Researchers at Johns Hopkins have discovered how cells fine-tune their oxygen use to make do with whatever amount is available at the moment.

Too little oxygen threatens life by compromising mitochondria that power it, so when oxygen is scarce, cells appear to adjust by replacing one protein with an energy-efficient substitute that "is specialized to keep the motor running smoothly even as it begins to run out of gas," says Gregg Semenza, M.D., Ph.D., a professor of pediatrics and director of the vascular biology program in the Institute for Cell Engineering at Hopkins. "This is one way that cells maintain energy production under less than ideal conditions." A report on the work is in the April 6 issue of Cell.

In advanced cancer, anti-tumor therapies often work only partially or not at all, and tumors progress following treatment.

Vanderbilt-Ingram Cancer Center scientists have now linked a treatment-induced growth factor to the cancer’s future spread.

For several types of cancer, persistently high levels of the soluble factor TGF-beta in the blood after surgery, chemotherapy, or radiation therapy correlate with increased risk of early metastasis and a poor prognosis.

Researchers at the University of Pennsylvania School of Medicine & School of Engineering and Applied Science have discovered a better way to deliver drugs to tumors. By using a cylindrical-shaped carrier they were able sustain delivery of the anticancer drug paclitaxel to an animal model of lung cancer ten times longer than that delivered on spherical-shaped carriers. These findings have implications for drug delivery as well as for better understanding cylinder-shaped viruses like Ebola and H5N1 influenza.

In findings the authors called "unexpected and striking," researchers found that a new regulating messenger IP4, a small soluble molecule, augments the binding of three different PH domain proteins to one of the most commonly recognized membrane lipids, PIP3. The study also showed that inhibiting production of IP4 can result in reduced protein binding to membranes and reduced activation of key signaling molecules in developing T cells, leading to a block of T cell maturation and to severe immunodeficiency in animal models.

Researchers have demonstrated a prototype nanometer-scale generator that produces continuous direct-current electricity by harvesting mechanical energy from such environmental sources as ultrasonic waves, mechanical vibration or blood flow.

Based on arrays of vertically-aligned zinc oxide nanowires that move inside a novel “zig-zag” plate electrode, the nanogenerators could provide a new way to power nanoscale devices without batteries or other external power sources.