New Clues to How Flu Virus Spreads

The new research by the University of Maryland School of Public Health also found that when flu patients wear a surgical mask, the release of virus in even the smallest airborne droplets can be significantly reduced, according to FNA.

"People are generally surprised to learn that scientists don't know for sure how flu spreads," said Donald Milton, M.D., Dr.P.H., who directs the Maryland Institute for Applied Environmental Health and led the study of influenza virus aerosols published in the journal PLOS Pathogens.

"Our study provides new evidence that there is nearly nine times more influenza virus present the smallest airborne droplets in the breath exhaled from those infected with flu than in the larger droplets that would be expected to carry more virus," explains Dr. Milton. "This has important implications for how we prevent the spread of flu."

Routes of flu transmission include:

1) direct or indirect (e.g., doorknobs, keyboards) contact with an infected person,

2) contact via large droplet spray from a respiratory fluid (via coughs and sneezes), and

3) inhalation of fine airborne particles, which are generated by the release of smaller, virus-containing droplets via normal breathing and coughing. The relative importance of these modes of influenza transmission has not been well understood, but is critical in devising effective interventions to protect healthcare workers and vulnerable people, such as infants and the elderly.

The Centers for Disease Control recommends that persons with influenza wear surgical masks to prevent transmission to susceptible individuals. Yet, this recommendation has been supported so far by only one study of mask impact on the containment of large droplet spray during influenza infection.

Maryland's study is the first to provide data showing that using a surgical mask can reduce the release of even the smallest droplets containing infectious virus. For this reason, health care facilities should put surgical masks on those suspected of having influenza, and individuals with influenza can protect their families by wearing a mask.

The researchers also tested the impact of wearing a surgical mask on the virus shedding into airborne droplets. Wearing a surgical mask significantly decreased the presence of virus in airborne droplets from exhaled breath. There was a 2.8 fold reduction in the amount of virus shed into the smallest droplets, and a 3.4 fold overall reduction in virus shed in both the coarse and fine and airborne particles.

M.W

Early genetic markers of Alzheimer's risk identified

Alzheimer's brain on the left, normal brain on the right The brains of Alzheimer's patients - like the one on the left - are more shrunken than normal ones

Genetic markers that could help highlight who is at risk of developing Alzheimer's disease have been identified by US scientists.

The research in Neuron identifies mutations that affect the build-up of certain proteins in the brain.

High levels of these tau proteins increase the chance of having the disease.

UK experts said the study could help understand the changes that occur in the brains of Alzheimer's patients.

Tangles of a kind of tau called phosphorylated tau (ptau) are a hallmark of the disease.

One of the new gene variants identified by the Washington University School of Medicine team was also shown to be linked to a small increased risk of developing Alzheimer's and a greater risk of cognitive decline.

The team used genetic information from more than 1,200 people, significantly larger than previous studies in this area.

Dr Alison Goate, who led the study, said: "We anticipate that knowledge about the role of these genes in Alzheimer's disease may lead to the identification of new targets from therapies or new animal or cellular models of the disease.

Lifestyle 'plays a role'

UK experts said the study adds to the number of genetic markers that have been linked to the development of Alzheimer's disease.

Dr Doug Brown, director of research and development at the Alzheimer's Society, said: "In discovering new genes that have a link to Alzheimer's, this robust study helps scientists to better understand the way the brain changes when dementia develops.

"Research such as this may in the future help us to engineer treatments aimed at stopping such changes and therefore slowing or stopping the effects of dementia."

He added: "These new gene markers, as important as they are, are likely to be a few of many that might affect a person's risk of developing Alzheimer's.

"However, it is important to stress that lifestyle factors also play a role, and research has shown that eating a balanced diet, exercising regularly, not smoking, and getting your blood pressure and cholesterol checked regularly are key ways to reduce your risk of dementia."

Source story:BBC

R.Sawas

Excessive salt consumption dangerous

Salt, also known as sodium chloride, is made up of 40 per cent sodium and 60 per cent chloride. Found predominantly in pre-prepared foods, excessive salt consumption has been linked with high blood pressure and stomach cancer, and can exacerbate osteoporosis and asthma.

The sodium component of salt is vital for controlling the amount of water in the body, maintaining the normal pH of blood, transmitting nerve signals and helping muscular contraction. Salt is present in all foods in varying degrees, and almost all processed foods contain added salt.

Sodium, unlike all other minerals, is generally over consumed, with the dietary intake of salt in the UK being far in excess of the recommended daily requirement.

Adults are advised to consume no more than 6g salt per day (about one teaspoon). Current intake is about 9g per day - that’s 50 per cent higher than is recommended for good health. Babies and children should have less salt than adults. High salt intake in babies can be especially dangerous, as their kidneys cannot cope with large amounts.

People who have experienced heart problems or have high blood pressure should follow a low-salt diet and take advice from their health care professional. Reducing sodium has been proven to be one of the best ways of lowering high blood pressure, especially in combination with broader dietary changes.

Convenience foods, ready meals and canned foods, as well as eating out frequently, all contribute to a higher sodium intake, so read labels carefully to compare foods and opt for those lower in salt. Some labels provide both the salt and the sodium content within the product. This can be confusing, as the two are not interchangeable - 1g of salt contains 0.4g sodium

If you're checking labels, here's a guide based on 100g/ml of product:

Ways to reduce salt intake:

Use fresh or dried herbs and spices to flavour vegetables

  Avoid adding salt to your food when eating

  Use soy sauce sparingly: one teaspoon contains about 0.36gof sodium (equivalent to 0.9g salt)

   Buy fresh or frozen vegetables, or those canned without salt

   Rinse canned foods, such as beans, to remove excess salt

    Choose breakfast cereals that are lower in sodium

    Buy low or reduced sodium versions, or those with no salt added

Symptoms of increased salt intake include nausea, vomiting, diarrhoea and abdominal cramps. High concentrations of sodium in the body can also result from excessive water or fluid loss. Persistently high levels of sodium in the blood can result in swelling, high blood pressure, difficulty in breathing, and heart failure, and may be fatal.

A high dietary salt intake is an important causal factor in the development of hypertension (high blood pressure), which currently affects 32 per cent of men and 30 per cent of women in the UK. Hypertension increases the risk of strain on the heart, enlarges the heart muscle, and prevents an adequate blood (and therefore oxygen) supply from reaching the heart, and may lead to heart failure, angina or heart attack.

This is rare because our dietary intake is so high, but levels of sodium in the body can become too low as a result of prolonged illness. Sodium levels can also become low due to dehydration or excessive or persistent sweating, which may occur during very hot weather or affect marathon runners, athletes in triathlons, or people with certain forms of kidney disease, such as acute kidney failure.

Symptoms of a deficiency of sodium include headache, nausea and vomiting, muscle cramps, drowsiness, fainting, fatigue and possibly coma.

    More than 90 per cent of sodium occurs as salt.

    More than three quarters of salt intake is derived from processed foods, just under 15 per cent from natural sources, about 10 per cent is added during cooking or when eating and 1 per cent comes from tap water.

    Cereal products including breakfast cereals, bread, cakes and biscuits provide about a third of the salt in our diet.  Meat and meat products provide just over a quarter of the salt in our diet.

    In addition to sodium chloride, there is a wide variety of other forms of sodium in our diet, many of which are used as additives in food processing, usually to add flavour, texture or as a preservative. For example, monosodium glutamate is commonly used as a flavour enhancer.

 

Source: BBC

Nada Haj Khider

Pill shows innovative way of lowering blood sugar

The US Food and Drug Administration (FDA) on Friday approved a first-of-its-kind diabetes drug from Johnson & Johnson that uses a new method to lower blood sugar — flushing it out in patients’ urine.

The agency cleared J&J’s Invokana tablets for adults with Type 2 diabetes. The once-a-day medication works by blocking the kidneys from reabsorbing sugar, which occurs at higher levels in patients with diabetes than in healthy patients. Regulators highlighted the drug as the first in a new class of medications that could help address the growing US diabetes epidemic.

Analysts estimate Invokana could eventually grow into a blockbuster drug, generating more than $1 billion in sales annually for J&J.

People with type 2 diabetes are unable to properly break down carbohydrates, either because their bodies do not produce enough insulin or have become resistant to the hormone, which controls blood sugar levels. These patients are at higher risk for heart attacks, kidney problems, blindness and other serious complications. Diabetics often require multiple drugs with different mechanisms of action to control their blood sugar levels.

Invokana differs from older drugs that work by shrinking the amount of sugar absorbed from food and stored in the liver. The most common side effects of Invokana are yeast infections and urinary tract infections, due to the higher amounts of sugar passing through a patient’s urine. The drug also can cause a sudden drop in blood pressure when a patient stands up, which can lead to dizziness or fainting, according to the FDA.

The FDA said it approved the drug based on nine studies involving more than 10,000 patients. The studies showed that Invokana, both alone and in combination with other diabetes drugs, helped control blood sugar levels.

“We continue to advance innovation with the approval of new drug classes that provide additional treatment options for chronic conditions that impact public health,” said Dr Mary Parks, director of the FDA’s division of endocrinology products.

Regulators are requiring Johnson & Johnson to conduct five follow-up studies to assure the drug’s safety. The company will track rates of heart problems, cancer, pancreatitis and liver abnormalities, among other issues.

In recent years, the FDA has required companies developing diabetes drugs to closely monitor all heart-related side effects in patients. That’s because diabetes medicines are taken daily for many years, and one former blockbuster, GlaxoSmithKline PLC’s Avandia, was linked to higher heart attack risks.

Associated Press

B.N

traffic pollution causes Childhood Asthma

New research conducted in 10 cities has estimated that 14% of chronic childhood asthma is due to exposure to traffic pollution near busy roads.

 The results are comparable to the burden associated with passive smoking: the World Health Organization estimates that between 4% and 18% of asthma cases in children are linked to passive smoking.

Until now, traffic pollution was assumed to only trigger asthma symptoms and burden estimations did not account for chronic asthma caused by the specific range of toxicants that are found near heavily used roads.

The researchers used a method known as population-attributable fractions to assess the impact of near-road traffic pollution. This calculates the proportional reduction in disease or death that would occur if exposure to a risk factor were reduced to a lower level .

The new research used data from existing epidemiological studies which found that children exposed to higher levels of near-road traffic-related pollution also had higher rates of asthma, even when taking into account a range of other relevant factors such as passive smoking or socioeconomic factors.

The researchers aimed to take these findings further and estimate how many asthma cases could be avoided if exposure was removed.

The results found that 14% of asthma cases across the 10 cities could be attributed to near-road traffic pollution. The findings also take into account differences in the health of the overall population in different cities.

Lead author, Dr Laura Perez at the Swiss Tropical and Public Health Institute, said: "Air pollution has previously been seen to trigger symptoms but this is the first time we have estimated the percentage of cases that might not have occurred if people had not been exposed to road traffic pollution. In light of all the existing epidemiological studies showing that road-traffic contributes to the onset of the disease in children, we must consider these results to improve policy making and urban planning."

Nada Haj Khider

Source : Science Daily