Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
Semen Boosts HIV's Ability to Infect Cells: Study
Semen increases HIV's ability to infect cells, which may explain why it's so difficult to develop genital creams or gels to protect against the AIDS-causing virus, a new study says.
"We think this may be one of the factors explaining why so many drugs that efficiently blocked HIV infection in laboratory experiments did not work in a real world setting," Nadia Roan of the University of California, San Francisco and the Gladstone Institutes, told NBC News.
The researchers tested different microbicides on HIV and found that including semen in the mix made it 10 times easier for HIV to infect cells, and made the microbicides 20 times less effective.
Attaching to certain proteins in semen -- the fluid that carries sperm -- makes it easier for HIV to infect cells, according to the study in the journal Science Translational Medicine.
The researchers found that this problem does not occur with an HIV drug called maraviroc, which may point the way forward in efforts to create new microbicides, NBC News reported.