Thursday, May 28, 2020

The death marker protein cleans up your muscles after exercise

Researchers at the University of Copenhagen's Department of Nutrition, Exercise and Sports have demonstrated that physical activity prompts a clean-up of muscles as the protein Ubiquitin tags onto worn-out proteins, causing them to be degraded

FACULTY OF SCIENCE - UNIVERSITY OF COPENHAGEN

IMAGE: A SINGLE, INTENSE 10-MINUTE BICYCLE RIDE PROMPTS A CLEAN-UP OF MUSCLES AS THE PROTEIN UBIQUITIN TAGS ONTO WORN-OUT PROTEINS, CAUSING THEM TO BE DEGRADED. THIS PREVENTS THE ACCUMULATION OF DAMAGED... view more

CREDIT: PHOTO: CHRIS AND SIMON BRANFORD.

Physical activity benefits health in many ways, including the building and maintenance of healthy muscles, which are important for our ability to move about normally, as well as to fulfill the vital role of regulating metabolism. As most of the carbohydrate that we eat is stored in muscle, our muscles are extremely important for regulating metabolism.

An intense bike ride boosts Ubiquitin activity

Maintaining muscular function is essential. Part of our ability to do so depends upon proteins - the building blocks of muscles - being degraded when worn-out and eliminated in a kind of clean up process that allows them to be replaced by freshly synthesized proteins.

Now, Danish researchers - in collaboration with research colleagues at the University of Sydney, Australia - have demonstrated that a single, intense, roughly 10-minute bicycle ride results in a significant increase in the activity of Ubiquitin, the 'death marker protein' and a subsequent intensification of the targeting and removal of worn-out proteins in muscles. This paves the way for an eventual build-up of new proteins:

"Muscles eliminate worn-out proteins in several ways," explains Professor Erik Richter of the Section for Molecular Physiology at UCPH's Department of Nutrition, Exercise and Sports. He continues:

"One of these methods is when Ubiquitin, "the death-marker", tags a protein in question. Ubiquitin itself is a small protein. It attaches itself to the amino acid Lysine on worn-out proteins, after which the protein is transported to a Proteasome, which is a structure that gobbles up proteins and spits them out as amino acids. These amino acids can then be reused in the synthesis of new proteins. As such, Ubiquitin contributes to a very sustainable circulation of the body's proteins."

Why physical activity is healthy

While extensive knowledge has been accumulated about how muscles regulate the build-up of new proteins during physical training, much less is known about how muscle contractions and exercise serve to significantly clean-up worn-out proteins. According to Professor Bente Kiens, another project participant: "The important role of Ubiquitin for 'cleaning-up' worn-out proteins in connection with muscular activity was not fully appreciated. Now we know that physical activity increases Ubiquitin tagging on worn-out proteins."

Professor Jørgen Wojtaszewski, a third Danish project participant, explains that their findings serve to strengthen the entire foundation for the effect of physical activity: "Basically, it explains part of the reason why physical activity is healthy. The beauty is that muscle use, in and of itself , is what initiates the processes that keep muscles 'up to date', healthy and functional."

There remains a great amount of knowledge that would be interesting to delve deeper into, as very little is known about how different training regimens, gender, diet and genetic background impact the process and thus, the possibility of influencing optimal muscle function.

PSA screening: Benefit does not outweigh harm

Some men benefit from an earlier cancer diagnosis; however, more men are at risk of overdiagnosis and treatment-related complications; studies have yet to show whether a risk-adapted approach will affect this conclusion

INSTITUTE FOR QUALITY AND EFFICIENCY IN HEALTH CARE

The benefit of population-based PSA screening for men with an average risk of prostate cancer does not outweigh the harm caused. This is the conclusion drawn by the Institute for Quality and Efficiency in Health Care (IQWiG) in its final report after evaluating the worldwide evidence from studies on the topic. While screening using a PSA test benefits some men by preventing or delaying metastatic prostate cancer, at the same time, however, considerably more men are at risk to become permanently incontinent or impotent due to overdiagnosis and subsequent overtreatment - and this at a relatively young age.

At the hearing on the preliminary report, IQWiG discussed in detail with participants whether and how the harm from PSA screening could be reduced using risk-adapted screening strategies without simultaneously reducing the benefit. IQWiG's Director Jürgen Windeler emphasizes "Measures such as restricting biopsies to men at high risk of progression or using new biopsy methods are promising approaches to improve the benefit-harm ratio of PSA screening in the long term. However, there are currently no studies to prove this." Therefore, the overall assessment of PSA screening remained unchanged in IQWiG's final report.

The most common type of cancer in men

Prostate cancer is the most common cancer in men in Germany, accounting for 23 percent of all new cancer cases and causing approximately 14,000 deaths per year.

The aim of screening is to detect prostate cancer with a high risk of progression at an early stage in order to cure the disease. Two screening tests are currently used: the digital-rectal examination and the test for prostate-specific antigen (PSA). The former is part of the screening programme offered by statutory health insurance for men aged 45 and older, the PSA test is not.

The IQWiG benefit assessment now available is based on the analysis of 11 randomized controlled trials with more than 400,000 participants worldwide. All of these studies compare prostate cancer screening using the PSA test with no screening for prostate cancer.

More harm than benefit in the overall balance

After evaluating the evidence, IQWiG concludes that prostate cancer screening using a PSA test benefits some men with prostate cancer by delaying or preventing metastatic cancer. This advantage only occurs after several years. Moreover, it is unclear whether screening leads to an increase in overall life expectancy in these men.

At the same time, PSA screening harms overdiagnosed men (men with prostate cancer not requiring treatment) and men with a false-positive screening test result (men without prostate cancer). The overdiagnosed men are at risk of treatment-related complications such as incontinence and impotence. Men with a false-positive result may experience harm in the form of a worrying test result that is followed by a prostate biopsy.

Overall, prostate cancer screening using a PSA test harms considerably more men through overdiagnosis than it benefits men through earlier diagnosis of the cancer. In summary, on the basis of the available studies IQWiG therefore concludes that the benefit of PSA screening does not outweigh the harm. The Institute is in good company with this careful consideration: worldwide, almost all national health authorities and professional societies recommend against population-based PSA screening.

Tuesday, May 26, 2020

Eating more fibre can improve life expectancy

Eating more fibre can improve life expectancy for those with diabetes, Otago researchers say.

Type 2 diabetes has reached epidemic proportions worldwide, is associated with serious medical complications, and increases the risk of dying from COVID-19.

Two recent studies from University of Otago researchers have shown eating more dietary fibre improves life expectancy, although food processing may remove these benefits.

One study, a review published in Plos Medicine, used data collected from 8300 adults with type 1 or type 2 diabetes to show that those with a higher fibre intake faced a significant reduction in premature mortality compared to those eating the least fibre.

Lead author Dr Andrew Reynolds, National Heart Foundation Fellow of the Department of Medicine, says compared with the New Zealand average of 19 grams of fibre per day, those consuming 35g per day have a 35 per cent reduced risk of dying early.

His advice to increase fibre intakes by eating more whole grains, legumes, vegetables, and whole fruit applies to people across the globe, Dr Reynolds says.

"Try a few different ways to increase your fibre intake, see what works best for you.

"If you eat white refined bread or rolls, try changing to wholegrain bread or rolls. Try brown rice, try brown pasta, try adding half a tin of legumes to meals you already make.

"Try an extra veggie with your main meal -- fresh, frozen, or canned without sodium are all good choices."

The research team also analysed 42 trials with 1789 participants where adults with prediabetes, type 1 or type 2 diabetes were given more fibre and whole grains for at least six weeks.

They found consistent improvements in blood glucose control, cholesterol levels and reductions in body weight when adults with prediabetes, type 1 or type 2 diabetes increased their fibre or wholegrain intake.

Senior author Professor Jim Mann, from the Department of Medicine and Director of the Healthier Lives National Science Challenge, has been involved in diabetes research for over 40 years and led the first controlled trials of high fibre diets in diabetes in the 1970s.

"When our controlled studies confirmed the benefits of dietary fibre four decades ago, we never suspected that they would be quite so impressive," he says.

"It has taken forty years of research and these meta analyses to be able to show that this dietary treatment can have an effect as striking as that produced by medications."

In the second study, researchers found not all foods that contain fibre are created equal -- while whole grains are an important source of fibre, their benefits may be diluted when heavily processed.

For this study, to be published in Diabetes Care, Dr Reynolds and Professor Mann led a trial in adults with type 2 diabetes living in Dunedin to consider the effects of food processing on the health benefits of whole grains.

Participants ate minimally-processed wholegrain foods such as wholegrain oats and chunky grainy bread for one fortnight, then more processed wholegrain foods such as instant oats and wholemeal bread for another fortnight.

"Wholegrain foods are now widely perceived to be beneficial, but increasingly products available on the supermarket shelves are ultra-processed," says Professor Mann.

Researchers used cutting edge glucose monitors to record participant blood glucose levels over the day and night during the two-week intervention periods.

Results showed improved blood glucose levels after meals and reduced variability of blood glucose levels throughout the day when participants consumed the minimally processed whole grains.

The results were most striking after breakfast, as that was when most of the whole grains were consumed.

Researchers also observed something unexpected.

Although participants were asked not to lose weight by eating less during the trial, results showed their average weight increased slightly after two weeks of eating processed whole grains, and decreased slightly after eating minimally processed whole grains.

These two studies, along with previous research, confirm choosing high fibre foods like whole grains, whole fruit, dark leafy greens or legumes is good for everyone, and important in managing diseases such as type 1 or type 2 diabetes, Dr Reynolds says.

"However we are now beginning to understand that how foods are processed is also important, and for whole grains when you finely mill them you can remove their benefits," he concludes.

Friday, May 22, 2020

Social isolation increases the risk of heart attacks, strokes, and death from all causes

Those who are socially isolated are over 40% more likely to have a cardiovascular event, such as a heart attack or stroke, than those who were socially integrated, new research has shown

SPINK HEALTH

(Vienna, Friday, 22 May, 2020) Those who are socially isolated are over 40% more likely to have a cardiovascular event, such as a heart attack or stroke, than those who were socially integrated, new research has shown.

The German study, due to presented tomorrow at the European Academy of Neurology (EAN) Virtual Congress, found that those who are socially isolated are almost 50% more likely to die from any cause. The research also showed that a lack of financial support independently increased the risk of cardiovascular events.

Performed within the Heinz Nixdorf Recall study (HNR) and led by Dr Janine Gronewold and Prof Dirk M. Hermann from the University Hospital in Essen, Germany, the research analysed data from 4,316 individuals (average age 59.1 years) who were recruited into the large community-based study between 2000 and 2003.

The study participants entered the study with no known cardiovascular disease and they were followed for an average of 13 years. At the start of the study, information was collected on different types of social support, with social integration assessed based on marital status and cohabitation, contact with close friends and family, and membership of political, religious, community, sports or professional organisations.

"We have known for some time that feeling lonely or lacking contact with close friends and family can have an impact on your physical health", commented Dr Gronewold. "What this study tells us is that having strong social relationships is of high importance for your heart health and similar to the role of classical protective factors such as having a healthy blood pressure, acceptable cholesterol levels, and a normal weight."

Professor Jöckel, one of the PI's of the HNR added, "This observation is of particular interest in the present discussion on the COVID-19 pandemia, where social contacts are or have been relevantly restricted in most societies."

During the 13.4 years of follow-up, 339 cardiovascular events such as heart attacks or strokes occurred, and there were 530 deaths among the study participants. After adjusting for (removing the influence of) other factors that might have contributed to these events and deaths (for example, standard cardiovascular risk factors), a lack of social integration was found to increase the future risk of cardiovascular events by 44% and to increase the risk of death from all causes by 47%, A lack of financial support was associated with a 30% increased risk of cardiovascular events.

"We don't understand yet why people who are socially isolated have such poor health outcomes, but this is obviously a worrying finding, particularly during these times of prolonged social distancing," said Dr Gronewold. "What we do know is that we need to take this seriously, work out how social relationships affect our health, and find effective ways of tackling the problems associated with social isolation to improve our overall health and longevity," said Prof Hermann.

Lowering blood pressure reduces risk of developing dementia F

Research completed in NUI Galway has shown that lowering blood pressure by taking blood pressure medications reduces the risk of developing dementia and cognitive impairment by 7%. The findings are published today in a leading international medical journal, the Journal of the American Medical Association (JAMA).

Fourteen randomised controlled trials (96,158 participants) were included in this systematic review and meta-analysis. Blood pressure lowering with antihypertensive medications reduced the risk of developing dementia or cognitive impairment by 7%, and cognitive decline also by 7% over a four-year period.

"When you consider how common dementia is in the population (50 million people worldwide), effective treatment and control of hypertension would have a major impact on preventing dementia. Our findings emphasize the need for more effective screening, prevention, and treatment of hypertension, which remains suboptimal in Ireland", explains Dr Conor Judge, joint first author and Wellcome Trust Health Research Board Irish Clinical Academic Training (ICAT) fellow.

Dr Judge continued: "We know from The Irish Longitudinal Study on Aging that two thirds of people aged over 50 in Ireland have hypertension (high blood pressure), of which half are unaware of the diagnosis, and one third are not on treatment. This is a major care gap."

This study aimed to gather all the evidence from previous trials of blood pressure lowering medications and estimate how much the risk of dementia can be reduced by taking blood pressure lowering medications in people who are diagnosed with high blood pressure. Blood pressure lowering reduces the risk of stroke and heart disease. Prevention of dementia can now be added to the benefits of treating hypertension. Importantly, there are no available therapies that directly prevent dementia, so this study highlights the critical importance of blood pressure in the risk of dementia.

Dr Michelle Canavan, Consultant Geriatrician at Galway University Hospital, and senior author of the paper, commented: "Prevention of dementia is a major health priority. We know from previous research that a major concern of older people is developing dementia. The message from this study is simple: Get your blood pressure checked. If it is high, it can be readily treated with lifestyle changes and medications. We would hope that our study will heighten awareness of the importance of controlling blood pressure to maintain "brain" health, combined with a healthy lifestyle."

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The research was funded by Wellcome Trust, HRB, HSE and NUI Galway through the ICAT programme.

Adding a blend of spices to a meal may help lower inflammation

Adding an array of spices to your meal is a surefire way to make it more tasty, but new Penn State research suggests it may increase its health benefits, as well.

In a randomized, controlled feeding study, the researchers found that when participants ate a meal high in fat and carbohydrates with six grams of a spice blend added, the participants had lower inflammation markers compared to when they ate a meal with less or no spices.

"If spices are palatable to you, they might be a way to make a high-fat or high-carb meal more healthful," said Connie Rogers, associate professor of nutritional sciences. "We can't say from this study if it was one spice in particular, but this specific blend seemed to be beneficial."

The researchers used a blend of basil, bay leaf, black pepper, cinnamon, coriander, cumin, ginger, oregano, parsley, red pepper, rosemary, thyme and turmeric for the study, which was recently published in the Journal of Nutrition.

According to Rogers, previous research has linked a variety of different spices, like ginger and tumeric, with anti-inflammatory properties. Additionally, chronic inflammation has previously been associated with poor health outcomes like cancer, cardiovascular disease, and overweight and obesity, which affects approximately 72 percent of the U.S. population.

In more recent years, researchers have found that inflammation can spike after a person eats a meal high in fat or sugar. While it is not clear whether these short bursts -- called acute inflammation -- can cause chronic inflammation, Rogers said it's suspected they play a factor, especially in people with overweight or obesity.

"Ultimately the gold standard would be to get people eating more healthfully and to lose weight and exercise, but those behavioral changes are difficult and take time," Rogers said. "So in the interim, we wanted to explore whether a combination of spices that people are already familiar with and could fit in a single meal could have a positive effect."

For the study, the researchers recruited 12 men between the ages of 40 and 65, with overweight or obesity, and at least one risk factor for cardiovascular disease. Rogers said the sample was chosen because people in these demographics tend to be at a higher risk for developing poorer health outcomes.

In random order, each participant ate three versions of a meal high in saturated fat and carbohydrates on three separate days: one with no spices, one with two grams of the spice blend, and one with six grams of the spice blend. The researchers drew blood samples before and then after each meal hourly for four hours to measure inflammatory markers.

"Additionally, we cultured the white blood cells and stimulated them to get the cells to respond to an inflammatory stimulus, similar to what would happen while your body is fighting an infection," Rogers said. "We think that's important because it's representative of what would happen in the body. Cells would encounter a pathogen and produce inflammatory cytokines."

After analyzing the data, the researchers found that inflammatory cytokines were reduced following the meal containing six grams of spices compared to the meal containing two grams of spices or no spices. Rogers said six grams roughly translates to between one teaspoon to one tablespoon, depending on how the spices are dehydrated.

While the researchers can't be sure which spice or spices are contributing to the effect, or the precise mechanism in which the effect is created, Rogers said the results suggest that the spices have anti-inflammatory properties that help offset inflammation caused by the high-carb and high-fat meal.

Additionally, Rogers said that a second study using the same subjects, conducted by Penn State researchers Penny Kris-Etherton and Kristina Petersen, found that six grams of spices resulted in a smaller post-meal reduction of "flow mediated dilation" in the blood vessels -- a measure of blood vessel flexibility and marker of blood vessel health.

In the future, Rogers said she, Kris-Etherton and Petersen will be working on further studies to determine the affects of spices in the diet across longer periods of time and within a more diverse population.

Eating fish reduces risk of cardiovascular disease

A diet rich in fish or omega 3 modulates the concentration of lipids that are passed on to cells by lipoproteins and reduces the likelihood of atherosclerosis.

UNIVERSITAT ROVIRA I VIRGILI

A study by researchers from the Universitat Rovira i Virgili (URV) and Harvard Medical School has found that consuming omega 3 primarily through fish, but also in supplements containing these fatty acids, can modulate lipoproteins, that is, the particles that transport lipids through the blood, and can reduce the risk of cardiovascular disease. The association between the consumption of omega 3 and the reduction in the risk of suffering cardiovascular events has been demonstrated through the analysis of lipoprotein samples from 26,034 women, the largest and most detailed study ever carried out. The study is particularly important because cardiovascular disease is the most prevalent cause of death, with 1 in 3 people dying from cardiovascular events.

The research has been led by Núria Amigó, CEO of the URV spin off Biosfer Teslab and member of the Metabolomics Interdisciplinary Laboratory (MIL@b) - Metabolomics Platform, which was jointly created by the URV and the CIBERDEM and which is part of the Pere Virgili Health research Institute. Xavier Correig, professor from the Department of Electronic, Electrical and Automatic Engineering and director of the MIL@b - Metabolomics Platform, has participated in the study together with researchers from the Center for Lipid Metabolomics, Division of Preventive Medicine at the Brigham and Women's Hospital (Harvard Medical School) headed by Samia Mora.

Up to now it had been shown that a high consumption of omega 3 fatty acids was associated with lower levels of triglycerides in the blood. However, it had also been related to an increase in LDL cholesterol, that is, low-density cholesterol transported by lipoproteins, also known as bad cholesterol. LDL cholesterol increases the risk of cardiovascular diseases because it can accelerate the formation of atherosclerosis, that is, the process by which the arteries harden and lose their elasticity.

However, the study has found that increased consumption of LDL cholesterol from fish is associated principally with the cholesterol transported by the largest LDL particles, which are less atherogenic, and not with an increase in the total number of LDL particles. This decrease in the number of triglycerides transported by any type of lipoprotein helps protect the individual from heart disease.

The 3 types of omega 3 fatty acids studied, namely α-linoleic acid (ALA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are present in fish and other foods and are essential to human physiology, and the study has found that they differ in their association with the risk of cardiovascular disease. It found that there was no increase in the smallest LDL lipoproteins that transport cholesterol; instead the increase was among the largest LDL lipoproteins, which are not associated with the risk of heart disease. There was a decrease in all of the triglyceride-transporting particles and, moreover, the average size of the HDL and LDL particles increased, a phenomenon that is associated with increased protection from cardiovascular illness.

These conclusions have been obtained through mathematical modelling of the consumption of fish and omega 3 (both as a whole and of the different types ALA, DHA and EPA) and the profile of lipoproteins. The results were obtained by Nuclear Magnetic Resonance, "which can go further than simply analysing triglyceride and cholesterol content and can quantify the number and size of the different subtypes of plasmatic lipoprotein", explained Núria Amigó. She described how among the LDL particles that transport cholesterol "it is the smallest that are associated with a future cardiovascular event".

Another important element of the study is that the mathematical models used to evaluate the association between the consumption of fish and the reduction in cardiovascular risk have isolated other nutritional factors that affect the result, such as the consumption of other foods, the concentration of omega 3 according to the origin of the fish (wild or farmed) and traditional risk factors such as a sedentary lifestyle, age, body mass index and smoking.

The study analysed a cohort from the Women's Health Study by the Brigham and Women's Hospital, affiliated to Harvard Medical School, and involved the use of Nuclear Magnetic Resonance to characterise the plasma of 26,034 women with an average age of 53 (most were between 48 and 59).

Having confirmed that the risk factor associated with lipids, cholesterol concentration, triglycerides and the different subtypes of particles is modulated by the consumption of omega 3 fatty acids, "we now need to find out if the consumption of fish is associated with lower mortality from both cardiovascular diseases and other causes", Amigó explained, because "although the risk is lower in terms of lipids, we need to look at other pro-inflammatory factors and questions such as exposure to heavy metals".

Wednesday, May 20, 2020

Our mental health and mortality have a strong correlation with the amount of autonomy we have at our job

As millions continue working from home during the pandemic or are required to report to jobs as essential employees, many have raised questions about how these work conditions impact our health -- and not just as they relate to COVID-19.

A new study from the Indiana University Kelley School of Business finds that our mental health and mortality have a strong correlation with the amount of autonomy we have at our job, our workload and job demands, and our cognitive ability to deal with those demands.

"When job demands are greater than the control afforded by the job or an individual's ability to deal with those demands, there is a deterioration of their mental health and, accordingly, an increased likelihood of death," said Erik Gonzalez-Mulé, assistant professor of organizational behavior and human resources at the Kelley School and the paper's lead author.

"We examined how job control -- or the amount of autonomy employees have at work -- and cognitive ability -- or people's ability to learn and solve problems -- influence how work stressors such as time pressure or workload affect mental and physical health and, ultimately, death," he said. "We found that work stressors are more likely to cause depression and death as a result of jobs in which workers have little control or for people with lower cognitive ability."

On the other hand, Gonzalez-Mulé and his co-author, Bethany Cockburn, assistant professor of management at Northern Illinois University, found that job demands resulted in better physical health and lower likelihood of death when paired with more control of work responsibilities.

"We believe that this is because job control and cognitive ability act as resources that help people cope with work stressors," Gonzalez-Mulé said. "Job control allows people to set their own schedules and prioritize work in a way that helps them achieve their work goals, while people that are smarter are better able to adapt to the demands of a stressful job and figure out ways to deal with stress."

The study, "This Job Is (Literally) Killing Me: A Moderated-Mediated Model Linking Work Characteristics to Mortality," appears in the current issue of the Journal of Applied Psychology. It is a follow-up to previous research the pair published in 2017, which was the first study in the management and applied psychology fields to examine the relationship between job characteristics and mortality.

The researchers used data from 3,148 Wisconsin residents who participated in the nationally representative, longitudinal Midlife in the United States survey. Of those in their sample, 211 participants died during the 20-year study.

"Managers should provide employees working in demanding jobs more control, and in jobs where it is unfeasible to do so, a commensurate reduction in demands. For example, allowing employees to set their own goals or decide how to do their work, or reducing employees' work hours, could improve health," Gonzalez-Mulé said. "Organizations should select people high on cognitive ability for demanding jobs. By doing this, they will benefit from the increased job performance associated with more intelligent employees, while having a healthier workforce.

"COVID-19 might be causing more mental health issues, so it's particularly important that work not exacerbate those problems," Gonzalez-Mulé said. "This includes managing and perhaps reducing employee demands, being aware of employees' cognitive capability to handle demands and providing employees with autonomy are even more important than before the pandemic began.

Tuesday, May 19, 2020

Six feet not far enough to stop virus transmission in light winds

Current social distancing guidelines of 6 feet may be insufficient, because a mild cough occurring in low wind speeds of 4-15 kph can propel saliva droplets 18 feet

AMERICAN INSTITUTE OF PHYSICS

IMAGE: SALIVA DROPLETS CAN TRAVEL LARGE DISTANCES, DEPENDING ON ENVIRONMENTAL CONDITIONS SUCH AS WIND SPEED, TEMPERATURE, PRESSURE AND HUMIDITY. WIND SHOWN BLOWING LEFT TO RIGHT AT SPEEDS OF 4 KPH (TOP)... view more

CREDIT: IMAGE COURTESY OF THE AUTHORS

WASHINGTON, May 19, 2020 -- Airborne transmission of viruses, like the virus causing COVID-19, is not well understood, but a good baseline for study is a deeper understanding of how particles travel through the air when people cough.

In a paper published in Physics of Fluids, from AIP Publishing, Talib Dbouk and Dimitris Drikakis discovered that with even a slight breeze of 4 kph, saliva travels 18 feet in 5 seconds.

"The droplet cloud will affect both adults and children of different heights," Drikakis said. "Shorter adults and children could be at higher risk if they are located within the trajectory of the traveling saliva droplets."

Saliva is a complex fluid, and it travels suspended in a bulk of surrounding air released by a cough. Many factors affect how saliva droplets travel, including the size and number of droplets, how they interact with one another and the surrounding air as they disperse and evaporate, how heat and mass are transferred, and the humidity and temperature of the surrounding air.

To study how saliva moves through air, Dbouk and Drikakis created a computational fluid dynamics simulation that examines the state of every saliva droplet moving through the air in front of a coughing person. Their simulation considered the effects of humidity, dispersion force, interactions of molecules of saliva and air, and how the droplets change from liquid to vapor and evaporate.

The computational domain in the simulation is a grid representing the space in front of a coughing person. The analysis involved running partial differential equations on 1,008 saliva droplets and solving approximately 3.7 million equations in total.

"Each cell holds information about variables like pressure, fluid velocity, temperature, droplet mass, droplet position, etc.," Dbouk said. "The purpose of the mathematical modeling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves."

Further studies are needed to determine the effect of ground surface temperature on the behavior of saliva in air and to examine indoor environments, where air conditioning significantly affects the particle movement through air.

"This work is vital, because it concerns health and safety distance guidelines, advances the understanding of spreading and transmission of airborne diseases, and helps form precautionary measures based on scientific results," said Drikakis.

Coffee linked to lower body fat in women

Compounds in coffee may have anti-obesity properties

Women who drink two or three cups of coffee a day have been found to have lower total body and abdominal fat than those who drink less, according to a new study published in The Journal of Nutrition.

Researchers examined data from the National Health and Nutrition Examination Survey, organised by the Center for Disease Control (CDC) in the United States and looked at the relationship between cups of coffee drunk per day, and both total body fat percentage and abdominal or 'trunk' fat (adiposity).

They found that women aged 20-44 who drank two or three cups of coffee per day had the lowest levels of adiposity, 3.4% lower than people who did not consume coffee. Among women aged between 45-69, those who drank four or more cups had an adiposity percentage 4.1% lower.

Overall, the average total body fat percentage was 2.8% lower among women of all ages who drank two or three cups of coffee per day.

The findings were consistent whether the coffee consumed was caffeinated or decaffeinated, and among smokers/non-smokers and those suffering from chronic diseases when compared to those in good health.

In men, the relationship was less significant, although men aged 20-44 who drank two or three cups per day had 1.3% less total fat and 1.8% less trunk fat than those who did not consume coffee.

Around 7 million tons of coffee is consumed globally every year.

Dr Lee Smith, Reader in Public Health at Anglia Ruskin University and senior author of the study, said: "Our research suggests that there may be bioactive compounds in coffee other than caffeine that regulate weight and which could potentially be used as anti-obesity compounds.

"It could be that coffee, or its effective ingredients, could be integrated into a healthy diet strategy to reduce the burden of chronic conditions related to the obesity epidemic.

"It is important to interpret the findings of this study in light of its limitations -- the study was at a specific point in time so trends cannot be established. However, we don't believe that someone's weight is likely to influence their coffee consumption."

Antiviral drug can speed up recovery of COVID-19 patients

An international team of researchers led by Dr. Eleanor Fish, emerita scientist at the Toronto General Hospital Research Institute, University Health Network, and professor in the University of Toronto's Department of Immunology, has shown for the first time that an antiviral drug can help speed up the recovery of COVID-19 patients.

According to the new study, published today in Frontiers in Immunology, treatment with interferon(IFN)-α2b may significantly accelerate virus clearance and reduce levels of inflammatory proteins in COVID-19 patients.

The research team found that treatment with this drug, which has been used clinically for many years, significantly reduced the duration of detectable virus in the upper respiratory tract, on average by about 7 days. It also reduced blood levels of interleukin(IL)-6 and C-reactive protein (CRP), two inflammatory proteins found in COVID-19 patients.

Dr. Fish says that the research team considered IFN-α therapy for COVID-19 after they demonstrated interferon provided therapeutic benefit during the SARS outbreak of 2002 and 2003.

"Rather than developing a virus-specific antiviral for each new virus outbreak, I would argue that we should consider interferons as the 'first responders' in terms of treatment," says Dr. Fish.

"Interferons have been approved for clinical use for many years, so the strategy would be to 'repurpose' them for severe acute virus infections."

Boosting a natural defense mechanism

Interferons are a group of signaling proteins released by the human body in response to all viruses. As Dr. Fish explains, they are a "first line of defense."

They target different stages of a virus's life cycle, inhibiting them from multiplying. They also boost an immune response by activating different immune cells to clear an infection. Some viruses, however, can block this natural defense mechanism.

"But it is possible to override this block. If a virus blocks interferon production, then treating with interferon can offset this."

Study details

The researchers conducted this exploratory study on a group of 77 patients with COVID-19 in Wuhan, China. These patients were admitted to Union Hospital, Tongii Medical College, between January 16 and February 20, 2020. They represented moderate cases of the disease as none of the patients required intensive care or prolonged oxygen supplementation or intubation.

Despite the study's limitations of a small, non-randomized group of patients, the work provides several important and novel insights into COVID-19 disease, notably that treatment with IFN-α2b can accelerate viral clearance from the upper respiratory tract and also reduce circulating levels of inflammatory factors that are associated with severe COVID-19.

Dr. Fish says a randomized clinical trial is a crucial next step. According to her, a clinical trial with a larger group of infected patients who are randomized to treatment or placebo would further this research.

In the meantime, the findings from this study are the first to suggest therapeutic efficacy of IFN-α2b as an available antiviral intervention for COVID-19, which may also benefit public health measures by shortening the duration of viral clearance and therefore slowing the tide of the pandemic.

Further evidence does not support hydroxychloroquine for patients with COVID-19

The anti-inflammatory drug hydroxychloroquine does not significantly reduce admission to intensive care or death in patients hospitalised with pneumonia due to covid-19, finds a study from France published by The BMJ today.

A randomised clinical trial from China also published today shows that hospitalised patients with mild to moderate persistent covid-19 who received hydroxychloroquine did not clear the virus more quickly than those receiving standard care. Adverse events were higher in those who received hydroxychloroquine.

Taken together, the results do not support routine use of hydroxychloroquine for patients with covid-19.

Hydroxychloroquine can reduce inflammation, pain, and swelling, and is widely used to treat rheumatic diseases. It is also used as an anti-malarial drug. Lab tests showed promising results, but accumulating trial and observational evidence has called into question whether there are any meaningful clinical benefits for patients with covid-19.

Despite this, hydroxychloroquine has already been included in Chinese guidelines on how best to manage the disease, and the US Food and Drug Administration (FDA) issued an emergency use authorization to allow the drug to be provided to certain hospitalized patients. The FDA has since warned against use outside clinical trials or hospital settings due to the risk of heart rhythm problems.

In the first study, researchers in France assessed the effectiveness and safety of hydroxychloroquine compared with standard care in adults admitted to hospital with pneumonia due to covid-19 who needed oxygen.

Of 181 patients, 84 received hydroxychloroquine within 48 hours of admission and 97 did not (control group).

They found no meaningful differences between the groups for transfer to intensive care, death within 7 days, or developing acute respiratory distress syndrome within 10 days.

The researchers say that caution is needed in the interpretation of their results, but that their findings do not support the use of hydroxychloroquine in patients hospitalised with covid-19 pneumonia.

In the second study, researchers in China assessed the effectiveness and safety of hydroxychloroquine compared with standard care in 150 adults hospitalised with mainly mild or moderate covid-19.

Patients were randomly split into two groups. Half received hydroxychloroquine in addition to standard care and the others received standard care only (control group).

By day 28, tests revealed similar rates of covid-19 in the two groups but adverse events were more common in those who received hydroxychloroquine. Symptom alleviation and time to relief of symptoms also did not differ meaningfully between the two groups.

While further work is needed to confirm these results, the authors say that their findings do not support the use of hydroxychloroquine to treat patients with persistent mild to moderate covid-19.

Health News Report