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921.
Ihsan R Devi TR Yadav DS Mishra AK Sharma J Zomawia E Verma Y Phukan R Mahanta J Kataki AC Kapur S Saxena S 《DNA and cell biology》2011,30(3):163-171
The association of TP53 codon 72 polymorphism with cancer susceptibility remains uncertain and varies with ethnicity. Northeast India represents a geographically, culturally, and ethnically isolated population. The area reports high rate of tobacco usage in a variety of ways of consumption, compared with the rest of Indian population. A total of 411 cancer patients (161 lung, 134 gastric, and 116 oral) and 282 normal controls from the ethnic population were analyzed for p53 codon 72 polymorphism by polymerase chain reaction-restriction fragment length polymorphism. No significant difference in genotypic distribution of p53 between cases and controls was observed. Results suggested betel quid chewing as a major risk factor for all the three cancers (odds ratio [OR]=3.54, confidence interval [CI]=2.01-6.25, p<0.001; OR=1.74, CI=1.04-2.92, p=0.03; and OR=1.85, CI=1.02-3.33, p=0.04 for lung, gastric, and oral cancers, respectively). Tobacco smoking was associated with risk of lung and oral cancers (OR=1.88, CI=1.11-3.19, p=0.01 and OR=1.68, CI=1.00-2.81, p=0.04). Interactions between p53 genotypes and risk factors were analyzed to look for gene-environment interactions. Interaction of smoking and p53 genotype was significant only for oral cancer. Interactions of betel quid with p53 genotypes in lung cancer showed significant increase for all the three genotypes, indicating a major role of betel quid (OR=5.90, CI=1.67-20.81, p=0.006; OR=5.44, CI=1.67-17.75, p=0.005; and OR=5.84, CI=1.70-19.97, p=0.005 for Arg/Arg, Arg/Pro, and Pro/Pro, respectively). In conclusion, high incidence of these cancers in northeast India might be an outcome of risk habits; further, tissue- and carcinogen-specific risk modification by p53 gene is probable. 相似文献
922.
923.
Rhus verniciflua Stokes (RVS), traditionally used as a food supplement and in traditional herbal medicine for centuries in Korea, is known
to possess various pharmacological properties. Environmental neurotoxins such as rotenone, a specific inhibitor of complex
I provide models of Parkinson’s disease (PD) both in vivo and in vitro. In this study, we investigated the neuroprotective
effect of RVS against rotenone-induced toxicity in human dopaminergic cells, SH-SY5Y. Cells exposed to rotenone for 24 h-induced
cellular injury and apoptotic cell death. Pretreatment of cells with RVS provided significant protection to SH-SY5Y cells.
Further, RVS offered remarkable protection against rotenone-induced oxidative stress and markedly inhibited mitochondrial
membrane potential (MMP) disruption. RVS also attenuated the up-regulation of Bax, Caspase-9 and Caspase-3 and down-regulation
of Bcl-2. Moreover, pretreatment with RVS prevented the decrease in tyrosine hydroxylase (TH) levels in SH-SY5Y cells. Interestingly,
RVS conferred profound protection to human dopaminergic cells by preventing the downregulation of brain-derived neurotrophic
factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF). These results suggest that RVS may protect dopaminergic
neurons against rotenone-induced apoptosis by multiple functions and contribute to neuroprotection in neurodegenerative diseases,
such as PD. 相似文献
924.
The beneficial effect of seed priming in improving critical growth stages like seed germination and early growth phases has been accepted by Plant Physiologists for many important field crops. In the present investigation, studies were made to see the effect of heavy metal stress imposed during germination using solution of HgCl2 in four different concentrations (0.0, 0.50, 0.75 and 1.00 mM) in Petri dishes on primed and non-primed seeds of wheat. Priming has been done with distilled water (hydro), Mg(NO3)2 and Ca(NO3)2 (halo) salts. Different germination parameters, such as germination percentage, radicle and plumule lengths, seedling emergence, soluble and insoluble sugar contents and activity of α-amylase in endosperm were studied at different study periods. Primed seeds increased all the germination parameters except insoluble sugar content in respect to non-primed control in the absence of HgCl2. However, the use of primed seeds has shown to overcome the inhibitory effects of heavy metal stress imposed in the form of HgCl2 solution during the period of germination. Hence, the work concludes the mitigating effects of priming under heavy metal stress. 相似文献
925.
926.
927.
Ankit Kumar Yadav Suman Manna K. Pandiyan Arjun Singh Murugan Kumar Hillol Chakdar Prem Lal Kashyap Alok Kumar Srivastava 《Microbiology》2016,85(1):56-62
Among hydrocarbon pollutants, diesel oil is a complex mixture of alkanes and aromatic compounds which are often encountered as soil contaminants leaking from storage tanks and pipelines or as result of accidental spillage. One of the best ecofriendly approaches is to restore contaminated soil by using microorganisms able to degrade those toxic compounds in a bioremediation process. In the present study, nineteen bacteria were isolated by enrichment culture technique from diesel spilled soil collected from electric generator shed of NBAIM, Mau. All the isolates were subjected to screening for lipase production and twelve isolates were found to be positive for lipase. When the isolates were screened for biosurfactant production using CTAB-methylene blue agar plates, only one isolate viz. 2NBDSH3 was found positive which was found to be phylogenetically closely related with Bacillus flexus. Despite having low emulsification index, the bacterium could degrade 88.6% of diesel oil in soil. Biosurfactant from the isolate was extracted and characterized through infra-red spectroscopy which indicated its possible lipopeptide nature which was further supported by strong absorption in UV range in the UV-Vis spectrum. The results of the present study indicated that the isolate either does not produce any bioemulsifier or produces very low amount of emulsifier rather it produces a lipopeptide biosurfactant which helps in degradation of diesel oil by lowering the surface tension. The bacterium thus isolated and characterized can serve as a promising solution for ecofriendly remediation of bacterium diesel contaminated soils. 相似文献
928.
Sunil Kumar Narwal Nitin Kumar Saun Priyanka Dogra Reena Gupta 《Russian Journal of Bioorganic Chemistry》2016,42(1):69-73
Isoamyl acetate, a pear or banana flavor, is widely used in food, beverage, cosmetic, and pharmaceutical industries. In the present work, lipase from Bacillus aerius was immobilized on silica gel matrix in the presence of a cross-linking agent, glutaraldehyde, and its efficiency in synthesizing isoamyl acetate using esterification reaction was studied. The esterification of acetic acid and isoamyl alcohol by silica-bound lipase was studied as a function of time and temperatures. The incubation time of 10 h, temperature of 55°C, substrate molar ratio 1: 1, and the amount of lipase as 1% were found to be optimal for the esterification reaction. The bound lipase catalyzed the esterification of acetic acid by isoamyl alcohol with the yield of about 68% under the optimized reaction conditions. The product was identified as isoamyl acetate using gas-liquid chromatography, nuclear magnetic resonance, and Fourier transform IR spectroscopy analysis by the presence of an ester group at the wavenumber of 1720.5 cm–1. 相似文献
929.
Raghavendra Mishra 《Ocean Development & International Law》2016,47(1):29-39
The judgments in maritime delimitation cases involving Bangladesh and Myanmar (2012) and between Bangladesh and India (2014) have resulted in a “Grey Area” in the northern Bay of Bengal involving intersecting and overlapping rights and responsibilities in terms of the exclusive economic zone (EEZ) and continental shelf regimes. This article seeks to identify a functional solution for this Grey Area. 相似文献
930.
Sunil Kumar 《Archives Of Phytopathology And Plant Protection》2016,49(1-4):59-63
Pepper seed samples were tested for the infection of tobacco mosaic virus (TMV) and tomato mosaic virus (ToMV) by enzyme linked immunosorbent assay (ELISA). Out of 26 pepper seed samples tested, 17 were infected with TMV and ToMV in ELISA. About 34.7% of pepper seed samples were found to be healthy. Infections of TMV or ToMV were recorded to be 61.53% and 11.5%, respectively of the total tested seed samples. 相似文献