SUMMARYThe left cerebral hemisphere of Mongolian gerbils was used to elucidate the mechanisms of brain edema which develop during cerebral ischemia and after restoration of cerebral blood flow following temporary ischemia. Water content was measured by the tissue-drying method. Sodium and potassium ion concentration was measured by flame photometry. Passage of '"I-albumin (RISA) from blood to the cerebral parenchyma was measured on a gamma scintillation counter. Our findings indicate that pure cytotoxic edema develops during ischemia and during a short period after restoration of cerebral blood flow. Vasogenic edema, which is accelerated by the leakage of plasma constitutents from blood due to blood-brain barrier damage, developed after restoration of the cerebral blood flow. After less than 1 hr of ischemia, restoration of the cerebral blood flow drastically reduced the degree of brain edema. However, restoration of the cerebral blood flow greatly worsened the brain edema following more than 3 hr of ischemia.

Introduction the management of anal fistula remains debatable. The lack of a standard treatment free of complications stimulates the development of new options. Objective to develop an experimental model of anal fistula in rats. Methods to surgically create an anal fistula in 10 rats with Seton introduced through the anal sphincter musculature.The animals were euthanized for histological fistula tract assessment. Results all ten specimens histologically assessed had a lumen and surrounding granulation tissue. There was complete epithelialization of the tract in two samples, halfway epithelialization in one sample and epithelialization of only the outer portion in six samples. Epithelialization was not evident in one tract. Conclusion anal fistulas in rats were histologically proved.

Fluosol-DA (Perfluorochemical Blood Substitute) was investigated in a previous study and found to provide some protection from ischemia and possible usefulness in limiting the size of infarction. In the present study, larger doses over longer periods of acute focal cerebral ischemia were used. Twenty four cats had transorbital ligation of the middle cerebral artery (MCA). The 12 experimental animals were given 20% Fluosol-DA. The control group of 12 received isotonic saline solution. Twenty-four hours after the MCA occlusion, the cats were perfused with saline and phosphate-buffered formalin. The brains were removed and immersed in 10% formalin for 2 weeks. The results of macroscopic and histological examination suggested that, although Fluosol-DA did not provide complete protection from ischemic injury to the brains of the cats treated, it may have helped to slow the development of the pathological changes.

IntroductionIschemic postconditioning has been recognized as effective in the prevention of reperfusion injury in situations of ischemia and reperfusion in various organs and tissues. However, it remains unclear what would be the best way to accomplish it, since studies show great variation in the method of their application.ObjectiveTo assess the protective effect of ischemic postconditioning on ischemia and reperfusion in rats undergoing five alternating cycles of reperfusion and ischemia of 30 seconds each one.MethodsWe studied 25 Wistar rats distributed in three groups: group A (10 rats), which underwent mesenteric ischemia (30 minutes) and reperfusion (60 minutes); Group B (10 rats), undergoing ischemia (30 minutes) and reperfusion (60 minutes), intercalated by postconditioning (5 alternating cycles of reperfusion and ischemia of 30 seconds each one); and group C - SHAM (5 rats), undergoing only laparotomy and manipulation of mesenteric artery. All animals underwent resection of an ileum segment for histological analysis.ResultsThe mean lesions degree according to Chiu et al. were: group A, 2.77, group B, 2.67 and group C, 0.12. There was no difference between groups A and B (P>0.05).ConclusionIschemic postconditioning was not able to minimize or prevent the intestinal tissue injury in rats undergoing ischemia and reperfusion process when used five cycles lasting 30 seconds each one.

Purpose: To compare the use of a new cyanoacrylate-based surgical glue and suture with separate points in skin wounds closure. Methods: Thirty-six rats were subjected to a 4cm dorsal longitudinal incision. Twelve were subjected to simple suture with polyamide 6-0, 12 rats underwent wall synthesis using Dermabond® and 12 was performed cutaneous synthesis with N-2-Butyl-Cyanoacrylate. Twelve of each group was euthanized on the seventh postoperative day, their blood was taken to biochemical tests and a layer of skin and subcutaneous tissue surrounding the surgical scar was randomly divided in two segments, to the submission of tension tests and to histological study. Results: There were no significant difference between groups (p>0.05). In the soft dermis there was more type I collagen production in group I (p<0.05), group II and III was similar re-sults (p>0.05). In the compact dermis, all 3 groups showed similar results (p>0.05). The biomechanical study was similarity between the glue groups (p>0.05) but the group III proved to be different from the others having a higher resistance (p>0.05). Conclusion: This glue does not cause any inflammation or kidney and hepatic toxicity. Polyamide sutures are more resistant and the glue should be used alone only in less tension are-as.