Neuroprotective Effect of Isobenzofuranones on Hydrogen Peroxide-Mediated Redox Imbalance in Primary Cultures of Hippocampal Neurons

Abstract In live organisms, there is a balance between the production of reactive oxygen species (ROS) and their neutralization. The increased level of these species leads to a condition called redox imbalance. The aim of this study was to evaluate the protective action of isobenzofuranones in primary cultures of hippocampal neurons subjected to redox imbalance. To accomplish this, MTT and LIVE/DEAD assays were initially performed. In the cultures pretreated with isobenzofuranones 1 and 2, there was a higher number of live cells when compared to that in the untreated ones. Regarding redox imbalance, there was a significant increase in the intracellular levels of ROS. The cultures pretreated with isobenzofuranones showed a reduction in ROS levels. Lipid peroxidation caused by oxidative damage was significantly reduced in the cultures pretreated with isobenzofuranones 1 and 2. Taken together, these data show the ability of isobenzofuranones 1 and 2 to significantly minimize cytotoxicity, cell death, intracellular levels of ROS and lipid peroxidation induced by redox imbalance. These results suggest that isobenzofuranones 1 and 2 represent a possible alternative therapy for the neurodegenerative disturbances that are triggered by ROS production increases.

T-lymphocyte-expressing inflammatory cytokines underlie persistence of proteinuria in children with idiopathic nephrotic syndrome / Os linfócitos T que expressam citocinas inflamatórias são subjacentes à persistência de proteinúria em crianças com síndrome nefrótica idiopática

Abstract Objective: There is evidence of an important role of immune system changes in the triggering and maintenance of idiopathic nephrotic syndrome (INS). The aim of this study was to investigate the expression of cytokines in lymphocyte populations of patients with INS in comparison to healthy individuals, according to proteinuria. Methods: This cross-sectional study included 44 patients with INS and eight healthy children, matched for age and sex (controls). Patients were subdivided according to proteinuria: persistent proteinuria or partial remission (PP ≥ 300 mg/24 h, n = 17) and low proteinuria or complete remission (LP < 300 mg/24 h, n = 27). Ex vivo analysis of peripheral blood leukocytes by flow cytometry was performed using surface markers for T-lymphocytes, TCD4, TCD8, natural killer (NK) cells, NKT, and B-lymphocytes. Frequencies of intracellular cytokines were analyzed in these cells. Results: The frequencies of B-lymphocytes, NK cells, and NKT cells were lower in INS than in controls, whereas INS patients had a higher frequency of CD4+tumor necrosis factor (TNF)-α+ cells than controls. Cytotoxic-T-lymphocytes expressing IFN-γ were lower in INS than in controls. Patients with PP showed higher frequencies of CD4-T-lymphocytes expressing IFN-γ and TNF-α than controls. CD8-lymphocytes expressing TNF-α were increased in PP group when compared with LP and controls, while CD8+interferon (IFN)-γ+ cells were lower than in LP and in controls. Conclusion: Regardless the level of proteinuria, INS patients had increased expression of TNF-α in CD4-lymphocytes and reduced expression of IFN-γ in CD8-lymphocytes. Persistence of proteinuria was associated with higher levels of inflammatory markers.

Resumo Objetivo Há comprovação do importante papel das alterações no sistema imunológico no desencadeamento e manutenção da síndrome nefrótica idiopática (SNI). O objetivo deste estudo foi investigar a expressão das citocinas em populações de linfócitos de pacientes com SNI em comparação a indivíduos saudáveis e de acordo com a proteinúria. Métodos Este estudo transversal incluiu 44 pacientes com SNI e oito crianças saudáveis, pareados por idade e sexo (controles). Os pacientes foram subdivididos de acordo com a proteinúria: proteinúria persistente ou remissão parcial (PP ≥ 300 mg/24 h, n = 17) e proteinúria baixa ou remissão completa (PB < 300 mg/24 h, n = 27). A análise ex vivo de leucócitos no sangue periférico por citometria de fluxo foi feita utilizando marcadores de superfície para linfócitos T, TCD4, TCD8, células natural killer (NK), linfócitos NKT e B. As frequências das citocinas intracelulares foram analisadas nessas células. Resultados A frequência dos linfócitos B, células NK e células NKT foi menor em pacientes com SNI do que nos controles, ao passo que os pacientes com SNI apresentaram maior frequência de células CD4+fator de necrose tumoral (TNF)-α+ do que nos controles. Os linfócitos T citotóxicos que expressam interferon (IFN)-γ foram menores nos pacientes com SNI do que nos controles. Os pacientes com PP mostraram maiores frequências de linfócitos T CD4 que expressam IFN-γ e TNF-α que os controles. Os linfócitos CD8 que expressam TNF-α apresentaram aumento no grupo com PP, em comparação aos com PB e os controles, apesar de as células CD8+IFN-γ+ serem mais baixas nos pacientes com PB e nos controles. Conclusão Com relação ao nível de proteinúria, os pacientes com SNI apresentaram aumento na expressão de TNF-α nos linfócitos CD4 e expressão reduzida de IFN-γ nos linfócitos CD8. A persistência da proteinúria foi associada a maiores níveis de marcadores inflamatórios.

Exploring cortical bone density through the ultrasound integrated reflection coefficient / Densidade óssea cortical analisada pelo coeficiente de reflexão ultrassônica

ABSTRACT Objective: This work evaluates the relationship between ultrasonic reflection and bone density from fourteen cylindrical bovine cortical bone samples (3.0-cm thick). Methods: Twenty US reflection signals per sample were acquired along the bone surface (2.0-mm step). The Integrated Reflection Coefficient (IRC) from each signal was compared to Quantitative Computed Tomography (QCT). Results: Seven IRC and QCT curves presented Pearson's Correlation R-values above 0.5. For weak correlation curves, QCT and IRC showed similar trends in several segments. Conclusion: IRC was sensitive to bone density variation. Level of Evidence: Experimental Study, Investigating a Diagnostic Test.

RESUMO Objetivo: Este estudo avalia a relação entre a reflexão ultrassônica e a densidade óssea de 14 amostras cilíndricas de osso cortical bovino (3,0 cm de espessura). Métodos: Foi realizada a aquisição de 20 sinais de reflexão ultrassônica por amostra (passo de 2,0 mm), ao longo da superfície óssea. O Coeficiente de Reflexão Integrado (IRC) de cada sinal foi comparado por Tomografia Computadorizada Quantitativa (QCT). Resultados: Sete curvas de IRC e QCT apresentaram valor de Correlação R de Pearson acima de 0,5. Para curvas de correlação fraca, QCT e IRC apresentaram tendências semelhantes em vários segmentos. Conclusão: O IRC foi sensível à variação da densidade óssea. Nível de evidência: Estudo Experimental, Investigação de Exame Diagnóstico.

Mean scatterer space estimation from ultrasound signals combining singular spectral analysis and entropy

AbstractIntroduction: Ultrasound (US) is a nonionizing radiation capable of real time imaging at low cost. Its most attractive application is quantitative tissue characterization with the objective of differentiating normal tissues from diseased tissues. In this study, an automated method using singular spectrum analysis (SSA) to estimate the mean scatterer space (MSS) of US signals is proposed. Methods Entropy was used to determine the optimal number of components for the SSA. Subsequently, this number was compared with the results using a fixed number of components. A method based on the spectrum of the original signal was also used for comparison. The method was evaluated by using 24,000 simulated US signals, i.e., echoes and jitters backscattered from samples with different ratios of regular-to-irregular structure, as well as with 152 signals obtained from a phantom made of nylon wires. Results For the simulated signals, the proposed method for estimating the MSS presented results similar to the other methods that were tested. However, the magnitude-of-the-spectrum method loses the phase information, and hence, does not allow the characterization of irregular structures. For the signals recorded from the phantom, the methods using SSA and entropy achieved better results. Conclusion In this study, the combination of SSA with entropy to estimate the MSS of a periodic or quasi-periodic medium was proposed. The proposed method achieved similar or better results compared with two other methods found in the scientific literature. The novelty of the proposed method is the application of entropy as a quantitative criterion for selecting the SSA periodic components, allowing it to become independent of heuristic criteria.

Evaluation of gloves as a water bag coupling agent for therapeutic ultrasound

Abstract Introduction Therapeutic ultrasound (TUS) is a widespread modality in physiotherapy, and the water bag technique is a coupling method employed in the presence of anatomical irregularities in the treatment area. The aim of the present study is to evaluate the acoustic attenuation of the water bag and its effectiveness as a TUS coupling agent. Methods The rated output powers (ROPs) of the TUS equipment were evaluated based on IEC 61689. Then, a radiation force balance was used to measure ROP with and without a water bag (latex and nitrile gloves filled with deionized water) between a TUS transducer and the cone-shaped target of the balance. Each experiment was performed five times for each nominal power (0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, and 7.0 W) and in the following configurations: without the water bag (A), with nitrile gloves and with (B) and without (C) a height controller, and latex gloves with (D) and without (E) height controller. ROPs obtained in different media were compared. Results The highest relative error of ROP was 16.72% for 0.5 W. Although the power values of the equipment were within the range recommended by IEC, there was a significant difference between the ROP values measured with A and with B, C and D. Conclusion As intensity differences below 0.5 W/cm2 are considered clinically not relevant, conditions A, B, C, D, or E can be used interchangeably.

Influência da estabilização segmentar core na dor e funcionalidade da coluna lombar / Influence of segmental core stabilization in pain and spinal lumbar functionality

Atualmente a dor lombar descreve-se como uma dor limitante que resulta em incapacidade funcional. Dentre as técnicas de intervenção terapêutica, destaca-se o fortalecimento segmentar do core. O objetivo do presente trabalho é analisar o efeito do fortalecimento do core na dor e na função da coluna lombar. Trata-se de um estudo clínico de intervenção, desenvolvido nas Clínicas Integradas Guairacá, com 12 indivíduos, de ambos os sexos, com média de idade de 49,2 ± 6,6 anos, que apresentaram dor lombar inespecífica. Foram incluídos no estudo indivíduos que conseguissem realizar os exercícios de estabilização segmentar do core. Para quantificar a dor da coluna lombar, utilizou-se a Escala Visual Analógica da Dor (EVAD) e para avaliação da função lombar foi aplicado o Índice Funcional de Oswestry (IFO). Para a análise estatística, utilizou-se o software BioEstat 5.3. Para testar a normalidade dos dados, foi utilizado o teste de d'Agostino e para testar a significância dos resultados, utilizou-se o teste T-Student, com significância de p ? 0,05. Na comparação pré e pós-intervenção dos valores do IFO, observou-se uma redução estatisticamente significante p = 0,0012. Na comparação pré e pós-intervenção dos valores EVAD observou-se uma redução estatisticamente significante p = 0,0001. Contudo, o presente trabalho demonstra que a aplicação dos exercícios de estabilização lombar core apresenta-se efetiva na melhora da dor e da função lombar. (AU)

Currently low back pain is described as a limit pain that results in functional disability. Among the techniques of therapeutic therapy, the segmental strengthening of the "core" is highlighted. The aim of the present study is to analyze the effect of core strengthening on pain and lumbar spine function. The present study is a clinical intervention study, developed in the Guairacá Integrated Clinics, with 12 individuals, of the both sexes, mean age 49.2 ± 6.6 years, with nonspecific low back pain. There are also included in the study individuals that were able to perform segmental stabilization exercises of the core. To quantify the pain of the lumbar spine, the Visual Analog Pain Scale (VAS) was used to quantify the pain of lumbar spine, and for evaluation of the lumbar function was applied the Oswestry Functional Index (OFI). For statistical analysis we used the software BioEstat 5.3. To test the normality of data was used the D'Agostino Test, and to test the significance of the results the Student's T-test was applied, with significance of p ? 0.05. By comparing the test before and after intervention of OFI values, a statistically significant reduction was observed (p = 0.0012). Before and after intervention of VAS values, a statistically significant reduction was observed (p = 0.0001). However, the present study shows that the lumbar stabilization exercises core are effective in the improvement of pain and lumbar function. (AU)

Comparative study of periodicity estimation methods using ultrasonic signals

Abstract Introduction Various signal-processing techniques have been proposed to extract quantitative information about internal structures of tissues from the original radio frequency (RF) signals instead of an ultrasound image. The quantifiable parameter called the mean scatterer spacing (MSS) can be useful to detect changes in the quasi-periodic microstructure of tissues such as the liver or the spleen, using ultrasonic signals. Methods We evaluate and compare the performance of three classic methods of spectral estimation to calculate the MSS without operator intervention: Tufts-Kumaresan, SAC (Spectral Autocorrelation) and MUSIC (MUltiple SIgnal Classification). Initially the evaluations were performed with 10,000 signals simulated from a model in which the variables of interest are controlled, and then, real signals from sponge phantoms were used. Results For the simulated signals, the performance of all three methods decreased with increasing Ad or jitter levels. For the sponges, none of the methods accurately estimated the pore size. Conclusion For the simulated signals, Tufts-Kumaresan had the lowest performance, whereas SAC and MUSIC had similar results. For sponges, only Tufts-Kumaresan was able to detect the increase in the size of the pores of the sponge, although most often, it estimated sizes larger than expected.

Breast tumor classification in ultrasound images using support vector machines and neural networks

Abstract Introduction The use of tools for computer-aided diagnosis (CAD) has been proposed for detection and classification of breast cancer. Concerning breast cancer image diagnosing with ultrasound, some results found in literature show that morphological features perform better than texture features for lesions differentiation, and indicate that a reduced set of features performs better than a larger one. Methods This study evaluated the performance of support vector machines (SVM) with different kernels combinations, and neural networks with different stop criteria, for classifying breast cancer nodules. Twenty-two morphological features from the contour of 100 BUS images were used as input for classifiers and then a scalar feature selection technique with correlation was used to reduce the features dataset. Results The best results obtained for accuracy and area under ROC curve were 96.98% and 0.980, respectively, both with neural networks using the whole set of features. Conclusion The performance obtained with neural networks with the selected stop criterion was better than the ones obtained with SVM. Whilst using neural networks the results were better with all 22 features, SVM classifiers performed better with a reduced set of 6 features.

Phytochemical screening of the dichloromethane–ethanolic extract of Eriosema campestre var. macrophylum roots and its antiproliferative effect on human peripheral blood lymphocytes

ABSTRACT Eriosema campestre var. macrophylum (Grear) Fortunato, Fabaceae, is a native plant of the Brazilian Cerrado and the decoction of its roots has been used by folk medicine for the therapy of inflammatory diseases. In this study we aimed to investigate the effect of the dichloromethane–ethanolic extract of E. campestre roots on the proliferative response of lymphocytes and to examine the profile of IL-2 production. The effect of dichloromethane–ethanolic extract of E. campestre on the proliferation of phytohemagglutinin-stimulated lymphocytes was evaluated by using flow cytometry and the cell supernatants were assayed for IL-2 concentrations by using an enzyme-linked immunosorbent assay. The phytochemical screening of E. campestre roots was performed to determine the main secondary metabolites through chromogenic and precipitation reactions and by using HPLC-PAD. In addition to the presence of subclasses of flavonoids (flavones and flavonols) in dichloromethane–ethanolic extract of E. campestre, we observed that the extract induced a concentration-dependent decrease in IL-2 levels on the supernatant of the cell cultures as well as an antiproliferative effect on T lymphocytes, including CD4+ and CD8+ cells. The anti-inflammatory effects attributed to E. campestre by folk medicine may partly be explained by its antiproliferative action on T lymphocytes.

Effect of low-intensity therapeutic ultrasound on wound healing in rats subjected to third-degree burns

PURPOSE: To determine the effectiveness of low-intensity therapeutic ultrasound (LITUS) on wound healing in rats with third-degree burns. METHODS: Twenty rats were divided into the Control Group that comprised four rats without third-degree burns that did not undergo LITUS, the Burned Group (BG), comprising eight rats with third-degree burns that did not undergo LITUS, and the Burned with Treatment Group (BTG), comprising eight rats with third-degree burns that were administered LITUS. LITUS began 24 h after injury and involved daily applications for 8 min at 0.1 W/cm2 for 14 days. RESULTS: The BTG lost less weight than the BG (Q=2.75; p<0.05). No visible differences were apparent among the groups' lesions on day 4. By the end of treatment, wound healing was more evident in the BTG. No statistically significant differences were found between the BG and the BTG in relation to the parameters measured using the histological changes in burn wound healing scoring system. CONCLUSION: The LITUS protocol applied to the animals with third-degree burns accelerated the formation of fibrin-leukocyte crusts and significantly reduced weight loss. However, burn wound healing was not accelerated.

Diversidad de cetáceos en el paisaje marino costeros de Golfo Dulce, Península de Osa, Costa Rica / Diversity of cetaceans in coastal seascape Golfo Dulce, Osa Peninsula, Costa Rica

Resumen Golfo Dulce es un estuario en forma de fiordo, localizado en el Pacífico Sur de Costa Rica. Este ecosistema marino-costero contiene una importante biodiversidad marina que incluye cetáceos. Este estudio describe la estructura de la comunidad de cetáceos en Golfo Dulce, sustentado en la diversidad de hábitats. Datos sobre avistamientos colectados en muestreos periódicos sistemáticos, han resultado en 943 registros (2005-2014≈3 490h≈64 533km) de siete especies de la familia Delphinidae, una Balaenopteridae y una especie de la familia Kogiidae. Se observa un gradiente en la diversidad de cetáceos desde la cuenca interna de Golfo Dulce hasta la zona de transición- oceánica en la entrada al Golfo. La dominancia se establece por la forma costera del delfín nariz de botella y el delfín manchado en la cuenca interna, mientras que T. truncatus junto con ballenas jorobadas migrantes ejercen la dominancia en el área del Umbral. El área transicional oceánica sostiene la mayor diversidad, dominada por especies de delfínidos de naturaleza piscívora, incluyendo la forma oceánica del delfín nariz de botella y la subespecie "Centroamericana" del delfín tornillo. Nosotros proponemos la hipótesis de una forma potencial particular del delfín manchado pantropical para Golfo Dulce, en contraste con S. attenuatta graffmani en aguas abiertas costeras del Pacífico Costarricense. El patrón de la estructura comunitaria de cetáceos se establece por la dinámica en uso de área por las especies presentes, lo cual debería ser considerado para el diseño de estrategias de manejo y conservación.

Abstract Golfo Dulce is a fiord-lilke embayment located in the southern Pacific of Costa Rica, this coastal-marine ecosystem harbors an important wealth in marine biodiversity, including cetaceans. In this study we describe the cetacean community of Golfo Dulce, in relation to the diversity of habitats constituting the seascape. Sighting data collected in periodic systematic surveys has yielded 943 records (2005-2014≈3 490h≈64 533km), of 12 species of cetaceans. A gradient of cetacean diversity is observed from the inner basin to the transitional-oceanic area at the entrance of the Gulf, with coastal bottlenose dolphin and spotted dolphin dominating the inner basin, and bottlenose dolphins and migratory humpback whales the sill area. Transitional oceanic habitat holds the greatest species diversity dominated by oceanic species, particularly piscivorous delphinids, including the off-shore form of bottlenose dolphins and the "Central American" spinner dolphin. We hypothesize the potential occurrence of a morphotype of pantropical spotted dolphins within Golfo Dulce, in contrast with S. attenuatta graffmani outside in open Pacific coastal waters. The pattern of cetacean community structure is established by the dynamic of area use by the species, which should be considered for the establishment of management and conservation strategies. Rev. Biol. Trop. 63 (2): 395-406. Epub 2015 June 01.

Agregaciones de alimentación del tiburón ballena, Rhincodon typus (Orectolobiformes: Rhincodontidae) en Golfo Dulce, Península de Osa, Costa Rica / Whale shark, Rhincodon typus (Orectolobifoms: Rhincodontidae) feeding aggregations in Golfo Dulce, Osa Peninsula, Costa Rica

Resumen El tiburón ballena (Rhincodon typus), es el condrictio viviente más grande del mundo, con una distribución cosmopolita, encontrándose tanto en mares tropicales como subtropicales. La Unión Mundial para la Conservación (IUCN) lo clasifico como vulnerable y con una tendencia poblacional en disminución, conocido por realizar grandes agregaciones alrededor del mundo, relacionadas a procesos oceanográficos que incrementan la productividad primaria del ambiente marino. Por primera vez, se reporta cuatro eventos de alimentación de tiburón ballena dentro de la cuenca interna de Golfo Dulce, un fiordo tropical ubicado en la costa del Pacífico Sur de Costa Rica. Los avistamientos fueron realizados en enero y agosto del 2009, marzo 2012 y enero del 2013, donde la estructura y tamaño de los grupos se mantuvo constante en el tiempo encontrándose una proporción similar de adultos y juveniles. Estas agregaciones fueron observadas en la costa occidental de Golfo Dulce en un área que abarcaba los 23km, cerca de los ríos Rincón y Tigre, siendo estos los responsables de una alta concentración de nutrientes que favorecen la presencia de comunidades planctónicas. Durante las agregaciones se observó la presencia de zooplancton en la columna de agua, copépodos (Orden: Calanoidea). Dada la vulnerabilidad del tiburón ballena, es de suma importancia la implementación de estrategias de manejo de las actividades antropogénicas que se desarrollan en el Golfo, como son las actividades turísticas, desarrollo costero, aumento del tráfico marítimo, y la pesca comercial y deportiva, que ponen en riesgo a esta especie bandera.

Abstract The zooplanktivorous whale shark (Rhincodon typus), is the largest living chondrichthyan and a cosmopolitan species, living in tropical, warm and temperate waters. It is considered vulnerable by the International Union for Conservation of Nature (IUCN), and is known for big aggregations in many parts of the world. These are associated with particular oceanographic features where primary productivity is thought to be high. For the first time, four whale shark feeding aggregations are documented in Golfo Dulce, Costa Rica, a tropical fjord-like embayment located in the south Pacific region of the country. Observations were made in January and August 2009, March 2012 and in January 2013, Estimated group structure and size remained constant over time with an equal proportion of adults and juveniles in the same area. These aggregations were observed on the north-western coast of Golfo Dulce's inner basin, close to the Rincón and Tigre rivers. These two rivers are known to provide organic material which area important nutrients for the gulf zooplanktonic communities. During one of the observed feeding aggregations, copepods (Order: Calanoida) were seen in the water close to feeding individuals. Given the vulnerability of whale sharks, management decisions for Golfo Dulce need to include strategies to control tourism, boat circulation, commercial and sports fisheries and coastal development. Rev. Biol. Trop. 63 (Suppl. 1): 299-306. Epub 2015 April 01.

Efeitos da temperatura e regime de luz sobre Corynespora cassiicola e da temperatura e período de molhamento foliar no desenvolvimento da mancha-alvo em acerola / Effects of temperature and light regime on Corynespora cassiicola and of temperature and of leaf wetness period in development of target spot in barbados cherry

O presente estudo teve como objetivos: (i) determinar, in vitro, o efeito da temperatura sobre o crescimento micelial (10 a 35oC) e a germinação de conídios (10 a 45oC) de Corynespora cassiicola ; (ii) avaliar, in vitro , o efeito do regime de luz (luz contínua, fotoperíodo de 12 h e escuro) sobre o crescimento micelial, a esporulação e a viabilidade dos esporos de C. cassiicola ; e (iii) verificar, in vivo , a influência da temperatura (20 a 30oC) e da duração do período de molhamento foliar (4 a 48 h) no desenvolvimento da mancha-alvo em folhas de acerola. As temperaturas ótimas, estimadas a partir das equações, para o crescimento micelial e a germinação de esporos foram de 30 e 29oC, respectivamente. O regime de luz não afetou o crescimento micelial e a germinação dos esporos, entretanto, luz contínua favoreceu a esporulação, e a ausência de luz durante a produção dos esporos diminuiu sua viabilidade. Houve um incremento na área das lesões da mancha-alvo em folhas de acerola conforme a temperatura aumentou até 30oC. Foram necessárias 12 h de molhamento foliar para que a infecção e as lesões ocorressem.(AU)

The objective of this study were: (i) to assess, in vitro , the effect of temperature on mycelial growth (10-35oC) and spores germination (10-45oC); (ii) to evaluate, in vitro¸the effect of the light regime (continuous light, 12 h photoperiod and continuous darkness) on mycelial growth, sporulation and viability of the spores of C. cassiicola ;and (iii) to assess, in vivo,the effect of temperature (20-30oC) and the duration of leaf wetness (4-48 h) in the development of target spot in leaves of barbados cherry. The estimated maximum temperatures for mycelia growth and spore germination were 30 and 29oC, respectively. The light regime did not affect the mycelial growth and spores germination. However, continuous light regime favored the sporulation, and the absence of light during spore production decreased the spore viability. The target spot lesions area in barbados cherry leaves increased with the increment in the temperature up to 30oC. Twelve hours of leaf wetness were necessary for the infection and lesion development of target spot.(AU)

Análise estabilométrica após exercícios proprioceptivos: estudo clínico controlado randomizado / Analysis after stabilometric proprioceptive exercises: a randomized controlled clinical study

OBJETIVO: identificar as alterações estabilométricas antes e após um programa de treinamento proprioceptivoMÉTODO: um estudo clinico controlado randomizado foi realizado com 18 indivíduos, com idade média de 20,6 ± 2,1 anos de idade, de ambos os sexos, com índice de massa corporal médio de 23,3 ± 5,4 Kg/m2, que foram avaliados na plataforma estabilométrica antes e após um programa de treinamento proprioceptivo, utilizando os aparelhos balancim e disco proprioceptivo,e divididos em grupo propriocepção (n = 10) e grupo controle (n = 8). O treinamento proprioceptivo foi composto de 10 intervenções com apoio unipodal, em semiflexão de joelho, durante 30 segundos,duas vezes por semana, durante cinco semanas, utilizando os aparelhos balancim e disco proprioceptivoRESULTADOS: foram realizados testes de D'Agostino, para testar a normalidade, ao qual observou-se que a amostra estudada obteve comportamento normal para ambos os grupo: propriocepção e controle, de tal forma que utilizou-se o teste T-Studentpara observação da significância do valor de p (<0,05). Ao término das intervenções os indivíduos foram reavaliados na plataforma estabilométrica na qual observou-se que no grupo propriocepção houve uma redução significativa da oscilação corporalem relação ao grupo controle (p = 0,002CONCLUSÃO: a curto prazo o treinamento proprioceptivo unipodal demonstrou-se eficaz para a melhora do equilíbrio com a redução das oscilações corporais.

OBJECTIVE: identify stabilometric changes before and after a program of proprioceptive training METHODS: a randomized controlled clinical trial was conducted with 18 subjects, mean age 20.6 ± 2.1 years of age, of both sexes, with a mean body mass index 23.3 ± 5.4 kg/m² that were evaluated in stabilometric platform before and after a program of proprioceptive training using the equipment and proprioceptive hard rocker, and divided into proprioception (n = 10) and control group (n = 8) group. The proprioceptive training consisted of 10 measures with one foot, knee in semiflexion for 30 seconds twice a week for five weeks using the rocker apparatus and proprioceptive disc RESULTS: D'Agostinotests were performed to test the normality, to which it was noted that the study sample was obtained normal behavior for both groups: proprioception and control, was used the Student t-test for observation the significance of p value (<0.05). At the end of the intervention subjects were reassessed at stabilometric platform on which it was observed that the proprioception group there was a significant reduction in body sway in relation to the control group (p = 0.002) CONCLUSION: the short time, with one leg proprioceptive training has been shown to be effective for improving balance by reducing body sway.

Continuous flow phantom for the calibration of an ultrasonic transit-time flowmeter

INTRODUCTION: Ultrasound Transit-Time flowmeters are based on the fact that the time required for an ultrasound pulse to propagate through a given distance in a moving medium is a function of the vectorial sum of pulse propagation velocity and medium velocity. The most common application of this flowmeter in medicine is in the evaluation of blood flow in arteries and veins during heart vascular surgery. The present article describes the design, construction and evaluation of a flow phantom for transit-time flowmeters calibration. METHODS: Basically, it is a hydraulic circuit containing degassed and distilled water. In such a circuit, a constant differential water level is established between two columns that are interconnected by tubes with defined resistance, which determines a known flow rate. A basic theoretical model to estimate the system Reynolds Number and resistance was developed. RESULTS: A flow range between 4.43 ± 0.18 ml.min-1 and 106.88 ± 0.27 ml.min-1 was found to be compatible with physiological values in small vessels. The pressure range was between 0.20 ± 0.03 cmH2O and 12.53 ± 0.07 cmH2O, and the larger Reynolds Number was 1134.07. Experimental and theoretical resistance values were similar. CONCLUSION: A reproducible phantom was designed and built to be assembled with standard low-cost materials and is capable of generating adjustable and continuous flows that can be used to calibrate TTFM systems.

Segmenting mammographic microcalcifications using a semi-automatic procedure based on Otsu's method and morphological filters

INTRODUCTION: Breast cancer has the second highest world's incidence rate, according to the Brazilian National Cancer Institute (INCa). Clinical examination and mammography are the best methods for early diagnosis. Computer-aided detection (CADe) and computer-aided diagnosis (CADx) systems are developed to improve mammographic diagnosis. Basically, CADx systems have three components: (i) segmentation, (ii) parameters extraction and selection, (iii) lesion classification. The first step for a CADx system is segmentation. METHODS: A microcalcification segmentation method is proposed, based on morphological operators, Otsu's Method and radiologists' knowledge. Pre-processing with top-hat operators improves contrast and reduces background noise. The Otsu's method automatically selects the best grey-level threshold to segment microcalcifications, obtaining binary images. Following, inferior reconstruction and morphological dilatation operators are applied to reconstruct lost structure details and fill small flaws in the segmented microcalcifications. Finally, the Canny edge detection is applied to identify microcalcifications contour candidates for each region-of-interest (ROI). Two experienced radiologists intervene in this semi-automatic method, firstly, selecting the ROI and, then, analyzing the segmentation result. The method was assessed in 1000 ROIs from 158 digital images (300 dpi, 8 bits). RESULTS: Considering the radiologists opinion, the rates of ROIs adequately segmented to establish a diagnosis hypothesis were 97.8% for one radiologist and 97.3% for the other. Using the Area Overlap Measure (AOM) and the 2136 microcalcifications delineated by an experienced radiologist as gold standards, the method achieved an average AOM of 0.64±0.14, being 0.56±0.09 for small microcalcifications and 0.66±0.13 for the large ones. Moreover, AOM was 0.64±0.13 for the benign and 0.64±0.14 for the malignant lesions with no statistical differences between them. CONCLUSION: Based on these findings, the proposed method could be used to develop a CADx system that could help early breast cancer detection.

Calorímetro diferencial para estudo do padrão de aquecimento gerado por feixes ultrassônicos terapêuticos / Differential calorimeter for studying the heating pattern generated by therapeutic ultrasonic beams

O presente trabalho descreve o projeto e construção de um calorímetro diferencial com a finalidade de avaliar o aquecimento gerado por feixes ultrassônicos em níveis terapêuticos. O calorímetro consiste em duas câmaras cilíndricas de alumínio idênticas (de medição e de referência), preenchidas com um material mimetizador de tecido biológico (phantom). Cada câmara possui seis termopares tipo E (diâmetro 0,24 mm), posicionados ao longo do eixo central de propagação da onda, entre as profundidades 10-60 mm, distantes 10 mm entre si. Foi levantada a curva de potência e estimado o valor da área de radiação efetiva (ERA) dos dois transdutores utilizados. A partir destes dados, a intensidade efetiva foi determinada. Para avaliar o calorímetro, foi utilizado um equipamento de ultrassom de Fisioterapia, operando nas frequências nominais 1 e 3 MHz, modo contínuo, intensidades nominais 0,5; 1,0; 1,5 e 2,0 W.cm-2 e tempo de irradiação 180 segundos. Uma sequência de oito protocolos de medição foi realizada dez vezes. Para ambas as frequências, houve um declínio do aquecimento ao longo da profundidade e a região do "phantom" que mais aqueceu foi a que corresponde à profundidade de 10 mm, em todas as intensidades. O maior aquecimento ocorreu a 2,0 W.cm-2, com médias de 6,7 ± 1,0 ºC e 12,6 ± 1,2 ºC, a 1 MHz e 3 MHz, respectivamente. O calorímetro proposto mostrou-se útil na caracterização de feixes ultrassônicos aplicados em Fisioterapia, principalmente na identificação de possíveis máximos locais de temperatura (pontos quentes) que ocorrem ao longo do eixo principal do feixe.

The present work describes the project and construction of a differential calorimeter designed to evaluate the heating generated by ultrasound beam in therapeutic levels. The calorimeter consists of two identical aluminum cylindrical chambers (for measurement and reference) filled with biological tissue mimicking material (phantom). Each chamber is fitted with six thermocouples type E (0.24 mm diameter) disposed along the wave propagation central axis, between the depths of 10-60 mm, distant 10 mm from each other. The power curve and the value of the effective radiation area (ERA) of the two transducers were estimated. From these data, the effective intensity was determined. The calorimeter was tested by using an ultrasound equipment of Physiotherapy, operating at the frequencies 1 and 3 MHz, continuous mode, nominal intensities 0.5, 1.0, 1.5 and 2.0 W.cm-2 and irradiation time 180 seconds. A sequence of eight protocols of measurement was repeated 10 times. At both frequencies, there was a decline of heating along the depth and the phantom region that heated the most corresponded to 10 mm of depth, in all intensities employed. The greatest increase in temperature occurred after application of 2.0 W.cm-2, with averages of 6.7 ± 1.0 ºC and 12.6 ± 1.2 ºC, at 1 MHz and 3 MHz, respectively. The proposed calorimeter may be useful for identifying possible local temperature maxima (hot spots) that appear along the central axis beam.

Detecção automática do espaçamento médio de meios periódicos por sinais ultrassônicos retroespalhados / Automatic detection algorithms for mean scatterer space estimation using ultrasound backscattered signals

A interpretação da imagem ultrassônica, por ocorrer de modo visual e qualitativa, traz uma variação inter e intra-observador importante. A adoção de métodos quantitativos é uma forma de diminuir esta dependência. Entre tais métodos está a quantificação do espaçamento médio entre espalhadores (Mean Scatterer Spacing - MSS), que pode ser útil para detectar mudanças na microestrutura quasi-periódica de tecidos como o hepático ou o esplênico. Neste trabalho foram avaliados três métodos clássicos de estimação espectral para cálculo do MSS (sem intervenção do operador): BURG, WIENER e MUSIC. O intuito é comparar suas potencialidades para a estimação automática de espaçamento médio de espalhadores ultrassônicos. Inicialmente as avaliações foram realizadas com 10.000 sinais simulados a partir de um modelo em que se tem controle das variáveis de interesse, e em seguida foram utilizados sinais reais de phantoms de fios de nylon imersos em água. O método de BURG não conseguiu estimar adequadamente o espaçamento em sinais de phantom, tendo apresentado resultados equivalentes aos outros métodos deste trabalho somente para sinais simulados. O método de WIENER para os sinais simulados apresentou resultados de menor percentual de acerto, ficando em segundo lugar, para os sinais dos phantoms. O método de subespaço MUSIC apresentou melhor desempenho global em relação a BURG e WIENER, com resultados de 100% de acerto para o phantom de fio de nylon de 1,2 mm e 91,45% para 0,8 mm considerando uma janela de acerto de 10%.

The interpretation of ultrasound imaging is essentially visual and qualitative, so there are important inter and intra-observer variations. Quantification methods aim at decreasing this dependency. Among those, the quantification of the Mean Scatterer Spacing (MSS) can be useful to detect changes in the microstructure of quasi-periodic tissues, such as liver or spleen. This study evaluated the following methods of spectral estimation for calculating the MSS (without requiring operator intervention): BURG, WIENER and MUSIC. The aim is to compare their potential for automatic estimation of MSS from ultrasonic scattering signals. Initially, the evaluation has been carried out using 10,000 simulated signals, with the aim of studying the behavior of the methods using a model in which the variables of interest can be controlled. Then, the methods have been applied to real signals of nylon phantoms immersed in water. The BURG method could not estimate the spacing of US phantom signals, presenting results similar to the other methods only for simulated signals. The WIENER method for the simulated signals was in second place in terms of percentage of success, when considering signals from the phantoms. The subspace method MUSIC had the best performance from all three methods.

CAD e mamografia: por que usar esta ferramenta? / CAD and mammography: why use this tool?

A mamografia representa o melhor método de detecção precoce do câncer de mama, porém cerca de 10 por cento a 30 por cento das lesões mamárias são perdidas no rastreamento, devido a limitações próprias dos observadores humanos. A detecção auxiliada por computador (computer-aided detection - CAD) é uma tecnologia relativamente nova que tem sido implementada em alguns serviços de mamografia, com o intuito de prover uma dupla leitura. Estudos clínicos têm demonstrado que o CAD aumenta a sensibilidade de detecção do câncer da mama, por radiologistas, em até 21 por cento. Um sistema CAD é útil em situações em que exista alta variabilidade interobservador, falta de observadores treinados, ou na impossibilidade de se realizar a dupla leitura com dois ou mais radiologistas. O objetivo desta revisão está baseado na necessidade de atualizar a comunidade médica acerca desta ferramenta, como um método auxiliar, quantitativo, não operador-dependente, e que visa a melhorar a qualidade do diagnóstico do câncer de mama.

Mammography is the best method for early detection of breast cancer. Nevertheless, approximately 10 percent to 30 percent of breast lesions are missed at screening due to limitations of human observers. Computer-aided detection (CAD) is a relatively new technology that has been implemented in some mammography services to allow a double reading of mammograms. Clinical studies have demonstrated that CAD increases the sensitivity by up to 21 percent in the detection of breast cancer by radiologists. A CAD system is useful in situations where there is a high interobserver variability, lack of trained observers, or impossibility to perform the double reading with two or more radiologists. The objective of the present review is based on the need to get the medical community acquainted with this tool as an auxiliary, quantitative and non-operator-dependent method, to improve the diagnosis of breast cancer.