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991.
Endothelin has been identified as a potent vasoconstrictor. The aim of this study was to evaluate urinary endothelins and their relation to other markers of renal damage, such as microalbuminuria, creatinine, and N-acetyl-beta-glucosaminidase (NAG), in a group of recently diagnosed (less than 1 year) hypertensive subjects and a control group. We selected 50 subjects and divided them into two groups: 27 hypertensive patients (15 females and 12 males) without previous pharmacologic therapy, and 23 healthy, normotensive subjects (12 females and 11 males). All patients underwent a history and physical examination, chest x-ray, electrocardiography, funduscopy, and hematologic and biochemical analyses. Endothelins, microalbuminuria, creatinine, and NAG values were also determined in 24-hour urine samples. Creatinine, microalbuminuria, and NAG values were found to be higher in hypertensive than in normotensive subjects. The hypertensive group showed a nonsignificant elevation of total endothelin. In conclusion, the determination of elevated urinary endothelin does not appear to be an early marker of organ damage in hypertensive subjects. The urinary excretion of protein, creatinine, and NAG was higher in hypertensive subjects. A positive correlation was found between the urinary excretion of endothelins and markers of renal damage, microalbuminuria and NAG values. The relationship between endothelins and hypertension was without statistical significance.  相似文献   
992.
OBJECTIVES: We assessed the influence of alcohol intake on the development of symptomatic heart failure (HF) in patients with left ventricular (LV) dysfunction after a myocardial infarction (MI). BACKGROUND: In contrast to protection from coronary heart disease, alcohol consumption has been linked to cardiodepressant effects and has been considered contraindicated in patients with HF. METHODS: The Survival And Ventricular Enlargement (SAVE) trial randomized 2231 patients with a LV ejection fraction (EF) <40% following MI to an angiotensin-converting enzyme inhibitor or placebo. Patients were classified as nondrinkers, light-to-moderate drinkers (1 to 10 drinks/week), or heavy drinkers (>10 drinks/week) based on alcohol consumption reported at baseline. The primary outcome was hospitalization for HF or need for an open-label angiotensin-converting enzyme inhibitor. Analyses were repeated using alcohol consumption reported three months after MI. RESULTS: Nondrinkers were older and had more comorbidities than light-to-moderate and heavy drinkers. In univariate analyses, baseline light-to-moderate alcohol intake was associated with a lower incidence of HF compared with nondrinkers (hazard ratio [HR] 0.71; 95% confidence interval [CI] 0.57 to 0.87), whereas heavy drinking was not (HR 0.91; 95% CI 0.67 to 1.23). After adjustment for baseline differences, light-to-moderate baseline alcohol consumption no longer significantly influenced the development of HF (light-to-moderate drinkers HR 0.93; 95% CI 0.75 to 1.17; heavy drinkers HR 1.25; 95% CI 0.91 to 1.72). Alcohol consumption reported three months after the MI similarly did not modify the risk of adverse outcome. CONCLUSIONS: In patients with LV dysfunction after an MI, light-to-moderate alcohol intake either at baseline or following MI did not alter the risk for the development of HF requiring hospitalization or an open-label angiotensin-converting enzyme inhibitor.  相似文献   
993.
BACKGROUND: Atrial fibrillation (AF) is associated with extracellular matrix remodeling involving atrial fibrosis and atrial dilatation. Angiotensin II mediated pathways and matrix metalloproteinases (MMPs) have been implicated in these processes. Our aim was to study atrial structural remodeling and the expression of the angiotensin receptor subtypes and MMPs and their inhibitors (TIMPs) in patients with mitral valve disease with and without AF. METHODS AND RESULTS: Biopsies from right and left atrial appendages (RA and LA) were taken from patients undergoing CABG (n=9, all in sinus rhythm (SR)) or mitral valve surgery (MVS; n=19; 9 with permanent AF and 10 in SR). Patients with MVS and AF had significantly larger atria (versus MVS and SR: p=0.02; versus CABG: p<0.01). The MVS patients had significantly more fibrosis than the control CABG group. Fibrosis was increased in both the AF and SR MVS groups in the LA, but only in the MVS-AF group in the RA. These AF patients had significantly more tricuspid regurgitation than SR patients. MMP-1 was down-regulated in LA of MVS patients (p=0.02) independent of the underlying rhythm (SR or AF; p=0.95). In RA biopsies, MMP-1 was down-regulated only in the MVS and AF group. MMP-9 was down-regulated in the MVS patients compared to CABG both in the RA and LA, and without a difference between the SR and AF groups. Protein expression of AT-1, AT-2, MMP-2, TIMP-1, -2 and -4, TNF-alpha, and TNF-alpha-converting enzyme did not differ significantly between the 3 groups. CONCLUSIONS: Concordant changes between MMP-expression and fibrosis during mitral valve disease, both in LA and RA, suggest involvement of MMPs in structural atrial remodeling. AF itself did not contribute to altered fibrosis or MMP-expression in the LA. The association between AF and RA changes may be precipitated by greater hemodynamic load due to tricuspid regurgitation in these patients.  相似文献   
994.
BACKGROUND: Echocardiography and B-type natriuretic peptide (BNP) are diagnostic tests for congestive heart failure (CHF), but an emergency diagnosis can be difficult. OBJECTIVE: To assess the diagnostic performance of BNP testing and echocardiographic assessment of left ventricular systolic function, separately and combined, for the identification of CHF in patients with acute dyspnea. DESIGN: Prospective, multinational, multicenter study. SETTING: Patients presenting to emergency departments in seven hospitals between June 1999 and December 2000. PATIENTS: A total of 1,586 patients with acute dyspnea. MAIN OUTCOME MEASURES: Echocardiographic determination of ejection fraction (EF) and point-of care BNP measurement for the diagnosis of CHF. RESULTS: Seven hundred nine of the 1,586 patients underwent echocardiography; 492 patients (69.4%) had a final diagnosis of CHF. Patients with CHF were older (68.5 years vs 61.6 years, p < 0.0001), had a lower EF (39.5% vs 56.1%, p < 0.0001), and a higher BNP (683 pg/mL vs 129 pg/mL, p < 0.0001) than patients without CHF. Area under the receiver operating characteristic (ROC) curve for the diagnosis of CHF was significantly higher for BNP (0.89) than for EF (0.78; area under the ROC curve difference, 0.12; p < 0.0001). The sensitivity of BNP > or = 100 pg/mL for the diagnosis of CHF was 89%, and specificity was 73%. Values for EF < or = 50% had a sensitivity of 70% and a specificity of 77%. Multivariate logistic regression analysis showed that, in combination with clinical, ECG, and chest radiograph data, BNP > or = 100 pg/mL and EF < or = 50% remained independent predictors of CHF (odds ratios, 32.1 and 6.2, respectively). The proportions of patients who were correctly classified were 67% for BNP alone, 55% for EF alone, 82% for the two variables together, and 97.3% when clinical, ECG, and chest radiograph data were added. CONCLUSION: BNP measurement was superior to two-dimensional echocardiographic determination of EF in identifying CHF, regardless of the threshold value. The two methods combined have marked additive diagnostic value.  相似文献   
995.
996.
In human African trypanosomiasis (HAT), two disease stages are defined: the first, or haemo‐lymphatic stage, and the second, or meningo‐encephalitic stage. Stage determination forms the basis of therapeutic decision and is of prime importance, as the drug used to cure second‐stage patients has considerable side‐effects. However, the tests currently used for stage determination have low sensitivity or specificity. Two new tests for stage determination in the cerebrospinal fluid (CSF) were evaluated on 73 patients diagnosed with HAT in Côte d'Ivoire. The polymerase chain reaction (PCR) detecting trypanosome DNA (PCR/CSF) is an indirect test for trypanosome detection whereas the latex agglutination test detecting immunoglobulin M (LATEX/IgM) is an indicator for neuro‐inflammation. Both tests were compared with classically used tests, double centrifugation and white blood cell count of the CSF. PCR/CSF appeared to be the most sensitive test (96%), and may be of use to improve stage determination. However, its value for therapeutic decision appears limited, as patients whose CSF was positive with PCR were successfully treated with pentamidine. This result confirms those of previous works that showed that some patients with trypanosomes in the CSF could be treated successfully with pentamidine. LATEX/IgM, which depending on the cut‐off, showed lower sensitivity of 76% and 88%, but higher specificity of 83% and 71% for LATEX/IgM 16 and LATEX/IgM 8 respectively, appears more appropriate for therapeutic decision making.  相似文献   
997.
998.
A prospective series of 65 patients with surgically confirmed lung cystic hydatid disease was evaluated in terms of their radiologic characteristics, serologic response, and presence of cysts in other organs. Cysts were mostly single and located in lower lung lobes. Liver compromise was found in 34% of the patients. Despite a systematic search, no patient showed brain cysts in this series. Twelve patients had previous hydatid disease: six in the liver and eight in the lung (two had involvement of both organs in the past). Serology using bovine cyst fluid in an immunoblot assay was 85% sensitive. Serologic response was not associated with number or cyst or compromise of other organs but was clearly associated to the presence of at least one complicated cyst. Cyst status in terms of complications should be described to allow appropriate assessment of serologic evaluations.  相似文献   
999.
A 1-day meeting, attended by invited respiratory and primary-care specialists all of whom had an international profile and a specific interest in Chronic Obstructive Pulmonary Disease (COPD), considered specific research recommendations from the Global Initiative in Obstructive Lung Disease (GOLD) workshop report. Attendees discussed developing a tool to complement spirometry and help primary-care physicians assess treatment success in patients with chronic obstructive pulmonary disease. Discussion focused on the requirement of such a tool, and the limitations of existing tools. Proposals followed for a simple, cost-effective checklist for primary-care. This paper is a consensus report of the discussions from the meeting. Decisions reached on the proposed questionnaire were unanimous.  相似文献   
1000.
gammadelta T cells undergo massive expansion in the peripheral blood of renal transplant recipients who are infected with cytomegalovirus (CMV). In a 3-year prospective study, the relationship between the evolution of CMV infection and the kinetics of gammadelta T cell amplification was followed for 10 months after transplantation. Patients with late gammadelta T cell expansion (>/=45 days) had significantly longer (P<.0001) and higher (P<.0003) pp65 antigenemia and more-symptomatic CMV disease than did patients with early expansion. Analysis of data for each patient showed that gammadelta T cell expansion is concomitant with the resolution of CMV infection and disease, regardless of the CMV serologic status of donor and recipient before transplantation. These observations point to gammadelta T cell percentage determination as a new, rapid, and reliable prognosis factor to predict the resolution of CMV infection and strongly suggest that gammadelta T cells play a protective role against CMV infection.  相似文献   
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