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191.
Establishment of early pregnancy is promoted by a complex network of signalling molecules that mediate cell-to-cell and cell-to-extracellular matrix communications between the receptive endometrium and the invasive trophectoderm. In this study, we have attempted to evaluate the expression profiles of cadherin and catenin during embryo implantation in the mouse. Western blotting studies along with immunocytochemical analysis revealed that E-cadherin is expressed rather ubiquitously in the uterine epithelial cells, distinct enrichment is observed on the apical membrane in the endometrium of peri-implantation uterus specifically at the implantation sites and not at the inter-implanation sites. beta-Catenin also is upregulated and is specifically restricted to apical membrane of epithelial cells of implantation sites. Progesterone induced expression of E-cadherin and 17beta-estradiol regulated the expression of catenin in implantation-delayed uteri. Interestingly, estradiol imparted negative modulation on cadherin expression when co-administered with progesterone. On the contrary, trophoblast exhibits a striking down regulation of cadherin, catenin and Ca(2+) at peri implanting stage. These observations suggest that the trophoblasts exhibited an invasive phenotype while the endometrial epithelium displayed an adhesive phenotype during the window of implantation. Thus, embryo implantation presents an instance where two interacting surfaces showed mutually complementing interaction phenotypes. 相似文献
192.
Bora NS Kaliappan S Jha P Xu Q Sohn JH Dhaulakhandi DB Kaplan HJ Bora PS 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(3):1872-1878
The objective of this study was to explore the role of classical, lectin, and alternative pathways of complement activation in laser-induced choroidal neovascularization (CNV). The classical and alternative pathways were blocked in C57BL/6 mice by small interfering RNAs (siRNA) directed against C1q and factor B, respectively. C4(-/-) mice developed CNV similar to their wild-type controls and inhibition of C1q by siRNA had no effect on the development of CNV. In contrast, CNV was significantly inhibited (p < 0.001) in C5(-/-) mice and C57BL/6 mice treated with factor B siRNA. Inhibition of the alternative pathway by factor B siRNA resulted in decreased levels of membrane attack complex and angiogenic factors-vascular endothelial growth factor and TGF-beta2. Furthermore, factor B was up-regulated in complement sufficient C57BL/6 mice at day 1 postlaser and remained elevated at day 7. Significantly reduced levels of factor H were observed at day 3 in these animals. In conclusion, our results demonstrate that activation of the factor B-dependent alternative pathway, but not the classical or lectin pathways, was essential for the development of CNV in mouse model of laser-induced CNV. Thus, specific blockade of the alternative pathway may represent a therapeutically relevant strategy for the inhibition of CNV. 相似文献
193.
Molinaro RJ Jha BK Malathi K Varambally S Chinnaiyan AM Silverman RH 《Nucleic acids research》2006,34(22):6684-6695
The antiviral and antitumor functions of RNase L are enabled by binding to the allosteric effectors 5′-phosphorylated, 2′,5′-linked oligoadenylates (2-5A). 2-5A is produced by interferon-inducible 2′,5′-oligoadenylate synthetases (OAS) upon activation by viral double-stranded RNA (dsRNA). Because mutations in RNase L have been implicated as risk factors for prostate cancer, we sought to determine if OAS activators are present in prostate cancer cells. We show that prostate cancer cell lines (PC3, LNCaP and DU145), but not normal prostate epithelial cells (PrEC), contain RNA fractions capable of binding to and activating OAS. To identify the RNA activators, we developed a cDNA cloning strategy based on stringent affinity of RNAs for OAS. We thus identified mRNAs for Raf kinase inhibitor protein (RKIP) and poly(rC)-binding protein 2 (PCBP2) that bind and potently activate OAS. In addition, human endogenous retrovirus (hERV) envelope RNAs were present in PC3 cells that bind and activate OAS. Analysis of several gene expression profiling studies indicated that PCBP2 RNA was consistently elevated in metastatic prostate cancer. Results suggest that OAS activation may occur in prostate cancer cells in vivo stimulated by cellular mRNAs for RKIP and PCBP2. 相似文献
194.
The present work deals with the biosorption performance of raw and chemically modified biomass of the brown seaweed Lobophora variegata for removal of Cd(II) and Pb(II) from aqueous solution. The biosorption capacity was significantly altered by pH of the solution
delineating that the higher the pH, the higher the Cd(II) and Pb(II) removal. Kinetic and isotherm experiments were carried
out at the optimal pH 5.0. The metal removal rates were conspicuously rapid wherein 90% of the total sorption occurred within
90 min. Biomass treated with CaCl2 demonstrated the highest potential for the sorption of the metal ions with the maximum uptake capacities i.e. 1.71 and 1.79 mmol g−1 for Cd(II) and Pb(II), respectively. Kinetic data were satisfactorily manifested by a pseudo-second order chemical sorption
process. The process mechanism consisting of both surface adsorption and pore diffusion was found to be complex. The sorption
data have been analyzed and fitted to sorption isotherm of the Freundlich, Langmuir, and Redlich–Peterson models. The regression
coefficient for both Langmuir and Redlich–Peterson isotherms were higher than those secured for Freundlich isotherm implying
that the biosorption system is possibly monolayer coverage of the L. variegata surface by the cadmium and lead ions. FT-IR studies revealed that Cd(II) and Pb(II) binding to L. variegata occurred primarily through biomass carboxyl groups accompanied by momentous interactions of the biomass amino and amide groups.
In this study, we have observed that L. variegata had maximum biosorption capacity for Cd(II) and Pb(II) reported so far for any marine algae.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
195.
Babita Kumari Jha Mohandass Gandhi Pragash Jean Cletus Gurusamy Raman Natarajan Sakthivel 《World journal of microbiology & biotechnology》2009,25(4):573-581
Of 80 fluorescent pseudomonad strains screened for phosphate solubilization, three strains (BFPB9, FP12 and FP13) showed the
ability to solubilize tri-calcium phosphate (Ca3(PO4)2). During mineral phosphate solubilization, decrease of pH in the culture medium due to the production of organic acids by
the strains was observed. These phosphate solubilizing strains produced indole-3-acetic acid (IAA) and protease as well as
exhibited a broad-spectrum antifungal activity against phytopathogenic fungi. When tested in PCR using the gene-specific primers,
strain BFPB9 showed the presence of hcnBC genes that encode hydrogen cyanide. On the basis of phenotypic traits, 16S rRNA sequence homology and subsequent phylogenetic
analysis, strains BFPB9, FP12 and FP13 were designated as Pseudomonas aeruginosa, P. plecoglossicida and P. mosselii, respectively. Present investigation reports the phosphate solubilization potential and biocontrol ability of new strains
that belong to P. plecoglossicida and P. mosselii. Because of the innate potential of phosphate solubilization, production of siderophore, IAA, protease, cellulase and HCN
strains reported in this study can be used as biofertilizers as well as biocontrol agents. 相似文献
196.
We isolated nine microsatellite loci from the Neotropical understorey tree Miconia affinis (Melastomataceae) and optimized them for research on gene flow and genetic structure. Loci screened in 43 individuals from a 2.26-km(2) region were shown to be unlinked and polymorphic, with 5 to 14 alleles per locus and observed heterozygosity ranging from 0.394 to 0.810. 相似文献
197.
Pushpa Malla Elisabeth Eva Kanitz Mohammad Akhtar Dennis Falzon Knut Feldmann Christian Gunneberg Shyam Sundar Jha Bhagwan Maharjan Mohan Kumar Prasai Bhabana Shrestha Sharat Chandra Verma Matteo Zignol 《PloS one》2009,4(12)
Objective
The aim of this study was to describe treatment outcomes for multi-drug resistant tuberculosis (MDR-TB) outpatients on a standardized regimen in Nepal.Methodology
Data on pulmonary MDR-TB patients enrolled for treatment in the Green Light Committee-approved National Programme between 15 September 2005 and 15 September 2006 were studied. Standardized regimen was used (8Z-Km-Ofx-Eto-Cs/16Z-Ofx-Eto-Cs) for a maximum of 32 months and follow-up was by smear and culture. Drug susceptibility testing (DST) results were not used to modify the treatment regimen. MDR-TB therapy was delivered in outpatient facilities for the whole course of treatment. Multivariable analysis was used to explain bacteriological cure as a function of sex, age, initial body weight, history of previous treatment and the region of report.Principal Findings
In the first 12-months, 175 laboratory-confirmed MDR-TB cases (62% males) had outcomes reported. Most cases had failed a Category 2 first-line regimen (87%) or a Category 1 regimen (6%), 2% were previously untreated contacts of MDR-TB cases and 5% were unspecified. Cure was reported among 70% of patients (range 38%–93% by Region), 8% died, 5% failed treatment, and 17% defaulted. Unfavorable outcomes were not correlated to the number of resistant drugs at baseline DST. Cases who died had a lower mean body weight than those surviving (40.3 kg vs 47.2 kg, p<0.05). Default was significantly higher in two regions [Eastern OR = 6.2; 95%CL2.0-18.9; Far West OR = 5.0; 95%CL1.0-24.3]. At logistic regression, cure was inversely associated with body weight <36 kg [Adj.OR = 0.1; 95%CL0.0-0.3; ref. 55–75 kg] and treatment in the Eastern region [Adj.OR = 0.1; 95%CL0.0-0.4; ref. Central region].Conclusions
The implementation of an ambulatory-based treatment programme for MDR-TB based on a fully standardized regimen can yield high cure rates even in resource-limited settings. The determinants of unfavorable outcome should be investigated thoroughly to maximize likelihood of successful treatment. 相似文献198.
Chhillar AK Arya P Mukherjee C Kumar P Yadav Y Sharma AK Yadav V Gupta J Dabur R Jha HN Watterson AC Parmar VS Prasad AK Sharma GL 《Bioorganic & medicinal chemistry》2006,14(4):973-981
Ten 4-aryl-1,4-dihydropyridine and three 4-aryl-1,2,3,4-tetrahydropyrimidin-2-one derivatives have been synthesized and examined for their activity against pathogenic strains of Aspergillus fumigatus and Candida albicans. Although none of the three compounds belonging to pyrimidin-2-one series showed any activity against two pathogens, two of the compounds of the dihydropyridine series, that is, diethyl 4-(4-methoxyphenyl)-2,6-dimethyl-1,4-dihydropyridin-3,5-dicarboxylate and dimethyl 4-(4-methoxyphenyl)-2,6-dimethyl-1,4-dihydropyridin-3,5-dicarboxylate, exhibited significant activity against A. fumigatus in disc diffusion, microbroth dilution and percent spore germination inhibition assays. The most active diethyl dihydropyridine derivative exhibited a MIC value of 2.92 microg/disc in disc diffusion and 15.62 microg/ml in microbroth dilution assays. The MIC(90) value of the most active compound by percent germination inhibition assay was found to be 15.62 microg/ml. The diethyl dicarboxylate derivative of dihydropyridine also exhibited appreciable activity against C. albicans. The in vitro toxicity of the most active diethyl dihydropyridine derivative was evaluated using haemolytic assay, in which the compound was found to be non-toxic to human erythrocytes even at a concentration of 625 microg/ml. The standard drug amphotericin B exhibited 100% lysis of erythrocytes at a concentration almost 16 times less than the safer concentration of the most active dihydropyridine derivative. 相似文献
199.