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1.
Phys Ther ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38742841

RESUMEN

OBJECTIVE: The objective was to determine the validity of the Targeted Motor Control (TMC) screening tool with the Neurosensory Motor Developmental Assessment (NSMDA) in 4-year-old children. METHODS: In this single cohort observational study, children (3 years 9 months to 4 years 5 months) completed the TMC and the NSMDA in a randomized order 5 to 14 days apart. RESULTS: Seventy-six children (mean age = 4 years 2 months; SD = 2.5 months; n = 35 male) completed both assessments. Forty-two children performed within the normal range on the NSMDA. There were significant and positive moderate correlations between item totals overall and for each area on the NSMDA and the TMC (r = 0.40 to 0.61) and between the NSMDA functional grade for each area and the corresponding TMC areas (r = 0.47 to 0.67). However, the correlation between the NSMDA sensorimotor functional grade and the TMC sensory score was significant but low and positive (r = 0.35). The optimal cut-off score for detecting children at risk of atypical development on the TMC was a score of <9 (n = 42) (sensitivity = 82.4%; specificity = 66.7%) with a positive likelihood ratio of 2.47 (95% CI = 1.57 to 3.89) and a negative likelihood ratio of 0.26 (95% CI = 0.12 to 0.56). CONCLUSIONS: The TMC is a valid screening tool to identify 4-year-old children at risk of motor delay. IMPACT: Early identification of developmental concerns using a validated screening tool is recommended. The TMC is a valid performance-based screening tool that can be used to identify children at risk of atypical motor development who would benefit from further developmental assessment so that, if indicated, timely intervention can be implemented.

2.
Micromachines (Basel) ; 14(3)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36985075

RESUMEN

Nanoscale fluorescence emitters are efficient for measuring biomolecular interactions, but their utility for applications requiring single-unit observations is constrained by the need for large numerical aperture objectives, fluorescence intermittency, and poor photon collection efficiency resulting from omnidirectional emission. Photonic crystal (PC) structures hold promise to address the aforementioned challenges in fluorescence enhancement. In this review, we provide a broad overview of PCs by explaining their structures, design strategies, fabrication techniques, and sensing principles. Furthermore, we discuss recent applications of PC-enhanced fluorescence-based biosensors incorporated with emerging technologies, including nucleic acids sensing, protein detection, and steroid monitoring. Finally, we discuss current challenges associated with PC-enhanced fluorescence and provide an outlook for fluorescence enhancement with photonic-plasmonics coupling and their promise for point-of-care biosensing as well monitoring analytes of biological and environmental relevance. The review presents the transdisciplinary applications of PCs in the broad arena of fluorescence spectroscopy with broad applications in photo-plasmonics, life science research, materials chemistry, cancer diagnostics, and internet of things.

3.
Biosens Bioelectron ; 228: 115197, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36905862

RESUMEN

Label-free detection and digital counting of nanometer-scaled objects such as nanoparticles, viruses, extracellular vesicles, and protein molecules enable a wide range of applications in cancer diagnostics, pathogen detection, and life science research. Here, we report the design, implementation, and characterization of a compact Photonic Resonator Interferometric Scattering Microscope (PRISM) designed for point-of-use environments and applications. The contrast of interferometric scattering microscopy is amplified through a photonic crystal surface, upon which scattered light from an object combines with illumination from a monochromatic source. The use of a photonic crystal substrate for interferemetric scattering microscopy results in reduced requirements for high-intensity lasers or oil-immersion objectives, thus opening a pathway toward instruments that are more suitable for environments outside the optics laboratory. The instrument incorporates two innovative elements that facilitate operation on a desktop in ordinary laboratory environments by users that do not have optics expertise. First, because scattering microscopes are extremely sensitive to vibration, we incorporated an inexpensive but effective solution of suspending the instrument's main components from a rigid metal framework using elastic bands, resulting in an average of 28.7 dBV reduction in vibration amplitude compared to an office desk. Second, an automated focusing module based on the principle of total internal reflection maintains the stability of image contrast over time and spatial position. In this work, we characterize the system's performance by measuring the contrast from gold nanoparticles with diameters in the 10-40 nm range and by observing various biological analytes, including HIV virus, SARS-CoV-2 virus, exosome, and ferritin protein.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanopartículas del Metal , Humanos , Microscopía , Oro/química , Técnicas Biosensibles/métodos , COVID-19/diagnóstico , SARS-CoV-2
4.
Biosensors (Basel) ; 13(2)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36832064

RESUMEN

The ability to self-test for HIV is vital to preventing transmission, particularly when used in concert with HIV biomedical prevention modalities, such as pre-exposure prophylaxis (PrEP). In this paper, we review recent developments in HIV self-testing and self-sampling methods, and the potential future impact of novel materials and methods that emerged through efforts to develop more effective point-of-care (POC) SARS-CoV-2 diagnostics. We address the gaps in existing HIV self-testing technologies, where improvements in test sensitivity, sample-to-answer time, simplicity, and cost are needed to enhance diagnostic accuracy and widespread accessibility. We discuss potential paths toward the next generation of HIV self-testing through sample collection materials, biosensing assay techniques, and miniaturized instrumentation. We discuss the implications for other applications, such as self-monitoring of HIV viral load and other infectious diseases.


Asunto(s)
COVID-19 , Infecciones por VIH , Humanos , Autoevaluación , SARS-CoV-2 , Pruebas en el Punto de Atención
5.
J Neurochem ; 164(5): 613-623, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36420597

RESUMEN

While the illicit use and misuse of stimulants like cocaine and methylphenidate (MP) has increased, there remains no FDA-approved treatments for psychostimulant use disorders (PSUD). Oxytocin (OT) has shown promise as a potential pharmacotherapy for PSUD. Dopamine (DA) neurotransmission plays a significant role in PSUD. We have recently shown that OT blunts the reinforcing effects of MP but, surprisingly, enhanced MP-induced stimulation of DA levels. Such effects have been suggested as a result of activation of OT receptors or, alternatively, could be mediated by direct actions of OT on MP blockade of the DA transporter. Here, we employed fast scan cyclic voltammetry (FSCV) to investigate the effects of systemic OT on MP-induced changes in the dynamics of DA, phasic release and uptake, in the nucleus accumbens shell (NAS) of Sprague-Dawley rats. We also tested the systemic effects of an antagonist of OT receptors, atosiban, to counteract the OT enhancement of dopaminergic effects of MP under microdialysis procedures in the NAS in rats. Administration of OT alone (2 mg/kg; i.p.) did not significantly modify evoked NAS DA dynamics measured by FSCV, and when administered 10 min before MP (0.1, 0.3, 1.0 mg/kg; i.v.), OT did not potentiate MP-induced increases in phasic DA release and did not alter DA clearance rate, suggesting no direct interactions of OT with the MP-induced blockade of DA uptake. Also, OT alone did not elicit significant changes in tonic, extracellular NAS DA levels measured by microdialysis. However, consistent with previous studies, we observed that OT pretreatments (2 mg/kg; i.p.) potentiated MP-induced (0.1, 0.3, 1.0 mg/kg; i.v.) efflux of extracellular NAS DA levels. This effect was abolished when rats were pretreated with atosiban (2 mg/kg; i.p.), suggesting that OT receptors mediate this OT action. Overall, our results suggest that OT receptors mediated OT potentiation of MP-induced stimulation of extracellular NAS DA levels, likely driven by modulation of DA receptor signaling pathways, without affecting MP blockade of DAT.


Asunto(s)
Estimulantes del Sistema Nervioso Central , Metilfenidato , Ratas , Animales , Metilfenidato/metabolismo , Metilfenidato/farmacología , Dopamina/metabolismo , Oxitocina/metabolismo , Oxitocina/farmacología , Receptores de Oxitocina/metabolismo , Ratas Sprague-Dawley , Estimulantes del Sistema Nervioso Central/farmacología , Núcleo Accumbens
6.
bioRxiv ; 2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36561182

RESUMEN

Label-free detection and digital counting of nanometer-scaled objects such as nanoparticles, viruses, extracellular vesicles, and protein molecules enable a wide range of applications in cancer diagnostics, pathogen detection, and life science research. The contrast of interferometric scattering microscopy is amplified through a photonic crystal surface, upon which scattered light from an object combines with illumination from a monochromatic plane wave source. The use of a photonic crystal substrate for interference scattering microscopy results in reduced requirements for high-intensity lasers or oil-immersion objectives, thus opening a pathway toward instruments that are more suitable for environments outside the optics laboratory. Here, we report the design, implementation, and characterization of a compact Photonic Resonator Interferometric Scattering Microscope (PRISM) designed for point-of-use environments and applications. The instrument incorporates two innovative elements that facilitate operation on a desktop in ordinary laboratory environments by users that do not have optics expertise. First, because scattering microscopes are extremely sensitive to vibration, we incorporated an inexpensive but effective solution of suspending the instrument's main components from a rigid metal framework using elastic bands, resulting in an average of 28.7 dBV reduction in vibration amplitude compared to an office desk. Second, an automated focusing module based on the principle of total internal reflection maintains the stability of image contrast over time and spatial position, facilitating automated data collection. In this work, we characterize the system's performance by measuring the contrast from gold nanoparticles with diameters in the 10-40 nm range and by observing various biological analytes, including HIV virus, SARS-CoV-2 virus, exosomes, and ferritin protein.

7.
Analyst ; 147(17): 3838-3853, 2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-35726910

RESUMEN

Rapid, simple, inexpensive, accurate, and sensitive point-of-care (POC) detection of viral pathogens in bodily fluids is a vital component of controlling the spread of infectious diseases. The predominant laboratory-based methods for sample processing and nucleic acid detection face limitations that prevent them from gaining wide adoption for POC applications in low-resource settings and self-testing scenarios. Here, we report the design and characterization of an integrated system for rapid sample-to-answer detection of a viral pathogen in a droplet of whole blood comprised of a 2-stage microfluidic cartridge for sample processing and nucleic acid amplification, and a clip-on detection instrument that interfaces with the image sensor of a smartphone. The cartridge is designed to release viral RNA from Zika virus in whole blood using chemical lysis, followed by mixing with the assay buffer for performing reverse-transcriptase loop-mediated isothermal amplification (RT-LAMP) reactions in six parallel microfluidic compartments. The battery-powered handheld detection instrument uniformly heats the compartments from below, and an array of LEDs illuminates from above, while the generation of fluorescent reporters in the compartments is kinetically monitored by collecting a series of smartphone images. We characterize the assay time and detection limits for detecting Zika RNA and gamma ray-deactivated Zika virus spiked into buffer and whole blood and compare the performance of the same assay when conducted in conventional PCR tubes. Our approach for kinetic monitoring of the fluorescence-generating process in the microfluidic compartments enables spatial analysis of early fluorescent "bloom" events for positive samples, in an approach called "Spatial LAMP" (S-LAMP). We show that S-LAMP image analysis reduces the time required to designate an assay as a positive test, compared to conventional analysis of the average fluorescent intensity of the entire compartment. S-LAMP enables the RT-LAMP process to be as short as 22 minutes, resulting in a total sample-to-answer time in the range of 17-32 minutes to distinguish positive from negative samples, while demonstrating a viral RNA detection as low as 2.70 × 102 copies per µl, and a gamma-irradiated virus of 103 virus particles in a single 12.5 µl droplet blood sample.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Humanos , Microfluídica , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN Viral/genética , Sensibilidad y Especificidad , Teléfono Inteligente , Instrumentos Quirúrgicos , Virus Zika/genética , Infección por el Virus Zika/diagnóstico
8.
Front Neurosci ; 15: 656475, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34121988

RESUMEN

The number of individuals affected by psychostimulant use disorder (PSUD) has increased rapidly over the last few decades resulting in economic, emotional, and physical burdens on our society. Further compounding this issue is the current lack of clinically approved medications to treat this disorder. The dopamine transporter (DAT) is a common target of psychostimulant actions related to their use and dependence, and the recent availability of atypical DAT inhibitors as a potential therapeutic option has garnered popularity in this research field. Modafinil (MOD), which is approved for clinical use for the treatment of narcolepsy and sleep disorders, blocks DAT just like commonly abused psychostimulants. However, preclinical and clinical studies have shown that it lacks the addictive properties (in both behavioral and neurochemical studies) associated with other abused DAT inhibitors. Clinical availability of MOD has facilitated its off-label use for several psychiatric disorders related to alteration of brain dopamine (DA) systems, including PSUD. In this review, we highlight clinical and preclinical research on MOD and its R-enantiomer, R-MOD, as potential medications for PSUD. Given the complexity of PSUD, we have also reported the effects of MOD on psychostimulant-induced appearance of several symptoms that could intensify the severity of the disease (i.e., sleep disorders and impairment of cognitive functions), besides the potential therapeutic effects of MOD on PSUD.

9.
Sci Rep ; 9(1): 12701, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31481686

RESUMEN

Marijuana is listed as a Schedule I substance under the American Controlled Substances Act of 1970. As more U.S. states and countries beyond the U.S. seek legalization, demands grow for identifying individuals driving under the influence (DUI) of marijuana. Currently no roadside DUI test exists for determining marijuana impairment, thus the merit lies in detecting the primary and the most sought psychoactive compound tetrahydrocannabinol (THC) in marijuana. Salivary THC levels are correlated to blood THC levels making it a non-invasive medium for rapid THC testing. Affinity biosensing is leveraged for THC biomarker detection through the chemical reaction between target THC and THC specific antibody to a measure signal output related to the concentration of the targeted biomarker. Here, we propose a novel, rapid, electrochemical biosensor for the detection of THC in saliva as a marijuana roadside DUI test with a lower detection limit of 100 pg/ml and a dynamic range of 100 pg/ml - 100 ng/ml in human saliva. The developed biosensor is the first of its kind to utilize affinity-based detection through impedimetric measurements with a rapid detection time of less than a minute. Fourier transform infrared spectroscopy analysis confirmed the successful immobilization of the THC immobilization assay on the biosensing platform. Zeta potential studies provided information regarding the stability and the electrochemical behavior of THC immunoassay in varying salivary pH buffers. We have demonstrated stable, dose dependent biosensing in varying salivary pH's. A binary classification system demonstrating a high general performance (AUC = 0.95) was employed to predict the presence of THC in human saliva. The biosensor on integration with low-power electronics and a portable saliva swab serves as a roadside DUI hand-held platform for rapid identification of THC in saliva samples obtained from human subjects.


Asunto(s)
Técnicas Biosensibles , Dronabinol/análisis , Técnicas Electroquímicas , Abuso de Marihuana , Saliva/metabolismo , Detección de Abuso de Sustancias , Anticuerpos/química , Humanos , Inmunoensayo , Abuso de Marihuana/diagnóstico , Abuso de Marihuana/metabolismo
10.
Med Teach ; 40(2): 212-213, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29022462
11.
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