New RNA libraries can selectively inactivate human genes
... for short hairpin RNA molecules that fold back on themselves to create a small RNA. To construct a library of mammalian genes for short hairpin RNA molecules, Hannon and his colleagues first had to settle on an optimal design for a short-hairpin-RNA molecule. "We tested a lot of different things -- for......passed on to daughter cells - that is, they are by themselves heritable. Beyond their disease manifestation, prions also occur naturally in some organisms (such as yeast) and may play important roles in their growth and development. Now, Osherovich and colleagues have identified the amino acid sequences that ...Oregon Stem Cell Center result of OHSU research strides
...ts because of their ability to generate copies of themselves and further divide into special-purpose offspring. Clonally self-renewing stem cells come in several forms, such as mesenchymal stem cells, neural stem cells and multipotent progenitor cells, and can be used to create multiple cell types, including ...Envisat fishes up facts behind Chilean giant squid invasion
... including hake, sardines and anchovies. The squid themselves are a delicacy in some parts of the world but there is no local tradition of catching or consuming them. But an explanation for the incursions was available from 800 km away in space. Envisat's Advanced Along Track Scanning Radiometer (AATSR) instr...Experiments establish 'protein-only' nature of prion infections
...ions produced at different temperatures propagated themselves as distinct strains -- providing templates for the folding of other proteins into the same shapes. Further structural analyses of two of the strains confirmed that the proteins were, indeed, folded differently. When the researchers introduced the dif...MGH study finds female mammals produce egg cells into adulthood
...be abnormal, which has been attributed to the eggs themselves being older. But the problems could instead be the result of aging of the germline stem cells that produce the oocytes. If these stem cells could be identified and isolated, a whole new set of options for treating or preventing infertility might open...Ontario researchers see increase in taste and odour-causing algae problems
...owing steadily, it is unclear whether the problems themselves are increasing or if local users are more sensitized to these issues. A study published in the current edition of the scientific journal Freshwater Biology examines sediment from 50 lake bottoms in the Muskoka-Haliburton region of Ontario. The result...UVa researchers describe method of protecting chromosomes during cell division
...Current Biology, think they know how cells protect themselves from aneuploidy when they divide in a process known as mitosis. "During mitosis, the cell divides replicated chromosomes to two daughter cells. We are studying a mitotic system that ensures that each cell receives the right number of chromosomes," sa...JCI table of contents, March 1 2004
...reening, are made up of altered cells that are not themselves cancerous but indicate an increased likelihood that a benign or cancerous tumor may subsequently form. In the March 1 issue of the Journal of Clinical Investigation, Federica Cavallo and colleagues from the University of Turin, Italy, evaluated vacci...EMBL researchers discover key molecular 'switch' in eye development of medaka fish
...wo paths: either divide to produce exact copies of themselves (called "proliferation") or to take on very specialized shapes and functions such as liver, brain or retinal cells (called "differentiation"). Building a fish or a human involves perfect timing in switching back and forth between the two processes....Key advance reported in regenerating nerve fibers
...cules alone is not enough, because the nerve cells themselves are still in a sluggish state." The researchers injured the optic nerves of rats, then used a two-pronged approach to get the axons to regenerate. To gas up the sluggish nerve cells, Dr. Dietmar Fischer, first author of the study, caused an inf...International science team tracks ocean predators around the globe
... their research collaboration was that the animals themselves could provide valuable information about their ocean habitats. Because many of the electronic tags collect oceanographic data, such as water temperature, tagged animals can act as "autonomous ocean sensors," going places and collecting data that woul...New technologies reveal mysteries of marine megafauna
...information on where these animals go the animals themselves are playing the role of oceanic probes. As they go about their lives they are collecting oceanographic information that reveals detailed, three-dimensional maps of oceanic currents and temperature changes that have been unattainable in the past. "On ...Out-of-balance ecosystems play role in demise of amphibian populations
...devour thousands of insects," he said. "The frogs themselves are also important prey for reptiles, birds and mammals." In 1999, two teams of researchers documented in Science that the larval form of Ribeiroia trematodes (parasitic flatworms) cause limb deformities in frogs. The same researchers recently impl...Comets spread Earth-life around galaxy, say scientists
...t that fertile Earth ejecta would, on impact, bury themselves in the radiation-shielded surface layers of frozen comets. A belt of such comets, the Edgeworth-Kuiper belt, lies beyond the planetary system. This belt gradually leaks comets into interstellar space, some of which will eventually reach proto-planeta...New hereditary cancer mutation found -- arrived with a German immigrant almost three centuries ago
...about HNPCC and the steps they can take to protect themselves against the cancers associated with the syndrome," says Stephanie M. Coronel, genetic research associate at Creighton Medical Center and one of the paper's co-authors. An estimated 147,500 cases of colorectal cancer occurred in the U.S.A. in 2003, ...A link between thimerosal and the brain: Can vaccines affect central nervous system function?
...ccines may lead to serious disorders that manifest themselves during childhood, including autism and ADHD. "Scientists certainly acknowledge that exposure to neurotoxins like ethanol and heavy metals can cause developmental disorders, but until now, the precise mechanisms underlying their toxicity have not been...Yeast mutations offer window into human disease
...ple, the researchers determined that genes arrange themselves in "neighbourhoods" or small networks. A gene is more likely to interact with its "neighbour," they discovered, than with more distant genes. Each yeast gene has on average about 30 of these interactions over the life of a cell, many more than had be...Avian flu: Shut down wild bird markets, experts say
...nic conditions during transport and in the markets themselves where they are forced to stand beak to beak with both wild and domestic birds, and handled by humans - all providing the ideal conditions for transmission of disease," said Dr William Karesh, Director of the WCS Field Veterinary Program. The trade i......s of people afflicted with kidney failure to treat themselves at home instead of traveling to dialysis clinics three days a week. "Current dialysis machines are based on 30-year-old technology and employ filter systems that are only about 28 percent efficient," said Michael Baker, chief executive officer of Hom...