National Chemical Laboratory

About: National Chemical Laboratory is a facility organization based out in Pune, Maharashtra, India. It is known for research contribution in the topics: Catalysis & Enantioselective synthesis. The organization has 8891 authors who have published 14837 publications receiving 387600 citations.

Delineating solute-solvent interactions in binary mixtures of ionic liquids in molecular solvents and preferential solvation approach.

Abstract: The effect of solute−solvent and solvent−solvent interactions on the preferential solvation of solvatochromic indicators in binary mixtures of ionic liquids with molecular solvents has been investigated. The binary mixtures of the pyridinium-based ionic liquids 1-butylpyridinium tetrafluoroborate ([BP][BF4]), 1-butyl-3-methylpyridinium tetrafluoroborate ([3-MBP][BF4]), and 1-butyl-4-methylpyridinium tetrafluoroborate ([4-MBP][BF4]) with molecular solvents like water, methanol, and dichloromethane have been selected for this investigation. The effect of addition of ionic liquids to molecular solvents on the polarity parameters ETN, Kamlet−Taft parameters, hydrogen bond donor ability (HBD) (α), hydrogen bond acceptor ability (HBA) (β), and polarizability (π*) was obtained. The polarity parameters of the mixture display nonideality on addition of ionic liquids to water and dichloromethane. On the other hand, strong synergetic effects were seen in the ionic liquid−methanol binary mixtures. The preferential so...

TGF-beta expression in renal transplant biopsies: a comparative study between cyclosporin-A and tacrolimus.

Abstract: BACKGROUND Chronic rejection is a major cause of graft dysfunction after kidney transplantation. This fibroproliferative disease may be promoted by overproduction of transforming growth factor beta (TGF-beta). Previous studies have suggested that CsA might increase production of this growth factor. The current study was designed to measure the expression of TGF-beta(b) in renal transplant biopsy specimens from patients undergoing immunosuppressive therapy with either CsA or tacrolimus (FK506). METHOD Paraffin-embedded renal biopsy specimens were sectioned, dewaxed, and incubated with primary antibody against TGF-beta(b)1 latency-associated protein and active TGF-beta(b1). After washing, the sections were treated with secondary antibody conjugated with FITC. In each case, the sections were assessed by semi-quantitative scanning laser confocal microscopic method. RESULTS There was no significant difference in latent TGF-beta(b) expression between biopsy specimens from patients receiving CsA and patients receiving FK506. However, biopsy specimens from patients receiving CsA expressed significantly more active TGF-beta(b1) than biopsy specimens from patients receiving FK506 (P<0.0001, Mann-Whitney test). DISCUSSION The increased level of active TGF-beta1 expression in renal biopsy specimens of patients receiving CsA may indicate a mechanism of chronic rejection. However, these biopsies were performed to assess deranged renal function; therefore, the specimens may reflect events rather than differences in medication.

“Clickable” SBA-15 mesoporous materials: synthesis, characterization and their reaction with alkynes

Abstract: SBA-15 mesoporous silica has been functionalized with azidopropyl groups through both one-pot co-condensation and post-synthetic grafting. For both these methodologies, azidopropyltriethoxysilane was used to introduce the azidopropyl groups. The azidopropyl modified SBA-15 material synthesized by one-pot co-condensation had hexagonal crystallographic order, pore diameters up of 50 A, and the content of azidopropyl groups was found to be 1.3 mmol g−1. The presence of the azidopropyl group was confirmed by multinuclear (13C, 29Si) solid state NMR and IR spectroscopy. Both these materials underwent very efficient Cu(I)-catalyzed azide alkyne “click” reaction (CuAAC) with a variety of alkynes. Nearly 85% of the azide present in the SBA-15 material was converted to the corresponding triazole when propargyl alcohol was used as the substrate. This methodology was also used to incorporate mannose into SBA-15. Incubation of this mannose labeled SBA-15 with fluorescein labeled Concanavalin-A led to the formation of a fluorescent silica-protein hybrid material. The ease of synthesis for the azide labeled SBA-15 material together with its ability to undergo very efficient chemoselective CuAAC in water would make it a very attractive platform for the development of covalently anchored catalysts, enzymes and sensors.

Potential Dual Role of Eugenol in Inhibiting Advanced Glycation End Products in Diabetes: Proteomic and Mechanistic Insights

Abstract: Medicinally important genus Ocimum harbors a vast pool of chemically diverse metabolites. Current study aims at identifying anti-diabetic candidate compounds from Ocimum species. Major metabolites in O. kilimandscharicum, O. tenuiflorum, O. gratissimum were purified, characterized and evaluated for anti-glycation activity. In vitro inhibition of advanced glycation end products (AGEs) by eugenol was found to be highest. Preliminary biophysical analysis and blind docking studies to understand eugenol-albumin interaction indicated eugenol to possess strong binding affinity for surface exposed lysines. However, binding of eugenol to bovine serum albumin (BSA) did not result in significant change in secondary structure of protein. In vivo diabetic mice model studies with eugenol showed reduction in blood glucose levels by 38% likely due to inhibition of α-glucosidase while insulin and glycated hemoglobin levels remain unchanged. Western blotting using anti-AGE antibody and mass spectrometry detected notably fewer AGE modified peptides upon eugenol treatment both in vivo and in vitro. Histopathological examination revealed comparatively lesser lesions in eugenol-treated mice. Thus, we propose eugenol has dual mode of action in combating diabetes; it lowers blood glucose by inhibiting α-glucosidase and prevents AGE formation by binding to e-amine group on lysine, protecting it from glycation, offering potential use in diabetic management.