Memory Formation Triggered by Stem Cell Development

Researchers at the RIKEN-MIT Center for Neural Circuit Genetics have discovered an answer to the long-standing mystery of how brain cells can both remember new memories while also maintaining older ones.

They found that specific neurons in a brain region called the dentate gyrus serve distinct roles in memory formation depending on whether the neural stem cells that produced them were of old versus young age.
Continue reading “Memory Formation Triggered by Stem Cell Development”

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Iceman Was a Medical Mess

Few of our ancestors have been so thoroughly poked and prodded as Neolithic Tyrolean Iceman “Ötzi,” discovered melting out of an Alpine glacier in 1991. Researchers have probed his stomach and bowels for traces of his last meal and analyzed his teeth for cavities. Now, an international team has sequenced his entire genome, and it turns out Ötzi still has some surprises in store.

Earlier computer scans had revealed Ötzi’s severe arteriosclerosis, or hardening of the arteries. But the new analysis shows that Ötzi had a genetic predisposition to the condition, despite the fact that as a hunter-gatherer he had none of what are currently believed to be the relevant risk factors, such as being overweight, getting too little exercise, and smoking or drinking. “This new data suggests that we might be less able to prevent arteriosclerosis than we believed,” notes cardiologist and mummy expert Gregory Thomas of the University of California, Irvine, who was not involved in the new work.

sn-iceman.jpg

Coming to life. The genome of Ötzi the Iceman (body left, reconstruction right) holds a few surprises.
Credit: (reconstruction) Kennis and Kennis/South Tyrol Museum of Archaeology

via Iceman Was a Medical Mess – ScienceNOW.

Medical Imaging

Doctors struggle to keep squirming children still for long scans. Now, thanks to faster magnetic resonance imaging (MRI), they may no longer have to worry about keeping their patients still for so long. The above image of the blood flow through the heart of a 6-year-old with a congenital heart defect was acquired in 10 minutes rather than an hour, as with traditional MRI.

sn-FastMRI.jpg

Credit: Michael Lustig, Shreyas Vasanawala, Marcus Alley

via ScienceShot: Medical Imaging, In A Snap – ScienceNOW.

How to Control a Prosthesis With Your Mind

Imagine a piece of technology that would let you control an apparatus simply by thinking about it. Lots of people, it turns out, have dreamed of just such a system, which for decades has fired the imaginations of scientists, engineers, and science fiction authors. It’s easy to see why: By transforming thought into action, a brain-machine interface could let paralyzed people control devices like wheelchairs, prosthetic limbs, or computers. Farther out in the future, in the realm of sci-fi writers, it’s possible to envision truly remarkable things, like brain implants that would allow people to augment their sensory, motor, and cognitive abilities.

That melding of mind and machine suddenly seemed a little less far-fetched in 1999, when John Chapin, Miguel Nicolelis, and their colleagues at the MCP Hahnemann School of Medicine, in Philadelphia, and Duke University, in Durham, N.C., reported that rats in their laboratory had controlled a simple robotic device using brain activity alone. Initially, when the animals were thirsty, they had to use their paws to press a lever, thus activating a robotic arm that brought a straw close to their mouths. But after receiving a brain implant that recorded and interpreted activity in their motor cortices, the animals could just think about pressing the lever and the robotic arm would instantly give them a sip of water.

llustration: Bryan Christie Design

via How to Control a Prosthesis With Your Mind – IEEE Spectrum.

Bats harbour influenza

Fruit bats in Guatemala are hosting a novel subtype of influenza A virus, according to a study published today in the Proceedings of the National Academy of Sciences.

The virus — designated H17 — appears to have diverged from known influenza viruses long ago, shedding light on their evolution. Therefore, it seems to pose no immediate threat to humans. However, it is similar enough to other subtypes that genetic exchange with them could pose a risk. “We can’t say don’t worry about it, nor can we say it’s not dangerous. We just don’t know yet,” says study co-author Ruben Donis, chief of molecular virology and vaccines in the influenza division at the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia.

Donis and his colleagues are now testing bats in South America, Africa and Asia to document the geographical distribution of influenza — the first step towards determining whether bats are a reservoir behind outbreaks in humans

via Bats harbour influenza : Nature News & Comment.

How Your Cat Is Making You Crazy

Jaroslav Flegr is no kook. And yet, for years, he suspected his mind had been taken over by parasites that had invaded his brain. So the prolific biologist took his science-fiction hunch into the lab. What he’s now discovering will startle you. Could tiny organisms carried by house cats be creeping into our brains, causing everything from car wrecks to schizophrenia?

NO ONE WOULD accuse Jaroslav Flegr of being a conformist. A self-described “sloppy dresser,” the 53-year-old Czech scientist has the contemplative air of someone habitually lost in thought, and his still-youthful, square-jawed face is framed by frizzy red hair that encircles his head like a ring of fire.

Certainly Flegr’s thinking is jarringly unconventional. Starting in the early 1990s, he began to suspect that a single-celled parasite in the protozoan family was subtly manipulating his personality, causing him to behave in strange, often self-destructive ways. And if it was messing with his mind, he reasoned, it was probably doing the same to others.

via How Your Cat Is Making You Crazy – Magazine – The Atlantic.

How many neurons make a human brain? Billions fewer than we thought

How many neurons are there in the human brain? It was a question that scientists thought they had nailed – and the answer was 100bn (give or take). If you went looking you would find that figure repeated widely in the neuroscience literature and beyond.

But when a researcher in Brazil called Dr Suzana Herculano-Houzel started digging, she discovered that no one in the field could actually remember where the 100bn figure had come from – let alone how it had been arrived at. So she set about discovering the true figure (HT to the excellent Nature neuroscience podcast NeuroPod).

This involved a remarkable – and to some I suspect unsettling – piece of research. Her team took the brains of four adult men, aged 50, 51, 54 and 71, and turned them into what she describes as “brain soup”. All of the men had died of non-neurological diseases and had donated their brains for research.

 

Human brain on a plate

via How many neurons make a human brain? Billions fewer than we thought | James Randerson | Science | guardian.co.uk.

Bacteria-Killing Viruses Wield an Iron Spike

Forget needles in haystacks. Try finding the tip of a needle in a virus. Scientists have long known that a group of viruses called bacteriophages have a knack for infiltrating bacteria and that some begin their attack with a protein spike. But the tip of this spike is so small that no one knew what it was made of or exactly how it worked. Now a team of researchers has found a single iron atom at the head of the spike, a discovery that suggests phages enter bacteria in a different way than surmised.

Wherever there are bacteria you will find bacteriophages; digestive tracts, contaminated water, and feces are usually a good start. These viruses begin their dirty work by drilling into the outer membrane of bacteria. Once completely through all of a bug’s defenses, the phages inject their DNA, which essentially turns the bacterium into phage-producing factories. Eventually, the microbes become filled with so many viruses that they burst, releasing a new horde of phages into the environment.

via Bacteria-Killing Viruses Wield an Iron Spike – ScienceNOW.

Sleeping pills increase risk of death, study suggests

Doctors are calling for a rethink of the use of sleeping pills after a large study showed that the drugs carry a substantially increased risk of death for those who are prescribed them.

Commonly used sleeping pills, or “hypnotics”, such as temazepam and zolpidem, which is prescribed for short-term insomnia, are associated with more than a fourfold risk of death, according to the study published in the BMJ Open journal.

The study was carried out in the US, where up to 10% of the adult population took sleeping pills in 2010. The authors estimate that sleeping pills may have been associated with 320,000 to 507,000 extra deaths in the US that year.

via Sleeping pills increase risk of death, study suggests | Science | The Guardian.

Almonds are the new red

The American Heart Association (AHA) recently certified almonds based on their nutrient profile to display the signature Heart-Check mark . The Heart-Check mark is overseen by AHA to help make it easier for shoppers to identify and choose heart-healthy foods. This symbol is the most consumer-trusted nutrition icon appearing on packaged foods—in fact, research shows that more than half of shoppers use the mark as a deciding factor when choosing to purchase a new product.1 Consumers can now easily identify almonds as a heart-healthy choice.

In 2003, the U.S. Food and Drug Administration (FDA) issued a qualified health claim recognizing that consuming most nuts, including almonds, as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease.2 In addition, nearly two decades of research support the role of almonds in helping to maintain a healthy heart and healthy cholesterol levels.
Continue reading “Almonds are the new red”

Researchers discover how vitamin D inhibits inflammation

Researchers at National Jewish Health have discovered specific molecular and signaling events by which vitamin D inhibits inflammation. In their experiments, they showed that low levels of Vitamin D, comparable to levels found in millions of people, failed to inhibit the inflammatory cascade, while levels considered adequate did inhibit inflammatory signaling. They reported their results in the March 1, 2011, issue of The Journal of Immunology.

Continue reading “Researchers discover how vitamin D inhibits inflammation”

Citrus Fruits May Lower Women’s Stroke Risk

Researchers have identified a compound found in oranges, grapefruits, and other citrus fruits that may lower a woman’s stroke risk.

Previous studies suggest that eating fruits and vegetables helps protect against strokes, and many believe that antioxidant compounds known as flavonoids may explain why, because they have been shown to improve blood vessel function and they have anti-inflammatory effects.

Among other things, flavonoids give fruits and veggies their vibrant colors. They are also found in chocolate and red wine. By some estimates there are more than 5,000 of them.

In the newly published study, flavonoids abundant in citrus fruits known as flavanones appeared to give the most protection against stroke.

Women whose diets included the highest amount of flavanones had a 19% lower risk of suffering a blood-clot-related stroke than women with the lowest intake of the compound.

via Citrus Fruits May Lower Women’s Stroke Risk.

What’s Wrong With the Teenage Mind?

“What was he thinking?” It’s the familiar cry of bewildered parents trying to understand why their teenagers act the way they do.

How does the boy who can thoughtfully explain the reasons never to drink and drive end up in a drunken crash? Why does the girl who knows all about birth control find herself pregnant by a boy she doesn’t even like? What happened to the gifted, imaginative child who excelled through high school but then dropped out of college, drifted from job to job and now lives in his parents’ basement?

Adolescence has always been troubled, but for reasons that are somewhat mysterious, puberty is now kicking in at an earlier and earlier age. A leading theory points to changes in energy balance as children eat more and move less.

[TEENCOVER]

via What’s Wrong With the Teenage Mind? – WSJ.com.

Stem cells could drive hepatitis research forward

Hepatitis C, an infectious disease that can cause inflammation and organ failure, has different effects on different people. But no one is sure why some people are very susceptible to the infection, while others are resistant.

Scientists believe that if they could study liver cells from different people in the lab, they could determine how genetic differences produce these varying responses. However, liver cells are difficult to obtain and notoriously difficult to grow in a lab dish because they tend to lose their normal structure and function when removed from the body.

Now, researchers from MIT, Rockefeller University and the Medical College of Wisconsin have come up with a way to produce liver-like cells from induced pluripotent stem cells, or iPSCs, which are made from body tissues rather than embryos; the liver-like cells can then be infected with hepatitis C. Such cells could enable scientists to study why people respond differently to the infection.

via Stem cells could drive hepatitis research forward – MIT News Office.

Scientists decode ‘internal voices’

Researchers have demonstrated a striking method to reconstruct words, based on the brain waves of patients thinking of those words.

The technique reported in PLoS Biology relies on gathering electrical signals directly from patients’ brains.

Based on signals from listening patients, a computer model was used to reconstruct the sounds of words that patients were thinking of.

The method may in future help comatose and locked-in patients communicate.

via BBC News – Science decodes ‘internal voices’.

Human Brains Wire Up Slowly but Surely

As the father-to-son exchange in the old Cat Stevens song advised, “take your time, think a lot, … think of everything you’ve got.” Turns out the mellow ’70s folkie had stumbled upon what may explain a key feature of our brains that sets us apart from our closest relatives: We unhurriedly make synaptic connections through much of our early childhoods, and this plasticity enables us to slowly wire our brains based on our experiences.

Given that humans and chimpanzees share 98.8% of the same genes, researchers have long wondered what drives our unique cognitive and social skills. Yes, chimpanzees are smart and cooperative to a degree, but we clearly outshine them when it comes to abstract thinking, self-regulation, assimilation of cultural knowledge, and reasoning abilities. Now a study that looks at postmortem brain samples from humans, chimpanzees, and macaques collected from before birth to up to the end of the life span for each of these species has found a key difference in the expression of genes that control the development and function of synapses, the connections among neurons through which information flows.

via Human Brains Wire Up Slowly but Surely – ScienceNOW.

What Happens When Brain Hits Skull

Concussion, the most common among traumatic brain injuries, which occurs 1.7 million times a year in the U.S., represents a major public-health problem. It occurs when there is a sudden acceleration or deceleration of the head, a process depicted here in this animation.

A blow can produce a brief loss of consciousness, headaches and impaired cognition, among other symptoms. Symptoms can last for days or sometimes longer. And a person who experience one risks another and may find recovery takes longer.

Scientists continue to learn more about the nefarious consequences of repeated concussions. In the February issue of Scientific American, writer Jeffrey Bartholet details in “The Collision Syndrome evidence for yet another neurodegenerative disorder that can result from concussions.

via Inside Story: What Happens When Brain Hits Skull: Scientific American.

Depression Is Linked to Hyperconnectivity of Brain Regions, a New Study Shows

A study published today provides surprising new insight into what happens in depressed brains.

In people with depression, brain regions appear to be overly connected to one another, says the study, which is being published by UCLA’s Semel Institute for Neuroscience and Human Behavior. In turn, this excessive connectivity reduces the flexibility the brain needs to function properly.

via Depression Is Linked to Hyperconnectivity of Brain Regions, a New Study Shows – The Daily Beast.

Simulating How Proteins Self-Assemble, Or Fold

 

Proteins control nearly all of life’s functions, but how they self-assemble, or fold, is an unsolved problem in biology. Understanding how folding goes awry could lead to cures for diseases caused by protein misfolding, like Alzheimer’s and Parkinson’s. Stanford chemistry Professor Vijay Pande’s project Folding@home borrows computing time from home computers to simulate how proteins fold. By modeling protein folding, Pande says, “We hope to get exquisite detail and information that you might not be able to get from experiments.”

Transplant jaw made by 3D printer claimed as first

A 3D printer-created lower jaw has been fitted to an 83-year-old woman’s face in what doctors say is the first operation of its kind.

The transplant was carried out in June in the Netherlands, but is only now being publicised.

The implant was made out of titanium powder – heated and fused together by a laser, one layer at a time.

Technicians say the operation’s success paves the way for the use of more 3D-printed patient-specific parts.

The surgery follows research carried out at the Biomedical Research Institute at Hasselt University in Belgium, and the implant was built by LayerWise – a specialised metal-parts manufacturer based in the same country.

3D-printed jaw

 

via BBC News – Transplant jaw made by 3D printer claimed as first.

How Pot, Cocaine, and Hunger Intersect in the Brain

In June 2006 pharmaceutical giant Sanofi-Aventis began selling a new weight-loss drug called rimonabant in Europe. Rimonabant worked in part by reducing appetite, and the company claimed it could also treat addiction, harmful cholesterol, and diabetes. Lab tests even suggested the drug produced healthier sperm. But within six months, the company had received more than 900 reports of nausea, depression, and other side effects.

By the following summer, the U.S. Food and Drug Administration had rejected rimonabant, noting that relative to a placebo, patients taking it were twice as likely to contemplate, plan, or attempt suicide. The European Medicines Agency soon asked Sanofi-Aventis to address the safety concerns, and on December 5, 2008, the company pulled the drug off the European market.

Rimonabant was a spectacular flop, and yet its lure today is stronger than ever. Researchers worldwide are pursuing novel drugs aimed at the exact same target: the endocannabinoid system, an elaborate network of receptors and proteins that operate within the brain, heart, gut, liver, and throughout the central nervous system. For drug designers, the system’s powerful role in regulating cravings, mood, pain, and memory makes it a tantalizing target. The challenge now is finding sharper, more refined ways to manipulate it without causing the sort of debilitating side effects that derailed rimonabant. “The system is very, very widespread and very effective at a variety of levels,” says neuroscientist Keith Sharkey, who studies the role of endocannabinoids in the gut at the Hotchkiss Brain Institute at the University of Calgary. “It seems to be very important in the body, which is a concern when you develop drugs for it because you will get a range of effects.”

via How Pot, Cocaine, and Hunger Intersect in the Brain | Pharmaceuticals | DISCOVER Magazine.

Opinion | Investment in medical research saves lives, boosts economy

WITH the nation’s economy in poor health, the congressional “super” committee appointed to propose areas for cuts to reduce the national deficit offered the promise of a cure. But when it ended deliberations without a proposal, it provided instead a bitter pill — $1.2 trillion in mandatory across-the-board cuts, half from defense and half from domestic programs, including medical research supported by the National Institutes of Health (NIH).

For millions of Americans and their families who suffer from serious illnesses and conditions, medical research provides hope for better health. Our nation’s investment in NIH-funded medical research over the past 60 years has catalyzed many of the advances that now help Americans live longer and healthier lives.

Because of medical research, the death rate for heart disease is more than 60 percent lower — and the death rate for stroke, 70 percent lower — than in the World War II era. Cancer death rates have dropped 11.4 percent among women and 19.2 percent among men over the past 15 years because of better detection and more-effective treatments. Research related to HIV has helped increase survival for millions of people, while the average life span of an individual has never been higher.

via Opinion | Investment in medical research saves lives, boosts economy | Seattle Times Newspaper.

Chocolate cake breakfast could help you lose weight

It sounds too good to be true but new research says having dessert – along with the traditional fry up – burns off the pounds.

Morning is the best time to consume sweets because that’s when the body’s metabolism is most active – and we have the rest of the day to work off the calories, a new study shows.

Eating cookies or chocolate as part of breakfast that includes proteins and carbs also helps stem the craving for sweets later.

Researchers split 193 clinically obese, non-diabetic adults into two groups who consumed either a low-carb diet that included a 300-calorie breakfast or a balanced 600-calorie breakfast that included a chocolate cake dessert.

Halfway through the 32-week study both groups had lost an average of 33 lbs per person. But in the second half of the study the low-carb group regained an average of 22 lbs per person – while the dessert gorgers lost another 15 lbs each.

via Chocolate cake breakfast could help you lose weight – Telegraph.

Why aren’t the oldest living people getting any older? – Slate Magazine

Last month, a 114-year-old former schoolteacher from Georgia named Besse Cooper became the world’s oldest living person. Her predecessor, Brazil’s Maria Gomes Valentim, was 114 when she died. So was the oldest living person before her, and the one before her. In fact, eight of the last nine “world’s oldest” titleholders were 114 when they achieved the distinction. Here’s the morbid part: All but two were still 114 when they passed it on. Those two? They died at 115.

The celebration surrounding Cooper when she assumed the title, then, might as well have been accompanied by condolences. If historical trends hold, she will likely be dead within a year.

It’s no surprise that it’s hard to stay the “world’s oldest” for very long. These people are, after all, really old. What’s surprising is just how consistent the numbers have been. Just seven people whose ages could be fully verified by the Gerontology Research Group have ever made it past 115. Only two of those seven lived to see the 21st century. The longest-living person ever, a French woman named Jeanne Calment, died at age 122 in August 1997; no one since 2000 has come within five years of matching her longevity.

via Why aren’t the oldest living people getting any older? – Slate Magazine.

Antibiotic Fails Sinus Infection Test

Anyone who has felt the pressure of a weeklong sinus infection won’t be happy to hear it, but a study finds that a commonly prescribed medicine doesn’t clear up such attacks any better than the body does on its own.

The findings, in the Feb. 15 Journal of the American Medical Association, don’t apply to people who have chronic sinus infections lasting 28 days or more. But people with trademark signs of an acute sinus infection — yucky drainage, facial pressure, sore teeth, congestion and headache for a full week — overall fared no better with antibiotics than did people getting inert pills, scientists at Washington University in St. Louis report.

“This struck me as a very well-designed, -conducted and -analyzed study,” says James Hughes, an infectious disease physician at Emory University in Atlanta. “It adds to evidence [showing] that in most patients with acute sinus infections, antibiotics don’t add value.”

via Antibiotic Fails Sinus Infection Test – Science News.

How Interval Training Can Improve Health

While many of us wonder just how much exercise we really need in order to gain health and fitness, a group of scientists in Canada are turning that issue on its head and asking, how little exercise do we need?

The emerging and engaging answer appears to be, a lot less than most of us think — provided we’re willing to work a bit.

In proof of that idea, researchers at McMaster University in Hamilton, Ontario, recently gathered several groups of volunteers. One consisted of sedentary but generally healthy middle-aged men and women. Another was composed of middle-aged and older patients who’d been diagnosed with cardiovascular disease.

The researchers tested each volunteer’s maximum heart rate and peak power output on a stationary bicycle. In both groups, the peaks were not, frankly, very high; all of the volunteers were out of shape and, in the case of the cardiac patients, unwell. But they gamely agreed to undertake a newly devised program of cycling intervals.

via Phys Ed: How Interval Training Can Improve Health – NYTimes.com.

Freeze-tolerant Flies

Organisms that live at the frigid poles of our planet have evolved strategies to withstand temperatures that would kill most species instantly. Some secrete ice-nucleating substances that control the freezing process, for example, while others accumulate anti-freeze proteins that allow their cells to remain unfrozen even at subzero temperatures, a phenomenon known as supercooling. Now, researchers in the Czech Republic have shown that some of these strategies can be conferred upon species that would otherwise succumb to the cold, like the temperate-adapted Drosophila melanogaster.

The results, published today (February 13) in the Proceedings of the National Academy of Sciences, could have implications for tissue storage and cryopreservation strategies for more complex organisms.

“It’s an amazing paper,” said Ben Philip, a physiologist ecologist at Rivier College in New Hampshire, who was not involved in the research. “We previously considered organisms to fall into one of two groups—freeze tolerant or intolerant. The study’s novelty comes from being able to make the intolerant tolerant.”

Drosophila melanogaster. Wikimedia Commons, André Karwath

via Freeze-tolerant Flies | The Scientist.

Successful human tests for first wirelessly controlled drug-delivery chip

About 15 years ago, MIT professors Robert Langer and Michael Cima had the idea to develop a programmable, wirelessly controlled microchip that would deliver drugs after implantation in a patient’s body. This week, the MIT researchers and scientists from MicroCHIPS Inc. reported that they have successfully used such a chip to administer daily doses of an osteoporosis drug normally given by injection.

The results, published in the Feb. 16 online edition of Science Translational Medicine, represent the first successful test of such a device and could help usher in a new era of telemedicine — delivering health care over a distance, Langer says.

via Successful human tests for first wirelessly controlled drug-delivery chip – MIT News Office.

Printing Muscle

In a small clean room tucked into the back of San Diego–based startup Organovo, Chirag Khatiwala is building a thin layer of human skeletal muscle. He inserts a cartridge of specially prepared muscle cells into a 3-D printer, which then deposits them in uniform, closely spaced lines in a petri dish. This arrangement allows the cells to grow and interact until they form working muscle tissue that is nearly indistinguishable from something removed from a human subject.

The technology could fill a critical need. Many potential drugs that seem promising when tested in cell cultures or animals fail in clinical trials because cultures and animals are very different from human tissue. Because Organovo’s product is so similar to human tissue, it could help researchers identify drugs that will fail long before they reach clinical trials, potentially saving drug companies billions of dollars. So far, Organovo has built tissue of several types, including cardiac muscle, lung, and blood vessels.

Unlike some experimental approaches that have used ink-jet printers to deposit cells, Organovo’s technology enables cells to interact with each other much the way they do in the body. They are packed tightly together and incubated, prompting them to adhere to each other and trade chemical signals. When they’re printed, the cells are kept bunched together in a paste that helps them grow, migrate, and align themselves properly. ­Muscle cells, for example, orient themselves in the same direction to create tissue that can contract.

via Printing Muscle – Technology Review.

Disease-Fighting Secrets of Genetically Modified Mosquitoes

Insects cover our planet. Filed into 750,000 different species, at any given time there are one million trillion bugs buzzing around the globe.

About 14,000 of those species are blood-feeders, meaning they drink their meals by puncturing the skin of vertebrates, including humans. Besides being a nuisance, blood-feeding insects, such as certain strains of mosquitoes, are infected with parasitic organisms that are no threat to the bugs themselves, but if transferred to humans, become toxic, or worse, lethal.

A new collection of studies from PLoS charts alternative strategies for curbing mosquito-borne diseases such as dengue and malaria using genetically modified insects. The idea is to create mosquitoes that are less infectious and pass their altered genetics to the next generation by breeding with their natural counterparts.

Aedes aegyptivia Disease-Fighting Secrets of Genetically Modified Mosquitoes | Wired Science | Wired.com.

‘I Wanted To Live’: New Depression Drugs Offer Hope For Toughest Cases

A club drug called “Special K” is generating a lot of buzz among researchers who study depression.

That’s because “Special K,” which is actually an FDA-approved anesthetic named ketamine, can relieve even suicidal depression in a matter of hours. And it works on many patients who haven’t responded to current antidepressants like Prozac.

Those traditional drugs, which act on the brain’s serotonin system, can take more than a month to kick in, and don’t work for up to 40 percent of people with major depression.

“We can take care of a migraine in hours,” says Carlos Zarate, a brain researcher at the National Institute of Mental Health who is studying ketamine. “So why do we have to wait weeks or months with depression?”

Ketamine itself isn’t likely to become the next big drug for depression because it has troubling side effects, including hallucinations, Zarate says. But understanding how ketamine works could lead to safer drugs that are just as effective, he says.

via ‘I Wanted To Live’: New Depression Drugs Offer Hope For Toughest Cases : Shots – Health Blog : NPR.

Toying with biological systems

Bacteria don’t normally take photographs. Nor do they attack tumor cells or produce chemicals. But with some help from biological engineer Chris Voigt, they can do all that and more.

Voigt, who joined MIT’s faculty in July as an associate professor of biological engineering, likes to tinker with bacteria and other microbes to get them to perform myriad useful tasks that nature never intended — an approach known as synthetic biology.

For example, to develop their “bacterial camera,” Voigt and his students inserted a light-detecting sensor from an alga into the bacterium E. coli, coupled with a gene that causes the bacterium to make a black pigment. A sheet of these bacteria acts as the “film,” and when a stencil is laid over the film and light shone upon it, an image of the stencil forms on the sheet of bacteria.

Likewise, his tumor-targeting E. coli incorporate genes from other bacteria that detect low oxygen levels and high cell density, both conditions often found in tumors. Voigt, who had been on the faculty of the University of California at San Francisco before coming to MIT, then linked those genes with a cell circuit that triggers production of a protein called invasin that enables E. coli to invade mammalian cells.

via Toying with biological systems – MIT News Office.

Aging of Eyes Is Blamed in Circadian Rhythm Disturbances

For decades, scientists have looked for explanations as to why certain conditions occur with age, among them memory loss, slower reaction time, insomnia and even depression. They have scrupulously investigated such suspects as high cholesterol, obesity, heart disease and an inactive lifestyle.

Now a fascinating body of research supports a largely unrecognized culprit: the aging of the eye.

The gradual yellowing of the lens and the narrowing of the pupil that occur with age disturb the body’s circadian rhythm, contributing to a range of health problems, these studies suggest. As the eyes age, less and less sunlight gets through the lens to reach key cells in the retina that regulate the body’s circadian rhythm, its internal clock.

via Aging of Eyes Is Blamed in Circadian Rhythm Disturbances – NYTimes.com.

Russian scientists regenerate ice age plant

It was an ice age squirrel’s treasure chamber, a burrow containing fruit and seeds that had been stuck in the Siberian permafrost for over 30,000 years. From the fruit tissues, a team of Russian scientists managed to resurrect an entire plant in a pioneering experiment that paves the way for the revival of other species.

The Silene stenophylla is the oldest plant to be regenerated, the researchers said, and it is fertile, producing white flowers and viable seeds.

The experiment proves that permafrost serves as a natural depository for ancient life forms, said the Russian researchers, who published their findings in Tuesday’s issue of Proceedings of the National Academy of Sciences of the UnitedStates.

Silene stenophylla

via Russian scientists regenerate ice age plant | World news | The Guardian.

Sirtuin protein linked to longevity in mammals

At last, a member of the celebrated sirtuin family of proteins has been shown to extend lifespan in mammals — although it’s not the one that has received the most attention and financial investment.

Sirtuin genes and the proteins they encode have intrigued many researchers who study ageing ever since they were first linked to longevity in yeast. Results published today in Nature suggest that the overexpression of one gene, called sirtuin 6 (SIRT6), can lengthen lifespan in male mice by as much as 15.8%

Male mice with boosted levels of the sirtuin protein SIRT6 could live longer.

GETTY IMAGES

via Sirtuin protein linked to longevity in mammals : Nature News & Comment.

The Patient of the Future

Back in 2000, when Larry Smarr left his job as head of a celebrated supercomputer center in Illinois to start a new institute at the University of California, San Diego, and the University of California, Irvine, he rarely paid attention to his bathroom scale. He regularly drank Coke, added sugar to his coffee, and enjoyed Big Mac Combo Meals with his kids at McDonald’s. Exercise consisted of an occasional hike or a ride on a stationary bike. “In Illinois they said, ‘We know what’s going to happen when you go out to California. You’re going to start eating organic food and get a blonde trainer and get a hot tub,’ ” recalls Smarr, who laughed off the predictions. “Of course, I did all three.”

Smarr, who directs the California Institute for Telecommunications and Information Technology in La Jolla, dropped from 205 to 184 pounds and is now a fit 63-year-old. But his transformation transcends his regular exercise program and carefully managed diet: he has become a poster man for the medical strategy of the future. Over the past decade, he has gathered as much data as he can about his body and then used that information to improve his health. And he has accomplished something that few people at the forefront of the “quantified self” movement have had the opportunity to do: he helped diagnose the emergence of a chronic disease in his body.

via The Patient of the Future – Technology Review.