Using high-speed cinematography, scientists at Cambridge University have discovered that individual algal cells can regulate the beating of their flagella in and out of synchrony in a manner that controls their swimming trajectories. Their research was published on the 24th July in the journal Science.
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University of Utah researchers and their colleagues have identified the mutated gene in a hereditary form of a rare neuroendocrine tumor called paraganglioma (PGL). The gene, called hSDH5, is required to activate an enzyme that plays a critical role in the chemical reactions that convert biochemical energy into usable energy. This study will be published in the journal Science, to be released online in Science Express on July 23, 2009.
Human cells are able to secrete a cancer-killing protein, scientists at the University of Kentucky's Markey Cancer Center have found. Researchers led by Vivek Rangnekar, UK professor of radiation medicine, have determined that the tumor-suppressor protein Par-4, initially thought to be active only within cells expressing the Par-4 gene, is in fact secreted by most human and rodent cells and can target large numbers of cancer cells by binding to receptors on the cell surface.
It has long been thought that cells which come from the body's connective tissue are the only ones that can form the skeleton. Now, research shows that specialized bloodstream cells share a common origin with white blood cells. They too come from bone marrow and are capable of forming bone at sites distant from the original skeleton.
A new study by scientists at the University of Iowa shows why muscle membranes don't rupture when healthy people exercise.
The findings shed light on a mechanism that appears to protect cells from mechanical stress. The study, which appears online July 20-24 in Proceedings of the National Academy of Sciences (PNAS) Early Edition, also helps explain why muscle damage is so severe when this mechanism is disrupted, which occurs in certain congenital and limb-girdle muscular dystrophies.
Evolutionarily speaking, parasites make sex a worthwhile thing to do, according to a study published online on July 23rd in Current Biology, a Cell Press publication. The researchers report that freshwater snails, which can reproduce either sexually or asexually, are more likely to have sex if they live in the shallows, where the pressure from trematode parasites is more intense than it is in deeper waters.
Many birds really can't stand a racket. But when the going gets noisy, a few species of birds actually thrive, according to a new report published online on July 23rd in Current Biology, a Cell Press journal.
The findings are particularly novel in that they document the effects of noise pollution on an entire breeding bird community rather than on particular species in isolation. They also suggest that it may be possible in some cases to mitigate the loss of bird diversity through better control of noise from highways, industrial complexes, and other sources.
COLUMBUS, Ohio – A study led by researchers at the Ohio State University Comprehensive Cancer Center and Dana-Farber Cancer Institute reveals how late-stage, hormone-independent prostate tumors gain the ability to grow without need of hormones.
The onset of hormone-independent growth marks an advanced and currently incurable stage of prostate cancer.
STANFORD, Calif. — Human leukemia stem cells escape detection by co-opting a protective molecular badge used by normal blood stem cells to migrate safely within the body, according to a pair of studies by researchers at Stanford University Medical School.
"We call it the 'Don't eat me signal,'" said Ravindra Majeti, MD, PhD, assistant professor of hematology at the medical school and the co-first author of one of the studies, which focused on acute myeloid leukemia.
Researchers appear to have a new way to fix a broken heart. They have devised a method to coax heart muscle cells into reentering the cell cycle, allowing the differentiated adult cells to divide and regenerate healthy heart tissue after a heart attack, according to studies in mice and rats reported in the July 24th issue of the journal Cell, a Cell Press publication. The key ingredient is a growth factor known as neuregulin1 (NRG1 for short), and the researchers suggest that the factor might one day be used to treat failing human hearts.
Two new studies reveal a way to increase the body's appetite for gobbling up the cancer stem cells responsible for acute myeloid leukemia (AML), a form of cancer with a particularly poor survival rate. The key is targeting a protein on the surface of those cells that sends a "don't eat me" signal to the macrophage immune cells that serve as a first line of defense, according to the reports in the July 24th issue of the journal Cell, a Cell Press publication.
Injured heart tissue normally can't regrow, but researchers at Children's Hospital Boston have now laid the groundwork for regenerating heart tissue after a heart attack, in patients with heart failure, or in children with congenital heart defects. In the July 24 issue of Cell, they show that a growth factor called neuregulin1 (NRG1), which is involved in the initial development of the heart and nervous system, can spur heart-muscle growth and recovery of cardiac function when injected systemically into animals after a heart attack.
BLOOMINGTON, Ind. -- The coevolutionary struggle between a New Zealand snail and its worm parasite makes sex advantageous for the snail, whose females favor asexual reproduction in the absence of parasites, say Indiana University Bloomington and Swiss Federal Institute of Technology biologists in this week's Current Biology.
The scientists' report represents direct experimental evidence for the "Red Queen Hypothesis" of sex, which suggests sexual reproduction allows host species to avoid infection by their coevolving parasites by producing genetically variable offspring.
This release is available in http://chinese..org/zh/emb_releases/2009-07/cp-rmf072309.php">Chinese.
In a paper publishing online July 23 in Cell Stem Cell, a Cell Press journal, Dr. Shaorong Gao and colleagues from the National Institute of Biological Sciences in Beijing, China, report an important advance in the characterization of reprogrammed induced pluripotent stem cells, or iPSCs.
A new University of Colorado at Boulder study shows the strongest evidence yet that noise pollution negatively influences bird populations, findings with implications for the fate of ecological communities situated amid growing urban clamor.
The study also is the first to indicate that at least a few bird species opt for noisy areas over quiet ones, perhaps because of their vocalization pitches, a reduction in nest predators and less competition from other songbirds that prefer quiet environments.