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81.
Tanveer Ahmad Wani Abdus Samad Monika Tandon Gurpreet S. Saini P. L. Sharma K. K. Pillai 《AAPS PharmSciTech》2010,11(1):425-432
In this open-label, balanced, randomized, placebo-controlled, parallel study, healthy male volunteers were randomly divided
into two groups. Each group received either a single oral dose of rosuvastatin 20 mg or placebo. Estimations were done at
predose on day 1 of dosing (baseline) and 24 h postdose after days 7 and 14. Serum cortisol and serum lipid levels were estimated
using enzyme-linked immunosorbent assay kits and serum mevalonic acid (MVA) levels were measured using validated liquid chromatography–tandem
mass spectrometry method. Rosuvastatin produced a statistically significant (P < 0.05) decrease in total cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and
triglycerides. However, the increase in high-density lipoprotein cholesterol and decrease in cortisol and MVA were not statistically
significant when compared to the placebo-treated group. The study showed that rosuvastatin at a dose of 20 mg/day for a period
of 14 days was very potent as cholesterol-lowering agent, without any significant change in serum cortisol level in the healthy
Indian male population. 相似文献
82.
83.
Roy S Khanna V Mittra S Dhar A Singh S Mahajan DC Priyadarsiny P Davis JA Sattigeri J Saini KS Bansal VS 《Life sciences》2007,81(1):72-79
Thiazolidinediones (TZDs) are currently the most efficacious class of oral antidiabetics. However, they carry the burden of weight gain and haemodilution, which may lead to cardiovascular complications. The present study was designed to ascertain whether a combination of dipeptidyl peptidase IV (DPP IV) inhibitor with low dose of a thiazolidinedione absolves TZD associated weight gain and oedema without compromising its efficacy. In this study, we examined the efficacy and safety of lower dose (1 mg/kg/day) of rosiglitazone, a thiazolidinedione, in combination with 5 mg/kg/day dose of LAF-237 (vildagliptin), a known DPP IV inhibitor, in aged db/db mice after 14 days of treatment and compared the combination with therapeutic dose (10 mg/kg) of rosiglitazone. The combination therapy showed similar efficacy as that of 10 mg/kg/day rosiglitazone in lowering random blood glucose (53.8%, p<0.001 and 54.3%, p<0.001 respectively), AUC ((0-120) min) during oral glucose tolerance test (OGTT) (38.6 %, p<0.01; 38.3%, p<0.01 respectively) and triglyceride levels (63.9% and 61% respectively; p<0.01). Plasma active glucagon like peptide-1 (GLP-1) and insulin levels were found to be elevated significantly (p<0.01 and p<0.05 respectively) in both LAF-237 and combination treated groups following oral glucose load. LAF-237 alone had no effect on random glucose and glucose excursion during OGTT in severely diabetic db/db mice. Interestingly, the combination treatment showed no significant increase in body weight as compared to the robust weight gain by therapeutic dose of rosiglitazone. Rosiglitazone at 10 mg/kg/day showed significant reduction (p<0.05) in haematocrit, RBC count, haemoglobin pointing towards haemodilution associated with increased mRNA expression of Na(+), K(+)-ATPase-alpha and epithelial sodium channel gamma (ENaCgamma) in kidney. The combination therapy escaped these adverse effects. The results suggest that combination of DPP IV inhibitor with low dose of thiazolidinedione can interact synergistically to represent a therapeutic advantage for the clinical treatment of type 2 diabetes without the adverse effects of haemodilution and weight gain associated with thiazolidinediones. 相似文献
84.
Human eosinophil-derived neurotoxin (EDN) or RNase 2, found in the non-core matrix of eosinophils is a ribonuclease belonging
to the Ribonuclease A superfamily. EDN manifests a number of bioactions including neurotoxic and antiviral activities, which
are dependent on its ribonuclease activity. The core of the catalytic site of EDN contains various base and phosphate-binding
subsites. Unlike many members of the RNase A superfamily, EDN contains an additional non-catalytic phosphate-binding subsite,
P−1. Although RNase A also contains a P−1 subsite, the composition of the site in EDN and RNase A is different. In the current study we have generated site-specific
mutants to study the role of P−1 subsite residues Arg36, Asn39, and Gln40 of EDN in its catalytic activity. The individual mutation of Arg36, Asn 39, and Gln40 resulted in a reduction in the catalytic activity of EDN on poly(U) and poly(C). However, there was no change in the activities
on yeast tRNA and dinucleotide substrates. The study shows that the P−1 subsite is crucial for the ribonucleolytic activity of EDN on polymeric RNA substrates.
Deepa Sikriwal and Divya Seth contributed equally to this work. 相似文献
85.
Sreejith P Beyo RS Divya L Vijayasree AS Manju M Oommen OV 《Indian journal of biochemistry & biophysics》2007,44(3):164-168
The effect of the hormones triiodothyronine (T3) and melatonin on antioxidant defense system was studied in 6-propyl thiouracil (6-PTU)-treated or photoperiod-exposed teleost Anabas testudineus. 6-PTU (2 microg/g) treatment or photoperiod exposure (24 h) increased malondialdehyde (MDA) and conjugated dienes (CD) concentrations, indicating increased lipid peroxidation (LPO) in the experimental conditions. T3 or melatonin (10(-6) M) treatment for 15 min in vitro in PTU-treated fish reversed the activity of superoxide dismutase (SOD), catalase and glutathione content. T3-treated group showed no change in glutathione peroxidase (GPx) activity, whereas melatonin treatment decreased its activity. T3 inhibited glutathione reductase (GR) activity. Photoperiod exposure (physiological pinealotomy) induced a stressful situation in this teleost, as evidenced by LPO products and antioxidant enzyme activities. Melatonin and T3 treatment for 15 min in vitro also reversed the effect of photoperiod on peroxidation products and the SOD and catalase activities. GR activity decreased in photoperiod-exposed group and melatonin and T3 treatment reversed the activities. The antioxidant enzymes responded to the stress situation after 6-PTU treatment and photoperiod exposure by altering their activities. The study suggested an independent effect of T3 and melatonin on antioxidant defence mechanism in different physiological situations in fish. 相似文献
86.
The Aer receptor guides Escherichia coli to specific oxygen and energy-generating niches. The input sensor in Aer is a flavin adenine dinucleotide-binding PAS domain, which is separated from a HAMP/signaling output domain by two membrane-spanning segments that flank a short (four-amino-acid) periplasmic loop. In this study, we determined the overall membrane organization of Aer by introducing combinations of residues that allowed us to differentiate intradimeric collisions from interdimeric collisions. Collisions between proximal residues in the membrane anchor were exclusively intra- or interdimeric but, with one exception, not both. Cross-linking profiles were consistent, with a rigid rather than flexible periplasmic loop and a tilted TM2 helix that crossed TM2' at residue V197C, near the center of the lipid bilayer. The periplasmic loop formed a stable neighborhood that (i) included a maximum of three Aer dimers, (ii) did not swap neighbors over time, and (iii) appeared to be constrained by interactions in the cytosolic signaling domain. 相似文献
87.
The aim of this work was to investigate the potential of water hyacinth (WH) spiked with cow dung (CD) into vermicompost. Five vermireactors containing WH and CD in different ratios, were run under laboratory conditions for 147 days. The maximum worm growth was recorded in CD alone. Worms grew and reproduced favourably in 25% WH+75% CD feed mixture. Greater proportion of WH in feed mixture significantly affected the biomass gain, hatchling numbers and numbers of cocoons produced during experiments. In all the vermireactors, there was significant decrease in pH, TOC and C:N ratio, but increase in TKN, TK and TAP at the end. The heavy metals content in the vermicomposts was lower than initial feed mixtures. The results indicated that WH could be potentially useful as raw substrate in vermicomposting if mixed with up to 25% in cow dung (on dry weight basis). 相似文献
88.
Shen HC Szymonifka MJ Kharbanda D Deng Q Carballo-Jane E Wu KK Wu TJ Cheng K Ren N Cai TQ Taggart AK Wang J Tong X Waters MG Hammond ML Tata JR Colletti SL 《Bioorganic & medicinal chemistry letters》2007,17(24):6723-6728
A urea class of high affinity niacin receptor agonists was discovered. Compound 1a displayed good PK, better in vivo efficacy in reducing FFA in mouse than niacin, and no vasodilation in a mouse model. Compound 1q demonstrated equal affinity to GPR109A as niacin. 相似文献
89.
Ten different strains of Thermomyces lanuginosus, isolated from composting soils were found to produce phytase when grown on PSM medium. The wild type strain CM was found to produce maximum amount ofphytase (4.33 units/g DW substrate). Culturing T. lanuginosus strain CM on medium containing wheat bran and optimizing other culture conditions (carbon source, media type, nitrogen source, level of nitrogen, temperature, pH, inoculum age, inoculum level and moisture), increased the phytase yield to 13.26 units/g substrate. This culture was further subjected to UV mutagenesis for developing phytase hyperproducing mutants. The mutant (TL-7) showed 2.29-fold increase in phytase activity as compared to the parental strain. Employing Box-Behnken factor factorial design of response surface methodology resulted in optimized phytase production (32.19 units/g of substrate) by mutant TL-7. A simple two-step purification (40.75-folds) ofphytase from mutant TL-7 was achieved by anion exchange and gel filtration chromatography. The purified phytase (approximately 54 kDa) was characterized to be optimally active at pH 5.0 and temperature 70 degrees C, though the enzyme showed approximately 70% activity over a wide pH and temperature range (2.0-10.0 and 30-90 degrees C, respectively). The phytase showed broad substrate specificity with activity against sodium phytate, ADP and riboflavin phosphate. The phytase from T. lanuginosus was thermoacidstable as it showed up to 70% residual activity after exposure to 70 degrees C at pH 3.0 for 120 min. The enzyme showed Km 4.55 microM and Vmax 0.833 microM/min/mg against sodium phytate as substrate. 相似文献
90.
Morphologically normal and fertile transgenic plants of mungbean with two transgenes, bar and α-amylase inhibitor, have been developed for the first time. Cotyledonary node explants were transformed by cocultivation
with Agrobacterium tumefaciens strain EHA105 harboring a binary vector pKSB that carried bialaphos resistance (bar) gene and Phaseolus vulgaris α-amylase inhibitor-1 (αAI-1) gene. Green transformed shoots were regenerated and rooted on medium containing phosphinothricin (PPT). Preculture and
wounding of the explants, presence of acetosyringone and PPT-based selection of transformants played significant role in enhancing
transformation frequency. Presence and expression of the bar gene in primary transformants was evidenced by PCR-Southern analysis and PPT leaf paint assay, respectively. Integration
of the Phaseolus vulgaris α-amylase inhibitor gene was confirmed by Southern blot analysis. PCR analysis revealed inheritance of both the transgenes
in most of the T1 lines. Tolerance to herbicide was evidenced from seed germination test and chlorophenol red assay in T1 plants. Transgenic plants could be recovered after 8–10 weeks of cocultivation with Agrobacterium. An overall transformation frequency of 1.51% was achieved. 相似文献