It seems survival of the fittest affect every organism on Earth, even Monarch butterflies. Migratory Monarchs seem more resistant than non-migratory ones to parasite infections; scientists just uncovered why it is so. Explanation : infected monarchs quite don't make it while migrating long distances, so they can't propagate the infection once arrived at destination.

A little-studied outcome of animal migration is whether these long journeys can limit the spread of parasites by weeding out diseased animals. Monarch butterflies in eastern North America fly up to thousands of kilometers from Canada to Central Mexico – one of the longest migrations of any insect species. Emory University researchers found that monarchs infected with a protozoan parasite fly slower, tire out faster and expend more energy flying than healthy monarchs.

An international team of scientists has used gene therapy in two separate studies to renew brain cells and restore normal movements in monkeys and rats with a drug-induced form of Parkinson's disease.

The research, detailed online in the scientific publications Brain and The Journal of Neuroscience, essentially describes one strategy to halt Parkinson's disease at its onset and another strategy to treat the devastating side effects that occur when treating the disease in its later stages.

By inserting corrective genes into the brain, scientists studying small monkeys called marmosets prevented brain damage by producing therapeutic levels of a protein that helps nourish brain cells, said Ron Mandel, Ph.D., a scientist with the University of Florida's McKnight Brain Institute and Genetics Institute who was part of the research team.

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 shed light on the possible role weather and climate played in the dispersal of humans "out of Africa" and into Europe and Asia. Periods of substantially increased rainfall compared to the present are known to have occurred in the Sahara throughout the last million years, but their duration, intensity, and frequency remain somewhat unconstrained.

Affymetrix and Stratagene announced today that they have entered into a non-exclusive strategic alliance under which Stratagene will provide Affymetrix customers with new software solutions for GeneChip(R) data analysis. As part of this agreement, Stratagene will develop a new software package for Affymetrix, ArrayAssist(R) Lite, which will be offered as a standard statistical analysis solution of Affymetrix gene expression microarrays.

Individuals with moderate to severe chest pains (angina) who have not found relief from medication may benefit from a new gene therapy approach being used by cardiologists at Rush University Medical Center to grow new blood vessels in the heart.

The phase II clinical research study uses vascular endothelial growth factor-2 (VEGF-2) in the form of a solution containing a DNA plasmid that is delivered using catheterization to heart tissue that has been damaged from insufficient blood flow.

Although new HIV treatments have drastically reduced the incidence of Kaposi's sarcoma in developed countries, it remains a health threat in many developing countries. Now, researchers have discovered one way that Kaposi's sarcoma — a cancer-like viral disease traditionally associated with AIDS — triggers severe inflammation.

Don Ganem, a Howard Hughes Medical Institute (HHMI) investigator, and HHMI associate Craig McCormick, who are both at the University of California, San Francisco, published their findings in the February 4, 2005, issue of the journal Science.

If you're an organization dedicated to humane alternatives to the use of animals in research and you want to conduct research of your own that requires using animals as part of the testing, what do you do? In the case of the Physicians Committee for Responsible Medicine, you invent your own test.

PCRM president Neal Barnard, M.D., announced today that PCRM has developed the world's first cruelty-free insulin assay, a test used to measure insulin levels in individuals with diabetes. The assay, which uses no animals, was developed as part of PCRM's ongoing clinical trials to test the effects of a low-fat, vegan diet on patients with type 2 diabetes.

The opportunity to annotate the genome of the glow-in-the-dark bacterium, Vibrio fischeri, which lives in symbiotic harmony within the light organ of the bobtail squid, has helped a Virginia Tech microbiologist advance her research on quorum sensing, or how cells communicate and function as a community.

Researchers studying the newly sequenced genome of the marine bacterium V. fischeri, described this week in the Proceedings of the National Academy of Sciences (PNAS), have so far observed both differences and similarities in gene arrangement between it and pathogenic Vibrio species. V. fischeri has a lower GC content than other sequenced Vibrio species, but it is still more closely related to them than other organisms. (Among the four nucleotides that make up DNA – adenine, guanine, thymine, and cytosine (ATGC) – 'A' pairs with 'T' and 'G' pairs with 'C'. The more GC content, the more tightly DNA strands bind.)

Nano-sized particles embedded with bright, light-emitting molecules have enabled researchers to visualize a tumor more than one centimeter below the skin surface using only infrared light. A team of chemists, bioengineers and medical researchers based at the University of Pennsylvania and the University of Minnesota has lodged fluorescent materials called porphyrins within the surface of a polymersome, a cell-like vesicle, to image a tumor within a living rodent. Their findings, which represent a proof of principle for the use of emissive polymersomes to target and visualize tumors, appear in the Feb. 7 online early edition of the Proceedings of the National Academy of Science.

Regulating metabolism of fat is an important challenge for any animal, from nematodes to humans. Central players in the regulatory network are the nuclear hormone receptors (NHRs), which are transcription factors that turn on or off a set of target genes when bound by specific lipid molecules. In the premier open-access journal PLoS Biology, Keith Yamamoto and colleagues show that the nuclear hormone receptor nhr-49 controls two different aspects of fat metabolism, which interact to form a feedback system controlling the consumption and composition of fats in the nematode.

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 scheduled for a later date.