Tag: human

Chips That Mimic Organs Could Be More Powerful Than Animal Testing

Each year, millions of rats and mice die for the sake of human safety. Scientists studying toxicity in chemicals feed, inject, or spray them on animals to suss out potential ill effects.

But Congress is now finally updating the Toxic Substance Control Act of 1976, which will among other things encourage the Environmental Protection Agency to find alternatives to animal testing.

The updated act, which is expected to pass both houses of Congress soon, asks the EPA to consider a suite of new testing technologies.

Such as high-throughput robots that apply chemicals to cells in petri dishes and algorithms that predict toxicity based on the effects of similar chemicals.

The most ambitious, the most sci-fi of all these technologies, though, is a human body on a chip.

Think mini organs the size of matchboxes—each mimicking a patch of heart muscle or alveoli in the lungs—all connected together by a tiny circulatory system of microfluidic tubes. An entire human body in miniature.

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Indian Stone Tools Could Dramatically Push Back Date When Modern Humans First Left Africa

We are all children of Africa. As members of the hominin species Homo sapiens, you and I are the product of millions of years of shared evolutionary history of life on Earth.

But as a species we are relatively recent, emerging between 400,000 and 300,000 years ago in East Africa from indigenous archaic populations.

Currently, some of the biggest questions facing palaeoanthropology involve trying to work out how and when early humans left the continent. Was it a single dispersal? Or multiple?

A recent discovery of a jawbone fossil in Israel suggests that there could have been a migration as early as about 180,000 years ago.

But a new study, published in the journal Nature, suggests early humans may have left Africa much earlier than that.

The new research reports the discovery of tools from the Middle Palaeolithic (200,000 to 40,000 years ago) in Tamil Nadu, India.

Surprisingly, the tools date back to 385,000 years ago – which is around the same time as this technology is thought to have first developed by archaic or possibly modern humans in Africa.

This challenges the view, backed by most researchers, that modern humans brought these technologies to India less than 140,000 years ago.

Attirampakkam site

Attirampakkam is located on the banks of a stream of the Kortallaiyar River in northeast Tamil Nadu.

Excavations by a team of Indian researchers revealed abundant layers of stone tools trapped within sediments deposited by streams which ran through the area in prehistory.

The site appears to have been sporadically occupied by apes and early hominins predating Homo sapiens from as far back as 1.7m years ago.

Using a dating technique called infrared-stimulated luminescence – which pinpoints the last time that sediment grains were exposed to light – the authors determined that the silts and gravels which contain the tools date to between 385,000 and 172,000 years ago.

These tools chart the transition from the Acheulean handaxe culture, created by archaic humans of the Lower Palaeolithic, to smaller tools.

The latter were produced by a more sophisticated technique called Levallois – involving the production of stone points and blades.

The tools push the date back for the origins of Middle Palaeolithic technology in India.

Previous studies have suggested that this occurred between 140,000 years and 46,000 years ago, possibly as Homo sapiens migrated into the subcontinent.

But what is perhaps more important, is what these dates mean for the emergence of Homo sapiens and our species’ migrations into the rest of the Old World.

And to understand those implications we need to consider fossils from North Africa and how they are associated with hominin species and technology.

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Do You Always Check The Weather Before Going Out? You Should Check The Disease Map Too.

The field of medical geographic information systems (Medical GIS) has become extremely useful in understanding the bigger picture of public health.

The discipline holds a substantial capacity to understand not only differences, but also similarities in population health all over the world.

New diseases and epidemics spread through the world’s population every year.

The discipline of medical geographic information systems (GIS) provides a strong framework for our increasing ability to monitor these diseases and identify their causes.

The field of medical geography has a much longer history than most are aware of, dating back to the first known doctor, Hippocrates, and progressing through the 1900s until today.

The early history leads us to the examination of contemporary examples of GIS, influences on public health, space-time mapping components, and the future of this discipline supported by Big Data.

The evolution of medical GIS from early disease maps to digital maps is a journey long in the making, and continues to evolve.

These maps have enabled us to gain insight about diseases ranging from cholera to cancer, all while increasing the knowledge of worldwide health issues.

As modern technology continues to thrive, medical GIS will remain a lasting approach for understanding populations and the world we live in.

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Scientists Who Have Grown A Human Ear On The Back Of A Rat Say They Will Be Able To Use Them In Humans In Five Years

Human ears to could be ‘grown to order’ within five years, claim Japanese scientists who have unveiled a rat with an ear on its back.

The Tokyo and Kyoto university technology could be used to help children born with facial abnormalities, as well as youngsters mauled by dogs.

Adults, including soldiers injured in battle of people who have suffered accidents, could also benefit. At the moment, replacement ears are sculpted from cartilage taken from the patient’s ribs.

However, multiple operations are needed, plus the removal of the cartilage is painful and chest never fully heals.

In contrast, the new technique would require just a small sample of cells as starting material. Plus, the finished ear would be a living thing and so should grow with the child.

The scientists began by turning human stem cells – ‘master cells’ – into cartilage cells.

The lab-grown cartilage was then formed into tiny balls and placed in inside plastic tubes shaped like a human ear on a rat’s back.

After two months, the framework dissolved, leaving behind what looks like a two-inch hear lying flat against the animal’s back.

The technique is one of several being perfected around the world, in the aim of making bespoke replacements for body parts damaged by accidents, ravaged by disease or malformed at birth.

Doctors in London have grown a nose from scratch, using the patient’s arm to nurture it, rather than a rat’s back.

They have also built an artificial windpipe and say that eventually it may even be possible to grow a whole face in the lab.

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Scientists Find Jawbone Fossil From Oldest Modern Human Out Of Africa In A Cave In Israel

Scientists on Thursday announced the discovery of a fossilized human jawbone in a collapsed cave in Israel that they said is between 177,000 and 194,000 years old.

If confirmed, the find may rewrite the early migration story of our species, pushing back by about 50,000 years the time that Homo sapiens first ventured out of Africa.

Previous discoveries in Israel had convinced some anthropologists that modern humans began leaving Africa between 90,000 and 120,000 years ago. But the recently dated jawbone is unraveling that narrative.

This would be the earliest modern human anyone has found outside of Africa, ever,” said John Hawks, a paleoanthropologist from the University of Wisconsin, Madison who was not involved in the study.

The upper jawbone — which includes seven intact teeth and one broken incisor, and was described in a paper in the journal Science — provides fossil evidence that lends support to genetic studies that have suggested modern humans moved from Africa far earlier than had been suspected.

Dr. Hawks and other researchers advised caution in interpreting the discovery.

Although this ancient person may have shared some anatomical characteristics with present-day people, this “modern human” would have probably looked much different from anyone living in the world today.

Early modern humans in many respects were not so modern,” said Jean-Jacques Hublin, director of the department of human evolution at the Max Planck Institute for Evolutionary Anthropology in Germany.

Dr. Hublin said that by concluding the jawbone came from a “modern human,” the authors were simply saying that the ancient person was morphologically more closely related to us than to Neanderthals.


That does not mean that this person contributed to the DNA of anyone living today, he added. It is possible that the jawbone belonged to a previously unknown population of Homo sapiens that departed Africa and then died off.

That explanation would need to be tested with DNA samples, which are difficult to collect from fossils found in the arid Levant.

The upper jawbone, or maxilla, was found by a team led by Israel Hershkovitz, a paleoanthropologist at Tel Aviv University and lead author of the new paper, while excavating the Misliya Cave on the western slopes of Mount Carmel in Israel.

The jawbone was discovered in 2002 by a freshman on his first archaeological dig with the group.

The team had long known that ancient people lived in the Misliya Cave, which is a rock shelter with an overhanging ceiling carved into a limestone cliff.

By dating burned flint flakes found at the site, archaeologists had determined that it was occupied between 250,000 to 160,000 years ago, during an era known as the Early Middle Paleolithic.

Evidence, including bedding, showed that the people who lived there used it as a base camp. They hunted deer, gazelles and aurochs, and feasted on turtles, hares and ostrich eggs.

Dr. Hershkovitz and Mina Weinstein-Evron, an archaeologist at the University of Haifa, felt that the jawbone looked modern, but they needed to confirm their hunch.

The Misliya finding is just the latest in a series of discoveries that are changing the story of our evolutionary past.

One study, not yet confirmed, suggested that modern humans may have interbred with Neanderthals in Eurasia about as far back as 220,000 years ago.

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Taking Gene-Editing To The Next Level

Researchers who discovered a molecular “scissors” for snipping genes have now developed a similar approach for targeting and cutting RNA.

The new cutting tool should help researchers better understand RNA’s role in cells and diseases, and some believe it could one day be useful in treatments for illnesses from Huntington’s to heart disease.

To develop the “blades” for the process, researchers led by Feng Zhang at the Broad Institute used CRISPR (clustered regularly interspaced short palindromic repeats)—a system that bacteria evolved to fight off pathogens.

CRISPR has previously been used to edit DNA but had been theorized to work on RNA as well.

The new findings, reported Thursday in Science, came from systematically exploring different aspects of that natural defense system that protects bacteria—and may eventually be put to use helping people.

Nature has already invented all these really interesting mechanisms,” Zhang says, comparing himself with a treasure hunter.

We’re just trying to play with that and learn how they work…then turn them into tools that will be useful to us.


Zhang says the new paper will not affect an ongoing patent dispute over who owns rights to the gene-editing approach known as CRISPR–Cas9. His team was the first to use CRISPR–Cas9 in mammalian cells.

Another team—led by Jennifer Doudna, at the University of California, Berkeley, and French researcher Emmanuelle Charpentier—was first to publish on CRISPR–Cas9, showing its activity in bacteria.

Ironically, Doudna was a co-author on a March paper in Cell that used CRISPR–Cas9 to cut RNA in mammalian cells whereas Zhang’s new paper focuses on bacteria.

The two RNA manipulation methods may be complementary ways to approach the same ends or one may turn out to be more efficient than the other.

In interviews this week each group praised the other’s work while touting the advantages of their own respective approaches.

Zhang says his new method—using the enzyme C2c2 to target RNA—relies on an existing natural system and therefore may be more effective than an approach that requires more manipulation.

Gene Yeo, senior author on the Cell paper, says he has collaborated with both Doudna and Zhang, and described the new paper as a continuation of the kind of “friendly competition” that drives science.

There’s always a bit of a race between a lot of the groups, including mine,” he says. “I think scientific competition is good. People tend to push the boundaries more.

Although Yeo pointed out that the C2c2 system has not yet been shown to work in mammalian cells, Zhang says unpublished results make him optimistic that it will.

Both RNA-targeting approaches have a long way to go before they could be tested in people—but the promise is there, says Yeo, a professor of cellular and molecular medicine at the University of California, San Diego.

Targeting RNA may also offer new insights into how changes in RNA lead to changes in biology and the development of disease.

I think we’ll see an avalanche of these tools that will enable us to monitor and study RNA,” Yeo says.

This helps us think about RNA as not just an intermediate molecule between DNA and protein,” but as a therapeutic tool for treating diseases and problems of development.

Genes consist of double-stranded DNA, which makes single-stranded RNA—which in turn makes the proteins needed for life. Many diseases result from too much or too little protein.

Theoretically, acting on the RNA could push those protein levels up or down, thereby offering treatments.

Manipulating RNA poses fewer ethical concerns than tinkering with the underlying DNA, although gene editing will remain a better approach for treating some diseases.

The problem with DNA editing is that it’s permanent,” Yeo says. “That could be good, but what if you make a mistake?

In some cases, such as with brain cells, DNA repair mechanisms are so strong that it may be more effective to act on the RNA rather than cutting the DNA, says Yeo, who has started a company that’s still in stealth mode to begin looking at treating diseases with this approach.

Zhang says he has long been interested in developing systems to target RNA. His team decided to survey the different kinds of CRISPR systems to figure out their functions.

C2c2 turned out to be an RNA-targeting system, according to the new study, which includes researchers from the National Institutes of Health, Rutgers University and the Skolkovo Institute of Science and Technology in Russia, in addition to Harvard University and Massachusetts Institute of Technology.

Like the Cas9 system that targets specific DNA, C2c2 can be aimed directly at desired RNA sequences, with seemingly few off-target effects.

The reason that it has evolved is to be able to use RNA guides to target RNA,” Zhang says.

His colleague, Eugene Koonin, a co-author on the new paper, puts it more poetically: “Evolution of life to a very large extent is a story of host–parasite interactions,” says Koonin, an expert in evolutionary genomics at the National Center for Biotechnology Information.

As we explore this arms race between host and parasite, we discover more and more intricate, novel ways in which cellular organisms cope with parasites and parasites counteract.

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NASA Plans To Put Nuclear Reactors On MARS To Power A Human Colony

The first humans to settle on Mars could have small nuclear power stations responsible for providing energy.

That’s because NASA is currently working on an £11 million project to develop nuclear fission reactors that could work on the red planet .

The space agency has built several 6.5ft (1.98m) reactors and is due to start testing them here on Earth.

Each reactor splits uranium atoms in half to generate power and, if they pass the initial tests, they could be shipped to Mars to be tested there.

Any human colony on the harsh planet will need power to generate oxygen, water, light, heat and electricity for recharging vehicles and scientific equipment.

Each nuclear reactor can produce up to 10 kilowatts of power – enough to support two people on an expedition mission to the planet.

That’s according to a 2008 paper in which NASA estimated that an eight-person expedition would need 40 kilowatts of power.

This isn’t the first time the US space agency has experimented with nuclear reactors in space.

Back in the 1960s it had a so-called SNAP (Systems for Nuclear Auxiliary Power) program that developed, among other things, the radioisotope thermoelectric generator (RTG).

This is, in effect, a small lump of decaying plutonium-238 that gives off heat and power as it breaks down.

Lee Mason, who oversees power and energy storage technology development at NASA’s Glenn Research Center, said that these new reactors will be the “first time we operate a fission reactor that could be used in space since [the] 1960s SNAP program.”

Successfully installing a power source on Mars is going to be a key part of establishing humans on the planet.

Fission reactors are a better choice than solar panels because of Mars’ distance from the sun and their resistance to the planet’s infamous dust storms.

We’ve landed some really cool things on Mars and they’ve had some pretty remarkable power systems … but they’re not going to cut it for human missions,” Mason said during last month’s Humans to Mars Summit in Washington, D.C.

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People Smell Great! Human Sniffers Sensitive as Dogs’

As you read this, take a whiff. What smells do you detect? How do these smells affect how you feel?

It’s rare that people consciously take in the smells around them, but a new review argues that the human sense of smell is more powerful than it’s usually given credit for, and that it plays a bigger role in human health and behavior than many medical experts realize.

The fact is the sense of smell is just as good in humans as in other mammals, like rodents and dogs,” John McGann, a neuroscientist at Rutgers University-New Brunswick in New Jersey and the author of the new review, said in a statement.

People often think of dogs and rats as the superior sniffers in the animal kingdom, but humans also have an extremely keen sense of smell, McGann argued in the review, which was published last year, May 11 in the journal Science.

In fact, humans can discriminate among 1 trillion different odors, McGann wrote, far more than a commonly cited claim that people can detect only about 10,000 different smells. [10 Things That Make Humans Special]

By overlooking humans’ keen smelling abilities, medicine may be missing a key component of human health, McGann said. S

mell influences human behavior, from stirring up memories to attracting sexual partners to influencing mood to shaping taste, he said.

It’s no coincidence that the French word for smell, “sentir,” also means to feel; emotion and smell are often intricately linked.

It’s true that humans have relatively smaller olfactory organs and fewer odor-detecting genes compared with other animals. However, the power of the human brain more than makes up for this.

When a person smells something, odor molecules bind to receptors in the nose.

These receptors send information about the molecules to the human olfactory bulb in the brain, which then sends signals to other areas of the brain to help identify scents.

This is different from the way smell works in dogs, McGann said. Dogs have a “pump” in their noses that’s designed to take in chemicals in liquid form for identification, he said.

Because the smelling mechanisms are so different, it’s hard to compare humans to dogs, McGann said.

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Ancient Teeth Reveal How Nearly All Of Mexico Was Once Wiped Out By One Of The Most Devastating Food Poisoning Epidemics In Human History

It has been described as one of the most devastating epidemics in human history – and now scientists have discovered what caused it.

An outbreak of a mystery disease in 1576, and second wave in 1576, killed around seven million to 17 million people and helped destroy the mighty Aztec Empire.

Known to the locals as cocoliztli, the symptoms of the disease were horrific; they included red spots on the skin, bleeding from various orifices and vomiting.

A new study of ancient teeth has helped reveal that Aztec’s collapse may have been due to the food poisoning bug salmonella, to which the locals had no resistance.

The study claims this is the first evidence of the bacteria ever found in the South Americas.

When forces led by Spanish conquistador Hernando Cortés arrived in Mexico in 1519, the native population was estimated at about 25 million.

A century later, after a Spanish victory and a series of epidemics, numbers had plunged to around 1 million.

The outbreak impacted large parts of Mexico and Guatemala, including the town of Teposcolula-Yucundaa, located in Oaxaca, Mexico.

Here, archaeological digs unearthed an almost untouched cemetery. Scientists took samples of pulp from inside of the teeth found in skeleton.

They found ten of the skeletons whose burials dated after the conquest tested positive for salmonella. By contrast none of the five skeletons whose burials predated the Spanish conquest tested positive for the disease.

The researchers say the findings make salmonella ‘a strong candidate’ for helping to wipe out the Aztecs and other peoples including the Mixtecs.

The authors said it was conceivable that the disease was brought by European ‘carriers’ who travelled across the Atlantic without suffering the effects.

The type of salmonella led to a condition called enteric fever, which still kills millions around the world today. It is spread by poor sanitation.

It causes high fevers, dehydration, gastrointestinal complications and in serious cases when left untreated, death.

Normally, identifying infectious diseases in skeletons is extremely difficult as they leave no trace.

The team used the Megan Alignment Tool (MALT) to identify DNA sequences from the teeth of individuals buried in a cocoliztili (‘pestilence’ in the indigenous Nahuatl language) cemetery.

This is the first time scientists have recovered molecular evidence of this bacterium using ancient material from the New World.

In the past, scientists usually targeted a particular pathogen or a small set of pathogens.

A key result of this study is that we were successful in recovering information about a microbial infection that was circulating in this population, and we did not need to specify a particular target in advance,” explains Alexander Herbig, also of the MPI-SHH and co-author of the study.

Previous candidates for the lethal disease have included smallpox, viral haemorrhagic fever and even bubonic plague.

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A New Implant Heals Broken Legs by Transforming Into Real Bone

When a bone breaks, medical devices and objects like screws and pins are often used to hold the pieces together while the bone heals.

But this process can be extremely painful, long, and difficult. One new technological marvel might make these methods obsolete.

This potentially game-changing new tool is a 3D printed ceramic implant that holds fractured bones together while turning into actual, natural bone.

Created by Hala Zreiqat at the University of Sydney in Australia and her colleagues, this implant has successfully repaired broken arm bones in rabbits in testing.

Additionally, in a soon-to-be-published study, the team tested this ability with large leg fractures in sheep.

Despite the small sample, the researchers were encouraged by the fact that the experiment was equally successful in all the eight animals involved in the study.

According to the scientists, the sheep were able to walk immediately after surgery where the implant was placed.

However, for four weeks after surgery, the sheep did walk with plaster casts to improve stabilization throughout the healing process.

Three months post-op, the researchers observed complete healing in 25 percent of the fractures, and this rose to 88 percent at the one-year mark.

Additionally, as these bones grew back, the scaffolds of the initial implant dissolved gradually.

So, not only does the implant allow the bone to heal while quite literally creating natural bone in places where it’s missing, but it also dissolves when it is no longer needed.

The implant has a similar composition to natural bone.

So the researchers concluded that it was able to dissolve seamlessly without any toxic side effects and meld into the bone because, “the body can’t tell the difference,” Zreiqat said.

The implant is porous and acts as a scaffold that natural bone and blood vessels can grow through, which makes it a seemingly perfect tool in bone restoration.

This, if it continues to prove successful in testing, would be a drastic improvement to treatment for broken bones.

The sheep in the study were observed to be extremely tolerant of the implants.

Additionally, methods that use bone grafts can be rejected by a patient’s immune system, whereas the ceramic implant tested here was not.

Specifically, the implant is made up of calcium silicate, the mineral granite, and small amounts of strontium and zinc which are trace elements in natural bone.

One downside to the new implants seems to be their rigidity, but for many people the use of these grafts could significantly reduce pain and allow them to heal faster.

The future of medicine will benefit from unique applications of advancing technologies.

3D printing isn’t just for plastics and digital devices. Biological elements can be used within the medical sector to improve the lives of patients, physicians, and the continually developing field.

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