Tuesday, November 17, 2020

Could key gene system discovery be suffocating corals' last gasp?

Ocean deoxygenation is now being recognised as major threat to future global coral reef survival

UNIVERSITY OF TECHNOLOGY SYDNEY

Research News

IMAGE

IMAGE: A UNIQUE STRESS EXPERIMENT ALIGNED DEOXYGENATION STRESS TO THE NATURAL NIGHT-DAY CYCLE OF COMMON REEF-BUILDING CORALS FROM THE GREAT BARRIER REEF. view more 

CREDIT: MORGAN BENNETT-SMITH

Oxygen is life, in or out of the water, raising concerns that declining ocean oxygen stores are adding an additional environmental stress to already highly vulnerable coral reef ecosystems. While the twin effects of ocean warming and acidification are well studied, until now there has been limited understanding of how the growing threat of ocean deoxygenation may impact the ability of corals to function and ultimately form reefs.

A unique deoxygenation-reoxygenation stress experiment has given researchers from the University of Technology Sydney (UTS), University of Konstanz and University of Copenhagen insight into how corals manage deoxygenation stress and the key genes that likely drive varied stress susceptibility that commonly results in coral bleaching.

The study, published in Global Change Biology discovered that, like other animals and humans, corals have a similar, sophisticated response to low oxygen levels, or hypoxia. The response is commonly activated during oxygen-deprived exercise and cancer growth in humans

"Ocean deoxygenation is potentially a greater and more immediate threat to coral reef survival than ocean warming and acidification." lead author and UTS PhD candidate in the Rachel Alderdice said.

"Coral reefs are increasingly being exposed to low oxygen events due to climate change and localised pollution often caused by nutrient run-off.

"The extent to which corals are at risk from future declines in background ocean oxygen levels relies on their hypoxia detection and response systems so to be able to identify this gene response system is significant and exciting," Ms Alderdice, from the UTS Climate Change Cluster(C3) Future Reefs Research Programme, said.

The unique stress experiment aligned deoxygenation stress to the natural night-day cycle of common reef-building corals from The Great Barrier Reef. Transcriptomic RNA sequencing revealed the key genes expressed that help keystone species such as Acropora tenuis respond to, and tolerate, low oxygen levels.

However the research also revealed that not all the coral appeared to be equally sensitive to hypoxia.

"We found those corals that bleached had a delayed, less-effective programming of their hypoxia response gene system compared to the non-bleached coral. The differences in programming abilities for this key gene system may be fundamental to understanding what dictates corals' capacity to tolerate environmental stress - and ultimately how to more accurately predict the future for coral reefs," University of Konstanz, and senior author, Dr Christian Voolstra said

The researchers say that the identification of such 'common switch' gene repertoires to stress might provide a novel means to identify genes of interest to guide novel diagnostics for improved reef coral management or as target for selective breeding 'reef restoration' efforts aimed at increasing coral stress resistance.

Co-author Associate Professor David Suggett, who leads the UTS C3 Future Reefs Research Program said "A fundamental concern we have right now is whether corals and reefs are already feeling the effects of sub-lethal O2 stress. We have been so preoccupied with unravelling the effects of ocean warming and acidification, we have forgotten deoxygenation, despite its life sustaining role and that oxygen is an ocean property we can measure well".

"This work confirms our recent analysis that continued ocean deoxygenation will play a critical role in shaping the future of our reefs, and yet another reason to urgently tackle climate change," he said.

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Permanent night shift workers at heightened risk of moderate to severe asthma

Public health implications 'far reaching' given prevalence of asthma and shift work, warn researchers

BMJ

Research News

Shift workers, especially those working permanent night shift rotas, may be at heightened risk of moderate to severe asthma, suggests research published online in the journal Thorax.

Given the prevalence of both shift work and asthma in industrialised nations, the public health implications of these findings are potentially "far-reaching," warn the researchers.

Around 1 in 5 employees in the developed world works permanent or rotating night shifts. Shift work causes a person's internal body clock (circadian rhythm) to be out of step with the external light and dark cycle.

This misalignment is associated with a heightened risk of various metabolic disorders, cardiovascular disease, and cancer.

Symptoms of asthma, such as wheeze and airway whistling, vary considerably, according to the time of day or night, and the researchers wanted to find out if shift work might also be associated with an increased risk of asthma and/or its severity.

They were also keen to explore how influential chronotype--individual body clock preference for morning ('lark') or evening ('owl') activity--and genetic predisposition to asthma might be.

They drew on medical, lifestyle, and employment information supplied between 2007 and 2010 by 286,825 participants in the UK Biobank.

All these participants were aged between 37 and 72, and either in paid employment or self-employed. Most (83%) worked regular office hours, while 17% worked shifts, around half of which (51%) included night shifts. Shift patterns comprised: never or occasional night shifts; irregular or rotating night shifts; and permanent night shifts.

Compared with those working office hours, shift workers were more likely to be men, smokers, and to live in urban areas and in more deprived neighbourhoods. They also drank less alcohol, slept fewer hours, and worked longer hours.

Night shift workers were more likely to be 'owls' and to have poorer health. And they were more likely to work in service jobs or as process, plant and machine operatives; those working office hours tended to be in administrative roles and to have professional jobs.

Some 14,238 (around 5%) of all the study participants had asthma; in 4783 (nearly 2%) symptoms were moderate to severe (based on their medications).

The researchers compared the effect of working office hours with shift work on asthma diagnosis, lung function, and symptoms of asthma.

After taking account of age and sex, and a wide range of other potentially influential risk factors, there was a 36% increase in the odds of having moderate to severe asthma in permanent night shift workers compared to those working normal office hours.

Similarly, the odds of wheeze or airway whistling were 11-18% higher among those working any of the three shift patterns, while the odds of poorer lung function were around 20% higher in shift workers who never or rarely worked nights and in those working permanent night shifts.

Those who were definitely either larks or owls, known as 'extreme chronotypes,' were significantly more likely to have asthma even after taking account of a range of potentially influential risk factors. And the odds of moderate to severe asthma were 55% higher among larks working irregular shifts, including nights.

But genetic susceptibility to asthma didn't affect the odds of developing asthma among those working shifts.

This is an observational study, so can't establish cause, say the researchers. "However, it is plausible that circadian misalignment leads to asthma development," they point out."

"Interestingly, chronotype does change with age, getting later through adolescence and then earlier as adults age, suggesting that older individuals might find it more difficult to adjust to night shift work than younger adults," they explain.

"The public health implications of our findings are potentially far-reaching, since both shift work and asthma are common in the industrialised world," they warn. Asthma affects 339 million people worldwide and costs health and care services more than £1billion in the UK alone.

"There are no specific national clinical guidelines for how to manage asthma in shift workers," they highlight, but adapting shift work schedules to suit individual chronotype might be a worthwhile public health measure that is worth exploring further, they suggest.

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Externally peer reviewed? Yes
Evidence type: Observational
Subjects: Shift workers

Looking inside the glass

INSTITUTE OF INDUSTRIAL SCIENCE, THE UNIVERSITY OF TOKYO

Research News

IMAGE

IMAGE: SCIENTISTS AT THE UNIVERSITY OF TOKYO STUDY ALUMINOSILICATE GLASS TO DETERMINE ITS COMPLEX LOCAL STRUCTURE WITH UNPRECEDENTED DETAIL. THIS WORK MAY LEAD TO TOUGHER AND MORE INEXPENSIVE GLASS FOR TOUCHSCREENS... view more 

CREDIT: INSTITUTE OF INDUSTRIAL SCIENCE, THE UNIVERSITY OF TOKYO

Tokyo, Japan - A team of researchers from the Institute of Industrial Science at The University of Tokyo used advanced electron spectroscopy and computer simulations to better understand the internal atomic structure of aluminosilicate glass. They found complex coordination networks among aluminum atoms within phase-separated regions. This work may open the possibility for improved glasses for smart device touchscreens.

As the demand for smartphones, tablets, and solar panels increases, so too will the need for more high-quality, tough, transparent glass. One of the candidate materials for these applications is called aluminosilicate glass, which is made of aluminum, silicon, and oxygen. As with all amorphous materials, the glass does not form a simple lattice but exists more like a disordered "frozen liquid." However, intricate structures can still form between that have not yet been analyzed by scientists.

Now, a team of researchers at The University of Tokyo have used electron energy loss fine structure spectroscopy with a scanning transmission electron microscope to reveal the local arrangement of atoms within a glass made of 50% aluminum oxide (Al2O3) and 50% silicon dioxide (SiO2). "We chose to study this system because it is known to phase separate into aluminum-rich and silicon-rich regions" first author Kun-Yen Liao says. When imaging with an electron microscope, some emitted electrons undergo inelastic scattering, which causes them to lose some of their original kinetic energy. The amount of energy dissipated varies based on the location and type of atom or cluster of atoms in the glass sample it hit. Electron loss spectroscopy is sensitive enough to tell the difference between aluminum coordinated in tetrahedral as opposed to octahedral clusters. By fitting the profile of the electron energy loss fine structure spectra pixel by pixel, the abundance of the various aluminum structures was determined with nanometer precision. The team also used computer simulations to interpret the data. "Aluminosilicate glasses can be manufactured to resist high temperatures and compressive stresses. This makes them useful for a wide range of industrial and consumer applications, such as touch displays, safety glass, and photovoltaics," senior author Teruyasu Mizoguchi says. Because aluminosilicate is also naturally occurring, this technique can also be used for geological research. The work is published in The Journal of Physical Chemistry Letters as "Revealing Spatial Distribution of Al Coordinated Species in a Phase-separated Aluminosilicate Glass by STEM-EELS".

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About Institute of Industrial Science (IIS), the University of Tokyo

Institute of Industrial Science (IIS), the University of Tokyo is one of the largest university-attached research institutes in Japan.

More than 120 research laboratories, each headed by a faculty member, comprise IIS, with more than 1,000 members including approximately 300 staff and 700 students actively engaged in education and research. Our activities cover almost all the areas of engineering disciplines. Since its foundation in 1949, IIS has worked to bridge the huge gaps that exist between academic disciplines and real-world applications.

Seafood mislabeling is having negative impacts on the marine environment

ADVANCED CONSERVATION STRATEGIES

Research News

Media outlets, governments, academics, and NGOs are increasingly recognizing and documenting seafood fraud. Policies are being designed and revamped in an attempt to reduce seafood mislabeling. And, more and more groups are testing products for mislabeling. Despite the increased attention, however, we still know very little about the consequences of seafood mislabeling. Evidence for negative impacts has been largely limited to hypotheses and anecdotes.

A new paper by Advanced Conservation Strategies and colleagues provides a system-level analysis to show that conditions exist for seafood mislabeling to lead to negative outcomes. They combined multiple data sources to characterize the mislabeling landscape for the entire US seafood supply. Doing so allowed them to estimate how much mislabeled seafood Americans are consuming every year. That statistic, known as mislabeled apparent consumption, turns out to be a lot: somewhere between 420-550 million pounds of seafood, which exceeds total seafood landings of all but three ports in the United States. That's more than a pound of mislabeled seafood for every American.

By compiling lots of different data and analyzing it in new ways, we demonstrated that mislabeling rates for seafood products are often quite lower than what is commonly reported. However, when those rates are combined with how much of those seafood products are consumed, Americans are likely eating quite a bit of mislabeled seafood, says Josh Donlan, who co-led the research.

Much of that mislabeled seafood comes from products that are swapped out for what Americans eat a lot of - like shrimp, salmon and, crab. The study also revealed the complex global nature of seafood mislabeling. Substitute products are more likely to be imported than the product listed on the label. However, a substitute product is most likely to originate from the U.S. compared to any other single country. Products that are produced by aquaculture and those that are wild caught are both playing a in role in seafood mislabeling.

Published in the Proceedings of the National Academy of Sciences, the study's most concerning finding is that seafood mislabeling is having negative consequences on the marine environment. Approximately 60% of U.S. mislabeled seafood involves only products that are wild caught. For those products, the substituted products come from fisheries with less healthy stocks and greater impacts on bycatch species compared to the product on the label. Similarly, substituted products are from fisheries with less effective management and with management policies less likely to address impacts of fishing on habitats and ecosystems.

At a systems-level, it appears that the conditions are in place for mislabeling to be generating negative impacts on marine populations and to support consumption of products from poorly managed fisheries--which is an important finding that supports programs and policies that target seafood mislabeling, says Kailin Kroetz, lead author and Assistant Professor at Arizona State University and University Fellow at Resources for the Future.

The authors also caution that more research is needed, and their findings should be viewed through a lens of uncertainty. This is partially because fisheries, trade, and mislabeling data are often scarce and challenging to work with because of the ways they are recorded and reported. Nonetheless, the research provides the first systematic evidence of environmental impacts from food fraud and highlights the need for more holistic, and collaborative approaches to understand and design interventions to minimize seafood mislabeling.

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More Information

For more information on seafood mislabeling, visit https://seafoodmislabeling.org

Contacts

Josh Donlan PhD, Advanced Conservation Strategies, jdonlan@advancedconservation.org

Kailin Kroetz PhD, Arizona State University, kailin.kroetz@asu.edu

Fish carcasses deliver toxic mercury pollution to the deepest ocean trenches

UNIVERSITY OF MICHIGAN

Research News

Photos // Animation

The sinking carcasses of fish from near-surface waters deliver toxic mercury pollution to the most remote and inaccessible parts of the world's oceans, including the deepest spot of them all: the 36,000-foot-deep Mariana Trench in the northwest Pacific.

And most of that mercury began its long journey to the deep-sea trenches as atmospheric emissions from coal-fired power plants, mining operations, cement factories, incinerators and other human activities.

Those are two of the main conclusions of a University of Michigan-led research team that analyzed the isotopic composition of mercury in fish and crustaceans collected at the bottom of two deep-sea trenches in the Pacific. The team reports its findings in a study scheduled for publication Nov. 16 in Proceedings of the National Academy of Sciences.

"Mercury that we believe had once been in the stratosphere is now in the deepest trench on Earth," said U-M environmental geochemist Joel Blum, lead author of the PNAS paper and a professor in the U-M Department of Earth and Environmental Sciences.

"It was widely thought that anthropogenic mercury was mainly restricted to the upper 1,000 meters of the oceans, but we found that while some of the mercury in these deep-sea trenches has a natural origin, it is likely that most of it comes from human activity."

At a scientific meeting in June, Blum's team and a Chinese-led research group independently reported the detection of human-derived mercury in deep-sea-trench organisms.

The Chinese researchers, who published their findings July 7 in the journal Nature Communications, concluded that the mercury gets to the deep-sea trenches by hitching a ride on microscopic particles of sinking organic matter--including fecal material and dead plankton--that constantly rain down from the upper oceans.

But in their PNAS paper, Blum and his colleagues suggest that a more likely explanation is that sinking carrion from fish that feed in the upper ocean delivers most of the mercury to the trenches.

Why does it matter whether deep-sea-trench mercury came from sinking fish carcasses or from the steady rain of tiny bits of detritus?

Because scientists and policymakers want to know how changing global mercury emissions will affect the levels found in seafood. While mercury emissions have declined in recent years in North America and Europe, China and India continue to expand their use of coal, and global-scale mercury emissions are rising.

To determine how seafood is likely to be impacted, researchers rely on global models. And refining those models requires the clearest possible understanding of how mercury cycles within the oceans and between the oceans and the atmosphere, according to Blum.

"Yes, we eat fish caught in shallower waters, not from deep-sea trenches," he said. "However, we need to understand the cycling of mercury through the entire ocean to be able to model future changes in the near-surface ocean."

Mercury is a naturally occurring element, but more than 2,000 metric tons of it are emitted into the atmosphere each year from human activities. This inorganic mercury can travel thousands of miles before being deposited onto land and ocean surfaces, where microorganisms convert some of it to methylmercury, a highly toxic organic form that can accumulate in fish to levels that are harmful to humans and wildlife.

Effects on humans can include damage to the central nervous system, the heart and the immune system. The developing brains of fetuses and young children are especially vulnerable.

In their study, Blum and his colleagues analyzed the isotopic composition of methylmercury from the tissues of snailfish and crustaceans called amphipods collected at depths of up to 33,630 feet in the Mariana Trench in the northwest Pacific, southwest of Guam. Other samples were collected at depths of up to 32,800 feet in the Kermadec Trench in the southwest Pacific, northeast of New Zealand.

"These samples were challenging to acquire, given the trenches' great depths and high pressures," said study co-author Jeffrey Drazen, a University of Hawaii oceanographer. "The trenches are some of the least studied ecosystems on Earth, and the Mariana snailfish was only just discovered in 2014."

Mercury has seven stable (nonradioactive) isotopes, and the ratio of the different isotopes provides a unique chemical signature, or fingerprint, that can be used as a diagnostic tool to compare environmental samples from various locations.

The researchers used these fingerprinting techniques--many of which were developed in Blum's lab--to determine that the mercury from deep-sea-trench amphipods and snailfish had a chemical signature that matched the mercury from a wide range of fish species in the central Pacific that feed at depths of around 500 meters (1,640 feet). Those central Pacific fish were analyzed by Blum and his colleagues during a previous study.

At the same time, they found that the isotopic composition of the mercury in sinking particles of detritus, the delivery mechanism favored by the Chinese team, does not match the chemical signature of mercury in the trench organisms, according to Blum and his colleagues.

They concluded that most of the mercury in the trench organisms was transported there in the carcasses of fish that feed in sunlit near-surface waters, where most of the mercury comes from anthropogenic sources.

"We studied the trench biota because they live in the deepest and most remote place on Earth, and we expected the mercury there to be almost exclusively of geologic origin--that is, from deep-sea volcanic sources," Blum said. "Our most surprising finding was that we found mercury in organisms from deep-sea trenches that shows evidence for originating in the sunlit surface zone of the ocean."

Anthropogenic mercury enters the oceans via rainfall, dry deposition of windblown dust, and runoff from rivers and estuaries.

"Deep-sea trenches have been viewed as pristine ecosystems unsullied by human activities. But recent studies have found traces of anthropogenic lead, carbon-14 from nuclear weapons testing, and persistent organic pollutants such as PCBs in organisms living in even the deepest part of the ocean, which is known as the hadal zone," Drazen said.

The latest mercury findings provide yet another example of human activities impacting food webs in the most remote marine ecosystems on Earth.

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The other authors of the PNAS paper, in addition to Blum and Drazen, are Brian Popp of the University of Hawaii at Manoa, Marcus Johnson and Laura Motta of the U-M Department of Earth and Environmental Sciences, and Alan Jamieson of Newcastle University.

The title of the study is "Mercury isotopes identify near-surface marine mercury in deep sea trench biota." The work was supported by the Schmidt Ocean Institute, several grants from the National Science Foundation, and an NSF Graduate Fellowship.

Joel Blum


#SOCIOBIOLOGY

Songbird parents evict young for their own benefit

UNIVERSITY OF ILLINOIS COLLEGE OF AGRICULTURAL, CONSUMER AND ENVIRONMENTAL SCIENCES

Research News

EMBARGOED UNTIL NOVEMBER 16, 2020 AT 3 PM US EASTERN TIME

URBANA, Ill. - Parents, you might know the feeling. When kids get pushy and demanding, it's a tempting fantasy to shove them out of the house and let them survive on their own. Of course, we'd never put our babies in harm's way, but according to new research from the University of Illinois, many songbird parents give nestlings the boot well before they're ready.

The study, published in the Proceedings of the National Academy of Sciences, shows the behavior is common in songbirds, appearing in 12 of 18 species studied in various habitats throughout the United States. Across species, nestlings were about 14% less likely to survive when they left the nest too early. If chicks suffer when they leave the nest too early, why do parents kick them out?

"Individual chicks may be less likely to survive, but by manipulating them out of the nest early, parents benefit through a 14% increase in their likelihood of raising at least one offspring to independence," says Todd Jones, doctoral student in the Department of Natural Resources and Environmental Sciences (NRES) at Illinois and lead author on the article.

In other words, parents avoid leaving all their eggs in one basket.

"The parents are distributing the risk," says Mike Ward, associate professor in NRES and senior author on the study. "The longer chicks stay in the nest, the greater the chance the whole brood will be lost to predators like snakes or raccoons. But we see parents physically separating chicks in space outside the nest, and that way, the probability of them all dying is almost zero."

The study adds to scientists' understanding of parent-offspring conflict, a concept in evolution describing the tradeoffs inherent to parental care. Putting a lot of resources into kids favors their survival, but can leave parents depleted, at risk of predation or disease, and potentially less able to produce additional offspring. Too little care, and offspring may not survive to carry parents' genes into the next generation. And from an evolutionary perspective, successfully passing genes along is the number one goal.

"For all organisms with parental care, there will always come a point where they're in conflict. In this case, it was a little surprising parents were putting chicks out in a dangerous situation that's good for the parent, but not good for the offspring," Ward says. "But it makes sense from an evolutionary perspective, for the parents."

Jones says surviving offspring eventually benefit, too, because the behavior is baked into their DNA.

"While the offspring are suffering a cost in the immediate term, down the road when they're breeding and they do the same thing to their kids, it's also benefiting them. This behavior is being passed down from generation to generation," he says.

The discovery explains an overlooked period in songbird life histories, the juvenile transition. Most previous research focused on what happens in the nest or immediately after fledging. This is the first study comparing survival rates before and after fledging across species and locations, demonstrating an almost universal post-fledging survival decline in these songbirds. It also establishes a baseline for what to expect, survival-wise, against a backdrop of environmental change.

"This has been really understudied, so any information we get on their survival or life histories during this period is really important, especially given anthropogenic landscape changes, global climate change, or what have you. Having that baseline information will allow us to detect shifts or changes in the future," Jones says.

Ward adds, "Some of these species are declining pretty dramatically throughout the Midwest. They're probably right on the razor's edge. So if predation goes up for some reason, it could really have big implications for that cohort throughout the years."

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The article, "Parental benefits and offspring costs reflect parent-offspring conflict over the age of fledging among songbirds," is published in the Proceedings of the National Academy of Sciences. Authors include Todd M. Jones, Jeffrey D. Brawn, Ian J. Ausprey, Andrew C. Vitz, Amanda D. Rodewald, Douglas W. Raybuck, Than J. Boves, Cameron J. Fiss, Darin J. McNeile, Scott H. Stoleson, Jeffery L. Larkin, W. Andrew Cox, Amy C. Schwarzer, Noah P. Horsley, Evalynn M. Trumbo, and Michael P. Ward.

The Department of Natural Resources and Environmental Sciences is in the College of Agricultural, Consumer and Environmental Sciences at the University of Illinois.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

Healthy sleep habits help lower risk of heart failure

Circulation journal report

AMERICAN HEART ASSOCIATION

Research News

DALLAS, November 16, 2020 -- Adults with the healthiest sleep patterns had a 42% lower risk of heart failure regardless of other risk factors compared to adults with unhealthy sleep patterns, according to new research published today in the American Heart Association's flagship journal Circulation. Healthy sleep patterns are rising in the morning, sleeping 7-8 hours a day and having no frequent insomnia, snoring or excessive daytime sleepiness.

Heart failure affects more than 26 million people, and emerging evidence indicates sleep problems may play a role in the development of heart failure.

This observational study examined the relationship between healthy sleep patterns and heart failure and included data on 408,802 UK Biobank participants, ages 37 to 73 at the time of recruitment (2006-2010). Incidence of heart failure was collected until April 1, 2019. Researchers recorded 5,221 cases of heart failure during a median follow-up of 10 years.

Researchers analyzed sleep quality as well as overall sleep patterns. The measures of sleep quality included sleep duration, insomnia and snoring and other sleep-related features, such as whether the participant was an early bird or night owl and if they had any daytime sleepiness (likely to unintentionally doze off or fall asleep during the daytime).

"The healthy sleep score we created was based on the scoring of these five sleep behaviors," said Lu Qi, M.D., Ph.D., corresponding author and professor of epidemiology and director of the Obesity Research Center at Tulane University in New Orleans. "Our findings highlight the importance of improving overall sleep patterns to help prevent heart failure."

Sleep behaviors were collected through touchscreen questionnaires. Sleep duration was defined into three groups: short, or less than 7 hours a day; recommended, or 7 to 8 hours a day; and prolonged, or 9 hours or more a day.

After adjusting for diabetes, hypertension, medication use, genetic variations and other covariates, participants with the healthiest sleep pattern had a 42% reduction in the risk of heart failure compared to people with an unhealthy sleep pattern.

They also found the risk of heart failure was independently associated and:

  • 8% lower in early risers;
  • 12% lower in those who slept 7 to 8 hours daily;
  • 17% lower in those who did not have frequent insomnia; and
  • 34% lower in those reporting no daytime sleepiness.

Participant sleep behaviors were self-reported, and the information on changes in sleep behaviors during follow-up were not available. The researchers noted other unmeasured or unknown adjustments may have also influenced the findings.

Qi also noted that the study's strengths include its novelty, prospective study design and large sample size.

First-author is Xiang Li, Ph.D.; other co-authors are Qiaochu Xue, M.P.H.; Mengying Wang, M.P.H.; Tao Zhou, Ph.D.; Hao Ma, Ph.D.; and Yoriko Heianza, Ph.D. Author disclosures are detailed in the manuscript.

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Funding sources include grants from the National Heart, Lung, and Blood Institute and the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health, the Boston Obesity Nutrition Research Center and the United States-Israel Binational Science Foundation. Also, Lu Qi, M.D., Ph.D., is the recipient of an American Heart Association Scientist Development Award, and Xiang Li, Ph.D., is the recipient of an American Heart Association Predoctoral Fellowship Award.

Additional Resources:

Statements and conclusions of studies published in the American Heart Association's scientific journals are solely those of the study authors and do not necessarily reflect the Association's policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. The Association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific Association programs and events. The Association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and biotech companies, device manufacturers and health insurance providers are available here, and the Association's overall financial information is available here.

About the American Heart Association

The American Heart Association is a relentless force for a world of longer, healthier lives. We are dedicated to ensuring equitable health in all communities. Through collaboration with numerous organizations, and powered by millions of volunteers, we fund innovative research, advocate for the public's health and share lifesaving resources. The Dallas-based organization has been a leading source of health information for nearly a century. Connect with us on heart.org , Facebook , Twitter or by calling 1-800-AHA-USA1.

CANADA

New ALS guideline establishes national standard for managing neurodegenerative disease

Best practice recommendations the first in Canada

CANADIAN MEDICAL ASSOCIATION JOURNAL

Research News

The first Canadian guideline for the care and management of patients with amyotrophic lateral sclerosis (ALS) -- Lou Gehrig's disease -- recommends a patient-focused approach, with attention to holistic and emotional aspects of well-being.

The guideline, published in CMAJ (Canadian Medical Association Journal), is intended for ALS clinicians, allied health professionals and primary care providers, and contains an easy-to-reference table with comprehensive recommendations. As new evidence may change management, the guideline will be updated every 5 years.

"These best practice recommendations are an important step forward in improving the lives of people living with ALS across the country and supporting their caregivers by addressing important issues," says Dr. Christen Shoesmith, neurologist and Motor Neuron Diseases Clinic director at London Health Sciences Centre in London, Ontario, and chair of the ALS guideline working group. "The emphasis on expert consensus relative to evidence-based recommendations highlights the need for more research in ALS management and underscores the challenges ALS clinicians face in managing patients with this complex and devastating disease."

About 3000 Canadians live with ALS, a debilitating degenerative disease affecting the brain and spinal cord that ultimately results in paralysis. ALS has no cure, and four out of five people with ALS will die within five years of being diagnosed.

The guideline is based on the best available evidence as well as expert consensus when evidence is lacking. It is intended to guide Canadian clinicians through issues unique to Canada and to update previous guidelines published in the United States and Europe.

  • Communications -- tailor the initial discussion about diagnosis to the patient's needs; information about ALS prognosis does not need to be provided at the time of diagnosis

  • Disease-modifying therapies -- have an open discussion with patients about the potential risks and benefits of both approved and unapproved therapies

  • Multidisciplinary care -- refer patients to specialized ALS multidisciplinary clinics for optimized health care delivery

  • Caregivers -- be attentive to the needs of caregivers and involve them in care planning

The guideline provides detailed recommendations for managing symptoms including pain, cramps, sleep disturbances, depression and anxiety as well as recommendations for respiratory management, nutrition, exercise, medication alignment, palliative care and more.

The authors emphasize the need for more research into ALS treatment and the challenges in caring for people with this disease.

Funding for the guideline was provided by the ALS Society of Canada and the Canadian ALS Research Network (CALS).

Listen to a podcast https://soundcloud.com/cmajpodcasts/191721-guide

"This guideline will enable ALS clinics across Canada to meet a common national standard, and to adapt as this standard continues to evolve over time. In doing so, ALS clinicians can offer the best possible care to their patients and help them to navigate this exceedingly complex and devastating disease," conclude the authors.

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"Canadian best practice recommendations for the management of amyotrophic lateral sclerosis" is published November 16, 2020.

Virginia Tech lab proves the concept of a natural approach to antiperspirants

VIRGINIA TECH

Research News

IMAGE

IMAGE: THE NATURE-INSPIRED FLUIDS AND INTERFACES LAB CREATED A SIMULATED SWEAT GLAND EXPERIMENT TO TEST THE THEORY OF NATURAL CLOGGING OF PORES. view more 

CREDIT: VIRGINIA TECH

Sweating is a natural function of the human body, allowing a body to cool itself as sweat emerges from glands and evaporates. Separately, this process may produce odors as bacteria present on the skin break down sweat proteins. A deodorant kills the bacteria that produce the odor, while an antiperspirant clogs sweat ducts to prevent sweat from emerging in the first place.

This clogging is commonly achieved by the use of metallic salts. There remains debate as to whether or not these metallic salts contribute to heath risks such as cancer, but demand by consumers for more natural alternatives to antiperspirants containing these metals (a sort of "just-in-case" scenario) is rapidly growing.

The Virginia Tech Nature-Inspired Fluids and Interfaces Lab, led by Associate Profesor Jonathan Boreyko, has just made a major breakthrough in the study of natural antiperspirants. Their theory is this: If the sweat can begin to evaporate while still inside of the sweat duct, before it emerges onto the skin, the sweat's own minerals will crystallize to clog the duct. In other words, the mixture of sodium, choride, potassium, calcium, urea, and bicarbonates naturally present in sweat can do the same work as the metallic salts used in commercial antiperspirants.

Testing the theory

To explore this idea, the group constructed an artificial "sweat rig" to investigate the possibilities. They used a microchannel made from pulled glass to serve as an artificial sweat duct, and created the function of a sweat gland by using pressurized gas to push synthetic sweat across tubing and into the connected glass duct.

To prove the concept, three different scenarios were tested. The first was a control, where no product was placed near the artificial sweat duct. For the second test, researchers placed a dry cube of the organic, silicon-based polymer PDMS near the exit of the duct. Finally, for the third test, the PDMS cube was infused with propylene glycol, a chemical that is highly attractive to water. These three scenarios allowed for a direct comparison of how sweat flowed when the duct was completely open, versus near a regular object, versus near an evaporation-inducing object.

The team observed the flow of the synthetic sweat, which has the same minerals as natural sweat, by focusing a microscope on the artificial duct. For the first two scenarios, the sweat flowed freely from the outlet of the sweat duct, which would correspond to sweat emerging onto the skin. But for the third scenario, where the duct was placed close to the evaporation-inducing material, the duct became clogged within seconds. A gel-like plug formed within the duct near the exit, creating a seal. Even when the pressure pushing the liquid was increased, the clog was able to maintain the seal.

"Over the past few years in particular, I've noticed that my wife and many of her friends have been transitioning to more natural cosmetic and cleaning products," said Boreyko. "There is also an increasing push from regulatory agencies, particularly in Europe, to restrict the use of metals in antiperspirants. Our research has discovered the most natural antiperspirant in existence: the minerals within the sweat itself! It is exciting to find that simply making the sweat evaporate faster can cause natural mineral plugs that have the potential of replacing metal-based products in the future."

With the concept proven, the team is moving toward application. Possibilities for extending the concept to human trials could include using an applicator stick, similar in form to current products, or a wearable adhesive. In either case, the next goal is to demonstrate in a human trial that the proper water-attracting product could facilitate natural clogging from the body's own sweat.

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Findings from this research were published in the journal ACS Applied Materials & Interfaces on Nov. 16, 2020.

When temperatures rise, dog ticks more likely to choose humans over canines

New study presented at TropMed20 shows how climate change could expand and intensify the risk of disease that kills one in five if not treated early


AMERICAN SOCIETY OF TROPICAL MEDICINE & HYGIENE

VIDEO: FOR THEIR EXPERIMENT, THEY CONSTRUCTED TWO LARGE WOODEN BOXES MEASURING ABOUT 3 FEET TALL AND 2 FEET WIDE, WHICH WERE THEN CONNECTED TO EACH OTHER BY A CLEAR PLASTIC TUBE.... view more

CREDIT: DON PREISLER-UC DAVIS SCHOOL OF VETERINARY MEDICINE

Arlington, Va. (November 16, 2020) -- A variety of ticks that carry the bacteria causing the deadly disease Rocky Mountain spotted fever (RMSF) are more than twice as likely to shift their feeding preference from dogs to humans when temperatures rise, a sign that climate change could expand and intensify human disease risks, according to a new study presented today at the Annual Meeting of the American Society of Tropical Medicine and Hygiene (ASTMH).

"Our work indicates that when the weather gets hot, we should be much more vigilant for infections of RMSF in humans," said Laura Backus, MPH, DVM, who led the study at the University of California, Davis School of Veterinary Medicine (UC-Davis). "We found that when temperatures rose from about 74 to 100 degrees Fahrenheit, brown dog ticks that carry the disease were 2.5 times more likely to prefer humans over dogs."

Cases of RMSF and related diseases, collectively known as spotted fever rickettsiosis, have risen dramatically over the last 20 years. The disease is treatable with antibiotics if detected in the first week of infection, but once an infection takes hold, the fatality rate for RMSF victims can exceed 20%. Complications can include damaged blood vessels; inflammation of the heart, lungs or brain; and kidney failure. Over the last 10 years, public health authorities have been particularly alarmed by a rash of deadly RMSF outbreaks among indigenous communities in Arizona and northern Mexico.

Backus said there have been indications from earlier work that brown dog ticks, which are found throughout the continental United States, may be more aggressive toward humans in hot weather. And scientists warn that climate change is greatly expanding areas of the country experiencing multiple days when temperatures top 100 degrees Fahrenheit, or about 38 degrees Celsius. Backus and her colleagues at UC-Davis wanted to gain more definitive insights into how rising temperatures might elevate the risk of RMSF infections.

For their experiment, they constructed two large wooden boxes measuring about 3 feet tall and 2 feet wide, which were then connected to each other by a clear plastic tube. They conducted a series of tests that involved putting a human in one box, a dog in the other and ticks in the clear plastic tube between them. The researchers then observed, over 20-minute intervals, whether the ticks, which seek out hosts to feed on based on smell, preferred dogs or humans--first at temperatures of around 74 degrees Fahrenheit (23.3 degrees Celsius) and then at 100 degrees Fahrenheit (37.8 degrees Celsius).

Backus said that at the higher temperature, one type of brown dog tick, known as the tropical lineage tick, was especially decisive in shifting its preferences from dogs to humans. Currently, tropical lineage brown dog ticks are found across the southern regions of the United States, in places like Arizona, Florida, southern California and southern Georgia. However, Backus said that their range is expected to move northward as climate change causes average temperatures to rise.

Brown dog ticks belonging to another lineage, the temperate lineage, are found throughout the lower 48 states and may also carry RMSF. Backus said that while the temperate ticks showed only a slight increase in preference for humans over dogs in the higher temperature test, they exhibited a pronounced decrease in their preference for dogs. Many ticks simply shifted from clearly pro-dog to neutral--they did not move toward either subject.

"We believe that this decreased preference for dogs--combined with a slight increase in preference for humans--suggests that hot temperatures may also elevate risks of RMSF in areas where the temperate ticks are more common," Backus said.

She added that it's important to identify conditions that can increase infection risks--and put health officials on higher alert--because symptoms in the crucial early phase of RMSF, when it's relatively easy to treat, can be mistaken for a number of more common ailments. They include headache, fever and muscle aches. Backus said there is also a need for better diagnostic tests since the existing test is time-consuming and may produce false negatives.

"The findings from the use of this simple but effective laboratory experiment to gauge how rising temperatures might lead to more human infections with a very dangerous tick-borne pathogen adds to the growing evidence of the increasing connection between climate change and its impact on health," said ASTMH President Joel Breman, MD, DTPH, FASTM. "Climate change is moving so quickly that it is critical to keep pace with the many ways it may alter and intensify the risk of a wide range of infectious diseases so we are better prepared to diagnose, treat and prevent them."

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About the American Society of Tropical Medicine and Hygiene

The American Society of Tropical Medicine and Hygiene, founded in 1903, is the largest international scientific organization of experts dedicated to reducing the worldwide burden of tropical infectious diseases and improving global health. It accomplishes this through generating and sharing scientific evidence, informing health policies and practices, fostering career development, recognizing excellence, and advocating for investment in tropical medicine/global health research. For more information, visit astmh.org.