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991.
992.
993.
Sonemany Salinthone Vijayshree Yadav Robynn V. Schillace Dennis N. Bourdette Daniel W. Carr 《PloS one》2010,5(9)
Background
Abnormal regulation of the inflammatory response is an important component of diseases such as diabetes, Alzheimer''s disease and multiple sclerosis (MS). Lipoic acid (LA) has been shown to have antioxidant and anti-inflammatory properties and is being pursued as a therapy for these diseases. We first reported that LA stimulates cAMP production via activation of G-protein coupled receptors and adenylyl cyclases. LA also suppressed NK cell activation and cytotoxicity. In this study we present evidence supporting the hypothesis that the anti-inflammatory properties of LA are mediated by the cAMP/PKA signaling cascade. Additionally, we show that LA oral administration elevates cAMP levels in MS subjects.Methodology/Principal Findings
We determined the effects of LA on IL-6, IL-17 and IL-10 secretion using ELISAs. Treatment with 50 µg/ml and 100 µg/ml LA significantly reduced IL-6 levels by 19 and 34%, respectively, in T cell enriched PBMCs. IL-17 levels were also reduced by 35 and 50%, respectively. Though not significant, LA appeared to have a biphasic effect on IL-10 production. Thymidine incorporation studies showed LA inhibited T cell proliferation by 90%. T-cell activation was reduced by 50% as measured by IL-2 secretion. Western blot analysis showed that LA treatment increased phosphorylation of Lck, a downstream effector of protein kinase A. Pretreatment with a peptide inhibitor of PKA, PKI, blocked LA inhibition of IL-2 and IFN gamma production, indicating that PKA mediates these responses. Oral administration of 1200 mg LA to MS subjects resulted in increased cAMP levels in PBMCs four hours after ingestion. Average cAMP levels in 20 subjects were 43% higher than baseline.Conclusions/Significance
Oral administration of LA in vivo resulted in significant increases in cAMP concentration. The anti-inflammatory effects of LA are mediated in part by the cAMP/PKA signaling cascade. These novel findings enhance our understanding of the mechanisms of action of LA. 相似文献994.
Dinesh DS Das ML Picado A Roy L Rijal S Singh SP Das P Boelaert M Coosemans M 《PLoS neglected tropical diseases》2010,4(10):e859
Objectives
To investigate the DDT and deltamethrin susceptibility of Phlebotomus argentipes, the vector of Leishmania donovani, responsible for visceral leishmaniasis (VL), in two countries (India and Nepal) with different histories of insecticide exposure.Methods
Standard WHO testing procedures were applied using 4% DDT and 0.05% deltamethrin impregnated papers. The effect of the physiological status (fed and unfed) of females on the outcome of the bioassays was assessed and the optimal time of exposure for deltamethrin was evaluated on a colony population. Field populations from both countries were tested.Results
Fed and unfed females responded in a similar way. For exposure time on field samples 60 min was adopted for both DDT and deltamethrin. In Bihar, knockdown and mortality with DDT was respectively 20 and 43%. In Nepal almost all sand flies were killed, except at the border with Bihar (mortality 62%). With 0.05% deltamethrin, between 96 and 100% of the sand flies were killed in both regions.Conclusions
Based on literature and present data 4% DDT and 0.05% deltamethrin seem to be acceptable discriminating concentrations to separate resistant from susceptible populations. Resistance to DDT was confirmed in Bihar and in a border village of Nepal, but the sand flies were still susceptible in villages more inside Nepal where only synthetic pyrethroids are used for indoor spraying. The low effectiveness of indoor spraying with DDT in Bihar to control VL can be partially explained by this resistance hence other classes of insecticides should be tested. In both countries P. argentipes sand flies were susceptible to deltamethrin. 相似文献995.
Arundhati Nanda Sangram Keshori Mohanty Rudraksh Sovan Panda Lambodar Behera Anand Prakash Sarat Chandra Sahu 《Tropical plant biology》2010,3(4):219-226
The Asian rice gall midge, Orseolia oryzae Wood-Mason (Cecidomyiidae: Diptera) is a serious pest of wet season rice in South and Southeast Asia. Due to internal feeding habit and presence of biotypes of the pest, the most feasible way to control is breeding varieties resistant against multiple biotypes through marker-assisted breeding (MAB). But very few versatile co-dominant markers linked to the gall midge resistance genes are available. We used a set of F9 recombinant inbred lines (RILs) of the cross TN1/PTB10 and identified microsatellite markers for the gall midge resistance gene in cv. PTB10 on short arm of rice chromosome 8. Markers RM22550 and RM547 flank the gene at a distance of 0.9 and 1.9 cM, respectively. Amplification of the markers in gall midge resistant and susceptible cultivars showed that these markers can be successfully used in MAB for development of gall midge resistant varieties. 相似文献
996.
T. Vijaya Lakshmi Y. Varalaxmi S. K. Yadav M. Maheswari 《Russian Journal of Plant Physiology》2017,64(6):889-898
Antioxidative enzyme activities and their isozyme patterns under water-deficit, salinity, high and low temperature stresses were studied in the seedlings of Pennisetum glaucum (L.) R.Br. It was observed that under water-deficit stress glutathione reductase (GR) was the key enzyme while in case of high temperature stress, GR along with catalase played a major role. Superoxide dismutase was found to be the main enzyme under low temperature stress. Co-ordinated higher expression of all the antioxidative enzymes was observed under salt stress. This study revealed the operation of different enzymatic antioxidative mechanisms under various abiotic stresses that will aid in understanding the metabolic basis of stress tolerance in pearl millet. 相似文献
997.
Nagarani Thotakura Mukesh Dadarwal Pramod Kumar Gajanand Sharma Santosh Kumar Guru Shashi Bhushan Kaisar Raza Om Prakash Katare 《AAPS PharmSciTech》2017,18(3):759-768
Chitosan is a widely employed polysaccharide with positive zeta-potential and better tissue/cell adhesion. Its hydrophilicity, high viscosity, and insolubility at physiological pH are major hurdles in proper utilization of this macromolecule. Therefore, it was conjugated with biocompatible stearic acid and the conjugate was employed to develop polymeric micelles for delivery of tamoxifen to breast cancer cells. The conjugate was characterized by FT-IR and NMR, and the nanocarrier was characterized for micromeritics, surface charge, drug loading, and morphological attributes. The efficacy was evaluated by in vitro MTT studies, safety by erythrocyte compatibility, and biodistribution by in vivo pharmacokinetic studies. Despite better drug loading and sustained drug release, cytotoxicity on MCF-7 breast cancer cells was substantially enhanced and the pharmacokinetic profile was significantly modified. The AUC was enhanced manifolds along with reduced clearance. The findings are unique and provide an alternative to the conventional lipid-based nanocarriers for better dose delivery, tissue adhesion, and desired pharmacokinetic modulation. 相似文献
998.
Eric E. Lopez-Vera Sarah Nelson Ravi P. Singh Bhoja R. Basnet Scott D. Haley Sridhar Bhavani Julio Huerta-Espino Beatriz G. Xoconostle-Cazares Roberto Ruiz-Medrano Matthew N. Rouse Sukhwinder Singh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(1):231-239
Key message
Identified SSR markers ( Xcfd49 and Xbarc183 ) linked with stem rust resistance for efficient use in marker-assisted selection and stacking of resistance genes in wheat breeding programs.Abstract
More than 80 % of the worldwide wheat (Triticum aestivum L.) area is currently sown with varieties susceptible to the Ug99 race group of stem rust fungus. However, wheat lines Niini, Tinkio, Coni, Pfunye, Blouk, and Ripper have demonstrated Ug99 resistance at the seedling and adult plant stages. We mapped stem rust resistance in populations derived from crosses of a susceptible parent with each of the resistant lines. The segregation of resistance in each population indicated the presence of a single gene. The resistance gene in Niini mapped to short arm of chromosome 6D and was flanked by SSR markers Xcfd49 at distances of 3.9 cM proximal and Xbarc183 8.4 cM distal, respectively. The chromosome location of this resistance was validated in three other populations: PBW343/Coni, PBW343/Tinkio, and Cacuke/Pfunye. Resistance initially postulated to be conferred by the SrTmp gene in Blouk and Ripper was also linked to Xcfd49 and Xbarc183 on 6DS, but it was mapped proximal to Xbarc183 at a similar position to previously mapped genes Sr42 and SrCad. Based on the variation in diagnostic marker alleles, it is possible that Niini and Pfunye may carry different resistance genes/alleles. Further studies are needed to determine the allelic relationships between various genes located on chromosome arm 6DS. Our results provide valuable molecular marker and genetic information for developing Ug99 resistant wheat varieties in diverse germplasm and using these markers to tag the resistance genes in wheat breeding. 相似文献999.
1000.
Nicola Aceto Aditya Bardia David T. Miyamoto Maria C. Donaldson Ben S. Wittner Joel A. Spencer Min Yu Adam Pely Amanda Engstrom Huili Zhu Brian W. Brannigan Ravi Kapur Shannon L. Stott Toshi Shioda Sridhar Ramaswamy David T. Ting Charles P. Lin Mehmet Toner Daniel A. Haber Shyamala Maheswaran 《Cell》2014