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Using Ecstasy to treat PTSD: ‘I felt like my soul snapped back into place’

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Another drug shows great therapeutic promise, reported at PBS by Caleb Hellerman:

In nearly a decade trying to recover from post-traumatic stress disorder caused by childhood abuse, Jessi Appleton compiled a medical chart that reads like a Chinese restaurant menu. Biofeedback. Neurofeedback. Anti-depressants. Anti-anxiety medication. She tried a popular treatment called Eye Movement Desensitization and Reprocessing (EMDR), where she spent hours letting her gaze follow a therapist’s hand as it moved through carefully prescribed patterns. She tried another gaze-based therapy, called brainspotting.

“EMDR helped the most, but I was hitting a wall,” says Appleton. “I was suicidal. I was like this ghost sort of thing, walking through life. And I felt like nothing was going to change.”

Then she tried a new experimental treatment: therapy under the influence of MDMA, better known as Ecstasy. Her therapist suggested she sign up to be part of a pilot study. After three sessions, she said, “I felt like my soul snapped back into place.”

Appleton, 32, was treated in Boulder, Colorado, in a study arranged and funded by the Multidisciplinary Association for Psychedelic Studies (MAPS), an organization that has long pursued a strategy of supporting rigorous scientific research into otherwise illegal drugs.

On Tuesday, the Food and Drug Administration (FDA) gave the treatment an important boost, when agency officials met with officials from MAPS to start clearing the way for one or more large-scale research studies. According to Rick Doblin, MAPS’ founder and executive director, officials with the FDA’s Division of Psychiatry Products will not require additional studies prior to launching a Phase 3 trial, a critical round of testing that determines whether a medical treatment can be approved for widespread use.

“It was a very collaborative discussion, in light of the need to develop new treatments for PTSD for veterans and others,” Doblin says. “They recognize that this is a novel treatment, combining psychotherapy and pharmacotherapy, and there’s nothing else like it right now.”

The FDA says that federal law and internal regulations prohibit the agency from commenting on studies about pending applications or drugs still in development.

Details will be worked out over the next several months, but Doblin says that Phase 3 is likely to include at least 230 patients treated at roughly a dozen sites around the country.

Doblin and Appleton’s lead therapist, psychotherapist Marcela Ot’alora, say the therapy component is crucial. After a handful of preparatory meetings, the patient takes the drug under the watchful eyes of a two-person treatment team — almost always a man and a woman. Across studies, the dosage varies, but it is typically between 75 and 125mg, enough to trigger a strong experience. Like others, Appleton wore eyeshades and spent several hours lying back on a small couch, mostly in silence.

“It’s a lot of inner dialogue,” Appleton recalls. “Sometimes you’re terrified, sometimes relaxed, sometimes it’s other emotions. It’s intense, and by the end it’s exhausting.”

Ot’alora says her role is mostly supportive. Echoing Appleton’s description, she says the drug seems to help patients let go of their inner critic, or inner demons. “That part of you becomes a witness, saying, ‘This is what’s happening to you, this is what happened to you and this is how it felt.’ It’s very matter of fact.” . . .

Continue reading.

Read the whole thing. There’s quite a bit more.

Written by LeisureGuy

2 December 2016 at 12:45 pm

Ominous news: Tornado Outbreaks Are on the Rise, and Scientists Don’t Know Why

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It seems likely to me that large-scale changes in weather patterns are likely to be effects of global warming. And, since a majority of those in power (in the GOP, specifically) deny that global warming exists (and either cannot understand or refuse to consider, the evidence that it truly does exist, some of which—the disappearance of glaciers and the warming of the arctic and the rise in sea level—is totally obvious), I doubt that much will be done until it is too late, whereupon those who blocked action will blame the rest of us.

Grennan Milliken reports at Motherboard:

Late Tuesday and early Wednesday morning, a dozen tornadoes tore through the southern part of the US, killing 5 people and destroying up to 20 buildings in one town alone in Alabama.

This cluster of tornadoes, all part of one large weather-event, constitute a “tornado outbreak.” These are the most damaging and harmful tornado-related events that can occur. And new research, published today in Science, has found that the frequency and intensity of these deadly tornado outbreaks has nearly doubled in the last 50 years and may continue to do so. Whether these trends are related to climate change or not is unclear, and raises the question as to whether or not global warming may be affecting weather events in ways we don’t understand.

Comprehending how the most extreme tornado outbreaks function and form is a not just a matter of public health, but also a matter of financial security. The first half of 2016 in the U.S. saw $8.5 billion in insured losses due to tornadoes and severe thunderstorms. So a team of climate scientists led by Michael K. Tippett of Columbia University analyzed the most intense events on two National Oceanic and Atmospheric Administration datasets of tornadoes and meteorological observations related to tornado outbreaks from 1965 to 2015.

They found that the worst outbreaks are containing more tornadoes, and worse, that those outbreaks are growing in intensity faster than the “regular sized” ones. But they can’t determine why this is happening.

Climate change is one guess, but the researchers haven’t found any conclusive signs that it is the culprit. Lead author Michael Tippett told Motherboard that climate models are good for predicting temperature rise, but they can’t say how weather will change. So scientists act like weather forecasters. They look for environments that are favorable to severe storms, and then see if climate change is likely to create more of those storm-friendly environments.

“If it’s climate change, well—we can expect more,” Tippett said. “That’s the bad news scenario. And the good news scenario is if it’s not climate change then we could go back to the way it was earlier. The 80s, let’s say.”

One of the main ingredients for tornadoes, thunderstorms and the like is something called convective available potential energy (CAPE), which refers to warm moist air near the ground surface that ultimately rises up into the atmosphere. Climate projections have said that increases in CAPE will cause more frequent storm-friendly environments, explained Tippett.

But despite the increase in the intensity of tornado outbreaks, “we don’t see these extreme CAPE environments changing” he said. “It’s either not climate change, or it’s something about climate change that we don’t understand.”

Tippett also pointed out that lots of aspects of climate change are unknown. . .

Continue reading.

Written by LeisureGuy

2 December 2016 at 10:57 am

Magic mushrooms ease anxiety and depression in cancer patients in one dose

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Melissa Healy reports the good news in the LA Times:

In findings that could pry open a door closed for nearly half a century, researchers have found that psilocybin — a hallucinogen long used in traditional healing rituals — eases the depression and soothes the anxiety of patients contending with serious illness and the prospect of imminent death.

In two separate studies published Thursday, researchers report that trial subjects who received a single moderate-to-large dose of psilocybin got substantial and lasting relief from their profound distress. Among 80 cancer patients who participated in the two trials, as many as 4 in 5 continued to feel measurably less hopeless and demoralized six months after taking the drug than they had upon their recruitment.

And even years later, many reported they had gained — and retained — a profound sense of peace and meaning from the experience. Of 29 cancer patients who got psilocybin in a trial conducted at New York University’s Langone Medical Center, 20 rated it as “among the most meaningful” events of their life.

“This drug saved my life and changed my life,” said Dinah Bazer, a Brooklyn, N.Y., woman who was administered a single dose of psilocybin at a New York treatment center in 2011.

In the wake of treatment for ovarian cancer, Bazer said, her anxiety at the prospect of its return was “eating her alive.” Under the influence of a single high dose of psilocybin, Bazer said Wednesday, she became “volcanically angry” as she visualized her cancer as a dark mass bearing down on her. With an epithet, she then saw herself throwing it off.

“I was bathed in God’s love” for hours after that, said Bazer, who describes herself as an atheist. When the psilocybin’s hallucinatory effects wore off, she said, two years of intense anxiety were simply gone.

“This is a groundbreaking result,” said Dr. George Greer, medical director of the Heffter Research Institute, the nonprofit organization that funded the two trials.

Greer suggested that the “existential anxiety” of the terminally ill is only one of many conditions that psilocybin may one day treat. Others may include treatment-resistant depression, addiction to cocaine, alcohol or tobacco, obsessive-compulsive disorder and “demoralization” in long-term survivors of HIV, he said.

Johns Hopkins University psychiatrist Dr. Roland R. Griffiths, the lead author of one of the two studies, said the enduring relief provided by a single dose of psilocybin makes such treatment more akin to surgery than it does to the plodding, labor-intensive treatments that remain the mainstay of his profession.

“I really don’t think we have any models in psychiatry that look like” the effects demonstrated in the two trials, said Griffiths. “Something occurs and it’s repaired and it’s better going forward … very plausibly for more than six months,” he added. “In that sense it’s a new model.”

The publication of the two early trials, in the Journal of Psychopharmacology, marks an American return to research on the therapeutic use of hallucinogenic drugs after a hiatus of 50 years.

In the 1950s and ’60s, hallucinogenic drugs such as lysergic acid diethylamide — LSD — and psilocybin, which is found naturally in certain mushrooms, were widely used in U.S. biomedical research and in psychotherapy practices. But in 1966, as the psychedelic drugs gained a broad counterculture following in the United States, the U.S. government declared any use of the drugs illegal. By the 1970s, that ended all American research on their potential therapeutic benefits.

In recent years, a small clutch of American researchers, including the authors of the two new papers, have argued that such prohibitions might be preventing the discovery of better treatments for widespread and pressing psychiatric problems, including depression, addiction and post-traumatic stress disorder (PTSD).

With PTSD epidemic among U.S. combat veterans and drug addiction a national scourge, American officials have indicated a new willingness to allow research to proceed on psychedelic and other drugs long classified as having no legitimate medical use.

On Tuesday, the Food and Drug Administration gave its blessing to conducting large-scale clinical trials of an experimental medication  — 3,4-methylenedioxymethamphetamine — better known as the party drug ecstasy.

Like LSD and psilocybin, ecstasy appears to hold promise as an adjunct to psychotherapy in the treatment of PTSD. If the resulting Phase 3 trials of ecstasy demonstrate their effectiveness, the next step could be FDA approval of ecstasy as a prescription drug. . .

Continue reading.

The War on Drugs that Nixon initiated (against the advice of a presidential commission he formed) has done incalculable damage and blocked for decades the discovery of the benefits the drugs might bring. And I fear with Jeff Sessions as Attorney General we in for a big regression.

Later in the column:

In one of the trials, researchers used a very low dose of psilocybin, much lower than that required to induce hallucinations, as a placebo. In the other, they used the dietary supplement niacin. In each trial, all of the subjects got a high dose of psilocybin in one of two sessions. So all, in the end, experienced the full effects of the drug.

All subjects in both trials had been diagnosed with cancer, and with “existential anxiety or depression” resulting from the illness and the likelihood of an early death. Participants were extensively prepared for the expected effects of the psilocybin. To minimize adverse reactions, researchers closely monitored the subjects while they were under the influence of the drug or the placebo. Afterwards, psychotherapists encouraged the subjects to write down and reflect upon the experience.

Immediately after, as well as five weeks after their first session, subjects who got the psilocybin first looked much better than did those who got the placebo first. A wide range of standardized measures of depression, anxiety and quality of life showed that these subjects were less hopeless, less demoralized and less anxious.

Six months out, 87% of those in the trial conducted at New York University/Langone reported their life satisfaction and/or well-being had been improved by the experience. In the larger of the two trials, conducted at Johns Hopkins University, psilocybin produced “large and significant … increases in measures of quality of life, life meaning, death acceptance, and optimism” — effects that “were sustained at six months.”

Psilocybin’s side effects, meanwhile, were pretty tame. In the two trials, about 15% of subjects experienced nausea or vomiting when getting a high dose, and about 1 in 3 experienced some form of transient psychological discomfort. Many subjects’ heart rates and blood pressure rose, but none to a dangerous extent.

The potential use of psilocybin in patients diagnosed with life-threatening diseases comes at a moment when medical care at the end of life is a subject of growing concern among patients and physicians. Research finds it’s still common for dying patients to get painful and futile procedures. Palliative and hospice care, both aimed at easing the discomfort of the seriously ill, are growing specialties in American hospitals. An increasing number of patients, meanwhile, are demanding the right to die with a physician’s help.

As states debate these physician-assisted suicide bills, they should consider the implications of finding an effective treatment for the “existential distress” of the dying, said Dr. Craig D. Blinderman, a palliative care specialist at Columbia University Medical Center/New York Presbyterian Hospital.

And there’s a lot more. Worth reading.

Written by LeisureGuy

2 December 2016 at 10:47 am

Cognitive closure and US politics

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That’s from a very interesting Open Culture post by Dan Colman, which begins:

There’s a political disconnect in the United States. We have two political parties, each now living in its own reality and working with its own set of facts. The common ground between them? Next to none.

How to explain this disconnect? Maybe the answer lies in the theory of “cognitive closure”–a theory first worked out by social psychologist Arie Kruglanski back in 1989.

“People’s politics are driven by their psychological needs,” Kruglanski explains in the short documentary above. “People who are anxious because of the uncertainty that surrounds them are going to be attracted to messages that offer certainty.”

He sips a soda, then continues, . . .

But watch the documentary. It’s just 7 minutes.

Written by LeisureGuy

1 December 2016 at 6:12 pm

The Case Against Dark Matter

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Natalie Wolchover reports in Quanta:

For 80 years, scientists have puzzled over the way galaxies and other cosmic structures appear to gravitate toward something they cannot see. This hypothetical “dark matter” seems to outweigh all visible matter by a startling ratio of five to one, suggesting that we barely know our own universe. Thousands of physicists are doggedly searching for these invisible particles.

But the dark matter hypothesis assumes scientists know how matter in the sky ought to move in the first place. This month, a series of developments has revived a long-disfavored argument that dark matter doesn’t exist after all. In this view, no missing matter is needed to explain the errant motions of the heavenly bodies; rather, on cosmic scales, gravity itself works in a different way than either Isaac Newton or Albert Einstein predicted.

The latest attempt to explain away dark matter is a much-discussed proposal by Erik Verlinde, a theoretical physicist at the University of Amsterdam who is known for bold and prescient, if sometimes imperfect, ideas. In a dense 51-page paper posted online on Nov. 7, Verlinde casts gravity as a byproduct of quantum interactions and suggests that the extra gravity attributed to dark matter is an effect of “dark energy” — the background energy woven into the space-time fabric of the universe.

Instead of hordes of invisible particles, “dark matter is an interplay between ordinary matter and dark energy,” Verlinde said.

To make his case, Verlinde has adopted a radical perspective on the origin of gravity that is currently in vogue among leading theoretical physicists. Einstein defined gravity as the effect of curves in space-time created by the presence of matter. According to the new approach, gravity is an emergent phenomenon. Space-time and the matter within it are treated as a hologram that arises from an underlying network of quantum bits (called “qubits”), much as the three-dimensional environment of a computer game is encoded in classical bits on a silicon chip. Working within this framework, Verlinde traces dark energy to a property of these underlying qubits that supposedly encode the universe. On large scales in the hologram, he argues, dark energy interacts with matter in just the right way to create the illusion of dark matter.

In his calculations, Verlinde rediscovered the equations of “modified Newtonian dynamics,” or MOND. This 30-year-old theory makes an ad hoc tweak to the famous “inverse-square” law of gravity in Newton’s and Einstein’s theories in order to explain some of the phenomena attributed to dark matter. That this ugly fix works at all has long puzzled physicists. “I have a way of understanding the MOND success from a more fundamental perspective,” Verlinde said.

Many experts have called Verlinde’s paper compelling but hard to follow. While it remains to be seen whether his arguments will hold up to scrutiny, the timing is fortuitous. In a new analysis of galaxies published on Nov. 9 in Physical Review Letters, three astrophysicists led by Stacy McGaugh of Case Western Reserve University in Cleveland, Ohio, have strengthened MOND’s case against dark matter.

The researchers analyzed a diverse set of 153 galaxies, and for each one they compared the rotation speed of visible matter at any given distance from the galaxy’s center with the amount of visible matter contained within that galactic radius. Remarkably, these two variables were tightly linked in all the galaxies by a universal law, dubbed the “radial acceleration relation.” This makes perfect sense in the MOND paradigm, since visible matter is the exclusive source of the gravity driving the galaxy’s rotation (even if that gravity does not take the form prescribed by Newton or Einstein). With such a tight relationship between gravity felt by visible matter and gravity given by visible matter, there would seem to be no room, or need, for dark matter.

Even as dark matter proponents rise to its defense, a third challenge has materialized. In new research that has been presented at seminars and is under review by the Monthly Notices of the Royal Astronomical Society, a team of Dutch astronomers have conducted what they call the first test of Verlinde’s theory: In comparing his formulas to data from more than 30,000 galaxies, Margot Brouwer of Leiden University in the Netherlands and her colleagues found that Verlinde correctly predicts the gravitational distortion or “lensing” of light from the galaxies — another phenomenon that is normally attributed to dark matter. This is somewhat to be expected, as MOND’s original developer, the Israeli astrophysicist Mordehai Milgrom, showed years ago that MOND accounts for gravitational lensing data. Verlinde’s theory will need to succeed at reproducing dark matter phenomena in cases where the old MOND failed.

Kathryn Zurek, a dark matter theorist at Lawrence Berkeley National Laboratory, said Verlinde’s proposal at least demonstrates how something like MOND might be right after all. “One of the challenges with modified gravity is that there was no sensible theory that gives rise to this behavior,” she said. “If [Verlinde’s] paper ends up giving that framework, then that by itself could be enough to breathe more life into looking at [MOND] more seriously.”

The New MOND

In Newton’s and Einstein’s theories, the gravitational attraction of a massive object drops in proportion to the square of the distance away from it. This means stars orbiting around a galaxy should feel less gravitational pull — and orbit more slowly — the farther they are from the galactic center. Stars’ velocities do drop as predicted by the inverse-square law in the inner galaxy, but instead of continuing to drop as they get farther away, their velocities level off beyond a certain point. The “flattening” of galaxy rotation speeds, discovered by the astronomer Vera Rubin in the 1970s, is widely considered to be Exhibit A in the case for dark matter — explained, in that paradigm, by dark matter clouds or “halos” that surround galaxies and give an extra gravitational acceleration to their outlying stars.

Searches for dark matter particles have proliferated — with hypothetical “weakly interacting massive particles” (WIMPs) and lighter-weight “axions” serving as prime candidates — but so far, experiments have found nothing.

Meanwhile, in the 1970s and 1980s, some researchers, including Milgrom, took a different tack. . .

Continue reading.

Written by LeisureGuy

1 December 2016 at 11:41 am

Posted in Science

In the Deep, Clues to How Life Makes Light

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Steph Yin reports in Quanta:

Dive deep enough under the surface of the ocean, and light reigns. Some 90 percent of the fish and crustaceans that dwell at depths of 100 to 1,000 meters are capable of making their own light. Flashlight fish hunt and communicate with a flashing Morse code sent by light pockets that pulse under their eyes. Tubeshoulder fish shoot luminous ink at their attackers. Hatchetfish make themselves appear invisible by generating light on their underbellies to mimic downwelling sunlight; predators prowling below look up to see only a continuous glow.

Scientists have indexed thousands of bioluminescent organisms across the tree of life, and they expect to add many more. Yet researchers have long wondered how bioluminescence came to be. Now, as explained in several recently released studies, researchers have made significant progress in understanding the origins of bioluminescence — both evolutionary and chemical. The new understanding may one day allow bioluminescence to be used as a tool in biology and medical research.

One longstanding challenge has been determining how many separate times bioluminescence arose. How many species came to the same conclusion, independent of one another?

Though some of the most familiar examples of light from living organisms are terrestrial — think of fireflies, glowworms and foxfire — the bulk of evolutionary events involving bioluminescence took place in the ocean. Bioluminescence is in fact markedly absent from all terrestrial vertebrates and flowering plants.

In the deep ocean, light gives organisms a unique way to attract prey, communicate and defend themselves, said Matthew Davis, a biologist at St. Cloud State University in Minnesota. In a study released in June, he and his colleagues found that fish that use light for communication and courtship signaling were especially diverse. Over a period of about 150 million years — brief by evolutionary standards —such fish proliferated into more species than other groups of fish. Bioluminescent species that used their light exclusively for camouflage, on the other hand, were no more diverse.

Courtship signals can change relatively easily. These changes can in turn create subgroups in a population, which eventually split into unique species. In June, Todd Oakley, an evolutionary biologist at the University of California, Santa Barbara, and one of his students, Emily Ellis, published a study in which they found that organisms that use bioluminescence in courtship had significantly more species, and faster rates of species accumulation, than closely related organisms that do not use light. Oakley and Ellis studied ten groups of organisms, including fireflies, octopuses, sharks and tiny crustaceans called ostracods.

The study by Davis and his colleagues was limited to ray-finned fishes, a group that includes approximately 95 percent of fish species. Davis estimated that even in that single group, bioluminescence evolved at least 27 times. Steven Haddock, a marine biologist at the Monterey Bay Aquarium Research Institute and an expert on bioluminescence, estimated that across all life forms bioluminescence evolved independently at least 50 times.

Many Ways to Glow

In nearly all shining organisms, bioluminescence requires three ingredients: oxygen, a light-emitting pigment called a luciferin (from the Latin word lucifer, meaning light-bringing), and an enzyme called a luciferase. When a luciferin reacts with oxygen — a process facilitated by luciferase — it forms an excited, unstable compound that emits light when it returns to its lowest energy state.

Curiously, there are far fewer luciferins than luciferases. While species tend to have unique luciferases, many share the same luciferin. Just four luciferins are responsible for most of the light production in the ocean. Of close to 20 groups of bioluminescent organisms in the world, a luciferin called coelenterazine is the light-emitter in nine.

Yet it would be a mistake to assume that all coelenterazine-containing organisms had evolved from a single luminous ancestor. If they had, asked Warren Francis, a biologist at Ludwig Maximilian University in Munich, then why did they develop such a wide variety of luciferases? Presumably the first luciferin-luciferase pair would have survived and multiplied.

It’s more likely that many of these species don’t make coelenterazine themselves. Instead, they get it from their diet, said Yuichi Oba, a professor of biology at Chubu University in Japan.

In 2009, a group led by Oba discovered that the deep-sea copepod — a tiny, near-ubiquitous crustacean — makes its own coelenterazine. These copepods are an extremely abundant food source for a wide range of marine animals — so much so that “in Japan, we call copepods ‘rice in the ocean,’” Oba said. He thinks copepods are key to understanding why so many marine organisms are bioluminescent.

Oba and his colleagues took amino acids believed to be the building blocks of coelenterazine, labeled them with a molecular marker, and loaded them into copepod food. They then fed this food to copepods in the lab.

After 24 hours, the researchers extracted coelenterazine from the copepods and looked for the labels they had added. Sure enough, the labels were there — definitive proof that the crustaceans had synthesized luciferin molecules from the amino acids.

Even the jellyfish in which coelenterazine was first discovered (and named after) was later found not to produce its own coelenterazine at all. It obtains its luciferin by eating copepods and other small crustaceans.

Mysterious Origins

Researchers have found another clue that might help explain the popularity of coelenterazine in deep-sea animals: the molecule also exists in organisms that don’t emit light. This struck Jean-François Rees, a biologist at the Catholic University of Louvain, in Belgium, as odd. It’s already surprising “that so many different animals rely on exactly the same molecule for producing light,” he said. Perhaps coelenterazine had another function besides luminescence?

In experiments with rat liver cells, Rees showed that coelenterazine is a powerful antioxidant.

Many Ways to Glow

In nearly all shining organisms, bioluminescence requires three ingredients: oxygen, a light-emitting pigment called a luciferin (from the Latin word lucifer, meaning light-bringing), and an enzyme called a luciferase. When a luciferin reacts with oxygen — a process facilitated by luciferase — it forms an excited, unstable compound that emits light when it returns to its lowest energy state.

Curiously, there are far fewer luciferins than luciferases. While species tend to have unique luciferases, many share the same luciferin. Just four luciferins are responsible for most of the light production in the ocean. Of close to 20 groups of bioluminescent organisms in the world, a luciferin called coelenterazine is the light-emitter in nine.

Yet it would be a mistake to assume that all coelenterazine-containing organisms had evolved from a single luminous ancestor. If they had, asked Warren Francis, a biologist at Ludwig Maximilian University in Munich, then why did they develop such a wide variety of luciferases? Presumably the first luciferin-luciferase pair would have survived and multiplied.

It’s more likely that many of these species don’t make coelenterazine themselves. Instead, they get it from their diet, said Yuichi Oba, a professor of biology at Chubu University in Japan.

In 2009, a group led by Oba discovered that the deep-sea copepod — a tiny, near-ubiquitous crustacean — makes its own coelenterazine. These copepods are an extremely abundant food source for a wide range of marine animals — so much so that “in Japan, we call copepods ‘rice in the ocean,’” Oba said. He thinks copepods are key to understanding why so many marine organisms are bioluminescent.

Oba and his colleagues took amino acids believed to be the building blocks of coelenterazine, labeled them with a molecular marker, and loaded them into copepod food. They then fed this food to copepods in the lab.

After 24 hours, the researchers extracted coelenterazine from the copepods and looked for the labels they had added. Sure enough, the labels were there — definitive proof that the crustaceans had synthesized luciferin molecules from the amino acids.

Even the jellyfish in which coelenterazine was first discovered (and named after) was later found not to produce its own coelenterazine at all. It obtains its luciferin by eating copepods and other small crustaceans.

Mysterious Origins

Researchers have found another clue that might help explain the popularity of coelenterazine in deep-sea animals: the molecule also exists in organisms that don’t emit light. This struck Jean-François Rees, a biologist at the Catholic University of Louvain, in Belgium, as odd. It’s already surprising “that so many different animals rely on exactly the same molecule for producing light,” he said. Perhaps coelenterazine had another function besides luminescence?

In experiments with rat liver cells, Rees showed that coelenterazine is a powerful antioxidant. . .

Continue reading.

Written by LeisureGuy

1 December 2016 at 10:49 am

Posted in Evolution, Science

An overview of physics today

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Very interesting video:

Written by LeisureGuy

30 November 2016 at 11:17 am

Posted in Science, Video

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