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71.
Siddhartha Sankar Mishra Sankar Kumar Acharjee Susanta Kumar Chakraborty 《Environmental Biology of Fishes》2009,84(4):395-407
Twenty-five species of fishes belonging to 18 genera, 7 families under the order siluriformes have been recorded from different
freshwater and brackish water wetlands of South West Bengal, India. Fishery potential of 17 commercially important siluroid
fishes were noted especially from market surveys as well as from information collected from local fishermen communities. Following
the IUCN guidelines, and also through Participatory Rural Appraisal (P.R.A.) methods, an attempt has been made to assess the
conservation status of such fishes, many of which are thought to be threatened. Trend analysis, Fish Magnitude Value and Rank
based Quotient revealed the threatened status of 17 siluroid fishes. 相似文献
72.
Brijmohan Singh Bhau Kalyani Medhi Ambrish P. Das Siddhartha P. Saikia Kartik Neog S. N. Choudhury 《Biochemical genetics》2009,47(7-8):486-497
The utility of RAPD markers in assessing genetic diversity and phenetic relationships in Persea bombycina, a major tree species for golden silk (muga) production, was investigated using 48 genotypes from northeast India. Thirteen RAPD primer combinations generated 93 bands. On average, seven RAPD fragments were amplified per reaction. In a UPGMA phenetic dendrogram based on Jaccard’s coefficient, the P. bombycina accessions showed a high level of genetic variation, as indicated by genetic similarity. The grouping in the phenogram was highly consistent, as indicated by high values of cophenetic correlation and high bootstrap values at the key nodes. The accessions were scattered on a plot derived from principal correspondence analysis. The study concluded that the high level of genetic diversity in the P. bombycina accessions may be attributed to the species’ outcrossing nature. This study may be useful in identifying diverse genetic stocks of P. bombycina, which may then be conserved on a priority basis. 相似文献
73.
Discrimination of tRNAGln is an integral function of several bacterial glutamyl-tRNA synthetases (GluRS). The origin of the discrimination is thought to arise from unfavorable interactions between tRNAGln and the anticodon-binding domain of GluRS. From experiments on an anticodon-binding domain truncated Escherichia coli (E. coli) GluRS (catalytic domain) and a chimeric protein, constructed from the catalytic domain of E. coli GluRS and the anticodon-binding domain of E. coli glutaminyl-tRNA synthetase (GlnRS), we show that both proteins discriminate against E. coli tRNAGln. Our results demonstrate that in addition to the anticodon-binding domain, tRNAGln discriminatory elements may be present in the catalytic domain in E. coli GluRS as well. 相似文献
74.
Impacts of Community-based Conservation on Local Communities in the Annapurna Conservation Area, Nepal 总被引:1,自引:0,他引:1
Siddhartha B. Bajracharya Peter A. Furley Adrian C. Newton 《Biodiversity and Conservation》2006,15(8):2765-2786
Approaches to the management of protected areas that involve the participation of local communities are now being widely promoted.
However, the impacts of such community-based conservation initiatives on local communities remain poorly defined. This research
examines the socio-economic impacts of community-based conservation within the Annapurna Conservation Area (ACA), Nepal, through
semi-structured interviews and a questionnaire survey with local residents, situated both within and outside the protected
area. Results indicate that local communities have received a number of benefits from conservation, including improvements
in access to forest resources, improved basic infrastructure such as drinking water, trails and bridges, and improvements
in health, sanitation and social services. However, relatively few people (14.9%) within ACA receive direct financial income
from tourism. Local communities also experience a number of costs of being involved in conservation, the most significant
of which is increased crop damage by wildlife. Eighty-four percent of respondents within ACA have experienced problems of
crop damage, accounting for 6% (rice) to 23% (maize) of total production. Depredation of livestock by wildlife is also experienced;
mean losses per household being the equivalent of £3.9 (Rs. 479.70) each year. However, 66% of respondents within ACA reported
that they had never experienced this problem. These results indicate that the socio-economic benefits of community-based approaches
to conservation can outweigh the costs, even though the latter are significant. However, a participatory approach to management
of problematic animal species will need to be developed within ACA, if conflicts between local communities and protected area
management are to be avoided in future. 相似文献
75.
Satyendra Chandra Tripathi Ajay Matta Jatinder Kaur Jorg Grigull Shyam Singh Chauhan Alok Thakar Nootan Kumar Shukla Ritu Duggal Siddhartha DattaGupta Ranju Ralhan K. W. Michael Siu 《PloS one》2010,5(8)
Background
Tissue proteomic analysis of head and neck squamous cell carcinoma (HNSCC) and normal oral mucosa using iTRAQ (isobaric tag for relative and absolute quantitation) labeling and liquid chromatography-mass spectrometry, led to the identification of a panel of biomarkers including S100A7. In the multi-step process of head and neck tumorigenesis, the presence of dysplastic areas in the epithelium is proposed to be associated with a likely progression to cancer; however there are no established biomarkers to predict their potential of malignant transformation. This study aimed to determine the clinical significance of S100A7 overexpression in HNSCC.Methodology
Immunohistochemical analysis of S100A7 expression in HNSCC (100 cases), oral lesions (166 cases) and 100 histologically normal tissues was carried out and correlated with clinicopathological parameters and disease prognosis over 7 years for HNSCC patients. Overexpression of S100A7 protein was significant in oral lesions (squamous cell hyperplasia/dysplasia) and sustained in HNSCC in comparison with oral normal mucosa (ptrend<0.001). Significant increase in nuclear S100A7 was observed in HNSCC as compared to dysplastic lesions (p = 0.005) and associated with well differentiated squamous cell carcinoma (p = 0.031). Notably, nuclear accumulation of S100A7 also emerged as an independent predictor of reduced disease free survival (p = 0.006, Hazard ratio (HR = 7.6), 95% CI = 1.3−5.1) in multivariate analysis underscoring its relevance as a poor prognosticator of HNSCC patients.Conclusions
Our study demonstrated nuclear accumulation of S100A7 may serve as predictor of poor prognosis in HNSCC patients. Further, increased nuclear accumulation of S100A7 in HNSCC as compared to dysplastic lesions warrants a large-scale longitudinal study of patients with dysplasia to evaluate its potential as a determinant of increased risk of transformation of oral premalignant lesions. 相似文献76.
Acetohydroxyacid synthase (AHAS) is an enzyme involved in the biosynthesis of the branched chain amino acids viz, valine, leucine and isoleucine. The activity of this enzyme is regulated through feedback inhibition by the end products of the pathway. Here we report the backbone and side-chain assignments of ilvN, the 22 kDa dimeric regulatory subunit of E. coli AHAS isoenzyme I, in the valine bound form. Detailed analysis of the structure of ilvN and its interactions with the catalytic subunit of E. coli AHAS I will help in understanding the mechanism of activation and regulation of the branched chain amino acid biosynthesis. 相似文献
77.
The purpose of the present study was to examine the antioxidant activity of two typical oils obtained from two vegetables, bitter gourd seed and snake gourd seed, containing two different isomers of conjugated linolenic acid (CLnA) against oxidative stress induced by sodium arsenite in relation to tissue lipid peroxidation and inflammation. Male albino rats were taken as subject and divided into six groups: Group 1 was control and Group 2 was treated with sodium arsenite (Sa; 10mg/Kg BW); Groups 3-6 were orally treated with different doses of seed oils maintaining definite concentration of CLnA isomers (0.5% and 1.0% of total lipid for each CLnA isomer) along with sodium arsenite. There was significant increase in lipid peroxidation, pro-oxidant enzyme activity and decrease in antioxidant enzyme activity in brain due to Sa administration. Decrease in total protein content was also observed in plasma, liver and brain of Sa treated group. Significant decrease in phospholipid content and increase in total lipid content and cholesterol content were observed in arsenite treated group. There was significant increase in relative organ weight of liver due to Sa administration. Fatty acid profile of liver and brain lipid shows significant (P<0.05) reduction in most of the polyunsaturated fatty acids and increase in arachidonic acid (20:4n-6) (75.23%) due to inflammation after arsenite treatment. Administration of experimental oils made almost complete restoration of those altered parameters. Overall, these two oils were effective in protecting tissue lipid profiles which were altered due to oxidative stress. 相似文献
78.
Cytosine deaminase is a non-mammalian enzyme of widespread interest for prodrug enzyme therapy due to its ability to convert
prodrug 5-fluorocytosine into anticancer drug 5-fluorouracil. Cytosine deaminase enzyme has been purified to homogeneity from
E. coli K-12 MTCC 1302 strain. Km values for cytosine and 5-fluorocytosine were found to be 0.26 mM and 1.82 mM, respectively. We developed a chitosan-entrapped
cytosine deaminase nanocomposite. Atomic force microscopy and transmission electron microscopy images showed an elongated
sphere shape nanocomposite with an average size of 80 nm diameter. Fourier transform infrared spectroscopy and X-ray diffraction
results confirmed gel formation and entrapment of cytosine deaminase within the nanocomposite. Sustained release of cytosine
deaminase from the nanocomposite up to one week depicted its potential implication in prodrug inducted enzyme therapy. 相似文献
79.
We sampled 161 feral pigs in eastern North Carolina, USA, to determine the prevalence and antimicrobial resistance profile of Clostridium difficile and Salmonella. Seven (4.4%) and eight (5.0%) pigs tested positive for C. difficile and Salmonella, respectively, highlighting the importance of determining the epidemiology of these pathogens in feral pigs. 相似文献
80.
Fibromyalgia syndrome (FMS) is a complex chronic condition causing widespread pain and variety of other symptoms. It produces pain in the soft tissues located around joints throughout the body. FMS has unknown etiology and its pathophysiology is not fully understood. However, abnormality in circadian rhythm of hormonal profiles and cytokines has been observed in this disorder. Moreover, there are reports of deficiency of serotonin, melatonin, cortisol and cytokines in FMS patients, which are fully regulated by circadian rhythm. Melatonin, the primary hormone of the pineal gland regulates the body's circadian rhythm and normally its levels begin to rise in the mid-to-late evening, remain high for most of the night, and then decrease in the early morning. FMS patients have lower melatonin secretion during the hours of darkness than the healthy subjects. This may contribute to impaired sleep at night, fatigue during the day and changed pain perception. Studies have shown blunting of normal diurnal cortisol rhythm, with elevated evening serum cortisol level in patients with FMS. Thus, due to perturbed level of cortisol secretion several symptoms of FMS may occur. Moreover, disturbed cytokine levels have also been reported in FMS patients. Therefore, circadian rhythm can be an important factor in the pathophysiology, diagnosis and treatment of FMS. This article explores the circadian pattern of abnormalities in FMS patients, as this may help in better understanding the role of variation in symptoms of FMS and its possible relationship with circadian variations of melatonin, cortisol, cytokines and serotonin levels. 相似文献