 |
|
International research team seeks to unravel flatworm regeneration
July 21, 2009Planarian flatworms are only a few millimeters up to a few centimeters in length, live in freshwater and are the object of intense research, because they possess the extraordinary ability to regenerate lost tissue with the help of their stem cells (neoblasts) and even grow an entirely new worm out of minute amputated body parts. Now researchers from the Max Delbrück Center in Berlin, Germany together with researchers in the US and Canada present the first comprehensive catalogue of small RNAs of planaria, elements that regulate gene expression. They also have identified small RNAs which may play a role in regeneration and stem cell function, Nikolaus Rajewsky from the MDC points out (PNAS, Early Edition)*.
Research suggests that the regeneration of the flatworm involves hundreds of genes. But how are these genes regulated? With the latest technologies researchers search for molecules which regulate genes, such as the small RNAs and especially microRNAs (miRNAs).
Of the hundreds of known planarian species the team of researchers from Germany, the US and Canada chose Schmidtea mediterranea. Full 30 percent of the cells of this species consists of stem cells, making it a unique model system to investigate the function of stem cells.
Many planaria genes resemble those of humans, and also many genes specifically linked to planarian stem cell biology and regeneration are conserved in humans. Understanding planarian regeneration therefore promises to yield important insights into human regeneration and stem cell biology, the researchers are convinced.
The researchers looked for small RNAs in stem cells as well as in the whole planarian organism. They discovered 60 new microRNA genes and could demonstrate that ten microRNAs are specifically linked to stem cell biology and may therefore play a role in regeneration. A few of these microRNAs also exist in humans.
Furthermore, the researchers discovered millions of piRNAs. This is a group of just recently discovered small RNA molecules which are important for the stability of the genome. The researchers could demonstrate that piRNAs are highly represented in the planarian stem cells and likely function in a similar way as in mammals.
Because stem cells are potentially immortal, they need to strictly control their genome integrity during transmission to future generations, and particulary to protect it against the uncontrolled propagation of mobile genetic elements, transposons. PiRNAs have been shown to selectively silence transposons in the fly and mouse genomes. Due to their analysis the researchers assume that piRNAs have a similar function in the planarian stem cells. Further studies are needed to investigate this.
Helmholtz Association of German Research Centres
Many planaria genes resemble those of humans, and also many genes specifically linked to planarian stem cell biology and regeneration are conserved in humans. Understanding planarian regeneration therefore promises to yield important insights into human regeneration and stem cell biology, the researchers are convinced.
The researchers looked for small RNAs in stem cells as well as in the whole planarian organism. They discovered 60 new microRNA genes and could demonstrate that ten microRNAs are specifically linked to stem cell biology and may therefore play a role in regeneration. A few of these microRNAs also exist in humans.
Furthermore, the researchers discovered millions of piRNAs. This is a group of just recently discovered small RNA molecules which are important for the stability of the genome. The researchers could demonstrate that piRNAs are highly represented in the planarian stem cells and likely function in a similar way as in mammals.
Because stem cells are potentially immortal, they need to strictly control their genome integrity during transmission to future generations, and particulary to protect it against the uncontrolled propagation of mobile genetic elements, transposons. PiRNAs have been shown to selectively silence transposons in the fly and mouse genomes. Due to their analysis the researchers assume that piRNAs have a similar function in the planarian stem cells. Further studies are needed to investigate this.
Helmholtz Association of German Research Centres
Stem Cells Current Events and Stem Cells News RSSNew discovery about the formation of new brain cells
The generation of new nerve cells in the brain is regulated by a peptide known as C3a, which directly affects the stem cells' maturation into nerve cells and is also important for the migration of new nerve cells through the brain tissue, reveals new research from the Sahlgrenska Academy published in the journal Stem Cells.
Umbilical cord blood stem cell transplant may help lung, heart disorders
Two separate studies published in the current issue of Cell Transplantation (18:8), - now freely available on-line have shown that transplanted human-derived umbilical cord blood (UCB) stem cells transplanted in an animal model had positive therapeutic effects on specific lung and heart disorders the animal models.
Gene mismatch influences success of bone marrow transplants
A commonly inherited gene deletion can increase the likelihood of immune complications following bone marrow transplantation, an international team of researchers reports in the November 22 advance online issue of Nature Genetics.
New research shows versatility of amniotic fluid stem cells
For the first time, scientists have demonstrated that stem cells found in amniotic fluid meet an important test of potential to become specialized cell types, which suggests they may be useful for treating a wider array of diseases and conditions than scientists originally thought.
First reconstitution of an epidermis from human embryonic stem cells
Stem cell research is making great strides. This is yet again illustrated by a study carried out by the I-STEM* Institute (I-STEM/ Inserm UEVE U861/AFM), published in the Lancet on 21 November 2009. The I-STEM team, directed by Marc Peschanski has just succeeded in recreating a whole epidermis from human embryonic stem cells.
Bone Implant Offers Hope for Skull Deformities
A synthetic bone matrix offers hope for babies born with craniosynostosis, a condition that causes the plates in the skull to fuse too soon.
Your Own Stem Cells Can Treat Heart Disease
The largest national stem cell study for heart disease showed the first evidence that transplanting a potent form of adult stem cells into the heart muscle of subjects with severe angina results in less pain and an improved ability to walk. The transplant subjects also experienced fewer deaths than those who didn't receive stem cells.
Is hepatic differentiation of embryonic stem cells induced by valproic acid and cytokines?
Embryonic stem (ES) cells, known for their capacity to proliferate indefinitely and differentiate into almost all types of cells including hepatocytes, have raised the hope of cellular replacement therapy for liver failure.
Paradoxical protein might prevent cancer
One difficulty with fighting cancer cells is that they are similar in many respects to the body's stem cells. By focusing on the differences, researchers at Karolinska Institutet have found a new way of tackling colon cancer. The study is presented in the prestigious journal Cell.
U of M researchers find 2 units of umbilical cord blood reduce risk of leukemia recurrence
A new study from the Masonic Cancer Center, University of Minnesota shows that patients who have acute leukemia and are transplanted with two units of umbilical cord blood (UCB) have significantly reduced risk of the disease returning.
More Stem Cells Current Events and Stem Cells News Articles
 |
Essentials of Stem Cell Biology, Second Edition by Robert Lanza (Editor), John Gearhart (Editor), Brigid Hogan (Editor), Douglas Melton (Editor), Roger Pederson (Editor), E. Donnall Thomas (Editor), James Thomson (Editor), Sir Ian Wilmut (Editor) First developed as an accessible abridgement of the successful Handbook of Stem Cells, Essentials of Stem Cell Biology serves the needs of the evolving population of scientists, researchers, practitioners and students that are embracing the latest advances in stem cells. Representing the combined effort of seven editors and more than 200 scholars and scientists whose pioneering work has defined our understanding of stem cells, this book combines the prerequisites for a general understanding of adult and embryonic stem cells with a presentation by the world?s experts of the latest research information about specific organ systems. From basic biology/mechanisms, early development, ectoderm, mesoderm, endoderm, methods to application of stem cells to specific human diseases, regulation and... |
 |
Stem Cell Now by Christopher Thomas Scott (Author) The essential account of the most important scientific advance—and most volatile ethical debate—of our time While many believe stem cell research holds the key to curing a wide range of ailments, others see this research as opening a Pandora’s box that will devalue human life. In Stem Cell Now, Christopher Scott—executive director of Stanford University’s Stem Cells and Society Program—lays out the scientific and ethical issues surrounding this national dilemma. Scott guides readers through the latest advances in stem cell research in clear, accessible language, telling the stories of the researchers who are exploring the potential of stem cells to cure cancer, grow new organs, and repair the immune system. He also leads readers through a... |
 |
The Stem Cell Divide: The Facts, the Fiction, and the Fear Driving the Greatest Scientific, Political, and Religious Debate of Our Time by Michael Bellomo (Author) There has been much recent debate about the merits, dangers, and nature of stem cell research. Some see in it the answer to every debilitating disease known to man, while others see it as a step away from human cloning. While the battle has raged, research is moving ahead, and California has already passed a measure that will give $3 billion in support to stem cell research. But as politics, religion, and the media weigh in on this complex issue, more and more of the scientific reality of stem cell research is getting lost. In the search for the truth about stem cell science, the author has interviewed the scientists whose cutting-edge research is at the very heart of this hot-button issue. The book explains what they have accomplished so far, what they're currently doing, and what... |
 |
Human Stem Cell Manual: A Laboratory Guide by Jeanne F. Loring (Editor), Robin L. Wesselschmidt (Editor), Philip H. Schwartz (Editor) Stem cells are self-replicating and undifferentiated, meaning their function is not yet cell, tissue, or organ-specific. Due to the unique nature of these cells, research into their biology and function holds great promise for therapeutic applications through replacement or repair of diseased and damaged cells. This reader-friendly manual provides a practical "hands on" guide to the culture of human embryonic and somatic stem cells. By presenting methods for embryonic and adult lines side-by-side, the authors lay out an elegant and unique path to understanding the science of stem cell practice. The authors begin with a broad-based introduction to the field, and also review legal and regulatory issues and patents. Each experimental strategy is presented with an historical introduction,... |
 |
Stem Cell Research: Medical Applications And Ethical Controversy (The New Biology) by Joseph, Ph.D. Panno (Author) This is an informative reference to the technological advances, applications, and issues of stem cell research. The past few years have seen controversy and debate surrounding stem cell research. Because skin cells have the capability to divide - unlike most of the cells in our body - our skin can heal itself through the division of cells. Scientists have attempted to apply this concept to major organs, trying to see if stem cells can be used to make the repairs that post-mitotic cells cannot. "Stem Cell Research" is a comprehensive and interesting introduction to this popular new science for non-experts. Explaining how stems cells can be obtained from several places, including skin, bone marrow, and most usefully, embryos, this book covers all the fundamental aspects of stem cell... |
 |
Cell of Cells: The Global Race to Capture and Control the Stem Cell by Cynthia Fox (Author) Publication Date is March 26, 2007 |
 |
The Stem Cell Dilemma: Beacons of Hope or Harbingers of Doom? by Leo Furcht (Author), William Hoffman (Author) TodayÕs scientists are showing us how stem cells create and repair the human body. Unlocking these secrets has become the new Holy Grail of biomedical research. But behind that search lies a sharp divide. Stem cells offer the hope of creating or repairing tissues lost to age, disease, and injury. Yet because of this ability, stem cells hold the potential to incite an international biological arms race. THE STEM CELL DILEMMA will tell you everything you ever wanted to know about stem cells: what they are, how they work, and why their use has become so controversial. We are standing at a scientific crossroads, the likes of which the world has never seen. It is a moment that will change forever the practice of medicine and the future of life as we know it. |
 |
LIFE EXTENSION, SKIN STEM CELL SERUM 1 OZ by Life Extension Skin Stem Cell Serum (Nutraceautical) has been specifically formulated to allow plant stem cells to preserve and protect skin stem cells. The Skin Stem Cell Serum (Mallus Domestica) is a liposomal preparation based on the stem cells of a rare Swiss apple. |
 |
Mesenchymal Stem Cells: Methods and Protocols (Methods in Molecular Biology) by Darwin J. Prockop (Editor), Donald G. Phinney (Editor), Bruce A. Bunnell (Editor) For over forty years, mesenchymal stem cells (MSCs) have been scrutinized and studied, garnering much attention due to their broad therapeutic efficacy. In Mesenchymal Stem Cells: Methods and Protocols, leaders in the field were assembled to contribute detailed methodologies for the isolation and characterization of human and rodent MSCs. Recently, these vital cells have shown therapeutic benefits in the treatment of myocardial infarction, stroke, lung diseases, spinal cord injury and other neurological disorders, thus promising a boundless future in their study. Cutting edge and easy to use, Mesenchymal Stem Cells: Methods and Protocols is the perfect resource for scientists attempting to pursue this important and ever-developing field of research. |
 |
Stem Cell Wars: Inside Stories from the Frontlines by Eve Herold (Author), George Daley Dr. (Foreword) Americans have become the victims of misinformation about stem cell research. Over the last few years, the stem cell debate has been intensely political, religious, and confusing to many people. Now, Eve Herold explains what this science is all about, who is for and against it, and why it must go forward. She pulls together fascinating stories to highlight every aspect of this multifaceted field. She exposes the politics of stem cell research and demonstrates how the outcome of the debate could ultimately affect all of us. Packed with real-life stories of the people caught up in this groundbreaking struggle, Stem Cell Wars cuts through the noise and sets the standard for future debate. |
| © 2009 BrightSurf.com |