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61.
Ihsan R Devi TR Yadav DS Mishra AK Sharma J Zomawia E Verma Y Phukan R Mahanta J Kataki AC Kapur S Saxena S 《DNA and cell biology》2011,30(3):163-171
The association of TP53 codon 72 polymorphism with cancer susceptibility remains uncertain and varies with ethnicity. Northeast India represents a geographically, culturally, and ethnically isolated population. The area reports high rate of tobacco usage in a variety of ways of consumption, compared with the rest of Indian population. A total of 411 cancer patients (161 lung, 134 gastric, and 116 oral) and 282 normal controls from the ethnic population were analyzed for p53 codon 72 polymorphism by polymerase chain reaction-restriction fragment length polymorphism. No significant difference in genotypic distribution of p53 between cases and controls was observed. Results suggested betel quid chewing as a major risk factor for all the three cancers (odds ratio [OR]=3.54, confidence interval [CI]=2.01-6.25, p<0.001; OR=1.74, CI=1.04-2.92, p=0.03; and OR=1.85, CI=1.02-3.33, p=0.04 for lung, gastric, and oral cancers, respectively). Tobacco smoking was associated with risk of lung and oral cancers (OR=1.88, CI=1.11-3.19, p=0.01 and OR=1.68, CI=1.00-2.81, p=0.04). Interactions between p53 genotypes and risk factors were analyzed to look for gene-environment interactions. Interaction of smoking and p53 genotype was significant only for oral cancer. Interactions of betel quid with p53 genotypes in lung cancer showed significant increase for all the three genotypes, indicating a major role of betel quid (OR=5.90, CI=1.67-20.81, p=0.006; OR=5.44, CI=1.67-17.75, p=0.005; and OR=5.84, CI=1.70-19.97, p=0.005 for Arg/Arg, Arg/Pro, and Pro/Pro, respectively). In conclusion, high incidence of these cancers in northeast India might be an outcome of risk habits; further, tissue- and carcinogen-specific risk modification by p53 gene is probable. 相似文献
62.
Hong Q Bakshi RK Palucki BL Park MK Ye Z He S Pollard PG Sebhat IK Liu J Guo L Cashen DE Martin WJ Weinberg DH MacNeil T Tang R Tamvakopoulos C Peng Q Miller RR Stearns RA Chen HY Chen AS Strack AM Fong TM MacIntyre DE Wyvratt MJ Nargund RP 《Bioorganic & medicinal chemistry letters》2011,21(8):2330-2334
We report the discovery of piperazine urea based compound 1, a potent, selective, orally bioavailable melanocortin subtype-4 receptor partial agonist. Compound 1 shows anti-obesity efficacy without potentiating erectile activity in the rodent models. 相似文献
63.
Genetic validation and spectroscopic detailing of DHN-melanin extracted from an environmental fungus
Accurate characterization of melanin using analytical methodologies has proved to be difficult due to its heterogeneity, insolubility in wide pH and broad range of solvents. The present study was undertaken to characterize melanin extracted from an environmental Aspergillus fumigatus AFGRD105 by studying its genes, chemical properties and spectral data. A gene based approach to confirm the type of melanin carried out indicated the extracted melanin to be of the dihydroxynaphthalene type. On comparison with synthetic melanin, UV–Vis and IR spectra of the extracted melanin revealed characteristic peaks that can be further used for confirmation of DHN-melanin extracted from any source. Solid state 13C NMR spectroscopy established the presence of the hydroxyl-naphthalene moiety and validated the results obtained by genetic analysis. The correct assignment of the observed spectral frequency characteristic of functional groups can be further adapted in future works that deal with binding capacities and biomolecule systems involving melanin. 相似文献
64.
Xiong X Xu Q Huang Y Singh RD Anderson R Leof E Hu J Ling K 《Molecular biology of the cell》2012,23(1):87-98
E-Cadherin-mediated formation of adherens junctions (AJs) is essential for the morphogenesis of epithelial cells. However, the mechanisms underlying E-cadherin clustering and AJ maturation are not fully understood. Here we report that type Iγ phosphatidylinositol-4-phosphate 5-kinase (PIPKIγ) associates with the exocyst via a direct interaction with Exo70, the exocyst subunit that guides the polarized targeting of exocyst to the plasma membrane. By means of this interaction, PIPKIγ mediates the association between E-cadherin and Exo70 and determines the targeting of Exo70 to AJs. Further investigation revealed that Exo70 is necessary for clustering of E-cadherin on the plasma membrane and extension of nascent E-cadherin adhesions, which are critical for the maturation of cohesive AJs. In addition, we observed phosphatidylinositol-4,5-bisphosphate (PI4,5P(2)) accumulation at E-cadherin clusters during the assembly of E-cadherin adhesions. PIPKIγ-generated PI4,5P(2) is required for recruiting Exo70 to newly formed E-cadherin junctions and facilitates the assembly and maturation of AJs. These results support a model in which PIPKIγ and PIPKIγ-generated PI4,5P(2) pools at nascent E-cadherin contacts cue Exo70 targeting and orient the tethering of exocyst-associated E-cadherin. This could be an important mechanism that regulates E-cadherin clustering and AJ maturation, which is essential for the establishment of solid, polarized epithelial structures. 相似文献
65.
The multiple sex chromosome system, X1X2Y /X1X1X2X2, in the small Indian mongoose, Herpestes auropunctatus, results from a translocation of a part of Y chromosome to an autosome. It is not possible to distinguish the autosome which harbours the Y chromosome element in the somatic complement. By employing the surface-spreading technique to prophase I meiocytes we have identified the region to which the Y chromosome has been translocated as the short arm of chromosome 9 which is a subtelocentric chromosome. This Y chromosome component lacks heterochromatin and no sex vesicle is organised during meiotic prophase. This suggests to us that Y heterochromatin in mammals may be required for the production of a sex vesicle.We take great pleasure in dedicating this paper to our revered teacher Prof. S.P. Ray-Chaudhuri, who initiated us to the field of Cytogenetics, on the occasion of his 75th birth day 相似文献
66.
R S Sharma S Mokkapati M Rajalakshmi M M Kapur 《Indian journal of experimental biology》1992,30(11):1079-1083
Attempts were made to validate RIA for prolactin (PRL), LH and FSH in semen from normospermic, oligospermic and azoospermic subjects. The RIA used to measure PRL and LH in semen fulfilled the criteria of reliability, whereas low levels of FSH in semen precluded the validation of FSH assay in semen. Semen levels of PRL and LH were significantly (P < 0.05) higher than serum levels in all groups of subjects investigated. Semen levels of FSH in azoospermic men after vasoepididymostomy (VEA), were significantly (P < 0.05) higher compared to azoospermic men prior to surgery. Serum levels of PRL were significantly higher (P < 0.05) in normospermic men compared to oligospermic and azoospermic men prior to and after surgery. Semen levels of PRL in normospermic men were comparable with oligospermic and azoospermic subjects prior to and after surgery. Serum levels of LH in oligospermic and azoospermic men who did not undergo surgery and in men reporting oligospermia after VEA were comparable to normospermic subjects but in men showing azoospermia post surgically, serum LH levels were significantly (P < 0.005) elevated. Semen levels of LH in men reporting azoospermia before surgery and in subjects showing oligospermia or azoospermia post surgically were significantly lower (P < 0.05) compared to men with normal sperm count. Serum levels of FSH were significantly elevated (P < 0.05) compared to semen levels in oligospermic men prior to surgery but this increase was not seen in post VEA subjects. These results were discussed. 相似文献
67.
68.
Present study was carried out to investigate the possible neuroprotective effect of pioglitazone, an antidiabetic agent, peroxisome proliferator-activated receptor gamma (PPARgamma) agonist on acute phase changes in mice model of cerebral ischemia induced by Bilateral Common Carotid artery Occlusion (BCCAO). BCCAO model was used to induce partial global cerebral ischemia. BCCAO induced significant brain infarct size and edema in saline treated control group along with high increase in oxidative stress showed by increase lipid peroxidation and decreased levels of antioxidants like superoxide superoxide dismutage, catalase, glutathione peroxidase. Pioglitazone (20 mg/kg, orally) administration showed neuroprotective effects by reducing cerebral infarct size significantly as compared to control group. Postischemic seizure susceptibility was also reduced as number of positive responders decreased to a significant number. Brain edema was subsided to a significant level. Pioglitazone reduced the plasma TNF-alpha levels as compared to ischemia group significantly. Pioglitazone treatment also improved all the antioxidants levels showing activity against oxidative stress induced by BCCAO. Pioglitazone showed neuroprotection against ischemic insult suggesting the role of PPARgamma agonist in neuroprotective agents. 相似文献
69.
Amit Kapur Gregory Keoleian Alissa Kendall Stephen E. Kesler 《Journal of Industrial Ecology》2008,12(4):539-556
A dynamic substance‐flow model is developed to characterize the stocks and flows of cement utilized during the 20th century in the United States, using the generic cement life cycle as a systems boundary. The motivation for estimating historical inventories of cement stocks and flows is to provide accurate estimates of contemporary cement in‐use stocks in U.S. infrastructure and future discards to relevant stakeholders in U.S. infrastructure, such as the federal and state highway administrators, departments of transportation, public and private utilities, and the construction and cement industries. Such information will assist in planning future rehabilitation projects and better life cycle management of infrastructure systems. In the present policy environment of climate negotiations, estimates of in‐use cement infrastructure can provide insights about to what extent built environment can act as a carbon sink over its lifetime. The rate of addition of new stock, its composition, and the repair of existing stock are key determinants of infrastructure sustainability. Based upon a probability of failure approach, a dynamic stock and flow model was developed utilizing three statistical lifetime distributions—Weibull, gamma, and lognormal—for each cement end‐use. The model‐derived estimate of the “in‐use” cement stocks in the United States is in the range of 4.2 to 4.4 billion metric tons (gigatonnes, Gt). This indicates that 82% to 87% of cement utilized during the last century is still in use. On a per capita basis, this is equivalent to 14.3 to 15.0 tonnes of in‐use cement stock per person. The in‐use cement stock per capita has doubled over the last 50 years, although the rate of growth has slowed. 相似文献
70.