Acute systemic response to intraperitoneal implantation of polypropylene mesh/chitosan-based film composite in pigs.

PURPOSE: To assess the systemic response of pigs to the intraperitoneal implantation of polypropylene mesh associated with chitosan-based film with a degree of deacetylation of 95%. METHODS: Blood samples were collected 24 hours before, and two and seven days after surgery. Systemic reactions were evaluated based on white blood cell count, C-reactive protein, and total serum protein, albumin and globulin levels. RESULTS: The systemic response was proportional to the composite response induced by polypropylene mesh, and the tissue inflammatory response was higher in the PP group (p=0.0033). CONCLUSION: The polypropylene mesh/chitosan-based film composite did not elicit a systemic response in pigs.

Acute systemic response to intraperitoneal implantation of polypropylene mesh/chitosan-based film composite in pigs

PURPOSE:To assess the systemic response of pigs to the intraperitoneal implantation of polypropylene mesh associated with chitosan-based film with a degree of deacetylation of 95%.METHODS:Blood samples were collected 24 hours before, and two and seven days after surgery. Systemic reactions were evaluated based on white blood cell count, C-reactive protein, and total serum protein, albumin and globulin levels.RESULTS:The systemic response was proportional to the composite response induced by polypropylene mesh, and the tissue inflammatory response was higher in the PP group (p=0.0033).CONCLUSION:The polypropylene mesh/chitosan-based film composite did not elicit a systemic response in pigs.

Wound Healing and Anti-Inflammatory Effect in Animal Models of Calendula officinalis L. Growing in Brazil.

Calendula officinalis is an annual herb from Mediterranean origin which is popularly used in wound healing and as an anti-inflammatory agent. In this study, the ethanolic extract, the dichloromethane, and hexanic fractions of the flowers from plants growing in Brazil were produced. The angiogenic activity of the extract and fractions was evaluated through the chorioallantoic membrane and cutaneous wounds in rat models. The healing activity of the extract was evaluated by the same cutaneous wounds model through macroscopic, morphometric, histopathologic, and immunohistochemical analysis. The antibacterial activity of the extract and fractions was also evaluated. This experimental study revealed that C. officinalis presented anti-inflammatory and antibacterial activities as well as angiogenic and fibroplastic properties acting in a positive way on the inflammatory and proliferative phases of the healing process.

Angiogenic activity of Calendula officinalis flowers L. in rats / Atividade angiogênica das flores da Calendula officinalis L. em ratos

Purpose: In this work, angiogenic activity of Calendula officinalis L. (Asteraceae) ethanolic extract and dichloromethane and hexanic fractions were evaluated, considering medicinal properties, especially healing activity, are attributed to this plant. Methods: Models using 36 rats and 90 embryonated eggs were used to evaluate healing and angiogenic activities of extracts and fractions of the plant, through the induction of skin wounds and the chorioallantoic membrane, respectively. The effect of vascular proliferation was also tested from the study to verify the intensity of expression of vascular endothelial growth factor (VEGF) in cutaneous wounds in rats. Results: The angiogenic activity of the extract and the fractions was evidenced in both experimental models. It was verified that this effect is not directly related to the expression of VEGF and it could be associated to other pro-angiogenic factors. Conclusion: The healing activity referred to C. officinalis is related, among other factors, to its positive effect on angiogenesis, characterized by the induction of neovascularization.

Objetivo: Neste trabalho a atividade sobre a angiogênese do extrato etanólico (EEC) e das frações diclorometano e hexânica das flores de Calendula officinalis L. (Asteraceae) cultivada no Brasil foram avaliados, visto que propriedades medicinais têm sido atribuídas às flores da planta, destacando-se a atividade cicatrizante. Métodos: Modelos utilizando 36 ratos e 90 ovos embrionados foram usados para avaliar as atividades cicatrizante e angiogênica dos extratos e frações da planta, por meio da indução de feridas cutâneas e da membrana corioalantóide, respectivamente. O efeito proliferativo vascular foi também testado a partir do estudo imunoistoquímico, realizado para verificar a intensidade da expressão do fator de crescimento endotelial vascular (VEGF) na derme de ratos. Resultados: A atividade angiogênica do extrato e das frações foi evidenciada nos dois modelos experimentais empregados. Foi evidenciado que este efeito não estava diretamente relacionado à expressão do VEGF, podendo estar associado a outros fatores pró-angiogênicos. Conclusão: A atividade cicatrizante referida a C. officinalis está relacionada ao seu efeito positivo sobre a angiogênese, e este foi caracterizado pela indução de neovascularização.

Angiogenic activity of Calendula officinalis flowers L. in rats.

PURPOSE: In this work, angiogenic activity of Calendula officinalis L. (Asteraceae) ethanolic extract and dichloromethane and hexanic fractions were evaluated, considering medicinal properties, especially healing activity, are attributed to this plant. METHODS: Models using 36 rats and 90 embryonated eggs were used to evaluate healing and angiogenic activities of extracts and fractions of the plant, through the induction of skin wounds and the chorioallantoic membrane, respectively. The effect of vascular proliferation was also tested from the study to verify the intensity of expression of vascular endothelial growth factor (VEGF) in cutaneous wounds in rats. RESULTS: The angiogenic activity of the extract and the fractions was evidenced in both experimental models. It was verified that this effect is not directly related to the expression of VEGF and it could be associated to other pro-angiogenic factors. CONCLUSION: The healing activity referred to C. officinalis is related, among other factors, to its positive effect on angiogenesis, characterized by the induction of neovascularization.

Evaluation of peritoneal adhesions formation and tissue response to polypropylene - poli (2-hydroxyethyl methacrylate)-(polyHEMA) implant on rats' abdominal wall.

PURPOSE: To verify if the composit poli (2-hydroxyethyl methacrylate)-PolyHEMA/polypropylene mesh implanted in the female rat's abdominal wall could be suitable for the prevention of peritoneal adhesions, and for the evaluation of the tecidual response produced by this biomaterial. METHODS: Polypropylene meshes (Group PP, n=20) and polypropylene meshes coated with a layer of poli (2-hydroxyethyl methacrylate)-PolyHEMA (Group PH, n=20) were implanted on the abdominal wall of Wistar female rats. Ten animals from each group were submitted to euthanasia at 15 and 30 days of the postoperative period. RESULTS: The animals from the group PP presented visceral adhesions on the mesh surface, which was not observed in the ones from group PH. At the histopathological examination foreign body response was observed in both groups, whilst there was a greater intensity of inflammatory response in group PH on both moments. CONCLUSION: The poli (2-hydroxyethyl methacrylate) polyHEMA hydrogel associated to polypropylene mesh reduces visceral adhesion formation in rats, although it may be associated to greater inflammatory reaction.

2-hydroxyethyl methacrylate composite - polypropylene mesh for preventing peritoneal adhesions in female dogs.

PURPOSE: To evaluate whether the lining facing the visceral side of polypropylene mesh made with 2-hydroxyethyl methacrylate (p(HEMA)) hydrogel could avoid peritoneal adhesion in female dogs. METHODS: Eight animals (group PP) had a polypropylene mesh implanted to correct a defect in the rectal abdominal muscle, whereas in the other group (group PH) the polypropylene mesh was coated with p(HEMA) composite on the surface facing the peritoneal area. RESULTS: Adhesions were observed on the mesh in 62.5% of the PP group. In the PH group adhesions were present only on the suture lines. CONCLUSION: p(HEMA) hydrogel was well tolerated and effective in avoiding visceral and omental adhesions on the surface of the polypropylene mesh.

Evaluation of peritoneal adhesions formation and tissue response to polypropylene - poli (2-hydroxyethyl methacrylate)-(polyHEMA) implant on rats' abdominal wall / Avaliação da formação de aderências peritoneais e da resposta tecidual ao implante de poli (2-hidroxietil dimetacrilato)-(poliHEMA) na parede abdominal de ratos

PURPOSE: To verify if the composit poli (2-hydroxyethyl methacrylate)-PolyHEMA/polypropylene mesh implanted in the female rat's abdominal wall could be suitable for the prevention of peritoneal adhesions, and for the evaluation of the tecidual response produced by this biomaterial. METHODS: Polypropylene meshes (Group PP, n=20) and polypropylene meshes coated with a layer of poli (2-hydroxyethyl methacrylate)-PolyHEMA (Group PH, n=20) were implanted on the abdominal wall of Wistar female rats. Ten animals from each group were submitted to euthanasia at 15 and 30 days of the postoperative period. RESULTS: The animals from the group PP presented visceral adhesions on the mesh surface, which was not observed in the ones from group PH. At the histopathological examination foreign body response was observed in both groups, whilst there was a greater intensity of inflammatory response in group PH on both moments. CONCLUSION: The poli (2-hydroxyethyl methacrylate) polyHEMA hydrogel associated to polypropylene mesh reduces visceral adhesion formation in rats, although it may be associated to greater inflammatory reaction.

OBJETIVO: Verificar se compósito poli 2-hidroxietil dimetacrilato (PoliHEMA) / tela de polipropileno implantado na parede abdominal de ratas seria adequado para prevenção de aderências peritoneais e avaliar a resposta tecidual desencadeada por este biomaterial. MÉTODOS: Foram implantadas telas de polipropileno - Grupo PP (n=20) e telas de polipropileno revestidas por uma camada de poli 2 (hidroxietil dimetacrilato)-PolyHEMA - Grupo PH (n=20) na parede abdominal de ratas da linhagem Wistar. Dez animais de cada grupo foram submetidos à eutanásia aos 15 e 30 dias de pós-operatório. RESULTADOS: Os animais do grupo PP apresentaram aderências viscerais na superfície da tela, o que não foi observado nos do grupo PH. Observou-se no exame histopatológico resposta tipo corpo estranho nos dois grupos sendo que no grupo PH houve maior intensidade de resposta inflamatória nos dois momentos. CONCLUSÃO: O hidrogel de poliHEMA quando associado à tela de polipropileno reduz a formação de aderências viscerais em ratos, embora possa estar associado à reação inflamatória mais intensa.

2-hydroxyethyl methacrylate composite - polypropylene mesh for preventing peritoneal adhesions in female dogs / Compósito 2-hidroxietil dimetacrilato-tela de polipropileno para prevenção de aderências peritoneais em cadelas

PURPOSE: To evaluate whether the lining facing the visceral side of polypropylene mesh made with 2-hydroxyethyl methacrylate (p(HEMA)) hydrogel could avoid peritoneal adhesion in female dogs. METHODS: Eight animals (group PP) had a polypropylene mesh implanted to correct a defect in the rectal abdominal muscle, whereas in the other group (group PH) the polypropylene mesh was coated with p(HEMA) composite on the surface facing the peritoneal area. RESULTS: Adhesions were observed on the mesh in 62.5 percent of the PP group. In the PH group adhesions were present only on the suture lines. CONCLUSION: p(HEMA) hydrogel was well tolerated and effective in avoiding visceral and omental adhesions on the surface of the polypropylene mesh.

OBJETIVO: Avaliar se o revestimento da face visceral de uma tela de polipropileno com 2-hidroxietil dimetacrilato (p(HEMA)) poderia evitar aderências peritoniais em cadelas. MÉTODOS: Em oito animais (Grupo PP) foram implantadas telas de polipropileno para correção de um defeito do músculo reto abdominal, enquanto em outro grupo (Grupo PH) fez-se a implantação de uma tela de polipropileno cuja face peritonial foi revestida por 2-hidroxietil dimetacrilato (p(HEMA)). RESULTADOS: Foram observados 62,5 por cento de aderências peritoniais sobre a tela nos animais do Grupo PP, enquanto que no Grupo PH estas não ocorreram, exceto sobre a linha se sutura. CONCLUSÃO: O hidrogel de p(HEMA) foi bem tolerado pelos animais e mostrou-se efetivo na prevenção das aderências viscerais e omentais sobre a tela de polipropileno.

Use of chitosan membrane associated with polypropylene mesh to prevent peritoneal adhesion in rats.

The correction of wall abdominal defects often requires the use of implants such as polypropylene meshes. In spite of presenting good tissue acceptance, these biomaterials can migrate to adjacent viscera, promote enterocutaneos fistulas, tissue adherence and visceral erosions. In this work, the barrier effect of chitosan films associated with polypropylene meshes on adhesion formation experimentally induced in Wistar rats was evaluated. The animals were divided into two groups with 10 animals each. Animals in the CPP group were implanted with chitosan films associated with polypropylene meshes, whereas the ones in the PP group received only polypropylene meshes. After 8 days, the animals were submitted to euthanasia using CO(2) and a descriptive study focusing adhesion formation, visceral involvement with sutures and mesh peritonization was performed. Also, subimplanted material was collected for histopathology analysis. The results showed that the CPP group presented weak adhesions to the omentum over the stitch knots in eight animals. In all animals, the meshes were peritonized, not allowing their visualization after removing the chitosan films. In the PP group, six animals presented intestinal adhesions to the meshes and, in one of them, hepatic adhesion to the mesh was observed, besides omentum adhesion on more than 50% of the mesh area. The protective effect of chitosan films when sutured over polypropylene meshes, as well as no exacerbation of inflammation associated to the peritoneal lesions was statistically demonstrated. Therefore, chitosan films can indeed minimize the formation of peritoneal adhesions induced by polypropylene meshes in rats.

Reconstruction of thoracic esophagus with pediculated diaphragmatic flap in dogs.

PURPOSE: To verify whether pediculated diaphragmatic flaps were suitable to correct iatrogenic wounds in dog's esophagus injuries. METHODS: Seven dogs were submitted to resection of a segment of the esophageal wall, which was then corrected by suturing a pediculated diaphragm flap. Endoscopic evaluation of the esophageal wall was done forty days after the surgical procedure. RESULTS: Three animals died, one due to implant ischemia, caused by strangulation of the phrenic artery; other due to wound infection; and the last, due to mediastinitis. Scar retraction was observed, however, there was no stenosis, allowing the passage of a 9,8 mm probe with no difficulty. The limits between the implants and the native esophagus were indistinguishable, and the implant was covered by esophageal mucosa. CONCLUSION: The diaphragmatic flaps are suitable on the restoring of continuity in dog's thoracic esophagus.

Reconstruction of thoracic esophagus with pediculated diaphragmatic flap in dogs

PURPOSE: To verify whether pediculated diaphragmatic flaps were suitable to correct iatrogenic wounds in dog's esophagus injuries. METHODS: Seven dogs were submitted to resection of a segment of the esophagical wall, which was then corrected by suturing a pediculated diaphragm flap. Endoscopic evaluation of the esophagical wall was done forty days after the surgical procedure. RESULTS: Three animals died, one due to implant ischemia, caused by strangulation of the phrenic artery; other due to wound infection; and the last, due to mediastinitis. Scar retraction was observed, however, there was no stenosis, allowing the passage of a 9,8 mm probe with no difficulty. The limits between the implants and the native esophagus were indistinguishable, and the implant was covered by esophageal mucosa. CONCLUSION: The diaphragmatic flaps are suitable on the restoring of continuity in dog's thoracic esophagus.

OBJETIVO: Verificar se retalhos diafragmáticos pediculados seriam adequados para correção de defeitos iatrogênicos do esôfago do cão. MÉTODOS: Sete cães foram submetidos à ressecção de um segmento da parede esofágica, o qual foi corrigido por meio da sutura de um pedículo diafragmático pediculado. Um animal morreu devido à isquemia do implante causada pelo estrangulamento da artéria frênica, outro devido à infecção da ferida cutânea e outro devido a mediastinite. Aos 40 dias após o procedimento fez-se um exame endoscópico dos animais nos cães sobreviventes. RESULTADOS: Observou-se retração cicatricial sem repercutir em estenose, permitindo a passagem de sonda de 9,8 mm, sem dificuldade. Os limites entre os implantes e o esôfago nativo se apresentaram indistinguíveis e o implante estava recoberto por mucosa esofágica. CONCLUSÃO: Os retalhos diafragmáticos são adequados na restauração da continuidade do esôfago torácico do cão.

[Seringueira's latex membrane (Hevea brasiliensis) with and without polylysine 0.1% and marlex mesh for the reconstruction of iatrogenics abdominal wall defects in rats]. / Membrana de látex da seringueira (Hevea brasiliensis), com e sem polilisina a 0,1% e tela de marlex na reconstrução de defeitos iatrogênicos da parede abdominal de ratos.

PURPOSE: To compare seringueira latex membrane implant, with and without polylysine at 0.1% and marlex mesh on the repair of iatrogenic abdominal defects in rats. METHODS: A circular segment block of approximate three centimeters of diameter was sectioned out of the ventral abdominal muscle wall of 31 Wistar rats. The skin was preserved. The animals were divided into three experimental groups: only latex, latex and polylysine at 0.1%, and marlex mesh. Some rats underwent euthanasia at five and some at 120 days after surgery. Fragments of abdominal wall were collected and submitted at histopathologic analysis. RESULTS: The main alterations observed in groups treated with the latex membrane with and without polylysine were dehiscence (21 animals) and evisceration (two animals). The elimination of implant occurred at an average of 13.8 days. These animals presented fiber conjunctive tissue formation, similar to that observed in the group which received the marlex mesh. Other alterations noted were viscera-parietal adherences in all evaluated groups. CONCLUSION: The seringueira' s latex membrane, with or without polylysine 0.1%, when used on the reconstruction of abdominal defects in rats is eliminated at 13.8 days after its implantation, leaving a fiber base of reparation, similar to that observed after marlex mesh implantation.

Membrana de látex da seringueira (Hevea brasiliensis), com e sem polilisina a 0,1 por cento e tela de marlex na reconstrucão de defeitos iatrogênicos da parede abdominal de ratos / Seringueira's latex membrane (Hevea brasiliensis) with and without polylysine 0, 1 percent and marlex mesh for the reconstruction of iatrogenics abdominal wall defects in rats

OBJETIVO: Comparar o implante de membrana de látex da seringueira sem e com polilisina 0,1 por cento e tela de marlex na reparacão de defeitos abdominais iatrogênicos em ratos. MÉTODOS: Ressectou-se em bloco um segmento circular de aproximadamente três centímetros de diâmetro da parede muscular abdominal ventral de 31 ratos Wistar, preservando-se a pele. Os animais foram divididos em 3 grupos: grupo látex sem polilisina, grupo látex com polilisina 0,1 por cento e grupo marlex. Os animais foram sacrificados aos cinco e aos 120 dias após o procedimento cirúrgico. Fragmentos da parede abdominal foram coletados e submetidos à avaliacão histopatológica. RESULTADOS: As principais alteracões observadas nos grupos tratados com as membranas de látex sem e com polilisina 0,1 por cento foram deiscência (21 animais) e evisceracão (dois animais). A eliminacão dos implantes nos grupos tratados com látex ocorreu, em média, aos 13,8 dias. Nestes animais ocorreu a formacão de tecido conjuntivo fibroso, similar ao observado no grupo que recebeu o marlex. Outras alteracões notadas foram aderências viscero-parietais em todos os grupos avaliados. CONCLUSAO: A membrana de látex da seringueira com e sem polilisina a 0,1 por cento, quando utilizada para reconstrucão de defeitos abdominais em ratos é eliminada, em média, aos 13,8 dias após a sua implantacão, deixando uma base fibrosa de reparacão, similar à observada após a implantacão da tela de marlex.

Reconstrução uretral com retalho autógeno de mucosa bucal após uretrostomia, em cães / Urethral reconstruction with autogenous buccal mucosa graft following urethrostomy in dogs

OBJETIVO: Verificar se fragmentos de mucosa bucal autógena poderiam ser adequados para reconstrução uretral na presença de tecido fibroso, e se tal procedimento poderia determinar a formação de fístulas e ou saculações nos sítios implantares. MÉTODOS: Sete cães adultos foram submetidos à uretrostomia pré-escrotal. Após 40 dias, a uretrostomia foi corrigida por meio da implantação de fragmentos de mucosa bucal na parede ventral da uretra. Os animais foram observados durante 40 dias, quando então, foram submetidos a exames radiográficos e sacrificados para estudo histológico. RESULTADOS: Todos os animais apresentaram cistite e fístulas uretro-cutâneas de duração média de vinte dias foram observadas em seis deles. O aspecto radiográfico aos 40 dias após a reconstrução uretral mostrou: continuidade luminal em sete animais e presença de saculações na parede ventral da uretra em seis, sem interferência na qualidade do jato urinário. As características histológicas indicam integração completa da mucosa bucal ao sítio receptor. CONCLUSÃO: O implante em retalho ventral, com fragmentos de mucosa bucal autógena é adequado para correção de defeito uretral produzido por uretrostomia no cão embora possa ocorrer a formação de saculações no sítio do selamento.

Uretroplastia de substituiçäo com segmentos tubulares autólogos de mucosa bucal em cäes / Substitutive urethroplasty with autologous tubular segments of bucal mucosa in dogs

OBJETIVO: Avaliar a reconstruçäo de defeitos experimentais na uretra do cäo com a implantaçäo de segmentos tubulares de mucosa bucal autóloga. MÉTODOS: Procedeu-se à ressecçäo de cerca de 2 cm da uretra peniana de 20 cäes. O defeito produzido foi corrigido por meio da anastomose de fragmento tubular de mucosa bucal autóloga, seccionado do lábio inferior. RESULTADOS: Entre os animais operados, 14 (70 por cento) apresentaram jato urinário normal e seis (30 por cento) evidenciaram estenose confirmada por meio de exame radiológico realizado aos 60 dias do pós-operatório. Durante a necrópsia verificou-se a integridade dos implantes no sulco uretral, associado a infiltrado inflamatório de neutrófilos, linfócitos piócitos e histiócitos. As análises histológicas revelaram que os fragmentos implantados estavam recobertos pelo epitélio uretral. CONCLUSÄO: A implantaçäo de segmentos autólogos de mucosa bucal é adequada para a reconstruçäo de defeitos uretrais iatrogênicos no cäo, embora possa resultar em estenose pós-operatória.

Avaliaçäo da triangulaçäo da anastomose término-terminal de fragmento de mucosa bucal na reconstruçäo uretral: estudo experimental no cäo / Evaluation of triangulation of end-to-end anastomosis using oral mucosa fragment for urethral reconstruction: experimental study in dogs

O uso da mucosa bucal para tratar a estenose uretral tem sido considerado um excelente método alternativo para substituir o tecido uretral. OBJETIVO: Investigar os resultados da realizaçäo da triangulaçäo da anastomose término-terminal de fragmento de mucosa bucal na reconstruçäo uretral. MÉTODOS: Foram utilizados 12 cäes entre 13 e 17 Kg, sem raça definida, aparentemente sadios. Após anestesia, introduziu-se sonda na uretra dos animais que foi mantida durante todo ato operatório. Inicialmente procedeu-se a ressecçäo de um fragmento de mucosa bucal do lábio superior e imerso em soluçäo salina com cloranfenicol aquoso. A seguir procedeu-se a exposiçäo da uretra peniana e ressecou-se um segmento de dois centrímetros. Foi realizada a triangulaçäo da anastomose término-terminal do fragmento de mucosa bucal na reconstruçäo uretral. RESULTADOS: Após 60 dias observou-se a ocorrência de estenose em 25 por cento dos animais. Foram observadas fístulas uretro-cutâneas e extravasamento de contraste no local das anastomoses. CONCLUSÃO: A triangulaçäo da anastomose término-terminal de fragmento de mucosa bucal na reconstruçäo uretral näo evita a ocorrência de estenose.