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61.
Roma people are underprivileged, neglected population worldwide, with severe healthcare problems. They have significantly increased prevalence of cardiovascular morbidity, presumably related to their poor social status, alcohol consumption and smoking habits. Assuming that genetic background also plays a role in their susceptibility for cardiovascular diseases, we hypothesized that APOA5 gene polymorphisms, an important role-player in lipid metabolism and in the development of metabolic syndrome and cardio/cerebrovascular events, may also be involved. We examined four APOA5 polymorphisms in 363 Roma and 404 Hungarian DNA samples. For rs662799, rs2266788, rs207560 and rs3135506 we found elevated plasma triglyceride levels in the risk allele carriers compared to non-carriers in both populations. At least a two-fold significant increase was detected in minor allele frequencies in Roma when compared to Hungarians, except the rs2266788 variant. Haplotype analysis revealed significant increase of APOA5*2, APOA5*4 in Roma, as opposed to the higher levels of APOA5*5 found in Hungarians. Different linkage disequilibrium was found between rs207560 and rs3135506 variants in Roma compared to Hungarians. The profound differences observed in almost all APOA5 polymorphisms in Roma require special attention, since these variants are known to associate with cardio/cerebrovascular susceptibility.  相似文献   
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Diffuse large B-cell lymphoma (DLBCL) is the most frequent, complex and heterogeneous lymphoma of adulthood. Heterogeneity is expressed at clinical, genetic, and molecular levels. It is known that BCL-6 expression is a favorable prognostic factor in DLBCL. However, the underlying mechanisms of BCL-6 expression in DLBCL relapse are not yet elucidated. Here, we present so far undescribed clinical phenomenon of switching BCL-6+ protein expression into BCL-6 expression in 19 of 41 relapsed DLBCL patients. The switch in relapsed DLBCL was associated with more aggressive clinical course of the disease. Bone marrow infiltration and high IPI risk were more often present in BCL-6 patients. Significantly increased biochemical parameters, such as LDH, beta-2 macroglobulin, CRP, and ferritin have been found, as well as significantly decreased serum Fe, TIBC, and hemoglobin. A Ki-67 proliferation marker was considerably high in relapsed DLBCL, but without significant differences between BCL-6+ and BCL-6 groups of patients. Thus, switching of the positive into negative BCL-6 expression during DLBCL relapse could be used as a prognostic factor and a valuable criterion for treatment decision.  相似文献   
64.
Sequence analysis was conducted on structural and non-structural genes of 7 strains of dengue virus type-3 (DENV-3 virus) isolated in Indonesia and Thailand in the year 1973, 1994, and 1998 from patients with different clinical manifestations. In general, sequence similarity among isolates was greater than 93%, indicating that the mutation rate of DENV-3 circulating in this region was not more than 7% in the last 3 decades and suggesting that sequences that may responsible for viral architectures and/or biological function were strictly conserved. Mutations unique to viral strains associated with specific clinical manifestations were not found. Alignment of PrM/M and E nucleic acid sequences followed by parsimony analysis of sequences obtained in this study and published elsewhere allowed generation of phylogenetic trees, demonstrating that DENV-3 strains isolated in Indonesia in 1998 belonged to a separate cluster (subtype 2) from those isolated between 1973-1985 (subtype 1).  相似文献   
65.
BACKGROUND AND AIM: Determination of the local densities of Helicobacter pylori and its genotypic variations in gastric biopsy specimens by using novel real-time PCR-based methods could support the precise diagnosis and understanding of H. pylori infections. METHODS: Serial dilutions of H. pylori (0.016-16 microg/microl), control, bacterial, and human DNA samples were prepared. Fresh-frozen gastric biopsy specimens were taken from 103 patients, and the DNA was isolated. Quantitative determination of the ureaseA gene using hybridization probes with parallel evaluation of an internal human control gene (beta-globin) was performed by real-time PCR. CagA and VacA s1 genotypic characterizations were also performed. The data were compared with urea breath test (UBT), histology, and serological testing. RESULTS: The presence of H. pylori could be detected by ureaseA-fluorescence energy transfer (53%), UBT (51%), serological testing (48%), and histology (52%) when compared with the gold standard (54%). A significant correlation was found between the quantitative real-time ureaseA/beta-globin ratio-based H. pylori frequency and the UBT results (P<0.01). Significantly increased bacterial density was found in the erosions when compared with the healthy part of the antrum and corpus (P<0.01). Real-time PCR VacA s1 results were in significant correlation (P<0.01) with those of serological tests, but CagA results were not. The genomic profiles (VAC/GAC) were different in 13.7% of the cases, which involved three different locations in the stomach. CONCLUSION: Real-time PCR was the most reliable method for H. pylori diagnosis. Furthermore, quantification and genotyping could also be performed using this technique. The density of H. pylori was significantly increased in macroscopic erosions.  相似文献   
66.
GeroScience - The neuroprotective effects of pituitary adenylate cyclase-activating polypeptide (PACAP) have been shown in numerous in vitro and in vivo models of Parkinson’s disease (PD)...  相似文献   
67.
Hormonal replacement therapy (HRT) in postmenopausal women has been shown to increase both triglyceride (TG) and high-density lipoprotein (HDL) cholesterol levels. To better understand the effects of conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA), the 2 most commonly prescribed hormones in HRT, on the different subpopulations of TG-rich and HDL lipoproteins, we conducted a placebo-controlled, double-blind, randomized, crossover study consisting of 3 different phases in 14 postmenopausal women. The 3 phases, each 8-week long, included: (1) placebo, (2) CEE 0.625 mg/d, and (3) CEE 0.625 mg/d and MPA 2.5 mg/d. Slight and statistically nonsignificant elevations in TG levels were observed during the CEE treatment. While very-low-density lipoprotein (VLDL) cholesterol levels were not significantly affected by CEE and CEE + MPA, both HRT treatments lowered remnant lipoprotein (RLP) cholesterol (-14% and -37%, respectively). Compared with placebo, CEE caused a significant increase in HDL, HDL(2), apolipoprotein (apo) A-I, LpAI, alpha1, and prealpha1 levels (12%, 27%, 17%, 26%, 60%, and 102%, respectively). The combination therapy blunted the CEE effect on all HDL parameters, resulting in HDL, HDL(2), and LpAI levels being no longer significantly different from placebo. Apo A-I levels and alpha1, and prealpha1 levels were still significantly higher than placebo (+11%, +50%, and +112%, respectively). These results indicate that HRT has beneficial effects on RLP levels and that, while the estrogen component of HRT has a beneficial effect on the HDL subpopulations mostly associated with coronary heart disease (CHD) protection, MPA partially inhibits this effect.  相似文献   
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69.
Vascular injury in acute gastric mucosal damage   总被引:2,自引:0,他引:2  
Recent investigations indicate that microvascular injury, leading to increased vascular permeability and capillary stasis, precede the development of chemically induced hemorrhagic mucosal lesions in the stomach. The vascular damage is more amenable to protection by prostaglandins and sulfhydryls than the diffuse surface mucosal cell injury. The vascular and mucosal lesions may be the result of direct toxicity of damaging agents (eg, ethanol, HCl, NaOH) and the release of vasoactive amines and leukotrienes. We review here our recent studies performed in rats indicating that intraarterial infusion of LTC4 or LTD4 in the stomach caused vascular injury as revealed by monastral blue. Infusion of leukotrienes alone caused no hemorrhagic mucosal lesions but aggravated the damage caused by 25, 50, or 100% ethanol and 0.2 N HCl given intragastrically. The ethanol-induced mucosal lesions were slightly diminished by the lipoxygenase inhibitor L-651,392 and markedly decreased by eicosapentaenoic acid, which competes with arachiconic acid as a substrate for 5-lipoxygenase. These results are discussed and correlated with biochemical results from other laboratories demonstrating increased levels of leukotrienes in the gastric mucosa after administration of ethanol and decreased release following pretreatment with prostaglandins or sulfhydryl-related agents. New data thus support a mediatory role for leukotrienes in the pathogenesis of vascular injury and mucosal lesions in the stomach.  相似文献   
70.
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