IHTC14-23079 TRANSPORT PROCESS STUDY IN SODIUM ALANATE HYDROGEN STORAGE SYSTEM DURING DESORPTION

ABSTRACT Transport processes in a sodium alanate hydrogen storage system during desorption are presented. The mathematical model, which considers heat conduction and convection, hydrogen flow governed by Blake-Kozeny law and the chemical kinetics, is solved using the COMSOL Multiphysics ® finite element software. The numerical simulation is used to present the time-space evolutions of the temperature, pressure and hydride concentration. The results are discussed for two cases: a finned storage system and a finless one. It is shown that the whole process occurring in the bed is governed and controlled by heat transfer from the heating fluid to the storage media and strengthened by axial heat transfer through the fins. The importance of the hydride bed thermal conductivity has also been evaluated. It was observed that the hydrogen discharge rate in a finless system can be improved if we find ways of increasing the thermal conductivity of the storage media. On the other hand, for a reservoir with fins, heat transfer is good enough that the discharge rate is limited by the kinetics

FMF Is Associated With a Wide Spectrum of MHC Class I- and Allied SpA Disorders but Not With Classical MHC Class II-Associated Autoimmune Disease: Insights From a Large Cohort Study

Objectives: To test the hypothesis that familial Mediterranean fever (FMF)-associated autoinflammation may exaggerate the tendency toward adaptive immunopathology or spondyloarthritis (SpA)-associated disorders including major histocompatibility complex (MHC) class I associated disorders but not classical MHC class II-associated disorders that exhibit transplacental autoimmunity including myasthenia gravis and pemphigus. Methods: Seven thousand seven hundred forty-seven FMF patients and 10,080 age- and sex-matched controls in the Clalit Health Services medical database were identified and compared in terms of prevalence of SpA-associated disorders. We also evaluated four classical and strong MHC class II-associated disorders, namely, pemphigus vulgaris, myasthenia gravis, sarcoidosis, and pernicious anemia, to ascertain whether such associations with SpA-spectrum disease were specific or merely reflected the non-specific consequences of innate immune system activation on driving divergent types of immunity. The diagnosis of FMF was based on the medical records and not genetically proven. Results: FMF showed a strong association with MHC class I-related diseases: odds ratio (OR) of 28.58 [95% confidence interval (95% CI), 6.93–117.87; p < 0.0001] for Behçet's disease, OR of 10.33 (95% CI, 4.09–26.09; p < 0.0001) for ankylosing spondylitis, and OR of 1.67 (95% CI, 1.19–2.33; p = 0.0029) for psoriasis. For weakly MHC class I-linked diseases, an OR of 3.76 (95% CI, 2.48–5.69; p < 0.0001) for Crohn's disease and OR of 2.64 (95% CI, 1.52–4.56; p = 0.0005) for ulcerative colitis were found. No association was found between FMF and the four MHC class II-associated autoimmune disorders. Conclusion: FMF patients are associated with increased risk of SpA-related disease diagnosis including MHC-I-opathies but not MHC-II-associated autoimmune diseases, suggesting that tissue-specific dysregulation of innate immunity share between FMF and SpA spectrum disorders may drive adaptive immune MHC class I-associated conditions

Association of Methylentetraydrofolate Reductase (MTHFR) 677 C > T gene polymorphism and homocysteine levels in psoriasis vulgaris patients from Malaysia: a case-control study

<p>Abstract</p> <p>Background</p> <p>The methylenetetrahydrofolate reductase (MTHFR) enzyme catalyzes the reduction of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate and methyl donors. The methyl donors are required for the conversion of homocysteine to methionine. Mutation of MTHFR 677 C > T disrupts its thermostability therefore leads to defective enzyme activities and dysregulation of homocysteine levels.</p> <p>Methods</p> <p>This case-control study (n = 367) was conducted to investigate the correlation of the MTHFR gene polymorphism [NM_005957] and psoriasis vulgaris amongst the Malaysian population. Overnight fasting blood samples were collected from a subgroup of consented psoriasis vulgaris patients and matched controls (n = 84) for the quantification of homocysteine, vitamin B₁₂and folic acid levels.</p> <p>Results</p> <p>There was no significant increase of the MTHFR 677 C > T mutation in patients with psoriasis vulgaris compared with controls (<it>χ</it>²= 0.733, p = 0.392). No significant association between homocysteine levels and MTHFR gene polymorphism in cases and controls were observed (F = 0.91, df = 3, 80, p = 0.44). However, homocysteine levels in cases were negatively correlated with vitamin B₁₂(r = -0.173) and folic acid (r = -0.345) levels. Vitamin B₁₂and folic acid levels in cases were also negatively correlated (r = -0.164).</p> <p>Conclusions</p> <p>Our results indicate that there was no significant association between the MTHFR gene polymorphism and psoriasis vulgaris in the Malaysian population. There was no significant increase of the plasma homocysteine level in the psoriasis patients compared to the controls.</p

Polymorphisms in MTHFR, MS and CBS Genes and Homocysteine Levels in a Pakistani Population

Background: Hyperhomocysteinemia (\u3e15 mol/L) is highly prevalent in South Asian populations including Pakistan. In order to investigate the genetic determinants of this condition, we studied 6 polymorphisms in genes of 3 enzymes--methylenetetrahydrofolate reductase (MTHFR, C677T, A1298C), methionine synthase (MS, A2756G), cystathionine-beta-synthase (CBS, T833C/844ins68, G919A) involved in homocysteine metabolism and investigated their interactions with nutritional and environmental factors in a Pakistani population. Methodology/Principal Findings: In a cross-sectional survey, 872 healthy adults (355 males and 517 females, age 18-60 years) were recruited from a low-income urban population in Karachi. Fasting venous blood was obtained and assessed for plasma/serum homocysteine, folate, vitamin B12, pyridoxal phosphate and blood lead. DNA was isolated and genotyping was performed by PCR-RFLP (restriction-fragment-length-polymorphism) based assays. The average changes in homocysteine levels for MTHFR 677CT and TT genotypes were positive [beta(SE beta), 2.01(0.63) and 16.19(1.8) mol/L, respectively]. Contrary to MTHFR C677T polymorphism, the average changes in plasma homocysteine levels for MS 2756AG and GG variants were negative [beta(SE beta), -0.56(0.58) and -0.83(0.99) mol/L, respectively]. The average change occurring for CBS 844ins68 heterozygous genotype (ancestral/insertion) was -1.88(0.81) mol/L. The combined effect of MTHFR C677T, MS A2756G and CBS 844ins68 genotypes for plasma homocysteine levels was additive (p valu

Folate during reproduction: the Canadian experience with folic acid fortification

Folate has received international attention regarding its role in the risk-reduction of birth defects, specifically neural tube defects (NTDs). In 1998, health officials in Canada, like the United States, mandated the addition of folic acid to white flour and select grain products to increase the folate intake of reproductive-aged women. Subsequent to this initiative there has been an increase in blood folate concentrations in Canada and a 50% reduction in NTDs. Many countries, including Korea, have not mandated folic acid fortification of their food supply. Reasons vary but often include concern over the masking of vitamin B12 deficiency, a belief that folate intakes among womenare adequate, low priority relative to other domestic issues, and the philosophy that individuals have the right not to consume supplemental folic acid if they so choose. Prior to folic acid fortification of the food supply in Canada, the folate intakes of women were low, and their blood folate concentrations while not sufficiently low to produce overt signs of folate deficiency (eg. anemia) were inconsistent with a level known to reduce the risk of an NTD-affected pregnancy. The purpose of this article is to describe the role of folate during the periconceptional period, pregnancy, and during lactation. The rationale for, and history of recommending folic acid-containing supplements during the periconceptional period and pregnancy is described as is folic acid fortification of the food supply. The impact of folic acid fortification in Canada is discussed, and unresolved issues associated with this policy described. While the incidence of NTDs in Canada pre-folic acid fortification were seemingly higherthan that of Korea today, blood folate levels of Korean women are strikingly similar. We will briefly explore these parallels in an attempt to understand whether folic acid fortification of the food supply in Korea might be worth consideratio

Genome-wide association identifies nine common variants associated with fasting proinsulin levels and provides new insights into the pathophysiology of type 2 diabetes.

OBJECTIVE: Proinsulin is a precursor of mature insulin and C-peptide. Higher circulating proinsulin levels are associated with impaired β-cell function, raised glucose levels, insulin resistance, and type 2 diabetes (T2D). Studies of the insulin processing pathway could provide new insights about T2D pathophysiology. RESEARCH DESIGN AND METHODS: We have conducted a meta-analysis of genome-wide association tests of ∼2.5 million genotyped or imputed single nucleotide polymorphisms (SNPs) and fasting proinsulin levels in 10,701 nondiabetic adults of European ancestry, with follow-up of 23 loci in up to 16,378 individuals, using additive genetic models adjusted for age, sex, fasting insulin, and study-specific covariates. RESULTS: Nine SNPs at eight loci were associated with proinsulin levels (P < 5 × 10(-8)). Two loci (LARP6 and SGSM2) have not been previously related to metabolic traits, one (MADD) has been associated with fasting glucose, one (PCSK1) has been implicated in obesity, and four (TCF7L2, SLC30A8, VPS13C/C2CD4A/B, and ARAP1, formerly CENTD2) increase T2D risk. The proinsulin-raising allele of ARAP1 was associated with a lower fasting glucose (P = 1.7 × 10(-4)), improved β-cell function (P = 1.1 × 10(-5)), and lower risk of T2D (odds ratio 0.88; P = 7.8 × 10(-6)). Notably, PCSK1 encodes the protein prohormone convertase 1/3, the first enzyme in the insulin processing pathway. A genotype score composed of the nine proinsulin-raising alleles was not associated with coronary disease in two large case-control datasets. CONCLUSIONS: We have identified nine genetic variants associated with fasting proinsulin. Our findings illuminate the biology underlying glucose homeostasis and T2D development in humans and argue against a direct role of proinsulin in coronary artery disease pathogenesis

Large-scale sequencing identifies multiple genes and rare variants associated with Crohn’s disease susceptibility

peer reviewe

Communauté de pratique virtuelle sur la consommation de substances et la sexualité : étude de besoins

Les hommes ayant des relations sexuelles avec d’autres hommes (HARSAH) peuvent vivre des situations de vulnérabilité au regard de la consommation de substances psychoactives (SPA) et de la santé sexuelle. Ils font face également à des barrières concernant l’accessibilité à des services adaptés, dues à des lacunes en matière de formation des intervenants et au manque d’intégration des services. Les communautés de pratique virtuelles (CPV) représentent une avenue prometteuse pour pallier ces lacunes.Cette étude repose sur un devis mixte et vise à identifier les besoins et les attentes des utilisateurs potentiels afin d’orienter le développement d’une CPV (InterseXion). Afin de répondre à cet objectif, 49 intervenants québécois en santé sexuelle ou en dépendance ont rempli un questionnaire en ligne portant sur leurs compétences perçues en santé sexuelle et en dépendance, leur intérêt au sujet de la CPV ainsi que les contenus jugés les plus utiles. De ce nombre, sept intervenants ont pris part à une entrevue individuelle visant à approfondir la compréhension de leurs besoins.Les résultats mettent en évidence que l’intervention intégrée, sur les plans de la sexualité et de la dépendance, constitue un besoin de formation prioritaire pour l’ensemble des intervenants. La CPV est considérée comme une stratégie pertinente afin de répondre à des besoins de développement des compétences et de collaboration. Les entrevues mettent en relief le potentiel de la plateforme pour favoriser la collaboration intersectorielle et l’interdisciplinarité, développer des attitudes adéquates pour mieux intervenir, connaître et développer les meilleures pratiques. Des outils pour mieux intervenir ainsi que des exemples de meilleures pratiques sont proposés afin de favoriser l’atteinte de ces objectifs. Les résultats sont mis en perspective quant à leur contribution au développement de la CPV. Cette démarche souligne la pertinence de mener des études de besoins similaires pour le développement d’autres CPV en dépendance.Men who have sex with men (MSM) may encounter situations which make them vulnerable regarding substances use (SU) and sexual health. Inadequate training of health professionals and lack of integrated health services result in access barriers for MSM. Virtual communities of practice (VCoP) may be a promising avenue to counteract these specific service barriers.This mixed methods study aims to identify the needs and expectations of potential users of a VCoP (InterseXion). Fourty-nine health professionals from the province of Quebec working in addiction and sexual health services completed an online survey about their perceived skills regarding SU and sexual health interventions, their interest about the VCoP and the content they would consider most useful. To get a better understanding the needs of the health professionals, seven health professionals from the sample participated in individual interviews.The results show that integrated interventions in addiction and sexual health are a prominent training need for health professionals. The VCoP is considered a relevant strategy to attend to knowledge and skill development and collaboration needs. Participants interviewed highlighted the VCoP’s potential in facilitating intersectoral and interdisciplinary collaboration, developing adequate attitudes to improve interventions, and learning about best practices. Participants suggest intervention tools and examples of best practices to reach these objectives. The results are presented in light of their contribution to the subsequent development of the VCoP InterseXion. Conducting similar needs assessment for the development of other VCoP in the field of addiction is recommended.Los hombres que tienen relaciones sexuales con otros hombres pueden vivir situaciones de vulnerabilidad con respecto al consumo de sustancias psicoactivas y a la salud sexual. Enfrentan también barreras en cuanto al acceso a servicios adaptados, debido a las lagunas que existen en materia de capacitación profesionales clínicos y de la falta de integración de los servicios. Las comunidades de práctica virtuales son una solución prometedora para paliar esas lagunas.Este estudio reposa reposa sobre una metodología mixta y tiene como objetivo identificar las necesidades y las expectativas de los usuarios potenciales para orientar el desarrollo de una comunidad de práctica virtual (InterseXion). Para responder a este objetivo, 49 profesionales quebequenses en salud sexual o en dependencia respondieron a un cuestionario en línea sobre la percepción que tenían de sus competencias en salud sexual y dependencia, su interés por la comunidad de práctica virtual y los contenidos que juzgaban más útiles. De los 49 participantes del cuestionario en línea, siete participaron en una entrevista individual destinada a profundizar la comprensión sus necesidades.Los resultados ponen en evidencia que la intervención integrada en los planos de la sexualidad y la dependencia constituye una necesidad de capacitación prioritaria para el conjunto de los profesionales de la salud sexual y la dependencia. La comunidad de práctica virtual es considerada como una estrategia pertinente para responder a las necesidades de desarrollo de competencias y de colaboración. Las entrevistas ponen de relieve el potencial de la plataforma para favorecer la colaboración intersectorial y la interdisciplinaridad, desarrollar aptitudes adecuadas para intervenir mejor, conocer y desarrollar mejores prácticas. Se proponen herramientas para intervenir mejor y ejemplos de mejores prácticas para favorecer la consecución de estos objetivos. Los resultados se ponen en perspectiva en cuanto a su contribución al desarrollo de la comunidad de práctica virtual. Este enfoque subraya la pertinencia de llevar a cabo estudios de necesidades similares para el desarrollo de otras comunidades de práctica virtual en dependencia