Stress can turn hair gray

 

A new study offers quantitative evidence linking psychological stress to graying hair in people.

Though the legend is inaccurate -- hair that has already grown out of the follicle does not change color -- a new study from researchers at Columbia University Vagelos College of Physicians and Surgeons is the first to offer quantitative evidence linking psychological stress to graying hair in people.

And while it may seem intuitive that stress can accelerate graying, the researchers were surprised to discover that hair color can be restored when stress is eliminated, a finding that contrasts with a recent study in mice that suggested that stressed induced gray hairs are permanent.

The study, published June 22 in eLife, has broader significance than confirming age-old speculation about the effects of stress on hair color, says the study's senior author Martin Picard, PhD(link is external and opens in a new window), associate professor of behavioral medicine (in psychiatry and neurology) at Columbia University Vagelos College of Physicians and Surgeons.

"Understanding the mechanisms that allow 'old' gray hairs to return to their 'young' pigmented states could yield new clues about the malleability of human aging in general and how it is influenced by stress," Picard says.

"Our data add to a growing body of evidence demonstrating that human aging is not a linear, fixed biological process but may, at least in part, be halted or even temporarily reversed."

The investigators immediately noticed that some gray hairs naturally regain their original color, which had never been quantitatively documented, Picard says.

When hairs were aligned with stress diaries by Shannon Rausser, second author on the paper and a student in Picard's laboratory, striking associations between stress and hair graying were revealed and, in some cases, a reversal of graying with the lifting of stress.

"There was one individual who went on vacation, and five hairs on that person's head reverted back to dark during the vacation, synchronized in time," Picard says.

Blame the mind-mitochondria connection

To better understand how stress causes gray hair, the researchers also measured levels of thousands of proteins in the hairs and how protein levels changed over the length of each hair.

Changes in 300 proteins occurred when hair color changed, and the researchers developed a mathematical model that suggests stress-induced changes in mitochondria may explain how stress turns hair gray.

"We often hear that the mitochondria are the powerhouses of the cell, but that's not the only role they play," Picard says. "Mitochondria are actually like little antennas inside the cell that respond to a number of different signals, including psychological stress."

The mitochondria connection between stress and hair color differs from that discovered in a recent study of mice, which found that stress-induced graying was caused by an irreversible loss of stem cells in the hair follicle.

"Our data show that graying is reversible in people, which implicates a different mechanism," says co-author Ralf Paus, PhD, professor of dermatology at the University of Miami Miller School of Medicine. "Mice have very different hair follicle biology, and this may be an instance where findings in mice don't translate well to people."

Hair re-pigmentation only possible for some

Reducing stress in your life is a good goal, but it won't necessarily turn your hair to a normal color.

"Based on our mathematical modeling, we think hair needs to reach a threshold before it turns gray," Picard says. "In middle age, when the hair is near that threshold because of biological age and other factors, stress will push it over the threshold and it transitions to gray.

"But we don't think that reducing stress in a 70-year-old who's been gray for years will darken their hair or increasing stress in a 10-year-old will be enough to tip their hair over the gray threshold."

More information

The study is titled "Quantitative Mapping of Human Hair Greying and Reversal in Relation to Life Stress."

All contributors (all from Columbia unless noted): Ayelet Rosenberg, Shannon Rausser, Junting Ren, Eugene V. Mosharov, Gabriel Sturm, R. Todd Ogden, Purvi Patel, Rajesh Kumar Soni, Clay Lacefield (New York State Psychiatric Institute), Desmond J. Tobin (University College Dublin), Ralf Paus (University of Miami, University of Manchester, UK, and Monasterium Laboratory, Münster, Germany), and Martin Picard.

The research was funded by grants from the Wharton Fund and the National Institutes of Health (grants GM119793, MH119336, and AG066828).

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Revelation – Jesus Out Everywhere

 

Revelation – Jesus Out  Everywhere  – Revelation  is back with yet another masterpiece, which he entitles “Jesus Out Everywhere ”.

Download Here

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African great apes to suffer massive range loss in next 30 years

 A new study predicts massive range declines of Africa's great apes -- gorillas, chimpanzees and bonobos -- due to the impacts of climate change, land-use changes and human population growth.

For their analysis, the authors compiled information on African ape occurrence held in the IUCN SSC A.P.E.S. database, a repository that includes a remarkable amount of information on population status, threats and conservation for several hundred sites, collected over 20 years.

The first-of-its-kind study quantifies the joint effects of climate, land-use, and human population changes across African ape ranges for the year 2050 under best- and worst-case scenarios. "Best case" implies slowly declining carbon emissions and that appropriate mitigation measures will be put in place. "Worst case" assumes that emissions continue to increase unchecked -- business as usual.

Under the best-case scenario, the authors predict that great apes will lose 85 percent of their range, of which 50 percent will be outside national parks and other areas protected by legislation. Under the worst-case scenario, they predict a 94 percent loss, of which 61 percent will be in areas that are not protected.

This paper examines whether great apes can or cannot disperse away from where they are currently found, and the best- and worst-case scenarios in each case. For example, mountains are currently less suitable than lowland areas for some great ape species. However, climate change will render some lowlands less suitable -- warmer, drier, perhaps less food available -- but the nearby mountains will take on the characteristics that those lowlands currently have. If great apes are able to physically move from the lowlands to the mountains, they may be able to survive, and even increase their range (depending on the species, and whether it is the best- or worst-case scenario). However, they may not be able to travel (disperse) away from the lowlands in the time remaining between today and 2050.

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Train your brain with computer game to eat less sugar

A recent study shows that a computer game can be used to train its players to eat less sugar, as way of reducing their weight and improving their health.

More than half of American adults consume excess added sugars, according to the U.S. Department of Health and Human Services. Major dietary guidelines recommend limiting foods high in added sugars. A recent study led by Evan Forman, PhD, a psychology professor in Drexel University's College of Arts and Sciences, shows that a computer game can be used to train its players to eat less sugar, as way of reducing their weight and improving their health.

"Added sugar is one of the biggest culprits of excess calories and is also associated with several health risks including cancer," said Forman, who also leads the Center for Weight, Eating and Lifestyle Science (WELL Center) at Drexel. "For these reasons, eliminating added sugar from a person's diet results in weight loss and reduced risk of disease."

As part of their study, which was recently published in the Journal of Behavioral Medicine, the researchers developed and evaluated a "brain training" game targeting the part of the brain that inhibits impulses with the hope that it would improve diet, specifically by decreasing the consumption of sweet foods. Think: Lumosity for your diet.

"Cognitive, or 'brain, training' games have been used to help people reduce unhealthy habits, like smoking," said Forman. "We were also seeing positive results from labs using computer training programs."

This research is the first to examine the impact of this type of "highly personalized and/or gamified inhibitory control training" on weight loss using repeated, at-home trainings, according to Forman.

Forman's group conceptualized a game based on cognitive training and worked with Michael Wagner, a professor and head of the Digital Media department in Drexel's Westphal College of Media Arts & Design, and a group of digital media students to develop it into a computer-based game, called "Diet DASH," for purposes of the study.

The game automatically customized the training to focus on the sweets that each participant tended to eat and adjusted the difficulty according to how well they were resisting the temptation of sweets.

The trial randomized 109 participants who were overweight and ate sweets. Participants attended a workshop prior to starting the game to help them understand why sugar is detrimental to their health and to learn which foods to avoid and methods for doing so.

"The workshop helped give participants strategies for following a no-sugar diet. However, we hypothesized that participants would need an extra tool to help manage sweets cravings," said Forman. "The daily trainings could make or break a person's ability to follow the no-added sugar diet. They strengthen the part of your brain to not react to the impulse for sweets."

Participants then played the game on a computer for a few minutes every day for six weeks and then again once a week for two weeks.

In the game, players move as quickly as possible through a grocery store with the goal of putting the correct food (healthy foods) in a grocery cart, while refraining from choosing the incorrect foods (their preferred sweet). Points were awarded for correct items placed in carts.

For over half of the participants, who showed higher preferences toward sweets, playing the game helped them lose as much as 3.1 percent of their body weight over eight weeks. Participants also indicated that they found the daily training satisfactory, that it became part of their daily routine and that they wished to continue the trainings if they were available.

"The study's findings offer qualified support for the use of a computerized cognitive training to facilitate weight loss," said Forman.

The study also randomized whether participants received a highly gamified (enhanced graphics and sounds) or a less-gamified versions of the training. While the difference between the level of gamification did not matter, overall, to whether participants reduced sugar consumption and lost weight, they did find that the few men in the study reacted better to the highly gamified version than the women in the study. The WELL Center is now conducting a new trial with the highly gamified version of this training specifically for men and is actively recruiting participants.

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Climate change is giving old trees a growth spurt

Larch trees in the permafrost forests of northeastern China -- the northernmost tree species on Earth -- are growing faster as a result of climate change. A new study of growth rings from Dahurian larch in China's northern forests finds the hardy trees grew more from 2005 to 2014 than in the preceding 40 years.

A new study of growth rings from Dahurian larch in China's northern forests finds the hardy trees grew more from 2005 to 2014 than in the preceding 40 years. The findings also show the oldest trees have had the biggest growth spurts: Trees older than 400 years grew more rapidly in those 10 years than in the past 300 years, according to the new study.

The study's authors suspect warmer soil temperatures are fueling the growth spurts by lowering the depth of the permafrost layer, allowing the trees' roots to expand and suck up more nutrients.

The increased growth is good for the trees in the short-term but may be disastrous for the forests in the long-term, according to the authors. As the climate continues to warm, the permafrost underneath the trees may eventually degrade and no longer be able to support the slow-growing trees.

No other tree species can survive the permafrost plains this far north, so if the larch forests of northern Asia disappear, the entire ecosystem would change, according to the study's authors.

"The disappearance of larch would be a disaster to the forest ecosystem in this region," said Xianliang Zhang, an ecologist at Shenyang Agricultural University in Shenhang, China, and lead author of the new study in AGU's Journal of Geophysical Research: Biogeosciences.

Earth's hardiest trees

Dahurian larch is Earth's northernmost tree species and its most cold-hardy: These larches are the only trees that can tolerate the frigid permafrost plains of Russia, Mongolia and northern China. Chinese locals refer to Dahurian larch as "thin-old-trees," because they grow slowly in the thin active layer of soil above the permafrost and can live for more than 400 years.

Permafrost regions around the world have been thawing in recent decades due to rising temperatures, sometimes degrading into swamps and wetlands. In the new study, Zhang and his colleagues analyzed growth rings from more than 400 Dahurian larch in old-growth forests of northeastern China, the southernmost portion of the tree's range, to see how the trees are faring in a warming climate.

Tree rings allow scientists to measure how much trees grow from year to year. Much like people, trees do most of their growing while young. Dahurian larch generally grow rapidly until they become around 150 years old, at which point their growth slows. When the trees hit 300 years old, their growth basically stalls.

The researchers used the width of each tree's growth rings to calculate how much area each tree gained in cross-section each year over the course of its lifetime.

The results show Dahurian larch trees grew more from 2005 to 2014 than from 1964 to 2004. Interestingly, the effect was most pronounced in the oldest trees: Trees older than 300 years grew 80 percent more from 2005 to 2014 than in the preceding 40 years. Trees between 250 and 300 years old grew 35 percent more during that time period, while trees younger than 250 years grew between 11 and 13 percent more.

The old trees' growth is unusual -- it's akin to a 100-year-old person suddenly getting taller, according to Zhang. The authors suspect older trees are growing more than younger trees because they have more developed root systems that can harvest resources from the soil more efficiently.

The researchers compared the trees' growth rates to climate factors like soil temperatures and precipitation data over the past 50 years to see what was causing the unusual growth. They found increased soil temperatures, especially in winter, are likely powering the growth spurts. They suspect the warmer temperatures lower the depth of the permafrost layer, providing the trees' roots more room to expand and access to more nutrients.

While this initial soil warming has benefitted Dahurian larch, further permafrost thaw could likely decrease tree growth and even cause the forest to decay, according to the authors. Dahurian larch can't survive in wet conditions, so permafrost changing to wetlands or peatlands would be detrimental to the forest as a whole, they said.

"If the larch forest retreat in this region in the future, it is also not a good sign for the whole boreal forest," Zhang said.

While other research has examined the effects of a warming climate on temperature-sensitive trees in North America, the new study examined temperature-sensitive trees in permafrost areas, which have been less widely studied but are a vast component of the boreal forest, said Erika Wise, an associate professor of geography at the University of North Carolina -- Chapel Hill, who was not involved in the new study. Additionally, previous studies on these larch trees have focused on the effects of air temperature and precipitation, but the new study looked at the influence of ground surface temperatures, which has also not been studied widely, she added.

"Their arguments make a lot of logical sense in terms of why the trees might benefit from the increased winter ground surface temperatures, which is that especially things like an earlier spring thaw could really help trees get growing earlier, more ability to have root activity in the cold months, these sort of things would make sense in why trees would benefit from warmer winters in particular," Wise said. new study of growth rings from Dahurian larch in China's northern forests finds the hardy trees grew more from 2005 to 2014 than in the preceding 40 years. The findings also show the oldest trees have had the biggest growth spurts: Trees older than 400 years grew more rapidly in those 10 years than in the past 300 years, according to the new study.

The study's authors suspect warmer soil temperatures are fueling the growth spurts by lowering the depth of the permafrost layer, allowing the trees' roots to expand and suck up more nutrients.

The increased growth is good for the trees in the short-term but may be disastrous for the forests in the long-term, according to the authors. As the climate continues to warm, the permafrost underneath the trees may eventually degrade and no longer be able to support the slow-growing trees.

No other tree species can survive the permafrost plains this far north, so if the larch forests of northern Asia disappear, the entire ecosystem would change, according to the study's authors.

"The disappearance of larch would be a disaster to the forest ecosystem in this region," said Xianliang Zhang, an ecologist at Shenyang Agricultural University in Shenhang, China, and lead author of the new study in AGU's Journal of Geophysical Research: Biogeosciences.

Earth's hardiest trees

Dahurian larch is Earth's northernmost tree species and its most cold-hardy: These larches are the only trees that can tolerate the frigid permafrost plains of Russia, Mongolia and northern China. Chinese locals refer to Dahurian larch as "thin-old-trees," because they grow slowly in the thin active layer of soil above the permafrost and can live for more than 400 years.

Permafrost regions around the world have been thawing in recent decades due to rising temperatures, sometimes degrading into swamps and wetlands. In the new study, Zhang and his colleagues analyzed growth rings from more than 400 Dahurian larch in old-growth forests of northeastern China, the southernmost portion of the tree's range, to see how the trees are faring in a warming climate.

Tree rings allow scientists to measure how much trees grow from year to year. Much like people, trees do most of their growing while young. Dahurian larch generally grow rapidly until they become around 150 years old, at which point their growth slows. When the trees hit 300 years old, their growth basically stalls.

The researchers used the width of each tree's growth rings to calculate how much area each tree gained in cross-section each year over the course of its lifetime.

The results show Dahurian larch trees grew more from 2005 to 2014 than from 1964 to 2004. Interestingly, the effect was most pronounced in the oldest trees: Trees older than 300 years grew 80 percent more from 2005 to 2014 than in the preceding 40 years. Trees between 250 and 300 years old grew 35 percent more during that time period, while trees younger than 250 years grew between 11 and 13 percent more.

The old trees' growth is unusual -- it's akin to a 100-year-old person suddenly getting taller, according to Zhang. The authors suspect older trees are growing more than younger trees because they have more developed root systems that can harvest resources from the soil more efficiently.

The researchers compared the trees' growth rates to climate factors like soil temperatures and precipitation data over the past 50 years to see what was causing the unusual growth. They found increased soil temperatures, especially in winter, are likely powering the growth spurts. They suspect the warmer temperatures lower the depth of the permafrost layer, providing the trees' roots more room to expand and access to more nutrients.

While this initial soil warming has benefitted Dahurian larch, further permafrost thaw could likely decrease tree growth and even cause the forest to decay, according to the authors. Dahurian larch can't survive in wet conditions, so permafrost changing to wetlands or peatlands would be detrimental to the forest as a whole, they said.

"If the larch forest retreat in this region in the future, it is also not a good sign for the whole boreal forest," Zhang said.

While other research has examined the effects of a warming climate on temperature-sensitive trees in North America, the new study examined temperature-sensitive trees in permafrost areas, which have been less widely studied but are a vast component of the boreal forest, said Erika Wise, an associate professor of geography at the University of North Carolina -- Chapel Hill, who was not involved in the new study. Additionally, previous studies on these larch trees have focused on the effects of air temperature and precipitation, but the new study looked at the influence of ground surface temperatures, which has also not been studied widely, she added.

"Their arguments make a lot of logical sense in terms of why the trees might benefit from the increased winter ground surface temperatures, which is that especially things like an earlier spring thaw could really help trees get growing earlier, more ability to have root activity in the cold months, these sort of things would make sense in why trees would benefit from warmer winters in particular," Wise said.

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The oceans contain nearly 200,000 kinds of viruses

Nearly 200,000 different kinds of viruses swirl in the world’s oceans, according to a new study, Quanta Magazine reports. 

The new count is 12 times higher than what the previous census of marine viruses recorded in 2016. The reasons for the jump, researchers says, include extensive expeditions to collect samples and improved tools for genetic analysis. Roughly 90% of the viruses identified were new to science, they report today in Cell. This new appreciation of the viral diversity of the seas could help clarify the role of such microbes in the ocean’s carbon cycle, where they can kill or manipulate bacteria that might otherwise capture or release carbon dioxide from the atmosphere.

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DRC expands Ebola vaccine campaign as cases mount rapidly

The Democratic Republic of the Congo (DRC) will expand its use of the experimental Ebola vaccine that more than 110,000 have already received to try to stop an unusually stubborn outbreak of the disease. New vaccination strategies will attempt to reduce the security risks faced by health care workers in the outbreak region, which is home to nearly two dozen rebel groups—some of which have attacked response teams.

There’s also a bit of good news in this bleak situation: A new analysis of the vaccine dose needed to protect people found that the amount can be substantially reduced—by more than half for some people—essentially eliminating a long-standing concern about a potential vaccine shortage.

The changes follow recommendations made today by a group of vaccine experts that advises the World Health Organization (WHO) in Geneva, Switzerland. The 9-month-old outbreak in the northeastern region of the DRC as of 6 May had sickened 1506 people, 1045 of whom have died. (Only the Ebola outbreak that exploded in West Africa in 2014 had more cases and deaths.) The outbreak has spiked over the past month, with more than 400 new cases in April alone—a doubling from March—which WHO says reflects the recent disruption of the response because of violence.

A preliminary report issued last month by WHO showed the vaccine has been extremely effective in people who received it, and it has become a cornerstone in the effort to contain the outbreak. But so far, response teams have only offered the vaccine to people who came in direct contact with a known case or were a contact of a contact. Vaccinating only these two “rings” of people around cases—as opposed to, say, entire towns or regions—theoretically can stop spread with a limited vaccine campaign. But it hasn’t so far in the DRC. In its report released today, WHO’s Strategic Advisory Group of Experts (SAGE) on Immunization expresses its “grave concern” about the worsening epidemiology and recommends adding a third protective ring: everyone in a community—defined as a village or a neighborhood in a city—where a case occurs, regardless of contact history.

WHO’s Ana Maria Restrepo, who leads the vaccine effort in conjunction with the DRC’s Ministry of Health, says she hopes doing so will also reduce tensions about the shot, which some communities have resisted in part because of confusion about why some were eligible and others were not. Rather than going house to house, Restrepo says, vaccination teams will now work at special sites, protected by security teams, like the health center in an affected village or city neighborhood. This will also simplify the informed consent process by allowing health care workers to educate groups of people, instead of individuals, about the jabs’ risks and benefits. “So instead of using, for example, 15, 20 minutes per person, now you use 15, 20 minutes for 15 people,” she says.

Merck of Kenilworth, New Jersey, makes the vaccine, which contains a harmless vesicular stomatitis virus (VSV) engineered to carry a gene for an Ebola virus surface protein. One month ago, Merck said it had shipped 145,000 doses of the vaccine to WHO and had another 195,000 doses in its stockpile. In addition to the DRC, health care workers in neighboring Uganda and South Sudan have been receiving the vaccine in case the virus jumps borders. Merck has applied for regulatory approval of the vaccine, which first proved its worth in a clinical trial staged in Guinea 3 years ago, near the end of West African epidemic.

To Restrepo’s surprise, a recent analysis revealed that WHO, in effect, has “much more vaccine” than it had calculated, she says. As part of the approval process, Merck submitted the vaccine to the U.S. Food and Drug Administration (FDA), which the company optimized to improve its shelf life. FDA found the vials had twice the dose that was given in Guinea, which means the existing stockpile will go twice as far.

With SAGE’s approval, WHO now plans to use an even lower dose for the third ring, extending the vaccine even further. The VSV in the vaccine copies itself, and the Guinean study found that with a dose of 0.5 milliliters, it takes 10 days to properly immunize someone. But studies have shown that a 0.2-milliliter dose will trigger the same level of protective antibodies in 28 days, which WHO thinks is sufficient for people in that third ring.

All told, says Restrepo, these new strategies mean WHO has about 1 million doses of the vaccine available. “I had a glass of wine last week to celebrate that,” she says.

A broader vaccine program for people at lower risk still may soon launch, too, with a different experimental product. The SAGE recommendations call for offering an Ebola vaccine made by Johnson & Johnson of New Brunswick, New Jersey, to everyone in a DRC “health zone” that has a case of the disease, or even those in neighboring health zones. This will potentially protect even more people without affecting the stockpile of Merck vaccine, and also offers a real-world chance to test the Johnson & Johnson vaccine. The vaccine requires two shots of different formulations that researchers hope trigger a more durable immunity than the Merck vaccine, potentially helping to thwart future outbreaks in the region.

Michael Ryan, executive director of WHO’s Health Emergencies Programme, stresses that political and religious leaders in the area have to compel the insurgents in the area to stop attacking health care workers and the facilities where they treat people. On 19 April, Richard Valery Mouzoko Kiboung, a Cameroonian epidemiologist working for WHO, was shot and killed, and Doctors Without Borders in February had to evacuate staff from two of its Ebola treatment centers after they were attacked. The insurgents, Ryan says, “have to stop playing games with our lives and the lives of their own people.”

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