Hyaluronate levels and markers of oxidative stress in the serum of Sudanese subjects at risk of infection with Schistosoma mansoni.

We showed previously that infection by Schistosoma mansoni not only triggers the production of reactive oxygen species in mouse liver but also leads to the alteration of antioxidant defences. To determine whether such events occur in humans, we measured the serum markers of oxidative stress, i.e., lipid peroxides and protein carbonyl, as well as hyaluronate levels in subjects in the Managil area of the Sudan. Grades of fibrosis were determined by ultrasonographic examination. Two groups were used as controls, one Sudanese and the other European. We found that Sudanese subjects in the endemic area differed from the control groups, both Sudanese and European, insofar as they had higher levels of the serum metabolites measured. The latter increased with the grade of fibrosis. Moreover, protein carbonyl and hyaluronic acid levels correlated positively with lipid peroxide levels. These findings indicate that oxidative stress might contribute to S. mansoni-associated pathology in man. The serum markers considered in our study, obtained by relatively simple techniques, may provide a useful biochemical index for the identification of almost asymptomatic patients who, however, are at risk of developing severe schistosomiasis.

Utility of various clinical, noninvasive, and invasive procedures for determining the causes of recurrence of myocardial ischemia or infarction > or = 1 year after percutaneous transluminal coronary angioplasty.

In patients with recurrent symptoms > or = 1 year after successful percutaneous transluminal coronary angioplasty (PTCA), the decision of whether to proceed directly with coronary angiography or to evaluate the patient noninvasively can be difficult. To determine which demographic, historical, clinical, and laboratory factors are useful in helping to make this decision, 76 consecutive patients who presented > 1 year (768 +/- 309 days) after successful PTCA with resolution of symptoms were studied. The initial PTCA successfully treated all stenoses (except chronically occluded vessels) in all major vessels and segments. The patient group was predominantly men (68%), with a mean age of 64 +/- 10 years. A prior myocardial infarction was present in 39 patients (51%), and there was a mean of 2.8 risk factors per patient. In patients who presented with recurrent symptoms, the Canadian Cardiovascular Society functional class was 2.0 +/- 0.9; 2 patients presented with acute infarctions, 57 were admitted to the hospital with unstable angina, and 17 had stable angina. New electrocardiographic changes at rest were found in 19 of 74 patients (26%) with recurrent angina. A thallium stress test was performed in 40 patients (53%), with a sensitivity of 77% and a specificity of 36% for the presence of a significant stenosis. No nonangiographic variable was predictive of angiographic findings. At angiography, the number of coronary arteries with > or = 50% diameter narrowing was 1.4 +/- 1.0. Forty-two patients had stenosis at a new site, 7 had restenosis, and 27 had no new stenoses.(ABSTRACT TRUNCATED AT 250 WORDS)