Health, Medical, Research, Science, United States

Eye tests may detect early onset of Alzheimer’s…

AMYLOID PLAQUES

Two new eye tests in America are being trialled that one day may help doctors to detect the very early stages of Alzheimer’s disease.

Newly released research has revealed that non-invasive retinal testing is now being trialled by scientists in the U.S. that could help flag up the condition by alerting clinicians to the presence of amyloid plaque deposits, a known biological marker of the disease.

Early stage testing could mean that patients are diagnosed or registered as high-risk up to twenty years before noticeable symptoms begin, helping patients get treatment before memory loss develops.

Scientists generally accept that amyloid plaques (a type of residual protein deposit) in the brain are a key marker of the disease.

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Neurologists have believed for a long time that there is a correlation between the amounts of amyloid in the eye and residual protein deposits in the brain. The argument for this correlating factor is a strong one because the retina is formed from the same tissue as the brain when a foetus is developing in the womb.

To confirm this theory, two tests have been developed and trials are currently underway. The tests are known as the Retinal Amyloid Index (by NeuroVision) and the Sapphire II (by Cognoptix).

Ocular based examinations through the years have been used to detect and diagnose Alzheimer’s at any early stage through methods such as optic nerve cupping, pupillary response to tropicamide dilation and ocular muscle movement. However, all have failed to withstand the test of time in terms of sensitivity and specificity.

Professor Keith Black is chairman of the Department of Neurosurgery at Cedars-Sinai Medical Centre in Los Angeles, and co-founder of NeuroVision. He says that if people are going to get Alzheimer’s they begin to develop the hallmarks, such as amyloid deposits, in their 50s.

Professor Black said:

… The key for having an effective treatment for AD is early detection. You want to prevent those brain cells from being killed or dying in the first place.

The Sapphire II test works by measuring the amount of photons (i.e. light particles) captured when scanning the eyes. The amount of photons captured directly correlates with the amount of amyloid in the eye.

Experts state that the Sapphire II is currently in phase one of two in clinical feasibility trials, and that phase three is expected to begin in 2014.

Approximately 800,000 people in Britain suffer from Alzheimer’s and other forms of dementia. The number of cases is predicted to double within a generation.

There is no cure for Alzheimer’s disease and existing drugs can only alleviate symptoms. The condition is diagnosed by memory tests and, in some cases, through brain scans.

Presently, the disease can only be confirmed by a post-mortem examination, which reveals the presence of harmful amyloid plaques in the brain.

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Britain, Government, History, Intelligence, Military, United States

RAF Cold War missions over the former Soviet Union…

COVERT FLIGHTS

The RAF flew covert spying missions over the former Soviet Union at the height of the Cold War.

After decades of secrecy, CIA documents show British pilots were involved in the U-2 flights in 1959 and 1960.

These missions gathered vital intelligence which was regarded by the American intelligence services as being worth ‘a million dollars’.

Until now the Ministry of Defence has neither confirmed nor denied the participation of the RAF in the controversial missions, a position it will no longer be able to maintain.

The first U-2 flights over the Soviet Union started in July 1956, but despite the valuable information gathered, President Dwight Eisenhower was concerned about the ramifications of such a flagrant breach of Russian air space if they were discovered.

Unfortunately for the Americans, even though the high-tech U-2s flew at more than 70,000ft, the Russians were still able to track the planes.

The Soviets sent a strongly worded protest to Eisenhower, who developed second thoughts about the missions and suspended such flights in December 1956.

But the CIA was extremely keen for the spying missions to continue and looked for ways, in the words of one CIA document, ‘to increase the possibility of plausible denial’.

The solution was to use British pilots for the sensitive missions. During the spring of 1957, negotiations took place between the CIA and the chief of MI6, Sir Dick White, who saw the immediate benefits for Britain.

By the summer of 1958, Prime Minister Harold Macmillan had given his authorisation, and four RAF officers, Squadron Leader Christopher Walker and Flight Lieutenants Michael Bradley, John MacArthur and David Dowling – all of whom were in their twenties and single – were sent to train on flying the U-2s in Texas.

Flying the U-2s, however, was not without risk, and on July 8, 1958, Walker was killed when his plane crashed. The cause was never definitively established, but it is believed the aircraft disintegrated at high altitude.

He was immediately replaced by Wing Commander Robert Robinson. By 1959 all four men had finished their operational conversion to the U-2 and were sent to a secret air base in Turkey. From there they launched their flights over the Soviet Union and the Middle East.

In order to emphasise American denials of the operation, the U-2 planes were formally transferred on paper to the British Government. Eisenhower wrote to Macmillan, stating: ‘British missions are carried out on your authority and are your responsibility.’

And the flights remained a secret in Britain, too. The pilots were no longer paid by the RAF, but by MI6, and the public was told the airmen were engaging in ‘high-altitude weather-sampling missions’.

The first mission was flown by Wing Commander Robinson on December 6, 1959, over the Kapustin Yar missile test range and a squadron of long-range bombers in the Ukraine.

The missions proved to be hugely successful and proved the Soviets did not have as many bombers as they claimed – a vital piece of intelligence at the height of the Cold War. The head of the CIA referred to photographs taken by Wing Commander Robinson as being worth ‘a million dollars’.

The second British U-2 mission over the Soviet Union was flow by Flight Lieutenant John MacArthur the following month. Although his brief was to look for missile sites around the Aral Sea, he ended up uncovering a new type of Soviet bomber called the Tupolev Tu-22 at Kazan.

The Americans later resumed their involvement in the U-2 missions, but this came to an abrupt end in the wake of the Soviets shooting down and imprisoning US pilot Gary Powers in May 1960. The British ordered the RAF officers to leave Turkey immediately.

The following year, all four British RAF pilots received the Air Force Cross, although their citations in the London Gazette did not mention exactly why. After more than half a century, the truth has now been revealed.

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Health, Medical, Research, Science

British scientists unlock the secret DNA genetics of 30 cancers…

MUTATIONAL SIGNATURES

Scientists in the UK have achieved a ‘profound’ and major breakthrough in the fight against cancer that could lead to new treatments and possibly even its prevention.

Despite significant advances, very little is known about what triggers cancer, which kills around half the 325,000 Britons diagnosed with it each year.

But British scientists believe they have unlocked the DNA secrets of 30 of the most common forms of the disease. This will now bring us closer in understanding their causes.

In the biggest analysis yet of its kind, the researchers compared DNA from more than 7,000 cancer patients around the world. The cases included the most common forms, including breast, bowel, lung and prostate, which account for more than half of those diagnosed in Britain.

Cancer is caused by mutations in DNA. These mutations are caused by such things as tobacco in the case of lung or throat cancer, and excess ultraviolet light in the case of skin cancer. Researchers looked for patterns in the genetic code of the tumours made by these mutations.

Analysis of the 7,000 DNA samples revealed 21 patterns that between them were responsible for 30 cancers. Working out which food, drink, habit or other external factor causes them could lead to new ways of preventing the disease.

Knowing more about the genetics of cancer should also speed the search for new treatments – and some existing drugs might also work better in those whose tumours are caused by particular patterns.

Certain patterns in the tumour DNA were expected, such as the one caused by smoking; but others were surprising, including one believed to be caused by a protein that helps us fight infections.

Some of the patterns were only found in one type of cancer, while others, such as the marks left by ageing, were found in many different tumours.

Although further research may reveal more patterns – or ‘mutational signatures’ – the scientists, from the Wellcome Trust Sanger Institute near Cambridge, believe they have found most of them.

Professor Mike Stratton, the lead researcher, said:

… This compendium of mutational signatures and consequent insights into the mutational processes underlying them has profound implications for the understanding of cancer development, with potential applications in disease prevention and treatment.

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