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Vascular complication is one of the causes of skin flap healing failure. Sildenafil and tadalafil, a type-5 phosphodiesterase inhibitor, can improve flap viability, however, the action mechanisms involved in this process are still unclear. To assess the effects of orally administered sildenafil and tadalafil on the healing kinetics and skin flap viability, sixty-two Wistar rats were divided into three groups: control (n = 22), sildenafil (n = 20), and tadalafil (n = 20). The solutions were administered orally (dose: 10 mg/kg) immediately after the surgical procedure and then every 24 h. At postoperative days 7 and 14, the skin flap samples were collected, submitted to histological processing and evaluated under optical microscopy. In experimental groups (sildenafil and tadalafil), we found an increased vascularization (p < 0.05) on the 7th and 14th day associated with the ulcer size decrease on the 14th day, although it was not significant. There was a higher influx of neutrophils and a decrease of mononuclear population on the 7th day (p < 0.05). On the 14th day, these differences were observed only in the tadalafil group (p < 0.05). This study suggested positive results with the use of sildenafil and tadalafil as adjuvant drugs in skin flap viability.

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Although breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare disease, its incidence has been increasing. The aim of this study was to assess the risk of BIA-ALCL in women with breast implants. A systematic search was carried out in Pubmed, Scopus, ScienceDirect, LIVIVO, Cochrane Library, Google Scholar, and OpenGrey databases. The risk assessment of bias was based on the Newcastle-Ottawa Scale. The rarity of BIA-ALCL was a major limitation. Although we have found evidence of an increased risk of BIA-ALCL, further studies are needed to understand why some large samples did not present any case of the disease.

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Silicone breast implant is associated with complications inherent to the surgical procedure. Prosthesis coating with polyurethane, however, commonly reduces the incidence of such complications. In this paper, the authors evaluated the inflammatory histomorphometric profile and oxidative damage associated to the implant of polyester urethane sheets. Forty-eight Wistar rats were divided into Sham or polyester urethane groups (n = 8/group) and underwent a polyester urethane implant in the dorsal skinfold. Tissue samples were collected on days seven, 30, and 90 after surgery and subjected to histomorphometric analysis and biochemical tests. Results were analyzed by one-way ANOVA (p ≤ 0.05). Peri-implant tissue samples exhibited characteristic inflammatory response associated with the biomaterial, with increased vascularization on day seven and augmented levels of IL1-b and TNF-a after 30 days. Peri-implant fibrocystic population was small on day seven, but increased considerably after 90 days. A rise in the carbonyl group levels of skin samples in the polyester urethane group was observed on day seven. Findings suggest that polyester urethane sheets undergo biodegradation at an early stage after implantation, followed by increased vascularity and microencapsulation of biomaterial fragments, without persistent oxidative damage. Fiber arrangement inside the collagen matrix results in a fibrotic scar because of polyester urethane degradation.

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BACKGROUND: Hernia correction is a routinely performed treatment in surgical practice. The improvement of the operative technique and available materials certainly has been a great benefit to the quality of surgical results. The insertion of prostheses for hernia correction is well-founded in the literature, and has become the standard of treatment when this type of disease is discussed. AIM: To evaluate two available prostheses: the polypropylene and polypropylene coated ones in an experimental model. METHODS: Seven prostheses of each kind were inserted into Wistar rats (Ratus norvegicus albinus) in the anterior abdominal wall of the animal in direct contact with the viscera. After 90 days follow-up were analyzed the intra-abdominal adhesions, and also performed immunohistochemical evaluation and videomorphometry of the total, type I and type III collagen. Histological analysis was also performed with hematoxylin-eosin to evaluate cell types present in each mesh. RESULTS: At 90 days the adhesions were not different among the groups (p=0.335). Total collagen likewise was not statistically different (p=0.810). Statistically there was more type III collagen in the coated polypropylene group (p=0.039) while type I was not different among the prostheses (p=0.050). The lymphocytes were statistically more present in the polypropylene group (p=0.041). CONCLUSION: The coated prosthesis was not different from the polypropylene one regarding the adhesion. Total and type I collagen were not different among the groups, while type III collagen was more present on the coated mesh. There was a greater number of lymphocytes on the polypropylene mesh.

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ABSTRACT Background: Hernia correction is a routinely performed treatment in surgical practice. The improvement of the operative technique and available materials certainly has been a great benefit to the quality of surgical results. The insertion of prostheses for hernia correction is well-founded in the literature, and has become the standard of treatment when this type of disease is discussed. Aim: To evaluate two available prostheses: the polypropylene and polypropylene coated ones in an experimental model. Methods: Seven prostheses of each kind were inserted into Wistar rats (Ratus norvegicus albinus) in the anterior abdominal wall of the animal in direct contact with the viscera. After 90 days follow-up were analyzed the intra-abdominal adhesions, and also performed immunohistochemical evaluation and videomorphometry of the total, type I and type III collagen. Histological analysis was also performed with hematoxylin-eosin to evaluate cell types present in each mesh. Results: At 90 days the adhesions were not different among the groups (p=0.335). Total collagen likewise was not statistically different (p=0.810). Statistically there was more type III collagen in the coated polypropylene group (p=0.039) while type I was not different among the prostheses (p=0.050). The lymphocytes were statistically more present in the polypropylene group (p=0.041). Conclusion: The coated prosthesis was not different from the polypropylene one regarding the adhesion. Total and type I collagen were not different among the groups, while type III collagen was more present on the coated mesh. There was a greater number of lymphocytes on the polypropylene mesh.

RESUMO Racional: A correção herniária é tratamento realizado rotineiramente na prática cirúrgica. O aprimoramento da técnica operatória e dos materiais disponíveis trouxe grande benefício na qualidade dos resultados cirúrgicos. A inserção de próteses para correção herniária é bem embasada na literatura e tornou-se o padrão de tratamento. Objetivo: Avaliar em modelo experimental dois tipos de próteses diferentes, de polipropileno e polipropileno revestido. Métodos: Foram inseridas sete próteses de cada tipo em ratos Wistar (Ratus norvegicus albinus) na parede abdominal anterior do animal em contato direto com as vísceras. Após o seguimento de 90 dias analisaram-se as aderências intra-abdominais, bem como avaliação por imunoistoquímica e videomorfometria do colágeno total, tipo I e tipo III. Também, fez-se análise histológica com hematoxylina-eosina para avaliação dos tipos celulares presentes em cada tela. Resultados: Aos 90 dias as aderências não foram diferentes entre os grupos (p=0,335). O colágeno total igualmente não foi estatisticamente diferente (p=0,810). O colágeno tipo III foi estatisticamente maior no grupo polipropileno revestido (p=0,039) enquanto o tipo I não diferiu entre as próteses (p=0,050). Os linfócitos foram estatisticamente mais presentes no grupo polipropileno (p=0,041). Conclusão: A prótese revestida não foi diferente da de polipropileno na variável aderência. O colágeno total e tipo I não foram diferentes entre os grupos enquanto que o colágeno tipo III foi mais presente na tela revestida. O número de linfócitos foi maior na tela de polipropileno.

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Breast augmentation with silicone implants is one of the most common procedures performed by plastic surgeons around the world. Capsular contracture is a frequent complication in breast augmentation and reconstructive surgery, that requires invasive intervention. The inflammatory response to implanted mammary prostheses appears to be directly associated to capsular contracture. This review discusses the evidences from rat models studies, on the role of inflammation and fibrosis in capsular contraction and its relation to silicone breast implants surface.

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PURPOSE: We evaluated the hypothesis that induced perioperative hypothermia (32 ± 1ºC) affects the redox balance in the tissue of colonic anastomosis in rats by modifying biochemical enzymatic and non-enzymatic markers related to oxidative stress. METHODS: Forty-eight male Wistar rats were randomly divided into eight experimental groups of six animals each and underwent laparotomy, sigmoid section and immediate anastomosis. Four groups were operated under normothermia (36 ± 1ºC), and the other four under hypothermia (32 ± 1ºC). The animals were reoperated on days 3, 7 and 14 postoperatively, and two groups underwent SHAM at 3 days. From the scar tissue samples, the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) was evaluated, and the levels of non-enzymatic markers of oxidative stress, such as reduced glutathione (GSH) and lipid peroxidation, were measured by the thiobarbituric acid reactive substances (TBARS) assay. The means were compared between groups corresponding to each day of sampling and euthanasia. RESULTS: The hypothermic groups showed a significant reduction on the activity of SOD on day 7 postoperatively, on the activity of CAT on days 7 and 14 postoperatively and on the levels of GSH on day 7 postoperatively. The level of lipid peroxidation was increased in the hypothermia group on day 7 postoperatively and decreased on day 14 compared with the normothermic groups. CONCLUSION: Perioperative hypothermia reduced the activity of the antioxidant enzymes catalase and superoxide dismutase, glutathione levels and increased lipid peroxidation in the scar tissue of colonic anastomoses in rats.

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