ISLAMABAD – A simple eye test may help combat Alzheimer’s disease by detecting the sufferers well in advance of the destruction caused by the killer brain disease, scientists claim.
Alzheimer’s is an incurable condition and experts believe the key to tackling it - and stopping it - lies in early detection. Research led by Lancaster University - in partnership with Royal Preston Hospital, Lancashire Teaching Hospitals NHS foundation trust - has shown that people with Alzheimer`s have difficulty with one particular type of eye tracking test, the Daily Express reported.
As part of the team’s study, 18 patients with Alzheimer’s, 25 patients with Parkinson’s, 17 healthy young people and 18 healthy older people were asked to follow the movements of light on a computer.
But in some instances they were asked to look away from the light. Detailed eye-tracking measurements taken from the group showed stark contrasts in results.
Alzheimer’s patients made errors when they were asked to look away from the light and were unable to correct those errors. This was despite them being able to respond perfectly normally when asked to look towards the light.
These errors were 10 times more frequent in the Alzheimer’s patients compared with the control groups.
The researchers, whose study is published in the Journal of the American Ageing Association, also measured memory function among Alzheimer’s patients who found the test difficult. This revealed a clear correlation with lower memory function.
Dr Trevor Crawford, of the department of Psychology and the Centre for Ageing Research at Lancaster University, said these new results were potentially very exciting as they demonstrated, for the first time, a connection with the memory impairment that is so often the first noticeable symptom in Alzheimer`s disease.
“The diagnosis of Alzheimer`s disease is currently heavily dependent on the results of a series of lengthy neuropsychological tests,” he said.
“However, patients with a dementia often find that these tests are difficult to complete due to a lack of clear understanding and lapse in their attention or motivation.
“The light tracking test could play a vital role in diagnosis as it allows us to identify and exclude alternative explanations of the test results,” he added.
Alzheimer’s disease is a devastating disorder, which starts many years before the symptoms begin to appear.
A toxic protein in the brain called beta amyloid is a hallmark of the disease and can build up for more than a decade before any outward signs of dementia such as confusion or memory loss.
Dr Eric Karran, director of research at Alzheimer’s Research UK, said: “This study suggests eye-tracking tests could help to highlight memory problems in Alzheimer’s. While it is unlikely Alzheimer’s could be diagnosed by a single eye test, the findings could help expand the battery of tests currently needed for diagnosis
Apple peel can help stave off high BP
Eating an apple a day without removing the peel can help prevent high blood pressure. Canadian scientists have found that the fruit is more effective than other “superfoods” including green tea and blueberries as a source of antioxidants and chemical compounds called flavonoids that combat the potentially life-threatening condition.
In a study, researchers from Nova Scotia Agricultural College tested the peel and the fleshy fruit of apples separately. The peel was found to be up to six times more effective in inhibiting an enzyme called ACE, which is known to cause hypertension and high blood pressure, according to the team`s results in the journal Food Chemistry. “Apples are one of the most popular and frequently consumed fruits in the world,” the Daily Express quoted the researchers as stating.
“Apple peel is a rich source of flavonoids which provide numerous health benefits - apple peel flavonoids inhibited the enzyme ACE,” they added.
New biosensor detects glucose in saliva and tears for diabetes testing
Painful pinpricks for diabetes testing could soon be a thing of past as researchers have created a new type of biosensor that can detect minute concentrations of glucose in saliva, tears and urine.
It might be manufactured at low cost because it does not require many processing steps to produce.
“It’s an inherently non-invasive way to estimate glucose content in the body,” said Jonathan Claussen, a former Purdue University doctoral student and now a research scientist at the U.S. Naval Research Laboratory.
“Because it can detect glucose in the saliva and tears, it’s a platform that might eventually help to eliminate or reduce the frequency of using pinpricks for diabetes testing.
We are proving its functionality,” Claussen noted.
Claussen and Purdue doctoral student Anurag Kumar led the project, working with Timothy Fisher, a Purdue professor of mechanical engineering; D. Marshall Porterfield, a professor of agricultural and biological engineering; and other researchers at the university`s Birck Nanotechnology Center.
“Most sensors typically measure glucose in blood. Many in the literature aren`t able to detect glucose in tears and the saliva. What`s unique is that we can sense in all four different human serums: the saliva, blood, tears and urine. And that hasn`t been shown before,” Claussen said.
The sensor has three main parts: layers of nanosheets resembling tiny rose petals made of a material called graphene, which is a single-atom-thick film of carbon; platinum nanoparticles; and the enzyme glucose oxidase.
Each petal contains a few layers of stacked graphene. The edges of the petals have dangling, incomplete chemical bonds, defects where platinum nanoparticles can attach. Electrodes are formed by combining the nanosheet petals and platinum nanoparticles. Then the glucose oxidase attaches to the platinum nanoparticles. The enzyme converts glucose to peroxide, which generates a signal on the electrode.
In addition to diabetes testing, the technology might be used for sensing a variety of chemical compounds to test for other medical conditions.
“Because we used the enzyme glucose oxidase in this work, it`s geared for diabetes. But we could just swap out that enzyme with, for example, glutemate oxidase, to measure the neurotransmitter glutamate to test for Parkinson`s and Alzheimer’s, or ethanol oxidase to monitor alcohol levels for a breathalyzer. It’s very versatile, fast and portable,” Claussen said.
The technology is able to detect glucose in concentrations as low as 0.3 micromolar, far more sensitive than other electrochemical biosensors based on graphene or graphite, carbon nanotubes and metallic nanoparticles, Claussen said
“These are the first findings to report such a low sensing limit and, at the same time, such a wide sensing range,” he said.
Findings are detailed in a research paper being published this week in the journal Advanced Functional Materials.