Comparative study of peritoneal adhesions after intraperitoneal implantation in rats of meshes of polypropylene versus polypropylene/polyglecaprone versus polyester/porcine collagen

Abstract Purpose To Compare the extent and intensity of adhesions formed between the intra-abdominal organs and the intraperitoneal implants of polypropylene mesh versus polypropylene/polyglecaprone versus polyester/porcine collagen used for correction of abdominal wall defect in rats. Methods After the defect in the abdominal wall, thirty Wistar rats were placed in three groups (ten animals each) for intraperitoneal mesh implant: polypropylene group, polypropylene/polyglecaprone group, and polyester/porcine collagen group. The macroscopic evaluation of the extent and intensity of adhesions was performed 21 days after the implant. Results The polypropylene group had a higher statistically significant impairment due to visceral adhesions (p value = 0.002) and a higher degree of intense adherence in relation to polypropylene/polyglecaprone and polyester/porcine collagen groups (p value<0.001). The polyester/porcine collagen group showed more intense adhesions than the polypropylene/polyglecaprone group (p value=0.035). Conclusions The intraperitoneal implantation of polypropylene meshes to correct defects of the abdominal wall caused the appearance of extensive and firm adhesions to intra-abdominal structures. The use of polypropylene/polyglecaprone or polyester/porcine collagen tissue-separating meshes reduces the number and degree of adhesions formed.

Comparative study of fibrosis induced by Marlex®, Parietex Composite®, Vicryl® and Ultrapro® meshes1

Abstract Purpose: To evaluate the fibrosis induced by four different meshes: Marlex®, Parietex Composite®, Vicryl® and Ultrapro®. Methods: Histological cutouts of abdominal wall were analyzed with polarized light 28 days after the meshes implants and colorized by picrosirius to identify the intensity of collagen types I and III, and their maturation index. Results: When the four groups were compared, the total collagen area analyzed was bigger in groups A and D, with no difference between them. The collagen type I density was bigger in group A, with an average of 9.62 ± 1.0, and smaller in group C, with an average of 3.86 ± 0.59. The collagen type III density was similar in groups A, B and C, and bigger in group D. The collagen maturation index was different in each of the four groups, bigger in group A with 0.87, group B with 0.66, group D with 0.57 and group C with 0.33 (p = 0.0000). Conclusion: The most prominent fibrosis promotion in the given meshes was found on Marlex® (polypropylene mesh) and the Parietex Composite® (non-biodegradable polyester); the collagen maturation index was higher in the Marlex® mesh, followed by Ultrapro®, Parietex Composite® and Vicryl® meshes.

Inflammatory reaction and tensile strength of the abdominal wall after an implant of polypropylene mesh and polypropylene/poliglecaprone mesh for abdominal wall defect treatment in rats

PURPOSE: To compare the inflammatory reaction and the growing resistance of the abdominal wall with the use of poliglecaprone meshes and polypropylene meshes associated with poliglecaprone in the correction of abdominal defects. METHODS: Seventy-seven Wistar rats were divided into three groups: CG (non-operated animals: EG (polypropylene mesh) and UG (polypropylene and poliglecaprone mesh). A muscular and aponeurotic defect was formed and treated according to the group. Evaluations were made after 4, 7, 14, 28 and 56 days. The resistance and inflammatory pattern were studied. RESULTS: There was a gradual and significant gain in resistance, regularly in the EG and irregularly in the UG, which was lower on the 14th day (p=0.008). The inflammatory reaction was acute and more intense in the UG on the fourth day. At all other times, the inflammatory pattern was acute to chronic, similar in both groups, with minimum intensity on the 56th day. CONCLUSION: The greater resistance offered by the polypropylene mesh was regular and ascending, stabilizing on the 28th day, while that of the polypropylene/poliglecaprone was not even. In the end, the resistances were similar. The inflammatory response was greater in the UG on the fourth day and similar at all other times. .

Cecorraphy in single layer using polypropylene and poliglecaprone 25 threads: comparative study in rats / Cecorrafia em plano único com fios de polipropileno e poliglecaprone 25: estudo comparativo em ratos

PURPOSE: To compare sutures with polypropylene and poliglecaprone 25 after partial cecotomy in rats. METHODS: Thirty six rats divided into two groups, A and B, of 18 animals; each group was also divided into three subgroups of six animals sacrificed at 4th, 7th and 14th days after surgery. Were studied the mortality, morbidity, complications attributable to sutures, macroscopy, optical microscopy and measurement of hydroxyproline at the level of the suture. RESULTS: There were no deaths or wound complications such as hematoma, seroma, abscess, evisceration or eventration. On microscopic evaluation reepithelization, coaptation and inflammation in both groups did not differ significantly. The average rate of tissue hydroxyproline found in the samples on the 4th day after surgery, was 21.38 mg/g tissue for group A and 16.68 mg/g for group B; on day 7 after surgery, the average was 15.64 mg/g tissue for group A and 26.53 mg/g for group B; on day 14, the average was 8.09 mg/g tissue for group A and 25.07 mg/g for group B. CONCLUSION: There were no differences on clinical evolution, macroscopic aspect, microscopic data and hydroxyproline concentration on both sutures.

OBJETIVO: Comparar a sutura com fio de polipropileno e poliglecaprone 25 após cecotomia parcial em ratos. MÉTODOS: Trinta e seis ratos foram distribuídos em dois grupos A e B de 18 animais, e cada grupo foi dividido em três subgrupos de seis, sacrificados no 4º, 7º e 14º dias do pós-operatório. Estudou-se a mortalidade, morbidade, complicações atribuíveis às suturas, macroscopia, microscopia ótica e dosagem de hidroxiprolina no nível da sutura. RESULTADOS: Não houve mortalidade ou complicações da ferida operatória como hematoma, seroma, abscesso, evisceração ou eventração. Na avaliação microscópica os critérios de re-epitelização, coaptação e processo inflamatório ambos os grupos não apresentaram diferença significativa. A taxa tecidual média da hidroxiprolina encontrada nas amostras no 4º dia de pós-operatório foi de 21,38 mg/g de tecido para o grupo A e 16,68 mg/g para o grupo B; no 7º dia a média foi de 15,64 mg/g de tecido para o grupo A e 26,53 mg/g para o grupo B; no 14º dia ela foi de 8,09 mg/g de tecido para o grupo A e 25,07 mg/g para o grupo B. CONCLUSÃO: Não houve diferença estatística entre a evolução clínica, avaliação macroscópica, microscopia e dosagem de hidroxiprolina entre as suturas realizadas com os fios estudados.

Estudo clínico e histopatológico da reacão tecidual às suturas interna e externa dos fios monofilamentares de nylon e poliglecaprone 25 em ratos / Clinical and histopathological study of tissue reactivity to monofilament suture materials: nylon and poliglecaprone 25 in rats

OBJETIVOS: Neste estudo realizamos a análise clínica e histopatológica da reacão tecidual dos fios de nylon e poliglecaprone 25 monofilamentares nas suturas interna e externa em ratos. MÉTODOS: Foram utilizados 40 Rattus norvegicus (Wistar) machos. O ato operatório consistiu de incisão e divulsão dos planos muscular e cutâneo realizadas na região posterior das coxas dos animais. As suturas internas e externas da coxa direita foram realizadas com o fio de nylon nº5-0, e na coxa esquerda aplicamos o poliglecaprone 25 nº5-0. Os animais foram divididos em 4 grupos (n=10) de acordo com o tempo pós-operatório G1 (7 dias), G2 (14 dias), G3 (21 dias) e G4 (28 dias). Para a avaliacão cínica foi considerada a ocorrência de deiscência, de exsudato e edema. Na análise histopatológica objetivou-se avaliar reacão inflamatória, células gigantes de corpo estranho, proliferacão fibroblástica e fibrose. RESULTADOS: Clinicamente, não foram observadas alteracões nos grupos estudados. Histopatologicamente a reacão inflamatória, presenca de células gigantes de corpo estranho, proliferacão fibroblástica e fibrose foram maiores nas suturas internas realizadas com Nylon. Nas suturas realizadas com poliglecaprone 25 essa reacão declinou com o passar do tempo pós-operatório. CONCLUSAO: De acordo com a metodologia empregada podemos concluir que as suturas externas realizadas com nylon induziram menor reacão tecidual, enquanto que nas suturas internas este fio contribuiu para perpetuar a reacão tecidual. As suturas externas realizadas com poliglecaprone 25 apresentaram maior reacão tecidual, e suturas internas realizadas com o mesmo fio a reacão tecidual declinou na medida em que o fio estava sendo absorvido.

Synthetic fibres and health: an one review

Este artigo de revisäo abrange o conhecimento atual sobre fibras sintéticas e toxicidade respiratória. Säo abordadas, de forma padronizada, evidências experimentais e clínicas sobre os efeitos respiratórios näo-malignos e malignos da exposiçäo a fibras de vidro (fibras, filamentos continuos e microfibras) lä de vidro, lä de rocha, lä de escória, fibras cerâmicas refratárias e fibras orgânicas sintéticas (aramidas e fibras de carbono). Para alguns grupos, ainda näo há evidências suficientes que os indiquem como substitutos seguros para aplicaçöes industriais. É enfatizada a necessidade de analisar-se näo somente o potencial carcinogênico da fibra mas também a sua efetiva forma de utilizaçäo em ambientes de trabalho