Oxygen on the Brain

AN ANCIENT CELLULAR PROGRAM to protect cells when oxygen is low seems crucial for the production of new brain cells.

For more than two billion years on this planet, O2 has been the go-to gas for generating efficient cellular energy. But life on Earth never takes oxygen for granted. “When it runs low, cells swiftly adapt,” says cell biologist Celeste Simon.

This ancient adaptive reaction, known as the low-oxygen, or hypoxia, response, typically involves a cascade of protective changes in cells: protein synthesis drops and cells switch to a less efficient process of energy production that doesn’t require oxygen. But organisms have evolved uses for the hypoxia response that are not merely protective.

Simon, an HHMI investigator at the University of Pennsylvania, recently found evidence that the response is crucial for maintaining the health of stem cells in the hippocampus, a key memory region of the brain. The discovery could alter our understanding of a host of stem cell-related brain conditions.

via HHMI Bulletin May 2011: Oxygen on the Brain.


A Nanotube Patch to Help Heal the Heart 

Researchers create carbon nanotubes that mimic natural tissue and can regenerate heart cells in a dish.

A conductive patch of carbon nanotubes can regenerate heart tissue growing in a dish, according to preliminary research from Brown University. The patch, made of tiny chains of carbon atoms that fold in on themselves, forming a tube, conducts electricity and mimics the rough surface of natural tissue. The more nanotubes the Brown researchers added to the patch, the more cells around it were able to regenerate.

Have a heart: Brown University researchers have created a tiny patch made out of carbon nanotubes that they hope will someday help regenerate heart cells.

Credit: Thomas Webster at Brown University

via A Nanotube Patch to Help Heal the Heart  – Technology Review.

Dietary Supplement May Help Prevent Preeclampsia

An inexpensive dietary supplement appears to help prevent the serious pregnancy complication preeclampsia in high-risk women, according to a new study.

But researchers say the effect in lower-risk pregnancies remains to be determined.

In the study from Mexico, women who ate daily food bars containing the amino acid L-arginine and antioxidant vitamins during pregnancy had a much lower incidence of preeclampsia than women who ate bars containing the antioxidant vitamins alone or bars containing neither supplement

via Dietary Supplement May Help Prevent Preeclampsia.

Tiny variation in one gene may have led to crucial changes in human brain

The human brain has yet to explain the origin of one its defining features — the deep fissures and convolutions that increase its surface area and allow for rational and abstract thoughts.

An international collaboration of scientists from the Yale School of Medicine and Turkey may have discovered humanity’s beneficiary — a tiny variation within a single gene that determines the formation of brain convolutions — they report online May 15 in the journal Nature Genetics.

On the left, the occipital region of a normal human brain is circled. On the right, the same area of the brain of a subject with mutation of LAMC3 gene is smooth, and lacks normal folds and convolutions. (Credit: courtesy of Yale University) Continue reading “Tiny variation in one gene may have led to crucial changes in human brain”

Reprogrammed cells trigger immune reactions in mice

Cells that have been reprogrammed to grow into different types of tissue might be rejected by the body — even when they are transplanted into the individual from whom they are made, researchers report in a study published today in Nature1.The study was led by Yang Xu, a molecular biologist at the University of California, San Diego. It will shake up the regenerative-medicine field, because until now, most scientists have assumed that reprogrammed cells made from an individuals own tissue could be safely transplanted back into the same person.

iPS cells

via Reprogrammed cells trigger immune reactions in mice : Nature News.

A new program for neural stem cells

Neural stem cells can do a lot, but not everything. For example, brain and spinal cord cells are not usually generated by neural stem cells of the peripheral nervous system, and it is not possible to produce cells of the peripheral nervous system from the stem cells of the brain. However, researchers from the Max Planck Institute for Brain Research in Frankfurt and the Max Planck Institute of Immunobiology and Epigenetics in Freiburg have now succeeded in producing central nervous system cells from neural stem cells of the peripheral nervous system. They found that if peripheral stem cells are maintained under defined growth conditions, they generate oligodendrocytes, which form the myelin layer that surrounds the neurons found in the brain and spinal cord.

Transplantation of reprogrammed neural stem cells into the brains of genetically modified mice, which cannot form myelin. The stem cells develop oligodendrocytes (green), which form myelin (red). Continue reading “A new program for neural stem cells”

Sound Test Might Signal Minimal Consciousness

Talk between the brain’s decision-making center, or frontal cortex, and other brain regions might distinguish aware individuals from those stripped of conscious thought. Identifying such signaling malfunctions could speed the diagnosis of vegetative states and give scientists insight into such devastating disorders, an international team of researchers reports May 12 in Science.

Today, diagnosing a vegetative brain is an uncertain enterprise, says John Whyte, director of the Moss Rehabilitation Research Institute in Elkins Park, Pa. Patients classified as vegetative can’t act in any purposeful way under any observable circumstances. Patients deemed minimally conscious, however, show some capacity to understand and interact with the world — for instance, by moving a finger on command. Distinguishing between the two can take weeks of behavioral testing, and misdiagnoses are common.The flow of information in the brain might be a crucial element of why patients in vegetative states can’t move or speak on their own accord

The flow of information in the brain might be a crucial element of why patients in vegetative states can’t move or speak on their own accord
Image credits: University of Liège / © comascience.org

via Sound Test Might Signal Minimal Consciousness | Wired Science | Wired.com.

An Inside Look at the Teen Brain

Eva-Marie Fredric thought her then-14-year-old son, Dylan, could handle the task of packing for their trip to the mountains. But when the two arrived at the campsite, she found the tent — but no tent poles. “We slept outside on an inflated air mattress, freezing our bums off, with the dog huddled between us,” recalls the L.A.-based writer and producer.

Teens often frustrate their parents with their inability to remember key information and keep track of their stuff. Part of the problem is that their brains are not developed enough to do these things consistently and well, says Doris Trauner, MD, professor of neurosciences and chief of pediatric neurology at the University of California, San Diego School of Medicine.

via An Inside Look at the Teen Brain.

How to control complex networks

At first glance, a diagram of the complex network of genes that regulate cellular metabolism might seem hopelessly complex, and efforts to control such a system futile.However, an MIT researcher has come up with a new computational model that can analyze any type of complex network — biological, social or electronic — and reveal the critical points that can be used to control the entire system. Potential applications of this work, which appears as the cover story in the May 12 issue of Nature, include reprogramming adult cells and identifying new drug targets, says study author Jean-Jacques Slotine, an MIT professor of mechanical engineering and brain and cognitive sciences.

MIT and Northeastern University researchers devised a computer algorithm that can generate a controllability structure for any complex network. The red points are driver nodes, which can control the rest of the nodes green.Image: Mauro Martino

via How to control complex networks.

The Human Body, Searchable in 3-D

The first online 3-D interactive search tool of the human body was released today.  It allows a user to view and navigate the human anatomy, male or female, down to the finest detail—from the muscles and deep muscles to the nerves, arteries, vessels, and bones. This new tool, called BodyMaps, was developed by Healthline Networks, a company that provides medical information to consumers online, and GE Healthyimagination, a Web-based platform that shares and promotes projects that focus on consumer health, such as apps or healthy how-to videos.

Anatomical views: BodyMaps, a 3-D visual search tool, allows a user to search and navigate the human body. Shown at left is the left ventricle of the heart. Pop-up text gives definitions, descriptions, and common conditions. At right, the “deep muscle” view of the knee shows layers of the body from the skin and muscles down to the arteries, vessels, and bones. 

Credit: Healthline and GE Healthyimagine

via The Human Body, Searchable in 3-D – Technology Review.

Sense of justice built into the brain

A new study from Karolinska Institutet in Sweden shows that the brain has built-in mechanisms that trigger an automatic reaction to someone who refuses to share. The reaction derives from the amygdala, an older part of the brain. The subjects’ sense of justice was challenged in a two-player money-based fairness game, while their brain activity was registered by an MR scanner. When bidders made unfair suggestions as to how to share the money, they were often punished by their partners even if it cost them. A drug that inhibits amygdala activity subdued this reaction to unfairness.

Team describes neurological basis for embarrassment

Recording people belting out an old Motown tune and then asking them to listen to their own singing without the accompanying music seems like an unusually cruel form of punishment. But for a team of scientists at the University of California, San Francisco and University of California, Berkeley, this exact Karaoke experiment has revealed what part of the brain is essential for embarrassment.

The twist to the experiment was that most of the subjects had neurodegenerative diseases, which helped scientists identify a thumb-sized bit of tissue in the right hemisphere of the front part of the brain called the “pregenual anterior cingulate cortex” as integral to embarrassment. Continue reading “Team describes neurological basis for embarrassment”

New Research Suggests Dramatic Shift In Understanding Of Personalized Medicine

Researchers at Mount Sinai School of Medicine, in collaboration with researchers at Loyola University Chicago Stritch School of Medicine, have made a critical discovery that may lead scientists to abandon the use of broad conventional ethnic labels—African-American, Hispanic, and Caucasian—to estimate a patient’s genetic risk for disease. This first-of-its kind study conducted with diverse patients receiving care at a single urban academic medical center, marks an important step in the clinical application of personalized medicine. The data are published online in the peer-reviewed journal PLoS ONE. Continue reading “New Research Suggests Dramatic Shift In Understanding Of Personalized Medicine”

Anti-inflammatory drug may fight breast cancer

German researchers have identified an unexpected molecular marker that predicts how sensitive hard-to-treat triple-negative breast cancers are to chemotherapy.

Triple-negative breast cancers –which do not express the genes for estrogen receptor, or progesterone receptor and do not have Her2/neu overexpression or amplification– are more aggressive than other forms of the disease and cannot be treated with endocrine or Her2 targeted therapies. Continue reading “Anti-inflammatory drug may fight breast cancer”

The soul of a cell: Researchers used advanced instrument to read cells’ minds

Researchers at the Stanford University School of Medicine have taken a machine already in use for the measurement of impurities in semiconductors and used it to analyze immune cells in far more detail than has been possible before. The new technology lets scientists take simultaneous measurements of dozens of features located on and in cells, whereas the existing technology typically begins to encounter technical limitations at about a half-dozen.

The investigators were able not only to simultaneously categorize more immune cell types than ever before seen at once but, at the same time, to peer inside those cells and learn how various internal processes differed from one cell type to the next.

Credit: Science

Continue reading “The soul of a cell: Researchers used advanced instrument to read cells’ minds”

Juice cocktail ‘good for heart’

A blend of fruit juices, including grape, cranberry and blackcurrant, may have benefits for the heart, research suggests.

French scientists tested the blend on pig arteries in the lab, and found it caused artery walls to relax.

It remains to be seen whether fruit juices can improve vascular health, they report in a scientific journal.

The study adds weight to evidence fruit and veg reduces heart disease risk, says the British Heart Foundatio

via BBC News – Juice cocktail ‘good for heart’.

Comprehensive study finds no link between XMRV retrovirus and chronic fatigue syndrome

New findings from University of Utah School of Medicine researchers show that the retrovirus called XMRV is not present in the blood of patients who have chronic fatigue syndrome (CFS). These findings contradict a widely reported 2009 Science study that linked CFS to XMRV.

The study, performed by a team of U of U researchers led by Ila R Singh, M.D., Ph.D., associate professor of pathology, was published May 4, 2011, in the Journal of Virology online, and is the most comprehensive to date regarding the purported link between chronic fatigue syndrome and XMRV. Continue reading “Comprehensive study finds no link between XMRV retrovirus and chronic fatigue syndrome”

Exercise protects the heart via nitric oxide

Exercise both reduces the risk of a heart attack and protects the heart from injury if a heart attack does occur. For years, doctors have been trying to dissect how this second benefit of exercise works, with the aim of finding ways to protect the heart after a heart attack.

Researchers at Emory University School of Medicine have identified the ability of the heart to produce and store nitric oxide as an important way exercise protects the heart from injury.

Nitric oxide, a short-lived gas generated within the body, turns on chemical pathways that relax blood vessels to increase blood flow and activate survival pathways. Both the chemical nitrite and nitrosothiols, where nitric oxide is attached to proteins via sulfur, appear to act as convertible reservoirs for nitric oxide in situations where the body needs it, such as a lack of blood flow or oxygen.

The Emory team’s results, published online in the journal Circulation Research, strengthen the case for nitrite and nitrosothiols as possible protectants from the damage of a heart attack.

The first author is John Calvert, PhD, assistant professor of surgery at Emory University School of Medicine. The senior author is David Lefer, PhD, professor of surgery at Emory University School of Medicine and director of the Cardiothoracic Research Laboratory at Emory University Hospital Midtown. Collaborators included scientists at University of Colorado, Boulder, and Johns Hopkins University.

“Our study provides new evidence that nitric oxide generated during physical exercise is actually stored in the bloodstream and heart in the form of nitrite and nitrosothiols. These more stable nitric oxide intermediates appear to be critical for the cardioprotection against a subsequent heart attack,” Lefer says.

Timing is key – the benefits of exercise don’t last In experiments with mice, the researchers showed that four weeks of being able to run on a wheel protected them from having a coronary artery was blocked; the amount of heart muscle damaged by the blockage was less after the exercise period. Importantly, the mice are still protected a week after the wheel is taken away.

The researchers found that voluntary exercise boosted levels of an enzyme that produces nitric oxide (eNOS, endothelial nitric oxide synthase). Moreover, the levels of eNOS in heart tissue, and nitrite and nitrosothiols in the blood as well as heart tissue, stayed high for a week after exercise ceased, unlike other heart enzymes stimulated by exercise. The protective effects of exercise did not extend beyond four weeks after the exercise period was over, when nitrite and nitrosothiols in the heart returned to baseline.

In mice that lack the eNOS enzyme, exercise did not protect the heart from a coronary blockage, although these mice appeared to lack the ability to exercise as much as normal mice.

Another molecule that appears to be important for the benefits of exercise is the beta-3-adrenergic receptor, which allows cells to respond to the hormones epinephrine and norepinephrine. All of the beneficial effects of voluntary exercise are lost in mice that are deficient in this receptor. One of the effects of stimulating the receptor appears to be activating eNOS. Additional animal studies are currently underway in Lefer’s lab to determine the potential benefit of beta-3-adrenergic receptor activating drugs following a heart attack.

Study: Many With ADHD Can’t Control Emotions

More than half of people with attention deficit hyperactivity disorder (ADHD) also have trouble regulating their emotions, and that difficulty may be passed through families, a new study shows.

Researchers are calling this cluster of symptoms deficient emotional self-regulation (DESR). It involves quick bursts of outsized anger, frustration, impatience, or excitability in response to everyday events.

“Any sort of reflexive, emotionally laden reaction that would not be politic or thoughtful or helpful,” says study researcher Craig B. H. Surman, MD. Surman is an instructor in psychiatry in the Massachusetts General Hospital Pediatric Psychopharmacology and Adult ADHD Program.

“It’s not just people with mental health challenges that have issues regulating their emotions. Everyone does to some extent, but hopefully, in most cases it’s when people are really maxed out or strained or stressed,” Surman says.

via Study: Many With ADHD Can’t Control Emotions.

Stem cell-related changes that may contribute to age-related cognitive decline identified

A new study from Cold Spring Harbor Laboratory (CSHL) offers an explanation for why our brains produce fewer and fewer neurons with age, a phenomenon thought to underlie age-related cognitive decline. The study, published as the cover story in the May 6 issue of Cell Stem Cell, suggests that this drop in production is due to the shrinking cache of adult stem cells in our brains.

Continue reading “Stem cell-related changes that may contribute to age-related cognitive decline identified”

Mutation provides new insight into the molecular mechanisms of aging

A new study identifies the mutation that underlies a rare, inherited accelerated-aging disease and provides key insight into normal human aging. The research, published by Cell Press online May 5 in the American Journal of Human Genetics, highlights the importance of a cellular structure called the “nuclear envelope” in the process of aging.

“Aging is a very complex process which affects most biological functions of an organism but whose molecular basis remains largely unknown,” explains Dr. Carlos López-Otín from the University of Oviedo in Spain. “Over the last few years, our knowledge of the molecular mechanisms underlying human aging has benefited from studies of premature-aging syndromes, such as Hutchinson-Gilford Progeria syndrome, that cause the early development of characteristics normally associated with advanced age.” Continue reading “Mutation provides new insight into the molecular mechanisms of aging”

Scientists show how shifts in temperature prime immune response

Researchers at The Scripps Research Institute have found a temperature-sensing protein within immune cells that, when tripped, allows calcium to pour in and activate an immune response. This process can occur as temperature rises, such as during a fever, or when it falls—such as when immune cells are “called” from the body’s warm interior to a site of injury on cooler skin.

The study, recently published online ahead of print by Nature Chemical Biology, is the first to find such a sensor in immune cells—specifically, in the T lymphocytes that play a central role in activation of killer immune cells. The protein, STIM1, previously known as an endoplasmic reticulum (ER) calcium sensor, had been thought to be important in immune function, and now the scientists show it is also a temperature sensor. Continue reading “Scientists show how shifts in temperature prime immune response”

Scientists engineer patch a heart

Researchers at Columbia Engineering have established a new method to patch a damaged heart using a tissue-engineering platform that enables heart tissue to repair itself. This breakthrough, recently published in the Proceedings of the National Academy of Sciences is an important step forward in combating cardiovascular disease, one of the most serious health problems of our day. Continue reading “Scientists engineer patch a heart”

Study takes closer look at calorie restrictors

Trent Arsenault has eaten the same breakfast, lunch and dinner almost every day for the past four or five years: a fruit smoothie in the morning, a spinach salad at noon and another fruit smoothie after work.

Every now and then he’ll add a snack to his day. Maybe a spoonful of almond butter or a few walnuts.

All in all, Arsenault consumes about 1,800 calories a day – or several hundred calories fewer than what a typical man his size would expect to eat.

But Arsenault is hardly typical. At 6 feet 1 inch tall, he weighs just 150 pounds, and he purposely restricts the calories he takes in because he believes a strict diet will allow him a much longer, healthier life than his peers.

via UCSF study takes closer look at calorie restrictors.

FDA Panel Urges Approval of Hepatitis C Drug

In an18-0 vote, an FDA advisory panel recommended approval of the drug boceprevir to treat hepatitis C.

Panel members called boceprevir, manufactured by Merck & Co., a weapon in the fight against chronic hepatitis C virus (HCV) genotype 1 infection. Chronic HCV genotype 1 infection is the most common form of hepatitis in the U.S. and also the most difficult to treat.

If approved by the FDA, boceprevir will have the brand name Victrelis.

Boceprevir is an antiviral medication called a protease inhibitor that has proven effective in adults with liver disease who have been untreated or who have failed previous therapy.  Protease inhibitors are commonly used to treat HIV infection. In the treatment of hepatitis C infection, boceprevir inhibits an enzyme, thereby suppressing replication of the hepatitis C virus.

Despite the committee’s affirmative vote, the advisors also had reservations about  boceprevir’s widespread usage.

via FDA Panel Urges Approval of Hepatitis C Drug.

Out-of-Africa migration selected novelty-seeking genes

AS HUMANS migrated out of Africa around 50,000 years ago and moved across the planet, evolution may have latched onto a gene linked to risk-taking and adventurousness.

The idea, first put forward by Chuansheng Chen at the University of California, Irvine, more than a decade ago, was originally met with scepticism. Now Luke Matthews of Harvard University and Paul Butler of Boston University have shown that a link between two versions of a specific gene and ancient migration patterns stands up to rigorous analysis.

The DRD4 gene codes for a dopamine receptor in the brain. It exists in several versions, or alleles, and studies have shown that people tend to have slightly different personality traits depending on which they have. The 4R allele, for instance, is associated with being even-tempered, reflective and prudent. The less common 7R and 2R versions have been linked to impulsive and exploratory behaviour, risk-taking and the ability to shrug off new situations. Matthews and Butler think that migrants with these versions were better able to deal with dangerous, fluctuating situations and more likely to survive and reproduce under those conditions.

via Out-of-Africa migration selected novelty-seeking genes – life – 06 May 2011 – New Scientist.

New evidence that caffeine is a healthful antioxidant in coffee

Scientists are reporting an in-depth analysis of how the caffeine in coffee, tea, and other foods seems to protect against conditions such as Alzheimer’s disease and heart disease on the most fundamental levels. The report, which describes the chemistry behind caffeine’s antioxidant effects, appears in ACS’ The Journal of Physical Chemistry B.

Annia Galano and Jorge Rafael León-Carmona describe evidence suggesting that coffee is one of the richest sources of healthful antioxidants in the average person’s diet. Some of the newest research points to caffeine (also present in tea, cocoa, and other foods) as the source of powerful antioxidant effects that may help protect people from Alzheimer’s and other diseases. However, scientists know little about exactly how caffeine works in scavenging the so-called free radicals that have damaging effects in the body. And those few studies sometimes have reached contradictory conclusions.

In an effort to bolster scientific knowledge about caffeine, they present detailed theoretical calculations on caffeine’s interactions with free radicals. Their theoretical conclusions show “excellent” consistency with the results that other scientists have report from animal and other experiments, bolstering the likelihood that caffeine is, indeed, a source of healthful antioxidant activity in coffee.

New Clues to Low-Calorie Diets and Longer Life

Research has suggested that very low-calorie diets may increase life expectancy in animals, and now a new study in humans provides some important clues as to why this may occur.

In the new study, individuals who had higher metabolic rates — the amount of energy the body uses for normal body functions — were more likely to die early from natural causes than those who had lower metabolic rates.

The new findings appear in the Journal of Clinical Endocrinology & Metabolism.

Higher metabolic rates may accelerate the natural aging process via the production of damaging free radicals. These substances are linked to many diseases of aging and may promote organ damage.

via New Clues to Low-Calorie Diets and Longer Life.

The benefits of meditation

Studies have shown that meditating regularly can help relieve symptoms in people who suffer from chronic pain, but the neural mechanisms underlying the relief were unclear. Now, MIT and Harvard researchers have found a possible explanation for this phenomenon.

In a study published online April 21 in the journal Brain Research Bulletin, the researchers found that people trained to meditate over an eight-week period were better able to control a specific type of brain waves called alpha rhythms.

via The benefitsof meditation.

Researchers Pinpoint Brain Region That Influences Gambling Decisions

When a group of gamblers gather around a roulette table, individual players are likely to have different reasons for betting on certain numbers. Some may play a “lucky” number that has given them positive results in the past—a strategy called reinforcement learning. Others may check out the recent history of winning colors or numbers to try and decipher a pattern. Betting on the belief that a certain outcome is “due” based on past events is called the gambler’s fallacy.

Recently, researchers at the California Institute of Technology (Caltech) and Ireland’s Trinity College Dublin hedged their bets—and came out winners—when they proposed that a certain region of the brain drives these different types of decision-making behaviors.
Continue reading “Researchers Pinpoint Brain Region That Influences Gambling Decisions”

Cancer Genomics

In the fall of 2006, a new machine arrived at what’s now known as the Genome Institute at Washington University in St. Louis. It was capable of reading DNA a thousand times as quickly as the facility’s earlier machines, and at far less cost. Elaine Mardis, the center’s codirector, immediately began using it to sequence cancer tissues, scouring their DNA for mutations. Just five years later, Mardis and her collaborators have sequenced both cancerous and healthy tissue from several hundred patients and identified tens of thousands of mutations. Some of the findings have led to new approaches to treating cancer, while others have opened new avenues of research.

via Cancer Genomics – Technology Review.

Brain Size of Children Yields Clues to Autism

Children with autism tend to have larger brains than children without autism, a study suggests.

The study shows larger brains are the result of accelerated brain growth around the children’s first birthday.

Researchers from the University of North Carolina also report that the brain overgrowth in kids who develop autism occurs in the temporal lobe white matter of the brain.

This finding could lead to a better understanding of the genes that drive autism, which, in turn, could lead to earlier identification and treatment of the disorder

via Brain Size of Children Yields Clues to Autism.

Removable ‘cloak’ for nanoparticles helps them target tumors

MIT chemical engineers have designed a new type of drug-delivery nanoparticle that exploits a trait shared by almost all tumors: They are more acidic than healthy tissues.

Such particles could target nearly any type of tumor, and can be designed to carry virtually any type of drug, says Paula Hammond, a member of the David H. Koch Institute for Integrative Cancer Research at MIT and senior author of a paper describing the particles in the journal ACS Nano.

Continue reading “Removable ‘cloak’ for nanoparticles helps them target tumors”

Pistachios pummel pretzels as a weight-wise snack

When it comes to healthy snacking and weight management, a new study bolsters the long-held view that not all calories are created equal. According to nutrition researchers at UCLA, choosing to snack on pistachios rather than pretzels as part of a healthy diet not only supports your body mass index (BMI) goals, but can support heart health too. Continue reading “Pistachios pummel pretzels as a weight-wise snack”

Mouse study turns fat-loss/longevity link on its head

Since the 1930s scientists have proposed food restriction as a way to extend life in mice. Though feeding a reduced-calorie diet has indeed lengthened the life spans of mice, rats and many other species, new studies with dozens of different mouse strains indicate that food restriction does not work in all cases.

Researchers at the UT Health Science Center San Antonio’s Barshop Institute for Longevity and Aging Studies, with colleagues at the University of Colorado, studied the effect of food restriction on fat and weight loss in 41 genetically different strains of mice. The scientists then correlated the amount of fat reduction to life span.

The answer: Mice that maintained their fat actually lived longer. Those that lost fat died earlier.

Continue reading “Mouse study turns fat-loss/longevity link on its head”

FDA Approves Prostate Cancer Drug Zytiga

he FDA has approved the Johnson & Johnson pill Zytiga for use in combination with the steroid prednisone to treat a certain type of late-stage prostate cancer in men who have already been treated with chemotherapy.

The medication is to be used to treat patients with metastatic, castration-resistant prostate cancer.

In men with prostate cancer,  the male sex hormone testosterone stimulates the tumor to grow.

The FDA says in a statement that drugs or surgery are used to reduce testosterone production or block the effects of testosterone, but that prostate cancer sometimes continues to grow, even when testosterone levels are low. Men with such cancers are said to have castration-resistant prostate cancer.

Zytiga (abiraterone acetate) targets a protein called CYP17A1, which the FDA says plays a key role in the production of testosterone.

The agency says the drug works by decreasing the production of testosterone that stimulates cancer cells to keep growing.

via FDA Approves Prostate Cancer Drug Zytiga.

Priming the Body to Tackle Cancer

Melanoma, one of the most common cancers, is usually treated with surgery and aggressive chemotherapy. In a new, preliminary study, Dr. Marcus O. Butler, of Boston’s Dana-Farber Cancer Institute, suggests a kinder, gentler way of treating melanoma, and perhaps other cancers, using the body’s own defense system.

In a study published in the April 27 edition of Science Translational Medicine, Butler and his colleagues harvested immune cells from nine patients. They souped up the cells in their lab—in effect giving them the ability to remember cancer cells—multiplied them in number, and infused them back into the patients from whom they been taken. This technique, called adoptive t-cell therapy, primes the immune system to seek out and destroy cancer cells throughout the body.

Arming the immune system: The black spots in this PET scan (left) indicate melanoma spread throughout a patient’s chest cavity. Seventy-four days after treatment with adoptive t-cell therapy, the cancer was gone, and it has not returned. Credit: Butler et al., Science Translational Medicine

via Priming the Body to Tackle Cancer – Technology Review.

Electrical Oscillations Found to be Critical for Storing Spatial Memories in Brain

Biologists at UC San Diego have discovered that electrical oscillations in the brain, long thought to play a role in organizing cognitive functions such as memory, are critically important for the brain to store the information that allows us to navigate through our physical environment.

The scientists report in the April 29 issue of the journal Sciencethat neurons called “grid cells” that create maps of the external environment in one portion of our brain require precisely timed electrical oscillations in order to function properly from another part of the brain that serves as a kind of neural pacemaker.

Their discovery has important implications for understanding the underlying causes of neurological diseases such as Alzheimer’s disease and for restoring memory in areas of the brain that are necessary for orientation.

Leutgeb grid cell field

Red dots signal the location of electrical impulses generated within this grid cell, which are needed for the brain to store information about the rat’s physical environment. 
Credit: UC San Diego

Continue reading “Electrical Oscillations Found to be Critical for Storing Spatial Memories in Brain”

Origami: Not just for paper anymore

While the primary job of DNA in cells is to carry genetic information from one generation to the next, some scientists also see the highly stable and programmable molecule as an ideal building material for nanoscale structures that could be used to deliver drugs, act as biosensors, perform artificial photosynthesis and more.

Trying to build DNA structures on a large scale was once considered unthinkable. But about five years ago, Caltech computational bioengineer Paul Rothemund laid out a new design strategy called DNA origami: the construction of two-dimensional shapes from a DNA strand folded over on itself and secured by short “staple” strands. Several years later, William Shih’s lab at Harvard Medical School translated this concept to three dimensions, allowing design of complex curved and bent structures that opened new avenues for synthetic biological design at the nanoscale

via Origami: Not just for paper anymore.