Here are some of the latest health and medical news developments, compiled by editors of HealthDay:
Study Identifies Brain Chemical Involved in Exercise "High"
Yale University scientists have identified a brain chemical associated with the natural "high" of exercise and suggest that a drug based on that chemical could provide an effective treatment for depression, BBC News reported.
The researchers found that a gene called VGF -- located in the brain's hippocampus -- is more active during exercise. The gene is linked to a growth factor chemical involved in the development of nerve cells.
The Yale team then made a version of this chemical and tested it in mice. It seemed to affect the rodents' behavior in a way somewhat similar to the way antidepressants affect humans, BBC News reported.
The research appears in the journal Nature Medicine.
Cancer Cells Softer Than Normal Cells
The surfaces of living cancer cells are more than 70 percent softer than those of healthy cells, says an American study in the journal Nature Nanotechnology. The softer surfaces were detected in lung, breast and pancreatic cancers.
The finding by University of California, Los Angeles scientists could help increase detection of cancer cells that might otherwise escape notice, Agence France-Presse reported.
For this study, the researchers collected body fluid from suspected cancer patients and used atomic force microscopes to apply pressure to individual cells. The cells' surfaces were tested using a sharp probe attached to a mechanical arm.
"Our work shows that mechanical analysis can distinguish cancerous cells from normal ones even when they show similar shapes," the researchers concluded. They said the increased softness that occurs when normal cells become cancerous makes it easier for cancer cells to spread to other parts of the body, AFP reported.
China Reports 17th Bird Flu Victim
China has reported its 17th human victim of H5N1 bird flu, the country's official Xinhua news agency said Monday.
The 24-year-old man died Sunday at a hospital in southern province of Jiangsu. The news agency said tests confirmed that the man was infected with the H5N1 virus, the Associated Press reported.
The victim had no known contact with infected poultry, and there have been no reported outbreaks of bird flu in Jiangsu province.
The H5N1 virus first appeared in 2003 and remains a dangerous threat throughout Indonesia and in parts of Bangladesh, China, Egypt, Nigeria and Vietnam, the AP reported.
Genes Linked to Psoriasis and Lupus Identified
Genes linked to psoriasis and lupus have been identified by scientists. These new findings appear online in the journal Nature Genetics.
Learning more about genes associated with these diseases may help in the development of new treatments.
In one study, researchers led by John Armour of the University of Nottingham in Britain found that people with the skin disease psoriasis had significantly more copies of a gene called beta-defensin. It's known that this gene can trigger skin inflammation in response to infections, Agence France-Presse reported.