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111.
Sediments and fish bile collected from the Atlantic coastal waters of Colombia were analyzed for 16 parent polycyclic aromatic hydrocarbons (PAHs), and 23 hydroxylated PAHs (OH-PAHs), respectively. Sediments contained overall mean SigmaPAH concentrations of 2090, 234 and 170 ng/g, dry wt, for Cartagena Bay, Caimanera Marsh, and Totumo Marsh, respectively. The mean concentration of the summed OH-PAHs in fish bile was 1250, 180 and 64.1 ng/g bile wt for Cartagena Bay, Caimanera Marsh, and Totumo Marsh, respectively. The results suggest that Cartagena Bay is heavily polluted by PAHs, and that exposure to high concentrations of PAHs together with other factors could contribute to the decreased health of fish living in this ecosystem. This is one of the first studies to describe the analysis of 23 individual OH-PAHs in fish bile, using authentic standards.  相似文献   
112.
Enrichment and isolation of endosulfan degrading and detoxifying bacteria   总被引:1,自引:0,他引:1  
In the present study, degradation of endosulfan by a mixed culture isolated from a pesticide-contaminated soil was studied in batch experiments. After two weeks of incubation, the mixed culture was able to degrade 73% and 81% of alpha and beta endosulfan respectively. Endodiol was identified by GC/MS as degradation intermediate. The toxicity studies of endosulfan before and after degradation were carried out using micronucleus assay on human polymorphonuclear cells. The findings suggested that the metabolism of endosulfan isomers by the mixed culture was accompanied by significant reduction in the toxicity. Studies were also carried out to quantify the degradation potential of the individual species in the mixed bacterial culture. Two cultures identified by 16S rRNA as Stenotrophomonas maltophilia and Rhodococcus erythropolis were found to be responsible for majority of the degradation by the mixed culture. S. maltophilia showed better degradation efficiency compared to that by R. erythropolis. This is the first report of endosulfan degradation using the above-mentioned organisms.  相似文献   
113.
Adoption of soil test-based nutrient management is important for achieving sustainable development of agriculture. The present study analysed the factors influencing the adoption of soil nutrient management technology package comprising adoption of soil test and recommended fertiliser by paddy farmers in the southern Indian state of Karnataka by using field survey data. Bivariate probit model was used to estimate the sequential adoption decisions on soil test and fertiliser application technologies. The study results showed that farmers’ training on fertiliser application and education had positive and significant effect on adoption of soil nutrient technology package. The likelihood of adoption of soil test technology decreases with increase in distance measured from farm to soil test laboratory. Availability of fewer family labour increases the probability of adoption of soil nutrient management technology. These results have significant policy implications for provision of soil testing facilities nearer to villages and for conducting periodical training programmes for encouraging the farmers to adopt soil test-based nutrient management.  相似文献   
114.
The present study is aimed at evaluating the genotype frequency of detoxifying genes such as GSTM1, GSTT1 and NQO1 in Maharastrian population of central India. The study revealed about 64.6% of GSTM1-positive and 35.4% GSTM1-null population. GSTT1-positive genotype was found to be 87.5% and GSTT1-null showed 12.5%. The NQO1 genotype of Maharastrian population showed 52.3% of C/C, 42.48% C/T and 5.18% T/T. The NQO1 of this population does not deviate from the expected Hardy-Weinberg equilibrium. The genotype frequencies GSTM1 and GSTT1 of the population when compared with other ethnic groups of Asia and Caucasians show distinct nature of Maharastrian population from other Asian and Caucasian population.  相似文献   
115.
The increasing consumption and excessive extraction of conventional fuels is the matter of serious concern. Nowadays, world is looking for alternative sources of fuel which can partially replace conventional fuel dependence. The current investigation intends to provide evaluation of bio-ethanol preparation from Water Hyacinth (WH) and its influence on diesel engine performance under various operating conditions. This study explores the extraction of glucose from WH (Eichhornia crassipes) pretreated with sulfuric acid (H2SO4) for production of bio-ethanol. For the production of bio-ethanol different concentrations of H2SO4 acid hydrolysate (1%, 2%, 4%, 6%, 8%, and 10%) were prepared which was then followed by fermentation with cellulose fermenting yeasts. From results, it was observed that 4% H2SO4 acid hydrolysis produces higher concentrations of ethanol than other concentrations. Bio-ethanol extracted from WH was blended with diesel in different proportions (5%, 10%, 15%, 20%, and 25%) v/v and performance and emissions were experimentally investigated on single cylinder diesel engine under various load conditions. Experimental results show that 5 BED [5% bio-ethanol (WH + 95%diesel v/v) and 10BED (10% bio-ethanol (WH + 90%diesel v/v)] produces higher brake power, brake thermal efficiency and brake mean effective pressure with improved exhaust emission profiles than any other blend.  相似文献   
116.
Moon HB  Lee DH  Lee YS  Kannan K 《Chemosphere》2012,86(5):485-490
Very few studies have reported on the occurrence and accumulation profiles of polycyclic aromatic hydrocarbons (PAHs) and synthetic musk compounds (SMCs) in human adipose tissue. In this study, concentrations of PAHs and SMCs in adipose tissues collected from Korean women in 2007 and 2008 were determined. Total concentrations of PAHs and SMCs in adipose tissues ranged from 15 to 361 (mean: 119) ng g-1 lipid weight and from 38 to 253 (mean: 106) ng g-1 lipid weight, respectively. Concentrations of SMCs in Korean adipose tissues were lower than those reported for European countries and the United States. Naphthalene was the most predominant PAH and HHCB was the dominant SMC found in adipose tissues. The concentrations of PAHs and SMCs were not correlated with each other, suggesting that the sources of human exposure to these two classes of compounds are different. No correlation was found between donor’s age and residue levels of PAHs and SMCs. The results of this study provide baseline information on exposure of PAHs and SMCs to the general population in Korea.  相似文献   
117.
118.
Environmental Science and Pollution Research - The aim of the study was to evaluate the influence of the application of increasing proportions (0%, 10%, 25%, 50%, 75%, and 100%) of an admixture of...  相似文献   
119.
Environmental Science and Pollution Research - Phosphorus (P), an essential element for living cells, is present in different soluble and adsorbed chemical forms found in soil, sediment, and water....  相似文献   
120.

Purpose

There are many arguments on the carcinogenic potential of bitumen extract. The mechanism of bitumen-induced damage is not well understood at the molecular level. Therefore, in the present study, cell-transforming and tumor-inducing potential of bitumen extract was studied using in vitro [human osteosarcoma (HOS) cells] and in vivo [nude and severe combined immunodeficiency (SCID) mice] models.

Methods

Gas chromatography/mass spectrometry (GC/MS) analysis was carried out to find out the existence of carcinogenic compounds in the bitumen extract. Cell transformation test, anchorage independence assay, karyotyping assay, tumorigenicity assay, and 2-DE analysis were used to find out the effect of bitumen using the in vitro and in vivo models.

Results

GC/MS analysis showed the existence of carcinogenic compounds in the bitumen extract. HOS cells were treated with different concentrations (25, 50, and 100???l/ml) of bitumen extract. Compared to the parental HOS cells, bitumen transformants (HOS T1 and HOS T2) showed the characteristics of anchorage independency, chromosomal anomaly, and cellular transformation. Interestingly, bitumen transformants were not able to form tumor in nude/SCID mice. Proteomic analysis revealed the existence of 19 differentially expressed proteins involved in progression of cancer, angiogenesis, cell adhesion, etc.

Conclusions

Exposure of bitumen extract to HOS cells results in the cellular transformation similar to cancer cells and can modulate proteins involved in the progression of cancer. We state that the non-tumorogenic potential of bitumen transformant in nude/SCID mice can be attributed to the downregulation of galectin-1, chromodomain helicase DNA-binding protein 1-like gene, and membrane-associated guanylate kinase 2 protein.  相似文献   
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