Supreme Court declines to hear new contraception cases
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The U.S. Supreme Court on Monday declined to take up preliminary appeals brought by Roman Catholic groups that want an exemption from part of President Barack Obama’s healthcare law requiring employers to provide insurance that covers contraception.
The cases were brought by a series of Roman Catholic-affiliated nonprofit groups based in Washington, D.C., including Catholic University.
The legal issue is different from one involving for-profit companies that also object on religious grounds to the so-called contraception mandate, which was argued before the high court last week.
The Supreme Court’s decision not to hear the two cases at this stage means that the federal appeals court in Washington will proceed to decide the issue. If the groups lose, they would have another chance to seek Supreme Court review.
Tamiflu-resistant influenza: Parsing the genome for the culprits
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Tamiflu is one of the few available treatments for those who come down with the flu. But the virus quickly develops resistance; multiplying at a rate of several generations a day, these tiny pathogens rapidly accumulate genetic mutations. Because of this, they have a good chance of developing counterattacks to the antiviral. How can these infinitesimal variations be identified within the immensity of the virus’ genetic code? EPFL researchers have created a computer tool that can shed light on the flu virus’ formidable adaptability. They were able to find mutations that conferred resistance that had up to this point not yet been identified. Their software has been made freely available to researchers everywhere, and is the subject of an article published in the journal PLOS Genetics.
Widespread use of Tamiflu leads to resistance
In theory, Tamiflu should only be used by patients in fragile health. But during the 2008-2009 flu season, the drug was used for the first time on a very wide scale. Resistant strains of the virus appeared within just a few weeks. Fortunately, even though the mutation induced a resistance to Tamiflu, it also caused a reduction in the replication rate of the virus. Once the use of the antiviral was dialed back to a more reasonable level, the resistant strains lost their competitive advantage, and they disappeared, submerged by competitors that were sensitive to the drug but had a higher rate of replication.
Resistance always results from random mutations, says Jeffrey Jensen, co-author of the EPFL study. But when a mutation leads to a competitive advantage, for example the ability to resist against a source of aggression, it tends to be passed on to its descendants. “A priori, nothing distinguishes one mutation from another; they’re all the result of chance. Our goal is precisely to be able to tell the difference between mutations that make the virus resistant to Tamiflu, thus leading to a selection phenomenon, and other mutations.”
Optimism linked to healthier eating among women
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Women with a sunny disposition may also have an easier time adopting healthy habits, according to a new study.
Researchers found that women who were more optimistic were better able to follow healthy eating guidelines, both when they were instructed to do so and when they chose to make changes on their own.
The authors noted that the biggest help for making diet improvements is not necessarily optimism itself, but the skills that tend to go with it.
“It’s not just having a sunny outlook - rather, this is a marker of other things people do,” said Melanie Hingle, a dietician at the University of Arizona in Tucson. She led the new study, which was published in the Journal of the Academy of Nutrition and Dietetics.
U.S. advisers back DNA-based colon cancer test
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A colon cancer screening method that analyzes DNA from stool samples won the unanimous backing of a U.S. advisory panel on Thursday, paving the way for potential regulatory approval of the non-invasive test.
A panel of outside experts advising the Food and Drug Administration voted 10-0 to recommend approval of the Cologuard screening test made by Exact Sciences Corp.
The company said a large clinical trial found that its test detected 92.3 percent of colorectal cancers in average-risk patients based on a combination of DNA and hemoglobin markers.
While a colonoscopy is considered the most accurate method of detecting colon cancer and polyps, many people avoid the test, which involves inserting a flexible tube into the colon.
Pfizer lung cancer drug beats chemo for previously untreated patients
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Pfizer Inc’s Xalkori delayed progression of lung cancer longer than chemotherapy in patients who had never previously been treated for the disease, according to results of a late-stage study released on Tuesday.
The medicine, which received U.S. approval in 2011 for lung cancer patients who have a specific gene mutation, had shown in a previous Phase III trial that it significantly delayed disease progression among those who have already undergone chemotherapy for non-small-cell lung cancer, the most common form of the illness.
Pfizer said favorable results from the latest trial, combined with those from the earlier big study, establish that Xalkori is appropriate for first-line as well as second-line use, meaning for patients receiving initial treatment as well as for those who have already undergone chemotherapy.
Mass. General study identifies path to safer drugs for heart disease, cancer
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Massachusetts General Hospital (MGH) investigators may have found a way to solve a problem that has plagued a group of drugs called ligand-mimicking integrin inhibitors, which have the potential to treat conditions ranging from heart attacks to cancer metastasis. In a Nature Structural & Molecular Biology paper receiving advance online publication, the researchers provide a structural basis for the design of new and safer integrin inhibitors.
Integrins are receptor proteins found on the surface of cells that determine whether or not cells adhere to adjacent cells and the surrounding extracellular matrix. Under normal circumstances, integrins only become activated - which allows them to bind to other cells or extracellular molecules - in response to specific signals from within the cell. If integrins become overactive, cells become too “sticky” - leading to clogged arteries, pathological inflammation, the excess tissue growth called fibrosis or the spread of cancer. Current drugs developed to inhibit integrin activation by mimicking the shape of ligands - the molecules that interact with receptors - have had unintended effects in some patients, and as a result only a handful have received FDA approval.
“Integrins have an intrinsic ability to shape-shift when they switch from an inactive to an active, adhesive state,” explains M. Amin Arnaout, MD, director of the MGH Leukocyte Biology Program and the Inflammation and Structural Biology Program, senior author of the study. “Unfortunately, under some circumstances the integrin inhibitors that have been developed to date can inadventently induce this shape shifting, and use of these drugs have produced serious, sometimes fatal side effects such as excessive bleeding.”
Gates Foundation awards Notre Dame $23 million for malaria, dengue studies
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The Bill & Melinda Gates Foundation has awarded $23 million for research being led by University of Notre Dame biologists to prevent malaria and dengue fever, the school said.
The five-year project by biologists Neil Lobo and Nicole Achee aims to show the effectiveness of a new method of mosquito control, called spatial repellency, in quelling the illnesses, the university said in a statement this week.
According to the World Health Organization, 207 million cases of malaria were reported in 2012, and 50 million to 100 million dengue infections occur yearly.
Both the malaria parasite and dengue virus are transmitted through the bites of infected mosquitoes. Spatial repellents, such as coils or candles, release a material that drives mosquitoes away from enclosed areas.
More dangerous chemicals in everyday life: Now experts warn against nanosilver
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Endocrine disrupters are not the only worrying chemicals that ordinary consumers are exposed to in everyday life. Also nanoparticles of silver, found in e.g. dietary supplements, cosmetics and food packaging, now worry scientists. A new study from the University of Southern Denmark shows that nano-silver can penetrate our cells and cause damage.
Silver has an antibacterial effect and therefore the food and cosmetic industry often coat their products with silver nanoparticles. Nano-silver can be found in e.g. drinking bottles, cosmetics, band aids, toothbrushes, running socks, refrigerators, washing machines and food packagings.
“Silver as a metal does not pose any danger, but when you break it down to nano-sizes, the particles become small enough to penetrate a cell wall. If nano-silver enters a human cell, it can cause changes in the cell”, explain Associate Professor Frank Kjeldsen and PhD Thiago Verano-Braga, Department of Biochemistry and Molecular Biology at the University of Southern Denmark.
Bisphenol A (BPA) at Very Low Levels Can Adversely Affect Developing Organs in Primates, MU Researcher Finds
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Bisphenol A (BPA) is a chemical that is used in a wide variety of consumer products, such as resins used to line metal food and beverage containers, thermal paper store receipts, and dental composites. BPA exhibits hormone-like properties, and exposure of fetuses, infants, children or adults to the chemical has been shown to cause numerous abnormalities, including cancer, as well as reproductive, immune and brain-behavior problems in rodents. Now, researchers at the University of Missouri have determined that daily exposure to very low concentrations of BPA by pregnant females also can cause fetal abnormalities in primates.
“BPA is an endocrine disrupting chemical that has been demonstrated to alter signaling mechanisms involving estrogen, androgen and thyroid hormones,” said Frederick vom Saal, Curators Professor of Biological Sciences in the College of Arts and Science at MU. “Previous studies in rodents have demonstrated that maternal exposure to very low doses of BPA can significantly alter fetal development, resulting in a variety of adverse outcomes in the fetus. Our study is one of the first to show this also happens in primates.”
Although BPA is considered a toxic chemical in other countries such as Canada, the U.S. has been slow to address the issue, said vom Saal. Until now, most studies involving BPA have been conducted on laboratory mice and rats, leading U.S. regulatory agencies to call for studies in primates. With funding provided by the National Institute of Environmental Health Sciences (NIEHS), a research institute of the National Institutes of Health, vom Saal and his colleagues studied the chemical’s blood levels in pregnant female rhesus monkeys and their fetuses, which are considered to be very similar to human fetuses.
Study Reveals Evolution at Work
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New research by UC Santa Barbara’s Kenneth S. Kosik, Harriman Professor of Neuroscience, reveals some very unique evolutionary innovations in the primate brain.
In a study published online today in the journal Neuron, Kosik and colleagues describe the role of microRNAs - so named because they contain only 22 nucleotides - in a portion of the brain called the outer subventricular zone (OSVZ). These microRNAs belong to a special category of noncoding genes, which prevent the formation of proteins.
“It’s microRNAs that provide the wiring diagram, dictating which genes are turned on, when they’re turned on and where they’re turned on,” said Kosik, who is also the co-director of UCSB’s Neuroscience Research Institute and a professor in the Department of Molecular, Cellular and Developmental Biology. “There’s a core set with which all kinds of really complex things can be built, and these noncoding genes know how to put it together.”
Vinegar kills tuberculosis and other mycobacteria
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The active ingredient in vinegar, acetic acid, can effectively kill mycobacteria, even highly drug-resistant Mycobacterium tuberculosis, an international team of researchers from Venezuela, France, and the US reports in mBio®, the online open-access journal of the American Society for Microbiology.
Acetic acid might be used as an inexpensive and non-toxic disinfectant against drug-resistant tuberculosis (TB) bacteria as well as other stubborn, disinfectant-resistant mycobacteria.
Work with drug-resistant tuberculosis bacteria carries serious biohazard risks. Chlorine bleach is often used to disinfect TB cultures and clinical samples, but bleach is toxic and corrosive. Other effective commercial disinfectants can be too expensive for TB labs in the resource-poor countries where the majority of TB occurs.
“Mycobacteria are known to cause tuberculosis and leprosy, but non-TB mycobacteria are common in the environment, even in tap water, and are resistant to commonly used disinfectants. When they contaminate the sites of surgery or cosmetic procedures, they cause serious infections. Innately resistant to most antibiotics, they require months of therapy and can leave deforming scars.” says Howard Takiff, senior author on the study and head of the Laboratory of Molecular Genetics at the Venezuelan Institute of Scientific Investigation (IVIC) in Caracas.
Study in fruitflies strengthens connection among protein misfolding, sleep loss, and age
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Pulling an “all-nighter” before a big test is practically a rite of passage in college. Usually, it’s no problem: You stay up all night, take the test, and then crash, rapidly catching up on lost sleep. But as we age, sleep patterns change, and our ability to recoup lost sleep diminishes.
Researchers at the Perelman School of Medicine, University of Pennsylvania, have been studying the molecular mechanisms underpinning sleep. Now they report that the pathways of aging and sleep intersect at the circuitry of a cellular stress response pathway, and that by tinkering with those connections, it may be possible to alter sleep patterns in the aged for the better - at least in fruit flies.
Nirinjini Naidoo, PhD, associate professor in the Center for Sleep and Circadian Neurobiology and the Division of Sleep Medicine, led the study with postdoctoral fellow Marishka Brown, PhD, which was published online before print in the journal Neurobiology of Aging.
Increasing age is well known to disrupt sleep patterns in all sorts of ways. Elderly people sleep at night less than their younger counterparts and also sleep less well. Older individuals also tend to nap more during the day. Naidoo’s lab previously reported that aging is associated with increasing levels of protein unfolding, a hallmark of cellular stress called the “unfolded protein response.”
Study reveals workings of working memory
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Keep this in mind: Scientists say they’ve learned how your brain plucks information out of working memory when you decide to act.
Say you’re a busy mom trying to wrap up a work call now that you’ve arrived home. While you converse on your Bluetooth headset, one kid begs for an unspecified snack, another asks where his homework project has gone, and just then an urgent e-mail from your boss buzzes the phone in your purse. During the call’s last few minutes these urgent requests - snack, homework, boss - wait in your working memory. When you hang up, you’ll pick one and act.
When you do that, according to Brown University psychology researchers whose findings appear in the journal Neuron, you’ll employ brain circuitry that links a specific chunk of the striatum called the caudate and a chunk of the prefrontal cortex centered on the dorsal anterior premotor cortex. Selecting from working memory, it turns out, uses similar circuits to those involved in planning motion.
In lab experiments with 22 adult volunteers, the researchers used magnetic resonance imaging to track brain activity during a carefully designed working memory task. They also measured how quickly the subjects could choose from working memory - a phenomenon the scientists called “output gating.”
An essential step toward printing living tissues
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A new bioprinting method developed at the Wyss Institute for Biologically Inspired Engineering at Harvard University and the Harvard School of Engineering and Applied Sciences (SEAS) creates intricately patterned 3D tissue constructs with multiple types of cells and tiny blood vessels. The work represents a major step toward a longstanding goal of tissue engineers: creating human tissue constructs realistic enough to test drug safety and effectiveness.
The method also represents an early but important step toward building fully functional replacements for injured or diseased tissue that can be designed from CAT scan data using computer-aided design (CAD), printed in 3D at the push of a button, and used by surgeons to repair or replace damaged tissue.
“This is the foundational step toward creating 3D living tissue,” said Jennifer Lewis, Ph.D., senior author of the study, who is a Core Faculty Member of the Wyss Institute for Biologically Inspired Engineering at Harvard University, and the Hansjörg Wyss Professor of Biologically Inspired Engineering at Harvard SEAS. Along with lead author David Kolesky, a graduate student in SEAS and the Wyss Institute, her team reported the results February 18 in the journal Advanced Materials.
Tissue engineers have tried for years to produce lab-grown vascularized human tissues robust enough to serve as replacements for damaged human tissue. Others have printed human tissue before, but they have been limited to thin slices of tissue about a third as thick as a dime. When scientists try to print thicker layers of tissue, cells on the interior starve for oxygen and nutrients, and have no good way of removing carbon dioxide and other waste. So they suffocate and die.
Family problems experienced in childhood and adolescence affect brain development
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The study led by Dr Nicholas Walsh, lecturer in developmental psychology at the University of East Anglia, used brain imaging technology to scan teenagers aged 17-19. It found that those who experienced mild to moderate family difficulties between birth and 11 years of age had developed a smaller cerebellum, an area of the brain associated with skill learning, stress regulation and sensory-motor control. The researchers also suggest that a smaller cerebellum may be a risk indicator of psychiatric disease later in life, as it is consistently found to be smaller in virtually all psychiatric illnesses.
Previous studies have focused on the effects of severe neglect, abuse and maltreatment in childhood on brain development. However the aim of this research was to determine the impact, in currently healthy teenagers, of exposure to more common but relatively chronic forms of ‘family-focused’ problems. These could include significant arguments or tension between parents, physical or emotional abuse, lack of affection or communication between family members, and events which had a practical impact on daily family life and might have resulted in health, housing or school problems.
Dr Walsh, from UEA’s School of Psychology, said: “These findings are important because exposure to adversities in childhood and adolescence is the biggest risk factor for later psychiatric disease. Also, psychiatric illnesses are a huge public health problem and the biggest cause of disability in the world.
