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61.
Choi K Roh SG Hong YH Shrestha YB Hishikawa D Chen C Kojima M Kangawa K Sasaki S 《Endocrinology》2003,144(3):754-759
Recent research progress indicates a close link between ghrelin, a natural ligand of GH secretagogues receptor (GHS-R), and both the metabolic balance and body composition. To clarify the involvement of ghrelin and GHS-R in the process of adipogenesis, we measured the expression of GHS-R and peroxisome proliferator-activated receptor gamma 2 (PPAR-gamma 2) mRNA in rat adipocytes using semiquantitative RT-PCR methods. The levels of GHS-R mRNA increased by up to 4-fold in adipose tissue from epididymal and parametrial regions as the rat aged from 4-20 wk and were significantly elevated during the differentiation of preadipocytes in vitro. Ghrelin (10(-8) M for 10 d) stimulated the activity of glycerol-3-phosphate dehydrogenase and the differentiation of rat preadipocytes in vitro. Ghrelin treatment also significantly increased the levels of PPAR-gamma 2 mRNA in primary cultured rat differentiated adipocytes. In addition, isoproterenol (10(-8) M, 40 min)-stimulated lipolysis was significantly reduced by simultaneous ghrelin treatment in a dose-dependent manner in vitro. In conclusion, the expression of GHS-R in rat adipocytes increases with the age and during adipogenesis. Ghrelin in vitro stimulates the differentiation of preadipocytes and antagonizes lipolysis. Ghrelin may therefore play an important role in the process of adipogenesis in rats. 相似文献
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Clinical and Epidemiological Relevance of Quantitating Hepatitis E Virus-Specific Immunoglobulin M 下载免费PDF全文
Jitvimol Seriwatana Mrigendra P. Shrestha Robert M. Scott Sergei A. Tsarev David W. Vaughn Khin Saw Aye Myint Bruce L. Innis 《Clinical and Vaccine Immunology : CVI》2002,9(5):1072-1078
Diagnosis of acute hepatitis E by detection of hepatitis E virus (HEV)-specific immunoglobulin M (IgM) is an established procedure. We investigated whether quantitation of HEV IgM and its ratio to HEV total Ig furnished more information than conventional IgM tests that are interpreted as positive or negative. A previously described indirect immunoassay for total Ig against a baculovirus-expressed HEV capsid protein was modified to quantitate HEV-specific IgM in Walter Reed (WR) antibody units by using a reference antiserum and the four-parameter logistic model. A receiver-operating characteristics curve derived from 197 true-positive specimens and 449 true-negative specimens identified 30 WR units/ml as an optimum cut point. The median HEV IgM level in 36 patients with acute hepatitis E fell from 3,000 to 100 WR units/ml over 6 months, suggesting that 100 WR units/ml would be a more appropriate cut point for distinguishing recent from remote IgM responses. Among three hepatitis E case series, determination of the HEV IgM-to-total-Ig ratio in acute-phase serum revealed that most patients had high ratios consistent with primary infections whereas a few had low ratios, suggesting that they had sustained reinfections that elicited anamnestic antibody responses. The diagnostic utility of the new IgM test was similar to that of a commercially available test that uses different HEV antigens. In conclusion, we found that HEV IgM can be detected specifically in >95% of acute hepatitis E cases defined by detection of the virus genome in serum and that quantitation of HEV IgM and its ratio to total Ig provides insight into infection timing and prior immunity. 相似文献
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Martagon-Villamil J Shrestha N Sholtis M Isada CM Hall GS Bryne T Lodge BA Reller LB Procop GW 《Journal of clinical microbiology》2003,41(3):1295-1298
We designed and tested a real-time LightCycler PCR assay for Histoplasma capsulatum that correctly identified the 34 H. capsulatum isolates in a battery of 107 fungal isolates tested and also detected H. capsulatum in clinical specimens from three patients that were culture positive for this organism. 相似文献
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Maria Mathisen Tor A Strand Biswa N Sharma Ram K Chandyo Palle Valentiner-Branth Sudha Basnet Ramesh K Adhikari Dag Hvidsten Prakash S Shrestha Halvor Sommerfelt 《BMC medicine》2009,7(1):35
Background
Pneumonia is among the main causes of illness and death in children <5 years of age. There is a need to better describe the epidemiology of viral community-acquired pneumonia (CAP) in developing countries. 相似文献67.
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Nashi Widodo Kamaljit Kaur Bhupal G Shrestha Yasuomi Takagi Tetsuro Ishii Renu Wadhwa Sunil C Kaul 《Clinical cancer research》2007,13(7):2298-2306
PURPOSE: Ashwagandha is regarded as a wonder shrub of India and is commonly used in Ayurvedic medicine and health tonics that claim its variety of health-promoting effects. Surprisingly, these claims are not well supported by adequate studies, and the molecular mechanisms of its action remain largely unexplored to date. We undertook a study to identify and characterize the antitumor activity of the leaf extract of ashwagandha. EXPERIMENTAL DESIGN: Selective tumor-inhibitory activity of the leaf extract (i-Extract) was identified by in vivo tumor formation assays in nude mice and by in vitro growth assays of normal and human transformed cells. To investigate the cellular targets of i-Extract, we adopted a gene silencing approach using a selected small hairpin RNA library and found that p53 is required for the killing activity of i-Extract. RESULTS: By molecular analysis of p53 function in normal and a variety of tumor cells, we found that it is selectively activated in tumor cells, causing either their growth arrest or apoptosis. By fractionation, purification, and structural analysis of the i-Extract constituents, we have identified its p53-activating tumor-inhibiting factor as with a none. CONCLUSION: We provide the first molecular evidence that the leaf extract of ashwagandha selectively kills tumor cells and, thus, is a natural source for safe anticancer medicine. 相似文献
70.
Manandhar K Shrestha B 《Journal of epidemiology / Japan Epidemiological Association》2000,10(6):410-413
Sera from 478 healthy Nepalese male population, inhabiting various districts of five development regions of Nepal were collected from October 1996 to March 1997 and examined for the presence of HBsAg by third generation ELISA and Latex agglutination test in the laboratory of Central Department of Microbiology, Tribhuvan University, Kirtipur. The surface antigen was detected by ELISA in 4.0% (19/478) of subjects studied. However, different results were obtained in Latex agglutination test. The correlation between the results obtained from these two different tests is statistically significant (chi2=85.11, P<0.05). The results obtained from ELISA showed the probability of Nepal to fall in WHO category of intermediate endemicity zone for hepatitis B infection. The percent positivity of HBsAg was found to increase steadily from Eastern (2%) to Far Western (6.2%) development regions. Among the districts studied, Kailali district gave characteristically high prevalence followed by Rukum and Kaski. Other, districts representing for the prevalence are Sankhuwasabha, Jhapa, Ramechhap, Sarlahi, Dhanusa, Baglung, Gulmi, Palpa and Dang. None of the samples represented from Kathmandu valley were positive for HBsAg. The age groups of 16-20 years and 36-40 years were found to be associated with the hepatitis B infection. Furthermore, various percent prevalence of the infection were encountered from 16 to 40 years subjects and a single case was also observed from 63 years old man. All the samples recorded positive for HBsAg from ELISA were assayed for the amount of ALT as a liver function test. Where, 15.8% (3/19) of the infected subjects had impaired liver function, hence it showed that, the subjects with high ALT to be the possible carrier of the HBV. Conversely, the remaining 84.2% (16/19) of the total HBsAg positive subjects were concluded to have the infection either at incubation or at prodrome period. 相似文献