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The aqueous extract of cotton seed is able to reduce blood sugar in alloxan-induced diabetes mellitus in rats. A dose of 1000 mg/kg was found to be an effective dose. Cotton seed extract was able to enhance the liver glycogen, like glibenclamid, and was also able to reduce blood cholesterol which was found raised in the diabetic state. Further it was able to normalize the altered level in the liver lipid peroxide content. The role of cotton seed aqueous extract is suggested in the lipid metabolism which is altered during diabetes mellitus.  相似文献   
3.
Using rat hepatocytes we confirmed our previous results that glucagon and -adrenergic agonists increased the enzyme activity of alanine aminotransferase (AAT) and propranolol abolished their effects. Only the enzyme activity was measured and other parameters like quantity of the enzyme or activation due to modification were not looked for. As in perfusion experiment phenylephrine and phenoxybenzamine (-agonist and -antagonist respectively) also increased the AAT activity in isolated rat hepatocytes and propranolol reversed these effects. The additive effect of glucagon and phenoxybenzamine on AAT was also persistant in hepatocyte system.Fructose- 1:6-bisphosphatase (Fru-P2ase), another key enzyme in gluconeogenic pathway, was elevated by glucagon and other -adrenergic agonists both in liver perfusion and isolated hepatocyte experiments and was brought back to the normal level by propranolol. In this case also only the enzyme activity was measured and no other parameters were looked for. Unlike AAT this enzyme was not stimulated by phenylephrine or phenoxybenzamine. But AAT and Fru-P2-ase activities were increased significantly by adenylate cyclase activators like fluoride or forskolin. Thus, it appears that the regulation of fru-P2-ase by glucagon is purely a -receptor mediated process whereas AAT activation shows a mixed type of regulation where some well known -agonist and antagonists are behaving as -agonists.Results further indicate the presence of phosphodiesterase in hepatocyte membrane which was stimulated by glucagon and brought back to the normal level by propranolol.The different adrenergic compounds stated above, not only modified the activity of the above two enzymes but also stimulated glucose production by hepatocytes from alanine which was in turn abolished by propranolol as well as amino oxyacetate (AOA), a highly specified inhibitor of AAT. This confirm the participation of AAT in gluconeogenesis from alanine in liver. Forskolin and fluoride also increased the glucose production from alanine and showed additive effects with glucagon, phenylephrine and phenoxybenzamine.  相似文献   
4.
Summary Agglutination of washed rabbit erythrocytes caused by pancreatic acinar cell extract was inhibited by glucose, maltose and cellobiose. Process of elimination and purification divulged that the acinar cell enzyme -amylase was responsible for attributing the agglutinin activity. Assay of enzyme and agglutinin activity data of different fractions of re-purified -amylase eluted from HPLC column showed that both the activity resides in the same fraction which suggests that the enzyme binds to the glucosyl residues of the rabbit erythrocytes via the carbohydrate binding/catalytic sites. Similar properties of other glycosidases were also noted.  相似文献   
5.
In this study, we examined the mechanism of inhibition of phosphoserine phosphatase (PSPase) activity by elevated [Ca2+]i in insulin target cells. In in vitro studies, isolated rat adipocytes were incubated with either 40 mM K+ or parathyroid hormone (PTH) (20 ng/ml) for 1 h. In in vivo studies, rats were injected with PTH (three hourly injections of 40 micrograms intraperitoneally) prior to isolation of either adipocytes or skeletal muscle. Under these conditions, intracellular [Ca2+]i changed from 100 +/- 8.7 to 263 +/- 10.5 nM. There was a concomitant 30% decrease in adipocyte PSPase activity and a 35% decrease in skeletal muscle PSPase activity, assayed using 32P-labeled phosphorylase "a" as a substrate. The inhibition of PSPase was accompanied by a 60% increase in adipocytes (p less than 0.05) and a 118% increase (p less than 0.01) in skeletal muscle inhibitor 1 (I1) activities, respectively. Since I1 is active only in the phosphorylated state, we studied the effect of [Ca2+]i on I1 phosphorylation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of heat treated extracts immunoprecipitated with I1 antibody revealed significant increase in 32P incorporation (45-60%, p less than 0.05) into I1 protein in cells with elevated [Ca2+]i. Nitrendipine, a calcium channel blocker, completely prevented increases in I1 phosphorylation and activity in cells exposed to K+ but was only partially effective in the PTH-treated cells. In contrast, a cyclic AMP antagonist, RpcAMP, prevented both the K(+)-and the PTH-induced increases in I1 phosphorylation and activity, even though it failed to block the elevations in [Ca2+]i in these cells. We conclude that [Ca2+]i-induced and cAMP-mediated phosphorylation and activation of I1 results in inhibition of PSPase activity in insulin target cells. The inhibition of PSPases may cause inappropriate serine dephosphorylation of substrates of insulin action resulting in insulin resistance.  相似文献   
6.
Alzheimer''s Disease (AD) is one of the most common causes of dementia, mostly affecting the elderly population. Currently, there is no proper diagnostic tool or method available for the detection of AD. The present study used two distinct data sets of AD genes, which could be potential biomarkers in the diagnosis. The differentially expressed genes (DEGs) curated from both datasets were used for machine learning classification, tissue expression annotation and co-expression analysis. Further, CNPY3, GPR84, HIST1H2AB, HIST1H2AE, IFNAR1, LMO3, MYO18A, N4BP2L1, PML, SLC4A4, ST8SIA4, TLE1 and N4BP2L1 were identified as highly significant DEGs and exhibited co-expression with other query genes. Moreover, a tissue expression study found that these genes are also expressed in the brain tissue. In addition to the earlier studies for marker gene identification, we have considered a different set of machine learning classifiers to improve the accuracy rate from the analysis. Amongst all the six classification algorithms, J48 emerged as the best classifier, which could be used for differentiating healthy and diseased samples. SMO/SVM and Logit Boost further followed J48 to achieve the classification accuracy.  相似文献   
7.
Two locally-produced seasonal vegetables, carrot and patol, were preserved in brine, with and without radiation, with marked changes in their properties as foods and their microbiology. The treated vegetables could be preserved, at optimum salt and irradiation levels, for up to 60 days without becoming unacceptable in terms of appearance, texture, flavour and taste. The optimum salt concentrations for preservation of carrot and patol were 2% (w/v) and 3% (w/v), respectively. The microbial load initially showed an upward trend and then declined after 5 to 10 days of storage. Lactic acid bacteria predominated in treated vegetables.  相似文献   
8.
This study investigated the effects of dietary Bifidobacterium bifidum (BFD) and mannan-oligosaccharide (MOS), as a synbiotic, on the production performance, gut microbiology, serum biochemistry, antioxidant profile and health indices of broiler chicken. Six dietary treatments were T1 (negative control), T2 (positive control-20 mg antibiotic BMD kg−1 diet; BMD: bacitracin methylene disalicylate), T3 (0·1% MOS + 106 CFU BFD per g feed), T4 (0·1% MOS + 107 CFU BFD per g feed), T5 (0·2% MOS + 106 CFU BFD per g feed) and T6 (0·2% MOS + 107 CFU BFD per g feed). Significantly (P < 0·01) better growth performance and efficiency was observed in birds supplemented with 0·2% MOS along with 106 CFU BFD per g of feed compared to BMD and control birds. Supplementation with 0·2% MOS along with either 106 or 107 CFU BFD per g feed reduced (P < 0·01) the gut coliform, Escherichia coli, total plate count, and Clostridium perfringens count and increased the Lactobacillus and Bifidobacterium count. Significantly (P < 0·01) higher serum and liver antioxidant enzyme pool, serum HDL cholesterol and lower serum glucose, triglyceride, total cholesterol, cardiac risk ratio, atherogenic coefficient and atherogenic index of plasma were observed in birds supplemented with 0·2% MOS along with 106 CFU BFD per g of feed compared to control or BMD supplemented birds. Better production performance, gut microbial composition, serum biochemistry, antioxidant profile and health indices were depicted by broiler chicken supplemented with 0·2% MOS and 106 CFU BFD per g of feed.  相似文献   
9.
The ER‐bound kinase/endoribonuclease (RNase), inositol‐requiring enzyme‐1 (IRE1), regulates the phylogenetically most conserved arm of the unfolded protein response (UPR). However, the complex biology and pathology regulated by mammalian IRE1 cannot be fully explained by IRE1’s one known, specific RNA target, X box‐binding protein‐1 (XBP1) or the RNA substrates of IRE1‐dependent RNA degradation (RIDD) activity. Investigating other specific substrates of IRE1 kinase and RNase activities may illuminate how it performs these diverse functions in mammalian cells. We report that macrophage IRE1 plays an unprecedented role in regulating phosphatidylinositide‐derived signaling lipid metabolites and has profound impact on the downstream signaling mediated by the mammalian target of rapamycin (mTOR). This cross‐talk between UPR and mTOR pathways occurs through the unconventional maturation of microRNA (miR) 2137 by IRE1’s RNase activity. Furthermore, phosphatidylinositol (3,4,5) phosphate (PI(3,4,5)P3) 5‐phosphatase‐2 (INPPL1) is a direct target of miR‐2137, which controls PI(3,4,5)P3 levels in macrophages. The modulation of cellular PI(3,4,5)P3/PIP2 ratio and anabolic mTOR signaling by the IRE1‐induced miR‐2137 demonstrates how the ER can provide a critical input into cell growth decisions.  相似文献   
10.

Paenibacillus alvei NP75, a Gram-positive bacterium, produces two different antimicrobial peptides, paenibacillin N and P, which has potent antimicrobial activity against many clinical pathogens. The synthesis pattern of these antimicrobial peptides by P. alvei NP75 was studied extensively. The results were outstanding in a way that the paenibacillin N was synthesized irrespective of the growth of bacteria (non-ribosomal mediated), whereas paenibacillin P production was carried out by ribosomal mediated. In addition to the antimicrobial peptides, P. alvei NP75 also produces an immunogenic extracellular protease to defend itself from its own antimicrobial peptide, paenibacillin P. Furthermore, this immunogenic protease production was impaired by the addition of protease inhibitor, phenylmethylsulfonyl fluoride (PMSF). The sodium dodecyl sulfate (SDS) treated strain (mutant) failed to produce paenibacillin P, whereas the production of neither paenibacillin N nor the protease was affected by the plasmid curing. The plasmid curing studies that divulge the genes responsible for the synthesis of paenibacillin N and protease were found to be genome encoded, and paenibacillin P was plasmid encoded. We are reporting, first of its kind, the co-production of two different antimicrobial peptides from P. alvei NP75 through non-ribosomal and ribosomal pathways that could be used as effective antibiotics.

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