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Genetic factors that contribute to the risk of breast cancer are largely not known and association studies have revealed several genes with low penetrance risk alleles for breast cancer. Analysis of these genes may provide important information on the risk factors affecting carcinogenesis. Variations in the ARLTS1, RAD51 and MDM2 genes have been associated with increased risk of different cancer types but for breast cancer the results are not consistent. In this study we investigated the role of the allelic variants in candidate genes acting in the tumor suppressor, DNA repair and p53 pathways as risk factors for familial breast cancer in 147 patients displaying characteristics of familial disease. Presence of the polymorphic variants were investigated by amplification of the corresponding regions and restriction fragment length polymorphism analysis. Genotype and allele frequencies in the patients were significantly different for all three variants. Our results indicate that the polymorphic variants might affect individual susceptibility towards breast cancer.  相似文献   
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We identified nine individuals from three unrelated Turkish families with a unique autosomal recessive syndrome characterized by type I microtia, microdontia, and profound congenital deafness associated with a complete absence of inner ear structures (Michel aplasia). We later demonstrated three different homozygous mutations (p.S156P, p.R104X, and p.V206SfsX117) in the fibroblast growth factor 3 (FGF3) gene in affected members of these families, cosegregating with the autosomal recessive transmission as a completely penetrant phenotype. These findings demonstrate the involvement of FGF3 mutations in a human malformation syndrome for the first time and contribute to our understanding of the role this gene plays in embryonic development. Of particular interest is that the development of the inner ear is completely disturbed at a very early stage--or the otic vesicle is not induced at all--in all of the affected individuals who carried two mutant FGF3 alleles.  相似文献   
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Hydrobiologia - Many populations of Caspian Sea trout (Salmo caspius)—a nationally endangered species in Iran—have been extirpated or depleted due to anthropogenic impacts. The Lar...  相似文献   
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Erdosteine is a mucolytic agent having antioxidant properties through its active metabolites in acute injuries induced by pharmacological drugs. This study was designed to investigate the renoprotective potential of Erdosteine against gentamicin (GM)-induced renal dysfunction by using Technetium-99 m dimercaptosuccinic acid (Tc-99 m DMSA) uptake and scintigraphy in rats. For this purpose, male Wistar rats were randomly allotted into one of the four experimental groups: Control, Erdosteine, GM, and GM + Erdosteine groups. GM and GM + Erdosteine groups received 100 mg/kg GM intramuscularly for 6 days. In addition, Erdosteine and GM + Erdosteine groups received 50 mg/kg Erdosteine orally for 6 days. Renal function tests were assessed by serum blood urea nitrogen (BUN), creatinine levels, as well as scintigraphic and tissue radioactivity measurements with Tc-99 m DMSA. Renal oxidative damage was determined by renal malondialdehyde (MDA) levels, by antioxidant enzyme activities; superoxide dismutase (SOD) and catalase (CAT) and activities of oxidant enzymes; xanthine oxidase (XO) and myeloperoxidase (MPO). GM administration resulted in marked renal lipid peroxidation, increased XO and MPO activities and decreased antioxidant enzyme activities. GM + Erdosteine group significantly had lower MDA levels, higher SOD and CAT activities and lower XO and MPO activities, when compared to GM. Also GM + Erdosteine had lower levels of serum BUN, creatinine and higher renal tissue Tc-99 m DMSA uptake and radioactivity with respect to GM. In conclusion, our results supported a protective role of Erdosteine in nephrotoxicity associated with GM treatment.  相似文献   
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The fusion of viruses with cells and liposomes is reviewed with focus on the analysis of the final extents and kinetics of fusion.Influenza virus andSendai virus exhibit 100% of fusion capacity with cells at pH 5 and pH 7.5, respectively. On the other hand, there may be in certain cases, a limit on the number of virions that can fuse with a single cell, that is significantly below the limit on binding. It still remains to be resolved whether this limit reflects a limited number of possible fusion sites, or a saturation limit on the amount of viral glycoproteins that can be incorporated in the cellular membrane, like the case of virus fusion with pure phospholipid vesicles, in which the fusion products were shown to consist of a single virus and several liposomes. Both viruses demonstrate incomplete fusion activity towards liposomes of a variety of compositions. In the case ofSendai virus, fusion inactive virions bind essentially irreversibly to liposomes. Yet, preliminary results revealed that such bound, unfused virions can be released by sucrose gradient centrifugation. The separated unfused virions subsequently fuse when incubated with a “fresh” batch of liposomes. We conclude, therefore, that the fraction of initially bound unfused virions does not consist of dective particles, but rather of particles bound to liposomes via “inactive” sites. Details of the low pH inactivation of fusion capacity ofinfluenza virus towards cells and liposomes are presented. This inactivation is caused by protonation and exposure of the hydrophobic segment of HA2, and affects primarily the fusion rate constants. Some degree of inactivation also occurs when virions are bound to cellular membranes.  相似文献   
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Molecular Biology Reports - Traumatic brain injury (TBI) is the leading cause of mortality and morbidity in young adults and children in the industrialized countries; however, there are presently...  相似文献   
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The biologist's involvement in value issues concerning the methodology of biological sciences, in establishing the biological basis of ethics and in creating a value system based on biological knowledge is examined. It is proposed that the roots of this involvement are in the conflict of the knowledge-ethic with the established system of values and in the need for metaphysical explanation.This essay is dedicated to the memory of I. Michael Lerner, formerly Professor of Genetics University of California, Berkeley.  相似文献   
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