Fish Really Is 'Brain Food': Vitamin D May Lessen Age-related Cognitive Decline

Eating fish – long considered ‘brain food’ – may really be good for the old grey matter, as is a healthy dose of sunshine, new research suggests.University of Manchester scientists in collaboration with colleagues from other European centres have shown that higher levels of vitamin D – primarily synthesised in the skin following sun exposure but also found in certain foods such as oily fish – are associated with improved cognitive function in middle-aged and older men.

The study, published in the Journal of Neurology, Neurosurgery and Psychiatry, compared the cognitive performance of more than 3,000 men aged 40 to 79 years at eight test centres across Europe.

The researchers found that men with higher levels of vitamin D performed consistently better in a simple and sensitive neuropsychological test that assesses an individual’s attention and speed of information processing.

“Previous studies exploring the relationship between vitamin D and cognitive performance in adults have produced inconsistent findings but we observed a significant, independent association between a slower information processing speed and lower levels of vitamin D,” said lead author Dr David Lee, in Manchester’s School of Translational Medicine.

“The main strengths of our study are that it is based on a large population sample and took into account potential interfering factors, such as depression, season and levels of physical activity.

“Interestingly, the association between increased vitamin D and faster information processing was more significant in men aged over 60 years, although the biological reasons for this remain unclear.”

“The positive effects vitamin D appears to have on the brain need to be explored further but certainly raise questions about its potential benefit for minimising ageing-related declines in cognitive performance.”

Face Protection Effective In Preventing The Spread Of Influenza, Study Suggests

A new article in the journal Risk Analysis assessed various ways in which aerosol transmission of the flu, a central mode of diffusion which involves breathing droplets in the air, can be reduced. Results show that face protection is a key infection control measure for influenza and can thus affect how people should try to protect themselves from the swine flu.Lawrence M. Wein, Ph.D., and Michael P. Atkinson of Stanford University constructed a mathematical model of aerosol transmission of the flu to explore infection control measures in the home.

Their model predicted that the use of face protection including N95 respirators (these fit tight around the face and are often worn by construction workers) and surgical masks (these fit looser around the face and are often worn by dental hygienists) are effective in preventing the flu. The filters in surgical masks keep out 98 percent of the virus. Also, only 30 percent of the benefits of the respirators and masks are achieved if they are used only after an infected person develops symptoms.

"Our research aids in the understanding of the efficacy of infection control measures for influenza, and provides a framework about the routes of transmission," the authors conclude.

This timely article has the potential to impact current efforts and recommendations to control the so-called swine flu by international, national and local governments in perspective.

This study is published in the journal Risk Analysis. Media wishing to receive a PDF of this article may contact .net.

Bad Breath? New Pocket-sized Breath Test Developed

A quick breath check in the palm of your hand can never give accurate results. Whether you're about to lean in for a smooch or start a job interview, you're better off asking a trusted friend if your breath is sweet. But what if a friend isn't around when you need one?

Tel Aviv University researchers have come up with the ultimate solution — a pocket-size breath test which lets you know if malodorous bacteria are brewing in your mouth. A blue result suggests you need a toothbrush. But if it's clear, you're "okay to kiss."

Until now, scientists believed that only one population of bacteria (the Gram-negative ones) break down the proteins in the mouth and produce foul odor. But Prof. Mel Rosenberg and Dr. Nir Sterer of TAU's Sackler Faculty of Medicine recently discovered that the other population of bacteria (the Gram-positive ones) are bad breath's bacterial partner. These bacteria appear to help the Gram-negative ones by producing enzymes that chop sugary bits off the proteins that make them more easily degraded. This enzymatic activity, present in saliva, serves as the basis for the new "OkayToKiss" test.

Prof. Rosenberg, international authority on the diagnosis and treatment of bad breath, who co-developed the kit with Dr. Sterer, published their findings this past March in the Journal of Breath Research, of which Prof. Rosenberg is editor-in-chief. An earlier invention of Prof. Rosenberg led to the development of two-phase mouthwashes that have become a hit in the UK, Israel and elsewhere.

From the Lab to Your Pocket

The patent-pending invention is the result of ongoing research in Prof. Rosenberg's laboratory.

"All a user has to do is dab a little bit of saliva onto a small window of the OkayToKiss kit," explains Prof. Rosenberg: "OkayToKiss will turn blue if a person has enzymes in the mouth produced by the Gram-positive bacteria. The presence of these enzymes means that the mouth is busily producing bacteria that foster nasty breath," he explains.

Apart from its social uses, the test can be used as an indicator of a person's oral hygiene, encouraging better health habits, such as flossing, brushing the teeth, or scheduling that long-delayed visit to the dentist.

OkayToKiss could be ready in about a year for commercial distribution, probably in the size of a pack of chewing gum, to fit in a pocket or purse. It is disposable and could be distributed alongside breath-controlling products.

Science Behind the Smells

"For about 7 years now, we've suspected that there's another kind of bacteria at work in the mouth which causes bad breath," says Prof. Rosenberg. "Now, we are able to grow these bacteria from saliva in an artificial biofilm, showing that there are two distinct populations at work."

In the biofilm — the basis of the new breath test — the color difference between the Gram-positive and Gram-negative bacteria is remarkable. In the top layer of the biofilm, the bacterium take the glycoproteins in the saliva and chop off sugar residues to produce volatile proteins. On the lower layer in the biofilm, which could roughly be compared to one's tongue or inner lining of the mouth, reside the known and established Gram-negative bacteria.

Biomarkers, like the ones used by Prof. Rosenberg's new invention, are the basis of popular diagnostic kits today, like home pregnancy tests or glucose monitors used by diabetics. Checking the sweetness of one's breath may seem frivolous, but millions worry about it on a continual basis. Prof. Rosenberg's continued research into biomarkers in saliva is very promising for diagnosing other more serious disorders, including indicators for lung cancer, asthma and ulcers.

Prof. Rosenberg has summarized his twenty years of his research and experience on bad breath problems in a new book, Save Your Breath, due out in two months. This new work is a collaborative effort with Dr. Nir Sterer and Dr. Miriam Shaharbany of the Sackler Medical Faculty.