Health Highlights: June 17, 2007
Alzheimer's Enzyme May Explain Illness-Linked Seizures Embryonic Gene Screens Safe for Babies: Study Vietnam Reports 1st Bird Flu Death Since 2005 FDA Approves Drug for Pulmonary Arterial Hypertension Heart Group Suggests a Lifesaving Father's Day Gift First OTC Weight Loss Drug Goes on Sale in U.S.
Here are some of the latest health and medical news developments, compiled by editors of HealthDay:
Alzheimer's Enzyme May Explain Illness-Linked Seizures
U.S. researchers say an enzyme that helps form the amyloid-beta protein associated with Alzheimer's disease may also be responsible for seizures that often accompany the condition. Drugs that target this enzyme, which is called beta-secretase (BACE), might cut the attacks, say a team at the MassGeneral Institute for Neurodegenerative Disorders, Boston.
Reporting Sunday in the online edition of the journal Nature Cell Biology, the team say that BACE -- one of two enzymes that snip off and create amyloid-beta -- also influence the function of sodium channels on the surface of brain cells. These channels are crucial to the transmission of signals in nerve cells, and sodium channel disruptions are known to be strongly linked to seizures.
In their studies using brain tissue from animal models and Alzheimer's patients, the MassGeneral team found that Alzheimer's-linked BACE does, in fact, help disrupt sodium channel function.
"Our study suggests that the BACE inhibitors currently being developed to educe amyloid-beta generation in Alzheimer's disease patients may also help prevent seizures by alleviating disrupted neural activity," lead researcher Dora Kovacs, director of the institute's Neurobiology of Disease Laboratory in the Genetics and Aging Research Unit, said in a prepared statement.
Embryonic Gene Screens Safe for Babies: Study
Preimplantation genetic diagnosis (PGD) -- in which doctors remove a cell from three-day-old embryos to look for genetic disease -- appears to pose no harm to babies, Belgian researchers report.
The procedure, first introduced in 1990, analyzes fertilized eggs for genetic problems prior to implantation in the mother's womb, as happens in in vitro fertilization (IVF). But experts have worried that the procedure might pose a long-term safety risk to offspring, the BBC reported.
In the study, researchers at Brussels' Free University say that 563 of the 583 babies in the study that underwent PGD were born alive -- a rate that matches that of conventional IVF or another fertility procedure called ICSI, where sperm is injected into the egg.
PGD babies also had comparable birth weights to infants who did not receive the procedure, and the rate of birth defects or malformations was also similar between PGD, IVF and ICSI children at two months and two years of age.
The findings were published at a meeting of the European Society of Human Genetics.
"I'm very reassured and not at all surprised by these latest results," Dr. Alan Handyside, a spokesman for the British Fertility Society and one of scientists who developed PGD in the 1980s, told the BBC. But he said longer-term data was still needed to confirm the procedure's safety.
In a related study, Danish researchers reporting at the same meeting say that noninvasive screening in early pregnancy can cut Down syndrome births by 50 percent. They used a combination of ultrasound examination of the fetal neck ("nuchal translucency") and maternal blood tests to assess the presence of the disorder. The test is usually carried out at between 11 and 14 weeks of gestation.
Beginning in 2004, Denmark's National Board of Health recommended routine use of the combination test. Implementation of the guidelines has reduced the number of Danish children born with Down syndrome, according to a team at the Kennedy Institute in Glostrup.
"When we looked further at the history of children born with Down syndrome, we found that their mothers had declined the offer of screening, or had taken it up too late in pregnancy," lead researcher Dr. Karen Brondum-Nielsen said in a statement.
Vietnam Reports 1st Bird Flu Death Since 2005
The death on June 10 of a 20-year-old man from northern Ha Tay province is the first bird flu fatality recorded in Vietnam since 2005, the country's official media reported Saturday.
The man's family raised fighting cocks as well as ducks, the Vietnam News Agency added. According to the Associated Press, the bird flu death brings the country's total to 43.
The World Health Organization says that 191 people have died from infection with H5N1 avian flu worldwide, usually from close contact with infected birds. The concern is that the virus might mutate to a strain that could be passed easily person-to-person, sparking an epidemic.
H5N1 has made something of a resurgence in Vietnam, with the government reporting outbreaks in poultry in 18 provinces since early May, the AP said. Those outbreaks have resulted in the slaughter of over 200,000 birds, mainly ducks.
FDA Approves Drug for Pulmonary Arterial Hypertension
The U.S. Food and Drug Administration on Friday approved the drug Letairis (ambrisentan) for the treatment of pulmonary arterial hypertension, a rare but life-threatening condition marked by continuous high blood pressure within the arteries of the lungs.
"Letairis represents a valuable addition to the treatment alternatives for this orphan disease," said Dr. John Jenkins, director of FDA's Office of New Drugs. "Letairis is similar to an existing drug, but offers the potential for fewer drug interactions."
In pulmonary arterial hypertension, the small arteries in the lungs become narrowed or blocked, so the heart must work harder to pump blood through them. Eventually, the overworked heart muscle may become weak and lose its ability to pump enough blood through the lungs. Symptoms include shortness of breath, fatigue, chest pain, dizzy spells and fainting.
About 100,000 people in the United States have pulmonary arterial hypertension, the FDA said.
Heart Group Suggests a Lifesaving Father's Day Gift
Looking for a Father's Day gift for Sunday? The Association for Eradication of Heart Attack (AEHA) is suggesting that families give dads a heart attack prevention test. The association is also asking hospitals, clinics and physicians to offer Father's Day specials with discounted rates.
"One of the most meaningful Father's Day gifts would be a heart attack preventive screening test," said Dr. Morteza Naghavi, founder of the AEHA and chairman of its SHAPE (Screening for Heart Attack Prevention and Education) Task Force. "This is an excellent way to show Dad that you love him and want him to enjoy a long and healthy life."
The SHAPE guideline calls for men from 45 to 75 years old and women 55 to 75 years old to undergo screening to assess coronary plaque or carotid wall thickness. It also recommends the coronary calcium scan (Heart Scan) or carotid scan (Carotid IMT) -- two tests that have proven to be strong predictors of those who are vulnerable to a heart attack or stroke.
"The key is identifying asymptomatic patients at risk before a critical event occurs. With current medical therapies, we can reduce the chances of having a heart attack or sudden death by approximately 75 percent," said Dr. Daniel Berman, director of cardiac imaging at Cedars-Sinai Medical Center in Los Angeles. "The imaging tests are far more accurate than blood tests in identifying the patients at risk and in need of medical therapy."
Heart disease is the leading cause of death in the United States. According to the U.S. Centers for Disease Control and Prevention, there will be approximately 700,000 first heart attacks in 2007, and an estimated 159,600 men will lose their lives, many within an hour of the event.
First OTC Weight Loss Drug Goes on Sale in U.S.
The first FDA-approved over-the-counter weight loss pill goes on sale across the United States Friday. The drug, called alli, prevents the absorption of fat in the intestine. It's a lower-dose version of the prescription weight-loss drug Xenical.
While some welcome the arrival of the OTC pill -- which will cost about $1.80 a day -- others have reservations or are openly critical, Newsday reported.
Weight loss specialist Dr. Dennis Gage, of Lenox Hill Hospital in New York City, isn't impressed with alli.
"The reality of weight loss pills is that people rarely lose weight when they take them. And when they do lose weight, it comes back," he told Newsday. Gage noted that Xenical produces only moderate weight loss.
Dr. Irwin Klein, chief of endocrinology and metabolism at North Shore University Hospital in Manhasset, N.Y., noted that alli causes the same side effects as Xenical, including frequent bowel movements.