Analysis of tissue inflammatory response, fibroplasia, and foreign body reaction between the polyglactin suture of abdominal aponeurosis in rats and the intraperitoneal implant of polypropylene, polypropylene/polyglecaprone and polyester/porcine collagen meshes

ABSTRACT Purpose To compare tissue inflammatory response, foreign body reaction, fibroplasia, and proportion of type I/III collagen between closure of abdominal wall aponeurosis using polyglactin suture and intraperitoneal implant of polypropylene, polypropylene/polyglecaprone, and polyester/porcine collagen meshes to repair defects in the abdominal wall of rats. Methods Forty Wistar rats were placed in four groups, ten animals each, for the intraperitoneal implant of polypropylene, polypropylene/polyglecaprone, and polyester/porcine collagen meshes or suture with polyglactin (sham) after creation of defect in the abdominal wall. Twenty-one days later, histological analysis was performed after staining with hematoxylin-eosin and picrosirius red. Results The groups with meshes had a higher inflammation score (p < 0.05) and higher number of gigantocytes (p < 0.05) than the sham group, which had a better fibroplasia with a higher proportion of type I/III collagen than the tissue separating meshes (p < 0.05). There were no statistically significant differences between the three groups with meshes. Conclusions The intraperitoneal implant of polypropylene/polyglecaprone and polyester/porcine collagen meshes determined a more intense tissue inflammatory response with exuberant foreign body reaction, immature fibroplasia and low tissue proportion of type I/III collagen compared to suture with polyglactin of abdominal aponeurosis. However, there were no significant differences in relation to the polypropylene mesh group.

Vertical gastrectomy vs. extended vertical gastrectomy: what is the impact on gastroesophageal reflux disease in obese rats? / Gastrectomia vertical vs. gastrectomia vertical ampliada: qual o impacto na doença do refluxo gastroesofágico em ratos obesos?

ABSTRACT Background: Extended vertical gastrectomy is a variation of the vertical gastrectomy technique requiring studies to elucidate safety in relation to gastroesophageal reflux. Aim: To analyze comparatively vertical gastrectomy (VG) and extended vertical gastrectomy (EVG) in rats with obesity induced by cafeteria diet in relation to the presence of reflux esophagitis, weight loss and macroscopic changes related to the procedures. Methods: Thirty Wistar rats were randomized into three groups, and after the obesity induction period by means of a 28-day cafeteria diet, underwent a simulated surgery (CG), VG and VGA. The animals were followed up for 28 days in the post-operative period, and after euthanasia, the reflux esophagitis evaluation was histopathologically performed. Weight and macroscopy were the other variables; weight was measured weekly and the macroscopic evaluation was performed during euthanasia. Results: All animals presented some degree of inflammation and the presence of at least one inflammation criterion; however, there was no statistically significant difference in the analysis among the groups. In relation to weight loss, the animals in CG showed a gradual increase during the whole experiment, evolving to super-obesity at the end of the study, while the ones with VG and EVG had weight regain after the first post-operative period; however, a less marked regain compared to CG, both for VG and EVG. Conclusion: There is no difference in relation to reflux esophagitis VG and EVG, as well as macroscopic alterations, and both techniques have the ability to control the evolution of weight during postoperative period in relation to CG.

RESUMO Racional: A gastrectomia vertical ampliada é uma variação da técnica da gastrectomia vertical, necessitando de estudos a fim de elucidar a segurança em relação ao refluxo gastroesofágico. Objetivo: Analisar comparativamente gastrectomia vertical (GV) e gastrectomia vertical ampliada (GVA) em ratos com obesidade induzida por dieta cafeteria em relação à presença de esofagite de refluxo, perda de peso e alterações macroscópicas relacionadas aos procedimentos. Método: Trinta ratos Wistar foram randomizados em três grupos, e após período de indução de obesidade por meio de dieta cafeteria de 28 dias, foram submetidos a operação simulada (grupo controle GC), gastrectomia vertical (grupo GV) e gastrectomia vertical ampliada (grupo GVA). Os animais foram acompanhados por 28 dias no pós-operatório e, após a eutanásia, foi realizada a pesquisa de esofagite de refluxo através de avaliação histopatológica. Peso e avaliação macroscópica foram as outras variáveis de estudo, sendo o peso aferido semanalmente e a avaliação macroscópica no momento da eutanásia. Resultados: Todos os animais apresentaram algum grau de inflamação e a presença de ao menos um critério de inflamação, porém, não houve diferença estatisticamente significante na análise entre os grupos. Em relação à perda de peso, os animais do GC apresentaram aumento gradativo durante todo experimento evoluindo para super-obesidade ao término do estudo, enquanto os dos grupos GV e GVA tiveram reganho de peso após a primeira semana do pós-operatório, porém, reganho menos acentuado se comparável ao GC, tanto para GV quanto para GVA. Conclusões: Não há diferença em relação à esofagite de refluxo entre GV e GVA, bem como em relação às alterações macroscópicas. Ambas as técnicas têm capacidade de controlar a evolução do peso no pós-operatório em relação ao grupo controle.

The effects of aqueous extract of babassu (Orbignya phalerata) on the pleura and lung parenchyma in rats

PURPOSE: To evaluate macro and microscopically, changes following the use of the aqueous extract of babassu (Orbignya phalerata) in the lung parenchyma and pleura of rats. METHODS: Sixty adult male rats with average weight of 350 g, were randomized into two groups of 30 animals (experimental and control) further divided into sub-groups of 10 to be sacrificed at 48 h, 72 h and 21 days. The substance was injected into the right pleura of the animals. RESULTS: There was intense pleuropulmonary macroscopic reaction with statistically significant differences between groups respectively (p<0.05, p<0.02, p<0.03). Microscopically, no statistically significant difference was evident (p>0.05). CONCLUSION: The aqueous extract of babassu (Orbignya phalerata) was found to be highly irritating to the pleura and lung of rats, evidenced macroscopically by numerous adhesions and inflammation while no major changes were evident microscopically.