Archive for August 2009
Low-carb slimming diets may clog arteries and increase the risk of heart attacks and strokes, a study suggests.
Diets based on eating lots of meat, fish and cheese, while restricting carbohydrates have grown in popularity in recent years.
But the Beth Israel Deaconess Medical Center in the US found such habits caused artery damage in tests on mice.
Scientists have developed a new molecular sensor that can reveal the amount of zinc in cells, which could tell us more about a number of diseases, including type 2 diabetes. The research, published today in Nature Methods, opens the door to the hidden world of zinc biology by giving scientists an accurate way of measuring the concentration of zinc and its location in cells for the first time. Read the rest of this entry »
Posted August 31, 2009on:
In a finding that sheds new light on the neural mechanisms involved in social behavior, neuroscientists at the California Institute of Technology (Caltech) have pinpointed the brain structure responsible for our sense of personal space.
The discovery, described in the August 30 issue of the journal Nature Neuroscience, could offer insight into autism and other disorders where social distance is an issue.
A new method tested in monkeys for replacing mitochondrial DNA could one day prevent devastating diseases.
Posted August 25, 2009on:
The American Heart Association today released new recommendations on limiting intake of added dietary sugars.
Back in 2006, the American Heart Association (AHA) recommended minimizing consumption of beverages and foods with added sugars.
Now, the AHA is getting more specific, with recommendations detailed down to the teaspoon based on a person’s age, sex, and activity level.
Researchers have found a genetic link between physical pain and social rejection, which means that breaking up with a partner really can be painful.
Psychologists at the University of California, Los Angeles say the human body has a gene which connects physical pain sensitivity with social pain sensitivity.
The findings back the common theory that rejection ‘hurts’ by showing that a gene regulating the body’s most potent painkillers – mu-opioids – is involved in socially painful experiences too.
Whole grains pack a powerful antioxidant punch along with their well-known fiber muscle, according to a new study.
For the first time, researchers have measured the total antioxidant content of many popular breakfast cereals and whole-grain snacks, and it turns out that the fiber powerhouses are also heavyweights in the cancer-fighting antioxidant division as well.
Raisin Bran and popcorn topped the list, but the study shows that many other popular whole-grain breakfast cereals and snacks may be an overlooked source of healthy antioxidants known as polyphenols.
Depression is well known for dulling people’s sense of pleasure, and now, researchers have used high-tech brain scans to watch that happen inside the depressed brain.
Their findings — which appear in the advance online edition of NeuroReport — show that when depressed people listened to music they liked, the brain’s reward-processing areas weren’t as active as when people who weren’t depressed listened to their favorite music.
The masterpieces that spring from the talents of Rembrandt, Van Gogh and other artists often begin with the creation of a gradient of colors on a palette. In a similar manner, researchers at the National Institute of Standards and Technology (NIST) have created an innovative device called the “microfluidic palette” to produce multiple, steady-state chemical gradients—gradual changes in concentration across an area—in a miniature chamber about the diameter of a pinhead. The tool can be used to study the complex biological mechanisms in cells responsible for cancer metastasis, wound healing, biofilm formation and other fluid-related processes.
Music, rather than electromechanical valves, can drive experimental samples through a lab-on-a-chip in a new system developed at the University of Michigan. This development could significantly simplify the process of conducting experiments in microfluidic devices.
A paper on the research will be published online in the Proceedings of the National Academy of Sciences the week of July 20. Read the rest of this entry »
Much attention of nanotechnology researchers has recently been paid to the fabrication of free-standing, ultra-thin films. These systems have been developed for use in a wide variety of fields such as nano-separation membranes or nanosensors for electrochemical and photochemical applications. In a first report on the fabrication of free-standing nanosheets for biomedical applications, scientists in Japan have developed a biodegradable thin film of only about 20 nanometers thickness that could replace surgical stitches.
Bacteria play a role in myriad industrial processes from fermentation to cleaning up environmental pollution. But floating freely in solution, the microbial cells constantly multiply, generating biomass that must be removed periodically, causing downtime. Additionally, the microorganisms cannot be localized to a specific region of interest.
Now, scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and Stony Brook University have devised a way to encapsulate bacteria in a synthetic polymer hydrogel. These new, stable, bio-hybrid materials maintain the microbes’ ability to exchange nutrients and metabolic products with their environment, and could find widespread applications, for example, as biosensors, catalysts, drug-delivery systems, or in wastewater treatment. The method and results are described in a paper published online by the Proceedings of the National Academy of Sciences the week of August 3, 2009.
Twelve months after receiving an experimental gene therapy for a rare, inherited form of blindness, a patient discovered that she could read an illuminated clock in the family car for the first time in her life. The unexpected findings suggest that the brain can adapt to new sensory capacity, even in people who have been blind since birth.
A production line for uniform lipid-coated microspheres has been created by Japanese scientists. Using a microfluidic device, the team can continuously generate fluid-filled vesicles that are all the same size and all have a single lipid bilayer surrounding them, and could one day be used in drug delivery or artificial cells.
A Dresden research team used laser tweezers to measure the friction between a single motor protein molecule and its track. The team found that also within our cells, motors work against the resistance of friction and are restrained in its operation—usually by far not as much though as their macroscopic counterparts. These first experimental measurements of protein friction could help researchers to better understand key cellular processes such as cell division which is driven by such molecular machines. Read the rest of this entry »
Researchers have found another reason to eat well: a healthy diet helps prevent kidney stones. Loading up on fruits, vegetables, nuts, low-fat dairy products, and whole grains, while limiting salt, red and processed meats, and sweetened beverages is an effective way to ward off kidney stones, according to a study appearing in an upcoming issue of theJournal of the American Society Nephrology (JASN). Because kidney stones are linked to higher rates of hypertension, diabetes, increased body weight, and other risk factors for heart disease, the findings have considerable health implications. Read the rest of this entry »
Science, the journal of scientific research, news, and commentary published by The American Association for the Advancement of Science (AAAS), and JoVE, the scientific video journal, announced that they have entered into a partnership for joint production and publication of scientific videos online. The purpose of the partnership is to enhance scientific articles published in Science through video demonstrations of experimental techniques. Read the rest of this entry »
Researchers at the California Institute of Technology (Caltech) and their colleagues in 30 laboratories worldwide have released a new set of standards for graphically representing biological information—the biology equivalent of the circuit diagram in electronics. This visual language should make it easier to exchange complex information, so that biological models are depicted more accurately, consistently, and in a more readily understandable way.
The new standard, called the Systems Biology Graphical Notation (SBGN), was published in the August 8 issue of the journal Nature Biotechnology.
Death rates from cancer have been decreasing in all age groups in recent years, but the steepest declines have been among younger people, a new study shows.
The findings suggest that measures for prevention, screening, and treatment are leading to lower death rates, researchers report in Cancer Research, a journal of the American Association for Cancer Research.
Researchers used stem cells to grow a replacement tooth for an adult mouse, the first time scientists have developed a fully functioning three-dimensional organ replacement, according to a report in the Proceedings of the National Academy of Sciences. The researchers at the Tokyo University of Science created a set of cells that contained genetic instructions to build a tooth, and then implanted this “tooth germ” into the mouse’s empty tooth socket. The tooth grew out of the socket and through the gums, as a natural tooth would. Once the engineered tooth matured, after 11 weeks, it had a similar shape, hardness and response to pain or stress as a natural tooth, and worked equally well for chewing. The researchers suggested that using similar techniques in humans could restore function to patients with organ failure.
Knocking out genes with a role in cancer prevention helps produce stem cells.
Switching off the p53 pathway helped researchers to make stem-like cells.
Women with a family history of breast cancer who have ever breastfed reduce their risk of getting premenopausal breast cancer by nearly 60%, according to a new study.
he cancer stem cells that drive tumor growth and resist chemotherapies and radiation treatments that kill other cancer cells aren’t invincible after all. Researchers reporting online on August 13th in the journal Cell, a Cell Press publication, have discovered the first compound that targets those cancer stem cells directly. Read the rest of this entry »
A novel technique allows researchers to efficiently and precisely modify or introduce genes into the genomes of human embryonic stem cells (ESCs) and induced pluripotent stem (iPS) cells, according to Whitehead scientists. The method uses proteins called zinc finger nucleases and is described in the August 13 issue of Nature Biotechnology.
For unknown reasons, the human brain distinctly separates the handling of images of living things from images of non-living things, processing each image type in a different area of the brain. For years, many scientists have assumed the brain segregated visual information in this manner to optimize processing the images themselves, but new research shows that even in people who have been blind since birth the brain still separates the concepts of living and non-living objects.
The research, published in today’s issue of Neuron, implies that the brain categorizes objects based on the different types of subsequent consideration they demand—such as whether an object is edible, or is a landmark on the way home, or is a predator to run from. They are not categorized entirely by their appearance. Read the rest of this entry »
Scientists have discovered the first gene involved in regulating the optimal length of human sleep, offering a window into a key aspect of slumber, an enigmatic phenomenon that is critical to human physical and mental health.
The team, reporting in the Aug. 14, 2009 issue of Science, identified a mutated gene that allows two members of an extended family to thrive on six hours of sleep a day rather than the eight to eight-and-a-half hours that studies have shown humans need over time to maintain optimal health. Working from this discovery, the scientists genetically engineered mice and fruit flies to express the mutated gene and study its impact. Read the rest of this entry »
New research with transgenic mice reveals that a therapy directed at the muscle significantly improves disease symptoms of a genetic disorder characterized by destruction of the neurons that control movement. The study, published by Cell Press in the August 13th issue of the journal Neuron, highlights a promising new treatment for this currently incurable and nontreatable neurodegenerative disorder. Read the rest of this entry »
Posted August 13, 2009on:
A new study by researchers at Columbia University Mailman School of Public Health’s Center for Infection and Immunity indicates that pediatric obsessive-compulsive disorder (OCD), Tourette syndrome and/or tic disorder may develop from an inappropriate immune response to the bacteria causing common throat infections. The mouse model findings, published online by Nature Publishing Group in this week’s Molecular Psychiatry, support the view that this condition is a distinct disorder, and represent a key advance in tracing the path leading from an ordinary infection in childhood to the surfacing of a psychiatric syndrome. The research provides new insights into identifying children at risk for autoimmune brain disorders and suggests potential avenues for treatment. Read the rest of this entry »
Short-term memory getting worse? Exercise getting harder? Examine your diet. New research published online in The FASEB Journal (http://www.fasebj.org) showed that in less than 10 days of eating a high-fat diet, rats had a decreased ability to exercise and experienced significant short-term memory loss. These results show an important link between what we eat, how we think, and how our bodies perform. Read the rest of this entry »
Researchers have used a new machine that sequences millions of small DNA fragments in parallel to cover 90 percent of one individual’s genome in only four weeks.
hnica.com/science/news/2009/08/human-genome-completed-using-one-machine-for-four-weeks.ars’>1 machine, 4 weeks now enough to sequence human genome – Ars Technica.
Certain patients with colorectal cancer who begin regular aspirin use after the disease develops may greatly improve their odds of survival, researchers in Boston report.
Posted August 12, 2009on:
A new study finds a surprising similarity in the way neural circuits linked to vision process information in both sighted individuals and those who have been blind since birth. The research, published by Cell Press in the August 13th issue of the journal Neuron, reveals that category-specific localized activation of a critical part of the visual cortex does not require any prior visual experience and provides fascinating and valuable insight into the evolutionary history of the human brain. Read the rest of this entry »
Supplementing obese rats with the nutrient carnitine helps the animals to clear the extra sugar in their blood, something they had trouble doing on their own, researchers at Duke University Medical Center report.
A team led by Deborah Muoio (Moo-ee-oo), Ph.D., of the Duke Sarah W. Stedman Nutrition and Metabolism Center, also performed tests on human muscle cells that showed supplementing with carnitine might help older people with prediabetes, diabetes, and other disorders that make glucose (sugar) metabolism difficult.
When we absorb new information, the human brain reshapes itself to store this newfound knowledge. But where exactly is the new knowledge kept, and how does that capacity to adapt reflect our risk for Alzheimer’s disease and other forms of senile dementia later in our lives?
Dr. Yaniv Assaf of Tel Aviv University’s Department of Neurobiology is pioneering a new way to track the effect of memory on brain structure. “With a specific MRI methodology called ‘Diffusion Imaging MRI,’ we can investigate the microstructure of the tissue without actually cutting into it,” he explains. “We can measure how much capacity our brain has to change structurally, what our memory reserve is and where that happens.” Read the rest of this entry »
NEUROSCIENTISTS ARE MAPPING OUT A COMPLETE ATLAS OF CONNECTIVITY IN THE HUMAN BRAIN, BUT WHAT’S EMERGING IS A BATTLE OF SCALES.
People who mostly follow the Mediterranean diet lower their risk of mental decline — and they lower this risk even more if they exercise, new studies suggest.
It has long been thought that damage to the heart is irreversible, but new research is challenging that assumption.
Investigators from Children’s Hospital Boston were able to reverse heart damage in mice by stimulating the growth of new heart muscle cells.
They did this by injecting the mice with the growth factor neuregulin1, which is a key player in heart cell growth.
‘Jumping genes’ create diversity in human brain cells, offering clues to evolutionary and neurological disease
Posted August 10, 2009on:
Rather than sticking to a single DNA script, human brain cells harbor astonishing genomic variability, according to scientists at the Salk Institute for Biological Studies. The findings, to be published in the Aug. 5, 2009, advance online edition of Nature, could help explain brain development and individuality, as well as lead to a better understanding of neurological disease.
Researchers at the European Molecular Biology Laboratory (EMBL) and the University Clinic Heidelberg used cryoelectron tomography to peer at the structure of immature HIV, the precursor of the infectious variety. Turns out it has a fairly simple shape of a hexameric lattice that grows and seemingly randomly absorbs new proteins into the structure
Image: Top: Sections through tomograms of (A) immature virus particles and (B) in-vitro-assembled Gag particles. Scale bar, 100 nm.
When President Barack Obama said in his weekly radio address Saturday that innovation would be a key to the future of the nation, he probably was not thinking specifically of artificial brains or replacement eyeballs.
But other researchers already have such goals in mind and are well on their way to building Humans 2.0, the real-life Steve Austin of the “Six Million Dollar Man.”
Whether because exercise makes us hungry or because we want to reward ourselves, many people eat more — and eat more junk food, like doughnuts — after going to the gym.
Unlike most beverages, grapefruit juice contains a chemical that boosts the potency of many drugs in the body. To avoid a dangerously high dose of medication, patients are often advised to not wash down pills with grapefruit juice. U. of C. cancer researcher Dr. Ezra Cohen wondered if that quality could be used for good — if drinking the juice could boost the effectiveness of cancer drugs.
Changing sexual practices have led to a dramatic rise in throat cancer in the United States over the past two decades, and experts say they fear an epidemic of the disease.
The comments were made Wednesday at a news conference held by the American Association for Cancer Research to discuss research into the role of the sexually transmitted human papilloma virus ( HPV) in head and neck cancer.
Increasing rates of HPV infection, spread through oralsex, is largely driving the rapid rise in oropharyngeal cancers, which include tumors of the throat, tonsils, and base of the tongue, said Scott Lippman, MD, who chairs the thoracic department at the University of Texas M.D. Anderson Cancer Center.
Studies of oropharyngeal tumor tissue stored 20 years ago show that only around 20% are HPV positive, Lippman said. Today it is estimated that 60% of patients are infected with the virus.
Self-control is one of our most cherished values. We applaud those who have the discipline to regulate their appetites and actions, and we try hard to instill this virtue in our children. Think of the marketing slogans that key off the desire for restraint: “Just say no.” “Just do it.” We celebrate the power of the mind to make hard choices, despite our emotions or other temptations, and keep us on course.
But what if we can’t just do it? What if “it” is too difficult or if our strategy for success is misguided? Is it possible that willpower actually might be an obstacle rather than a means to happiness and harmony? Can we have too much of a good thing?
Microbes normally create a charge difference in the course of their metabolism, but they don’t always respond well when humans try to harness that difference for usable energy. Researchers have now evolved some bacteria that tolerate life inside a fuel cell better, and produce twice the current.
The promise of stem cell therapy may lie in uncovering how adult cells revert back into a primordial, stem cell state, whose fate is yet to be determined. Now, cell scientists at the Johns Hopkins University School of Medicine have identified key molecular players responsible for this reversion in fruit fly sperm cells. Reporting online this week in Cell Stem Cell, researchers show that two proteins are responsible redirecting cells on the way to becoming sperm back to stem cells. Read the rest of this entry »
As politicians try to reform a health care system that could swallow one-fifth of the nation’s economic output by 2020, they should consider making a small bet with a potentially huge payoff: research that could slow the process of aging.
A chemical found in blueberry leaves has shown a strong effect in blocking the replication of the Hepatitis C virus, opening up a new avenue for treating chronic HCV infections, which affect 200 million people worldwide and can eventually lead to cirrhosis and liver cancer. Read the rest of this entry »