People sometimes use indoor tanning in the belief that this will prevent burns when they tan outdoors. However, indoor tanning raises the risk of developing melanoma even if a person has never had burns from either indoor or outdoor tanning, according to a study published May 29 in the JNCI: Journal of the National Cancer Institute.

MINNEAPOLIS – People with high levels of cynical distrust may be more likely to develop dementia, according to a study published in the May 28, 2014, online issue of Neurology®, the medical journal of the American Academy of Neurology.

Cynical distrust, which is defined as the belief that others are mainly motivated by selfish concerns, has been associated with other health problems, such as heart disease. This is the first study to look at the relationship between cynicism and dementia.

Heroin is popular again, though not for reasons you expect. Gone are the days of desperate junkies in poverty settings. Now it is primarily cheap young urban professionals.

Few studies on the demographics of present day heroin users have compared them to heroin users 40 to 50 years ago. In the 1960s, heroin junkies were primarily young men from minority groups living in urban areas. Theodore J. Cicero, Ph.D., of Washington University, St. Louis, and colleagues analyzed data on nearly 2,800 patients from an ongoing study that used self-reported surveys from patients with a heroin use/dependence diagnosis entering treatment centers and also from patients who completed a more detailed interview (n=54).  

Men with gender dysphoria, commonly called gender identity disorder, are born as males but behave as and identify with women and want to change sex.

Around puberty, the testes of men start to produce androstadienone, a musky-smelling steroid produced by men
as a breakdown product of testosterone. Men release it in their sweat, especially from the armpits. Its only known function is to work like a pheromone; when women smell androstadienone, their mood tends to improve, their blood pressure, heart rate, and breathing go up, and they may become aroused. 
 

Evidence for massive and abrupt iceberg calving in Antarctica dating back 19,000 to 9,000 years ago is based on an analysis of new, long deep sea sediment cores extracted from the region between the Falkland Islands and the Antarctic Peninsula. 

The study in Nature documents that the Antarctic ice sheet is unstable and can abruptly reorganize Southern Hemisphere climate and cause rapid global sea level rise. 

Why are some 75-year-olds downright spry while others can barely get around?  Some people who smoke look old from a young age while others don't.

Part of the explanation, say researchers writing in Trends in Molecular Medicine is differences from one person to the next in exposure to harmful substances in the environment. 

A birth date is a chronological age but it might mean little in terms of the biological age of our body and cells. The researchers say that what we need now is a better understanding of the chemicals involved in aging and biomarkers to measure their effects.

A mechanism that enables the development of resistance to Acute Myeloid Leukemia (AML) anticancer drugs, thereby leading to relapse, has been identified by Kathy Borden of the University of Montreal's Institute for Research in Immunology and Cancer (IRIC) and her collaborators. Kathy Borden is a Principal Investigator at IRIC and a professor at the university's Department of Pathology and Cell Biology. The development of drug resistance is one of the main problems in clinical oncology and the cause of relapse in many patients.

NEW YORK, NY (May 21, 2014) — The overall number and nature of mutations—rather than the presence of any single mutation—influences an individual's risk of developing schizophrenia, as well as its severity, according to a discovery by Columbia University Medical Center researchers published in the latest issue of Neuron. The findings could have important implications for the early detection and treatment of schizophrenia.

Tai Chi is a traditional Chinese pastime that had its origins in self-defense. Like with many sports and hobbies, its benefits in relaxation and fitness are well-documented.

A new paper in Cell Transplantation adds to its benefits, finding in a small study that it increased a cluster of differentiation 34 expressing (CD34+) cells, a stem cell important to a number of the body's functions and structures.

Three groups of young people were tested to discover the benefits of Tai Chi, brisk walking or no exercise. 

In most sports, youth helps. The adage was that if an older person can do it better than a younger person, it isn't a sport.

But the lines of performance are lot more blurry today and youth is not a barometer. Lots of high school students can jump right to the NBA, and the first round draft pick in the NFL college draft is likely to be starting the next summer, but baseball drafts aren't big media events because no one drafted is likely to get called up for a few years. Baseball takes more practice.

And when it comes to marathons, old people really blow the sports curve. They even turn it into a U-shape; a 55- or 60-year-old runner will often finish in the same time as an 18-year-old.