Measurement of healing area using planimetry after applying low-intensity ultrasound to the skin of rats

CONTEXTUALIZAÇÃO: A planimetria é um método utilizado para avaliar a evolução da cicatrização de feridas. A planimetria computacional é um método ainda em experimentação, mas cujas vantagens têm sido demonstradas em várias investigações. OBJETIVOS: Avaliar os efeitos do ultra-som pulsado de baixa intensidade sobre a cicatrização de lesão cutânea produzida na região dorsal de ratos, por meio da planimetria computacional. MATERIAIS E MÉTODOS: Utilizou-se 60 ratos machos Wistar (peso médio de 300g) divididos em dois grupos com 30 animais cada, de acordo com o tratamento: 1) irradiação simulada (controle); 2) irradiação efetiva (Freqüência fundamental de 1,5MHz, freqüência de repetição de pulsos de 1KHz, largura de pulso de 200µs, intensidade de 30mW/cm² SATA, dez minutos de aplicação em dias alternados). Cada grupo foi subdividido em três grupos, de acordo com o período de irradiação ultra-sônica, de três, sete e 14 dias, respectivamente, e a cicatrização foi avaliada por meio da planimetria, um decalque da lesão sendo obtido em papel especial, digitalizado e medido ao computador por meio de um programa gráfico. Análise estatística pelo método não-paramétrico de Mann-Whitney. RESULTADOS: Houve aumento significante (p<0,05) da área cicatrizada no grupo 2 (141,88±18,50mm²) em relação ao grupo 1 (117,38±15,14mm²), no 14º dia. Não houve diferenças significantes entre os grupos nos demais períodos. CONCLUSÕES: O ultra-som pulsado de baixa intensidade estimula a cicatrização cutânea por segunda intenção em condições experimentais. A planimetria computacional mostrou-se um recurso de baixo custo, fácil manuseio e de aplicabilidade clínica.BACKGROUND: Planimetry is a method used to evaluate the progression of skin wound healing. Computerized planimetry is still an experimental method, but its advantages have been demonstrated in several investigations. OBJECTIVE: To evaluate the effects of low-intensity pulsed ultrasound on the healing of a skin lesion produced on the dorsal region of rats, by means of computerized planimetry. METHODS: Sixty male Wistar rats of mean weight 300g were used. They were divided into two groups according to the treatment applied: 1) simulated irradiation (control); 2) effective irradiation (fundamental frequency 1.5MHz, pulse repetition frequency 1KHz, pulse width 200µs, SATA intensity 30mW/cm² and application for ten minutes on alternate days). Each group was divided into three subgroups according to the length of time for which ultrasound irradiation was applied of three, seven and 14 days, respectively, and healing was evaluated by means of planimetry; a tracing of the wound was obtained on special paper and this was digitized and measured by means of a graphing software. Statistical analysis was performed using the Mann-Whitney non-parametric method. RESULTS: The healed area was significantly greater (p<0.05) in group 2 (141.88±18.50mm²) than in group 1 (117.38±15.14mm²) on the 14th day. There were no significant differences between the subgroups for the other experimental periods. CONCLUSIONS: Low-intensity pulsed ultrasound irradiation stimulated secondary skin healing under these experimental conditions. Computerized planimetry was shown to be a low cost method that was easy to use and present clinical applicability

On the temperature behavior of shunt-leakage currents in Cu(In,Ga)Se2 solar cells: The role of grain boundaries and rear Schottky contact

By comparing simulated and measured dark current-voltage (I-V) characteristics of CIGS cells at different temperatures, we investigate the temperature behavior of the shunt leakage current, and find that it can be explained by large donor trap concentrations at grain boundaries (GBs), and by a Schottky barrier at the backside contact where the GBs meets the anode metallization. We studied the I-V characteristics in the temperature range 280 K - 160 K achieving good fits of the measured I-V curves, especially for reverse bias and low forward bias, where the shunt leakage current dominates. The most important parameters determining the shunt leakage current value and its temperature dependence are the peak energy and density of the GB donor distribution, which control the inversion of GBs and the pinning of Fermi level at the anode/GB contact

Transmission Electron Microscopy, High Resolution X-Ray Diffraction and Rutherford Backscattering Study of Strain Release in InGaAs/GaAs Buffer Layers

Strain release and dislocation distribution in InGaAs/GaAs double heterostructures, step-graded and linear-graded buffer layers have been studied. A higher misfit dislocation density at the inner interface between the InGaAs layer and the substrate was found in all the samples. This corresponded to a strain release of the inner ternary layers much larger than predicted by equilibrium theories. The residual parallel strain of the external layers as a function of their thickness was found to follow a curve approximately of slope -0.5, in agreement with previous investigations on single InGaAs layers. This result has been interpreted as evidence that the elastic energy per unit interface area remains constant during the epilayer growth. The presence of numerous single and multiple dislocation loops inside the substrate was attributed to the strain relaxation occurring through dislocation multiplication via Frank-Read sources activated during the growth. A comparison with InGaAs/GaAs step-graded and linear-graded heterostructures is also shown and briefly discussed. Finally, lattice plane tilts between epilayers and substrates have been found due to the imbalance in the linear density of misfit dislocations with opposite component of the Burgers vector, b⊥eff, perpendicular to the interface

Nestin-GFP Transgene Reveals Neural Precursor Cells in Adult Skeletal Muscle

Background: Therapy for neural lesions or degenerative diseases relies mainly on finding transplantable active precursor cells. Identifying them in peripheral tissues accessible for biopsy, outside the central nervous system, would circumvent the serious immunological and ethical concerns impeding cell therapy. Methodology/Principal Findings: In this study, we isolated neural progenitor cells in cultured adult skeletal muscle from transgenic mice in which nestin regulatory elements control GFP expression. These cells also expressed the early neural marker Tuj1 and light and heavy neurofilament but not S100b, indicating that they express typical neural but not Schwann cell markers. GFP+/Tuj1+ cells were also negative for the endothelial and pericyte markers CD31 and a-smooth muscle actin, respectively. We established their a) functional response to glutamate in patch-clamp recordings; b) interstitial mesenchymal origin; c) replicative capacity; and d) the environment necessary for their survival after fluorescenceactivated cell sorting. Conclusions/Significance: We propose that the decline in nestin-GFP expression in muscle progenitor cells and its persistence in neural precursor cells in muscle cultures provide an invaluable tool for isolating a population of predifferentiated neural cells with therapeutic potential

A influência da mobilização articular nas tendinopatias dos músculos bíceps braquial e supra-espinal The influence of joint mobilization on tendinopathy of the biceps brachii and supraspinatus muscles

As causas mais comuns de dor no ombro estão relacionadas às degenerações dos tendões da musculatura do manguito rotador. OBJETIVO: Verificar a influência da mobilização articular por meio dos movimentos acessórios do ombro na recuperação inicial de 14 pacientes com tendinopatia crônica dos mm. supra-espinal e/ou bíceps braquial. MÉTODOS: Foram comparados dois protocolos de tratamento, compostos da aplicação de ultra-som terapêutico na área do tendão afetado e de treinamento excêntrico na musculatura envolvida, acompanhados ou não de manobras de mobilização articular. Como métodos de avaliação foram utilizados os questionários de Constant e Disabilities of the Arm, Shoulder and Hand (DASH), no início e ao final do tratamento. RESULTADOS: Os resultados encontrados demonstraram que ambos os protocolos de tratamento foram eficazes na reabilitação dos pacientes, pois se obtiveram melhores resultados funcionais na aplicação dos questionários quando comparados o final com o início do tratamento para os pacientes (p<0,001). Os pacientes que foram submetidos à mobilização articular associada ao ultra-som terapêutico e o treinamento excêntrico obtiveram em média melhores escores para os questionários, ocorrendo diferença estatística significante entre os escores finais nos dois grupos para os dois questionários (p<0,05). CONCLUSÕES: Assim ambos os protocolos de tratamento foram eficazes no tratamento da tendinopatia crônica do ombro, sendo que, o uso associado da mobilização articular parece oferecer melhores resultados funcionais.<br>The most common causes of shoulder pain are related to degeneration of the tendons of the rotator cuff muscles. OBJECTIVE: To investigate the influence of joint mobilization by means of accessory movements of the shoulder during the early rehabilitation of 14 patients with chronic tendinopathy of the supraspinatus and/or biceps brachii muscles. METHODS: Two treatment protocols were compared: application of therapeutic ultrasound over the affected tendon area and eccentric training of the musculature involved, with or without joint mobilization maneuvers. The Constant and DASH (Disabilities of the Arm, Shoulder and Hand) questionnaires were used as the assessment method, before and after the treatment. RESULTS: The results showed that both treatment protocols were effective for patient rehabilitation, since better functional results were obtained at the end of the treatment, in comparison with the beginning (p<0.001). The patients who underwent joint mobilization in association with therapeutic ultrasound and eccentric training achieved better mean scores in the questionnaires. There was a statistically significant difference in the final scores between the two groups, for both questionnaires (p<0.05). CONCLUSIONS: Thus, both treatment protocols were effective for treating chronic tendinopathy of the shoulder, although their use in association with joint mobilization seems to provide better functional results