Innovative biomaterials can provide a promising new direction for the treatment of bone defects, stimulating a proper repair process, with no damage to adjacent tissues. The purpose of this in vivo study was to evaluate the biocompatibility and the osteoinductive capacity of chitosan-collagen biomembrane and scaffold containing calcium aluminate cement. Eighteen New Zealand white rabbits (Oryctolagus cuniculus) were distributed according to the experimental times of analysis (7, 15 and 30 days). Four bone defects were created in the rabbits calvaria, which were individually filled with the biomembrane, scaffold, blood clot (negative control) and autologous bone (positive control). Histopathological analysis was performed using optical microscope at 32´, 64´, 125´ and 320´ magnifications. Cell response to inflammation and new bone tissue formation was quantified using a score system. The biomembrane group presented greater inflammatory response at 15 days, with significant difference to autologous bone group (p<0.05). There was no statistically significant difference for foreign body type reaction among groups (p>0.05). Concerning new bone formation, linear closure of the defect area was observed more evidently in the group with autologous bone. The scaffold group presented similar results compared with the autologous bone group at 30 days (p>0.05). Both tested biomaterials presented similar biocompatibility compared with the control groups. In addition, the biomembrane and scaffold presented similar osteoinductive capacity, stimulating bone repair process in the course of the experimental time intervals.

The denervation of the intestine with benzalkonium chloride (BAC) reduces mortality and improves weight gain in rats with short bowel syndrome (SBS). Nevertheless, translating these promising findings from bench to bedside is not feasible because BAC promotes peritonitis and irreversible denervation which may be followed by an uncontrolled dilatation of the viscera. The use of botulinum toxin (BT) instead of BAC to achieve the denervation of the remaining small intestine in SBS could be an interesting option because it leads to a mild and transient denervation of the intestine. Methods: Here we evaluated the effects of the ileal denervation with BT in rats with SBS by verifying the body weight variation and intestinal morphological parameters. Four groups with 6 animals each were submitted to enterectomy with an ileal injection of saline (group E) or BT (group EBT). Control groups were submitted to simulated surgery with an ileal injection of BT (group BT) or saline (group C-control). Results: We observed that the treatment of the remaining ileum with BT completely reversed the weight loss associated to extensive small bowel resection. Conclusion: This may provide a new promising approach to the surgical treatment of SBS.

ResumoA paca (Cuniculus paca, Linnaeus, 1766) é um roedor de porte médio, que embora pertença à fauna brasileira, poucas são as informações sobre sua morfologia na literatura especializada. Nesse sentido, objetivouse descrever a origem e as ramificações de suas artérias mesentéricas cranial e caudal no intuito de contribuir com estudos de anatomia comparativa. Foram utilizados dez animais, entre machos e fêmeas, que após o óbito, tiveram sua parede torácica rebatida entre a quarta e a sexta costelas, para a exposição da aorta torácica, a qual foi canulada no sentido caudal e procedeu-se a injeção de solução de neoprene do tipo látex, corado convenientemente, para o preenchimento de todo o sistema arterial. Estas preparações foram fixadas em solução aquosa de formol a 10% por período superior à 72h; em seguida, as peças foram dissecadas e as artérias mesentéricas cranial e caudal identificadas. A artéria mesentérica cranial se originava da aorta abdominal, caudalmente à artéria celíaca, emitindo os seguintes ramos arteriais: pancreaticoduodenal caudal, pancreáticos, jejunais, íleocólicos e cecais. A origem da artéria mesentérica caudal ocorria próximo ao final da aorta abdominal, e este vaso emitia a artéria cólica esquerda e a artéria retal cranial, da qual partiam as artérias sigmóideas. Constatou-se que houve pouca variação no padrão de ramificação das artérias em relação aos referidos roedores e mamíferos domésticos. Palavras-chave:Artéria mesentérica caudal; Artéria mesentérica cranial; Paca; Ramificações AbstractCranial and caudal mesenteric arteries of the paca (Cuniculus paca, L. 1766). The paca (Cuniculus paca, Linnaeus, 1766) is a medium-sized rodent that occurs in Brazil; however, there is little information regarding its morphology. The goal of this study was to describe the origin and branching of the cranial and caudal mesenteric arteries of this rodent in order to contribute to comparative anatomy studies. Ten animals (males and females)