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So, is a moderate level of drinking good for you, or not?
Apparently, encouraged by reports that alcohol reduces your risk of heart attack, some researchers are conducting a clinical trial to chart the effects of ‘prescribing’ a drink a day. Mark Willenbring, the former director of the Treatment and Recovery Research Division of the National Institute on Alcohol Abuse and Alcoholism, gives some ‘straight talk’ on this issue to the New York Times. His answer is very reasoned and nuanced and caviat-y, but here’s what I see as the (important!) bottom line:
“My personal take on all this is that for most people, low-risk drinking is not harmful to health — and may be helpful.”
Canines and humans get many of the same diseases, and often respond to the same drug treatments. Dogs also tend to mimic the symptoms and pathology of human disease much more closely than rodents do.
“Understanding the underlying genetics in dogs is almost certain to enlighten us about the human condition,” notes Elaine Ostrander, chief of the Cancer Genetics Branch at the National Human Genome Research Institute.
Because dogs are purposely inbred for specific traits and are extremely well characterized, scientists have long used their pedigrees to study cancer and other biological diseases. But researchers are just beginning to use dogs as models of psychiatric and behavioral conditions, including obsessive-compulsive disorder (OCD) and autism.
In a January report, for instance, scientists pinpointed a genetic hotspot for compulsive behavior by screening a conspicuous subgroup of Doberman Pinschers: those that repetitively suck their flanks. The findings were published in Biological Psychiatry.
The gene may also drive compulsive behaviors in other dog breeds and other species, the researchers say.
“We think this gene will also be the same one involved in human OCD,” notes investigator Nicholas Dodman, director of the animal behavior clinic at Tufts University in Massachusetts. “This is really just the beginning of using [dog] behaviors to study behaviors of humans.”
A class of medications widely used during pregnancy to treat asthma and prevent early labor increases the baby’s risk of autism and other psychiatric disorders, according to a controversial review in the American Journal of Obstetrics and Gynecology.
The review, published in the journal’s December issue, proposes that long-term exposure to the drugs — called beta-2 adrenergic (B2A) agonists — during key periods of brain development can send the nervous system into overdrive, eventually giving rise to autism.
Because of these risks, the drugs should only be used in extreme circumstances, such as for acute asthma attacks or for staving off labor for less than 72 hours, the authors warn.
Some experts are unhappy about the review, noting that it is based primarily on data from animal work. Only three human studies have looked at the drugs’ direct association with autism: one small twin study, one case report and preliminary data from an unpublished epidemiological study.
You may think the simplest explanation is economics. And it’s true that, compared with white families, Hispanic families are less likely to have health insurance and a regular doctor, and more likely to fall below the poverty line.
But the autism disparity remains even when researchers account for those socioeconomic differences, according to a study out this month in the American Journal of Public Health.
Made a batch of these adorable and delicious cookies yesterday. The recipe is quite easy, but it does take a lot of time to finish. I kept thinking how fun it would be to have a 8-year-old around to help. Full instructions (courtesy of Food Network) and more photos below the fold.
The deletion, known briefly as 16p, covers a 25-gene stretch of chromosomal region 16p11.2. It crops up in roughly 0.6 percent of all cases of autism. Some studies have found the variant in individuals with other psychiatric conditions, such as schizophrenia and bipolar disorder, and even in healthy controls.
The new reports are the first to search for obesity-related rare variants across the genome and the first to link 16p — or any other rare DNA deletion or duplication — to obesity.
“The contribution of [rare variants] to obesity, just like for autism and schizophrenia, may be much more important than has been anticipated thus far,” says Jacques Beckmann, chair of medical genetics at University of Lausanne in Switzerland, and lead investigator of one of the new studies. “We should not ignore it.”
One of the studies also finds, for the first time, that oxytocin regulation in people with autism is partly controlled by epigenetic changes, which can turn genes on or off without altering the underlying code.
Oxytocin has been linked to autism for nearly two decades, and the hormone is already being doled out in several small clinical trials to treat the disorder. But the new reports are part of a growing wave of interest in the precise nature of its involvement.
“The field is really new,” says Sue Carter, professor of psychiatry at University of Illinois at Chicago, who was not involved in either new study.
Researchers have previously found significant associations between particular oxytocin-related variants and autism, but how these variants alter the hormone’s production or interact with other genes and developmental influences is unclear, Carter says. “At this point, we’re working with fragments of knowledge, but the fragments we have are remarkably consistent.”
The close-ups are so striking, they made the cover of the 11 January Journal of Cell Biology.
To capture this pretty picture, the researchers used a complex technique called electron cryotomography. They first froze rat brain cells in action at temperatures as low as -165 degrees Celsius, then looked at the cells at different angles using an electron microscope and, finally, reconstructed them in three dimensions on a computer.
There are other methods to look at synapses, but they require cells to be fixed in chemicals for a long time, which can distort the final product. Light microscopy, a much older and more popular technique, illuminates living cells, but only down to 400 nanometers.
Electron cryotomography seems to beat all of these: its flash-freezing preserves the cell’s structure, and its resolution is 5 nanometers — the size of a few dozen atoms.
The technique reveals the workings of some of the tiny protein filaments scattered across a synapse, whose role had been largely unknown before. One type of filament, dubbed ‘tethers’, anchors synaptic vesicles — the bubble-like structures that shuttle chemical messengers inside the cell — to the cell membrane. That way, when the cell receives the appropriate electric signal, the vesicles are in the right position to release the chemicals into the synapse.
