Archive for the ‘Yale University’ Category

Rothman

STOCKHOLM (AP) — Two Americans and a German-American won the Nobel Prize in medicine on Monday for discovering how key substances are transported within cells, a process involved in such important activities as brain cell communication and the release of insulin.

James Rothman, 62, of Yale University, Randy Schekman, 64, of the University of California, Berkeley, and Dr. Thomas Sudhof, 57, of Stanford University shared the $1.2 million prize for their research on how tiny bubbles called vesicles act as cargo carriers inside cells.

This traffic control system ensures that the cargo is delivered to the right place at the right time and keeps activities inside cells from descending into chaos, the committee said. Defects can be harmful, leading to neurological diseases, diabetes and disorders affecting the immune system.

“Imagine hundreds of thousands of people who are traveling around hundreds of miles of streets; how are they going to find the right way? Where will the bus stop and open its doors so that people can get out?” Nobel committee secretary Goran Hansson said. “There are similar problems in the cell.”

The winners’ discoveries in the 1970s, ’80s and ’90s have helped doctors diagnose a severe form of epilepsy and immune deficiency diseases in children, Hansson said. In the future, scientists hope the research could lead to medicines against more common types of epilepsy, diabetes and other metabolism deficiencies, he added.

Schekman said he was awakened at 1 a.m. at his home in California by the chairman of the prize committee, just as he was suffering from jetlag after returning from a trip to Germany the night before.

“I wasn’t thinking too straight. I didn’t have anything elegant to say,” he told The Associated Press. “All I could say was ‘Oh my God,’ and that was that.”

He called the prize a wonderful acknowledgment of the work he and his students had done and said he knew it would change his life.

“I called my lab manager and I told him to go buy a couple bottles of Champagne and expect to have a celebration with my lab,” he said.

In the 1970s, Schekman discovered a set of genes that were required for vesicle transport, while Rothman revealed in the 1980s and 1990s how vesicles delivered their cargo to the right places. Also in the ’90s, Sudhof identified the machinery that controls when vesicles release chemical messengers from one brain cell that let it communicate with another.

“This is not an overnight thing. Most of it has been accomplished and developed over many years, if not decades,” Rothman told the AP.

Rothman said he lost grant money for the work recognized by the Nobel committee, but he will now reapply, hoping the Nobel prize will make a difference in receiving funding.

Sudhof, who was born in Germany but moved to the U.S. in 1983 and also has U.S. citizenship, told the AP he received the call from the committee while driving toward the city of Baeza, in southern Spain, where he was due to give a talk.

“I got the call while I was driving and like a good citizen I pulled over and picked up the phone,” he said. “To be honest, I thought at first it was a joke. I have a lot of friends who might play these kinds of tricks.”

The medicine prize kicked off this year’s Nobel announcements. The awards in physics, chemistry, literature, peace and economics will be announced by other prize juries this week and next. Each prize is worth 8 million Swedish kronor ($1.2 million).

Rothman and Schekman won the Albert Lasker Basic Medical Research Award for their research in 2002 — an award often seen as a precursor of a Nobel Prize. Sudhof won the Lasker award this year.

“I might have been just as happy to have been a practicing primary-care doctor,” Sudhof said after winning that prize. “But as a medical student I had interacted with patients suffering from neurodegeneration or acute clinical schizophrenia. It left an indelible mark on my memory.”

Jeremy Berg, former director of the National Institute of General Medical Sciences in Bethesda, Maryland, said Monday’s announcement was “long overdue” and widely expected because the research was “so fundamental, and has driven so much other research.”

Berg, who now directs the Institute for Personalized Medicine at the University of Pittsburgh, said the work provided the intellectual framework that scientists use to study how brain cells communicate and how other cells release hormones. In both cases, vesicles play a key role by delivering their cargo to the cell surface and releasing it to the outside, he told the AP.

So the work has indirectly affected research into virtually all neurological disease as well as other diseases, he said.

Established by Swedish industrialist Alfred Nobel, the Nobel Prizes have been handed out by award committees in Stockholm and Oslo since 1901. The winners always receive their awards on Dec. 10, the anniversary of Nobel’s death in 1896.

Last year’s Nobel medicine award went to Britain’s John Gurdon and Japan’s Shinya Yamanaka for their contributions to stem cell science.

http://news.yahoo.com/americans-german-american-win-medicine-nobel-132221489.html

placenta

After most pregnancies, the placenta is thrown out, having done its job of nourishing and supporting the developing baby.

But a new study raises the possibility that analyzing the placenta after birth may provide clues to a child’s risk for developing autism. The study, which analyzed placentas from 217 births, found that in families at high genetic risk for having an autistic child, placentas were significantly more likely to have abnormal folds and creases.

“It’s quite stark,” said Dr. Cheryl K. Walker, an obstetrician-gynecologist at the Mind Institute at the University of California, Davis, and a co-author of the study, published in the journal Biological Psychiatry. “Placentas from babies at risk for autism, clearly there’s something quite different about them.”

Researchers will not know until at least next year how many of the children, who are between 2 and 5, whose placentas were studied will be found to have autism. Experts said, however, that if researchers find that children with autism had more placental folds, called trophoblast inclusions, visible after birth, the condition could become an early indicator or biomarker for babies at high risk for the disorder.

“It would be really exciting to have a real biomarker and especially one that you can get at birth,” said Dr. Tara Wenger, a researcher at the Center for Autism Research at Children’s Hospital of Philadelphia, who was not involved in the study.

The research potentially marks a new frontier, not only for autism, but also for the significance of the placenta, long considered an after-birth afterthought. Now, only 10 percent to 15 percent of placentas are analyzed, usually after pregnancy complications or a newborn’s death.

Dr. Harvey J. Kliman, a research scientist at the Yale School of Medicine and lead author of the study, said the placenta had typically been given such little respect in the medical community that wanting to study it was considered equivalent to someone in the Navy wanting to scrub ships’ toilets with a toothbrush. But he became fascinated with placentas and noticed that inclusions often occurred with births involving problematic outcomes, usually genetic disorders.

He also noticed that “the more trophoblast inclusions you have, the more severe the abnormality.” In 2006, Dr. Kliman and colleagues published research involving 13 children with autism, finding that their placentas were three times as likely to have inclusions. The new study began when Dr. Kliman, looking for more placentas, contacted the Mind Institute, which is conducting an extensive study, called Marbles, examining potential causes of autism.

“This person came out of the woodwork and said, ‘I want to study trophoblastic inclusions,’ ” Dr. Walker recalled. “Now I’m fairly intelligent and have been an obstetrician for years and I had never heard of them.”

Dr. Walker said she concluded that while “this sounds like a very smart person with a very intriguing hypothesis, I don’t know him and I don’t know how much I trust him.” So she sent him Milky Way bar-size sections of 217 placentas and let him think they all came from babies considered at high risk for autism because an older sibling had the disorder. Only after Dr. Kliman had counted each placenta’s inclusions did she tell him that only 117 placentas came from at-risk babies; the other 100 came from babies with low autism risk.

She reasoned that if Dr. Kliman found that “they all show a lot of inclusions, then maybe he’s a bit overzealous” in trying to link inclusions to autism. But the results, she said, were “astonishing.” More than two-thirds of the low-risk placentas had no inclusions, and none had more than two. But 77 high-risk placentas had inclusions, 48 of them had two or more, including 16 with between 5 and 15 inclusions.

Dr. Walker said that typically between 2 percent and 7 percent of at-risk babies develop autism, and 20 percent to 25 percent have either autism or another developmental delay. She said she is seeing some autism and non-autism diagnoses among the 117 at-risk children in the study, but does not yet know how those cases match with placental inclusions.

Dr. Jonathan L. Hecht, associate professor of pathology at Harvard Medical School, said the study was intriguing and “probably true if it finds an association between these trophoblast inclusions and autism.” But he said that inclusions were the placenta’s way of responding to many kinds of stress, so they might turn out not to be specific enough to predict autism.

Dr. Kliman calls inclusions a “check-engine light, a marker of: something’s wrong, but I don’t know what it is.”

That’s how Chris Mann Sullivan sees it, too. Dr. Sullivan, a behavioral analyst in Morrisville, N.C., was not in the study, but sent her placenta to Dr. Kliman after her daughter Dania, now 3, was born. He found five inclusions. Dr. Sullivan began intensive one-on-one therapy with Dania, who has not been given a diagnosis of autism, but has some relatively mild difficulties.

“What would have happened if I did absolutely nothing, I’m not sure,” Dr. Sullivan said. “I think it’s a great way for parents to say, ‘O.K., we have some risk factors; we’re not going to ignore it.’ ”

http://www.nytimes.com/2013/04/25/health/study-ties-autism-risk-to-creases-in-placenta.html?hpw&_r=0

Thanks to Dr. Rajadhyaksha for bringing this to the attention of the It’s Interesting community.

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The flip of a single molecular switch helps create the mature neuronal connections that allow the brain to bridge the gap between adolescent impressionability and adult stability. Now Yale School of Medicine researchers have reversed the process, recreating a youthful brain that facilitated both learning and healing in the adult mouse.

Scientists have long known that the young and old brains are very different. Adolescent brains are more malleable or plastic, which allows them to learn languages more quickly than adults and speeds recovery from brain injuries. The comparative rigidity of the adult brain results in part from the function of a single gene that slows the rapid change in synaptic connections between neurons.

By monitoring the synapses in living mice over weeks and months, Yale researchers have identified the key genetic switch for brain maturation a study released March 6 in the journal Neuron. The Nogo Receptor 1 gene is required to suppress high levels of plasticity in the adolescent brain and create the relatively quiescent levels of plasticity in adulthood. In mice without this gene, juvenile levels of brain plasticity persist throughout adulthood. When researchers blocked the function of this gene in old mice, they reset the old brain to adolescent levels of plasticity.

“These are the molecules the brain needs for the transition from adolescence to adulthood,” said Dr. Stephen Strittmatter. Vincent Coates Professor of Neurology, Professor of Neurobiology and senior author of the paper. “It suggests we can turn back the clock in the adult brain and recover from trauma the way kids recover.”

Rehabilitation after brain injuries like strokes requires that patients re-learn tasks such as moving a hand. Researchers found that adult mice lacking Nogo Receptor recovered from injury as quickly as adolescent mice and mastered new, complex motor tasks more quickly than adults with the receptor.

“This raises the potential that manipulating Nogo Receptor in humans might accelerate and magnify rehabilitation after brain injuries like strokes,” said Feras Akbik, Yale doctoral student who is first author of the study.

Researchers also showed that Nogo Receptor slows loss of memories. Mice without Nogo receptor lost stressful memories more quickly, suggesting that manipulating the receptor could help treat post-traumatic stress disorder.

“We know a lot about the early development of the brain,” Strittmatter said, “But we know amazingly little about what happens in the brain during late adolescence.”

Other Yale authors are: Sarah M. Bhagat, Pujan R. Patel and William B.J. Cafferty

The study was funded by the National Institutes of Health. Strittmatter is scientific founder of Axerion Therapeutics, which is investigating applications of Nogo research to repair spinal cord damage.

http://news.yale.edu/2013/03/06/flip-single-molecular-switch-makes-old-brain-young

sn-amasia

Over the next few hundred million years, the Arctic Ocean and the Caribbean Sea will disappear, and Asia will crash into the Americas forming a supercontinent that will stretch across much of the Northern Hemisphere. That’s the conclusion of a new analysis of the movements of these giant landmasses.

Unlike in today’s world, where a variety of tectonic plates move across Earth’s surface carrying the bits of crust that we recognize as continents, ancient Earth was home to supercontinents, which combined most if not all major landmasses into one. Previous studies suggest that supercontinents last about 100 million years or so before they break apart, setting the pieces adrift to start another cycle.

The geological record reveals that in the past 2 billion years or so, there have been three supercontinents, says Ross Mitchell, a geophysicist at Yale University. The oldest known supercontinent, Nuna, came together about 1.8 billion years ago. The next, Rodinia, existed about 1 billion years ago, and the most recent, Pangaea, came together about 300 million years ago. In the lengthy intervals between supercontinents, continent-sized-and-smaller landmasses drifted individually via plate tectonics, as they do today.

Scientists can track the comings and goings of those landmasses by analyzing the iron-bearing magnetic minerals in various types of rock deposits. That’s because the iron atoms, and sometimes even tiny magnetized bits of iron-bearing rock, line up with Earth’s magnetic field when they’re free to rotate, as they are when the material that contains them is molten. Once the rocks have solidified—and if they aren’t heated above the temperature at which their magnetic information is wiped clean—careful analyses can reveal where on Earth those rocks were when they first cooled, even if the rocks are hundreds of millions of years old. In particular, the rocks retain a record of their paleolatitude, or how far they were from Earth’s magnetic pole.

Although supercontinents before Nuna may have existed, rocks more than 2 billion years old that still preserve evidence of ancient magnetic fields are scarce, Mitchell says. And although scientists have generally agreed that Nuna, Rodinia, and Pangaea existed, exactly where on Earth each came together has been a matter of strong debate. Some geophysical models have suggested that drifting landmasses have come together in the same spot on Earth’s surface each cycle. Other teams have proposed that the wandering pieces reassembled on the opposite side of the planet, 180° away from where the previous supercontinent broke apart.

Now, Mitchell and his colleagues suggest an intermediate answer—that each supercontinent has come together about 90° away from its predecessor. The team’s analyses, reported online today in Nature, use techniques that determine the paleolatitude of ancient landmasses but also, for the first time, estimate their paleolongitude by taking into account how the locations of Earth’s magnetic poles changed through time. Together, these data suggest that the geographic center of Rodinia was located about 88° away from the center of Nuna, and the center of Pangaea—which was located near present-day Africa—sat about 87° from Rodinia’s center.

These angles are no accident, the researchers suggest: The drifting pieces of crust eventually come together along the former edge of the fractured supercontinent—an area approximately 90° away from the former supercontinent’s center. That’s where relatively dense ocean crust was being shoved beneath the lighter continental crust, causing a downward flow in the underlying mantle that in turn attracted the drifting bits like water running down a drain.

According to this model, the next supercontinent—a sprawling landmass dubbed Amasia, which in its earliest stages will merge Asia with the Americas—will stretch across much of the Northern Hemisphere, the researchers suggest. Over the next few hundred million years, Mitchell says, the motions of tectonic plates will cause the Arctic Ocean and the Caribbean Sea to disappear, the western edge of South America to crowd up against the eastern seaboard, and Australia to slam into southeastern Asia. It’s unclear whether Antarctica will join the party or be stranded at the South Pole.

“This is a beautiful piece of work,” says Joseph Kirschvink, a geophysicist at California Institute of Technology in Pasadena. Most of the high-quality paleomagnetic data available today has been collected in the past 20 years or so, he notes. “And the more data we have, the more we can recognize the patterns of where chunks of Earth’s crust must have been.”

The team’s ideas about how and where supercontinents form are “reasonable but far from proven,” says Bernhard Steinberger, a geodynamicist at the German Research Centre for Geosciences in Potsdam. Although Mitchell and his colleagues have identified statistical trends in their paleomagnetic analyses, he notes, “the data still just look like clouds of points to me.”

The team’s results “are very impressive,” says Brendan Murphy, a geologist at St. Francis Xavier University in Antigonish, Canada. Because the breakup and assembly of supercontinents is arguably one of the most important cycles in Earth’s biological and geological evolution, the findings will undoubtedly stimulate further research and analyses, he notes. “And even if the new model is wrong,” he adds, “we’ll learn a lot by testing it.”

http://news.sciencemag.org/sciencenow/2012/02/meet-amasia-the-next-supercontin.html

Thanks to Dr. Rajadhyaksha for bringing this to the attention of the It’s Interesting community.

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Researchers have named a newly discovered, prehistoric lizard “Obamadon gracilis” in honor of the 44th president’s toothy grin.

The small, insect-eating lizard was first discovered in eastern Montana in 1974, but a recent re-examination showed the fossil had been wrongly classified as a Leptochamops denticulatus and was in fact a new species, researchers told Reuters on Tuesday.

Obamadon gracilis was one of nine newly discovered species reported on Monday in the Proceedings of the National Academy of Sciences.

In naming the new species, scientists from Yale and Harvard universities combined the Latin “Obamadon” for “Obama’s teeth” and “gracilis,” which means slender.

“The lizard has these very tall, straight teeth and Obama has these tall, straight incisors and a great smile,” said Nick Longrich, a paleontologist at the school in New Haven, Connecticut.

It was believed to have lived during the Cretaceous period, which began 145.5 million years ago. Along with many dinosaurs from that era, the lizard died out about 65 million years ago when a giant asteroid struck earth, scientists say.

Longrich said he waited until after the recent U.S. election to name the lizard.

“It would look like we were kicking him when he’s down if he lost and we named this extinct lizard after him,” he said in an interview.

“Romneydon” was never under consideration and “Clintondon” didn’t sound good, said Longrich, who supported Hillary Clinton’s failed run against Obama in the 2008 Democratic primary.

Obama is not the first politician whose name has been used to help classify organisms. Megalonyxx jeffersonii, an extinct species of plant-eating ground sloth, was named in honor of President Thomas Jefferson, an amateur paleontologist who studied the mammal.

Earlier this year, researchers announced they had named five newly identified species of freshwater perch after Obama, Bill Clinton, Al Gore, Jimmy Carter and Theodore Roosevelt.

In 2005, entomologists named three species of North American slime-mold beetles agathidium bushi, agathidium cheneyi and agathidium rumsfeldi in honor of George W. Bush, Dick Cheney, and Donald Rumsfeld – the U.S. president, vice president and secretary of defense at the time.

Other celebrity names also have been used to name new species. A small Caribbean crustacean has been named after reggae icon Bob Marley, an Australian horsefly has been named in honor of hip-hop star Beyonce, and an endangered species of marsh rabbit has been named after Playboy magazine founder Hugh Hefner.

http://news.yahoo.com/yale-names-toothy-dinosaur-obamadon-smiling-president-200415370.html

 

Humans share about 99 percent of our genomes with chimpanzees. Now, research finds we share something else: gut bacteria.

The bacterial colonies that populate the chimpanzee intestinal tract are mirror images of those found in the human gut, researchers report today (Nov. 13) in the journal Nature Communications. The findings suggest gut bacteria patterns evolved before chimps and humans split and went their evolutionarily separate ways.

Human gut bacteria are crucial to health, with infants relying on healthy microbe populations to influence the developing immune system. Problems with microbe populations may also contribute to obesity and inflammatory bowel diseases. 

Three intestinal ecosystems

In 2011, researchers learned that everyone’s gut bacteria fall into one of three different types, almost analogous to blood types. In each type, certain bacteria dominate. These types weren’t linked to any personal characteristics such as geographic area, age or gender. Researchers dubbed these distinct bacterial ecosystems “enterotypes.” (“Entero” means gut or intestine.)

“No one really knows why these three enterotypes exist,” said study researcher Andrew Moeller, a doctoral student at Yale University.

Along with his adviser Howard Ochman and their colleagues, Moeller want to understand how these enterotypes arose. They could be distinctly human, he told LiveScience, which would suggest they arose relatively recently, perhaps in response to the development of agriculture. Or they could be ancient, shared among our closest primate relatives.

The researchers analyzed gut bacteria samples from 35 chimpanzees from Gombe Stream National Park in Tanzania. The chimpanzees were all in the subspecies Pan troglodytes schweinfurthii, the eastern chimpanzee, which arose approximately the same time as Homo sapiens.

Shared bacteria

The researchers found that, just like humans, chimps’ guts harbor one of three distinct types of bacterial colonies. Even more intriguingly, these enterotypes matched humans’ precisely. In type 1, for example, both humans and chimps show a predominance of Bacteroides, Faecalibacterium and Parabacteroides.

There were some differences. For example, in humans and chimps, enterotype 2 is marked by an overabundance of bacteria called Lachnospiraceae. In humans, the bacteria Prevotellae is also prevalent in type 2. In chimps, Prevotellae appears in significant numbers in all three enterotypes, perhaps because it is associated with a high-carbohydrate diet.

Other differences could help explain certain human health issues. By comparing human and chimpanzee gut bacteria, the researchers found many of the bacteria present only in humans are linked to diseases such as inflammatory bowel diseases, conditions that cause pain, diarrhea and vomiting.

Seven of the chimps in the study were tested repeatedly over eight years, and their gut microbes were found to change from type to type over that time period. No one has ever tested humans for changes over a period longer than two weeks, Moeller said, but the results suggest our enterotypes may shift over time, too.

Our shared history

The similarities between chimp and human colonies suggest enterotypes predate our species, which in turn suggests that none of the three ecosystems are better than the others, Moeller said. [Gallery: Tiny, Nasty Bugs That Make Us Sick]

“Before we found this in chimpanzees, there was a possibility that enterotypes were a product of modernization, which could mean they have some negative effects on health,” he said. “I don’t think there’s any reason to think one enterotype is going to have an effect on health that’s going to be better” than the others.

Moeller and his colleagues are now examining gorilla fecal samples to find out where they stand as slightly more distant primate relatives to humans.

“The next step is to try to find out the processes and mechanisms responsible for producing these three community states,” Moeller said, “which is kind of a lofty goal, but I think more sampling will actually reveal why these communities exist.”

http://www.livescience.com/24738-chimp-human-gut-bacteria-identical.html

Residents of New Haven, Conn., got an eerie Halloween surprise when a famed tree uprooted during Hurricane Sandy, unearthing the bones of a woman who died nearly 200 years ago – and maybe from others who died during the same period.

Around 6 p.m. on Monday the famous tree at New Haven’s Upper Green, named the “Lincoln Oak” after President Abraham Lincoln, was uprooted as Sandy swept through. New Haven resident Katie Carbo was passing by when she saw the back of a skull in the 60- to 70-foot-tall tree’s roots, police said.

Carbo quickly contacted the New Haven police, and soon after detectives were on the scene as a crowd of onlookers formed. Officer David Hartman with the New Haven Police Department told ABCNews.com that the timing of the discovery was particularly striking.

“I found myself standing there, among onlookers saying, ‘Wow this is really cool, the day before Halloween,’” he said.

Detectives from the NHPD’s Bureau of Identification and the state Medical Examiner’s office came to collect the bones, which Hartman said included a spine and rib cage.

New Haven police also contacted staff from Yale University’s anthropology department, Hartman said, and the New Haven Independent shot some images.

The NHPD said that it had not launched a criminal investigation into the discovery, and that the remains were being taken to the medical examiner’s office.

“What we haven’t yet determined is what will happen with the remains,” Hartman said. “This archaeological event that is going on will last for probably about a week, they’re estimating.”

New Haven police said that the bones belonged to a probable victim of yellow fever or smallpox, who likely was buried between 1799 and 1821, when the headstones were removed to New Haven’s Grove Street Cemetery, but the bodies were never relocated.

Later, the New Haven Independent, citing an initial investigation by an anthropologist and a state investigator, reported bones at the scene actually may be from two or more centuries-old skeletons – not just one.

The Lincoln Oak was planted at the town green by Admiral Andrew Hall Foote’s Grand Army of the Republic post, in honor of the 100th anniversary of Lincoln’s birthday in 1909, according to the New Haven police.

Robert S. Greenberg, a local historian, said that the town green is the burial ground for as many as 5,000 to 10,000 bodies.

Hartman said that he learned today that this is actually not the first time this has happened on the historic Upper Green. According to a local historian, the same situation occurred in 1931, when an uprooted tree brought up skeletal remains, he said.

New Haven is not the only place where the dead were unearthed in Sandy’s wake. The Associated Press reported that at a cemetery in Crisfield, Md., two caskets were forced out of their graves, making their sides visible from the grass, after the cement slabs covering the graves became dislodged.

http://abcnews.go.com/blogs/headlines/2012/10/superstorm-sandy-unearths-bones-caskets/

Thanks to Mr. C for bringing this to the attention of the It’s Interesting community.