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81.
82.
Ghosh Abhijit Pechota L. V. T. Angela Upchurch Gilbert R. Eliason Jonathan L. 《Molecular and cellular biochemistry》2015,406(1-2):75-81
The aim of the present study was to analyze the expression of sex-determining region Y-related high mobility group box 4 (SOX4) in non-small cell lung cancer (NSCLC) and its correlation with clinicopathologic characteristics, including the survival of NSCLC patients. To observe initially the expression status of SOX4 in lung squamous cell carcinoma and adenocarcinoma at gene expression omnibus. The expression of SOX4 mRNA and protein was examined in NSCLC tissues and normal lung tissues through real-time PCR and immunohistochemistry. Meanwhile, the relationship of SOX4 expression levels with clinical characteristics of 168 NSCLC patients was analyzed by immunohistochemistry. Univariate and multivariate analyses were performed to determine the association between SOX4 expression and prognosis of NSCLC patients. In our results, SOX4 expression was increased in NSCLC tissues compared with paired normal lung tissues in microarray data (GSE3268). SOX4 mRNA and protein expression were markedly higher in NSCLC tissues than in normal lung tissues (P = 0.001 and P = 0.001, respectively). Using immunohistochemistry, high levels of SOX4 protein were positively correlated with status of differentiated degree (high vs. middle, P = 0.004; high vs. low, P < 0.001), clinical stage (I–II vs. III–IV, P < 0.001), T classification (T1–T2 vs. T3–T4, P = 0.004), N classification (N0–N1 vs. N2–N3, P = 0.002), and M classification (M0 vs. M1, P = 0.011) in NSCLC. Moreover, the higher level of SOX4 expression was markedly correlated with poor overall survival in NSCLC patients (P < 0.001). Multivariate analysis suggested that increased SOX4 expression was a poor independent prognostic predictor for NSCLC patients (P = 0.002). In conclusion, SOX4 plays an important role on NSCLC progression and prognosis and may serve as a convictive prognostic biomarker for NSCLC patients. 相似文献
83.
Kanika Narula Pooja Choudhary Sudip Ghosh Eman Elagamey Niranjan Chakraborty Subhra Chakraborty 《Proteomics》2019,19(3)
Modulation of plant immune system by extrinsic/intrinsic factors and host‐specific determinants fine‐tunes cellular components involving multiple organelles, particularly nucleus to mount resistance against pathogen attack. Rice blast, caused by hemibiotrophic fungus Magnaporthe oryzae, is one of the most devastating diseases that adversely affect rice productivity. However, the role of nuclear proteins and their regulation in response to M. oryzae remains unknown. Here, the nucleus‐associated immune pathways in blast‐resistant rice genotype are elucidated. Temporal analysis of nuclear proteome is carried out using 2‐DE coupled MS/MS analysis. A total of 140 immune responsive proteins are identified associated with nuclear reorganization, cell division, energy production/deprivation, signaling, and gene regulation. The proteome data are interrogated using correlation network analysis that identified significant functional modules pointing toward immune‐related coinciding processes through a common mechanism of remodeling and homeostasis. Novel clues regarding blast resistance include nucleus‐associated redox homeostasis and glycolytic enzyme–mediated chromatin organization which manipulates cell division and immunity. Taken together, the study herein provides evidence that the coordination of nuclear function and reprogramming of host translational machinery regulate resistance mechanism against blast disease. 相似文献
84.
Shngainlang Khongsti Frederick A. Lamare Neizekhotuo Brian Shunyu Sahana Ghosh Arindam Maitra Srimoyee Ghosh 《Genomics》2018,110(2):112-123
Oral Squamous Cell Carcinoma (OSCC) is a serious and one of the most common and highly aggressive malignancies. Epigenetic factors such as DNA methylation have been known to be implicated in a number of cancer etiologies. The main objective of this study was to investigate physiognomies of Promoter DNA methylation patterns associated with oral cancer epigenome with special reference to the ethnic population of Meghalaya, North East India. The present study identifies 27,205 CpG sites and 3811 regions that are differentially methylated in oral cancer when compared to matched normal. 45 genes were found to be differentially methylated within the promoter region, of which 38 were hypermethylated and 7 hypomethylated. 14 of the hypermethylated genes were found to be similar to that of the TCGA-HNSCC study some of which are TSGs and few novel genes which may serve as candidate methylation biomarkers for OSCC in this poorly characterized ethnic group. 相似文献
85.
Guo S Cichy SB He X Yang Q Ragland M Ghosh AK Johnson PF Unterman TG 《The Journal of biological chemistry》2001,276(11):8516-8523
86.
Yoshikazu Izumi Pijush Kanti Nath Hiroshi Yamamoto Hideaki Yamada 《Applied microbiology and biotechnology》1989,30(4):337-342
Summary A convenient and efficient method of NADPH production from NADP+ has been established using a glucose dehydrogenase system involving whole cells and immobilized cells of Gluconobacter suboxydans IFO 3172. Using airdried cells of the bacterium, the optimum conditions for NADPH production were examined, including the cell and glucose concentrations, NADP+ concentration, pH, buffer and reaction temperature. Under suitable conditions, the conversion ratio and the amount of NADPH accumulated reached about 100% and 73 mg/ml of the reaction mixture, respectively, after 1-h reaction. Intact cells of the bacterium also showed high NADPH production even in the reaction mixture without a surfactant. The addition of Triton X-100 to the reaction mixture and freeze-thawing treatment of intact cells enhanced the production. The NADPH production method was further improved by using cells of the bacterium immobilized by entrapment in a -carrageenan gel lattice. The immobilized cells had almost the same enzymatic properties as the air-dried cells. The conditions for the continuous production of NADPH with an immobilized cell column were also investigated. NADPH was produced in a good yield (about 95%) with this continuous process. 相似文献
87.
Involvement of phosphatidylinositol 3-kinase-mediated up-regulation of I kappa B alpha in anti-inflammatory effect of gemfibrozil in microglia 总被引:1,自引:0,他引:1
Jana M Jana A Liu X Ghosh S Pahan K 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(6):4142-4152
The present study underlines the importance of PI3K in mediating the anti-inflammatory effect of gemfibrozil, a prescribed lipid-lowering drug for humans, in mouse microglia. Gemfibrozil inhibited LPS-induced expression of inducible NO synthase (iNOS) and proinflammatory cytokines in mouse BV-2 microglial cells and primary microglia. By overexpressing wild-type and dominant-negative constructs of peroxisome proliferator-activated receptor-alpha (PPAR-alpha) in microglial cells and isolating primary microglia from PPAR-alpha-/- mice, we have demonstrated that gemfibrozil inhibits the activation of microglia independent of PPAR-alpha. Interestingly, gemfibrozil induced the activation of p85alpha-associated PI3K (p110beta but not p110alpha) and inhibition of that PI3K by either chemical inhibitors or dominant-negative mutants abrogated the inhibitory effect of gemfibrozil. Conversely, overexpression of the constitutively active mutant of p110 enhanced the inhibitory effect of gemfibrozil on LPS-induced expression of proinflammatory molecules. Similarly, gemfibrozil also inhibited fibrillar amyloid beta (Abeta)-, prion peptide (PrP)-, dsRNA (poly IC)-, HIV-1 Tat-, and 1-methyl-4-phenylpyridinium (MPP+)-, but not IFN-gamma-, induced microglial expression of iNOS. Inhibition of PI3K also abolished the inhibitory effect of gemfibrozil on Abeta-, PrP-, poly IC-, Tat-, and MPP+-induced microglial expression of iNOS. Involvement of NF-kappaB activation in LPS-, Abeta-, PrP-, poly IC-, Tat-, and MPP+-, but not IFN-gamma-, induced microglial expression of iNOS and stimulation of IkappaBalpha expression and inhibition of NF-kappaB activation by gemfibrozil via the PI3K pathway suggests that gemfibrozil inhibits the activation of NF-kappaB and the expression of proinflammatory molecules in microglia via PI3K-mediated up-regulation of IkappaBalpha. 相似文献
88.
Ray SS Tejero J Wang ZQ Dutta T Bhattacharjee A Regulski M Tully T Ghosh S Stuehr DJ 《Biochemistry》2007,46(42):11857-11864
Although nitric oxide (NO) is important for cell signaling and nonspecific immunity in the fruit fly Drosophila melanogaster, little is known about its single NO synthase (dNOS). We expressed the oxygenase domain of dNOS (dNOSoxy), characterized its spectroscopic, kinetic, and catalytic properties, and interpreted them in light of a global kinetic model for NO synthesis. Single turnover reactions with ferrous dNOSoxy showed it could convert Arg to N'omega-hydroxy-l-arginine (NOHA), or NOHA to citrulline and NO, when it was given 6R-tetrahydrobiopterin and O2. The dNOSoxy catalyzed Arg hydroxylation and NOHA oxidation at rates that matched or exceeded the rates catalyzed by the three mammalian NOSoxy enzymes. Consecutive heme-dioxy, ferric heme-NO, and ferric heme species were observed in the NOHA reaction of dNOSoxy, indicating that its catalytic mechanism is the same as in the mammalian NOS. However, NO dissociation from dNOSoxy was 4 to 9 times faster than that from the mammalian NOS enzymes. In contrast, the dNOSoxy ferrous heme-NO complex was relatively unreactive toward O2 and in this way was equivalent to the mammalian neuronal NOS. Our data show that dNOSoxy has unique settings for the kinetic parameters that determine its NO synthesis. Computer simulations reveal that these unique settings should enable dNOS to be a more efficient and active NO synthase than the mammalian NOS enzymes, which may allow it to function more broadly in cell signaling and immune functions in the fruit fly. 相似文献
89.
Vanadium toxicity is a challenging problem to the health professionals and a cutting-edge medical problem. Vanadium has been
recognized as industrial hazards that adversely affect human and animal reproductive health. Since testicular function is
exquisitely susceptible to reactive-oxygen species, the present study elucidates the possible involvement of oxidative stress
in vanadium-induced testicular toxicity and the prophylactic effects of vitamin E acetate against such adverse effects of
vanadium. The study also characterizes the effects of vanadium on rat adrenal steroidogenesis and determines the underlying
mechanisms of testicular and adrenal interactions in response to vanadium exposure. Significantly reduced sperm count associated
with decreased serum testosterone and gonadotropins level in the vanadium-injected group of rats compared to control substantially
proves the ongoing damaging effects of vanadium-induced ROS on developing germ cells. This is in turn reflected in the appreciable
increase in testicular lipid peroxidation level and decline in the activities of steroidogenic and antioxidant enzymes. However,
oral administration of vitamin E acetate could protect testes from the toxic effects of vanadium. Vanadium also results in
adrenocortical hyperactivity, as evidenced by the elevated secretion of glucocorticoids, adrenal gland hypertrophy and increased
activity of adrenal Δ53β-HSD. However, reversibility of these alterations in adrenocortical activities was vividly reflected after vitamin E acetate
supplementation. All these studies reveal that oxidative stress is the major mechanism of health deterioration and that vanadium
can act as a stressor metal causing chronic stress effects through excitation of hypothalamo-pituitary-adrenal axis. However
antioxidant support by vitamin E acetate may provide significant protection. 相似文献
90.
Manalee Guha Biswabandhu Bankura Sudakshina Ghosh Arup Kumar Pattanayak Saurabh Ghosh Dilip Kumar Pal Anurag Puri Anup Kumar Kundu Madhusudan Das 《PloS one》2015,10(6)
Kidney stone disease (KSD) is a major clinical problem imposing a large burden for both healthcare and economy globally. In India, the prevalence of kidney stone disease is rapidly increasing. This study aimed to evaluate the association between genetic defects in vitamin D receptor (VDR), calcium sensing receptor (CaSR) and claudin 14 (CLDN14) genes and kidney stone disease in patients from eastern India. We enrolled 200 consecutive kidney stone patients (age 18–60 years) (cases) and their corresponding sex and age matched 200 normal individuals (controls). To identify genetic variants responsible for KSD, we performed sequence analysis of VDR, CaSR and CLDN14 genes. Four non-synonymous (rs1801725, rs1042636, rs1801726 and rs2228570), one synonymous (rs219780) and three intronic single nucleotide polymorphisms (SNPs) (rs731236, rs219777 and rs219778) were identified. Genotype and allele frequency analysis of these SNPs revealed that, rs1801725 (Ala986Ser), rs1042636 (Arg990Gly) of CaSR gene and rs219778, rs219780 (Thr229Thr) of CLDN14 gene were significantly associated with KSD. Serum calcium levels were significantly higher in subjects carrying 986Ser allele and calcium excretion was higher in subjects bearing 990Gly allele. In conclusion, rs1801725, rs1042636, rs219778 and rs219780 SNPs were associated with kidney stone risk in patients from the eastern part of India. 相似文献