Wednesday, May 23, 2007

Prostate test

A simple blood test for aggressive forms of prostate cancer has moved a step closer with the discovery that a genetic marker is linked to the most serious forms of the disease. The marker, called 8q24, lies on chromosome 8 and was originally discovered by deCODE, a genetics company that made a deal with the Government of Iceland to use health data from the closely knit Icelandic population to search for genes that cause common diseases.

Scientists from Northwestern University, in Chicago, reported yesterday at a meeting of the American Urological Association in Anaheim, California, that men who carry this marker have more aggressive tumours and are more likely to have had a close relative who will suffer prostate cancer.

Earlier work by deCODE and Northwestern has shown that about 15 per cent of Americans of European origin carry the marker, and 30 per cent of African-Americans. This work also showed that carrying the marker increased the risk of getting prostate cancer by 60 per cent.

The new research is important because tests for prostate cancer are poor. The PSA (Prostate Specific Antigen) test has its uses, but cannot reliably differentiate prostate cancers that need treatment from those that can simply be monitored.

Many men may be unaware they have prostate cancer and die of something else. Slow-developing cancer are best left, with treatments focused on more aggressive cancers. So a test that could reliably identify dangerous cancers at an early stage would be invaluable. The Northwestern study of 550 prostate cancer patients showed that those who carry the 8q24 marker have a 40 per cent chance of having a close family member with prostate cancer, whereas those who do not carry the marker have a 20 per cent chance. "These findings will help us to understand the mechanisms underlying prostate cancer," said Brian Helfand, assistant research professor of urology at Northwestern's Feinberg School of Medicine and a co-principal investigator of the study. "They hold great promise for the development of new treatments and prevention. "We found that the carriers of these 8q24 markers had more aggressive tumors," he said. Patients who were carriers had cancers that were more likely to spread into the lymph nodes and were more difficult to remove surgically.

The patients in the study had been treated by Professor William Catalona. Professor Helfand said: "We have the best-detailed prostate cancer population to perform this study because Dr Catalona has a rich database and follow-up on all of his patients."

Since the discovery of the 8q24 marker was published last year by deCODE, Professor Catalona, and two other research groups, the research has been confirmed by a number of other groups. This is the first time that a genetic mutation associated with prostate cancer has been found in a large segment of the population.


A drink a day may slow dementia

The findings below are fairly weak but add to the now considerable body of evidence that alcohol is one of the most widely useful drugs we have

In older people with mild cognitive impairment, having a drink now and then - up to an average of one drink of alcohol each day - may delay progression to dementia, new Italian research suggests. "While many studies have assessed alcohol consumption and cognitive function in the elderly, this is the first study to look at how alcohol consumption affects the rate of progression of mild cognitive impairment to dementia," study authors Dr Vincenzo Solfrizzi and Dr Francesco Panza, from the University of Bari in Italy, said.

In the study, reported in the medical journal Neurology, the researchers assessed the occurrence of mild cognitive impairment in 1445 subjects and the progression to dementia in 121 patients with mild cognitive impairment. The participants were between 65 and 84 years of age at the start of the study, and they were followed for 3.5 years. Alcohol use was assessed starting the year before the survey.

Drinking was not associated the development of mild cognitive impairment, according to the report. However, once mild impairment occurred, subjects who had up to one drink per day of alcohol had an 85 per cent reduced risk of dementia compared with those who abstained. The benefit was seen with both alcohol in general and with wine in particular.

Having more than one drink a day, however, offered no protection against dementia compared with abstaining, the report indicates. "The mechanism responsible for why low alcohol consumption appears to protect against the progression to dementia isn't known. However, it is possible that the arrangement of blood vessels in the brain may play a role," Dr Solfrizzi and Dr Panza conclude.



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.


No comments: