Cortisol and estradiol: nongenetic factors for hyperhomocyst(e)inemia.

A low plasma homocyst(e)ine concentration in premenopausal and pregnant women compared with postmenopausal women and men suggests that steroid hormones are nongenetic factors affecting homocysteine metabolism. This hypothesis was tested by determining plasma homocyst(e)ine levels in adult male rats treated with cortisol, estradiol, or a combination of both. Mean plasma homocyst(e)ine concentrations were 3.71 +/- 0.71, 5.26 +/- 1.76, and 4.28 +/- 0.84 nmol/mL in cortisol-treated, estradiol-treated, and cortisol plus estradiol-treated groups, respectively. These values were substantially low compared with the level of 7.32 +/- 0.89 nmol/mL plasma homocyst(e)ine in the control group, indicating a significant effect of steroid hormones on homocysteine metabolism.

Thermolabile defect of methylenetetrahydrofolate reductase in coronary artery disease.

BACKGROUND: To determine whether or not a moderate genetic defect of homocysteine metabolism is associated with the development of coronary artery disease, we studied the prevalence of thermolabile methylenetetrahydrofolate reductase, which is probably the most common genetic defect of homocysteine metabolism. METHODS AND RESULTS: Three hundred thirty-nine subjects who underwent coronary angiography were classified into three groups: (1) patients with severe coronary artery stenosis (> or = 70% occlusion in one or more coronary arteries or > or = 50% occlusion in the left main coronary artery), (2) patients with mild to moderate coronary artery stenosis (< 70% occlusion in one or more coronary arteries or < 50% occlusion in the left main coronary artery), and (3) patients with non-coronary heart disease or noncardiac chest pain (nonstenotic coronary arteries). The thermolability of methylenetetrahydrofolate reductase was prospectively determined in all subjects. Plasma homocyst(e)ine levels were then measured in those with thermolabile methylenetetrahydrofolate reductase. The traditional risk factors for coronary artery disease were thereafter ascertained by chart review of all subjects. The prevalence of thermolabile methylenetetrahydrofolate reductase was 18.1% in group 1, 13.4% in group 2, and 7.9% in group 3. There was a significant difference between the prevalence of thermolabile methylenetetrahydrofolate reductase in groups 1 and 3 (P < .04). All individuals with thermolabile methylenetetrahydrofolate reductase irrespective of their clinical grouping had higher plasma homocyst(e)ine levels than normal (group 1, 14.86 +/- 5.85; group 2, 15.36 +/- 5.70; group 3, 13.39 +/- 3.80; normal, 8.50 +/- 2.8 nmol/mL). Nonetheless, there was no statistically significant difference in the plasma homocyst(e)ine concentrations of these patients with or without coronary artery stenosis. Using discriminant function analysis, thermolabile methylenetetrahydrofolate reductase was predictive of angiographically proven coronary artery stenosis. The traditional risk factors--age, sex, diabetes, smoking, hypercholesterolemia, and hypertension--were not significantly associated with the presence of thermolabile methylenetetrahydrofolate reductase. CONCLUSIONS: Thermolabile methylenetetrahydrofolate reductase is a risk factor for coronary artery disease and is unrelated to other risk factors.

MRI in intraventricular neurocysticercosis: a case report.

A young Mexican female developed neurocysticercosis presenting as a lymphocytic meningoencephalitis with eosinophilia. Parasitic cysts in the fourth ventricle and pre-pontine cistern were well visualized by magnetic resonance imaging but not by computerized tomography. The meningoencephalitis recurred despite treatment with praziquantel and dexamethasone, and obstructive hydrocephalus eventually developed. The patient remains well one year after excision of the intraventricular cyst. This case emphasizes the distinct advantages of magnetic resonance imaging in the diagnosis of intraventricular neurocysticercosis, and the potential need for surgical rather than medical intervention in this condition.