The use of non-canonical amino acids is a powerful way to control protein structure. Here, we show that subtle changes to backbone composition affect the ability of a dipeptide to modify solid surface electronic properties. The extreme sensitivity of the interactions to the peptide structure suggests potential applications in improving the performance of electronic devices.

  19. Selenium-enriched durum wheat improves the nutritional profile of pasta without altering its organoleptic properties.

    Science.gov (United States)

    De Vita, Pasquale; Platani, Cristiano; Fragasso, Mariagiovanna; Ficco, Donatella Bianca Maria; Colecchia, Salvatore Antonio; Del Nobile, Matteo Alessandro; Padalino, Lucia; Di Gennaro, Spartaco; Petrozza, Angelo

    2017-01-01

    Two field experiments were conducted over three growing seasons (2006-07, 2008-09 and 2009-10) to evaluate Se-enriched pasta through foliar fertilization at various rates and timing of application on 4 durum wheat varieties. Our findings confirm the effectiveness of foliar Se fertilization to increase Se concentrations in durum wheat grain, even at high Se rates (120gSeha(-1)). Se fortification was significant across different genotypes, with greater Se accumulation in landraces ('Timilia') and obsolete varieties ('Cappelli'), with respect to modern varieties. The Se content in the grain was increased by up to 35-fold that of the untreated control. The Se concentration decreased during milling (11%), while processing and cooking of pasta did not show significant decreases. This biofortification stategy had no effects on grain quality parameters, except for reduced gluten index in the high-gluten variety PR22D89, as well as for the sensorial properties of the spaghetti.

  20. Does logging and forest conversion to oil palm agriculture alter functional diversity in a biodiversity hotspot?

    Science.gov (United States)

    Edwards, F A; Edwards, D P; Larsen, T H; Hsu, W W; Benedick, S; Chung, A; Vun Khen, C; Wilcove, D S; Hamer, K C

    2014-01-01

    Forests in Southeast Asia are rapidly being logged and converted to oil palm. These changes in land-use are known to affect species diversity but consequences for the functional diversity of species assemblages are poorly understood. Environmental filtering of species with similar traits could lead to disproportionate reductions in trait diversity in degraded habitats. Here, we focus on dung beetles, which play a key role in ecosystem processes such as nutrient recycling and seed dispersal. We use morphological and behavioural traits to calculate a variety of functional diversity measures across a gradient of disturbance from primary forest through intensively logged forest to oil palm. Logging caused significant shifts in community composition but had very little effect on functional diversity, even after a repeated timber harvest. These data provide evidence for functional redundancy of dung beetles within primary forest and emphasize the high value of logged forests as refugia for biodiversity. In contrast, conversion of forest to oil palm greatly reduced taxonomic and functional diversity, with a marked decrease in the abundance of nocturnal foragers, a higher proportion of species with small body sizes and the complete loss of telecoprid species (dung-rollers), all indicating a decrease in the functional capacity of dung beetles within plantations. These changes also highlight the vulnerability of community functioning within logged forests in the event of further environmental degradation. PMID:25821399

  1. Does logging and forest conversion to oil palm agriculture alter functional diversity in a biodiversity hotspot?

    Science.gov (United States)

    Edwards, F A; Edwards, D P; Larsen, T H; Hsu, W W; Benedick, S; Chung, A; Vun Khen, C; Wilcove, D S; Hamer, K C

    2014-04-01

    Forests in Southeast Asia are rapidly being logged and converted to oil palm. These changes in land-use are known to affect species diversity but consequences for the functional diversity of species assemblages are poorly understood. Environmental filtering of species with similar traits could lead to disproportionate reductions in trait diversity in degraded habitats. Here, we focus on dung beetles, which play a key role in ecosystem processes such as nutrient recycling and seed dispersal. We use morphological and behavioural traits to calculate a variety of functional diversity measures across a gradient of disturbance from primary forest through intensively logged forest to oil palm. Logging caused significant shifts in community composition but had very little effect on functional diversity, even after a repeated timber harvest. These data provide evidence for functional redundancy of dung beetles within primary forest and emphasize the high value of logged forests as refugia for biodiversity. In contrast, conversion of forest to oil palm greatly reduced taxonomic and functional diversity, with a marked decrease in the abundance of nocturnal foragers, a higher proportion of species with small body sizes and the complete loss of telecoprid species (dung-rollers), all indicating a decrease in the functional capacity of dung beetles within plantations. These changes also highlight the vulnerability of community functioning within logged forests in the event of further environmental degradation.

  2. Prenatal drug exposure to illicit drugs alters working memory-related brain activity and underlying network properties in adolescence.

    Science.gov (United States)

    Schweitzer, Julie B; Riggins, Tracy; Liang, Xia; Gallen, Courtney; Kurup, Pradeep K; Ross, Thomas J; Black, Maureen M; Nair, Prasanna; Salmeron, Betty Jo

    2015-01-01

    The persistence of effects of prenatal drug exposure (PDE) on brain functioning during adolescence is poorly understood. We explored neural activation to a visuospatial working memory (VSWM) versus a control task using functional magnetic resonance imaging (fMRI) in adolescents with PDE and a community comparison group (CC) of non-exposed adolescents. We applied graph theory metrics to resting state data using a network of nodes derived from the VSWM task activation map to further explore connectivity underlying WM functioning. Participants (ages 12-15 years) included 47 adolescents (27 PDE and 20 CC). All analyses controlled for potentially confounding differences in birth characteristics and postnatal environment. Significant group by task differences in brain activation emerged in the left middle frontal gyrus (BA 6) with the CC group, but not the PDE group, activating this region during VSWM. The PDE group deactivated the culmen, whereas the CC group activated it during the VSWM task. The CC group demonstrated a significant relation between reaction time and culmen activation, not present in the PDE group. The network analysis underlying VSWM performance showed that PDE group had lower global efficiency than the CC group and a trend level reduction in local efficiency. The network node corresponding to the BA 6 group by task interaction showed reduced nodal efficiency and fewer direct connections to other nodes in the network. These results suggest that adolescence reveals altered neural functioning related to response planning that may reflect less efficient network functioning in youth with PDE.

  3. Abnormal physiological properties and altered cell wall composition in Streptococcus pneumoniae grown in the presence of clavulanic acid.

    Science.gov (United States)

    Severin, A; Severina, E; Tomasz, A

    1997-01-01

    Subinhibitory concentrations of clavulanate caused premature induction of stationary-phase autolysis, sensitization to lysozyme, and reductions in the MICs of deoxycholate and penicillin for Streptococcus pneumoniae. In the range of clavulanate concentrations producing these effects, this beta-lactam compound was selectively bound to PBP 3. Cell walls isolated from pneumococci grown in the presence of clavulanate showed increased sensitivity to the hydrolytic action of purified pneumococcal autolysin in vitro. High-performance liquid chromatography analysis of the peptidoglycan isolated from the clavulanate-grown cells showed major qualitative and quantitative changes in stem peptide composition, the most striking feature of which was the accumulation of peptide species carrying intact D-alanyl-D-alanine residues at the carboxy termini. The altered biological and biochemical properties of the clavulanate-grown pneumococci appear to be the consequences of suppressed D,D-carboxypeptidase activity. PMID:9055983

  4. Current considerations concerning endodontically treated teeth: alteration of hard dental tissues and biomechanical properties following endodontic therapy.

    Science.gov (United States)

    Dimitriu, Bogdan; Vârlan, Constantin; Suciu, Ioana; Vârlan, Virginia; Bodnar, Dana

    2009-01-01

    The aim of this general article is to present an overview of the current knowledge about composition and structural changes and also about specific biomechanical alterations related to vitality loss or endodontic therapy. For a long time, these issues have been controversially approached from a clinical standpoint and are therefore still confusing for many practitioners. Vitality loss or endodontic procedures seem to induce only negligible changes in hard dental tissue moisture. Physico-chemical properties of dentin can be modified by some of the endodontic chemical products used for chemo-mechanical debridement. On the other hand, tooth biomechanical behavior is affected, since tooth strength is reduced proportionally to coronal tissue loss, due to either pre-existent carious/non-carious lesions or cavity acces preparation, besides restorative procedures. The related literature shows the lack of accepted clinical standards and consensus regarding the optimal way of approaching the specific tooth biomechanics following endodontic therapy.

  5. Breast cancer cell cyclooxygenase-2 expression alters extracellular matrix structure and function and numbers of cancer associated fibroblasts.

    Science.gov (United States)

    Krishnamachary, Balaji; Stasinopoulos, Ioannis; Kakkad, Samata; Penet, Marie-France; Jacob, Desmond; Wildes, Flonne; Mironchik, Yelena; Pathak, Arvind P; Solaiyappan, Meiyappan; Bhujwalla, Zaver M

    2017-01-31

    Cyclooxygenase-2 (COX-2) is a critically important mediator of inflammation that significantly influences tumor angiogenesis, invasion, and metastasis. We investigated the role of COX-2 expressed by triple negative breast cancer cells in altering the structure and function of the extracellular matrix (ECM). COX-2 downregulation effects on ECM structure and function were investigated using magnetic resonance imaging (MRI) and second harmonic generation (SHG) microscopy of tumors derived from triple negative MDA-MB-231 breast cancer cells, and a derived clone stably expressing a short hairpin (shRNA) molecule downregulating COX-2. MRI of albumin-GdDTPA was used to characterize macromolecular fluid transport in vivo and SHG microscopy was used to quantify collagen 1 (Col1) fiber morphology. COX-2 downregulation decreased Col1 fiber density and altered macromolecular fluid transport. Immunohistochemistry identified significantly fewer activated cancer associated fibroblasts (CAFs) in low COX-2 expressing tumors. Metastatic lung nodules established by COX-2 downregulated cells were infrequent, smaller, and contained fewer Col1 fibers.COX-2 overexpression studies were performed with tumors derived from triple negative SUM-149 breast cancer cells lentivirally transduced to overexpress COX-2. SHG microscopy identified significantly higher Col1 fiber density in COX-2 overexpressing tumors with an increase of CAFs. These data expand upon the roles of COX-2 in shaping the structure and function of the ECM in primary and metastatic tumors, and identify the potential role of COX-2 in modifying the number of CAFs in tumors that may have contributed to the altered ECM.

  6. Altered morphologies and functions of the olfactory bulb and hippocampus induced by miR-30c

    Directory of Open Access Journals (Sweden)

    Tingting eSun

    2016-05-01

    Full Text Available Adult neurogenesis is considered to contribute to a certain degree of plasticity for the brain. However, the effects of adult-born neurons on the brain are still largely unknown. Here, we specifically altered the expression of miR-30c in the subventricular zone (SVZ and dentate gyrus (DG by stereotaxic injection with their respective up-and down-regulated lentiviruses. Results showed an increased level of miR-30c enhanced adult neurogenesis by prompting cell-cycles of stem cells, whereas down-regulated miR-30c led to the opposite results. When these effects of miR-30c lasted for three months, we detected significant morphological changes in the olfactory bulb (OB and lineage alteration in the hippocampus. Tests of olfactory sensitivity and associative and spatial memory showed that a certain amount of adult-born neurons are essential for the normal functions of the OB and hippocampus, but there also exist redundant newborn neurons that do not further improve the functioning of these areas. Our study revealed the interactions between miRNA, adult neurogenesis, brain morphology and function, and this provides a novel insight into understanding the role of newborn neurons in the adult brain.

  7. Species replacement by a nonnative salmonid alters ecosystem function by reducing prey subsidies that support riparian spiders.

    Science.gov (United States)

    Benjamin, Joseph R; Fausch, Kurt D; Baxter, Colden V

    2011-10-01

    Replacement of a native species by a nonnative can have strong effects on ecosystem function, such as altering nutrient cycling or disturbance frequency. Replacements may cause shifts in ecosystem function because nonnatives establish at different biomass, or because they differ from native species in traits like foraging behavior. However, no studies have compared effects of wholesale replacement of a native by a nonnative species on subsidies that support consumers in adjacent habitats, nor quantified the magnitude of these effects. We examined whether streams invaded by nonnative brook trout (Salvelinus fontinalis) in two regions of the Rocky Mountains, USA, produced fewer emerging adult aquatic insects compared to paired streams with native cutthroat trout (Oncorhynchus clarkii), and whether riparian spiders that depend on these prey were less abundant along streams with lower total insect emergence. As predicted, emergence density was 36% lower from streams with the nonnative fish. Biomass of brook trout was higher than the cutthroat trout they replaced, but even after accounting for this difference, emergence was 24% lower from brook trout streams. More riparian spiders were counted along streams with greater total emergence across the water surface. Based on these results, we predicted that brook trout replacement would result in 6-20% fewer spiders in the two regions. When brook trout replace cutthroat trout, they reduce cross-habitat resource subsidies and alter ecosystem function in stream-riparian food webs, not only owing to increased biomass but also because traits apparently differ from native cutthroat trout.

  8. Functional and anatomic alterations in the gentamicin-damaged vestibular system in the guinea pig

    NARCIS (Netherlands)

    Oei, MLYM; Segenhout, HM; Dijk, T; Stokroos, [No Value; van der Want, TJL; Albers, FWJ

    2004-01-01

    Hypothesis: The purpose of this study was to investigate the expected functional and morphologic effect of gentamicin on the vestibular system simultaneously by measurement of vestibular evoked potentials and electron microscopic evaluation. Background: Vestibular short-latency evoked potentials to

  9. Prolonged cigarette smoke exposure alters mitochondrial structure and function in airway epithelial cells

    NARCIS (Netherlands)

    Hoffmann, Roland F.; Zarrintan, Sina; Brandenburg, Simone M.; Kol, Arjan; de Bruin, Harold G.; Jafari, Shabnam; Dijk, Freark; Kalicharan, Dharamdajal; Kelders, Marco; Gosker, Harry R.; ten Hacken, Nick H. T.; van der Want, Johannes J.; van Oosterhout, Antoon J. M.; Heijink, Irene H.

    2013-01-01

    Background: Cigarette smoking is the major risk factor for COPD, leading to chronic airway inflammation. We hypothesized that cigarette smoke induces structural and functional changes of airway epithelial mitochondria, with important implications for lung inflammation and COPD pathogenesis. Methods:

  10. Prolonged cigarette smoke exposure alters mitochondrial structure and function in airway epithelial cells

    NARCIS (Netherlands)

    Hoffmann, Roland F; Zarrintan, Sina; Brandenburg, Simone M; Kol, Arjan; de Bruin, Harold G; Jafari, Shabnam; Dijk, Freark; Kalicharan, Dharamdajal; Kelders, Marco; Gosker, Harry R; Ten Hacken, Nick Ht; van der Want, Johannes J; van Oosterhout, Antoon Jm; Heijink, Irene H

    2013-01-01

    BACKGROUND: Cigarette smoking is the major risk factor for COPD, leading to chronic airway inflammation. We hypothesized that cigarette smoke induces structural and functional changes of airway epithelial mitochondria, with important implications for lung inflammation and COPD pathogenesis. METHODS:

  11. Alteration of functional connectivity in autism spectrum disorder: effect of age and anatomical distance

    OpenAIRE

    Zhiliang Long; Xujun Duan; Dante Mantini; Huafu Chen

    2016-01-01

    Autism spectrum disorder (ASD) is associated with disruption of local- and long-range functional connectivity (FC). The direction of those changes in FC (increase or decrease), however, is inconsistent across studies. Further, age-dependent changes of distance-specific FC in ASD remain unclear. In this study, we used resting-state functional magnetic resonance imaging data from sixty-four typical controls (TC) and sixty-four patients with ASD, whom we further classified into child (18 years)....

  12. Altered resting-state functional connectivity in post-traumatic stress disorder: a perfusion MRI study

    Science.gov (United States)

    Li, Baojuan; Liu, Jian; Liu, Yang; Lu, Hong-Bing; Yin, Hong

    2013-03-01

    The majority of studies on posttraumatic stress disorder (PTSD) so far have focused on delineating patterns of activations during cognitive processes. Recently, more and more researches have started to investigate functional connectivity in PTSD subjects using BOLD-fMRI. Functional connectivity analysis has been demonstrated as a powerful approach to identify biomarkers of different brain diseases. This study aimed to detect resting-state functional connectivity abnormities in patients with PTSD using arterial spin labeling (ASL) fMRI. As a completely non-invasive technique, ASL allows quantitative estimates of cerebral blood flow (CBF). Compared with BOLD-fMRI, ASL fMRI has many advantages, including less low-frequency signal drifts, superior functional localization, etc. In the current study, ASL images were collected from 10 survivors in mining disaster with recent onset PTSD and 10 survivors without PTSD. Decreased regional CBF in the right middle temporal gyrus, lingual gyrus, and postcentral gyrus was detected in the PTSD patients. Seed-based resting-state functional connectivity analysis was performed using an area in the right middle temporal gyrus as region of interest. Compared with the non-PTSD group, the PTSD subjects demonstrated increased functional connectivity between the right middle temporal gyrus and the right superior temporal gyrus, the left middle temporal gyrus. Meanwhile, decreased functional connectivity between the right middle temporal gyrus and the right postcentral gyrus, the right superior parietal lobule was also found in the PTSD patients. This is the first study which investigated resting-state functional connectivity in PTSD using ASL images. The results may provide new insight into the neural substrates of PTSD.

  13. Amelioration of altered antioxidant status and membrane linked functions by vanadium and Trigonella in alloxan diabetic rat brains

    Indian Academy of Sciences (India)

    Mohammad Rizwan Siddiqui; Asia Taha; K Moorthy; Mohd Ejaz Hussain; S F Basir; Najma Zaheer Baquer

    2005-09-01

    Trigonella foenum graecum seed powder (TSP) and sodium orthovanadate (SOV) have been reported to have antidiabetic effects. However, SOV exerts hypoglycemic effects at relatively high doses with several toxic effects. We used low doses of vanadate in combination with TSP and evaluated their antidiabetic effects on antioxidant enzymes and membrane-linked functions in diabetic rat brains. In rats, diabetes was induced by alloxan monohydrate (15 mg/100 g body wt.) and they were treated with 2 IU insulin, 0.6 mg/ml SOV, 5% TSP and a combination of 0.2 mg/ml SOV with 5% TSP for 21 days. Blood glucose levels, activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), Na+/K+ ATPase, membrane lipid peroxidation and fluidity were determined in different fractions of whole brain after 21 days of treatment. Diabetic rats showed high blood glucose ( < 0.001), decreased activities of SOD, catalase and Na+/K+ ATPase ( < 0.01, < 0.001 and < 0.01), increased levels of GPx and MDA ( < 0.01 and < 0.001) and decreased membrane fluidity ( < 0.01). Treatment with different antidiabetic compounds restored the above-altered parameters. Combined dose of Trigonella and vanadate was found to be the most effective treatment in normalizing these alterations. Lower doses of vanadate could be used in combination with TSP to effectively counter diabetic alterations without any toxic effects.

  14. Matrix intensification alters avian functional group composition in adjacent rainforest fragments.

    Directory of Open Access Journals (Sweden)

    Justus P Deikumah

    Full Text Available Conversion of farmland land-use matrices to surface mining is an increasing threat to the habitat quality of forest remnants and their constituent biota, with consequences for ecosystem functionality. We evaluated the effects of matrix type on bird community composition and the abundance and evenness within avian functional groups in south-west Ghana. We hypothesized that surface mining near remnants may result in a shift in functional composition of avifaunal communities, potentially disrupting ecological processes within tropical forest ecosystems. Matrix intensification and proximity to the remnant edge strongly influenced the abundance of members of several functional guilds. Obligate frugivores, strict terrestrial insectivores, lower and upper strata birds, and insect gleaners were most negatively affected by adjacent mining matrices, suggesting certain ecosystem processes such as seed dispersal may be disrupted by landscape change in this region. Evenness of these functional guilds was also lower in remnants adjacent to surface mining, regardless of the distance from remnant edge, with the exception of strict terrestrial insectivores. These shifts suggest matrix intensification can influence avian functional group composition and related ecosystem-level processes in adjacent forest remnants. The management of matrix habitat quality near and within mine concessions is important for improving efforts to preserveavian biodiversity in landscapes undergoing intensification such as through increased surface mining.

  15. Altered metabolism and persistent starvation behaviors caused by reduced AMPK function in Drosophila.

    Directory of Open Access Journals (Sweden)

    Erik C Johnson

    Full Text Available Organisms must utilize multiple mechanisms to maintain energetic homeostasis in the face of limited nutrient availability. One mechanism involves activation of the heterotrimeric AMP-activated protein kinase (AMPK, a cell-autonomous sensor to energetic changes regulated by ATP to AMP ratios. We examined the phenotypic consequences of reduced AMPK function, both through RNAi knockdown of the gamma subunit (AMPKγ and through expression of a dominant negative alpha (AMPKα variant in Drosophila melanogaster. Reduced AMPK signaling leads to hypersensitivity to starvation conditions as measured by lifespan and locomotor activity. Locomotor levels in flies with reduced AMPK function were lower during unstressed conditions, but starvation-induced hyperactivity, an adaptive response to encourage foraging, was significantly higher than in wild type. Unexpectedly, total dietary intake was greater in animals with reduced AMPK function yet total triglyceride levels were lower. AMPK mutant animals displayed starvation-like lipid accumulation patterns in metabolically key liver-like cells, oenocytes, even under fed conditions, consistent with a persistent starved state. Measurements of O(2 consumption reveal that metabolic rates are greater in animals with reduced AMPK function. Lastly, rapamycin treatment tempers the starvation sensitivity and lethality associated with reduced AMPK function. Collectively, these results are consistent with models that AMPK shifts energy usage away from expenditures into a conservation mode during nutrient-limited conditions at a cellular level. The highly conserved AMPK subunits throughout the Metazoa, suggest such findings may provide significant insight for pharmaceutical strategies to manipulate AMPK function in humans.

  16. Altered pulmonary function in children with asthma associated with highway traffic near residence.

    Science.gov (United States)

    Margolis, Helene G; Mann, Jennifer K; Lurmann, Frederick W; Mortimer, Kathleen M; Balmes, John R; Hammond, S Katharine; Tager, Ira B

    2009-04-01

    Cross-sectional analyses were conducted to evaluate the effects of exposure to highway traffic on pulmonary function in Fresno, California. Traffic and spirometry data were available for 214 children (enrollment ages six to 11 years). Multiple linear regression was used to evaluate the relations between pulmonary function and traffic parameters. Heavy-duty vehicle count was used as a surrogate measure for diesel-related exposures. Pulmonary function was non-significantly associated with longer distance-to-road and non-significantly associated with higher traffic intensity. Evaluation of effect modification by FEF(25-75)/FVC (a measure of intrinsic airway size) showed that all pulmonary function measures of flow were significantly inversely related to a traffic metric that incorporates traffic intensity and roadway proximity. The results indicate that residence proximity to highway traffic is associated with lower pulmonary function among children with asthma, and smaller airway size is an important modifier of the effect of traffic exposure on pulmonary function and a marker of increased susceptibility.

  17. Dynamic Alterations in Microarchitecture, Mineralization and Mechanical Property of Subchondral Bone in Rat Medial Meniscal Tear Model of Osteoarthritis

    Institute of Scientific and Technical Information of China (English)

    De-Gang Yu; Shao-Bo Nie; Feng-Xiang Liu; Chuan-Long Wu; Bo Tian; Wen-Gang Wang; Xiao-Qing Wang

    2015-01-01

    Background:The properties of subchondral bone influence the integrity of articular cartilage in the pathogenesis of osteoarthritis (OA).However,the characteristics of subchondral bone alterations remain unresolved.The present study aimed to observe the dynamic alterations in the microarchitecture,mineralization,and mechanical properties of subchondral bone during the progression of OA.Methods:A medial meniscal tear (MMT) operation was performed in 128 adult Sprague Dawley rats to induce OA.At 2,4,8,and 12 weeks following the MMT operation,cartilage degeneration was evaluated using toluidine blue O staining,whereas changes in the microarchitecture indices and tissue mineral density (TMD),mineral-to-collagen ratio,and intrinsic mechanical properties of subchondral bone plates (BPs) and trabecular bones (Tbs) were measured using micro-computed tomography scanning,confocal Raman microspectroscopy and nanoindentation testing,respectively.Results:Cartilage degeneration occurred and worsened progressively from 2 to 12 weeks after OA induction.Microarchitecture analysis revealed that the subchondral bone shifted from bone resorption early (reduced trabecular BV/TV,trabecular number,connectivity density and trabecular thickness [Tb.Th],and increased trabecular spacing (Tb.Sp) at 2 and 4 weeks) to bone accretion late (increased BV/TV,Tb.Th and thickness of subchondral bone plate,and reduced Tb.Sp at 8 and 12 weeks).The TMD of both the BP and Tb displayed no significant changes at 2 and 4 weeks but decreased at 8 and 12 weeks.The mineral-to-collagen ratio showed a significant decrease from 4 weeks for the Tb and from 8 weeks for the BP after OA induction.Both the elastic modulus and hardness of the Tb showed a significant decrease from 4 weeks after OA induction.The BP showed a significant decrease in its elastic modulus from 8 weeks and its hardness from 4 weeks.Conclusion:The microarchitecture,mineralization and mechanical properties of subchondral bone changed in a time

  18. Alterations in cancer cell mechanical properties after fluid shear stress exposure: a micropipette aspiration study

    Directory of Open Access Journals (Sweden)

    Chivukula VK

    2015-01-01

    Full Text Available Venkat Keshav Chivukula,1 Benjamin L Krog,1,2 Jones T Nauseef,2 Michael D Henry,2 Sarah C Vigmostad1 1Department of Biomedical Engineering, 2Department of Molecular Physiology and Biophysics, Holden Comprehensive Cancer Center, University of Iowa, Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, USA Abstract: Over 90% of cancer deaths result not from primary tumor development, but from metastatic tumors that arise after cancer cells circulate to distal sites via the circulatory system. While it is known that metastasis is an inefficient process, the effect of hemodynamic parameters such as fluid shear stress (FSS on the viability and efficacy of metastasis is not well understood. Recent work has shown that select cancer cells may be able to survive and possibly even adapt to FSS in vitro. The current research seeks to characterize the effect of FSS on the mechanical properties of suspended cancer cells in vitro. Nontransformed prostate epithelial cells (PrEC LH and transformed prostate cancer cells (PC-3 were used in this study. The Young's modulus was determined using micropipette aspiration. We examined cells in suspension but not exposed to FSS (unsheared and immediately after exposure to high (6,400 dyn/cm2 and low (510 dyn/cm2 FSS. The PrEC LH cells were ~140% stiffer than the PC-3 cells not exposed to FSS. Post-FSS exposure, there was an increase of ~77% in Young's modulus after exposure to high FSS and a ~47% increase in Young's modulus after exposure to low FSS for the PC-3 cells. There was no significant change in the Young's modulus of PrEC LH cells post-FSS exposure. Our findings indicate that cancer cells adapt to FSS, with an increased Young's modulus being one of the adaptive responses, and that this adaptation is specific only to PC-3 cells and is not seen in PrEC LH cells. Moreover, this adaptation appears to be graded in response to the magnitude of FSS experienced by the cancer cells. This is the first study

  19. Phosphonic Acid-Functionalized Polyurethane Dispersions with Improved Adhesion Properties.

    Science.gov (United States)

    Breucker, Laura; Landfester, Katharina; Taden, Andreas

    2015-11-11

    A facile route to phosphorus-functionalized polyurethane dispersions (P-PUDs) with improved adhesion properties is presented. (Bis)phosphonic acid moieties serve as adhesion promoting sites that are covalently attached via an end-capping reaction to isocyanate-reactive polyurethane particles under aqueous conditions. The synthetic approach circumvents solubility issues, offers great flexibility in terms of polyurethane composition, and allows for the synthesis of semicrystalline systems with thermomechanical response due to reversible physical cross-linking. Differential scanning calorimetry (DSC) is used to investigate the effect of functionalization on the semicrystallinity. The end-capping conversion was determined via inductively-coupled plasma optical emission spectroscopy (ICP-OES) and was surprisingly found to be almost independent of the stoichiometry of reaction, suggesting an adsorption-dominated process. Particle charge detection (PCD) experiments reveal that a dense surface coverage of phosphonic acid groups can be attained and that, at high functionalization degrees, the phosphonic adhesion moieties are partially dragged inside the colloidal P-PUD particle. Quartz crystal microbalance with dissipation (QCMD) investigations conducted with hydroxyapatite (HAP) and stainless steel sensors as model surfaces show a greatly enhanced affinity of the aqueous P-PUDs and furthermore indicate polymer chain rearrangements and autonomous film formation under wet conditions. Due to their facile synthesis, significantly improved adhesion, and variable film properties, P-PUD systems such as the one described here are believed to be of great interest for multiple applications, e.g., adhesives, paints, anticorrosion, or dentistry.

  20. Altered activity and functional connectivity of superior temporal gyri in anxiety disorders: A functional magnetic resonance imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xiaohu; Xi, Qian; Wang, Peijun; Li, Chunbo [Tong Ji Hospital of Tong Ji University, Shanghai (China); He, Hongjian [Bio-X lab, Dept. of Physics, Zhe Jiang University, Hangzhou (China)

    2014-08-15

    The prior functional MRI studies have demonstrated significantly abnormal activity in the bilateral superior temporal gyrus (STG) of anxiety patients. The purpose of the current investigation was to determine whether the abnormal activity in these regions was related to a loss of functional connectivity between these regions. Ten healthy controls and 10 anxiety patients underwent noninvasive fMRI while actively listening to emotionally neutral words alternated by silence (Task 1) or threat-related words (Task 2). The participants were instructed to silently make a judgment of each word's valence (i.e., unpleasant, pleasant, or neutral). A coherence analysis was applied to the functional MRI data to examine the functional connectivity between the left and the right STG, which was selected as the primary region of interest on the basis of our prior results. The data demonstrated that the anxiety patients exhibited significantly increased activation in the bilateral STG than the normal controls. The functional connectivity analysis indicated that the patient group showed significantly decreased degree of connectivity between the bilateral STG during processing Task 2 compared to Task 1 (t = 2.588, p = 0.029). In addition, a significantly decreased connectivity was also observed in the patient group compared to the control group during processing Task 2 (t = 2.810, p = 0.012). Anxiety patients may exhibit increased activity of the STG but decreased functional connectivity between the left and right STG, which may reflect the underlying neural abnormality of anxiety disorder, and this will provide new insights into this disease.

  1. Structure-property-function relationships in triple helical collagen hydrogels

    CERN Document Server

    Tronci, Giuseppe; Russell, Stephen J; Wood, David J

    2012-01-01

    In order to establish defined biomimetic systems, type I collagen was functionalised with 1,3-Phenylenediacetic acid (Ph) as aromatic, bifunctional segment. Following investigation on molecular organization and macroscopic properties, material functionalities, i.e. degradability and bioactivity, were addressed, aiming at elucidating the potential of this collagen system as mineralization template. Functionalised collagen hydrogels demonstrated a preserved triple helix conformation. Decreased swelling ratio and increased thermo-mechanical properties were observed in comparison to state-of-the-art carbodiimide (EDC)-crosslinked collagen controls. Ph-crosslinked samples displayed no optical damage and only a slight mass decrease (~ 4 wt.-%) following 1-week incubation in simulated body fluid (SBF), while nearly 50 wt.-% degradation was observed in EDC-crosslinked collagen. SEM/EDS revealed amorphous mineral deposition, whereby increased calcium phosphate ratio was suggested in hydrogels with increased Ph content...

  2. Pedotransfer functions estimating soil hydraulic properties using different soil parameters

    DEFF Research Database (Denmark)

    Børgesen, Christen Duus; Iversen, Bo Vangsø; Jacobsen, Ole Hørbye;

    2008-01-01

    Estimates of soil hydraulic properties using pedotransfer functions (PTF) are useful in many studies such as hydrochemical modelling and soil mapping. The objective of this study was to calibrate and test parametric PTFs that predict soil water retention and unsaturated hydraulic conductivity...... parameters. The PTFs are based on neural networks and the Bootstrap method using different sets of predictors and predict the van Genuchten/Mualem parameters. A Danish soil data set (152 horizons) dominated by sandy and sandy loamy soils was used in the development of PTFs to predict the Mualem hydraulic...... of the hydraulic properties of the studied soils. We found that introducing measured water content as a predictor generally gave lower errors for water retention predictions and higher errors for conductivity predictions. The best of the developed PTFs for predicting hydraulic conductivity was tested against PTFs...

  3. Altered Biomechanical Properties of Gastrocnemius Tendons of Turkeys Infected with Turkey Arthritis Reovirus

    Directory of Open Access Journals (Sweden)

    Tamer A. Sharafeldin

    2016-01-01

    Full Text Available Turkey arthritis reovirus (TARV causes lameness and tenosynovitis in commercial turkeys and is often associated with gastrocnemius tendon rupture by the marketing age. This study was undertaken to characterize the biomechanical properties of tendons from reovirus-infected turkeys. One-week-old turkey poults were orally inoculated with O’Neil strain of TARV and observed for up to 16 weeks of age. Lameness was first observed at 8 weeks of age, which continued at 12 and 16 weeks. At 4, 8, 12, and 16 weeks of age, samples were collected from legs. Left intertarsal joint with adjacent gastrocnemius tendon was collected and processed for histological examination. The right gastrocnemius tendon’s tensile strength and elasticity modulus were analyzed by stressing each tendon to the point of rupture. At 16 weeks of age, gastrocnemius tendons of TARV-infected turkeys showed significantly reduced (P<0.05 tensile strength and modulus of elasticity as compared to those of noninfected control turkeys. Gastrocnemius tendons revealed lymphocytic tendinitis/tenosynovitis beginning at 4 weeks of age, continuing through 8 and 12 weeks, and progressing to fibrosis from 12 to 16 weeks of age. We propose that tendon fibrosis is one of the key features contributing to reduction in tensile strength and elasticity of gastrocnemius tendons in TARV-infected turkeys.

  4. Corticosteroid administration alters the mechanical properties of isolated collagen fascicles in rat-tail tendon.

    Science.gov (United States)

    Haraldsson, B T; Aagaard, P; Crafoord-Larsen, D; Kjaer, M; Magnusson, S P

    2009-10-01

    Overload tendon injuries are frequent in recreational and elite sports. The optimal treatment strategy remains unknown, but local administration of corticosteroids is one common treatment option. The direct effects of the corticosteroid administration on the tissue are not fully understood. The present study examined the biomechanical effects of intratendinous corticosteroid injections on healthy rat-tail tendon collagen fascicles. A total of 24 Wistar male rats were divided into (A) a corticosteroid group where the animals were injected in the tail tendon with methylprednisolone acetate, 1.0 mL of 40 mg/mL mixed with 1.0 mL 9% saline (n=12), and (B) a control group that was injected with 9% saline (n=12). Three days after the injections, the animals were sacrificed and single individual collagen fascicles were collected and underwent displacement to failure. Corticosteroid administration significantly reduced tensile fascicle yield strength by 16% and Young's modulus by 14% compared with sham treatment (10.5+/-0.8 vs 12.4+/-0.5 MPa, P< or =0.05, and 537+/-27 vs 641+/-30 MPa, P<0.05, respectively), while the strain properties were unaffected. Peak stress was similar between the two groups. There was no difference in fascicle diameter between the two groups.

  5. Altered resting-state amygdala functional connectivity after 36 hours of total sleep deprivation.

    Directory of Open Access Journals (Sweden)

    Yongcong Shao

    Full Text Available Recent neuroimaging studies have identified a potentially critical role of the amygdala in disrupted emotion neurocircuitry in individuals after total sleep deprivation (TSD. However, connectivity between the amygdala and cerebral cortex due to TSD remains to be elucidated. In this study, we used resting-state functional MRI (fMRI to investigate the functional connectivity changes of the basolateral amygdala (BLA and centromedial amygdala (CMA in the brain after 36 h of TSD.Fourteen healthy adult men aged 25.9 ± 2.3 years (range, 18-28 years were enrolled in a within-subject crossover study. Using the BLA and CMA as separate seed regions, we examined resting-state functional connectivity with fMRI during rested wakefulness (RW and after 36 h of TSD.TSD resulted in a significant decrease in the functional connectivity between the BLA and several executive control regions (left dorsolateral prefrontal cortex [DLPFC], right dorsal anterior cingulate cortex [ACC], right inferior frontal gyrus [IFG]. Increased functional connectivity was found between the BLA and areas including the left posterior cingulate cortex/precuneus (PCC/PrCu and right parahippocampal gyrus. With regard to CMA, increased functional connectivity was observed with the rostral anterior cingulate cortex (rACC and right precentral gyrus.These findings demonstrate that disturbance in amygdala related circuits may contribute to TSD psychophysiology and suggest that functional connectivity studies of the amygdala during the resting state may be used to discern aberrant patterns of coupling within these circuits after TSD.

  6. Altered cerebellar functional connectivity with intrinsic connectivity networks in adults with major depressive disorder.

    Directory of Open Access Journals (Sweden)

    Li Liu

    Full Text Available BACKGROUND: Numerous studies have demonstrated the higher-order functions of the cerebellum, including emotion regulation and cognitive processing, and have indicated that the cerebellum should therefore be included in the pathophysiological models of major depressive disorder. The aim of this study was to compare the resting-state functional connectivity of the cerebellum in adults with major depression and healthy controls. METHODS: Twenty adults with major depression and 20 gender-, age-, and education-matched controls were investigated using seed-based resting-state functional connectivity magnetic resonance imaging. RESULTS: Compared with the controls, depressed patients showed significantly increased functional connectivity between the cerebellum and the temporal poles. However, significantly reduced cerebellar functional connectivity was observed in the patient group in relation to both the default-mode network, mainly including the ventromedial prefrontal cortex and the posterior cingulate cortex/precuneus, and the executive control network, mainly including the superior frontal cortex and orbitofrontal cortex. Moreover, the Hamilton Depression Rating Scale score was negatively correlated with the functional connectivity between the bilateral Lobule VIIb and the right superior frontal gyrus in depressed patients. CONCLUSIONS: This study demonstrated increased cerebellar coupling with the temporal poles and reduced coupling with the regions in the default-mode and executive control networks in adults with major depression. These differences between patients and controls could be associated with the emotional disturbances and cognitive control function deficits that accompany major depression. Aberrant cerebellar connectivity during major depression may also imply a substantial role for the cerebellum in the pathophysiological models of depression.

  7. Statistical property of the Chandler wobble excitation function

    Institute of Scientific and Technical Information of China (English)

    LIAO Dechun; LIAO Xinhao; ZHOU Yonghong

    2004-01-01

    The Chandler wobble excitation function (hereinafter, geodetic excitation) is obtained by removing the seasonal components and low frequency components with periods from several years to decades from the polar motion excitation function derived from SPACE2002 series. The geophysical excitation functions of the individual AAM, OAM, HAM, and two combined excitations of the AAM + OAM and AAM + OAM + HAM at 1d, 5d, 1m and 3m intervals are statistically tested for the hypothesis of the normality, and then tested for the hypotheses of identical distribution between the geodetic and the geophysical excitations. The results show that, among the total 16 components of the two combined excitation functions at 1d, 5d, 1m and 3m intervals,most follow random normal processes, the hypotheses of identical distribution between the geodetic excitation and the two combined excitation are acceptable, while most of the hypotheses of identical distribution between the geodetic excitation and the individual excitations of the AAM, OAM, and HAM are rejectable.These results elucidate from a new point of view, that the excitations from AAM, OAM, and HAM are the main sources of the Chandler wobble, and the Chandler wobble excitation function is of a random normal property.

  8. Genetic deletion of TREK-1 or TWIK-1/TREK-1 potassium channels does not alter the basic electrophysiological properties of mature hippocampal astrocytes in situ

    Directory of Open Access Journals (Sweden)

    Yixing eDu

    2016-02-01

    Full Text Available We have recently shown that a linear current-to-voltage (I-V relationship of membrane conductance (passive conductance reflects the intrinsic property of K+ channels in mature astrocytes. While passive conductance is known to underpin a highly negative and stable membrane potential (VM essential for the basic homeostatic function of astrocytes, a complete repertoire of the involved K+ channels remains elusive. TREK-1 two-pore domain K+ channel (K2P is highly expressed in astrocytes, and covalent association of TREK-1 with TWIK-1, another highly expressed astrocytic K2P, has been reported as a mechanism underlying the trafficking of this heterodimer channel to the membrane and contributing to astrocytes’ passive conductance. To decipher the individual contribution of TREK-1 and address whether the appearance of passive conductance is conditional to the co-expression of TWIK-1/TREK-1 in astrocytes, TREK-1 single and TWIK-1/TREK-1 double gene knockout mice were used in the present study. The relative quantity of mRNA encoding other astrocyte K+ channels, such as Kir4.1, Kir5.1, and TREK-2, was not altered in these gene knockout mice. Whole-cell recording from hippocampal astrocytes in situ revealed no detectable changes in astrocyte passive conductance, VM, or membrane input resistance (Rin in either kind of gene knockout mouse. Additionally, TREK-1 proteins were mainly located in the intracellular compartments of the hippocampus. Altogether, genetic deletion of TREK-1 alone or together with TWIK-1 produced no obvious alteration in the basic electrophysiological properties of hippocampal astrocytes. Thus, future research focusing on other K+ channels may shed light on this long-standing and important question in astrocyte physiology.

  9. Prenatal exposure to cannabinoids evokes long-lasting functional alterations by targeting CB1 receptors on developing cortical neurons.

    Science.gov (United States)

    de Salas-Quiroga, Adán; Díaz-Alonso, Javier; García-Rincón, Daniel; Remmers, Floortje; Vega, David; Gómez-Cañas, María; Lutz, Beat; Guzmán, Manuel; Galve-Roperh, Ismael

    2015-11-03

    The CB1 cannabinoid receptor, the main target of Δ(9)-tetrahydrocannabinol (THC), the most prominent psychoactive compound of marijuana, plays a crucial regulatory role in brain development as evidenced by the neurodevelopmental consequences of its manipulation in animal models. Likewise, recreational cannabis use during pregnancy affects brain structure and function of the progeny. However, the precise neurobiological substrates underlying the consequences of prenatal THC exposure remain unknown. As CB1 signaling is known to modulate long-range corticofugal connectivity, we analyzed the impact of THC exposure on cortical projection neuron development. THC administration to pregnant mice in a restricted time window interfered with subcerebral projection neuron generation, thereby altering corticospinal connectivity, and produced long-lasting alterations in the fine motor performance of the adult offspring. Consequences of THC exposure were reminiscent of those elicited by CB1 receptor genetic ablation, and CB1-null mice were resistant to THC-induced alterations. The identity of embryonic THC neuronal targets was determined by a Cre-mediated, lineage-specific, CB1 expression-rescue strategy in a CB1-null background. Early and selective CB1 reexpression in dorsal telencephalic glutamatergic neurons but not forebrain GABAergic neurons rescued the deficits in corticospinal motor neuron development of CB1-null mice and restored susceptibility to THC-induced motor alterations. In addition, THC administration induced an increase in seizure susceptibility that was mediated by its interference with CB1-dependent regulation of both glutamatergic and GABAergic neuron development. These findings demonstrate that prenatal exposure to THC has long-lasting deleterious consequences in the adult offspring solely mediated by its ability to disrupt the neurodevelopmental role of CB1 signaling.

  10. One digit interruption: the altered force patterns during functionally cylindrical grasping tasks in patients with trigger digits.

    Directory of Open Access Journals (Sweden)

    Po-Tsun Chen

    Full Text Available Most trigger digit (TD patients complain that they have problems using their hand in daily or occupational tasks due to single or multiple digits being affected. Unfortunately, clinicians do not know much about how this disease affects the subtle force coordination among digits during manipulation. Thus, this study examined the differences in force patterns during cylindrical grasp between TD and healthy subjects. Forty-two TD patients with single digit involvement were included and sorted into four groups based on the involved digits, including thumb, index, middle and ring fingers. Twelve healthy subjects volunteered as healthy controls. Two testing tasks, holding and drinking, were performed by natural grasping with minimal forces. The relations between the force of the thumb and each finger were examined by Pearson correlation coefficients. The force amount and contribution of each digit were compared between healthy controls and each TD group by the independent t test. The results showed all TD groups demonstrated altered correlation patterns of the thumb relative to each finger. Larger forces and higher contributions of the index finger were found during holding by patients with index finger involved, and also during drinking by patients with affected thumb and with affected middle finger. Although no triggering symptom occurred during grasping, the patients showed altered force patterns which may be related to the role of the affected digit in natural grasping function. In conclusion, even if only one digit was affected, the subtle force coordination of all the digits was altered during simple tasks among the TD patients. This study provides the information for the future studies to further comprehend the possible injuries secondary to the altered finger coordination and also to adopt suitable treatment strategies.

  11. Alterations of Neuromuscular Function after the World's Most Challenging Mountain Ultra-Marathon.

    Directory of Open Access Journals (Sweden)

    Jonas Saugy

    Full Text Available We investigated the physiological consequences of the most challenging mountain ultra-marathon (MUM in the world: a 330-km trail run with 24000 m of positive and negative elevation change. Neuromuscular fatigue (NMF was assessed before (Pre-, during (Mid- and after (Post- the MUM in experienced ultra-marathon runners (n = 15; finish time  = 122.43 hours ±17.21 hours and in Pre- and Post- in a control group with a similar level of sleep deprivation (n = 8. Blood markers of muscle inflammation and damage were analyzed at Pre- and Post-. Mean ± SD maximal voluntary contraction force declined significantly at Mid- (-13±17% and -10±16%, P<0.05 for knee extensor, KE, and plantar flexor muscles, PF, respectively, and further decreased at Post- (-24±13% and -26±19%, P<0.01 with alteration of the central activation ratio (-24±24% and -28±34% between Pre- and Post-, P<0.05 in runners whereas these parameters did not change in the control group. Peripheral NMF markers such as 100 Hz doublet (KE: -18±18% and PF: -20±15%, P<0.01 and peak twitch (KE: -33±12%, P<0.001 and PF: -19±14%, P<0.01 were also altered in runners but not in controls. Post-MUM blood concentrations of creatine kinase (3719±3045 Ul·(1, lactate dehydrogenase (1145±511 UI·L(-1, C-Reactive Protein (13.1±7.5 mg·L(-1 and myoglobin (449.3±338.2 µg·L(-1 were higher (P<0.001 than at Pre- in runners but not in controls. Our findings revealed less neuromuscular fatigue, muscle damage and inflammation than in shorter MUMs. In conclusion, paradoxically, such extreme exercise seems to induce a relative muscle preservation process due likely to a protective anticipatory pacing strategy during the first half of MUM and sleep deprivation in the second half.

  12. Designed synthesis and chiroptical properties of regioregular poly(p-phenyleneethynylene-alter-m-phenyleneethynylene) bearing (-)-trans-rnyrtanoxyl side groups

    Institute of Scientific and Technical Information of China (English)

    Xiangfeng LI; Chusheng LI; Jiang LU; Hui LIANG

    2009-01-01

    Two regioregular poly(p-phenyleneethyny-lene-alter-m-phenyleneethynylene)s bearing (-)-trans-myrtanoxyl side groups with different substitution patterns were designed and synthesized, e.g. Myr-PMPE-1 and Myr-PMPE-2. In Myr-PMPE-1, the side chiral groups are distributed uniformly along the backbone. In Myr-PMPE-2, the distribution of the side chiral groups is alternatively crowded and loose. Both of these two polymers show no CD signal in solutions because of their good solubility. The investigations of chiroptical properties of these two polymers were carried out in the form of spin-coated films. The films were annealed above the glass temperature of the corresponding polymer, and the effects of annealing temperature and time on the properties of the films were investigated by UV-Vis absorption, fluorescence and circular dichroism spectra. The results show that annealing treatment had no significant effect on the properties of Myr-PMPE-1, including UV-Vis absorption, fluorescence and optical activity. The maximum absolute value of dissymmetry factor (|gmax|) was 1.62 × 10-4. On the other hand, annealing treatment significantly affected the proper-ties of Myr-PMPE-2. Without annealing or being annealed below 100℃, Myr-PMPE-2 films show almost no Cotton effect. In contrast, when annealed above 120℃, the absorption and emission of Myr-PMPE-2 films slightly red shifted with increasing annealing temperature and annealing time. Most importantly, the intensity of CD signals increased significantly and the optical activity of Myr-PMPE-2 films markedly increased. After annealing at 140℃ for 4h, the |gmax| of Myr-PMPE-2 films was increased up to 3.07 x 10 3, about one order of magnitude higher than that of Myr-PMPE-1 films.

  13. Functional properties and applications of edible films made of milk proteins.

    Science.gov (United States)

    Chen, H

    1995-11-01

    Edible films and coatings based on milk proteins have been developed to be used as a protective layer on foods or between food components. The most important functionalities of an edible film or coating include control of mass transfers, mechanical protection, and sensory appeal. Control of mass transfers involves preventing foods from desiccation, regulating microenvironments of gases around foods, and controlling migration of ingredients and additives in the food systems. Adequate mechanical strength of an edible film is necessary to protect the integrity of packaging throughout distribution. The sensory properties of an edible coating or film are a key factor for acceptance of final products. Simple milk protein films are good barriers to gas transfers because of their complex intermolecular bindings. Lipid is frequently incorporated into protein films to improve their properties as barriers to moisture vapor. Protein films are distinctly different in mechanical profiles from those films made of other materials. Approaches traditionally used in material sciences have been adapted and modified for studying the functionality of edible films. Potential uses of innovative processing technologies in film making to alter the film functionality are briefly discussed. A survey of potential applications of edible film based on milk protein is presented.

  14. First-episode medication-naive major depressive disorder is associated with altered resting brain function in the affective network.

    Directory of Open Access Journals (Sweden)

    Xiaocui Zhang

    Full Text Available BACKGROUND: Major depressive disorder (MDD has been associated with abnormal structure and function of the brain's affective network, including the amygdala and orbitofrontal cortex (OFC. However, it is unclear if alterations of resting-state function in this affective network are present at the initial onset of MDD. AIMS: To examine resting-state function of the brain's affective network in first-episode, medication-naive patients with MDD compared to healthy controls (HCs. METHODS: Resting-state functional magnetic resonance imaging (rs-fMRI was performed on 32 first-episode, medication-naive young adult patients with MDD and 35 matched HCs. The amplitude of low-frequency fluctuations (ALFF of the blood oxygen level-dependent (BOLD signal and amygdala-seeded functional connectivity (FC were investigated. RESULTS: Compared to HC, MDD patients showed reduced ALFF in the bilateral OFC and increased ALFF in the bilateral temporal lobe extending to the insular and left fusiform cortices. Enhanced anti-correlation of activity between the left amygdala seed and the left OFC was found in MDD patients but not in HCs. CONCLUSIONS: Reduced ALFF in the OFC suggests hypo-functioning of emotion regulation in the affective network. Enhanced anti-correlation of activity between the amygdala and OFC may reflect dysfunction of the amygdala-OFC network and additionally represent a pathological process of MDD.

  15. Altered cognitive performance and synaptic function in the hippocampus of mice lacking C3.

    Science.gov (United States)

    Perez-Alcazar, Marta; Daborg, Jonny; Stokowska, Anna; Wasling, Pontus; Björefeldt, Andreas; Kalm, Marie; Zetterberg, Henrik; Carlström, Karl E; Blomgren, Klas; Ekdahl, Christine T; Hanse, Eric; Pekna, Marcela

    2014-03-01

    Previous work implicated the complement system in adult neurogenesis as well as elimination of synapses in the developing and injured CNS. In the present study, we used mice lacking the third complement component (C3) to elucidate the role the complement system plays in hippocampus-dependent learning and synaptic function. We found that the constitutive absence of C3 is associated with enhanced place and reversal learning in adult mice. Our findings of lower release probability at CA3-CA1 glutamatergic synapses in combination with unaltered overall efficacy of these synapses in C3 deficient mice implicate C3 as a negative regulator of the number of functional glutamatergic synapses in the hippocampus. The C3 deficient mice showed no signs of spontaneous epileptiform activity in the hippocampus. We conclude that C3 plays a role in the regulation of the number and function of glutamatergic synapses in the hippocampus and exerts negative effects on hippocampus-dependent cognitive performance.

  16. Different Resting-State Functional Connectivity Alterations in Smokers and Nonsmokers with Internet Gaming Addiction

    Directory of Open Access Journals (Sweden)

    Xue Chen

    2014-01-01

    Full Text Available This study investigated changes in resting-state functional connectivity (rsFC of posterior cingulate cortex (PCC in smokers and nonsmokers with Internet gaming addiction (IGA. Twenty-nine smokers with IGA, 22 nonsmokers with IGA, and 30 healthy controls (HC group underwent a resting-state fMRI scan. PCC connectivity was determined in all subjects by investigating synchronized low-frequency fMRI signal fluctuations using a temporal correlation method. Compared with the nonsmokers with IGA, the smokers with IGA exhibited decreased rsFC with PCC in the right rectus gyrus. Left middle frontal gyrus exhibited increased rsFC. The PCC connectivity with the right rectus gyrus was found to be negatively correlated with the CIAS scores in the smokers with IGA before correction. Our results suggested that smokers with IGA had functional changes in brain areas related to motivation and executive function compared with the nonsmokers with IGA.

  17. Reproductive function of the male obese Zucker rats: alteration in sperm production and sperm DNA damage.

    Science.gov (United States)

    Vendramini, V; Cedenho, A P; Miraglia, S M; Spaine, D M

    2014-02-01

    Obesity has been considered a public health issue in many countries and is of increasing concern for authorities over the past 6 years. The Zucker rat is a good experimental model for obesity and diabetes studies due to its metabolic characteristics that are similar to those developed by humans. A total of 12 obese Zucker rats and their lean littermates were killed in pubertal and young adult phases for assessing organ weights (testis and epididymis), testicular histomorphometric and stereological analyses, daily sperm production, and transit time in the epididymis. Sperm integrity was also investigated in the adult animals using the Comet assay. Alterations in organ weights, seminiferous epithelium architecture, sperm production, and transit time were noticed in the pubertal fatty rats. The volume density of the lymphatic space was decreased in both the ages. Adult animals had a significant increase in the extent of damage found in sperm DNA. Our results show for the first time that leptin receptor deficiency compromises sperm production during puberty and that genetic obese Zucker rats have increased sperm DNA fragmentation.

  18. Expression of functions by normal sheep alveolar macrophages and their alteration by interaction with Mycoplasma ovipneumoniae.

    Science.gov (United States)

    Niang, M; Rosenbusch, R F; Lopez-Virella, J; Kaeberle, M L

    1997-10-31

    Normal sheep alveolar macrophages collected by bronchial lavage were exposed to live or heat-killed Mycoplasma ovipneumoniae organisms, and their capability to ingest Staphylococcus aureus and to elicit antibody-dependent cellular cytotoxicity against sensitized chicken red blood cells was tested. Controls consisted of non-infected macrophages in M199 medium. In addition, the effect of M. ovipneumoniae on expression of surface molecules on these sheep alveolar macrophages was determined. The percentage of S. aureus ingested by nontreated sheep alveolar macrophages was significantly higher than that of infected macrophages. Live mycoplasmas were more effective in suppressing the ingestion of S. aureus by these macrophages than killed mycoplasmas. Both live and killed mycoplasmas suppressed the cytolytic effect of the sheep alveolar macrophages to a similar degree. About 78% and 45% of the normal sheep alveolar macrophages had IgG and complement receptors, respectively. Infection of these macrophages with M. ovipneumoniae decreased significantly the expression of IgG receptors but had no effects on complement receptors. There were substantial increases in the expression of both MHC class I and class II by the mycoplasma-induced macrophages as compared with unstimulated macrophages. Live mycoplasmas were more effective in inducing expression of both classes than killed mycoplasmas. The results, taken together, suggest that M. ovipneumoniae induced alterations in macrophage activities and this may be a contributing factor in the pathogenesis of respiratory disease induced by the organism.

  19. Functional integrity of freshwater forested wetlands, hydrologic alteration, and climate change

    Science.gov (United States)

    Middleton, Beth A.; Souter, Nicholas J.;

    2016-01-01

    Climate change will challenge managers to balance the freshwater needs of humans and wetlands. The Intergovernmental Panel on Climate Change predicts that most regions of the world will be exposed to higher temperatures, CO2, and more erratic precipitation, with some regions likely to have alternating episodes of intense flooding and mega-drought. Coastal areas will be exposed to more frequent saltwater inundation as sea levels rise. Local land managers desperately need intra-regional climate information for site-specific planning, management, and restoration activities. Managers will be challenged to deliver freshwater to floodplains during climate change-induced drought, particularly within hydrologically altered and developed landscapes. Assessment of forest health, both by field and remote sensing techniques, will be essential to signal the need for hydrologic remediation. Studies of the utility of the release of freshwater to remediate stressed forested floodplains along the Murray and Mississippi Rivers suggest that brief episodes of freshwater remediation for trees can have positive health benefits for these forests. The challenges of climate change in forests of the developing world will be considered using the Tonle Sap of Cambodia as an example. With little ecological knowledge of the impacts, managing climate change will add to environmental problems already faced in the developing world with new river engineering projects. These emerging approaches to remediate stressed trees will be of utmost importance for managing worldwide floodplain forests with predicted climate changes.

  20. Alterations of cardiovascular functional parameters after onset of heat stroke in rats.

    Science.gov (United States)

    Young, M S; Pan, H F; Kao, T Y; Lin, M T

    1993-01-01

    The effects of heat stroke formation on electrocardiogram (ECG) and blood pressure (BP) waveform parameters were assessed in rats under urethane anesthesia. Heat stroke was induced by exposing anesthetized rats to an environmental temperature of 42 degrees C. The movement in which arterial pressure began to decrease was taken as the onset of heat stroke. It was found that the duration of either P were, Q wave, R wave, S wave, T wave or QRS complex, as well as the amplitude of either P wave, Q wave, S wave or T wave were not affected after onset of heat stroke. However, the amplitude of R wave, the P-P interval, the R-R interval and the Q-T interval were significantly decreased after onset of heat stroke. In addition, the peak amplitude of systolic wave, dicrotic notch, diastolic wave, the duration of either systolic wave, a whole BP cycle, diastolic wave or dicrotic wave, the pulse pressure, as well as the mean arterial pressure were also decreased after onset of heat stroke. On the other hand, heat stroke formation increased the heart rate. The results demonstrated that alterations of these ECG and BP waveform parameters occurred after onset of heat stroke in rats.

  1. Ex vivo stretch reveals altered mechanical properties of isolated dystrophin-deficient hearts.

    Directory of Open Access Journals (Sweden)

    Matthew S Barnabei

    Full Text Available Duchenne muscular dystrophy (DMD is a progressive and fatal disease of muscle wasting caused by loss of the cytoskeletal protein dystrophin. In the heart, DMD results in progressive cardiomyopathy and dilation of the left ventricle through mechanisms that are not fully understood. Previous reports have shown that loss of dystrophin causes sarcolemmal instability and reduced mechanical compliance of isolated cardiac myocytes. To expand upon these findings, here we have subjected the left ventricles of dystrophin-deficient mdx hearts to mechanical stretch. Unexpectedly, isolated mdx hearts showed increased left ventricular (LV compliance compared to controls during stretch as LV volume was increased above normal end diastolic volume. During LV chamber distention, sarcomere lengths increased similarly in mdx and WT hearts despite greater excursions in volume of mdx hearts. This suggests that the mechanical properties of the intact heart cannot be modeled as a simple extrapolation of findings in single cardiac myocytes. To explain these findings, a model is proposed in which disruption of the dystrophin-glycoprotein complex perturbs cell-extracellular matrix contacts and promotes the apparent slippage of myocytes past each other during LV distension. In comparison, similar increases in LV compliance were obtained in isolated hearts from β-sarcoglycan-null and laminin-α(2 mutant mice, but not in dysferlin-null mice, suggesting that increased whole-organ compliance in mdx mice is a specific effect of disrupted cell-extracellular matrix contacts and not a general consequence of cardiomyopathy via membrane defect processes. Collectively, these findings suggest a novel and cell-death independent mechanism for the progressive pathological LV dilation that occurs in DMD.

  2. Physical Properties of Blood Are Altered in Young and Lean Women with Polycystic Ovary Syndrome

    Science.gov (United States)

    Simmonds, Michael J.; Milne, Nikki; Ong, Kee; Brotherton, Emily; McNamee, Antony P.; Horobin, Jarod; Sabapathy, Surendran

    2016-01-01

    Classic features of polycystic ovary syndrome (PCOS) include derangement of metabolic and cardiovascular health, and vascular dysfunction is commonly reported. These comorbidities indicate impaired blood flow; however, other than limited reports of increased plasma viscosity, surprisingly little is known regarding the physical properties of blood in PCOS. We aimed to investigate whether haemorheology was impaired in women with PCOS. We thus measured a comprehensive haemorheological profile, in a case-control design, of lean women with PCOS and age-matched healthy controls. A clinical examination determined similar cardiovascular risk for the two groups. Whole blood and plasma viscosity was measured using a cone-plate viscometer. The magnitude and rate of red blood cell (RBC) aggregation was determined using a light-transmission aggregometer, and the degree of RBC deformability was measured via laser-diffraction ektacytometry. Plasma viscosity was significantly increased in women with PCOS. Blood viscosity was also increased for PCOS at lower-to-moderate shear rates in both native and standardised haematocrit samples. The magnitude of RBC aggregation–a primary determinant of low-shear blood viscosity–was significantly increased in PCOS at native and 0.4 L·L-1 haematocrit. No difference was detected between PCOS and CON groups for RBC deformability measurements. A novel measure indicating the effectiveness of oxygen transport by RBC (i.e., the haematocrit-to-viscosity ratio; HVR) was decreased at all shear rates in women with PCOS. In a group of young and lean women with PCOS with an unremarkable cardiovascular risk profile based on clinical data, significant haemorheological impairment was observed. The degree of haemorheological derangement observed in the present study reflects that of overt chronic disease, and provides an avenue for future therapeutic intervention in PCOS. PMID:27902766

  3. Muscle cramp in Machado-Joseph disease: altered motor axonal excitability properties and mexiletine treatment.

    Science.gov (United States)

    Kanai, Kazuaki; Kuwabara, Satoshi; Arai, Kimihito; Sung, Jia-Ying; Ogawara, Kazue; Hattori, Takamichi

    2003-04-01

    Machado-Joseph disease is one of the most common hereditary spinocerebellar degenerative disorders with a wide range of clinical manifestations. Pathology studies have shown mild to moderate loss of anterior horn cells and, in terms of spinal pathology, Machado-Joseph disease is regarded as a type of lower motoneuron disease. Muscle cramps are often associated with lower motoneuron disorders, but features of cramps in Machado-Joseph disease patients have never been studied. We investigated the incidence and nature of muscle cramps in Machado-Joseph disease patients, the excitability properties of motor axons [strength-duration time constant (tau(SD)), threshold electrotonus, refractoriness and supernormality] using threshold tracking and the effects of mexiletine hydrochloride on those cramps. Of 20 consecutive patients, 16 (80%) had frequent, severe muscle cramps in the legs, trunk or arms that disturbed their daily activities. The frequency of pathological muscle cramps was similar to that for patients with amyotrophic lateral sclerosis (68%) and higher than those for patients with spinal muscular atrophy (33%) or peripheral axonal neuropathy (24%). Threshold-tracking studies showed that tau(SD), which in part reflects Na(+) conductance at the resting membrane potential, was significantly greater in the Machado-Joseph disease patients than in normal subjects; severe muscle cramps were associated with a longer tau(SD). Threshold electrotonus, refractoriness and supernormality were not significantly different between Machado-Joseph disease patients and normal subjects. Eight Machado-Joseph disease patients with severe cramps, who received mexiletine treatment, experienced nearly complete relief with a partial normalization of tau(SD) (P = 0.08). Muscle cramps are a very frequent and disabling factor in Machado-Joseph disease. Pathological muscle cramps responded well to mexiletine treatment, and this is consistent with the hypothesis that they are caused by an

  4. Characterization and petrophysical properties of hydrothemally altered lacustrine volcanistic rock in Geyser Valley (Kamchatka) and its transformation by weathering

    Science.gov (United States)

    Gvozdeva, Irina; Zerkal, Oleg; Samarin, Evgeny

    2013-04-01

    content of clay minerals (to 90%), decreasing the content of zeolites (not to exceed 10%). Quartz and plagioclase form sans fraction. Physical and mechanical properties vary widely: the density of the soil increases slightly up to 1,57-1,59 g/cm3 for sands, 1,2-1,79 g/cm3 for clays, porosity of 51-52% and 49-78% respectively, moisture 22-23% and 43-98/ Clays are in a state of semi-solid to fluid. The high content of smectite determines high plastic properties. Plasticity Index varies widely from 11 to 57. Cohesion and the internal friction angle obtained from shear tests also change widely. For clayey sand grip reaches 137 kPa, internal friction angle - 17 degrees. In clay grip ranges from 13 kPa to 120 kPa, and the internal friction angle - from 11 degrees to 31 degrees. Large variation of properties of the investigated soils is explained by the inhomogeneity of volcano-sedimentary formations both vertically and laterally, varying degrees of hydrothermal alteration and of weathering, fracturing and cracks filling The obtained datas can adequately characterize the volcanic-lacustrine sediments in the valley of the Geysernaya river and use them in calculations of slope stability and for and geological mapping.

  5. Multiple alterations of platelet functions dominated by increased secretion in mice lacking Cdc42 in platelets

    DEFF Research Database (Denmark)

    Pleines, Irina; Eckly, Anita; Elvers, Margitta;

    2010-01-01

    formation and exocytosis in various cell types, but its exact function in platelets is not established. Here, we show that the megakaryocyte/platelet-specific loss of Cdc42 leads to mild thrombocytopenia and a small increase in platelet size in mice. Unexpectedly, Cdc42-deficient platelets were able to form...... reduced, suggesting increased clearing of the cells under physiologic conditions. These data point to novel multiple functions of Cdc42 in the regulation of platelet activation, granule organization, degranulation, and a specific role in GPIb signaling....

  6. Prenatal undernutrition and postnatal overnutrition alter thyroid hormone axis function in sheep

    DEFF Research Database (Denmark)

    Johnsen, Lærke; Kongsted, Anna Hauntoft; Nielsen, Mette Olaf

    2013-01-01

    -bearing sheep were fed one of two diets during late gestation: NORM (fulfilling energy and protein requirements) or LOW (50% of NORM). From day-3 to 6-months after birth (around puberty) the twin lambs were assigned to each their diet: conventional (CONV) or high-carbohydrate-high-fat (HCHF), where after half......Mounting evidence led us to hypothesize that: 1) function of the thyroid hormone (TH) axis can be programmed by late-gestation undernutrition (LG-UN), and 2) early-postnatal-life overnutrition (EL-ON) exacerbates the fetal impacts on TH-axis function. In a 2×2 factorial experiment, 21 twin...

  7. Some properties of the Feynman-Kac functional

    Directory of Open Access Journals (Sweden)

    S. Graversen

    1995-01-01

    Full Text Available The Feynman-Kac formula and its connections with classical analysis were initiated in the now celebrated paper [6] of M. Kac. It soon became obvious that the formula provides a powerful tool for solving partial differential equations by running the Brownian motion process. K.L. Chung and K.M. Rao in [4] used it to characterize solutions of the Schrödinger equation. In this paper we study some properties of the Feynman-Kac functional using the Brownian motion process. In particular, we are going to use it in connection with the gauge function in order to obtain an energy formula similar to one obtained by G. Dal Maso and U. Mosco in [5].

  8. Electronic properties of graphene nanoribbons: A density functional investigation

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sandeep, E-mail: skumar198712@gmail.com; Sharma, Hitesh, E-mail: dr.hitesh.phys@gmail.com [Department of Physics, Punjab Technical University Kapurthala, Punjab-144601 (India)

    2015-05-15

    Density functional theory calculations have been performed on graphene nano ribbons (GNRs) to investigate the electronic properties as a function of chirality, size and hydrogenation on the edges. The calculations were performed on GNRs with armchair and zigzag configurations with 28, 34, 36, 40, 50, 56, 62, 66 carbon atoms. The structural stability of AGNR and ZGNR increases with the size of nanoribbon where as hydrogenation of GNR tends to lowers their structural stability. All GNRs considered have shown semiconducting behavior with HOMO-LUMO gap decreasing with the increase in the GNR size. The hydrogenation of GNR decreases its HOMO-LUMO gap significantly. The results are in agreement with the available experimental and theoretical results.

  9. Altered Expression Pattern of Molecular Factors Involved in Colonic Smooth Muscle Functions: An Immunohistochemical Study in Patients with Diverticular Disease

    Science.gov (United States)

    Mattii, Letizia; Ippolito, Chiara; Segnani, Cristina; Battolla, Barbara; Colucci, Rocchina; Dolfi, Amelio; Bassotti, Gabrio; Blandizzi, Corrado; Bernardini, Nunzia

    2013-01-01

    Background The pathogenesis of diverticular disease (DD) is thought to result from complex interactions among dietary habits, genetic factors and coexistence of other bowel abnormalities. These conditions lead to alterations in colonic pressure and motility, facilitating the formation of diverticula. Although electrophysiological studies on smooth muscle cells (SMCs) have investigated colonic motor dysfunctions, scarce attention has been paid to their molecular abnormalities, and data on SMCs in DD are lacking. Accordingly, the main purpose of this study was to evaluate the expression patterns of molecular factors involved in the contractile functions of SMCs in the tunica muscularis of colonic specimens from patients with DD. Methods and Findings By means of immunohistochemistry and image analysis, we examined the expression of Cx26 and Cx43, which are prominent components of gap junctions in human colonic SMCs, as well as pS368-Cx43, PKCps, RhoA and αSMA, all known to regulate the functions of gap junctions and the contractile activity of SMCs. The immunohistochemical analysis revealed significant abnormalities in DD samples, concerning both the expression and distribution patterns of most of the investigated molecular factors. Conclusion This study demonstrates, for the first time, that an altered pattern of factors involved in SMC contractility is present at level of the tunica muscularis of DD patients. Moreover, considering that our analysis was conducted on colonic tissues not directly affected by diverticular lesions or inflammatory reactions, it is conceivable that these molecular alterations may precede and predispose to the formation of diverticula, rather than being mere consequences of the disease. PMID:23437299

  10. Worse than Sticks and Stones? Bullying Is Associated with Altered HPA Axis Functioning and Poorer Health

    Science.gov (United States)

    Knack, Jennifer M.; Jensen-Campbell, Lauri A.; Baum, Andrew

    2011-01-01

    Adolescents (N = 107; M = 12.23 years, SD = 1.09 months) participated in a two-part study examining peer victimization, neuroendocrine functioning, and physical health. In phase 1, adolescents completed questionnaires assessing peer victimization and health. They returned for phase 2 which consisted of two sessions. In session 1, adolescents…

  11. Mitochondrial (dys)function in adipocyte (de)-differentiation and systemic metabolic alterations

    NARCIS (Netherlands)

    Pauw, de A.; Tejerina, S.; Raes, M.; Keijer, J.; Arnould, T.

    2009-01-01

    In mammals, adipose tissue, composed of BAT and WAT, collaborates in energy partitioning and performs metabolic regulatory functions. It is the most flexible tissue in the body, because it is remodeled in size and shape by modifications in adipocyte cell size and/or number, depending on developmenta

  12. Ionizing radiation selectively reduces skin regulatory T cells and alters immune function.

    Directory of Open Access Journals (Sweden)

    Yu Zhou

    Full Text Available The skin serves multiple functions that are critical for life. The protection from pathogens is achieved by a complicated interaction between aggressive effectors and controlling functions that limit damage. Inhomogeneous radiation with limited penetration is used in certain types of therapeutics and is experienced with exposure to solar particle events outside the protection of the Earth's magnetic field. This study explores the effect of ionizing radiation on skin immune function. We demonstrate that radiation, both homogeneous and inhomogeneous, induces inflammation with resultant specific loss of regulatory T cells from the skin. This results in a hyper-responsive state with increased delayed type hypersensitivity in vivo and CD4+ T cell proliferation in vitro. The effects of inhomogeneous radiation to the skin of astronauts or as part of a therapeutic approach could result in an unexpected enhancement in skin immune function. The effects of this need to be considered in the design of radiation therapy protocols and in the development of countermeasures for extended space travel.

  13. Ionizing Radiation Selectively Reduces Skin Regulatory T Cells and Alters Immune Function

    Science.gov (United States)

    Zhou, Yu; Ni, Houping; Balint, Klara; Sanzari, Jenine K.; Dentchev, Tzvete; Diffenderfer, Eric S.; Wilson, Jolaine M.; Cengel, Keith A.; Weissman, Drew

    2014-01-01

    The skin serves multiple functions that are critical for life. The protection from pathogens is achieved by a complicated interaction between aggressive effectors and controlling functions that limit damage. Inhomogeneous radiation with limited penetration is used in certain types of therapeutics and is experienced with exposure to solar particle events outside the protection of the Earth’s magnetic field. This study explores the effect of ionizing radiation on skin immune function. We demonstrate that radiation, both homogeneous and inhomogeneous, induces inflammation with resultant specific loss of regulatory T cells from the skin. This results in a hyper-responsive state with increased delayed type hypersensitivity in vivo and CD4+ T cell proliferation in vitro. The effects of inhomogeneous radiation to the skin of astronauts or as part of a therapeutic approach could result in an unexpected enhancement in skin immune function. The effects of this need to be considered in the design of radiation therapy protocols and in the development of countermeasures for extended space travel. PMID:24959865

  14. HEMOSTATIC FUNCTION OF ASPIRIN-TREATED PLATELETS VULNERABLE TO CARDIOPULMONARY BYPASS - ALTERED SHEAR-INDUCED PATHWAY

    NARCIS (Netherlands)

    TABUCHI, N; HUET, RCGG; STURK, A; EIJSMAN, L; WILDEVUUR, CRH

    1995-01-01

    The impaired hemostasis of aspirin-treated patients is an annoying problem during and after cardiopulmonary bypass, The hemostatic function of platelets comprises two mechanisms: the shear-induced and the cyclooxygenase pathways, Because the latter is inhibited in aspirin-treated patients, the hemos

  15. Altered brain functional connectivity in relation to perception of scrutiny in social anxiety disorder.

    Science.gov (United States)

    Giménez, Mónica; Pujol, Jesús; Ortiz, Hector; Soriano-Mas, Carles; López-Solà, Marina; Farré, Magí; Deus, Joan; Merlo-Pich, Emilio; Martín-Santos, Rocio

    2012-06-30

    Although the fear of being scrutinized by others in a social context is a key symptom in social anxiety disorder (SAD), the neural processes underlying the perception of scrutiny have not previously been studied by functional magnetic resonance imaging (fMRI). We used fMRI to map brain activation during a perception-of-scrutiny task in 20 SAD patients and 20 controls. A multi-dimensional analytic approach was used. Scrutiny perception was mediated by activation of the medial frontal cortex, insula-operculum region and cerebellum, and the additional recruitment of visual areas and the thalamus in patients. Between-group comparison demonstrated significantly enhanced brain activation in patients in the primary visual cortex and cerebellum. Functional connectivity mapping demonstrated an abnormal connectivity between regions underlying general arousal and attention. SAD patients showed significantly greater task-induced functional connectivity in the thalamo-cortical and the fronto-striatal circuits. A statistically significant increase in task-induced functional connectivity between the anterior cingulate cortex and scrutiny-perception-related regions was observed in the SAD patients, suggesting the existence of enhanced behavior-inhibitory control. The presented data indicate that scrutiny perception in SAD enhances brain activity in arousal-attention systems, suggesting that fMRI may be a useful tool to explore such a behavioral dimension.

  16. Early association of electrocardiogram alteration with infarct size and cardiac function after myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    陶则伟; 黄元伟; 夏强; 傅军; 赵志宏; 陆贤; BRUCEI.C.

    2004-01-01

    Objective:Myocardial infarction (MI) is the main cause of heart failure, but the relationship between the extent of MI and cardiac function has not been clearly determined.The present study was undertaken to investigate early changes in the electrocardiogram associated with infarct size and cardiac function after MI. Methods: MI was induced by ligating the left anterior descending coronary artery in rats. Electrocardiograms, echocardiographs and hemodynamic parameters were assessed and myocardial infarct size was measured from mid-transverse sections stained with Masson's trichrome. Results:The sum of pathological Q wave amplitudes was strongly correlated with myocardial infarct size (r=0.920, P<0.0001), left ventricular ejection fraction (r=-0.868, P<0.0001) and left ventricular end diastolic pressure (r=0.835, P<0.0004).Furthermore, there was close relationship between MI size and cardiac function as assessed by left ventricular ejection fraction (r=-0.913, P<0.0001) and left ventricular end diastolic pressure (r=0.893, P<0.0001).Conclusion: The sum of pathological Q wave amplitudes after MI can be used to estimate the extent of MI as well as cardiac function.

  17. Early association of electrocardiogram alteration with infarct size and cardiac function after myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    TAO Ze-wei (陶则伟); HUANG Yuan-wei (黄元伟); XIA Qiang (夏强); FU Jun (傅军); ZHAO Zhi-hong (赵志宏); LU Xian (陆贤); BRUCE I.C.

    2004-01-01

    Objective: Myocardial infarction (MI) is the main cause of heart failure, but the relationship between the extent of MI and cardiac function has not been clearly determined. The present study was undertaken to investigate early changes in the electrocardiogram associated with infarct size and cardiac function after MI. Methods: MI was induced by ligating the left anterior descending coronary artery in rats. Electrocardiograms, echocardiographs and hemodynamic parameters were assessed and myocardial infarct size was measured from mid-transverse sections stained with Masson's trichrome. Results: The sum of pathological Q wave amplitudes was strongly correlated with myocardial infarct size (r = 0.920, P < 0.0001), left ventricular ejection fraction (r = (0.868, P < 0.0001) and left ventricular end diastolic pressure (r = 0.835, P < 0.0004). Furthermore, there was close relationship between MI size and cardiac function as assessed by left ventricular ejection fraction (r = (0.913, P < 0.0001) and left ventricular end diastolic pressure (r = 0.893, P < 0.0001). Conclusion: The sum of pathological Q wave amplitudes after MI can be used to estimate the extent of MI as well as cardiac function.

  18. Acute brief heat stress in late gestation alters neonatal calf innate immune functions

    Science.gov (United States)

    Heat stress (HS), as one of the environmental stressors affecting the dairy industry, compromises the cow's milk production, immune function, and reproductive system. However, few studies have looked at how prenatal HS affects the offspring. The objective of this study was to evaluate the effect of ...

  19. Information Functional Theory: Electronic Properties as Functionals of Information for Atoms and Molecules.

    Science.gov (United States)

    Zhou, Xia-Yu; Rong, Chunying; Lu, Tian; Zhou, Panpan; Liu, Shubin

    2016-05-26

    How to accurately predict electronic properties of a Columbic system with the electron density obtained from experiments such as X-ray crystallography is still an unresolved problem. The information-theoretic approach recently developed in the framework of density functional reactivity theory is one of the efforts to address the issue. In this work, using 27 atoms and 41 molecules as illustrative examples, we present a study to demonstrate that one is able to satisfactorily describe such electronic properties as the total energy and its components with information-theoretic quantities like Shannon entropy, Fisher information, Ghosh-Berkowitz-Parr entropy, and Onicescu information energy. Closely related to the earlier attempt of expanding density functionals using simple homogeneous functionals, this work not only confirms Nagy's proof that Shannon entropy alone should contain all the information needed to adequately describe an electronic system but also provides a feasible pathway to map the relationship between the experimentally available electron density and various electronic properties for Columbic systems such as atoms and molecules. Extensions to other electronic properties are straightforward.

  20. Obesity and weight loss could alter the properties ofadipose stem cells?

    Institute of Scientific and Technical Information of China (English)

    Leandra S Baptista; Karina R Silva; Radovan Borojevic

    2015-01-01

    The discovery that adipose tissue represents aninteresting source of multipotent stem cells has ledto many studies exploring the clinical potential ofthese cells in cell-based therapies. Recent advances inunderstanding the secretory capacity of adipose tissueand the role of adipokines in the development of obesityand associated disorders have added a new dimensionto the study of adipose tissue biology in normal anddiseased states. Subcutaneous adipose tissue forms theinterface between the clinical application of regenerativemedicine and the establishment of the pathologicalcondition of obesity. These two facets of adipose tissueshould be understood as potentially related phenomena.Because of the functional characteristics of adiposestem cells, these cells represent a fundamental tool forunderstanding how these two facets are interconnectedand could be important for therapeutic applications.In fact, adipose tissue stem cells have multiplefunctions in obesity related to adipogenic, angiogenicand secretory capacities. In addition, we have alsopreviously described a predominance of larger bloodvessels and an adipogenic memory in the subcutaneousadipose tissue after massive weight loss subsequent tobariatric surgery (ex-obese patients). Understandingthe reversibility of the behavior of adipose stemcells in obeses and in weight loss is relevant to bothphysiological studies and the potential use of these cellsin regenerative medicine.

  1. Structure alteration and immunological properties of {sup 60}Co gamma rays irradiated bothropstoxin-I

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Janaina A.; Yonamine, Camila Myiagui; Caproni, Priscila; Casare, Murilo; Spencer, Patrick Jack; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: janabap@gmail.com; Andrade Junior, Heitor Franco de; Vieira, Daniel Perez; Galisteo Junior, Andres Jimenez [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Instituto de Medicina Tropical de Sao Paulo, SP (Brazil). Lab. de Protozoologia

    2007-07-01

    About 20000 ophidic accidents are registered every year in Brazil. Serum therapy with equine antisera is the only efficient treatment. The venoms employed for immunization are fairly toxic and some venoms present low immunogenicity. Thus, the obtention of modified antigens with lower toxicity and preserved or improved immunogenicity would be useful. These toxins, when submitted to gamma radiation, in aqueous solution, present structural modifications. This occurs due to reactions with the radiolysis products of water. Some scavenger substances, such as NaNO{sub 3} and t-butanol, remove selectively the water radiolysis products. Ionizing radiation has proven to be a powerful tool to attenuate snake venoms toxicity without affecting and even increasing their immunogenic properties. However, the immune mechanisms involved in recognition, processing and presentation of irradiated antigens are yet unclear. In the present work, we investigated the immunological behavior of bothropstoxin-I (Bthx-1), before and after irradiation, in the presence of selective scavengers. Isogenic mice were immunized with either the native or the irradiated toxin, either with or without scavengers. After three immunizations, serum samples were collected and the antibody titers and isotypes were determined by Enzyme Linked Immuno Sorbent Assay. The antigenic characterization of native and irradiated bothropstoxin-I was performed by Western blot. The detection of expression of murine cytokines (IFN-{gamma} and IL-10) was analyzed by RT-PCR (Reverse Transcriptase-Polymerase Chain Reaction). According to our data, irradiation process has promoted structural modifications in the toxin, characterized by higher molecular weight forms of the protein (aggregates and oligomers). Our data also indicate that irradiated toxins, alone or in the presence of NaNO{sub 3}, an aqueous electron scavenger, were immunogenic and the antibodies elicited by them were able to recognize the native toxin. On the other

  2. Psychometric properties of the Nurses Work Functioning Questionnaire (NWFQ.

    Directory of Open Access Journals (Sweden)

    Fania R Gärtner

    Full Text Available OBJECTIVES: The Nurses Work Functioning Questionnaire (NWFQ is a 50-item self-report questionnaire specifically developed for nurses and allied health professionals. Its seven subscales measure impairments in the work functioning due to common mental disorders. Aim of this study is to evaluate the psychometric properties of the NWFQ, by assessing reproducibility and construct validity. METHODS: The questionnaire was administered to 314 nurses and allied health professionals with a re-test in 112 subjects. Reproducibility was assessed by the intraclass correlations coefficients (ICC and the standard error of measurement (SEM. For construct validity, correlations were calculated with a general work functioning scale, the Endicott Work Productivity Scale (EWPS (convergent validity and with a physical functioning scale (divergent validity. For discriminative validity, a Mann Whitney U test was performed testing for significant differences between subjects with mental health complaints and without. RESULTS: All subscales showed good reliability (ICC: 0.72-0.86, except for one (ICC = 0.16. Convergent validity was good in six subscales, correlations ranged from 0.38-0.62. However, in one subscale the correlation with the EWPS was too low (0.22. Divergent validity was good in all subscales based on correlations ranged from (-0.06-(-0.23. Discriminative validity was good in all subscales, based on significant differences between subjects with and without mental health complaints (p<0.001-p = 0.003. CONCLUSION: The NWFQ demonstrates good psychometric properties, for six of the seven subscales. Subscale "impaired decision making" needs improvement before further use.

  3. The presence of serum alters the properties of iron oxide nanoparticles and lowers their accumulation by cultured brain astrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Geppert, Mark; Petters, Charlotte [University of Bremen, Centre for Biomolecular Interactions Bremen (Germany); Thiel, Karsten [Fraunhofer Institute for Manufacturing Technology and Advanced Materials (Germany); Dringen, Ralf, E-mail: ralf.dringen@uni-bremen.de [University of Bremen, Centre for Biomolecular Interactions Bremen (Germany)

    2013-01-15

    Iron oxide nanoparticles (IONPs) are considered for various diagnostic and therapeutic applications. Such particles are able to cross the blood-brain barrier and are taken up into brain cells. To test whether serum components affect the properties of IONPs and/or their uptake into brain cells, we have incubated dimercaptosuccinate-coated magnetic IONPs without and with fetal calf serum (FCS) and have exposed cultured brain astrocytes with IONPs in the absence or presence of FCS. Incubation with FCS caused a concentration-dependent increase in the average hydrodynamic diameter of the particles and of their zeta-potential. In the presence of 10 % FCS, the diameter of the IONPs increased from 57 {+-} 2 to 107 {+-} 6 nm and the zeta-potential of the particles from -22 {+-} 5 to -9 {+-} 1 mV. FCS affected also strongly the uptake of IONPs by cultured astrocytes. The efficient time- and temperature-dependent cellular accumulation of IONPs was lowered with increasing concentration of FCS by up to 90 %. In addition, in the absence of serum, endocytosis inhibitors did not alter the IONP accumulation by astrocytes, while chlorpromazine or wortmannin lowered significantly the accumulation of IONPs in the presence of FCS, suggesting that clathrin-mediated endocytosis and macropinocytosis are involved in astrocytic IONP uptake from serum-containing medium. These data demonstrate that the presence of FCS strongly affects the properties of IONPs as well as their accumulation by cultured brain cells.

  4. Exopolymer alteration of physical properties of sea ice and implications for ice habitability and biogeochemistry in a warmer Arctic.

    Science.gov (United States)

    Krembs, Christopher; Eicken, Hajo; Deming, Jody W

    2011-03-01

    The physical properties of Arctic sea ice determine its habitability. Whether ice-dwelling organisms can change those properties has rarely been addressed. Following discovery that sea ice contains an abundance of gelatinous extracellular polymeric substances (EPS), we examined the effects of algal EPS on the microstructure and salt retention of ice grown from saline solutions containing EPS from a culture of the sea-ice diatom, Melosira arctica. We also experimented with xanthan gum and with EPS from a culture of the cold-adapted bacterium Colwellia psychrerythraea strain 34H. Quantitative microscopic analyses of the artificial ice containing Melosira EPS revealed convoluted ice-pore morphologies of high fractal dimension, mimicking features found in EPS-rich coastal sea ice, whereas EPS-free (control) ice featured much simpler pore geometries. A heat-sensitive glycoprotein fraction of Melosira EPS accounted for complex pore morphologies. Although all tested forms of EPS increased bulk ice salinity (by 11-59%) above the controls, ice containing native Melosira EPS retained the most salt. EPS effects on ice and pore microstructure improve sea ice habitability, survivability, and potential for increased primary productivity, even as they may alter the persistence and biogeochemical imprint of sea ice on the surface ocean in a warming climate.

  5. Nematomorph parasites indirectly alter the food web and ecosystem function of streams through behavioural manipulation of their cricket hosts.

    Science.gov (United States)

    Sato, T.; Egusa, T.; Fukushima, K.; Oda, T.; Ohte, N.; Tokuchi, Naoko; Watanabe, Katsutoshi; Kanaiwa, Minoru; Murakami, Isaya; Lafferty, Kevin D.

    2012-01-01

    Nematomorph parasites manipulate crickets to enter streams where the parasites reproduce. These manipulated crickets become a substantial food subsidy for stream fishes. We used a field experiment to investigate how this subsidy affects the stream community and ecosystem function. When crickets were available, predatory fish ate fewer benthic invertebrates. The resulting release of the benthic invertebrate community from fish predation indirectly decreased the biomass of benthic algae and slightly increased leaf break-down rate. This is the first experimental demonstration that host manipulation by a parasite can reorganise a community and alter ecosystem function. Nematomorphs are common, and many other parasites have dramatic effects on host phenotypes, suggesting that similar effects of parasites on ecosystems might be widespread.

  6. Trauma-Related Altered States of Consciousness (TRASC) and Functional Impairment II: Perceived Causal Relationships in an Online Sample.

    Science.gov (United States)

    Tzannidakis, Nicole C A; Frewen, Paul

    2015-01-01

    Research supports the existence of a dissociative subtype of posttraumatic stress disorder, although studies have not directly compared the perceived impact of dissociative versus nondissociative posttraumatic symptoms on social and occupational functioning. In addition, research is beginning to differentiate between posttraumatic distress associated with normal waking consciousness (NWC) and dissociative experiences of trauma-related altered states of consciousness (TRASC) along multiple phenomenological dimensions. The current study investigated perceived causal relationships between posttraumatic symptoms associated with NWC-distress and TRASC on the one hand and interpersonal and occupational functioning on the other. Although both TRASC and NWC-distress independently accounted for variance in self-reported interpersonal and occupational problems, perceived causal relationship results showed that individuals tended to attribute their social and work-related problems more strongly to NWC-distress than to TRASC. Future research directions are discussed.

  7. Wfs1-deficient mice display altered function of serotonergic system and increased behavioural response to antidepressants

    Directory of Open Access Journals (Sweden)

    Tanel eVisnapuu

    2013-07-01

    Full Text Available It has been shown that mutations in the WFS1 gene make humans more susceptible to mood disorders. Besides that, mood disorders are associated with alterations in the activity of serotonergic and noradrenergic systems. Therefore, in this study, the effects of imipramine, an inhibitor of serotonin (5-HT and noradrenaline (NA reuptake, and paroxetine, a selective inhibitor of 5-HT reuptake, were studied in tests of behavioural despair. The tail suspension test (TST and forced swimming test (FST were performed in Wfs1-deficient mice. Simultaneously, gene expression and monoamine metabolism studies were conducted to evaluate changes in 5-HT- and NA-ergic systems of Wfs1-deficient mice. The basal immobility time of Wfs1-deficient mice in TST and FST did not differ from that of their wild-type littermates. However, a significant reduction of immobility time in response to lower doses of imipramine and paroxetine was observed in homozygous Wfs1-deficient mice, but not in their wild-type littermates. In gene expression studies, the levels of 5-HT transporter (SERT were significantly reduced in the pons of homozygous animals. Monoamine metabolism was assayed separately in the dorsal and ventral striatum of naive mice and mice exposed for 30 minutes tobrightly lit motility boxes. We found that this aversive challenge caused a significant increase in the levels of 5-HT and 5-hydroxyindoleacetic acid (5-HIAA, a metabolite of 5-HT, in the ventral and dorsal striatum of wild-type mice, but not in their homozygous littermates. Taken together, the blunted 5-HT metabolism and reduced levels of SERT are a likely reason for the elevated sensitivity of these mice to the action of imipramine and paroxetine. These changes in the pharmacological and neurochemical phenotype of Wfs1-deficient mice may help to explain the increased susceptibility of Wolfram syndrome patients to depressive states.

  8. Characterization of 4-HNE modified L-FABP reveals alterations in structural and functional dynamics.

    Science.gov (United States)

    Smathers, Rebecca L; Fritz, Kristofer S; Galligan, James J; Shearn, Colin T; Reigan, Philip; Marks, Michael J; Petersen, Dennis R

    2012-01-01

    4-Hydroxynonenal (4-HNE) is a reactive α,β-unsaturated aldehyde produced during oxidative stress and subsequent lipid peroxidation of polyunsaturated fatty acids. The reactivity of 4-HNE towards DNA and nucleophilic amino acids has been well established. In this report, using proteomic approaches, liver fatty acid-binding protein (L-FABP) is identified as a target for modification by 4-HNE. This lipid binding protein mediates the uptake and trafficking of hydrophobic ligands throughout cellular compartments. Ethanol caused a significant decrease in L-FABP protein (PL-FABP (PL-FABP were mapped using MALDI-TOF/TOF mass spectrometry on apo (Lys57 and Cys69) and holo (Lys6, Lys31, His43, Lys46, Lys57 and Cys69) L-FABP. The impact of 4-HNE adduction was found to occur in a concentration-dependent manner; affinity for the fluorescent ligand, anilinonaphthalene-8-sulfonic acid, was reduced from 0.347 µM to Kd(1) = 0.395 µM and Kd(2) = 34.20 µM. Saturation analyses revealed that capacity for ligand is reduced by approximately 50% when adducted by 4-HNE. Thermal stability curves of apo L-FABP was also found to be significantly affected by 4-HNE adduction (ΔTm = 5.44°C, PL-FABP while more apparent differences were observed within the internal binding pocket, revealing reduced area and structural integrity. New solvent accessible portals on the periphery of the protein were observed following 4-HNE modification in both the apo and holo state, suggesting an adaptive response to carbonylation. The results from this study detail the dynamic process associated with L-FABP modification by 4-HNE and provide insight as to how alterations in structural integrity and ligand binding may a contributing factor in the pathogenesis of ALD.

  9. Ocean acidification alters the otoliths of a pantropical fish species with implications for sensory function.

    Science.gov (United States)

    Bignami, Sean; Enochs, Ian C; Manzello, Derek P; Sponaugle, Su; Cowen, Robert K

    2013-04-30

    Ocean acidification affects a wide diversity of marine organisms and is of particular concern for vulnerable larval stages critical to population replenishment and connectivity. Whereas it is well known that ocean acidification will negatively affect a range of calcareous taxa, the study of fishes is more limited in both depth of understanding and diversity of study species. We used new 3D microcomputed tomography to conduct in situ analysis of the impact of ocean acidification on otolith (ear stone) size and density of larval cobia (Rachycentron canadum), a large, economically important, pantropical fish species that shares many life history traits with a diversity of high-value, tropical pelagic fishes. We show that 2,100 μatm partial pressure of carbon dioxide (pCO2) significantly increased not only otolith size (up to 49% greater volume and 58% greater relative mass) but also otolith density (6% higher). Estimated relative mass in 800 μatm pCO2 treatments was 14% greater, and there was a similar but nonsignificant trend for otolith size. Using a modeling approach, we demonstrate that these changes could affect auditory sensitivity including a ∼50% increase in hearing range at 2,100 μatm pCO2, which may alter the perception of auditory information by larval cobia in a high-CO2 ocean. Our results indicate that ocean acidification has a graded effect on cobia otoliths, with the potential to substantially influence the dispersal, survival, and recruitment of a pelagic fish species. These results have important implications for population maintenance/replenishment, connectivity, and conservation efforts for other valuable fish stocks that are already being deleteriously impacted by overfishing.