Archive for March 2009
Harvard University scientists are a step closer to creating synthetic forms of life, part of a drive to design man-made organisms that may one day be used to help produce new fuels and create biotechnology drugs.
Researchers led by George Church, whose findings helped spur the U.S. human genome project in the 1980s, have copied the part of a living cell that makes proteins, the building blocks of life. The finding overcomes a major roadblock in making synthetic self-replicating organisms, Church said today in a lecture at Harvard in Cambridge, Massachusetts.
The technology can be used to program cells to make virtually any protein, even some that don’t exist in nature, the scientists said. That may allow production of helpful new drugs, chemicals and organisms, including living bacteria. It also opens the door to ethical concerns about creation of processes that may be uncontrollable by life’s natural defenses.
–>>>>>>> Article in Bloomberg news
Posted March 10, 2009on:
Chronic stress takes a physical and emotional toll on our bodies and scientists are working on piecing together a medical puzzle to understand how we respond to stress at the cellular level in the brain. Being able to quickly and successfully respond to stress is essential for survival.
Using a rat model, Jaideep Bains, PhD, a University of Calgary scientist and his team of researchers at the Hotchkiss Brain Institute have discovered that neurons in the hypothalamus, the brain’s command centre for stress responses, interpret ‘off’ chemical signals as ‘on’ chemical signals when stress is perceived. “It’s as if the brakes in your car are now acting to speed up the vehicle, rather than slow it down.” says Bains. This unexpected finding is being published in the March 1st online edition of Nature Neuroscience. Read the rest of this entry »
With obesity reaching epidemic levels, researchers at the Ohio State University Medical Center are studying a potentially long-term treatment that involves injecting a gene directly into one of the critical feeding and weight control centers of the brain. Read the rest of this entry »
A strange and confused chapter in the history of American medical research ended Monday morning, when President Obama signed an executive order ending a ban on federal funding for embryonic-stem-cell lines that were developed after August 9, 2001.
The ban has been roundly denounced as hypocritical and destructive, stunting advances in one of the most exciting fields of medical research. Some restrictions will still apply, and whether research will provide much-anticipated cures is an open question — but at least the question will be answered by science, with the government’s full weight behind it.
–>>>>>>>> Article in Wired
The function of a protein is determined both by its structure and by its interaction partners in the cell. Until now, proteins had to be isolated for analyzing them. An international team of researchers from Tokyo Metropolitan University, Goethe University, and the Frankfurt Institute for Advanced Studies (FIAS) has, for the first time, determined the structure of a protein in its natural environment, the living cell. Using nuclear magnetic resonance (NMR) spectroscopy, the researchers solved the structure of a protein within the bacterium Escherichia coli. “We have reached an important goal of molecular biology”, says Prof. Peter Güntert from the Goethe University’s Biomolecular Magnetic Resonance Center. (BMRZ)
More and more information is being gathered about how human genes influence medically relevant traits, such as the propensity to develop a certain disease. The ultimate goal is to predict whether or not a given trait will develop later in life from the genome sequence alone (i.e. from the sequence of the bases that make up the DNA strands that store genetic information in every cell of the body).
Now, writing in the journal Current Biology, a Cell Press publication, a group of researchers form the Netherlands put this goal to a test using eye colour. The group around Manfred Kayser of the Erasmus University Medical Center Rotterdam showed that it can be predicted with an accuracy of over 90% whether a person has blue or brown eyes by analysing DNA from only 6 different positions of the genome. Read the rest of this entry »
Posted March 9, 2009on:
Chemicals present in cranberries—and not the acidity of cranberry juice, as previously thought—prevent infection-causing bacteria from attaching to the cells that line the urinary tract, as documented in a report published in Journal of Medicinal Food, a peer-reviewed journal published by Mary Ann Liebert, Inc. Read the rest of this entry »
The theory that a higher metabolism means a shorter lifespan may have reached the end of its own life, thanks to a study published in the journal Physiological and Biochemical Zoology. The study, led by Lobke Vaanholt (University of Groningen, The Netherlands), found that mice with increased metabolism live just as long as those with slower metabolic rates. Read the rest of this entry »
Posted March 9, 2009on:
An experimental procedure that dramatically strengthens stem cells’ ability to regenerate damaged tissue could offer new hope to sufferers of muscle-wasting diseases such as myopathy and muscular dystrophy, according to researchers from the University of New South Wales (UNSW).
The world-first procedure has been successfully used to regrow muscles in a mouse model, but it could be applied to all tissue-based illnesses in humans such as in the liver, pancreas or brain, the researchers say. Read the rest of this entry »
Posted March 8, 2009on:
In the March, 2009 issue of Clinical Immunology, researchers from the David Geffen School of Medicine at the University of California, Los Angeles and the U.S. Environmental Protection Agency report that sulforaphane, a compound that occurs in cruciferous vegetables such as broccoli, may help protect against respiratory inflammation and the diseases it causes, including asthma, chronic obstructive pulmonary disease, and allergic rhinitis. Read the rest of this entry »
EXACT replicas of a man’s thumb bones have been made for the first time using a 3D printer. The breakthrough paves the way for surgeons to replace damaged or diseased bones with identical copies built from the patients’ own cells.
“In theory, you could do any bone,” says Christian Weinand of the Insel Hospital in Berne, Switzerland, head of the team that copied his thumb bones. “Now I can put spares in my pocket if I want,” he says.
—->>>>>>> Article in New Scientist
Researchers have found the factor that makes the difference between a stem cell in the intestine and any other cell. The discovery reported in the March 6th issue of the journal Cell, a Cell Press publication, is an essential step toward understanding the biology of the stem cells, which are responsible for replenishing all other cells in the most rapidly self-renewing tissue in mammals. It may also have implications for colon cancer, according to the researchers.
The report finds evidence that a transcription factor called Achaete scute-like 2 (Ascl2) switches on the stem cell program in intestinal cells. Transcription factors are genes that control other genes. Read the rest of this entry »
Scientists say they have discovered a way to stop cancer spreading to other parts of the body.
Cancer metastasis, where the cancer spreads from its original location, is known to be responsible for 90% of cancer-related deaths.
Institute of Cancer Research scientists have found that an enzyme called LOX is crucial in promoting metastasis, Cancer Cell journal reports.
—>>>>>> Article in BBC News
Posted March 8, 2009on:
Deploying a method that removes potentially cancer-causing genes, Whitehead Institute researchers have “reprogrammed” human skin cells from Parkinson’s disease patients into an embryonic-stem-cell-like state. Whitehead scientists then used these so-called induced pluripotent stem (iPS) cells to create dopamine-producing neurons, the cell type that degenerates in Parkinson’s disease patients.
This marks first time researchers have generated human iPS cells, successfully removed the potentially problematic reprogramming genes, and seen the cells maintain their embryonic stem-cell-like state. Previous methods to reprogram mature cells into iPS cells inserted cancer-causing genes into the cells’ DNA. Because the current method removes the cancer-causing genes, the resulting iPS cells’ DNA is virtually identical to the DNA of the original adult cells. These iPS cells can be matured into any cell type, allowing for screens of potential drug therapies and study of patient-specific disease at the cellular level. Read the rest of this entry »
Posted March 8, 2009on:
Scientists at the Sol Goldman Pancreatic Cancer Research Center at the Johns Hopkins Kimmel Cancer Center have used “personalized genome” sequencing on an individual with a hereditary form of pancreatic cancer to locate a mutation in a gene called PALB2 that is responsible for initiating the disease. The discovery marks their first use of a genome scanning system to uncover suspect mutations in normal inherited genes. Read the rest of this entry »
Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory can now control how cells connect with one another in vitro and assemble themselves into three-dimensional, multicellular microtissues. The researchers demonstrated their method by constructing a tailor-made artificial cell-signaling system, analogous to natural cell systems that communicate via growth factors.
We know that lifespan can be extended in animals by restricting calories such as sugar intake. Now, according to a study published in the journal PLoS Genetics, Université de Montréal scientists have discovered that it’s not sugar itself that is important in this process but the ability of cells to sense its presence.
Aging is a complex phenomenon and the mechanisms underlying aging are yet to be explained. What researchers do know is that there is a clear relationship between aging and calorie intake. For example, mice fed with half the calories they usually eat can live 40 percent longer. How does this work?
As part of the PLoS Genetics study, Université de Montréal Biochemistry Professor Luis Rokeach and his student Antoine Roux discovered to their surprise that if they removed the gene for a glucose sensor from yeast cells, they lived just as long as those living on a glucose-restricted diet. In short, the fate of these cells doesn’t depend on what they eat but what they think they’re eating. Read the rest of this entry »
In addition to providing a simple and much less expensive means of making artemisinin, the most powerful anti-malaria drug in use today, synthetic biology can also help to extend the effectiveness of this drug. Fermenting artemisinin via engineered microbes, such as yeast, can be done at far lower costs than extracting the drug from Artemsisia annua, the sweet wormwood tree, making microbial-based artemisinin a much cheaper but equally effective treatment. Restricting access to this technology to responsible manufacturers who will bundle artemisinin as part of an anti-malarial drug “cocktail” rather than selling it as a monotherapy should delay or even prevent malaria parasites from developing resistance. Recently, there have been reports of malaria parasites in West Africa showing some signs of resistance to artemisinin.
Posted March 8, 2009on:
Researchers at the University of Pennsylvania School of Veterinary Medicine and Pennsylvania State University have identified for the first time a specific “niche factor” in the mouse testes called colony stimulating factor 1, Csf1, that has a direct effect on sperm stem cell self-renewal. Moreover, the study shows that the origin of this growth factor is the Leydig cell — located in the testes and stimulated by the pituitary gland to supply testosterone — that secretes Csf1 and enhances self-renewal of the stem cells. Read the rest of this entry »
A team of scientists at the Scripps Research Institute has found a way to use specially programmed chemicals to elicit an immediate immune response in laboratory animals against two types of cancer. The experiments, thus far performed only in mice, appear to overcome a major drawback of vaccinations—the lag time of days, or even weeks, that it normally takes for immunity to build against a pathogen. This new method of vaccination could potentially be used to provide instantaneous protection against diseases caused by viruses and bacteria, cancers, and even virulent toxins. Read the rest of this entry »
Stem cells can thrive in segments of well-vascularized tissue temporarily removed from laboratory animals, say researchers at the Stanford University School of Medicine. Once the cells have nestled into the tissue’s nooks and crannies, the so-called “bioscaffold” can then be seamlessly reconnected to the animal’s circulatory system.
The new technique neatly sidesteps a fundamental stumbling block in tissue engineering: the inability to generate solid organs from stem cells in the absence of a reliable supply of blood to the interior of the developing structure. Read the rest of this entry »
Mayo Clinic researchers found that healthy, older adults who participated in a computer-based training program to improve the speed and accuracy of brain processing showed twice the improvement in certain aspects of memory, compared to a control group. Read the rest of this entry »
In the latest clinical trial for a technique to detect pancreatic cancer, researchers found they could differentiate cells that are cancerous from those that are benign, pre-cancerous, or even early stage indicators called mucinous cystic lesions.