all Division of Biological Sciences stories

HSPH, Broad map malaria genetic diversity

70652986 — Mon, 26 Mar 2007 05:46:55 -0400

Researchers have created the first map of genetic diversity of the malaria parasite, providing new insights in the fight against a public health scourge that kills one person every 30 seconds.

In work that focused on the most deadly of the four malaria parasites that infect humans, Plasmodium falciparum, researchers found nearly double the diversity they expected. They also identified genetic regions linked to resistance to two anti-malarial drugs.

The advance, by an international team led by researchers at the Broad Institute of Harvard and the Massachusetts Institute of Technology (MIT), can rapidly translate to improvements on the ground, such as better diagnosis of specific malaria strains and monitoring for the emergence of drug resistance, according to Dyann Wirth, chair of the Harvard School of Public Health's Department of Immunology and Infectious Diseases, co-director of the Broad Institute's Infectious Disease Initiative, and the study's senior author.

"One of the immediate applications is that we should be able to develop a tool to detect the emergence of drug resistance in populations and map its spread," Wirth said.

The early detection of drug resistance is critical in better managing the disease. If doctors understand early on that a patient is infected with a strain resistant to a particular drug, they can use other medications and strategies to fight the disease, rather than a blind trial-and-error approach.

"This is a way for one to get ahead of the curve, instead of waiting for clinical failure," Wirth said.

The research represents a critical intersection of advancing technology and basic science aimed at understanding the human genome - pioneered under the leadership of Eric Lander at the Broad Institute - and their application to modern public health problems.

Fatty foods feed heart attacks, researchers say

70652986 — Mon, 26 Mar 2007 06:26:30 -0400

Hold the french fries, doughnuts, and cookies, and save as many as 228,000 heart attacks and deaths from heart disease. That's the message from a team of researchers at the Harvard School of Public Health and Wageningen University in the Netherlands.

"Given the 1.2 million annual [heart attacks] and deaths from coronary heart disease in the United States, near-elimination of industrially produced trans fats might avert between 72,000 and 228,000 coronary heart events each year," the researchers report. Trans fats are also thought to play a role in unexplained sudden deaths and diabetes.

The major sources of trans fats include deep-fried fast foods, bakery products, packaged snack foods, margarines, and crackers. French fries, breaded fish burgers, breaded chicken nuggets, Danish pastries, pies, doughnuts, and cookies are the big offenders. Hamburgers, steaks, lamb chops, and dairy products contain only small amounts of natural trans fats so they don't make the list of "worsts." "The presence of beneficial factors in dairy and these meats may balance the effects of the smaller amount of trans fats they contain," according to Dariush Mozaffarian, lead author of the report that appears in the April 13, 2006, issue of the New England Journal of Medicine.

Ten to 19 percent of the coronary heart disease in the United States (120,000 to 228,000 heart attacks) could be averted by reducing the intake of trans fats, says Walter Willett, head of the research and Fredrick Stare Professor of Epidemiology and Nutrition at the Harvard School of Public Health.

According to the evidence that Mozaffarian, Willett, and their colleagues gathered from studies in the United States and Europe, the "adverse health effects of trans-fatty acids are far stronger on average than those of food contaminants or pesticide residues, which have in some cases received considerable attention. Furthermore, trans fats have no intrinsic health value above their calories."

The research team suggests that trans fats be reduced or eliminated from foods sold in stores, restaurants, and vending machines. Opposing arguments from food manufacturers and restaurants maintain that this would raise costs and lower taste. Recent experiences in Europe indicate that such concerns are overstated, say the researchers. They mention Denmark as a prime example. In that country, all oils and fats used in locally made or imported foods must contain less than 2 percent of industrially produced trans fats.

Holding their breath for the breathless

70652986 — Mon, 26 Mar 2007 05:40:49 -0400

Two researchers at the Harvard School of Public Health (HSPH) got the idea of studying free divers to get information that would help them help the breathless to breathe better. "We hope that by studying these athletes, we can teach patients how to better cope and recover from episodes of breathlessness," says Andrew Binks.

Divers took a battery of tests to see why their breathing capacity is so different from that of other people. Both they and a comparison group of normals were hooked up to a mechanical ventilator that controlled how often and how deeply they breathed. This device prevented the divers from breathing faster and deeper than nondivers.

Professor honored for ongoing environmental research

70652986 — Mon, 26 Mar 2007 05:29:41 -0400

Harvard Professor Jack Spengler and MIT professor Mario Molina shared the $250,000 Heinz award, which recognized the independent bodies of work by Spengler and Molina, although coincidentally the researchers are collaborating on air quality studies in Mexico City. Spengler, Akira Yamaguchi Professor of Environmental Health and Human Habitation in the Department of Environmental Health at the Harvard School of Public Health, was recognized for his research as well as his advocacy efforts. "Dr. Spengler is a true scientific explorer, having charted, virtually by himself, an undiscovered environmental scourge -- indoor air pollution," said Teresa Heinz, chairman of the Heinz Family Foundation. "He has succeeded in focusing the nation's attention on a new insidious, invisible threat, one that had been silently and adversely affecting the nation's health. The technology that scientists rely on today for critical air pollution measurements would not have been possible without Dr. Spengler's pioneering work." Spengler is currently helping to lead the Healthy Public Housing Initiative, an endeavor to respond to high levels of asthma in low-income communities in Boston. He was co-editor of the Indoor Air Quality Handbook. Earlier in his career, he was a researcher with the groundbreaking Six Cities Studies, which explored the environmental risks associated with sulfur dioxide and particle emissions from coal-burning power plants. The studies found a lethal relationship between particulate matter and cardiovascular mortality.

Harvard researchers complete genomic sequence of deadly malaria parasite

70652986 — Mon, 26 Mar 2007 05:23:30 -0400

Malaria is the world's most serious parasitic tropical disease and kills more people than any communicable disease except for tuberculosis. There is more human malaria in Africa today than at any time in history. P.falciparum, the most lethal form of the disease, accounts for the majority of infections, 200 to 300 million, resulting in 1 to 3 million deaths annually. One quarter of the world's population is at risk for infection. Now researchers are looking for clues to the mysteries that have made malaria impossible to defeat with drugs. Dyann Wirth, director of the Harvard Malaria Initiative and professor of immunology and infectious diseases at the Harvard School of Public Health, is author of two papers focusing on what has been learned from the genetic sequencing of P.Falciparum and how it can possibly be applied to public health. The papers appeared in the Oct. 3, 2002, issue of the journal Nature and the Oct. 4, 2002, issue of the journal Science.

Maternal bone lead levels pose toxic prenatal risk

70652986 — Mon, 26 Mar 2007 05:22:10 -0400

Although much attention has been paid to public health efforts to reduce lead exposure in children between the ages of six months and five years, when environmental lead exposures (such as from leaded paint in old houses) tend to be greatest, less attention has been paid to understanding the transfer of lead from mother to fetus and its resulting health effects. Now, Harvard researchers have concluded that elevated maternal bone lead levels are linked to impaired cognitive development in infants. Given the lengthy amount of time lead can reside in maternal bone and that bone is demineralized into the blood during pregnancy, the findings highlight a potentially significant public health problem, linking the history of a mother's lead exposure to risk for the next generation. The study appeared in the July 2002 issue of the journal Pediatrics. Howard Hu, principal investigator of the study, is associate professor at the Harvard School of Public Health. The study was supported by grants from the March of Dimes, National Institute of Environmental Health and Safety, US and Consejo National de Cienca y Technologia and CONSERVA, Department of Federal District, Mexico.

Direct damage from radiation may be passed to neighboring cells

70652986 — Mon, 26 Mar 2007 05:12:00 -0400

Cells communicate, organize, share resources, and form direct connections with one another. They also are affected by damage to their neighbors. Research led by John Little of the Harvard School of Public Health shows that cells hit by radiation can send signals to neighboring cells that result in DNA damage. These findings challenge the long-held assumption that radiation harms cells only by direct contact, suggesting that radiation's biological effects are more complex than previously thought.

Lowering iron levels does not cut heart attack risk for men

70652986 — Mon, 26 Mar 2007 05:05:53 -0400

Men who give blood reduce the amount of iron in their bodies, but that does not result in a reduction in their risk of coronary heart disease (CHD) and heart attack. Iron levels in the body had once been thought to explain the difference in CHD rates among men and women. "The results of this study throw cold water on the 20-year-old hypothesis that reduced iron levels decrease the risk of coronary heart disease," said Alberto Ascherio, associate professor of nutrition and epidemiology at the Harvard School of Public Health. Previous studies hypothesized that women have lower incidences of coronary heart disease than men because of a loss of iron in the blood through menstruation. Men can cut their iron level stores in half by donating one unit of blood per year and can further lower the level to that of premenopausal women by donating two or three units per year. The contrast between U.S. men who donate blood, and those who do not, provided a test for the hypothesis.

Environmental health researcher studies lead poisoning in India

70652986 — Mon, 26 Mar 2007 05:06:28 -0400

Lead is a naturally occurring toxic element, and exposure poses a serious threat to children whose neurological systems are still developing. Some children suffer from brain damage, poor motor skills coordination, and damaged kidneys. But the disease is easily preventable by limiting exposure to the toxic substance. More than 100 million people in India battle the debilitating effects of lead poisoning, according to a recent study, though the harmful results of exposure are preventable. Howard Hu, associate professor of occupational medicine at the School of Public Health, will measure the lead levels in the discarded baby teeth of 300 elementary school-aged children in India and correlate the levels to the children's performances on standardized tests.

Industrial disasters sparked field of environmental health

70652986 — Mon, 26 Mar 2007 05:10:22 -0400

Two large, unnatural disasters helped to create the impetus for the field of environmental health to grow in scope. But before there was a U.S. Environmental Protection Agency and before the National Institutes of Health (NIH) included environmental health, there was the Kresge Center for Environmental Health at Harvard's School of Public Health. Beginning in 1958, the center brought together medical and physical scientists and engineers to investigate the manmade health problems of the 20th century. From a classic focus on industrial workplaces, the Kresge Center has seen environmental health grow to incorporate every part of our natural and constructed habitats.