Dr. Cathy Shachaf's team at the Stanford University School of Medicine has developed a nanoparticle application that she expects will allow doctors to examine up to 100 distinct features in individual cancer cells — similar to how radioactive dyes are now used to highlight organs for more traditional scanning technologies. Shachaf and her term successfully integrated Raman signal emitting molecules with composite organic-inorganic nanoparticles (COINs) from Intel to boost the strength of the signals and allow the team to track changes in the functioning of certain proteins in leukemia cells that play a role in cancer development.

Two other teams are using nanoparticles to combat drug-resistant bacteria. The first team, based at the Institute of Bioengineering and Nanotechnology in Singapore, are specifically interested in using peptide nanoparticles to penetrate the blood-brain barrier in order to combat brain infections. In their studies, they've not only demonstrated that the peptide nanoparticles can — unlike most antibiotics - penetrate that barrier and successfully target bacterial, yeast or viral infections. Because of their small size, the nanoparticles enter the attacking cells, causing them to die — but without affecting normal human cells.

Brown University researchers Thomas Webster and Erik Taylor are using iron-ozide nanoparticles to kill the bacteria Staphylococcus epidermidis that has a tendency to accumulate on medical devices in therapeutic settings. The staph bacteria is particularly difficult to eliminate from medical implants — like knee and hip replacements — and often result in a full removal of the device. But Webster and Taylor found that the iron oxide nanoparticles can be forced through the bacterial cell walls with the use of magnets, virtually eliminating the staff infection from the device and — reportedly — encouraging normal bone growth around the implant.

Of course, all of this works right up until the nanoparticles give you the cancer other scientists have predicted they will.

Harnessing nanoparticles to track cancer cell changes [Nanowerk]
Singapore nanotechnology combats fatal brain infections [EurekAlert]
Implant Bacteria, Beware: Researchers Create Nano-sized Assassins [Science Daily]

[Image via the National Science Foundation]

A release from the University of Illinois explains:

Erythromycin and newer macrolide antibiotics azithromycin and clarithromycin are often used to treat respiratory tract infections, as well as outbreaks of syphilis, acne and gonorrhea. The drugs can be used by patients allergic to penicillin.

Macrolide antibiotics act upon the ribosomes, the protein-synthesizing factories of the cell. A newly-made protein exits the ribosome through a tunnel that spans the ribosome body. Antibiotics can ward off an infection by attaching to the ribosome and preventing proteins the bacterium needs from moving through the tunnel.

Some bacteria have learned how to sense the presence of the antibiotic in the ribosomal tunnel, and in response, switch on genes that make them resistant to the drug, Mankin said. The phenomenon of inducible antibiotic expression was known decades ago, but the molecular mechanism was unknown.

Mankin and his team of researchers — Nora Vazquez-Laslop, assistant professor in the Center for Pharmaceutical Biotechnology, and undergraduate student Celine Thum — used new biochemical and genetic techniques to work out the details of its operation.

"Combining biochemical data with the knowledge of the structure of the ribosome tunnel, we were able to identify some of the key molecular players involved in the induction mechanism," said Vazquez-Laslop.

"We only researched response to erythromycin-like drugs because the majority of the genetics were already known," she said. "There may be other antibiotics and resistance genes in pathogenic bacteria regulated by this same mechanism. This is just the beginning."

A report from the medical center at UC San Francisco says:

The bacteria appear to be transmitted most easily through intimate sexual contact, but can spread through casual skin-to-skin contact or contact with contaminated surfaces. The scientists are concerned that it could also soon gain ground in the general population.

The new strain of bacteria is closely related to the MRSA bacteria that have spread beyond hospital borders in recent years and caused outbreaks of severe skin and other infections. But the newly discovered microbe is resistant to many more front-line antibiotics. Both strains are technically known as MRSA USA300.

Like its less antibiotic-resistant sibling, the new multi-drug resistant microbe spreads easily through skin-to-skin contact, invading skin and tissue beneath the skin. Both strains cause abscesses and ulcerations that can progress rapidly to life-threatening infections.

Sexually-active gay men vulnerable to new bacteria [UCSF]