Body

Subjective screening questions do not reliably identify teenagers who are at risk for hearing loss, according to researchers at Penn State College of Medicine. The results suggest that objective hearing tests should be refined for this age group to replace screening questions.

BOSTON - New achievements in synthetic biology announced today by researchers at the Wyss Institute for Biologically Inspired Engineering, which will allow complex cellular recognition reactions to proceed outside of living cells, will dare scientists to dream big: there could one day be inexpensive, shippable and accurate test kits that use saliva or a drop of blood to identify specific disease or infection — a feat that could be accomplished anywhere in the world, within minutes and without laboratory support, just by using a pocket–sized paper diagnostic tool.

Just like those of humans, insect guts are full of microbes, and the microbiota can influence the insect's ability to transmit diseases. A study published on October 23rd in PLOS Pathogens reports that a bacterium isolated from the gut of an Aedes mosquito can reduce infection of mosquitoes by malaria parasites and dengue virus. The bacterium can also directly inhibit these pathogens in the test tube, and shorten the life span of the mosquitoes that transmit both diseases.

Orono, Maine — In the southern Peruvian Andes, an archaeological team led by researchers at the University of Maine has documented the highest altitude ice age human occupation anywhere in the world — nearly 4,500 meters above sea level (masl).

Their discoveries date high-altitude human habitation nearly a millennium earlier than previously documented.

DURHAM, N.C. -- When pathogenic bacteria like Salmonella or Staphylococcus invade a host, the host organism should respond by going into a state of high alert, altering its metabolism to defend against the attack.

But if the host doesn't reverse course once the battle is won, its efforts will be wasted on defense rather than on repairing the damage done by bacterial invaders.

Over the last decade, powerful new microscopes have dramatically sharpened biologists' focus on the molecules that animate and propel life. Now, a new imaging platform developed by Eric Betzig and colleagues at the Howard Hughes Medical Institute's Janelia Research Campus offers another leap forward for light microscopy. The new technology collects high-resolution images rapidly and minimizes damage to cells, meaning it can image the three-dimensional activity of molecules, cells, and embryos in fine detail over longer periods than was previously possible.

To protect our oceans from irreversible harm, governments, conservationists, and researchers around the world must address the enormous threat posed by unregulated and destructive fisheries, say top marine scientists.

This news release is available in German.

A DNA mutation that can lead to horses being genetically male, but female in appearance, may explain at least two cases of controversial sexual identity, according to research led by professors from the Texas A&M College of Veterinary Medicine & Biomedical Sciences (CVM) and published in PLOS Genetics.

This type of genetic abnormality is caused by a mutation called DNA copy number variation (CNV), in which there are deletions and duplications in the genome typically larger than 50 base pairs.

Kansas City, MO. — The development of a new organism from the joining of two single cells is a carefully orchestrated endeavor. But even before sperm meets egg, an equally elaborate set of choreographed steps must occur to ensure successful sexual reproduction. Those steps, known as reproductive cell division or meiosis, split the original number of chromosomes in half so that offspring will inherit half their genetic material from one parent and half from the other.

An international team of researchers from Japan and the UK has discovered how a single protein, called PP4, oversees the processing of DNA during sperm and egg generation for successful fertilization. This protein's activity becomes even more paramount during aging. The study, published in the journal PLOS Genetics, may one day help scientists to understand the mechanisms underlying age-related fertility declines in humans.

Research conducted at the highest-altitude Pleistocene archaeological sites yet identified in the world sheds new light on the capacity of humans to survive in extreme environments.

The findings, to be published in the Oct. 24 edition of the academic journal Science – co-authored by a team of researchers including University of Calgary archaeologist Sonia Zarrillo – were taken from sites in the Pucuncho Basin, located in the Southern Peruvian Andes.

Scientists working on islands in Florida have documented the rapid evolution of a native lizard species — in as little as 15 years — as a result of pressure from an invading lizard species, introduced from Cuba.

After contact with the invasive species, the native lizards began perching higher in trees, and, generation after generation, their feet evolved to become better at gripping the thinner, smoother branches found higher up.

Ferns are believed to be 'old' plant species – some of them lived alongside the dinosaurs, over 200 million years ago. However, a group of Andean ferns evolved much more recently: their completely new form and structure (morphology) arose and diversified within the last 2 million years. This novel morphology seems to have been advantageous when colonising the extreme environment of the high Andes.

Proteins are long linear molecules that fold up to form well-defined 3D shapes. These 3D molecular architectures are essential for biological functions such as the elasticity of skin, the digestion of food, and the transport of oxygen in blood.