Featured series 
Tag: Harvard Medical School
-
Health
Keeping synapses clean may hold key to fear-conditioning
As readers of introductory psychology texts know, animals easily learn to fear a harmless stimulus, such as a tone, if that stimulus is paired with a painful one, such as a foot shock. For this fear conditioning to take root in the brain, neurons located in the almond-shaped amygdala must become extraordinarily sensitized to the…
-
Health
Coffee cuts diabetes risk
More than 125,000 study participants who were free of diabetes, cancer, and cardiovascular disease at the start of a study were selected from the on-going Health Professionals Follow-up Study and the Brigham and Women’s Hospital-based Nurses Health Study. Some 41,934 men were tracked from 1986 to 1998 and 84,276 women from1980 to 1998 via food…
-
Health
New study identifies inhibitor of anthrax toxin
Findings by a research team could eventually lead to the development of a protease inhibitor drug, which in combination with antibiotics could be used to treat anthrax cases later in the disease, at a point when antibiotics alone are no longer effective. “Unlike most types of bacteria, bacillus anthracis has the ability to produce large…
-
Health
Sperm cells made in lab can fertilize eggs
Scientists injected laboratory-created sperm into eggs, and the resulting embryos grew to the point where they would normally be implanted into a womb. The experiment was done with mouse stem cells, but mice, genetically speaking, are so close to men, few scientists doubt that the same experiment can be done in humans. The breakthrough, made…
-
Health
Ritalin use in childhood may increase depression
A study, led by McLean Hospital’s William Carlezon and Susan Andersen, found that adult rats given Ritalin as juveniles behaved differently than their placebo-treated counterparts in a host of tests that reflect mood and attention. Published in the Dec. 15, 2003 issue of Biological Psychiatry, the study follows up previous work by the researchers showing…
-
Science & Tech
Minimally invasive prostate cancer treatment works as well as traditional techniques
Prostate cancer is the second most common cancer in men and the cause of approximately 29,000 deaths a year. Currently, the most common treatments for prostate cancer include radical prostatectomy (RP) and prostate brachytherapy using transrectal ultrasonography which delivers 100 percent of the radiation dosage to the entire prostate gland, thereby potentially compromising the health…
-
Health
Finding challenges predominant theory that arthritis prevents bone loss
For more than 30 years, it has been accepted in the medical community that women with arthritis are actually much less likely to experience accelerated bone loss. New findings, outlined in the December 2003 issue of the Journal of Bone and Joint Surgery, show a direct relationship between the diseases, potentially altering how this high-risk…
-
Health
Dramatic gains shown with moderate weight loss, exercise
A study of 35 obese people included three groups of volunteers; all were obese and had a body mass index above 30 kg/m2 and had insulin resistance. The first group in the study did not have diabetes; the second group had a condition known as impaired glucose tolerance and was at high risk for developing…
-
Health
Researchers find way to block SARS virus from entering cells and spreading infection
SARS – severe acute respiratory syndrome – is a viral respiratory illness caused by coronavirus, a family of viruses also implicated in the common cold. SARS is a distinct form of the coronavirus that was first identified in Asia in February 2003 and eventually resulted in a worldwide outbreak over a span of a few…
-
Campus & Community
New stage of memory found
It’s been known for a while that sleep helps consolidate certain memories; that’s probably a major purpose of sleep. But the latest experiments by Harvard Medical School researchers show that a good night’s rest can enhance your performance as much as 20-30 percent. Not all memories, just those of motor skills such as riding a…
-
Science & Tech
Puberty gene identified
A gene discovered by Harvard researchers and their colleagues in England makes a protein necessary to trigger a hormonal cascade that flows from the brain to the gonads. Without it, the researchers have shown, humans and mice do not become sexually mature. Stephanie Seminara, an assistant professor of medicine at Harvard Medical School, called the…
-
Health
Smoking increases bleeding into the brain, study finds
A research team at Brigham and Women’s Hospital (BWH) found that stroke risk for women increased proportionately with the number of cigarettes smoked each day. In contrast, women who stopped smoking were at no additional risk. The findings appeared in the Nov. 13, 2003 online edition of the journal, Stroke, a publication of the American…
-
Health
Regeneration of insulin-producing islets may lead to diabetes cure
Type 1 diabetes develops when the body’s immune cells mistakenly attack the insulin-producing islet cells of the pancreas. As islet cells die, insulin production ceases, and blood sugar levels rise, damaging organs throughout the body. Cells from an unexpected source, the spleen, appear to develop into insulin-producing pancreatic islet cells in adult animals. This surprising…
-
Health
Physicians report trouble obtaining specialty services for uninsured
A research team surveyed more than 2,000 physicians at U.S. academic health centers who had provided direct patient care during the preceding year. Among the questions asked were whether the physicians were unable to admit uninsured patients or had to limit such patients’ hospital care; how often they could obtain specialty referrals or advanced services…
-
Health
Study challenges proposed changes to clinical definition of mental illness
As the American Psychiatric Association prepares for the Diagnostic and Statistical Manual of Mental Disorders’s fifth edition, there is debate over whether to eliminate milder forms of diseases to prevent overtaxing the mental health care system. According to Ronald Kessler, HMS professor of health care policy, tightening the DSM’s definitions is a serious matter. His…
-
Health
Is your heart in the right place?
In a frog, the position of the heart is determined within the first hour in the womb, Harvard scientists have discovered. Researchers all over the world believe that frogs and humans develop in a similar way. Experiments show, for example, that some of the same mechanisms put the hearts of both creatures on the left…
-
Health
Did life originally spring from clay?
While the research is a far cry from proving that humans sprang from clay, as some creation myths assert, it does provide a possible mechanism for explaining how life initially arose from nonliving molecules. Researchers at the Howard Hughes Medical Institute and Massachusetts General Hospital showed that the presence of clay aids naturally occurring reactions…
-
Health
Enzyme responsible for protein’s ‘Jekyll-and-Hyde’ personality
Normally, a protein regulates when and how body parts develop, but when mutated, it triggers a rare, often-lethal infant leukemia called mixed lineage leukemia. The newly identified protease enzyme, Taspase1, plays a key role in the MLL protein’s dual-personality. (A protease enzyme cuts protein molecules into smaller pieces). Blocking Taspase1, Dana-Farber Cancer Institute researchers say,…
-
Health
Matrix-buster inhibitor has second way to throttle angiogenesis
Matrix metalloproteinases (MMPs) and their regulators, the tissue inhibitors of metalloproteinases (TIMPs), form an intriguing partnership. MMPs work by breaking down the dense matrix surrounding cells, freeing them to wander the body during processes like metastasis and angiogenesis. TIMPs rein in the MMPs, essentially cutting off the supply of migrating cancer or endothelial cells. Given…
-
Campus & Community
Low-carb more effective than low-fat
A study put three groups of dieters on different regimens. They included a low-fat group, a low-carbohydrate group that ate the same number of calories, and a third group on a similar low-carbohydrate plan that included 300 extra calories a day. The low-carbohydrate dieters lost more weight than low-fat dieters despite eating 25,000 extra calories…
-
Campus & Community
Breast cancers tied to brain survival
A gene produces a protein that evidently protects cancer cells in the same way it shields brain cells from damage caused by diseases like Alzheimer’s and strokes. “The same substance can be doubly harmful to some people with invasive breast cancer because it protects the tumor cells from death,” notes Kornelia Polyak, an assistant professor…
-
Health
Compound traces brain plaques in real time
Alzheimer’s disease is notoriously difficult to diagnose. Though sophisticated functional and cognitive tests can help, they often fail to distinguish between Alzheimer’s and other non-amyloid-based dementias, particularly frontotemporal dementia. The ability to measure plaques in vivo would not only provide clinicians with an immediate and reliable diagnosis, but over time would allow them to gauge…
-
Health
Innate signal sparks homing of T cells
The results of three studies published together in the Aug. 31, 2003 online edition of Nature Immunology help explain the uncanny ability of T cells to home to problem areas in the body and suggest potential new mechanisms to treat inflammatory diseases, such as asthma. When one fast-acting lipid hits the panic button about a…
-
Health
Stages of memory described in study
“To initiate a memory is almost like creating a word processing file on a computer,” explains researcher Matthew Walker, instructor of psychiatry at Beth Israel Deaconess Medical Center and Harvard Medical School. “Once the file has been created, if you don’t hit the ‘save’ button before shutting off the computer it will be lost. Our…
-
Health
Dieting may actually promote weight gain in children
The prevalence of overweight and obese children has increased by 100 percent since the 1980s. Americans spend about $33 billion a year on weight loss products and services, however, only about one in five adults follow recommended diet guidelines, possibly explaining why most people fail to maintain long-term weight control. It now appears that casual…
-
Health
Hold that penicillin
“The threat of resistance to antibiotics by bacteria increased so dramatically from the 1970s to the mid-1990s that the Centers for Disease Control and Prevention (CDC) labeled it a national public health crisis,” said Jonathan Finkelstein of the Harvard Medical School and Harvard Pilgrim Health Care in Boston. The CDC has called on doctors to…
-
Health
Close interaction seen between blood vessel development and fat tissue formation
Findings from researchers at Massachusetts General Hospital could eventually help to solve problems ranging from cancer, to obesity, to the development of replacement organs. The findings involve the key physiological processes of angiogenesis, the growth of new blood cells, and adipogenesis, the development and growth of fat cells, which appear to be so closely interwoven…
-
Health
Osteoporosis appears to be poorly treated after fractures
Hip and wrist factures, suffered by more than 550,000 individuals annually, are a leading cause of hospitalization and death in the elderly. Often one fracture from osteoporosis leads to another, but with the help of medications, this risk can be cut by as much as 60 percent. However, as outlined in the October issue of…
-
Science & Tech
Blue light special
Jet-setters and shift workers now sit in front of glaring white lights to readjust their body rhythms and avoid sleep and alertness problems. New experiments condcuted by Harvard University researchers suggest that they would be better off sitting in front of blue lights. The research also contradicts what many scientists believed for years, that the…
-
Health
Longer life for blood
Blood platelets, which are transfused into those who lose too much blood from wounds, major surgery, or cancer treatments, can be kept for only five days. Then they must be discarded, a waste of hundreds of millions of dollars a year. Refrigeration can extend the shelf life to about a month, but when this cold…