Biomedical Beat - A monthly digest of research news from NIGMS

July 15, 2009

Check out the Biomedical Beat Cool Image Gallery.

Got research news to share? E-mail us at

To change your subscription options or unsubscribe, visit

Biomedical Beat RSS FeedSubscribe to the RSS version of Biomedical Beat by selecting this XML link and following your news reader's instructions for adding a feed.

The National Institute of General Medical Sciences (NIGMS), one of the National Institutes of Health, supports all research featured in this digest. Although only the lead scientists are named, coworkers and other collaborators also contributed to the findings. To read additional news items, visit NIGMS News. To check out free NIGMS publications, go to the order form.

Cool Image: Organs in the Making

Copyright Stéphane Vassilopoulos and Frances Brodsky at University of California, San Francisco.
High res. image
(JPEG, 184 KB)

This eerily glowing blob isn't an alien or a creature from the deep sea—it's a mouse embryo just eight and a half days old. The green shell and core show a protein called Smad4. In the center, Smad4 is telling certain cells to begin forming the mouse's liver and pancreas. Researchers recently identified a trio of signaling pathways that help switch on Smad4-making genes, starting immature cells on the path to becoming organs. The research could help biologists learn how to grow human liver and pancreas tissue for research, drug testing and regenerative medicine. Courtesy of cell and developmental biologist Kenneth Zaret, who conducted the work at the Fox Chase Cancer Center.

NIH's National Institute of Diabetes and Digestive and Kidney Diseases also supported this work.

Full story
Zaret lab (no longer available)
Article abstract (from the June 26 issue of Science)

Fizzy Wound Healing

Zebrafish are popular animals for studying human illness. Courtesy of Monte Westerfield.
Zebrafish are popular animals for studying human illness. Courtesy of Monte Westerfield.
High res. image
(JPEG, 193 KB)

Scrape a knee or get a paper cut, and white blood cells from all over your body rush to the rescue. But how do they know about your injury? Researchers may have found the flag-raiser in a natural form of the bubbly antiseptic hydrogen peroxide. Studying zebrafish, members of Timothy Mitchison's systems biology lab at Harvard Medical School discovered that tail fin wounds release hydrogen peroxide, summoning white blood cells. When the researchers blocked hydrogen peroxide production, no white cells arrived. Now they want to see if some human immune disorders arise because lung or gut tissues make too much hydrogen peroxide.

Full story
Mitchison lab
Article abstract (from the June 18 issue of Nature)

A Twist on "Viral Media"

The H1N1 or 'swine flu' virus. Courtesy of C. S. Goldsmith and A. Balish.
The H1N1 or "swine flu" virus. Courtesy of C. S. Goldsmith and A. Balish.
High res. image
(JPEG, 1.9 MB)

The H1N1 or "swine flu" pandemic has given one group of researchers an opportunity to improve computer simulations of infectious disease spread by incorporating information about individual people during a real outbreak. Mathematical biologist Lauren Ancel Meyers at the University of Texas at Austin and collaborator Alison Galvani at Yale University posted a survey on Facebook to capture people's immediate reactions when the flu first broke out in April. Swift responses helped them fine-tune the survey and send it to a broader population. They continue to track how changes in the pandemic affect people's behavior as well as how information spreads through communities.

Full story
Meyers lab
Galvani lab

Fruit Fly Model for Charcot-Marie-Tooth Disease

Fruit flies could teach us about human nerve disease.
Fruit flies could teach us about human nerve disease.
High res. image
(JPEG, 75KB)

Some people with Charcot-Marie-Tooth disease, a nerve degeneration disorder, make a mutated form of the protein tyrosyl-tRNA synthetase, or TyrRS. Found in every animal on Earth, tRNA synthetases help our bodies make other proteins. Surprisingly, even the mutated TyrRS still does its protein-making job. To study what else might be going wrong with TyrRS to cause the human disorder, biologist Paul Schimmel at The Scripps Research Institute and his European colleagues mutated a similar protein in fruit flies. The flies experienced many symptoms of the disease, providing the first animal model for studying one form of Charcot-Marie-Tooth disease.

NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development also supported this work.

Full story
Schimmel lab
Article abstract (from the June 26 online issue of PNAS)

Tiny Tumor-Targeters

J. Manuel Perez experiments with his newly created nanoparticles. Courtesy of University of Central Florida.
J. Manuel Perez experiments with his newly created nanoparticles. Courtesy of University of Central Florida.

Many cancer drugs cause side effects by damaging healthy cells along with cancerous ones. Now, University of Central Florida biochemist J. Manuel Perez has made nanoparticles that can bring the widely used drug Taxol® only to cancer cells. In cell cultures, the tiny particles carried a vitamin-like lure that enticed voracious cancer cells to draw them in—along with the medicine. The nanoparticles can also carry fluorescent dye or magnetic iron that makes them light up in imaging machines, giving them the potential to help doctors diagnose cancer and closely monitor treatment progress.

NIH's National Cancer Institute also supported this work.

Full story
Perez lab
Article abstract (published online April 20 in Small)