Scielo RSS <![CDATA[Acta Cirurgica Brasileira]]> vol. 32 num. 11 lang. en <![CDATA[SciELO Logo]]> <![CDATA[<strong>Qualitative analysis of the viability of autogenous fat grafts grafted in different environments of interstitial pressure. Preliminary results and description of a new experimental model in mini-pigs</strong>]]> Abstract Purpose: To evaluate the feasibility of an experimental model of autologous fat graft (AFG) in different interstitial pressure (IP) environments. Methods: Three mini-pigs(Minipig-BR) with age of 8 months (weight: 25-30 kg) were used. AFG were collected from the bucal fat pad, and grafted in the intramuscular pocket (biceps femoralis muscle). IP model was based on a fusiform ressection followed by primary closure “under tension”. A blood pressure catheter located in the intramuscular region connected to a pressure module was applied to quantify IP. Results: The mean operative time was 236 min (210 - 272 min). All the AFG and muscular segments were removed successfully. Average interstitial pressure CP and H were 3 and 10.6 mmHg respectively. The AFG were biopsied for histopathological analysis 30 days after graft. Hematoxylin-eosin staining and immunohistochemical analyzes (TNF-alpha, CD31 and Perilipine with monoclonal antibodies) were employed. Conclusion: The data show that minipigs model could be used as a recipient site for autologous fat graft techniques and allow the development of studies to explore the AFG intake and pathophysiology response. <![CDATA[<strong>Comparative study of intraperitoneal adhesions related to light-weight polypropylene mesh and type I polymerized and purified bovine collagen coated light-weight polypropylene mesh in rabbits</strong>]]> Abstract Purpose: To compare the effectiveness of light-weight polypropylene mesh coated with polymerized and purified bovine type I collagen (Surgidry HNB) in the treatment of abdominal wall defect and the degree of adhesion formation. Methods: Two types of polypropylene mesh were implanted after creation of defect measuring 6.0cm X 5.5cm in the anterior abdominal wall of 32 male New Zealand breed rabbits, divided in two groups (n = 32): (1) light-weigh macroporous polypropylene, (2) type I polymerized and purified bovine collagen coated light-weigh macroporous polypropylene. These animals were further accessed for adhesions, histological evaluation of inflammation and wall’s thickness. Results: The percentage of the area adhered in group 1 (62.31 ± 16.6) was higher compared to group 2 (22.19 ± 14.57) (p &lt;0.05). There was an association between the percentage of the covered area by adhesions and the type of adhesion, toughness and the scores obtained by the adhesion score by correlation analysis (p &lt;0.05). There was no difference between the groups in any variables in relation to the degree of inflammation. Conclusion: The purified type I bovine collagen coated light-weigh polypropylene mesh showed to be effective in the repair of abdominal wall defects and reducing adhesion formation. <![CDATA[<strong>Hyperbaric oxygenation and the genic expression related to oxidative stress in the heart of mice during intestinal ischemia and reperfusion</strong>]]> Abstract Purpose: To investigate the effects of hyperbaric oxygenation (HBO) on intestinal ischemia and reperfusion (IR) injury, we evaluated the expression of 84 genes related to oxidative stress and the antioxidant response in mouse hearts. Methods: Four groups were subjected to 60 minutes of intestinal ischemia followed by 60 minutes of reperfusion: IRG, ischemia and reperfusion group without HBO; HBO-IG, which received HBO during ischemia; HBO-RG, which received HBO during reperfusion; and HBO-IRG, which received HBO during ischemia and reperfusion. The control group (CG) underwent anesthesia and laparotomy and was observed for 120 minutes. The (RT-qPCR) method was applied. 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: Eight genes (9.52%) were hyperexpressed in the IRG. When the HBO groups were compared to the IRG, we found a decrease in the expression of eight genes in the HBO-IG, five genes in the HBO-RG, and seven genes in the HBO-IRG. Conclusion: The reduction in the expression of genes related to oxidative stress and antioxidant defense following HBO in mouse hearts resulting from intestinal IR injury was more favorable during the ischemic period than during the reperfusion period. <![CDATA[<strong>Nandrolone decanoate appears to increase bone callus formation in young adult rats after a complete femoral fracture</strong>]]> Abstract Purpose: To evaluate the influence of nandrolone decanoate on fracture healing and bone quality in normal rats. Methods: Male rats were assigned to four groups (n=28/group): Control group consisting of animals without any intervention, Nandrolone decanoate (DN) group consisting of animals that received intramuscular injection of nandrolone decanoate, Fracture group consisting of animals with a fracture at the mid-diaphysis of the femur, and Fracture and nandrolone decanoate group consisting of animals with a femur fracture and treatment with nandrolone decanoate. Fractures were created at the mid-diaphysis of the right femur by a blunt trauma and internally fixed using an intramedullary steel wire. The DN was injected intramuscularly twice per week (10 mg/kg of body mass). The femurs were measured and evaluated by densitometry and mechanical resistance after animal euthanasia. The newly formed bone and collagen type I levels were quantified in the callus. Results: The treated animals had longer femurs after 28 days. The quality of the intact bone was not significantly different between groups. The bone callus did show a larger mass in the treated rats. Conclusion: The administration of nandrolone decanoate did not affect the quality of the intact bone, but might have enhanced the bone callus formation. <![CDATA[<strong>The expression of endothelial and inducible nitric oxide synthase and apoptosis in intestinal ischemia and reperfusion injury under the action of ischemic preconditioning and pentoxifylline</strong>]]> Abstract Purpose: To investigate the expression of nitric oxide synthase (NOS) and apoptosis associated with ischemic preconditioning (IPC) and pentoxifylline (PTX) in intestinal ischemia (I) and reperfusion (R) injury. Methods: Thirty male rats were assigned to 5 groups: (CG), no clamping of the superior mesenteric artery (90 minutes); (IR-SS) saline + ischemia (30 minutes) + reperfusion (60 minutes); (IR-PTX) PTX + ischemia (30 minutes) + reperfusion (60 minutes); (IPC-IR-SS) 5 minutes of ischemia + 5 minutes of reperfusion (IPC) + saline + I(30 minutes)+R(60 minutes); and (IPC-IR-PTX) IPC + PTX + I(30 minutes)+ R(60 minutes). Results: The application of IPC and PTX showed a significantly lower immunohistochemistry reaction for active caspase-3 (P&lt;0.05) compared to IR+SS. The number of cells immunoreactive to BCL-2 was higher in the IR-PTX group (P&gt;0.05). The NOS-2 expression (qRTPCR) in the IR-PTX group (P&lt;0.05) was higher than the values for the IPC+IR-SS and IPC-IR-PTX groups. The NOS-3 expression was significantly upper in the IPC-IR-PTX group than in the CG (P&lt;0.05), the IR-SS (P&lt;0.05) and the IR-PTX (P&lt;0.05) groups. Conclusions: The BCL-2 and active caspase-3 showed beneficial effects on PTX and IPC. The expression of NOS-2 and NOS-3 in the IPC and IPC-PTX groups showed no synergistic effect. <![CDATA[<strong>Perconditioning associated to hypertonic saline solution on liver function improvement after ischemia/reperfusion injury</strong>]]> Abstract Purpose: To evaluate the effects of hypertonic saline solution associated to remote ischemic perconditioning in liver ischemia/reperfusion injury in rats. Methods: 25 male rats (Wistar) were distributed into five groups: Sham group (S); Ischemia/Reperfusion group (I/R) with 30 minutes of liver ischemia; Remote ischemic perconditioning group (Per) with three cycles of 10 minutes of I/R performed during liver ischemia; Hypertonic saline solution group (HSS) treated with hypertonic saline solution (4ml/kg); Remote ischemic perconditioning + Hypertonic saline solution group (Per+HSS) with both treatments. Results: Per+HSS group showed a lower degree of liver dysfunction in relation to I/R group, whereas the technique of remote ischemic perconditioning isolated or associated with saline solution significantly improved liver function and reduced histological damage. Conclusion: Remote ischemic perconditioning associated or not to saline solution promoted reduction of acute liver injury induced by ischemia/reperfusion. <![CDATA[<strong>Topical action of Buriti oil <em>(Mauritia flexuosa L.)</em> in myositis induced in rats</strong>]]> Abstract Purpose: To analyze the topical effects of Buriti oil (Mauritia flexuosa L.) in induced myositis in rats. Methods: Thirty six male rats divided into three groups: Control group (C), induced myositis group (MI) and induced myositis group reated with Mauritia flexuosa L. (MT). After inducing myositis with 1% acetic acid, was topically applied 0.5 ml of Mauritia flexuosa L.extract on the posterior region of the right gastrocnemius muscle in animals belonging to group MT, for 7 and 14 days. Results: The neutrophil number there was statistically significant difference, after 7 and 14 days, between groups C and MI (p &lt;0.001) (p&lt;0.01). The group MT there was a significant difference in relation to MI group in both experimental times with (p&lt;0.001). The number of fibroblasts in the 14 days showed that when comparing the groups M and MT the differences were also significant (p&lt;0.001). As for the DLL, in 7 days, there was a significant difference between group C and MI group (p &lt;0.001). When considering the MT group, there was a significant difference in relation to the MI group (p &lt;0.001). Conclusion: The extract of Mauritia flexuosa L. leaves lessened acute and chronic inflammation, increased fibroblast proliferation and reduced macroscopically edema. <![CDATA[<strong>Effect of atenolol pre-treatment in heart damage in a model of intestinal ischemia-reperfusion</strong>]]> Abstract Purpose: To investigate the effects of atenolol in inflammatory mediator and oxidative stress in a myocardial injury by intestinal ischemia/reperfusion in rat model. Methods: Adult Wistar male rats were randomly (n=8), anesthetized and divided in: Sham: submitted to operation only; group SS+IR: intravenous saline infusion following superior mesenteric artery occlusion during 60 minutes (ischemia) and open for 120 minutes (reperfusion); group AT+IR: intravenous atenolol infusion (2 mg/kg) following superior mesenteric artery occlusion during 60 minutes (ischemia) and open for 120 minutes (reperfusion); and group AT+I+AT+R: intravenous atenolol infusion following superior mesenteric artery occlusion during 60 minutes (ischemia) and in the time 45 minutes other atenolol doses were administrated and the artery was open for 120 minutes (reperfusion), all animals were submitted to muscular relaxation for mechanical ventilation. In the end of experiment the animals were euthanized and the hearts tissue were morphology analyzed by histology and malondialdehyde by ELISA, and the plasma were analyzed for tumor necrosis factor-alpha by ELISA. Results: The group SS+IR demonstrated the higher malondialdehyde levels when compared with the atenolol treated-groups (p=0.001) in the heart tissue. The tumor necrosis factor-alpha level in plasma decrease in the treated groups when compared with SS+IR group (p=0.001). Histology analyses demonstrate pyknosis, edema, cellular vacuolization, presence of inflammatory infiltrate and band contraction in the heart tissue of the rats. Conclusion: Atenolol significantly reduce the degree of cardiac damage after intestinal ischemia-reperfusion. <![CDATA[<strong>Tadalafil protector effect during ischemia-reperfusion in rats</strong>]]> Abstract Purpose: To evaluate histological parameters in rat renal tissue after tadalafil use during hot ischemia for 45 minutes and reperfusion for 24 hours. Methods: Twenty rats were divided into 2 groups. In the experimental group 10 mg/kg of tadalafil was used per gavage before the procedure. All cases underwent left partial nephrectomy, followed by 45 minutes of warm ischemia. Left nephrectomy of the remaining kidney was performed after 24 hours from the initial procedure. The histological parameters analyzed were: detachment of tubular cells, accumulation of desquamated cells in the proximal tubule, loss of brush border, tubular cylinders, interstitial edema, leukocyte infiltration, capillary congestion, vacuolization, tubular dilatation, necrosis and collapse of the capillary tuft. Results: Two rats from each group died and were excluded from the study. Tadalafil significantly reduced leukocyte infiltration (p = 0.036). The remaining histological parameters did not show statistical difference between the groups. Conclusion: The use of tadalafil during warm ischemia and reperfusion demonstrates statistically significant reduction of leukocyte infiltration in the renal interstitium. <![CDATA[<strong>Aldefluor protocol to sort keratinocytes stem cells from skin</strong>]]> Abstract Purpose: To investigate the use Aldefluor® and N, N - Dimethylaminobenzaldehyde (DEAB) to design a protocol to sort keratinocyte stem cells from cultured keratinocytes from burned patients. Methods: Activated Aldefluor® aliquots were prepared and maintained at temperature between 2 to 8°C, or stored at -20°C. Next, the cells were collected following the standard protocol of sample preparation. Results: Best results were obtained with Aldefluor® 1.5µl and DEAB 15 µl for 1 x 106 cells, incubated at 37°C for 15 minutes. Flow cytometer range for keratinocyte stem cells separation was evaluated. There were 14.8% of stem cells separated in one sample of keratinocyte culture used to pattern the protocol. After being defined the ideal concentration, the same test pattern was performed in other keratinocyte samples. We observed a final mean of 10.8%. Conclusion: Aldefluor® has been shown as a favorable marking of epidermal keratinocyte stem cells for subsequent separation on a flow cytometer, with detection of 10.8% of epidermal keratinocyte stem cells, in this protocol.