Docs hope to tailor treatments to genes
Tue, 25 Sep 2007 20:05:03 GMTBy MARIA CHENG, AP Medical Writer
BARCELONA, Spain - The treatment that more cancer patients receive may one day depend on their genes. With an increasing number of biological clues available, doctors hope they will be able to customize more patients' treatments based on their genetic profiles.
In research presented at a meeting of the European Cancer Organization in Barcelona, experts said this week that these clues will help doctors determine not only which patients will probably develop cancer, but even those who will relapse, or be suitable for specific treatments.
"We are going to witness a revolution in cancer treatment," said Dr. Martine Piccart, head of medicine at the Institut Jules Bordet in Belgium. "In a few years, we will be able to fully demonstrate how powerful these new technologies are."
The real test, however, will be if doctors can then figure out what to do next.
"It's never encouraging to say to a patient that she's going to do poorly because of her genes," Piccart said. "We need to be able to offer patients an effective treatment."
Piccart and colleagues have been working to confirm the genetic sequences for women susceptible to breast cancer.
Tailoring treatment based on patients' genes is being used now on a limited basis. Doctors have been deciding how to treat women with breast cancer depending on their tumor type for the last few years. A simple genetic test can identify breast cancer patients who will actually benefit from chemotherapy, making the toxic side effects worthwhile.
But learning more about breast cancer has also given experts new tools to fight other cancers.
A study presented at the Barcelona meeting Tuesday found an unexpected twist: patients with a certain overactive breast cancer gene were also less likely to respond to chemotherapy for lung cancer.
"We know quite a bit about breast cancer genes, and now we're looking into the black box of what role they might play in other cancers," said Dr. Gordon McVie, a cancer expert at the European Institute of Oncology.
The problem, McVie said, is that even though researchers may understand a little about what a thousand of the genes involved in cancer do, there are about 31,000 others that they don't.
Other studies presented in Barcelona on Tuesday identified genes that could triple a woman's risk of ovarian cancer, as well as molecular profiling to predict which colon cancer patients would benefit from chemotherapy.
Cancer is an incredibly complicated disease, and is influenced by other variables like diet and environmental exposure. Even if researchers can identify the genetic components responsible, many factors remain beyond doctors' control.
"We haven't had any big genetic hits," McVie said, explaining that while scientists have identified genes that predispose people to cancers including breast, bowel, ovarian and colon, those make up only a small amount of all cancers.
"Cracking the genetic code is still a very imprecise science," he said.
Also, on Monday, German researchers said they had developed a test to identify cancer cells circulating in the blood of breast cancer patients. That could potentially enable doctors to catch cancer cells en route to another location — and give them time to intervene to prevent a tumor.
Dr. Julia Juckstock and colleagues at the University of Munich analyzed blood samples from 1,767 women with breast cancer before treatment and compared them to samples taken after about half of them had completed chemotherapy. Preliminary results found evidence of tumor cells in transport in less than 10 percent of the treated patients.
"This is a fascinating development," said Dr. John Smyth, a professor of medical oncology at the University of Edinburgh, who was unconnected to the Munich study.
Instead of a blanket approach to treatment, Smyth said that the test could help doctors pinpoint those women in whom breast cancer was likely to spread and needed extra care.
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On the Net:
European Cancer Organization: http://www.ecco-org.eu/
ADA gives seal to Wrigley sugarfree gum
Tue, 25 Sep 2007 20:10:27 GMTBy DAVE CARPENTER, AP Business Writer
CHICAGO - The nation's largest dentist group now says gum can be good for you, as long as it's sugar-free. The American Dental Association said Tuesday it has awarded its seal of acceptance to Wrigley sugar-free gums Orbit, Extra and Eclipse — based on studies funded at least partially by the maker of Wrigley gums, Chicago-based Wm. Wrigley Jr. Co.
It's the first time the ADA has allowed its seal to appear on gum after clearing it for thousands of other products since 1930.
The ADA said its independent review of the studies confirms those three gums have been shown to help prevent cavities, reduce plaque acid and strengthen teeth.
It said studies submitted by Wrigley showed that chewing those gum products for 20 minutes three times a day after meals increases saliva production. Saliva, the ADA said, helps neutralize and wash away plaque acid and bathes the teeth in minerals such as calcium, phosphate and fluoride, which are known to strengthen tooth enamel and help prevent cavities.
Clifford Whall, director of the ADA seal of acceptance program, said its council on scientific affairs found the studies, which focused solely on Wrigley products, had followed scientific principles.
"The council has looked at the body of data and concluded that there are some health benefits to chewing these products three times a day for 20 minutes," he said.
Wrigley paid $36,000 to submit its evaluation material — $12,000 per product. ADA also said Wrigley spends $35,000 to $45,000 in exhibit booth space at its annual meeting, advertising in its publications and on other sponsorships. It also pays $25,000 to help sponsor an ADA health screening program.
Consumer advocate Peter Lurie said the dental association should test other products before issuing such a seal, with the system appearing to be biased in favor of large companies that can afford the clinical studies.
"As long as the testing process and the criteria for receipt of a seal is unclear, the exact meaning of the ADA's seal will remain obscure," said Lurie, deputy director of the Health Research Group at Public Citizen, the nonprofit consumer advocacy group founded by Ralph Nader.
Whall said the program exists solely to inform consumers and dentists about whether products do what their manufacturers say they do. The seal currently appears on various toothpaste, dental floss and oral rinse products.
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On the Net:
American Dental Association: http://www.ada.org
Wrigley site on chewing gum benefits: http://www.gumisgood.com
WHO Cholera outbreak in Iraq spreading
Tue, 25 Sep 2007 19:55:33 GMTGENEVA - A cholera outbreak in Iraq is spreading, the World Health Organization said Tuesday, with new cases confirmed in Baghdad, Basra and for the first time three northern districts.
The number of confirmed cases has now reached 2,116, WHO said. Just a day earlier a WHO official put the number of confirmed cases at 1,652. Eleven people have died of the disease so far.
"It shows that people are moving, and when people are moving they are spreading cholera," said Claire-Lise Chaignat, a cholera expert at WHO.
The global health body estimates that more than 30,000 people have fallen ill with acute watery diarrhea, which may later be confirmed as cholera.
More than two-thirds of confirmed cases are in the northern province of Kirkuk, where cholera was first reported on Aug. 13, WHO said.
While the number of deaths from the disease has so far been low, "it continues to spread across Iraq and dissemination to as yet unaffected areas remains highly possible," WHO said.
A new case in Baghdad has taken the number of confirmed infections there to two, said WHO spokeswoman Fadela Chaib. On Monday a woman in the Iraqi capital died from the disease.
Six cases have also been confirmed in Tikrit and two have been confirmed in Mosul, both northwest of Baghdad. One case has been confirmed in Dahuk, in the far north of the country near the Turkish border.
Chaignat said a further confirmed case in Basra was likely unrelated to the other outbreaks as cholera is endemic to the southern district.
Cholera is a gastrointestinal disease that is typically spread by drinking contaminated water and can cause severe diarrhea that in extreme cases can lead to fatal dehydration.
Many governments prefer to report outbreaks under the heading of acute watery diarrheal diseases rather than admit the existence of cholera in their country.
It can be prevented by treating drinking water with chlorine and improving hygiene conditions.
Study Acupuncture works for back pain
Tue, 25 Sep 2007 03:09:04 GMTBy CARLA K. JOHNSON, Associated Press Writer
CHICAGO - Fake acupuncture works nearly as well as the real thing for low back pain, and either kind performs much better than usual care, German researchers have found. Almost half the patients treated with acupuncture needles felt relief that lasted months. In contrast, only about a quarter of the patients receiving medications and other Western medical treatments felt better.
Even fake acupuncture worked better than conventional care, leading researchers to wonder whether pain relief came from the body's reactions to any thin needle pricks or, possibly, the placebo effect.
"Acupuncture represents a highly promising and effective treatment option for chronic back pain," study co-author Dr. Heinz Endres of Ruhr University Bochum in Bochum, Germany, said in an e-mail. "Patients experienced not only reduced pain intensity, but also reported improvements in the disability that often results from back pain and therefore in their quality of life."
Although the study was not designed to determine how acupuncture works, Endres said, its findings are in line with a theory that pain messages to the brain can be blocked by competing stimuli.
Positive expectations the patients held about acupuncture — or negative expectations about conventional medicine — also could have led to a placebo effect and explain the findings, he said.
In the largest experiment on acupuncture for back pain to date, more than 1,100 patients were randomly assigned to receive either acupuncture, sham acupuncture or conventional therapy. For the sham acupuncture, needles were inserted, but not as deeply as for the real thing. The sham acupuncture also did not insert needles in traditional acupuncture points on the body and the needles were not manually moved and rotated.
After six months, patients answered questions about pain and functional ability and their scores determined how well each of the therapies worked.
In the real acupuncture group, 47 percent of patients improved. In the sham acupuncture group, 44 percent did. In the usual care group, 27 percent got relief.
"We don't understand the mechanisms of these so-called alternative treatments, but that doesn't mean they don't work," said Dr. James Young of Chicago's Rush University Medical Center, who wasn't involved in the research. Young often treats low back pain with acupuncture, combined with exercises and stretches.
Chinese medicine holds that there are hundreds of points on the body that link to invisible pathways for the body's vital energy, or qi. The theory goes that stimulating the correct points with acupuncture needles can release blocked qi.
Dr. Brian Berman, the University of Maryland's director of complementary medicine, said the real and the sham acupuncture may have worked for reasons that can be explained in Western terms: by changing the way the brain processes pain signals or by releasing natural painkillers in the body.
In the study, the conventional treatment included many methods: painkillers, injections, physical therapy, massage, heat therapy or other treatments. Like the acupuncture patients, the patients getting usual care received about 10 sessions of 30 minutes each.
The study, appearing in Monday's Archives of Internal Medicine, used a broad definition for low back pain, but ruled out people with back pain caused by spinal fractures, tumors, scoliosis and pregnancy.
Funding came from German health insurance companies, and the findings already have led to more coverage in Germany of acupuncture.
In the United States, some health plans cover acupuncture for some conditions, but may require pre-approval, according to the National Center for Complementary and Alternative Medicine. An acupuncture session can cost $45 to $100, Young said.
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On the Net:
Archives: http://www.archinternmed.com
In sex life of jumping spiders size matters
Mon, 24 Sep 2007 17:57:38 GMTby Marlowe Hood
PARIS - From post-coital cannibalism to love at first sight, the sex life of the African jumping spider is full of surprises, according to a new study.
But none is more unexpected than this, say researchers who studied the blood-gorging Evarcha culicivora up close and personal: while virgin females are attracted to meatier mates, a bit of experience sees them switch to smaller partners.
In this and other ways, the jumping spider, native to East Africa, is in a class of its own when it comes to sex, according to a study in the current issue of the scientific journal Ethology.
For starters, both males and females play a roughly equal role in choosing partners, an aberration in the eight-legged world of Arachnida.
That equal opportunity behavior extends to two-way cannibalism as well, with males consuming their loved ones only slightly more often as the reverse.
For spiders that go in for that sort of thing, females gobbling up their sex partners is the norm.
Another finding that surprised a team of researchers led by Simon Pollard, a biologist at the Cantebury Museum in Christchurch, New Zealand, was that E. culicivora -- armed with eye-sight &;unrivalled by other animals in their size range&; -- picks its partner based on looks and size alone.
And here is where things get strange.
Female adult African jumping spiders vary in size between three and six millimetres, while males range between four and seven, giving rise to the possibility of larger males mating with smaller females and vice versa.
In a series of laboratory experiments, Pollard showed that in three of four possible scenarios, an individual E. culicivora preferred a partner with an extra millimetre or two on its frame.
Virgin females, along with both experienced and inexperienced males, were all more than twice as likely to opt for a meatier mate.
But females that had copulated once before saw things differently: two out of three made a bee-line for the smallest male in sight.
&;It is as though females start out prepared to take the risk in choosing larger males,&; knowing they may be eaten as a post-sex snack, Pollard notes in the study. &;And then, once mated, they become less inclined to take the risk again.&;
But exactly why experienced females prefer to practice &;safer sex&; the second time around, admits Pollard, &;is currently unknown.&;
To test his hypothesis that E. culicivora makes mate-choice decision based on looks alone, Pollard perched two life-like embalmed specimens of different sizes in come-hither postures inside a large cage, with a single plastic tube leading from an entryway to each one.
The researchers made sure that the spider choosing between the two had a gander at both potential partners before counting the results, which showed that decisions were based on static looks alone.
To ensure that other factors were not coming into play, they repeated the experiment, but this time with live spiders. The results were the same.
The African jumping spider feeds mainly on small lake flied and blood-gorged female mosquitos, which means that vertebrate blood is an important part of their diet.
Omega3 fatty acids protect against diabetes study
Tue, 25 Sep 2007 20:39:01 GMTBy Julie Steenhuysen
CHICAGO - A diet rich in fish and other sources of omega-3 fatty acids helped cut the risk that children with a family history of diabetes would develop the disease, U.S. researchers said on Tuesday.
&;It is a relatively large effect,&; said Jill Norris, whose study appears in the Journal of the American Medical Association.
&;It is exciting because it suggests we might be able to develop nutritional interventions to prevent diabetes.&;
Type 1 diabetes, formerly called juvenile diabetes, is the most common form of diabetes in children. It occurs when the immune system goes haywire and starts attacking insulin-producing cells in the pancreas.
No one knows exactly what triggers this process, but heredity and environmental factors such as diet are thought to play a role.
Several studies in animals have suggested that omega-3 fatty acids -- which are found in fish, flaxseed oil, walnuts, soybeans and other foods -- may help.
To test whether omega-3 fatty acids offer a potential protective effect, Norris and colleagues at the University of Colorado at Denver studied 1,770 children between 1994 and 2006 who were deemed at high risk for diabetes because of genetic tests or because they had a sibling or parent with type 1 diabetes.
Data about their dietary intake were collected in food frequency surveys.
Their blood was tested at least once a year for what is known as islet autoimmunity -- the development of antibodies made by the immune system that attack insulin-producing cells in the pancreas. These antibodies are considered a strong predictor of type 1 diabetes.
Fifty-eight children in the study developed these antibodies.
Overall, the researchers found at-risk children who ate a lot of foods rich in omega-3 were 55 percent less likely to have pancreatic islet autoimmunity.
&;This is the first study to show this,&; Norris said in a telephone interview. &;This is all omega-3 fatty acids, not just the kind that are found in fish.&;
To make sure parents in the study were accurately reporting the children's food intake, Norris and colleagues tested for the presence of omega-3 fatty acids in blood cell membranes of 244 of the children.
In that group, children with omega-3 fatty acids in their blood cell membranes had a 37 percent decreased risk of having islet autoimmunity.
&;It is certainly not time to make any recommendations until we can see this in other populations,&; Norris said, but added that it is a very promising result.
Omega-3 fatty acids interfere with enzymes that play a role in inflammation, a potential trigger for type 1 diabetes.
At least 194 million people in the world have diabetes, and the World Health Organization expects that number to rise to more than 300 million by 2025. Most of these people have type 2 diabetes, which is linked with poor diet and lack of exercise.
People with type 1 diabetes often must take insulin injections to control blood sugar levels.
