Showing papers by "C. Shad Thaxton published in 2009"

Nanoparticle-based bio-barcode assay redefines "undetectable" PSA and biochemical recurrence after radical prostatectomy

Abstract: We report the development of a previously undescribed gold nanoparticle bio-barcode assay probe for the detection of prostate specific antigen (PSA) at 330 fg/mL, automation of the assay, and the results of a clinical pilot study designed to assess the ability of the assay to detect PSA in the serum of 18 men who have undergone radical prostatectomy for prostate cancer. Due to a lack of sensitivity, available PSA immunoassays are often not capable of detecting PSA in the serum of men after radical prostatectomy. This new bio-barcode PSA assay is ≈300 times more sensitive than commercial immunoassays. Significantly, with the barcode assay, every patient in this cohort had a measurable serum PSA level after radical prostatectomy. Patients were separated into categories based on PSA levels as a function of time. One group of patients showed low levels of PSA with no significant increase with time and did not recur. Others showed, at some point postprostatectomy, rising PSA levels. The majority recurred. Therefore, this new ultrasensitive assay points to significant possible outcomes: (i) The ability to tell patients, who have undetectable PSA levels with conventional assays, but detectable and nonrising levels with the barcode assay, that their cancer will not recur. (ii) The ability to assign recurrence earlier because of the ability to measure increasing levels of PSA before conventional tools can make such assignments. (iii) The ability to use PSA levels that are not detectable with conventional assays to follow the response of patients to adjuvant or salvage therapies.

Templated spherical high density lipoprotein nanoparticles.

Abstract: We report the synthesis of high density lipoprotein (HDL) biomimetic nanoparticles capable of binding cholesterol. These structures use a gold nanoparticle core to template the assembly of a mixed phospholipid layer and the adsorption of apolipoprotein A-I. These synthesized structures have the general size and surface composition of natural HDL and, importantly, bind free cholesterol (Kd = 4 nM). The determination of the Kd for these particles, with respect to cholesterol complexation, provides a key starting and comparison point for measuring and evaluating the properties of subsequently developed synthetic versions of HDL.

Nanostructures suitable for sequestering cholesterol and other molecules

Abstract: Articles, compositions, kits, and methods relating to nanostructures, including those that can sequester molecules such as cholesterol, are provided Certain embodiments described herein include structures having a core-shell type arrangement; for instance, a nanoparticle core may be surrounded by a shell including a material, such as a lipid bilayer, that can interact with cholesterol and/or other lipids In some embodiments, the structures, when introduced into a subject, can sequester cholesterol and/or other lipids and remove them from circulation Accordingly, the structures described herein may be used to diagnose, prevent, treat or manage certain diseases or bodily conditions, especially those associated with abnormal lipid levels

Nanostructures suitable for sequestering cholesterol

Abstract: Articles, compositions, kits, and methods relating to nanostructures, including those that can sequester molecules such as cholesterol, are provided. Certain embodiments described herein include structures having a core-shell type arrangement; for instance, a nanoparticle core may be surrounded by a shell including a material, such as a lipid bilayer, that can interact with cholesterol and/or other lipids. In some embodiments, the structures, when introduced into a subject, can sequester cholesterol and/or other lipids and remove them from circulation. Accordingly, the structures described herein may be used to diagnose, prevent, treat or manage certain diseases or bodily conditions, especially those associated with abnormal lipid levels.