RESUMEN
Immunomodulatory effects of chemicals adsorbed to particles with aerodynamic diameter below 0.49 microm (PM(0.5)) collected in winter 2001 at three sampling points (industrial area [LPIn], traffic-influenced urban area [LPCi], and control area [LPCo]) of La Plata, Argentina, were investigated. The sampling of particulate matter was carried out with high-volume collectors using cascade impactors. PM(0.5)-adsorbed compounds were hexane-extracted by accelerated solvent extraction. For immunological investigations, human peripheral blood lymphocytes were activated by phytohemagglutinin and exposed to dimethyl-sulfoxide dilutions of PM(0.5)-extracts for 24h. Vitality/proliferation was quantified using MTT, released interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) by ELISA. Cytokine production but not vitality/proliferation was significantly suppressed by all of the highest extract concentrations. Generally, suppression of IFN-gamma by PM(0.5)-extracts was stronger than those of IL-4. Based on administered mass of PM(0.5), all extracts suppressed IFN-gamma production nearly uniform. Contrary, LPCi-extracts exerted maximum IFN-gamma suppression based either on air volume or regarding PM(0.5)-adsorbed PAH. Also the ranking of PM(0.5)-associated effects on IL-4 production differs in dependence of the chosen reference points, either mass or [microg/ml] or air volume [m(3)/ml] related dust quantities in cell culture. Based on the corresponding air volume, LPCi-extracts inhibited IL-4 production to the maximum extend, whereas suppression of IL-4 was comparable based on concentrations. This indicates that not only the disparate PM(0.5)-masses in air cause varying impacts, but also that disparities in PM(0.5)-adsorbed chemicals provoke different effects on immune responses and shifts in the regulatory balance that might have implications for allergy and cancer development.
Asunto(s)
Contaminantes Ocupacionales del Aire/toxicidad , Contaminantes Atmosféricos/toxicidad , Factores Inmunológicos , Nanopartículas/toxicidad , Argentina , Citocinas/biosíntesis , Relación Dosis-Respuesta a Droga , Polvo/análisis , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunidad Celular/efectos de los fármacos , Interferón gamma/biosíntesis , Interleucina-4/biosíntesis , Monocitos/efectos de los fármacos , Tamaño de la Partícula , Fitohemaglutininas/farmacología , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Salud Rural , Espectrometría de Fluorescencia , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/metabolismo , Sales de Tetrazolio , Tiazoles , Salud UrbanaRESUMEN
RACIONAL: Na cirurgia geral, as correções das hérnias da parede abdominal ocupam lugar de destaque e, cada vez mais, as indicações e usos de telas têm aumentado devido aos melhores resultados. OBJETIVO: Comparar as correções de orifícios produzidos em parede abdominal com telas Parietex® e Surgisis® em contato direto com as vísceras abdominais. MÉTODO: Para os experimentos foram utilizadas 16 coelhas adultas jovens e produção de defeitos triangulares de 2 cm de base por 2,5 cm de altura, comprometendo os planos músculo-aponeurótico-peritoniais da parede abdominal, nos flancos, simétricos à linha média que foram corrigidos com telas retangulares de 3 cm de base por 3,5 cm de altura. No lado direito usou-se tela Parietex® (poliéster/colágeno-polietilenoglicol-glicerol) e no lado esquerdo tela Surgisis® (submucosa intestinal suína). Na avaliação utilizaram-se parâmetros clínico-cirúrgicos, histológicos e imunoistoquímicos. Oito coelhas foram submetidas a eutanásia em 30 dias e as 8 restantes, em 60. Comparou-se a eficiência das duas telas. RESULTADOS: As duas telas provocaram erosões de pele e não ocorreu nenhum caso de hérnia incisional. As aderências ocorreram em todas as telas no primeiro mês e em menor grau e intensidade, no segundo mês; a retração delas foi de 1/3 do tamanho original; a Parietex® provocou menor processo inflamatório; não houve diferença significante de deposição de entre as duas telas; a deposição do colágeno tipo III foi mais intensa no segundo mês em ambas; na remodelação do colágeno a produção da enzima MMP8 foi maior na tela Parietex® no primeiro mês e a enzima MMP13 aumentou no segundo mês em ambas as telas, porém com significância apenas na Parietex®. CONCLUSÃO: As duas telas foram eficientes na correção de hérnias incisionais e com resultados semelhantes, sendo que a Parietex® apresentou menor processo inflamatório, maior quantidade de metaloproteinases MMP8 e MMP13 em relação à Surgisis®.
BACKGROUND: In general surgery, the repair of abdominal wall hernias has a prominent place, and the indications and uses of meshes have increased due to better results. AIM: To compare the repair of induced abdominal wall defects with Parietex® and Surgisis® meshes, in direct contact with abdominal viscera (intraperitoneal mesh). METHOD: For the experiments, were used 16 female young adult rabbits. Two full thickness triangular defects of 2 cm base by 2.5 cm high were created, lateral to the linea alba, one at each side. They were repaired with rectangular meshes of 3 cm base by 3.5 cm high, on the right side with Parietex® mesh (polyester/collagen-polyethylenglycol-glycerol), and on the left side with Surgisis® mesh (lyophilized porcine small bowel submucosa). The evaluation included clinical-surgical findings as well as histological and immunohistochemical parameters. Eight rabbits were subjected to euthanasia after 30 days, and the eight after 60 days. RESULTS: Both meshes induced skin erosions, despite the varying levels of mesh undermining evaluated, no incisional hernia occurred. There were peritoneal adhesions to the surface of both types of meshes after 30 days and in a lower extent and intensity after 60 days. Meshes' shrinking correspond to 1/3 of the original size and Parietex® caused less inflammatory process at the histologic evaluation. Deposition of collagen type I presented no significant difference between the meshes, but deposition of collagen type III was more intense after 60 days, in both groups. Regarding collagen's rearrangement, the production of MMP8 was higher on Parietex® after 30 days, and MMP13 enzyme was increased after 60 days, in both meshes (significant only for Parietex®). CONCLUSION: Both meshes were efficient in the correction of abdominal wall defects, and with similar results, but Parietex® presented less inflammatory process and greater amount of matrix-metalloproteinases MMP8 and MMP13 than Surgisis®.
Asunto(s)
Animales , Femenino , Conejos , Pared Abdominal/cirugía , Hernia Abdominal/cirugía , Peritoneo/cirugía , Mallas Quirúrgicas , Pared Abdominal/patología , Pared Abdominal/fisiopatología , Materiales Biocompatibles/efectos adversos , Modelos Animales de Enfermedad , Hernia Abdominal/enzimología , Hernia Abdominal/patología , Inmunohistoquímica , /metabolismo , /metabolismo , Peritoneo/enzimología , Peritoneo/lesiones , Peritoneo/patología , Estadísticas no Paramétricas , Mallas Quirúrgicas/efectos adversos , Adherencias Tisulares/etiología , Cicatrización de Heridas/fisiologíaRESUMEN
BACKGROUND: In general surgery, the repair of abdominal wall hernias has a prominent place, and the indications and uses of meshes have increased due to better results. AIM: To compare the repair of induced abdominal wall defects with Parietex and Surgisis meshes, in direct contact with abdominal viscera (intraperitoneal mesh). METHOD: For the experiments, were used 16 female young adult rabbits. Two full thickness triangular defects of 2 cm base by 2.5 cm high were created, lateral to the linea alba, one at each side. They were repaired with rectangular meshes of 3 cm base by 3.5 cm high, on the right side with Parietex mesh (polyester/collagen-polyethylenglycol-glycerol), and on the left side with Surgisis mesh (lyophilized porcine small bowel submucosa). The evaluation included clinical-surgical findings as well as histological and immunohistochemical parameters. Eight rabbits were subjected to euthanasia after 30 days, and the eight after 60 days. RESULTS: Both meshes induced skin erosions, despite the varying levels of mesh undermining evaluated, no incisional hernia occurred. There were peritoneal adhesions to the surface of both types of meshes after 30 days and in a lower extent and intensity after 60 days. Meshes' shrinking correspond to 1/3 of the original size and Parietex caused less inflammatory process at the histologic evaluation. Deposition of collagen type I presented no significant difference between the meshes, but deposition of collagen type III was more intense after 60 days, in both groups. Regarding collagen's rearrangement, the production of MMP8 was higher on Parietex after 30 days, and MMP13 enzyme was increased after 60 days, in both meshes (significant only for Parietex). CONCLUSION: Both meshes were efficient in the correction of abdominal wall defects, and with similar results, but Parietex presented less inflammatory process and greater amount of matrix-metalloproteinases MMP8 and MMP13 than Surgisis.