Efeitos do exercício resistido sobre o tecido adiposo marrom em camundongos C57BL/6 / Effects of resisted exercise on brown adipous tissue in C57BL/6 mice

OBJETIVO: Verificar os efeitos do treinamento de escada e atividade física na histomorfometria do tecido adiposo marrom em camundongos C57BL/6. MATERIAIS E MÉTODOS: Amostra composta por 16 camundongos, divididos aleatoriamente: controle (n=4), exercício de escada com estímulo elétrico (n=4), exercício de escada (n=4) e atividade física em ambiente enriquecido (n=4). Grupo de atividade física em ambiente enriquecido foi realizada em caixa com brinquedos. Grupo exercício de escada e escada com estímulo elétrico foram realizadas com escada vertical. Com a utilização da escada os animais realizaram 6 séries, 8 repetições com intervalos de 90 segundos entre séries, sendo 10 sessões. No exercício de escada com estimulo elétrico, o animal foi estimulado a subir usando uma placa de aço na base da escada, com uma corrente elétrica de 20V de intensidade e 45 hz de frequência. A coleta de tecido adiposo marrom foi feita na região escapular e manchado em Hematoxilina-Eosina (HE). O nível de significância das análises era 95% (p < 0.05). RESULTADOS: Não houve diferença significativa no comparativo do tamanho da célula de TAM em comparação com o tecido recolhido dos camundongos dos quatro grupos. CONCLUSÃO: A atividade física e o exercício resistido não promoveram diferenças morfometricas no TAM dos camundongos C57BL/6.

OBJECTIVE: To verify the effects of stair training and physical activity on brown adipose tissue histomorphometry in C57BL / 6 mice. MATERIALS AND METHODS: Sample composed of 16 mice, randomly divided: control (n = 4), stair exercise with electrical stimulus (n = 4), stair exercise (n = 4) and physical activity in an enriched environment (n = 4). A Group of physical activity in an enriched environment was performed in a box with toys. Ladder exercise group and ladder with electrical stimulus were performed with vertical ladder. With the ladder's use, the animals performed six sets, eight repetitions with 90-second intervals between sets, with ten sessions. In the stairway exercise with electrical stimulation, the animal was encouraged to climb using a steel plate at the base of the stairs, with an electric current of 20V intensity and 45Hz frequency. Brown adipose tissue collection was performed in the scapular region and stained with Hematoxylin-Eosin (HE). The level of significance of the analyzes was 95% (p <0.05). RESULTS: There was no significant difference when comparing the TAM cell size compared to the tissue collected from the mice in the four groups. CONCLUSION: Physical activity and resistance exercise did not promote morphometric differences in the TAM of C57BL/6 mice.

The advantage of topographic prominence-adopted filter for the detection of short-latency spikes of retinal ganglion cells

Electrical stimulation through retinal prosthesis elicits both short and long-latency retinal ganglion cell (RGC) spikes. Because the short-latency RGC spike is usually obscured by electrical stimulus artifact, it is very important to isolate spike from stimulus artifact. Previously, we showed that topographic prominence (TP) discriminator based algorithm is valid and useful for artifact subtraction. In this study, we compared the performance of forward backward (FB) filter only vs. TP-adopted FB filter for artifact subtraction. From the extracted retinae of rd1 mice, we recorded RGC spikes with 8×8 multielectrode array (MEA). The recorded signals were classified into four groups by distances between the stimulation and recording electrodes on MEA (200-400, 400-600, 600-800, 800-1000 µm). Fifty cathodic phase-1(st) biphasic current pulses (duration 500 µs, intensity 5, 10, 20, 30, 40, 50, 60 µA) were applied at every 1 sec. We compared false positive error and false negative error in FB filter and TP-adopted FB filter. By implementing TP-adopted FB filter, short-latency spike can be detected better regarding sensitivity and specificity for detecting spikes regardless of the strength of stimulus and the distance between stimulus and recording electrodes.

Correlation between electrical stimulus intensity and postoperative complications of puncture trigeminal ganglion radiofrequency thermocoagulation / 实用医学杂志

Objective To investigate the relationship between electrical stimulus intensity and postopera-tive complications of puncture trigeminal ganglion radiofrequency thermocoagulation (PTGRT). Methods 86 pa-tients with trigeminal neuralgia (TN) on the second and the third branch underwent trigeminal ganglion radiofre-quency thermocoagulation in Xuanwu Hospital , Capital Medical University from June 2013 to December 2015 enrolled in this study. Electrical stimulus intensity in surgery and postoperative pain VAS score , numbness score, masseter muscles score and complications were recorded at 0, 24 and 48 hours post-surgery. Correlations among electrical stimulus intensity in surgery and postoperative pain VAS score,numbness score, masseter mus-cles score were analyzed. Result The 86 patients had different degrees of facial numbness , some patients had different degrees of masseter weakness , and 2 patients had mild sialorrhea in two days after PTGRT without serve complications. Eighty-three patients (96.51%) had no pain, and VAS score wass 0 at 0, 24 and 48 hours post-PTGRT. Electrical stimulus intensity in surgery had apparent negative correlation with numbness score at 0 , 24 and 48 hours popst-PTGRT (P < 0.01), with negative correlation with masseter muscles decreasing at 48 hours post-PTGRT (P < 0.05). Conclusion Suitable temperature and time in PTGRT were needed to be chose ac-cording to the electrical stimulus intensity.

Electrical stimulation in the bone repair of defects created in rabbit skulls / Estimulación eléctrica en la reparación ósea de defectos creados en cráneos de conejos

Electrical stimulation has been used in different conditions for tissue regeneration. The aim of this study was to analyze the tissue response of defects created in rabbit skulls to electrical stimulation. Two groups were formed, each with 9 New Zealand rabbits; two 5 mm defects were made, one in each parietal, with one being randomly filled with autogenous bone extracted as particles and the other maintained only with blood clotting. The rabbits were euthanized at 8 weeks and 15 weeks to then study the samples collected histologically. In the 8-week analysis bone formation was observed in the defects in the test and control filled with bone graft, whereas the defects with clotting presented a very early stage of bone formation with abundant connective tissue. At 15 weeks an advanced stage of bone regeneration was identified in the defects with bone graft, whereas no significant differences were found in the electrically stimulated defects. In conclusion, electrical stimulus does not alter the sequence of bone formation; new studies could help establish patterns and influences of the stimulus on bone regeneration.

La estimulación eléctrica ha sido empleada en diferentes condiciones para la regeneración de tejidos. El objetivo de esta investigación es analizar la respuesta tisular de defectos creados en cráneo de conejos a la estimulación eléctrica. Se formaron 2 grupos con 9 conejos de raza New Zealand cada uno; en ellos se realizaron dos defectos de 5 mm, uno en cada parietal, siendo aleatoriamente uno rellenado con el propio hueso autógeno extraído en forma de partículas y el otro mantenido solo con coagulo sanguíneo; se realizó la eutanasia a las 8 semanas y a las 15 semanas para luego estudiar histológicamente las muestras recolectadas. En el análisis de 8 semanas se observó formación ósea en los defectos test y control rellenados con injerto óseo mientras que los defectos con coagulo presentaron un estado muy precoz de formación ósea, observándose abundante tejido conectivo. A las 15 semanas se identificó un estado avanzado de regeneración ósea en los defectos con injerto óseo, donde no se apreció diferencias importantes en los defectos estimulados eléctricamente. Se concluye que el estimulo eléctrico no altera la secuencia de formación ósea; nuevos estudios podrían contribuir a establecer patrones e influencias del estimulo eléctrico en la regeneración ósea.

Effects of Electrical Stimulus on Bone Properties in Rats with Sciatic Denervation / The Japanese Journal of Rehabilitation Medicine

This study investigated the effects of electrical stimulus on bone properties in rats with sciatic denervation. Forty-eight Wistar rats aged 8 week-old were used and divided into 4 groups, randomly. One group was sham-operated (SHAM) as a control, and the sciatic nerves of the lateral hind limbs were cut in the remaining 3 groups (DN). Two groups of DN rats received electrical stimulus at both hind limbs to induce planter flexion for 15 min, 2 sets/day, 5 days/week, at 15 or 60 Hz. The rats in each group were sacrificed at 1, 2, 3 and 4 weeks after the operation. All tibias were measured by three-pointed bending test, and bone mechanical strength was calculated. Also, the dry bone weight and ash content of the bones were measured. A reduction of all bone properties in DN was shown from a week after operation onwards and that in DN+15 Hz from two weeks after operation onwards. Bone properties in DN+60 Hz were decreased in order of maximum load, ash content, mechanical strength, and dry bone weight from two weeks after operation onwards. These results suggest that electrical stimulus can delay the progression of bone atrophy, and that high frequency stimulation (60 Hz) is more effective than low frequency stimulation (15 Hz) in this regard.

Effect of electrical stimulus at a low physiological frequency on expression of myosin heavy chain in genioglossus of rabbits with chronic hypoxia / 第三军医大学学报

Objective To study the effect of chronic electrical stimulus at a low physiological frequency on the expression of myosin heavy chain (MHC) in genioglossus of rabbits with chronic hypoxia.Methods Twenty-four adult rabbits,weighing 2.3?0.1kg,were randomized into control group (A),chronic hypoxia group (B),10 Hz electrical stimulus group (C),and 10+40 Hz electrical stimulus group (D).Rabbits in groups C and D received electrical stimulus of genioglossus at a frequency of 10 Hz and 10+40 Hz,respectively,while those in group B received no electrical stimulus,after they were placed in a hypobaric hypoxia cabin,8 h a day for 5 weeks,with free access to food and water.Expression of MHC in genioglossus of rabbits in the 4 groups was detected by SDS-PAGE and semi-quantitative inverse transcription RT-PCR,respectively.Results The expression level of MHCⅠand MHCⅠmRNA was significantly lower while that of MHCⅡa was significantly higher in group B than in group A [(0.69?0.07)% vs (17.48?4.00)%,(0.69?0.07)% vs (1.05?0.06)%,and (79.89?5.09)% vs (73.33?4.17)%,P