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71.
Protective effect of coenzyme Q10 in simvastatin and gemfibrozil induced rhabdomyolysis in rats 总被引:1,自引:0,他引:1
Farswan M Rathod SP Upaganlawar AB Semwal A 《Indian journal of experimental biology》2005,43(10):845-848
Administration of simvastatin (80 mg/kg, po. evening dose) and gemfibrozil (600 mg/kg, po twice) for 30 days produced significant decrease in the level of reduced glutathione, superoxide dismutase, catalase and increase in the level of lipid peroxidation and various serum parameters (creatine phosphokinase, lactate dehydrogenase, serum glutamate oxaloacetate transaminase, creatinine, urea and blood urea nitrogen). This suggested involvement of oxidative stress in rhabdomyolysis. Increase in the level of reduced glutathione, superoxide dismutase, catalase and decrease in the level of lipid peroxidation and serum parameters after administration of antioxidant CoQ10 (10 mg/kg.ip) proved the protective effect of CoQ10 in rhabdomyolysis. 相似文献
72.
Pillai AD Rani S Rathod PD Xavier FP Vasu KK Padh H Sudarsanam V 《Bioorganic & medicinal chemistry》2005,13(4):1275-1283
73.
Eastman RT White J Hucke O Bauer K Yokoyama K Nallan L Chakrabarti D Verlinde CL Gelb MH Rathod PK Van Voorhis WC 《The Journal of biological chemistry》2005,280(14):13554-13559
The post-translational farnesylation of proteins serves to anchor a subset of intracellular proteins to membranes in eukaryotic organisms and also promotes protein-protein interactions. Inhibition of protein farnesyltransferase (PFT) is lethal to the pathogenic protozoa Plasmodium falciparum. Parasites were isolated that were resistant to BMS-388891, a tetrahydroquinoline (THQ) PFT inhibitor. Resistance was associated with a 12-fold decrease in drug susceptibility. Genotypic analysis revealed a single point mutation in the beta subunit in resistant parasites. The resultant tyrosine 837 to cysteine alteration in the beta subunit corresponded to the binding site for the THQ and peptide substrate. Biochemical analysis of Y837C-PFT demonstrated a 13-fold increase in BMS-388891 concentration necessary for inhibiting 50% of the enzyme activity. These data are consistent with PFT as the target of BMS-388891 in P. falciparum and suggest that PFT inhibitors should be combined with other antimalarial agents for effective therapy. 相似文献
74.
Shrikant I. Bangdiwala 《Biometrical journal. Biometrische Zeitschrift》1989,31(2):203-211
In survivorship modelling using the proportional hazards model of Cox (1972, Journal of the Royal Statistical Society, Series B, 34, 187–220), it is often desired to test a subset of the vector of unknown regression parameters β in the expression for the hazard rate at time t. The likelihood ratio test statistic is well behaved in most situations but may be expensive to calculate. The Wald (1943, Transactions of the American Mathematical Society 54, 426–482) test statistic is easier to calculate, but has some drawbacks. In testing a single parameter in a binomial logit model, Hauck and Donner (1977, Journal of the American Statistical Association 72, 851–853) show that the Wald statistic decreases to zero the further the parameter estimate is from the null and that the asymptotic power of the test decreases to the significance level. The Wald statistic is extensively used in statistical software packages for survivorship modelling and it is therefore important to understand its behavior. The present work examines empirically the behavior of the Wald statistic under various departures from the null hypothesis and under the presence of Type I censoring and covariates in the model. It is shown via examples that the Wald statistic's behavior is not as aberrant as found for the logistic model. For the single parameter case, the asymptotic non-null distribution of the Wald statistic is examined. 相似文献
75.
Ritesh K. Baboota Siddhartha M. Sarma Ravneet K. Boparai Kanthi Kiran Kondepudi Shrikant Mantri Mahendra Bishnoi 《PloS one》2015,10(5)
BackgroundTwo types of adipose tissues, white (WAT) and brown (BAT) are found in mammals. Increasingly novel strategies are being proposed for the treatment of obesity and its associated complications by altering amount and/or activity of BAT using mouse models.ConclusionOur study provides evidence for inter species (mouse vs human) differences in differential gene expression between sWAT and BAT. Critical understanding of this data may help in development of novel ways to engineer one form of adipose tissue to another using murine model with focus on human. 相似文献
76.
Ultrasound‐assisted three‐phase partitioning of polyphenol oxidase from potato peel (Solanum tuberosum)
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Conventional three phase partitioning (TPP) and ultrasound assisted three phase partitioning (UATPP) were optimized for achieving the maximum extraction and purification of polyphenol oxidase ( PPO) from waste potato peels. Different process parameters such as ammonium sulfate (NH4)2SO4 concentration, crude extract to t‐butanol ratio, time, temperature and pH were studied for conventional TPP. Except agitation speed, the similar parameters were also optimized for UATPP. Further additional parameters were also studied for UATPP viz. irradiation time at different frequencies, duty cycle and, rated power in order to obtain the maximum purification factor and recovery of PPO. The optimized conditions for conventional TPP were (NH4)2SO4 0‐40% (w/v), extract to t‐butanol ratio 1:1 (v/v), time 40 min and pH 7 at 30°C. These conditions provided 6.3 purification factor and 70% recovery of PPO from bottom phase. On the other hand, UATPP gives maximum purification fold of 19.7 with 98.3% recovery under optimized parameters which includes (NH4)2SO4 0‐40% (w/v), crude extract to t‐butanol ratio 1: 1 (v/v) pH 7, irradiation time 5 min with 25 kHz, duty cycle 40% and rated power 150W at 30°C. UATPP delivers higher purification factor and % recovery of PPO along with reduced operation time from 40 min to 5 min when compared with TPP. SDS PAGE showed partial purification of PPO enzyme with UATPP with molecular weight in the range of 26‐36 kDa. Results reveal that UATPP would be an attractive option for the isolation and purification of PPO without need of multiple steps. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1340–1347, 2015 相似文献
77.
One decade after the sequencing of the Plasmodium falciparum genome, 95% of malaria proteins in the genome cannot be expressed in traditional cell-based expression systems, and the targets of the best new leads for antimalarial drug discovery are either not known or not available in functional form. For a disease that kills up to 1 million people per year, routine expression of recombinant malaria proteins in functional form is needed both for the discovery of new therapeutics and for identification of targets of new drugs. We tested the general utility of cell-free systems for expressing malaria enzymes. Thirteen test enzyme sequences were reverse amplified from total RNA, cloned into a plant-like expression vector, and subjected to cell-free expression in a wheat germ system. Protein electrophoresis and autoradiography confirmed the synthesis of products of expected molecular masses. In rare problematic cases, truncated products were avoided by using synthetic genes carrying wheat codons. Scaled-up production generated 39 to 354 μg of soluble protein per 10 mg of translation lysate. Compared to rare proteins where cell-based systems do produce functional proteins, the cell-free yields are comparable or better. All 13 test products were enzymatically active, without failure. This general path to produce functional malaria proteins should now allow the community to access new tools, such as biologically active protein arrays, and lead to the discovery of new chemical functions, structures, and inhibitors of previously inaccessible malaria gene products. 相似文献
78.
P. Fine Paresh H. Rathod A. Beriozkin U. Mingelgrin 《International journal of phytoremediation》2013,15(6):585-601
The potential suitability of Eucalyptus camaldulensis for Cd phytoextraction was tested in a hydroponic study. Saplings were exposed to 4.5 and 89 μM Cd for one month, with and without EDTA and s,s-EDDS at 0.1, 1, and 5 mM. The saplings’ growth was not affected at the 4.5 μM Cd concentration, yet it decreased 3-fold at 89 μM, and almost all the Cd taken up was immobilized in the roots, reaching 360 and 5300 mg Cd kg?1, respectively (approximately 75% of which was non-washable in acid). The respective Cd root-to-shoot translocation factors were 0.14 and ≈5*10?4. At 0.1 mM concentration, EDTA and EDDS had no effect or even a positive effect on the saplings growth. This was reversed at 1 mM, and the chelants became lethal at the 5 mM concentration. At 89 μM Cd in the growth medium, 0.1 mM EDTA increased Cd translocation into the shoots by almost 10-fold, however it strongly reduced Cd content inside the roots. This hydroponic study indicates the feasibility of E. camaldulensis use for cleanup Cd-contaminated soils at environmental concentrations, both for site stabilization (phytostabilization) and gradual remediation (phytoextraction). EDTA was shown to be much more efficient in enhancing Cd translocation than s,s-EDDS. 相似文献
79.
Lichtnekert J Kulkarni OP Mulay SR Rupanagudi KV Ryu M Allam R Vielhauer V Muruve D Lindenmeyer MT Cohen CD Anders HJ 《PloS one》2011,6(10):e26778
IL-1β and IL-18 are proinflammatory cytokines that contribute to renal immune complex disease, but whether IL-1β and IL-18 are mediators of intrinsic glomerular inflammation is unknown. In contrast to other cytokines the secretion of IL-1β and IL-18 requires a second stimulus that activates the inflammasome-ASC-caspase-1 pathway to cleave pro-IL-1β and -IL-18 into their mature and secretable forms. As the NLRP3 inflammasome and caspase-1 were shown to contribute to postischemic and postobstructive tubulointerstitial inflammation, we hypothesized a similar role for NLRP3, ASC, and caspase-1 in glomerular immunopathology. This concept was supported by the finding that lack of IL-1R1 reduced antiserum-induced focal segmental necrosis, crescent formation, and tubular atrophy when compared to wildtype mice. Lack of IL-18 reduced tubular atrophy only. However, NLRP3-, ASC- or caspase-1-deficiency had no significant effect on renal histopathology or proteinuria of serum nephritis. In vitro studies with mouse glomeruli or mesangial cells, glomerular endothelial cells, and podocytes did not reveal any pro-IL-1β induction upon LPS stimulation and no caspase-1 activation after an additional exposure to the NLRP3 agonist ATP. Only renal dendritic cells, which reside mainly in the tubulointerstitium, expressed pro-IL-1β and were able to activate the NLRP3-caspase-1 axis and secrete mature IL-1β. Together, the NLRP3-ASC-caspase-1 axis does not contribute to intrinsic glomerular inflammation via glomerular parenchymal cells as these cannot produce IL-1β during sterile inflammation. 相似文献
80.