MicroRNA-27b expression in rats submitted to physical exercise and experimental cerebral ischemia / Expresión de MicroRNA-27b en ratas sometidas a ejercicio físico e isquemia cerebral experimental

SUMMARY: Cerebral ischemia has not only a high mortality rate, which is the second leading cause of death worldwide, but is also responsible for severe disabilities in working age individuals, generating enormous public expending for treatment and rehabilitation of the affected individuals. The role of microRNAs in the pathophysiology of cerebral ischemia has been highlighted in current investigations. In addition, recent studies have also highlighted physical exercise as a possible protective factor both in the prevention and in the effects of cerebral ischemia, placing it as an important study resource. Thus, we investigated the role of physical exercise in experimental cerebral ischemia associated with the expression of microRNA-27b. 16 animals were used, divided into four experimental groups: Control, Physical Exercise, Cerebral Ischemia and Cerebral Ischemia associated with Physical Exercise. The real-time PCR methodology was used to analyze the expression of microRNA-27b. Although there were no statistically significant differences in the expression of microRNA-27b between the groups studied, the increased expression of microRNA-27b in the Physical Exercise group indicates its neuroprotective role in the pathophysiology of cerebral ischemia.

RESUMEN: La isquemia cerebral no solo tiene una alta tasa de mortalidad y es la segunda causa principal de muerte en todo el mundo, sino también es la causa de enfermedades invalidantes en personas en edad laboral, lo que genera un gasto público enorme para el tratamiento y la rehabilitación de las personas afectadas. El papel de los microARN en la fisiopatología de la isquemia cerebral se ha destacado en las investigaciones actuales. Además, estudios recientes también han destacado el ejercicio físico como un posible factor protector tanto en la prevención como en los efectos de la isquemia cerebral, situándolo como un importante recurso de estudio. Por lo tanto, investigamos el papel del ejercicio físico en la isquemia cerebral experimental asociada con la expresión del microARN-27b. Se utilizaron 16 animales, divididos en cuatro grupos experimentales: Control, Ejercicio Físico, Isquemia Cerebral e Isquemia Cerebral asociada al Ejercicio Físico. Se utili- zó la metodología de PCR en tiempo real para analizar la expresión de microARN-27b. Aunque no se observaron diferencias estadísticamente significativas en la expresión de microARN-27b entre los grupos estudiados, la mayor expresión de microARN-27b en el grupo de Ejercicio Físico indica su papel neuroprotector en la fisiopatología de la isquemia cerebral.

Expression of AIF, PARP, and miRNAs MIR-145, MIR-210, and MIR-486 associated with apoptosis in the corpus cavernosum of rats subjected to chronic alcoholism model / Expresión de AIF, PARP y miRNAs MIR-145, MIR-210 y MIR-486 asociados con apoptosis en el cuerpo cavernoso de ratas sometidas a modelo de alcoholismo crónico

SUMMARY: Previous studies from our group described the consequences of using ethanol on penile erection. Nevertheless, the molecular mechanisms surrounding microRNAs, apoptosis process and their relationship with erectile dysfunction associated with alcohol consumption are still poorly understood. The objective of this analysis was to evaluate the mechanism of apoptosis by the expression of AIF and PARP, as well as their regulatory microRNAs: miR-145, miR-210 and miR-486, in the corpus cavernosum of rats submitted to a semivoluntary alcoholism model. For this study 24 Wistar rats were divided into two groups: control (C) and treated with 20 % ethanol (A) for seven weeks. The corpus cavernosum samples were prepared for immunohistochemical analysis of AIF and PARP protein expression, and microRNAs miR-145, miR-210, miR-486 gene expression in cavernous tissue was performed by real time PCR. The immunohistochemical analysis showed little nuclear positive labeling for the protein PARP and AIF in the corpus cavernosum of control and ethanol treated animals. After analysis of miR-145, -210 and -486 microRNA expression in the 12 animals studied, no results were found with significant statistical difference between the control and alcoholized groups. The expression of AIF and PARP and their regulatory microRNAs involved in apoptotic process (miR-145, miR-210 and miR-486) were not altered in the corpus cavernosum of rats submitted to semivoluntary alcoholism.

RESUMEN: Estudios previos de nuestro grupo describieron las consecuencias del uso de etanol en la erección del pene. Sin embargo, los mecanismos moleculares que rodean a los microARN, el proceso de apoptosis y su relación con la disfunción eréctil asociada con el consumo de alcohol aún no se conocen bien. El objetivo de este análisis fue evaluar el mecanismo de apoptosis mediante la expresión de AIF y PARP, así como sus microARN reguladores: miR-145, miR-210 y miR-486, en el cuerpo cavernoso de ratas sometidas a un modelo de alcoholismo semivoluntario. Se dividieron 24 ratas Wistar en dos grupos: control (C) grupo de ratas tratadas con etanol al 20 % (A) durante siete semanas. Las muestras del cuerpo cavernoso se prepararon para el análisis inmunohistoquímico de la expresión de la proteína AIF y PARP, y la expresión del gen microRNAs miR-145, miR-210, miR-486 en tejido cavernoso se realizó por PCR en tiempo real. El análisis inmunohistoquímico mostró escaso etiquetado nuclear positivo para la proteína PARP y AIF en el cuerpo cavernoso de los animales de control y tratados con etanol. Después del análisis de la expresión de microARN miR-145, -210 y -486 no se encontraron resultados con diferencias estadísticas significativas entre los grupos control y alcoholizados. La expresión de AIF y PARP y sus microARN reguladores involucrados en el proceso apoptótico (miR-145, miR-210 y miR-486) no se alteraron en el cuerpo cavernoso de las ratas sometidas a alcoholismo semivoluntario.

Effect of swimming training on nerve morphological recovery after compressive injury.

OBJECTIVE: This study aims to investigate morphological alterations caused by partial sciatic nerve ligation (PNL) and the efficacy of a moderate-intensity swimming training as therapeutic strategy for nerve regeneration. METHODS: A number of 30 male adult mice were equally divided in control, 14 days after PNL (PNL 14 days), 42 days after PNL (PNL 42 days), 70 days after PNL (PNL 70 days) and 5-week exercise training after 7 days post-lesion (PNL trained 35 days) groups. PNL trained 35 days group began with a 10-min session for 3 days and this time was gradually increased by 10 min every three sessions until the animals had swum for 50 min per session. Morphoquantitative analysis was carried out to assess nerve regeneration in each group. RESULTS: PNL 14 days group exhibited less degenerating signs than PNL 42 days group, where most post-lesion alterations were visualized. Nerve area and minimum diameter were significantly lower (p < 0.05) than control group. PNL 70 days group showed a greater degree of regenerating fibers and similar morphometric parameters to control group. PNL trained 35 days demonstrated signs of regeneration, reaching control group values in the morphometric analysis. DISCUSSION: PNL promotes great histopathological changes, which became more visible at 42 post-injury days. A natural nerve-regeneration tendency was observed throughout time, as observed in PNL 70 days group; nevertheless, moderate swimming training was found to be a therapeutic resource for nerve regeneration, accelerating such process from a morphoquantitative perspective. ABBREVIATIONS: ANOVA: One-way analysis of variance; BDNF: Brain-derived neurotrophic factor; FGF-2: Fibroblast growth factor 2; GDNF: Glial cell line derived neurotrophic factor; IGF: Insulin-link growth factor; IL-1ß: Interleukin-1ß; NGF: Neural growth factor; PBS: Phosphate-buffered saline; PNL: Partial sciatic nerve ligation.

Apoptosis in bone defect of diabetic rats treated with low intensity laser: radiological and immunohistochemical approach / Apoptosis en ratones diabéticos con defecto oseo tratados con láser de baja intensidad: evaluación radiológica e inmunohistoquímica

The aim of this study is evaluate the efficacy of 904 nm laser diode in bone regeneration in the bone defect in diabetic rats. Six groups of 10 male Wistar rats and 2 mm bone defects drilled on the left and right tibia were used. The diabetic animals were treated with streptozotocin (40 mg/kg, i.v.). We compared the diode laser doses of treatment of bone defects 50 w ­ 4 J/cm and 100 w ­ 4J/. The right tibia was used for immunohistochemical analysis with the apoptosis markers XIAP and Caspase-3 and the left tibia was submitted to computer tomography (CT). Caspase-3 marker showed greater amount of apoptosis in all the untreated groups compared to both laser treatments. There was no statistical significance for XIAP marker. CT scan showed improvement of bone defect area and volume in both laser treated groups, control and diabetic. Therefore the low intensity laser therapy was effective in accelerating bone repair in both, control and diabetic groups. It was evidenced in our study that diabetes influences bone repair negatively.

Los objetivos de este estudio fueron evaluar la eficacia del láser diodo de 904 nm en la regeneración ósea del defecto óseo en ratas diabéticas. Se utilizaron seis grupos de 10 ratas Wistar macho y se generó un defecto óseo de 2 mm en las tibias izquierda y derecha de los animales. El animal diabético fue generado con estreptozotocina (40 mg / kg, i.v.). Se compararon las dosis de tratamiento de los defectos óseos con láser de diodo de 50 w - 4 J / cm y 100w - 4 J /. La tibia derecha fue utilizada para el análisis inmunohistoquímico con los marcadores de apoptosis XIAP y Caspasa-3 y la tibia izquierda fue sometida a tomografía computarizada. El marcador caspasa-3 mostró mayor cantidad de apoptosis en todos los grupos no tratados en comparación con ambos tratamientos con láser. No hubo significación estadística para el marcador XIAP. La tomografía computarizada mostró una mejoría del área y el volumen de los defectos óseos en ambos grupos tratados con láser, control y diabéticos. Por lo tanto, la terapia con láser de baja intensidad fue eficaz en la aceleración de la reparación ósea tanto en los grupos control como en los diabéticos. Se evidenció en nuestro estudio que la diabetes afecta negativamente la reparación ósea.

Development of a multifunctional needle for percutaneous heart biopsy and cell therapy. a technical note

Abstract Validation of transendocardial injection as a method for delivering therapeutic agents to the diseased heart is increasing. Puncture heart biopsies should re-emerge as a possible alternative method to allow access to the myocardium and implantable biomaterial for cell therapy. Therefore, this work aims to present a percutaneous puncture device for biopsy and intramyocardial biomaterial injection, standardize the technique and attest to the safety of the method. The adaptation consists of creating myocardial microlesions that allow for better fixation of stem cells. The objective of this technical note covers only the development of the needle and the histological quality of the biopsies. It has not been used in humans yet.

Development of a Multifunctional Needle for Percutaneous Heart Biopsy and Cell Therapy. A Technical Note.

Validation of transendocardial injection as a method for delivering therapeutic agents to the diseased heart is increasing. Puncture heart biopsies should re-emerge as a possible alternative method to allow access to the myocardium and implantable biomaterial for cell therapy. Therefore, this work aims to present a percutaneous puncture device for biopsy and intramyocardial biomaterial injection, standardize the technique and attest to the safety of the method. The adaptation consists of creating myocardial microlesions that allow for better fixation of stem cells. The objective of this technical note covers only the development of the needle and the histological quality of the biopsies. It has not been used in humans yet.

Bone integration behavior of hydroxyapatite/ß-tricalcium phosphate graft implanted in dental alveoli: a histomorphometric and scanning electron microscopy study.

PURPOSE: This study investigated the bone integration ability of a biphasic calcium phosphate bioceramic implanted in dental alveolus of rats. MATERIALS AND METHODS: A total of 21 male rats were submitted to upper right incisor extraction and implanted with a synthetic bioceramic (Straumann Bone Ceramic). The animals were killed on 7th, 21st, and 42nd day after surgery for light and scanning electron microscopy (SEM) analysis of bone, bioceramic, and soft tissue volume as well as the quality of graft in its interface. RESULTS: Light histology results showed no persistent inflammatory and foreign body reactions, a newly formed bone adhered on the ceramic surface without interposition of soft tissue, which was confirmed by SEM analysis. Histometrically, reduction/resorption, between 7 and 42 days, in the percentage of bioceramic implanted (α = 1%) left gaps for a gradual increase in vital bone formation (α = 1%) around the particles. CONCLUSIONS: The bioceramic in question is biocompatible, has good bone integration, being gradually resorbed and replaced by it, featuring a viable bone substitute for grafting procedures.

Low-level laser therapy on the viability of skin flap in rats subjected to deleterious effect of nicotine.

OBJECTIVE: The purpose of this study was to evaluate the effect of 830-nm laser in blocking the action of nicotine on the viability of skin flap. BACKGROUND DATA: The authors have analyzed the deleterious effect of cigarette smoke or nicotine on the skin flap alone with evidence of increased skin necrosis in the flap. MATERIALS AND METHODS: Twenty-four Wistar-albino rats were divided into three groups of eight animals each: Group 1 (control), subjected to a surgical technique to obtain a flap for cranial base, laser irradiation simulation, and a subcutaneous injection of saline; Group 2, similar to Group 1, with subcutaneous injection of nicotine (2 mg/kg/day) for a period of 1 week before and 1 week after surgery; and Group 3, similar to Group 2, with skin flaps subjected to a λ 830-nm laser irradiation. The laser parameters used were: power 30 mW, beam area 0.07 cm(2), irradiance 429 mW/cm(2), irradiation time 84 sec, total energy 2.52 J, and energy density 36 J/cm(2). The laser was used immediately after surgery and for 4 consecutive days, in one point at 2.5 cm of the flap cranial base. The areas of necrosis were examined by two macroscopic analyses: paper template and Mini-Mop(®). The pervious blood vessels were also counted. RESULTS: The results were statistically analyzed by ANOVA and post-test contrast orthogonal method (multiple comparisons), showing that the laser decreased the area of necrosis in flaps subjected to nicotine, and consequently, increased the number of blood vessels (p < 0.05). CONCLUSIONS: The laser proved to be an effective way to decrease the area of necrosis in rats subjected to nicotine, making them similar to the control group.

Laser 830nm na viabilidade do retalho cutâneo de ratos submetidos à nicotina / Laser 830nm on the viability of skin flaps in rats submitted of nicotine

OBJETIVO: Investigar os possíveis efeitos da laserterapia com laser diodo 830nm ao se contrapor a ação da nicotina na viabilidade do retalho cutâneo em ratos. MÉTODOS: Foram utilizados 16 ratos Wistar, distribuídos em 2 grupos de 8: Grupo 1- submetido à técnica cirúrgica, para obtenção dos retalhos cutâneos randômicos de base cranial, com injeção subcutânea de nicotina em uma dose de 2mg/Kg/dia, uma semana antes e uma semana após o procedimento cirúrgico e simulação da radiação laser; Grupo 2- similar ao grupo 1, cujos retalhos cutâneos randômicos de base cranial foram submetidos à irradiação do laser imediatamente após a cirurgia e nos 4 dias subsequentes. Após a eutanásia, as áreas de necrose e de tecido viável foram examinadas através do método de pesagem do Gabarito de Papel e pelo método semi-automático de análise de imagens (Mini-Mop®). RESULTADOS: Os resultados foram analisados estatisticamente através do teste ANOVA. Os valores de porcentagem de área de necrose através do método de análise mostraram uma diminuição da área de necrose no grupo 2 onde foi aplicado laser. CONCLUSÃO: O laser 830nm foi eficaz na melhora da viabilidade do retalho cutâneo em ratos submetido à ação da nicotina. Nível de evidência II: Estudos terapêuticos - Investigação dos resultados do tratamento.

OBJECTIVE: To investigate the possible effects of laser diode 830nm counter to the action of nicotine on the viability of the skin flap in rats. METHODS: 24 Wistar-albino rats were used, divided into 3 groups of 8: Group 1 - subject to the surgical technique to obtain the random skin flap in cranial base, subcutaneous injection of nicotine of 2mg/Kg/dia a week before and one week after surgery and simulation of laser. Group 2 - similar to group 1, the random skin flap in the cranial base were subjected to laser irradiation immediately after surgery and on thesubsequent 4 days. After euthanasia, areas of necrosis and viable tissue were examined by a manual method (weighing the Role of Feedback) and by the semi-automated method of analysis (Mini-Mop®). RESULTS: The results were statistically analyzed by ANOVA. The values of the percentage of necrotic area by the method of analysis showed a decreased area of necrosis in group 2 where the laser was applied. CONCLUSION: The 830nm laser was effective in improving the viability of skin flaps in rats subjected to the action of nicotine. Level of evidence II: Therapeutic Studies - Investigating the results of treatment.

A simple and efficient device for demonstrating cross-sectional anatomy of the head.

Described in this article is a novel device that facilitates study of the cross-sectional anatomy of the human head. In designing our device, we aimed to protect sections of the head from the destructive action of handling during anatomy laboratory while also ensuring excellent visualization of the anatomic structures. We used an electric saw to create 15-mm sections of three cadaver heads in the three traditional anatomic planes and inserted each section into a thin, perforated display box made of transparent acrylic material. The thin display boxes with head sections are kept in anatomical order in a larger transparent acrylic storage box containing formaldehyde solution, which preserves the specimens but also permits direct observation of the structures and their anatomic relationships to each other. This box-within-box design allows students to easily view sections of a head in its anatomical position as well as to examine internal structures by manipulating individual display boxes without altering the integrity of the preparations. This methodology for demonstrating cross-section anatomy allows efficient use of cadaveric material and technician time while also giving learners the best possible handling and visualization of complex anatomic structures. Our approach to teaching cross-sectional anatomy of the head can be applied to any part of human body, and the value of our device design will only increase as more complicated understandings of cross-sectional anatomy are required by advances and proliferation of imaging technology.

Estudo microscópico da interface implante-osso vertebral e sua relação com o modo de preparo do orifício piloto / Estudio microscópico de la interface implante hueso vertebral y su relación con el modo de preparación del orificio piloto / Microscopical study of the bone screw interface and its correlation with the pilot hole preparation

OBJETIVO: estudar as alterações do tecido ósseo da interface entre o implante e o osso da vértebra submetido ao preparo do orifício piloto por meio de sonda, broca e broca seguida de macheamento. MÉTODOS: foram utilizadas três vértebras lombares (l2-L3-L4) de cadáveres humanos adultos do sexo masculino. No interior dos pedículos vertebrais, foram inseridos parafusos de 6 mm de diâmetro externo do sistema USIS de fixação vertebral. O preparo do orifício piloto para a inserção dos parafusos nos pedículos vertebrais foi realizado por meio de sonda, broca ou broca seguida de macheamento. As vértebras foram preparadas para o estudo em microscopia de luz e foi avaliado o coeficiente de fragmentação por meio da relação entre a porcentagem da área ocupada por tecido ósseo na região próxima do implante e no osso normal. RESULTADOS: o coeficiente de fragmentação foi menor, com diferença estatística, no grupo do orifício piloto preparado com sonda em relação ao orifício piloto preparado com broca ou broca seguida de macheamento. CONCLUSÃO: o menor coeficiente de fragmentação observado com a utilização da sonda para a realização do orifício piloto indica a maior compactação do osso na interface entre o implante e o osso da vértebra

OBJECTIVE: to access microscopically bone tissue changes between vertebral bone and implant interface, whose pilot hole was prepared using probe, drill and drill followed by tapping. METHODS: the vertebral pedicles of three segments (L2-L3-L4) of human adult cadaver lumbar spine were instrumented with 6 mm USIS pedicle screw. The pilot holes for screw insertion into pedicles were prepared using probe, drill and drill followed by tapping. The vertebrae were prepared to histological study on light microscopy and the fragmentation index assessed by percentage relation between bone tissue close to the implant and normal bone. RESULTS: the fragmentation index of pilot holes prepared with probes was statistically lower than those prepared with drill and drill followed by tapping. CONCLUSION: the low fragmentation index observed that the use of probe to perform pilot hole promotes higher compaction of bone between the screw and vertebral bone interface.

OBJETIVO: estudiar las alteraciones del tejido óseo de la interfase entre el implante y el hueso de la vértebra, sometido al preparo del orificio piloto por medio de sonda, broca y broca seguida de aplastamiento. MÉTODOS: fueron utilizadas tres vértebras lumbares (L2-L3-L4) de cadáveres humanos adultos del sexo masculino. En el interior de los pedículos vertebrales fueron insertados tornillos de 6 mm de diámetro externo del sistema USIS de fijación vertebral. El preparo del orificio piloto, para la inserción de los tornillos en los pedículos vertebrales, fue realizado por medio de sonda, broca o broca seguida de aplastamiento. Las vértebras fueron preparadas para el estudio en microscopio de luz y fue evaluado el coeficiente de fragmentación por medio de la relación entre el porcentaje del área ocupada por el tejido óseo en la región próxima del implante y en el hueso normal. RESULTADOS: el coeficiente de fragmentación fue menor con diferencia estadística en el grupo del orificio piloto preparado con sonda, cuando comparado con el orificio piloto preparado con broca o broca seguida de aplastamiento. CONCLUSIÓN: el menor coeficiente de fragmentación observado con la utilización de la sonda para la realización del orificio piloto indica la mayor compactación del hueso, en la interface entre el implante y el hueso de la vértebra.

Efeitos do processamento químico e da esterilização em Óxido de etileno em osso cortical e esponjoso de ratas: estudo com microscopia de luz e eletrônica de varredura / Effects of chemical processing and oxide ethylene sterilization on cortical and cancellous rat bone: a light and electron scanning microscopy study

OBJETIVO: Avaliar, sob o ponto de vista microscópico, modificações estruturais do osso esponjoso e cortical, após serem submetidos a processamento químico e esterilização em óxido de etileno. MÉTODOS: Amostras de osso esponjoso e cortical foram obtidas de fêmures de ratas albinas jovens (Wistar)e separadas em quatro grupos contendo osso cortical e esponjoso: I- Fragmentos secos em estufa; II- Fragmentos secos em estufa e esterilizados em óxido de etileno; III- Fragmentos processados quimicamente; IV- Fragmentos processados quimicamente e esterilizados em óxido de etileno. Metade desse material foi analisada em microscópio eletrônico de varredura e, a outra metade, em microscopia de luz convencional. RESULTADOS: Houve preservação da morfologia geral das amostras em todos os grupos. Nos grupos submetidos ao processamento químico houve melhor preservação do conteúdo celular, enquanto que naqueles submetido ao óxido de etileno houve amalgamação fibrilar. CONCLUSÃO: O tratamento com óxido de etileno causou amalgamação das fibrilas possivelmente em decorrência do efeito do calor e o tratamento químico contribuiu para melhor preservação da estrutura óssea.

OBJECTIVE: To evaluate, under microscopic examination, the structural changes displayed by the trabecular and cortical bones after being processed chemically and sterilized by ethylene oxide. METHODS: Samples of cancellous and cortical bones obtained from young female albinus rats (Wistar) were assigned to four groups according to the type of treatment: Group I-drying; Group II-drying and ethylene oxide sterilization; III-chemical treatment; IV-chemical treatment and ethylene oxide sterilization. Half of this material was analyzed under ordinary light microscope and the other half using scanning electron microscopy. RESULTS: In all the samples, regardless the group, there was good preservation of the general morphology. For samples submitted to the chemical processing there was better preservation of the cellular content, whereas there was amalgamation of the fibres when ethylene oxide was used. CONCLUSION: Treatment with ethylene oxide caused amalgamation of the fibers, possibly because of heating and the chemical treatment contributed to a better cellular preservation of the osseous structure.

Can therapeutic ultrasound influence the integration of skin grafts?

Therapeutic ultrasound (TUS) is a widely used coadjuvant physical means to promote biological tissue repair. In the present investigation, the influence of TUS on the integration of full-thickness skin graft was studied in rabbits. Twenty female adult rabbits were used and two 2x2-cm square full-thickness skin grafts were obtained from both scapular regions and swapped, the one cut out on the right being placed on the left and vice versa. The graft on the right was irradiated with TUS (3 MHz, 0.5 W/cm2, 5-min duration) once a day for seven consecutive days, beginning on the third postoperative day; the graft on the left was submitted to simulated irradiation. The animals were killed on the 11th day and the grafted areas were resected (graft+safety margin) for histological examination. Five-mum-thick sections were alternatively stained with Gomori's trichrome, proliferating cell nuclear antigen (PCNA) and picrosirius red and examined under the light microscope, and the epidermal and dermal areas were measured and proliferating cells and new blood vessels counted. The results showed a significant increase (p=0.007) in the number of proliferating epidermal cells (12.18% and 7.34% of the total number of cells in the irradiated and control grafts, respectively) and new blood vessels per field (p=0.0001) in the irradiated grafts (6.27 compared with 3.07). Despite the increased number of proliferating cells and blood vessels, there was no significant difference between the epidermis (246,392 microm2 and 200,626 microm2 in groups 1 and 2, respectively; p=0.07) and dermis (2,157,730 microm2 and 2,109,150 microm2 in groups 1 and 2, respectively; p=0.21) areas as a function of thickness for both groups. We conclude that TUS induces morphological alterations in biological processes, such as epidermic germinative layer cell proliferation and neoangiogenesis, which are involved in the integration of full-thickness skin grafts. This has a potential for clinical use in humans.

Prótese vascular derivada do látex / Latex-derived vascular prosthesis

CONTEXTO: O desenvolvimento de prótese vascular tem sido vital para os avanços e realizações da cirurgia vascular reconstrutora durante as últimas 5 décadas. OBJETIVOS: Desenvolver um novo modelo de prótese vascular microperfurada, confeccionada em tecido recoberto com um composto derivado do látex natural da seringueira (Hevea brasiliensis) e avaliar sua perviedade, trombogenicidade, biocompatibilidade e o processo de cicatrização, além de algumas propriedades mecânicas (adaptabilidade, elasticidade, impermeabilidade e possibilidade de sutura), utilizando como controle a prótese de politetrafluoretileno expandido no mesmo animal. MÉTODOS: Quinze cães foram separados em três grupos de cinco animais. Implantou-se a prótese de tecido e látex microperfurada e, no membro pélvico contralateral, a prótese de politetrafluoretileno expandido em todos os cães. O seguimento pós-operatório foi de 4, 8 e 12 semanas. A apreciação dos resultados foi feita segundo as avaliações clínicas dos pulsos, complicações (coleção líquida, deiscência, granuloma e infecção), arteriografias, análise macroscópica e elétron-micrografias de varredura. RESULTADOS: Os testes estatísticos aplicados não evidenciaram diferenças significativas (p > 0,05) em relação às complicações pós-operatórias e perviedade dos enxertos. Ambas as próteses integraram-se adequadamente aos tecidos circunvizinhos, com um tecido de incorporação formado por fibras colágenas. Constatou-se a presença de neoíntima recoberta por endotélio em toda a extensão da superfície luminal da prótese de tecido e látex microperfurada. Ao contrário, na prótese de politetrafluoretileno expandido, o desenvolvimento endotelial sobre a superfície neointimal limitou-se às regiões próximas às anastomoses. CONCLUSÕES: A prótese de tecido e látex microperfurada demonstrou qualidades estruturais (adaptabilidade, elasticidade, impermeabilidade e possibilidade de sutura) satisfatórias como substituto vascular. Estimulou...

BACKGROUND: The development of vascular grafts has been crucial for advances and achievements in reconstructive vascular surgery over the past 5 decades. OBJECTIVES: To develop a new model of microperforated vascular graft using fabric covered with a natural latex-derived polymer taken from Hevea brasiliensis and assess its patency, thrombogenicity, biocompatibility and healing process, besides some mechanical properties (adaptability, elasticity, impermeability and possibility of suture), using expanded polytetrafluoroethylene graft as control. METHODS: Fifteen dogs were divided into three groups of five animals. The microperforated latex graft was implanted in all dogs and the expanded polytetrafluoroethylene graft was implanted in the contralateral pelvic limb. Postoperative follow-up was 4, 8 and 12 weeks. Analysis of results was performed according to clinical evaluation of pulses, complications (fluid collection, dehiscence, granuloma and infection), arteriography, macroscopic analysis and scanning electron micrography. RESULTS: Statistical tests revealed no significant differences (p > 0.05) concerning post-operative complications and graft patency. Both grafts were properly integrated to surrounding tissues, with connective tissue formed by collagen fibers. A neointimal layer covering all extension of the luminal surface was observed in the microperforated latex graft. Conversely, the endothelial development over the neointimal surface was limited to regions adjacent to the anastomoses in the expanded polytetrafluoroethylene graft. CONCLUSIONS: The microperforated latex graft showed satisfactory structural qualities (adaptability, elasticity, impermeability and possibility of suture) as a vascular substitute. It stimulated endothelial growth beyond contact regions with the artery in anastomoses and was biocompatible in the dog's arterial system, presenting adequate tissue integration.

Efeitos do processamento químico, da esterilização em óxido de etileno e da usinagem em parafusos de osso bovino: estudo com microscopia eletrônica de varredura / Effects of chemical processing, oxide ethylene sterilization, and machining on screw made of bovine bone: a scanning by electron microscopy study

Objetivo: Avaliar a influência do processo de preparação química, esterilização em óxido de etileno e usinagem sobre a microestrutura da superfície óssea visando a estudos futuros para confecção de parafusos ósseos. Métodos: A partir de osso obtido do córtex externo de tíbias bovinas foram obtidas amostras em formato de cubos e confeccionados parafusos, com o uso de técnicas de mecânica de precisão. Metade desse material foi conservada sob refrigeração e, a outra metade, processada quimicamente, com fixação em álcool etílico, clareamento em água oxigenada, desengorduramento em éter etílico, secagem em estufa e esterilização em óxido de etileno. A repercussão desse tratamento sobre a estrutura óssea foi avaliada por microscopia eletrônica de varredura realizada em todas as amostras. A comparação foi com os corpos do mesmo material e formato, mas apenas mantidos refrigerados. Resultados: Observou-se que a esterilização e o processamento químico utilizado causaram amalgamação da estrutura fibrilar da superfície óssea, apenas notada em grande aumento, tanto nos cubos ósseos, quanto nos parafusos. Com relação à usinagem, as ranhuras causadas pela instrumentação eram mais nítidas nos parafusos de osso in natura, mas as microfraturas existentes foram qualitativamente iguais nos dois grupos. As roscas dos parafusos apresentaram irregularidades e microfraturas, tanto nos parafusos tratados quanto nos não tratados. Conclusão: O tratamento químico usado e a esterilização em óxido de etileno causaram alterações de amalgamação na superfície do osso e a usinagem provocou microfraturas, tanto nos parafusos processados quanto nos não processados. As ranhuras causadas pela ferramenta de usinagem foram mais nítidas nas amostras in natura dos parafusos. A repercussão desses achados sobre o desempenho mecânico dos parafusos necessita investigações futuras...

Transdermal delivery of ketoprofen: the influence of drug-dioleylphosphatidylcholine interactions.

PURPOSE: Considering that most inflammatory diseases occur locally and near the body surface, transdermal delivery of non-steroidal anti-inflammatory drugs (NSAIDs) may be an interesting strategy for delivering these drugs directly to the diseased site. To optimize ketoprofen (KP) transdermal delivery we investigated the influence of dioleylphosphatidylcholine (DOPC) on skin permeation. MATERIALS AND METHODS: The formulations studied were: i) a physical mixture of KP and DOPC and ii) DOPC and KP complex, in a molar ratio of 1:3, obtained by dissolution of the components in chloroform followed by drying under a N2 atmosphere. Both systems were dispersed in mineral oil and the in vitro percutaneous was assayed by absorption using a flow through diffusion cell. Differential Scanning Calorimetry (DSC) and 1H NMR studies were carried out to characterize KP and DOPC interactions. Geometry optimizations using Density Functional Theory and semiempirical methods, as well as a flexible docking procedure were carried out to obtain a binding model for KP with DOPC. KP solubility and partition studies in the formulations, as well as skin irritation and hypersensitivity assays were also carried out. RESULTS: DSC determinations in the complex showed enthalpy and temperature depressions, indicating KP and DOPC interaction. In addition, dipole-dipole interactions between the KP carboxylic acid and OH groups in phospholipids were shown by 1H NMR studies. Based on the NMR studies, a KP-DOPC binding model is proposed, in which KP is involved by the two long aliphatic chains of the phospholipid. Solubility studies indicated that DOPC improved drug solubility. KP permeation was enhanced by both formulations tested, but the complex also increased its skin uptake. Such behavior could be attributed to the solubilizing, melting and enhancing effects of DOPC. Skin irritation and hypersensitivity were not significantly changed compared to control, suggesting that the formulation may be therapeutically explored for KP transdermal delivery.

Estimulação ultra-sônica da integração de enxertos de pele total: estudo experimental em coelhos

Foi realizado um estudo histológico experimental da influência do ultra-som terapêutico na integração de enxertos de pele de espessura total em 20 coelhas adultas. Dois enxertos quadrados de 2 cm de lado foram obtidos nas regiões escapulares e trocados de lado. O enxerto à direita foi irradiado diariamente (3 MHz, 0,5 W/cm2, duração 5 minutos) desde o terceiro dia e por sete dias consecutivos; à esquerda, o tratamento era simulado. O estudo histológico em cortes de 5 æm de espessura obtidos de cada enxerto e corados alternativamente com o tricrômico de Gomori, PCNA e picrosírius, incluiu a medida das áreas da epiderme e da derme, a contagem das células em proliferação na camada germinativa e os vasos neoformados e a orientação das fibras colágenas. Foi observado aumento significante do número de células proliferativas (p=0,007) e dos vasos neoformados (p=0,0001) nos enxertos irradiados, mas não na área da epiderme e da derme. Os autores concluíram que o UST induz alterações morfológicas nos processos biológicos envolvidos na integração do enxerto de pele de espessura total, como a proliferação das células germinativas e a formação de novos vasos sangüíneos, e sugerem que há potencial para o uso clínico em humanos.

An experimental histological study was performed addressing the influence of therapeutic ultrasound on total-thickness skin grafts union in 20 adult female rabbits. Two 2-cm square-shaped grafts, were obtained at scapular regions with sides switched. The graft at right was irradiated on a daily basis (3 MHz, 0.5 W/cm2, for 5 minutes) from the third day on, during seven consecutive days; the graft at left received a sham treatment. The histological study in 5 æm-thick slides obtained from each graft and alternatively stained with Gomori trichromic, PCNA and picrosirius, included measurement of epidermal and dermal areas, proliferating cells on germinative layer counts, and neoformed vessels and collagen fibers direction. A significant increase of the number of proliferating cells (p=0.007) and of neoformed vessels (p=0.0001) was noticed on irradiated grafts, but not on epidermal and dermal areas. The authors concluded that the T-U/S induces morphological changes in biological processes involved on total-thickness skin graft union, such as germinative cells proliferation and new blood vessels formation, suggesting the potential for its clinical use in human beings.

Alcohol intake and osseointegration around implants: a histometric and scanning electron microscopy study.

Alveolar wound healing can be modified by local and systemic factors. The aim of this study was to evaluate the possible effect of alcoholic beverage administration (sugarcane brandy) on reparative bone formation around hydroxyapatite/tricalcium phosphate implants inside the alveolar socket. Male Wistar rats had their upper right incisors extracted and the bioceramic granules implanted in the alveoli. The animals received increasing concentrations of brandy until 30 degrees Gay-Lussac was achieved starting 30 days before dental extraction and maintained for periods varying from 1 hour to 6 weeks, until sacrifice. Blood alcohol concentration analysis was performed as well as histological and histometric analysis through light and scanning electron microscopy to examine the relation between alveolar healing components, including new bone trabeculae, and the implants. Blood alcohol concentration was significantly higher in treated animals compared with controls. A significant delay in reparative bone formation was detected in the alveolus of alcoholic rats by a histometric differential point counting method, whereas the presence of the bioceramic in the alveolar socket improved alveolar wound healing in alcohol-treated rats. It is suggested that the osteoconductive properties of this bioceramic accelerated alveolar wound healing in alcoholic rats.