Rick Ross's Simple Lessons for Bosses, Dons, and Bitches
|10:39:13 PM, Thursday, September 29, 2011|
"Real Niggas Don't Send Dick Flicks
It only occurs to me after midnight that it might be past 8 P.M. Normally, due to domestic circumstances, I'm asleep by ten. But it doesn't feel late. Rick Ross lives in his own personal time zone, and when you're around him, you're subject to it. Though I do notice a strange lull in the house, a subtle shift in metabolic state. Ross's bodyguard, a gentle-looking man with sleepy eyes who is nearly seven feet tall, lopes through the kitchen still wearing this strange headset that makes him look like he's getting translation at the U.N. General Assembly. Darren, a kid from Milwaukee, is still in the basement, editing what must be just server-melting amounts of Rick Ross video. I confuse two of the other guys who work for Ross—one's name is Red and the other's is Black, and I think Red wears a black hat. One of them is stripping the tobacco out of several packs of grape Swisher Sweets and then reassembling them into precise blunts. It's mesmerizing, like watching someone who's really good at knitting. But despite all this activity, it feels like the house—the sense of industry that's been ratcheted up for the nine hours I've been here—has slipped into standby mode. It occurs to me that it might be the weed, the same way it feels like you're driving ninety miles an hour when you're crawling along at five. Then it occurs to me that a better explanation is that Rick Ross has disappeared.
In the den, Gucci Pucci, Ross's manager, is lying on one of the black leather sofas. There's a television channel whose programming seems to consist entirely of people getting into car crashes, and Mr. Pucci is watching it.
"Where's Ross?" I ask.
A conversion van plows through the front of a 7-Eleven and surprises a woman buying milk. "Asleep," Pucci says without turning his head. "Or..." Then he makes the "banging someone" gesture with his fist.
It's not hard to figure out who that someone might be. Since I arrived in Atlanta nine hours ago, I have met at least a dozen men at Rick Ross's house/recording studio, all of whom kind of work for him and are also hoping to get their big break from him. But I have met exactly one woman. When I arrived this afternoon, Ross was reclining in a cushioned dining chair wearing camouflage cargo shorts, a blindingly white T-shirt, and giant Louis Vuitton sunglasses. The room was fragrant with cocoa butter, and a slender blonde woman in black leggings had both hands up the legs of his shorts. She had skin that looked like it smelled good and a face like Whitney Houston in 1987. Ross dismissed her wordlessly, with a nod, put one warm paw on my shoulder, and let me know that should there be anything I need, anything, all I had to do was ask. He said the word "anything" like someone who embraced the scope of what that might mean. He spoke in that deep creamy voice that seems to come from six miles down in his chest. A voice you instantly recognize from his music..."
Al-Qaida Calls on Ahmadinejad to End 9/11 Conspiracy Theories
|8:40:54 PM, Thursday, September 29, 2011|
"Al-Qaida has sent a message to the Iranian president, Mahmoud Ahmadinejad, asking him to stop spreading conspiracy theories about the 9/11 attacks.
Iranian media on Wednesday reported quotes from what appears to be an article published in the latest issue of the al-Qaida English language magazine, Inspire, which described Ahmadinejad's remarks over the 11 September attacks as "ridiculous".
In his UN general assembly speech last week, Ahmadinejad cast doubt over the official version of the 2001 attacks.
"The Iranian government has professed on the tongue of its president Ahmadinejad that it does not believe that al-Qaida was behind 9/11 but rather, the US government," the article said, according to Iranian media. "So we may ask the question: why would Iran ascribe to such a ridiculous belief that stands in the face of all logic and evidence?"
Ahmadinejad said in New York that the "mysterious September 11 incident" had been used as a pretext to attack Afghanistan and Iraq. He had also previously expressed scepticism at the US version of events.
"By using their imperialistic media network which is under the influence of colonialism, they threaten anyone who questions the Holocaust and the September 11 event with sanctions and military actions," said Ahmadinejad.
The al-Qaida article insisted it had been behind the attacks and criticised the Iranian president for discrediting the terrorist group.
"For them, al-Qaida was a competitor for the hearts and minds of the disenfranchised Muslims around the world," said the article published in the Inspire magazine. "Al-Qaida … succeeded in what Iran couldn't. Therefore it was necessary for the Iranians to discredit 9/11 and what better way to do so? Conspiracy theories."
Al-Qaida also accused Iran of hypocrisy over its "anti-Americanism"..."
-- He must be hurting their street cred! Talking their balls away... lol
China Prepares to Launch Space Laboratory
|2:06:31 AM, Thursday, September 29, 2011|
"The unmanned, 8.5 ton Tiangong-1 will help to test the technologies that China plans to use in its space station, which is scheduled for completion by 2020. It will also be used as a docking target for the unmanned Shenzhou 8 space craft which is expected to launch by the end of this year. If that mission succeeds, Chinese astronauts could fly to Tiangong-1 next year, dock, and live aboard it.
If China can demonstrate it has a functioning docking system, it could also begin to dock with the International Space Station. China has held up its ambitious space programme as a symbol of its growing technological expertise.
The module's launch arrives just before China's National Day celebrations on October 1.
The mission has been delayed by a few weeks because of "over 170 technical modifications" that had to be made at the launch site in the Gobi desert, according to the director of the site. As China steps up its space programme, in competition with India and Japan, the United States and Russia have both scaled back their ambition.
The US says it will not test a new space rocket to carry out manned missions until 2017 and Russia has said manned mission are no longer a priority.
Meanwhile, China became only the third country to send an astronaut on a spacewalk in 2008 and is planning an unmanned moon landing for next year. It hopes to send a man to the moon by 2020, roughly five decades after the US managed the feat."
Team Finds Stable RNA Nano-Scaffold Within Virus Core
|11:21:46 PM, Wednesday, September 28, 2011|
"With the discovery of a RNA nano-scaffold that remains unusually stable in the body, researchers at the University of Cincinnati (UC) have overcome another barrier to the development of therapeutic RNA nanotechnology.
Peixuan Guo, PhD, Dane and Mary Louise Miller Endowed Chair and professor of biomedical engineering, and his colleagues in UC's College of Engineering and Applied Sciences report the construction of a thermodynamically stable RNA nanoparticle online in the journal Nature Nanotechnology.
The nanoparticle, constructed from a three-way junction (3WJ) motif of packaging RNA (pRNA) molecules, can serve as a platform for building larger, multifunctional nanoparticles, says Guo, which can then be injected into the body to deliver therapeutics to targeted cells.
"RNA nanoparticles have applications in treating cancers and viral infections," he says, "but one of the problems in the field is that RNA nanoparticles are relatively unstable. Without covalent bonds or cross-linking to keep them together, the nanoparticles produced via self assembly can dissociate when injected into animal and human circulation systems, where they exist at very low concentrations."
In the work, Guo and researchers explored the unique structure of the DNA packaging motor of bacteriophage phi29, a virus that infects bacteria. The motor is geared by a ring of pRNA molecules containing interlocking loops and helical domains, which are joined together by a strong 3WJ motif.
"The pRNA is extraordinary strong," says Guo, "since it is a mechanical part that nature uses to gear a powerful motor. This strength makes it an ideal platform for constructing RNA nanoparticles. Furthermore, the core has unique and unusually stable features, such as resistance to strong denaturants like urea and the ability remains intact at ultra-low concentrations in the absence of magnesium."
Using three small fragments of RNA with high affinity for assembling into larger structures, researchers were able to recreate the 3WJ core outside the pRNA structure. In addition, each arm of the 3WJ core can be fused to siRNA molecules, receptor-binding ligands and RNA aptamers, molecular tools necessary for the nanoparticle to find a targeted cell inside the body and silence genes within it.
The resulting nanoparticle remained stable and functional in vitro and, when introduced in vivo, targeted tumors specifically without diffusing to other critical organs or normal tissues..."
Unlike Humans, Chimpanzees Don’t Enjoy Collaborating
|10:48:31 PM, Tuesday, September 27, 2011|
"When it benefits them, chimpanzees willingly work together. Otherwise, they can’t be bothered.
For humans, collaboration is rewarding for its own sake, a behavioral split that may underlie key differences between human and chimpanzee societies.
Primate researchers, working with semi-free ranging chimpanzees at a sanctuary in Uganda, found chimpanzees recruit a helping partner only if it gets them more food than they’d get alone. The study, described in Animal Behavior, Sept. 7, is part of a current trend in primatology to unpick how motivation and mental state affects an animal’s interactions.
“It looks like motivation plays a very important role in how we behave,” said Anke Bullinger, primary author. “And it gives a hint that even though species might be cognitively capable of doing certain things, they might not show the behavior, because they just don’t want to.”
The extent of human cooperation is unique, but not cooperation itself. Chimpanzees, bonobos, elephants, and many birds work together for joint rewards.
“The interesting thing is that there isn’t much research on the motivational aspects of this,” Bullinger said. “I suspect that motivation plays a role in many aspects of cognition, not just in cooperative behavior, but also in social learning, in communication.”
For the study, Bullinger and her colleagues set food boards out of the chimpanzee’s direct reach. To bring the banana-bearing platforms close, the chimps pulled on a rope resting on the ground. Chimpanzees had two options. One board they could pull close solo. On another board, loose rope threaded between loops. To get these boards, both ends had to be pulled, so the chimpanzee had to go get their partner, waiting in an adjoining room..."
More Details on the 'Faster than the Speed of Light' Neutrinos
|1:39:19 AM, Tuesday, September 27, 2011|
"Last night, in response to a worldwide surge in interest, the OPERA experiment released a paper that describes the experiments that appear to show neutrinos traveling faster than the speed of light. And today, CERN broadcast a live seminar in which one of the work's authors described the content of the paper. Both of those emphasized the point of our initial coverage: figuring out whether anything is traveling beyond the speed of light requires incredibly accurate measurements of time and distance, and the OPERA team has made an extensive effort to make its work as accurate as possible.
As a spokesperson for the MINOS neutrino experiment told Ars yesterday, there are three potential sources of error in the timing measurements: distance errors, time-of-flight errors, and errors in the timing of neutrino production. The vast majority of both the paper and the lecture were dedicated to discussing how these errors were reduced (the actual detection of the neutrinos was only a small portion of the paper).
Neutrinos are produced using a proton beam from one of the accelerators that feeds them into the LHC. The protons hit a fixed target and produce unstable particles that decay, releasing a neutrino. The protons move close to, but not at the speed of light, as do the unstable pions; both of these effects were accounted for. The timing of the protons and structure of the two bunches of them used in these experiments is not even, either, so the researchers created a profile of the proton bunch. They also compensated for the timing of the kicker magnet that pushes the bunch out of the accelerator and added detectors that registered them passing through the hardware to get a clearer sense of their timing.
Similar work went into the detector side, where the time between an actual neutrino event and the signal propagating through the hardware and to a field programmable gate array (FPGA) where it was processed was estimated at about 50ns (the neutrinos only arrived 60ns early, so that 50ns is a substantial fraction of the total). But the error in their estimate was only ±2.3ns, as measured by shining a picosecond UV laser on the detector.
Distance travelled created its own problems. The positions of the hardware were measured via GPS, which normally doesn't provide the sort of precision needed for this work. But the labs did multiple samples of the GPS signals, threw out bad ones, compensated for the effect of the Earth's iononsphere, and more. Then, just to check their work, they had a commercial company come in and perform an independent analysis. The end result was a measurement sensitive enough to register both the steady change due to continental drift, as well as a 7cm jump triggered by an earthquake.
Then, the timing of all the events had to be synchronized. At each site, the group put a cesium-based atomic clock, and synchronized it with the GPS signal. Then, they sent a portable atomic clock between the facilities to check. They then ran photons through a fiber optic cable between them, just to make sure.
The end result is that the OPERA team doesn't see any obvious problems in its measurements. All of the errors, when added up, shouldn't be able to account for anything close to the 60ns gap between the neutrinos' arrival and the speed of light. The difference between their speed and that of light is very statistically significant, and the neutrino data itself looks excellent. The team has recorded over 16,000 events now, and the profile of events over time very closely matches the structure of the proton bunches that created them.
But that doesn't mean that this presentation is the last word on the topic. There are a lot of potential sources of error they know about—the paper's table lists a dozen of them. Small errors in each of these could add up to something more significant than their total error. Then there are the classic unknown unknowns. The authors have tried to think of everything, but it's not clear that they can..."
They Ate What? 2011 Pet X-ray Contest Winners
|1:10:18 AM, Tuesday, September 27, 2011|
"Veterinary Practice News would like to thank everyone who sent radiographs in for this year’s competition. Each year we’re amazed at the images and stories that come in—we wish we had room to print them all! We would also like to thank the judge, Matt Wright, DVM, Dipl. ACVR, who had the tough task of selecting a winner.
This year’s winner, Vanessa Hawkins, DVM, will receive a digital single-lens reflex camera courtesy of contest sponsor Sound-Eklin of Carlsbad, Calif. The runners-up will receive a point-and-shoot camera. More entries can be seen at VeterinaryPracticeNews.com/Contest..."
-- Yep, follow the link to see the world's smartest pets!
'First Irish Case' of Death by Spontaneous Combustion
|1:02:06 AM, Tuesday, September 27, 2011|
"A man who burned to death in his home died as a result of spontaneous combustion, an Irish coroner has ruled.
West Galway coroner Dr Ciaran McLoughlin said it was the first time in 25 years of investigating deaths that he had recorded such a verdict.
Michael Faherty, 76, died at his home in Galway on 22 December 2010.
Deaths attributed by some to "spontaneous combustion" occur when a living human body is burned without an apparent external source of ignition.
Typically police or fire investigators find burned corpses but no burned furniture.
An inquest in Galway on Thursday heard how investigators had been baffled as to the cause of Mr Faherty's death at his home at Clareview Park, Ballybane.
Forensic experts found that a fire in the fireplace of the sitting room where the badly burnt body was found, had not been the cause of the blaze that killed Mr Faherty.
The court was told that no trace of an accelerant had been found and there had been nothing to suggest foul play.
The court heard Mr Faherty had been found lying on his back with his head closest to an open fireplace.
The fire had been confined to the sitting room. The only damage was to the body, which was totally burnt, the ceiling above him and the floor underneath him.
Dr McLoughlin said he had consulted medical textbooks and carried out other research in an attempt to find an explanation.
He said Professor Bernard Knight, in his book on forensic pathology, had written about spontaneous combustion and noted that such reported cases were almost always near an open fireplace or chimney..."
Hints of Universal Behavior Seen in Exotic Three-Atom States
|12:56:14 AM, Tuesday, September 27, 2011|
"A novel type of inter-particle binding predicted in 1970 and observed for the first time in 2006, is forming the basis for an intriguing kind of ultracold quantum chemistry. Chilled to nano-kelvin temperatures, cesium atoms -- three at a time -- come together to form a bound state hundreds or even thousands of times larger than individual atoms. Unlike the case of ordinary atoms, wherein electrons are bound to a nucleus in a spectrum of energy levels on the order of an electron volt (that is, it would typically take an eV of energy to free the electron), the cesium triplets feature energy levels that are measured in trillionths of an electron volt (peV). Stranger still, a new experiment observing four such cesium states reports that the states' sizes are roughly the same. This has taken theorists by complete surprise.
In the seventeenth century Isaac Newton derived the classical force laws used to calculate the force between two objects. Calculating the behavior of three-body groupings such as the Moon/Earth/Sun system was much harder; indeed Newton never succeeded. Nowadays such problems can be studied with powerful computers, but only numerical simulations are possible, and not exact, analytical solutions.
In 1970, however, Russian physicist Vitaly Efimov predicted that under some special conditions, three bodies, such as atoms at ultralow temperatures, could be made to enter into stable states whose behavior could be calculated with remarkable ease. Then in 2006 exactly such states were actually observed by scientists at the University of Innsbruck. Now, these researchers have extended their work and demonstrated that the "three-body parameter," used to describe how the three participating bodies interact, varies in a consistent way regardless of the atomic species used.
Paul Julienne, a scientist at the Joint Quantum Institute (JQI), operated by the University of Maryland and the National Institute of Standards and Technology (NIST), contributed theoretical help to the Innsbruck scientists conducting the experiment, a team led by Rudolf Grimm. "None of the experts in three-body physics had expected this kind of universal behavior to show up in these 3-atom systems," Julienne said. "This behavior came as a big surprise." And the universality, in turn, might suggest the existence of some new kind of ultracold chemistry at work.
Efimov's 1970 work met with much skepticism, especially since his prediction specified that three particles could form stable partnerships even though none of the two-particle matchups were stable. That is, 3 particles could accomplish what 2 particles could not. This novel arrangement has been compared to the "Borromean Rings," a set of three rings used on heraldic symbol for the Borromeo family during the Italian Renaissance. The three rings hold together unless any one of the rings is removed..."
Space Storms to Pose Greater Risk to Flyers and Astronauts
|12:45:01 AM, Tuesday, September 27, 2011|
"If you thought the outlook for Earth's climate looked bleak, don't look up. A new study suggests that space weather—the hail of energetic particles above our atmosphere—is set to worsen in coming decades. The grim forecast suggests that astronauts and frequent flyers will face greater radiation hazards and could rule out a crewed mission to Mars before 2050.
Space weather is a general term for the environmental conditions above Earth's atmosphere. When space weather is bad, dangerous particles abound. These include protons and ions, known as galactic cosmic rays (GRCs), raining down at near-light speed from space, and similar particles coming in bursts from the sun, called solar energetic particles (SEPs).
The sun has the biggest impact on space weather. The radiation it emits fluctuates both over the short term and across centuries. When the sun is emitting more radiation, it generates a strong external magnetic field, which swaddles the solar system in the "heliosphere"—a shield against GRCs. On the downside, a more active sun is thought to emit SEPs more consistently. Currently, the sun's activity seems to be fading from a "grand maximum" that has been with us since the 1920s, suggesting a new minimum is upon us.
Although that might seem like good news, it's actually not, according to space meteorologist Michael Lockwood of the University of Reading in the United Kingdom and colleagues. Lockwood's group has analyzed how variations in GRCs and SEPs reaching Earth have correlated with the sun's activity over hundreds of years. No one was recording the influx of GRCs or SEPs back then, so the researchers use proxy data taken from the composition of ancient ice cores dug up at the poles. Nitrates are produced as GRCs react with the atmosphere, so an ice sample containing more nitrates is likely to have been frozen at a time of abundant GRCs. Meanwhile, SEPs are thought to fill ice with rare isotopes of beryllium-10.
Lockwood's group found that in times of low solar activity, there seem to have been more GRCs reaching Earth. This wasn't too surprising: low activity means the solar system's shield—the heliosphere—would have been weaker. The researchers also found that low solar activity seemed to bring fewer SEP events. But to their surprise, there was a caveat: Although fewer, the SEP events appeared to be far more intense. The worst time for SEPs appeared to be at times of "middling" solar activity—precisely the transition period we are thought to be entering. The results were published last month in Geophysical Research Letters..."
Putin Once More Moves to Assume Top Job in Russia
|12:40:18 AM, Tuesday, September 27, 2011|
"MOSCOW — Prime Minister Vladimir V. Putin, who transformed post-Soviet Russia by imposing Kremlin control over most aspects of public life, moved on Saturday to return to the presidency and could remain until 2024, giving him a rule comparable in length with that of Brezhnev or Stalin.
President Dmitri A. Medvedev announced at a party convention in Moscow that he would step aside for Mr. Putin, who served as president from 2000 to 2008 but was limited by the Constitution to two consecutive terms. Mr. Medvedev is to take his place as prime minister after presidential elections in March that Mr. Putin is assured of winning.
At the announcement, wave upon wave of applause washed over the hall, where 11,000 members of Mr. Putin’s party, United Russia, had gathered. Mr. Medvedev’s face was projected on a giant screen above the stage, and he gave a flickering smile as the crowd roared, rose and swung its attention away from him toward Mr. Putin, who was sitting in the audience.
The move brings an end to years of uncertainty, inside and outside Russia, about whether Mr. Putin intended to loosen his grip on power. Neither leader offered any reason for the decision, but Mr. Putin said the deal had been made years ago. If that is true, Mr. Medvedev’s presidency, and the tension that accompanied its end, now looks like an orchestrated political drama that drew in much of the world.
“I want to say directly: An agreement over what to do in the future was reached between us several years ago,” Mr. Putin said. Mr. Medvedev also said there had been no conflict, though his account was less definitive.
“What we are recommending to the convention, it is a deeply thought-out decision,” Mr. Medvedev said. “Moreover, we really discussed this possible turn of events at the time when we formed our comradely union.”
The change casts uncertainty on the future of the so-called reset in relations between the United States and Russia, which benefited from an easy rapport between Mr. Medvedev and President Obama. But a senior Obama administration official played down such concerns on Saturday, saying that American officials “have very deliberately sought to avoid playing favorites.”
“Everyone knows that Putin runs Russia,” the official said, speaking on condition of anonymity. “Remembering this obvious fact means that Putin has supported the reset with the U.S.”
As the news filtered into the street, most Russians expressed little surprise. Mr. Putin’s rise to power accompanied an oil-fueled rise in income, and most Russians feel no nostalgia for the chaotic political pluralism of the 1990s. Opposition to Mr. Putin’s government is growing, however, in places like Moscow, whose residents get information from the Internet and are less dependent on government social payments..."
DMANLT.COM is back!
|11:59:59 PM, Monday, September 26, 2011|
I’m still testing that everything is working correctly, but it would appear we are back in business! Sorry for all the dead links and outdated home page!!! My web host let me down pretty hard this Friday, here is the reply I received from them after trying to update my site and realized everything was reset back to 8/16/2011:
“This morning (9/23/2011) the system experienced a hard drive raid failure. The raid was recovered within 60 minutes of failure. Unfortunately, the raid failure caused some loss of data from the past few weeks. We are recovering our disaster backup from the morning of 9/22/2011 to a secondary location. We will then process a differential comparison of the recovered data and the current live data. This will result in recently created or updated data recovering to your live website. We are unable to recover any file changes / updates that occurred after 9/22/2011 2:00 AM Eastern (GMT-4). We anticipate the file recovery and differential comparison to complete within a 48 hour time frame.”
So, yes, some of the posts are gone, including the ones about the NASA satellite crash and the latest discoveries concerning neutrinos at CERN!!! I might re-post some of them, but I will also just pick up where I left off and start posting new content.
Time to invest in a nice FTP and start scheduling daily back-ups! =/
Scientists Turn Back the Clock on Adult Stem Cells Aging
|1:54:59 AM, Thursday, September 22, 2011|
"Researchers have shown they can reverse the aging process for human adult stem cells, which are responsible for helping old or damaged tissues regenerate. The findings could lead to medical treatments that may repair a host of ailments that occur because of tissue damage as people age. A research group led by the Buck Institute for Research on Aging and the Georgia Institute of Technology conducted the study in cell culture, which appears in the September 1, 2011 edition of the journal Cell Cycle
The regenerative power of tissues and organs declines as we age. The modern day stem cell hypothesis of aging suggests that living organisms are as old as are its tissue specific or adult stem cells. Therefore, an understanding of the molecules and processes that enable human adult stem cells to initiate self-renewal and to divide, proliferate and then differentiate in order to rejuvenate damaged tissue might be the key to regenerative medicine and an eventual cure for many age-related diseases. A research group led by the Buck Institute for Research on Aging in collaboration with the Georgia Institute of Technology, conducted the study that pinpoints what is going wrong with the biological clock underlying the limited division of human adult stem cells as they age.
"We demonstrated that we were able to reverse the process of aging for human adult stem cells by intervening with the activity of non-protein coding RNAs originated from genomic regions once dismissed as non-functional 'genomic junk'," said Victoria Lunyak, associate professor at the Buck Institute for Research on Aging.
Adult stem cells are important because they help keep human tissues healthy by replacing cells that have gotten old or damaged. They're also multipotent, which means that an adult stem cell can grow and replace any number of body cells in the tissue or organ they belong to. However, just as the cells in the liver, or any other organ, can get damaged over time, adult stem cells undergo age-related damage. And when this happens, the body can't replace damaged tissue as well as it once could, leading to a host of diseases and conditions. But if scientists can find a way to keep these adult stem cells young, they could possibly use these cells to repair damaged heart tissue after a heart attack; heal wounds; correct metabolic syndromes; produce insulin for patients with type 1 diabetes; cure arthritis and osteoporosis and regenerate bone.
The team began by hypothesizing that DNA damage in the genome of adult stem cells would look very different from age-related damage occurring in regular body cells. They thought so because body cells are known to experience a shortening of the caps found at the ends of chromosomes, known as telomeres. But adult stem cells are known to maintain their telomeres. Much of the damage in aging is widely thought to be a result of losing telomeres. So there must be different mechanisms at play that are key to explaining how aging occurs in these adult stem cells, they thought.
Researchers used adult stem cells from humans and combined experimental techniques with computational approaches to study the changes in the genome associated with aging. They compared freshly isolated human adult stem cells from young individuals, which can self-renew, to cells from the same individuals that were subjected to prolonged passaging in culture. This accelerated model of adult stem cell aging exhausts the regenerative capacity of the adult stem cells. Researchers looked at the changes in genomic sites that accumulate DNA damage in both groups.
"We found the majority of DNA damage and associated chromatin changes that occurred with adult stem cell aging were due to parts of the genome known as retrotransposons," said King Jordan, associate professor in the School of Biology at Georgia Tech..."
Biologists Discover Genes That Repair Nerves After Injury
|1:32:40 AM, Thursday, September 22, 2011|
"Biologists at the University of California, San Diego have identified more than 70 genes that play a role in regenerating nerves after injury, providing biomedical researchers with a valuable set of genetic leads for use in developing therapies to repair spinal cord injuries and other common kinds of nerve damage such as stroke.
In the September 22 issue of the journal Neuron, the scientists detail their discoveries after an exhaustive two-year investigation of 654 genes suspected to be involved in regulating the growth of axons -- the thread-like extensions of nerve cells that transmit electrical impulses to other nerve cells. From their large-scale genetic screen, the researchers identified 70 genes that promote axon growth after injury and six more genes that repress the re-growth of axons.
"We don't know much about how axons re-grow after they're damaged," said Andrew Chisholm, a professor of biology at UC San Diego. "When you have an injury to your spinal cord or you have a stroke you cause a lot of damage to your axons. And in your brain or spinal cord, regeneration is very inefficient. That's why spinal cord injuries are basically untreatable."
Chisholm and UC San Diego biology professor and HHMI Investigator Yishi Jin headed the collaborative research team, which also included researchers from the University of Oregon.
While scientists in recent decades have gained a good understanding of how nerve cells, or neurons, develop their connections in the developing embryo, much less is known about how adult animals and humans repair -- or fail to repair -- those connections when axons are damaged.
"There are many processes not involved in early development that are involved in switching the neurons to this re-growth mode," said Chisholm. "In essence what we found are genes that people had not suspected previously to be part of this process."
Of particular interest to the UC San Diego biologists are the six genes that appear to repress the growth of axons.
"The discovery of these inhibitors is probably the most exciting finding," said Chisholm, because identifying and eliminating the inhibiting factors to the re-growth of axons could be just as essential as the biochemical pathways that promote axon re-growth in repairing spinal cord injuries and other kinds of nerve damage..."
Dash Berlin - Never Cry Again (Jorn Van Deynhoven Remix)
|1:21:10 AM, Thursday, September 22, 2011|
HOME Older Posts »