September 17, 2007, 5:08 AM CT

Gene determines whether male body odor smells pleasant

To a number of, urine smells like urine and vanilla smells like vanilla. But androstenone, a derivative of testosterone that is a potent ingredient in male body odor, can smell like either - depending on your genes. While a number of people perceive a foul odor from androstenone, commonly that of stale urine or strong sweat, others find the scent sweet and pleasant. Still others cannot smell it at all.

New research from Rockefeller University, performed in collaboration with researchers at Duke University in North Carolina, reveals for the first time that this extreme variability in people's perception of androstenone is due in large part to genetic variations in a single odorant receptor called OR7D4. The research is reported September 16 as an advance online publication of the journal Nature.

Androstenone, found in higher concentrations in the urine and sweat of men than of women, is used by some mammals to convey social and sexual information, and the ability to perceive androstenone's scent may have far-reaching behavioral implications for humans.

In the largest study ever conducted of its kind, scientists at Rockefeller University presented nearly 400 participants with 66 odors at two different concentrations and asked them to rate the pleasantness and intensity of each odor. When researchers at Duke University identified OR7D4 as a receptor that androstenone selectively activates, Leslie Vosshall, Chemers Family Associate Professor and head of the Laboratory of Neurogenetics and Behavior at Rockefeller University and Andreas Keller, a postdoc in her lab, formed a collaboration with them, and began collecting blood samples from participants and isolated their DNA. The Duke team, led by Hiroaki Matsunami, used DNA from each participant to sequence the gene that encodes the OR7D4 receptor......... Posted by: Emily      Read more         Source

September 14, 2007, 5:14 AM CT

Prolonged respiratory problems for oil spill clean-up volunteers

Workers and volunteers who helped in the clean-up effort after the 2002 Prestige oil spill off the Galician coast of Spain exhibit prolonged respiratory symptoms resulting from their exposure, say scientists from Spain in the first study to examine the long-term effects of such exposures on workers respiratory health.

The findings were published in the second issue for September of the American Journal of Respiratory and Critical Care Medicine, published by the American Thoracic Society.

In November 2002, the oil taker Prestige sank off the northwestern coast of Spain, spilling about 67,000 tons of oil that contaminated more than 1,000 kilometers of coastline. More than 100,000 workers and volunteers participated in the clean-up effort. During the first few weeks, clean-up work was done mainly by local fishermen and their families. That initial period was characterized by an improvisational approach and a lack of personal protective equipment, as per the study.

Between January 2004 and February 2005, more than two years after the initial disaster, the scientists administered a questionnaire to determine the long-term implications of the clean-up participation on the population of local fishermen who were most directly affected by the disaster. The questionnaire, which could be self-administered or completed through a telephone interview, assessed the fishermens respiratory problems, use of medicine for respiratory problems, and their beliefs and level of anxiety and about the health effects of the spill......... Posted by: Emily      Read more         Source

September 14, 2007, 5:11 AM CT

Dermatologists identify North Texas leishmaniasis outbreak

A team of dermatologists and dermatopathologists at UT Southwestern Medical Center has identified nine North Texas cases of an infectious skin disease common in South America, Mexico and in the Middle East, where it is sometimes referred to as a Baghdad boil.

Numerous cases of the disease, called leishmaniasis, have been reported in troops returning from Iraq and Afghanistan. But for the first time, cases of this dangerous infection are appearing in North Texas in patients who have not traveled to endemic areas.

The infection causes nonhealing sores that can be the size of a half-dollar or larger and that look like boils. These sores commonly last for 6 to 12 months and because they are often mistaken for a staph infection, patients may have been given multiple courses of standard antibiotics without success.

The disease is caused by a single-celled parasite called Leishmania, and special cultures must be done in order to confirm the diagnosis of leishmaniasis.

The identified cases were from Waxahachie, Hillsboro and Glenn Heights, all areas south of Dallas; Tom Bean, Anna, Savoy and Nevada, all north of Dallas; and North Richland Hills.

North Texas doctors must have a high index of suspicion and understand that this organism must now be considered endemic in this area, said Dr. Kent Aftergut, a clinical instructor of dermatology at UT Southwestern and in private practice at Methodist Charlton Medical Center......... Posted by: Emily      Read more         Source

September 12, 2007, 8:34 PM CT

Doctors may need support to cope with patient death

Doctors could benefit from support to help them cope with the trauma of patient death, says a psychology expert speaking at the Death, dying & disposal conference organised by the University of Bath today.

In a preliminary study, Dr Elaine Kasket from London Metropolitan University carried out detailed interviews with eight US physicians about their experiences of death. Half of those she spoke to wept as they recounted stories of traumatic death they had experienced as physicians, even though some of these events had occurred as much as 30 years ago.

There is an unwritten rule for doctors that suggests it is not wise or possible for them to feel emotions over a patients death because there is always another patient to help, said Dr Kasket.

Whilst this detachment might help when presented with a patient with a severe injury, I question how well it serves them in the longer term.

This emotional detachment is socially ingrained through medical school, and the cultures in both the UK and US medical establishments would see a physicians emotional response to death as a sign of weakness and even incompetence.

It feeds into this popular image of the doctor as some kind of superhuman ultimate rescuer of human life; unable to do his or her job if they give in to or even acknowledge their emotions......... Posted by: Emily      Read more         Source

September 12, 2007, 8:15 PM CT

Mathematics might save you a trip to the ER

Since the days of Hippocrates, people have known that certain illnesses come and go with the seasons. More recently, scientists have learned that these cyclic recurrences of disease, known as seasonality, are often correlation to the weather. In order to accurately predict when outbreaks of disease will occur, and how a number of people will be effected, Elena Naumova, PhD, associate professor in the Department of Public Heath and Family Medicine at Tufts University School of Medicine in Boston, and his colleagues, are studying seasonality by creating mathematical models based on environmental factors like outdoor temperature.

Until recently, public health workers and epidemiologists have eyeballed outbreak cycles relative to the weather in order to estimate when the next outbreak will strike a population, explains Naumova. But having a more accurate and reliable method of disease surveillance is crucial to forecasting outbreaks in order to implement warning systems, says Naumova. She and his colleagues have developed mathematical models that will more accurately assess seasonality in an effort to better predict when an outbreak will peak and how a number of people may fall ill.

Naumova and his colleagues tested their mathematical models with data gathered from the Massachusetts Department of Public Health on six diseases: giardiasis, cryptosporidiosis, salmonellosis, campylobacteriosis, shigellosis and hepatitis A, all characterized by nausea, diarrhea, abdominal cramping and often fever. Whereas a number of prior epidemiological studies investigating seasonality have used monthly data or quarterly data, Naumova and his colleagues used daily data, enabling the scientists to detect more subtle changes in disease patterns that may have been previously overlooked......... Posted by: Emily      Read more         Source

September 12, 2007, 6:09 PM CT

Genetic Link To Height

It became clear nearly a century ago that a number of genes likely influence how tall a person grows, though little progress, if any, has followed in defining the myriad genes. Now an international research team brings light to this age-old question by pinpointing a genetic variant linked to human height -- the first consistent genetic link to be reported.

The findings, reported in the September 2 advance online edition of Nature Genetics, stem from a large-scale effort led by researchers at the Broad Institute of MIT and Harvard, Children's Hospital Boston, the University of Oxford and Peninsula Medical School, Exeter.

In addition to being a textbook example of a complex trait, height is a common reason children are referred to medical specialists. Eventhough short stature by itself typically does not signal cause for concern, delayed growth can sometimes reflect a serious underlying health condition. "By defining the genes that normally affect stature, we might someday be able to better reassure parents that their child's height is within the range predicted by DNA, rather than a consequence of disease," said co-senior author Joel Hirschhorn, an associate member of the Broad Institute also affiliated with Children's Hospital Boston and Harvard Medical School......... Posted by: Emily      Read more         Source

September 11, 2007, 11:42 PM CT

Prescription labels geared toward pharmacies

The labels on most prescription drug containers highlight the pharmacys name or logo rather than instructions on how to take the medication, reports a new study in the September 10 issue of the Archives of Internal Medicine.

The Institute of Medicine estimates that 1.5 million medicine errors occur each year in the United States and poor labeling is one cause of the mistakes. While the Food and Drug Administration has some standards on what prescription labels must include, few regulations guide the format of the information, said lead author William Shrank, M.D., of Brigham and Womens Hospital at Harvard Medical School.

In the study, six pharmacies in four cities filled identically written prescriptions for four usually prescribed medications. The pharmacies included the two largest chains, two grocery stores and two independent pharmacies.

Shrank, who is with the Division of Pharmacoepidemiology and Pharmacoeconomics, and his colleagues reviewed 85 labels. The scientists found the pharmacy name or logo was the most prominent item on 84 percent of the labels, with an average 13.6-point font size. By comparison, the instructions averaged a 9.3-point size and medicine names averaged an 8.9-point font. Warning stickers were in a much smaller, 6.5-point font on average......... Posted by: Emily      Read more         Source

September 10, 2007, 10:11 PM CT

Embryonic Stem Cells Thrive When Shaken

Embryos spend much of their time in the womb bobbing along with a mother's movement, and, surprisingly enough, new research from the Georgia Institute of Technology and Emory University suggests that embryonic stem cells may develop much better under similarly shaky conditions.

Georgia Tech and Emory scientists discovered that moderate and controlled physical movement of embryonic stem cells in fluid environments, similar to shaking that occurs in the womb, improves their development and suggests that different types of movement could some day be used to control what type of cell they become. The research was reported in the recent issue of the journal Stem Cells.

"Embryonic stem cells develop under unique conditions in the womb, and no one has ever been able to study the effect that movement has on that development process," said Todd McDevitt, assistant professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University and head of the project. "While labs typically add all sorts of things to their cultures to influence cell direction, we were able to control the levels of differentiation and size of cell clusters by simply providing some fluid motion."

It all started with a fortunate accident. Rich Carpenedo, a graduate student and first author of the paper, discovered by chance that a dish of embryonic stem cells left on a common lab shaker (typically used to slowly mix samples) had developed in greater numbers and more uniformly than cells grown in a static environment (i.e. unshaken)......... Posted by: Emily      Read more         Source

September 6, 2007, 9:53 PM CT

Teaching Tools On Underage Alcohol Use

Efforts to halt underage drinking often focus on peer pressure and the prevention of risky behaviors, but the American Association for the Advancement of Science (AAAS) is undertaking a new federally funded project to give middle-school children a science-based understanding of what can happen to them if they use alcohol.

The three-year project, called The Science Inside Alcohol, will incorporate recent advances in neuroscience that have been shedding new light on how alcohol affects the body. It is funded by the National Institute on Alcohol Abuse and Alcoholism (NIAAA) with an initial grant of $253,000 and an anticipated total of $831,000.

The project will draw on AAASs long experience in developing standards and benchmarks for effective science education. It is getting underway as a new study in the recent issue of the journal Prevention Science suggests that teachers and parents should pay attention to alcohol prevention as early as the fourth grade. The analysis, by psychiatry expert John E. Donovan of the University of Pittsburgh, cited one national survey in which 6.9 percent of fourth graders and 12.9 percent of sixth graders reported alcohol use during the past 12 months.

While prevention messages, including warnings that alcohol can make youngsters do things they ordinarily would not do, are an important part of the effort to stop underage drinking, the new AAAS project will go beyond a purely prevention approach. It will offer students, and their adult teachers, a look at key scientific concepts correlation to alcohol use and abuse in simple, direct language......... Posted by: Emily      Read more         Source

September 6, 2007, 9:49 PM CT

How antibodies fight HIV

By furthering researchers understanding of the molecular mechanisms that separate the minority of successful HIV antibodies from the majority of ineffective antibodies, the work may have implications for future attempts to design an HIV vaccine.

The study was published on September 6, 2007, in the journal Nature.

This study is part of the effort to understand how protection against HIV occurs, says Dennis Burton, a professor at The Scripps Research Institute. If we really understand this, then we can design tailor-made vaccines in a way that has never been done before.

Eventhough vaccines have long been used with great success to prevent diseases, researchers are still learning about the exact mechanisms of how vaccines work and how the antibodies that vaccines prompt the body to create can neutralize a pathogen. The spread of HIV, which is resistant to most antibodies the body produces against it, has made fully understanding this method of action more urgent.

With this in mind, Burton and his colleagues sought to tease apart the action of the b12 antibody-one of the rare antibodies that protects against the HIV virus. The antibody, first identified by Burton, Scripps Research Professor Carlos Barbas III, and his colleagues in 1992, originally came from the bone marrow of a 31-year-old male who had been HIV positive without symptoms for six years......... Posted by: Emily      Read more         Source