Striated Musculature: Embryonic and Fetal Development

SUMMARY: The different embryological origins of striated muscle tissue make it an interesting tissue but at the same time difficult to understand, this is how the musculature of the face comes from the first pharyngeal arch, on the other hand. The muscles of the tongue derive from the somites. The muscles of the larynx come from the pharyngeal arches. The muscles of the spine come from the medial or internal myotome of the somite, while the muscles of the limbs and body wall come from the external myotome. The cardiac musculature originates from the lateral splanchnic mesoderm. In this work, the development of myoblasts in human, mouse and chicken fetuses was studied in the facial region, tongue, and spine, limbs, body wall and cardiac muscles using histological histochemical techniques and immunohistochemical technique. The objective of the work is to compare the histogenesis of striated muscle (skeletal, visceral and cardiac), indicating the differences in origin, evolution of the morphological characteristics in each of them and the signaling routes that are involved in its development.

Los distintos origenes embriológicos del tejido muscular estriado lo hace un tejido interesante, pero a la vez difícil de entender, es así como la musculatura de la cara proviene del primer arco faríngeo, en cambio, la musculatura de la lengua deriva de los somitos. La musculatura de la laringe proviene de los arcos faríngeos. La musculatura de la columna vertebral proviene del miotomo medial o interno del somito, en cambio la musculatura de los miembros y pared del cuerpo proviene del miotomo externo. La musculatura cardiaca se origina del mesoderma lateral esplácnico. En este trabajo se estudió el desarrollo de mioblastos en fetos humanos, de ratón y pollo, en la región facial, lengua, columna vertebral, miembros, pared del cuerpo y musculatura cardíaca mediante técnicas histológicas histoquímicas y técnica inmunohistoquímica. El objetivo del trabajo fue comparar la histogénesis del músculo estriado (esquelético, visceral y cardíaco), indicando las diferencias de origen, evolución de las características morfológicas en cada una de ellas y las rutas de señalización que se ven involucradas en el desarrollo del mismo.

Vida e trabalho de refugiado: a imagem como experiência do olhar a partir de uma obra de Escher / Refugee's life and work: image as experience of the look from a painting by Escher

Vida e trabalho no percurso de refugiado estão entre os mais recentes desafios contemporâneos que instigam o olhar e o pesquisar. A fim de potencializar a discussão, julgou-se pertinente atentar para a experiência do olhar frente à imagem. Tomou-se a xilogravura Dia e Noite, arte de Maurits Cornelius Escher, que alude ao movimento migratório de pássaros, por também ela provocar o olhar dadas as características que o artista lhe imprime. Como base teórica condutora da discussão, tomaram-se os conceitos de espaço liso e estriado, de Deleuze e Guattari, imbricados em referencial relativo à situação de refugiado. A conversa entre imagem e teoria ampliou o olhar para além das questões burocráticas, jurídicas e estatísticas, frequentemente associadas aos estudos acerca de refugiado, e permitiu apontar relações de continuidade e coexistência em seus modos de viver e trabalhar. Entende-se que, ao provocar a experiência do olhar, a imagem pode ser capturada, recortada, reduzida, ampliada, torcida, num esforço de sentido não necessariamente óbvio.(AU)

Life and work on the refugee journey are among the latest contemporary challenges that instigate to look and to research. In order to enhance the discussion, it was considered pertinent to pay attention to the experience of looking at the image. We took the woodcut Day and Night, art by Maurits Cornelius Escher, which alludes to the migratory movement of birds, because it also provokes the look, given the characteristics that the artist imprints on it. The concepts of smooth and striated space, by Deleuze and Guattari, imbricated in a reference regarding the refugee situation, were taken as the theoretical basis for the discussion. The conversation between image and theory broadened the look beyond bureaucratic, legal and statistical issues, often associated with studies about refugees and allowed pointing out relationships of continuity and coexistence in their ways of living and working. It is understood that, by provoking the experience of the look, the image can be captured, cut, reduced, enlarged, twisted, in an effort of meaning not necessarily obvious.(AU)

La vida y el trabajo en el curso de la vida de los refugiados son algunos de los retos contemporáneos más recientes que instigan la mirada y la investigación. Para mejorar el debate, se consideró pertinente centrarse en la experiencia de mirar la imagen. Se tomó la xilografía Día y Noche, obra de Maurits Cornelius Escher, que alude al movimiento migratorio de las aves, ya que también provoca la mirada dadas las características que el artista le imprime. Los conceptos de espacio liso y estriado, de Deleuze y Guattari, se utilizaron como base teórica para la discusión. La conversación entre la imagen y la teoría amplió la mirada más allá de las cuestiones burocráticas, legales y estadísticas que suelen asociarse a los estudios sobre los refugiados, y nos permitió señalar relaciones de continuidad y convivencia en sus formas de vivir y trabajar. Se entiende que al provocar la experiencia de la mirada, la imagen puede ser capturada, recortada, reducida, ampliada, retorcida, en un esfuerzo por dar un sentido que no es necesariamente obvio.(AU)

Hallazgos microscópicos del tejido pulmonar y los músculos respiratorios en la Enfermedad Pulmonar Obstructiva Crónica (EPOC) / Microscopic Findings Of Lung Tissue And Respiratory Muscles In Chronic Obstructive Pulmonary Disease (COPD)

Introducción: En la enfermedad pulmonar obstructiva crónica (EPOC), el diafragma y los músculos respiratorios esternocleidomastoideos (ECOM) funcionan contra el aumento de las cargas mecánicas debido a la limitación del flujo de aire y los cambios en la conformación del tórax debido a la condición de hiperinflación pulmonar. Objetivo: Evaluar los cambios histopatológicos presentes en los pulmones y los músculos respiratorios (diafragma y ECOM) de los cadáveres con Diagnostico de EPOC. El Estudio: Este es un estudio ciego y descriptivo con análisis de imágenes histológicas de biopsia. El historial de tabaquismo asociado con la presencia de antracosis pulmonar, engrosamiento septal y bullas enfisematosas comprendió los criterios de inclusión del estudio. La muestra consistió en biopsias de pulmón, diafragma y ECOM. El estudio se realizó mediante análisis microscópico óptico de lâminas histológicas obtenidas de 36 cadáveres con EPOC. El diagnóstico histopatológico fue realizado por un patólogo que desconocía los objetivos del estudio. Hallazgos: En el diafragma, hubo la presencia de tejido adiposo interpuesto, atrofia muscular, eliminación de las fibras musculares y fibrosis. En el ECOM, también se evidenció la eliminación de las fibras musculares, la atrofia muscular, el tejido adiposo interpuesto, la hipertrofia muscular y el engrosamiento de los tendones. Conclusiones: Los cambios encontrados en las biopsias musculares de diafragma y ECOM de los cadáveres con EPOC se evidenciaron como un mecanismo de compensación y/o disfunción del sistema respiratorio debido a alteraciones biomecánicas promovidas por la enfermedad.

Introduction: In chronic obstructive pulmonary disease (COPD), the diaphragm and sternocleidomastoid respiratory muscles (ECOM) work against increased mechanical loads due to limited air flow and changes in chest conformation due to the condition of pulmonary hyperinflation. Objective: To evaluate the histopathological changes present in the lungs and respiratory muscles (diaphragm and ECOM) of the corpses affected by COPD. Materials and methods: This is a blind and descriptive study with analysis of histological images of biopsy. The history of smoking associated with the presence of pulmonary anthracosis, septal thickening and emphysematous bullae included the inclusion criteria of the study. The study was conducted by optical microscopic analysis of histological sheets obtained from 36 corpses with COPD. The histopathological diagnosis was made by a pathologist who did not know the objectives of the study. Results: In the diaphragm, there was the presence of interposed adipose tissue, muscle atrophy, removal of muscle fibers and fibrosis. In ECOM, the elimination of muscle fibers, muscular atrophy, interposed adipose tissue, muscle hypertrophy and thickening of the tendons were also evident. Conclusions: The changes found in the diaphragm and ECOM muscle biopsies of the bodies with COPD were evidenced as a mechanism of compensation and / or dysfunction of the respiratory system due to biomechanical alterations promoted by the disease.

Evaluation by fractal dimension of muscle regeneration after photobiomodulation / Avaliação por meio da dimensão fractal da regeneração muscular após fotobiomodulação

Abstract Introduction: Many treatment modalities are used for muscle tissue recovery. Photobiomodulation is a modality that can be employed to improve the quality of tissue repair. The use of fractal dimension (FD) is an innovative methodology in the quantitative evaluation of treatment efficacy. Objective: Use FD as a quantitative analysis method to evaluate the effect of photobiomodulation of 904 nanometers (nm) in the initial phase of the muscle regeneration process. Method: Thirty male Wistar rats were divided into three groups: Control Group (CG), Injured and Untreated Group (IUT), and Injured and Treated Group (IT). Muscle injury was induced by cryoinjury in the central region of the anterior tibial (AT) belly of the left posterior limb. This was performed by an iron rod that was previously immersed in liquid nitrogen. Applications started 24 hours after the injury and occurred daily for five days. They were performed at two points in the lesion area. The rats were euthanized on the seventh day. The AT muscles were removed and frozen in liquid nitrogen. Then, the histological sections were stained using the Hematoxylin-Eosin (HE) technique and submitted to FD analysis performed by the box-counting method using ImageJ software. The Kolmogorov-Smirnov test was used for data normality, and the Kruskall-Wallis test and Dunn's post-test were used for group comparison (p<0.05%). Results: Differences between IT and IUT groups were statistically significant, and it was possible to observe the reduction of fractability with p=0.0034. Conclusion: FD is a useful tool for the analysis of skeletal muscle disorganization in the initial phase of regeneration and confirms the potentially beneficial effects of photobiomodulation to this process.

Resumo Introdução: Diversas modalidades de tratamento são utilizadas para recuperação do tecido muscular, dentre elas a fotobiomodulação pode ser empregada para melhorar a qualidade da regeneração e a dimensão fractal se apresenta como uma metodologia inovadora na avaliação quantitativa da eficácia do tratamento. Objetivo: Utilizar a dimensão fractal como método de análise quantitativa do efeito do Laser de Arseneto de Gálio (AsGa) na fase inicial do processo de regeneração muscular. Método: Foram utilizados trinta ratos Wistar, machos divididos em: Grupo Controle (CT), Grupo lesado e não tratado (LNT) e Grupo Lesado e tratado (LT). A lesão muscular foi induzida por criolesão na região central do ventre do músculo tibial anterior (TA) do membro posterior esquerdo, por meio de uma haste de ferro previamente imersa em nitrogênio líquido. As aplicações foram iniciadas 24 horas após a lesão, diariamente, durante cinco dias, em dois pontos na área da lesão. No sétimo dia os animais foram eutanasiados; o músculo TA retirado, congelado em nitrogênio líquido e os cortes histológicos corados com a técnica de Hematoxilina-Eosina para serem então submetidos à análise de dimensão fractal realizada pelo método boxcounting através do software Image J. Para a normalidade dos dados utilizou-se Kolmogorov Smirnov, para as comparações teste de Kruskall-Wallis com pós teste de Dunn (p<0,05%). Resultados: A comparação entre LT e LNT foi estatisticamente significativa, sendo possível observar a redução da fractabilidade com p=0,0034. Conclusão: A dimensão fractal é uma ferramenta útil para análise da desorganização músculo esquelética na fase inicial da regeneração e mostra o potencial efeito benéfico da fotobiomodulação nesse processo.

Comparison of the efficacy of losartan, hydrocortisone and acetylsalicylic acid (ASA) in preventing the development of fibrous scar tissue in skeletal muscle / Comparação da eficácia de losartana, hidrocortisona e ácido acetilsalicílico (AAS) na prevenção do desenvolvimento de tecido cicatricial fibroso nos músculos esqueléticos / Comparación de la eficacia de losartán, hidrocortisona y ácido acetilsalicílico (AAS) en la prevención del desarrollo de tejido cicatricial fibroso en los músculos esqueléticos

OBJECTIVE: To analyze fibrous scar tissue inhibition capacity with the use of losartan, hydrocortisone and acetylsalicylic acid. METHOD: The sample consisted of 120 male heterogeneic Wistar rats with a muscle laceration model. The rats were divided into four groups of 30 animals each: control group, losartan group, ASA group and hydrocortisone group. The animals were anesthetized and a 2.5 cm longitudinal incision was made in the left thoracolumbar paravertebral region. The muscles were subjected to a Grade III lesion caused by applying Kelly hemostatic forceps for 60 seconds, followed by sectioning with scissors. The skin was sutured with 3-0 nylon monofilament thread. The animals were placed in individual cages with plenty of food and water. The losartan group received losartan diluted in water at a dose of 0.1 mg/mL (10 mg/kg/day), the ASA Group received a 3 mg/mL ASA solution (300 mg/kg/day), and the hydrocortisone group received a 0.2 mg/mL hydrocortisone solution (20 mg/kg/day). RESULTS: The control, losartan, hydrocortisone and aspirin groups had a fibrotic area of 0.95 ± 0.35 mm, 0.55 ± 0.34 mm, 0.93 ± 0.33 mm, and 0.66 ± 0.36 mm, respectively. We observed a significantly smaller fibrotic area in the losartan group compared to the control (p=0.01) and hydrocortisone (p=0.01) groups. There were no significant differences among the other groups. CONCLUSION: The healing of striated skeletal muscle produced less fibrous scar tissue when exposed to losartan in comparison to the control group or the hydrocortisone group. Level of Evidence I; Randomized double-blind placebo-controlled study.

OBJETIVO: Analisar a capacidade de inibição de formação de tecido cicatricial fibroso com losartana, hidrocortisona e AAS. MÉTODOS: A amostra consistiu em 120 ratos Wistar heterogênicos machos com modelo de laceração muscular. Os ratos foram distribuídos em quatro grupos de 30 animais: grupo controle, grupo losartana, grupo AAS e grupo hidrocortisona. Os animais foram anestesiados e submetidos a uma incisão em sentido longitudinal de 2,5 cm de extensão na região paravertebral toracolombar esquerda, e os músculos sofreram uma lesão grau III com pinça hemostática de Kelly durante 60 segundos e posterior secção com tesoura. A pele foi suturada com nylon monofilamentar 3-0. Os animais foram colocados em gaiolas individuais, com água e alimento à vontade. O grupo losartana recebeu losartana diluída em água na dose de 0,1 mg/ml (10 mg/kg/dia), o grupo AAS recebeu solução de AAS 3 mg/ml (300 mg/kg/dia), o grupo hidrocortisona recebeu solução de hidrocortisona 0,2 mg/ml (20 mg/kg/ dia). RESULTADOS: Os grupos controle, losartana, hidrocortisona e AAS apresentaram área fibrótica de0,95 ± 0,35 mm, 0,55 ± 0,34 mm, 0,93 ± 0,33 mm, 0,66 ± 0,36 mm, respectivamente. Observou-se área fibrótica significativamente menor do grupo losartana em comparação com o grupo controle (p = 0,01) e hidrocortisona (p = 0,01). Nos demais grupos não houve diferença significativa. CONCLUSÃO: A cicatrização do músculo estriado esquelético produziu menos tecido cicatricial fibroso quando exposto à losartana do que quando comparado com o grupo controle ou o grupo hidrocortisona. Nível de Evidência I; Estudo duplo-cego randomizado controlado por placebo.

OBJETIVO: Analizar la capacidad de inhibición de formación de tejido cicatricial fibroso con losartán, hidrocortisona y AAS (ácido acetilsalicílico). MÉTODOS: La muestra consistió en 120 ratas Wistar heterogéneas machos con modelo de laceración muscular. Las ratas fueron distribuidas en cuatro grupos de 30 animales: grupo control; grupo losartán; grupo AAS y grupo hidrocortisona. Los animales fueron anestesiados y sometidos a una incisión longitudinal de 2,5 cm de extensión en la región paravertebral toracolumbar izquierda y los músculos sufrieron una lesión de grado III con pinza hemostática de Kelly durante 60 segundos y posterior sección con tijera. La piel se suturó con monofilamento de nylon 3-0. Los animales fueron dispuestos en jaulas individuales con abundante comida y agua. El grupo losartán recibió losartán diluido en agua a una dosis de 0,1 mg/ml (10 mg/kg/día), el grupo AAS recibió solución de AAS de 3 mg/ml (dosis 300 mg/kg/día), el grupo hidrocortisona recibió solución hidrocortisona de 0,2 mg/ml (20 mg/kg/día). RESULTADOS: Los grupos control, losartán, hidrocortisona y AAS mostraron área fibrótica de 0,95 ± 0,35 mm, 0,55 ± 0,34 mm, 0,93 ± 0,33 mm, 0,66 ± 0,36 mm, respectivamente. Se observó área fibrótica significativamente menor del grupo losartán en comparación con el grupo control (p = 0,01) e hidrocortisona (p = 0,01). En los demás grupos no hubo diferencias significativas. CONCLUSIÓN: La cicatrización del músculo estriado esquelético produjo menos tejido cicatricial fibroso cuando fue expuesto a losartán que cuando fue comparado con el grupo control o el grupo hidrocortisona. Nivel de Evidencia I; Estudio doble ciego aleatorio controlado por placebo.

Use of zebrafish ( Danio rerio ) embryos as a model to assess effects of mercury on developing skeletal muscle: a morphometric and immunohistochemical study / Uso de embriones de pez cebra ( Danio rerio ) como modelo para evaluar los efectos del mercurio en el desarrollo del músculo esquelético: un estudio morfométrico e inmunohistoquímico

Exposure to mercury in the environment continues to be a significant worldwide concern, especially for developing embryos and fetuses. While extensive research effort has focused on the effects of mercury on the developing nervous system, much less is known concerning adverse effects of mercury on other organ systems, including the development of skeletal muscle. We exposed developing zebrafish embryos to a range of concentrations of mercuric chloride (100 to 400 µg/liter or ppb) and compared them to control embryos (0 µg/L mercuric chloride). Embryos were examined at 48 hours post fertilization (hpf) for morphometry and morphological deformities of skeletal muscle fibers in the trunk and tail. Embryos exposed to 400 ppb mercuric chloride showed decreased trunk and tail areas compared to control embryos. A dose-dependent reduction in muscle fiber length was observed, and exposure to all concentrations of mercuric chloride used in this study resulted in decreased muscle fiber immunohistochemical staining with anti-myosin antibodies. Irregular muscle fiber diameters, twisted muscle fibers, and degenerated muscle fibers were observed in sections of embryos stained with eosin at the higher exposure concentrations. Evidence presented in this study suggests that exposure to even low concentrations of mercuric chloride adversely affects skeletal muscle fiber development or muscle fiber integrity, or both.

La exposición al mercurio en el medio ambiente sigue siendo una preocupación mundial importante, especialmente para el desarrollo de embriones y fetos. Si bien un amplio esfuerzo de investigación se ha centrado en los efectos del mercurio en el sistema nervioso en desarrollo, se sabe mucho menos sobre los efectos adversos en otros sistemas orgánicos, incluido el desarrollo del músculo esquelético. Expusimos embriones de pez cebra en desarrollo a un rango de concentraciones de cloruro de mercurio (100 a 400 mg / l o ppb) y los comparamos con embriones de control (0 mg / L de cloruro de mercurio). Los embriones se examinaron a las 48 horas después de la fertilización (HPF) pararealizar la morfometría y verificar las deformidades morfológicas de las fibras del músculo esquelético en el tronco y la cola. Los embriones expuestos a 400 ppb de cloruro de mercurio mostraron una disminución de las áreas del tronco y la cola en comparación con los embriones de control. Se observó una reducción dependiente de la dosis en la longitud de la fibra muscular, y la exposición a todas las concentraciones de cloruro de mercurio utilizadas en este estudio, dio como resultado una tinción inmunohistoquímica de fibra muscular disminuida con anticuerpos anti-miosina. Se observaron diámetros irregulares de fibras musculares, fibras musculares retorcidas y fibras musculares degeneradas en secciones de embriones teñidos con eosina en las concentraciones de exposición más altas. La evidencia presentada en este estudio sugiere que la exposición incluso a bajas concentraciones de cloruro mercúrico afecta negativamente el desarrollo de la fibra del músculo esquelético o la integridad de la fibra muscular, o ambas.

Retroperitoneal dedifferentiated liposarcoma with rhabdomyoblastic differentiation: a clinicopathological analysis / 中华病理学杂志

Objective@#To investigate the clinicopathological features, differential diagnosis, treatment and prognosis of dedifferentiated liposarcoma with rhabdomyoblastic differentiation.@*Methods@#Six cases of retroperitoneal dedifferentiated liposarcoma with rhabdomyoblastic features were collected from December 2014 to August 2017 at Peking University International Hospital. The clinical manifestations, histomorphology, immunophenotype, treatment and follow-up data were analyzed, and relevant literature reviewed.@*Results@#The six patients included two males and four females, with age range of 47 to 66 years (mean 56 years). One case was primary and the five cases were recurred; four cases received radiotherapy and/or chemotherapy. The tumor diameters were 10 to 30 cm. Microscopically, the dedifferentiated areas were well demarcated from the well-differentiated areas, and resembled malignant fibrous histiocytoma, fibrosarcoma or solitary fibrous tumor with obvious mitotic figures or necrosis. Rhabdomyoblastic cells made up 10% to 30% of dedifferentiated area, and were scattered or focally distributed, being rounded, band-like or spindled, mostly with abundant eosinophilic cytoplasm. No striated structure was found, and the nucleis were rounded, oval or irregular shape with central or eccentric prominent nucleoli. Rare rhabdomyoblastic cells were lymphocytoid. The tumors encroached the muscular layer of intestinal wall in two cases and perirenal adipose tissue in one case. By immunohistochemical staining, the rhabdomyoblastic cells of all cases were all positive for desmin, myogenin, myoD1 and SMA; S-100 protein was expressed in one case (1/6). Well-differentiated area in two cases and dedifferentiated areas in all six cases were positive for MDM2, CDK4 and p16. After resection of the tumor and adjacent organs, one case recurred three months later, but there was no distant metastasis.@*Conclusions@#Dedifferentiated liposarcoma with rhabdomyoblastic differentiation is a rare dedifferentiated liposarcoma. Pathological diagnosis is based on morphology, with supplementary immunohistochemical or molecular evaluation for further differential diagnosis. Multiple relapses may occur after surgical ablation plus adjuvant therapy.

The effects of full marathon on hemodynamics related to cardiac electrophysiology of marathon amateurs / 中华急诊医学杂志

Objective To observe and assess the effects of full marathon on hemodynamics and cardiac electrophysiology of marathon amateurs without adverse event after the race.Methods Fiftyone subjects were included in the final analysis of the study,blood pressure,heart rate,body surface electrocardiogram (ECG) of all subjects under static status before the race and within (15-30) min after the race were detected,and sufficient amounts of the peripheral blood and the radial arterial blood specimens of all subjects under static status before the race and within (15-30) min after the race were collected instantly.The peripheral blood was used for measuring markers of muscle injury and NT-proBNP,and the radial arterial blood was taken for blood gas analysis.The QTc interval,QRS,PR interval,and QTd interval were recorded from the 12-lead ECG report.Results Compared with those under static status before the race,the systolic blood pressure,diastolic blood pressure,mean arterial blood pressure and heart rate of all the subjects within (15-30) min after the race were significantly higher (P＜0.05).When the markers of striated muscle injury were compared before and after the competition,levels of CK,cTNI,LDH,and myoglobin after the race were significantly increased compared with them under static status before the race (P ＜0.05),and the level of NT-proBNP after the race was also significantly increased compared with it before the race (P＜0.05).When blood gas analysis before the race was compared with that after the race,the PH values after race were significantly lower than it before race (P＜0.05).The level of lactic acid after the race was significantly higher than it before race (P＜0.05).After the race,the levels of PCO2,SBE and HCO3-decreased significantly compared with those before race (P＜0.05),and the QTc and QTd intervals after the race increased significantly compared with those before the race,however,the QTc interval and QTd interval for all subjects before and after the competition were within the normal range.Conclusions Full marathon significantly affect the myocardial electrophysiological markers of healthy amateur athletes without chronic diseases,but those markers fluctuate within the normal range.

Morphometric study of muscle fibers in rats submitted to strength training and growth hormone / Estudio morfométrico de las fibras musculares de ratas sometidos a entrenamiento de la fuerza muscular y hormona del crecimiento

The aim of the present study was to observe the changes in the muscle tissue of rats after application of growth hormone (GH) and performing a strength training protocol (ST). In total, 40 male Wistar rats, 60 days old, were used, divided into four groups: control (C), control and application of GH (GHC), strength training (T), and strength training with the application of GH (GHT). The physical training protocol (PT) was composed of four series of 10 jumps in water, 3x/week, with an overload of 50 % of body weight for four weeks. GH was administered intraperitoneally at a dose of 0.2 IU/Kg to the GHC and GHT groups and saline (0.9 % sodium chloride) to the C and T groups. After four weeks of PT, the animals were euthanized and samples taken from the Soleus muscle. Histological sections were produced with a thickness of 5 mm and stained with hematoxylin-eosin (HE) and nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR). The markings for determining the measurement of the smallest diameter of muscle fibers (MF) were carried out using the software (AuxioVisionRel 4.8-Carl Zeiss® and NIS-Elements D3.0-SP7-Nikon®). After obtaining the data, the Shapiro-Wilk test for normality was performed and then the nonparametric Kruskal-Wallis with Dunn post-test were used for analysis of MF and the Student t test for the analysis of intragroup body weights. All procedures adopted a 5 % significance value (p <0.05) and were performed using the software SPSS 22.0 for Windows®. It was observed that both the GH and PT were able to generate increased diameter of MF (C:31.81±6.35; GHC:36.88±6.38; T:38.38± 6.94; GHT:36.89±7.16). Moreover, when analyzing the type, a significant increase was found only in the fast twitch MF (C:33.78±7.78; GHC:37.80±6.03; T:38.53±6.94; GHT:37.98±7.65) when compared to the slow twitch (C:25.93±6.66; GHC:26.95±8.03; T:26.24±6.90; GHT:27.20±5.77).

El objetivo de la investigación fue observar las modificaciones en tejido muscular esquelético de ratas después de la aplicación de la hormona del crecimiento (GH) y posterior entrenamiento de fuerza muscular (EFM). Fueran utilizadas 40 ratas Wistar, con 60 días de edad, distribuidas en: control (C), control y aplicación de la hormona del crecimiento (GHC), entrenamiento de fuerza muscular (T), y entrenamiento de fuerza muscular y hormona del crecimiento (GHT). El protocolo de entrenamiento (PT) fue compuesto por cuatro series de diez saltos acuáticos, 3x/semana, con sobrecarga de 50 % del peso corporal, por cuatro semanas. El GH fue aplicado de forma intraperitoneal con una dosis de 0,2UI/kg en grupos GHC y GHT y solución salina (0,9% clorhidrato de sodio) en grupos C y T. Después de cuatro semanas del PT, los animales fueron sacrificados y retirados los músculos sóleos. Se realizaron cortes de 5 µm los que fueron coloreados con Hematoxilina y Eosina (HE), posteriormente fueron sometidos a reacción con nicotinamida adenina dinucleotide tetrazolium reductasa (NADH-TR). Después de la obtención de los datos, fue utilizado la prueba del Shapiro-Wilk para la verificación de la normalidad de los datos y se usó el ensayo de Kruskal-Wallis con pos verificación del Dunn para análisis de las fibras musculares (FM) y prueba t del Student para la análisis del peso corporal entre los grupos. Todos los procedimientos fueron establecidos con valor de la significancia de 5 % (p<0,05) y realizados con el software SPSS 22.0 for Windows®. Fue verificado que tanto lo GH cuanto lo PT fueran capaces de proporcionar el aumento en el diámetro de las FM (C:31.81±6.35; GHC:36.88±6.38; T:38.38±6.94; GHT:36.89±7.16). En relación al tipo de fibras se observó aumento significativo solamente en las FM de contracción rápida (C:33.78±7.78; GHC:37.80±6.03; T:38.53±6.94; GHT:37.98±7.65) cuando se comparó con las FM de contracción lenta (C:25.93±6.66; GHC:26.95±8.03; T:26.24±6.90; GHT:27.20±5.77).

High energy Gallium Arsenide laser does not facilitate collagen alteration in muscle skeletal extracellular matrix: experimental study / Laser de Arseneto de Gálio com alta energia não promove alteração colágena da matriz extracelular no músculo esquelético: estudo experimental

Abstract Introduction: Low intensity laser therapy has proven effective in treating different tissues, reducing inflammation, preventing the formation of fibrous tissue, and promoting muscle regeneration. Objective: To evaluate the effect of low intensity laser therapy, seven days after the injury, and verify whether the radiated energy chosen influences the formation of fibrous tissue. Methods: Thirty Wistar rats, adult male, average body weight 210-340 g were used. The animals were randomized into three groups: control group, untreated injured group (L), and injured and treated group (LT). After anesthetizing the animals, muscle injury was induced by freezing (cryoinjury) in the central region of the tibialis anterior muscle belly (TA) on the left hind limb, through an iron rod previously immersed in liquid nitrogen. A Gallium Arsenide laser, wavelength 904 nm was used. The applications were initiated 24 hours after injury, daily, for five days, at two points in the lesion area. After 7 days, the animals were euthanized; the TA muscle of the left hind limb was removed and frozen in liquid nitrogen and the obtained histological sections were subjected to Sirius Red staining. Results: Histological analysis showed no significant difference in relation to the area of fibrosis in the LT and L groups. Conclusion: The results suggest that the energy density of 69 J/cm² and final energy (4.8 joules) did not promote alterations in the area of collagen in the skeletal muscle extracellular matrix.

Resumo Introdução: A Laserterapia de Baixa Intensidade tem se mostrado eficaz no tratamento de diferentes tecidos, diminuindo o processo inflamatório, prevenindo a formação de tecido fibroso e promovendo a regeneração muscular. Objetivo: Avaliar o efeito da Laserterapia de Baixa Intensidade, 7 dias após a lesão e verificar se a energia irradiada escolhida tem influência na formação de tecido fibroso. Métodos: Foram utilizados trinta ratos Wistar, machos, adultos, peso corporal médio de 210-340 g. Os animais foram randomizados em três grupos: Grupo Controle, Grupo lesado não tratado (L) e o Grupo lesado e tratado (LT). Após anestesia dos animais, a lesão muscular foi induzida por congelamento (criolesão) na região central do ventre do músculo tibial anterior (TA) do membro posterior esquerdo, por meio de uma haste de ferro previamente imersa em nitrogênio líquido. Foi utilizado o laser de Arseneto de Gálio, comprimento de onda de 904 nanômetros. As aplicações foram iniciadas 24 horas após a lesão, diariamente, durante cinco dias, em dois pontos na área da lesão. Aos 7 dias, os animais foram eutanizados; o músculo TA do membro posterior esquerdo foi retirado e congelado em nitrogênio líquido e os cortes histológicos obtidos foram submetido a coloração Picrosirius Red. Resultados: A análise histológica mostrou que não houve diferença significativa em relação á área da fibrose do LT e Grupo L. Conclusão: Os resultados sugerem que a densidade de energia de 69 J/cm² e energia final (4,8 joules) não promoveu alteração na área do colágeno da matriz extracelular do músculo esquelético.

Morphological study of the iris musculature in diurnal and nocturnal raptors / Estudio morfológico de la musculatura del diafragma en aves rapaces diurnas y nocturnas

In literature it is established that the iris musculature consists of striate muscle fibers in birds while in mammals it consists of smooth muscles. Some authors report the presence of smooth muscle tissue also in the iris of some species of birds. In the present study we report on the iris muscle tissues (type of tissue, direction and mean diameter of muscle fibers or cells) in five species of Accipitriformes (diurnal raptors) and four species of Strigiformes (nocturnal raptors) because they show different way of life depending of their predatory behavior. This morphological study was carried out from raptors died or euthanized at the Wild Life Rescue Centre of Sea and Water birds in Livorno (Italy). From histological examination of iris serial radial sections we find both striated and smooth musculature even if with marked differences among analyzed species, not directly correlated with diurnal or nocturnal lifestyle. Striated fibers are always present, mainly with cross direction, throughout the iris stroma, while the histological differences concern the smooth cells. Indeed, harrier and sparrow hawk (Accipitriformes) and great horned owl and little owl (Strigiformes) show a compact layer of cross smooth muscle cells throughout the iris stroma. In the other species analyzed smooth muscle cells are slightly detectable as scattered or not detectable. Since the cross smooth muscle tissue allows to maintain a myotic state for extended periods of time, our results might be correlated more to the predatory behavior than the taxonomic order.

En la literatura, se establece que la musculatura del iris se compone de fibras musculares estriadas en las aves, mientras que en los mamíferos, la forman los músculos lisos. Algunos autores informan también de la presencia de tejido muscular liso en el iris de algunas especies de aves. El presente estudio informa sobre los tejidos musculares del iris (tipo de tejido, la dirección y diámetro de las fibras musculares o células) en cinco especies de Accipitriformes y cuatro especies de Strigiformes que muestran diferentes hábitos en función de su comportamiento depredador. Este estudio morfológico se realizó en aves rapaces que murieron o fueron eutanasiadas en el Centro de Vida Salvaje de Rescate de Aves Marinas y Acuáticas de Livorno (Italia). El examen histológico de secciones seriadas radiales del iris mostró la presencia tanto de musculatura estriada como lisa, aunque con marcadas diferencias entre las especies analizadas, pero sin correlación directa con el estilo de vida diurna o nocturna. Las fibras estriadas estuvieron siempre presentes, principalmente en dirección transversal a lo largo del estroma del iris, mientras que las diferencias histológicas fueron de las células lisas. Tanto el aguilucho y el gavilán (Accipitriformes) como el buho real y el mochuelo (Strigiformes) mostraron una capa compacta de células musculares lisas transversales en todo el estroma del iris. En las otras especies analizadas, las células musculares lisas fueron ligeramente detectables de manera dispersa o no detectables. Dado que el tejido del músculo liso transversal permite mantener un estado miótico durante largos períodos de tiempo, nuestros resultados podrían estar más correlacionados con el comportamiento depredador, y no con el orden taxonómico.

Comparison of Double Maddox Rod Test and Bagolini Striated Lens Test for Superior Oblique Palsy

PURPOSE: We compared the results of the double Maddox rod test (DMRT), which is commonly performed in clinics as a subjective torsion test for superior oblique muscle palsy, with those of the Bagolini striated lenses test (BSLT) in a least dissociating condition to predict the cyclofusional capacity. METHODS: Twenty-five patients with acquired superior oblique muscle palsy were tested for degree of subjective torsion with DMRT and BSLT in primary position and down-gaze in Daegu Catholic University Hospital from May 2014 to March 2015. DMRT was performed in a dark room and BSLT in a lighted room. RESULTS: Mean extorsional degree in primary position was 3.40 ± 2.58° on DMRT and 1.88 ± 2.92° on BSLT, a significant difference (p = 0.000). In down-gaze, mean extorsional degree was 4.16 ± 2.90° with DMRT and 2.40 ± 2.90° with BSLT (p < 0.001). CONCLUSIONS: The subjective torsional measurement with BSLT was significantly smaller than with DMRT, and the cyclofusional capacity in patients with acquired superior oblique palsy was 1.5° in primary position and 1.8° in down-gaze. BSLT is helpful in addition to DMRT and fundus photograph for the evaluation of cyclotropia in patients with superior oblique muscle palsy, and this test may yield clinically important information for predicting the cyclofusional capacity of patients with superior oblique muscle palsy.

Effects of 14 weeks resistance training on muscle tissue in Wistar rats / Efecto de 14 semanas de entrenamiento de resistencia en el tejido muscular de ratas Wistar

The objective of the present study was to analyze the effects of 14 weeks of resistance training on muscle tissue in Wistar rats. 20 male Wistar rats were used in the study; 10 allocated to the untrained group (Group 1) and 10 to the trained (Group 2). The physical training (PT) program consisted of four sets of ten water jumps, three times a week for 14 weeks. A progressive increase in load was applied from the14nd to the 42nd day. Following this, the animals were euthanized with an overdose of potassium chlorate (100 mg/kg) applied intraperitoneally. The ventral portion of the gastrocnemius muscle was removed for histological processing. The muscles were frozen in liquid nitrogen and cut into thicknesses of 5 µm using a rotative microtome. The sections were stained with hematoxylin-eosin for general analysis of the structure of muscles and analysis of the area of muscle fibers. The reaction with NADH-TR was utilized for differentiation between fast twitch (FT) and slow twitch (ST) fibers. The sections subjected to staining and histochemical reactions were observed in normal and polarized light and photomicrographed using a microscope (Zeiss®). The measurement of muscle fibers was performed using AxioVision software (Zeiss®). Statistical analysis was performed using the Student t test for analysis of the samples average. An average area of 5061.29 µm2 for Group 1 versus 5768.93 µm2 for Group 2 was observed. It can be concluded that 14 weeks of training with water jumps was effective in increasing muscle area. An increase in transverse area section (TAS) of ST and FT was also verified in the trained group.

El objetivo fue investigar los efectos de 14 semanas de entrenamiento de resistencia sobre el tejido muscular de ratas Wistar. Fueron utilizadas 20 ratas, 10 en el grupo sin entrenamiento (Grupo 1) y 10 con entrenamiento (Grupo 2). El programa de entrenamiento físico estaba compuesto de cuatro series con 10 saltos acuáticos, tres veces en la semana, durante 14 semanas. Un aumento progresivo de la carga fue aplicado desde el día 14 al día 42. Los animales fueron eutanasiados con clorhidrato de potasio (100 mg/kg) intraperitoneal. La parte ventral del músculo gastrocnemio fue removida para el análisis histológico. La musculatura fue congelada en nitrógeno líquido y cortada con 5 µm de espesor con micrótomo rotatorio. La coloración fue H-E para el análisis del músculo y área en las fibras musculares. La reacción com NADH-TR fue utilizada para la comparación entre las fibras rápidas (FR) y fibras lentas (FL). Las reacciones histoquímicass se observaron bajo microscópio de luz (Zeiss®) y sobre las microfotografias obtenidas se realizaron las mediciones con el programa Axio Vision (Zeiss®). El análisis estadístico se realizó con la prueba t de student para comparación de medias. Se observó una media de 5061,29 µm2 en el Grupo 1 y 5768,93 µm2 en Grupo 2. Es posible concluir que 14 semanas de programa de entrenamiento físico con 10 saltos acuáticos son capaces de aumentar el área del músculo. Un aumento del área transversal de las FR y FL fue observado en el grupo 2.

Expressions of histamine receptors in pediatric mid-urethral striated muscles and mouse striated myogenesis / 中华实用儿科临床杂志

Objective To explore the expressions of histamine receptor subtypes (H1, H2, H3, H4 receptor) in children's mid-urethral striated muscles and during mouse C2C12 striated myogenesis.Methods Children's mid-urethral striated muscle samples were paraffin embedded and tissue sections were made, then immunohistochemical staining was used to check H1, H2, H3, H4 receptors.C2C12 myogenesis was induced, the early differentiation early markers of desmin, middle marker of myogenin, late marker of myosin heavy chain and histamine 4 receptor subtype mRNA were checked by quantitative real-time polymerase chain reaction.Immunofluorescence staining was done to check 3 differentiation markers and histamine H3 receptor protein.Results During myogenesis, the expression of desmin mRNA in the differentiation of 2,4,6 days were 12,68,60 times as many as that of the undifferentiated myoblasts;the expression of myogenin mRNA in the differentiation of 2,4,6 days were 631,1 408,914 times as many as that of the undifferentiated myoblasts;the expression of myosin heavy chain mRNA in the differentiation of 2,4,6 days were 7 718,9 448,286 288 times as many as that of the undifferentiated myoblasts.The expression level of H1 receptor mRNA in the differentiation of 6 days was about 25％ to undifferentiated cells;the expression of H2 receptor mRNA in undifferentiated cells and differentiated cells groups had no significant difference (F =1.47, P ＞ 0.05);the expression of H3 receptor mRNA in the differentiation of 2,4,6 days was 28,103,198 times to undifferentiated cells;H4 receptor mRNA was not detected.In immunofluorescence staining, H3 receptor protein staining intensity increased with the differentiation.Immunohistochemistry of pediatric urethral striated staining indicated that H1, H2, H3 receptor staining was positive,H1 receptor showed strong positive staining, H3 receptor moderate positive staining,and H2 receptor showed weak positive staining.Conclusions Histamine receptor subtypes of H1 receptor, H2 receptor and H3 receptor were found during mouse striated myogenesis and in the children's mid-urethral striated muscles.The increasing expression of H3R with myogenesis might indicate it plays a role in mature striated muscle cells.

Two Cases of Rhabdomyomatous Mesenchymal Hamartoma / 대한피부과학회지

Rhabdomyomatous mesenchymal hamartoma is a rare skin lesion composed of a haphazard arrangement of skeletal muscle, adipocytes, and collagen. Lesions usually present as a solitary sessile papule or nodule on the head and neck in childhood. The etiology of this skin lesion is not clear, but it is thought to be caused by a migration error of the embryonic mesodermal tissues or a genetic defect predisposing to the formation of hamartoma. It may occur as part of Delleman syndrome or congenital malformations like thyroglossal duct cysts, low set ears, and sclerocornea. Herein, we present two cases of rhabdomyomatous mesenchymal hamartoma, including a 20-year-old man who had two asymptomatic erythematous papules on the chin since childhood and a 58-year-old woman with an asymptomatic solitary erythematous sclerotic plaque on the chin for 2 years. Histopathologically, the lesions exhibited normal epidermis, and mature striated muscle fibers arranged randomly within the dermis. Physical examination revealed no congenital abnormalities.

Standardization of metachromatic staining method of myofibrillar ATPase activity of myosin to skeletal striated muscle of mules and donkeys / Padronização do método de coloração metacromático da atividade da miosina ATPase miofibrilar para músculo estriado esquelético de muares e asininos

This study aims at standardizing the pre-incubation and incubation pH and temperature used in the metachromatic staining method of myofibrillar ATPase activity of myosin (mATPase) used for asses and mules. Twenty four donkeys and 10 mules, seven females and three males, were used in the study. From each animal, fragments from the Gluteus medius muscle were collected and percutaneous muscle biopsy was performed using a 6.0-mm Bergstrõm-type needle. In addition to the metachromatic staining method of mATPase, the technique of nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) was also performed to confirm the histochemical data. The histochemical result of mATPase for acidic pre-incubation (pH=4.50) and alkaline incubation (pH=10.50), at a temperature of 37ºC, yielded the best differentiation of fibers stained with toluidine blue. Muscle fibers were identified according to the following colors: type I (oxidative, light blue), type IIA (oxidative-glycolytic, intermediate blue) and type IIX (glycolytic, dark blue). There are no reports in the literature regarding the characterization and distribution of different types of muscle fibers used by donkeys and mules when performing traction work, cargo transportation, endurance sports (horseback riding) and marching competitions. Therefore, this study is the first report on the standardization of the mATPase technique for donkeys and mules...

O presente estudo objetivou padronizar o pH e a temperatura da pré-incubação e incubação do método de coloração metacromática de myofibrillar atividade ATPase da miosina (mATPase) utilizada para asininos e muares. Vinte e quatro jumentos e 10 muares, sete machos e três fêmeas, foram usados no estudo. De cada animal, fragmentos do músculo Gluteus medius foram coletados e biópsia muscular percutânea foi realizada por meio de uma agulha Bergstrõm tipo de 6,0 mm. Em adição ao método de coloração metacromática de mATPase, a técnica de nicotinamida adenina dinucleótido tetrazólio redutase (NADH-TR) foi também realizada para confirmar os dados histoquímicos. O resultado histoquímico da mATPase por pré-incubação ácida (pH=4,50) e incubação alcalina (pH=10,50), a uma temperatura de 37ºC, foi o que proporcionou a melhor diferenciação das fibras coradas com azul de toluidina. As fibras musculares foram identificadas de acordo com as seguintes cores: tipo I (oxidativa, azul claro), tipo IIA (oxidativo-glicolítico, azul intermediário) e tipo IIX (glycolytic, azul escuro). Na literatura, não foram encontradas publicações pertinentes à caracterização e distribuição dos diferentes tipos de fibras musculares utilizadas pelos asininos e muares nos trabalhos de tração, no transporte de cargas, em provas esportivas de resistência (cavalgadas) e concursos de marcha. Dessa forma, essa pesquisa é o primeiro relato sobre padronização da técnica de mATPase para muares e asininos...

Hamartoma mesenquimal rabdomiomatoso: um relato de caso / Rhabdomyomatous mesenchymal hamartoma: a case report

The rhabdomyomatous mesenchymal hamartoma (RMH) is a rare type of hamartoma, composed of randomly arranged striated muscle fibers in dermis and subcutaneous tissue, associated with normal mesenchymal elements. Our objective is to report a case of this rare entity that occurred in the nasal dorsum of a 4-year-old child...

O hamartoma mesenquimal rabdomiomatoso (HMR) representa um raro tipo de hamartoma composto por fibras musculares estriadas dispostas aleatoriamente em derme e tecido subcutâneo, associadas a elementos mesenquimais normais. O nosso objetivo é relatar um caso desta rara entidade que ocorreu no dorso nasal de uma criança de 4 anos...

Intoxicação espontânea por Senna obtusifolia em bovinos no Pantanal Sul-Mato-Grossense / Spontaneous poisoning by Senna obtusifolia in cattle of the southern Pantanal

Descreve-se um surto de intoxicação por Senna obtusifolia em bovinos no estado de Mato Grosso do Sul, na região do Pantanal. Em um lote de 313 novilhas, 165 adoeceram e morreram (coeficientes de morbidade de 52,7% e de letalidade de 100%). Os bovinos permaneceram no piquete infestado pela planta por 37 dias. Os sinais clínicos consistiram em relutância em movimentar-se, andar trôpego (incoordenação), decúbito esternal permanente, diminuição do tônus de língua, estado comportamental em alerta, mioglobinúria caracterizada por urina castanho-escuro e fezes ressecadas com ou sem muco (ocasionalmente diarreicas com estrias de sangue). As principais alterações macroscópicas observadas nos 12 bovinos necropsiados estavam nos músculos esqueléticos dos membros pélvicos e foram caracterizadas por graus variáveis de palidez nos grupos musculares. Histologicamente, a lesão mais relevante encontrada foi degeneração e necrose segmentar multifocal nos músculos estriados esqueléticos (miopatia degenerativa tóxica multifocal polifásica). O diagnóstico da intoxicação baseou-se na epidemiologia (massa de forragem e de planta tóxica, análise da lotação do piquete e análise da precipitação pluviométrica), no quadro clínico dos animais e nos achados de necropsia e histopatologia.

Senna sp. poisoning in livestock has been reported in several occasions in Brazil usually from southern Brazil and involving S. occidentalis as the culprit. The objective of this study is to report the occurrence of an outbreak of S. obtusifolia poisoning in cattle in the Pantanal Region of Mato Grosso do Sul, Brazil. In a herd of 313 heifers, 165 were affected and died (morbidity rate of 52.7% and lethality rate of 100%). The 313 heifers remained in the paddock infested by S. obtusifolia for 37 days. Clinical signs consisted of reluctance to move, incoordination, permanent sternal recumbency, decrease in the tonus of the tongue, alertness, myoglobinuria characterized by dark brown urine, and dry stools with or without mucus; or occasionally diarrhea with streaks of blood. The main gross findings in 12 necropsied cattle were in the skeletal muscles of the hind limbs, and were characterized by varying degrees of paleness of muscle groups. Histologically, the most relevant lesion was segmental multifocal degeneration and necrosis in striated skeletal muscles (multifocal lypolyphasic toxic degenerative myopathy). The epidemiological, clinical and pathological data allowed to conclude for the diagnosis of poisoning by S. obtusifolia in this outbreak.

Analysis of the impact of ultrasographer′s experience in diagnosing porcine striped muscle injury from thermal and chemical factors / 中华医学超声杂志（电子版）

Objective To investigate the ultrasonic and pathological features of porcine striped muscle injury from thermal and chemical factors respectively, and to analyze the limitation of ultrasound diagnosis given by doctors with different skill levels. Methods An experimental study using fresh porcine striped muscle in vitro was designed, where the injury were caused by microwave ablation (2 450 MHz) and Anhydrous acetic acid (99.8%) injection separately. Blind to pathologic results, the two-dimensiona sonograms taken from each model were analyzed by sonographers with different skill levels independently. Finally, the diagnoses were evaluated and compared among them. Results Two-dimensional sonograms showed distinct changes of the textures in both injury models, which was characterized as the disappearance of regular tissue structure. However, the corresponding histopathology revealed obvious differences between the two interventions on ultrasonograms. There was no statistical difference between chief physician and attending doctor (both of them had over 5-year experiences on skeletal muscle ultrasound ) in identifying the ultrasonic features of boundary, shape and muscle texture (Kappa=0.933, 0.845, 0.789;Kappa=0.790, 0.935, 0.865, all P<0.05). Compared with residents′diagnosis, there were signiifcant differences in identifying the ultrasonic features of echo level and muscle texture in both injury models:Echo level in thermal injury group:chief physician vs residents, Kappa=0.323;attending doctor vs residents, Kappa=0.297. Texture feature in thermal injury group:chief physician vs residents, Kappa=0.259;attending doctor vs residents, Kappa=0.112. Texture feature in chemical injury group:chief physician vsresidents, Kappa=0.253;attending doctor vs residents, Kappa=0.070. Conclusions Microwave ablation and Anhydrous acetic acid can cause different histopathologic changes in correspondence with various features on two-dimensional sonograms. But ultrasonographers with different skill levels leads to signiifcant variations in identiifcation and qualitative diagnosis, which is impossible to be quantitatively analyzed. Chief physician and attending doctor can draw a consistent conclusion and demonstrate the ultrasounic characteristics in porcine striped muscle injury model from thermal or chemical factors.

Low-frequency magnetic fields promote neovascularization in a rabbit model of atherosclerosis combined with limb ischemia / 中国组织工程研究

BACKGROUND:Studies on basic research of magnetic treatment of limb ischemic disease are not much, because poor compliance of animals and the stability of the magnetic field strength are difficult to control, resulting in big experimental error and decreased credibility of the results. For this kind of problem, experimental study on low-frequency electromagnetic magnetic cages for treatment of ischemic limbs was conducted, thus overcoming the two major issues of poor compliance of animals and difficult control of the stability of magnetic field strength. OBJECTIVE:To investigate the effects of self-made low-frequency magnetic fields of rabbit cages on neovascular growth-promoting factor of rabbits with limb ischemia. METHODS:A total of 96 rabbit models of atherosclerosis were constructed, numbered and randomly divided into ischemia group and non-ischemia group (12 treatment combination in each group). Experiments in each group were performed four times according to the requirement of factorial design. Electromagnetic field intensity factor A (0, 3, 6, 12 mT) and the time factor B (3, 5, 7 days) were set. RESULTS AND CONCLUSION:Low-frequency magnetic field could apparently promote hypoxia inducible factor-1α, vascular endothelial growth factor and CD34 expression in ischemic limb of rabbits. Electromagnetic field intensity factor A was a key factor for contributing to the expression of hypoxia inducible factor-1α, vascular endothelial growth factor and CD34, and the time factor B was secondary factor. Low-frequency magnetic field also promoted hypoxia inducible factor-1αexpression in non-ischemia limb, but did not promote vascular endothelial growth factor and CD34 expression. Thus, the expression of vascular endothelial growth factor and CD34 was regulated by hypoxia inducible factor-1α, as wel as other factors, in the ischemic state.