Scielo RSS <![CDATA[Acta Cirurgica Brasileira]]> vol. 33 num. 5 lang. en <![CDATA[SciELO Logo]]> <![CDATA[Effects of remote ischemic preconditioning and topical hypothermia in renal ischemia-reperfusion injury in rats]]> Abstract Purpose: To evaluate whether combining hypothermia and remote ischemic preconditioning (RIPC) results in protection from ischemia-reperfusion (IR). Methods: Thirty-two Wistar rats underwent right nephrectomy and were randomly assigned to four experimental protocols on the left kidney: warm ischemia (group 1), cold ischemia (group 2), RIPC followed by warm ischemia (group 3), and RIPC followed by cold ischemia (group 4). After 240 minutes of reperfusion, histological changes in the left kidney, as well as lipid peroxidation and antioxidant enzyme activity, were analyzed. The right kidney was used as the control. Serum creatinine was collected before and after the procedures. Results: RIPC combined with hypothermia during IR experiments revealed no differences on interventional groups regarding histological changes (p=0.722). Oxidative stress showed no significant variations among the groups. Lower serum creatinine at the end of the procedure was seen in animals exposed to hypothermia (p&lt;0.001). Conclusions: Combination of RIPC and local hypothermia provides no renal protection in IR injury. Hypothermia preserves renal function during ischemic events. Furthermore, RIPC followed by warm IR did not show benefits compared to warm IR alone or controls in our experimental protocol. <![CDATA[Does ureteral access sheat usage lead to permanent damage in the ureter? A placebo controlled trial in a rabbit model]]> Abstract Purpose: To evaluate the clinical stenosis or precursor histological changes that ureteral access sheaths commonly used in ureteroscopic surgeries may cause in the long term in ureter. Methods: In this study, the animals were divided into 9 groups and according to their groups, ureters of the rabbits were endoscopically fitted with 2F and 3F ureter catheters. The catheters were left in place and withdrawn after a specified period of time. All the ureters were excised and evaluated macroscopically, microscopically and histologically. Ureter diameters were measured and FGF-2 (+) labeled fibroblasts were counted in connective tissue as stenosis precursors. Results: Macroscopically or microscopically, no stenosis was found in any group. The ureter diameter of the group that were catheterized for the longest time with the catheter that had the widest diameter was significantly lower than the group with the shorter duration and the catheter with the narrower diameter and the control group. When the groups were compared in terms of their FGF values, there was a significant difference in FGF-2 counts at all three ureter levels (p &lt;0.05). Conclusion: The use of ureteral access sheath may lead to histological changes, as its diameter and duration increase. <![CDATA[Influence of oophorectomy on glycemia and lipidogram]]> Abstract Purpose: To verify the influence of oophorectomy on lipidogram and glycemia. Methods: Fifty six female rats were divided into the following 7 groups (n = 8): group 1 - sham group, group 2 - oophorectomy 30 days, group 3 - oophorectomy 35 days, group 4 - oophorectomy 40 days, group 5 - oophorectomy 45 days, group 6 - oophorectomy 70 days, group 7 - oophorectomy 55 days. Animals were following by number of days according the group. Was evaluated the serum levels of glucose and lipid profile. Results: The oophorectomized rats presented higher glycemia. Groups 3, 4, 6 and 7 had a higher glycemia and LDL levels (except for group 6) and groups 6 and 7 had lowest levels of HDL. Group 7 had highest level of VLDL than oophorectomy groups. There was no difference in triglycerides levels. Conclusion: Oophorectomy was related to dyslipidemia and insulin resistance, mainly after 50th days. <![CDATA[Effect of red propolis on hamster cheek pouch angiogenesis in a new sponge implant model]]> Abstract Purpose: To evaluate the effects of red propolis on cheek pouch angiogenesis in a hamster new model sponge implant. Methods: Forty eight animals divided into eight groups. (Groups I-IV), the animals were treated for 15 days before and 10 days after sponge implantation. (Groups V-VIII), the animals were treated for 10 days after sponge implantation (GI and GV: red propolis 100 mg/kg, GII and GVI: celecoxib 20 mg/kg, GIII and GVII: 1% gum arabic 5 mL/kg, GIV and GVIII: distilled water 5 mL/kg). On the 11th day of implantation, the animals were anesthetized for stereoscopic microscopic imaging and morphometric quantification of angiogenesis (SQAN), followed by histopathological evaluation (H&amp;E). Results: In the SQAN analysis, no significant difference was found between the groups. However, on histology, propolis was found reduce the population of mastocytes in the qualitative analyses (p = 0,013) in the quantitative analyses to reduce the number of blood vessels (p = 0,007), and increase the macrophage count (p = 0,001). Conclusion: Red propolis inhibited inflammatory angiogenesis when administered before andcontinuously after sponge implant, and was shown to have immunomodulating effects on inflammatory cells (mastocytes and macrophages) in a new sponge implant hamster model. <![CDATA[Proliferation of human adipose tissue-derived stem cells stimulated by oil rich in thymol of <em>Lippia origanoides</em>]]> Abstract Purpose: To evaluate the effects of this thymol-rich oil in the proliferation of human adipose tissue-derived stem cells. Methods: Stem cells were isolated from human adipose tissue by liposuction. After the first passage, cells were cultivated in triplicate for three days in control medium and medium supplemented with three oil samples (1.0 μg/mL, 5.0 μg/mL, and 25.0 μg/mL). Cells were analyzed by the MTT assay at passage 1 (P1), and cell proliferation of control and 1 μg/mL groups was determined with a hemocytometer at P2 and P3. Results: Viability of the essential oil-treated cells was significantly higher than the control group at P1 (p = 0.0008). The treatment with the oil, at a concentration of 1 µg/mL, led to increases of 24.8% at P1 and 43.0% at P3 in the rate of cell proliferation compared with control cells. Conclusion: Supplementing culture medium with essential oil of Lippia origanoides increased cell proliferation, especially at later passages. <![CDATA[Capsiate treatment in liver surgeries may compromise its recovery]]> Abstract Purpose: To investigate the effects of capsiate treatment on hepatic hyperplasia in partially hepatectomized rats. Methods: The animals were divided into a Capsiate group (CPH), a Capsiate Post-Partial Hepatectomy group (CPPH) and a Partial Hepatectomy Control group (PH). CPH and CPPH animals received 60 mg/kg/day Capsiate for 30 days. Next, the rats underwent partial hepatectomy. CPPH animals continued to receive treatment for 48 h after partial hepatectomy. Liver tissue and intracardiac blood samples were obtained 24 or 48 h after PH. Results: Capsiate treatment interfered with hepatic parameters, reducing the number of mitoses and apoptosis and increasing blood ALT and alkaline phosphatase concentrations. Conclusion: Capsiate treatment preceding hepatic surgery may compromise the initial period of postoperative recovery. <![CDATA[Fecal peritonitis in aging rat model. Therapeutic response to different antibiotic strategies]]> Abstract Purpose: To evaluate the response of aging rats with sepsis to two different antibiotic regimens. Methods: The study was conducted with 30 aging rats (18 month-old) with autologous feces peritonitis. The animals were divided into three groups: Group 0 received no therapeutic intervention (control), while Group 1 received a single dose of 40 mg/kg meropenem and Group 2 received a single dose of 20 mg/kg moxifloxacin. The intervention in both Groups was made 6 hours after induction of peritonitis. The animals were followed up to 15 days for evaluating morbidity and mortality. The weights at baseline were similar in all groups. Results: At the end of follow-up, weight loss was significantly greater (p=0.0045) in Group 0 (non-intervention controls). Culture from a blood sample at the end of follow-up was positive in all the animals in Group 0, in two animals in Group 1 and in four animals in Group 2. Morbidity/mortality was significantly higher in Group 0 compared to both Groups 1 and 2 (p=0.003) but the scores were not significantly different between Groups 1 and 2 (p=0.6967). Conclusion: Both antibiotic regimens rendered promising results for the treatment of fecal peritonitis. <![CDATA[Evaluation of polyamide surgical mesh as an abdominal ventral implant in rabbits]]> Abstract Purpose: To evaluate abdominal ventral wound healing by using a specific biomaterial, a handmade polyamide surgical mesh. Methods: A surgical incisional defect was made in ten rabbits to simulate a hernia in the ventral abdominal musculature. A polyamide surgical mesh was used in hernioplasty. They were monitored for surgical wound healing, and macroscopically and histologically evaluated at the end of the experiment. The polyamide surgical mesh did not cause foreign body reaction, pain, edema, or infection in the surgical site. The manure production was not affected by intestinal tissue adherences to the mesh, consistent with the ultrasonography result where adherences were not observed and organized scarring tissue formed in the incisional defect. The polyamide mesh was fixed over the abdominal wall, and its external and internal sides were surrounded by a vascularized connective tissue. Results: None of the experimental animals developed adherences from internal organs to the polyamide mesh, except two rabbits where the omentum formed adherence to the internal scarring tissue without present herniation or compromise of the rabbit’s health. Conclusion: Polyamide surgical mesh for hernioplasty presents, in rabbits, excellent biocompatibility, with minimal body adverse reactions and low cost. <![CDATA[Effect of hyperbaric oxygenation on the expression of glutathione peroxidase 4 and lactoperoxidase genes in the lung of isogenic mice after ischemia/reperfusion injury in the small bowel]]> Abstract Purpose: To evaluate the effect of hyperbaric oxygenation (HBO) on the expression of the genes antioxidant glutathione peroxidase 4 (Gpx4) and lactoperoxidase (Lpo) in the lung of mice subjected to intestinal ischemia and reperfusion (IIR). Methods: Control group (CG) in which were subjected to anesthesia, laparotomy and observation for 120 minutes; an ischemia and reperfusion group (IRG) subjected to anesthesia, laparotomy, small bowel ischemia for 60 minutes and reperfusion for 60 minutes; and three groups treated with HBO during ischemia (HBOG + I), during reperfusion (HBOG + R) and during ischemia and reperfusion (HBOG + IR). Studied 84 genes of oxidative stress by the method (RT-qPCR). Genes with expression levels three times below or above the threshold cycle were considered significantly hypoexpressed or hyperexpressed, respectively (Student’s t-test p&lt;0.05). Results: Gpx4 and Lpo were hiperexpressed on IRG, showing a correlation with these genes with lung oxidative stress. Treated with HBO, there was a significant reduction on genic expression on HBOG+I. Conclusion: Hyperbaric oxygenation showed to be associated with decreased expression of these antioxidant genes, suggesting a beneficial effect on the mechanism of pulmonary oxidative stress whenever applied during the ischemia.