http://phys.org/ en-us Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. (PhysOrg.com) -- A research team led by Nancy Speck, PhD, Professor of Cell and Developmental Biology at the University of Pennsylvania School of Medicine, has identified the location and developmental timeline in which a majority of bone marrow stem cells form in the mouse embryo. The findings, appearing online this week in the journal Nature, highlight critical steps in the origin of hematopoietic (or blood) stem cells (HSCs), says senior author Speck, who is also an Investigator with the Abramson Family Cancer Research Institute at Penn. http://phys.org/news150731605.html Biology Fri, 09 Jan 2009 13:53:25 EST news150731605 A new study sheds light on a little understood biological process called quiescence, which enables blood-forming stem cells to exist in a dormant or inactive state in which they are not growing or dividing. According to the study's findings, researchers identified the genetic pathway used to maintain a cell's quiescence, a state that allows bone marrow cells to escape the lethal effects of standard cancer treatments. http://phys.org/news150726406.html Biology Fri, 09 Jan 2009 12:26:46 EST news150726406 Scientists have tricked bone marrow into releasing extra adult stem cells into the bloodstream, a technique that they hope could one day be used to repair heart damage or mend a broken bone, in a new study published today in the journal Cell Stem Cell. http://phys.org/news150645110.html Biology Thu, 08 Jan 2009 13:51:50 EST news150645110 (PhysOrg.com) -- Cellular engineers at the University of Pennsylvania have determined that cardiomyocytes, the specialized cells that form the heart muscle, thrive when cultured in an environment that mimics their own elastic nature but falter, weaken or die when “grown” on stiffer or softer materials. http://phys.org/news150568853.html Biology Wed, 07 Jan 2009 16:40:53 EST news150568853 (PhysOrg.com) -- Stem cells are the body's primal cells, retaining the youthful ability to develop into more specialized types of cells over many cycles of cell division. How do they do it? Scientists at the Carnegie Institution have identified a gene, named scrawny, that appears to be a key factor in keeping a variety of stem cells in their undifferentiated state. Understanding how stem cells maintain their potency has implications both for our knowledge of basic biology and also for medical applications. The results will be published in the January 9, 2009 print edition of Science. http://phys.org/news150557536.html Biology Wed, 07 Jan 2009 13:32:16 EST news150557536 Scientists at the Stanford University School of Medicine and at UC-San Francisco have succeeded in isolating stem cells from human testes. The cells bear a striking resemblance to embryonic stem cells — they can differentiate into each of the three main types of tissues of the body — but the researchers caution against viewing them as one and the same. http://phys.org/news150397024.html Biology Mon, 05 Jan 2009 16:57:04 EST news150397024 One of the current handicaps of cancer treatments is the difficulty of aiming these treatments at destroying malignant cells without killing healthy cells in the process. But a new study by McMaster University researchers has provided insight into how scientists might develop therapies and drugs that more carefully target cancer, while sparing normal healthy cells. http://phys.org/news150383139.html Biology Mon, 05 Jan 2009 13:05:39 EST news150383139 Researchers at the Salk Institute for Biological Studies have developed a versatile mouse model of glioblastoma—the most common and deadly brain cancer in humans—that closely resembles the development and progression of human brain tumors that arise naturally. http://phys.org/news150297782.html Medicine & Health Sun, 04 Jan 2009 13:23:02 EST news150297782 Just after 5 p.m. doors rattle shut and feet begin to shuffle past the narrow lab where Karim Si-Tayeb sits hunched over a microscope, all but invisible to the scientists leaving the Medical College of Wisconsin. Si-Tayeb has already worked eight hours and will work five more, eyes locked on the living cells in his care. Under the microscope, their tiny colonies resemble constellations of tightly packed stars. They carry his ambition. http://phys.org/news150295895.html Biology Sun, 04 Jan 2009 12:51:35 EST news150295895 James Thomson knew that to send a cell back to its past was no trivial matter. Like generations of biologists, the University of Wisconsin-Madison stem cell pioneer had been taught that development was a one-way street; it began with an embryo and finished with all the mature cells that make up the body. Yet in the summer of 2007, Thomson and scientists around the globe were racing to do what once had been thought impossible: to reverse the natural process and return old cells to their embryonic origin. They sought the healing potential of embryonic stem cells - immortal in a lab dish, able to become any cell in the body - but without the controversial destruction of human embryos. http://phys.org/news150098009.html Medicine & Health Fri, 02 Jan 2009 05:53:29 EST news150098009 Scientists at the Hebrew University of Jerusalem have succeeded in reversing brain birth defects in animal models, using stem cells to replace defective brain cells. http://phys.org/news149776804.html Medicine & Health Mon, 29 Dec 2008 12:40:04 EST news149776804 Researchers have what they think may be a basic recipe for capturing and maintaining indefinitely the most fundamental of embryonic stem cells from essentially any mammal, including cows, pigs and even humans. Two new studies reported in the December 26th issue of the journal Cell, a Cell Press publication, show that a cocktail first demonstrated to work in mice earlier this year, which includes inhibitory chemicals, also can be used to successfully isolate embryonic stem cells from rats. http://phys.org/news149345043.html Biology Wed, 24 Dec 2008 12:44:03 EST news149345043 Researchers at the University of Southern California (USC) have, for the first time in history, derived authentic embryonic stem (ES) cells from rats. This breakthrough finding will enable scientists to create far more effective animal models for the study of a range of human diseases. http://phys.org/news149343895.html Biology Wed, 24 Dec 2008 12:24:55 EST news149343895 (PhysOrg.com) -- When neurons started dying in Clive Svendsen's lab dishes, he couldn't have been more pleased.The dying cells – the same type lost in patients with the devastating neurological disease spinal muscular atrophy – confirmed that the University of Wisconsin-Madison stem cell biologist had recreated the hallmarks of a genetic disorder in the lab, using stem cells derived from a patient. By allowing scientists the unparalleled opportunity to watch the course of a disease unfold in a lab dish, the work marks an enormous step forward in being able to study and develop new therapies for genetic diseases. http://phys.org/news149090319.html Medicine & Health Sun, 21 Dec 2008 13:58:39 EST news149090319 Learning how leukemia takes over privileged "niches" within the bone marrow is helping researchers develop treatment strategies that could protect healthy blood-forming stem cells and improve the outcomes of bone marrow transplantation for leukemia and other types of cancer. http://phys.org/news148832246.html Medicine & Health Thu, 18 Dec 2008 14:17:26 EST news148832246 The study, which appears in the December 18 online version of Cell Stem Cell and the January 2009 print edition of the journal, provides proof of principle that alternative sources of stem cells can be created. http://phys.org/news148830455.html Biology Thu, 18 Dec 2008 13:47:35 EST news148830455 Embryonic stem cells could provide a new way of testing drugs for dangerous side effects, according to a leading British researcher. http://phys.org/news148804610.html Medicine & Health Thu, 18 Dec 2008 06:36:50 EST news148804610 Scientists at St. Jude Children's Research Hospital have answered a central question in cancer biology: whether normal stem cells can give rise to tumors. Stem cells are immature cells that can renew themselves and give rise to mature differentiated cells that compose the range of body tissues. In recent years, researchers have developed evidence that cancers may arise from mutant forms of stem cells. http://phys.org/news148745372.html Medicine & Health Wed, 17 Dec 2008 14:09:32 EST news148745372 Researchers at the University of Pennsylvania School of Medicine have discovered stem cells in the esophagus of mice that were able to grow into tissue-like structures and when placed into immune-deficient mice were able to form parts of an esophagus lining. The investigators report their findings online this month in the Journal of Clinical Investigation. http://phys.org/news148578089.html Medicine & Health Mon, 15 Dec 2008 15:41:29 EST news148578089 The first demonstration that a single adult stem cell can self-renew in a mammal was reported at the American Society for Cell Biology (ASCB) 48th Annual Meeting, Dec. 13-17, 2008 in San Francisco. http://phys.org/news148484867.html Biology Sun, 14 Dec 2008 13:47:47 EST news148484867 Up until today scientists assumed that the adult heart is unable to regenerate. Now, researchers and cardiologists from the Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch and the Charité – Universitätsmedizin Berlin (Germany) have been able to show that this dogma no longer holds true. Dr. Laura Zelarayán and Assistant Professor Dr. Martin W. Bergmann were able to show that the body`s own heart muscle stem cells do generate new tissue and improve the pumping function of the heart considerably in an adult organism, when they suppress the activity of a gene regulator known as beta-catenin in the nucleus of the heart cells. http://phys.org/news148228129.html Medicine & Health Thu, 11 Dec 2008 14:28:49 EST news148228129 Like it or not, your living room probably says a lot about you. Given a few uninterrupted moments to poke around, a stranger could probably get a pretty good idea of your likes and dislikes, and maybe even your future plans. Scientists at the Stanford University School of Medicine employing a similar "peeping Tom" tactic to learn more about how stem cells develop have taken a significant step forward by devising a way to recreate the cells' lair — a microenvironment called a niche — in an adult animal. http://phys.org/news148138314.html Biology Wed, 10 Dec 2008 13:31:54 EST news148138314 Taking blood stem cells collected from an umbilical cord into the lab and expanding their number before transplanting them to replace a patient's blood supply is as safe as a standard cord blood transplant, researchers reported today at the 50th Annual Meeting of the American Society of Hematology. http://phys.org/news147975732.html Medicine & Health Mon, 08 Dec 2008 16:22:12 EST news147975732 Typically, tobacco companies market harm-reduction cigarettes as being safer than traditional "full-flavored" brands, leading many smokers to conclude that the use of harm-reduction brands lowers their exposure to toxicants. http://phys.org/news147975441.html Medicine & Health Mon, 08 Dec 2008 16:17:21 EST news147975441 (PhysOrg.com) -- Investigators from Massachusetts General Hospital (MGH) have found a subpopulation of hematopoietic stem cells, the source of all blood and immune system cells, that reproduce much more slowly than previously anticipated. Use of these cells may improve the outcome of stem cell transplants – also called bone marrow transplants – for the treatment of leukemia and other marrow-based diseases. The report will appear in the journal Nature Biotechnology and is being released online to coincide with a similar study in the journal Cell. http://phys.org/news147721045.html Biology Fri, 05 Dec 2008 17:37:25 EST news147721045 The apparent success of a case in which German doctors cured a man of AIDS using a bone marrow transplant comes as no surprise to Gerhard Bauer, a UC Davis stem cell researcher. Bauer has been working for more than 10 years on a similar cure for AIDS based on replacing the devastated immune system of an HIV-infected patient with stem cells that have been engineered to resist human immunodeficiency syndrome. http://phys.org/news147720965.html Medicine & Health Fri, 05 Dec 2008 17:36:05 EST news147720965 Stem cells derived from bone marrow may serve as a novel therapeutic option to treat a disease called epidermolysis bullosa (EB), a disorder characterized by extraordinarily fragile skin, according to a study prepublished online in Blood, the official journal of the American Society of Hematology. http://phys.org/news147618795.html Medicine & Health Thu, 04 Dec 2008 13:13:15 EST news147618795 Many specialized cells, such as in the skin, intestinal mucosa or blood, have a lifespan of only a few days. For these tissues to function, a steady replenishment of specialized cells is indispensable. This is the task of so-called "adult" stem cells also known as tissue stem cells. http://phys.org/news147615685.html Medicine & Health Thu, 04 Dec 2008 12:21:25 EST news147615685 Stem cell researchers at UCLA have proven definitively that blood stem cells are made during mid-gestational embryonic development by endothelial cells, the cells that line the inside of blood vessels. http://phys.org/news147532604.html Medicine & Health Wed, 03 Dec 2008 13:16:44 EST news147532604 (PhysOrg.com) -- One of the most promising new ideas about the causes of cancer, known as the cancer stem-cell model, must be reassessed because it is based largely on evidence from a laboratory test that is surprisingly flawed when applied to some cancers, University of Michigan researchers have concluded. http://phys.org/news147532400.html Medicine & Health Wed, 03 Dec 2008 13:13:20 EST news147532400