Infections by Helicobacter pylori are responsible for duodenal and gastric
ulcers and are a significant risk factor for the development of gastric ade
nocarcinoma. H. pylori was discovered in 1983, but many institutes in Canad
a, Europe, and the United Stares are already involved in programs to unders
tand and treat the infections, as reflected by the growing number of intern
et sites devoted to this bacterium. Most AIDS patients and about 20% of chi
ldren with acute lymphoblastic leukemia develop Pneumocystis carinii pneumo
niae. Information on clinical symptoms and treatment, as well as the P. car
inii genome sequencing project, are described at several web sites. Student
s and researchers wishing to understand the correlation between telomere le
ngth and AIDS may turn to web sites of the University of Colorado and Washi
ngton University School of Medicine for the latest on telomeres and telomer
ase, and their function in aging and cancer. (C) 2000 Editions scientifique
s et medicales Elsevier SAS.