Most of the more than 6,000 species of frogs in the world lay their eggs in water. But many tropical frogs lay their eggs out of water. This behavior protects the eggs from aquatic predators, such as fish and tadpoles, but also increases their risk of drying out. Justin Touchon, post-doctoral fellow at the Smithsonian Tropical Research Institute, discovered that climate change in Panama may be altering frogs' course of evolution. By analyzing long-term rainfall data collected by the Panama Canal Authority, Touchon discovered that rainfall patterns are changing just as ...

A large-scale study that defines the complexity of underlying mutations responsible for pancreatic cancers in more than 100 patients was published in Nature today. The analysis represents the first report from Australia's contribution to the International Cancer Genome Consortium (ICGC), which brings together the world's leading scientists to identify the genetic drivers behind 50 different cancer types. Pancreatic cancer has the highest mortality rate of all the major cancers and is one of the few for which survival has not improved substantially over the past 40 ...

Researchers at the National Heart Centre Singapore (NHCS) have successfully created a human heart cell model of arrhythmogenic right ventricular cardiomyopathy (ARVC), an inherited heart muscle disorder which puts one at high risk of developing life-threatening arrhythmias and sudden cardiac death. The NHCS research team discovered that key characteristics of the disease, such as abnormal "fatty changes" and altered distribution of proteins involved in cell-cell connections (called desmosomal proteins) are reproduced in the heart cells. This novel cellular model for studying ...

On July 20, a gunman in Aurora, Colorado, used an assault rifle to murder 12 people and wound 58 others. Although this was one of the worst mass shootings in U.S. history, all mass shootings account for a small percentage of gun violence that occurs in the U.S. every day. In the past 100 days since the Aurora shooting, an estimated 3,035 Americans have died as a result of gun violence. A new report by researchers at the Johns Hopkins Bloomberg School of Public Health examines policies and initiatives for reducing gun violence in the U.S. by reforming current gun policies. ...

DURHAM, N.C. – While studying the sense of touch, scientists at Duke Medicine have pinpointed specific neurons that appear to regulate perception. The sensory neurons are characterized by thin spikes, and based on their volume, these protrusions determine the cells' sensitivity to force. The findings in fruit fly larvae, which appear in online Oct. 25, 2012, in the journal Current Biology, demonstrate the first known function for the sensory neurons and provide insights that could broaden the understanding of chronic pain syndromes in humans. "On a molecular level, ...

PHILADELPHIA - Most healthy cells rely on a complicated process to produce the fuel ATP. Knowing how ATP is produced by the cell's energy storehouse – the mitochondria -- is important for understanding a cell's normal state, as well as what happens when things go wrong, for example in cancer, cardiovascular disease, neurodegeneration, and many rare disorders of the mitochondria. Two years ago, Kevin Foskett, PhD, professor of Physiology at the Perelman School of Medicine, University of Pennsylvania, and colleagues discovered that fundamental control of ATP is an ongoing ...

Severe spermatogenic failure (SSF) is a genetic condition that causes low sperm count and infertility. New insights into the genetic alterations that cause this disorder and their prevalence in populations of men around the world are provided by a study published by Cell Press in the American Journal of Human Genetics on October 25. The findings reveal which alterations are the greatest risk factors for the disease, and they could be immediately applicable in genetic counseling for assisted reproduction. "Medically relevant population genetics studies are well established ...

When patients are put under anesthesia, they are often told they will be "put to sleep," and now it appears that in some ways that's exactly what the drugs do to the brain. New evidence in mice reported online on October 25 in Current Biology, a Cell Press publication, shows that the drugs don't just turn wakefulness "off," they also force important sleep circuits in the brain "on." "Despite more than 160 years of continuous use in humans, we still do not understand how anesthetic drugs work to produce the state of general anesthesia," said Max Kelz of the University ...

STANFORD, Calif. — Coaxing a humble skin cell to become a jack-of-all-trades pluripotent stem cell is feat so remarkable it was honored earlier this month with the Nobel Prize in Physiology or Medicine. Stem cell pioneer Shinya Yamanaka, MD, PhD, showed that using a virus to add just four genes to the skin cell allowed it to become pluripotent, or able to achieve many different developmental fates. But researchers and clinicians have been cautious about promoting potential therapeutic uses for these cells because the insertion of the genes could render the cells cancerous. Now ...

ANN ARBOR— The genes responsible for inherited diseases are clearly bad for us, so why hasn't evolution, over time, weeded them out and eliminated them from the human genome altogether? Part of the reason seems to be that genes that can harm us at one stage of our lives are necessary and beneficial to us at other points in our development. The idea that the same gene can be both beneficial and harmful, depending on the situation, is called antagonistic pleiotropy. The theory has been around since the 1950s and has been used to explain aging, cancer and genetic diseases. But ...

DETROIT – Patients treated with an epidural steroid injection for back pain relief are at increased risk of bone fractures in the spine, according to a Henry Ford Hospital study. Researchers say the risk of fracture increased 29 percent with each steroid injection, a finding they believe raises patient safety concerns. "For a patient population already at risk for bone fractures, steroid injections carry a greater risk that previously thought and actually pose a hazard to the bone," says Shlomo Mandel, M.D., a Henry Ford orthopedic physician and the study's lead author. Dr. ...

When a female mates with several males, these will compete over the fertilization her eggs. This is an important evolutionary force that has led to the evolution of a diversity of male sexual organ morphologies. This is revealed in a study of seed beetles published today in the leading scientific journal Current Biology. In higher plants, the influential classification system developed by Carl von Linnaeus relied on the fact that the reproductive parts of plants are evolutionarily stable. This is in sharp contrast to the reproductive organs of animals with internal fertilization, ...

(Philadelphia, PA) – Researchers at Temple University's Center for Translational Medicine and the University of Pennsylvania have identified a protein that serves as a gatekeeper for controlling the rush of calcium into the cell's power source, the mitochondria. Without this calcium spigot under control, calcium levels can run amok, contributing to cardiovascular disease, diabetes and neurodegeneration. The findings, reported online October 25, 2012, in the journal Cell, add important new insights into the inner workings of the mitochondria and may eventually help scientists ...

The first mouse model of the common bacterial disease typhoid fever is reported in a study published by Cell Press October 25 in the journal Cell. Because the animals show human-like symptoms and respond positively to immunization, they could be used to develop more effective vaccines against the deadly pathogen. "Prior to our work, there was no small animal model for studying immune responses to the bacteria that cause typhoid fever," says study author Matthew Hayden of Columbia University. "We hope that the model we have developed will promote rapid progress in developing ...

Researchers at Johns Hopkins have figured out the three-dimensional shape of the protein responsible for creating unique bonds within the cell wall of the bacteria that cause tuberculosis. The bonds make the bacteria resistant to currently available drug therapies, contributing to the alarming rise of these super-bacteria throughout the world. With the protein structure in hand, the scientists say, drug designers have a clear way forward for weakening the cell wall and killing these deadly bacteria. Their results are reported in a paper published online Oct. 25 in Structure. "We've ...

New York, NY (October 25, 2012) — Columbia University Medical Center (CUMC) researchers have created the first true mouse model of typhoid infection. The development promises to advance the study of typhoid and the creation of new vaccines against the infection, which remains a major health threat in developing countries. The paper was published today in the online edition of the journal Cell. "Vaccines are the most practical solution for preventing typhoid in the Third World. Unfortunately, existing typhoid vaccines are only modestly effective, leaving millions of people ...

Resveratrol, an ingredient in red wine thought to improve insulin sensitivity, reduce risk of heart disease and increase longevity, does not appear to offer these benefits in healthy women, new research at Washington University School of Medicine in St. Louis indicates. The study, reported online Oct. 25 in Cell Metabolism, involved 29 post-menopausal women who did not have type 2 diabetes and who were reasonably healthy. For 12 weeks, half took an over-the-counter resveratrol supplement, and the rest got a placebo, or sugar pill. "Resveratrol supplements have become ...

Powerful antibiotics that scientists and physicians thought stop the growth of harmful bacteria by completely blocking their ability to make proteins actually allow the germs to continue producing certain proteins -- which may help do them in. The finding, by a team at the University of Illinois at Chicago College of Pharmacy, clarifies how antibiotics work and may aid in the discovery of new drugs or improve clinical therapy with existing ones. The study is published in the Oct. 26 issue of the journal Cell. Among the most complex molecular machines in the cell are ...

CAMBRIDGE, Mass. (October 25, 2012) — A large-scale analysis of Y chromosomes from more than 20,000 men finds that two spontaneously recurring deletions along a complex region of the Y chromosome are responsible for approximately 8% of cases of failed sperm production. Although previous research had identified deletions in the region of the Y known as AZFc (for azoospermia factor c) as causing severe spermatogenic failure (SSF), this latest analysis, conducted by Whitehead Institute Director David Page and colleagues, is the first to determine how prevalent these deletions ...

(Edmonton) The Biggest Loser might be a TV ratings winner, but its extreme depiction of exercise is more likely to turn people off than get them off the couch, according to new research from the University of Alberta. Researchers in the Faculty of Physical Education and Recreation found that watching a short video clip of the Biggest Loser fuelled negative attitudes toward exercise, raising further questions about how physical activity is shown in the popular media. "The depictions of exercise on shows like The Biggest Loser are really negative," said lead author Tanya ...

Genetics researchers at the University of Adelaide have solved a 40-year mystery for a family beset by a rare intellectual disability – and they've discovered something new about the causes of intellectual disability in the process. While many intellectual disabilities are caused directly by a genetic mutation in the so-called "protein coding" part of our genes, the researchers found that in their case the answer laid outside the gene and in the regulation of proteins. Protein regulation involves the switching on or off of a protein by specific genes. As a consequence ...

A joint investigation by the BMJ and Daily Telegraph has exposed the major flaws in the current EU system used for regulating medical devices, such as hip replacements and breast implants. It reveals that some "notified bodies" (the agencies charged with assessing how safe medical devices are before they are sold) are more interested in attracting business than safeguarding patients. Undercover reports created a fake large diameter metal on metal total hip—called the Changi TMH (Total Metal Hip)—that was based on a device which has been recalled globally for safety ...

Previously, there had been a lack of reliable data in Germany on the long-term psychological consequences of political imprisonment in the GDR. Professor Andreas Maercker, Head of the Department of Psychopathology and Clinical Intervention at the University of Zurich, and private lecturer Dr. Matthias Schützwohl, Group Leader at the Clinic and Polyclinic of Psychiatry and Psychotherapy at Dresden University of Technology, interviewed 146 former political prisoners in the mid-1990s. 15 years later, they studied the majority of those concerned (78 men and 15 women) again. ...

Vulnerability to major depression is linked with how satisfied we are with our lives. This association is largely due to genes. This is the main finding of a new twin study from the Norwegian Institute of Public Health in collaboration with the University of Oslo. The researchers compared longitudinal information from identical and fraternal twins to determine how vulnerability to major depression is associated with dispositional (overall) lifetime satisfaction. Previous studies have systematically shown that life satisfaction is considerably stable over time. People ...

Researchers have identified a new means to eradicate malaria infections by rapidly killing the blood-borne Plasmodium parasites that cause the disease. Malaria causes up to 3 million deaths each year, predominantly afflicting vulnerable people such as children under five and pregnant women, in tropical regions of Africa, Asia, and Latin America. Treatments are available for this disease, but the Plasmodium parasite is fast becoming resistant to the most common drugs, and health authorities say they desperately need new strategies to tackle the disease. This new potential ...