ABSTRACT
Abstract Background: Pericardium tissue allograft can be used for surgical repair in several procedures. One of the tissue engineering strategies is the process of decellularization. This process decreases immunogenic response, but it may modify the natural extracellular matrix composition and behavior. Objective: The aim of this study was to evaluate the effectiveness of cell removal, maintenance of extracellular matrix properties and mechanical integrity of decellularized human pericardium using a low concentration solution of sodium dodecyl sulfate. Methods: Decellularization was performed with sodium dodecyl sulfate and ethylenediaminetetraacetic acid. Histological analysis, DNA quantification, evaluation of glycosaminoglycans and collagen were performed. Biomechanical assay was performed using tensile test to compare the decellularization effects on tissue properties of tensile strength, elongation and elastic modulus. P < 0.05 was considered significant. Results: There was reduction in visible nuclei present in pericardium tissue after decellularization, but it retained collagen and elastin bundles similar to fresh pericardium. The DNA contents of the decellularized pericardium were significantly reduced to less than 511.23 ± 120.4 ng per mg of dry weight (p < 0.001). The biomechanical assay showed no significant difference for fresh or decellularized tissue. Conclusion: The decellularization process reduces cell content as well as extracellular matrix components without changing its biomechanical properties.
Resumo Fundameto: O enxerto de pericárdio pode ser usado em muitos procedimentos de correção cirúrgica. Uma das estratégias da engenharia tecidual é o processo de descelularização. No entanto, embora esse processo diminua a resposta imunogênica, a descelularização pode modificar tanto o comportamento como a composição da matriz extracelular natural. Objetivos: Avaliar a eficácia da descelularização usando baixa concentração de dodecil sulfato de sódio na remoção celular, na manutenção das propriedades da matriz extracelular e na integridade mecânica do pericárdio humano descelularizado. Métodos: A descelularização foi realizada com dodecil sulfato de sódio e ácido etilenodiamino tetra-acético. Foi realizada análise histológica, quantificação de DNA, e avaliação de glicosaminoglicanos e colágeno. O estudo biomecânico foi conduzido pelo teste de tração para comparar os efeitos da descelularização sobre as propriedades teciduais de resistência à tração, alongamento e módulo de elasticidade. Foi considerado um valor de p < 0,05 como estatisticamente significativo. Resultados: Observou-se uma redução na quantidade de núcleos presentes no pericárdio após a descelularização, apesar de manter quantidades similares de feixes de elastina e de colágeno. As concentrações de DNA do pericárdio descelularizado foram significativamente reduzidas para menos que 511,23 ± 120,4 ng por mg de peso seco (p < 0,001). O teste biomecânico não apontou diferenças entre os tecidos fresco e descelularizado. Conclusão: A descelularização reduziu a concentração de células bem como os componentes da matriz extracelular sem afetar suas propriedades biomecânicas.
Subject(s)
Humans , Adolescent , Adult , Middle Aged , Young Adult , Pericardium/cytology , Sodium Dodecyl Sulfate/pharmacology , Surface-Active Agents/pharmacology , Cell Separation/methods , Tissue Engineering/methods , Pericardium/drug effects , Biomechanical Phenomena , Regenerative Medicine , Tissue ScaffoldsABSTRACT
ABSTRACT Background: Technologies applied to mobile devices can be an important strategy in antibiotic stewardship programs. Objective: The aim of this study was to determine the impact of a decision-making application on antibiotic prescription. Methods: This was an observational, analytical and longitudinal study on the implementation of an antimicrobial guide for mobile application. This study analyzed the period of 12 months before and 12 months after the app implementation at a university hospital based on local epidemiology, avoiding high cost drugs and reducing the potential for drug resistance including carbapenem. Antimicrobials consumption was evaluated in Daily Defined Dose/1000 patients-day and direct expenses converted into USD. Results: The monthly average consumption of aminoglycosides and cefepime had a statistically significant increase (p < 0.05), while the consumption of piperacillin/tazobactam and meropenem was significantly decreased (p < 0.05). The sensitivity to meropenem as well as to polymyxin increased after the app implementation. A decrease in sensitivity to cefepime was observed after introduction of this antibiotic as a substitute of piperacillin/tazobactam for treating intra-hospital infections.There was a net saving of USD 296,485.90 (p < 0.05). Conclusion: An antibiotic protocol in the app can help antibiotic stewardship reducing cost, changing the microbiological profile and antimicrobial consumption.
Subject(s)
Humans , Drug Prescriptions/standards , Telemedicine/economics , Anti-Bacterial Agents/administration & dosage , Drug Prescriptions/economics , Drug Prescriptions/statistics & numerical data , Longitudinal Studies , Anti-Bacterial Agents/economicsABSTRACT
O objetivo desse estudo foi avaliar a morfologia de valvas pulmonares porcinas criopreservadas e/ou descelularizadas para determinar uma solução que remova as células, sem promover danos à matriz extracelular. Valvas pulmonares porcinas foram incubadas por 24h em soluções de deoxicolato de sódio 1% e de dodecil sulfato de sódio 0,1% e 0,3%, com ou sem criopreservação adicional. A avaliação foi feita com microscopia óptica (hematoxilina eosina, orceína acética ou Gomori) e por morfometria. A efetividade das soluções foi variável, mas os melhores resultados foram obtidos com enxertos frescos descelularizados com dodecil sulfato de sódio 0,1%.
The objective of this study was to evaluate the morphology of decelluarized and/or cryopreserved porcine pulmonary valves, to determine a solution capable of completely remove the cells without damaging the extracellular matrix. Porcine pulmonary valves were incubated for 24 hs in sodium deoxicholate 1% or sodium dodecyl sulfate 0.1 and 0.3%, with or without associated cryopreservation. Evaluation was done with optical microscopy (Hematoxilin-Eosin, Acetic Orcein and Gomori) and with morphometric analysis. The effectiviness of the solutions was variable, but the best results were obtained with the sodium dodecyl sulfate solution 0.1%.