Introduction: The CYP2D6 enzyme metabolizes opioids commonly prescribed for cancer-related pain, and CYP2D6 polymorphisms may contribute to variability in opioid response. We evaluated the feasibility of implementing CYP2D6-guided opioid prescribing for patients with cancer and reported pilot outcome data.
Methods: Adult patients from two cancer centers were prospectively enrolled into a hybrid implementation-effectiveness clinical trial and randomized to CYP2D6-genotype-guided opioid selection, with clinical recommendations, or usual care.
Environmental hazards typically are encountered in the gaseous phase; however, selective sensing modalities for identifying and quantitating compounds of interest in an inexpensive, pseudo-real-time format are severely lacking. Here, we present a novel proof-of-concept that combines an Air2Liquid sampler in conjunction with an oil-in-water microfluidic assay for detection of organophosphates. We believe this proof-of-concept will enable development of a new platform technology for semivolatile detection that we have demonstrated to detect 50 pmoles (2 ppb) of neurotoxic organophosphates.
View Article and Find Full Text PDFIntroduction: Pain is one of the most burdensome symptoms associated with cancer and its treatment, and opioids are the cornerstone of pain management. Opioid therapy is empirically selected, and patients often require adjustments in therapy to effectively alleviate pain or ameliorate adverse drug effects that interfere with quality of life. There are data suggesting CYP2D6 genotype may contribute to inter-patient variability in response to opioids through its effects on opioid metabolism.
View Article and Find Full Text PDFDNA aptamers that bind biomolecular targets are of interest as the recognition element in colorimetric sensors based on gold nanoparticles (AuNP), where sensor functionality is related to changes in AuNP colloidal stability upon target binding. In order to understand the role of target binding on DNA-AuNP colloidal stability, we have used high-resolution NMR to characterize the interactions of the 36 nucleotide cocaine-binding aptamer (MN4) and related aptamers with AuNPs, cocaine, and cocaine metabolites. Changes in the aptamer imino proton NMR spectra with low (20 nM) concentrations of AuNP show that the aptamers undergo fast-exchange adsorption on the nanoparticle surface.
View Article and Find Full Text PDFSmall molecules provide rich targets for biosensing applications due to their physiological implications as biomarkers of various aspects of human health and performance. Nucleic acid aptamers have been increasingly applied as recognition elements on biosensor platforms, but selecting aptamers toward small molecule targets requires special design considerations. This work describes modification and critical steps of a method designed to select structure-switching aptamers to small molecule targets.
View Article and Find Full Text PDFThe feasibility of using aptamer-gold nanoparticle conjugates (Apt-AuNPs) to design colorimetric assays for in the field detection of small molecules was investigated. An assay to detect cocaine was designed using two clones of a known cocaine-binding aptamer. The assay was based on the AuNPs difference in affinity for single-stranded DNA (non-binding) and double stranded DNA (target bound).
View Article and Find Full Text PDFFive anthranilic acid derivatives, a mixture I of three new compounds 11'-hexadecenoylanthranilic acid (1), 9'-hexadecenoylanthranilic acid (2), and 7'-hexadecenoylanthranilic acid (3), as well as a new compound 9,12,15-octadecatrienoylanthranilic acid (4) together with a new natural product, hexadecanoylanthranilic acid (5), were isolated from Geijera parviflora Lindl. (Rutaceae). Their structures were elucidated by extensive spectroscopic measurements, and the positions of the double bonds in compounds 1-3 of the mixture I were determined by tandem mass spectrometry employing ozone-induced dissociation.
View Article and Find Full Text PDFTwo novel alkaloids (parvifloranines A and B), possessing an unusual 11-carbon skeleton linked with amino acids, were isolated from Geijera parviflora, an endemic Australian Rutaceae. Their structures were elucidated by extensive spectroscopic measurements including 2D NMR analyses. Parvifloranine A was found to be a mixture of two enantiomers, (S)-1 and (R)-1, in a ratio of 1:4, based on their separation using a chiral column.
View Article and Find Full Text PDFEncapsulation of macrocyclic europium(III) chelates by discrete, monodisperse SiO2 nanoparticles (NPs) has been carried out, and the resulting significant enhancement of metal-derived luminescence has been studied to rationalize this dramatic effect. The tetraiminodiphenolate motif chosen for this study is easily synthesized and incorporated into the NP matrix under ambient conditions. The free complex exhibits primarily weak ligand-derived emission at room temperature, typical for these compounds, and displays intense metal-centered luminescence from the europium only when cooled to 77 K.
View Article and Find Full Text PDFAnal Bioanal Chem
November 2012
The genotoxicity of a molecule refers to its ability to interact with DNA in a way that inhibits normal DNA replication and transcription possibly leading to mutagenesis or carcinogenesis. Assessing the genotoxicity of a compound is critical in the development of pharmaceuticals and other products designed for human consumption or use. Typically genotoxicity is established using expensive and time consuming methods using animals or bacteria like the Ames test, mouse lymphoma assay, or mouse and rat carcinogenicity tests.
View Article and Find Full Text PDFAptamer-conjugated nanoparticles (ACNPs) have been used for a variety of applications, particularly dual nanoparticles for magnetic extraction and fluorescent labeling. In this type of assay, silica-coated magnetic and fluorophore-doped silica nanoparticles are conjugated to highly selective aptamers to detect and extract targeted cells in a variety of matrixes. However, considerable improvements are required in order to increase the selectivity and sensitivity of this two-particle assay to be useful in a clinical setting.
View Article and Find Full Text PDFBiosensors based on antibody recognition have a wide range of monitoring applications that apply to clinical, environmental, homeland security, and food problems. In an effort to improve the limit of detection of the Naval Research Laboratory (NRL) Array Biosensor, magnetic nanoparticles (MNPs) were designed and tested using a fluorescence-based array biosensor. The MNPs were coated with the fluorescently labeled protein, AlexaFluor647-chicken IgG (Alexa647-chick IgG).
View Article and Find Full Text PDFEarly and accurate detection of cancer often requires time-consuming techniques and expensive instrumentation. To address these limitations, we developed a colorimetric assay for the direct detection of diseased cells. The assay uses aptamer-conjugated gold nanoparticles to combine the selectivity and affinity of aptamers and the spectroscopic advantages of gold nanoparticles to allow for the sensitive detection of cancer cells.
View Article and Find Full Text PDFThis paper reports on the isolation and identification of antibacterial constituents from the indigenous Australian medicinal plant Eremophila duttonii F. Muell. (Myoporaceae).
View Article and Find Full Text PDFWe have extended the use the aptamer-conjugated nanoparticles for the collection and detection of multiple cancer cells. The aptamers were selected using a cell-based SELEX strategy in our laboratory for cancer cells that, when utilized in this method, allow for the selective recognition of the cells from complex mixtures including fetal bovine serum samples. Aptamer-conjugated magnetic nanoparticles were used for the selective targeting cell extraction, and aptamer-conjugated fluorescent nanoparticles were employed for sensitive cellular detection.
View Article and Find Full Text PDFWe have developed a method for the rapid collection and detection of leukemia cells using a novel two-nanoparticle assay with aptamers as the molecular recognition element. An aptamer sequence was selected using a cell-based SELEX strategy in our laboratory for CCRF-CEM acute leukemia cells that, when applied in this method, allows for specific recognition of the cells from complex mixtures including whole blood samples. Aptamer-modified magnetic nanoparticles were used for target cell extraction, while aptamer-modified fluorescent nanoparticles were simultaneously added for sensitive cell detection.
View Article and Find Full Text PDFNanoparticles for the extraction of peptides and subsequent analysis using atmospheric pressure matrix-assisted laser desorption/ionization (APMALDI) have been evaluated. The atmospheric pressure source allows for particles to be directly introduced in the liquid matrix, minimizing sample loss and analysis time. Described in this work are two sample preparation procedures for liquid APMALDI analysis: a C18 functionalized silica nanoparticle for hydrophobic extractions, and an aptamer functionalized magnetite core nanoparticle for rapid, affinity extractions.
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