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51.
The aim of the present investigation was to study the major chromosomal aberrations (CA) like deletion, translocation, inversion and mosaic in prostate cancer patients of Tamilnadu, Southern India. Totally 45 blood samples were collected from various hospitals in Tamilnadu, Southern India. Equal numbers of normal healthy subjects were chosen after signing a consent form. Volunteers provided blood samples (5 ml) to establish leukocyte cultures. Cytogenetic studies were performed by using Giemsaanding technique and finally the results were ensured by spectral karyotyping (SKY) technique. In the present investigation, major CA like deletion, translocation, inversion and mosaic were identifed in experimental subjects. Results showed frequent CA in chromosomes 1, 3, 5, 6, 7, 9, 13, 16, 18 and X. In comparison with experimental subjects, the control subjects exhibited very low levels of major CA (P〈0.05). In the present study, the high frequency of centromeric rearrangements indicates a potential role for mitotic irregularities associated with the centromere in prostate cancer tumorigenesis. Identification of chromosome alterations may be helpful in understanding the molecular basis of the disease in better manner.  相似文献   
52.
Eight weeks of latent iron deficiency in weaned female rats of Sprague Dawley strain maintained on experimental low-iron diet (18–20 mg/kg) did not significantly change the gross body, weight and tissue weights of brain and liver. Packed cell volume (PCV) and hemoglobin concentration remained unaltered. However, non-heme iron content in liver and brain decreased significantly (p<0.001). The activities of glutamate dehydrogenase, glutamic acid decarboxylase, and GABA-transaminase (GABA-T) in brain decreased by 15%, 11.4% and 25.7% respectively. However, this decrease was not statistically significant. Binding of3H Muscimol at pH 7.5 and 1 mg protein/assay increased by 143% (p<0.001) in synaptic vesicular membranes from iron-deficient rats as compared to the controls.3H glutamate binding to the synaptic vesicles was also carried out under similar condition. However, the L-glutamate binding was reduced by 63% in the vesicular membranes of iron deficient animals. These studies indicate that iron plays important functional role in both excitatory and inhibitory neurotransmitter receptors.  相似文献   
53.
The antiulcerogenic effects of the methanolic extract ofSolanum nigrum berries (SBE) on aspirin induced ulceration in rats with respect to antioxidant status in the gastric mucosa have been investigated. Oxygen free radicals are considered to be important factors in the pathogenesis of gastric ulcer. The level of lipid peroxides, which were elevated highly in rats with acute gastric mucosal injury was taken as an index of oxidative stress. The activities of antioxidant defense enzymes were also decreased considerably by oral gastric administration of aspirin. The decreased levels of antioxidant enzymes and increased mucosal injury were altered to near normal status upon pretreatment with (SBE) when compared to the ulcer induced rats. The results indicate that (SBE) may exert its gastroprotective effect by a free radical scavenging action. Our observations suggest that (SBE) may have considerable therapeutic potential in the treatment of gastric diseases.  相似文献   
54.
Eight weeks of latent iron deficiency in weaned female rats of Sprague Dawley strain maintained on experimental low-iron diet (18–20 mg/Kg) did not significantly change the gross body weight and tissue weights of brain and liver. Packed cell volume (PCV) and hemoglobin concentration remained unaltered. However, non-heme iron content in liver and brain decreased significantly (P<0.001). The activities of glutamate dehydrogenase, glutamic acid decarboxylase, and GABA-transaminase (GABA-T) in brain decreased by 15%, 11.4% and 25.7% respectively. However, this decrease was not statistically significant. Binding of3H Muscimol at pH 7.5 and 1 mg protein/assay increased by 143% (P<0.001) in synaptic vesicular membranes from iron-deficient rats as compared to the controls.3H glutamate binding to the synaptic vesicles was also carried out under similar condition. However, the L-glutamate binding was reduced by 63% in the vesicular membranes of iron deficient animals. These studies in dicate that iron plays an important functional role in both excitatory and inhibitory neurotransmitter receptors.  相似文献   
55.
ES materials released along with the release of mf showed immunosuppression as evidenced by a decrease in T lymphocyte levels in the immunised animals. Lipid fractions of the mf associated ES materials and protein fractions of the detergent soluble materials were found to cause suppression of immune response in the host. Further study revealed that the suppression associated with the lipid fractions is actually the end result and that mf associated ES materials is actually a mixture of immunosuppressive and immunopotentiating components and the release of the components is most likely regulated.  相似文献   
56.
microRNAs (miRNAs) are evolutionarily conserved small noncoding RNAs, also known as micromanagers of gene expression. Polymorphisms in the miRNA pathway (miR-polymorphisms) are emerging as powerful tools to study the biology of a disease and have the potential to be used in disease prognosis and diagnosis. Advancements in the miRNA field also indicate a clear involvement of deregulated miRNA gene signatures in cancers, and several polymorphisms in pre-miRNA, miRNA binding sites or targets have been found to be associated with various cancers. The miRNA polymorphisms have also been reported to influence tumor aggressiveness as well as survival of cancer patients. miRNAs have a revolutionary impact on cancer research over recent years. They emerge as important players in tumorigenesis, leading to a paradigm shift in oncology. The extensive and comprehensive use of miRNA microarrays has enabled the identification of a number of miRNAs as potential biomarkers for cancer. Many miRNAs have been identified to act as oncogenes, tumor suppressors, or even modulators of cancer stem cells and metastasis. Some studies not only reported the identified miRNA biomarkers, but also deciphered their target genes and the underlying mechanisms. The rapid discovery of many miRNA targets and their relevant pathways has contributed to the development of miRNA-based therapeutics.  相似文献   
57.
Extensive research has demonstrated the protective properties of antioxidants, which scavenge reactive oxygen species and their precursors, as well as up-regulate enzymes involved in the repair of cellular damage. Several case–control studies have showed higher blood levels of antioxidants and decreased oxidative stress in younger individuals when compared with older ones. Cell damage caused by free radicals appears to be a major contributor in aging and degenerative diseases of aging such as cancer, cardiovascular disease, cataracts, compromised immune system, rheumatoid arthritis and brain dysfunction. The objective of this study was to determine the variation of Circulating levels of selected antioxidants (enzymic and non enzymic) and oxidative stress marker in younger and older humans. The results showed that a majority of the younger age group participants showed a significant increase in enzymic and nonenzymic antioxidant status and a decrease in oxidative stress when compared with the older age group.  相似文献   
58.
Matrix metalloproteinase-9 (gelatinase B) plays a key role in cancer invasion and metastasis by degrading the extracellular matrix and basement membrane barriers. A cytosine (C) > thymidine (T) single nucleotide polymorphism (SNP) at position −1562 in the MMP-9 promoter is reported to influence the expression of the gene. Genotyping of MMP-9 −1562 C→T promoter polymorphism in 140 gastric cancer patients and 132 healthy control subjects was carried out in order to evaluate its association with progression and development of gastric cancer. The SNP was genotyped by tetra-primer amplification refractory mutation system-polymerase chain reaction followed by agarose gel electrophoresis. Statistical methods were adopted to test for the significance of the results. Risk factor profile of the patients revealed age above 50 years, smoking, alcoholism as the factors associated with the disease. The distribution of genotype frequencies in gastric cancer patients were 28.7 % of CC, 45.5 % of CT and 25.7 % of TT, whereas in control subjects 31.8 % of CC, 53.03 % of CT and 15.15 % of TT, respectively. The allelic frequencies were 51.51 % of C and 48.48 % of T in patient group and 58.33 % of C and 41.66 % of T in controls respectively. The present study shows the possible association of epidemiological risk factors with gastric cancer. There is an increased frequency of T allele in the disease compared to control subjects. However, there is no association of the MMP-9 −1562 C→T promoter polymorphism in the development of gastric cancer.  相似文献   
59.
60.
The effect of the oral administration ofVitex negundo leaf extract on the levels of enzymic and non-enzymic antioxidants were studied in the adjuvant induced arthritic (AIA) rats The levels of antioxidant enzymes such as SOD, CAT, GPx, G6PD, GSH and Vit-C were estimated in various groups of the experimental rats. It was observed that the antioxidant enzyme levels in the AIA were significantly low when compared to normal rats. A significant decrease in enzymic antioxidant—SOD, CAT, GPx, G6PD and non-enzymic antioxidant—GSH, Vit-C were observed in the liver of AIA rats compared to the normal rats. These results suggest that the leaf extract ofVitex negundo possesses antioxidant activity.  相似文献   
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