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141.
Venkateswarlu Popuri Jing Huang Mahesh Ramamoorthy Takashi Tadokoro Deborah L. Croteau Vilhelm A. Bohr 《Nucleic acids research》2013,41(2):881-899
Humans have five RecQ helicases, whereas simpler organisms have only one. Little is known about whether and how these RecQ helicases co-operate and/or complement each other in response to cellular stress. Here we show that RECQL5 associates longer at laser-induced DNA double-strand breaks in the absence of Werner syndrome (WRN) protein, and that it interacts physically and functionally with WRN both in vivo and in vitro. RECQL5 co-operates with WRN on synthetic stalled replication fork-like structures and stimulates its helicase activity on DNA fork duplexes. Both RECQL5 and WRN re-localize from the nucleolus into the nucleus after replicative stress and significantly associate with each other during S-phase. Further, we show that RECQL5 is essential for cell survival in the absence of WRN. Loss of both RECQL5 and WRN severely compromises DNA replication, accumulates genomic instability and ultimately leads to cell death. Collectively, our results indicate that RECQL5 plays both co-operative and complementary roles with WRN. This is an early demonstration of a significant functional interplay and a novel synthetic lethal interaction among the human RecQ helicases. 相似文献
142.
Background
Food insecurity is associated with poor nutritional and clinical outcomes among people living with HIV/AIDS. Few studies investigate the link between food insecurity, dietary diversity and health-related quality of life among people living with HIV/AIDS.Objective
We investigated whether household food access and individual dietary diversity are associated with health-related quality of life among people living with HIV/AIDS in Uganda.Methods
We surveyed 902 people living with HIV/AIDS and their households from two clinics in Northern Uganda. Health-related quality of life outcomes were assessed using the Medical Outcomes Study (MOS)-HIV Survey. We performed multivariate regressions to investigate the relationship between health-related quality of life, household food insecurity and individual dietary diversity.Results
People living with HIV/AIDS from severe food insecurity households have mean mental health status scores that are 1.7 points lower (p<.001) and physical health status scores that are 1.5 points lower (p<.01). Individuals with high dietary diversity have mean mental health status scores that were 3.6 points higher (p<.001) and physical health status scores that were 2.8 points higher (p<.05).Conclusions
Food access and diet quality are associated with health-related quality of life and may be considered as part of comprehensive interventions designed to mitigate psychosocial consequences of HIV. 相似文献143.
Subhadra Nandakumar Sunil Kannanganat Karen M. Dobos Megan Lucas John S. Spencer Sunan Fang Melissa A. McDonald Jan Pohl Kristin Birkness Venkateswarlu Chamcha Melissa V. Ramirez Bonnie B. Plikaytis James E. Posey Rama Rao Amara Suraj B. Sable 《PLoS pathogens》2013,9(10)
Glycosylation is the most abundant post-translational polypeptide chain modification in nature. Although carbohydrate modification of protein antigens from many microbial pathogens constitutes important components of B cell epitopes, the role in T cell immunity is not completely understood. Here, using ELISPOT and polychromatic flow cytometry, we show that O-mannosylation of the adhesin, Apa, of Mycobacterium tuberculosis (Mtb) is crucial for its T cell antigenicity in humans and mice after infection. However, subunit vaccination with both mannosylated and non-mannosylated Apa induced a comparable magnitude and quality of T cell response and imparted similar levels of protection against Mtb challenge in mice. Both forms equally improved waning BCG vaccine-induced protection in elderly mice after subunit boosting. Thus, O-mannosylation of Apa is required for antigenicity but appears to be dispensable for its immunogenicity and protective efficacy in mice. These results have implications for the development of subunit vaccines using post-translationally modified proteins such as glycoproteins against infectious diseases like tuberculosis. 相似文献
144.
Joao A.Paulo Vivek Kadiyala Peter A.Banks Darwin L.Conwell Hanno Steen 《基因组蛋白质组与生物信息学报(英文版)》2013,11(2):105-113
The functions of the liver and the pancreas differ; however, chronic inflammation in both organs is associated with fibrosis. Evidence suggests that fibrosis in both organs is partially regulated by organ-specific stellate cells. We explore the proteome of human hepatic stellate cells (hHSC) and human pancreatic stellate cells (hPaSC) using mass spectrometry (MS)-based quantitative proteomics to investigate pathophysiologic mechanisms. Proteins were isolated from whole cell lysates of immortalized hHSC and hPaSC. These proteins were tryptically digested, labeled with tandem mass tags (TMT), fractionated by OFFGEL, and subjected to MS. Proteins significantly different in abundance (P < 0.05) were classified via gene ontology (GO) analysis. We identified 1223 proteins and among them, 1222 proteins were quantifiable. Statistical analysis determined that 177 proteins were of higher abundance in hHSC, while 157 were of higher abundance in hPaSC. GO classification revealed that proteins of relatively higher abundance in hHSC were associated with protein production, while those of relatively higher abundance in hPaSC were involved in cell structure. Future studies using the methodologies established herein, but with further upstream fractionation and/or use of enhanced MS instrumentation will allow greater proteome coverage, achieving a comprehensive proteomic analysis of hHSC and hPaSC. 相似文献
145.
Reddy DK Shekhar V Prabhakar P Babu DC Ramesh D Siddhardha B Murthy US Venkateswarlu Y 《Bioorganic & medicinal chemistry letters》2011,21(3):997-1000
A simple, first stereoselective total synthesis of botryolide-E has been described. The synthesis started from propylene oxide employing Jacobsen’s hydrolytic kinetic resolution (HKR), selective epoxide opening, sharpless asymmetric dihydroxylation, one pot acetonide deprotection and lactonization as key steps. Further, the synthesis confirms the absolute configuration of the natural product botryolide-E and we evaluated the biological behavior of natural product botryolide-E against a panel of bacteria and fungi. Botryolide-E exhibits significant potent activity against Staphylococcus aureus (MTCC 96) (6.25 μg/ml), good against Escherichia coli (MTCC 443) (12.5 μg/ml), Bacillus subtilis (MTCC 441) (25 μg/ml) and compound 1 exhibited good to moderate antifungal activity. 相似文献
146.
Yihui Tu Huaming Xue Wendy Francis Andrew P. Davies Ian Pallister Venkateswarlu Kanamarlapudi Zhidao Xia 《Biochemical and biophysical research communications》2013
Dexamethasone (Dex) is commonly used for osteoarthritis (OA) with excellent anti-inflammatory and analgesic effect. However, Dex also has many side effects following repeated use over prolonged periods mainly through increasing apoptosis and inhibiting proliferation. Lactoferrin (LF) exerts significantly anabolic effect on many cells and little is known about its effect on OA chondrocytes. Therefore, the aim of this study is to investigate whether LF can inhibit Dex-induced OA chondrocytes apoptosis and explore its possible molecular mechanism involved in. MTT assay was used to determine the optimal concentration of Dex and recombinant human LF (rhLF) on chondrocytes at different time and dose points. Chondrocytes were then stimulated with Dex in the absence or presence of optimal concentration of rhLF. Cell proliferation and viability were evaluated using MTT and LIVE/DEAD assay, respectively. Cell apoptosis was evaluated by multi-parameter apoptosis assay kit using both confocal microscopy and flow cytometry, respectively. The expression of extracellular signal-regulated kinase (ERK), FAS, FASL, and Caspase-3 (CASP3) at the mRNA and protein levels were examined by real-time polymerase chain reaction (PCR) and immunocytochemistry, respectively. The optimal concentration of Dex (25 μg/ml) and rhLF (200 μg/ml) were chosen for the following experiments. rhLF significantly reversed the detrimental effect of Dex on chondrocytes proliferation, viability, and apoptosis. In addition, rhLF significantly prevented Dex-induced down-regulation of ERK and up-regulation of FAS, FASL, and CASP3. These findings demonstrated that rhLF acts as an anabolic effect on chondrocytes through significantly reversing Dex-induced chondrocytes apoptosis. This study may contribute to further investigating the clinical application of LF on OA. 相似文献
147.
148.
Biological activity of phenylpropionic acid isolated from a terrestrial Streptomycetes. 总被引:1,自引:0,他引:1
Kolla J P Narayana Peddikotla Prabhakar Muvva Vijayalakshmi Yenamandra Venkateswarlu Palakodety S J Krishna 《Polish journal of microbiology》2007,56(3):191-197
The strain ANU 6277 was isolated from laterite soil and identified as Streptomyces sp. closely related to Streptomyces albidoflavus cluster by 16S rRNA analysis. The cultural, morphological and physiological characters of the strain were recorded. The strain exhibited resistance to chloramphenicol, penicillin and streptomycin. It had the ability to produce enzymes such as amylase and chitinase. A bioactive compound was isolated from the strain at stationary phase of culture and identified as 3-phenylpropionic acid (3-PPA) by FT-IR, EI-MS, 1H NMR and 13C NMR spectral studies. It exhibited antimicrobial activity against different bacteria like Bacillus cereus, B. subtilis, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, P. flourescens, Staphylococcus aureus and some fungi including Aspergillus flavus, A. niger, Candida albicans, Fusarium oxysporum, F. udum and Penicillium citrinum. The antifungal activity of 3-PPA of the strain was evaluated in in vivo and in vitro conditions against Fusarium udum causing wilt disease in pigeon pea. The compound 3-PPA is an effective antifungal agent when compared to tricyclozole (fungicide) to control wilt caused by F. udum, but it exhibited less antifungal activity than carbendazim. 相似文献
149.
Saiko P Graser G Madlener S Schwarz S Krupitza G Jaeger W Somepalli V Golakoti T Fritzer-Szekeres M Szekeres T 《Nucleosides, nucleotides & nucleic acids》2011,30(12):1190-1196
Digalloylresveratrol (DIG) is a newly synthesized agent aimed to combine the biological effects of the natural compounds, gallic acid and resveratrol, which both are free radical scavengers exhibiting anticancer activity. In this study, we investigated the effects of DIG on the growth of human HL-60 leukemia cells and on the colony formation of human BxPC-3 and PANC-1 pancreatic cancer cells. DIG was applied alone and in combination with arabinofuranosylcytosine (Ara-C) or difluorodeoxycytidine (dFdC), depending on the cell line employed. All IC(50) values observed were in the low micromolar range rendering DIG a promising antitumor compound in vitro. Considering the combination experiments, DIG yielded additive effects with Ara-C in HL-60 cells and-to a lesser extent-with dFdC in BxPC-3 and PANC-1 cells. Owing to our results, DIG may be further investigated in vitro and in animals. 相似文献
150.