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Roopa NilamberLal Das Sridevi Muruhan Rajendra Prasad Nagarajan Agilan Balupillai 《Journal of biochemical and molecular toxicology》2019,33(3)
The present study, we investigate the preventive role of naringin, a dietary flavonoid, against ultraviolet‐B (UVB) radiation (280‐320 nm) induced oxidative damage and inflammatory responses in mouse embryonic fibroblast cell lines (NIH‐3T3). In this study, 20 mJ/cm 2 of UVB radiation induces cell cytotoxicity, reactive oxygen species (ROS) generation, DNA damage, and antioxidants depletion in NIH‐3T3 cells. Treatment with naringin (60 µM) prior UVB exposure prevented the cell cytotoxicity, ROS generation, DNA damage, and antioxidants depletion in NIH‐3T3 cells. Furthermore, naringin prevents UVB‐induced mitogen‐activated protein kinase families and nuclear factor‐κB (NF‐κB)‐mediated activation of inflammatory factors, that is TNF‐α, IL‐6, IL‐10, and COX‐2 in NIH‐3T3 cells. Peroxisome proliferator‐activated receptor γ (PPARγ) is an anti‐inflammatory agent and it suppressed the UVB‐mediated oxidative and inflammatory responses. In this study, naringin activates PPARγ and prevents inflammatory biomarkers in NIH‐3T3 cells. Thus, naringin prevents UVB‐mediated inflammation and oxidative damage in NIH‐3T3 cells probably over controlling NF‐κB expression and activation of PPARγ. 相似文献
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Hedgehog is required for murine yolk sac angiogenesis. 总被引:13,自引:0,他引:13
Noah Byrd Sandy Becker Peter Maye Roopa Narasimhaiah Benoit St-Jacques Xiaoyan Zhang Jill McMahon Andrew McMahon Laura Grabel 《Development (Cambridge, England)》2002,129(2):361-372
Blood islands, the precursors of yolk sac blood vessels, contain primitive erythrocytes surrounded by a layer of endothelial cells. These structures differentiate from extra-embryonic mesodermal cells that underlie the visceral endoderm. Our previous studies have shown that Indian hedgehog (Ihh) is expressed in the visceral endoderm both in the visceral yolk sac in vivo and in embryonic stem (ES) cell-derived embryoid bodies. Differentiating embryoid bodies form blood islands, providing an in vitro model for studying vasculogenesis and hematopoiesis. A role for Ihh in yolk sac function is suggested by the observation that roughly 50% of Ihh(-/-) mice die at mid-gestation, potentially owing to vascular defects in the yolk sac. To address the nature of the possible vascular defects, we have examined the ability of ES cells deficient for Ihh or smoothened (Smo), which encodes a receptor component essential for all hedgehog signaling, to form blood islands in vitro. Embryoid bodies derived from these cell lines are unable to form blood islands, and express reduced levels of both PECAM1, an endothelial cell marker, and alpha-SMA, a vascular smooth muscle marker. RT-PCR analysis in the Ihh(-/-) lines shows a substantial decrease in the expression of Flk1 and Tal1, markers for the hemangioblast, the precursor of both blood and endothelial cells, as well as Flt1, an angiogenesis marker. To extend these observations, we have examined the phenotypes of embryo yolk sacs deficient for Ihh or SMO: Whereas Ihh(-/-) yolk sacs can form blood vessels, the vessels are fewer in number and smaller, perhaps owing to their inability to undergo vascular remodeling. Smo(-/-) yolk sacs arrest at an earlier stage: the endothelial tubes are packed with hematopoietic cells, and fail to undergo even the limited vascular remodeling observed in the Ihh(-/-) yolk sacs. Our study supports a role for hedgehog signaling in yolk sac angiogenesis. 相似文献
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Nripendra Vikram Singh Shilpa Parashuram Jyotsana Sharma Roopa Sowjanya Potlannagari Dhinesh Babu Karuppannan Ram Krishna Pal Prakash Patil Dhananjay M. Mundewadikar Vipul R. Sangnure P.V. Parvati Sai Arun Naresh V.R. Mutha Bipin Kumar Abhishek Tripathi Sathish Kumar Peddamma Harish Kothandaraman Sailu Yellaboina Dushyant Singh Baghel Umesh K. Reddy 《Saudi Journal of Biological Sciences》2020,27(12):3514-3528
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Tooba Naz Shamsi Romana Parveen Afaque Ahmad Roopa Rani Samal Sarita Kumar Sadaf Fatima 《农业工程》2018,38(5):325-328
The paper describes the bio efficacy of a protease inhibitor; isolated from Allium sativum ‘garlic’ (ASPI); against Aedes aegypti mosquito, a well-known transmitter of dengue and Chikungunya. The purification of protease inhibitor from Allium sativum ‘garlic’ (ASPI) was carried out by ammonium sulfate precipitation followed by Fast Protein Liquid Chromatography using akta DEAE-Cellulose column. The protein fraction demonstrating trypsin inhibitory activity was further evaluated for its insecticidal activity using gut protease inhibition assay and larvicidal assay. ASPI is an inhibitor of porcine trypsin (IC50 of 650.726?μg/mL) and has molecular weight of ~15?kDa determined by SDS PAGE similar to other inhibitors of the Kunitz-type family (14–26?kDa). ASPI demonstrated 50% reduced activity of Ae. aegypti midgut proteases and showed a dose-dependent acute toxicity on Ae. aegypti 3rd instars exhibiting LC50 value of ~50.827?μg/mL. After ten days of larval exposure ASPI resulted in a 24-h delay of larval development and ~72% mortality at 61.5?μg/mL. These results suggest that ASPI may serve as potent insecticidal agent and hence opens a new gateway in the field of phyto-remediation. 相似文献
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Reddy BV Rajeswari N Sarangapani M Roopa Reddy G Madan Ch Pranay Kumar K Srinivasa Rao M 《Bioorganic & medicinal chemistry letters》2011,21(21):6510-6514
Indole and its derivatives undergo smooth conjugate addition onto en-1,4-dione derived from isatin and acetophenone, in the presence of a catalytic amount of molecular iodine in acetonitrile under mild conditions to afford a novel class of 3-(1-(1H-indol-3-yl)-2-oxo-2-phenylethyl)indolin-2-one derivatives in good yields with high degree of 1,4-selectivity. Some of these compounds are found to exhibit modest antibacterial and antifungal properties. 相似文献
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Substrate-induced conformational changes in Plasmodium falciparum guanosine monophosphate synthetase
GMP synthetase is a glutamine amidotransferase that incorporates ammonia derived from glutamine into the nucleotide xanthosine 5'-monophosphate (XMP) to form guanosine 5'-monophosphate (GMP). Functional coordination of domains in glutamine amidotransferases leads to upregulation of glutamine hydrolysis in the presence of acceptor substrates and is a common feature in this class of enzymes. We have shown earlier that binding of substrates to the acceptor domain of Plasmodium falciparum GMP synthetase (PfGMPS) leads to enhancement in both glutaminase activity and rate of glutaminase inactivation, by the irreversible inhibitors acivicin and diazo-oxonorleucine [Bhat JY et al. (2008) Biochem J409, 263-273], a process that must be driven by conformational alterations. In this paper, through the combined use of biochemical assays, optical spectroscopy and mass spectrometry, we demonstrate that PfGMPS undergoes conformational transitions upon binding of substrates to the acceptor domain. Limited proteolysis and hydrogen-deuterium exchange in conjunction with mass spectrometry unveil region-specific conformational changes in the ATP + XMP bound state of PfGMPS. Decreased accessibility of R294 and K428 residues to trypsin in the ATP pyrophosphatase domain and reduced deuterium incorporation in the 143-155 region, pertaining to the glutaminase domain, suggest that in PfGMPS ligand-induced conformational changes are not only local but also transmitted over a long range across the domains. Overall, these results provide a detailed understanding of the substrate-induced changes in PfGMPS that could be essential for the overall catalytic process. 相似文献
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Vimaleswaran KS Radha V Ramya K Babu HN Savitha N Roopa V Monalisa D Deepa R Ghosh S Majumder PP Rao MR Mohan V 《Human genetics》2008,123(6):599-605
Adiponectin is an adipose tissue specific protein that is decreased in subjects with obesity and type 2 diabetes. The objective
of the present study was to examine whether variants in the regulatory regions of the adiponectin gene contribute to type
2 diabetes in Asian Indians. The study comprised of 2,000 normal glucose tolerant (NGT) and 2,000 type 2 diabetic, unrelated
subjects randomly selected from the Chennai Urban Rural Epidemiology Study (CURES), in southern India. Fasting serum adiponectin
levels were measured by radioimmunoassay. We identified two proximal promoter SNPs (−11377C→G and −11282T→C), one intronic
SNP (+10211T→G) and one exonic SNP (+45T→G) by SSCP and direct sequencing in a pilot study (n = 500). The +10211T→G SNP alone was genotyped using PCR-RFLP in 4,000 study subjects. Logistic regression analysis revealed
that subjects with TG genotype of +10211T→G had significantly higher risk for diabetes compared to TT genotype [Odds ratio
1.28; 95% Confidence Interval (CI) 1.07–1.54; P = 0.008]. However, no association with diabetes was observed with GG genotype (P = 0.22). Stratification of the study subjects based on BMI showed that the odds ratio for obesity for the TG genotype was
1.53 (95%CI 1.3–1.8; P < 10−7) and that for GG genotype, 2.10 (95% CI 1.3–3.3; P = 0.002). Among NGT subjects, the mean serum adiponectin levels were significantly lower among the GG (P = 0.007) and TG (P = 0.001) genotypes compared to TT genotype. Among Asian Indians there is an association of +10211T→G polymorphism in the
first intron of the adiponectin gene with type 2 diabetes, obesity and hypoadiponectinemia. 相似文献
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The infection by Salmonella enterica results in the massive remodeling of the endosomal system of eukaryotic host cells. One unique consequence is the formation of long tubular endosomal compartments, so-called Salmonella-induced filaments (SIF). Formation of SIF requires the function of type III secretion system and is a requirement of efficient intracellular proliferation of Salmonella. Using high-resolution live cell imaging approaches and electron microscopy, we report for the first time the highly dynamic characteristics of SIF and their ultrastructural properties. In the early phase of infection (4-5 h), SIF display highly dynamic properties in various types of host cells. SIF extend, branch and contract rapidly, and a stabilized network of SIF is formed later (>or=8 h after infection). The velocities of SIF extension and contraction in the different phases of infection were quantified. Our observations lead to novel models for the modification of host cell transport processes by virulence factors of intracellular Salmonella. 相似文献