Pennsylvania
Researchers report that they have created tree-like molecules that assemble themselves into precisely structured building blocks of a quarter-million atoms. Such building blocks may be precursors to designing nanostructures for molecular electronics or photonics materials, which "steer" light in the same way computer chips steer electrons.
The largest-ever study of cocaine users who suffered heart-related effects from taking the drug finds that a specially designed plan of emergency-room care for such patients can save both lives and money. Such plans have been in place for traditional chest pain patients for years, and many hospitals set aside part of their ERs to hold them for observation. But doctors have lacked criteria to help them decide how long to hold patients whose chest pain was caused by cocaine - even as millions of Americans are using the drug.
For antibiotics, the best way to beat bacterial defenses may be to avoid them altogether. Researchers at University of Pennsylvania School of Medicine have discovered that Cecropin A, a member of a family of antibiotic proteins produced by insects, may kill bacteria and avoid resistance by entering bacterial cells and taking control of their genetic machinery.
While most antibiotics kill bacteria by attacking critical enzyme systems, Cecropin A somehow slips inside the bacteria and turns specific genes on and off. The findings challenge conventional thinking on how these antibiotics function, and may aid in turning antimicrobial peptides like Cecropin A into therapeutic agents.
A Pennsylvania researcher has developed a faster method for more efficient sharing of widely distributed Internet resources such as Web services, databases and high performance computers. Jonghun Park, assistant professor in Penn State's School of Information Sciences and Technology (IST) who has proposed the protocol, says the new technology speeds up to 10 times faster the allocation of Internet resources. "In the near future, the demand for collaborative Internet applications will grow," Park says. "Better coordination will be required to meet that demand, and this protocol provides that."
Scientists have long touted carbon nanotubes as a futuristic means of delivering drugs, fortifying brittle materials and conducting current in miniaturized circuits. But attempts to introduce actual nanotubes into these roles have often been stopped in their tracks by the slender filaments' stubborn and unhelpful tendency to clump together in solution. Now scientists at the University of Pennsylvania have found that a readily available chemical, a surfactant called sodium dodecylbenzene sulfonate (NaDDBS), disperses nanotubes in water with remarkable efficiency. The discovery, described in a paper published this month in the journal Nanoletters, represents an important step towards wider applications of nanotubes.
The presence of tumor-infiltrating lymphocytes predicts the length of remission after chemotherapy and the overall survival of patients with ovarian cancer, according to researchers from the Abramson Cancer Center and the Center on Women's Health at the University of Pennsylvania School of Medicine. Their findings, which are presented in the January 16th issue of the New England Journal of Medicine, constitute the first proof that a spontaneous immune response against the tumor dramatically impacts the clinical course of ovarian cancer. These novel findings generate hope that immune therapies may significantly prolong the response to chemotherapy and improve the survival of patients with advanced ovarian carcinoma.
At some point in fetal development, cells from the newly emerged blood circulatory system start out on their own and form a separate parallel network of vessels known as the lymphatic system. In the January 10th issue of Science, researchers report the discovery of the molecular signals necessary to separate the lymph vessel network from the blood vessel network. Their findings clarify an important juncture in fetal development, shed light on the mechanisms by which molecular signals influence vascular development, pave the way for potential therapeutics, and may ultimately clear up a minor mystery among researchers that has been brewing since the mid-1990s.
Whether you fancy yourself a jet-setting sophisticate or a down-to-earth outdoorsy type, a fast-track corporate star or an all-around nice guy, new research indicates that you probably tune out information that challenges your self-image by tuning in to television. "We each have ways in which we like to perceive ourselves," said one of the lead researchers. "In many cases self-image is carefully constructed and zealously guarded, and it's difficult to experience a conflict between who we are and who we would like to be. Television appears to be an effective means of reducing awareness of how we are falling short of our own standards."
Children exposed to lead have significantly greater odds of developing delinquent behavior, according to Pittsburgh researcher. Results of the study, directed by Herbert Needleman, M.D., professor of child psychiatry and pediatrics, were published in today's issue of Neurotoxicology and Terotology. Needleman -- whose prior work was instrumental in establishing nationwide government bans on lead from paint, gasoline and food and beverage cans -- examined 194 youths convicted in the Juvenile Court of Allegheny County, Pa., and 146 non-delinquent controls from high schools in Pittsburgh. Bone lead levels, measured by K X-ray fluorescence spectroscopy of the tibia, showed that the delinquent youths had significantly higher mean concentrations of lead in their bones ? 11.0 parts per million (ppm) ? compared to 1.5 ppm in the control group.
Researchers have developed the first virtual stomach, a computer-generated model that is providing unique insights into the way medicines are released from pills and capsules. "There's no other technique to allow you to see flow patterns in a real stomach, animal or human," said lead researcher James G. Brasseur, Ph.D., a professor of mechanical engineering and bioengineering at The Pennsylvania State University. Although pills and tablets have become a ubiquitous part of our society, the detail of how the stomach breaks them down to help release their medicine remains unclear. "You can give someone a drug and measure its uptake in tissue," he said, "but the process between administering the drug and the uptake is largely guesswork."
Scientists have found a new wrinkle in the developmental biology dogma that cell differentiation occurs irreversibly as stem cells give rise to increasingly specialized types of offspring cells. The researchers have shown that certain mouse cells retain an ability to oscillate between very distinct blood cell types ? B-cells and macrophages ? long after what has been commonly regarded as the point of no return.
While type 1 Neurofibromatosis (NF1) is primarily known to cause tumors of the nervous system, scientists were puzzled as to why patients with NF1 are also prone to cardiovascular problems such as hypertension and congenital heart disease. Researchers from the University of Pennsylvania School of Medicine have solved this particular part of the puzzle by showing how the Nf1 gene - which is mutated in those suffering from Neurofibromatosis - is also essential in endothelial cells, the cells that make up blood vessels.
Rearrangements of the mixed lineage leukemia gene, MLL, are associated with aggressive leukemias in both children and adults. Researchers at the University of Pennsylvania School of Medicine have found that one portion of the MLL protein is an enzyme that "edits" the so-called histone code, a series of modifications to proteins associated with DNA that influence how and when certain genes are turned on and off. Their findings are presented in the November issue of Molecular Cell.
Scientists have successfully restored sperm production in once-infertile mice by transplanting specialized cells that are critical to sperm development. The research, reported on the Web site of the journal Biology of Reproduction, may give scientists a better understanding of how Sertoli cells ? which surround spermatogenic stem cells ? nourish sperm production and the survival of stem cells.
A new study has found that women athletes get far more pumped up before and during athletic competition than their male counterparts. Pre-event testosterone levels rise 9 percent, on avergae, in males whereas in females they increase by 24 percent. During the game itself women increase their testosterone production by 49 percent while in males, it increases on average 15 percent. The rise in testosterone that accompanies competition is thought to make the individual more willing to take risks, improves psychomotor function and coordination, and increase cognitive performance qualities that are very important in winning.
