Celso Massaschi Inouye

Isquemia e reperfusão de músculo sóleo de ratos sob ação da pentoxifilina

BACKGROUND: Reperfusion of the skeletal muscle worsens existing lesions during ischemia, since the production of reactive oxygen species, associated with intense participation of neutrophils, increases the inflammatory reaction that induces tissue changes. OBJECTIVE: To evaluate the morphological and immunohistochemical changes of the skeletal (soleus) muscle of rats submitted to ischemia and reperfusion with pentoxifylline. METHODS: Sixty rats were submitted to ischemia of the pelvic limb for 6 hours induced by clamping the left common iliac artery. After ischemia, group A animals (n = 30) were observed for 4 hours and group B animals (n = 30) for 24 hours. Six animals constituted the sham group. Pentoxifylline was applied only in the reperfusion period A2 (n = 10) and B2 (n = 10), and in ischemia and reperfusion periods in A3 (n = 10) and B3 (n = 10). The soleus muscle was evaluated by histological (fiber disruption, leukocyte infiltrate, necrosis) and immunohistochemical (apoptosis through caspase-3 expression) analysis. The non-parametric tests Kruskal-Wallis and Mann-Whitney (p < 0.05) were applied. RESULTS: The changes were more intense in group B1, with fiber disruption mean scores of 2.16±0.14; neutrophilic infiltrate of 2.05±0.10; and caspase-3 expression in the perivascular area of 4.30±0.79; and less intense in group A3, with means of 0.76±0.16; 0.92±0.10; 0.67±0,15, respectively (p < 0.05). Caspase-3 was more expressive in group B1 in the perivascular area, with mean of 4.30±0.79 when compared with group B1 in the perinuclear area, with mean of 0.91±0.32 (p < 0.05) CONCLUSIONS: The lesions were more intense when observation time was longer after reperfusion, and pentoxifylline attenuated these lesions, above all when used in the beginning of ischemia and reperfusion phases.

Efeito de dietas hiperlipídicas com extrato de baru e chocolate sobre a área de adipócitos de ratos submetidos ao exercício físico

INTRODUCTION: Fat tissue accumulation provokes several metabolic disorders, which may be attenuated by dietetic modulation and physical exercise. OBJECTIVE: The effects of hypercaloric/hyperlipidic diets with additional baru extract associated to aerobic exercise on adipocytes from different regions as well as on hepatic triglycerides (TGLhep)of Wistar rats were evaluated. METHODS: The animals, except for the control ones (Nuvilab® diet: 3.48kcal/g), were fed with a chocolate-based diet (4.17 kcal/g) during 2 months in order to induce obesity. The animals were then distributed into 6 groups, according to the introduction of baru extract diet as well as to swimming training: Sedentary Control (SC); Trained Control (TC); Sedentary Baru (SB); Trained Baru (TB); Sedentary Chocolate (SCho) and Trained Chocolate (TCho). The trained animals were subjected to swimming exercise supporting overload equivalent to 2% of body weight, during 8 weeks, 5x/week, and 1h/day. At the end, the animals were killed and the TGLhep content was determined. The retroperitoneal (RET), inguinal (IN), and omental (OM) fat tissues were excised, weighted, and submitted to adipocyte area evaluation. RESULTS: The hypercaloric diet increased both body weight and cell areas of RET if compared to the control diet (P TB: 0.88 ± 0.43mg.100mg-1; SCho: 1.77 ± 0.64 > TCho: 0.86 ± 0.41mg.100mg-1). CONCLUSION: In the conditions of the present study, the exercise training protocol seemed more effective than the diet protocol in attenuating lipid tissue accumulation in rats.

Propofol effects on the morphology of rat testes subjected to testicular ischemia­reperfusion

PURPOSE To evaluate the effects of propofol as an inhibitor of tissue injury in testicular ischemia-reperfusion in rats. METHODS 30 Wistar rats were assigned to one of three groups of 10 animals: G1, testicular exposure alone; G2 and G3: testicular ischemia caused by left spermatic cord torsion of 720º. In G3, propofol was administered intraperitoneally at 20 mg/kg/h 45 minutes after spermatic cord torsion. In G2 and G3, spermatic cords were detorsioned after 60 min. In all three groups, testes were subsequently repositioned in the scrotum. After 90 days, bilateral orchiectomy was performed for histological examination. RESULTS No abnormalities in seminiferous tubules were found in G1. In G2, 86.6% of left testes exhibited abnormalities, in contrast with 67.8% for right testes. In G3, these proportions were 57.3% and 45.6%, respectively. A statistically significant difference was found between G2 and G3. CONCLUSION Propofol reduced the tissue damage in rat testes subjected to ischemia-reperfusion caused by spermatic cord torsion.

O papel da poliuretana de mamona como substituto do enxerto ósseo autógeno em coelhos

BACKGROUND: The aim was to verify the integration of the castor oil plant polyurethane, applied in the form of handmade biomass, as a biological alternative substitute of the autogenous bone graft in rabbits. METHODS: Twenty rabbits (New Zealand) were submitted to a standard femoral condilar defect, with dimensions of 6x10mm, and ramdomly assigned for implantation of autogenous bone graft in one side and castor oil plant polyurethane in the other. The animals were observed for a period of 45 and 90 days. Evaluation of the macro and microscopic studies were analysed with statistical tests (p < 0.05). RESULTS: Macroscopic analysis showed that the presence of femoral fractures were not significant in both groups. In all autogenous bone grafts there were the presence of cortical healing (p = 0.0010), at 45 and at 90 days, while in the femurs that received polyurethane, this healing was absent at 45 days. Regarding the presence of ripe bone in the transition area between the implant and the receiving bone, the microscopic observation showed that it was completely absent, at 45 days. At 90 days, it was present in all animals that received autogenous bone graft (p = 0.0010) and in none of those who received polyurethane of castor oil plant, showing the presence of only immature bone. CONCLUSION: Castor oil plant polyurethane becomes complete to the receiving bone in a slower fashion than autogenous bone graft. However the proposal for the use of a handmade biomass to fill out the bone flaw, was shown feasible and promising in the research of the castor oil plant polymer as biological bone substitute.

Estudo do reparo ósseo com matriz óssea bovina desvitalizada e calcitonina em ratos

SUMMARYPURPOSE: To study the effect of the calcitonina in the repair of femoral defect fulfilled with bovine bonedevitalized matrix and calcitonin in rats. METHODS : Forty eight adult male Wistar rats were distributed into two group with 24 animals. Bilateralfemoral defects with 2mm of diameter were produced in the femoral shaft and fulfilled with bovine bonedevitalized matrix. The experimental group received calcitonin 0,05mL intramuscular, in the immediatepostoperative period; the control group received 0,05mL of saline solution. The animals were sacrificed with7, 14 and 21 days and the femurs were submitted the clinical, microscopic and histometric evaluation. Thedata was submitted a statistical evaluation with Student “t”, Kruskal-Wallis and Mann-Whitney. RESULTS : The clinical results didn’t show difference between the control and experimental groups. In theoptical microscopy the defects showed inflammatory reaction and active bony formation in the proximities ofthe bovine bony fragments. The quantitative analysis showed larger bony formation in the initial phases of thereparative osteogenesis in the experimental group (Z=4,82 and Z=4,43), without differences in relation to theinflammatory reaction in both groups.

Comparação entre hidroxiapatita porosa de coral e enxerto ósseo autógeno em coelhos

A transplantacao de osso autogeno continua sendo usada com sucesso, apesar das limitacoes que apresenta, principalmente no que se refere a morbidade aumentada, operacoes adicionais e aumento do custo. O objetivo desta pesquisa foi verificar a integracao da hidroxiapatita porosa de coral como alternativa biologica, em forma de cerâmica, para substituir o enxerto osseo autogeno. Foram utilizados 42 coelhos albinos (Nova Zelândia), submetidos a defeito padrao em 84 condilos femorais, e implantacao aleatoria, em cada lado, de enxerto osseo autogeno ou hidroxiapatita porosa. Foram avaliados os aspectos da evolucao clinica diaria dos animais. Apos duas, quatro e doze semanas, grupos de 14 animais foram sacrificados e feita a avaliacao radiologica e macroscopica da integracao dos enxertos. Pecas das regioes operadas foram colhidas para estudo histologico dessa integracao. Os resultados macroscopicos mostraram que a integridade ossea, coloracao, cicatrizacao da cortical e mobilidade dos implantes nao foram estatisticamente significantes para os dois tipos de enxertos, nos diferentes tempos de observacao. A diferenca de uma progressiva e melhor integracao dos enxertos ocorreu apenas quando se compararam os tres tempos de observacao, e foi considerada como consequencia direta da evolucao natural do processo cicatricial. Os parâmetros radiologicos de integracao seguiram o mesmo padrao dos achados macroscopicos. Os achados microscopicos mostraram que o aparecimento de tecido osseo maduro e retardado nos enxertos de hidroxiapatita com a ocorrencia de cavidades cisticas. Concluiu-se que a hidroxiapatita porosa de coral foi um substituto adequado ao enxerto osseo autogeno em coelhos.

The use of resorcine adhesive in repairing osteochondral's defect in knees of rabbits

PURPOSE To study the morphology of the articulation of the knee of rabbits after the repairing of the defect osteochondral standardized with resorcina adhesive or metallic synthesis. METHODS The procedure was to the creation of the defect osteochondral in femoral medial condylus of the knee of 80 rabbits, The animals were distributed in two groups with continuations of 7 and 42 days and submitted to the technique G (resection and retreat of the fragment osteochondral of the femoral medial condylus and relocation with resorcina adhesive), technique S (resection and retreat of the fragment osteochondral of the femoral medial condylus and relocation and metallic synthesis) or technique C (resection and retreat of the fragment osteochondral of the femoral medial condylus, leaving the empty standard defect the control). It was Made clinical study, radiographic, macroscopic and histological in two groups. RESULTS the resorcina adhesive provokes: necrosis of the fragment osteochondral in 100% and 95%, degeneration 90% and 100%, free body in 80% and 65% respectively in the group I and II; compared with the metallic synthesis that it presented: necrosis in 25% and 35%, degeneration 25% and 35%, free body in 35% and 10% respectively in the group I and II. CONCLUSION the resorcinol adhesive, related with the necrosis, cartilaginous degeneration and detachment of the fragment osteochondral lives frequently that the metallic synthesis.

Morphology of autogenous bone graft and castor oil polyurethane in the infraorbital rim of rabbits: a comparative study

PURPOSE Morphological study comparing castor oil polyurethane and autogenous bone graft to repair bone defect in zygomatic bone of rabbits. METHODS Twenty-four adult, male New Zealand rabbits were randomly distributed between two groups of twelve. Bone defects of 5mm in diameter were cut through the zygomatic bone and filled with polyurethane discs in the experimental group or autogenous bone harvested from the tibia in the control group. Animals were sacrificed after 30, 60 or 90 days, and the zygomatic bones were macro- and microscopically analyzed. Students, Fishers, chi-squared and McNemars tests were used for statistical analysis. RESULTS Both the castor oil polyurethane and the autograft adapted well to the defect, with no need for fixation. Fibrous connective tissue encapsulated the polyurethane, but no inflammation or giant cell reaction was observed. Acidophilic and basophilic areas were observed inside the micropores of the polyurethane, suggesting cell nuclei. After 90 days, bone repair with a lamellar pattern of organization was observed in the control group. CONCLUSION The castor oil polyurethane was biocompatible and did not cause inflammation. It may be considered an alternative to fill bone defects.

Osteointegração de osso bovino desvitalizado, hidroxiapatita de coral, poliuretana de mamona e enxerto autógeno em coelhos

PURPOSE: To study comparatively devitalized bovine bone, porous coralline hydroxyapatite, castor beans polyurethane implants and autograft in the repair of 6x10mm bony defect in femur of rabbits. METHODS: Ninety six New Zealand rabbits were distributed in 4 groups conforms the material of replacement of the bony defect. After following of 4 and 12 weeks, the pieces were submitted the macroscopic, microscopic, radiographic, tomographic and histometric analysis. To data was applied Kruskal-Wallis, Mann-Whitney, Fisher, t-Student and qui-square statistical tests. RESULTS: The autograft showed greatest osteogenic potential; the devitalized bovine bone produces larger inflammatory reaction, larger number of cystic cavities and slowness integration; the porous coralline hydroxyapatite maintains the initial radiodensity; devitalized bovine bone and castor beans polyurethane implants showed increased radiodensities as they were invaded by the bony formation. CONCLUSION: Devitalized bovine bone implants induces slower bony formation, when compared to the autograft, porous coralline hydroxyapatite and castor beans polyurethane implants.

Correlação entre os aspectos ultra-sonográficos e morfológicos da cicatrização de uma lesão muscular em coelhos

The ultrasonography is frequently used to diagnose muscular lesion and to accompany the scaring. The goal of this research was to verify the correlation between the ultrasonographic image and the macroscopic one, having at the end, the histologic correspondent study. Thirty rabbits of New Zealand race have been used, submitted to muscle tibial cranial complete lesion, evaluated with ultrasonography, photographs during the surgery (macroscopy) and histologic study (microscopy) in different period during the sacrification (1st, 2nd and third week). We conclude that it exists correlation among the ultrasonographics, macroscopics and microscopics images.