Sweet tooth blocking hormone found in liver that curbs desire for sugar


Sweet tooth no more: A hormone found in liver could curb the desire for sugar

A way to block a “sweet tooth” may be in prospect after scientists identified a liver hormone that suppresses the desire for sugar.

Research on mice and monkeys showed that the hormone, FGF21, signals the brain to avoid seeking sweet foods.

Harnessing the effect, possibly by copying the the hormone’s action with a drug, could help patients who are obese or suffering from Type 2 diabetes, scientists believe.

Although certain hormones were already known to regulate appetite, this is the first one that is specific to sugar consumption.

Dr Matthew Gillum, one of the scientists from the University of Copenhagen in Denmark, said: “We never imagined that a circulating, liver-derived factor would exist whose function is to control sweet appetite.

“We are very excited about investigating this hormonal pathway further.”

The study, published in the journal Cell Metabolism, showed that FGF21 exerted a surprisingly powerful effect.

In monkeys, a single dose caused them to lose interest in sweetened water almost immediately.

Tests in mice revealed that the liver produced the hormone in response to sugar intake.

After entering the bloodstream, FGF21 suppressed sugar appetite by acting on the hypothalamus region of the brain.

The hormone was already known to enhance insulin sensitivity, making it easier for the body to keep blood sugar at a healthy level.

“Now there’s this dimension where FGF21 can help people who might not be able to sense when they’ve had enough sugar, which may contribute to diabetes,” said co-author Lucas BonDurant, a Phd student from the University of Iowa in the US.

The research showed that FGF21 did not reduce intake of all sugars – sucrose, fructose and glucose – equally, and did not affect consumption of complex carbohydrates.

One reason FGF21 exists in animals could be to improve diet quality, said the scientists.

Another possibility, since sugar can ferment, was that it helped the liver protect itself from excess alcohol.

The FGF21 pathway involves a molecule called carbohydrate responsive element-binding protein (ChREBP), a key regulator of glucose metabolism and fat storage.

‘Winter vomiting disease’ on the rise in California, officials say


This transmission electron micrograph, TEM, reveals some of the ultra structural morphology displayed by norovirus virions, or virus particles. Noroviruses belong to the genus Norovirus, and the family Caliciviridae. They are a group of related, single-s

This transmission electron micrograph, TEM, reveals some of the ultra structural morphology displayed by norovirus virions, or virus particles. Noroviruses belong to the genus Norovirus, and the family…It’s a disease humorist Stephen Colbert once poked fun at in this tweet: “Remember, if you’re in public and have the winter vomiting bug, be polite and vomit into your elbow.”

But officials at the California Department of Public Health say a sudden increase in norovirus infections is no laughing matter.

Already, the state has confirmed 32 outbreaks since Oct. 1 — far more than the nine cases reported last year at this time—and officials are warning Californians to wash their hands frequently to guard against infection.

Norovirus, also known as the winter vomiting disease, is a highly contagious virus that causes gastroenteritis, an illness that usually involves vomiting and diarrhea. It is the most common cause of gastroenteritis in the U.S. and is responsible for approximately 20 million illnesses each year, with between 570 and 800 deaths reported annually, health officials said.

The virus can spread quickly in closed and crowded environments, such as hospitals, nursing homes, daycare centers, schools, cruise ships and food service settings such as restaurants. Sickened people can still be contagious up to two weeks or more after recovery.

In the recent California outbreaks, the majority of cases have occurred at nursing homes and other long-term care facilities, with the remainder hitting schools and event centers, health officials said.

It can spread through direct contact with an infected person, consuming infected foods or liquids, or by touching a contaminated surface and then touching one’s mouth. Symptoms usually begin 12 to 48 hours after a person has been exposed and last for one to three days.

The virus causes your stomach or intestines or both to get inflamed, according to the U.S. Centers for Disease Control and Prevention. This leads the sufferer to have stomach pain, nausea, diarrhea and vomiting. These symptoms can be serious for some people, especially young children and older adults.

“One of the most important things you can do to avoid norovirus and other illnesses this holiday season is to wash your hands frequently with soap and running water for at least 20 seconds,” Karen Smith, CDPH director and state public health officer, said in a prepared statement. “This is especially important after using the bathroom, changing diapers, and before preparing or eating food.”

Hand sanitizers are not effective against norovirus, Smith added.

Although it is called the winter vomiting disease, it can strike during all seasons.

In May, several patrons and employees at The Sky Room—an upscale Long Beach restaurant—fell ill in a norovirus outbreak. The restaurant closed for four days in order to sanitize the restaurant and bar.

The disease struck again in August at a Ventura County Chipotle restaurant, where an outbreak was believed responsible for sickening more than 60 customers. Managers were forced to shut down the restaurant, throw out the remaining food and disinfect all surfaces.

More recently, a norovirus outbreak may have sickened as many at 50 students at Chapman University. The gastrointestinal illness was first reported Dec. 2 by several students and grew rapidly.

The Orange County Health Care Agency investigated the cause of the outbreak and one source could have been the school’s only cafeteria, the agency said. The cafeteria was closed and disinfected, the campus was swept down and the bathrooms and common areas were also cleaned.

“In addition to washing your hands after every bathroom visit, this includes washing fruits and vegetables before eating, cleaning and disinfecting food preparation equipment and surfaces, and thoroughly cooking all meats, fish and poultry,” health officials said of prevention measures.

Exceptionally strong and lightweight new metal created


UCLA researchers create exceptionally strong and lightweight new metal
At left, a deformed sample of pure metal; at right, the strong new metal made of magnesium with silicon carbide nanoparticles. Each central micropillar is about 4 micrometers across. Credit: UCLA Scifacturing Laboratory

A team led by researchers from the UCLA Henry Samueli School of Engineering and Applied Science has created a super-strong yet light structural metal with extremely high specific strength and modulus, or stiffness-to-weight ratio. The new metal is composed of magnesium infused with a dense and even dispersal of ceramic silicon carbide nanoparticles. It could be used to make lighter airplanes, spacecraft, and cars, helping to improve fuel efficiency, as well as in mobile electronics and biomedical devices.

To create the super-strong but lightweight metal, the team found a new way to disperse and stabilize nanoparticles in . They also developed a scalable manufacturing method that could pave the way for more high-performance lightweight metals. The research was published today in Nature.

“It’s been proposed that nanoparticles could really enhance the strength of metals without damaging their plasticity, especially light metals like magnesium, but no groups have been able to disperse ceramic nanoparticles in molten metals until now,” said Xiaochun Li, the principal investigator on the research and Raytheon Chair in Manufacturing Engineering at UCLA. “With an infusion of physics and materials processing, our method paves a new way to enhance the performance of many different kinds of metals by evenly infusing dense nanoparticles to enhance the performance of metals to meet energy and sustainability challenges in today’s society.”

Structural metals are load-bearing metals; they are used in buildings and vehicles. Magnesium, at just two-thirds the density of aluminum, is the lightest structural metal. Silicon carbide is an ultra-hard ceramic commonly used in industrial cutting blades. The researchers’ technique of infusing a large number of silicon carbide smaller than 100 nanometers into magnesium added significant strength, stiffness, plasticity and durability under high temperatures.

The researchers’ new silicon carbide-infused magnesium demonstrated record levels of specific strength—how much weight a material can withstand before breaking—and specific modulus—the material’s stiffness-to-weight ratio. It also showed superior stability at high temperatures.

Ceramic particles have long been considered as a potential way to make metals stronger. However, with microscale ceramic particles, the infusion process results in a loss of plasticity.

Nanoscale particles, by contrast, can enhance strength while maintaining or even improving metals’ plasticity. But nanoscale tend to clump together rather than dispersing evenly, due to the tendency of small particles to attract one other.

To counteract this issue, researchers dispersed the particles into a molten magnesium zinc alloy. The newly discovered nanoparticle dispersion relies on the kinetic energy in the particles’ movement. This stabilizes the particles’ dispersion and prevents clumping.

To further enhance the new metal’s strength, the researchers used a technique called high-pressure torsion to compress it.

“The results we obtained so far are just scratching the surface of the hidden treasure for a new class of metals with revolutionary properties and functionalities,” Li said.

The new metal (more accurately called a nanocomposite) is about 14 percent nanoparticles and 86 percent magnesium. The researchers noted that is an abundant resource and that scaling up its use would not cause environmental damage

Why This Newly Discovered Shark Is A Real Ninja


Several shark species have cool names, like great white, hammerhead, goblin andcookiecutter.

Now, we have one more to add to the list. Meet the newest type of lanternshark: the ninja lanternshark.

VICTORIA VÁSQUEZ
The species of lanternshark is the first of its kind ever found in Central American waters.

Researcher Victoria Vásquez and her colleagues discovered the previously unidentified shark after recovering its body from storage at the California Academy of Science.

It’s the first lanternshark that’s ever been found in Central American waters. Vásquez said they were able to identify it as a lanternshark based on several characteristics.

“It had photophores (light emitting organs),” she told The Huffington Post, “two dorsal fins with a spine on each one, and dignathic heterodonty (upper teeth and lower teeth are different).”

Vásquez said ninja lanternsharks live in the deep ocean. They have tiny dots that glow throughout their body, which, unlike most bioluminescent creatures, they use to camouflage themselves within the deep’s limited light and sneak up on their prey.

Remind you of anything?

NIKO GUIDO VIA GETTY IMAGES
Researcher Victoria Vásquez’s young cousins helped her come up with the inspiration for the name.

The researchers gave the newly identified shark the scientific name of Etmoterus benchleyi, in homage to the creator of the film “Jaws,” Peter Benchley.

But Vásquez wanted its common name to be extra special, so she enlisted for helpher younger cousins, who are between the ages of eight and 14.

They went over a few names, including Left Shark Lanternshark and Super Ninja Shark, until finally settling on a name her colleagues would find more reasonable: Ninja Lanternshark.

“The common name we have suggested refers to the shark’s color, which is a uniform sleek black as well as the fact that it has fewer photophores than other species of Lanternsharks,” Vásquez told HuffPost.

“We felt those unique characteristics would make this species stealthy like a ninja.”

VICTORIA VáSQUEZ
The scientists are now hunting for other “lost speciesof shark.

The body of the Ninja Lanternshark that the researchers examined was originally caught in 2010 in the waters of Central America. However, it was sent to the academy for temporary storage where it remained “unlooked at for five years,” Vásquez said.

She is currently helping her colleague, professor Dave Ebert, identify the “lost sharks” that have yet to be described.

“About 20 percent of all shark species have been discovered in just the last 10 years,” Ebert told Hakai Magazine. “My whole research is looking for ‘lost sharks.'”

Is String Theory Science?


A debate between physicists and philosophers could redefine the scientific method and our understanding of the universe

The idea that our Universe is part of a multiverse poses a challenge to philosophers of science.

Is string theory science? Physicists and cosmologists have been debating the question for the past decade. Now the community is looking to philosophy for help.

Earlier this month, some of the feuding physicists met with philosophers of science at an unusual workshop aimed at addressing the accusation that branches of theoretical physics have become detached from the realities of experimental science. At stake is the integrity of the scientific method, as well as the reputation of science among the general public, say the workshop’s organizers.

Held at the Ludwig Maximilian University of Munich in Germany on December 7-9, the workshop came about as a result of an article in Naturea year ago, in which cosmologist George Ellis, of the University of Cape Town in South Africa, and astronomer Joseph Silk, of Johns Hopkins University in Baltimore, Maryland, lamented a “worrying turn” in theoretical physics (G. Ellis and J. Silk Nature 516, 321–323; 2014).

“Faced with difficulties in applying fundamental theories to the observed Universe,” they wrote, some scientists argue that “if a theory is sufficiently elegant and explanatory, it need not be tested experimentally”.

First among the topics discussed was testability. For a scientific theory to be considered valid, scientists often require that there be an experiment that could, in principle, rule the theory out — or ‘falsify’ it, as the philosopher of science Karl Popper put it in the 1930s. In their article, Ellis and Silk pointed out that in certain areas, some theoretical physicists had strayed from this guiding principle — even arguing for it to be relaxed.

The duo cited string theory as the principal example. The theory replaces elementary particles with infinitesimally thin strings to reconcile the apparently incompatible theories that describe gravity and the quantum world. The strings are too tiny to detect using today’s technology — but some argue that string theory is worth pursuing whether or not experiments will ever be able to measure its effects, simply because it seems to be the ‘right’ solution to many quandaries.

Silk and Ellis also called out another theory that seems to have abandoned ‘Popperism’: the concept of a multiverse, in which the Big Bang spawned many universes — most of which would be radically different fromour own.

But in the opening talk at the workshop, David Gross, a theoretical physicist at the University of California, Santa Barbara, drew a distinction between the two theories. He classified string theory as testable “in principle” and thus perfectly scientific, because the strings are potentially detectable.

Much more troubling, he says, are concepts such as the multiverse because the other universes that it postulates probably cannot be observed from our own, even in principle. “Just to argue that [string theory] is not science because it’s not testable at the moment is absurd,” says Gross, who shared a Nobel prize in 2004 for his work on the strong nuclear force, which is well tested in experiments, and has also made important contributions to string theory.

Workshop attendee Carlo Rovelli, a theoretical physicist at Aix-Marseille University in France, agrees that just because string theory is not testable now does not mean that it is not worth theorists’ time. But the main target of Ellis and Silk’s piece were observations made by philosopher Richard Dawid of Ludwig Maximilian University in his book String Theory and the Scientific Method (Cambridge Univ. Press, 2013). Dawid wrote that string theorists had started to follow the principles of Bayesian statistics, which estimates the likelihood of a certain prediction being true on the basis of prior knowledge, and later revises that estimate as more knowledge is acquired. But, Dawid notes, physicists have begun to use purely theoretical factors, such as the internal consistency of a theory or the absence of credible alternatives, to update estimates, instead of basing those revisions on actual data.

Dynamic discussion
At the workshop, Gross, who has suggested that a lack of alternatives to string theory makes it more likely to be correct, sparred with Rovelli, who has worked for years on an alternative called loop quantum gravity. Rovelli flatly opposes the assumption that there are no viable alternatives. Ellis, meanwhile, rejects the idea that theoretical factors can improve odds. “My response to Bayesianism is: new evidence must be experimental evidence,” he says.

Others flagged up separate issues surrounding the use of Bayesian statistics to bolster string theory. Sabine Hossenfelder, a physicist at the Nordic Institute for Theoretical Physics in Stockholm, said that the theory’s popularity may have contributed to the impression that it is the only game in town. But string theory probably gained momentum for sociological reasons, she said: young researchers may have turned to it because the job prospects are better than in a lesser-known field, for example.

Historian of science Helge Kragh of Aarhus University in Denmark drew on historical perspective. “Suggestions that we need ‘new methods of science’ have been made before, but attempts to replace empirical testability with some other criteria have always failed,” he said. But at least the problem is confined to just a few areas of physics, he added. “String theory and multiverse cosmology are but a very small part of what most physicists do.”

That is cold comfort to Rovelli, who stressed the need for a clear distinction between scientific theories that are well established by experiments and those that are speculative. “It’s very bad when people stop you in the street and say, ‘Did you know that the world is made of strings and that there are parallel worlds?’.”

At the end of the workshop, the feuding physicsts did not seem any closer to agreement. Dawid — who co-organized the event with Silk, Ellis and others — says that he does not expect people to change their positions in a fundamental way. But he hopes that exposure to other lines of reasoning might “result in slight rapprochement”. Ellis suggests that a more immersive format, such as a two-week summer school, might be more successful at producing a consensus.

The science of Home Alone: would Kevin have killed the burglars?


A doctor weighs in on just how much damage a blow torch to the head would really do.

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When it comes to Christmas movies, it’s hard to beat Home Alone.

There’s Christmas songs, slapstick, Macaulay Culkin, and a heart-warming message about family at the end.

But have you ever wondered whether the two of burglars could actually have survived all of Kevin’s traps – some of which are pretty brutal? Back in 2012,Lauren Hansen over at The Week decided to get some answers, and interviewed Ryan St Clair, a medical doctor from Weill Cornell Medical College, to break down exactly what the impact of Kevin’s shenanigans would have been on the burglars’ health. And, basically, it’s not great.

We’ve summarised some of the medical effects of the worst injuries below, butcheck out Hansen’s full story at The Week to read the whole hilarious analysis (trust us, it’s worth it).

And we would hope that all our readers have seen Home Alone by now, but, just in case, we should probably emphasise the fact that there are spoilers ahead.

Injury: BB gun to the head at close-range

01-shot-in-face

You know, this is the scene when Marv puts his head through the doggy door and Kevin shoots him close-range in the forehead. It looks painful, but would it actually have done much damage? According to St Clair, it was survivable.

“Classic air-powered projectile weapons typically have muzzle velocities of 350 feet [107 metres] per second or less. A BB fired at close range from such a weapon could break the skin, but will not penetrate the skull, and is unlikely to penetrate Harry’s scrotum, especially through fabric,” St Clair told Hansen.

Injury: Grabbing the hot doorknob

6 ScaldHandDoor

In this scene, Harry tries to get in the front door – only to grab a doorknob that’s burning bright red. Sure, he screams about it, but St Clair explains to Hansen that the impact of this injury would actually be far worse.

“If this doorknob is glowing visibly red in the dark, it has been heated to about 751 degrees Fahrenheit [399 degrees Celsius]. By comparison, one second of contact with 155 degree [68 degrees Celsius] water is enough to cause third degree burns.

“The temperature of that doorknob is not quite hot enough to cause Harry’s hand to burst into flames, but it is not that far off… Assuming Harry doesn’t lose the hand completely, he will almost certainly have other serious complications, including a high risk for infection and ‘contracture’, in which resulting scar tissue seriously limits the flexibility and movement of the hand, rendering it less than 100 percent useful. Kevin has moved from ‘defending his house’ into sheer malice, in my opinion.”

Injury: Blowtorch to the head

8 firetorchHead 1

Speaking of burns, poor Harry gets scorched again when Kevin’s booby trap blow torch burns his scalp. And, again, he gets off unscientifically easy.

“Harry has an interesting reaction to having a lit blowtorch aimed directly at his scalp. Rather than remove himself from danger, he keeps the top of his skull directly in the line of fire for about seven seconds. What was likely a simple second-degree skin burn is now a full thickness burn likely to cause necrosis of the calavarium (skull bone). That means the skin and bone tissue on Harry’s skull will be so damaged and rotted that his skull bone is essentially dying and will likely require a transplant,” St Clair tells Hansen.

Injury: Paint can to the face

HomeAloneFinally, to top things off, Kevin smacks both Marv and Harry (who by now should be in a burns unit… or dead) with a swinging paint can on a string in the face. And they still keep going.

St Clair’s verdict?

“Assuming the paint can is full (roughly 10 pounds [4.5 kg]) and the rope is 10 feet [3 metres] long, Marv and Harry each take a roughly 2 kg-newton hit to the face. That is easily enough to fracture multiple facial bones, and is probably going to knock you out cold. Also, I wouldn’t expect either of the Wet Bandits to walk away from this with all of their teeth.”

So it turns out Kevin would probably have woken up on Christmas day a murderer if Home Alone was real life (although, to be fair, it was in self defence). But thankfully, it’s not, and we love the film anyway.

Go and read Hansen’s full (and hilarious) interview with St Clair over at The Week, and find out how much walking on sharp Christmas ornaments would really hurt, and whether an iron to the face would kill you.

And if you want some more debunking, find out whether that certain Game of Thrones character could have really crushed a man’s skull with his bare hands, and exactly how Viserys would have died from having molten gold poured on his head. Oh and while you’re at it, why not find out the science on whetherzombies could really exist.

FIDO vest lets service dog talk to humans


A researcher from Georgia Tech is working on giving dogs the ability to talk to humans, and it could have huge potential for service dogs.

dog

Melody Moore Jackson, creator and director of Georgia Tech’sBrainLab, is creating computerized vests for dogs so they can “speak.”

The vests come with a lever that the dog could tug, as well as a sensor that the dog can touch with its nose, Jackson demonstrated on Daily Planet’s Future Planet. When the dog activates the vest, either by pulling the lever or touching the sensor, it activates a controller unit attached to the vest.

The controller unit can then deliver an audio message or send a text via Bluetooth to a designated contact.

This could have huge potential for service dogs who often need to communicate to get help. If the dog’s owner is unconscious, the dog could more easily get help from a passerby using the vest. When the vest is activated, it can send a message like “excuse me my owner needs your attention,” Jackson demoed during an NPR interview.

Search and rescue dogs could also use the vests to send their GPS coordinates when they find someone.

But there are other ways the vest could communicate. For example, sometimes the dog may not want to communicate with a third-party person, but with their owner.

Jackson described a scenario in the NPR interview where a dog halted his blind owner because they were approaching wet concrete. When the owner used his cane to detect whether an object was in the way, he felt nothing and insisted that him and the dog keep walking.

The vest could’ve helped the dog more easily communicate that they had to change their route.

Jackson dubbed her efforts the FIDO Project, which stands for Facilitating Interactions for Dogs with Occupations. More research is being done to see if there are other areas on the vest that can be equipped with sensors — it’s important that the dog can easily reach any new areas that are used.

In a 2014 formal study, Jackson tested eight dogs who were wearing vests with five different sensors. The longest it took a dog to learn the system was 30 minutes — the fastest was 27 seconds.

That means it’s only a matter of time before communicating with your canine friend is taken to a new level.

Here’s why virgin birth is scientifically possible.


Christmas seems an appropriate time to ask whether it’s biologically possible to have a virgin birth. And you may be surprised to hear that it is possible – just not for humans, or any other mammals. Experiments with mice and other mammals show an egg must be fertilised with a sperm to kick off development of any kind. Just stimulating a mammal egg with chemicals or electricity doesn’t trigger it to divide normally.

It seems you need particular proteins from sperm to set up waves of calcium ions in the egg, which trigger further changes leading up to copying all the DNA and chromosomes, and dividing into two cells.

But you need more than just a protein trigger supplied by the sperm. You also need two copies of each chromosome in the fertilised egg. Normally one set is provided by the mother (in the egg nucleus) and one by the father (in the sperm nucleus).

You can engineer a mouse egg to have both nuclei from the same sex, but thisdoesn’t work. An egg with two maternal nuclei goes some of the way to making an embryo, but it shrivels up because there is little development of placenta. If both nuclei come from a male there is the opposite problem: a lot of placenta but hardly any embryonic development.

But why not?

It turns out that there are more than 30 imprinted genes that are active only if they come from a father through sperm. There are another 30 plus that are active only if they come from the mother. So genomic imprinting prevents virgin birth in all mammals, including humans.

Genomic imprinting is the different activity of genes according to which parent they come from. It was discovered in the 1990s, with its mechanism only sorted out in the last decade. It seems that the inactive gene is not mutated, but issilenced by attaching chemical groups to the DNA. These chemical groups are put onto genes in the testis or the ovary, and are removed during growth of the embryo.

Evidence that this silencing messes up uniparental embryos comes from engineering mice in which the imprinting process on one key gene is disrupted, leading to viable embryos with two mothers.

But it’s still a mystery as to why imprinting evolved. Was it selected for because it prevented virgin birth? Or was it the result of a war between the mother’s and father’s genes? This ‘sexual antagonism’ is suggested by the functions of many of the imprinted genes.

Generally, active genes from the father directly or indirectly promote growth, whereas active genes from the mother suppress growth. It has been suggested that the father’s genetic interests are best served by producing the biggest, toughest baby, whatever the cost to the mother (you can always find another female to mate with). The mother’s genetic interests are best served by limiting the claims on her health and energy so she can survive to bear more children.

Virgin birth in other animals

But virgin birth is possible, if you’re a reptile or a fish. For instance, pythons and Komodo dragon females that were long isolated were found to produce young that had only genes from the mother. It now seems to be an option in some snake species, and is known in several species of shark. Handy when there are no males around!

In fact, there are several lizards that are exclusively female. Some whiptail and gecko species in the arid southwest of the USA and the hot and dry interior of Australia have females whose unfertilised eggs develop fully – all into daughters.

The process is called parthenogenesis (literally ‘virgin creation’). The animals that practise it (snakes, sharks and lizards) don’t have to worry about genomic imprinting, which does not occur in egg-laying animals.

There are several ways reptiles can accomplish this. A female can make fertile eggs with the right number of chromosomes either by fusing an egg cell with another cell with one set of chromosomes. Alternatively the egg progenitor can undergo a variant form of division that leaves two copies of the genome.

This isn’t exactly cloning, because the mother’s gene copies are scrambled, but it does mean that all the genes of the offspring come from the mother.

Why sex?

The occurrence of parthenogenesis in reptiles poses a puzzle: what is the point of sex anyway? Wouldn’t your genes do better in the evolutionary race if your offspring received genes only from you? This ‘twofold cost of sex’ has been a serious question in the field for 80 years.

The answer seems to be that although parthenogenesis works fine in the short term, it will always lose out in the long run because recombining two genes each generation is a great way of scrambling the combinations of proteins that pathogens see.

A pathogen that can infect one individual can also infect others with the same genes, so it’s no point in having many cloned copies. For instance, the female-only Australian gecko is very susceptible to mite infestation.

So the answer to the question of whether virgin birth is a real possibility is: yes, unless you are a mammal.

What Is Antimatter And Why Are We Searching For It?


Scientists have been looking for antimatter since the early 1920’s. Is antimatter real?

http://www.sciencechannel.com/tv-shows/science-channel-presents/news/dnews-videos/what-is-antimatter-and-why-are-we-searching-for-it/

Anti ‘sweet tooth’ hormone discovered by scientists


A hormone which switches off the preference for sugary foods has been found by scientists

A little girl reaches for sweets
A hormone which regulates the urge for sugary food has been discovered by scientists

A cure for sugar cravings is a major step nearer after scientists identified a hormone which suppresses a “sweet tooth”.

Researchers say their findings, published online in the journal Cell Metabolism, could improve the diet and help patients who are diabetic or obese.

While sugar cravings are common, particularly at this time of year, the physiological mechanisms that trigger our “sweet tooth” were not well defined until now.

“FGF21 can help people who might not be able to sense when they’ve had enough sugar, which may contribute to diabetes”
Lucas BonDurant, University of Iowa

But the new study in mice shows that a hormone produced by the liver, fibroblast growth factor 21 (FGF21), suppresses the consumption of simple sugars.

The researchers say that FGF21 is produced in the liver in response to high carbohydrate levels. The hormone then enters the bloodstream, where it sends a signal to the brain to suppress the preference for sweets.

The study’s co-senior author Doctor Matthew Potthoff, assistant professor of pharmacology in the University of Iowa in the US, said: “This is the first liver-derived hormone we know that regulates sugar intake specifically.”

Previous research explains how certain hormones affect appetite; however, these hormones don’t regulate any specific macronutrient – carbohydrate, protein, fat – and are produced by organs other than the liver.

Co-first author Lucas BonDurant, a doctoral student, said: “We’ve known for a while that FGF21 can enhance insulin sensitivity.

A police union spokesman said it was demeaning for police to give out sweets

“Now, there’s this dimension where FGF21 can help people who might not be able to sense when they’ve had enough sugar, which may contribute to diabetes.”

The work is based on human genome-wide studies where researchers found associations between certain DNA mutations and people’s intake of specific macronutrients.

Two of the mutations were located near the FGF21 gene, prompting the researchers to identify the role of this hormone in regulating macronutrient preference.

They used genetically-engineered mouse models and pharmacological approaches to examine the role of FGF21 in regulating sugar cravings.

In normal mice, they injected FGF21 and gave the mice a choice between a normal diet and a sugar-enriched diet. They observed that the mice didn’t completely stop eating sugar, but they ate seven times less than normal.

The researchers also studied genetically-modified mice that either didn’t produce FGF21 at all or produced a lot of FGF21 – over 500 times more than normal mice.

The genetically-modified mice had a choice between the same two diets as the normal mice.

The researchers observed that the mice that didn’t produce FGF21 at all ate more sugar, whereas the mice that produced a lot of FGF21 ate less sugar.

Based on the results, they concluded that FGF21 decreases appetite and intake of sugar.

However, FGF21 does not reduce intake of all sugars – sucrose, fructose, and glucose – equally. FGF21 also doesn’t impact the intake of complex carbohydrates.

While the researchers found that FGF21 sends signals to the brain, they say additional work is necessary to identify the precise neural pathways that regulate FGF21’s ability to manage macronutrient preference.

The research team are focused on the hypothalamus – a section of the brain responsible for regulating eating behaviour and energy homeostasis.

Dr Potthoff added: “In addition to identifying these neural pathways, we would like to see if additional hormones exist to regulate appetite for specific macronutrients like fat and protein, comparable to the effects of FGF21 on carbohydrate intake.

“If so, how do those signals intertwine to regulate the neural sensing of different macronutrients?

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