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UCLA scientists transform HIV into cancer-seeking missile

Camouflaging an impotent AIDS virus in new clothes enables it to hunt down metastasized melanoma cells in living mice, reports a UCLA AIDS Institute study in the Feb. 13 online edition of Nature Medicine. The scientists added the protein that makes fireflies glow to the virus in order to track its journey from the bloodstream to new tumors in the animals' lungs. "For the past 20 years, ge...

Scientists find fossil proof of Egypt's ancient climate

Earth and planetary scientists at Washington University in St. Louis are studying snail fossils to understand the climate of northern Africa 130,000 years ago. While that might sound a bit like relying on wooly bear caterpillars to predict the severity of winter, the snails actually reveal clues about the climate and environment of western Egypt, lo those many years ago. They also could s...

Ophthalmologists Use Artificial Silicon Retina Microchip To Treat Vision Loss

Ophthalmologists at Rush University Medical Center implanted Artificial Silicon Retina (ASR) microchips in the eyes of five patients to treat vision loss caused by retinitis pigmentosa (RP). The implant is a silicon microchip 2mm in diameter and one-thousandth of an inch thick, less than the thickness of a human hair. Four patients had surgery Tuesday, January 25. The fifth patient is sch...

Ophthalmologists implant five patients with artificial silicon retina microchip

Ophthalmologists at Rush University Medical Center implanted Artificial Silicon Retina (ASR) microchips in the eyes of five patients to treat vision loss caused by retinitis pigmentosa (RP). The implant is a silicon microchip 2mm in diameter and one-thousandth of an inch thick, less than the thickness of a human hair. Four patients had surgery Tuesday, January 25. The fifth patient is sch...

Substance protects resilient staph bacteria

Researchers have identified a promising new target in their fight against a dangerous bacterium that sickens people in hospitals, especially people who receive medical implants such as catheters, artificial joints and heart valves. A substance found on the surface of Staphylococcus epidermidis has, for the first time, been shown to protect the harmful pathogen from natural human defense m...

UCSD-Salk Team Show Protein’s Gene-Silencing Role In Development of Nervous System

The first evidence that a group of proteins called phosphatases play a key role in the development of the nervous system, has been shown in fruit flies and mice by researchers at the University of California, San Diego (UCSD) School of Medicine, in collaboration with scientists at the Salk Institute, La Jolla, California. The phosphatases are required for maintenance of neural stem cells and for...

Survey finds silver contamination in North Pacific waters

The highest levels of silver contamination ever observed in the open ocean turned up in samples collected during a survey of the North Pacific in 2002. Researchers from the University of California, Santa Cruz, measured silver concentrations 50 times greater than the natural background level. Though still well below levels that would be toxic to marine life, this contamination of what had been co...

Silence the gene, save the cell: RNA interference as promising therapy for ALS

Scientists at the Ecole Polytechnique Fédérale de Lausanne (EPFL) in Switzerland have used RNA interference in transgenic mice to silence a mutated gene that causes inherited cases of amytrophic lateral sclerosis (ALS), substantially delaying both the onset and the progression rate of the fatal motor neuron disease. Their results will be published in the April issue of Nature Medicine, and in the...

Used in a new way, RNA interference permanently silences key breast cancer gene

In laboratory mouse experiments, researchers at The University of Texas M. D. Anderson Cancer Center have developed a way to use RNA interference (RNAi) so that it permanently hampers breast cancer development. The technique permanently silences activated STAT3, a crucial gene found in some human breast tumors, thus reducing the cancer's ability to become invasive. The study, presented at...

Novel gene-silencing nanoparticles shown to inhibit Ewing's sarcoma

A novel delivery system that transports gene silencing nanoparticles into tumor cells has been shown to inhibit Ewing's sarcoma in an animal model of the disease. In this classic "Trojan horse" approach, a protein called transferrin that normally delivers iron into cells is modified to also smuggle into tumor cells siRNA (short interfering RNA) encased in nano-sized sugar polymers. The si...

Oldest fossil human protein ever sequenced

An international team led by researchers at the Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology in Liepzig, Germany and Washington University in St. Louis, has extracted and sequenced protein from a Neanderthal from Shanidar Cave, Iraq dating to approximately 75,000 years old. This is the oldest fossil human protein ever sequenced. The research will be pu...

Oldest cranial, dental and postcranial fossils of early modern European humans confirmed

The human fossil evidence from the Mladec Caves in Moravia, Czech Republic, excavated more than 100 years ago, has been proven for the first time, through modern radiocarbon dating, to be the oldest cranial, dental and postcranial assemblage of early modern humans in Europe. A team of researchers from the Natural History Museum in Vienna, from the University of Vienna in Austria and from t...

Researchers find new giant amphibian fossils in Africa

Two new 250 million year-old species of large, meat-eating amphibians have been discovered by researchers, including investigators from McGill University. Their findings published in today's issue of Nature, describe the first and oldest amphibious carnivores from the Republic of Niger in West Africa. "This the first evidence of carnivores in this area," says McGill paleontologist, and co-...

Molecular fossils uncover link between viruses and the immune system

Researchers from the Viikki Biocenter, University of Helsinki, show that atomic structures can reveal evolutionary history of viruses in a similar fashion as fossils did for the dinosaurs and reptiles. Their article is published in the April 15 issue of Molecular Cell. These "molecular fossils" also revealed that viruses and proteins of immune system share the same structure. One plausibl...

Evidence of 600-million-year old fungi-algae symbiosis discovered in marine fossils

Researchers from China and the United States have found evidence of lichen-like symbiosis in 600-million-year-old fossils from South China. The previous earliest evidence of lichen was 400 million years old, discovered in Scotland. The discovery also adds to the scarce fossil record of fungi and raises new questions about lichen evolution. Xunlai Yuan, a paleontologist with the Nanjing Ins...

Gene silencing technique offers new strategy for treating, curing disease

A new technique aimed at directly controlling the expression of genes by turning them on or off at the DNA level could lead to drugs for the treatment or cure of many diseases, say researchers at UT Southwestern Medical Center. "Virtually every disease starts at the level of malfunctioning gene expression, or viral or bacterial gene expression," said Dr. David Corey, professor of pharmacol...

Molecular steps involved in the creation of gene-silencing microRNAs identified

First discovered only a few brief years ago, microRNAs are small, remarkably powerful molecules that appear to play a pivotal role in gene silencing, one of the body's main strategies for regulating its genome. A scant 22 nucleotides in length, miRNAs appear to work by binding to and somehow interfering with messenger RNA, itself responsible for translating genes into proteins. But how do...

Spider blood found in 20 million year old fossil

A scientist from the University of Manchester has discovered the first identified droplets of spider blood in a piece of amber up to 20 million years old. The droplets are the first ident...

Space matters: Estimating species diversity in the fossil record

Estimates for the number of living species on earth range from 3.5 million to over 30 million but only 1.9 million species have been classified and described. Estimating historical biodiversity from the fossil record is an even more daunting task. One tool ecologists - but not paleontologists - have traditionally relied on to identify patterns of existing biological diversity is a long-est...

Virginia Tech, Nanjing Institute researchers discover half-billion year-old fossils

Scientists interested in ancient life have a wealth of fossils and impressions frozen in rocks that they can study from as far back as 540 million years ago ?when animals with shells and bones began to become plentiful. But evidence of complex life older than 540 million years is scant and difficult to study. Now, a research team from Virginia Tech in the United States and Nanjing Institut...

Biologists Crack Genetic Code for Specialized Spider Silk

Defects in a single gene can result in two immune system disorders that leave affected individuals vulnerable to frequent or unusually severe infections, according to new findings reported in the August issue of Nature Genetics. The discovery may lead to new diagnostic tests for these two inherited conditions ?immunoglobulin A (IgA) deficiency and common variable immunodeficiency (CVID). Currentl...

Restoring silenced suppressor gene kills lung-cancer cells

A new study suggests that restoring a gene often silenced in lung cancer causes the cells to self-destruct. The findings could lead to a new strategy for treating the disease. The research focused on a gene known as WWOX, which is lost or silenced in a large majority of lung cancers, and in cancers of the breast, ovary, prostate, bladder, esophagus and pancreas. The work was led by scient...

Missing fossil link 'Dallasaurus' found

When amateur fossil finder Van Turner discovered a small vertebra at a construction site near Dallas 17 years ago, he knew the creature was unlike anything in the fossil record. Scientists now know the significance of Turner's fossil as the origin of an extinct line of lizards with an evolutionary twist: a land-dwelling species that became fully aquatic. Turner took the remains to paleonto...

Bugs expose underground carbon traffic system 10 times more important than fossil fuel burning

The flow of carbon through soil is ten times greater than the amount of carbon moved around by the burning of fossil fuel but until now how this happens was at best poorly understood. Soil was almost literally a black box to scientists interested in carbon. Now researchers at the University of Warwick have been able to shed light in that black box by getting a particular class of insects to expos...

Fossil find: 'Godzilla' crocodile had head of a dinosaur, fins like a fish

At the southern tip of South America , they found fossils of an entirely new specie...

Twin molecular scissors link creation of microRNAs with gene-silencing

One of the body's primary strategies for regulating its genome is a kind of targeted gene silencing orchestrated by small molecules called microRNAs, or miRNAs. First observed only a few years ago, these molecules appear to inactivate messenger RNA, itself responsible for translating genes into proteins. Scientists have been eager to know more about miRNAs, clearly important players on the geneti...

'Banana-jawed' fossil mammal linked to rare sound-producing skill

Paleontologists at the Duke Lemur Center have assembled a new picture of a 35-million-year-old fossil mammal -- and they even have added a hint of sound. By painstakingly measuring hundreds of specimens of a fossil mammal called Thyrohyrax, recovered from the famous fossil beds of Egypt's Fayum Province, the researchers determined that males of this now-extinct species -- and only males --...

Researchers get neurons and silicon talking

The ultimate applications are potentially limitless. In the long term it will possibly enable the creation of very sophisticated neural prostheses to combat neurological disorders. What's more, it could allow the creation of organic computers that use living neurons as their CPU. Those applications are potentially decades away, but in the much nearer term the new technology could enable ve...

Cell barrier shows why bird flu not so easily spread among humans

Although more than 100 people have been infected with the H5N1 avian influenza virus, mostly from close contact with infected poultry, the fact that the virus does not spread easily from its pioneering human hosts to other humans has been a biomedical puzzle. Now, a study of cells in the human respiratory tract reveals a simple anatomical difference in the cells of the system that makes it...

Nano machine switches between biological and silicon worlds

"Frankly, some researchers didn't think what we were attempting was possible," says Dr Keith Firman, at Portsmouth University and Mol-Switch project coordinator, funded under the European Commission's Future and Emerging Technologies initiative. "However, we got our molecular switch to work." The upshot is that the Mol-Switch project was far more successful than expected. The team's switch...

Protein 'nanosprings' most resilient found in nature

A component of many proteins has been found to constitute one of the most powerful and resilient molecular "springs" in nature, researchers have discovered. The engineers and biologists from Duke University and the Howard Hughes Medical Institute say their discovery could lead to a new understanding of mechanical processes within the living cell. The discovery also could provide potent nanoscale...

Tool developed to silence genes in specific tissues using RNAi

Researchers at The University of Texas M. D. Anderson Cancer Center say they have jumped a significant hurdle in the use of RNA interference (RNAi), believed by many to be the ultimate tool to both decode the function of individual genes in the human genome and to treat disease. Reporting in the journal Genes and Development, investigators have developed a simple way to use the RNAi appro...

New mechanism for essential genome-wide gene silencing identified

Most of the time in most cells of the body, the great majority of genes are silenced, locked away within the compacted but orderly material that makes up chromosomes. Estimates are that only about 10 percent of the roughly 25,000 genes in the human genome are activated, or "on," at any given time in a particular cell ?the default setting for most genes is "off," or repressed. Reliable gene...

Paleontologists learn how not to become a fossil

The best way to avoid becoming a fossil is to be small and live in deep, tropical waters. So say four paleontologists who have published a detailed, global study of clam preservation. Their work is intended to enhance evolutionary studies by determining what's missing from the fossil record and why. "Everyone talks about how imperfect the fossil record is, but not many people do anything a...

'Shuttling' protein possibly key to resilience of cancer cells

Researchers at Purdue University have discovered a molecular mechanism that may play a crucial role in cancer's ability to resist chemotherapy and radiation treatment and that also may be involved in Alzheimer's and heart disease. The scientists, using an innovative imaging technique invented at Purdue, have learned that a protein previously believed to be confined to the nucleus of health...

Ancient fossil DNA found preserved in crystal

Scientists at the Weizmann Institute of Science recently discovered a new source of well-preserved ancient DNA in fossil bones. Their findings were published in the Proceedings of the National Academy of Sciences (PNAS). Fossil DNA is a potential source of information on the evolution, population dynamics, migrations, diets and diseases of animals and humans. But if it is not well preserve...

Silence of the amoebae

Freedom of expression is great, but silence is golden ?at least when it comes to amoebae, which are intestine-dwelling parasites that cause life-threatening dysentery in many parts of the world. Three years ago, scientists at the Weizmann Institute accidentally discovered a way to silence the expression of a key amoebic gene, one which codes for a toxic protein that kills human intestinal cells i...

Pathway toward gene silencing described in plants

Biologists at Washington University in St. Louis have made an important breakthrough in understanding a pathway plant cells take to silence unwanted or extra genes using short bits of RNA. Basically, they have made it possible to see where, and how, the events in the pathway unfold within the cell, and seeing is believing, as the old saying goes. Craig Pikaard, Ph.D., Washington Uni...

Non-coding RNAs help silence the mammalian transcription

Dr. Shirley Tilghman and colleagues (Princeton University) lend new insight into the mechanism of genomic imprinting, demonstrating a necessary role for a non-coding RNA transcript in the silencing of an imprinted gene cluster in mice. Imprinting, or the differential expression of a gene based upon which parent it has been inherited from, is integral to normal growth and development. Two h...

Researcher studies, treats military with 'silent disease'

For nearly four years, a researcher in Washington, D.C., has been working toward tracking how servicemembers respond to treatment for the "silent disease" hepatitis C. Dr. Maria Sjogren, a retired Army colonel and hepatologist, which is a doctor who specializes in treating liver disease, has enrolled 90 active-duty servicemembers in her study at the Walter Reed Army Medical Center. The vir...