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961.
Ghangal Rajesh Rajkumar Mohan Singh Garg Rohini Jain Mukesh 《Molecular biology reports》2020,47(4):2749-2761
Molecular Biology Reports - Glutathione S-transferases (GSTs) are multifunctional proteins that help in oxidative stress metabolism and detoxification of xenobiotic compounds. Studies pertaining to... 相似文献
962.
Kristiansen SB Henning O Kharbanda RK Nielsen-Kudsk JE Schmidt MR Redington AN Nielsen TT Bøtker HE 《American journal of physiology. Heart and circulatory physiology》2005,288(3):H1252-H1256
Local and remote ischemic preconditioning (IPC) reduce ischemia-reperfusion (I/R) injury and preserve cardiac function. In this study, we tested the hypothesis that remote preconditioning is memorized by the explanted heart and yields protection from subsequent I/R injury and that the underlying mechanism involves sarcolemmal and mitochondrial ATP-sensitive K(+) (K(ATP)) channels. Male Wistar rats (300-350 g) were randomized to a control (n = 10), a remote IPC (n = 10), and a local IPC group (n = 10). Remote IPC was induced by four cycles of 5 min of limb ischemia, followed by 5 min of reperfusion. Local IPC was induced by four cycles of 2 min of regional myocardial ischemia, followed by 3 min of reperfusion. The heart was excised within 5 min after the final cycle of preconditioning, mounted in a perfused Langendorff preparation for 40 min of stabilization, and subjected to 45 min of sustained ischemia by occluding the left coronary artery and 120 min of reperfusion. I/R injury was assessed as infarct size by triphenyltetrazolium staining. The influence of sarcolemmal and mitochondrial K(ATP) channels on remote preconditioning was assessed by the addition of glibenclamide (10 microM, a nonselective K(ATP) blocker), 5-hydroxydecanoic acid (5-HD; 100 microM, a mitochondrial K(ATP) blocker), and HMR-1098 (30 microM, a sarcolemmal K(ATP) blocker) to the Langendorff preparation before I/R. The role of mitochondrial K(ATP) channels as an effector mechanism for memorizing remote preconditioning was further studied by the effect of the specific mitochondrial K(ATP) activator diaxozide (10 mg/kg) on myocardial infarct size. Remote preconditioning reduced I/R injury in the explanted heart (0.17 +/- 0.03 vs. 0.39 +/- 0.05, P < 0.05) and improved left ventricular function during reperfusion compared with control (P < 0.05). Similar effects were obtained with diazoxide. Remote preconditioning was abolished by the addition of 5-HD and glibenclamide but not by HMR-1098. In conclusion, the protective effect of remote preconditioning is memorized in the explanted heart by a mechanism that involves mitochondrial K(ATP) channels. 相似文献
963.
964.
965.
Effect of growth retardants (paclobutrazol or ancymidol) was studied in Lilium plantlets growing in liquid culture. A significant increase in leaf chlorophyll, epicuticular wax, plant dry weight and bulb
starch contents were found in plantlets treated with growth retardants. A similar increase in the number of leaves, roots
and bulbs was also noted. However, total leaf area and the fresh weight increased only marginally. These features resulted
in robust plantlets that showed significantly improved ex vitro survival. Based on these features, a comprehensive index (CI)
was calculated as a measure of quality of the plantlets, and it correlated well with their ex vitro survival. Treatment of
plantlets with 3.4 μM paclobutrazol was found to be the best and its carry over effects were also minimal. 相似文献
966.
Bahekar RH Jain MR Jadav PA Prajapati VM Patel DN Gupta AA Sharma A Tom R Bandyopadhya D Modi H Patel PR 《Bioorganic & medicinal chemistry》2007,15(21):6782-6795
In the present investigation, two series of 2,5-disubstituted-3-imidazol-2-yl-pyrrolo[2,3-b]pyridines (2a-l) and thieno[2,3-b]pyridines (3a-l) were designed as analogs of BL 11282 (1). The in vitro glucose dependent insulinotropic activity of all the test compounds was evaluated using RIN5F cell based assay and all the test compounds showed glucose and concentration dependent insulin secretion. The in vivo antidiabetic activities of most potent compounds from each series (2c and 3c) were assessed in C57BL/6J mice. Compounds 2c and 3c showed dose dependent insulin secretion and significant glucose reduction in vivo. In general, compounds 2c and 3c were found to be equipotent at all the three different doses selected and with respect to BL 11282, both the test compounds were found to be more potent, at all the time points. 相似文献
967.
Isolation and characterization of cellulose-degrading bacteria from the deep subsurface of the Homestake gold mine,Lead, South Dakota,USA 总被引:3,自引:0,他引:3
Gurdeep Rastogi Geetha L. Muppidi Raghu N. Gurram Akash Adhikari Kenneth M. Bischoff Stephen R. Hughes William A. Apel Sookie S. Bang David J. Dixon Rajesh K. Sani 《Journal of industrial microbiology & biotechnology》2009,36(4):585-598
The present study investigated the cultivable mesophilic (37°C) and thermophilic (60°C) cellulose-degrading bacterial diversity
in a weathered soil-like sample collected from the deep subsurface (1.5 km depth) of the Homestake gold mine in Lead, South
Dakota, USA. Chemical characterization of the sample by X-ray fluorescence spectroscopy revealed a high amount of toxic heavy
metals such as Cu, Cr, Pb, Ni, and Zn. Molecular community structures were determined by phylogenetic analysis of 16S rRNA
gene sequences retrieved from enrichment cultures growing in presence of microcrystalline cellulose as the sole source of
carbon. All phylotypes retrieved from enrichment cultures were affiliated to Firmicutes. Cellulose-degrading mesophilic and thermophilic pure cultures belonging to the genera Brevibacillus, Paenibacillus, Bacillus, and Geobacillus were isolated from enrichment cultures, and selected cultures were studied for enzyme activities. For a mesophilic isolate
(DUSELG12), the optimum pH and temperature for carboxymethyl cellulase (CMCase) were 5.5 and 55°C, while for a thermophilic
isolate (DUSELR7) they were 5.0 and 75°C, respectively. Furthermore, DUSELG12 retained about 40% CMCase activity after incubation
at 60°C for 8 h. Most remarkably, thermophilic isolate, DUSELR7 retained 26% CMCase activity at 60°C up to a period of 300 h.
Overall, the present work revealed the presence of different cellulose-degrading bacterial lineages in the unique deep subsurface
environment of the mine. The results also have strong implications for biological conversion of cellulosic agricultural and
forestry wastes to commodity chemicals including sugars. 相似文献
968.
The aim of this study was to explore the relationship of intracellular glutathione with various oxidative stress markers and the stress protectant marker trehalose. In the first group of yeast cells, diethyl maleate was used for depletion of glutathione. A second group of yeast cells were incubated with amino acids constituting glutathione (GIu, Cys, Gly) to increase glutathione level. Increased level of oxidative stress marker like ROS, protein carbonyl formation and lipid peroxidation and decreased viability in glutathione-depleted cells were observed in the present study. The increased activity of antioxidant enzymes SOD and CAT in the glutathione depleted group suggests the interaction of different antioxidant defence system in Pachysolen tannophilus. Furthermore, the increased levels of trehalose in glutathione-depleted group shows that trehalose acts as a stress reducer in glutathione depleted Pachysolen tannophilus. 相似文献
969.
Background
Coupled with the largest number of maternal deaths, adolescent pregnancy in India has received paramount importance due to early age at marriage and low contraceptive use. The factors associated with the utilization of maternal healthcare services among married adolescents in rural India are poorly discussed.Methodology/Principal Findings
Using the data from third wave of National Family Health Survey (2005–06), available in public domain for the use by researchers, this paper examines the factors associated with the utilization of maternal healthcare services among married adolescent women (aged 15–19 years) in rural India. Three components of maternal healthcare service utilization were measured: full antenatal care, safe delivery, and postnatal care within 42 days of delivery for the women who gave births in the last five years preceding the survey. Considering the framework on causes of maternal mortality proposed by Thaddeus and Maine (1994), selected socioeconomic, demographic, and cultural factors influencing outcome events were included as the predictor variables. Bi-variate analyses including chi-square test to determine the difference in proportion, and logistic regression to understand the net effect of predictor variables on selected outcomes were applied. Findings indicate the significant differences in the use of selected maternal healthcare utilization by educational attainment, economic status and region of residence. Muslim women, and women belonged to Scheduled Castes, Scheduled Tribes, and Other Backward Classes are less likely to avail safe delivery services. Additionally, adolescent women from the southern region utilizing the highest maternal healthcare services than the other regions.Conclusions
The present study documents several socioeconomic and cultural factors affecting the utilization of maternal healthcare services among rural adolescent women in India. The ongoing healthcare programs should start targeting household with married adolescent women belonging to poor and specific sub-groups of the population in rural areas to address the unmet need for maternal healthcare service utilization. 相似文献970.
The NEF gene is conserved among members of human and simian immunodeficiency viruses and may play an important role in viral pathogenesis. To determine the evolutionary dynamics and conservation of functionality of the human immunodeficiency virus type 1 (HIV-1) NEF gene during maternal-fetal transmission, we analyzed NEF sequences from seven mother-infant pairs following perinatal transmission, including a mother with infected twin infants. The NEF open reading frame was maintained in mother-infant isolates with a frequency of 86.2% following vertical transmission. While there was a low degree of viral heterogeneity and estimates of genetic diversity and high population growth rates of NEF sequences from mother-infant isolates, the infants' NEF sequences were slightly higher with respect to these parameters compared with the mothers' sequences. Both the mothers' and infants' NEF sequences were under positive selection pressure, as determined by a new method of Nielsen and Yang [Genetics 148:929-936;1998]. Based on genetic distance and phylogenetic parameters, the epidemiologically linked NEF sequences from mother-infant pairs were closer to each other compared with epidemiologically unlinked sequences from individuals. The functional domains essential for Nef activity, including membrane binding, CD4 and MHC-I downmodulation, T cell activation and interaction with factors of the cellular protein trafficking machinery, were conserved in most of the sequences from mother-infant pairs. The maintenance of intact NEF open reading frames with conserved functional domains and a low degree of genetic variability following vertical transmission supports the notion that NEF plays an important role in HIV-1 infection and replication in mothers and their perinatally infected infants. 相似文献