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The smart mouse with the partially human brain

The smart mouse with the partially human brain | Amazing Science |

Mice have been created whose brains are half human. As a result, the animals are smarter than their siblings. The idea is not to mimic fiction, but to advance our understanding of human brain diseases by studying them in whole mouse brains rather than in dishes. The altered mice still have mouse neurons – the "thinking" cells that make up around half of all their brain cells. But practically all the glial cells in their brains, the ones that support the neurons, are human.

"It's still a mouse brain, not a human brain," says Steve Goldman of the University of Rochester Medical Center in New York. "But all the non-neuronal cells are human." Goldman's team extracted immature glial cells from donated human fetuses. They injected them into mouse pups where they developed into astrocytes, a star-shaped type of glial cell.

Within a year, the mouse glial cells had been completely usurped by the human interlopers. The 300,000 human cells each mouse received multiplied until they numbered 12 million, displacing the native cells.

"We could see the human cells taking over the whole space," says Goldman. "It seemed like the mouse counterparts were fleeing to the margins."

Human astrocytes are 10 to 20 times the size of mouse astrocytes and carry 100 times as many tendrils. This means they can coordinate all the neural signals in an area far more adeptly than mouse astrocytes can. "It's like ramping up the power of your computer," says Goldman.

A battery of standard tests for mouse memory and cognition showed that the mice with human astrocytes are much smarter than their mousy peers. In one test that measures ability to remember a sound associated with a mild electric shock, for example, the humanized mice froze for four times as long as other mice when they heard the sound, suggesting their memory was about four times better. "These were whopping effects," says Goldman. "We can say they were statistically and significantly smarter than control mice."

Goldman first reported last year that mice with human glial cells are smarter. But the human cells his team injected then were mature so they simply integrated into the mouse brain tissue and stayed put. This time, he injected the precursors of these cells, glial progenitor cells, which were able to divide and multiply. That, he says, explains how they were able to take over the mouse brains so completely, stopping only when they reached the physical limits of the space.

To explore further how the human astrocytes affect intelligence, memory and learning, Goldman is already grafting the cells into rats, which are more intelligent than mice. "We've done the first grafts, and are mapping distributions of the cells," he says.

Although this may sound like the work of science fiction – think Deep Blue Sea, where researchers searching for an Alzheimer's cure accidently create super-smart sharks, or Algernon, the lab mouse who has surgery to enhance his intelligence, or even the pigoons, Margaret Atwood's pigs with human stem cells – and human thoughts – Goldman is quick to dismiss any idea that the added cells somehow make the mice more human.

"This does not provide the animals with additional capabilities that could in any way be ascribed or perceived as specifically human," he says. "Rather, the human cells are simply improving the efficiency of the mouse's own neural networks. It's still a mouse."

However, the team decided not to try putting human cells into monkeys. "We briefly considered it but decided not to because of all the potential ethical issues," Goldman says. "It could be difficult to decide which animals to put human brain cells into. If you make animals more human-like, where do you stop?" he says.

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Centipede Genome Yields Surprises: Loss of Light Receptor Genes and Circadian Clock

Centipede Genome Yields Surprises: Loss of Light Receptor Genes and Circadian Clock | Amazing Science |

A team of scientists has sequenced the genome of the centipede for the first time and found that it has around 15,000 genes -- about 7,000 fewer than humans do.

Arthropods -- the most species-rich group of animals on Earth -- are divided into four classes, including insects, crustaceans, chelicerates and myriapods. The latter group, which includes centipedes, is the only class for which no genome had yet been sequenced, scientists said in a study, published in the journal PLOS Biology.

“With genomes in hand from each of the four classes of living arthropod, we can now begin to build a picture of the genetic make-up of their common ancestor,” Frank Jiggins, of the University of Cambridge's genetics department, and one of the researchers involved in the study, said in a statement. “For example, by comparing flies and mosquitoes with centipedes, we have shown that the innate immune systems of insects are much older than previously appreciated.”

As part of the study, the scientists sequenced the genome of “Strigamia maritima,” a northern European centipede. They found that its genome is more conserved than that of many other arthropods, such as the fruit fly, suggesting that the centipede has evolved more slowly from their common ancestor. Despite their name, centipedes do not have hundred legs. Strigamia maritima, which lives in coastal habitats, can have between 45 and 51 pairs of legs, but the number of pairs is always odd.

The researchers also discovered that the centipedes have lost the genes encoding all of the known light receptors used by animals, as well as the genes controlling the circadian rhythm, or the body clock.

“Strigamia live underground and have no eyes, so it is not surprising that many of the genes for light receptors are missing, but they behave as if they are hiding from the light. They must have some alternative way of detecting when they are exposed,” Michael Akam of the University of Cambridge and one of the lead researchers of the study, said in the statement.

Bernadette Cassel's curator insight, January 1, 6:47 PM


→  Le premier génome de myriapode séquencé   

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Brain-dwelling tapeworm in man's head sequenced

Brain-dwelling tapeworm in man's head sequenced | Amazing Science |

For the first time, the genome of a rarely seen tapeworm has been sequenced. The genetic information of this invasive parasite, which lived for four years in a UK resident's brain, offers new opportunities to diagnose and treat this invasive parasite.

The tapeworm, Spirometra erinaceieuropaei, has been reported only 300 times worldwide since 1953 and has never been seen before in the UK. The worm causes sparganosis: inflammation of the body's tissues in response to the parasite. When this occurs in the brain, it can cause seizures, memory loss and headaches. The worm's rarity means that little is known about its complex lifecycle and biology, however it is thought that people may be infected by accidentally consuming tiny infected crustaceans from lakes, eating raw meat from reptiles and amphibians, or by using a raw frog poultice - a Chinese remedy to calm sore eyes.

Before the 1cm-long parasite was diagnosed and successfully removed by surgery, it had travelled 5cm from the right side of the brain to the left. The tapeworm was placed on a histology slide by the hospital to confirm the clinical diagnosis. The patient is now systemically well.

"The clinical histology slide offered us a great opportunity to generate the first genome sequence of this elusive class of tapeworms," says Dr Hayley Bennett, first author of the study from the Wellcome Trust Sanger Institute. "However, we only had a minute amount of DNA available to work with - just 40 billionths of a gram. So we had to make difficult decisions as to what we wanted to find out from the DNA we had."

To identify the exact species of worm, the researchers sequenced one particular gene, the so-called 'barcode of life'. Fortunately for the patient, the gene's DNA sequence revealed that the parasite was the more benign of the two sparganosis-causing worm species. Remarkably, the team also were able to generate sufficient DNA sequence data using standard next-generation sequencing techniques to piece together a draft genome. This is now being used to investigate known and potential treatment targets, which may help patients in the future.

"We did not expect to see an infection of this kind in the UK, but global travel means that unfamiliar parasites do sometimes appear," says Dr Effrossyni Gkrania-Klotsas, study author from the Department of Infectious Disease, Addenbrooke's NHS Trust. "We can now diagnose sparganosis using MRI scans, but this does not give us the information we need to identify the exact tapeworm species and its vulnerabilities. Our work shows that, even with only tiny amounts of DNA from clinical samples, we can find out all we need to identify and characterize the parasite.

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These Engineered Parhyales Teach Us About How Evolution Works -- And Where It Fails

These Engineered Parhyales Teach Us About How Evolution Works -- And Where It Fails | Amazing Science |

A leg growing out of your mouth. Extra legs pushing out of your side. Walking parts where your swimming bits should be. If you’re a tiny crustacean in Nipam Patel’s lab, chances are good you’re not quite right—and that’s just the way these UC Berkley geneticists like it. By inducing birth defects in arthropods called parhyale, Patel’s team makes “monsters” that deliver a one-two punch, offering insights into the mechanics of evolution, and into ways we could treat (or even prevent) human birth defects and disease in the future.

The questions that drive Patel’s lab are deceptively simple, and brain-crushingly profound: How did Earth’s organisms become different from one another? How is an embryo “programmed” to know what it should look like? How might changes to that programming have advanced evolution itself? This frustrated, flailing parhyale—which, thanks to Patel’s crew, was born with almost perfect walking appendages where its swimming appendages should be—is helping to revolutionize how we think about all of it.

Welcome to the world of Hox genes, a roughly 600-million-year-old “toolkit” that controls how body plans—the head-to-tail layout of our symmetrical, physical selves—develop. Once thought to exist only in flies, Hox genes rocked biology in the mid-’80s when it was discovered that they were in every single animal on Earth. And while the number of Hox genes tends to vary according to how complex you are (insects have 8; humans have 39), the genes themselves have changed so little in millions of years that they’re what’s called "highly conserved" across species.

In labs, that means flies function surprisingly well when one of their Hox genes is swapped for the corresponding chicken Hox gene. From an evolutionary perspective, it means earthworms, humpback whales, butterflies, and humans are all just variations on a theme. “Despite the fact that we don’t think of ourselves as looking anything like a fly,” says Patel, “our development basically uses the same genes.”

Hox genes are “master instructors”—each oversees development in a different region of the body (head, thorax, abdomen), turning other genes on and off to ensure you grow the right form for your species. “In the field in general,” says Patel, “I think we’ve increasingly convinced people that single genes can have big roles in evolution,” but his team hunts proof, examples of how small tweaks to the Hox toolkit may have given rise to Earth’s massive species diversity.

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Single-cell phytoplankton in the ocean are responsible for roughly half of global oxygen production

Single-cell phytoplankton in the ocean are responsible for roughly half of global oxygen production | Amazing Science |

In a paper published in PNAS on Monday November 24, scientists laid out a robust new framework based on in situ observations that will allow scientists to describe and understand how phytoplankton assimilate limited concentrations of phosphorus, a key nutrient, in the ocean in ways that better reflect what is actually occurring in the marine environment. This is an important advance because nutrient uptake is a central property of ocean biogeochemistry, and in many regions controls carbon dioxide fixation, which ultimately can play a role in mitigating climate change.

"Until now, our understanding of how phytoplankton assimilate nutrients in an extremely nutrient-limited environment was based on lab cultures that poorly represented what happens in natural populations," explained Michael Lomas of Bigelow Laboratory for Ocean Sciences, who co-led the study with Adam Martiny of University of California - Irvine, and Simon Levin and Juan Bonachela of Princeton University. "Now we can quantify how phytoplankton are taking up nutrients in the real world, which provides much more meaningful data that will ultimately improve our understanding of their role in global ocean function and climate regulation."

To address the knowledge gap about the globally-relevant ecosystem process of nutrient uptake, researchers worked to identify how different levels of microbial biodiversity influenced in situ phosphorus uptake in the Western Subtropical North Atlantic Ocean. Specifically, they focused on how different phytoplankton taxa assimilated phosphorus in the same region, and how phosphorus uptake by those individual taxa varied across regions with different phosphorus concentrations. They found that phytoplankton were much more efficient at assimilating vanishingly low phosphorus concentrations than would have been predicted from culture research. Moreover, individual phytoplankton continually optimized their ability to assimilate phosphorus as environmental phosphorus concentrations increased. This finding runs counter to the commonly held, and widely used, view that their ability to assimilate phosphorus saturates as concentrations increase.

"Prior climate models didn't take into account how natural phytoplankton populations vary in their ability to take up key nutrients, "said Martiny. "We were able to fill in this gap through fieldwork and advanced analytical techniques. The outcome is the first comprehensive in situ quantification of nutrient uptake capabilities among dominant phytoplankton groups in the North Atlantic Ocean that takes into account microbial biodiversity."

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Life’s extremists may be an untapped source of antibacterial drugs

Life’s extremists may be an untapped source of antibacterial drugs | Amazing Science |

One of the most mysterious forms of life may turn out to be a rich and untapped source of antibacterial drugs. The mysterious life form is Archaea, a family of single-celled organisms that thrive in environments like boiling hydrothermal pools and smoking deep sea vents which are too extreme for most other species to survive.

“It is the first discovery of a functional antibacterial gene in Archaea,” said Seth Bordenstein, the associate professor of biological sciences at Vanderbilt University who directed the study, “You can’t overstate the significance of the antibiotic resistance problem that humanity is facing. This discovery should help energize the pursuit for new antibiotics in this underexplored group of life.”

Until the late 1970s, biologists thought that Archaea were just weird bacteria, but then a landmark analysis of their DNA showed that they represent an independent branch on the tree of life that stretches back more than three billion years. The realization that Archaea could be a source of novel pharmaceuticals emerges from a study of widespread horizontal gene transfer between different species conducted by a team of scientists from Vanderbilt University and Portland State University in Oregon.

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How hummingbirds achieve their aerobatic feats

How hummingbirds achieve their aerobatic feats | Amazing Science |
The most detailed aerodynamic simulation of hummingbird flight conducted to date demonstrates that it achieves its aerobatic abilities through a unique set of aerodynamic forces.

The sight of a tiny hummingbird hovering in front of a flower and then darting to another with lightning speed amazes and delights. But it also leaves watchers with a persistent question: How do they do it?

Now, the most detailed, three-dimensional aerodynamic simulation of hummingbird flight conducted to date has definitively demonstrated that the hummingbird achieves its nimble aerobatic abilities through a unique set of aerodynamic forces that are more closely aligned to those found in flying insects than to other birds.

The new supercomputer simulation was produced by a pair of mechanical engineers at Vanderbilt University who teamed up with a biologist at the University of North Carolina at Chapel Hill. It is described in the article “Three-dimensional flow and lift characteristics of a hovering ruby-throated hummingbird” published this fall in the Journal of the Royal Society Interface.

For some time researchers have been aware of the similarities between hummingbird and insect flight, but some experts have supported an alternate model which proposed that hummingbird’s wings have aerodynamic properties similar to helicopter blades. However, the new realistic simulation demonstrates that the tiny birds make use of unsteady airflow mechanisms, generating invisible vortices of air that produce the lift they need to hover and flit from flower to flower.

You might think that if the hummingbird simply beats its wings fast enough and hard enough it can push enough air downward to keep its small body afloat. But, according to the simulation, lift production is much trickier than that. For example, as the bird pulls its wings forward and down, tiny vortices form over the leading and trailing edges and then merge into a single large vortex, forming a low-pressure area that provides lift. In addition, the tiny birds further enhance the amount of lift they produce by pitching up their wings (rotate them along the long axis) as they flap.

Hummingbirds perform another neat aerodynamic trick – one that sets them apart from their larger feathered relatives. They not only generate positive lift on the downstroke, but they also generate lift on the upstroke by inverting their wings. As the leading edge begins moving backwards, the wing beneath it rotates around so the top of the wing becomes the bottom and bottom becomes the top. This allows the wing to form a leading edge vortex as it moves backward generating positive lift.

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Amazon frogs found to build mental maps of their surroundings with several hundred meters diameter

Amazon frogs found to build mental maps of their surroundings with several hundred meters diameter | Amazing Science |

Frogs, as we all know, lay eggs which eventually grow to become tadpoles. And tadpoles, because they have no legs, need water to survive. But the brilliant-thighed poison frog doesn't live in water, instead, it lives among leaf litter on the floor of the Amazonian rainforest. To keep their tadpoles alive, the adults carry them from puddle to puddle on their backs. Thus, the frogs need to know the location of all the puddles in their little part of world. Somehow, it seems, they build mental maps that allow them to move from one water nursery to the next without deviating.

To better understand the frogs, the researchers fitted several of them with tiny transmitters that allowed for tracking every move the volunteer frogs made. Then, they placed the frogs in different parts of the forest to see how well they did in finding their way back to where they lived. Remarkably, the researchers found that if the frogs were placed within a certain familiar range they were able to march straight back to their home without having to even pause or look around. Frogs that were placed in unfamiliar terrain on the other hand, became lost for awhile and had to work to get home. The researchers found that the range for familiar territory ranged at least up to 100 meters from where the frogs called home, though prior research has shown that such frogs typically roam in a circular area roughly 600 meters in diameter.

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Body's bacteria may keep our brains healthy and the blood-brain barrier intact

Body's bacteria may keep our brains healthy and the blood-brain barrier intact | Amazing Science |

The microbes that live in your body outnumber your cells 10 to one. Recent studies suggest these tiny organisms help us digest food and maintain our immune system. Now, researchers have discovered yet another way microbes keep us healthy: They are needed for closing the blood-brain barrier, a molecular fence that shuts out pathogens and molecules that could harm the brain.

The findings suggest that a woman's diet or exposure to antibiotics during pregnancy may influence the development of this barrier. The work could also lead to a better understanding of multiple sclerosis, in which a leaky blood-brain barrier may set the stage for a decline in brain function.

The first evidence that bacteria may help fortify the body’s biological barriers came in 2001. Researchers discovered that microbes in the gut activate genes that code for gap junction proteins, which are critical to building the gut wall. Without these proteins, gut pathogens can enter the bloodstream and cause disease.

In the new study, intestinal biologist Sven Pettersson and his postdoc Viorica Braniste of the Karolinska Institute in Stockholm decided to look at the blood-brain barrier, which also has gap junction proteins. They tested how leaky the blood-brain barrier was in developing and adult mice. Some of the rodents were brought up in a sterile environment and thus were germ-free, with no detectable microbes in their bodies. Braniste then injected antibodies—which are too big to get through the blood-brain barrier—into embryos developing within either germ-free moms or moms with the typical microbes, or microbiota.

The studies showed that the blood-brain barrier typically forms a tight seal a little more than 17 days into development. Antibodies infiltrated the brains of all the embryos younger than 17 days, but they continued to enter the brains of embryos of germ-free mothers well beyond day 17, the team reports online today in Science Translational Medicine. Embryos from germ-free mothers also had fewer intact gap junction proteins, and gap junction protein genes in their brains were less active, which may explain the persistent leakiness.

Vloasis's curator insight, November 22, 2014 11:04 AM

So basically, embryos from germ-free mothers did not develop as efficiently, or as well?

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Devastating Starfish Disease Seems To Be Caused by Waterborne Densovirus

Devastating Starfish Disease Seems To Be Caused by Waterborne Densovirus | Amazing Science |

The mystery surrounding a gruesome disease that affects starfish on the Pacific coast might finally be put to rest. The starfish wasting syndrome — a real disease that is killing off one of the sea's most iconic invertebrates. While the disease has affected starfish (also known as sea stars) for decades, scientists have long puzzled over what might be causing it. Now, one group of researchers may finally have the answer.

The disease is most likely caused by a virus, according to the researchers, who represent a number of institutions, including Cornell University and the University of California, Santa Cruz. Specifically, the scientists have linked the disease to a densovirus (Parvoviridae), which currently affects at least 20 species of starfish on the Pacific coast of North America.

Starfish wasting disease was first identified in 1979, but since then, no one has been able to pin down a precise cause, according to Pete Raimondi, a professor of ecology and evolutionary biology at UC Santa Cruz and co-author of the new sea star study. Scientists long believed that outbreaks of the disease — which occurred in 1983, 1998 and most recently starting in 2013 — may be linked to environmental stressors, such as spikes in ocean temperature or pollution from shipping lanes and marinas. But while such stressors may have something to do with the rapid spread of sea star wasting syndrome, the researchers now think the underlying cause of the disease is the waterborne densovirus.

"What convinced me that this was an infectious agent was that sea stars that had been in captivity in public aquariums for 30 years suddenly died," said Ian Hewson, an associate professor of microbiology at Cornell and lead author of the study. "There was good evidence that it was something coming in through the intake for the aquariums that wasn't being removed by the sand filtration. And [aquariums] receiving UV-treated water weren't getting sick."

To test this hypothesis, Hewson and his team used a process known as metagenomics, in which genetic material is collected directly from environmental samples and then sequenced in a lab. The researchers collected tissue samples from both healthy starfish and those affected by the wasting disease. They then extracted DNA from these samples and tried to figure out how the healthy tissue differed from the infected tissue. The difference between the two kinds of samples soon became clear: the infected tissue contained a densovirus, Hewson said.

With sea stars in hand, the researchers determined which of the animals were infected with the virus. They then measured how much of the virus was present in the animal's tissue per unit of weight— a measurement known as viral load. Ultimately, they found a significant association between the presence of the disease and the abundance of the viral tissue, according to Hewson. The researchers believe this association supports their hypothesis that the wasting disease is caused by the sea-star associated densovirus.

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The Role of Long-Distance Travel in the Spread of Epidemics Like Ebola

The Role of Long-Distance Travel in the Spread of Epidemics Like Ebola | Amazing Science |

The current Ebola outbreak shows how quickly diseases can spread with global jet travel. Yet, knowing how to predict the spread of these epidemics is still uncertain, because the complicated models used are not fully understood, says a University of California, Berkeley biophysicist.

Using a very simple model of disease spread, Oskar Hallatschek, assistant professor of physics, proved that one common assumption is actually wrong. Most models have taken for granted that if disease vectors, such as humans, have any chance of “jumping” outside the initial outbreak area – by plane or train, for example – the outbreak quickly metastasizes into an epidemic.

Hallatschek and coauthor Daniel S. Fisher of Stanford University found instead that if the chance of long-distance dispersal is low enough, the disease spreads quite slowly, like a wave rippling out from the initial outbreak. This type of spread was common centuries ago when humans rarely traveled. The Black Death spread through 14th century Europe as a wave, for example.

But if the chance of jumping is above a threshold level – which is often the situation today with frequent air travel –the diseases can generate enough satellite outbreaks to spread like wildfire. And the greater the chance that people can hop around the globe, the faster the spread.

“With our simple model, we clearly show that one of the key factors that controls the spread of infection is how common long-range jumps are in the dispersal of a disease,” said Hallatschek, who is the William H. McAdams Chair in physics and a member of the UC Berkeley arm of the California Institute for Quantitative Biosciences (QB3). “And what matters most are the rare cases of extremely long jumps, the individuals who take plane trips to distant places and potentially spread the disease.”

This new understanding of a simple computer model of disease spread will help epidemiologists understand the more complex models now used to predict the spread of epidemics, he said, but also help scientists understand the spread of cancer metastases, genetic mutations in animal or human populations, invasive species, wildfires and even rumors.

The paper is published in the Proceedings of the National Academy of Sciences, 2014.

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Modern wine owes a significant part of its genetic heritage to 30-million-year-old plant viruses

Modern wine owes a significant part of its genetic heritage to 30-million-year-old plant viruses | Amazing Science |
Next time you pour a glass of wine, raise a toast to the 30-milion-year-old viruses that have contributed to the genetic make-up of modern grapes.

A team of UQ-led plant scientists has discovered that the Pinot Noir grape variety owes a significant part of its genetic heritage to ancient plant viruses.

In a study published in Nature Communications, Dr Andrew Geering and colleagues have mapped the presence of 30-million-year-old viruses in Pinot Noir DNA. Viruses are usually a curse to farmers because of the damage they cause to crops, but this study also suggests they play a vital evolutionary role.

Dr Geering, a plant pathologist at the UQ's Queensland Alliance for Agriculture and Food Innovation, said most flowering plant species, even the most primitive ones, contain sequence signatures of viruses in their genetic material.

"Animals can move to avoid threats but because plants are anchored to the ground they are obliged to adapt to environmental pressures, such as those brought about by drought or grazing, using novel strategies.

"Plants cope with such threats by acquiring new biochemical pathways or growth habits."

"Pulling new genetic material from the environment, such as from viruses that infect the plant, means evolution can be sped up considerably."

Much like humans, plants are regularly exposed to harmful chemicals or radiation, which can cause damaging and heritable mutations to their genes which, if left unrepaired, could be lethal to their descendants.

"Fortunately, there are special mechanisms to repair these mutations. It's during this repair procedure that foreign DNA such as that originating from viruses can be inserted into the plant's own genetic code, much like using putty to fill a crack in the wall."

"When this happens, the viral DNA can become 'domesticated' if it provides a selective advantage to the plant."

Diane Johnson's curator insight, November 12, 2014 10:40 AM

So interesting. Nice application for genetics studies.

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The Namibian Beetle (Stenocara gracilipes) harvests water from air in one of the driest habitats in the world

The Namibian Beetle (Stenocara gracilipes) harvests water from air in one of the driest habitats in the world | Amazing Science |

Scientists are also actively fighting water scarcity by taking inspiration from the creatures that handle it best. The Namibian Beetle (Stenocara gracilipes) is native to the southwest coast of Africa, one of the driest deserts in the world. The Namib Desert is known for its high temperatures, strong winds, and negligible rainfall, although it does experience fogs that move in from the Atlantic Ocean early in the morning and late at night.

The Namibian Beetle capitalizes on this windborne dew and gains an average of about twelve percent of its body weight through a technique known as fog-basking. When fog-basking, the beetle points its back at the oncoming breeze carrying the tiny dewdrops and waits. The back of the beetle is hydrophobic, but spotted with small hydrophilic bumps. When the dew-carrying breeze blows by, tiny water droplets are attracted to the hydrophilic bumps and condense, accumulating on the beetle’s back.

When the drops grow to a substantial size, the weight of the droplets and the force of the wind exceed the hydrophilic forces and the drops fall down the hydrophobic back, finally sliding into the beetle’s mouth. Products like fog nets have been enlisted to help solve human water scarcity, but mimicking the beetle’s perfectly efficient biology can help scientists confront the water issue more effectively.

Andrew R. Parker, a zoologist at the University of Oxford, and Chris R. Lawrence, an investigator at the defense research firm QinetiQ, headquartered in Farnborough, England, discovered that Stenocarabeetles take advantage of those basic properties of water. On the beetle’s elytra—its hardened, outer pair of wings—there is a pattern that alternates hydrophilic bumps, just one-fiftieth of an inch across, with waxy, hydrophobic (water-averse) valleys. A fog droplet collects on each little bump, and further droplets attach to the first. The droplets coalesce and grow until they reach about two-tenths of an inch in diameter. At that size, because the insect’s back slopes at roughly forty-five degrees to the horizontal, the drops are heavy enough to unstick from the bumps and buck the wind. Each drop slides down the wings toward the beetle’s mouth like a bead of rain on the hood of a freshly waxed car.

It’s a neat trick, but it hardly seems practical to have teeming hoards of beetles harvesting fog for water. What would you do with them for the fogless rest of the day? And how would you keep them from drinking the water themselves, rather than donating it to crops, livestock, or people? Fortunately, Parker and Lawrence have a solution. They developed a surface to mimic the beetle’s elytra that seems to work as well as the beetle’s wings do. The two investigators partly embedded dozens of glass spheres, each about the diameter of a poppy seed, in a thin layer of wax. After de-waxing the top of each glass sphere with alcohol, they had an array of hydrophilic bumps in a hydrophobic field. In tests, they found that neatly ordered arrays of beads caught more mist than random, disordered ones did. But both kinds of array caught more than did smooth, waxy surfaces; most water drops just bounced off the latter. Water landing on bare glass drained in unpredictable directions.

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DNA surviving space flight and 1000˚C re-entry temperatures into Earth's atmosphere

DNA surviving space flight and 1000˚C re-entry temperatures into Earth's atmosphere | Amazing Science |

DNA can survive a flight through space and re-entry into the earth’s atmosphere and still pass on genetic information, scientists from the University of Zurich (UZH) found during a March 2011 experiment on the TEXUS-49 research rocket, the researchers reported in the journal PLOS ONE (open access) Thursday (Nov. 26, 2014).

The researchers applied plasmid DNA molecules to the outer shell of the payload section of a rocket using pipettes. Surviving space flight, 1000°C temperatures, re-entry into Earth’s atmosphere, and landing, about half of the DNA molecules were still found on all the application points on the rocket.

In addition, up to 35% of the DNA retained its full biological function (mediating antibiotic resistance in bacteria and fluorescent marker expression in cells). DNA salvaged was even still able to transfer genetic information to bacterial and connective tissue cells.

“This study provides experimental evidence that the DNA’s genetic information is essentially capable of surviving the extreme conditions of space and the re-entry into Earth’s dense atmosphere,” says study head Professor Oliver Ullrich from the UZH Institute of Anatomy.

The additional experiment was intended to answer the question: “could the outer structure of the rocket be suitable for stability tests on biosignatures — molecules that can prove the existence of past or present extraterrestrial life,” explains Cora S. Thiel of the UZH Institute of Anatomy, Faculty of Medicine.

The researchers say the study reveals that genetic information from the DNA can essentially withstand the most extreme conditions, supporting the speculation that DNA could reach us from outer space in extraterrestrial material made of dust and meteorites, for instance, around 100 tons of which hits our planet every day.

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Rare Black Sea Anlerfish Caught on Film for the First Time

Rare Black Sea Anlerfish Caught on Film for the First Time | Amazing Science |

Made famous in the movie Finding Nemo, a sea devil is caught on film for the first time. The anglerfish survived capture and is now being studied in a specially equipped laboratory.

With its gaping mouth, needle-sharp teeth, and slightly startled expression, the black sea devil anglerfish seems tailor-made for the spotlight. And in fact, one particular female got her close-up on November 17 when researchers got footage of this rare anglerfish—the first time this species has been filmed alive and in its natural habitat—off of central California.

A team using a remotely operated vehicle (ROV) in the Monterey Bay Canyon spied this 3.5-inch-long (9 centimeter) black sea devil about 1,900 feet (580 meters) deep. The scientists were then able to bring her up to the surface alive—no mean feat—and have been monitoring the fish ever since. Bruce Robison, a deep-sea ecologist at the Monterey Bay Aquarium Research Institute, has brought up sea devils from the deep before, but never with an ROV. "It came up in absolutely perfect condition," he says.

Having a living animal to study is telling scientists so much more than they could ever have gotten from the dead, preserved specimens floating around various research facilities, Robison explains. "One of the first things that we got back from ichthyologists was astonishment at how the fish uses its dorsal fin to swim," he says. "Nobody had ever seen that." The anglerfish also appeared to be breathing more than expected, given its build, Robison added.

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Vultures evolved an extreme gut to cope with cocktail of deadly microbes

Vultures evolved an extreme gut to cope with cocktail of deadly microbes | Amazing Science |

How is it that vultures can live on a diet of carrion that would at least lead to severe food-poisoning, and more likely kill most other animals? This is the key question behind a recent collaboration between a team of international researchers from Denmark’s Centre for GeoGenetics and Biological Institute at the University of Copenhagen, Aarhus University, the Technical University of Denmark, Copenhagen Zoo and the Smithsonian Institution in the USA. An “acidic” answer to this question is now published in the scientific journal Nature Communications.

When vultures eat lunch they happily strip the rotting carcasses they find back to the bone. And if, however, the animal’s hide is too tough to easily pierce with their beak, they don’t hesitate to enter it using other routes, among them the back entrance – so to speak: via the anus. Although their diet of meat that is both rotting and liberally contaminated with feces would likely kill most other animals, they are apparently immune to the cocktail of deadly microbes within their dinner such as Clostridia, Fuso- and Anthrax-bacteria.

To investigate vultures’ ability to survive eating this putrid cocktail, a group of scientists generated DNA profiles from the community of bacteria living on the face and gut of 50 vultures from the USA. On average, the facial skin of vultures contained DNA from 528 different types of micro-organisms, whereas DNA from only 76 types of micro-organisms were found in the gut.

Michael Roggenbuck explains: "Our results show there has been strong adaptation in vultures when it comes to dealing with the toxic bacteria they digest. On one hand vultures have developed an extremely tough digestive system, which simply acts to destroy the majority of the dangerous bacteria they ingest. On the other hand, vultures also appear to have developed a tolerance towards some of the deadly bacteria – species that would kill other animals actively seem to flourish in the vulture lower intestine."

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40,000-year-old blood brings mammoth cloning closer

40,000-year-old blood brings mammoth cloning closer | Amazing Science |
Mammoth cloning is closer to becoming a reality following the discovery of blood in the best-preserved specimen ever found.

An autopsy on a 40,000-year-old mammoth has yielded blood that could contain enough intact DNA to make cloning possible, galvanising scientists who have been working for years to bring back the extinct elephant relative. Tests are still being conducted on the blood to see if it will yield a complete genome – the genetic code necessary to build an organism.

The mammoth (nicknamed Buttercup) was discovered in 2013 on Maly Lyakhovsky Island in northern Siberia and excavated from the permafrost. The flesh was remarkably well-preserved, and oozed a dark red liquid when scientists cut into it. That liquid has now been confirmed as blood, following an autopsy conducted by scientists including Museum palaeobiologist Dr Tori Herridge.

'As a palaeontologist, you normally have to imagine the extinct animals you work on,' said Dr Herridge. 'So actually coming face-to-face with a mammoth in the flesh, and being up to my elbows in slippery, wet, and frankly rather smelly mammoth liver, counts as one of the most incredible experiences of my life.' The South Korean firm Sooam Biotech Research Foundation is leading the research project.

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Elixir of Youth: Factors Within the Blood of Young Mice Have the Ability to Restore Aspects of Youth in Old Mice

Elixir of Youth: Factors Within the Blood of Young Mice Have the Ability to Restore Aspects of Youth in Old Mice | Amazing Science |

Emerging evidence indicates that there are factors within the blood of young animals that have the ability to restore youthful characteristics to a number of organ systems in older animals. Recent work regarding age-related cardiac hypertrophy identified growth/differentiation factor 11 (GDF11) as one such factor with rejuvenating powers. As animals become older, levels of circulating GDF11 normally decline.

Remarkably, injecting GDF11 into aged mice recapitulates the effects of heterochronic parabiosis, reversing cardiac hypertrophy7. However, it remained unclear whether the effects of GDF11 were unique to the heart.

Sinha et al.8 have now shown that increasing the systemic levels of GDF11 in aged mice also has rejuvenating effects on skeletal muscle. Aged mice injected daily with recombinant GDF11 (rGDF11) for four weeks have greater numbers of satellite cells, the local muscle stem cell population. Moreover, these satellite cells have less DNA damage and generate more myogenic cells in culture. rGDF11 supplementation also improves the in vivo regenerative capacity of satellite cells, resulting in the growth of larger muscle fibers after injury. Treatment with rGDF11 even increases exercise endurance and grip strength, demonstrating that the improvements seen in satellite cells relate to a functional enhancement in muscle performance. While it remains unclear whether these results are due primarily to effects on skeletal muscle, particularly given the known enhancement of cardiac function observed with rGDF11 treatment, this work demonstrates that a single systemic factor can help restore physiological properties of youth.

Studies regarding the rejuvenating capacity of young blood and rGDF11 have also been extended to the aged brain by Katsimpardi et al.9. The authors focused on the adult neural stem cells (NSCs) of the subventricular zone (SVZ) and found that heterochronic parabiosis enhances proliferation of Sox2+ NSCs in the aged mice. SVZ NSCs differentiate into neuroblasts that migrate to the olfactory bulb, and heterochronic parabiosis almost doubles the number of new neurons in the olfactory bulb of aged mice. Interestingly, these mice exhibit improved olfactory discrimination, but whether this behavioral change results directly from the enhanced neurogenesis or more generally to the whole-animal effects of heterochronic parabiosis is not yet known.

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Certain 'memories' pass between generations

Certain 'memories' pass between generations | Amazing Science |

Behavior can be affected by events in previous generations which have been passed on through a form of genetic memory, animal studies suggest. Experiments showed that a traumatic event could affect the DNA in sperm and alter the brains and behaviour of subsequent generations.

A Nature Neuroscience study shows mice trained to avoid a smell passed their aversion on to their "grandchildren". Experts said the results were important for phobia and anxiety research. The animals were trained to fear a smell similar to cherry blossom. The team at the Emory University School of Medicine, in the US, then looked at what was happening inside the sperm.

They showed a section of DNA responsible for sensitivity to the cherry blossom scent was made more active in the mice's sperm. Both the mice's offspring, and their offspring, were "extremely sensitive" to cherry blossom and would avoid the scent, despite never having experienced it in their lives. Changes in brain structure were also found.

"The experiences of a parent, even before conceiving, markedly influence both structure and function in the nervous system of subsequent generations," the report concluded. The findings provide evidence of "trans-generational epigenetic inheritance" - that the environment can affect an individual's genetics, which can in turn be passed on.

Prof Marcus Pembrey, from University College London, said the findings were "highly relevant to phobias, anxiety and post-traumatic stress disorders" and provided "compelling evidence" that a form of memory could be passed between generations. He commented: "It is high time public health researchers took human trans-generational responses seriously. "I suspect we will not understand the rise in neuropsychiatric disorders or obesity, diabetes and metabolic disruptions generally without taking a multigenerational approach."

Dr. Dea Conrad-Curry's curator insight, November 28, 2014 11:41 AM

Interesting...and in my family, anecdotal evidence suggests....

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CrAssphage: Previously Unknown Ancient Gut Virus Lives in Half of World's Population

CrAssphage: Previously Unknown Ancient Gut Virus Lives in Half of World's Population | Amazing Science |

CrAssphage is a bacteriophage (also known as phages or bacterial viruses), a member of a group of viruses that infect bacteria.

Prof Edwards and his colleagues named this virus after the Cross-Assembly (CrAss) software program used to discover it.

Interestingly, CrAssphage was discovered entirely by accident.

While sifting through data from previous studies on gut-inhabiting viruses, the virologists noticed an unusual cluster of viral DNA – about 97,000 base pairs long.

When they checked this discovery against a comprehensive listing of known viruses, they came up empty. They then screened for CrAssphage across the database of the NIH’s Human Microbiome Project, and Argonne National Laboratory’s MG-RAST database, and again found it in abundance in samples.

To prove that CrAssphage they discovered in their data actually exists in nature, the researchers used DNA amplification technique to locate the virus in the original samples used to build NIH’s database.

“So we have a biological proof that the virus they found with the computer actually exists in the samples. This was a new virus that about half the sampled people had in their bodies that nobody knew about,” said Dr John Mokili of San Diego State University, who is a co-author of the paper describing the discovery in the journal Nature Communications.

The fact that CrAssphage is so widespread indicates that it probably isn’t a particularly young virus, either. “As far as we can tell, it’s as old as humans are. We’ve basically found it in every population we’ve looked at,” Prof Edwards said. According to the scientists, CrAssphage infects one of the most common types of gut bacteria, Bacteroidetes.

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New species glowworm found in Peruvian rainforest

New species glowworm found in Peruvian rainforest | Amazing Science |

Wildlife photographer Jeff Cremer has discovered what appears to be a new type of bioluminescent larvae. He told members of the press recently that he was walking near a camp in the Peruvian rainforest at night a few years ago, when he came upon a side of exposed earth upon which there were many little green glowing dots. Taking a closer look, he found that each dot was in fact the glowing head of a worm of some sort. He posted pictures of what he'd found on Reddit which were eventually spotted by entomologist Aaron Pomerantz, with the Tambopata Research Center. After contacting Cremer, Pomerantz made a pilgrimage to see the worms, gathered some samples and set to work studying them. Shortly thereafter, he determined that the worms were the larvae of an unknown type of beetle, likely a type of click beetle.

Further study of the half inch long larvae revealed that the photoluminescence served just a single purpose, attracting prey. They would sit waiting with their jaws spread wide open. When the light they were emitting attracted something, typically ants or termites, the jaws would snap shut capturing the bug thus providing a meal. Pomerantz collected several samples of the larvae and took them back to a lab where they were tested—he and his colleagues found the larvae would snap shut on just about any bug that touched its jaws.

Entomologists still don't know what kind of beetle the larvae would grow into, but are determined to find out—they aren't even sure if they are from known species. There are a lot of different kinds of click beetles, approximately 10,000 species, about 200 of which are known to be bioluminescent. The entomologists believe the larvae get their luminescence from a molecule called Luciferin, which is also found in the compound used by fireflies to light up the night sky.

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Alien Life Could Thrive on 'Supercritical' CO2 Instead of Water

Alien Life Could Thrive on 'Supercritical' CO2 Instead of Water | Amazing Science |

Alien life might flourish on an exotic kind of carbon dioxide, researchers say. This "supercritical" carbon dioxide, which has features of both liquids and gases, could be key to extraterrestrial organisms much as water is to biology on Earth.

Most familiar as a greenhouse gas that traps heat, helping warm the planet, carbon dioxide is exhaled by animals and used by plants in photosynthesis. While it can exist as a solid, liquid and gas, past a critical point of combined temperature and pressure, carbon dioxide can enter a "supercritical" state. Such a supercritical fluid has properties of both liquids and gases. For example, it can dissolve materials like a liquid, but flow like a gas.

The critical point for carbon dioxide is about 88 degrees Fahrenheit (31 degrees Celsius) and about 73 times Earth's atmospheric pressure at sea level. This is about equal in pressure to that found nearly a half-mile (0.8 kilometers) under the ocean's surface. Supercritical carbon dioxide is increasingly used in a variety of applications, such as decaffeinating coffee beans and dry cleaning.

Ordinarily, carbon dioxide is not considered a viable solvent to host the chemical reactions for life, but the properties ofsupercritical fluids can differ quite significantly from the regular versions of those fluids — for instance, while regular water is not acid, supercritical water is acidic. Given how substantially different supercritical carbon dioxide is from regular carbon dioxide in terms of physical and chemical properties, scientists explored whether it could be suitable for life.

"I always have been interested in possibly exotic life and creative adaptations of organisms to extreme environments," said study co-author Dirk Schulze-Makuch, an astrobiologist at Washington State University in Pullman. "Supercritical CO2 is often overlooked, so I felt that someone had to put together something on its biological potential."

The researchers noted that enzymes can be more stable in supercritical carbon dioxide than in water. In addition, supercritical carbon dioxide makes enzymes more specific about the molecules they bind to, leading to fewer unnecessary side reactions.

Surprisingly, a number of species of bacteria are tolerant of supercritical carbon dioxide. Prior research found that several different microbial species and their enzymes are active in the fluid.

In addition, exotic locales on Earth support the idea that life can survive in environments rich in carbon dioxide. Previous studies showed that microbes can live near pockets of liquid carbon dioxide trapped under Earth's oceans.

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Study Shows That Bed Bugs Can Transmit Parasite that Causes Chagas Disease

Study Shows That Bed Bugs Can Transmit Parasite that Causes Chagas Disease | Amazing Science |

The bed bug may be just as dangerous as its sinister cousin, the triatomine, or “kissing” bug. A new study from Penn Medicine researchers in the Center for Clinical Epidemiology and Biostatistics demonstrated that bed bugs, like the triatomines, can transmit Trypanosoma cruzi, the parasite that causes Chagas disease, one of the most prevalent and deadly diseases in the Americas.

The role of the bloodsucking triatomine bugs as vectors of Chagas disease—which affects 6 to 8 million worldwide, mostly in Latin America, and kills about 50,000 a year—has long been recognized. The insects infect people not through their bite but feces, which they deposit on their sleeping host, often around the face, after feeding. Bed bugs, on the other hand, are usually considered disease-free nuisances whose victims are left with only itchy welts from bites and sleepless nights.

In a study published online this week in the American Journal of Tropical Medicine and Hygiene, senior author Michael Z. Levy, PhD, assistant professor in the department of Biostatistics and Epidemiology at the University of Pennsylvania’s Perelman School of Medicine, and researchers at the Universidad Peruana Cayetano Heredia in Peru conducted a series of laboratory experiments that demonstrated bi-directional transmission of T. cruzi between mice and bed bugs.

In the first experiment run at the Zoonotic Disease Research Center in Arequipa, Peru, the researchers exposed 10 mice infected with the parasite to 20 uninfected bed bugs every three days for a month. Of about 2,000 bed bugs used in the experiment, the majority acquired T. cruzi after feeding on the mice.  In a separate experiment to test transmission from bug to mouse, they found that 9 out of 12 (75 percent) uninfected mice acquired the parasite after each one lived for 30 days with 20 infected bed bugs. 

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The battle of the sexes is waged using RNA scissors encoded on the Y chromosome, at least in persimmons

The battle of the sexes is waged using RNA scissors encoded on the Y chromosome, at least in persimmons | Amazing Science |

Persimmons are among the small club of plants with separate sexes—individual trees are either male or female. Now scientists at Kyoto University and the University of California, Davis have discovered how sex is determined in a species of persimmon, potentially opening up new possibilities in plant breeding. The work has been published in the journal Science.

Most plants have both male and female sex organs in the same individual. Some, like tomato, rice, beans and other cultivated species, cast pollen from male to female organs in the same flower. Others employ ingenious schemes to ensure that one individual pollinates the flower of another. Only about five percent of plant species have separate sexes, a condition called dioecy, or “two houses.”

“Think of it as nature’s best trick to ensure that reproduction involves two individuals, thus maximizing the mixing of genes. Persimmon, pistachio, wild grapevine, kiwi, hops, spinach and even marijuana are dioecious,” said Luca Comai, professor of plant biology at UC Davis and senior author on the paper.

In mammals, sex is determined by X and Y chromosomes: Males have an X and a Y; females have two X’s. A single gene on the Y is responsible for triggering the development of male traits. Most dioecious plants resemble the human system, with XY males and XX females. What gene may be responsible for determining plant sex has been a long-standing mystery.

Working on a family of persimmon trees (Diospyros lotus) established by Professor Ryutaro Tao at Kyoto University, researchers combed through the genomes of some of these trees looking for genes that were exclusive to males. They found an unusual gene they called OGI (Japanese for male tree). Unlike most genes, OGI does not encode a protein, they found. Instead, it codes for a very small piece of RNA that acts as “molecular scissors,” cutting down expression of another gene, called MeGI (Japanese for female tree).

In females, MeGI builds to high level and acts like a neutering agent, repressing pollen formation. In males, OGI prevents accumulation of MeGI. Regulation by RNA scissors can be fickle, and this may help explain why plants that are genetically one sex but functionally another can arise in dioecious species.

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X-ray study shows protein switch for programmed cell death in motion

X-ray study shows protein switch for programmed cell death in motion | Amazing Science |

A study conducted in part at the Department of Energy's SLAC National Accelerator Laboratory has revealed how a key human protein switches from a form that protects cells to a form that kills them – a property that scientists hope to exploit as a 'kill switch' for cancer.

The protein, called cIAP1, shields cells from programmed cell death, or apoptosis – a naturally occurring crackdown on unhealthy cells and tissues. When a cell is in trouble, a signal activates cIAP1, which rapidly transforms into a state that allows apoptosis to take place.  

"Cancer cells produce excess amounts of cIAP1 in an attempt to shut down apoptosis and evade death," says senior staff scientist Thomas Weiss from SLAC's Stanford Synchrotron Radiation Lightsource (SSRL), a DOE Office of Science User Facility, who participated in the study. "The search for drugs that would switch apoptosis back on to eradicate cancer is a very active research field."

The researchers used X-rays from SSRL to watch in real time how cIAP1 transitions from one state to another. The results are an important step towards becoming able to control the protein's switching properties.

"Our study closely ties cIAP1's motions to its role as a switch," says Allyn Schoeffler, a senior research associate at Genentech Inc. in South San Francisco and lead author of the study, published Nov. 10 in Nature Structural & Molecular Biology. "We now know why cIAP1 can act as a strictly controlled fail-safe for apoptosis and, at the same time, remain flexible enough to undergo rapid structural transitions."

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