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1.
Oropharyngeal cancer is a significant public health issue in the world. The incidence of oropharyngeal cancer has been increased among people who have habit of chewing smokeless tobacco (SLT) in Pakistan. The aim of present study was to evaluate the concentration of nickel (Ni) in biological samples (whole blood, serum) of oral (n?=?95) and pharyngeal (n?=?84) male cancer patients. For comparison purposes, the biological samples of healthy age-matched referents (n?=?150), who consumed and did not consumed SLT products, were also analyzed for Ni levels. As the Ni level is very low in biological samples, a preconcentration procedure has been developed, prior to analysis of analyte by flame atomic absorption spectrometry (FAAS). The Ni in acid-digested biological samples was complexed with ammonium pyrrolidinedithio carbamate (APDC), and a resulted complex was extracted in a surfactant Triton X-114. Acidic ethanol was added to the surfactant-rich phase prior to its analysis by FAAS. The chemical variables, such as pH, amounts of reagents (APDC, Triton X-114), temperature, incubation time, and sample volume were optimized. The resulted data indicated that concentration of Ni was higher in blood and serum samples of cancer patients as compared to that of referents who have or have not consumed different SLT products (p?=?0.012–0.001). It was also observed that healthy referents who consumed SLT products have two to threefold higher levels of Ni in both biological samples as compared to those who were not chewing SLT products (p? Figure
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2.
Brassinosteroids (BRs) are involved in the amelioration of various biotic and abiotic stresses. With an aim to explore the role of BRs under heavy metal stress, plants of Brassica juncea L. were grown in pots. The plants were subjected to various concentrations of Nickel metal (0.0, 0.2, 0.4 and 0.6 mM) and harvested on 60th day in order to observe the expression of these hormones. The isolated BRs from the leaves of Brassica plants characterized by GC-MS include 24-Epibrassinolide (24-EBL), Castasterone, Dolicholide and Typhasterole. The effect of isolated 24-EBL was studied on Ni metal uptake and antioxidative defense system in 60 d old plants of Brassica. It was observed that 24-EBL significantly increased the activities of stress ameliorating enzymes and lowered the metal uptake in plants. This is the first report in B. juncea L. plants showing the expression of BRs under metal treatments and effect of the isolated 24-EBL on metal uptake and in oxidative stress management.  相似文献   
3.
Arora, Kapil, Steven K. Mickelson, Matthew J. Helmers, and James L. Baker, 2010. Review of Pesticide Retention Processes Occurring in Buffer Strips Receiving Agricultural Runoff. Journal of the American Water Resources Association (JAWRA) 46(3):618-647. DOI: 10.1111/j.1752-1688.2010.00438.x Abstract: Review of the published results shows that the retention of the two pesticide carrier phases (runoff volume and sediment mass) influences pesticide mass transport through buffer strips. Data averaged across different studies showed that the buffer strips retained 45% of runoff volume (ranging between 0 and 100%) and 76% of sediment mass (ranging between 2 and 100%). Sorption (soil sorption coefficient, Koc) is one key pesticide property affecting its transport with the two carrier phases through buffer strips. Data from different studies for pesticide mass retention for weakly (Koc < 100), moderately (100 < Koc < 1,000), and strongly sorbed pesticides (Koc > 1,000) averaged (with ranges) 61 (0-100), 63 (0-100), and 76 (53-100) %, respectively. Because there are more data for runoff volume and sediment mass retention, the average retentions of both carrier phases were used to calculate that the buffer strips would retain 45% of weakly to moderately sorbed and 70% of strongly sorbed pesticides on an average basis. As pesticide mass retention presented is only an average across several studies with different experimental setups, the application of these results to actual field conditions should be carefully examined.  相似文献   
4.
The extent to which smokeless tobacco endangers human health is an ongoing subject of debate. In this study, concentrations of toxic metals, cadmium (Cd), lead (Pb), and nickel (Ni), were measured in different snuff products (dry brown and black and moist green and brown), available and consumed in Pakistan. Concentrations of Cd, Pb, and Ni were determined in 23 samples of various brands of snuff by electrothermal atomic absorption spectrometry, after microwave-assisted acid digestion. The reliability of methodology was assured by analyzing certified reference material. The resulted data of toxic metals in different snuff products are comparable to the existing information with limited exceptions. It was estimated that 10 g intake of different types of snuff could contribute 14–68, 17–47, and 20–73 % of the provisional maximum tolerable daily intake for Cd, Ni, and Pb, respectively.  相似文献   
5.
Environment Systems and Decisions - For mission critical (MC) applications such as bushfire emergency management systems (EMS), understanding the current situation as a disaster unfolds is critical...  相似文献   
6.
Environmental Science and Pollution Research - Type 2 diabetes (T2D) is one of the most widely spread metabolic disorder also called as “life style” disease. Due to the alarming number...  相似文献   
7.
Environmental Science and Pollution Research - The mitochondria, apart from being known as the cell’s “powerhouse,” are crucial in the viability of nerve cells. Any damage to...  相似文献   
8.
Effectof exopolysaccharides (EPS) produced by a consortium of cyanobacteria on germination of three crops wheat, maize and rice was studied at different salt concentrations. Production of EPS was found to be stimulated by salts, which in turn had a significant Na+ removal capability from aqueous solution. Seed germination, vigor index and mobilization efficiency in all the three crops remarkably improved when cyanobacterial EPS was applied. While germination improved significantly by 13 to 30%, mobilization efficiency increased marginally by 1.03 to 1.1 times and vigor index increased by 1.15 to 2.4 times in these crops in response to EPS under non-saline conditions. Salinity had an inhibitory effect on seed germination of all the species showing 18 to 54% reduction. However, in the presence of EPS, the salt induced inhibition diminished to 13 to 18%. Inhibitory effect of salt on chlorophyll concentration, vigor index and mobilization efficiency of the seedlings was much less in these crops in the presence of EPS, indicating the latter's role in salt stress alleviation.  相似文献   
9.
Commiphora mukul commonly known as Guggul is one of the oldest and commonly consumed herb for promoting heart and vascular health. Present study was undertaken to evaluate cardioprotective potential of Commiphora mukul against isoprenaline-induced myocardial necrosis in rats. Wistar albino rats were divided into three main groups: sham (saline only), isoprenaline control (saline and isoprenaline) and Commiphora mukul treated (Commiphora mukul and isoprenaline) groups. Commiphora mukul was administered in three doses 100, 200 and 400 mg kg(-1) p.o. for 30 days. On 29th and 30th day, the animals of isoprenaline control and Commiphora mukulpretreatment groups were administered isoprenaline (85 mg kg(-1); s.c.), consecutively at an interval of 24 hr. Isoprenaline administration produced a significant (p < 0.05) decrease in myocardial antioxidants; superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx), reduced glutathione (GSH), and myocyte injury marker enzymes creatine-phosphokinase-MB (CK-MB) and lactate dehydrogenase (LDH) along with enhanced lipid peroxidation; malondialdehyde (MDA) in heart. Commiphora mukul pretreatment reversed the isoprenaline-induced oxidative changes in rat myocardium by significant (p < 0.05) increase in SOD, CAT, GSHPx, GSH and reduction of MDA. In addition to improving myocardial antioxidant status, Commiphora mukul also prevented the leakage of LDH and CK-MB from heart. Further, histopathological examination showed the reduction of necrosis, edema and inflammation following Commiphora mukul pretreatment. Based on present findings, it is concluded that Commiphora mukul may be a potential preventive and therapeutic agent against the oxidative stress associated ischemic heart disease owing to antioxidant and antiperoxidative activity.  相似文献   
10.
In the present study, we have investigated the influence of polymorphism of GSTM1 and GSTT1 genes and confounding factors such as age, sex, exposure duration and consumption habits on cytogenetic biomarkers. Frequency of sister chromatid exchanges (SCEs), high frequency cell (HFC) and cytokinesis blocked micronuclei (CBMN) were evaluated in peripheral blood lymphocytes of 115 occupationally exposed road construction workers and 105 unexposed individuals. The distribution of null and positive genotypes of glutathione-S transferase gene was evaluated by multiplex PCR among control and exposed subjects. An increased frequency of CBMN (7.03 ± 2.08); SCE (6.95 ± 1.76) and HFC (6.28 ± 1.69) were found in exposed subjects when compared to referent (CBMN - 3.35 ± 1.10; SCE - 4.13 ± 1.30 and HFC - 3.98 ± 1.56). These results were found statistically significant at p < 0.05. When the effect of confounding factors on the frequency of studied biomarkers was evaluated, a strong positive interaction was found. The individuals having GSTM1 and GSTT1 null genotypes had higher frequency of CBMN, SCE and HFC. The association between GSTM1 and GSTT1 genotypes and studied biomarkers was found statistically significant at p < 0.05. Our findings suggest that individuals having null type of GST are more susceptible to cytogenetic damage by occupational exposure regardless of confounding factors. There is a significant effect of polymorphism of these genes on cytogenetic biomarkers which are considered as early effects of genotoxic carcinogens.  相似文献   
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