Friday, March 02, 2007

Common cold virus 'kills' cancer

The common cold virus is about to be put to the test as a new weapon against cancer. Australian studies have found the Coxsackie virus can kill cancer cells in a test tube and in mice but leaves normal tissue largely unaffected. Researchers are about to start trialling a purified form of the virus, trademarked Cavatak, in Australian patients with late-stage breast cancer, melanoma and prostate cancer who have not responded to conventional treatments or refused them.

Biomedical scientist Kathryn Skelding, of the University of Newcastle, said if the treatment proved successful, the hope was that it may eventually replace chemotherapy and radiation, which both have debilitating side effects for patients, including nausea and hair loss.

Ms Skelding, a PhD student, has been studying the effect of the virus on breast cancer in mice with help from a National Breast Cancer Foundation grant. "What I've been able to show is that this virus ... is able to cause a reduction in tumour volumes in a mouse model of breast cancer as well as eliminate secondary tumours," she said.

Her supervisor, Darren Shafren, who has been studying the virus since the mid-1990s, said two molecules that it used to infect cells were expressed in higher numbers on malignant cancer cells than on normal tissue. Associate Professor Shafren stressed much more research was necessary before scientists could say whether Cavatak offered significant hope to cancer patients. He said that initially Cavatak may be used in combination with conventional therapies if early human trials showed promise. Two hospital trials about to begin are designed mainly to assess the safety of the potential new therapy. The trials will be funded by publicly listed company Viralytics Ltd



Women who consume low-fat milk and yoghurt may find it harder to become pregnant, a new study has found. A team at Harvard School of Public Health found that women who eat a lot of low-fat dairy foods were 85 per cent more likely to suffer from a failure to ovulate. Women who had a least one serving a day of a high-fat dairy food were 27 per cent less likely to suffer from this form of infertility than were those who consumed high-fat dairy food only once a week.

The finding suggests that the obsession with low-fat foods, driven by nutritionists trying to protect against heart disease and by consumers trying to lose weight, may have a downside. Anovulatory infertility - the type studied here - is just one of a variety of ways in which infertility can be caused. In the population studied, it was responsible for one in eight cases of a failure to conceive. The data comes from the Nurses' Study, a long-running research project in the US that draws comparisons between diet and lifestyle and medical history.

A team led by Jorge Chavarro of the Department of Nutrition at Harvard and colleagues used a subset of more than 18,000 married nurses from the study who had either become pregnant or attempted to do so during an eight-year period in the 1990s. Their success, or lack of it, was compared with their dietary habits, which had been recorded several years earlier. There were 3,430 cases of infertility, of which 438 were identified as having been caused by a failure to ovulate. By comparing the diet of these women with that of women who conceived successfully, the team were able to draw their conclusions.

The scientists, whose work is published in Human Reproduction, say that the total intake of dairy foods shows no link with anovulatory infertility. But when high-fat and low-fat dairy foods were considered separately, a difference emerged. Women consuming at least five portions week of low-fat foods had a higher than average risk of being infertile. If women ate two or more servings of low-fat dairy foods a day, they increased their risk of ovulation-related infertility by more than four fifths (85 per cent) compared with women who ate less than one serving of low-fat dairy food a week. And if women ate at least one serving of high-fat dairy food a day, they reduced their risk by more than a quarter (27 per cent) compared with women who consumed one or fewer high-fat dairy servings a week. High-fat foods include ice-cream and whole milk.

Dr Chavarro said that his advice to women wanting to conceive would be to change their diet. "They should consider changing low-fat dairy foods for high-fat dairy foods; for instance, by swapping skimmed milk for whole milk and eating ice-cream, not low-fat yoghurt." But he added that it was important that women did this within the constraints of maintaining their normal calorie intake and limiting saturated fats. He said that once they are pregnant "they should probably switch back to low-fat dairy foods as it is easier to limit intake of saturated fat by consuming low-fat dairy foods".

Just why low-fat dairy foods should have this effect is not yet clear. High-fat dairy products have a higher concentration of the female sex hormone oestrogen than do their low-fat counterparts. Alternatively, greater insulin sensitivity among high-fat dairy consumers may improve ovulatory function. "Given the scarcity of studies in this area, it is important that our studies are confirmed or refuted," the team said. Dr Chavarro added: "Clarifying the role of dairy foods intake on fertility is particularly important since the current dietary guidelines for Americans recommend that adults consume three or more daily servings of low-fat milk or equivalent dairy products. "This is a strategy that may well be deleterious for women planning to become pregnant as it would give them an 85 per cent higher risk of anovulatory infertility."


Weight-loss pill maker slams ad ban

But you can buy all sorts of stuff that DOESN'T work??

The maker of the weight-loss pill Xenical has slammed an official U-turn that once again bans advertisements for the controversial drug, describing it as inconsistent with the free rein given to "hocus pocus" alternative products. The federal Government's National Drugs and Poisons Schedule Committee last week announced it would overturn a previous decision to allow Xenical, marketed by Roche Products, to be advertised direct to the public. The advertising rules were relaxed after Xenical was delisted as a prescription-only drug last year and made available over the pharmacy counter.

The committee last week decided to keep Xenical as a non-prescription drug, but said it had heeded warnings that direct-to-consumer advertising "increased pressure on pharmacists" to sell it. It said the committee "decided that, on balance, there was insufficient public health benefit associated with allowing direct-to-consumer advertising" of Xenical, also known by its chemical name orlistat.

Xenical is only intended for use in a relatively small group of obese patients with a body mass index above 27. But last year consumer group Choice raised concerns after advertisements for Xenical were screened during the TV program Australian Idol. Choice sent a 19-year-old girl with a healthy weight to 30 pharmacies, and found 24 were prepared to sell her the drug contrary to the guidelines.

Roche Products managing director Fred Nadjarian said the reimposition of the advertising ban was inconsistent as "products with dubious ingredients largely based on green tea extract, eye of newt, wing of bat and guinea pig tail can be (advertised)". "The inconsistency in the NDPSC process has left us with no confidence in their decision-making abilities and we are now at a loss as to how to make Xenical available to those who need it," he said.

Choice spokeswoman Indira Naidoo welcomed the advertising ban, but regretted the committee did not also reimpose the requirement for a doctor's prescription for Xenical. "We hope that the actions of the committee will put added pressure on pharmacists to make sure they are providing the drug appropriately," she said.



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.