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Mitochondrial DNA mutations play significant role in prostate cancer

Mutations in mitochondrial DNA (mtDNA) playan important role in the development of prostate cancer, according toresearch by scientists at Emory University School of Medicine and theUniversity of California, Irvine. The findings are published onlinethis week in the Proceedings of the National Academy of Sciences(PNAS). Mitochondrial DNA, which is separate from nuclear DNA, is foundin the hun...

Female sex hormones play a vital role in defense against sexually transmitted diseases

Two McMaster University studies, to be published in the Journal of Virology, show that sex hormones have a profound effect on susceptibility of female mice to the herpes simplex virus, type 2 (HSV-2 ), one of the most common sexually transmitted diseases. Charu Kaushic, assistant professor and supervisor of the studies, says the implication of this work is quite significant. "The research...

An HIV Protein Plays a Surprising Role in Gene Activation

Retroviruses are expert manipulators when it comes to co-opting their host's cellular resources. A great deal of human complexity stems from the vast repertoire of proteins and mechanisms dedicated to the business of regulating gene expression, and retroviruses like HIV have evolved myriad ways of redirecting that machinery to their own benefit. Humans and other eukaryotes have three type...

UCSD researchers maintain stem cells without contaminated animal feeder layers

The growth and maintenance of human embryonic stem cells in the absence of contaminated animal products has been demonstrated by University of California, San Diego (UCSD) School of Medicine researchers in the Whittier Institute, La Jolla, California. Published in the April 2005 issue of the journal Stem Cells, the study shows that laboratory culture media enriched by a human protein calle...

White blood cell waste disposal system plays critical regulatory role

A new research study identifies a critical inhibitory step that is a key component of the feedback circuit regulating the balance between neutrophil production and destruction. The research, published in the March issue of Immunity, suggests that the process for disposal of dying neutrophils is actively linked to neutrophil production. A clear understanding of the processes that control neutrophi...

Research Using Mouse Models Reveals A Novel Key Player In The Initiation Of Colon Cancer

Gastric and colorectal cancers account for more than 1 million deaths worldwide every year and several research groups have been working to identify the molecular events that result in the initiation and progression of these tumors. It has been established that interfering with the function of one gene, called Adenomatous Polyposis Coli (APC) has a profound effect on the cells lining the innermos...

White Blood Cell 'Waste Disposal' System Plays Critical Regulatory Role

A new research study identifies a critical inhibitory step that is a key component of the feedback circuit regulating the balance between neutrophil production and destruction. The research, published in the March issue of Immunity, suggests that the process for disposal of dying neutrophils is actively linked to neutrophil production. A clear understanding of the processes that control neutrophi...

Report that delayed motherhood decreases life expectancy of mouse offspring

The June 2005 issue of Biology of Reproduction includes a special paper by a team of Spanish scientists indicating that delayed motherhood in mice results in shorter life expectancy and reduced body weight in their offspring. Negative effects of late maternal age in women, such as abnormal numbers of chromosomes in their children, are well known. However, other potential negative effects o...

Conserved amino acids play both structural and mechanistic roles in sandwich-like protein

The question of whether amino acids in sandwich-like proteins are there to stabilize the structure or to speed up the protein-folding process is best answered by "all of the above," according to researchers at Rice University in Houston. This discovery, reported in today's issue of the Proceedings of the National Academy of Sciences, could benefit future research on treatments for disease...

Low oxygen likely made Great Dying worse, greatly delayed recovery

The biggest mass extinction in Earth history some 251 million years ago was preceded by elevated extinction rates before the main event and was followed by a delayed recovery that lasted for millions of years. New research by two University of Washington scientists suggests that a sharp decline in atmospheric oxygen levels was likely a major reason for both the elevated extinction rates and the v...

Circulating stem cells play small role in lung repair

Circulating stem cells play a minor role in repairing lung damage, according to a team of scientists who used male and female chromosomal differences to analyze the repair process in lung transplant patients. Reporting in today's edition of the journal Transplantation, lead author Dani Zander, M.D., of The University of Texas Medical School at Houston, and colleagues at the University of F...

MicroRNAs play a big part in gene regulation - and evolution

Regulating when and where certain proteins are made is crucial to the normal functioning of living things. To make proteins, information from DNA is transcribed into RNA molecules and then translated into the amino acids building blocks of proteins. But not all genes code for proteins--some make RNA molecules called microRNAs. These small RNA molecules interfere with--and therefore control--the p...

Specialized immune-system B cells play double-barreled role

A specialized subpopulation of the antibody-producing B cells of the immune system plays a "double-barreled" role in triggering both kinds of immunity -- innate and acquired, Duke University Medical Center immunologists have discovered. The division of labor between B-1a and B-1b cells they have uncovered offers basic insights that could contribute to more rational development of vaccines, they s...

Micro-molecule plays big role in birth defects

University of Florida researchers have learned how to selectively shut down a flyweight-sized genetic molecule that packs a heavyweight punch, a discovery that may help doctors better understand cancer, birth defects and other health problems. The finding, which will be reported this week in the online Proceedings of the National Academy of Sciences, deals with tiny strands of genetic mate...

Team of international scientists departs today to discover the unknown in China's Himalayan region

In the quest to discover new species, a team of international scientists leaves today on a month-long expedition to explore the undiscovered treasures in the Mountains of Southwest China, an extension of the great Himalayan mountain range. "Expedition Everest: Mission Himalayas" is a scientific and cultural journey to explore one of the planet's richest and most biologically diverse regio...

Marine bacterium suspected to play role in global carbon and nitrogen cycles

Scientists successfully grow 'dwarf belonging to the sea' in laboratoryScientists are now revisiting, and perhaps revising, their thinking about how Archaea, an ancient kingdom of single-celled microorganisms, are involved in maintaining the global balance of nitrogen and carbon. Researchers have discovered the first Archaea known to oxidize ammonia for energy and metabolize carbon dioxide by su...

Sleeping beauty plays a significant role in identifying cancer genes

Researchers at the University of Minnesota Cancer Center and the National Cancer Institute (NCI), part of the National Institutes of Health, have discovered a new method that could accelerate the way cancer-causing genes are found and could lead to a more accurate identification of the genes, according to two studies in the July 14, 2005, issue of Nature. The gene identification method was...

Huntington's cure in flies lays groundwork for broader treatment approaches

Boosting levels of two critical proteins that normally shut down during Huntington's disease, researchers at the University of Wisconsin-Madison and the Cold Spring Harbor Laboratory have cured fruit flies of the genetic, neurodegenerative condition. The study results,...

Fluoride poisoning in China due to clay, not coal

Millions of people in southwest China suffer from potentially-crippling fluoride poisoning because they burn a mixture of clay and coal, say researchers. Because of this belief, last year, the...

Micro RNAs play role in egg making

Researchers at Northwestern University and Carnegie Mellon University have found that a recently described class of molecules called microRNAs (miRNAs) play an important role in regulating oogenesis, the process by which females make eggs. MiRNAs silence genes by binding to genetic elements called messenger RNA and preventing them from making new proteins -- the molecules primarily responsible fo...

Virginia Tech football player uses prototype cast

Virginia Tech's starting running back Cedric Humes was able to play against Boston College despite a broken arm (the ulna bone) thanks, in part, to a prototype composite brace designed for him by Virginia Tech engineers. Brian Love, a professor of materials science and engineering in the College of Engineering, and his biomaterials class met with Mike Goforth, Virginia Tech's director of a...

Noise And Delays Explain Why Some Genes Oscillate In Activity

If you snooze, you lose those uncomely grayish-brown crescents below your eyes. If you don't snooze, you lose a lot more. The body can't fight off infection, the muscles can't regenerate as quickly, the mind can't learn new words, and the eyes can't focus on the road. You also gain things: a bad mood and increased risk for diabetes, high blood pressure, and heart problems. Indeed, the effects of...

Scientist measures role of science's coolest player: The snow

What would the Earth be like if one fine day all the snow melted away? Obviously, it would be a much warmer place. But what's interesting is how much warmer, says Stephen Vavrus, an associate scientist at the Center for Climatic Research at the University of Wisconsin-Madison. Working with computer-generated simulations, Vavrus found that in the absence of snow cover, global temperatures w...

A biosensor layered like lasagna

In a mixing of pasta metaphors, Pacific Northwest National Laboratory scientists have used electrostatic attraction to layer reactive biological molecules lasagna-like around spaghetti-like carbon nanotubes. This configuration can accommodate a wide range of applications, from ultra-precise blood-sugar monitoring to infectious-agent detection, said Yuehe Lin, who led the research at the D...

Sexual reproduction delays aging in a mammalian species

Past research on aging and the life histories of diverse species has shown that sexual reproduction is biologically costly for individuals and tends to decrease lifespan rather than increase it. But a new study by Philip Dammann and Hynek Burda from the University of Duisburg-Essen shows that, in a vertebrate species, the opposite can be true as well. The authors, studying captive Zambian...

Scientists discover interplay between genes and viruses in tiny ocean plankton

New evidence from open-sea experiments shows there's a constant shuffling of genetic material going on among the ocean's tiny plankton. It happens via ocean-dwelling viruses, scientists report this week in the journal Science. Conducted by biological oceanographers Sallie Chisholm and her colleagues at the Massachusetts Institute of Technology, the research is uncovering a new facet of evo...

Common enzyme is a key player in DNA repair

A quarter century after they discovered it, researchers have identified the job of one of the most common DNA-damage response proteins. The enzyme has puzzled scientists because it is present in nearly every organism, which suggests that it is crucial to life, and yet, in laboratory experiments, its function has remained a mystery. The discovery suggests that the enigmatic enzyme known a...

Berkeley researchers lay groundwork for cell version of DNA chip

A new technique in which single strands of synthetic DNA are used to firmly fasten biological cells to non-biological surfaces has been developed by researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley. This technique holds promise for a wide variety of applications, including biosensors, drug-screening technologies, the growing o...

Resveratrol prolongs lifespan and delays onset of aging-related traits in a short-lived vertebrate

By studying a particularly short-lived fish species, researchers have been able to show that a natural compound previously shown to extend lifespan in non-vertebrate organisms can also do so in at least one vertebrate species. The findings, reported by Alessandro Cellerino of the Scuola Normale Superiore, Pisa, and colleagues, support the potential utility of the compound in human aging research....

Vital ocean prey play active role in environment

Although Antarctic krill (Euphausia superba) are one of the best-studied organisms of the open sea, key aspects of their life cycle have remained murky. Understanding krill is important because they are vital prey for fish, birds, and marine mammals, yet they are vulnerable to fishing pressure and environmental change. In the February 2006 issue of BioScience, the monthly journal of the Am...

Man's best friend: Study shows lonely seniors prefer playtime with pooch over human interaction

A new Saint Louis University study shows there is some truth in the old cliché that describes a dog as "man's best friend." Nursing...

Study may help slay 'Yellow Monster'

Low-grade uranium ore is nicknamed "yellowcake" for its color and powdered consistency. The Navajo have another name: Leetso, or "yellow monster." The yellow monster surfaced on the Navajo Nation with uranium mining that started in the 1940s and continued for the next several decades. In its aftermath came illnesses such as lung cancer among mine workers and worries about environmental con...

Himalayan forests disappearing

Studies in which monkeys were asked to manipulate computer cursors for fruit juice rewards have revealed that the brain's "executive" center plans behaviors not by specifying movements required for given actions, but rather the events that will result from those actions. The distinction is significant, said the researchers, because it yields new basic insight into a central function of beh...

Promising cell protein may play role in infection and dry eye

Plasminogen Activator Inhibitor Type 2 (PAI-2), a protein found in various cell types including the skin, has been discovered in the tissue covering the eye and may have future clinical implications in various pathologies of the ocular surface such as eye infection or dry eye, according to researchers at the University of Pennsylvania and Temple University. The researchers, led by Mina Mas...

Neural stem cell gene plays crucial role in eye development

Scientists at the University of North Carolina at Chapel Hill have demonstrated that normal development of the eye requires the right amount of a neural stem cell gene be expressed at the right time and place. Neural stem cells are cells that can differentiate into different cell types in the nervous system. In the developing eye, retinal neural stem cells differentiate to form the neuron...

Study shows frogs can play key role in stem cell research

It sounds like one of those curiosities which pops up in wildlife documentaries, but the African clawed frog could prove a powerful ally for scientists working in the key area of stem cell research. Researchers at the University of Edinburgh have discovered that the distinctive species ?which has become popular in recent years as a domestic pet ?shares with humans the same genetic mechanism that...

Report focuses on the role good microbes play in future medicine

Not all bacteria are bad. In fact, beneficial microbes could represent the future of medicine, with the potential to treat a variety of diseases in humans and animals from diarrhea and eczema to gum disease and autoimmune disorders, according to a report released by the American Academy of Microbiology, Probiotic Microbes: The Scientific Basis. "Theoretically, beneficial microorganisms c...

Got inexpensive contrast agent? Milk plays new role in imaging

In a new twist on the slogan “milk does a body good,?radiologists are testing use of the dairy staple as a contrast agent in gastrointestinal imaging exams—with excellent results. The researchers reported their findings today at the annual meeting of the Radiological Society of North America (RSNA). “We are able to achieve similar bowel distension and enhancement as we see with the commonl...

Zinc plays important role in brain circuitry

To the multitude of substances that regulate neuronal signaling in the brain and spinal cord add a new key player: zinc. By engineering a mouse with a mutation affecting a neuronal zinc target, researchers have demonstrated a central role for zinc in modulating signaling among the neurons. Significantly, they found the mutant mouse shows the same exaggerated response to noise as children with the...

Fish species plays surprise role in aiding coral reef recovery

In a study that marks progress in understanding the basis of coral reef recovery, researchers have revealed the critical importance of a rare batfish, Platax pinnatus, in promoting the return to health of a disturbed coral reef overgrown with algae. The findings bring to light a previously unrecognized role for the batfish species, which had not been considered a significant player in reef recove...