HealthDay, 11/3/08 (http://www.healthday.com/Article.asp?AID=620935)

Children who live in areas of the United States that get a lot of precipitation appear to have a higher risk of developing autism, a new study suggests.

Because these children may spend more time indoors or because rain brings chemicals in the atmosphere to the ground, they might be exposed to environmental triggers that can trigger a genetic predisposition to autism, the researchers say.

“There seems to be a strong association between precipitation and autism diagnosis rates,” said lead researcher Michael Waldman, a professor of economics at the Johnson Graduate School of Management at Cornell University.

Waldman, whose son was diagnosed with autism spectrum disorder, isn’t saying that rain causes the condition. “Our finding strongly suggests that there is some factor which is positively correlated with precipitation, which is serving as a trigger for autism,” he said.

One possible explanation for this correlation is vitamin D deficiency, Waldman said. “There is a fair amount of research that vitamin D deficiency in young children causes problems. As children aren’t outside as much, they aren’t getting enough vitamin D, and that’s serving as a trigger for autism,” he said.

Another possibility is children are spending too much time watching TV or videos, Waldman said. “There are various papers showing associations between early childhood television viewing and various problems concerning cognitive outcomes, sleep problems, behavior problems, etc.,” he noted.

A third possibility is exposure to chemicals in the home which trigger autism, Waldman said. In addition, there may be a chemical or chemicals in the upper atmosphere that are transported to the surface by precipitation.

There is debate about whether autism is caused by genetics alone or genetics and the environment, Waldman said. “Our results are inconsistent with it being just genetic.”

The report was published in the November issue of the Archives of Pediatrics & Adolescent Medicine.

For the study, Waldman’s team looked at the prevalence of autism among children in California, Oregon and Washington. They also used data from the National Climatic Data Center to calculate the average annual rainfall by county in these states.

The researchers found among school-aged children in these states that the prevalence of autism rose as the amount of precipitation increased. In fact, the prevalence in autism increased up to 30 percent in the rainiest counties.

Over the past three decades, the number of children diagnosed with any form of autism has increased from one in 2,500 children to one in 150 children. Some of the increase is most likely due to better diagnosis and the changing definition of autism, which now encompasses a variety of conditions called autism spectrum disorder.

Waldman’s group, however, insists that a real increase in the numbers of autistic children cannot be ruled out.

Richard Lathe, an autism expert from Pieta Research in Edinburgh, Scotland, thinks that Waldman might be on to something.

“Nevertheless, one must be vigilant, because statistical correlations do not necessarily imply causality,” Lathe said. “This caveat aside, the authors demonstrate, with better than 99 percent certainty, that the correlation is not by chance.”

Lathe thinks the most likely explanation for the association between autism and rain is that rain carries chemicals in the atmosphere to the ground.

“This explanation is plausible,” Lathe said. “Emissions from manufacturing industries, power plants, and from domestic waste incineration generally rise to the troposphere to be diluted into the large volume of the atmosphere. Precipitation can dump this load back on the land, to be absorbed by plants and animals in the food chain,” he said.

One possibility that needs to be addressed further is that exposure need not be in the child, Lathe said. “There has been a suggestion that maternal exposure to environmental toxins might contribute to autism in children,” he said.

These results are not definitive evidence in favor of the hypothesis that autism has an environmental trigger, but the results are consistent with the hypothesis, Lathe said. “For the future, one feels it will be essential to study levels of toxins in soil, crop and food samples from the different counties investigated in the Waldman study. A positive correlation would greatly reinforce the environmental hypothesis,” he said.

Dr. Noel S. Weiss, a professor of epidemiology at the University of Washington in Seattle, and author of an accompanying journal editorial, thinks the results of the study need to be taken with a grain of salt.

“This is a course analysis,” Weiss said. “There are difficulties, because autism is not that unequivocally defined, and the criteria for diagnosis can vary from place to place and over time. The message is really to other scientists who might examine this relationship.”

Weiss isn’t convinced that the association between autism and precipitation is real. “It could be, but I don’t think so,” he said. “But it’s probably worth looking into.”

On the front page of the Washington Post, (11/4, HE1) Health section, staff writer Tomoeh Murakami Tse writes that hyperemesis gravidarum is “a severe form of pregnancy sickness characterized by persistent nausea and vomiting as well as significant weight loss, often more than five percent. It occurs in about three to 20 of every 1,000 pregnancies, hospitalizing more than 30,000 women a year in the United States, according to studies and government statistics.”

Those “with the condition can suffer from dehydration, malnutrition, electrolyte imbalance and, in severe instances, neurological disorders, spleen tearing, kidney failure, and lung collapse. Before intravenous fluid treatment became available, it was not uncommon for women to die from hyperemesis. It can affect the unborn baby, too: Some researchers have linked the condition with restricted fetus growth, preterm delivery, and low birth weight.”

At present, “no one knows exactly what causes nausea and vomiting in pregnancy, but elevated hormone levels are widely thought to be at fault.”

AP, 11/3/08 (http://www.washingtontimes.com/news/2008/nov/03/study-women-lead-men-in-bacteria-hands-down/):

  Wash your hands, folks, especially you ladies. A new study found that women have a greater variety of bacteria on their hands than men do. And everybody has more types of bacteria than the researchers expected to find.

“One thing that really is astonishing is the variability between individuals, and also between hands on the same individual,” said University of Colorado biochemistry assistant professor Rob Knight, a co-author of the paper.

“The sheer number of bacteria species detected on the hands of the study participants was a big surprise, and so was the greater diversity of bacteria we found on the hands of women,” added lead researcher Noah Fierer, an assistant professor in Colorado’s department of ecology and evolutionary biology.

The researchers aren’t sure why women harbored a greater variety of bacteria than men, but Fierer suggested it may have to so with the acidity of the skin. Knight said men generally have more acidic skin than women.

Other possibilities are differences in sweat and oil gland production between men and women, the frequency of moisturizer or cosmetics applications, skin thickness or hormone production, he said.

Women also may have more bacteria living under the surface of the skin where they are not accessible to washing, Knight added.

Asked if guys should worry about holding hands with girls, Knight said: “I guess it depends on which girl.”

He stressed that “the vast majority of the bacteria we have on our body are either harmless or beneficial … the pathogens are a small minority.”

The researchers took samples from the palms of 51 college students _ that’s 102 hands _ and tested the samples using a new, highly detailed system for detecting bacteria DNA.

They identified 4,742 species of bacteria overall, only 5 of which were on every hand, they report on Monday’s online edition of Proceedings of the National Academy of Sciences.

The average hand harbored 150 species of bacteria.

Not only did individuals have few types of bacteria in common, the left and right hands of the same individual shared only about 17 percent of the same bacteria types, the researchers found.

The differences between dominant and non-dominant hands were probably due to environmental conditions like oil production, salinity, moisture or variable environmental surfaces touched by either hand of an individual, Fierer said.

Knight said the researchers hope to repeat the experiment in other countries where different hands are assigned specific tasks.

While the researchers stressed the importance of regular hand washing, they also noted that washing did not eliminate bacteria.

“Either the bacterial colonies rapidly re-establish after hand washing, or washing (as practiced by the students included in this study) does not remove the majority of bacteria taxa found on the skin surface,” the researchers said in their report.

While the tests could determine how many different types of bacteria were present, they could not count the total amount of bacteria on each hand.

The research was funded primarily by the National Institutes of Health and the National Science Foundation.

MedWire, 11/4/08 (http://www.medwire-news.md/news/article.aspx?k=48&id=78709)

“People with asthma may benefit from Tai Chi training to improve their asthma control and exercise performance, researchers report at Chest 2008 – the 74th annual international scientific assembly of the American College of Chest Physicians, held in Philadelphia, Pennsylvania, USA.

Tai Chi is a traditional Chinese exercise that involves slow, fluid movements and set postures, and is thought to improve strength, balance, and posture, and aid relaxation.

To investigate whether Tai Chi can benefit people with asthma, Sumalee Kiatboonsri and colleagues from Ramathibodi Hospital in Bangkok, Thailand, studied 17 patients with persistent asthma who were assigned to complete a 6-week Tai Chi Qigong training program.

All patients underwent respiratory health and exercise assessments at the start and end of the Tai Chi training program.

The researchers found that all of the participants showed significant improvements in peak flow variability, asthma control test score, negative inspiratory pressure, 6-minute walk distance, and quality of life over the course of the study.

Furthermore, patients also increased their maximum work rate, maximum oxygen consumption, and exercise endurance time compared with baseline.

Results of a questionnaire also revealed that Tai Chi training was associated with significant improvements in the participants’ quality of life…”