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Blimp-1-Dependent IL-10 Production by Tr1 Cells Regulates TNF-Mediated Tissue Pathology 总被引:1,自引:0,他引:1
Marcela Montes de Oca Rajiv Kumar Fabian de Labastida Rivera Fiona H Amante Meru Sheel Rebecca J. Faleiro Patrick T. Bunn Shannon E. Best Lynette Beattie Susanna S. Ng Chelsea L. Edwards Werner Muller Erika Cretney Stephen L. Nutt Mark J. Smyth Ashraful Haque Geoffrey R. Hill Shyam Sundar Axel Kallies Christian R. Engwerda 《PLoS pathogens》2016,12(1)
Tumor necrosis factor (TNF) is critical for controlling many intracellular infections, but can also contribute to inflammation. It can promote the destruction of important cell populations and trigger dramatic tissue remodeling following establishment of chronic disease. Therefore, a better understanding of TNF regulation is needed to allow pathogen control without causing or exacerbating disease. IL-10 is an important regulatory cytokine with broad activities, including the suppression of inflammation. IL-10 is produced by different immune cells; however, its regulation and function appears to be cell-specific and context-dependent. Recently, IL-10 produced by Th1 (Tr1) cells was shown to protect host tissues from inflammation induced following infection. Here, we identify a novel pathway of TNF regulation by IL-10 from Tr1 cells during parasitic infection. We report elevated Blimp-1 mRNA levels in CD4+ T cells from visceral leishmaniasis (VL) patients, and demonstrate IL-12 was essential for Blimp-1 expression and Tr1 cell development in experimental VL. Critically, we show Blimp-1-dependent IL-10 production by Tr1 cells prevents tissue damage caused by IFNγ-dependent TNF production. Therefore, we identify Blimp-1-dependent IL-10 produced by Tr1 cells as a key regulator of TNF-mediated pathology and identify Tr1 cells as potential therapeutic tools to control inflammation. 相似文献
105.
Jiancai Wang Ronghua Xu Ruling Wang Mohammad Enamul Haque 《Bioscience, biotechnology, and biochemistry》2016,80(6):1214-1222
The conversion of acetyl-CoA to malonyl-CoA by acetyl-CoA carboxylase (ACC) is the rate-limiting step in fatty acid biosynthesis. In this study, a gene coding for ACC was isolated and characterized from an oleaginous yeast, Lipomyces starkeyi. Real-time quantitative PCR (qPCR) analysis of L. starkeyi acetyl-CoA carboxylase gene (LsACC1) showed that the expression levels were upregulated with the fast accumulation of lipids. The LsACC1 was co-overexpressed with the glycerol 3-phosphate dehydrogenase gene (GPD1), which regulates lipids biosynthesis by supplying another substrates glycerol 3-phosphate for storage lipid assembly, in the non-oleaginous yeast Saccharomyces cerevisiae. Further, the S. cerevisiae acetyl-CoA carboxylase (ScACC1) was transferred with GPD1 and its function was analyzed in comparison with LsACC1. The results showed that overexpressed LsACC1 and GPD1 resulted in a 63% increase in S. cerevisiae. This study gives new data in understanding of the molecular mechanisms underlying the regulation of fatty acids and lipid biosynthesis in yeasts. 相似文献
106.
Md. Dilshad Manzar Wassilatul Zannat Jamal Ali Moiz David Warren Spence Seithikurippu R. Pandi-Perumal Ahmed S. Bahammam 《Biological Rhythm Research》2016,47(6):851-864
The Pittsburgh Sleep Quality Index (PSQI) is a rigorously validated questionnaire with extensive use in sleep assessment. Findings from numerous factor analytic studies of the PSQI have been interpreted to support a heterogeneous factor structure model for the test. Nevertheless, the literature continues to lack a focused evaluation of whether this heterogeneous factor structure is justified. A consideration of this issue led to a conclusion that a closer analysis of the PSQI’s factor structure was merited. To address this need a comparative confirmatory factor analysis for assessing the performance of the accepted factors models of the PSQI was conducted. A sample of university students (n = 418), age = 20.92 ± 1.81 years, BMI = 23.30 ± 2.57 kg/m2 completed the multi-structured sleep survey at Jamia Millia Islamia, New Delhi, India. Seventeen putative factor structures (three 1-Factor, eight 2-Factor, and six 3-Factor) of the PSQI from the existing literature were selected for analysis. Fourteen models (82.35%) had almost similar values for model fit indices. Two models were misfits, and one model was a poor fit. The two misfit models incorporated gender and age as covariates. The third poor fit model was used to produce a unique path diagram, which made it distinct from the remaining 16 models. The overlapping values in the fit range of the model fit indices did not support the often projected heterogeneous factor structures of the PSQI for the vast majority of the models. 相似文献
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Md Ruhul Amin Nabanita Paul Nancy Md Ramiz Uddin Miah Md Giashuddin Miah Ohseok Kwon Sang Jae Suh 《Entomological Research》2019,49(5):223-228
The study was conducted with the aim of furthering our understanding of seasonality in the population dynamics and infestation rates of the fruit fly Bactrocera spp. in sweet gourd (Cucurbita moschata) during winter and summer in 2017. We also investigated the effects of using methyl eugenol traps on fly abundance and infestation. Two fruit fly species, namely, B. cucurbitae and B. dorsalis, were present in the sweet gourd field, and we observed fluctuations in their abundance. Compared to B. dorsalis, B. cucurbitae was significantly more abundant in both winter and summer. Infestation level was found to be the highest in fields lacking methyl eugenol traps in both seasons. Fruit fly larval population per infested fruit was higher in summer than in winter. Fly abundance was significantly and positively correlated with mean temperature and rainfall but significantly and negatively correlated with light intensity. Relative humidity was insignificantly but positively correlated with fly abundance. The temperature, light intensity, relative humidity, and rainfall individually explained 48.9, 24.1, 0.8, and 1.6% of variation in fruit fly abundance, respectively. The combined effect of the weather parameters on fruit fly abundance was 75.4% and was significant predictor of fruit fly abundance. 相似文献
108.
Md Saad Amir Putra Prakoso Akbar Teguh Sulong M. A. Basri Hasan Wahjuningrum Dian Agustin Syahrom Ardiyansyah 《Biomechanics and modeling in mechanobiology》2019,18(3):797-811
Biomechanics and Modeling in Mechanobiology - This study employs a computational approach to analyse the impact of morphological changes on the structural properties of biodegradable porous Mg... 相似文献
109.
Anukul Maji Maidul Beg Somnath Das Nandan Kumar Sahoo Pradeep K. Jha Md. Maidul Islam Maidul Hossain 《Luminescence》2019,34(6):563-575
This study describes the eco‐friendly, low‐cost and room‐temperature synthesis of gold nanoparticles from Musa balbisiana leaf extract, which acts as both reducing and stabilizing agent, and characterized by ultraviolet?visible (UV–vis) light spectroscopy, fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FE‐SEM), analytical transmission electron microscopy (TEM), energy‐dispersive X‐ray spectroscopy (EDAX) and dynamic light scattering (DLS) instruments. These nanoparticles showed an average diameter of 33.83 ± 3.39 nm, which was confirmed from the size distribution histogram. The bactericidal activity of these nanoparticles was confirmed using bacteria Escherichia coli and Staphylococcus aureus at 1 and 2 nM minimum inhibitory concentrations, respectively. The interaction between nanoparticles and human serum albumin (HSA) was investigated, as this plays significant roles in biological systems. The nature of interaction, binding parameters and structural variation of HSA in the presence of these nanoparticles have been evaluated using several useful spectroscopic approaches such as UV–vis, FTIR, time‐resolved and steady‐state fluorescence, and circular dichroism in addition to the measurement of zeta potential. This interaction study revealed that static quenching occurs in this process with minimal alteration in the secondary structure, but the native structure of HSA remained unaltered. The binding constant and thermodynamic parameters of this interaction process were also evaluated. 相似文献
110.
Khalek Md. Abdul Chakma Sujan Ahmed Kawsar Paul Bikash Kumar Vigneswaran Dhasarathan Zakaria Rozalina 《Plasmonics (Norwell, Mass.)》2019,14(4):861-867
Plasmonics - This article explores the effect of sensing performances with subject to change in different types of material and this study is carried out by the support of plasmon-coated photonic... 相似文献