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1.
Sensors (Basel) ; 19(16)2019 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-31398948

RESUMEN

Cardiography is an indispensable element of health care. However, the accessibility of at-home cardiac monitoring is limited by device complexity, accuracy, and cost. We have developed a real-time algorithm for heart rate monitoring and beat detection implemented in a custom-built, affordable system. These measurements were processed from seismocardiography (SCG) and gyrocardiography (GCG) signals recorded at the sternum, with concurrent electrocardiography (ECG) used as a reference. Our system demonstrated the feasibility of non-invasive electro-mechanical cardiac monitoring on supine, stationary subjects at a cost of $100, and with the SCG-GCG and ECG algorithms decoupled as standalone measurements. Testing was performed on 25 subjects in the supine position when relaxed, and when recovering from physical exercise, to record 23,984 cardiac cycles at heart rates in the range of 36-140 bpm. The correlation between the two measurements had r2 coefficients of 0.9783 and 0.9982 for normal (averaged) and instantaneous (beat identification) heart rates, respectively. At a sampling frequency of 250 Hz, the average computational time required was 0.088 s per measurement cycle, indicating the maximum refresh rate. A combined SCG and GCG measurement was found to improve accuracy due to fundamentally different noise rejection criteria in the mutually orthogonal signals. The speed, accuracy, and simplicity of our system validated its potential as a real-time, non-invasive, and affordable solution for outpatient cardiac monitoring in situations with negligible motion artifact.


Asunto(s)
Electrocardiografía/métodos , Frecuencia Cardíaca/fisiología , Corazón/fisiología , Acelerometría , Algoritmos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/patología , Electrocardiografía/instrumentación , Humanos , Dispositivos Electrónicos Vestibles
2.
Analyst ; 142(10): 1746-1755, 2017 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-28443837

RESUMEN

Polymerase Chain Reaction (PCR) is a critical tool for biological research investigators but recently it also has been making a significant impact in clinical, veterinary and agricultural applications. Plasmonic PCR, which employs the very efficient heat transfer of optically irradiated metallic nanoparticles, is a simple and powerful methodology to drive PCR reactions. The scalability of next generation plasmonic PCR technology will introduce various forms of PCR applications ranging from small footprint portable point of care diagnostic devices to large footprint central laboratory multiplexing devices. In a significant advance, we have introduced a real time plasmonic PCR and explored the ability of ultra-fast cycling compatible with both label-free and fluorescence-based monitoring of amplicon production. Furthermore, plasmonic PCR has been substantially optimized to now deliver a 30 cycle PCR in 54 seconds, with a detectable product. The advances described here will have an immediate impact on the further development of the use of plasmonic PCR playing a critical role in rapid point of care diagnostics.

3.
Opt Lett ; 37(13): 2712-4, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22743504

RESUMEN

We report on the observation of a dynamical thermal effect in InGaAsP microtubes at telecom wavelengths. The microtubes are fabricated by releasing a strained semiconductor bilayer and are picked up by abruptly tapered optical fibers for subsequent coupling with adiabatically tapered optical fibers. As a result of absorption by InAs quantum dots embedded in the tube structure, these microtubes show dynamical thermal effects at wavelengths around 1525 nm and 1578 nm, while they are passive at longer wavelengths near 1634 nm. The photon absorption induced thermal effect is visualized by generating a pair of microbottles. The dynamical thermal effect can be avoided or exploited for passive or active applications by utilizing appropriate resonance wavelengths.

4.
Analyst ; 137(19): 4475-81, 2012 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-22871797

RESUMEN

A plasmonic heating method for the polymerase chain reaction is demonstrated by the amplification of a section of the human androgen receptor gene. The thermocycler has a simple low-cost design, demonstrates excellent temperature stability and represents the first practical demonstration of plasmonic thermocycling.


Asunto(s)
ADN/análisis , Reacción en Cadena de la Polimerasa , Receptores Androgénicos/genética , Oro/química , Humanos , Nanopartículas del Metal/química , Temperatura
5.
Opt Lett ; 36(1): 46-8, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21209682

RESUMEN

A surface plasmon biosensing technique based on real-time measurement of the spectro-angular reflectance spectrum of a gold surface is presented. A significant improvement in refractive index resolution and drift compensation has been achieved for the spectro-angular technique to demonstrate a biosensing platform that is, in addition, applicable to plasmonic bandgap measurements. Instrumental improvements are detailed and constants for the model bovine serum albumin (BSA):oxacillin bioassay are presented.


Asunto(s)
Análisis Espectral/métodos , Resonancia por Plasmón de Superficie/métodos , Animales , Bovinos , Oxacilina/metabolismo , Albúmina Sérica Bovina/metabolismo , Análisis Espectral/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Factores de Tiempo
6.
CRISPR J ; 1: 414-430, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-31021244

RESUMEN

Homology-directed repair (HDR) induced by site specific DNA double-strand breaks with CRISPR-Cas9 is a precision gene editing approach that occurs at low frequency in comparison to indel forming non-homologous end joining (NHEJ). In order to obtain high HDR percentages in mammalian cells, we engineered a Cas9 protein fused to a monoavidin domain to bind biotinylated donor DNA. In addition, we used the cationic polymer, polyethylenimine, to deliver Cas9-donor DNA complexes into cells. Improved HDR percentages of up to 90% in three loci tested (CXCR4, EMX1, and TLR) in standard HEK293T cells were observed. Our results suggest that donor DNA biotinylation and Cas9-donor conjugation in addition to delivery influence HDR efficiency.

7.
PLoS One ; 11(2): e0149723, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26901566

RESUMEN

BACKGROUND: The incidence of papillary thyroid carcinoma (PTC) has risen steadily over the past few decades as well as the recurrence rates. It has been proposed that targeted ablative physical therapy could be a therapeutic modality in thyroid cancer. Targeted bio-affinity functionalized multi-walled carbon nanotubes (BioNanofluid) act locally, to efficiently convert external light energy to heat thereby specifically killing cancer cells. This may represent a promising new cancer therapeutic modality, advancing beyond conventional laser ablation and other nanoparticle approaches. METHODS: Thyroid Stimulating Hormone Receptor (TSHR) was selected as a target for PTC cells, due to its wide expression. Either TSHR antibodies or Thyrogen or purified TSH (Thyrotropin) were chemically conjugated to our functionalized Bionanofluid. A diode laser system (532 nm) was used to illuminate a PTC cell line for set exposure times. Cell death was assessed using Trypan Blue staining. RESULTS: TSHR-targeted BioNanofluids were capable of selectively ablating BCPAP, a TSHR-positive PTC cell line, while not TSHR-null NSC-34 cells. We determined that a 2:1 BCPAP cell:α-TSHR-BioNanofluid conjugate ratio and a 30 second laser exposure killed approximately 60% of the BCPAP cells, while 65% and >70% of cells were ablated using Thyrotropin- and Thyrogen-BioNanofluid conjugates, respectively. Furthermore, minimal non-targeted killing was observed using selective controls. CONCLUSION: A BioNanofluid platform offering a potential therapeutic path for papillary thyroid cancer has been investigated, with our in vitro results suggesting the development of a potent and rapid method of selective cancer cell killing. Therefore, BioNanofluid treatment emphasizes the need for new technology to treat patients with local recurrence and metastatic disease who are currently undergoing either re-operative neck explorations, repeated administration of radioactive iodine and as a last resort external beam radiation or chemotherapy, with fewer side effects and improved quality of life.


Asunto(s)
Anticuerpos Antineoplásicos/farmacología , Carcinoma/terapia , Sistemas de Liberación de Medicamentos/métodos , Terapia por Luz de Baja Intensidad/métodos , Nanotubos de Carbono/química , Neoplasias de la Tiroides/terapia , Tirotropina Alfa/farmacología , Animales , Carcinoma Papilar , Línea Celular Tumoral , Humanos , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/metabolismo , Receptores de Tirotropina/agonistas , Receptores de Tirotropina/metabolismo , Cáncer Papilar Tiroideo
8.
9.
Rev Sci Instrum ; 85(9): 093107, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25273707

RESUMEN

Surface plasmon resonance (SPR) sensing is one of the most widely used methods to implement biosensing due to its sensitivity and capacity for label-free detection. Whilst most commercial SPR sensors operate in the angular regime, it has recently been shown that an increase in sensitivity and a greater robustness against noise can be achieved by measuring the reflectivity when varying both the angle and wavelength simultaneously, in a so-called spectro-angular SPR biosensor. A single value decomposition method is used to project the two-dimensional spectro-angular reflection signal onto a basis set and allow the image obtained from an unknown refractive index sample to be compared very accurately with a pre-calculated reference set. Herein we demonstrate that a previously reported system operated in the near infra-red has a lower detection limit when operating in the visible spectrum due to the improved spatial resolution and numerical precision of the image sensor. The SPR biosensor presented here has an experimental detection limit of 9.8 × 10(-7) refractive index unit. To validate the system as a biosensor, we also performed the detection of synthetic RNA from pathogenic Legionella pneumophila with the developed biosensing platform.


Asunto(s)
Espectrofotometría Infrarroja/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Diseño de Equipo
10.
J Clin Endocrinol Metab ; 98(12): 4599-605, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24217901

RESUMEN

CONTEXT: Struma ovarii is an uncommon monodermal teratoma in which thyroid tissue is the predominant element. Malignant transformation of struma ovarii is an even rarer occurrence. CASE PRESENTATION: We describe a 42-year-old woman who underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy for a symptomatic left pelvic mass. Histology revealed malignant struma ovarii with classical papillary thyroid carcinoma expression. Ultrasonography of the cervical neck showed thyroid micronodules and a dominant 1-cm nodule in the left thyroid lobe. As the ovarian tumor was large, the patient underwent a total thyroidectomy with the intention of administering ¹³¹I therapy in an adjuvant setting. Histology of the cervical thyroid gland revealed bilateral multifocal papillary thyroid carcinoma with extrathyroidal extension and perithyroidal lymph node metastasis. METHODS: Morphological (microscopy), immunohistochemical (Hector Battifora mesothelial cell 1, cytokeratin-19, galectin-3), and molecular (BRAF V600E, RAS, RET-PTC) characteristics and clonality analysis of the cervical thyroid and ovarian tumors were explored to distinguish them as separate malignancies. RESULTS: The thyroid-type tumors from the cervical gland and ovary were discordant in terms of tissue histology and level of cytokeratin-19 expression. The clinical features and tumor profile results supported the independent existence of these two embryologically related, although topographically distinct, malignancies. CONCLUSION: Our findings provided support for synchronous, albeit distinct, primary tumors in the ovary and cervical thyroid. "Field cancerization" and early genomic instability may explain multifocality in all thyroid-type tissue. In this regard, patients with malignant struma ovarii should undergo imaging of their thyroid gland for coexisting disease and thyroidectomy recommended for suspected malignancy or in preparation for radioiodine therapy.


Asunto(s)
Carcinoma Papilar/cirugía , Neoplasias Primarias Secundarias/cirugía , Neoplasias Ováricas/cirugía , Estruma Ovárico/cirugía , Neoplasias de la Tiroides/cirugía , Nódulo Tiroideo/cirugía , Adulto , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patología , Carcinoma Papilar/radioterapia , Carcinoma Papilar/secundario , Femenino , Humanos , Radioisótopos de Yodo/uso terapéutico , Queratina-19/metabolismo , Metástasis Linfática , Proteínas de Neoplasias/metabolismo , Estadificación de Neoplasias , Neoplasias Primarias Secundarias/metabolismo , Neoplasias Primarias Secundarias/patología , Neoplasias Primarias Secundarias/secundario , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Radiofármacos/uso terapéutico , Radioterapia Adyuvante , Estruma Ovárico/metabolismo , Estruma Ovárico/patología , Estruma Ovárico/secundario , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/radioterapia , Nódulo Tiroideo/metabolismo , Nódulo Tiroideo/patología , Nódulo Tiroideo/radioterapia , Resultado del Tratamiento , Carga Tumoral/efectos de los fármacos , Carga Tumoral/efectos de la radiación
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