77 research outputs found

    A Meta-Analysis for Understanding the Role of  the COMT Val158Met Variant in the Susceptibility to Alcoholism

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    The hypothesis of association between 158Met allele of catechol-o-methyltransferase (COMT) gene and poor dopamine catabolism, dopamine remains prolonged for their half-time in the prefrontal cortex and gets more reward from alcohol than COMT Val158 allele, has generated much interest, research and controversy. Hence, a meta-analysis to explore possible role of COMT Val158Met variant and alcoholism has been performed. Twenty-two case-control data sets containing 3602 alcoholism patients and 5183 healthy subjects genotyped for COMT Val158Met variant has been included and assessed for their association with alcoholism. Meta-analyses were conducted with the use of MetaGenyo web tool. The results of this study confirmed that the COMT Val158Met variant is not contributing to the risk of alcoholism (Dominant model: OR = 1.10 (95% CI = 0.92-1.30), I2 = 49%). Subgroup analysis by ethnicity also found no association of this allele with alcoholism risk in both Asian (Dominant model: OR = 1.15 (95% CI = 0.83-1.60), I2 = 43%) and Caucasian (Dominant model: OR = 1.07 (95% CI = 0.87-1.32), I2 = 54%) populations. The meta-analysis results of this study suggest no significant correlation between COMT Val158Met variant and alcoholism

    Compressive response of vertically aligned carbon nanotube films gleaned from in situ flat-punch indentations

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    We report the mechanical behavior of vertically aligned carbon nanotube films, grown on Si substrates using atmospheric pressure chemical vapor deposition, subjected to in situ large displacement (up to 70 μm) flat-punch indentations. We observed three distinct regimes in their indentation stress–strain curves: (i) a short elastic regime, followed by (ii) a sudden instability, which resulted in a substantial rapid displacement burst manifested by an instantaneous vertical shearing of the material directly underneath the indenter tip by as much as 30 μm, and (iii) a positively sloped plateau for displacements between 10 and 70 μm. In situ nanomechanical indentation experiments revealed that the shear strain was accommodated by an array of coiled carbon nanotube “microrollers,” providing a low-friction path for the vertical displacement. Mechanical response and concurrent deformation morphologies are discussed in the foam-like deformation framework with a particular emphasis on boundary conditions

    Uniaxial Tension of a Class of Compressible Solids With Plastic Non-Normality

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    Motivated by a model that qualitatively captured the response of vertically aligned carbon nanotube (VACNT) pillars in uniaxial compression, we consider the uniaxial tensile response of a class of compressible elastic-viscoplastic solids. In Hutchens et al. [“Analysis of Uniaxial Compression of Vertically Aligned Carbon Nanotubes,” J. Mech. Phys. Solids, 59, pp. 2227–2237 (2011), Erratum 60, 1753–1756 (2012)] an elastic viscoplastic constitutive relation with plastic compressibility, plastic non-normality, and a hardening-softening-hardening hardness function was used to model experimentally obtained uniaxial compression data of cylindrical VACNT micropillars. Complex deformation modes were found in uniaxial compression, which include a sequential buckling-like collapse of the type seen in experiments. These complex deformation modes led to the overall stress-strain signature of the pillar not being of the same form as the input material hardness function. A fundamental question that motivates exploring the deformation of this class of materials—both experimentally and theoretically—is how to extract the intrinsic material response from simple tests. In this study we explore the relation between the input material response and the overall stress strain behavior in uniaxial tension using the constitutive framework of Hutchens et al. A simple one-dimensional analysis reveals the types of instability modes to be expected. Dynamic, finite deformation finite element calculations are carried out to explore the dependence of diffuse necking, localized necking, and propagating band deformation modes on characteristics of the hardness function. Attention is devoted to uncovering implications for obtaining intrinsic material properties of complex hierarchical structures; for example, vertically aligned carbon nanotubes (VACNTs), from uniaxial tension experiments

    Local Relative Density Modulates Failure and Strength in Vertically Aligned Carbon Nanotubes

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    Micromechanical experiments, image analysis, and theoretical modeling revealed that local failure events and compressive stresses of vertically aligned carbon nanotubes (VACNTs) were uniquely linked to relative density gradients. Edge detection analysis of systematically obtained scanning electron micrographs was used to quantify a microstructural figure-of-merit related to relative local density along VACNT heights. Sequential bottom-to-top buckling and hardening in stress–strain response were observed in samples with smaller relative density at the bottom. When density gradient was insubstantial or reversed, bottom regions always buckled last, and a flat stress plateau was obtained. These findings were consistent with predictions of a 2D material model based on a viscoplastic solid with plastic non-normality and a hardening–softening–hardening plastic flow relation. The hardening slope in compression generated by the model was directly related to the stiffness gradient along the sample height, and hence to the local relative density. These results demonstrate that a microstructural figure-of-merit, the effective relative density, can be used to quantify and predict the mechanical response

    Insights into salt tolerance of mustard (Brassica juncea L. Czern & Coss): A metabolomics perspective

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    Salt stress is one of the key abiotic factor which leads to reduced global agricultural productions through negatively impacting the growth and development of crops. Indian mustard (Brassica juncea), the most important cruciferous crop with significant nutritional and medicinal values, is majorly affected by salt stress. In this study, we explored the global metabolomic response of two Indian mustard genotypes, CS 60 and CS 245–2–80–7 grown under salt stress for different time periods to unleash the role of differentially accumulated metabolites and relevant metabolic pathways involved in the salt tolerance mechanism. A total of 608 known compounds were detected from 4119 metabolites using DionexUltiMate® 3000 Ultra High-Performance Liquid Chromatographic System combined with “Q Exactive™ Plus Orbitrap™ Mass Spectrometer (UHPLC-MS/MS) analysis, from which 111 significantly altered metabolites in both genotypes were selected based on t-test and VIP score values. Using MetPa from MetaboAnalyst 5.0 platform, metabolic pathways with significant impact values were considered to be involved in the salt tolerance mechanism. Increased accumulation of metabolites and detected relevant pathways majorly regulating the anti-oxidant defense system gives CS 60, a high yielding variety, an edge against the genotype CS 245–2–80–7, which might be the chief tolerance mechanism to withstand salt stress

    Валидация опросника для оценки качества жизни пациентов с хронической приобретенной полинейропатией (Chronic Acquired Polyneuropathy – Patient Reported Index, CAP-PRI) в России

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    Background. Chronic inflammatory demyelinating polyneuropathy (CIDP) is the most common immune‑mediated polyneuropathy. CIDP is characterized by a long‑term progressive or recurrent course of the disease and the development of neurological deficits and disability, it is important to assess the quality of life of patients. The paper presents the results of the first and second steps of validation of the Chronic acquired polyneuropathy – Patient Reported Index (CAP‑PRI) questionnaire designed to assess quality of life in patients with immune‑mediated polyneuropathy.Aim. To develop the Russian version of the CAP‑PRI questionnaire.Materials and methods. 85 patients with CIDP (according to EAN / PNS 2021 criteria) were enrolled. At the first step we conducted linguocultural validation according to the standard protocol. Two Russian‑speaking professional translators in the field of medicine performed direct translation of the original English‑language questionnaire, and the back translation was performed by native speakers with a medical background. At the second step the psychometric parameters were evaluated.Results. The developed Russian version of the CAP‑PRI questionnaire demonstrated a high level of reliability, validity and sensitivity.Conclusion. The Russian version of the CAP‑PRI questionnaire is recommended for clinical practice and research. In addition, the relationship between improved quality of life and the reduction of neurological deficits, disability and fatigue (as assessed by the IRODS, NIS and FSS scales) has been shown.Введение. Хроническая воспалительная демиелинизирующая полинейропатия (ХВДП) – самая частая из иммуноопосредованных полинейропатий. Для ХВДП характерны многолетнее прогрессирующее или рецидивирующее течение, развитие неврологического дефицита и инвалидизации, в связи с чем важен мониторинг качества жизни пациентов. Представлены результаты 1‑го и 2‑го этапов валидации русскоязычной версии опросника Chronic Acquired Polyneuropathy – Patient Reported Index (CAP‑PRI) для оценки качества жизни у пациентов с иммуноопосредованными полинейропатиями.Цель исследования – проведение валидации опросника CAP‑PRI у пациентов с ХВДП с разработкой его русскоязычной версии.Материалы и методы. В исследование было включено 85 пациентов с ХВДП, диагностированной на основании критериев EAN / PNS 2021. На 1‑м этапе проведена лингвистическая валидация оригинальной англоязычной версии опросника согласно общепринятым рекомендациям: 2 русскоязычными профессиональными переводчиками в сфере медицины выполнен прямой перевод оригинальной англоязычной шкалы, обратный перевод осуществлен носителями языка с медицинским образованием. На 2‑м этапе валидации проводилось исследование психометрических показателей разработанного русскоязычного варианта.Результаты. Разработана русскоязычная версия опросника CAP‑PRI с высоким уровнем надежности, содержательной валидности и чувствительности.Заключение. Представленная официальная русскоязычная версия опросника для пациентов с хронической приобретенной полинейропатией (CAP‑PRI) рекомендована для отечественной клинической практики и научно‑исследовательской работы с целью оценки качества жизни пациентов. Дополнительно показана связь между улучшением качества жизни и уменьшением выраженности неврологического дефицита, степени инвалидизации и утомляемости (по результатам оценок по шкалам IRODS, NIS и FSS)

    Genomic copy number variation in Mus musculus.

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    BACKGROUND: Copy number variation is an important dimension of genetic diversity and has implications in development and disease. As an important model organism, the mouse is a prime candidate for copy number variant (CNV) characterization, but this has yet to be completed for a large sample size. Here we report CNV analysis of publicly available, high-density microarray data files for 351 mouse tail samples, including 290 mice that had not been characterized for CNVs previously. RESULTS: We found 9634 putative autosomal CNVs across the samples affecting 6.87% of the mouse reference genome. We find significant differences in the degree of CNV uniqueness (single sample occurrence) and the nature of CNV-gene overlap between wild-caught mice and classical laboratory strains. CNV-gene overlap was associated with lipid metabolism, pheromone response and olfaction compared to immunity, carbohydrate metabolism and amino-acid metabolism for wild-caught mice and classical laboratory strains, respectively. Using two subspecies of wild-caught Mus musculus, we identified putative CNVs unique to those subspecies and show this diversity is better captured by wild-derived laboratory strains than by the classical laboratory strains. A total of 9 genic copy number variable regions (CNVRs) were selected for experimental confirmation by droplet digital PCR (ddPCR). CONCLUSION: The analysis we present is a comprehensive, genome-wide analysis of CNVs in Mus musculus, which increases the number of known variants in the species and will accelerate the identification of novel variants in future studies

    Approaches in biotechnological applications of natural polymers

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    Natural polymers, such as gums and mucilage, are biocompatible, cheap, easily available and non-toxic materials of native origin. These polymers are increasingly preferred over synthetic materials for industrial applications due to their intrinsic properties, as well as they are considered alternative sources of raw materials since they present characteristics of sustainability, biodegradability and biosafety. As definition, gums and mucilages are polysaccharides or complex carbohydrates consisting of one or more monosaccharides or their derivatives linked in bewildering variety of linkages and structures. Natural gums are considered polysaccharides naturally occurring in varieties of plant seeds and exudates, tree or shrub exudates, seaweed extracts, fungi, bacteria, and animal sources. Water-soluble gums, also known as hydrocolloids, are considered exudates and are pathological products; therefore, they do not form a part of cell wall. On the other hand, mucilages are part of cell and physiological products. It is important to highlight that gums represent the largest amounts of polymer materials derived from plants. Gums have enormously large and broad applications in both food and non-food industries, being commonly used as thickening, binding, emulsifying, suspending, stabilizing agents and matrices for drug release in pharmaceutical and cosmetic industries. In the food industry, their gelling properties and the ability to mold edible films and coatings are extensively studied. The use of gums depends on the intrinsic properties that they provide, often at costs below those of synthetic polymers. For upgrading the value of gums, they are being processed into various forms, including the most recent nanomaterials, for various biotechnological applications. Thus, the main natural polymers including galactomannans, cellulose, chitin, agar, carrageenan, alginate, cashew gum, pectin and starch, in addition to the current researches about them are reviewed in this article.. }To the Conselho Nacional de Desenvolvimento Cientfíico e Tecnológico (CNPq) for fellowships (LCBBC and MGCC) and the Coordenação de Aperfeiçoamento de Pessoal de Nvíel Superior (CAPES) (PBSA). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and COMPETE 2020 (POCI-01-0145-FEDER-006684) (JAT)

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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