Sexual transmission of HIV-1 isolate showing G-->A hypermutation.

Retroviral genomes with a high frequency of G-->A mutations are thought to originate during reverse transcription (RT). Here we present a case report of an AIDS patient infected with a subtype F variant where extensive G-->A hypermutation (G-->A Hypm) sequences were found in the protease gene. This patient was failing HAART at the time the hypermutation was found. These sequences were basically encountered in the proviral compartment on two occasions and were persistently absent in the plasma viral population. The patient's viral genotype showed several mutations related to antiretroviral drug resistance in RT (T69N, M184V, T215F, K219Q) and protease (M36I, G48V, I54V, T63L, V82A) genes. The drug regimen was changed and the viral load dropped 0.9 Logs and CD4 count increased by 200 cells/ml. The hypermutation was not found any more in a 1-year follow up. The patient's wife was infected with a similar virus strain and G-->A Hypm sequences were also detected in the RT gene. This is the first report of sexual transmitted G-->A Hypermutation in HIV-1 and suggest that this phenomenon can be genetically coded by the viral RT molecule.

Reduction of electromyographic noise in the signal-averaged electrocardiogram by spectral decomposition.

This paper proposes a technique to improve the quality of high-resolution electrocardiogram by weighting the coherent average of beats by a function of the energy of the corrupting myoelectric noise, prior to subsequent detection of ventricular late potentials. The results obtained with 20 patients indicate the method requires fewer beats than conventional nonweighted average to achieve the same noise level.