RESUMO
Toxic metal contamination in soils due industrialization is nowadays a concern to the scientists worldwide. The current study deals with the evaluation of response and tolerance by isolated metallophilic bacteria in different lead concentrations (100 ppm to 1000 ppm). By taking optical densities of the isolates, the minimum inhibitory concentration (MIC) of Pb2+ were determined.16S rRNA and MALDI-TOF MS were used for the identification of the bacteria. Total of 37 isolates were observed, among them 04 (Staphylococcus equorum, Staphylococcus warneri, Bacillus safensis and Bacillus thuringiensis), isolated were detected having efficacy of Pb2+tolerance and sequestration at varying MIC. Furthermore, B. thuringiensis was observed to have highest (900 ppm) tolerance for lead and lowest (500 ppm) for Staphylococcus warneri. Moreover, the highest (65.3%) sequestration potential has been observed for B. thuringiensis and least (52.8%) for S. warneri. The tolerance and sequestration potential properties of these isolated species can be utilised to exterminate heavy metals and reduce their toxicity from the contaminated environment.
RESUMO
Studies on associations of various polymorphisms in xenobiotic metabolizing genes with different cancers including acute lymphoblastic leukaemia (ALL) are mixed and inconclusive. The current study analyzed the relationship between polymorphisms of phase I xenobiotic metabolizing enzymes, cytochromes P450 1A1 (CYP1A1) and CYP2D6 and childhood ALL in Kashmir, India. We recruited 200 confirmed ALL cases, and an equal number of controls, matched for sex, age and district of residence to the respective case. Information was obtained on various lifestyle and environmental factors in face to face interviews with the parents/attendants of each subject. Genotypes of CYP1A1 and CYP2D6 were analyzed by polymerase chain reaction and restriction fragment length polymorphism method. Logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). Compared to the GG genotype, we found a higher ALL risk in subjects who harbored variant (AA) genotype (OR=20.9; 95% CI: 6.01-73.1, P<0.0001) and AG genotype (OR=42.6; 95% CI: 8.3-217.5, P<0.0001) of CYP2D6*4 polymorphism. Although, we found a significant association of CYP1A1*2A polymorphism with ALL risk, but the risk did not persist in the adjusted model (OR=6.76; 95% CI: 0.63-71.8, P=0.100). The study indicates that unlike CYP1A1*2A, CYP2D6*4 polymorphism is associated with ALL risk. However, more replicative studies with larger sample size are needed to substantiate our findings.