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The Food and Drug Administration approved a novel antidepressant late Tuesday for people with depression that does not respond to other treatments – the first in decades to work in a completely new way in the brain.

The drug, a nasal spray called esketamine, has been eagerly anticipated by psychiatrists and patient groups as a powerful new tool to fight intractable depression.

The spray acts within hours, rather than weeks or months as is typical for current antidepressants, and could offer a lifeline to about 5 million people in the United States with major depressive disorder who haven’t been helped by current treatments. That accounts for about 1 in 3 people with depression.

“This is undeniably a major advance,” said Jeffrey Lieberman, a Columbia University psychiatrist. But he cautioned much is still unknown about the drug, particularly regarding its long-term use.

“Doctors will have to be very judicious and feel their way along,” he said.

The label for the drug will carry a black box warning – the most serious safety warning issued by the FDA. It will caution users they could experience sedation and problems with attention, judgment and thinking, and that there’s potential for abuse and suicidal thoughts.

People who take esketamine will have to be monitored for at least two hours after receiving a dose to guard against some of these side effects.

The medicine has a complex legacy because it is a component of ketamine, which was approved years ago as an anesthetic and was once popular as a party drug called Special K.

Esketamine must be administered under medical supervision and can only be used in a certified doctor’s office or clinic, according to the conditions of the FDA approval. It is to be taken with an oral antidepressant.

For some patients who have searched for a depression treatment for years, the results of ketamine treatment have been profound.

Dennis Charney, dean of the Icahn School of Medicine at Mount Sinai Health System in New York, did extensive early work to show ketamine was an effective treatment. In 2000, he and other researchers published the first study showing that intravenous ketamine rapidly relieved depression.

After giving IV ketamine to seven patients, “to our surprise, they started saying within a few hours that they felt better,” Charney said. “It was a wonderful shock.”

That was the experience of Michael Wurst of Secaucus, NJ. Wurst, 37, has suffered from depression as far back as he can remember, but only sought therapy and medication in college.

He had a negative experience with an oral antidepressant and stopped treatment. Later, when he decided to get help again, he was reluctant to try medication but eventually spent a decade cycling through various drugs and combinations, none of which helped.

Then, two years ago, he began receiving ketamine as part of a clinical trial. The first three treatments had no effect, but the fourth “was like a goddamn miracle, like someone just turned the light switch on,” Wurst said.

“It was like the weight in my head, the cloud that was there for decades, just disappeared. It changed the entire course of my life.”

Wurst said he feels like he’s been given back his future. He and his wife just bought a house and he’s no longer afraid to think about having children.

“This offers hope, in capital letters,” said Charney, who is a co-inventor on a patent on the use of ketamine as a depression treatment that has been licensed by Johnson & Johnson.

Esketamine, the drug Johnson & Johnson received approval to sell, will appear under the brand name Spravato.

The company opted for a nasal spray after concluding that IV administration was impractical and a pill wouldn’t get enough of the drug to the brain, according to David Hough, the esketamine team leader at Janssen Research & Development, which is part of Johnson & Johnson.

Lee Hoffer, a medical anthropologist at Case Western Reserve University who studies addiction and the use of illicit drugs, was a member of the FDA advisory committee that recommended last month that the drug be approved.

He said that ketamine was a club drug used mainly in the 1990s and 2000s, and can have powerful effects, including hallucinations, tunnel vision and dissociative effects that make people feel untethered from their surroundings.

Despite the fact that ketamine can have euphoric effects, Hoffer said he is not very concerned about abuse because of safety measures that will be put in place. Unlike a prescription that can be taken home and might be diverted into recreational use, esketamine will be administered under supervision.

He also noted that although ketamine has been available for decades and has been used off-label to treat depression, he hasn’t encountered people who now use the drug recreationally in his research and interviews with illicit drug users.

“There are risks associated with the drug, but I think the benefits here probably outweigh those,” Hoffer said.

The FDA advisory committee voted 14-2 in February to recommend approval of the drug. That’s despite the fact that the evidence was more mixed than for other approved antidepressants, according to a report by agency staff.

Typical antidepressants are approved on the basis of two positive short-term trials, but there was only one such trial for esketamine.

The second trial considered in support of the drug was a withdrawal study, and FDA said its division of psychiatry products had not previously considered such a study as one of the primary pieces of evidence for an approval.

Kim Witczak, a consumer representative on the advisory committee who voted against approval said she was concerned about the safety risks balanced against the “extremely limited positive clinical trial results” in a blog post.

“At the end of the day, safety will always be my top priority and I didn’t feel this was similarly the case for the manufacturer as it rushed this esketamine nasal spray to market,” Witczak wrote.

Hough said patients would receive the treatment two times a week for a month, then every week and then every other week, along with an oral antidepressant.

Whether a patient stays on the drug for more than six months or a year will be up to the patient and his or her doctor, he said.

The list price of the drug will be US$590 to US$885 per treatment session based on the dosage taken, which will vary between patients.

During the first month of therapy, that would add up to a price in the range of US$4,720 to US$6,785. After the first month, maintenance therapy could range from US$2,360 to US$3,540.

Many clinics have sprung up to offer IV ketamine to people off-label, but those treatments are typically paid out-of-pocket, while esketamine is more likely to be covered by insurance with the agency’s approval.

Older antidepressants target the neurotransmitters serotonin, norepinephrine or dopamine. Esketamine affects the receptor for a different brain chemical called glutamate.

Gerard Sanacora, a professor of psychiatry at Yale University School of Medicine, who has led studies sponsored by Janssen and accepted consulting payments from the company, said the esketamine results have already begun to invigorate the broader field of developing psychiatric drugs.

A decade ago, he noted, companies began to abandon the effort.

“Everything that was coming out was another me-too antidepressant, and anything that was truly novel wasn’t able to show clinical benefit,” Sanacora said. “It’s really opened a whole new vista of opportunities.”

2019 © The Washington Post

This article was originally published by The Washington Post.

The post The FDA Has Approved A New Ketamine-Based Nasal Spray For Depression appeared first on Science Afrique.

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Microdosing DMT

The idea of taking small doses of psychedelic drugs has gained cachet in recent years, especially in the world of tech startups, where practitioners believe it can enhance creativity and fight depression.

Now, new research shows that microdosing DMT — taking doses of the drug that are too low to cause hallucinations — could indeed reduce symptoms of depression and anxiety, according to The Atlantic — and though data is still scarce, the work could pave the way to new mental health treatments.

Rats Vs Humans!

An important caveat to the new research, which was published Monday in the journal ACS Chemical Neuroscience: its subjects were rats, not people.

But David Olson, a chemist and neuroscientist at the University of California at Davis, thinks his team’s study is important nonetheless because it provides some of the first evidence that there are benefits to taking psychedelic drugs below a dosage threshold that would cause you to, well, trip.

“I really wanted to answer the question as to whether or not the hallucinogenic effects of these compounds were necessary for the therapeutic effects,” he told The Atlantic.

Cytotoxic Effects

Still, before you start microdosing DMT at work, it’s probably worth waiting for more data. In some rats, Olson’s team found, the DMT appeared to have “cytotoxic effects” that killed brain cells. At the very least, more research is needed.

“There’s that saying,” Olson told The Atlantic, “that the difference between a medicine and a poison is the dose.”

This article was republished from Futurism. Read the original article here.

The post New Study Shows ‘Microdosing DMT’ Reduces Depression and Anxiety appeared first on Science Afrique.

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Your bags are packed, your rooms are booked, you’re all set for your vacation; there’s just one problem, the government has canceled your tickets.

As early as 2014, China began conceptualizing a Social Credit System (SCS), sort of like a credit score for citizen behavior where behaviors deemed good for society are rewarded with privileges and bad behaviors result in a poor score and loss of privileges.

China has since been working to test its new method of population control and has been slowly conscripting citizens into the system.

Now, a new report acquired by the Associated Press, suggests millions of would-be travelers had their plans canceled as a result of the SCS in 2018.

According to the report obtained by the Associated Press, as many as 17.5 million ticket purchases were blocked last year for “social credit offenses” such as unpaid taxes or fines.

Other would-be travelers were barred from purchasing train tickets as many as 5.5 million times and according to an annual report from the National Public Credit Information Center, as many as 138 people were stopped from leaving the country.

The ruling party hopes to fully establish the system within the nation by 2020. Although it isn’t completely clear yet how the system will be maintained, what the SCS will penalize, and what penalties there may be for having “poor social credit”, offenses penalized last year included everything from false advertising to drug charges.

In addition to travel restrictions, companies ousted from the nation’s good graces can lose out on government contracts, bank loans, and be restricted from importing goods.

Employees can be prevented from representing companies or taking senior management roles, a penalty which was applied 290,000 times last year.

The SCS is just one part of the way President Xi Jinping’s government plans to use technology and data systems to monitor and control its citizens.

Part of a decade long ambition known as The Golden Shield Project, new surveillance technologies are being rolled out constantly and include things such as glasses with facial recognition capabilities for law enforcement, gait recognition software, and productivity monitoring programs so efficient employees are convinced employers can read their minds.

Despite the system being, as Vice President Mike Pence said, “an Orwellian system premised on controlling virtually every facet of human life,” it appears the system may be accomplishing what it was designed to.

Since being launched, the system has caused 3.5 million people to “voluntarily fulfill their legal obligations,” such as paying overdue fines, according to the National Public Credit Information Center.

This includes 37 people who paid a total of 150 million yuan (US$22 million) in overdue fines. Whether it works or not, such a system has deeply concerning implications for the classist division of Chinese society with little room for errors or mistakes.

As a slogan often repeated in Chinese state media suggests, “Once you lose trust, you will face restrictions everywhere.”

This article was originally published by Futurism. Read the original article.

The post How China’s ‘Social Credit System’ Controls The Behavior Of Citizens appeared first on Science Afrique.

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Skin is our largest organ and something we may take for granted when it’s healthy. As an academic dermatologist I frequently hear misleading “facts” that seem to be stubbornly enduring. Here I have highlighted 7 common facts about our skin and some of the most commonly shared myths that can be cleared up immediately.

7 Common Facts About Our Skin 1. Skin constantly renews itself

TRUE The skin provides a dynamic barrier between your body’s internal environment and the outside world.

Cells called keratinocytes in the epidermis (the outer layer of skin) are constantly dividing to produce a supply of cells that move up through this layer and are shed from its surface.

Skin is a rich source of stem cells with the capacity to divide and renew themselves.

2. Drink two litres of water a day for healthy skin

FALSE The amount of water you drink does not directly affect your skin. Water is supplied to the skin by blood flowing through the dermis, the inner layer of skin; water is lost from the epidermis, especially in a dry environment.

Water is needed to maintain skin hydration and when you become seriously dehydrated your skin appears dull and is less elastic. In a healthy person the internal organs – kidneys, heart and blood vessels – control the amount of water reaching the skin.

There is no fixed volume of water that you need to drink, it simply depends on the amounts you are using and losing.

3.Stress can make skin unhealthy

TRUE There are many health issues in modern life that we blame on stress, but several skin conditions have been shown in scientific studies (see below), to be worsened by life events, possibly via stress hormones including cortisol (a steroid hormone made in the adrenal glands).

Notable examples are alopecia areata, an auto-immune condition where the body’s immunity begins to attack the hair follicles, causing hair to fall out; psoriasis, another auto-immune condition that causes skin thickening, scaling and inflammation; and eczema, itchy red skin inflammation often occurring alongside asthma, hay fever and other allergies.

Unfortunately a flare up of these skin conditions is exactly what you don’t need when you are feeling stressed or under pressure.

4. Eating chocolate causes acne

FALSE Acne vulgaris, the common “teenage” acne which can actually persist into your 30s and 40s, occurs as a result of the interaction between hormonal effects on grease glands in the skin, plus the skin’s immune response to blocked pores and microbes living on the skin.

Eating a high fat diet is unhealthy for many reasons, but it doesn’t cause acne.

In fact some tablets prescribed for severe acne such as oral isotretinoin are better absorbed when pills are swallowed with a fatty meal – and that could include chocolate.

5. Washing powder causes eczema

FALSE Eczema is a condition where the skin is dry, itchy and red. It is caused by a combination of genetic factors (how your skin is made) and environmental effects, leading to inflammation.

Soap, detergents and washing powders can irritate the skin and contribute to dryness because they remove oil from the skin (just as washing-up liquid removes grease from your dishes). 

Biological washing powders contain enzymes – proteins that break down fats and other proteins to remove stains – and these can irritate sensitive skin, so they may worsen eczema.

It is important that any washing power is thoroughly rinsed out of clothing before it is worn, to avoid skin irritation.

6. White marks on nails = calcium deficiency

FALSE Nails are manufactured in the nail matrix, an area under the skin at the top edge of your nail. If the matrix is traumatised, bumped or bitten, an irregularity in the developing nail occurs and air can become trapped.

This appears as a white mark as the nail grows out. Calcium is important for healthy nails (as well as bones and teeth) but these white marks are not a sign of deficiency.

7. Sunshine is good for you

TRUE & FALSE Many people have experienced the feel-good factor of a sunny day, but there are good and bad effects of sunlight.

Light from the sun includes a mixture of different wavelengths of light: some are visible to the human eye, some are shorter than the colours we can see – these are called ultraviolet (UV) – and some are longer, the infrared.

Different wavelengths have different effects on skin.

UVB is used by skin to manufacture vitamin D which is essential for bone health. Without sun exposure this vitamin must be obtained from the diet.

Dermatologists use specific wavelengths of UVA and UVB in carefully controlled doses to reduce skin inflammation, a valuable treatment for some skin conditions.

But when the skin is exposed to too much UV it can damage the skin cells’ DNA, leading to uncontrolled growth – the basis of cancer.

As a simple rule, unless you have a disease or treatment that suppresses your immune system, sunshine is good for you in moderation, but always avoid getting sunburned.

Keep it simple

The basic principles of keeping skin healthy are mainly common sense. You should wash your skin regularly to remove dirt, but not so much that you remove the essential moisture and water-proofing substances.

Use a moisturiser if your skin feels tight or dry – a greasy ointment works best unless you have acne-prone skin, in which case you should use a non-greasy water-based cream.

Avoid stress if possible, eat a healthy diet and drink water when you feel thirsty. And finally, protect your skin from too much sun with a hat and clothing or sunscreen.

Sara J Brown, Professor of Molecular & Genetic Dermatology, Wellcome Trust Senior Research Fellow, University of Dundee.

The 7 Common Facts About Our Skin Was Republished from The Conversation under a Creative Commons license. Read the original article.

The post 7 Common Facts About Our Skin That You Didn’t Know appeared first on Science Afrique.

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In the history of the HIV pandemic, only one patient had ever successfully shown the most common strain of the virus, HIV–1, could be put into remission. Until now.

After more than a decade – and with over half a trillion US dollars spent on HIV/AIDS research this century – we finally know that this incredible result can be replicated.

Science has now recorded a significant breakthrough as for the second time ever, a patient has experienced sustained remission from HIV–1 infection after being treated with stem cell transplants, scientists report in a new paper due to be published in Nature.

It may have been 12 years since the famous ‘Berlin patient’ made history by becoming the first person to sustain HIV–1 remission without receiving anti-retroviral (ARV) drugs, but the newly announced case of an anonymous male British patient demonstrates the first result was not unique.

“By achieving remission in a second patient using a similar approach, we have shown that the Berlin patient was not an anomaly, and that it really was the treatment approaches that eliminated HIV in these two people,” says virologist Ravindra Gupta from University College London.

The Berlin patient was actually an American (real name: Timothy Ray Brown) diagnosed with HIV while living in Germany. In 2007, he received a rare form of bone marrow transplant involving haematopoietic stem cells to treat his leukaemia.

Unexpectedly, the stem cell treatment – from a donor with a mutation of the CCR5 gene, which is a co-receptor for the HIV–1 infection – ended up with Brown’s HIV going into remission, where is has remained ever since.

For this reason, he’s often described as being the first patient ‘cured’ of HIV, although technically that’s incorrect, since remission and cures are not the same thing (as sometimes remissions are not complete, if the viral load stages a resurgence).

In the new case, now dubbed the ‘London patient’, the anonymous male also received a stem cell treatment from a donor with the same CCR5 gene mutation, this time while being treated for Hodgkin’s lymphoma.

Sixteen months after the procedure (which notably didn’t include radiotherapy, unlike the Berlin patient), the London patient discontinued ARV drugs (aka ART therapy), and has currently been in HIV remission for over 18 months.

That’s too soon to say he’s been fully cured, the scientists warn, but it’s nonetheless a hugely promising step that teaches us more about how the Berlin and London patients are keeping HIV at bay.

“This is a long time to be in remission off ART, so this is exciting,” infectious diseases expert Sharon Lewin from the University of Melbourne, who wasn’t involved with the study, explains.

“Coming 10 years after the successful report of the Berlin patient, this new case confirms that bone marrow transplantation from a CCR5-negative donor can eliminate residual virus and stop any traces of virus from rebounding.”

Doctors say they’ll need to keep monitoring the London patient to see how his condition develops from here, and point out that this treatment would not necessarily work with all patients – not to mention that the donated stem cells used in this case are very rare, owing to the specific CCR5 mutation involved.

Nonetheless, future research into how this HIV receptor functions could bring us a lot closer to an eventual cure for HIV, which currently infects around 37 million people worldwide.

“This second documented case does reinforce the message that HIV cures are possible,” says infection and immunity researcher Anthony Kelleher from UNSW in Australia, who wasn’t involved with the study.

“This tells us that the feasibility, and importantly, the availability of delivering this approach could possibly be achieved by the rapidly accelerating field of gene editing and related gene therapies. However, there are still significant hurdles in this field as well.”

The findings are reported in Nature (link not yet live at time of writing).

The post Breakthrough: Another HIV Patient Has Gone Into ‘Long-Term’ Remission appeared first on Science Afrique.

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Basal body temperature (BBT or BTP) is the lowest body temperature attained during rest (usually during sleep). It is usually estimated by a temperature measurement immediately after awakening and before any physical activity has been undertaken.
In women, ovulation causes a sustained increase of at least 0.2 °C (0.4 °F) in BBT. Monitoring BBTs is one way of estimating the day of ovulation. The tendency of a woman to have lower temperatures before ovulation, and higher temperatures afterwards, is known as a biphasic temperature pattern.

Basal Temperature should always be measured in the morning, immediately after awakening. It is forbidden to drink alcohol and have sex the day before the measurement. Also, if you drink medications or even regular food supplements, the result will be blurred.

The usual body temperature can also increase. Everyone knows that the temperature of 37 degrees provokes weakness and unwillingness to do anything, here is about the same. Do not try to bring down the temperature with aspirin, it will not bring a positive result. In this case, it is better to take off your warm clothes and put on something light, it is desirable to refresh and air a room, try to avoid physical exertion. Basal temperature is one of the early signs of pregnancy and it is believed that 18 consecutive days of elevated temperatures means a woman is almost certainly pregnant. Very often, this condition is also a consequence of nervous tension, so it alone is not enough to confirm pregnancy.

What Are The Proper Test To Determine Pregnancy 100%


The post How To Measure Basal Temperature Correctly appeared first on Science Afrique.

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For the second time, Senator Cory Booker announced a bill to make recreational marijuana use legal across the entire US.

The Marijuana Justice Act, which Booker and Representatives Barbara Lee and Ro Khanna announced on Thursday, would not only legalize marijuana but also retroactively erase marijuana possession charges from Americans’ criminal records, according to Rolling Stone — a monumental shift in U.S. drug policy.

Cory Booker, a 2020 Democratic hopeful, first introduced a similar bill in 2017 that didn’t make it out of the Senate. Still, Booker has made it clear that a major component of his presidential bid will center around ending the War on Drugs, which has led to the over-policing and incarceration of racial minorities for nonviolent crimes.

“The failed War on Drugs has really been a war on people — disproportionately criminalizing poor people, people of color & people with mental illness,” Booker tweeted Thursday morning.

“I’m reintroducing the [Marijuana Justice] Act to begin reversing our failed federal drug policies.”

So far, other Democratic candidates Elizabeth Warren, Bernie Sanders, and Kamala Harris have all co-sponsored Booker’s new bill, according to NPR. Meanwhile, Senator Ron Wyden introduced a similar bill earlier this month.

A major component of the Marijuana Justice Act is its retroactive effect on people who were previously charged for marijuana possession and either served time in prison or are still incarcerated.

The American Civil Liberties Union (ACLU) reports that black people are four times as likely to be arrested for marijuana possession than white people, despite similar rates of drug use.

When various states have legalized recreational marijuana, it largely benefited wealthy, white business owners who opened up distribution centers. Meanwhile, black people continued to be arrested at higher rates and the predominantly-black cohort currently in prison remained there, Vox reports.

If Booker’s bill makes it through the Senate this time, those people wouldn’t be left behind.

The new bill would allow people currently in prison for possession to appeal for re-sentencing. People who already served time would have their criminal records expunged, according to Rolling Stone.

“It’s not enough to simply decriminalize marijuana. We must also repair the damage caused by reinvesting in those communities that have been most harmed by the War on Drugs,” Booker said in a statement sent to Rolling Stone.

“And we must expunge the records of those who have served their time. The end we seek is not just legalization, it’s justice.”

This article was originally published by Futurism. Read the original article.

The post US Government Strongly Considering Legalising Marijuana Nation-Wide appeared first on Science Afrique.

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After several years of delays and setbacks, SpaceX and NASA are closing in on the first experimental launch of a commercial spaceship designed to fly astronauts into orbit.

The demonstration mission, called Demo-1, is scheduled to launch aboard a Falcon 9 rocket on Saturday at 2:49 am ET (7:49 am UTC) from Kennedy Space Center in Cape Canaveral, Florida.

The goal of the launch is to show that Crew Dragon, or Dragon V2 – a new spaceship that Elon Musk’s spaceflight company designed for NASA – is safe to fly astronauts to and from the International Space Station.

The experimental spaceship won’t have any people on board, but it will ferry a spacesuit-clad dummy and some cargo to the the US$150 billion orbiting laboratory. If this test proves successful, SpaceX may launch its first astronauts as soon as July.

“Demo-1 is a flight test, it absolutely is, although we view it also as a real mission, a very critical mission,” Kirk Shireman, who manages the space station program at NASA’s Johnson Space Center, said during a press briefing about the upcoming launch.

“The ISS still has three people on board, and so this vehicle coming up to the ISS for the first time has to work. It has to work.”

Demo-1 is part of a roughly US$8 billion effort by NASA called the Commercial Crew Program, which aims to restore NASA’s ability to launch astronauts on its own ships.

The agency has not had a way to do that since it retired the last space shuttle in July 2011. (US astronauts currently fly to and from the ISS on Russian Soyuz spacecraft.)

Saturday’s launch would mark the first launch of an American-made spaceship for astronauts since then.

“Additional launch readiness reviews today from NASA’s Commercial Crew Program, space station team, and SpaceX’s launch team concluded the teams are still ‘go’ for launch of the first uncrewed test flight of the Crew Dragon on a mission to the International Space Station,” Stephanie Martin, a NASA spokesperson, wrote in a blog post on Wednesday.

How to watch SpaceX’s Crew Dragon launch live online

NASA TV plans to broadcast live video and commentary of the Falcon 9 rocket launch starting at 2am ET on March 2. You can watch it using the embedded player below. SpaceX may also stream its own webcast of the launch.

NASA Live: Official Stream of NASA TV - YouTube

But first, the weather must cooperate. On Thursday morning, the US Air Force released a weather forecast suggesting there will be a roughly 20 percent chance of delay due to cloud cover that is too thick to launch a rocket within NASA’s margins of safety.

“Lingering moisture may lead to stubborn cloud cover sticking around for much of the day Friday,” the report said, noting that those clouds could lead SpaceX and NASA to delay the launch if they linger too long.

The backup launch date is Tuesday, March 2, though the forecast for Tuesday is markedly worse. The USAF weather report says there could be a 40 percent chance of delay then, due to 100 mph (160 km/h) winds in the upper atmosphere

This article was originally published by Business Insider.

The post Watch the First Ever SpaceX Commercial Spaceship Live Launch appeared first on Science Afrique.

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What do you think spiders eat? Insects? Yeah, that’s true. But their diets can actually be a lot more varied than that – and biologists have observed a spider smorgasbord that will blow your mind.

In the Amazon rainforest, a team of researchers recorded spiders and other arthropods such as centipedes feasting on tadpoles, lizards, frogs, and, on one very memorable occasion, a tarantula the size of a dinner plate killing a young opossum and dragging it off to devour at leisure.

Their discovery of arthropod predation was incidental; the researchers recorded several events because they involved frogs and lizards, eventually realising they had enough such encounters to compile a paper in its own right.

“Considering that there are hundreds of invertebrates that potentially prey upon vertebrates, the number of possible interactions between species is huge, and we are highlighting that fact in this paper,” said U-M biologist Rudolf von May.

The resulting paper includes encounters from 2008, 2012, 2016 and 2017. Most of them were recorded at night; most of the predators recorded were spiders; and most of the prey were amphibians.

But one occasion really stands out. The team heard some sounds in the leaf litter and went to check it out.

“We looked over and we saw a large tarantula on top of an opossum,” said U-M biologist Michael Grundler. “The opossum had already been grasped by the tarantula and was still struggling weakly at that point, but after about 30 seconds it stopped kicking.”

When the mammal stopped struggling, the tarantula dragged it away out of sight (you can see the encounter at 0:11 in the video below).

Amazon Spiders - YouTube

It’s not surprising that spiders have varied diets. We’ve seen spiders in South America and Australia chowing down on snakes, mice, and birds, and spiders that eat fish can be found round the globe.

It’s thought that these larger feasts are few and far between, supplementing a diet mostly of smaller, easier to catch insects. But it looks like the extent that spiders take down larger prey may have been underestimated, even though the majority of their diet does consist of bugs.

“This is an underappreciated source of mortality among vertebrates,” said evolutionary biologist Daniel Rabosky of the University of Michigan (U-M).

“A surprising amount of death of small vertebrates in the Amazon is likely due to arthropods such as big spiders and centipedes.”

For several years, the team has studied reptiles and amphibians in the Amazon rainforest at the foot of the Andes. In that region, there are around 85 amphibian species and 90 reptiles.

The tarantula, belonging to the genus Pamphobeteus, was about the size of a dinner plate (legs included); the mouse opossum, of the Marmosops genus, was a juvenile about the size of a softball. As you can see in the picture and video, its body is bigger than the tarantula’s.

The encounter is likely the first documentation of a large Mygalomorph spider preying on an opossum.

“We were pretty ecstatic and shocked, and we couldn’t really believe what we were seeing,” Grundler said. “We knew we were witnessing something pretty special, but we weren’t aware that it was the first observation until after the fact.”

But it’s not all blood and guts. The team observed the surprisingly friendly relationship one species of Pamphobeteus tarantula has with one – and just one – genus of frog, a relative of the dotted humming frog. The tarantula preys on every other frog, but leaves this little guy alone.

The relationship between several species of tarantula and the dotted humming frog has been well documented, and it’s possible that it’s of mutual benefit – the frog gets leftovers and protection from the spider, and in return eats the ants that prey on the spider’s eggs.

The team observed both dotted humming frogs and juvenile tarantulas leaving the same burrow for a night of foraging. Some of the tarantulas had fly larvae crawling on their bodies, which the team suggests might mean the frogs also help control parasites in the shared burrows.

Isn’t the idea of frogs and tarantulas being BFFs just the most adorable thing?

The research has been published in Amphibian and Reptile Conservation.

The post Watch as a Gigantic Tarantula Drags a Baby Opossum Away to Devour It appeared first on Science Afrique.

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Scientists are in the process of developing an incredible new nanotechnology which could one day gift us humans with the ability to see in the dark. The device has been tested on mice with amazing success, and there’s little to say it wouldn’t be equally effective on other mammals. The only obvious challenge is – how comfortable are you with needles to the eyeball?

Research led by the University of Science and Technology of China produced particles that adhere to light-detecting cells in the retina and help them respond to near-infrared (NIR) wavelengths.

The back of our eye, which is where the retina is, acts like a television screen in reverse. As the full spectrum of light falls on its cells, some wavelengths trigger chemical reactions we perceive as either colour or intensity.

Rod-shaped cells tell our brain how bright it is. They react strongly to light waves around 500 nanometres in size, but struggle to respond to anything above 640 nanometres, well into the red part of the spectrum.

We also have three types of tapering ‘cone’ shaped photoreceptor cells, each sensitive to their own parts of the spectrum. Combined, they provide our brains with the detail needed to tell colours apart.

But those cones also fail to detect light longer than around 700 nanometres, which means anything beyond the red part of the spectrum is completely invisible to us.

That’s a shame. What looks like darkness to us is often washed in low-energy, low wavelength parts of the spectrum. A number of animals, such as snakes and frogs, have evolved ways to tap into these wavelengths to track prey or see better at night.

Unfortunately mammals never managed to evolve what it takes to see even the edge of this infra-red spectrum. We humans have it relatively lucky. Mice only have rods and two types of cone cells, which all top out at wavelengths a little under ours.

There are quirks of chemistry that can help us glimpse a flash of NIR light, but generally speaking, an infra-red landscape is strictly off limits to us humans.

Bulky night vision goggles can capture this radiation and amplify it in wavelengths we can see, but wearing such tech is cumbersome and it can’t be used under daylight conditions.

The nanoparticles developed by the researchers in this latest innovation act like miniature night vision devices – only these ones sit directly on the actual light-sensitive cells.

Called retinal photoreceptor-binding upconversion nanoparticles, they’re a protein built to adhere to both rod and cone photoreceptors and transduce long wavelengths into shorter ones.

The result is a nanoscale device that acts like a tiny antenna, soaking up invisible NIR radiation and turning it into a colour that is more likely to trigger rods and cones into action, painting the world in hues of green.

Injected into mice, the whole process seems to work brilliantly. The nanoantennae were shown to not only stick to photoreceptors, but an LED shining weakly at 980 nanometres elicited retinal responses that were demonstrated to affect the brain’s visual cortex.

In a more practical experiment, the treated mice were able to differentiate simple shapes such as triangles and circles illuminated by the LED under various conditions. Best of all, they were still able to see just fine under normal daylight conditions.

The vision change didn’t come with awful side effects either. The only issue the team found was cloudiness in the eyes of the mice.

The mouse visual system is similar enough to humans that we might expect a version of this method could potentially work for us, too. In fact, there’s even a weird sort-of precedent.

A few years ago, biohackers rigged a similar process using a light sensitive substance called Chlorin e6 to make the retina generally more sensitive to light. Applied as eye drops, subjects could allegedly see longer distances under low light conditions.

Whether this promises genuine technology or was simply an overhyped experiment is up for debate. Eye drops would certainly be better than an injection into the eyeball, but this new nanotechnology has far more rigorous science to back it up.

It’s not hard to come up with cool uses for such tech. Military applications aside, who wouldn’t want to see better at night? Astronomers, for one.

“We may have the capability to view all the hidden information from NIR and IR radiation in the Universe which is invisible to our naked eyes,” says biochemist Gang Han from the University of Massachusetts Medical School.

But there are also serious research benefits in the form of experimental tools that can investigate visual processes on new levels.

“With this research, we’ve broadly expanded the applications of our nanoparticle technology both in the lab and translationally,” says Han.

“These nanoantennae will allow scientists to explore a number of intriguing questions, from how the brain interprets visual signals to helping treat colour blindness.”

This research was published in Cell.

The post Scientists Are Developing A New Nanotech Device That Could Give Humans Night Vision appeared first on Science Afrique.

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