Protein-nucleic acid interactions and DNA conformation in a complex of human immunodeficiency virus type 1 reverse transcriptase with a double-stranded DNA template-primer

Myocardial glucose metabolism has been shown to be heterogeneous in patients with hypertrophic cardiomyopathy (HCM). We tested the hypothesis that myocardial glucose metabolism differs between patients with HCM and those with hypertensive heart disease (HHD) associated with asymmetrical septal hypertrophy. We studied 12 patients with HCM, 7 HHD patients associated with asymmetrical septal hypertrophy using 18F 2-deoxyglucose (FDG) and positron emission tomography. We calculated % FDG fractional uptake in the inter-ventricular septum and posterolateral wall. Heterogeneity of FDG uptake was evaluated by % interregional coefficient of variation of FDG fractional uptake in each wall segment. In both the interventricular septum and posterolateral wall, % FDG fractional uptake was not significantly different between the two groups. The % interregional coefficient of variation for both interventricular septum (10.6 +/- 1.6 vs. 4.1 +/- 0.5, p < 0.01) and posterolateral wall (5.9 +/- 0.7 vs. 3.8 +/- 0.5, p < 0.05) was significantly larger in patients with HCM than in HHD patients associated with asymmetrical septal hypertrophy. Echocardiography demonstrated that the degree of asymmetrical septal hypertrophy was similar between the two groups. These results suggest that myocardial glucose metabolism may be more heterogeneous in patients with HCM compared to HHD patients associated with asymmetrical septal hypertrophy, although the left ventricular shape is similar. The difference in the heterogeneity might have resulted from differences in the pathogeneses of the two diseases.     

Human immunodeficiency virus reverse transcriptase codon 215 mutations diminish virologic response to didanosine-zidovudine therapy in subjects with non-syncytium-inducing phenotype

Eight zidovudine-experienced subjects received zidovudine and didanosine for 30 weeks followed by 30 weeks of didanosine monotherapy. At study entry, plasma from 4 subjects had human immunodeficiency virus RNA pol T215Y/F mutant and 4 had codon 215 wild type. All 8 subjects had non-syncytium-inducing virus phenotype. Sustained 10-fold decreases in plasma RNA levels were seen only in subjects who initially had 215 wild type RNA, despite the development of a T215Y/F mutation during combination therapy. Virologic and immunologic benefits were maintained in this group with didanosine monotherapy. No subject developed a pol L74V codon mutation. Significant differences in plasma virus load and CD4 cell responses were seen in this zidovudine-didanosine combination pilot study relative to codon 215 genotype.