The search for youthfulness typically turns to lotions, supplements, serums and diets, but there may soon be a new option joining the fray. Rapamycin, a FDA-approved drug normally used to prevent organ rejection after transplant surgery, may also slow aging in human skin, according to a study from Drexel University College of Medicine researchers published in Geroscience.
Basic science studies have previously used the drug to slow aging in mice, flies, and worms, but the current study is the first to show an effect on aging in human tissue, specifically skin -- in which signs of aging were reduced. Changes include decreases in wrinkles, reduced sagging and more even skin tone -- when delivered topically to humans.
"As researchers continue to seek out the elusive 'fountain of youth' and ways to live longer, we're seeing growing potential for use of this drug," said senior author Christian Sell, PhD, an associate professor of Biochemistry and Molecular Biology at the College of Medicine. "So, we said, let's try skin. It's a complex organism with immune, nerve cells, stem cells -- you can learn a lot about the biology of a drug and the aging process by looking at skin."
In the current Drexel-led study, 13 participants over age 40 applied rapamycin cream every 1-2 days to one hand and a placebo to the other hand for eight months. The researchers checked on subjects after two, four, six and eight months, including conducting a blood test and a biopsy at the six- or eight-month mark.
After eight months, the majority of the rapamycin hands showed increases in collagen protein, and statistically significant lower levels of p16 protein, a key marker of skin cell aging. Skin that has lower levels of p16 has fewer senescent cells, which are associated with skin wrinkles. Beyond cosmetic effects, higher levels of p16 can lead to dermal atrophy, a common condition in seniors, which is associated with fragile skin that tears easily, slow healing after cuts and increased risk of infection or complications after an injury.
So how does rapamycin work? Rapamycin blocks the appropriately named "target of rapamycin" (TOR), a protein that acts as a mediator in metabolism, growth and aging of human cells. The capability for rapamycin to improve human health beyond outward appearance is further illuminated when looking deeper at p16 protein, which is a stress response that human cells undergo when damaged, but is also a way of preventing cancer. When cells have a mutation that would have otherwise created a tumor, this response helps prevent the tumor by slowing the cell cycle process. Instead of creating a tumor, it contributes to the aging process.
"When cells age, they become detrimental and create inflammation," said Sell. "That's part of aging. These cells that have undergone stress are now pumping out inflammatory markers."
In addition to its current use to prevent organ rejection, rapamycin is currently prescribed (in higher doses than used in the current study) for the rare lung disease lymphangioleiomyomatosis, and as an anti-cancer drug. The current Drexel study shows a second life for the drug in low doses, including new applications for studying rapamycin to increase human lifespan or improve human performance.
Rapamycin -- first discovered in the 1970s in bacteria found in the soil of Easter Island -- also reduces stress in the cell by attacking cancer-causing free radicals in the mitochondria.
In previous studies, the team used rapamycin in cell cultures, which reportedly improved cell function and slowed aging.
In 1996, a study in Cell of yeast cultures which used rapamycin to block TOR proteins in yeast, made the yeast cells smaller, but increased their lifespan.
"If you ramp the pathway down you get a smaller phenotype," said Sell. "When you slow growth, you seem to extend lifespan and help the body repair itself -- at least in mice. This is similar to what is seen in calorie restriction."
Read more at Science Daily
Nov 26, 2019
First recording of a blue whale's heart rate
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| Blue whale |
This device was fresh off a daylong ride on Earth's largest species -- a blue whale. Four suction cups had secured the sensor-packed tag near the whale's left flipper, where it recorded the animal's heart rate through electrodes embedded in the center of two of the suction feet. The details of this tag's journey and the heart rate it delivered were published Nov. 25 in Proceedings of the National Academy of Sciences.
"We had no idea that this would work and we were skeptical even when we saw the initial data. With a very keen eye, Paul Ponganis -- our collaborator from the Scripps Institution of Oceanography -- found the first heart beats in the data," said Jeremy Goldbogen, assistant professor of biology in the School of Humanities Sciences at Stanford and lead author of the paper. "There were a lot of high fives and victory laps around the lab."
Analysis of the data suggests that a blue whale's heart is already working at its limit, which may explain why blue whales have never evolved to be bigger. The data also suggest that some unusual features of the whale's heart might help it perform at these extremes. Studies like this add to our fundamental knowledge of biology and can also inform conservation efforts.
"Animals that are operating at physiological extremes can help us understand biological limits to size," said Goldbogen. "They may also be particularly susceptible to changes in their environment that could affect their food supply. Therefore, these studies may have important implications for the conservation and management of endangered species like blue whales."
Penguins to whales
A decade ago, Goldbogen and Ponganis measured the heart rates of diving emperor penguins in Antarctica's McMurdo Sound. For years after, they wondered whether a similar task could be accomplished with whales.
"I honestly thought it was a long shot because we had to get so many things right: finding a blue whale, getting the tag in just the right location on the whale, good contact with the whale's skin and, of course, making sure the tag is working and recording data," said Goldbogen.
The tag performed well on smaller, captive whales, but getting it near a wild blue whale's heart is a different task. For one thing, wild whales aren't trained to flip belly-up. For another, blue whales have accordion-like skin on their underside that expands during feeding, and one such gulp could pop the tag right off.
"We had to put these tags out without really knowing whether or not they were going to work," recalled David Cade, a recent graduate of the Goldbogen Lab who is a co-author of the paper and who placed the tag on the whale. "The only way to do it was to try it. So we did our best."
Cade stuck the tag on his first attempt and, over time, it slid into a position near the flipper where it could pick up the heart's signals. The data it captured showed striking extremes.
When the whale dove, its heart rate slowed, reaching an average minimum of about four to eight beats per minute -- with a low of two beats per minute. At the bottom of a foraging dive, where the whale lunged and consumed prey, the heart rate increased about 2.5 times the minimum, then slowly decreased again. Once the whale got its fill and began to surface, the heart rate increased. The highest heart rate -- 25 to 37 beats per minutes -- occurred at the surface, where the whale was breathing and restoring its oxygen levels.
An elastic heart
This data was intriguing because the whale's highest heart rate almost outpaced predictions while the lowest heart rate was about 30 to 50 percent lower than predicted. The researchers think that the surprisingly low heart rate may be explained by a stretchy aortic arch -- part of the heart that moves blood out to the body -- which, in the blue whale, slowly contracts to maintain some additional blood flow in between beats. Meanwhile, the impressively high rates may depend on subtleties in the heart's movement and shape that prevent the pressure waves of each beat from disrupting blood flow.
Looking at the big picture, the researchers think the whale's heart is performing near its limits. This may help explain why no animal has ever been larger than a blue whale -- because the energy needs of a larger body would outpace what the heart can sustain.
Now, the researchers are hard at work adding more capabilities to the tag, including an accelerometer, which could help them better understand how different activities affect heart rate. They also want to try their tag on other members of the rorqual whale group, such as fin whales, humpbacks and minke whales.
"A lot of what we do involves new technology and a lot of it relies on new ideas, new methods and new approaches," said Cade. "We're always looking to push the boundaries of how we can learn about these animals."
Read more at Science Daily
Scientists inch closer than ever to signal from cosmic dawn
Around 12 billion years ago, the universe emerged from a great cosmic dark age as the first stars and galaxies lit up. With a new analysis of data collected by the Murchison Widefield Array (MWA) radio telescope, scientists are now closer than ever to detecting the ultra-faint signature of this turning point in cosmic history.
In a paper on the preprint site ArXiv and soon to be published in the Astrophysical Journal, researchers present the first analysis of data from a new configuration of the MWA designed specifically to look for the signal of neutral hydrogen, the gas that dominated the universe during the cosmic dark age. The analysis sets a new limit -- the lowest limit yet -- for the strength of the neutral hydrogen signal.
"We can say with confidence that if the neutral hydrogen signal was any stronger than the limit we set in the paper, then the telescope would have detected it," said Jonathan Pober, an assistant professor of physics at Brown University and corresponding author on the new paper. "These findings can help us to further constrain the timing of when the cosmic dark ages ended and the first stars emerged."
The research was led by Wenyang Li, who performed the work as a Ph.D. student at Brown. Li and Pober collaborated with an international group of researchers working with the MWA.
Despite its importance in cosmic history, little is known about the period when the first stars formed, which is known as the Epoch of Reionization (EoR). The first atoms that formed after the Big Bang were positively charged hydrogen ions -- atoms whose electrons were stripped away by the energy of the infant universe. As the universe cooled and expanded, hydrogen atoms reunited with their electrons to form neutral hydrogen. And that's just about all there was in the universe until about 12 billion years ago, when atoms started clumping together to form stars and galaxies. Light from those objects re-ionized the neutral hydrogen, causing it to largely disappear from interstellar space.
The goal of projects like the one happening at MWA is to locate the signal of neutral hydrogen from the dark ages and measure how it changed as the EoR unfolded. Doing so could reveal new and critical information about the first stars -- the building blocks of the universe we see today. But catching any glimpse of that 12-billion-year-old signal is a difficult task that requires instruments with exquisite sensitivity.
When it began operating in 2013, the MWA was an array of 2,048 radio antennas arranged across the remote countryside of Western Australia. The antennas are bundled together into 128 "tiles," whose signals are combined by a supercomputer called the Correlator. In 2016, the number of tiles was doubled to 256, and their configuration across the landscape was altered to improve their sensitivity to the neutral hydrogen signal. This new paper is the first analysis of data from the expanded array.
Neutral hydrogen emits radiation at a wavelength of 21 centimeters. As the universe has expanded over the past 12 billion years, the signal from the EoR is now stretched to about 2 meters, and that's what MWA astronomers are looking for. The problem is there are myriad other sources that emit at the same wavelength -- human-made sources like digital television as well as natural sources from within the Milky Way and from millions of other galaxies.
"All of these other sources are many orders of magnitude stronger than the signal we're trying to detect," Pober said. "Even an FM radio signal that's reflected off an airplane that happens to be passing above the telescope is enough to contaminate the data."
To home in on the signal, the researchers use a myriad of processing techniques to weed out those contaminants. At the same time, they account for the unique frequency responses of the telescope itself.
"If we look at different radio frequencies or wavelengths, the telescope behaves a little differently," Pober said. "Correcting for the telescope response is absolutely critical for then doing the separation of astrophysical contaminants and the signal of interest."
Those data analysis techniques combined with the expanded capacity of the telescope itself resulted in a new upper bound of the EoR signal strength. It's the second consecutive best-limit-to-date analysis to be released by MWA and raises hope that the experiment will one day detect the elusive EoR signal.
Read more at Science Daily
In a paper on the preprint site ArXiv and soon to be published in the Astrophysical Journal, researchers present the first analysis of data from a new configuration of the MWA designed specifically to look for the signal of neutral hydrogen, the gas that dominated the universe during the cosmic dark age. The analysis sets a new limit -- the lowest limit yet -- for the strength of the neutral hydrogen signal.
"We can say with confidence that if the neutral hydrogen signal was any stronger than the limit we set in the paper, then the telescope would have detected it," said Jonathan Pober, an assistant professor of physics at Brown University and corresponding author on the new paper. "These findings can help us to further constrain the timing of when the cosmic dark ages ended and the first stars emerged."
The research was led by Wenyang Li, who performed the work as a Ph.D. student at Brown. Li and Pober collaborated with an international group of researchers working with the MWA.
Despite its importance in cosmic history, little is known about the period when the first stars formed, which is known as the Epoch of Reionization (EoR). The first atoms that formed after the Big Bang were positively charged hydrogen ions -- atoms whose electrons were stripped away by the energy of the infant universe. As the universe cooled and expanded, hydrogen atoms reunited with their electrons to form neutral hydrogen. And that's just about all there was in the universe until about 12 billion years ago, when atoms started clumping together to form stars and galaxies. Light from those objects re-ionized the neutral hydrogen, causing it to largely disappear from interstellar space.
The goal of projects like the one happening at MWA is to locate the signal of neutral hydrogen from the dark ages and measure how it changed as the EoR unfolded. Doing so could reveal new and critical information about the first stars -- the building blocks of the universe we see today. But catching any glimpse of that 12-billion-year-old signal is a difficult task that requires instruments with exquisite sensitivity.
When it began operating in 2013, the MWA was an array of 2,048 radio antennas arranged across the remote countryside of Western Australia. The antennas are bundled together into 128 "tiles," whose signals are combined by a supercomputer called the Correlator. In 2016, the number of tiles was doubled to 256, and their configuration across the landscape was altered to improve their sensitivity to the neutral hydrogen signal. This new paper is the first analysis of data from the expanded array.
Neutral hydrogen emits radiation at a wavelength of 21 centimeters. As the universe has expanded over the past 12 billion years, the signal from the EoR is now stretched to about 2 meters, and that's what MWA astronomers are looking for. The problem is there are myriad other sources that emit at the same wavelength -- human-made sources like digital television as well as natural sources from within the Milky Way and from millions of other galaxies.
"All of these other sources are many orders of magnitude stronger than the signal we're trying to detect," Pober said. "Even an FM radio signal that's reflected off an airplane that happens to be passing above the telescope is enough to contaminate the data."
To home in on the signal, the researchers use a myriad of processing techniques to weed out those contaminants. At the same time, they account for the unique frequency responses of the telescope itself.
"If we look at different radio frequencies or wavelengths, the telescope behaves a little differently," Pober said. "Correcting for the telescope response is absolutely critical for then doing the separation of astrophysical contaminants and the signal of interest."
Those data analysis techniques combined with the expanded capacity of the telescope itself resulted in a new upper bound of the EoR signal strength. It's the second consecutive best-limit-to-date analysis to be released by MWA and raises hope that the experiment will one day detect the elusive EoR signal.
Read more at Science Daily
Nov 25, 2019
A monkey's balancing act
The study, which looks specifically at the behaviour of an endangered monkey species, reveals that even in national parks where human presence is reduced and regulated, the animals carry out careful calculations and modify their natural behaviour to balance the pros and cons of living in close proximity to humans.
It reveals the negative impact that consuming human foods can have on the physical health of the monkeys, and highlights the need for new and sustainable conservation programmes to save the growing number of endangered species in their natural habitats.
Barbary macaques are an endangered species of monkeys restricted to the forests of Morocco and Algeria, with an introduced population also living on the Rock of Gibraltar. The wild population in North Africa has dramatically declined in the last decades.
The new study, led by Dr Bonaventura Majolo from the University of Lincoln, UK, involved a detailed examination of the effects of human activity on wild Barbary macaques in Ifrane National Park in Morocco.
Dr Majolo said: "When we observe animals in the wild we often talk about a 'landscape of fear'. This term refers to the decisions that animals make when they choose whether or not to avoid an area where the risk of predation is highest; weighing up the risk of attack against the possible rewards to be found there.
"Our study shows that macaques make many behavioural adjustments in response to varying levels of risk and reward, and that the way the macaques respond to human activity is very similar to the way in which they respond to predation risk. We see evidence here that the macaques are capable of great behavioural flexibility as they navigate the problems and the opportunities that sharing space with humans presents."
The researchers followed five groups of Barbary macaques and observed their behaviour and habitat selection over the course of a year. Their findings reveal the true extent of human activity on the monkeys' habitats and choices.
The researchers observed the macaques making significant adjustments to their behaviour and navigating their environment strategically in relation to human activity. They appear to balance food acquisition and risk avoidance -- for example they minimise risk by avoiding areas used by local shepherds and their dogs (which are now among the monkeys' most dangerous predators), and exploit opportunities to receive high-calorie human food by spending time close to roads.
Although being fed by humans may appear to be beneficial for the monkeys, food provisioning in fact has negative impacts on the macaques -- increasing their stress levels, heightening the probability of road injury and death, and having a detrimental impact on their health.
The monkeys' behaviour also shows seasonal trends in correlation with human activities. The macaques avoid herding routes during summer months, when herding activity by the local shepherds is at its peak, and they are more likely to use areas close to roads in the autumn and winter months, when natural food sources are low and the benefits of receiving high calorie human food may exceed the risk of being injured or even killed by road traffic.
The study reveals that the 'home range' of each observed macaque group (the area where a group of monkeys spend most of their time) included some kind of human structure, from roads and paths to picnic areas and farms. They also found that all of the study group's home ranges overlapped with at least one other, which the researchers conclude could be a result of declining availability of suitable habitats and food sources, or of direct competition over profitable areas close to roads and safe sleeping sites.
Their findings are published in the scientific journal Animal Conservation.
James Waterman, first author of the paper and a PhD student at Liverpool John Moores University, said: "Even in a national park, the effect of human disturbance on animal life can be considerable, and as our landscapes become increasingly human dominated, many wildlife species must cope with new ecological pressures. The impact of habitat loss and fragmentation, climate change, expanding human infrastructure, hunting and poaching quickly and dramatically alters habitats, forcing wildlife to adjust, move to more suitable areas (if these are available), or ultimately face the threat of extinction.
"This study highlights that it is more important than ever to develop conservation programs that take into account the requirements of all involved, including, but not limited to the wildlife that is ultimately at risk. Programs that fail to do so rarely produce lasting, positive change."
Read more at Science Daily
It reveals the negative impact that consuming human foods can have on the physical health of the monkeys, and highlights the need for new and sustainable conservation programmes to save the growing number of endangered species in their natural habitats.
Barbary macaques are an endangered species of monkeys restricted to the forests of Morocco and Algeria, with an introduced population also living on the Rock of Gibraltar. The wild population in North Africa has dramatically declined in the last decades.
The new study, led by Dr Bonaventura Majolo from the University of Lincoln, UK, involved a detailed examination of the effects of human activity on wild Barbary macaques in Ifrane National Park in Morocco.
Dr Majolo said: "When we observe animals in the wild we often talk about a 'landscape of fear'. This term refers to the decisions that animals make when they choose whether or not to avoid an area where the risk of predation is highest; weighing up the risk of attack against the possible rewards to be found there.
"Our study shows that macaques make many behavioural adjustments in response to varying levels of risk and reward, and that the way the macaques respond to human activity is very similar to the way in which they respond to predation risk. We see evidence here that the macaques are capable of great behavioural flexibility as they navigate the problems and the opportunities that sharing space with humans presents."
The researchers followed five groups of Barbary macaques and observed their behaviour and habitat selection over the course of a year. Their findings reveal the true extent of human activity on the monkeys' habitats and choices.
The researchers observed the macaques making significant adjustments to their behaviour and navigating their environment strategically in relation to human activity. They appear to balance food acquisition and risk avoidance -- for example they minimise risk by avoiding areas used by local shepherds and their dogs (which are now among the monkeys' most dangerous predators), and exploit opportunities to receive high-calorie human food by spending time close to roads.
Although being fed by humans may appear to be beneficial for the monkeys, food provisioning in fact has negative impacts on the macaques -- increasing their stress levels, heightening the probability of road injury and death, and having a detrimental impact on their health.
The monkeys' behaviour also shows seasonal trends in correlation with human activities. The macaques avoid herding routes during summer months, when herding activity by the local shepherds is at its peak, and they are more likely to use areas close to roads in the autumn and winter months, when natural food sources are low and the benefits of receiving high calorie human food may exceed the risk of being injured or even killed by road traffic.
The study reveals that the 'home range' of each observed macaque group (the area where a group of monkeys spend most of their time) included some kind of human structure, from roads and paths to picnic areas and farms. They also found that all of the study group's home ranges overlapped with at least one other, which the researchers conclude could be a result of declining availability of suitable habitats and food sources, or of direct competition over profitable areas close to roads and safe sleeping sites.
Their findings are published in the scientific journal Animal Conservation.
James Waterman, first author of the paper and a PhD student at Liverpool John Moores University, said: "Even in a national park, the effect of human disturbance on animal life can be considerable, and as our landscapes become increasingly human dominated, many wildlife species must cope with new ecological pressures. The impact of habitat loss and fragmentation, climate change, expanding human infrastructure, hunting and poaching quickly and dramatically alters habitats, forcing wildlife to adjust, move to more suitable areas (if these are available), or ultimately face the threat of extinction.
"This study highlights that it is more important than ever to develop conservation programs that take into account the requirements of all involved, including, but not limited to the wildlife that is ultimately at risk. Programs that fail to do so rarely produce lasting, positive change."
Read more at Science Daily
Bizarre worlds orbiting a black hole?
Theoreticians in two different fields defied the common knowledge that planets orbit stars like the Sun. They proposed the possibility of thousands of planets around a supermassive black hole.
"With the right conditions, planets could be formed even in harsh environments, such as around a black hole," says Keiichi Wada, a professor at Kagoshima University researching active galactic nuclei which are luminous objects energized by black holes.
According to the latest theories, planets are formed from fluffy dust aggregates in a protoplanetary disk around a young star. But young stars are not the only objects that possess dust disks. In a novel approach, the researchers focused on heavy disks around supermassive black holes in the nuclei of galaxies.
"Our calculations show that tens of thousands of planets with 10 times the mass of the Earth could be formed around 10 light-years from a black hole," says Eiichiro Kokubo, a professor at the National Astronomical Observatory of Japan who studies planet formation. "Around black holes there might exist planetary systems of astonishing scale."
Some supermassive black holes have large amounts of matter around them in the form of a heavy, dense disk. A disk can contain as much as a hundred thousand times the mass of the Sun worth of dust. This is a billion times the dust mass of a protoplanetary disk.
In a low temperature region of a protoplanetary disk, dust grains with ice mantles stick together and evolve into fluffy aggregates. A dust disk around a black hole is so dense that the intense radiation from the central region is blocked and low temperature regions are formed. The researchers applied the planet formation theory to circumnuclear disks and found that planets could be formed in several hundred million years.
Currently there are no techniques to detect these planets around black holes. However, the researchers expect this study to open a new field of astronomy.
From Science Daily
"With the right conditions, planets could be formed even in harsh environments, such as around a black hole," says Keiichi Wada, a professor at Kagoshima University researching active galactic nuclei which are luminous objects energized by black holes.
According to the latest theories, planets are formed from fluffy dust aggregates in a protoplanetary disk around a young star. But young stars are not the only objects that possess dust disks. In a novel approach, the researchers focused on heavy disks around supermassive black holes in the nuclei of galaxies.
"Our calculations show that tens of thousands of planets with 10 times the mass of the Earth could be formed around 10 light-years from a black hole," says Eiichiro Kokubo, a professor at the National Astronomical Observatory of Japan who studies planet formation. "Around black holes there might exist planetary systems of astonishing scale."
Some supermassive black holes have large amounts of matter around them in the form of a heavy, dense disk. A disk can contain as much as a hundred thousand times the mass of the Sun worth of dust. This is a billion times the dust mass of a protoplanetary disk.
In a low temperature region of a protoplanetary disk, dust grains with ice mantles stick together and evolve into fluffy aggregates. A dust disk around a black hole is so dense that the intense radiation from the central region is blocked and low temperature regions are formed. The researchers applied the planet formation theory to circumnuclear disks and found that planets could be formed in several hundred million years.
Currently there are no techniques to detect these planets around black holes. However, the researchers expect this study to open a new field of astronomy.
From Science Daily
Cannabis reduces headache and migraine pain by nearly half
Inhaled cannabis reduces self-reported headache severity by 47.3% and migraine severity by 49.6%, according to a recent study led by Carrie Cuttler, a Washington State University assistant professor of psychology.
The study, published online recently in the Journal of Pain, is the first to use big data from headache and migraine patients using cannabis in real time. Previous studies have asked patients to recall the effect of cannabis use in the past. There has been one clinical trial indicating that cannabis was better than ibuprofen in alleviating headache, but it used nabilone, a synthetic cannabinoid drug.
"We were motivated to do this study because a substantial number of people say they use cannabis for headache and migraine, but surprisingly few studies had addressed the topic," said Cuttler, the lead author on the paper.
In the WSU study, researchers analyzed archival data from the Strainprint app, which allows patients to track symptoms before and after using medical cannabis purchased from Canadian producers and distributors. The information was submitted by more than 1,300 patients who used the app over 12,200 times to track changes in headache from before to after cannabis use, and another 653 who used the app more than 7,400 times to track changes in migraine severity.
"We wanted to approach this in an ecologically valid way, which is to look at actual patients using whole plant cannabis to medicate in their own homes and environments," Cuttler said. "These are also very big data, so we can more appropriately and accurately generalize to the greater population of patients using cannabis to manage these conditions."
Cuttler and her colleagues saw no evidence that cannabis caused "overuse headache," a pitfall of more conventional treatments which can make patients' headaches worse over time. However, they did see patients using larger doses of cannabis over time, indicting they may be developing tolerance to the drug.
The study found a small gender difference with significantly more sessions involving headache reduction reported by men (90.0%) than by women (89.1%). The researchers also noted that cannabis concentrates, such as cannabis oil, produced a larger reduction in headache severity ratings than cannabis flower.
There was, however, no significant difference in pain reduction among cannabis strains that were higher or lower in levels of tetrahydrocannabinol (THC) and cannabidiol (CBD), two of the most commonly studied chemical constituents in cannabis, also known as cannabinoids. Since cannabis is made up of over 100 cannabinoids, this finding suggests that different cannabinoids or other constituents like terpenes may play the central role in headache and migraine relief.
More research is needed, and Cuttler acknowledges the limitations of the Strainprint study since it relies on a self-selected group of people who may already anticipate that cannabis will work to alleviate their symptoms, and it was not possible to employ a placebo control group.
Read more at Science Daily
The study, published online recently in the Journal of Pain, is the first to use big data from headache and migraine patients using cannabis in real time. Previous studies have asked patients to recall the effect of cannabis use in the past. There has been one clinical trial indicating that cannabis was better than ibuprofen in alleviating headache, but it used nabilone, a synthetic cannabinoid drug.
"We were motivated to do this study because a substantial number of people say they use cannabis for headache and migraine, but surprisingly few studies had addressed the topic," said Cuttler, the lead author on the paper.
In the WSU study, researchers analyzed archival data from the Strainprint app, which allows patients to track symptoms before and after using medical cannabis purchased from Canadian producers and distributors. The information was submitted by more than 1,300 patients who used the app over 12,200 times to track changes in headache from before to after cannabis use, and another 653 who used the app more than 7,400 times to track changes in migraine severity.
"We wanted to approach this in an ecologically valid way, which is to look at actual patients using whole plant cannabis to medicate in their own homes and environments," Cuttler said. "These are also very big data, so we can more appropriately and accurately generalize to the greater population of patients using cannabis to manage these conditions."
Cuttler and her colleagues saw no evidence that cannabis caused "overuse headache," a pitfall of more conventional treatments which can make patients' headaches worse over time. However, they did see patients using larger doses of cannabis over time, indicting they may be developing tolerance to the drug.
The study found a small gender difference with significantly more sessions involving headache reduction reported by men (90.0%) than by women (89.1%). The researchers also noted that cannabis concentrates, such as cannabis oil, produced a larger reduction in headache severity ratings than cannabis flower.
There was, however, no significant difference in pain reduction among cannabis strains that were higher or lower in levels of tetrahydrocannabinol (THC) and cannabidiol (CBD), two of the most commonly studied chemical constituents in cannabis, also known as cannabinoids. Since cannabis is made up of over 100 cannabinoids, this finding suggests that different cannabinoids or other constituents like terpenes may play the central role in headache and migraine relief.
More research is needed, and Cuttler acknowledges the limitations of the Strainprint study since it relies on a self-selected group of people who may already anticipate that cannabis will work to alleviate their symptoms, and it was not possible to employ a placebo control group.
Read more at Science Daily
Babies in the womb may see more than we thought
By the second trimester, long before a baby's eyes can see images, they can detect light.
But the light-sensitive cells in the developing retina -- the thin sheet of brain-like tissue at the back of the eye -- were thought to be simple on-off switches, presumably there to set up the 24-hour, day-night rhythms parents hope their baby will follow.
University of California, Berkeley, scientists have now found evidence that these simple cells actually talk to one another as part of an interconnected network that gives the retina more light sensitivity than once thought, and that may enhance the influence of light on behavior and brain development in unsuspected ways.
In the developing eye, perhaps 3% of ganglion cells -- the cells in the retina that send messages through the optic nerve into the brain -- are sensitive to light and, to date, researchers have found about six different subtypes that communicate with various places in the brain. Some talk to the suprachiasmatic nucleus to tune our internal clock to the day-night cycle. Others send signals to the area that makes our pupils constrict in bright light.
But others connect to surprising areas: the perihabenula, which regulates mood, and the amygdala, which deals with emotions.
In mice and monkeys, recent evidence suggests that these ganglion cells also talk with one another through electrical connections called gap junctions, implying much more complexity in immature rodent and primate eyes than imagined.
"Given the variety of these ganglion cells and that they project to many different parts of the brain, it makes me wonder whether they play a role in how the retina connects up to the brain," said Marla Feller, a UC Berkeley professor of molecular and cell biology and senior author of a paper that appeared this month in the journal Current Biology. "Maybe not for visual circuits, but for non-vision behaviors. Not only the pupillary light reflex and circadian rhythms, but possibly explaining problems like light-induced migraines, or why light therapy works for depression."
Parallel systems in developing retina
The cells, called intrinsically photosensitive retinal ganglion cells (ipRGCs), were discovered only 10 years ago, surprising those like Feller who had been studying the developing retina for nearly 20 years. She played a major role, along with her mentor, Carla Shatz of Stanford University, in showing that spontaneous electrical activity in the eye during development -- so-called retinal waves -- is critical for setting up the correct brain networks to process images later on.
Hence her interest in the ipRGCs that seemed to function in parallel with spontaneous retinal waves in the developing retina.
"We thought they (mouse pups and the human fetus) were blind at this point in development," said Feller, the Paul Licht Distinguished Professor in Biological Sciences and a member of UC Berkeley's Helen Wills Neuroscience Institute. "We thought that the ganglion cells were there in the developing eye, that they are connected to the brain, but that they were not really connected to much of the rest of the retina, at that point. Now, it turns out they are connected to each other, which was a surprising thing."
UC Berkeley graduate student Franklin Caval-Holme combined two-photon calcium imaging, whole-cell electrical recording, pharmacology and anatomical techniques to show that the six types of ipRGCs in the newborn mouse retina link up electrically, via gap junctions, to form a retinal network that the researchers found not only detects light, but responds to the intensity of the light, which can vary nearly a billionfold.
Gap junction circuits were critical for light sensitivity in some ipRGC subtypes, but not others, providing a potential avenue to determine which ipRGC subtypes provide the signal for specific non-visual behaviors that light evokes.
"Aversion to light, which pups develop very early, is intensity-dependent," suggesting that these neural circuits could be involved in light-aversion behavior, Caval-Holme said. "We don't know which of these ipRGC subtypes in the neonatal retina actually contributes to the behavior, so it will be very interesting to see what role all these different subtypes have."
The researchers also found evidence that the circuit tunes itself in a way that could adapt to the intensity of light, which probably has an important role in development, Feller said.
Read more at Science Daily
But the light-sensitive cells in the developing retina -- the thin sheet of brain-like tissue at the back of the eye -- were thought to be simple on-off switches, presumably there to set up the 24-hour, day-night rhythms parents hope their baby will follow.
University of California, Berkeley, scientists have now found evidence that these simple cells actually talk to one another as part of an interconnected network that gives the retina more light sensitivity than once thought, and that may enhance the influence of light on behavior and brain development in unsuspected ways.
In the developing eye, perhaps 3% of ganglion cells -- the cells in the retina that send messages through the optic nerve into the brain -- are sensitive to light and, to date, researchers have found about six different subtypes that communicate with various places in the brain. Some talk to the suprachiasmatic nucleus to tune our internal clock to the day-night cycle. Others send signals to the area that makes our pupils constrict in bright light.
But others connect to surprising areas: the perihabenula, which regulates mood, and the amygdala, which deals with emotions.
In mice and monkeys, recent evidence suggests that these ganglion cells also talk with one another through electrical connections called gap junctions, implying much more complexity in immature rodent and primate eyes than imagined.
"Given the variety of these ganglion cells and that they project to many different parts of the brain, it makes me wonder whether they play a role in how the retina connects up to the brain," said Marla Feller, a UC Berkeley professor of molecular and cell biology and senior author of a paper that appeared this month in the journal Current Biology. "Maybe not for visual circuits, but for non-vision behaviors. Not only the pupillary light reflex and circadian rhythms, but possibly explaining problems like light-induced migraines, or why light therapy works for depression."
Parallel systems in developing retina
The cells, called intrinsically photosensitive retinal ganglion cells (ipRGCs), were discovered only 10 years ago, surprising those like Feller who had been studying the developing retina for nearly 20 years. She played a major role, along with her mentor, Carla Shatz of Stanford University, in showing that spontaneous electrical activity in the eye during development -- so-called retinal waves -- is critical for setting up the correct brain networks to process images later on.
Hence her interest in the ipRGCs that seemed to function in parallel with spontaneous retinal waves in the developing retina.
"We thought they (mouse pups and the human fetus) were blind at this point in development," said Feller, the Paul Licht Distinguished Professor in Biological Sciences and a member of UC Berkeley's Helen Wills Neuroscience Institute. "We thought that the ganglion cells were there in the developing eye, that they are connected to the brain, but that they were not really connected to much of the rest of the retina, at that point. Now, it turns out they are connected to each other, which was a surprising thing."
UC Berkeley graduate student Franklin Caval-Holme combined two-photon calcium imaging, whole-cell electrical recording, pharmacology and anatomical techniques to show that the six types of ipRGCs in the newborn mouse retina link up electrically, via gap junctions, to form a retinal network that the researchers found not only detects light, but responds to the intensity of the light, which can vary nearly a billionfold.
Gap junction circuits were critical for light sensitivity in some ipRGC subtypes, but not others, providing a potential avenue to determine which ipRGC subtypes provide the signal for specific non-visual behaviors that light evokes.
"Aversion to light, which pups develop very early, is intensity-dependent," suggesting that these neural circuits could be involved in light-aversion behavior, Caval-Holme said. "We don't know which of these ipRGC subtypes in the neonatal retina actually contributes to the behavior, so it will be very interesting to see what role all these different subtypes have."
The researchers also found evidence that the circuit tunes itself in a way that could adapt to the intensity of light, which probably has an important role in development, Feller said.
Read more at Science Daily
The nature of salmonella is changing -- and it's meaner
Salmonella is acting up in Michigan, and it could be a model for what's happening in other states, according to a new Michigan State University study.
The study, appearing in Frontiers in Medicine, documents a substantial uptick in antibiotic resistant strains, and consequently, longer hospital stays as doctors work to treat the increasing virulent pathogens.
"If you get a salmonella infection that is resistant to antibiotics today, you are more likely to be hospitalized longer, and it will take you longer to recover," said Shannon Manning, MSU Foundation professor in the Department of Microbiology and Molecular Genetics and senior author of the study. "We need better detection methods at the clinical level to identify resistant pathogens earlier so we can treat them with the right drugs the first time."
Losing a day or more to misdiagnosis or improper treatment allows symptoms to get worse. Doctors might kill off a subpopulation of bacteria that are susceptible, but the ones that are resistant grow stronger, she added.
Salmonella is a diverse group of bacterial pathogens that causes foodborne infections. Infected patients often develop diarrhea, nausea, vomiting and abdominal pain, though some infections are more severe and can be life threatening.
When it comes to treatments, each strain reacts differently to the range of antibiotics available for prescription by doctors. So getting it right the first time is crucial.
Specifically in Michigan, doctors are seeing more strains that are resistant to ampicillin, a common antibiotic prescribed to treat salmonella. Multidrug resistance, or resistance to more than three classes of antibiotics, has also increased in Michigan and could further complicate patient treatment plans.
"We're still uncertain as to why this is happening; it could be that these antibiotics have been overprescribed in human and veterinary medicine and that possessing genes for resistance has allowed these bacteria to grow and thrive in the presence of antibiotics," Manning said. "Each state has its own antibiotic-resistance issues. It's important that the medical profession remains vigilant to ever-changing patterns of resistance in salmonella and other foodborne pathogens, rather than look for a blanket national solution."
Historically, salmonella has affected young children and the elderly, but now there's been a rise in adult cases, suggesting that the epidemiology of the infections has changed in Michigan.
Diving into individual strains of salmonella, the team of scientists found that patients with Typhimurium were more likely to have resistant infections as were patients infected during the fall, winter or spring months.
Another distinction was revealed between the strains affecting people living in rural and urban areas. Enteritis infections tend to be higher in rural areas. This may be attributed to rural residents' exposure to farm animals or untreated sources of water.
Each state's salmonella population has its own personality; so every state's approach to identifying disease drivers and effective treatments should be modified to reflect these traits.
Read more at Science Daily
The study, appearing in Frontiers in Medicine, documents a substantial uptick in antibiotic resistant strains, and consequently, longer hospital stays as doctors work to treat the increasing virulent pathogens.
"If you get a salmonella infection that is resistant to antibiotics today, you are more likely to be hospitalized longer, and it will take you longer to recover," said Shannon Manning, MSU Foundation professor in the Department of Microbiology and Molecular Genetics and senior author of the study. "We need better detection methods at the clinical level to identify resistant pathogens earlier so we can treat them with the right drugs the first time."
Losing a day or more to misdiagnosis or improper treatment allows symptoms to get worse. Doctors might kill off a subpopulation of bacteria that are susceptible, but the ones that are resistant grow stronger, she added.
Salmonella is a diverse group of bacterial pathogens that causes foodborne infections. Infected patients often develop diarrhea, nausea, vomiting and abdominal pain, though some infections are more severe and can be life threatening.
When it comes to treatments, each strain reacts differently to the range of antibiotics available for prescription by doctors. So getting it right the first time is crucial.
Specifically in Michigan, doctors are seeing more strains that are resistant to ampicillin, a common antibiotic prescribed to treat salmonella. Multidrug resistance, or resistance to more than three classes of antibiotics, has also increased in Michigan and could further complicate patient treatment plans.
"We're still uncertain as to why this is happening; it could be that these antibiotics have been overprescribed in human and veterinary medicine and that possessing genes for resistance has allowed these bacteria to grow and thrive in the presence of antibiotics," Manning said. "Each state has its own antibiotic-resistance issues. It's important that the medical profession remains vigilant to ever-changing patterns of resistance in salmonella and other foodborne pathogens, rather than look for a blanket national solution."
Historically, salmonella has affected young children and the elderly, but now there's been a rise in adult cases, suggesting that the epidemiology of the infections has changed in Michigan.
Diving into individual strains of salmonella, the team of scientists found that patients with Typhimurium were more likely to have resistant infections as were patients infected during the fall, winter or spring months.
Another distinction was revealed between the strains affecting people living in rural and urban areas. Enteritis infections tend to be higher in rural areas. This may be attributed to rural residents' exposure to farm animals or untreated sources of water.
Each state's salmonella population has its own personality; so every state's approach to identifying disease drivers and effective treatments should be modified to reflect these traits.
Read more at Science Daily
Nov 24, 2019
Science underestimated dangerous effects of sleep deprivation
Michigan State University's Sleep and Learning Lab has conducted one of the largest sleep studies to date, revealing that sleep deprivation affects us much more than prior theories have suggested.
Published in the Journal of Experimental Psychology: General, the research is not only one of the largest studies, but also the first to assess how sleep deprivation impacts placekeeping -- or, the ability to complete a series of steps without losing one's place, despite potential interruptions. This study builds on prior research from MSU's sleep scientists to quantify the effect lack of sleep has on a person's ability to follow a procedure and maintain attention.
"Our research showed that sleep deprivation doubles the odds of making placekeeping errors and triples the number of lapses in attention, which is startling," Fenn said. "Sleep-deprived individuals need to exercise caution in absolutely everything that they do, and simply can't trust that they won't make costly errors. Oftentimes -- like when behind the wheel of a car -- these errors can have tragic consequences."
By sharing their findings on the separate effects sleep deprivation has on cognitive function, Fenn -- and co-authors Michelle Stepan, MSU doctoral candidate and Erik Altmann, professor of psychology -- hope that people will acknowledge how significantly their abilities are hindered because of a lack of sleep.
"Our findings debunk a common theory that suggests that attention is the only cognitive function affected by sleep deprivation," Stepan said. "Some sleep-deprived people might be able to hold it together under routine tasks, like a doctor taking a patient's vitals. But our results suggest that completing an activity that requires following multiple steps, such as a doctor completing a medical procedure, is much riskier under conditions of sleep deprivation."
The researchers recruited 138 people to participate in the overnight sleep assessment; 77 stayed awake all night and 61 went home to sleep. All participants took two separate cognitive tasks in the evening: one that measured reaction time to a stimulus; the other measured a participant's ability to maintain their place in a series of steps without omitting or repeating a step -- even after sporadic interruptions. The participants then repeated both tasks in the morning to see how sleep-deprivation affected their performance.
"After being interrupted there was a 15% error rate in the evening and we saw that the error rate spiked to about 30% for the sleep-deprived group the following morning," Stepan said. "The rested participants' morning scores were similar to the night before.
"There are some tasks people can do on auto-pilot that may not be affected by a lack of sleep," Fenn said. "However, sleep deprivation causes widespread deficits across all facets of life."
From Science Daily
Published in the Journal of Experimental Psychology: General, the research is not only one of the largest studies, but also the first to assess how sleep deprivation impacts placekeeping -- or, the ability to complete a series of steps without losing one's place, despite potential interruptions. This study builds on prior research from MSU's sleep scientists to quantify the effect lack of sleep has on a person's ability to follow a procedure and maintain attention.
"Our research showed that sleep deprivation doubles the odds of making placekeeping errors and triples the number of lapses in attention, which is startling," Fenn said. "Sleep-deprived individuals need to exercise caution in absolutely everything that they do, and simply can't trust that they won't make costly errors. Oftentimes -- like when behind the wheel of a car -- these errors can have tragic consequences."
By sharing their findings on the separate effects sleep deprivation has on cognitive function, Fenn -- and co-authors Michelle Stepan, MSU doctoral candidate and Erik Altmann, professor of psychology -- hope that people will acknowledge how significantly their abilities are hindered because of a lack of sleep.
"Our findings debunk a common theory that suggests that attention is the only cognitive function affected by sleep deprivation," Stepan said. "Some sleep-deprived people might be able to hold it together under routine tasks, like a doctor taking a patient's vitals. But our results suggest that completing an activity that requires following multiple steps, such as a doctor completing a medical procedure, is much riskier under conditions of sleep deprivation."
The researchers recruited 138 people to participate in the overnight sleep assessment; 77 stayed awake all night and 61 went home to sleep. All participants took two separate cognitive tasks in the evening: one that measured reaction time to a stimulus; the other measured a participant's ability to maintain their place in a series of steps without omitting or repeating a step -- even after sporadic interruptions. The participants then repeated both tasks in the morning to see how sleep-deprivation affected their performance.
"After being interrupted there was a 15% error rate in the evening and we saw that the error rate spiked to about 30% for the sleep-deprived group the following morning," Stepan said. "The rested participants' morning scores were similar to the night before.
"There are some tasks people can do on auto-pilot that may not be affected by a lack of sleep," Fenn said. "However, sleep deprivation causes widespread deficits across all facets of life."
From Science Daily
Universal features of music around the world
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| Music festival |
The many musical styles of the world are so different, at least superficially, that music scholars are often sceptical that they have any important shared features. "Universality is a big word -- and a dangerous one," the great Leonard Bernstein once said. Indeed, in ethnomusicology, universality became something of a dirty word. But new research promises to once again revive the search for deep universal aspects of human musicality.
Samuel Mehr at Harvard University found that all cultures studied make music, and use similar kinds of music in similar contexts, with consistent features in each case. For example, dance music is fast and rhythmic, and lullabies soft and slow -- all around the world. Furthermore, all cultures showed tonality: building up a small subset of notes from some base note, just as in the Western diatonic scale. Healing songs tend to use fewer notes, and more closely spaced, than love songs. These and other findings indicate that there are indeed universal properties of music that likely reflect deeper commonalities of human cognition -- a fundamental "human musicality."
In a Science perspective piece in the same issue, University of Vienna researchers Tecumseh Fitch and Tudor Popescu comment on the implications. "Human musicality fundamentally rests on a small number of fixed pillars: hard-coded predispositions, afforded to us by the ancient physiological infrastructure of our shared biology. These 'musical pillars' are then 'seasoned' with the specifics of every individual culture, giving rise to the beautiful kaleidoscopic assortment that we find in world music," Tudor Popescu explains.
"This new research revives a fascinating field of study, pioneered by Carl Stumpf in Berlin at the beginning of the 20th century, but that was tragically terminated by the Nazis in the 1930s," Fitch adds.
As humanity comes closer together, so does our wish to understand what it is that we all have in common -- in all aspects of behaviour and culture. The new research suggests that human musicality is one of these shared aspects of human cognition. "Just as European countries are said to be 'United In Diversity', so too the medley of human musicality unites all cultures across the planet," concludes Tudor Popescu.
From Science Daily
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