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51.
Dinesh Mondal Murari Lal Das Vijay Kumar M. Mamun Huda Pradeep Das Debashis Ghosh Jyoti Priyanka Greg Matlashewski Axel Kroeger Alexander Upfill-Brown Rajib Chowdhury 《PLoS neglected tropical diseases》2016,10(8)
BackgroundWe investigated the efficacy, safety and cost of lime wash of household walls plus treatment of sand fly breeding places with bleach (i.e. environmental management or EM), insecticide impregnated durable wall lining (DWL), and bed net impregnation with slow release insecticide (ITN) for sand fly control in the Indian sub-continent.MethodsThis multi-country cluster randomized controlled trial had 24 clusters in each three sites with eight clusters per high, medium or low sand fly density stratum. Every cluster included 45–50 households. Five households from each cluster were randomly selected for entomological measurements including sand fly density and mortality at one, three, nine and twelve months post intervention. Household interviews were conducted for socioeconomic information and intervention acceptability assessment. Cost for each intervention was calculated. There was a control group without intervention.FindingsSand fly mortality [mean and 95%CI] ranged from 84% (81%-87%) at one month to 74% (71%-78%) at 12 months for DWL, 75% (71%-79%) at one month to 49% (43%-55%) at twelve months for ITN, and 44% (34%-53%) at one month to 22% (14%-29%) at twelve months for EM. Adjusted intervention effect on sand fly density measured by incidence rate ratio ranged from 0.28 (0.23–0.34) at one month to 0.62 (0.51–0.75) at 12 months for DWL; 0.72 (0.62–0.85) at one month to 1.02 (0.86–1.22) at 12 months for ITN; and 0.89 (0.76–1.03) at one months to 1.49 (1.26–1.74) at 12 months for EM. Household acceptance of EM was 74% compared to 94% for both DWL and ITN. Operational cost per household in USD was about 5, 8, and 2 for EM, DWL and ITN, respectively. Minimal adverse reactions were reported for EM and ITN while 36% of households with DWL reported transient itching.InterpretationDWL is the most effective, durable and acceptable control method followed by ITN. The Visceral Leishmaniasis (VL) Elimination Program in the Indian sub-continent should consider DWL and ITN for sand fly control in addition to IRS. 相似文献
52.
Sandipan Roy Chowdhury Steven Kennedy Kai Zhu Rama Mishra Patrick Chuong Alyssa-uyen Nguyen Stefan G. Kathman Alexander V. Statsyuk 《Bioorganic & medicinal chemistry letters》2019,29(1):36-39
Here we present a virtual docking screen of 1648 commercially available covalent fragments, and identified covalent inhibitors of cysteine protease cathepsin L. These inhibitors did not inhibit closely related protease cathepsin B. Thus, we have established virtual docking of covalent fragments as an approach to discover covalent enzyme inhibitors. 相似文献
53.
Plasma Physics Reports - Modulational instability (MI) of ion-acoustic waves (IAWs) has been theoretically investigated in a plasma system which is composed of inertial warm adiabatic ions,... 相似文献
54.
Soumitra Paul Chowdhury Doreen Babin Martin Sandmann Samuel Jacquiod Loreen Sommermann Søren Johannes Sørensen Andreas Fliessbach Paul Mäder Joerg Geistlinger Kornelia Smalla Michael Rothballer Rita Grosch 《Environmental microbiology》2019,21(7):2426-2439
Long-term agricultural fertilization strategies gradually change soil properties including the associated microbial communities. Cultivated crops recruit beneficial microbes from the surrounding soil environment via root exudates. In this study, we aimed to investigate the effects of long-term fertilization strategies across field sites on the rhizosphere prokaryotic (Bacteria and Archaea) community composition and plant performance. We conducted growth chamber experiments with lettuce (Lactuca sativa L.) cultivated in soils from two long-term field experiments, each of which compared organic versus mineral fertilization strategies. 16S rRNA gene amplicon sequencing revealed the assemblage of a rhizosphere core microbiota shared in all lettuce plants across soils, going beyond differences in community composition depending on field site and fertilization strategies. The enhanced expression of several plant genes with roles in oxidative and biotic stress signalling pathways in lettuce grown in soils with organic indicates an induced physiological status in plants. Lettuce plants grown in soils with different fertilization histories were visibly free of stress symptoms and achieved comparable biomass. This suggests a positive aboveground plant response to belowground plant–microbe interactions in the rhizosphere. Besides effects of fertilization strategy and field site, our results demonstrate the crucial role of the plant in driving rhizosphere microbiota assemblage. 相似文献
55.
Indrajit Chowdhury Saswati Banerjee Adel Driss Wei Xu Sherifeh Mehrabi Ceana Nezhat Neil Sidell Robert N. Taylor Winston E. Thompson 《Journal of cellular physiology》2019,234(5):6298-6312
Endometriosis is a chronic gynecological inflammatory disorder in which immune system dysregulation is thought to play a role in its initiation and progression. Due to altered sex steroid receptor concentrations and other signaling defects, eutopic endometriotic tissues have an attenuated response to progesterone. This progesterone-resistance contributes to lesion survival, proliferation, pain, and infertility. The current agency-approved hormonal therapies, including synthetic progestins, GnRH agonists, and danazol are often of limited efficacy and counterproductive to fertility and cause systemic side effects due to suppression of endogenous steroid hormone levels. In the current study, we examined the effects of curcumin (CUR, diferuloylmethane), which has long been used as an anti-inflammatory folk medicine in Asian countries for this condition. The basal levels of proinflammatory and proangiogenic chemokines and cytokines expression were higher in primary cultures of stromal cells derived from eutopic endometrium of endometriosis (EESC) subjects compared with normal endometrial stromal cells (NESC). The treatment of EESC and NESC with CUR significantly and dose-dependently reduced chemokine and cytokine secretion over the time course. Notably, CUR treatment significantly decreased phosphorylation of the IKKα/β, NF-κB, STAT3, and JNK signaling pathways under these experimental conditions. Taken together, our findings suggest that CUR has therapeutic potential to abrogate aberrant activation of chemokines and cytokines, and IKKα/β, NF-κB, STAT3, and JNK signaling pathways to reduce inflammation associated with endometriosis. 相似文献
56.
Debapriya De Priyanka Chowdhury Sujogya K. Panda Utpal Ghosh 《Journal of cellular biochemistry》2019,120(12):19841-19857
Despite the advancement of the pharmaceutical industry, medicinal plants are still a reliable source of traditional medicines to cure a number of diseases. Various parts of Dillenia pentagyna are used in traditional medicine in India for treatment of various disorders including cancers, but detailed mechanisms are still unknown. Dried leaves of D. pentagyna were extracted with ethanol and termed as an ethanolic extract of leaves of D. pentagyna (EELDP). Our aim was to elucidate the role of EELDP in in-vitro cell migration and apoptosis in highly metastatic human lung adenocarcinoma A549 cells. We measured cell viability and in-vitro cell migration in three different human cancer cells A549, HeLa and U2OS treated with EELDP (0-0.6 mg/mL). However, A549 cells showed higher sensitivity to EELDP treatment. Hence we studied several key markers of metastasis and apoptosis pathway in A549 cells treated with EELDP. EELDP treatment significantly reduced in-vitro cell migration, wound healing, expression and activity of MMP-2, MMP-9 via reduction of nuclear factor kappa Beta (NF-κβ). EELDP also reduced vimentin, N-cadherin and increased claudin-1. The intrinsic pathway of apoptosis was triggered by EELDP via the NF-κβ pathway through the increase of the Bax to Bcl2 ratio, leading to the fall of mitochondrial membrane potential and subsequently induced release of cytochrome c, activation of caspase-3 followed by nuclear fragmentation in A549 cells. Furthermore, we observed change of a few markers of metastasis and apoptosis in other two cell types HeLa and U2OS treated with EELDP. These data implicate that the effect of EELDP is not cell-specific. Since only 0.1 mg/mL EELDP significantly reduces in-vitro cell migration and increases apoptosis, the active compound(s) present in EELDP is very much potent to control highly metastatic cancer. 相似文献
57.
58.
Dynamic compression inhibits the synthesis of nitric oxide and PGE(2) by IL-1beta-stimulated chondrocytes cultured in agarose constructs 总被引:2,自引:0,他引:2
Chowdhury TT Bader DL Lee DA 《Biochemical and biophysical research communications》2001,285(5):1168-1174
Both mechanical loading and interleukin-1beta (IL-1beta) are known to regulate metabolic processes in articular cartilage through pathways mediated by nitric oxide ((*)NO) and PGE(2). This study uses a well-characterized model system involving isolated chondrocytes cultured in agarose constructs to test the hypothesis that dynamic compression alters the synthesis of (*)NO and PGE(2) by IL-1beta-stimulated articular chondrocytes. The data presented demonstrate for the first time that dynamic compression counteracts the effects of IL-1beta on articular chondrocytes by suppressing both (*)NO and PGE(2) synthesis. Inhibitor experiments indicated that the dynamic compression-induced inhibition of PGE(2) synthesis and stimulation of proteoglycan synthesis were (*)NO mediated, while compression-induced stimulation of cell proliferation was (*)NO independent. The inhibition of (*)NO and PGE(2) by dynamic compression is a finding of major significance that could contribute to the development of novel strategies for the treatment of cartilage-degenerative disorders. 相似文献
59.
Homodimerization of human bilirubin-uridine-diphosphoglucuronate glucuronosyltransferase-1 (UGT1A1) and its functional implications 总被引:1,自引:0,他引:1
Ghosh SS Sappal BS Kalpana GV Lee SW Chowdhury JR Chowdhury NR 《The Journal of biological chemistry》2001,276(45):42108-42115
Genetic lesions of bilirubin-uridine-diphosphoglucuronate glucuronosyltransferase-1 (UGT1A1) completely or partially abolish hepatic bilirubin glucuronidation, causing Crigler-Najjar syndrome type 1 or 2, respectively. Clinical observations indicate that some mutant forms of human UGT1A1 (hUGT1A1) may be dominant-negative, suggesting their interaction with the wild-type enzyme. To evaluate intermolecular interaction of hUGT1A1, Gunn rat fibroblasts were stably transduced with hUGT1A1 cDNA. Gel permeation chromatography of solubilized microsomes suggested dimerization of hUGT1A1 in solution. Nearest-neighbor cross-linking analysis indicated that, within microsomal membranes, hUGT1A1 dimerized more efficiently at pH 7.4 than at pH 9. Two-hybrid analysis in yeast and mammalian systems demonstrated positive interaction of hUGT1A1 with itself, but not with another UGT isoform, human UGT1A6, which differs only in the N-terminal domain. Dimerization was abolished by deletion of the membrane-embedded helix from the N-terminal domain of hUGT1A1, but not by substitution of several individual amino acid residues or partial deletion of the C-terminal domain. A C127Y substitution abolished UGT1A1 activity, but not its dimerization. Coexpression of mutagenized and wild-type hUGT1A1 in COS-7 cells showed that the mutant form markedly suppressed the catalytic activity of wild-type hUGT1A1. Homodimerization of hUGT1A1 may explain the dominant-negative effect of some mutant forms of the enzyme. 相似文献
60.
Chowdhury S Thomas MG Escalante-Semerena JC Banerjee R 《The Journal of biological chemistry》2001,276(2):1015-1019
Methylmalonyl-CoA mutase is an 5'-adenosylcobalamin (AdoCbl)-dependent enzyme that catalyzes the rearrangement of methylmalonyl-CoA to succinyl-CoA. The crystal structure of this protein revealed that binding of the cofactor is accompanied by a significant conformational change in which dimethylbenzimidazole, the lower axial ligand to cobalt in solution, is replaced by His(610) donated by the active site. The role of the lower axial ligand in the trillion-fold labilization of the upper axial cobalt-carbon bond has been the subject of enduring debate in the model inorganic literature. In this study, we have used a cofactor analog, 5'deoxyadenosylcobinamide GDP (AdoCbi-GDP), which reconstitutes the enzyme in a "histidine-off" form and which allows us to evaluate the contribution of the lower axial ligand to catalysis. The k(cat) for the enzyme in the presence of AdoCbi-GDP is reduced by a factor of 4 compared with the native cofactor AdoCbl. The overall deuterium isotope effect in the presence of AdoCbi-GDP ((D)V = 7.2 +/- 0.8) is comparable with that observed in the presence of AdoCbl (5.0 +/- 0.6) and indicates that the hydrogen transfer steps in this reaction are not significantly affected by the change in coordination state of the bound cofactor. These surprising results are in marked contrast to the effects ascribed to the corresponding lower axial histidine ligands in the cobalamin-dependent enzymes glutamate mutase and methionine synthase. 相似文献