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High blood pressure (BP) is a major determinant of cardiovascular events in obesity. The beta2- and beta3-adrenoceptor polymorphisms are associated with obesity and hypertension. In the present study, we examine the relationships of beta2- and beta3-adrenoceptor polymorphisms with further weight gain-induced BP elevation in obese subjects. Changes in BP, body weight, total body fat-mass, waist-to-hip ratio, plasma norepinephrine (NE) and leptin levels, and beta2(Arg16Gly)- and beta3(Trp64Arg)-adrenoceptor polymorphisms were measured periodically over a 5-year period in 55 entry obese (body mass index [BMI]> or =25.0 kg/m(2)) normotensive (BP<140/90 mmHg) men. BP elevation and weight gain were defined as > or =10% increases from entry levels over 5 years in mean BP or BMI. Obese subjects with weight gain, BP elevation or weight gain-induced BP elevation had higher frequencies of the Gly16 allele of Arg16GIy and Arg64 allele of Trp64Arg. Subjects carrying the Gly16 or Arg64 alleles had significantly greater total fat-mass and waist-to-hip ratio at entry and over a 5-year period compared to the subjects who did not carry these polymorphisms. Subjects carrying the Gly16 allele had similar levels of plasma NE, higher levels of plasma leptin and a lower slope of the regression lines between plasma leptin and NE levels. Those carrying the Arg64 allele had higher plasma NE levels at entry and over a 5-year period compared to the subjects without the Arg64 allele, but plasma leptin levels and slopes were similar. The findings demonstrate that the Arg64 allele of the beta3-adrenoceptor polymorphisms relates to weight gain-induced BP elevation accompanying high plasma NE (heightened sympathetic activity) in obese men. The Gly16 allele of the beta2-adrenoceptor polymorphisms links to weight gain-induced BP elevation associated with leptin resistance. beta2- and beta3-adrenoceptor polymorphisms could predict the future BP elevation and further weight gain-induced BP elevation in originally obese subjects.  相似文献   
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Chronological changes in the complement system in sepsis   总被引:6,自引:0,他引:6  
The time courses of serum complement levels and the severity of sepsis were compared in two groups of septic patients, one in which the patients survived (surviving group) and one in which they did not (nonsurviving group). The components of the complement system, namely, C3a, C4a, C5a, CH50, C3, C4, and C5, were measured at several points in time after the diagnosis of sepsis had been established. A 2-antibody radioimmunoassay was used to measure C3a, C4a, and C5a; the latex agglutination test was used to measure C3 and C4; nephelometry was used to measure C5; and Meyer's 50% hemolysis method was used to measure CH50. Following the diagnosis of sepsis, the levels of CH50, C3, and C4 were significantly lower in the nonsurviving than the surviving group, while the levels of C3a and C4a were significantly higher in the nonsurviving than the surviving group. The C5a levels were significantly higher in the nonsurviving than the surviving group, although no significant intergroup differences were subsequently noted. These results suggest that the serum levels of C3a, C4a, C5a, CH50, C3, and C4 could serve as indices of the severity of sepsis. Thus, monitoring the complement system may be useful for predicting the outcome of patients with sepsis.  相似文献   
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We report a rare case of advanced renal cell carcinoma in apatient who showed complete resolution of metastases to thelung and bones after nephrectomy, partial jejunectomy and subsequentalpha-interferon therapy. The patient was a 54-year-old manwhose right lung and left femur metastases were detected beforenephrectomy. In the seventh week after nephrectomy, a partialjejunectomy was carried out because of the obstructive ileuscaused by intraluminal multiple metastases of the jejunum. Apathological fracture of the metastasized right humerus occurredsubsequently. After four months of intramuscular alpha-interferonadministration (3x106 units/day), however, x-rays revealed thecomplete disappearance of the metastatic lung shadow and a solidunion of the humerus, and there were no tumor cells in the femurspecimen resected at the subsequent reconstruction surgery ofthe left leg. Seven years have passed from onset, and the patientis still alive and disease free.  相似文献   
5.
Mechanisms of Cardioprotection by Volatile Anesthetics   总被引:2,自引:0,他引:2  
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6.
We examined a gene polymorphism of a novel Z-disc-related protein, myospryn (cardiomyopathy-associated 5). We focused on one haplotype block associated with a tag single nucleotide polymorphism (SNP) that covered 16 of 27 coding SNPs with linkage disequilibrium (minor allele frequency 0.413). Screening a myospryn polymorphism (K2906N) in a general health check-up of a rural Japanese population revealed an association with cardiac diseases (p=0.0082). In further analysis of the interaction between K2906N and cardiac function in patients, K2906N was associated with the anteroseptal wall thickness of the left ventricle in a recessive model (p=0.0324) and with the ratio of the peak velocity of the early diastolic filling wave to the peak velocity of atrial filling (A/E) (p=0.0278). In an association study based on left ventricular wall thickness, we found a significant difference in the K2906N genotype between controls and patients with cardiac hypertrophy. These results suggest that the K2906N polymorphism could be clinically associated with left ventricular hypertrophy and diastolic dysfunction independent of known parameters. Although the precise mechanism underlying this association remains to be elucidated, treatment with angiotensin II induced an increase in heart myospryn mRNA level in vitro and in vivo. Our results suggest that the polymorphism of myospryn is associated with left ventricular hypertrophy, and an association between a Z-disc protein and cardiac adaptation in response to pressure overload.  相似文献   
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The core sequence of the enhancer of murine leukemia virus (MuLV) long terminal repeat is highly conserved in a large number of MuLV strains and appears to play an essential role when SL3-3 or Moloney strains induce T cell lymphoma in mice. We found by using the electrophoretic mobility shift assay that a polyomavirus enhancer core-binding protein, PEBP2, bound to this core motif of MuLV. We also noted that PEBP2 in several hematopoietic cell lines derived from B lymphocyte, macrophage and myelocyte lineages migrated significantly faster than the authentic PEBP2 detected in NIH3T3 (ibroblasts. Interestingly, PEBP2 detected in the cell lines of T lymphocyte lineage appeared to contain both types, which were indistinguishable in electrophoretic mobility from those of NIH3T3 and of B lymphocyte, macrophage and myelocyte lineages. The treatment of the nuclear extract containing PEBP2 with phosphatase generated PEBP3, which is a subcomponent of PEBP2 and retained the same DNA-binding specificity as PEBP2. The altered mobility of hematopoietic cell-derived or T lymphocyte-derived PEBP2 was found to be due to the alteration of the mobility of PEBP3. Based on the distinct mobility of PEBP2/3 of T lymphocytes from those of other hematopoietic cells, we discuss the implication of PEBP2 in MuLV-induced T cell leukemia and T cell-specific gene expression.  相似文献   
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Recent advances in molecular genetics have revealed the mechanisms underlying a variety of inherited human disorders. Among them, mutations in G protein-coupled receptors have clearly demonstrated two types of abnormalities, namely loss of function and constitutive activation of the receptors. Thromboxane A2 (TXA2) receptor is a member of the family of G protein-coupled receptors and performs an essential role in hemostasis by interacting with TXA2 to induce platelet aggregation. Here we identify a single amino acid substitution (Arg60-->Leu) in the first cytoplasmic loop of the TXA2 receptor in a dominantly inherited bleeding disorder characterized by defective platelet response to TXA2. This mutation was found exclusively in affected members of two unrelated families with the disorder. The mutant receptor expressed in Chinese hamster ovary cells showed decreased agonist-induced second messenger formation despite its normal ligand binding affinities. These results suggest that the Arg60 to Leu mutation is responsible for the disorder. Moreover, dominant inheritance of the disorder suggests the possibility that the mutation produces a dominant negative TXA2 receptor.  相似文献   
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