Scientists Discover How Mosquitoes Detect Human Sweat

Zika, w.h.o

 

Scientists have known for decades that mosquitoes are attracted to the lactic acid contained in human sweat, but in the era before advanced genetics, the precise mechanism had remained a mystery.

Now, a team of researchers at Florida International University have discovered the olfactory receptor that allows the disease-carrying insects to hone in on our odor — and how to switch it off.

They published their work on the Aedes aegypti mosquitoes, known for spreading deadly illnesses like Zika, dengue and yellow fever, in the journal Current Biology on Thursday.

The team, led by FIU biologist Matthew DeGennaro, identified the guilty receptor as Ionotropic Receptor 8a, or simply IR8a, through a process of elimination that began in 2013 when DeGennaro was able to create the world’s first mutant mosquito, removing a gene to investigate how its absence affected the insect.

Tasked with investigating IR8a, DeGennaro’s PhD student Joshua Raji began by carrying out an exposure experiment using his own arm, and found the mutant mosquitoes were significantly less attracted to him than wild ones.

The outcome was confirmed through testing on 14 additional subjects.

“People have been looking for a receptor for lactic acid since the 1960s,” DeGennaro told AFP.

The findings could offer a roadmap for a new generation of attractants that lure adult specimens into traps for population control, as well as advanced repellants that make people invisible to mosquitoes — though that could be some way away.

“It’ll take years, but we are definitely a step closer,” said DeGennaro.

AFP

Parkinson’s Disease May Start In Appendix, Study Finds

Parkinson’s disease has long been considered a disease of the brain, but research out Wednesday found it may start in the gut — specifically in the appendix, a tiny organ near the large intestine.

Using health registries in Sweden and the United States, researchers found that those who had their appendix removed in early adulthood generally saw their risk of developing the incurable neurodegenerative disorder cut by 19 per cent, said the study in the journal Science Translational Medicine.

In rural areas of Sweden, where people may be more exposed to pesticides — which have been shown to play a role in Parkinson’s — the effect was even greater: a 25 percent lower risk.

“Among people who did develop Parkinson’s disease, we found that the age of onset was delayed by an appendectomy on average by 3.6 years,” study author Viviane Labrie, assistant professor at Van Andel Research Institute in Michigan, said during a conference call with reporters.

“Our studies suggest that the appendix might be a tissue site that plays a role in the early events or initiation of Parkinson’s disease.”

Parkinson’s affects millions of people worldwide. Some of the celebrities afflicted include actors Michael J. Fox and Alan Alda, singer Neil Diamond and the late boxer Muhammad Ali.

– Useless organ? –
Often, the appendix is considered a useless organ.

But researchers say it is a storage site for gut bacteria, is linked to immune response, and appears to be a gathering place for a key protein implicated in Parkinson’s, known as alpha-synuclein.

Knowing that people with Parkinson’s also suffer from gastrointestinal disorders like constipation at least 10 years before the disease’s better known symptoms like tremors, stiffness, and poor balance surface, researchers decided to take a closer look at the appendix and its potential role.

They found that nearly everyone has signs of clumped up alpha-synuclein present in their appendix.

But not everyone goes on to develop Parkinson’s, for reasons that still aren’t well understood.

“We think that in rare events, if it (alpha-synuclein) were to escape the appendix and enter the brain, this could lead to Parkinson’s disease,” Labrie told reporters.

In fact, “alpha-synuclein is a protein that doesn’t like to stay put,” she added.

“It’s able to move from neuron to neuron.”

Experiments have shown the protein “can travel up the nerve” that connects the gastrointestinal tract to the brain,” she explained.

“If it were to enter the brain, it can seed and spread from there and have neurotoxic effects that could eventually lead to Parkinson’s disease.”

Researchers say it’s possible that someday, drug therapies could be developed to cut down on the protein’s accumulation in the appendix, thereby lowering the risk of Parkinson’s.

In the meantime, experts stressed they do not recommending that anyone go out and get an appendectomy to cut the risk of Parkinson’s, as more research is needed.

– Gut-brain connection –
According to Kevin McConway, emeritus professor of applied statistics at The Open University, the study goes “part of the way to establishing a reason why the relationship between appendix removal and Parkinson’s disease might be one of cause and effect.”

McConway, who was not involved in the research, added that “several previous studies have looked for relationships between appendix removal and various other diseases, including heart disease as well as various diseases of the gut.”

“For some of these diseases, having your appendix out was associated with a reduced disease risk, but in others, including heart disease, it was associated with an increased risk,” he said.

Indeed, a smaller study using Danish health registries, published in 2016, found that appendectomies were associated with a small increase in Parkinson’s disease risk 10 or more years after surgery.

According to Labrie, the main difference is that her study spanned 52 years of follow-up, “which allowed us to see the lowered risk of an appendectomy on Parkinson’s disease risk,” compared to the Danish study, which lasted about three decades.

The current study covered some 1.7 million people in Sweden, along with a second US dataset encompassing 849 people.

Even though the new research may not offer the last word on the matter, it does bolster what scientists know about the close connection between the brain and the gut.

The intestinal tract actually contains a lot of neurons, which are linked back to the brain via the vagus nerve.

“Some scientists have called the intestine the second brain, because of the number of neurons that are present in there,” said co-author Patrik Brundin, director of the Center for Neurodegenerative Science at Van Andel Research Institute.

AFP

Breakthrough Treatment Helps Paralysed Patients Walk

This handout photo released on October 31, 2018, by the Federal Polytechnique School of Lausanne (EPFL)/ The Lausanne University Hospital (CHUV) shows David Mzee, who suffered full paralysis of his left leg after an accident in 2010, at the Lausanne University Hospital in Spring 2018. EPFL / AFP

 

A breakthrough treatment involving electrical stimulation of the spine has enabled paralysed patients to walk again, apparently reactivating nerve connections and providing hope for people even years after accidents.

A team including neurosurgeons and engineers used targeted electrical pulses to achieve the results, triggering individual muscles in a sequence, the way the brain would.

The pulses are produced by an implant placed over the spine in careful alignment with areas that control the muscles in the lower body.

And so far, the results are promising.

“This clinical trial has given me hope,” said Gert-Jan Oskam, 35, who was told he would never walk again after a traffic accident in 2011.

After five months of treatment, he can now walk short distances even without the help of electrical stimulation.

It’s the culmination of “more than a decade of careful research,” Gregoire Courtine, a neuroscientist at the Swiss Federal Institute of Technology who helped lead the research, told AFP.

Previous trials have used so-called continuous electrical stimulation of the spine, which worked well in rats but produced less impressive results in humans.

After several months of training with the targeted pulses, however, “our three participants were able to activate their previously paralysed muscles without electrical stimulation,” said Courtine.

“The result was completely unexpected,” he added, in a video released with the publication of the research in the journal Nature Thursday.

“They could even take a few steps overground without any support, hands-free. For me, seeing this recovery was amazing.”

Reconnecting nerve pathways

Footage from the study shows clearly the way the targeted stimulation differs from the continuous pulses.

With the targeted stimulation, a patient walks in an almost ordinary fashion, his feet rolling down and up as he steps.

The continuous stimulation, by contrast, produces jerkier movement, with his feet dragging and unbalancing him.

And the targeted pulsing, combined with a programme of extensive physiotherapy, was apparently able to reactivate nerve connections that became dormant when patients were injured.

David Mzee, 28, suffered full paralysis of his left leg after an accident in 2010, but after the five-month programme, he can walk for up to two hours with a walker using electrical stimulation, or take steps over shorter distances by himself.

The simulation begins with a pulse directed at a muscle to prompt the patient to begin movement; for example, a step.

Sensors at the feet detect the movement as the initial phase of a step and send additional targeted pulses to trigger the muscle movements required to complete the step, and repeat it.

At the same time, patients think about moving those muscles and stepping.

Because the neurons in the brain fire at almost the exact same time as the electrical pulses stimulate the muscles, the technique appears to eventually “reconnect” the brain and the muscles.

Patients can then command the muscle movement even without the electrical triggers.

David Mzee, who suffered full paralysis of his left leg after an accident in 2010, poses in Lausanne, during the summer of 2018.  Photo: EPFL / AFP

‘A lot of work to do’

“It was incredible to see all these patients moving their legs without electrical stimulation,” said Jocelyne Bloch, a neurosurgeon at the University Hospital of Lausanne, who helped lead the study.

In an independent evaluation, Chet Moritz, an associate professor at the University of Washington’s rehabilitation medicine department, praised the work.

“The field of spinal cord injury is poised to take a giant leap forward in the treatment of what was until very recently considered incurable paralysis,” he wrote.

Courtine warned however that it remained “very important to calibrate expectations,” pointing out that all three patients still rely mostly on their wheelchairs.

The study also focused only on patients who had retained some feeling in their lower body.

Going forward, Courtine said he hoped to see the technique combined with biological treatments involving nerve repair.

He and Bloch have founded a start-up that will refine the treatment and test it on people shortly after spinal cord injuries, when the technique is likely to be more successful.

“There is still a lot of work to do to change the lives of these people,” Courtine said.

 

AFP

Meat-Heavy, Low-Carb Diets Can ‘Shorten Lifespan’ – Study

AFP Photo

 

Middle-aged people who get roughly half their daily calories from carbohydrates live several years longer on average than those with meat-heavy low-carb diets, researchers reported Friday.

The findings, published in The Lancet medical journal, challenge a trend in Europe and North America toward so-called Paleo diets that shun carbohydrates in favour of animal protein and fat.

Proponents of these “Stone Age” diets argue that the rapid shift 10,000 years ago — with the advent of agriculture — to grains, dairy and legumes has not allowed the human body enough time to adapt to these high-carb foods.

For the study, receiving less than 40 percent of total energy intake from carbohydrates qualified as a low-carb regimen, though many such diets reduce the share to 20 percent or less.

At the other extreme, a 70 percent or higher share of carbohydrates — such as pasta, rice, cakes, sugary drinks — can also reduce longevity, but by far less, the scientists found.

“Low-carb diets that replace carbohydrates with protein or fat are gaining widespread popularity as a health and weight loss strategy,” said lead author Sara Seidelmann, a researcher at Brigham and Women’s Hospital in Boston.

“However, our data suggests that animal-based low carbohydrate diets might be associated with shorter overall lifespan and should be discouraged.”

Replacing meat with plant-based fats (such as avocados and nuts) and proteins (such as soy products and lentils) reduces the risk of mortality, Seidelmann and her team found.

The optimal balance of food groups for longevity remains hotly debated.

Many studies have concluded that eating carbohydrates in moderation — 45 to 55 percent of total calorie intake — is best, but others report improved short-term, cardio-metabolic health with high-protein, high-fat diets.

Measures of metabolic health include blood pressure, good and bad cholesterol, and blood sugar levels.

Plant vs animal protein

“Low carbohydrate dietary patterns favouring animal-derived protein and fat sources, from sources such as lamb, beef, pork, and chicken, were associated with higher mortality,” the study said.

“Those that favoured plant-derived protein and fat intake, from sources such as vegetables, nuts, peanut butter, and whole-grain breads, were associated with lower mortality,” it said, adding that this suggested “the source of food notably modifies the association between carbohydrate intake and mortality.”

Seidelmann and colleagues poured over the medical histories of nearly 15,500 men and women who were 45-64 when they enrolled — between 1987 and 1989 — in a health survey spread across four locations in the United States.

Participants filled out detailed questionnaires about their dietary habits — what foods, how much, how often, etc.

Over a 25-year follow-up period, more than 6,000 of the men and women died.

People who got 50-55 percent of their calories from carbohydrates outlived those with very low-carb diets, on average, by four years, and those with high-carb diets by one year.

A review of medical records for an additional 432,000 people from earlier studies confirmed the results, which are also in line with World Health Organization (WHO) recommendations.

“There is nothing to be gained from long-term adherence to low-carbohydrate diets rich in fats and proteins from animal origins,” said Ian Johnson, a nutrition researcher at Quadram Institute Bioscience in Norwich, England, commenting on the research, in which he did not take part.

But carb quality, not just quantity, is crucial he added.

“Most should come from plant foods rich in dietary fibre and intact grains, rather than from sugary beverages or manufactured foods high in added sugar.”

Fibres also help maintain a healthy gut flora, now considered to be a major factor in health and disease.

AFP

Pin-Prick Blood Test Detects Deadly Sepsis – Study

 

Scientists on Monday unveiled a quick, cheap way to detect sepsis, a life-threatening condition in which the body is attacked by its own immune system.

In clinical trials at Massachusetts General Hospital in Boston, the researchers — analysing a single drop of blood with a thumb-size filtering device — singled out sepsis patients in a matter of hours with 95 percent accuracy.

Currently, nearly a third of sepsis patients are misdiagnosed with devices that can take days to yield results.

For every hour that a sepsis diagnosis is delayed, the risk of death increases by nearly eight percent, previous research has shown.

“We believe that this approach may allow us to identify patients at risk of developing sepsis earlier than any other method,” said Jarone Lee, director of an intensive care unit at Massachusetts General and co-author of a study in Nature Biomedical Engineering.

Sepsis occurs when the body’s immune system runs amok in reaction to a major infection, leading to low temperature, vomiting and — in extreme cases — tissue damage, organ failure and death.

The condition affects at least 30 million people worldwide every year, and leaves five million dead, according to a recent study in the American Journal of Respiratory and Critical Care Medicine.

Up to half of people who survive severe sepsis suffer from post-traumatic stress disorder, chronic pain, organ dysfunction or amputations, according to the Sepsis Alliance, a charitable advocacy organisation in the United States.

The test devised by the researchers isolates a specific type of white blood cell, called a neutrophil.

In earlier research, senior author Daniel Irimia, a surgeon at the hospital and assistant professor at Harvard Medical School, noticed that spontaneous movements of these white blood cells corresponded to the likelihood that patients would develop sepsis.

Irimia and colleagues developed a small, hand-held device that coaxes neutrophils through a microscopic maze.

“The striking performance” of the device “brings into focus the fundamental role that neutrophils play during sepsis,” Irimia said in a statement.

Follow-up tests with a larger and more diverse group of volunteers are underway.

Spanish Flu: More Deadly Than World War I – Study

File Photo.

 

The Spanish flu outbreak 100 years ago is the modern world’s deadliest epidemic, its toll of more than 50 million surpassing that of World War I.

Here is some background.

Why ‘Spanish flu’?

Countries caught up in the 1914-1918 war censored information about the extent to which the flu outbreak was ravaging their troops.

Spain was, however, neutral in the conflict and had no such restrictions. Media reporting on the effects of 1918-1920 flu outbreak there resulted in the false impression that Spain was particularly hard hit, giving rise to the nickname.

Where did it come from?

The geographic origin of the epidemic is not certain and no samples remain for further study.

The first cases were recorded in March 1918 among soldiers in Kansas in the United States. It may have spread to Europe with the troops.

The virus is the type A (H1N1), the same strain behind the swine flu outbreak of 2009. That outbreak claimed about 18,500 lives in 214 countries, according to the World Health Organization (WHO), although later estimates say the final toll could be around 200,000.

It is believed that all existing type A flu viruses come directly or indirectly from the 1918 virus but are less harmful.

– Rapid spread –

Spanish flu spread in three waves, the first in the Northern Hemisphere spring of 1918 being highly contagious but causing few deaths.

The second, more virulent, emerged later in the year and “swept the globe in six months, killing over 10,000 people per week in some US cities at the height of the pandemic,” says a paper on the US National Academy of Sciences site.

“Emotional reports of fit and healthy soldiers falling down on parade and dying the same or the next day are recorded,” another article says.
The third wave followed in early 1919.

Few regions were untouched. Australia was among the countries least affected because of its strict quarantine measures.

– A ghastly toll –

There is no precise death toll for the Spanish flu outbreak.

All estimates say that it caused many more deaths than World War I, when around 10 million soldiers were killed along with several million civilians.
The WHO regularly states “more than 50 million” died from the flu and one 2002 study, cited by many others since, says the toll may have been as high as 100 million.

About 500 million people, estimated at one-third of the world’s population at the time, were infected, says a 2006 report entitled “1918 Influenza: the Mother of All Pandemics”.

“Much of the high death rate can be attributed to crowding in military camps and urban environments, as well as poor nutrition and sanitation, which suffered during wartime,” the Smithsonian Institute says.

The virulent form of the virus acted quickly, causing the lungs to fill with fluid and suffocating victims, some of whom died within days of their first symptoms.

– The victims –

While flu epidemics today tend to strike mainly young children and the elderly, the Spanish flu hit hardest among young adults aged between 20 and 40.

Its high-profile victims reportedly include: Austrian artist Egon Schiele (1918); French poet Guillaume Apollinaire (1918); Donald Trump’s grandfather Frederick Trump (1918); Brazilian president Francisco de Paula Rodrigues Alves (1919).

The League of Nations, the forerunner of the United Nations, created in 1922 a health committee in part to respond to the need to fight such epidemics. It evolved into today’s WHO.

News Study Reveals Pacific Island Bones Are Likely Those Of Amelia Earhart

In this handout file photo obtained June 09, 2015, an undated 1930’s photo shows US aviator Amelia Earhart next to her Lockheed 10 Electra.

Bones found on a remote South Pacific island that were originally believed to be those of a man may in fact be those of famed aviatrix Amelia Earhart, who disappeared in the area in 1937, according to a new study.

Richard Jantz, professor emeritus of anthropology at the University of Tennessee, used modern bone measurement analysis to determine the bones were likely those of Earhart, who went missing while on a pioneering round-the-world flight with navigator Fred Noonan.

Earhart’s disappearance is one of the most tantalizing mysteries in aviation lore, fascinating historians for decades and spawning books, movies and theories galore.

The prevailing belief is that Earhart, 39, and Noonan, 44, ran out of fuel and ditched their twin-engine Lockheed Electra in the Pacific Ocean near remote Howland Island while on the third-to-last leg of their epic journey.

One of the most popular theories is that Earhart and Noonan crash-landed on uninhabited Gardner Island, now known as Nikumaroro, part of the Republic of Kiribati, where she survived briefly as a castaway.

A 1940 British Colonial Service expedition to the island found a human skull, bones, part of the sole of a woman’s shoe, a box for a sextant and a bottle of Benedictine.

The bones were shipped to Fiji and examined in 1941 by Dr. David W. Hoodless, a professor of anatomy, who determined they were those of a stocky man.
The bones have since been lost.

Using a computer program called Fordisc, which estimates sex, ancestry, and stature from skeletal measurements, Jantz re-examined seven bone measurements done by Hoodless — four of the skull and three of the tibia, humerus, and radius bones.

‘Most convincing argument’

Comparing them to measurements of Earhart’s bone lengths based on photographs and examination of her clothing, he determined the bones were likely those of the aviatrix.

The bones have more similarity to Earhart than to 99 percent of individuals in a large reference sample, according to the study.

“This strongly supports the conclusion that the Nikumaroro bones belonged to Amelia Earhart,” Jantz said. “The bones are consistent with Earhart in all respects we know or can reasonably infer.”

“Until definitive evidence is presented that the remains are not those of Amelia Earhart, the most convincing argument is that they are hers,” he said.
“Forensic anthropology was not well developed in the early 20th century,” Jantz wrote of the previous analysis of the remains.

“There are many examples of erroneous assessments by anthropologists of the period,” he said.

“We can agree that Hoodless may have done as well as most analysts of the time could have done, but this does not mean his analysis was correct,” Jantz said.
The study was published this week in the journal Forensic Anthropology of the University of Florida. It was conducted in collaboration with The International Group for Historic Aircraft Recovery (TIGHAR).

Earhart, who won fame in 1932 as the first woman to fly solo across the Atlantic, took off on May 20, 1937 from Oakland, California, hoping to become the first woman to fly around the world.

She and Noonan vanished on July 2, 1937 after taking off from Lae, Papua New Guinea, on a challenging 2,500-mile (4,000-kilometer) flight to refuel on Howland Island, a fly speck of a US territory between Australia and Hawaii.

They never made it.

No-Sweat Exercise May Prolong Life For The Elderly – Study

File Photo.

 

A few hours a week of light exercise – walking the dog, puttering about in the garden – lower the risk of death in older men, even if workouts are brief, researchers said Tuesday.

Their findings, reported in the British Journal of Sports Medicine, challenge two long-held assumptions about the benefits of physical activity for the elderly.

To improve health and reduce the risk of dying, according to many national health authorities, workouts must be strenuous and more long-lasting.

In Britain, for example, the elderly are advised to do moderate-to-intense exercise at least 150 minutes per week, divied up into segments of no less than 10 minutes.

“UK and US physical activity guidelines don’t mention any benefits of light activity,” lead author Barbara Jefferis, an epidemiologist at University College London, told AFP.

“When those guidelines were written there wasn’t enough evidence to make a recommendation.”

The study, which tracked 1,200 men without heart disease in their early 70s and late 80s, says such guidelines should be revised.

“The results suggest that all activities — no matter how modest — are beneficial,” Jefferis said.

Encouraging older adults to engage in no-sweat exercise also appears to be more realistic.

Only 16 percent of the volunteers lived up to current British exercise guidelines in sessions of at least 10 minutes. Two-thirds, however, did hit the weekly, 150-minute quota in shorter snippets of activity.

The research drew on data from the British Regional Heart Study, which began in 1978 with nearly 8,000 participants aged 40 to 59 from a couple dozen towns scattered across Britain.

In 2012, the 3,137 men still living underwent a physical check-up, and answered questions about their lifestyle and sleeping patterns.

Couch Potatoes

The study focused on 1,181 participants who wore an accelerometer — a device that tracks the volume and intensity of physical exercise — for seven days.

“The availability of body-worn activity monitors has enabled us to investigate whether light activity is linked to longevity,” said Jefferis.

The men, who averaged 78 years old, were monitored for five years, during which time 194 of them died.

The study showed that each additional 30 minutes-a-day of light-intensity exercise was associated with a 17 percent reduction in the risk of death.

As expected, a half-an-hour of moderate-to-vigorous activity reduced the risk by even more — 33 percent.

What counted, however, was the total time spent exercising, not how the time was divided up.

The men who engaged in brief, sporadic bouts of moderately intense activity — mowing the lawn, swimming, walking briskly — were as likely to avoid the grim reaper as men whose exercise time was parcelled into longer sessions.

For both groups, the chance of dying was 40 percent lower compared to full-time couch potatoes who hardly moved at all.

The authors cautioned that the structure of the study — the fact that it was observational, and not a clinical trial — made it impossible to describe the results in terms of cause-and-effect.

And in the comparison between older men who exercise — sporadically or regularly — and those who don’t, the fact that the participants who volunteers to wear accelerometers were in better health to begin with may have somewhat skewed the results.

It was also not clear whether the findings would apply to older women, though Jefferis said there was little reason to think they don’t.
“We didn’t have the necessary data for women,” she said.

Vaping May Boost Pneumonia Risk – Study

 

Vaping may help pneumonia-causing bacteria stick to cells lining the airways, likely boosting disease risk, researchers said Thursday.

A study published in the European Respiratory Journal did not directly compare vaping’s effect to that of smoking tobacco cigarettes.

But the findings did suggest that users of electronic cigarettes may be at higher risk of lung infection than people who do not vape, the research team reported.

“If you choose to take up e-cigarettes… this indicates a red flag that there may be an increased susceptibility” to pneumococcal bacteria, study co-author Jonathan Grigg of the Queen Mary University of London told AFP.

Grigg and a team conducted three types of experiment. One exposed human nose lining cells to e-cigarette vapour in the lab, another involved mice inhaling vapour and then being exposed to pneumococcal bacteria, the main cause of pneumonia.

A third trial studied the nose lining of 11 e-cigarette users compared to six non-vapers.

The team noticed a sharp increase in the amount of bacteria sticking to airway cells after e-cigarette exposure. Such adhesion has previously been shown to increase susceptibility to disease.

“Some people may be vaping because they think it is totally safe, or in an attempt to quit smoking, but this study adds to growing evidence that inhaling vapour has the potential to cause adverse health effects,” said Grigg.

“By contrast, other aids to quitting such as (nicotine) patches or gum do not result in airway cells being exposed to high concentrations of potentially toxic compounds.”

Less harmful?

Last month, a US study said vaping may increase cancer risk because it leads to DNA damage, despite containing fewer carcinogens than tobacco smoke.

That study, too, did not compare the effects of cigarette smoking directly to vaping.

Research in the journal Tobacco Control last October said a large-scale switch from tobacco to e-cigarettes would prevent millions of premature deaths by the year 2100, even assuming the gadgets are themselves not risk-free.

E-cigarettes, said to contain no tar and fewer toxins than tobacco cigarettes, were developed as a safer alternative to tobacco smoking.

But many people fear that a harmless veneer may make e-cigarettes a “gateway” for young people to lifelong nicotine addiction.

Commenting on the latest study, Peter Openshaw, an experimental medicine professor at Imperial College London, said any evidence that vaping raised lung infection risk was “only indirect”.

“Although it is possible that vaping might increase susceptibility to pneumonia, the effect is likely to be lower than from smoking itself,” he said via the Science Media Centre.

“This study should not be used as a reason to continue to smoke rather than vape –- the evidence to date is that e-cigarettes are far less harmful than smoking.”

AFP

‘Mutant flu’ Could Lead To More Effective Vaccine – Study

Photo: Miguel SCHINCARIOL / AFP

 

Experiments in lab animals have shown signs of success for a newly engineered flu virus that may lead one day to a more effective vaccine, researchers said Thursday.

Trials in humans are still a long way off, but the report in the US journal Science earned praise from experts who described it as a promising first step toward better prevention of the flu.

The World Health Organization considers the flu a major public health concern because it infects up to five million people with severe illness each year and causes up to 650,000 deaths.

“Because the variations of seasonal influenza viruses can be unpredictable, current vaccines may not provide effective protection against them,” said senior author Ren Sun, a professor of molecular and medical pharmacology at the David Geffen School of Medicine at the University of California, Los Angeles (UCLA).

“Previous pandemics and recent outbreaks of avian influenza highlight the need to develop vaccines that offer broader, more effective protection.”

Scientists arrived at the new approach by studying the genome of the flu virus and finding eight locations where they could disable its interferon-evasion functions, which affect whether a host can fight the illness or not.

Regular flu viruses are known for their ability to evade the immune system, but this engineered virus showed it “is hypersensitive to one of the body’s primary immune defense mechanisms,” said the report.

The mutant virus can “escape type 1 interferon (IFN-1) function, the body’s first line of defense against viruses.”

The engineered influenza virus “induced strong immune responses” in mice and ferrets without causing them to become ill, said the report.

It also protected against infection by different strains of the influenza virus.

More animal studies are planned before any vaccine based on the approach can be tried in people.

Jonathan Ball, professor of Molecular Virology at the University of Nottingham, described the paper as a “neat bit of science.”

“There’s still lots of work to do in order to progress this exciting development down the vaccine development pipeline,” said Ball, who was not involved in the research.

“These experiments were performed in laboratory animals and the proof of the pudding will be how the mutant virus performs in humans, especially those who have been exposed to multiple strains of virus and might already have built up a degree of immunity.”

Peter Openshaw, professor of experimental medicine at Imperial College London, described the work as a “collaborative tour de force between groups in North America and China,” that could lead the way to a universal flu vaccine.

“This advanced approach combines state of the art virology with incisive immunological techniques, potentially leading to greatly improved vaccines in the future,” he said.

However, there are “many hurdles to be overcome moving from pre-clinical through to clinical testing and ultimately to incorporation into standard vaccine schedules.”

Currently, influenza vaccines must be changed every year because the viruses are constantly evolving. Their effectiveness typically ranges from 30-60 percent.

 

AFP

Global Warming Outpacing Current Forecasts – Study

The ruins of a house smolder at night during the Creek Fire on December 5, 2017, in Sunland, California    Photo: David McNew/Getty Images/AFP

 

The United Nations’ forecast for global warming is about 15 percent too low, which means that end-of-century temperatures could be 0.5 degrees Celsius higher than currently predicted, according to a study released Wednesday.

This sobering verdict renders the already daunting challenge of capping global warming at “well under” 2.0 degrees Celsius (3.6 degrees Fahrenheit) — the cornerstone goal of the 196-nation Paris Agreement — all the more difficult, the authors say.

“Our results suggest that achieving any given global temperature stabilisation target will require steeper greenhouse gas emissions reductions than previously calculated,” they wrote.

A half-degree increase on the thermometer could translate into devastating consequences.

With only a single degree Celsius of global warming so far, the planet has already seen a crescendo of deadly droughts, heatwaves and superstorms engorged by rising seas.

Handout picture released by Chile’s National Forest Corporation (CONAF) showing the Grey Glacier detachment in the Torres del Paine National Park in Punta Arenas, Chile, on November 28, 2017.
HO / CONAF / AFP

 

The UN Intergovernmental Panel on Climate Change (IPCC), which provides the scientific foundation for global climate policy, projects an increase in the earth’s average surface temperature of about 4.5 Celsius by 2100 if carbon pollution continues unabated.

But there is a very large range of uncertainty — 3.2 to 5.9 degrees Celsius — around that figure, reflecting different assumptions and methods in the dozens of climate models the IPCC takes into account.

– Good science, bad news –

“The primary goal of our study was to narrow this range of uncertainty, and to assess whether the upper or lower end is more likely,” lead author Patrick Brown, a researcher at the Carnegie Institution for Science at Stanford University in California, told AFP.

By factoring in decades of satellite observations which track how much sunlight gets bounced back into space, the study showed that the more alarming projections are clearly aligned with that data and the warming that has been measured so far.

“Our findings eliminate the lower end of this range,” Brown said.

“The most likely warming is about 0.5 C greater than what the raw model results suggest.”

One scientist not involved in the research described it as a “step-change advance” in the understanding of how hot our planet is likely to become.

“We are now more certain about the future climate,” said William Collins, a professor of meteorology at the University of Reading.

“But the bad news is that it will be warmer than we thought.”

The study, published in the journal Nature, not only narrows the temperature, but reduces the degree of uncertainty as well.

“If emissions follow a commonly used ‘business as usual’ scenario, there is a 93 percent chance that global warming will exceed four degrees Celsius by century’s end,” said co-author Ken Caldeira, also from Stanford.

Up to now, there was barely more than a coin-toss certainty that the earth would breach the 4 C barrier by 2100 under that scenario.

AFP

How Volcanoes Helped Topple Ancient Egypt – Study

Mount Sinabung volcano spews thick smoke as seen from the Indonesian Tiga Pancur village in Karo, North Sumatra on October 17, 2017. IVAN DAMANIK / AFP

 

Sun-choking debris cast off by volcanoes more than 2,000 years ago starved headwaters feeding the Nile river and hastened the downfall of ancient Egypt’s last kingdom, researchers said Tuesday.

Eruptions in the 3rd- and 1st-century BC — including one of the biggest blasts in the last 2,500 years — coincided with crop failures, large-scale revolts, and the withdrawal of Egyptian armies from the battlefield, they reported in the journal Nature Communications.

Up to now, researchers had struggled to find an explanation for these events.

“Volcanic eruptions may have had a central role in the eventual collapse of the Ptolemaic dynasty,” the journal noted in a summary.

The findings, the authors said, also highlight the risk today of climate engineering schemes that would combat global warming by injecting billions of tiny particles into the stratosphere — just like a volcano — to block some of the sun’s rays.

Even if so-called solar radiation management lowers the planet’s temperature a notch or two, it could inadvertently cause major disruptions in rainfall patterns.

“Ptolemaic vulnerability to volcanic eruptions offers a caution for all monsoon-dependent agriculture regions,” which today include 70 percent of the world’s population, the authors wrote.

The Ptolemaic empire began in 305 BC shortly after the death of Alexander the Great and ended in 30 BC with the suicide of Cleopatra. After that, the region became a Roman province.

The kingdom mostly thrived, nourished by the silt-rich Nile overflowing its banks in summer across a far-flung network of grain fields. An ingenious system of channels and dams stored water after the river receded in September.

Violent uprisings

“When the flood was good, the Nile Valley was one of the most agriculturally productive places in the ancient world,” said Francis Ludlow, a climate historian at Trinity College Dublin and co-author of the study.

But in some years, the river failed to rise, and trouble followed. Why this happened was not known.

Drawing from climate models, Greenland ice cores, and ancient Egyptian writings, researchers led by Joseph Manning of Yale University pieced together a narrative that showed an unmistakable link with major volcanic eruptions around the world.

In 245 BC, for example, the ruler Ptolemy III suddenly, and inexplicably, abandoned a successful military campaign against his arch nemesis, the Seleucid Empire, centred in present-day Syria and Iraq.

“This about-face changed everything about Near-East history,” Manning said.

Historical records also pointed to simultaneous food shortages due to insufficient flooding of the Nile, as well as violent uprisings in the Ptolemaic Kingdom, which stretched across northeast Africa and parts of the Middle East.

A similar confluence of social upheaval, disease and starvation struck the empire in its final two decades.

Both periods of turmoil, the researchers found, coincided with major volcanic eruptions.

From more recent records, scientists know that the tens of millions of tonnes of sulphur dioxide particles ejected into the upper atmosphere by a major eruption can prevent monsoon weather from moving far enough north of the equator to thoroughly soak the Ethiopian highlands, the headwaters of the Nile.

This happened in 939 when Eldgja, in Iceland, blew its top, and again in 1783-84, when Iceland’s Laki erupted.

The Islamic Nilometer, a log of Nile water levels since 622, showed a corresponding impact on the river.

“The volcanic eruptions didn’t cause these (social) upheavals on their own,” Ludlow said.

“But they likely added fuel to existing economic, political and ethnic tensions.”

AFP