Tuesday, April 19, 2011

Cleaning 'could be making people depressed'

This is piggybacking on the old "too clean" theory about autoimmune diseases such as asthma and diabetes. I would have thought that now to be a discredited theory but attractive theories never die of course. To repeat: Australian Aborigines usually live in extraordinarily dirty conditions but have HIGH rates of auto-immune disease and early death. Also note the "sample" size below

A growing obsession with cleanliness could be making people depressed, according to scientists. Researchers found that cleaner homes and offices are leaving lower levels of dirt and bacteria which could lead to weaker immune systems and, in turn, brain function being impaired.

Previous studies have linked clean homes to weak immune systems, while others have suggested a child's exposure to bacteria and things like animal hair could help develop a resistance to some illnesses.

The latest study, from Atlanta, suggested that weaker immune systems tend to over-react to dust and dirt in the form of inflammations or allergies which can slow the brain's production of "happy" chemicals such as serotonin and cause depression. The scientists said the rates of depression are far higher in the developed world than in poorer parts of the planet. In Britain, 10% of people claim to suffer depression, while just 1% claims the same in Nigeria, for example.

The research was conducted by exposing 27 patients to the drugs which are used to treat hepatitis C because it causes similar reactions to allergies. Dr Andrew Miller, who was behind the research, said: "We believe the immune system is causing depression. "As people develop and grow up, their immune system develops. "If they are exposed to more bacteria and parasites, they are able to better control the inflammation.

"Nowadays, people's environment is much cleaner and hygienic so our immune system never really learns how to deal with infectious agents."

The research was published in the journal Molecular Psychiatry.


New heart attack jab even more effective than statins

Rodent data only so far

A simple injection given to patients up to 12 hours after a heart attack or stroke could reduce their devastating effects by more than half, a new study claims.

British-based scientists have produced an antibody that reduces by more than 60 per cent the physical scarring of the heart and brain after an attack. The "milestone achievement" could also be used to stop the body attacking organ transplants.

Professor Wilhelm Schwaeble, who carried out the work at Leicester University, said that it could potentially be the "biggest breakthrough ever" in the treatment of two of the biggest killers in Britain.

Heart attacks and strokes are caused by blood flow being blocked by a clot or a bleed, starving parts of the body further down stream of oxygen. But most of the permanent damage is caused later – when circulation is eventually restored – and a "default of nature" which means the body's own defences attack the oxygen starved cells.

This effect, which kicks in around nine to 12 hours after the attack or stroke, causes massive inflammation and more than 80 per cent of the permanent damage. It is this that often leads to death and massive reduction in the quality of life of stroke and heart attack survivors.

Now the researchers at the University of Leicester have come up with an injection which they claim effectively stops the body attacking the oxygen starved cells. This allows them to start to oxygenate normally and the permanent damage is reduced significantly.

The research has been tested on mice and more advanced mammals and has also been shown to work on human blood in the laboratory. Human trials are expected to begin within two years.

"This is potentially the biggest breakthrough in the treatment of heart attacks and strokes ever," said Prof Wilhelm, an immunologist. "We could not believe what we saw and nor could the cardiologists. What is amazing is that the drug can be given so long after the attack. "Even the slowest ambulance journey in the world is going to get you to hospital within nine hours."

Prof Schwaeble said that the treatment could have even more of an effect than statins, the cholesterol lowering drugs taken by more than two million Britons. Around 200,000 people in Britain die from cardiovascular disease, including heart disease and stroke, every year.

The team first uncovered a key molecule in the process responsible for the immune attack. After identifying the enzyme – called Mannan Binding Lectin-Associated Serine Protease-2 (MASP-2) – they then developed a antibody to knock it out. The protein – code-named OMS646 – is so effective only two injections in the first week are needed to completely neutralise MASP-2 while the heart heals itself.

The research was published in the Proceedings of the National Academy of Sciences (PNAS).

It is anticipated that the first clinical trial will be conducted in the Leicester Biomedical Research Unit, at Glenfield Hospital, Leicester.


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