Your fat may help you heal

It frequently happens in science that what you throw away turns out to be most valuable. It happened to Deepak Nagrath, but not for long.
The Rice assistant professor in chemical and biomolecular engineering was looking for ways to grow cells in a scaffold, and he discarded the sticky substance secreted by the cells.
"I thought it was contamination, so I threw the plates away," said Nagrath, then a research associate at Harvard Medical School.

Nagrath, who joined Rice in 2009, and his co-authors have since built a biological scaffold that allows cells to grow and mature. He hopes the new material, when suffused with stem cells, will someday be injected into the human body, where it can repair tissues of many types without fear of rejection.
The research by Nagrath and his co-authors appeared last week in the Federation of American Societies for Experimental Biology (FASEB) Journal.
The basic idea is simple: Prompt fat cells to secrete what bioengineers call "basement membrane." This membrane mimics the architecture tissues naturally use in cell growth, literally a framework to which cells attach while they form a network. When the cells have matured into the desired tissue, they secrete another substance that breaks down and destroys the scaffold.
Structures that support the growth of living cells into tissues are highly valuable to pharmaceutical companies for testing drugs in vitro. Companies commonly use Matrigel, a protein mixture secreted by mouse cancer cells, but for that reason it can't be injected into patients.
"Fat is one thing that is in excess in the body. We can always lose it," Nagrath said. The substance derived from the secretions, called Adipogel, has proven effective for growing hepatocytes, the primary liver cells often used for pharmaceutical testing.
"My approach is to force the cells to secrete a natural matrix," he said. That matrix is a honey-like gel that retains the natural growth factors, cytokines (substances that carry signals between cells) and hormones in the original tissue.
Nagrath's strategy for growing cells isn't the only approach being pursued, even at Rice: Another method reported last week in Nature Nanotechnology uses magnetic levitation to grow three-dimensional cell cultures.

But Nagrath is convinced his strategy is ultimately the most practical for rebuilding tissue in vivo, and not only because it may cost significantly less than Matrigel. "The short-term goal is to use this as a feeder layer for human embryonic stem cells. It's very hard to maintain them in the pluripotent state, where they keep dividing and are self-renewing," he said.
Once that goal is achieved, Adipogel may be just the ticket for transplanting cells to repair organs. "You can use this matrix as an adipogenic scaffold for stem cells and transplant it into the body where an organ is damaged. Then, we hope, these cells and the Adipogel can take over and improve their functionality."
Source <www.scienceblog.com>

Read more »

Meet X-woman: a possible new species of human

The human family tree may be in for a dramatic rewrite. DNA collected from a fossilised finger bone from Siberia shows it belonged to a mysterious ancient hominid – perhaps a new species.

"X-woman", as the creature has been named, last shared an ancestor with humans and Neanderthals about 1 million years ago but is probably different from both species. She lived 30,000 to 50,000 years ago.

"This is the tip of the iceberg," says Chris Stringer, a palaeoanthropologist at the Natural History Museum in London who was not involved in the find. More hominids that are neither Neanderthal nor human are likely to be discovered in coming years, particularly in central and eastern Asia, he says.

Roaming Asia

Previously, anthropologists thought that Neanderthals and humans were the only hominids roaming Europe and Asia during the late Pleistocene. The discovery of 17,000-year-old Homo floresiensis – the "hobbit" – dispelled that notion, but many anthropologists look on H. floresiensis as an anomaly, isolated from the human–Neanderthal hegemony on the mainland.

The newly discovered creature, which probably lived in close proximity to humans and Neanderthals, suggests that things were not that simple. "The picture that's going to emerge in the next years is a much more complex one," says Svante Pääbo, a palaeogeneticist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Pääbo and colleague Johannes Krause discovered the specimen in the Denisova cave in southern Siberia, and sequenced DNA from its mitochondria. It is impossible to say what the creature would have looked like based on a single pinkie bone, so Pääbo and Krause are hesitant to call it a new species.

Though the creature's sex is not known, they are for now referring to her as X-woman because mitochondria are inherited maternally. "No one really knows what she would look like," Pääbo says.

X-woman's mitochondria differ from a human's at nearly 400 DNA letters; Neanderthals show only half as many differences.

Read more here

Read more »

Other Suns and Planets May Provide Better Conditions for Life than Our Own

While our sun and Earth have allowed for the development of a relative bounty of life, many astronomers are starting to believe that the conditions they provide aren't unique, or even ideal, suggesting we may not be alone after all.


At this year's meeting of the General Assembly of the International Astronomical Union, at a panel titled "Solar and Stellar Variability ― impact on Earth and Planets," a multidisciplinary group of experts discussed the evolving research into the types of suns and planets that would be hospitable to the development of life.

Edward Guinan, a professor of astronomy at Villanova University, claims that our sun provided better conditions for the formation of life in its youth. Over four billion years ago, the sun rotated ten times faster than it does today, causing the sun to generate a stronger magnetic field and considerably more radiation than it does today. These conditions have aided the formation of life, but other stars exist that maintain such a rapid rotation for a much longer duration:

Jean-Mathias Grießmeier of ASTRON's research similarly suggests that the Earth may not be an ideal planet for the formation and development of life. Grießmeier examined planetary magnetic fields, finding that a planet with a stronger magnetic field is less likely to have its atmosphere blown away by cosmic debris and is also better able to shield its surface from cosmic radiation. Guinan suggests that planets larger than Earth might be better able to protect any burgeoning life forms:

The Sun does not seem like the perfect star for a system where life might arise. Although it is hard to argue with the Sun's ‘success' as it so far is the only star known to host a planet with life, our studies indicate that the ideal stars to support planets suitable for life for tens of billions of years may be a smaller slower burning ‘orange dwarf' with a longer lifetime than the Sun ― about 20-40 billion years. These stars, also called K stars, are stable stars with a habitable zone that remains in the same place for tens of billions of years. They are 10 times more numerous than the Sun, and may provide the best potential habitat for life in the long run.

Jean-Mathias Grießmeier of ASTRON's research similarly suggests that the Earth may not be an ideal planet for the formation and development of life. Grießmeier examined planetary magnetic fields, finding that a planet with a stronger magnetic field is less likely to have its atmosphere blown away by cosmic debris and is also better able to shield its surface from cosmic radiation. Guinan suggests that planets larger than Earth might be better able to protect any burgeoning life forms:

On the more speculative side we have also found indications that planets like Earth are also not necessarily the best suited for life to thrive. Planets two to three times more massive than the Earth, with a higher gravity, can retain the atmosphere better. They may have a larger liquid iron core giving a stronger magnetic field that protects against the early onslaught of cosmic rays. Furthermore, a larger planet cools more slowly and maintains its magnetic protection. This kind of planet may be more likely to harbour life.

That K stars are relatively common may offer new hope for the possibility of extraterrestrial life, although astronomers are quick to note they don't fully understand how common or fragile life in the universe may be. But their findings do suggest that, on a cosmological scale, Earth can't support life much longer. Says Guinan:

The Earth's period of habitability is nearly over ― on a cosmological timescale. In a half to one billion years the Sun will start to be too luminous and warm for water to exist in liquid form on Earth, leading to a runaway greenhouse effect in less than 2 billion years.

Repost from : http://io9.com

Read more »

We Could Be Discovering Earthlike Planets By 2013

There are probably billions of Earthlike planets in our galaxy alone, predicts scientist Alan Boss. With NASA launching the Kepler satellite, seeking other Earths, you can expect the first discoveries in a few years.


The Kepler satellite will use the same planet-finding method that's already found a few hundred planets outside our solar system: looking for subtle dips in stellar brightness. But it'll use more sensitive methods, looking for smaller, cooler planets that are closer to Earth and more hospitable to life.

Boss, who's just written a new book called The Crowded Universe, argues that Earthlike planets should be quite common:

First, if you talk to astronomers who look at young stars, they will tell you that when stars form, they tend to have a little bit of angular momentum, which means that they can't accrete all of their matter and they end up having a disk around them. Such disks are what planetary systems form out of, basically the leftovers from the star-formation process. Essentially all young stars have these disks, so we expect that these young stars at least have the possibility of having planetary systems.

Second, those who worry about planet-formation processes find that it's very hard to stop Earth-like planets, or some sort of large, rocky object, from forming. Earths in some sense are easier to build than Jupiters, but we already know from our extrasolar planet census that Jupiters exist around at least 10 percent, and probably around 20 percent, of stars. So Earths should be even more common than that.

Finally, and even more directly, the planetary searches are already beginning to find a new class of planets called super-Earths with masses maybe five, 10 or 15 times the mass of Earth that orbit a little closer to their star than our planet does. These guys occur on roughly one third of nearby solar-type stars. And these are sort of the oddballs in some sense, which I think are very much just the tip of the iceberg of the spectrum of Earth-like planets. In any theoretical model of planet formation that people talk about, there should be a ton of Earths compared to these oddball super-Earths, so when we do a complete census we should find a lot of Earths. If these oddballs are there 30 percent of the time and the Jupiters are there 20 percent of the time, that means the ones we can't quite see should be there essentially all the time. So it's a very compelling story, and all the evidence from several different directions points toward Earths being quite common.

He also believes that life is quite tenacious and it's likely that many of these planets have water on them, and comets dumping amino acids and other prebiotic chemicals, making life pretty likely. So many of these Earthlike worlds could turn out to have our alien cousins on them.

Read more »

History of Pizza

The roots of modern pizza come from the ancient Greek colony of Naples in Magna Graecia, which is part of southern Italy.

Although flat breads

had been baked since way back in the Stone Age, it is around 1000 BC that the pizza pie really began its long evolution on the Italian peninsula. In northern Italy, the ancient Etruscans began baking a flat bread beneath stones on a hearth. To add taste, simple toppings consisting of herbs, olive oil, and spices were added after the bread was cooked. This dish was given the name “picea” which in the old Neapolitan dialect means “to pick” or “to pluck,” perhaps referring to the act of plucking this bread out of the oven or to picking at with the hands.

In southern Italy and Sicily where Greek colonists lived, the people improved on the Etruscan picea by cooking the toppings into the bread rather than add them in afterwards. And instead of being a mere side dish as was the case with the Etruscans, the Greeks in Italy made picea a main course for dinner.icking at it with the hands.

For many centuries, picea changed very little. An important catalyst for its change was the discovery of tomatoes in the New World by the Spaniards. Around 1522, tomatoes arrived in Italy via Spain. One roadblock to consuming tomatoes, however, was the widespread belief that tomatoes were poisonous. Fortunately for the pizza lovers of today, the poorer peasants of Naples finally overcame their doubts about tomatoes in the 17th century and began adding it to bread dough when baking their breads and called this dish pizzaioli.

As the tomato

became popular with the Neapolitans, mozzarella cheese was slowly growing in popularity. Mozzarella had become available in Italy after water buffalo were imported from India in the 7th century. It is from water buffalo milk that mozzarella cheese is made. Its popularity grew very slowly until the latter half of 18th century when mozzarella came into widespread use in Italy.

So here we have two of the key ingredients of the modern pizza, tomatoes and mozzarella cheese, yet they did not meet on a pizza until 1889 when Queen Margherita of Savoy ordered Raffaele Esposito, a Neopolitan pizza chef, to make a pizza for a royal party. In an act of patriotism, chef Esposito designed a pizza pie made of red tomatoes, white mozzarella cheese, and green basil to match the colors of the Italian flag. Not only was this pizza visually appealing but Pizza Margherita, as it was called, was a gastronomic hit. And the modern pizza pie was born.

Source < >

Read more »

Nouns and verbs are learned in different parts of the brain

Two Spanish psychologists and a German neurologist have recently shown that the brain that activates when a person learns a new noun is different from the part used when a verb is learnt. The scientists observed this using brain images taken using functional magnetic resonance, according to an article they have published this month in the journal Neuroimage.

"Learning nouns activates the left fusiform gyrus, while learning verbs switches on other regions (the left inferior frontal gyrus and part of the left posterior medial temporal gyrus)", Antoni Rodríguez-Fornells, co-author of the study and an ICREA researcher at the Cognition and Brain Plasticity Unit of the University of Barcelona, tells SINC.

The Catalan researcher, along with psychologist Anna Mestres-Missé, who is currently working at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, and neurologist Thomas F. Münte from the Otto-von-Guericke University in Magdeburg, in Germany, have just published the results of their study confirming the neural differences in the map of the brain when a person learns new nouns and verbs in the journal Neuroimage.

The team knew that many patients with brain damage exhibit dissociation in processing these kinds of words, and that children learn nouns before verbs. Adults also perform better and react faster to nouns during cognitive tests.

Read more here

Read more »

Intelligent people have 'unnatural' preferences and values that are novel in human evolution

More intelligent people are significantly more likely to exhibit social values and religious and political preferences that are novel to the human species in evolutionary history. Specifically, liberalism and atheism, and for men (but not women), preference for sexual exclusivity correlate with higher intelligence, a new study finds.

The study, published in the March 2010 issue of the peer-reviewed scientific journal Social Psychology Quarterly, advances a new theory to explain why people form particular preferences and values. The theory suggests that more intelligent people are more likely than less intelligent people to adopt evolutionarily novel preferences and values, but intelligence does not correlate with preferences and values that are old enough to have been shaped by evolution over millions of years."

"Evolutionarily novel" preferences and values are those that humans are not biologically designed to have and our ancestors probably did not possess. In contrast, those that our ancestors had for millions of years are "evolutionarily familiar."

"General intelligence, the ability to think and reason, endowed our ancestors with advantages in solving evolutionarily novel problems for which they did not have innate solutions," says Satoshi Kanazawa, an evolutionary psychologist at the London School of Economics and Political Science. "As a result, more intelligent people are more likely to recognize and understand such novel entities and situations than less intelligent people, and some of these entities and situations are preferences, values, and lifestyles."

Read more here

Read more »

Thicker brains fend off pain

Montreal, February 24, 2010 – People can reduce their sensitivity to pain by thickening their brain, according to a new study published in a special issue of the American Psychological Association journal, Emotion. Researchers from the Université de Montréal made their discovery by comparing the grey matter thickness of Zen meditators and non-meditators. They found evidence that practicing the centuries-old discipline of Zen can reinforce a central brain region (anterior cingulate) that regulates pain.

"Through training, Zen meditators appear to thicken certain areas of their cortex and this appears to be underlie their lower sensitivity to pain," says lead author Joshua A. Grant, a doctoral student in the Université de Montréal Department of Physiology and Institut universitaire de gériatrie de Montréal. "We found a relationship between cortical thickness and pain sensitivity, which supports our previous study on how Zen meditation regulates pain."

As part of this study, scientists recruited 17 meditators and 18 non-meditators who in addition had never practiced yoga, experienced chronic pain, neurological or psychological illness. Grant and his team, under the direction of Pierre Rainville of the Université de Montréal and the Institut universitaire de gériatrie de Montréal, measured thermal pain sensitivity by applying a heated plate to the calf of participants and followed by scanning the brains of subjects with structural magnetic resonance imaging. According to MRI results, central brain regions that regulate emotion and pain were significantly thicker in meditators compared to non-meditators.

"The often painful posture associated with Zen meditation may lead to thicker cortex and lower pain sensitivity," says Grant, noting that meditative practices could be helpful in general for pain management, for preventing normal age-related grey matter reductions or potentially for any condition where the grey matter is compromised such as stroke.

Source< www.eurekaalert.org >

Read more »