Tuesday, February 10, 2009

Smoking cannabis 'increases the risk of aggressive testicular cancer'

This is just another rubbish retrospective self-report study. There also appears to be an element of data dredging. Given the frequency of marijuana use, there would be an epidemic of rotted balls if it were true. What the study really shows is that men who get testicular cancer tend to blame their own behaviour for it and exaggerate their past risky behaviour

Smoking cannabis puts men at increased risk of the most aggressive type of testicular cancer, say scientists. Men who smoked at least once a week or who had smoked since adolescence were twice as likely to develop the disease as those who didn't use the drug, the U.S. researchers found. Dr Stephen Schwartz, who led the study, said more research was needed to confirm the link - and to show why the drug puts men at risk. `Our study is the first inkling that marijuana use may be associated with testicular cancer, and we still have a lot of unanswered questions,' he said.

`What young men should know is that first, we know very little about the long-term health consequences of marijuana smoking, especially heavy marijuana smoking - and second, our study provides some evidence that testicular cancer could be one adverse consequence. `So in the absence of more certain information, a decision to smoke marijuana recreationally means that one is taking a chance on one's future health.'

Some 2,100 men are diagnosed with testicular cancer in Britain each year. Most are cured - and 98 per cent of those diagnosed are still alive after ten years.

The study, at the Fred Hutchinson Cancer Research Centre in Seattle, Washington, looked at all types of testicular cancer. Dr Schwartz interviewed 369 men aged 18 to 44 who had been diagnosed with the disease about their cannabis use. They compared the results with interviews from 979 randomly chosen men of the same age. Men who smoked cannabis were 70 per cent more likely to be diagnosed with the disease. Men who smoked at least once a week or who had smoked since adolescence were twice as likely to have testicular cancer, they report in the journal Cancer.

The link seemed strongest with a fast-growing malignancy called nonseminoma, which tends to strike early, between the ages of 20 and 35, and accounts for around 40 per cent of all testicular cancer cases.


Revolutionary drug that can stop Alzheimer's and restore memory

But only in freak mice so far

A revolutionary drug that could stop Alzheimer's disease in its tracks and restore lost memory is being tested by scientists. The drug - a protein naturally produced by the body - can reverse memory loss in brains ravaged by the disease and stop cells from dying. Although existing pills can delay the progress of symptoms, none are capable of repairing the damage to the brain.

With 500 new cases of the disease diagnosed every day as people live longer, and a global epidemic predicted by 2050, there is a desperate need for new treatments. The research, carried out at the University of California in the US, centred on a protein called brain-derived neurotrophic factor, or BDNF, which is produced in the brain. BDNF is thought to play a key role in learning and memory, and levels drop in Alzheimer's patients.

When mice genetically-engineered to develop an Alzheimer's-like disease were injected with the gene that makes the protein, memory and learning improved, suggesting brain tissue destroyed by the disease was actually repaired. Tests on rats and monkeys showed that injections of BDNF or of its gene stopped cell death and halted memory loss. The benefits extended to the hippocampus, the brain's memory hub and one of the first regions to suffer damage in Alzheimer's disease, the journal Nature Medicine reports.

Researcher Dr Mark Tuszynski said: 'The effects of BDNF were potent. 'When we administered BDNF to the memory circuits in the brain, we directly stimulated their activity and prevent cell death from the underlying disease.' Several years ago, Dr Tuszynski showed that another naturally-occurring protein, nerve growth factor, or NGF, could treat Alzheimer's in mice. He then started treating patients, injecting pieces of skin genetically modified to make NGF deep into their brains. The trials are ongoing but preliminary results suggested that memory loss may have been slowed.

Dr Tuszynski believes the new drug holds even more potential and is also safe to be tested on people. He said: 'BDNF treatment can potentially provide long-lasting protection by slowing or even stopping disease progression in the regions that receive treatment.' He added that the drug appeared to work despite not tackling amyloid, a sticky protein that clogs the brain in Alzheimer's. Using BDNF with drugs that target amyloid would allow doctors to mount a two-pronged attack on the disease.

However, the research is at the very early stages, with new drugs taking around seven years to reach the market from when they are first tested on people. Neil Hunt, chief executive of the Alzheimer's Society, said: 'Many of the treatments for Alzheimer's disease that are currently in development concentrate on targeting amyloid production, the protein that builds up in the brain in people with Alzheimer's. 'This initial research is interesting as it seems to show that another protein, BDNF, may protect and restore memory. This research offers us insight into the way in which Alzheimer's progresses and alternative avenues of research. 'With one in three people over 65 dying with dementia it is essential that we look for as many ways of tackling the condition as possible. We look forward to further research to explore the potential benefits of BDNF in humans.'

Rebecca Wood, chief executive of the Alzheimer's Research Trust, said: 'This research is very exciting as it suggests a possible new treatment could be developed for Alzheimer's, but more research is needed before it could be available to help people with dementia. 'New treatments are desperately needed for Alzheimer's but research is seriously under-funded. 'We urgently need to fund more research now to offer hope for the future.'


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