Silicon Oxycarbide Aerogels for High-Temperature Thermal Insulation

This work has shown that the use of SOC-A35 leads to aerogel materials containing a significant concentration of carbidic species and limited amorphous free carbon. Substitution of the divalent oxide species in silica with tetravalent carbidic carbon has directly led to materials that exhibit increased network viscosity, reduced sintering, and limited densification. The SiOC aerogels produced in this work have the highest carbide content of any dense or porous SiOC glass reported in the literature at that time, and exhibit tremendous long-term thermal stability

Mechanism of action of L-arginine on the vitality of spermatozoa is primarily through increased biosynthesis of nitric oxide

The ability of sperm to fertilize the egg is primarily dependent on sperm motility and membrane integrity. Nitric oxide (NO) plays a decisive role in regulating multiple functions within the male reproductive system. The aim of the present study is to determine the mechanism by which L-arginine confers a protective action on spermatozoa obtained from the goat epididymis. NO is synthesized from L-arginine by the enzyme nitric oxide-synthase (NOS) present in spermatozoa. A possible participation of NO and NOS in arginine action has been suggested

Novel thermoresponsive assemblies of co-grafted natural and synthetic polymers for water purification

Water contamination and its purification are a global problem. The current approach to purify water is reduction of impurities to acceptable levels. One of the ways to achieve this is by use of water-soluble polymers that extract organic and metallic contaminants, from water. This paper presents a blend of composite polymers that eliminates both the contaminants simultaneously by the principle of adsorption at lower critical solution temperature. These composite polymers have been synthesized by grafting poly(N,N-diethylacrylamide), poly(N-isopropylacrylamide) and poly(N-vinylcaprolactam) on-to the natural polymer chitosan or its derivatives, giving smart graft polymeric assemblies (GPAs). One of the graft polymers, GPA-2, exhibits excellent adsorption properties able to remove metal ions like cadmium, cobalt, copper, lead, iron and also organic impurities like chlorophenol and phthalic anhydride. Studies reveal that 6 mg/ml GPA-2 is able to effect a 100% removal of organic impurities – chlorophenol (50 ppm) and phthalic anhydride (70 ppm) – from water, while complete removal of the heavy metal ions (Cu+2, Co+2 and Cd+2) together at 30 ppm concentration has been achieved with 7.5 mg/ml GPA-2. The reduction in level of impurities along with recyclability and reproducibility in the elimination spectrum makes these assemblies promising materials in water treatment.</jats:p

Interaction of artesunate with β-cyclodextrin: Characterization, thermodynamic parameters, molecular modeling, effect of PEG on complexation and antimalarial activity

AbstractInclusion of artesunate in the cavity of β-cyclodextrin (β-CD) as well as its methyl and hydroxypropyl derivatives was investigated experimentally and by molecular modeling studies. The effect of PEG on the inclusion was also studied. A 1:1 stoichiometry was indicated by phase-solubility studies both in the presence and absence of PEG and suggested by the mass spectrometry. The mode of inclusion was supported by 2D NMR and results were further verified by docking studies utilizing Fast Rigid Exhaustive Docking acronym. The thermodynamic parameters were determined for both binary and ternary systems using solution calorimetry and were found to be best for the methyl-β-cyclodextrin (Me-β-CD) system. However, the presence of PEG improves the complexation ability as evident from elevation in the numerical value of the stability constant (K). Solubility and dissolution profile of binary complex is enhanced in the presence of PEG, which is approximately at par with drug Me-β-CD complexes. In vivo studies showed 100% survivability in artesunate–Me-β-CD complexes

Connexin 43 mimetic peptide Gap27 reveals potential differences in the role of Cx43 in wound repair between diabetic and non-diabetic cells

During early wound healing (WH) events Connexin 43 (Cx43) is down-regulated at wound margins. In chronic wound margins, including diabetic wounds, Cx43 expression is enhanced suggesting that down-regulation is important for WH. We previously reported that the Cx43 mimetic peptide Gap27 blocks Cx43 mediated intercellular communication and promotes skin cell migration of infant cells in vitro. In the present work we further investigated the molecular mechanism of Gap27 action and its therapeutic potential to improve WH in skin tissue and diabetic and non-diabetic cells. Ex vivo skin, organotypic models and human keratinocytes/fibroblasts of young and old donors and of diabetic and non-diabetic origin were used to assess the impact of Gap27 on cell migration, proliferation, Cx43 expression, localization, phosphorylation and hemichannel function. Exposure of ex vivo WH models to Gap27 decreased dye spread, accelerated WH and elevated cell proliferation. In non-diabetic cell cultures Gap27 decreased dye uptake through Cx hemichannels and after scratch wounding cells showed enhanced migration and proliferation. Cells of diabetic origin were less susceptible to Gap27 during early passages. In late passages these cells showed responses comparable to non-diabetic cells. The cause of the discrepancy between diabetic and non-diabetic cells correlated with decreased Cx hemichannel activity in diabetic cells but excluded differences in Cx43 expression, localization and Ser368-phosphorylation. These data emphasize the importance of Cx43 in WH and support the concept that Gap27 could be a beneficial therapeutic to accelerate normal WH. However, its use in diabetic WH may be restricted and our results highlight differences in the role of Cx43 in skin cells of different origin

Income inequality and mental illness-related morbidity and resilience: a systematic review and meta-analysis

Background Studies of the association between income inequality and mental health have shown mixed results, probably due to methodological heterogeneity. By dealing with such heterogeneity through a systematic review and meta-analysis, we examine the association between income inequality, mental health problems, use of mental health services, and resilience (defined as the ability to cope with adversity). Methods We searched the Global Health, PsychARTICLES, PsycINFO, Social Policy and Practice, Embase and MEDLINE databases up to July 6, 2016, for quantitative studies of the association of income inequality with prevalence or incidence of mental disorders or mental health problems, use of mental health services, and resilience. Eligible studies used standardised instruments at the individual level, and income inequality at the aggregated, contextual, and ecological level. We extracted study characteristics, sampling, exposure, outcomes, statistical modelling, and parameters from articles. Because several studies did not provide enough statistical information to be included in a meta-analysis, we did a narrative synthesis to summarise results with studies categorised as showing either a positive association, mixed results, or no association. The primary outcome in the random-effects meta-analysis was mental health-related morbidity, defined as the prevalence or incidence of any mental health problem. This study is registered with PROSPERO, number CRD42016036377. Findings Our search identified 15 615 non-duplicate references, of which 113 were deemed potentially relevant and were assessed for eligibility, leading to the inclusion of 27 studies in the qualitative synthesis. Nine articles found a positive association between income inequality and the prevalence or incidence of mental health problems; ten articles found mixed results, with positive association in some subgroups and non-significant or negative association in other subgroups; and eight articles found no association between income inequality and mental health problems. Of the nine articles included in our meta-analysis, one reported a positive association between income inequality and mental health problems, six reported mixed results, and two reported no association. Pooled Cohen's d effect sizes for the association between income inequality and any mental disorder or mental health problems were 0·06 (95% CI 0·01–0·11) for any mental disorder, and 0·12 (0·05–0·20) for depressive disorders. Our meta-regression analysis showed that none of the factors considered (sample size, contextual level at which income inequality was assessed, quality assessment, type of instruments, and individual income as control variable) explained heterogeneity between studies (I2 89·3%; p<0·0001). Only one study investigated the association between income inequality and resilience; it found greater income inequality was associated with higher prevalence of depression only among individuals with low income. The only study of the role of income inequality as a determinant of the use of mental health services reported no association. Interpretation Income inequality negatively affects mental health but the effect sizes are small and there is marked heterogeneity among studies. If this association is causal and growing income inequality does lead to an increase in the prevalence of mental health problems, then its reduction could result in a significant improvement in population wellbeing

Can Admission and Fasting Glucose Reliably Identify Undiagnosed Diabetes in Patients With Acute Coronary Syndrome?

OBJECTIVE—Our objectives were to determine the prevalence of previously undiagnosed abnormal glucose tolerance, i.e., diabetes and impaired glucose tolerance (IGT) in patients with acute coronary syndrome and to assess the utility of admission and fasting glucose in identifying diabetes in these patients