Browsing by Author "Talavera, Humberto"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Application of programmable bio-nano-chip system for the quantitative detection of drugs of abuse in oral fluids
    (Elsevier, 2015) Christodoulides, Nicolaos; De La Garza, Richard II; Simmons, Glennon W.; McRae, Michael P.; Wong, Jorge; Newton, Thomas F.; Smith, Regina; Mahoney, James J. III; Hohenstein, Justin; Gomez, Sobeyda; Floriano, Pierre N.; Talavera, Humberto; Sloan, Daniel J.; Moody, David E.; Andrenyak, David M.; Kosten, Thomas R.; Haque, Ahmed; McDevitt, John T.
    Objective: There is currently a gap in on-site drug of abuse monitoring. Current detection methods involve invasive sampling of blood and urine specimens, or collection of oral fluid, followed by qualitative screening tests using immunochromatographic cartridges. While remote laboratories then may provide confirmation and quantitative assessment of a presumptive positive, this instrumentation is expensive and decoupled from the initial sampling making the current drug-screening program inefficient and costly. The authors applied a noninvasive oral fluid sampling approach integrated with the in-development chip-based Programmable bio-nano-chip (p-BNC) platform for the detection of drugs of abuse. Method: The p-BNC assay methodology was applied for the detection of tetrahydrocannabinol, morphine, amphetamine, methamphetamine, cocaine, methadone and benzodiazepines, initially using spiked buffered samples and, ultimately, using oral fluid specimen collected from consented volunteers. Results: Rapid (∼10 min), sensitive detection (∼ng/mL) and quantitation of 12 drugs of abuse was demonstrated on the p-BNC platform. Furthermore, the system provided visibility to time-course of select drug and metabolite profiles in oral fluids; for the drug cocaine, three regions of slope were observed that, when combined with concentration measurements from this and prior impairment studies, information about cocaine-induced impairment may be revealed. Conclusions: This chip-based p-BNC detection modality has significant potential to be used in the future by law enforcement officers for roadside drug testing and to serve a variety of other settings, including outpatient and inpatient drug rehabilitation centers, emergency rooms, prisons, schools, and in the workplace.
  • Thumbnail Image
    Item
    Programmable bio-nanochip-based cytologic testing of oral potentially malignant disorders in Fanconi anemia
    (Wiley, 2015) Floriano, Pierre; Abram, Tim; Taylor, Leander; Le, Cathy; Talavera, Humberto; Nguyen, Michael; Raja, Rameez; Gillenwater, Ann; McDevitt, John; Vigneswaran, Nadarajah
    Fanconi anemia (FA) is caused by mutations of DNA repair genes. The risk of oral squamous cell carcinoma (OSCC) among FA patients is 800-folds higher than in the general population. Early detection of OSCC, preferably at it precursor stage, is critical in FA patients to improve their survival. In an ongoing clinical trial, we are evaluating the effectiveness of the programmable bio-nanochip (p-BNC)-based oral cytology test in diagnosing oral potentially malignant disorders (OPMD) in non-FA patients. We used this test to compare cytomorphometric and molecular biomarkers in OSCC cell lines derived from FA and non-FA patients to brush biopsy samples of a FA patient with OPMD and normal mucosa of healthy volunteers. Our data showed that expression patterns of molecular biomarkers were not notably different between sporadic and FA-OSCC cell lines. The p-BNC assay revealed significant differences in cytometric parameters and biomarker MCM2 expression between cytobrush samples of the FA patient and cytobrush samples of normal oral mucosa obtained from healthy volunteers. Microscopic examination of the FA patient's OPMD confirmed the presence of dysplasia. Our pilot data suggests that the p-BNC brush biopsy test recognized dysplastic oral epithelial cells in a brush biopsy sample of a FA patient.