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321.
Vairappan Balasubramaniyan Ruchi Shukla Gopal Murugaiyan Ramchandra Ramesh Bhonde Namasivayam Nalini 《Biochimica et Biophysica Acta (BBA)/General Subjects》2007
Obesity is a risk factor for hepatocellular carcinoma (HCC) complicated with alcoholic liver disease (ALD) and cryptogenic cirrhosis. Leptin is a 16-kDa antiobesity hormone secreted mainly by adipocytes. The role of leptin on alcohol-mediated effects in cell line is yet to be unraveled. Therefore, we investigated the effect of leptin against ethanol-elicited cytoxicity in human hepatoma cell lines (HepG2). HepG2 cells were treated with leptin (31.2 nM), ethanol (500 mM), ethanol + leptin and untreated cells served as control. 48 h after treatment, cell viability, apoptosis, TNF-α secretory response and oxidative damage were analysed. Our results suggest that leptin at a concentration of 31.2 nM prevents ethanol elicited cytotoxicity as evidenced by MTT and trypan blue dye exclusion assay. Leptin also inhibited ethanol-induced apoptosis, which was confirmed by [3H] thymidine uptake and cell cycle analysis using propidium iodide (PI) staining. Further, simultaneous leptin treatment along with ethanol showed protection against ethanol mediated cellular damage as indicated by significantly decreased levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) and significantly increased levels of reactive nitrogen species (RNS), reduced glutathione (GSH) and elevated activities of superoxide dismutase (SOD) and catalase (CAT). In addition, leptin downregulated the secretion of tumor necrosis factor-α (TNF-α) by ethanol-induced HepG2 cells. Our results demonstrate that simultaneous leptin treatment along with ethanol could be useful in preventing the damage produced by ethanol, which might be of therapeutic interest. 相似文献
322.
We examined the roots of 27 epiphytic and terrestrial species of Piperaceae collected in primary and secondary habitats in Monteverde, Costa Rica. Terrestrial roots of only two of the nine Peperomia species, two of eight Piper species, and of Pothomorphe umbellatum contained internal vesicles and/or arbuscules. We did not find internal vesicles and/or arbuscules in 3024 cm of fine roots of epiphytic Piperaceae, even though 15% of these root segments had associated external typical glomalean hyphae. Glomus and Acaulospora spores, and Gigaspora auxiliary cells occurred in both canopy and terrestrial habitats. After inoculation of a low nutrient substrate, the facultatively epiphytic Peperomia costaricensis averaged 23% mycorrhizal root length. Relatively high atmospheric inputs of dissolved inorganic nutrients that alleviate the requirement for mycorrhizae, and heterogeneity of mycorrhiza inocula in the canopy may explain the absence of mycorrhizae from epiphytic Piperaceae. We suggest that the Piperaceae comprises predominantly facultatively mycotrophic species, and that facultative mycotrophism facilitates their radiation to the canopy. 相似文献
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Nalini Yasoda Hirimuthugoda Adeniyi C. Adeola Patthamesthrige Wimal Anthony Perera Xing Chen Weligalle Wedarallage Dewar Asoka Gunawardena Humpita Gamaralalage Thilini Nisanka Gunawardana Ting‐Ting Yin Ming‐Shan Wang Gui‐Mei Li Zhao‐Li Ding Wen‐Zhi Wang Hai‐Bing Xie Min‐Sheng Peng Ya‐Ping Zhang 《Animal genetics》2017,48(5):622-623
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Singh Rajender Nalini J. Gupta Baidyanath Chakrabarty Lalji Singh Kumarasamy Thangaraj 《Steroids》2013,78(12-13):1288-1292
Inability to respond to the circulating androgens is named as androgen insensitivity syndrome (AIS). Mutations in the androgen receptor (AR) gene are the most common cause of AIS. A cause and effect relationship between some of these mutations and the AIS phenotype has been proven by in vitro studies. Several other mutations have been identified, but need to be functionally validated for pathogenicity. Screening of the AR mutations upon presumptive diagnosis of AIS is recommended. We analyzed a case of complete androgen insensitivity syndrome (CAIS) for mutations in the AR gene. Sequencing of the entire coding region revealed C > G mutation (CTT–GTT) at codon 712 (position according to the NCBI database) in exon 4 of the gene, resulting in replacement of leucine with valine in the ligand-binding domain of the AR protein. No incidence of this mutation was observed in 230 normal male individuals analyzed for comparison. In vitro androgen binding and transactivation assays using mutant clone showed approximately 71% loss of ligand binding and about 76% loss of transactivation function. We conclude that CAIS in this individual was due to L712V substitution in the androgen receptor protein. 相似文献
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We have investigated the effect of adiponectin (APN) peptide II on new vessel growth in mouse model of choroidal neovascularization (CNV) or wet type age-related macular degeneration (AMD). Mice were injected intraperitoneally with APN peptide II, control peptide, or PBS on day 1-7 or day 5-14. APN, AdipoR1, PCNA, and VEGF localization was investigated using confocal microscopy, immunohistochemistry, and RT-PCR. APN peptide II decreased the relative area of FITC-dextran perfused vessels by 4-fold, PCNA expression by 3-fold, and the number of PCNA stained HUVEC and MAVEC cells by 38 and 46%, respectively. We concluded that APN peptide II inhibits CNV size on days 7 and 14 by inhibiting the proliferation of endothelial cells in vivo and in vitro. APN peptide II may have therapeutic potential to inhibit CNV or wet AMD. 相似文献
329.
Arthropods in epiphytes: a diversity component that is not effectively sampled by canopy fogging 总被引:1,自引:0,他引:1
Stephen P. Yanoviak Nalini M. Nadkarni Jon C. Gering 《Biodiversity and Conservation》2003,12(4):731-741
Insecticide fogging is often used to document arthropod species richnessin forest canopies, but this technique may not effectively sample invertebratesthat are concealed within a variety of microhabitats. We quantified the effectsof fogging on invertebrates in canopy epiphyte mats of a Costa Rican cloudforest by extracting arthropods from 18 paired pre- and post-fogging samples.Mean abundance and morphospecies richness of living arthropods were respectivelyreduced by 33 and 30% in epiphyte material after fogging, but most organismssurvived the treatment. Relative abundances of major taxa were unaffected byfogging. Herbivores were less abundant after fogging than other trophic groups,and the median body length of non-mite arthropods present in epiphytes wassignificantly smaller after fogging. Examination of seven post-fogging samplesshowed that many arthropods killed by insecticide remained trapped within theepiphyte material. These results provide the first quantitative assessment of aspecific component of arboreal arthropod biodiversity that is missed by thefogging technique. 相似文献
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