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91.
We have investigated immunohistochemically the effect of dl-alpha-tocopherol (vitamin E) on thyroid gland with 6-n-propyl-2-thiouracil (PTU)-induced hypothyroidism in rats. The animals were divided into four groups. Rats in group I were designated as control, rats in group II were treated with injections of PTU (10 mg/kg) for 15 days, rats in group III were treated with injections of PTU+vitamin E (10 mg/100 g) for 15 days. Rats in group IV were treated with injections PTU for 15 days and kept for 15 next days after cessation of PTU treatment. At the end of experiment, the animals were killed by decapitation, blood samples were obtained, thyroid tissues were collected and processed for quantitative evaluation of immunohistochemical PCNA (marker of cell proliferation), Bax (pro-apoptotic marker) and Bcl-2 (anti-apoptotic marker) staining. There was an increase in the number of PCNA-immunopositive cells in follicular epithelial cells of group II rats compared with other groups (p<0.05). After vitamin E treatment, the number of PCNA-immunopositive cells decreased (p<0.05) while the number of Bax-immunopositive cells increased (p<0.05). The number of Bcl-2-positive follicular epithelial cells of group IV rats was higher than in those of other groups (p<0.05). The results of this study indicate that hypothyroidism induces cell proliferation in the thyroid gland and vitamin E may promote involution of the gland.  相似文献   
92.
The interaction of the platelet glycoprotein (GP) Ib-IX-V complex with von Willebrand factor (VWF) is a critical step in the adhesion of platelets to the subendothelial matrix following endothelial cell damage, particularly under arterial flow conditions. In the human GP Ib-IX-V complex, the recognition of VWF appears to be mediated entirely by GP Ibalpha, the largest of four GP Ib-IX-V polypeptides. The goal of the present study was to investigate the involvement of the cytoplasmic domain of GP Ibalpha in the GP Ib-IX-VWF interaction under both static conditions and in the presence of high fluid shear stress. Using Chinese hamster ovary (CHO) cells that express GP Ibbeta, GP IX, and either wild-type GP Ibalpha or GP Ibalpha mutants missing various lengths of the cytoplasmic domain, we evaluated adhesion and flow-driven cell rolling on immobilized VWF in a parallel-plate flow chamber. Cells expressing GP Ibalpha polypeptides with truncations of 6-82 amino acids rolled faster than cells expressing wild-type GP Ibalpha. Cells that expressed polypeptides with intact actin-binding protein 280 binding sites (truncated to residue 582 of 610) rolled more slowly than those expressing GP Ibalpha with longer truncations. The rolling velocity of cells expressing truncated GP Ibalpha mutants increased with decreasing VWF coating density. In addition, a fraction of the truncated cells exhibited saltatory translocation at the lower VWF densities. Studies measuring the GP Ibalpha-VWF bond strength of three of the mutants using laser tweezers showed that progressive deletion of the cytoplasmic domain led to progressive weakening of the strength of individual GP Ibalpha-VWF bonds.  相似文献   
93.
A series of 3-alkyl-4-phenylethylidenamino- (8) and 3-alkyl-4-(3-phenylallylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (9) was synthesized from the reaction of the corresponding 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (1), with phenylacetaldehyde and cinnamaldehyde. 3-Alkyl-4-(2-phenylethylamino)- (10) and 3-alkyl-4-(3-phenylpropylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (11) were obtained from the selective reduction of compounds (8) and (9) with NaBH4. The in vitro antitumor activity of the novel compounds was screened and the highest inhibition of tree tumor cell lines was observed for the compounds containing phenylethylenamino and phenylethylamino groups at position 4 of 1,2,4-triazol ring.  相似文献   
94.
Summary The aim of this study was to investigate the effects of excess all-trans retinoic acid, a vitamin A metabolite, on pancreatic organogenesis and TGF-β2 expression during prenatal development in rats.First group of animals used as control while a single dose of 60 mg/kg all-trans retinoic acid was ingested by the mothers, at day 8 of gestation (before the neurulation period) in group II and at day 12 of gestation (after the neurulation period) in group III, and all embryos were sacrificed at day 18 of gestation. TGF-β2 expression was detected in the capsule, acini and Langerhans islets in the control group. In the pancreas of group II, dilatation and congestion of interlobular vessels were observed. Langerhans islet structures were completely absent. Moreover acinar TGF-β2 immune reactivity was not determined. In group III, acinar expression of TGF-β2 in acid was similar to that in the controls but their Langerhans islets TGF-β2 immune reactivity was significantly less than the controls.In view of the present findings we suggest that TGF-β2 plays important role in pancreatic morphogenesis and administration of excess all-trans retinoic acid before neurulation inhibit TGF-β2 expression disrupted pancreatic morphogenesis particularly Langerhans islets. However, its administration after neurulation had less adverse affect on pancreatic organogenesis and TGF-β2 immune reactivity.  相似文献   
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97.
The aim of our study was to determine the effect of monocyte chemotactic protein-1 (MCP-1), CC chemokine receptor 2 (CCR2), and CC chemokine receptor 5 (CCR5) gene polymorphisms on the susceptibility and clinicopathological characteristics of prostate cancer. Genotyping was performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method in 156 histopathologically confirmed prostate cancer patients and 152 healthy subjects. Individuals with AA genotype or at least one A allele of CCR2 V64I gene polymorphism had a higher risk for prostate cancer as compared with those with GG genotype (p=0.010 and p=0.028, respectively). CCR5 Δ32/wt genotype and CCR5 Δ32 allele were also found to be involved in the susceptibility to prostate cancer (p=0.028 and p=0.030, respectively). However, there was no significant association between MCP-1-2518 A/G gene polymorphism and prostate cancer risk. Prostate cancer patients carrying AA genotype or at least one A allele of CCR2 V64I had significantly increased risk for high stage disease (p=0.002 and p=0.039, respectively) and metastasis (p=0.004 and p=0.022, respectively). The CCR2 A allele (64I allele) was significantly associated with high T stage (p=0.001) and metastasis (p=0.005) as compared with CCR2 G allele (64V allele). Our data indicate that gene polymorphism of CCR2 V64I may influence the susceptibility and clinicopathological characteristics of prostate cancer and CCR5 Δ32 allele may also be an important risk factor for prostate cancer in Turkish men population.  相似文献   
98.
Elmaci C  Oner Y  Ozis S  Tuncel E 《Biochemical genetics》2007,45(9-10):691-696
The genetic diversity and phylogenetic relationships of 108 individual sheep from three Turkish sheep breeds (K?v?rc?k, Gökçeada, and Sak?z) were studied using RAPD analysis. Polymorphisms within and between populations were assayed using 15 random primers, and 82 loci were amplified ranging from 250 to 2,500 bp. The percentage of polymorphic loci was found to be 80.49, 78.05, and 73.17%, for K?v?rc?k, Gökçeada, and Sak?z sheep breeds, respectively. Total genetic diversity was 0.2265, and the average coefficient of genetic differentiation was 0.1181. Genetically, the Gökçeada breed was more closely related to the Sak?z breed than to the K?v?rc?k breed.  相似文献   
99.
100.
Epidemiological studies suggest various kinds of immune dysregulation in hemodialysis (HD) patients. The aim of this study was to investigate the relationship between immune functions and nutritional status of HD patients. We studied 54 patients with ESRD on chronic HD, included 34 females and 20 males with mean age 46.6 +/- 16.3 (18-77) years. We measured the height and dry weight of all patients. The BMI was calculated by dividing weight (kg) by height squared (m(2)). In all patients serum urea, creatinine, albumin, iron, cholesterol, triglyceride, CRP, IgG, IgM, IgA, CD4, CD8, CD19, CD16-56 lymphocytes were measured. Kt/V values were calculated according to DOQI guideline. In this study, a positive correlation between albumin, cholesterol, and triglyceride levels as nutritional parameters and immune functions in terms of total and subtype lymphocyte counts was observed. Further prospective studies are needed to determine the clinical importance of this finding and the appropriate means of measurement and effects of nutrition on immune function in hemodialysis patients.  相似文献   
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