Category Archives: Science

Britain, Health, Medical, Research, Science

A simple surgical operation to cure high blood pressure…

CLINICAL TRIALS START FOR TREATING HYPERTENSION

British scientists believe they could cure millions of patients with hard-to-treat high blood pressure and hypertension.

A simple operation would involve removing a small cluster of nerves in the throat linked to blood pressure regulation.

Researchers from Bristol University are extremely hopeful the measures could help some 2.5 million individuals with hypertension that cannot be controlled by medication.

While scientists have already started a clinical trial on 20 people with high blood pressure – following successful laboratory tests on rats – if the trials prove to be successful and is given the go-ahead, the surgical procedure could be available within three years as a ‘relatively simple’ day treatment for adults. The novel approach successfully ‘cured’ the condition in laboratory rats.

The carotid body is one of the body’s smallest organs but acts as a sensor that detects changes in gas levels in the blood. Sometimes, however, it can become overactive.

The carotid body is one of the body’s smallest organs but acts as a sensor that detects changes in gas levels in the blood. Sometimes, however, it can become overactive.

Known as the silent killer, high blood pressure or hypertension affects a third of adults and significantly raises the odds of heart attacks, strokes and other potentially fatal conditions if left untreated.

At the moment, there is no effective remedy for individuals who do not respond to conventional drug therapies.

But scientists at Bristol’s School of Physiology and Pharmacology identified a key organ in the development of high blood pressure – the carotid body.

It consists of a tiny cluster of nerve cells that sit on the side of the two branches of the carotid artery in the neck, each the size of a grain of rice.

Despite being one of the body’s smallest organs, it has the highest blood flow of them all – reflecting its importance as an early warning device for the brain if there is any change to oxygen and carbon dioxide levels in the blood.

In some cases, it is thought the carotid body becomes overactive and sends a message to the brain to keep blood pressure high. Scientists involved in removing the organs in rats with hypertension found that blood pressure fell and remained low.

The study, which was funded by the British Heart Foundation, and first published in the journal Nature Communications, said the animals suffered no adverse side-effects either.

In human trials, only one carotid body would be removed in order to reduce blood pressure while maintaining the organ’s vital regulatory function.

Professor Julian Paton who is the lead researcher on the study, said:

… We know that these tiny organs behaved differently in conditions of hypertension, but had absolutely no idea that they contributed so massively to the generation of high blood pressure; this is really most exciting.

… It certainly has the potential to be a very novel interventional approach to drug-resistant hypertension (high blood pressure).

An estimated 16 million British adults have high blood pressure; a third of whom may be unaware they have the condition.

Patients are often at first advised to alter their lifestyle by taking more exercise, stopping smoking, cutting down on drinking and limiting the salt and fat in their diet.

GPs can also prescribe medication – often a combination of pills – but many patients skip doses because of the side-effects caused by most treatments. Up to 15 per cent of patients – 2.5 million people – also struggle to control their condition using drugs.

Professor Jeremy Pearson, associate medical director at the British Heart Foundation, said:

… This potential new treatment has real promise to help this hard-to-treat group of patients … Many patients can control their blood pressure adequately by lifestyle change and medication so they would not be offered this kind of treatment.

… It is therefore unlikely this treatment will ever be tested as an alternative to standard medication – only as an extra procedure when current drug treatment fails.

A consultant cardiologist at Sheffield Teaching Hospital referred to the breakthrough as an ‘exciting and innovative approach’ and added that current treatments for high blood pressure have serious drawbacks, such as no-one likes taking multiple tablets and that medics are often guilty of not explaining properly why treatment is needed and what benefits might be expected.

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Arts, History, Philosophy, Science

Quantum Leaps: Robert Hooke…

1635 – 1703

Perhaps one of the most ‘underrated’ scientists of the seventeenth century, Robert Hooke, an Englishman, experimented and made advances in a wide range of scientific areas. Yet because of this breadth of coverage, he seldom developed any of his concepts to their fullest extent. This explains why he rarely gained credit for them. Indeed, it is arguable that his role as a provider and facilitator to others is his most important legacy.

Boyle’s Assistant – The most obvious example of his contribution to others was the work he undertook with Robert Boyle at Oxford, where they met in 1656. Boyle, as the aristocrat, was clearly the dominant partner in the relationship, in social terms at least. Hooke, as his assistant, acted on Boyle’s instructions, yet many of his creations were worthy inventions in their own right. The most obvious example is the air pump that he devised in 1659, the most efficient vacuum creator of its time. It enabled Boyle to go on to make many of his discoveries.

Provider of Ideas – Moreover, Boyle was responsible, albeit indirectly, for keeping Hooke in his position as jack of all sciences, master of none. The aristocrat had been influential in having Hooke elevated to the position of Curator of Experiments for the Royal Society in 1662. While the prestige of the role pleased Hooke, the job requirement of showing ‘three or four considerable experiments’ to the Society at each of its weekly meetings was almost certainly the factor that ensured Hooke would never have the time to develop any of his findings fully.

A Source of Ideas – Another scientist to whom Hooke felt he had provided source material was the Dutch physicist Christian Huygens. Huygens is credited with creating the influential wave theory of light, which he published in 1690. Yet as early as 1672, Hooke had explained his discovery of diffraction (the bending of light rays) by suggesting that light might behave in a wave-like fashion.

In 1662, Robert Hooke became the first Curator of Experiments to the Royal Society. In 1670 he discovered the ‘law of elasticity’.

In 1662, Robert Hooke became the first Curator of Experiments to the Royal Society. In 1670 he discovered the ‘law of elasticity’.

Isaac Newton vehemently argued against Hooke’s theory of light, beginning a bitter feud which would continue for the rest of Hooke’s life. Hooke also claimed to have discovered one of the most important theories credited to Newton, arguing that the latter had plagiarised his ideas from correspondence between the two during 1680. Certainly, Hooke’s letters suggested some notion of universal gravitation and hinted at an understanding of what later became Newton’s law of gravity. In spite of this, though, it is unquestionable that Newton’s mathematical calculations and endeavours in proving the law give him a much stronger claim.

Robert Hooke’s countless experiments did, however, result in some other discoveries solely credited to him. He was, for example, the first to describe the universal law that all matter will expand upon heating. He is credited with the law of elasticity, discovered in 1670. Also known as Hooke’s Law, it states that the strain, or change in size, placed upon a solid – when stretched – is directly proportional to the stress, or force, applied to it. Hooke was also the first person to use the word ‘cell’ in the scientific sense understood by us today, after observing the properties of cork under one of the powerful microscopes that he had developed. This word was used in his 1665 work Micrographia or Small Drawings, which also included many other advances such as Hooke’s theory of combustion, as well as other discoveries of the microscope. These included crystalline structure of snow, and studies of fossils which led to the proposition that they were the remains of once living creatures. He suggested that whole species had lived and died out long before man, centuries before Charles Darwin came to the same conclusion.

Hooke also made discoveries in astronomy, locating Jupiter’s Great Red Spot, and proposed that the huge planet rotated on its axis.

Further accreditations – Hooke’s inventions were greatly influential. He either invented or significantly improved the reflecting telescope, compound microscope, dial barometer, anemometer, hygrometer, balance spring (for use in watches), quadrant, universal joint and iris diaphragm (later used in cameras). He also showed impressive vision, foreseeing the development of the steam engine and the telegraph system.

Beyond this he was an accomplished architect who designed parts of London following the great fire of 1666.

Inset – In 1662, Robert Hooke became the first Curator of Experiments to the Royal Society. In 1670 he discovered the ‘law of elasticity’.

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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.

This site incorporates a science and biology page. Click the image icon to view it.

This site incorporates a science and biology page. Click the image icon to view it.

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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