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1.
Ann Biomed Eng ; 47(4): 1153-1164, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30710185

RESUMEN

This study analyzes the effects of the Rapha® system, which employs red light therapy (RLT) and a natural latex biomembrane in the healing of neuropathic ulcers associated with the diabetic foot. We conducted a randomized, controlled, blinded clinical trial with 15 participants that were divided into three groups (GI, GII and GIII): (i) Rapha® system application by the participant and a health professional at home, with clinical status evaluation every 2 weeks at the hospital (GI); (ii) standard protocol used in Brazil, performed by a health professional at the hospital (GII; control); and (iii) the Rapha® system applied by the participant at home and clinical status evaluation every 2 weeks at the hospital (GIII). We used image processing techniques on photographic recordings of the lesions, and several statistical tests were used to analyze the data, allowing for the comparison of the average results for all groups. The average healing rates of GI, GII, and GIII were 77.0, 51.4, and 80%, respectively. The granulation tissue evaluation indicated a higher efficacy in the tissue repair of lesions treated with the Rapha® system. In conclusion, the Rapha® system proved to be an effective healing system, even when self-applied at the patient's home.


Asunto(s)
Vendajes , Pie Diabético/terapia , Látex , Membranas Artificiales , Fototerapia , Cicatrización de Heridas , Anciano , Pie Diabético/patología , Pie Diabético/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad
2.
Physiol Meas ; 29(10): N59-70, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18812644

RESUMEN

Radiofrequency ablation has become an accepted treatment option of patients with primary and metastatic liver tumors. We propose an ablation electrode array consisting of 4-8 blade shaped electrodes arranged in a circular geometry for the treatment of large liver tumors. We developed a 3D code based on the finite difference method for evaluating the effect of different numbers of electrodes (4, 6 and 8) and electrode distance on lesion size. The configuration with six electrodes can ablate a volume of 70 x 70 x 40 mm(3) in approximately 5 min, with tissue temperature above 50 degrees C throughout the treatment volume. We then performed an experimental study in polyacrylamide gel in order to validate the theoretical results. The average temperature error between the simulation and the experiment was 3.8% at the center of the electrode array. This study shows that the proposed device potentially allows more rapid treatment of large tumors than current radiofrequency ablation devices.


Asunto(s)
Ablación por Catéter/instrumentación , Neoplasias Hepáticas/cirugía , Animales , Bovinos , Simulación por Computador , Conductividad Eléctrica , Electrodos , Análisis Numérico Asistido por Computador , Temperatura , Conductividad Térmica , Factores de Tiempo
3.
Artículo en Inglés | MEDLINE | ID: mdl-18002796

RESUMEN

This article presents a framework that allows the automated gathering of medical evidence, using a methodology based on Bayesian Networks (BN). For such purpose, system software and a programming methodology were developed. The proposed methodology is generic and can be applied to different contexts (application domains) were evidence gathering is executed in mobile devices.


Asunto(s)
Algoritmos , Inteligencia Artificial , Teorema de Bayes , Redes de Comunicación de Computadores , Monitoreo Ambulatorio/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Procesamiento de Señales Asistido por Computador , Computadoras de Mano , Diagnóstico por Computador/métodos , Interfaz Usuario-Computador
4.
Med Biol Eng Comput ; 44(4): 348-51, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16937176

RESUMEN

This work presents a study on the influence of the aqueous environment on the surface EMG (sEMG) signal recorded in bipolar montage from the abductor pollicis brevis muscle, when only the forearm is immersed in water. Ten men, 30.1+/-4.0 (mean +/- SD) years old, performed ten 2-s 40% MVC isometric contractions of the abductor pollicis brevis muscle in two controlled environments (air and water, at a temperature of 32 degrees C). They were always equipped with electrodes protected with a waterproof adhesive tape. No significant variations (paired Wilcoxon test) due to the environments were observed in the median frequency of the power spectrum (MDF) and in the root mean square (RMS) value of the sEMG signal. These results allow us to assess the methodological criteria to properly record sEMG signals in water and provide the basis to explain different findings obtained by other authors.


Asunto(s)
Electromiografía/normas , Músculo Esquelético/fisiología , Procesamiento de Señales Asistido por Computador , Adulto , Aire , Electromiografía/métodos , Antebrazo , Humanos , Contracción Isométrica , Masculino , Estadísticas no Paramétricas , Agua
5.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 1335-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17946039

RESUMEN

The objective of this work was the study and the development of techniques for acquiring and processing electromyographic signals that can be used for analysis of the behavior of electromyographic variables during fatiguing dynamic activities. Two of the techniques were the RMS value and the MPF, which are commonly used for the analysis of electromyographic signals measured during isometric contractions. A new technique, called MAEC, was proposed, based on the domain of the Wavelet transform. The results showed that the combination of the three techniques together with the protocol for recording electromyographic signals lead to a useful characterization of the behavior of electromygraphic variables.


Asunto(s)
Potenciales de Acción/fisiología , Algoritmos , Electromiografía/métodos , Contracción Muscular/fisiología , Fatiga Muscular/fisiología , Músculo Esquelético/fisiología , Procesamiento de Señales Asistido por Computador , Adulto , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 1089-92, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17946875

RESUMEN

This article presents an algorithm for compression of echocardiographic images. The algorithm is based on the JPEG algorithm and uses a fuzzy inference system to adapt the normalization process of the transformed coefficients through the analysis of the local characteristics of echocardiographic images. The images considered in this paper were acquired in actual echocardiography exams. The proposed encoder guarantees a maximum local signal-to-noise ratio, which is adapted to the characteristics of each sub-block of the image.


Asunto(s)
Algoritmos , Compresión de Datos/métodos , Ecocardiografía/métodos , Lógica Difusa , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
Acta bioquím. clín. latinoam ; 27(4): 459-62, dic. 1993. tab
Artículo en Español | LILACS | ID: lil-135776

RESUMEN

El test respiratorio utilizando urea marcada con C es un método no invasivo empleado desde 1988 para detectar la presencia de Helicobacter pylori en pacientes portadores de enfermedad ácido péptica. Este método ha demostrado una sensibilidad del 90,2 por ciento y especificidad de 83,8 por ciento . En el Centro de Medicina Nuclear de Guanabara fueron realizados 1.200 test respiratorios, de los cuales el 67 por ciento se reportaron positivos, realizándose nuevos controles después del tratamiento médico, con resultados negativos


Asunto(s)
Humanos , Pruebas Respiratorias , Gastritis/etiología , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/aislamiento & purificación , Radioisótopos de Carbono , Dióxido de Carbono , Estómago/microbiología , Etanolaminas , Cámaras gamma , Cámaras gamma/instrumentación , Cámaras gamma/normas , Gastritis/diagnóstico , Helicobacter pylori/fisiología , Reflujo Gastroesofágico/microbiología , Úlcera Péptica/diagnóstico , Úlcera Péptica/etiología , Ureasa , Ureasa/metabolismo , Ureasa/farmacología
8.
Acta bioquím. clín. latinoam ; 27(4): 459-62, dic. 1993. tab
Artículo en Español | BINACIS | ID: bin-24755

RESUMEN

El test respiratorio utilizando urea marcada con C es un método no invasivo empleado desde 1988 para detectar la presencia de Helicobacter pylori en pacientes portadores de enfermedad ácido péptica. Este método ha demostrado una sensibilidad del 90,2 por ciento y especificidad de 83,8 por ciento . En el Centro de Medicina Nuclear de Guanabara fueron realizados 1.200 test respiratorios, de los cuales el 67 por ciento se reportaron positivos, realizándose nuevos controles después del tratamiento médico, con resultados negativos(AU)


Asunto(s)
Humanos , Helicobacter pylori/aislamiento & purificación , Gastritis/etiología , Radioisótopos de Carbono/diagnóstico , Infecciones por Helicobacter/diagnóstico , Pruebas Respiratorias/métodos , Helicobacter pylori/fisiología , Ureasa/farmacología , Ureasa/metabolismo , Ureasa/diagnóstico , Gastritis/diagnóstico , Estómago/microbiología , Úlcera Péptica/diagnóstico , Úlcera Péptica/etiología , Reflujo Gastroesofágico/microbiología , Etanolaminas/diagnóstico , Dióxido de Carbono/diagnóstico , Cámaras gamma/instrumentación , Cámaras gamma/métodos , Cámaras gamma/normas
10.
Eur J Nucl Med ; 12(2): 91-5, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3525175

RESUMEN

The gastric emptying time is studied with 99mTC-DTPA-labeled mixed meal in 18 patients with chronic gastritis, all confirmed by endoscopic examination and biopsy. Emptying was slow in all such patients, but the intensity of symptomatology showed no correlation with gastric emptying half time.


Asunto(s)
Vaciamiento Gástrico , Gastritis/diagnóstico por imagen , Ácido Pentético , Tecnecio , Adolescente , Adulto , Enfermedad Crónica , Femenino , Gastritis/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía , Estómago/diagnóstico por imagen , Pentetato de Tecnecio Tc 99m , Factores de Tiempo
11.
J Neurobiol ; 16(5): 373-88, 1985 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-4045441

RESUMEN

These experiments in the slowly adapting stretch receptor of crayfish test the effects of brief length perturbations (i.e., pulses) when presented in isolation at different constant elongations or superimposed on trapezoidal stretches of different amplitudes. Within "in vivo" lengths, during static responses, perturbations reduced firing rates to below control values and, in extreme cases, could silence the receptor. This effect, or "down-step," was sustained, occurred above a threshold pulse amplitude and background stretch, and increased with both stimulus characteristics, but was not present during dynamic responses. Beyond "in vivo" lengths, and in a few cases within those limits but close to the extremes, the receptor was silent but perturbations could restore activity. Lengthening pulses were more effective than shortening ones in generating after-effects. Perturbations change, during indefinitively long periods, the receptor's length or static sensitivity acting as a negative feedback which tends to maintain the discharge rate within fixed values. Perturbations disclose marked nonlinearities, which suggest that the classical view of a proportional control in the reflex loop in which the receptor participates may not operate in natural conditions.


Asunto(s)
Potenciales de Acción , Adaptación Fisiológica , Astacoidea/fisiología , Mecanorreceptores/fisiología , Animales , Estimulación Eléctrica , Electrofisiología , Tiempo de Reacción , Factores de Tiempo
12.
J Nucl Med ; 22(4): 347-8, 1981 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6259305

RESUMEN

Chagas' disease is a serious protozoan infection affecting up to 20% of populations in some endemic areas. Myocarditis and cardiomyopathy occur in 50% of patients who go on to develop chronic Chagas' disease. We have studied a patient with no overt cardiac symptoms who revealed intense myocardial uptake of Tc-99m pyrophosphate. The significance of this finding in relation to early detection and progress of therapy is explored.


Asunto(s)
Enfermedad de Chagas/diagnóstico por imagen , Difosfatos , Tecnecio , Cardiomiopatía Chagásica/metabolismo , Cardiomiopatía Chagásica/prevención & control , Enfermedad de Chagas/metabolismo , Enfermedad de Chagas/terapia , Difosfatos/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía , Tecnecio/metabolismo , Factores de Tiempo
13.
Nucl Med (Stuttg) ; 15(1): 36-8, 1976 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1257047

RESUMEN

This case report demonstrates an hepatic amebic abscess by scintigraphy, utilizing a new radiopharmaceutical designed specifically for that purpose. The abscess is delineated as a positive lesion after twenty four hours. The agent 131I-labeled bromometronidazole, may prove to be specific for the diagnosis of these abscesses.


Asunto(s)
Absceso Hepático Amebiano/diagnóstico , Metronidazol/análogos & derivados , Cintigrafía , Adulto , Humanos , Técnicas In Vitro , Masculino
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