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An efficient catalytic system employing TMS•OTf for the regioselective thiolation of electron‐rich arenes with sulfonyl hydrazides has been developed. The reaction occurs in a solvent mixture of dichloroethane and trifluoroethanol under mild conditions, with the addition of water. This method furnishes a range of para‐thio‐substituted arenes and 3‐sulfenyl‐indoles in good to excellent yields, marking a significant advancement in organic synthesis. [ABSTRACT FROM AUTHOR]

The renin‐angiotensin system (RAS) is crucial for regulating and understanding the pathophysiology of hypertension. However, there has been little focus on the breakdown of the active peptide, angiotensin II (AngII). Given that animals lacking aminopeptidase A (APA) exhibit hypertension, it may be concluded that APA is a crucial enzyme in regulating blood pressure by breaking down AngII. It has been also seen that the elevated blood pressure in the spontaneously hypertensive rat (SHR) is caused by the activation of the RAS and a concurrent reduction in renal angiotensin‐converting enzyme (ACE) activity. The activity of APA is elevated at the beginning of pre‐eclampsia and decreases below the levels seen during a normal pregnancy as pre‐eclampsia progresses (particularly, in severe cases). The activity of Serum APA is also heightened after hormone replacement treatment (HRT), perhaps as a response to increasing levels of AngII. Therefore, it is crucial to examine the connection between the activation of the RAS, the levels of AngII in the bloodstream, and the presence of APA in hypertension conditions. Summary: Aminopeptidase A (APA) plays a critical role in the regulation of blood pressure by modulating the renin‐angiotensin system. Inhibiting APA offers a novel therapeutic approach to reducing hypertension, particularly, in cases resistant to conventional treatments. This systematic review highlights the growing evidence supporting APA as a promising target for effective hypertension management. [ABSTRACT FROM AUTHOR]

Introduction: Phosphatidylethanol (PEth) is a long‐term marker of alcohol consumption used frequently in clinical scenarios such as liver transplant evaluation. Recent cases have demonstrated that packed red blood cell (pRBC) transfusion creates the potential for artificial elevation or decrease of observed PEth concentrations in recipients. Very little is known about the prevalence or stability of PEth in pRBCs. Methods: Apheresis and whole‐blood (WB) donations were tested for PEth using liquid chromatography – tandem mass spectrometry with limit of quantitation 10 ng/mL. Units were stored under routine blood bank conditions to evaluate the stability of PEth and the impact of irradiation. Results: Over 40% of apheresis and WB donors had PEth ≥10 ng/mL (maximum observed 587 ng/mL). As WB units were processed into component pRBCs, PEth concentrations increased and were higher than donor WB levels (EDTA sample) prior to collection (maximum observed 711 ng/mL). Storage for up to 5 weeks post donation resulted in mean 17.3% decrease in PEth‐positive units; in contrast to a prior report, we observed no PEth formation in units with negative (<10 ng/mL) baseline concentrations. Irradiation of pRBCs did not substantially affect PEth concentrations in either PEth‐positive or PEth‐negative units. Discussion: PEth concentrations in healthy blood donors may potentially confound alcohol use or abstinence assessment in pRBC recipients. Transfusion medicine services and clinical practices such as transplantation and behavioral medicine should recognize this phenomenon and collaborate on testing protocols to appropriately interpret PEth in pRBC recipients. [ABSTRACT FROM AUTHOR]

In the current investigation, enhancement in the mechanical properties, thermal stability, and decrement in the moisture absorption capabilities of polyvinyl alcohol was observed by cross‐linking it with different weight percentages (wt. %) of fumaric acid and reinforcing them along with sulfuric acid‐modified graphite particles. The effects of altering the cross‐linking duration and fumaric acid wt. % were investigated in the resulting composite using the Taguchi L16 experimental design method. As in this contemporary era of rapid industrial expansion and fierce competition, the primary goals of manufacturers revolve around the production of high‐quality goods at optimal costs within a specified timeframe. Therefore, to save both cost and time, the authors have utilized a technique known as "gray‐fuzzy optimization" to balance competing goals between mechanical (toughness, elongation and strength) and physical (water intake capacity) attributes. The present approach aimed to reduce the experimentation expenses and increase the effectiveness of composite manufacturing by considerably reducing the intricacy of practical multi‐response optimization issues. Response graphs and analysis of variance tests were also utilized to calculate the percentage contribution of the input variables and provide model significance. Highlights: Polyvinyl alcohol is cross‐linked with different weight percentages (wt. %) of fumaric acid, and reinforced them with sulfuric acid‐modified graphite particles.Enhancement in mechanical properties, thermal stability, and decrease in moisture absorption capabilities were perceived for the fabricated composite.Effects of altering the cross‐linking duration and fumaric acid wt. % were investigated in the resulting composite using the Taguchi L16 experimental design.Gray‐fuzzy optimization technique was utilized to balance competing goals between water intake and mechanical attributes like toughness, elongation and strength.Response graphs and analysis of variance (ANOVA) tests were also utilized to evaluate the percentage contribution of input variables and provide model significance. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) is a widely used polymer that is biocompatible, nontoxic, and water‐soluble due to the presence of hydroxyl groups in its domain. This study aims to investigate the effects of fumaric acid (FA) cross‐linking and thermal cross‐linking (TC) on the PVA's mechanical and thermal properties. When the FA is mixed with PVA, it was found in the chemical reaction that the OH groups of PVA are condensing with the carboxylic acid units of FA to yield new ester linkages and water as a by‐product, which further results in the reduction of the water absorption capacity. Quantitatively, the addition of 8 (wt. /wt. %) FA resulted in a minimum of 65% water absorption rate, as compared with 117% for pure PVA. The mechanical and thermal properties of PVA also enhanced with the addition of 2% to 8% FA by weight. For the TC case, the % increase in ultimate tensile strength was 30.9% and 42.5% with and without TC, respectively. As the wt. % of FA increased from 2 to 10%, the % elongation value decreased for both with and without TC films relative to pure PVA. The thermogravimetric analysis revealed the change in degradation temperature of FA‐PVA blended film in comparison with pure PVA. Dynamic mechanical analysis was utilized to analyze the viscoelastic nature and temperature variation at the glass transition temperature. The current fabricated film is a potential candidate for the food packaging films application; moreover, the results reported in this investigation will accelerate the industrial applications of biodegradable PVA. Highlights: Increasing the weight percentage of fumaric acid leads to an enhancement in mechanical and thermal properties of the film.Esterification is the usual reaction between fumaric acid and polyvinyl alcohol (PVA), in which ester linkages are formed when the carboxyl groups (‐COOH) of fumaric acid and the hydroxyl groups (‐OH) of PVA combine.Water absorption characteristics of the film reduces as the wt. % of fumaric acid increases.Thermal cross‐linking of the film leads to further improvements in mechanical and thermal properties.The overall effect of increasing the wt. % of fumaric acid is negative on the glass transition temperature of the film.The developed film is a potential candidate for the food packaging films application. [ABSTRACT FROM AUTHOR]

Malate (2‐hydroxysuccinic acid) and tartrate (2,3‐dihydroxysuccinic acid) are chiral substrates; the former existing in two enantiomeric forms (R and S) while the latter exists as three stereoisomers (R,R; S,S; and R,S). Dehydration by stereospecific hydrogen abstraction and antielimination of the hydroxyl group yield the achiral products fumarate and oxaloacetate, respectively. Class‐I fumarate hydratase (FH) and L‐tartrate dehydratase (L‐TTD) are two highly conserved enzymes belonging to the iron–sulfur cluster hydrolyase family of enzymes that catalyze reactions on specific stereoisomers of malate and tartrate. FH from Methanocaldococcus jannaschii accepts only (S)‐malate and (S,S)‐tartrate as substrates while the structurally similar L‐TTD from Escherichia coli accepts only (R)‐malate and (R,R)‐tartrate as substrates. Phylogenetic analysis reveals a common evolutionary origin of L‐TTDs and two‐subunit archaeal FHs suggesting a divergence during evolution that may have led to the switch in substrate stereospecificity preference. Due to the high conservation of their sequences, a molecular basis for switch in stereospecificity is not evident from analysis of crystal structures of FH and predicted structure of L‐TTD. The switch in enantiomer preference may be rationalized by invoking conformational plasticity of the amino acids interacting with the substrate, together with substrate reorientation and conformer selection about the C2C3 bond of the dicarboxylic acid substrates. Although classical models of enzyme–substrate binding are insufficient to explain such a phenomenon, the enantiomer superposition model suggests that a minor reorientation in the active site residues could lead to the switch in substrate stereospecificity. [ABSTRACT FROM AUTHOR]

A three‐component, solvent‐dependent, Brønsted‐acid‐catalyzed reaction of benzaldehydes, silyl enolates and arene nucleophiles has been developed for the synthesis of potential drug candidate 3‐aryl‐1‐indanones. This reaction features the formation of three C−C bonds, high regioselectivity in a one‐pot strategy, broad substrate generality, facile scalability (1.04g), high functional group tolerance and viable substrates. The β‐O‐silyl ethers generated in‐situ from the Mukaiyama aldol reaction were subjected to acid‐catalyzed benzylic arylation with strong as well as weak nucleophiles, and the resultant β,β‐diaryl esters can undergo a third C−C bond formation with excellent regioselectivity through intramolecular cyclization to afford the indanone products in the same pot. Detailed mechanistic insight leads to a feasible reaction pathway. This transformation opens up a practical and adaptable approach to producing a variety of synthetically valuable transformations and enable the synthesis of medicinally valuable (R)‐tolterodine and (+)‐indatraline. [ABSTRACT FROM AUTHOR]

This work describes a mild and robust double hydroarylation strategy for the synthesis of symmetrical /unsymmetrical diaryl‐ and triarylmethanes in excellent yields using Lambert salt (0.2–1.0 mol%). Despite the anticipated challenges associated with controlling selective product formation, unsymmetrical diaryl‐ and triarylmethanes products are obtained unprecedentedly. A highly efficient gram scale reaction has also been reported (TON for symmetrical product=475 and for unsymmetrical product=390). The synthetic utility of the methodology is demonstrated by the preparation of several unexplored diaryl‐ and triarylmethane‐based biologically relevant molecules, such as arundine, vibrindole A, turbomycin B, and certain anti‐inflammatory agents. A total synthesis of an anti‐breast‐cancer agent is also demonstrated. Control experiments, Hammett analysis, HRMS and GC‐MS studies reveal the reaction intermediates and reaction mechanism. [ABSTRACT FROM AUTHOR]

Background. Hypothyroidism is a highly prevalent and multifactorial disorder and has been implicated in the causation of dyslipidemia, dermatological diseases, atherosclerosis, and myocardial dysfunction, as well as endothelial dysfunction. The relationship between subclinical hypothyroidism and type 2 diabetes mellitus is not well established. In the present study, we attempt to find out the prevalence of subclinical hypothyroidism in type 2 diabetes mellitus and its association with glycemic control. Materials and Methods. This was an observational study in which 205 consecutive patients of T2DM visiting the outpatient department of medicine were recruited. Serum TSH, free thyroxine, free triiodothyronine, and lipid profile, as well as HbA1c assays, were done in the study participants, and they were categorized into three groups by HbA1c: <7%, 7–9%, and >9%. Results. There is a high prevalence of subclinical hypothyroidism in type 2 DM patients. Mean HbA1c in diabetics without SCH was 7.89%, whereas it was 8.33% in diabetics with SCH. This difference was statistically not significant. TSH was not found to be significantly associated with HbA1c. Conclusion. High prevalence of SCH in T2DM patients suggests that there is a need for regular follow-up to check the progression of SCH to overt hypothyroidism. High serum TSH is not a predictor of poor glycemic control. [ABSTRACT FROM AUTHOR]

Background and Aim: While the prevalence of celiac disease (CD) is increasing globally, the prevalence of tropical sprue (TS) is declining. Still, there are certain regions in the world where both patients with CD and TS exist and differentiation between them is a challenging task. We conducted a systematic review of the literature to find out differentiating clinical, endoscopic, and histological characteristics between CD and TS. Methods: Medline, PubMed, and EMBASE databases were searched for keywords: celiac disease, coeliac, celiac, tropical sprue, sprue, clinical presentation, endoscopy, and histology. Studies published between August 1960 and January 2018 were reviewed. Out of 1063 articles available, 12 articles were included in the final analysis. Results: Between the patients with CD and TS, there was no difference in the prevalence and duration of chronic diarrhea, abdominal distension, weight loss, extent of abnormal fecal fat content, and density of intestinal inflammation. The following features were more common in CD: short stature, vomiting/dyspepsia, endoscopic scalloping/attenuation of duodenal folds, histological high modified Marsh changes, crescendo type of IELosis, surface epithelial denudation, surface mucosal flattening, thickening of subepithelial basement membrane and celiac seropositivity; while those in TS include anemia, abnormal urinary D‐xylose test, endoscopic either normal duodenal folds or mild attenuation, histologically decrescendo type of IELosis, low modified Marsh changes, patchy mucosal changes, and mucosal eosinophilia. Conclusions: Both patients with CD and TS have overlapping clinical, endoscopic, and histological characteristics, and there is no single diagnostic feature for differentiating CD from TS except for celiac specific serological tests. [ABSTRACT FROM AUTHOR]

Statin use is associated with increased calorie intake and consequent weight gain. It is speculated that statin-dependent improvements in lipid profile may undermine the perceived need to follow lipid-lowering and other dietary recommendations leading consequently to increased calorie intake. However, increases in calorie intake in statin users may also be related to statin-dependent decreases in satiety factors such as leptin, an adipocyte-derived adipokine. The objective of our study was to examine the direct effects of statins on leptin expression. Adipocytes are the main source of circulating leptin. Therefore, we examined the effects of atorvastatin and simvastatin on leptin expression in cultured human white adipocytes. We show that treatment of white adipocytes with simvastatin and atorvastatin decreases leptin mRNA expression (simvastatin: P = 0.008, atorvastatin: P = 0.03) and leptin secretion (simvastatin: P = 0.0001, atorvastatin: P = 0.0001). Both simvastatin and atorvastatin mediate decreases in leptin expression via extracellular-signal-regulated kinases 1/2 and peroxisome proliferator-activated receptor gamma pathways (simvastatin: P = 0.01, atorvastatin: P = 0.026). Additionally, statin treatment also induced expected increases in adiponectin, while decreasing monocyte chemoattractant protein 1 (MCP1) mRNA. Furthermore, statins increased secretion of both total as well as high molecular weight adiponectin while decreasing MCP1 secretion. To conclude, statins act directly on human white adipocytes to regulate adipokine secretion and decrease leptin expression. Leptin is an important satiety factor. Hence, statin-dependent decreases in leptin may contribute, at least in part, to increases in food intake in statin users. [ABSTRACT FROM AUTHOR]

This paper reports on the eco-friendly synthesis of gold nanoparticles (AuNPs) using Solanum indicum fruit extract (SFE). We have evaluated various parameters for synthesis of AuNPs such as SFE (0.03%), HAuCl4 (0.5 mM) and reaction time (20 seconds). The synthesized AuNPs were characterized with different physical techniques such as transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). TEM experiments showed that AuNPs presented an anisotropic shape and size ranging from 5-50nm. FT-IR spectroscopy revealed that biomolecules containing an amine group (-NH2), a carbonyl group, -OH groups and other stabilizing functional groups were adsorbed on the surface of the synthesized AuNPs. EDX showed the presence of the elements on the surface of the AuNPs. The cytotoxicity of the synthesized AuNPs were tested on two different human cancer cell lines, HeLa and MCF-7 and were found to be nontoxic, thus providing an opportunity to be used in biomedical applications. [ABSTRACT FROM AUTHOR]

Focuses on the molecular biology of the low-temperature response in plants. Relationship of plant's survival to temperature tolerance; Importance of designing strategies to improve cold tolerance in crop varieties for plant production and expansion of the area under cultivation; Tolerance of plants to environmental stress through physical adaptation.

Problems associated with mental health have increased tremendously in modern times. The search for effective and safe alternatives should, therefore, be persued vigourously. Forced immobilization is one of the best explored models of stress in rats and the role of corticosterone, serotonin (5-HT) and catecholamines, i.e. norepinephrine, epinephrine, dopamine is well documented. We investigated the therapeutic potential of two gold preparations (AyurvedicSwarna Bhasmaand UnaniKushta Tila Kalan) in restraint induced stress at different time points of 1 hr, 2 hr and 4 hr. We pretreated rats with two gold prepaprations, AyurvedicSwarna Bhasmaand UnaniKushta Tila Kalan(25 mg/kg, orally for 10 days) prior to restraint stress. Brain catecholamine, serotonin and plasma corticosterone levels were determined following 1, 2 and 4 hr restraint stress, using HPLC and also plasma corticosterone using luminescence spectrophotometry. Gold preparations restored restraint stress-induced elevation in levels of brain catecholamines (norepinephrine, epinephrine and dopmine), 5-HT and plasma corticosterone to near normal levels. Gold, widely used in modern medicine for the treatment of rheumatoid arthritis, is highly valued for various medicinal uses in Indian systems of medicine. Traditional gold preparations are attributed with tonic/rejuvenating and antioxidant properties. Our earlier studies revealed interesting analgesic, immunostimulant, adaptogenic and glycogen sparing properties in these preparations, but their effects in stress and depression have not been investigated yet. Significant restoration of altered values to near normal levels suggest potentials for gold preparations in stress and depression. [ABSTRACT FROM AUTHOR]

Evaluates the efficacy of Tiron and calcium disodium EDTA in the treatment of beryllium intoxication in rats. Protein and glycogen contents; Activity of alkaline phosphatase; Atomic adsorption spectrophotometry.