http://www.physorg.com/ en-us Physorg.com internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. (PhysOrg.com) -- It`s about as long as the width of a human hair and only half that length across. So it`s tiny - measured in millionths of a meter - and extremely tricky to manipulate. But the meiotic spindle plays so irresistibly important a role in separating our chromosomes during cell division that scientists are compelled to try to study it. http://www.physorg.com/news156015200.html Chemistry Wed, 11 Mar 2009 18:35:13 EST news156015200 (PhysOrg.com) -- Nearly a billion years ago, bacteria evolved an insidious means of infecting their hosts - a syringe-like mechanism able to inject cells with stealthy hijacker molecules. These molecules, called virulence factors, play a sophisticated game of mimicry, imitating many of the cells` normal activities but ultimately co-opting them to serve the bacteria`s needs. Now researchers at The Rockefeller University have identified a new class of these coup artists that appear to take over a key process that regulates a wide range of cellular duties, from cell-cycle progression to cell death, even communication between cells. http://www.physorg.com/news155317992.html Chemistry Tue, 03 Mar 2009 15:54:34 EST news155317992 By altering just one gene in HIV-1, scientists have succeeded in infecting pig-tailed macaque monkeys with a human version of the virus that has until now been impossible to study directly in animals. The new strain of HIV has already been used to demonstrate one method for preventing infection and, with a little tweaking, could be a valuable model for vetting vaccine candidates. http://www.physorg.com/news155238967.html Medicine & Health Mon, 02 Mar 2009 17:56:42 EST news155238967 (PhysOrg.com) -- Stress, the ever-present threat to health and happy living, is tough on the brain. If the strain goes on too long, it can lead to debilitating psychological problems. Part of the reason, according to scientists at The Rockefeller University, may have to do with a little-known family of proteins called kainate receptors that has recently been implicated in major depression. New research in rats may help explain one mechanism by which stress reshapes the brain: namely, by ramping up production of a particular part of these proteins. http://www.physorg.com/news154887406.html Medicine & Health Thu, 26 Feb 2009 16:23:19 EST news154887406 In the real world, odors don't happen one puff at a time. Animals move through, and subsequently distort, plumes of odor molecules that constantly drift, changing direction as the wind disperses them. Now, by exploring how animals smell odors under naturalistic conditions, Rockefeller University scientist Maria Neimark Geffen and her colleagues reveal that the brain encodes these swirling, and complex patterns of molecules using surprisingly little neural machinery. The findings suggest a new theory of how animals smell. http://www.physorg.com/news154787258.html Medicine & Health Wed, 25 Feb 2009 12:28:06 EST news154787258 (PhysOrg.com) -- To measure anxiety in a mouse and suggest it`s similar to anxiety in a person may seem like a stretch, but the metrics sound uncannily familiar. Paralyzed by fear, afraid to leave the house or socialize with others, scared of new places, preferring the dark to the light of day. http://www.physorg.com/news154281616.html Medicine & Health Thu, 19 Feb 2009 16:01:04 EST news154281616 (PhysOrg.com) -- In 1973, Ralph M. Steinman launched a new scientific discipline when he published his discovery of the dendritic cell, an odd-shaped player in the immune system. Since then, dendritic cells have proved to be critical sentinels on the lookout for foreign invaders, involved in early immune responses such as graft rejection, resistance to tumors and autoimmune diseases. Now it appears they need to be considered in research on arterial and heart function, too, according to new experiments to be published February 16 in The Journal of Experimental Medicine. http://www.physorg.com/news154111447.html Medicine & Health Tue, 17 Feb 2009 16:44:42 EST news154111447 For RNA, the gateway to a productive life outside the nucleus is the nuclear pore complex, an amalgamation of 30 kinds of proteins that regulates all traffic passing through the nuclear membrane. New research from Rockefeller University shows that one of these proteins magnetically couples with a special molecule - a helicase - to form a machine that unpacks balled-up messenger RNA particles so that they can be translated. http://www.physorg.com/news153591035.html Biology Wed, 11 Feb 2009 16:11:41 EST news153591035 (PhysOrg.com) -- Most people consider hair as a purely cosmetic part of their lives. To others, it may help uncover one of nature`s best-kept secrets: the body`s ability to regenerate organs. Now, new research from Rockefeller University gets to the root of the problem, revealing that a structure at the base of each strand of hair, the hair follicle, uses a two-step mechanism to activate its stem cells and order them to divide. The mechanism provides insights into how repositories of stem cells may be organized in other body tissues for the purpose of supporting organ regeneration. http://www.physorg.com/news153150734.html Biology Fri, 06 Feb 2009 13:52:48 EST news153150734 (PhysOrg.com) -- A common treatment for attention deficit/hyperactivity disorder, prescribed millions of times a year, may change the brain in the same ways that cocaine does, a new study in mice suggests. Research from Rockefeller University shows that methylphenidate, commonly known as Ritalin, causes physical changes in neurons in reward regions of mouse brains. In some cases, the effects overlapped with those of cocaine. http://www.physorg.com/news152979707.html Medicine & Health Wed, 04 Feb 2009 14:22:33 EST news152979707 During its career, the potentially fatal hepatitis C virus has banked its success on a rather unusual strategy: its limitations. Its inability to infect animals other than humans and chimpanzees has severely hampered scientists in developing a useful small animal model for the disease. But now, in a breakthrough to be published in the January 29 advance online issue of Nature, Rockefeller University scientists have identified a protein that allows the virus to enter mouse cells, a finding that represents the clearest path yet for developing a much-needed vaccine as well as tailored treatments for the 170 million people across the globe living with the tenacious, insidious and rapidly changing virus. http://www.physorg.com/news152386635.html Medicine & Health Wed, 28 Jan 2009 17:37:48 EST news152386635 (PhysOrg.com) -- A new neuroimaging study on stressed-out students suggests that male humans, like male rats, don`t do their most agile thinking under stress. The findings, published this month in the Proceedings of the National Academy of Sciences, show that 20 male M.D. candidates in the middle of preparing for their board exams had a harder time shifting their attention from one task to another than other healthy young men who were not under the gun. http://www.physorg.com/news152292294.html Medicine & Health Tue, 27 Jan 2009 15:25:28 EST news152292294 (PhysOrg.com) -- MicroRNAs - one of the tiniest entities in the human genome - are great escape artists. Despite scientists` best efforts to detect and capture them in different tissues, they often manage to make a getaway, sneaking through the tissues` tiny holes before anyone can detect them. But now, by adapting a time-tested histological technique, Rockefeller University researchers have scored big: They have developed a new method to capture microRNAs before they disappear. The work will help researchers better understand microRNAs` increasingly indisputable role in the onset of disease. http://www.physorg.com/news152205350.html Medicine & Health Mon, 26 Jan 2009 15:16:25 EST news152205350 (PhysOrg.com) -- Distressed swimmers often panic, sapping the strength they need to keep their heads above water until help arrives. When desperate for oxygen, neurons behave in a similar way. They freak out, stupidly discharging energy until they drown in a sea of their own extruded salts. Every year, millions of victims of stroke or brain trauma suffer permanent brain damage because of this mad rush to oblivion that begins once a part of the brain is deprived of blood. http://www.physorg.com/news151342666.html Biology Fri, 16 Jan 2009 15:37:46 EST news151342666 (PhysOrg.com) -- In 1913 Theodore Roosevelt added cartographer to his resume when he and his crew ventured up an unspeakably dangerous and uncharted tributary named the River of Doubt. Now, on a charting expedition of their own, Rockefeller University scientists have completed a journey that has also defied expectation. In work to be published in the January 9 issue of Cell, the team reports the discovery of a new family of receptors in the fly nose, a finding that not only fills in a missing piece in the organizational logic of the insect olfactory system but also unearths one of the most ancient mechanisms that organisms have evolved to smell. http://www.physorg.com/news150640317.html Biology Thu, 08 Jan 2009 12:31:57 EST news150640317 Shredded extracellular matrix (ECM) is toxic to neurons. Chen et al. reveal a new mechanism for how ECM demolition causes brain damage. The study will appear in the December 29, 2008 issue of The Journal of Cell Biology. http://www.physorg.com/news149769426.html Biology Mon, 29 Dec 2008 10:37:06 EST news149769426