Scielo RSS <![CDATA[Acta Cirurgica Brasileira]]> vol. 30 num. 4 lang. en <![CDATA[SciELO Logo]]> <![CDATA[Action of hyperbaric oxygenation in the rat skin flap]]> PURPOSE: To evaluate the morphology, necrotic area and collagen content in skin flaps of rats subjected to hyperbaric oxygenation (HBO). METHODS: Forty adult rats were divided into four groups: GEC - epilated; GE/HBO - epilated subjected to HBO; GER - epilated submitted to skin flap (2 cm in width /8 cm length in the dorsal area) and GER/HBO - epilated, subjected to skin flap and HBO. HBO (2.4 ATA) was performed for two hours during seven consecutive days. In the eighth day, the rats were anesthetized and the skin flaps were removed and separated into three portions, relative to pedicle fixation. The material fixed in 10% formalin was processed for paraffin embedding; sections were stained by H.E and subjected to picrosirius-red method. The slides examined under light microscopy for evaluation of the collagen content in polarized light microscope and ImageLab(r) software (Bio-Rad). RESULTS: The data showed larger area of necrosis and lower levels of collagen in the three regions of the GER group, whereas in the GER/HBO group the collagen content was similar to the GEC and GE/HBO groups. CONCLUSION: Hyperbaric oxygenation reduced the area of necrosis and preserved the morphology and collagen content in skin flaps of rats. <![CDATA[Evaluation of the anti-inflammatory and analgesic effects of green tea (Camellia sinensis) in mice]]> PURPOSE: To evaluate the anti-inflammatory and analgesic effects of green tea (Camellia sinensis) in mice. METHODS: The anti-inflammatory effect of alcoholic extracts of green tea (AE) was evaluated in a cell migration assay with four groups of six Swiss mice receiving 0.07g/Kg or 0.14g/Kg EA (treatment groups), saline (negative control) or 10mg/Kg indomethacin (positive control) by gavage. One hour later 300 µg carrageen an was administered intraperitoneally or subcutaneously. The analgesic effect was evaluated using four groups of six animals receiving 0.07g/Kg or 0.14g/Kg EA, saline or 10mg/Kg indomethacin subcutaneously, followed 30 minutes later by 1% acetic acid. RESULTS: When administered subcutaneously at either dose (0.07g/Kg and 0.14g/Kg), AE inhibited carrageenan-induced cell migration (p&lt;0.05). However, when administered by gavage, only the latter (0.14 g/Kg) was efficient (p&lt;0.05). AE at both doses (0.07g/Kg and 0.14g/Kg) inhibited abdominal contortions (p&lt;0.05), but the effect was not dose-dependent. CONCLUSION: Green tea was shown to have analgesic and anti-inflammatory properties and may constitute a natural treatment option in chronic inflammatory disorders. <![CDATA[Does alfa lipoic acid prevent liver from methotrexate induced oxidative injury in rats?]]> PURPOSE: To determine the antioxidant and anti-inflammatory effects of alfa lipoic acid (ALA) on the liver injury induced by methotrexate (MTX) in rats. METHODS: Thirty two rats were randomly assigned into four equal groups; control, ALA, MTX and MTX with ALA groups. Liver injury was performed with a single dose of MTX (20 mg/kg) to groups 3 and 4. The ALA was administered intraperitonealy for five days in groups 2 and 4. The other rats received saline injection. At the sixth day the rats decapitated, blood and liver tissue samples were removed for TNF-α, IL-1β, malondialdehyde, glutathione, myeloperoxidase and sodium potassium-adenosine triphosphatase levels measurement and histological examination. RESULTS: MTX administration caused a significant decrease in tissue GSH, and tissue Na+, K+ ATPase activity and which was accompanied with significant increases in tissue MDA and MPO activity. Moreover the pro-inflammatory cytokines (TNF-α, IL- β) were significantly increased in the MTX group. On the other hand, ALA treatment reversed all these biochemical indices as well as histopathological alterations induced by MTX. CONCLUSION: Alfa lipoic acid ameliorates methotrexate induced oxidative damage of liver in rats with its anti-inflammatory and antioxidant effects. <![CDATA[Biocompatibility and osteogenesis of the castor bean polymer doped with silica (SiO<sub>2</sub>) or barium titanate (BaTiO<sub>3</sub>) nanoparticles]]> PURPOSE: To evaluate the biocompatibility and osteogenesis of castor oil polymer doped with SiO2 or BaTiO3 nanoparticles. METHODS: Twenty four male rats Wistar were submitted to bone defect filled with castor oil polymer. The animals were distributed in two experimental groups had been formed with 12 animals each: Group 1 - Castor oil polymer doped with 0.30 grams of SiO2 replacing 0.30 grams of CaCO3. Group 2 - Castor oil polymer doped with 0.30 grams of BaTiO3 replacing 0.30 grams of CaCO3. Euthanasia occurred 30 and 60 days after surgery and the femurs were sent to histological analysis and MEV. RESULTS: The implants were biocompatible and allowed for progressive osteogenesis through osteoconduction in both observation periods. There was significant bone neoformation at 30 and 60 days in both groups within the histomorphometric evaluation, but group 1's osteogenesis was lesser in the 30 and 60-day periods observed when compared to the animals of group 2. The MEV morphometric evaluation evidenced a lesser percentage of osseous tissue filling within the BaTiO2-doped polymer. CONCLUSION: The castor oil polymer doped with SiO2 or BaTiO3 remained biocompatible and allowed for progressive osteogenesis in both observation periods. <![CDATA[Micronucleus test in peripheral blood of rats treated with hyperbaric oxygen after subtotal splenectomy preserving the lower pole]]> PURPOSE: To assess the mutagenic potential of the oxygen inhalation therapy (HBO), by means of the micronucleus test, performed in peripheral blood of rats that underwent subtotal splenectomy with lower pole preservation (ESTPI), after HBO sessions or simulations. METHODS: Eighteen male Wistar rats, were distributed into three groups of six animals: group 1 - submitted to ESTPI and HBO sessions; group 2 - submitted to ESTPI and HBO simulations; group 3 - underwent cyclophosphamide administration. In groups 1 and 2, blood samples from the animals' tails were collected before surgery (T0) and immediately after the 13th HBO session or simulation (T1). In group 3, tail blood samples were collected from animals before (T0) and 24 hours after (T1) cyclophosphamide (CP) delivery. The number of micronucleated normochromatic erythrocytes (MNNCE) was determined by blind counting 2000 normochromatic erythrocytes (NCE) per animal. RESULTS: Micronuclei average after CP delivery in group 3 was higher than before its use, thus confirming the mutagenic activity of this drug (p=0.01). In groups 1 and 2, no significant difference in the average of Micronuclei was observed when comparing it to blood samples before and after the 13th HBO session or simulation. CONCLUSION: The treatment protocol used in this study did not induce Micronucleus formation in animals submitted to ESTPI and HBO treatment or simulation. <![CDATA[Parecoxib reduces renal injury in an ischemia/reperfusion model in rats]]> PURPOSE: To evaluate the effect of parecoxib (an NSAID) on renal function by measuring plasma NGAL (serum neutrophil gelatinase-associated lipocalin) levels in an induced-ischemia rat model. METHODS: Forty male Wistar rats were randomly assigned to one of four groups: Ischemia (I), Ischemia/parecoxib (IP), No-ischemia (NI), and No-ischemia/parecoxib (NIP). Body weight, mean arterial pressure, heart rate, body temperature, NGAL levels, and renal histology were compared across groups. RESULTS: The Ischemia (I) group, which did not receive parecoxib, showed the highest NGAL levels (p=0.001), while the IP group, which received the medication, had NGAL levels similar to those of the non-ischemic (NI and NIP) groups. CONCLUSION: Parecoxib resulted in renal protection in this experimental model. <![CDATA[Renal biomarkers of male and female Wistar rats (Rattus norvegicus) undergoing renal ischemia and reperfusion]]> PURPOSE: To investigate biomarkers of acute renal injury in Wistar rats, subjected to left renal ischemia for 10 minutes, and then compare reperfusion at 24 hours, and at 5, 7, 14 and 21 days after the procedure. METHODS: Eight female and male rats between 60 and 81 days old were used in the Central Animal Facility of the UFMS. Assessed biomarkers included urine protein, urea, creatinine, glucose, sodium, potassium, urine alkaline phosphatase and gamma-glutamyl transferase activities, and protein-to-creatinine ratio; and in serum: urea, creatinine, sodium and potassium, fractional excretion of sodium, potassium, urine flow and creatinine clearance. RESULTS: Greater variance was observed in the parameters at 24 hours and at five days (p&lt;0.05) after reperfusion. On the 21st day, these parameters approximated those obtained for the control group. CONCLUSIONS: Renal ischemia for 10 minutes was sufficient to raise urine levels of protein, glucose, fractional excretion of potassium, urea, creatinine clearance, urine activity of gamma-glutamyltransferase and alkaline phosphatase enzymes in the first 24 hours, up to five days after reperfusion, which may indicate risk of acute kidney injury, according to the RIFLE classification. <![CDATA[Mast cell concentration and skin wound contraction in rats treated with Brazilian pepper essential oil (Schinus terebinthifolius Raddi)]]> PURPOSE: To evaluate wound contraction and the concentration of mast cells in skin wounds treated with 5% BPT essential oil-based ointment in rats. METHODS: Twenty rats, male, of adult age, were submitted to skin surgery on the right (RA) and left antimeres (LA) of the thoracic region. They were divided into two groups: control (RA - wounds receiving daily topical application of vaseline and lanolin) and treated (LA - wounds treated daily with the topical ointment). The skin region with wounds were collected at days 4, 7, 14 and 21 after surgery. Those were fixed in 10% formaldehyde and later processed for paraffin embedding. Sections were obtained and stained by H.E for histopathology analysis. The degree of epithelial contraction was measured and mast cell concentration were also evaluated. RESULTS: The treated group showed higher mast cell concentrations (p&lt;0.05) associated with increased contraction at day 7 and 14 respectively. CONCLUSION: Ointment containing 5% Brazilian pepper tree oil increases mast cell concentration and promotes skin wound contraction in rats. <![CDATA[Biocompatibility of the bacterial cellulose hydrogel in subcutaneous tissue of rabbits]]> PURPOSE: To evaluate the biocompatibility and local sensibility reaction to bacterial cellulose hydrogel (0.8%) implanted in subcutaneous tissue of rabbits. METHODS: Fifteen New Zeland rabbits were randomly allocated into three groups: T1, 7 days, T2, 21 days, and T3, 84 days. The new material was implanted in the subcutaneous tissue of the ear; on the scalp over the periosteum; and on the outer and inner surfaces of the thighs, in the aponeurosis of the muscle. At 7, 21 and 84 postoperative days, the material was collected for histological study. The clinical signs, inflammatory response, angiogenesis and fibrogenesis were variables used for analysis of the biocompatibility and biological reactivity to BCH. Analyses were performed with an AXIO(r) Imager. The statistical tests were performed using the GraphPad Prism 5.0 program(r) RESULTS: The intensity of the inflammatory infiltrate, considering the different cell types (PMN, LMN and GC), was statistically significant, with group T1 different from groups T2 and T3 (p = 0.0124 and p &lt;0.0001, respectively) and T2 different from the T3 group (p = 0.0007). Fibrogenesis grade 1 was the most prevalent in groups T1 (55.4%) and T2 (44.6%). The formation of neovascularization in the group was identified in 84.4% of samples. CONCLUSION: Bacterial cellulose hydrogel (0.8%) is biocompatible, integrating with the subcutaneous tissue of rabbits and inducing tissue remodeling. <![CDATA[Structural study of endopelvic fascia in prostates of different weights. Anatomic study applied to radical prostatectomy]]> PURPOSE: To evaluate the structure of the endopelvic fascia in prostates of different weights. METHODS: We studied 10 patients with BPH (prostates&gt;90g); 10 patients with prostate adenocarcinoma (PAC) (prostates&lt;60g) and five young male cadavers (control group). During the surgery a small sample of endopelvic fascia was obtained. We analyzed elastic fibers, collagen and smooth muscle. The stereological analysis was done with the Image Pro and Image J programs. Means were statistically compared using the one-way ANOVA with the Bonferroni test and a p&lt;0.05 was considered statistically significant. RESULTS: The mean of the prostate weight was 122 g in BPH patients, 53.1g in PAC patients and 18.6g in control group. Quantitative analysis documented that there are no differences (p=0.19) in Vv of elastic fibers and in Vv of type III collagen (p=0.88) between the three groups. There was a significant difference (p=0&lt;0.0001) in the quantification of SMC in patients with prostates &gt;90g (mean=9.61%) when compared to patients with prostates &lt;60g (mean=17.92%) and with the control group (mean=33.35%). CONCLUSION: There are differences in endopelvic fascia structure in prostates&gt;90g, which can be an additional factor for pre-operatory evaluation of radical prostatectomy.