Antibiotics not for running noses, warn doctors

Running noses and green phlegm do not mean patients need antibiotics, say doctors and public health experts.

It was described as a "prevailing myth" that the drugs were needed to treat such infections.

Public Health England and the Royal College of General Practitioners said the symptoms were often caused by viruses.

And the use of antibiotics was leading to resistance, they said.

Public Health England said its own research showed that 40% of people thought antibiotics would help a cough if the phlegm was green, while very few thought it would make a difference to clear-coloured phlegm.

Dr Cliodna McNulty, from the organization, said: "It's a prevailing myth that anyone with green phlegm or snot needs a course of antibiotics to get better.

"Most of the infections that generate lots of phlegm and snot are viral illnesses and will get better on their own although you can expect to feel pretty poorly for a few weeks.

"The problems of antibiotic resistance are growing. Everyone can help by not using antibiotics for the treatment of uncomplicated infections."

Taking antibiotics affects the trillions of bacteria that naturally live in the human body and can lead to resistance.

Dr Maureen Baker, chairwoman of the Royal College of GPs, said: "Overuse of antibiotics is a serious public health concern.

"Infections adapt to antibiotics used to kill them and can ultimately make treatment ineffective so it's crucial that antibiotics are used appropriately."

The green colour in phlegm and snot is the result of a protein made by the immune system to fight infection. The latest advice comes on European Antibiotics Awareness Day.

Source : BBC

N.H.Khider

Evolution of Bitter Taste Sensitivity

It's no coincidence that the expression "to leave a bitter taste in one's mouth" has a double meaning; people often have strong negative reactions to bitter substances, which, though found in healthful foods like vegetables, can also signify toxicity. For this reason, the ability to sense bitterness likely played an important role in human evolution.

A new study by University of Pennsylvania scientists provides new evidence underlining the significance of bitter taste perception. Their work suggests that a genetic mutation that makes certain people sensitive to the taste of a bitter compound appears to have been advantageous for certain human populations in Africa. Yet the reason why this trait was selected may not have to do with just taste. Instead, the molecular receptor under study may also play important roles in immune response or metabolism.

"We're starting to understand that these taste receptors are involved in so many functions other than just oral sensory perception," said Michael Campbell, lead author on the study and a postdoctoral fellow in Penn's Perelman School of Medicine's Department of Genetics.

The study, published in the journal Molecular Biology and Evolution, represents the first time that this bitter-taste sensing gene, TAS2R16, was studied in a large set of ethnically and culturally diverse African populations.

"Because Africa is the site of origin of all modern humans," said Sarah Tishkoff, the study's senior author and a Penn Integrates Knowledge Professor with appointments in the School of Arts and Sciences' Department of Biology and Penn Medicine's Department of Genetics. "Africans are going to have a large amount of diversity and non-Africans are going to have a subset of that diversity. In Africa, you get an opportunity to observe how these genetic variants are influencing phenotypes that you wouldn't have if you were only studying non-Africans."

Campbell, Tishkoff and other Penn researchers collaborated with Paul Breslin of Rutgers University and Monell Chemical Senses Center, as well as scientists from Addis Ababa University, France's Musée de L'Homme, Integral Molecular Inc., the Kenya Medical Research Institutes, Cameroon's Ministry of Scientific Research and Innovation, Tanzania's Muhimbili University of Health and Allied Sciences and the National institute on Deafness and Other Communication Disorders.

The work builds on a previous study by the group, which explored the evolutionary history of a gene called TAS2R38, responsible for the ability to perceive the bitter tasting compound PTC. In that research, published in Molecular Biology and Evolution in 2012, the geneticists discovered that something other than taste perception must have driven the selection of that gene.

The current work examines the related gene TAS2R16, which codes for a molecular receptor that binds salicin. Salicin is a chemical found naturally in willow bark, the source of aspirin. It acts as an anti-inflammatory but in large doses can be toxic. It is also found in many nuts, fruits and vegetables.

To understand the patterns of variation at TAS2R16 in humans globally, the researchers collected DNA from 595 people in 74 populations across Africa with diverse lifestyles, such as pastoralism, hunting-gathering and agriculture. They sequenced the stretch of DNA encompassing the TAS2R16 gene in all of these individuals and also examined previously collected DNA from 94 non-Africans from the Middle East, Europe, East Asia and the Americas and found 15 variants total, most of which were only found in Africa.

In addition, the researchers asked 296 of the Africans sampled to perform "taste tests" of progressively more concentrated solutions of salicin and report when they could detect a bitter taste. The team also performed a cellular analysis, led by Integral Molecular scientists, to see the molecular effects of different TAS2R16 mutations.

"The taste testing shows that the mutations in TAS2R16 had functional significance for the bitter taste perception system," Breslin said. "In this case, the mutation caused a gain of taste function."

When the researchers "mapped" individuals' genetic profiles onto their tasting ability, they found a strong correlation between one of the 15 variants and an increased sensitivity to salicin. The cell-based analysis offered an explanation for this sensitivity: cells with this genetic mutation had nearly twice as many receptors for salicin on their membranes as did cells with other forms of the TAS2R16 gene.

On a population level, the researchers found that the "high-sensitivity" variant for salicin was more prevalent in individuals from East Africa than in those from West Central or Central Africa, and non-Africans possessed only the "high-sensitivity" version of the gene. What's more, in East Africans this high-sensitivity variant, which arose roughly 1.1 million years ago, showed signs of being under a force of natural selection in humans, suggesting it conferred an evolutionary advantage at some point during our past.

"That's another sign that this variant must be tremendously important for human survival because it evolved in our human ancestors so long ago and carried over to us," Campbell said.

The geographic structure of TAS2R16 variants contrasts with the previous work on TAS2R38, variants of which did not appear to fall into any clear geographic pattern. These differences between two genes that both relate to bitter taste perception offer more support to the idea that taste was not the only force driving the evolution of this gene.

"The types of populations we're studying are diverse and they have diverse diets," Tishkoff said, "suggesting that there is likely something else going on here. By getting a handle on how much variation is in these populations, where it is located and what are the particular signatures of selection, it might start giving us clues as to what we should be looking at in terms of the biomedical or physiological significance of these genes."

Source: Science Daily

R.S

Most Painful Days of Your Life School Desks and Chronic Back Pain

Undersize school chairs, low desks and overweight backpacks are contributing to chronic back pain in adolescents, according to a study from researchers in Portugal to be published in the International Journal of Human Factors and Ergonomics.

Ana Assunção and colleagues in the Biomechanics and Functional Morphology Laboratory, at the University of Lisbon, carried out a cross-sectional study of 138 twelve to fifteen-year olds of differing maturity to examine the effect of a mismatch between school furniture dimensions, the weight of their school bags and the student's anthropometric characteristics.

They found that almost two thirds (80) of the students studied suffered from back pain and that large differences between desk height and elbow height was associated with a greater likelihood of the adolescents having this problem. Girls were more likely to suffer from the desk height discrepancy than boys; 59% of girls and 47% of boys. "Our results also showed that there was no association between backpack weight, body mass index (BMI) and back pain," the team says.

"These results highlight the importance to study the school environment to establish preventive programs for back pain in youths," the researchers say. They point out that the number of school-aged children, and adolescents, reporting frequent episodes of back and neck pain and headache has increased in the last few decades and that it is now recognized that people suffering during childhood are likely to suffer back pain in adulthood too, unless the problem is treated appropriately.

The researchers concede that back pain is, of course, a multi-factorial problem that results from an interaction of different risk factors, such as, age, family clinical history, injury, gender, lifestyle, sport, stress and anxiety. However, ergonomic factors such as a student's desk and chair dimensions are also likely to play a significant role. This is especially true given that students spend considerable amounts of time sitting at a desk, with physical activity and sports at a low in many educational establishments despite today's supposed drive to make everyone more active. The World Health Organization recommends at least 60 minutes of moderate to vigorous physical activity every day.

"These results highlight how relevant it is to study the school environment in order to establish preventive programs for back pain in children and adolescents, not only health wise, but also in terms of school education," the team asserts. "These results show the importance of promoting healthy lifestyles in what concerns physical activity and a balanced nutrition."

Source: sciencedaily.com

B.N

 

Scientists Develop Candidate Vaccine Against Respiratory Syncytial Virus

 An experimental vaccine to protect against respiratory syncytial virus (RSV), a leading cause of illness and hospitalization among very young children, elicited high levels of RSV-specific antibodies when tested in animals, according to a report in the journal Science.

Early-stage human clinical trials of the candidate vaccine are planned. Scientists from the Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, built on their previous findings about the structure of a critical viral protein to design the vaccine. The team was led by Peter D. Kwong, Ph.D., and Barney S. Graham, M.D., Ph.D.

In the United States, RSV infection is the most common cause of bronchiolitis (inflammation of small airways in the lungs) and pneumonia in children less than one year old and the most common cause for hospitalization in children under five. Worldwide, it is estimated that RSV is responsible for nearly 7 percent of deaths in babies aged 1 month to 1 year; only malaria kills more children in this age group. Others at risk for severe disease following RSV infection include adults over age 65 and those with compromised immune systems.

"Many common diseases of childhood are now vaccine-preventable, but a vaccine against RSV infection has eluded us for decades," said NIAID Director Anthony S. Fauci, M.D. "This work marks a major step forward. Not only does the experimental vaccine developed by our scientists elicit strong RSV-neutralizing activity in animals, but, more broadly, this technique of using structural information to inform vaccine design is being applied to other viral diseases, including HIV/AIDS."

Earlier this year, the VRC team obtained atomic-level details of an RSV protein -- called the fusion (F) glycoprotein -- bound to a broadly neutralizing human RSV antibody. The protein-antibody complex gave scientists their first look at the F glycoprotein as it appears before it fuses with a human cell. In this pre-fusion shape, F glycoprotein contains a region vulnerable to attack by broadly neutralizing antibodies (antibodies able to block infection from the common strains of RS).

Once RSV fuses with a cell, this vulnerable area, named antigenic site zero by the researchers, is no longer present on the rearranged F protein. In natural RSV infection, the immune system produces antibodies against both the pre-fusion and post-fusion forms of F glycoprotein, but the antibodies to antigenic site zero, which is only present on the pre-fusion form, have much stronger neutralizing activity. Therefore, a vaccine against RSV would have greater chance of success by eliciting antibodies directed at F glycoprotein in its pre-fusion configuration.

In their current publication, Drs. Kwong and Graham describe how they used this structural information to design and engineer F glycoprotein variants that retained antigenic site zero even when no antibody was bound to it. The goal was to create stable variants that could serve as the foundation for a vaccine capable of eliciting a potent antibody response. The researchers designed more than 100 variants; of these, 3 were shown by X-ray crystallography to retain the desired structure. The engineered variants were then used as vaccines in a series of experiments in mice and rhesus macaques.

In both mice and macaques, the researchers found that the more stable the protein, the higher the levels of neutralizing antibodies elicited by vaccination. The levels of antibody made in response to one of the engineered F glycoproteins were more than 10 times higher than those produced following vaccination with post-fusion F glycoprotein and well above levels needed to protect against RSV infection.

"Here is a case in which information gained from structural biology has provided the insight needed to solve an immunological puzzle and apply the findings to address a real-world public health problem," said Dr. Graham. He and the VRC scientists are continuing to refine the engineered F glycoproteins and hope to launch early-stage human clinical trials of a candidate RSV vaccine as soon as clinical grade material can be manufactured, a process that takes about 18 to 24 months to complete.

"Previously, structure-based vaccine design held promise at a conceptual level," said Dr. Kwong. "This advance delivers on that promise and sets the stage for similar applications of structure-guided design to effective vaccines against other pathogens."

Dr. Fauci added, "This latest advance underscores the advantages of the VRC's organizational design, where experts in RSV virology, vaccinology and clinical studies, such as Dr. Graham, are in daily contact with Dr. Kwong and others who are experts in structural biology. Such close collaboration across disciplines allows for rapid testing of new approaches to a given problem."

Source :Science Daily

R.Sawas

National Vaccination Campaign Targeting 1.6 Million Children

DAMASCUS,(ST)_ Health Ministry yesterday  launched a national vaccination campaign against measles and polio in the health centers and temporary residence that will continue until  November 21st..

Minister of Health Dr. SaadNaev stressed , during his  tour on Kudsia suburb health center  and  temporary accommodation centers  that the  campaign is targeting 1.6 million  children in health centers and medical teams distributed all over the country 's provinces.

The minister pointed out that the campaign in temporary accommodation  centers targeted  children from one year old to  under 15 year- s old with  MMR vaccine  for  measles, rubella , mumps and vitamin A and children from the age of one day-to under five years  with oral paralysis vaccine  while at health centers, children from one day old -to- under  five years are given  oral polio vaccine , regardless of previous doses and children from year old to pre-schooling  age  are immunized by MMR vaccine and vitamin A .

The Minister of Health pointed out  that " the ministry imported  vaccines from best international companies and offered it free  for all children , at costs that  exceed billions  Syrian pounds , annually .

For her  part, UNICEF 's Deputy Resident Representative in Damascus HamidaRamadanistressed  that the organization seeks to support the efforts of the Ministry of Health and other partners to reach  and immunize every  Syrian child, especially under the current circumstances , where some families find it difficult to access medical services.

Dr. Tariq Abdul-Rahman of the regional office of the World Health Organization (WHO)  in Cairo noted that  the good cooperation between the Ministry of Health and international organizations will contribute to the success of the campaign, but "the concern comes from the possibility of lack of access to all areas under the current difficult circumstances ."

Abdul-Rahman said that the importance of the campaign comes from the timing , as a result of current circumstances,  Syria is  experiencing a decline in the percentage of children immunized and therefore , efforts should be concerted to raise the  percentage  of immunized children  again.

Last Sunday, the  Ministry of Health in collaboration with the Ministry of Education and  UNICEF launched a vaccination campaign in the country 's schools against measles, rubella , mumps , targeting 800 thousand children from sixth grade class  to the ninth , which will last until the end of the first schooling semester.

In Homs, director of health care department  Dr. Abdul MomenQashlaq  said that the  " campaign is expected  to include 180 thousand children under the age of five against polio and 130 thousand children against measles , rubella, mumps ," pointing out that he coordinated  with the Red Crescent branch in Homs to deliver the vaccine to unsafe areas , so as to ensure that all children are vaccinated .

Meantime, Aleppo Health Directorate Aleppo started yesterday the national vaccination campaign against measles and polio in the health and temporary accommodation centers that are expected to target about  734.749 children, according  to director Dr. Waddah Hussein.

Simultaneously, Sweida Health Directorate launched   yesterday the national vaccination campaign against measles and polio , targeting  44 thousand children under the age of five in addition to 6 thousand children under the age of five years in temporary accommodation centers.

T. Fateh