http://medicalxpress.com/ en-us Medical Xpress internet news portal provides the latest news on Health and Medicine. (Medical Xpress)—Membrane fusion is a highly regulated event, both inside cells, and between them. From the moment a sperm first fuses with an egg, subsequent developmental events depend upon its proper control. Inside cells, fusion events regulate phagocytosis and vesicle exocytosis, as well as control proliferative and apoptotic events associated with mitochondria. Fusion between cells, as in the formation of placental trophoblasts, osteoclasts, and myoblasts, share many of the genetic and biochemical pathways used for fusion processes occurring inside cells. Developing communities of cells have also improvised, and come up with a few additional tricks of their own. In a paper just published in Nature, researchers from the University of Virginia, have taken a closer look at how myoblasts fuse in the development of skeletal muscle to become multinucleated syncytia. In particular, the researchers reveal how apoptosis in a chosen few of the myotube progenitors is critical to the process. http://medicalxpress.com/news/2013-04-fusion-cell-death-skeletal-muscle.html Medical research Fri, 26 Apr 2013 14:33:32 EST news286205591 (Medical Xpress)—UC San Francisco scientists have discovered that muscle repair requires the action of two types of cells better known for causing inflammation and forming fat. http://medicalxpress.com/news/2013-04-muscle-injury-fat-forming-cells.html Medical research Fri, 19 Apr 2013 07:38:10 EST news285575823 Declining levels of the protein BubR1 occur when both people and animals age, and contribute to cell senescence or deterioration, weight loss, muscle wasting and cataracts. Mayo Clinic researchers have shown that adult progenitor or stem cells—important for repair and regeneration of skeletal muscle and maintenance of healthy fat tissue—are subject to cellular senescence, and that clearance of these cells limits age-related deterioration of these tissues. The findings appear today online in the journal Cell Reports. http://medicalxpress.com/news/2013-04-stem-cell-senescence-aging.html Medical research Thu, 18 Apr 2013 12:42:21 EST news285507734 For years researchers have been trying to identify the molecular changes that occur in tumour-initiating cells from the very first oncogenic mutation to the development of invasive tumors. The most frequently diagnosed skin cancer in humans is basal cell carcinoma, with over a million such cases reported each year. An EU-funded team of researchers led by Prof. Cédric Blanpain of the Université libre de Bruxelles (ULB) has identified the molecular events that occur during basal cell carcinoma initiation. This study was recently published in the journal Nature Cell Biology and it was partially supported by the European Research Council (ERC) Starting Grant worth EUR 1.6 million awarded to Prof. Blanpain. http://medicalxpress.com/news/2012-12-scientists-uncover-cells-basal-cell.html Cancer Fri, 21 Dec 2012 06:36:54 EST news275294208 (Medical Xpress)—Researchers in China have developed a technique for reprogramming cells found in urine into neural progenitor cells that are capable of growing into neurons. In their paper published in Nature Methods, the team describes how they were able to reprogram kidney epithelial cells found in urine into neural progenitor cells that are suitable for use in studying neural diseases. http://medicalxpress.com/news/2012-12-method-reprogramming-cells-urine-neural.html Medical research Mon, 10 Dec 2012 08:30:03 EST news274347931 One of the most outstanding and unresolved questions in cancer biology is the identification of cells at the origin of cancer and the understanding of the molecular changes that occur in tumor initiating cells from the first oncogenic mutation to the development of invasive cancer. Basal cell carcinoma (BCC) is the most frequent cancer in human with more than million of new patients diagnosed each year with BCCs. Recently, the group of Pr. Cédric Blanpain uncovered the cells at the origin of BCC (Youssef et al, Nature Cell Biology, 2010). http://medicalxpress.com/news/2012-11-uncover-molecular-mechanisms-basal-cell.html Cancer Mon, 26 Nov 2012 09:40:01 EST news273144152 (Medical Xpress)—Since stem cells and progenitor cells are regulated by different growth factors, brain tumors arising from these cells might respond differently to different therapies. Researchers at Sanford-Burnham Medical Research Institute found that basic fibroblast growth factor (bFGF) induces stem cell growth, but inhibits neuronal progenitor growth. bFGF also blocks the growth of tumors that originate from progenitors. This study suggests bFGF-like molecules might be used to treat medulloblastoma—but only tumors with the appropriate origins. http://medicalxpress.com/news/2012-11-brain-tumors.html Cancer Tue, 13 Nov 2012 14:53:05 EST news272040578 Within every human kidney, millions of filtration units known as nephrons are hard at work clearing metabolic waste products from the blood. Given the dirty work they perform, one might expect that the cells composing the nephrons undergo routine self-replacement, but nephrons retain very limited regenerative capabilities and essentially shut down when those limits are exceeded—a potential prelude to organ failure. http://medicalxpress.com/news/2012-11-stem-cell-population-day-source.html Medical research Wed, 07 Nov 2012 09:17:03 EST news271502210 Germinal centers are sites in the organs of the lymphatic system, formed during the course of an immune response to infection, where B cells intensely proliferate and modify their DNA in order to produce antibodies specific for the pathogen. However, it is known that the vast majority of lymphomas derive from the B cells at the germinal centers. http://medicalxpress.com/news/2012-09-puzzle-b-cell-lymphoma.html Immunology Sun, 23 Sep 2012 13:00:08 EST news267602068 Researchers at Cold Spring Harbor Laboratory (CSHL) have solved an important piece of one of neuroscience's outstanding puzzles: how progenitor cells in the developing mammalian brain reproduce themselves while also giving birth to neurons that will populate the emerging cerebral cortex, the seat of cognition and executive function in the mature brain. http://medicalxpress.com/news/2012-09-protein-key-fate-decision-cortical.html Neuroscience Fri, 21 Sep 2012 13:05:30 EST news267451518 UCLA stem cell scientists have shown that two common tumor suppressor genes, TSC and PTEN, are vital to regulating the stem cell-like precursor cells that create the blood supply in Drosophila, the common fruit fly. http://medicalxpress.com/news/2012-09-tumor-suppressor-genes-vital-blood.html Medical research Wed, 05 Sep 2012 10:48:54 EST news266060848 The skin, which is an essential barrier that protects our body against the external environment, undergoes constant turnover throughout life to replace dead cells that are constantly sloughed off from the skin surface. During adult life, the number of cells produced must exactly compensate for the number of cells lost. Different theories have been proposed to explain how this delicate balance is achieved. http://medicalxpress.com/news/2012-09-stem-cells-responsible-tissue.html Medical research Tue, 04 Sep 2012 07:41:22 EST news265963274 UCLA researchers have discovered a type of cell that is the "missing link" between bone marrow stem cells and all the cells of the human immune system, a finding that will lead to a greater understanding of how a healthy immune system is produced and how disease can lead to poor immune function. http://medicalxpress.com/news/2012-09-scientists-link-stem-cells-immune.html Immunology Sun, 02 Sep 2012 13:00:23 EST news265786489 As our primary interface with the outside world, the skin needs to be able to protect itself against infectious threats. Specialized cells known as Langerhans cells (LCs) (see image) are an essential component of this defense, helping other immune cells to distinguish friend from foe. "These cells play an important role in maintaining tolerance to cutaneous antigen, while simultaneously promoting immune responses against any invading pathogens," explains Florent Ginhoux at the A*STAR Singapore Immunology Network. http://medicalxpress.com/news/2012-08-langerhans-cells-migrate-destination-multiple.html Medical research Wed, 29 Aug 2012 08:30:01 EST news265446399 The adult human circulatory system contains between 20 and 30 trillion red blood cells (RBCs), the precise size and number of which can vary from person to person. Some people may have fewer, but larger RBCs, while others may have a larger number of smaller RBCs. Although these differences in size and number may seem inconsequential, they raise an important question: Just what controls these characteristics of RBCs? http://medicalxpress.com/news/2012-08-protein-red-blood-cell-size.html Genetics Tue, 28 Aug 2012 18:23:09 EST news265396943 A team at Children's National Medical Center has found that external stimulation has an impact on the postnatal development of a specific region of the brain. Published in Nature Neuroscience, the study used sensory deprivation to look at the growth and collection of NG2-expressing oligodendrocyte progenitor cells (NG2 cells) in the sensory cortex of the brain. This type of research is part of the Center for Neuroscience Research focus on understanding the development and treatment of white matter diseases. http://medicalxpress.com/news/2012-08-external-impacts-white-postnatal-brain.html Medical research Mon, 13 Aug 2012 15:19:21 EST news264089950 A transcription factor called Lyl-1 is necessary for production of the earliest cells that can become T-cells, critical cells born in the thymus that coordinate the immune response to cancer or infections, said a consortium of researchers led by those from Baylor College of Medicine in a report in the journal Nature Immunology. http://medicalxpress.com/news/2012-07-transcription-factor-lyl-critical-early.html Immunology Sun, 08 Jul 2012 13:00:17 EST news260950794 It is well-known that the risks of breast cancer increase dramatically for women over the age of 50, but what takes place at the cellular level to cause this increase has been a mystery. Some answers and the possibility of preventative measures in the future are provided in a new study by researchers at the DOE's Lawrence Berkeley National Laboratory (Berkeley Lab). http://medicalxpress.com/news/2012-06-aging-breast-cancer-uncover-cellular.html Cancer Mon, 04 Jun 2012 11:57:12 EST news258029819 Autologous (self-donated) mononuclear cells derived from bone marrow (BMMNCs) have been found to significantly induce vascular growth when transplanted into patients with diabetes who are suffering from critical limb ischemia caused by peripheral artery disease (PAD), a complication of diabetes. The team of researchers in Seville, Spain who carried out the study published their results in a recent issue of Cell Transplantation (20:10), now freely available on-line. http://medicalxpress.com/news/2012-04-autologous-bone-marrow-derived-mononuclear-cell.html Medical research Wed, 18 Apr 2012 13:14:02 EST news253973634 Researchers at Boston University School of Medicine (BUSM) and Boston Medical Center (BMC) have derived a population of pure lung and thyroid progenitor cells in vitro that successfully mimic the developmental milestones of lung and thyroid tissue formation. The research, which will be published in the April 6 edition of the journal Cell Stem Cell, identifies factors necessary for embryonic stem cells to differentiate into lung progenitor cells and provides key information about how the tissue engineering technology can be used to develop new gene and cell-based therapies to treat lung diseases. http://medicalxpress.com/news/2012-04-derive-purified-lung-thyroid-progenitors.html Medical research Thu, 05 Apr 2012 12:58:56 EST news252849521 New evidence points to a hormone that leaves muscles gobbling up sugar as if they can't get enough. That factor, which can be coaxed out of fat stem cells, could lead to a new treatment to lower blood sugar and improve metabolism, according to a report in the April issue of Cell Metabolism. http://medicalxpress.com/news/2012-04-hormone-lowering-blood-sugar.html Medical research Tue, 03 Apr 2012 12:00:01 EST news252671404 The thymus plays a key role in the body's immune response. It is here where the T lymphocytes or T cells, a major type of immune defence cells, mature. Different types of T cells, designated to perform specific tasks, arise from progenitor cells that migrate to the thymus from the bone marrow. Researchers at the Max Planck Institute of Immunology and Epigenetics in Freiburg have generated artificial thymus tissue in a mouse embryo to enable the maturation of immune cells. In this process, they discovered which signalling molecules control the maturation of T cells. Their results represent the first step towards the production of artificial thymus glands that could be used to replace or augment the damaged organ. http://medicalxpress.com/news/2012-03-artificial-thymus-tissue-enables-maturation.html Immunology Thu, 29 Mar 2012 12:00:07 EST news252239826 A research team led by Nancy Speck, PhD, professor of Cell and Developmental Biology at the Perelman School of Medicine at the University of Pennsylvania, has discovered a molecular marker for the immediate precursors of hematopoietic (blood) stem cells (HSCs) in the developing embryo, which provides much-needed insights for making these cells from engineered precursors. http://medicalxpress.com/news/2011-12-blood-stem-cells.html Medical research Fri, 09 Dec 2011 08:58:52 EST news242643517 Regenerative medicine in spinal cord injuries (SCI) is proving to help the human body create new cell and nerve connections that are severed during this type of injury. In a review of current scientific research for stem cell treatment in SCI published this month in the Springer journal Neurotheraputics, Dr. Michael Fehlings and Dr. Reaz Vawda from the Krembil Neuroscience Centre, Toronto Western Hospital in Ontario, Canada, provide evidence that supports researchers moving beyond the lab to conduct human clinical trials for stem cells. http://medicalxpress.com/news/2011-10-clinical-trials-stem-cell-therapy.html Neuroscience Tue, 18 Oct 2011 11:46:27 EST news238157180 In the latest issue of Nature, researchers at the Perelman School of Medicine at the University of Pennsylvania clarify the role of two proteins key to T-cell development. They found that one well-known protein called Notch passes off much of its role during T-cell maturation to another protein called TCF-1. T cells are required for many aspects of immunity, and understanding how these proteins influence the production of infection-fighting cells could improve treatments for immune-suppressed patients. http://medicalxpress.com/news/2011-08-penn-key-molecule-immune-cell.html Medical research Mon, 08 Aug 2011 13:30:06 EST news232025982 For better or worse, a popular class of anti-diabetic drugs does more than lower blood sugar. One known as rosiglitazone (trade name Avandia) has been in the spotlight for its possible link to increased cardiovascular events, but it also seems to come with unexplained vascular benefits and an unwelcome tendency for weight gain. Now, two separate studies in the July Cell Metabolism, a Cell Press publication, explore those other effects of the drugs known collectively as thiazolidinediones (TZDs), both of which stem from their activity in fat. http://medicalxpress.com/news/2011-07-diabetes-drug-side-effects-fat.html Medical research Tue, 05 Jul 2011 12:29:26 EST news229087751 Neuroepithelial stem cells, the early progenitors for much of the nervous system, need to maintain a keen sense of direction in order to properly manage replication, migration and maturation. These cells are highly polarized, and exclusively initiate cell division at their apical (top) end rather than at their basal (bottom) end, although it has remained a mystery how they determine which way is up. http://medicalxpress.com/news/2011-04-key-nervous-blocking-protein-stem.html Neuroscience Fri, 29 Apr 2011 11:30:02 EST news223294822