The delicate interplay of two chemical signals coaxes stem cells into becoming hair follicles, according to new research by scientists at the Howard Hughes Medical Institute at The Rockefeller University.
The research has implications for understanding hair growth and hair-follicle development, and it may also help explain how diverse structures, such as teeth and lungs, are formed or how some forms of skin cancer develop.
In an article published in the March 20, 2003, issue of the
The human body has barriers such as skin and the lining of airways and gut that protect and separate us from the outside world. If these barriers are breached, our survival is threatened. Therefore it is critical that the cells that form these barriers have mechanisms that can instantly repair any injury.
University of Iowa researchers have discovered a surprisingly simple but effective repair system in airway barrier cells. The UI study shows that by placing a messenger molecule on one side
New research shows that a more effective method of genetic engineering could be used to eradicate or manipulate entire, wild populations of harmful species rather than simply small, managed populations, as is currently the case. The research,* to be published in Proceedings B, a learned journal produced by the Royal Society, shows in computer simulations how a single, selfish gene could be used to infect the host and eliminate problem genes, for example a gene allowing mosquit
Discovery points to one possible path to novel drug development for cancer, AIDS, some inflammation
Using a new approach, Mayo Clinic researchers have successfully “taught” an RNA molecule inside a living cell to work as a decoy to divert the actions of the protein NF-kappaB, which scientists believe promotes disease development. The findings are published in the current issue of Proceedings of the National Academy of Sciences.
Although it also plays helpful roles in the bod
Johns Hopkins scientists have discovered that primitive human embryonic stem (ES) cells, temperamental in the lab, can be grown with the help of special cells from bone marrow, offering an easily obtained and well-studied source of human cells to nurture the human ES cells as they divide.
First announced in 1998, human embryonic stem cells are usually grown in the lab on a “feeder layer” of mouse cells. Feeder cells send as yet unknown signals to the primitive human ES cells, preventing the
The popular stimulant blocks adenosine receptors, and is the most likely mechanism of central nervous actions that delay exercise-related fatigue, a new study finds
Consuming caffeine, whether in coffee of soft drinks, has been shown to delay fatigue during prolonged exercise. Studies have shown, for example, that ingesting three to nine mg/kg of caffeine can increase the amount of exercise time to achieve by as much as 50 percent. How caffeine achieves this effect has not been ful
Proteins, it appears, have taken Frank Sinatras “I Did It My Way” close to heart. A new study published in the current issue of Proceedings of the National Academy of Sciences (PNAS) reveals how single proteins, each a few nanometers (billionths of a meter) long, fold to assume their final shape. It shows that even proteins having the same final shape achieve it by taking different routes.
Proteins are the fundamental components of all living cells. They start out as randomly shaped c
In at least one type of endeavor, humans cant even begin to compete with their best friends. Dogs can be trained to sniff out drugs and explosives or to track down a crime suspect by smell. Why cant we do the same? Scientists from the Weizmann Institute of Science and the Max Planck Institute for Evolutionary Anthropology propose an explanation for this ancient quandary.
All mammals, including humans, have about 1,000 genes encoding smell-detecting proteins, or olfactory recepto
A team of scientists from Cambridge University and Bristol University, led by Dr Naomi Langmore of the Australian National University, has found that some Australian birds are one step ahead of their British counterparts in their ability to avoid being victimized by cuckoos.
Cuckoos exploit other bird species by laying their eggs in the nests of other birds. Soon after hatching, the cuckoo chick kills host young by tipping them out of the nest. The foster parents then work hard to rear the i
Scientists at Rockefeller University and Weill Medical College of Cornell University have discovered how estrogen initiates physical changes in rodent brain cells that lead to increased learning and memory — a finding, the researchers contend, that illustrates the likely value of the hormone to enhance brain functioning in women.
Their study, published in the March 15 issue of The Journal of Neuroscience, describes for the first time a chain of molecular events that is activated in the brain
Imagine a mask that could allow a person to breathe the oxygen in the air without the risk of inhaling a toxic gas, bacterium or even a virus. Effectively filtering different kinds of molecules has always been difficult, but a new process by researchers at the University of Rochester may have paved the way to creating a new kind of membrane with pores so fine they can separate a mixture of gases. Industries could use these types of membranes for extracting hydrogen from other gases for fuel cells tha
Scientists at the University of Pennsylvania and the Monell Chemical Senses Center in Philadelphia have found that exposure to male perspiration has marked psychological and physiological effects on women: It can brighten womens moods, reducing tension and increasing relaxation, and also has a direct effect on the release of luteinizing hormone, which affects the length and timing of the menstrual cycle.
The results will be published in June in the journal Biology of Reproduction and
New data suggests that a novel molecule appears to be involved in the intestine’s response to infection. The study was a collaboration between researchers at Washington University School of Medicine in St. Louis and the Institut Curie in Paris. It appears in the March 13 issue of the journal Nature.
“This is the first identified function for this molecule,” says co-senior author Susan Gilfillan, Ph.D., research instructor in pathology and immunology at the School of Medicine. “Our findings s
The Goualougo Triangle, nestled between two rivers in a Central African rain forest, is so remote that primate researchers who traveled 34 miles, mostly by foot, from the nearest village through dense forests and swampland to get there, have discovered a rare find: chimpanzees that have had very little or no contact at all with humans.
The chimpanzees’ behavior when first coming in contact with the researchers was a telltale sign of lack of human exposure — the chimpanzees didn’t run and
Discovery highlights molecular screening work at Institute of Chemistry and Cell Biology
Boston, Mass. — Scientists studying how cells know when and where to divide now have a new tool to study the final fast stage of cell division. The first experiments using this new tool reveal some of the molecular conversation that helps a cell tightly choreograph the time and place of pinching into two cells. In the March 14 Science, researchers from Harvard Medical School (HMS) and colleagues report
Study featured on cover of the journal Nature
Hormones and neurotransmitters secreted from cells via bubble-like vesicles are released using age-related criteria, with the youngest vesicles getting first shot at releasing their contents, according to research led by a University of Southern California (USC) physiologist. This is a “complete reverse” from what had previously been presumed to be the process behind hormone secretion, notes Robert Chow, M.D., Ph.D., associate professor of