July 22nd, 2011 by Medgadget in Research
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A new contrast agent based on maltodextrin has been developed at Georgia Tech that can provide in vivo imaging of bacteria with a sensitivity two orders of magnitude greater than previously achieved.
Unlike most previous methods, the new probes are able to enter bacterial cells by pretending to be food, while avoiding being ingested by the mammalian cells.
From Georgia Tech:
Maltodextrin-based imaging probes consist of a fluorescent dye linked to maltohexaose, which is a major source of glucose for bacteria. The probes deliver the contrast agent into bacteria through the organism’s maltodextrin transporter, which only exists in bacterial cells and not mammalian cells.
In experiments using a rat model, the researchers found that Read more »
*This blog post was originally published at Medgadget*
March 2nd, 2011 by Medgadget in Better Health Network, Research
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Our modern armamentarium for treating cancer is impressive, but sometimes despite our best treatments, tumor cells continue to lurk in the bloodstream, seeding metastases throughout the body. Researchers at Emory have developed a way to monitor for these circulating tumor cells using gold nanoparticles.
This technique has been used before, but difficulty was encountered because white blood cells are close to the same size as some tumor cells, so they would both be tagged, necessitating a laborious multi-antibody staining process.
“The key technological advance here is our finding that polymer-coated gold nanoparticles that are conjugated with low molecular weight peptides such as EGF are much less sticky than particles conjugated to whole antibodies,” says Shuming Nie, Ph.D., a professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. “This effect has led to a major improvement in discriminating tumor cells from non-tumor cells in the blood.”
Once these tumor cells are tagged with the gold nanoparticles, laser illumination reveals which cells are tumors in the bloodstream. This technique was tested on 19 patients with head and neck cancer, and showed excellent correlation with previous techniques. If this method can be validated in larger studies, it shows promise as a faster, more economical method to detect circulating tumor cells.
Full story: Nanoparticles May Enhance Circulating Tumor Cell Detection …
Abstract in Cancer Research : Quantification of circulating tumor cells in peripheral blood using EGFR-targeting gold nanoparticles
*This blog post was originally published at Medgadget*
