Dog Health

WASHINGTON (AP) -- The AIDS virus has hideouts deep in the immune system that today's drugs can't reach. Now scientists finally have discovered how HIV builds one of those fortresses - and they're exploring whether a drug already used to fight a parasite in developing countries just might hold a key to break in.

Researchers have long struggled unsuccessfully to attack what they call reservoirs of dormant HIV, and the new work is in very early stages.

But University of Rochester scientists say it may be fairly straightforward to attack one of these reservoirs, blood cells called macrophages that HIV hijacks and turns into viral hideaways.

The new discovery shows the exact steps that HIV takes to do that - and found that some existing drugs, including a long-used treatment for leishmaniasis called miltefosine, can block the main step and thus cause these cells to self-destruct.

"It's a very smart virus," said lead researcher Dr. Baek Kim. "They have to have a very good fence to protect their house for a long time. ... Get rid of the fence, and now their house is gone."

Today's drugs have turned HIV from a quick death sentence into, for many, a chronic infection. Yet those drugs don't eliminate HIV because they can't reach the two known pools of cells where the virus can lie dormant, ever ready to resurface.

So-called memory T cells form one such pool. As the name implies, these are the cells that ensure if you get, say, measles as a child, you're forever immune. They live for years, even decades, making them a logical HIV hideout, and one that scientists have repeatedly sought to dismantle to no avail.

Macrophages, another type of immune cell, form the second pool. They roam the body looking for invaders like bacteria to gobble up. If they get harmed, such as becoming infected by a virus, they're supposed to commit suicide. But HIV instead keeps them alive long past their normal lifespan.

"Up to now, nobody has really thought about how to eliminate the macrophage reservoir," said Dr. Kuan-Teh Jeang, an HIV specialist at the National Institutes of Health. "The imagination now has turned toward, 'How do we eliminate reservoirs?' ... The best way to address our problem is to simply kill those cells."

The Rochester team found that HIV produces a protein that turns on a particular cell-survival pathway. After a multistep process, it ultimately activates an enzyme called Akt that in turn prevents cell suicide, the researchers reported Thursday online in the journal Retrovirology.

That was good news, Kim said, because the Akt pathway is a culprit in certain cancers - meaning oncologists have been trying to target it for some time. So Kim put human HIV-infected macrophages in lab dishes and started adding drugs known to block the Akt pathway, to see if any killed the cells.

He had luck: Miltefosine and a cousin named perifosine both rapidly killed the macrophages, thus depriving HIV of this hideout.

Perifosine is currently being studied as a possible cancer drug. But miltefosine is known to be safe through its use in leishmaniasis patients. So Kim's goal is to rapidly study the already available miltefosine in animals, to see if it truly targets infected macrophages well enough to then test in HIV patients.

"The evidence they show is in fact pretty good," said NIH's Jeang, who says the next step should be a test of miltefosine in monkeys infected with SIV, the monkey version of the AIDS virus.

© 2008 The Associated Press.

NEW YORK (AP) -- Doctors can cut the risk of cerebral palsy in half for very premature babies by giving their mothers magnesium sulfate just before they give birth, new research shows.

The mineral compound, also known as Epsom salts, is already used to treat preganancy-related high blood pressure and to stop early labor. Doctors should consider giving it to women about to deliver an extremely preterm infant, said one of the researchers, Dr. John Thorp of the University of North Carolina.

"It's cheap. It's readily available. It doesn't harm anybody. I think it will be widely adopted," said Thorp.

The research was led by Dr. Dwight Rouse at the University of Alabama at Birmingham and was presented Thursday at a meeting of the Society for Maternal-Fetal Medicine in Dallas.

Cerebral palsy is a serious complication of premature birth. It's caused by damage to the part of the brain that controls movement and results in poor muscle control and coordination.

Thorp said it isn't clear how magnesium sulfate works, but it is thought to open up blood vessels in the newborn's brain.

In the government-funded study, researchers gave an infusion of magnesium sulfate to women about to give birth to a premature baby to see if it would reduce the risk of cerebral palsy. Enrolled in the study were 2,241 women who were 24 to 31 weeks pregnant. Infants born before 37 weeks are considered premature.

Most of the women were in early labor because their water broke. They were given either the compound or a fake solution. The infants were examined for signs of cerebral palsy at birth and over the next two years.

Of the babies who survived, moderate or severe cerebral palsy occurred in about 2 percent of those in the treatment group compared to about 4 percent of those whose mothers didn't get the compound.

The number of infants who died was about the same in both groups.

"Cerebral palsy is not a terribly common outcome in preterm infants but when it does happen, it's devastating," said Dr. Judy Aschner, chief of neonatology at Vanderbilt Children's Hospital, who was not involved in the study.

She said doctors will want to see the details on side effects when the study is published before making any changes in the care of mothers in preterm labor. Magnesium sulfate acts like a sedative and can make moms and infants groggy and sleepy, she said.

"This is a really important study and potentially one that could change general practice," Aschner said.

In another study presented at the conference, researchers found that women who take folic acid for at least a year before they become pregnant may reduce their chances of early premature birth by 50 to 70 percent. Taking folic acid is already recommended for women of childbearing age to prevent birth defects to the brain and spinal cord, such as spina bifada.

"Here we have an added reason to motivate women to take it and to take it early in their lives," said Dr. Alan Fleischman, medical director of the March of Dimes. The group was giving the research an award at the Dallas meeting.

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On the Net:

March of Dimes: http://www.marchofdimes.com

© 2008 The Associated Press.

In the second time in a month, the pop star has been physically removed from her home by police. Los Angeles Police officers physically removed pop star Britney Spears from her home early today, placing the troubled celebrity on a "mental health evaluation hold," authorites said.

NEW YORK - For die-hard fans of the New York Giants and New England Patriots, Sunday's Super Bowl may not be just a game. It may be a health hazard.

For rabid fans of the New York Giants and New England Patriots, this Sunday's Super Bowl won't be just a game - it could be a health hazard