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921.
AIMS: The plasma levels of either brain natriuretic peptide (BNP) or the N-terminal fragment of the prohormone (NT-proBNP) have recently gained extreme importance as markers of myocardial dysfunction. Patients with type 2 diabetes are at high risk of developing cardiovascular complications. This study was aimed to assess whether plasma NT-proBNP levels are at similar levels in type 2 diabetics with or without overt cardiovascular diseases. METHODS: We assayed plasma NT-proBNP in 54 type 2 diabetics, 27 of whom had no overt macro- and/or microvascular complications, while the remaining ones had either or both. The same assay was carried out in 38 healthy control subjects age and sex matched as a group with the diabetics. RESULTS: Plasma NT-proBNP was higher in diabetics (median 121 pg/ml, interquartile range 50-240 pg/ml, ) than in those without complications (37 pg/ml, 21-54 pg/ml, P<0.01). Compared with the controls (55 pg/ml, 40-79 pg/ml), only diabetics with vascular complications had significantly increased plasma NT-proBNP levels (P<0.001). In the diabetics, coronary heart disease and nephropathy (defined according to urinary excretion of albumin) were each independently associated with elevated values of plasma NT-proBNP. CONCLUSIONS: In type 2 diabetes mellitus, patients with macro- and/or micro-vascular complications exhibit an elevation of plasma NT-proBNP levels compared to corresponding patients with no evidence of vascular disease. The excessive secretion of this peptide is independently associated with coronary artery disease and overt nephropathy. The measurement of circulating NT-proBNP concentration may therefore be useful to screen for the presence of macro- and/or microvascular disease.  相似文献   
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BACKGROUND: Worsening of heart failure in patients with myocardial infarction is seldom studied, elderly patients often are not included, and multivariate analysis is uncommon. AIMS: The prospective PRIMA study (Prise en charge de l'Infarctus du Myocarde Aigu; management of acute myocardial infarction) sought to determine the incidence of heart failure worsening, its risk factors, and its prognostic importance in patients with myocardial infarction, regardless of age and hospital facilities, in the "real world" in a region in France, using multivariate analysis. METHODS: Data were prospectively collected in all patients with myocardial infarction admitted in all hospitals in three departments in the Rh?ne-Alpes region in France between September 1, 1993 and January 31, 1995. RESULTS: Among 2,507 patients, 33% were in Killip classes II-IV at admission. Four hundred and sixteen patients (17%) had worsening of Killip class during the first five days. In-hospital mortality (overall: 14%) increased dramatically with Killip class at admission (9% in class I; 62% in class IV) and with worsening of Killip class during the first five days (36% vs 8% if no worsening). In multivariate analysis, older age, diabetes mellitus and anterior Q-wave myocardial infarction were significant predictors of Killip class at admission and of its worsening. The significant predictors of in-hospital mortality were older age, Killip class III at admission and worsening of Killip class during the first five days. CONCLUSION: This large, unselected cohort revealed that among patients with myocardial infarction, heart failure and its worsening are frequent, especially in the elderly, and dramatically worsen the in-hospital mortality.  相似文献   
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The major prostaglandins (PGs) locally produced in adipose tissue both in rodent and man are PGE2 and prostacyclin (PGI2). We have recently described PGI2 as an autocrine promoter and/or amplifier of terminal differentiation of cultured preadipocytes in several species. The effectiveness and specificity of PGI2 as an adipogenic agent are related to its ability to induce in preadipocytes intracellular increases of both cAMP and free calcium. Moreover, PGs of the E series are well known to exert an antilipolytic effect in mature adipocytes. These observations have prompted us to address two questions of physiological interest: 1) Is PGI2 still able to increase cAMP in differentiated adipocytes, behaving thus as a lipolytic agent, and 2) Is PGE2 able to negatively modulate cAMP production in adipose precursor cells, behaving thus as a counteracting effector of PGI2 action? Our results, with respect to cAMP production and/or lipolysis and antilipolysis, demonstrate clearly that in adipose tissue of both rat and man, PGI2 exclusively affects adipose precursor cells whereas PGE2 exclusively affects adipocytes. We propose a model of concerted action for both PGs in the development of adipose tissue mass, PGI2 behaving as an adipogenic-hyperplastic effector and PGE2 as an antilipolytic-hypertrophic effector.  相似文献   
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Aims/Hypothesis The objective of this study was to examine the relationships among insulin and insulin sensitivity and risk factors for cardiovascular diseases in native Ghanaians with and without hypertension.Methods We measured the anthropometric parameters, systolic and diastolic blood pressure, fasting serum triglycerides, cholesterol and high-density lipoprotein cholesterol and fasting and stimulated glucose, insulin and C-peptide of 200 Ghanaian subjects, who were between 25 to 74 years of age, and residing in the Accra Metropolitan area. Serum glucose, C-peptide and insulin concentrations were measured at baseline (fasting) and also 2 h after 75 gm oral glucose drink. Homeostasis model assessment was used to measure insulin resistance. Hypertension was defined as a blood pressure higher than 140/90 mmHg.Results There were 53 subjects with hypertension (HBP) and 147 subjects with normal blood pressure (NBP). The mean BMI, waist circumference and waist-to-hip circumference ratio for HBP and NBP subjects were 27.4±0.8, 24.8±0.4 kg/m2; 89.8±11.7, 81.1±0.9 cm; and 0.87±0.08, 0.82±0.08 respectively, (p<0.05). The fasting and 2-h plasma glucose concentrations in HBP and NBP subjects were 5.5±0.2, 7.2±0.3 mmol/l and 5.2±01, 6.8±0.2 mmol/l respectively (p>0.05). The corresponding fasting and 2-h insulin concentrations were 10.0±0.7, 8.0±0.4 uU/ml and 47.3±3.7, 37.3±2.5 uU/ml respectively (p<0.05). The insulin resistance index (HOMA-IR) in the HBP and the NBP groups were 2.49±0.2 and 1.95±0.13 (p<0.05). The two groups had similar fasting and stimulated C-peptide, lipids and HDL concentrations. Correlations were found between blood pressure and the concentrations of lipids, HDL, fasting and stimulated insulin and C-peptide, and between fasting insulin and HOMA-IR with lipids and HDL concentrations. On multiple regression analysis, fasting insulin and HOMA-IR did not influence blood pressure variations significantly.Conclusions/interpretation We found clustering of hyperinsulinaemia, insulin resistance and truncal obesity in hypertensive Ghanaian subjects but dissociation between insulin resistance, hypertension and atherogenic lipid and lipoprotein profile.Abbreviations HBP hypertension - NBP normal blood pressure - HOMA % BC HOMA derived Beta-cell function - CVD cardiovascular disease - HOMA homeostasis model assessment - HOMA-IR homeostasis model assessment derived insulin resistance  相似文献   
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