Correlation of the serum concentrations of tumour necrosis factor and nitric oxide with disease severity in chronic Chagas disease (American trypanosomiasis).

Pro-inflammatory cytokines such as tumour necrosis factor (TNF) and nitric oxide (NO) are believed to play an important role in the severity of chronic disease. When evaluated in 71 patients who were seropositive for Trypanosoma cruzi and 50 apparently healthy controls, the mean (S.D.) serum concentrations of both TNF [7.65 (1.32) nu. 4.24 (1.53) ng/ml; P<0.001] and NO [114 (40) nu. 74 (21) microM; P<0.0001] were found to be significantly higher in the patients than in the controls. In addition, patients with chronic, symptomatic disease affecting their hearts--eight with dilated cardiomyopathy [8.82 (1.47) ng TNF/ml; 142 (45) microM NO] and 17 others with electrocardiographic alterations [8.37 (1.26) ng TNF/ml; 134 (53) microM NO]--had significantly higher serum concentrations of these cytokines than 34 patients who were in the asymptomatic, indeterminate phase of the disease [6.38 (1.35) ng TNF/ml; 99 (28) microM NO]. In those infected with T. cruzi, it therefore appears that serum concentrations of TNF and NO correlate with disease severity, indicating that these cytokines play some role in the pathogenesis of chronic Chagas disease.

Risk factors related to the occurrence of silent myocardial ischemia in Mexicans.

BACKGROUND: Silent myocardial ischemia is a growing world health problem. It has been related to factors that promote an increase in myocardial oxygen demand or affect coronary vasomotor tone. Coronary artery disease has shown an increasing trend in Mexico in this century. HYPOTHESIS: The aim of the study was to estimate the strength of the association between some risk factors and the occurrence of silent myocardial ischemia. METHODS: A cross-sectional study was conducted and 249 individuals were screened by 24-h Holter electrocardiogram. Silent myocardial ischemia was diagnosed in patients with painless transient ST-segment depression. All subjects were interviewed for coronary risk factors and total serum cholesterol was measured. RESULTS: Silent ischemia was diagnosed in 115 patients (46%), who were older (59 +/- 9 vs. 57 +/- 11 years; p = 0.01). In a logistic regression analysis, a lower risk for silent ischemia was found in patients with thrombolysis [odds ratio (OR) 0.28; 95% confidence interval (CI 95%) 0.14-0.53], or those who followed their medical treatment (OR 0.16; CI 95% 0.04-0.68). The major risk factors were hypercholesterolemia (OR 1.6; CI 95% 0.9-2.9) and more severe coronary artery disease (OR 2.5; CI 95% 1.1-5.7). CONCLUSIONS: Some coronary risk factors are related to silent ischemia. It is still important to diagnose this entity, but modification of its related risk factors should be kept in mind to diminish its occurrence and its severe consequences.

[Comparative study between bisoprolol and metoprolol, combined with hydrochlorothiazide, as antihypertensive therapy]. / Estudio comparativo entre bisoprolol y metoprolol, asociados a hidroclorotiazida, como terapia antihipertensiva.

The main objective of this research was to compare the efficacy and security of bisoprolol (B), a new cardioselective beta-blocker, that does not have intrinsic sympathomimetic activity, and metoprolol associated to hydrochlorothiazide (HCTZ), in the treatment of patients with mild to moderate hypertension. Sixty-two hypertensive patients (47 females and 15 males) aged 20 to 70 years (mean 52.5 +/- 10.4) were included in a double-blind, placebo controlled and randomized clinical trial. After a two-weeks wash out period and a similar placebo phase, patients were randomly assigned to receive either a once-daily dosing of B (10 mg) with 6.25 mg of HCTZ, or M (100 mg) plus 6.25 mg of HCTZ during four-weeks. If there was no reduction below 90 mmHg at the end of this period, the dosing of either beta-blocker was doubled. After eight weeks of treatment, the mean decreases in systolic/diastolic blood pressures from baseline were 31.8/21.2 and 28.0/20.6 mmHg for B/HCTZ and M/HCTZ, respectively (p < 0.0001). There were no clinically significant changes from baseline in laboratory parameters in either group. Reduction in blood pressure with B/HCTZ is associated with adverse events and metabolic changes similar to those observed with other antihypertensive drugs.