Protein tyrosine phosphatase is a classical non receptor tyrosine phosphotase enzyme and is an important regulator in several signaling pathways including insulin and leptin. PTP1B is a negative regulator of insulin receptor (IR) which dephosphorylates tyrosine residues of Insulin Receptor tyrosine Kinase (IRK) domain and induces resistance to insulin sensitivity and obesity up on over expressi...

Les problématiques posées par les intrants sous leurs diverses formes ont récemment bénéficié d’une plus large prise en compte, et d’un gain d’intérêt auprès du grand public des autorités compétentes. Cette demande sociétale se traduit une augmentation diversification solutions alternatives aux d’origine chimique, que ce soit avec produits de biocontrôle pour la protection plantes, fertilisatio...

Lipase from Pseudomonas cepacia was covalently immobilized on crystalline silicon, porous silicon and silicon nitride surfaces. The various stages of immobilization were characterized using FTIR (Fourier transform infrared) spectroscopy. The surface topography of the enzyme immobilized surfaces was investigated using scanning electron microscopy (SEM). The quantity of the immobilized active enz...

The principal cause of the clinical failure of bioprosthetic heart valves fabricated from glutaraldehyde-pretreated porcine aortic valves is calcification. Other prostheses composed of tissue-derived and polymeric biomaterials also are complicated by deposition of mineral. We have previously demonstrated that: (a) Failure due to calcification of clinical bioprosthetic valves can be simulated by...

The divalent metal ions, Mg2+ and Ca”, catalyze the reaction of p-nitrophenyl phosphate dianion (PNPP) with substituted pyridines but do not increase the associative character of the transition state, as indicated by values of p,,, in the range 0.17-0.21 for PNPP and for its metal ion complexes. The reactions of phosphorylated morpholinopyridine (MPP) are inhibited approximately twofold by Mg2+...

Lipases are the special kind of esterases belong to subclass 1 of hydrolytic enzyme class 3 and have been assigned subsub class 3.1.1 due to their specificity for carboxylic acid ester bonds. The biological function of lipase is to catalyze the hydrolysis of triacylglycerols to give free fatty acid, diacylglycerols, mono-acylglycerols and glycerol. They constitute the most important group of bi...

Vacuoles were prepared from endosperm tissue of 4-day-old castor bean seedlings (Ricinus communis var. Hale) and purified on a stepped sucrose gradient. It was shown by assays of marker enzymes that there was only trace contamination of the final preparation by other organeiles (mitochondria, glyoxysomes, nuclei, spherosomes, and plastids) and by cytoplasmic components. Hydrolytic enzymes (acid...

AIM To investigate the effects of extract from Fructus cannabis (EFC) that can activate calcineurin on learning and memory impairment induced by chemical drugs in mice. METHODS Bovine brain calcineurin and calmodulin were isolated from frozen tissues. The activity of calcineurin was assayed using p-nitrophenyl phosphate (PNPP) as the substrate. Step-down type passive avoidance test and water ...