Small, artificial blood vessels are meant to offer hope to cardiac-bypass patients. The problem is that these tiny synthetic vessels tend to clog. Now, biomedical engineer Donald Elbert and his team at Washington University, in St. Louis, have developed a new material designed to trick the body into building vessels from its own cells.
Continue reading “A new recipe for artificial blood vessels may help solve a tough clogging problem”
Month: October 2006
Researchers find smallest cellular genome
The smallest collection of genes ever found for a cellular organism comes from tiny symbiotic bacteria that live inside special cells inside a small insect.
The bacteria Carsonella ruddii has the fewest genes of any cell. The bacteria’s newly sequenced genome, the complete set of DNA for the organism, is only one-third the size of the previously reported “smallest” cellular genome.
Continue reading “Researchers find smallest cellular genome”
Technique reveals inner lives of red blood cells
For the first time, researchers at MIT can see every vibration of a cell membrane, using a technique that could one day allow scientists to create three-dimensional images of the inner workings of living cells.
Studying cell membrane dynamics can help scientists gain insight into diseases such as sickle cell anemia, malaria and cancer. Using a technique known as quantitative phase imaging, researchers at MIT’s George R. Harrison Spectroscopy Laboratory can see cell membrane vibrations as tiny as a few tens of nanometers (billionths of a meter).
Continue reading “Technique reveals inner lives of red blood cells”
Immune cell communication key to hunting viruses
Immunologists at the Kimmel Cancer Center at Thomas Jefferson University in Philadelphia have used nanotechnology to create a novel “biosensor” to solve in part a perplexing problem in immunology: how immune system cells called killer T-cells hunt down invading viruses.
They found that surprisingly little virus can turn on the killer T-cells, thanks to some complicated communication among so-called “antigen presenting” proteins that recognize and attach to the virus, in turn, making it visible to the immune system. T-cell receptors then “see” the virus, activating the T-cells.
Continue reading “Immune cell communication key to hunting viruses”
Researchers discover misfolded protein clumps common to dementia, Lou Gehrig’s disease
Scientists have identified a misfolded, or incorrectly formed, protein common to two devastating neurological diseases, frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig’s disease), according to a report in the Oct. 6, 2006, issue of Science. The findings suggest that certain forms of FTD, ALS and possibly other neurological diseases might share a common pathological process.
Continue reading “Researchers discover misfolded protein clumps common to dementia, Lou Gehrig’s disease”
Part Of Human Brain Functions Like A Digital Computer
A region of the human brain that scientists believe is critical to human intellectual abilities surprisingly functions much like a digital computer, according to psychology Professor Randall O’Reilly of the University of Colorado at Boulder.
The finding could help researchers better understand the functioning of human intelligence.
Continue reading “Part Of Human Brain Functions Like A Digital Computer”
Curry may keep elderly minds sharp
A diet containing curry may help protect the aging brain, according a study of elderly Asians in which increased curry consumption was associated with better cognitive performance on standard tests.
Curcumin, found in the curry spice turmeric, possesses potent antioxidant and anti-inflammatory properties.
Continue reading “Curry may keep elderly minds sharp”
A natural chemical found in strawberries boosts memory in healthy mice
Mothers have long exhorted their children to eat their fruit and vegetables. But once kids are beyond mom’s watchful eye, the hated greens often go the way of Barbie dolls and power rangers. Now, there’s another reason to reach for colorful fruits past adolescence.
Fisetin, a naturally occurring flavonoid commonly found in strawberries and other fruits and vegetables, stimulates signaling pathways that enhance long-term memory, report researchers at the Salk Institute for Biological Studies in this week’s Online Early Edition of the Proceedings of the National Academy of Sciences.
Continue reading “A natural chemical found in strawberries boosts memory in healthy mice”
Cancer stem cells linked to radiation resistance
Certain types of brain cancer cells, called cancer stem cells, help brain tumors to buffer themselves against radiation treatment by activating a “repair switch” that enables them to continue to grow unchecked, researchers at Duke University Medical Center have found.
The researchers also identified a method that appears to block the cells’ ability to activate the repair switch following radiation treatment. This finding may lead to the development of therapies for overcoming radiation resistance in brain cancer as well as other types of cancer, the researchers said.
Continue reading “Cancer stem cells linked to radiation resistance”
New study indicates moderate exercise may protect against colds
A moderate exercise program may reduce the incidence of colds. A study published in the November issue of The American Journal of Medicine, led by researchers at Fred Hutchinson Cancer Research Center, found that otherwise sedentary women who engaged in moderate exercise had fewer colds over a one year period than a control group.
Continue reading “New study indicates moderate exercise may protect against colds”
Scientists find gene target that may protect against Crohn’s disease and ulcerative colitis
The discovery by a six-member Inflammatory Bowel Disease (IBD) Genetics Consortium of a genetic risk factor for IBD has been reported in Science Express, the online publication of the journal Science. According to one of the Canadian principal investigators, director of the Laboratory in Genetics and Genomic Medicine of Inflammation at the Montreal Heart Institute, Dr. John D. Rioux, “This discovery may lead to a paradigm shift in our thinking from ‘genetics of diseases to genetics of health’, particularly as concerns Crohn’s Disease and Ulcerative Colitis.”
Continue reading “Scientists find gene target that may protect against Crohn’s disease and ulcerative colitis”
Researchers develop DNA switch to interface living organisms with computers
Researchers at the University of Portsmouth, UK, have developed an electronic switch based on DNA – a world-first bio-nanotechnology breakthrough that provides the foundation for the interface between living organisms and the computer world.
The new technology is called a ‘nanoactuator’ or a molecular dynamo. The device is invisible to the naked eye – about one thousandth of a strand of human hair.
Continue reading “Researchers develop DNA switch to interface living organisms with computers”
A new mechanism of aging discovered
We all age, it’s a fact of life, like death and taxes, and there’s nothing we can do about it. But, how is it possible that of two middle-aged mice, one is already grey, balding and frail? Some mice that age three times faster than normal are revealing to scientists why we grow old.
Researchers have discovered that genetic mutations in the powerhouses of our cells — mitochondria — appear to trigger cells to die and speed up the aging process. Inducing these kinds of mitochondrial mutations leads to premature aging in mice, which live only about half as long as normal mice.
Scientists identify many new neuropeptides in honey bee brains
From humans to honey bees, neuropeptides control brain activity and, hence, our behaviors. Understanding the roles these peptides play in the life of a honey bee will assist researchers in understanding the roles they play in their human counterparts.
There are a million neurons in the brain of a honey bee (Apis mellifera), a brain not much larger than the size of the period at the end of this sentence. The activities of these neurons are influenced by the sea of peptides they are bathed in.
Continue reading “Scientists identify many new neuropeptides in honey bee brains”
Vegetables help fight memory problems in old age
Eating vegetables, not fruit, helps slow down the rate of cognitive change in older adults, according to a study published in the October 24, 2006, issue of Neurology, the scientific journal of the American Academy of Neurology.
Continue reading “Vegetables help fight memory problems in old age”
Killing brain tumors from within: A ‘Trojan horse’ approach
A new method for targeting malignant brain tumors through inducing the cancerous cells to “commit suicide” has been developed by a team of researchers headed by a Hebrew University of Jerusalem professor of biochemistry.
Scientists have pioneered a technique in which a molecule containing long, double-stranded RNA is attached to epidermal growth factor (EGF) and delivered selectively to cells with an abnormally high number of epidermal growth factor receptors (EGFR).
Continue reading “Killing brain tumors from within: A ‘Trojan horse’ approach”
Further evidence that moderate drinking reduces men’s heart attack risk
Even as studies have consistently found an association between moderate alcohol consumption and reduced heart attack risk in men, an important question has persisted: What if the men who drank in moderation were the same individuals who maintained good eating habits, didn’t smoke, exercised and watched their weight? How would you know that their reduced risk of myocardial infarction wasn’t the result of one or more of these other healthy habits?
A new study led by researchers at Beth Israel Deaconess Medical Center (BIDMC) and the Harvard School of Public Health (HSPH) helps answer this question. Reported in the October 23, 2006 issue of the Archives of Internal Medicine, the findings show for the first time that among men with healthy lifestyles, those who consumed moderate amounts of alcohol – defined as between one-half and two drinks daily – had a 40 to 60 percent reduced risk of heart attack compared with healthy men who didn’t drink at all.
Continue reading “Further evidence that moderate drinking reduces men’s heart attack risk”
Stretching bone marrow stem cells pushes them towards becoming blood vessel
When stretched, a type of adult stem cell taken from bone marrow can be nudged towards becoming the type of tissue found in blood vessels, according to a new study by bioengineers at the University of California, Berkeley.
Researchers placed mesenchymal stem cells onto a silicone membrane that was stretched longitudinally once every second. It was a cellular workout routine that helped point the bone marrow stem cell in the direction of becoming the smooth muscle tissue of vascular walls.
Continue reading “Stretching bone marrow stem cells pushes them towards becoming blood vessel”
Grape seed extract halts cell cycle, checking growth of colorectal tumors in mice
Chemicals found in grape seeds significantly inhibited growth of colorectal tumors in both cell cultures and in mice, according to researchers who have already demonstrated the extract’s anti-cancer effects in other tumor types.
Their study, published in the October 18 issue of Clinical Cancer Research, documented a 44 percent reduction of advanced colorectal tumors in the animals, and also revealed, for the first time, the molecular mechanism by which grape seed extract works to inhibit cancer growth. The authors found that it increases availability of a critical protein, Cip1/p21, in tumors that effectively freezes the cell cycle, and often pushes a cancer cell to self destruct.
Continue reading “Grape seed extract halts cell cycle, checking growth of colorectal tumors in mice”
Molecular mechanism provides intra-cellular traffic signal
City planners could learn a lesson or two from tiny cells on how to maximize traffic flow.
Researchers at the University of Illinois at Chicago have found that intra-cellular trafficking is tightly coordinated for maximum flow through cellular compartments — much as vehicles on a crowded road are allowed to pass quickly through a succession of green traffic lights.
Continue reading “Molecular mechanism provides intra-cellular traffic signal”
Popular anti-aging supplement has no beneficial effects, study finds
A widely used antiaging supplement has no effect on aging markers such as muscle strength, peak endurance, muscle mass, fat mass and glucose tolerance in elderly men and women, according to Mayo Clinic researchers. The findings from their two-year study appear in the Oct. 19 issue of the New England Journal of Medicine.
The findings serve to dispel the belief that dehydroepiandrosterone (DHEA), sold extensively as an antiaging supplement in health and grocery stores, can reverse age-related alterations in body composition and function, says the study’s lead author K. Sreekumaran Nair, M.D., Mayo Clinic endocrinologist.
Continue reading “Popular anti-aging supplement has no beneficial effects, study finds”
Genetic repair mechanism clears the way for sealing DNA breaks
Scientists investigating an important DNA-repair enzyme now have a better picture of the final steps of a process that glues together, or ligates, the ends of DNA strands to restore the double helix.
Continue reading “Genetic repair mechanism clears the way for sealing DNA breaks”
Research team identifies human ‘memory gene’
Researchers at the Translational Genomics Research Institute (TGen) today announced the discovery of a gene that plays a significant role in memory performance in humans. The findings, reported by TGen and research colleagues at the University of Zurich in Switzerland, Banner Alzheimer’s Institute, and Mayo Clinic Scottsdale, appear in the October 20 issue of Science. The study details how researchers associated memory performance with a gene called Kibra in over 1,000 individuals –both young and old– from Switzerland and Arizona. This study is the first to describe scanning the human genetic blueprint at over 500,000 positions to identify cognitive differences between humans.
Continue reading “Research team identifies human ‘memory gene’”
Scientists prove that parts of cell nuclei are not arranged at random
The nucleus of a mammal cell is made up of component parts arranged in a pattern which can be predicted statistically, says new research published today. Scientists hope this discovery that parts of the inside of a cell nucleus are not arranged at random will give greater insight into how cells work and could eventually lead to a greater understanding of how they become dysfunctional in diseases like cancer.
Continue reading “Scientists prove that parts of cell nuclei are not arranged at random”
Two miles underground, strange bacteria are found thriving
A Princeton-led research group has discovered an isolated community of bacteria nearly two miles underground that derives all of its energy from the decay of radioactive rocks rather than from sunlight. According to members of the team, the finding suggests life might exist in similarly extreme conditions even on other worlds.
Continue reading “Two miles underground, strange bacteria are found thriving”
Researchers discover a protein as potential tactic to prevent tumors
Mayo Clinic researchers have found that a protein that initiates a “quality control check” during cell division also directs cell death for those cells damaged during duplication. This knowledge represents a potential “bulls eye” for targeting anti-tumor drugs. The findings appear in the current issue of Science.
Continue reading “Researchers discover a protein as potential tactic to prevent tumors”
Scientists provide insights into how the immune system avoids attacking itself
finding by University of Pennsylvania School of Medicine researchers about how immune cells “decide” to become active or inactive may have applications in fighting cancerous tumors, autoimmune diseases, and organ transplant rejection. Pathology and Laboratory Medicine Professor Gary A. Koretzky, MD, PhD, director of the Signal Transduction Program at Penn’s Abramson Family Cancer Research Institute describes, in the current issue of Nature Immunology, one way in which T cells may develop tolerance to host cells and proteins. Koretzky and colleagues found that small fatty acids called diacylglycerols (DAGs), and the enzymes that metabolize them, are critical players in the molecular pathway that leads to activity versus inactivity.
Continue reading “Scientists provide insights into how the immune system avoids attacking itself”
Researchers make nanosheets that mimic protein formation
How to direct and control the self-assembly of nanoparticles is a fundamental question in nanotechnology.
University of Michigan researchers have discovered a way to make nanocrystals in a fluid assemble into free-floating sheets the same way some protein structures form in living organisms.
Continue reading “Researchers make nanosheets that mimic protein formation”
Researchers discover mechanism that determines when detailed memories are retained
The levels of a chemical released by the brain determine how detailed a memory will later be, according to researchers at UC Irvine.
The neurotransmitter acetylcholine, a brain chemical already established as being crucial for learning and memory, appears to be the key to adding details to a memory. In a study with rats, Norman Weinberger, research professor of neurobiology and behavior, and colleagues determined that a higher level of acetylcholine during a learning task correlated with more details of the experience being remembered. The results are the first to tie levels of acetylcholine to memory specificity and could have implications in the study and treatment of memory-related disorders.
Continue reading “Researchers discover mechanism that determines when detailed memories are retained”
Coolest biological cartoon ever!
This movie from Harvard shows the inner life of a cell with an inspring music. This is arguably the coolest biological cartoon I have ever seen. It so beautifully captures the essence of a biological system. Thanks to my friend Dr. Chris Arendt for forwarding this link.
Do Dieting Monkeys Live Healthier and Longer Lives?
An ongoing study at the University of Wisconsin-Madison in which rhesus monkeys are being fed an extremely calorie-restricted diet gives preliminary evidence that the regime prevents age-related diseases. For decades, scientists have known that a diet of about 30-percent fewer calories than normal extends the lifespan of mice by 10 to 20 percent, reduces their incidence of cancer, and prevents the deterioration of learning and memory in the rodents. And similar effects have been shown in lower organisms from yeast to fruit flies. But such life extension has not been proven yet in primates. Preliminary evidence from one of the largest studies of calorie-restricted diet in primates shows health benefits.
Read the rest of the story at MIT Technology Review journal
Antibiotic inhibits cancer gene activity
A little-known antibiotic shows early promise as an anti-cancer agent, inhibiting a gene found at higher-than-normal levels in most human tumors, according to researchers at the University of Illinois at Chicago College of Medicine.
Continue reading “Antibiotic inhibits cancer gene activity”