RESUMO: As afecções ortopédicas com perda de tecido ósseo são um desafio não só na medicina veterinária mas também na medicina humana. Analisou a interface entre compósito, constituído de esferas de quitosana e polimetilmetacrilato em falha óssea (leito receptor) de tíbia de coelhos, por meio de técnica radiológica, avaliação macroscópica e pela microscopia eletrônica de varredura, em diferentes tempos. Foram utilizados 12 coelhos adultos da raça Nova Zelândia, divididos em quatro Grupos Experimentais (E1, n=3; E2, n=3; E3, n=3 e E4, n=3), que tiveram as falhas ósseas das tibiais direitas preenchidas com compósito, e avaliadas no pós-operatório imediato, aos 30, 60 e 90 e 120 dias. Dos compósitos implantados nas tíbias de coelhos, apenas dois permaneceram em seus leitos receptores, enquanto que os demais se encontravam encapsulados no tecido subcutâneo. As esferas de quitosana, presentes nas superfícies dos biomateriais implantados, que mantiveram contato direto com o leito receptor de tíbias de coelhos apresentavam-se preservadas e não integraram ao tecido ósseo. Diante disso, para melhor compreensão do comportamento da quitosana como substituto ósseo, novas pesquisas serão necessárias.

ABSTRACT: Orthopedic diseases with bone loss are challenging in both veterinary and human medicine. The aim of this investigation was to analyze and compare the reactions at the interface between the composite, made of chitosan and polymethylmethacrylate, and the bone defect (receptor site) of the rabbits tibia through radiological and microscopic techniques and by scanning electron microscopy, in different periods. Twelve adult New Zealand rabbits were divided into four experimental groups (E1, n=3; E2, n=3; E3, n=3 and E4, n=3), which had the right tibial bone defects filled with the composite, and evaluated in the immediate postoperative, 30, 60, 90 and 120 days. Composite implanted in the tibia of rabbits, only two remained in their beds receivers, while the remaining were encapsulated in the subcutaneous tissue. Spheres of chitosan present in the biomaterial that has been deployed and were in direct contact with the bone defect, were preserved, however, were not integrated into the bone tissue. Therefore, to understand the behavior of chitosan as a bone substitute, further research is needed.

ABSTRACT The objective of this study was to evaluate the testicular echotexture of Nelore bulls and to correlate it with spermatogenic parameters. Forty one bulls aged 3-5 years, with body weight of 510.2 ± 21.61 kg were selected for the study. The animals were subjected to ultrasonography, using a portable device coupled with a linear transducer at a frequency of 7.5 MHz. Immediately afterwards they were castrated and the testicular tissue was treated with Karnovsky fixative. Next, the fragments were embedded in glycol methacrylate and stained with toluidine blue-1% sodium borate solution. The average pixel intensity in the testicular parenchyma was determined for 1,600-mm2 surface sections. The right and left testicles and the area between the two testicles resulted in average pixel intensities of 105.22 ± 13.58, 107.95 ± 12.82, and 106.59 ± 11.43, respectively. The efficiency coefficient of spermatogonial mitosis was 19.74; meiotic index was 2.63, and overall yield of spermatogenesis was 52.0. No correlation (P>0.05) was observed between testicular echotexture and any of the measured morphometric parameters. These results suggest that testicular echotexture was not a viable method for the indirect analysis of cellular population in the seminiferous epithelium, intrinsic spermatogenic performance, or the Sertoli cell index in Nelore bulls.

RESUMEN El objetivo de este estudio fue evaluar la ecotextura testicular de los toros Nelore y correlacionarlo con los parámetros de espermatogénesis. Para este propósito, 41 toros de edades de 3-5 años y con pesos corporales en el intervalo de 510,2 ± 21,61 kg fueron seleccionados para el estudio. Los toros se sometieron a ecografía, utilizando un dispositivo portátil junto con un transductor lineal a una frecuencia de 7,5 MHz. Inmediatamente después, los animales fueron castrados, y el tejido testicular se trató con Karnovsky fijador. Los fragmentos testiculares se incluyeron en metacrilato de glicol y se tiñeron con una solución de borato de sodio-azul de toluidina al 1%. La intensidad media de pixeles en el parénquima testicular se determinó para secciones de superficie de 1.600 mm2. Los El área entre los dos testículos derecho e izquierdo dieron lugar a la intensidad media de los pixeles de 105,22 ± 13,58, 107,95 ± 12,82 y 106,59 ± 11,43, respectivamente. El coeficiente de eficiencia de la mitosis espermatogonial fue 19,74; Índice meiótico fue 2,63, y el rendimiento global del espermatogénesis alcanzó el 52,0. No se observó correlación (P>0,05) entre ecotextura testicular y cualquiera de los parámetros morfométricos medidos. Estos resultados sugieren que ecotextura testicular no es un método viable para el análisis indirecto de la población celular en el epitelio seminífero, el rendimiento de la espermatogénesis intrínseco, o el índice de células de Sertoli en toros Nelore.

O objetivo deste estudo foi avaliar o efeito preventivo do bicarbonato de sódio sobre a acidose sistêmica em decorrência da acidose ruminal, a qual foi induzida pelo fornecimento de concentrado após jejum prolongado. Foram utilizados 14 ovinos, divididos em três grupos experimentais: grupo controle (Cg), contendo quatro ovinos, submetidos a jejum sem desenvolvimento de acidose ruminal; grupo não tratado (NTg), contendo cinco ovinos submetidos a acidose ruminal sem tratamento preventivo; e grupo tratado (Tg), contendo cinco ovinos, submetidos a acidose ruminal e tratados preventivamente com bicarbonato de sódio. Foram realizadas avaliações do pH ruminal e hemogasometria arterial, durante 48 horas após o fornecimento do concentrado. Houve redução do pH ruminal em todos os grupos, sendo que o Cg apresentou a redução apenas às 24 horas. Notou-se redução do pH arterial, bicarbonato e excesso de base em todos os grupos, indicando acidose metabólica sistêmica; no entanto, o NTg apresentou o quadro mais grave. Conclui-se que o bicarbonato de sódio possui efeito preventivo da acidose metabólica sistêmica, reduzindo a sua gravidade em ovinos submetidos à acidose ruminal.

The aim of this study was to evaluate the preventive effect of sodium bicarbonate on systemic acidosis due to ruminal acidosis, which was induced by ingestion of concentrate after prolonged fasting. Fourteen sheep were divided into three experimental groups: control group (Cg), with four sheep, submitted to fasting without development of ruminal acidosis; no-treated group (NTg), with five sheep with rumen acidosis without preventive treatment; and treated group (Tg), with five sheep with rumen acidosis and preventively treated with sodium bicarbonate. Assessments of ruminal pH and arterial hemogasometry were performed for 48 hours after ingestion of the concentrate. There was a reduction in the ruminal pH in all groups, whereas the Cg showed a reduction only after 24 hours. A reduction in the arterial pH, bicarbonate and base excess in all groups was also noted, indicating systemic metabolic acidosis, but the NTg presented the greatest alteration. It is concluded that sodium bicarbonate prevents systemic metabolic acidosis, reducing its severity in sheep subjected to ruminal acidosis.

Foi realizada falha segmentar com 6mm de diâmetro na região metafisária medial de tíbias de 12 coelhos, onde foi implantado uma associação de micro e macrofragmentos de matriz óssea cortical heteróloga fragmentada conservada em glicerina (98%) e polimetilmetacrilato autoclavados, para a sua reconstrução, e avaliados radiológica e macroscopicamente aos 30, 60, 90 e 120 dias. Houve adesão, em relação ao tempo, dos micro e macrocompósitos ao leito receptor, em 100% dos casos, mostrando ser biologicamente biocompatível, pois promoveram a reparação de falhas ósseas, sem sinais de infecção, migração e/ou rejeição, podendo, dessa forma, ser mais uma opção como substituto para preencher grandes defeitos ósseos.

A segmental defect of 6mm diameter was performed in the medial metaphyseal region of the tibia of 12 rabbits. For the bone defect reconstruction there was implanted a combination of micro and macro fragments of heterologous fragmented cortical bone matrix preserved in glycerin (98%) and polymethylmethacrylate, both autoclaved. Radiological and macroscopic evaluation was performed at 30, 60, 90 and 120 days. Adhesion in relation to time of the micro and macro composites to the recipient bed was observed in 100% of the cases. This showed that this implant is biologically biocompatible, since it promoted bone defects repair, with no signs of infection, migration and/or rejection. In this way, this implant can be classified as one more option of substitute to fill large bone defects.

Os traumas que resultam em fraturas ósseas, principalmente as cominutivas, têm uma importância muito grande na rotina clínico-cirúrgica veterinária e humana. Foi realizada falha segmentar de 6mm na região metafisária medial da tíbia esquerda de 12 coelhos, a qual foi preenchida com implante constituído de matriz óssea mineralizada heteróloga fragmentada e metilmetacrilato, preservados em glicerina (98%) para a sua reconstrução. Foi realizada avaliação morfológica e radiológica aos 30, 60, 90 e 120 dias e observou-se a incorporação do implante ao leito receptor, em 100% dos casos, mostrando ser biologicamente compatível, pois promoveu a reparação das falhas ósseas, sem sinais de infecção, migração e/ou rejeição, sendo uma opção de substituto para preencher defeitos ósseos.

The traumas that result in bone fractures, especially comminuted, have high importance in veterinary and human surgical routine. A 6mm of segmental defect was performed at the medial metaphyseal region of the left tibia of 12 rabbits and an association of fragmented heterologue mineralized bone matrix and methylmethacrylate conserved in glycerin (98%) was used as a graft to fill the bone defect. To evaluate the procedure morphological and radiological exams were performed after 30, 60, 90 and 120 days. There was gradual integration of the bone graft in the receptor bed in 100% of the cases showing that the material is biologically compatible as it promotes bone defect reparation without signs of infection, migration and/or rejection and can be considered one more option to be used as a substitute to fill bone defects.