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ABSTRACT Objective To evaluate the in vitro and in vivo toxicities of polyethylene glycol-coated gold nanoparticles synthesized using a one-step process. Methods Gold nanoparticles were prepared via a co-precipitation method using polyethylene glycol, and the synthesis product was characterized. For the in vitro evaluation, a flow cytometry analysis with Annexin V and iodide propidium staining was used to assess cytotoxicity in MG-63 cells labeled with 10, 50, and 100µg/mL of nanoparticle concentration. For the in vivo evaluation, nanoparticles were administered intraperitoneally at a dose of 10mg/kg dose in 10-week-old mice. Toxicity was assessed 24 hours and 7 days after administration via histopathological analysis of various tissues, as well as through renal, hepatic, and hematopoietic evaluations. Results Synthesized nanoparticles exhibited different hydrodynamic sizes depending on the medium: 51.27±1.62nm in water and 268.12±28.45nm (0 hour) in culture medium. They demonstrated a maximum absorbance at 520nm and a zeta potential of -8.419mV. Cellular viability exceeded 90%, with less than 3% early apoptosis, 6% late apoptosis, and 1% necrosis across all labeling conditions, indicating minimal cytotoxicity differences. Histopathological analysis highlighted the accumulation of nanoparticles in the mesentery; however, no lesions or visible agglomeration was observed in the remaining tissues. Renal, hepatic, and hematopoietic analyses showed no significant differences at any time point. Conclusion Polyethylene glycol-coated gold nanoparticles exhibit extremely low toxicity and high biocompatibility, showing promise for future studies.
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Purpose: Liver damage caused by drugs and other chemicals accounts for about 5% of all cases. Methotrexate (MTX), a folic acid analogue, is a first-line synthetic antimetabolite agent routinely used in the treatment of rheumatoid arthritis and other autoimmune and chronic inflammatory diseases. Polyethylene glycol (PEG) has antioxidant activity. In this study, we evaluated biochemically and histopathologically the antifibrotic effect of PEG 3350 administered intraperitoneally to prevent methotrexate-induced liver damage in rats. Methods: A total of 30 male rats including 10 rats was given no drugs (normal group), and 20 rats received single-dose 20 mg/kg MTXfor induced liver injury in this study. MTX was given to 20 rats, which were divided in two groups. Group 1 rats was given PEG30 mg/kg/day (Merck) intraperitoneally, and Group 2 rats % 0.9 NaCl saline 1 mL/kg/day intraperitoneally daily for two weeks. Results: Transforming growth factor beta (TGF-ß), plasma malondialdehyde (MDA), liver MDA, serum tumour necrosis factor alpha (TNF-α), alanine aminotransferase and plasma pentraxin-3 levels and, according to tissue histopathology, hepatocyte necrosis, fibrosis and cellular infiltration were significantly better in MTX+PEG group than in MTX+saline group. Conclusions: PEG 3350 is a hope for toxic hepatitis due to other causes, since liver damage occurs through oxidative stress and cell damage, similar to all toxic drugs.
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Animais , Ratos , Polietilenoglicóis , Fibrose , Fígado , AntioxidantesRESUMO
An analytical method for the simultaneous determination of ethylene glycol and diethylene glycol in beer was developed and validated according to current legislation. This method includes the application of sample dilution with ethanol followed by quantification using gas chromatography coupled to mass spectrometry. All figures of merit were within the limits established by regulation. The recoveries of the analytes, expressed as mean recovery, were between 91.9% and 108.9%. Precision, in terms of repeatability and intermediate precision, was established (relative standard deviations were lower than or equal to 10%). The limits of detection (10.0 and 5.0 mg.L-1 for ethylene glycol and diethylene glycol, respectively) and quantification (15.0 mg.L-1 for ethylene glycol and diethylene glycol) obtained were appropriate. Finally, the present method was applied for determination of ethylene glycol and diethylene glycol in 701 beer samples (from 67 different brands and 128 different labels), proving to be reliable.
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Cerveja/análise , Etilenoglicol/análise , Etilenoglicóis/análise , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
Solid organ transplantation is a very complex process, in which the storage of the graft in a preservation solution is mandatory in order to extend ischemic times and contain further damage. The condition in which the organ is transplanted is critical for the outcome of the organ recipient. The recent emergence of generic versions of organ preservation solutions (solutions with the same composition and under the same legislation as the original versions, but with different brands) compelled us to study whether the standards are maintained when comparing the original and its generic counterpart. Along these lines, we discuss and comment on some aspects concerning this issue of general interest in the organ transplantation field.(AU)
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Preservação de Órgãos/métodos , Preservação de Órgãos/tendências , Polietilenoglicóis , Glutationa , CálcioRESUMO
ABSTRACT Introduction: Adequate bowel preparation is one of the most important factors related to the yield of colonoscopy. Low quality bowel preparation has been associated with lower adenoma detection rates and increased healthcare expenses. Bowel preparation is a major impediment to undergo colonoscopy since it is perceived as an unpleasant experience by patients. Objective: This study was aimed to assess tolerance and acceptability of the bowel preparation using either polyethylene glycol (PEG) or mannitol solution. Materials and methods: We enrolled 140 patients with indications of screening for colorectal cancer or with suspected large bowel diseases. They received either mannitol solution or PEG as bowel preparation. Patients were asked to fill a questionnaire about the bowel preparation experience. Results: Patients perceived more burdensome the preparation with PEG than mannitol for the variables nausea overall experience, post-procedure discomfort, disagreeable flavor, volume ingested and cost (p<0.05). A similar tolerance was reported for abdominal pain, bloating and anal irritation (p>0.05). The acceptability was 82.9% and 71.4% in the Mannitol group and in the PEG group, respectively (p=0.10). Conclusion: Acceptance of the bowel preparation between mannitol solution and PEG was comparable. However, mannitol was better tolerated by the patients in regard to most of the evaluated items.
RESUMEN Introducción: La preparación intestinal adecuada es uno de los factores más importantes relacionados con el rendimiento de la colonoscopía. La preparación intestinal de baja calidad se ha asociado con tasas de detección de adenoma más bajas y mayores gastos de atención sanitaria. La preparación intestinal es un impedimento importante para someterse a una colonoscopía, ya que los pacientes la perciben como una experiencia desagradable. Objetivo: Este estudio tuvo como objetivo evaluar la tolerancia y la aceptabilidad de la preparación intestinal utilizando polietilenglicol (PEG) o solución de manitol. Materiales y métodos: Fueron incluidos 140 pacientes con indicación de pesquisa de cáncer colorrectal o con sospecha de enfermedades del intestino grueso. Los pacientes recibieron solución de manitol o PEG como preparación intestinal. Se pidió a los pacientes que completaran un cuestionario sobre la experiencia de preparación intestinal. Resultados: Los pacientes percibieron más agobiante la preparación con PEG que el manitol para las variables náuseas, experiencia general, molestias posteriores al procedimiento, sabor desagradable, volumen ingerido y costo (p<0,05). Se informó una tolerancia similar para el dolor abdominal, distensión abdominal e irritación anal (p>0,05). La aceptabilidad fue de 82,9% y 71,4% en el grupo de manitol y en el grupo de PEG, respectivamente (p=0,10). Conclusión: La aceptación de la preparación intestinal entre la solución de manitol y el PEG fue comparable. Sin embargo, el manitol fue mejor tolerado por los pacientes con respecto a la mayoría de las variables evaluadas.
Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Catárticos/efeitos adversos , Colonoscopia , Satisfação do Paciente/estatística & dados numéricos , Manitol/efeitos adversos , Polietilenoglicóis/administração & dosagem , Catárticos/administração & dosagem , Estudos Transversais , Estudos Prospectivos , Avaliação de Resultados em Cuidados de Saúde , Manitol/administração & dosagemRESUMO
Abstract Solid organ transplantation is a very complex process, in which the storage of the graft in a preservation solution is mandatory in order to extend ischemic times and contain further damage. The condition in which the organ is transplanted is critical for the outcome of the organ recipient. The recent emergence of generic versions of organ preservation solutions (solutions with the same composition and under the same legislation as the original versions, but with different brands) compelled us to study whether the standards are maintained when comparing the original and its generic counterpart. Along these lines, we discuss and comment on some aspects concerning this issue of general interest in the organ transplantation field.
Assuntos
Humanos , Transplante de Órgãos/métodos , Soluções para Preservação de Órgãos/química , Glutationa/química , Temperatura , Fatores de Tempo , Cálcio/análise , Soluções para Preservação de Órgãos/normasRESUMO
Background: A successful colonoscopy depends, among other factors, on a proper colon cleansing. This variable also affects the acceptance of the patient to carry out the study. Aim: To analyze the efficacy and tolerability of a low volume polyethylene glycol formulation (2 liters), compared to the conventional presentation of 4 liters. Material and Methods: Patients referred for a colonoscopy were randomly divided to receive either two or four liter of polyethylene glycol as bowel cleansing, which was assessed using the Boston score. Raters of the latter were blinded to the volume of polyethylene glycol that the patients used. Results: Seventy-four patients participated in the study. Subjects who received a 4 liters preparation had an average Boston score of 7.78, versus 8.16 for patients who received a volume of 2 liters (p = 0.267). No significant differences in tolerability were observed between both groups. No significant differences in the efficacy and tolerability between a conventional or a reduced volume of polyethylene glycol solution for the preparation of a colonoscopy were observed. These findings may be especially important for subgroups of patients with difficulties for oral administration of fluids.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Polietilenoglicóis/administração & dosagem , Catárticos/administração & dosagem , Colonoscopia/métodos , Inquéritos e Questionários , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Tolerância a MedicamentosAssuntos
Cosméticos/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Dermatoses Faciais/etiologia , Octanóis/efeitos adversos , Urticária/etiologia , Dermatite Alérgica de Contato/diagnóstico , Dermatoses Faciais/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Octanóis/administração & dosagem , Testes do Emplastro , Higiene da Pele/efeitos adversosRESUMO
Resumen Introducción La efectividad de la colonoscopia depende de múltiples factores, destacando la calidad de preparación intestinal y la tolerabilidad que tenga el paciente a la preparación administrada. Objetivo Comparar dos agentes de preparación intestinal, el polietilenglicol (PEG) y el picosulfato de sodiocitrato de magnesio (PSCM) en términos de efectividad y tolerabilidad de la preparación. Pacientes y Método Ensayo clínico aleatorizado en pacientes ambulatorios sometidos a colonoscopia en Clínica INDISA. Evaluando efectividad y tolerabilidad con el Boston Bowel Preparation Score (BBPS) y cuestionario de Lawrence [compuesto por escala Likert, dos preguntas cualitativas y escala visual análoga (EVA)], respectivamente. Resultados 189 pacientes, de los cuales 123 se aleatorizaron a PEG y 66 a PSCM. El BBPS en los pacientes que utilizaron PEG, la media fue 7,51 (DS 1,66) y con PSCM fue 7,12 (DS 1,71) (p = 0,111). Al analizar la tolerabilidad con escala Likert, la media con PEG fue 0,94 (DS 0,68) y con PSCM fue 0,63 (DS 0,61) (p = 0,0004). La EVA con PEG tuvo una media de 7,68 (DS 2,4) y con PSCM de 9,04 (DS 1,59) (p < 0,0001). Al preguntar ausentismo laboral, no hubo diferencias significativas en ambos grupos y al preguntar si ocuparía la misma preparación en una futura colonoscopia, hubo significancia estadística a favor del PSCM (p = 0,026). Conclusión No encontramos diferencias en la efectividad de preparación intestinal al comparar PEG y PSCM, sin embargo, el PSCM es mejor tolerado.
Introduction The effectiveness of colonoscopy depends on multiple factors, being two of the most important ones an adequate bowel preparation and the patient's tolerability to the preparation. Objectives Compare effectiveness and tolerability of two bowel preparation agents, polyethylene glycol (PEG) and sodium picosulfate/magnesium citrate (SPMC). Patients and Methods Randomized clinical trial on outpatients that went into colonoscopy in INDISA Clinic. We evaluated effectiveness and tolerability with Boston Bowel Preparation Score (BBPS) and Lawrence questionnaire [composed by Likert scale, two qualitative questions and Visual Analogue Scale (VAS) for pain], respectively. Results 189 patients, 123 were randomized to PEG and 66 to SPMC. BBPS average in patients in the PEG branch was 7.51 (SD 1.66) and for SPMC 7.12 (SD 1.71) (p = 0.111). Likert scale for evaluating tolerability average for PEG was 0.94 (SD 0.68) and for SPMC 0.63 (SD 0.61) (p = 0.0004). VAS scale for PEG had an average of 7.68 (SD 2.4) and for PSCM 9.04 (SD 1.59) (p < 0.0001). When we asked for workplace absenteeism, there were no significant differences between both groups and when we asked about using the same intestinal preparation in a future colonoscopy there was statistical significance in favor to SPMC (p = 0.026). Conclusions No differences were noted on effectiveness between the PEG and SPMC bowel preparations. Nevertheless, SPMC appeared to be better tolerated by patients.
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Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Compostos Organometálicos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Catárticos/administração & dosagem , Colonoscopia/métodos , Citratos/administração & dosagem , Picolinas/administração & dosagem , Cuidados Pré-Operatórios/métodos , Método Simples-Cego , Inquéritos e Questionários , Satisfação do PacienteRESUMO
We report an asymptomatic 23-year-old woman with an isolated and persistent increase in serum levels of aspartate aminotransferase (AST). An extensive work up including laboratory and image testing revealed no abnormalities thus suggesting the presence of macro-AST. A polyethylene glycol (PEG) precipitation assay was performed and confirmed the presence of macro-AST.
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Humanos , Feminino , Adulto Jovem , Aspartato Aminotransferases/sangue , Alanina Transaminase/sangue , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/enzimologia , Hepatopatias/diagnóstico , Hepatopatias/enzimologiaRESUMO
ABSTRACT Azithromycin is a water-insoluble drug, with a very low bioavailability. In order to increase the solubility and dissolution rate, and consequently increase the bioavailability of poorly-soluble drugs (such as azithromycin), various techniques can be applied. One of such techniques is "solid dispersion". This technique is frequently used to improve the dissolution rate of poorly water-soluble compounds. Owing to its low solubility and dissolution rate, azithromycin does not have a suitable bioavailability. Therefore, the main purpose of this investigation was to increase the solubility and dissolution rate of azithromycin by preparing its solid dispersion, using different Polyethylene glycols (PEG). Preparations of solid dispersions and physical mixtures of azithromycin were made using PEG 4000, 6000, 8000, 12000 and 20000 in various ratios, based on the solvent evaporation method. From the studied drug release profile, it was discovered that the dissolution rate of the physical mixture, as the well as the solid dispersions, were higher than those of the drug alone. There was no chemical incompatibility between the drug and polymer from the observed Infrared (IR) spectra. Drug-polymer interactions were also investigated using Differential Scanning Calorimetry (DSC), Powder X-Ray Diffraction (PXRD) and Scanning Election Microscopy (SEM). In conclusion, the dissolution rate and solubility of azithromycin were found to improve significantly, using hydrophilic carriers, especially PEG 6000.
RESUMO A azitromicina é um fármaco insolúvel em água, com biodisponibilidade muito baixa. A fim de aumentar a taxa de solubilidade e dissolução e, consequentemente, aumentar a biodisponibilidade de fármacos fracamente solúveis (tais como azitromicina), várias técnicas podem ser aplicadas. Uma dessas técnicas é a "dispersão sólida", frequentemente usada para melhorar a taxa de dissolução de compostos fracamente solúveis em água. Devido à baixa taxa de solubilidade e de dissolução, este fármaco não tem biodisponibilidade adequada. Portanto, o principal objetivo desta pesquisa foi o de aumentar a taxa de solubilidade e dissolução da azitromicina, preparando a sua dispersão sólida, utilizando diferentes glicóis de polietileno (PEG). As dispersões sólidas e as misturas físicas de azitromicina foram preparadas utilizando PEG 4000, 6000, 8000, 12000 e 20000, em várias proporções, com base no método de evaporação do solvente. O perfil de liberação do fármaco foi estudado e verificou-se que tanto a taxa de dissolução da mistura física quanto as dispersões sólidas foram maiores do que as do fármaco sozinho. Espectros de IR não revelaram incompatibilidade química entre o fármaco e o polímero. Interações fármaco-polímero também foram investigadas usando calorimetria diferencial de varredura (DSC), Difração de Raios X (PXRD) e Microscopia Eletrônica de Varredura(SEM). Em conclusão, a taxa de dissolução e a solubilidade da azitromicina melhoraram, de forma significativa, utilizando suportes hidrofílicos, especialmente PEG 6000.
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Azitromicina/análise , Azitromicina/farmacologia , Dissolução/métodos , Polietilenoglicóis/análise , Solubilidade/efeitos dos fármacosRESUMO
Background - Colonoscopy is an important diagnostic and therapeutic procedure. Adequate bowel preparation is mandatory. Several regimens were discussed in the literature. Among the drugs which has recently used, polyethylene glycol is one of the most popular agents. Objectives - The aim of this study was to compare efficacy of three different methods for 1 day preparation before colonoscopy. Methods - This study included children with the range of ages (2-21) who had an indication of colonoscopy. Exclusion criteria were based on the history of previous surgery, parental disagreement, and patients who did not use preparation protocol. Three methods for bowel preparation were studied: 1- Polyethylene glycol only; 2- Polyethylene glycol and bisacodyl suppositories; 3- Polyethylene glycol plus normal saline enema. Boston Bowel Preparation Score was used for evaluation of preparation. SPSS version 16.0 (Chicago, IL, USA) were used for data analysis. Results - In this study 83 cases completed the bowel preparation completely. Acceptable bowel preparation was seen in 24 (85.71%), 36 (94.73%), and 14 (82.35%) of cases in PEG, PEG + bisacodyl, and PEG + normal saline enema groups respectively. PEG + bisacodyl suppositories was more effective than PEG + normal saline for the preparation of the first segment ( P=0.05). For second and third segment of colon, BPPS score was higher in PEG + bisacodyl suppositories compared to other regimens, but this difference was not statistically significant. Conclusion - There was no significant difference between 1 day colonoscopy regimens in terms of bowel preparation score. Lowest score was seen in PEG + enema group compared to other group.
Contexto - A colonoscopia é um procedimento diagnóstico e terapêutico importante. A preparação intestinal adequada é obrigatória. Vários esquemas são discutidos na literatura. Dentre as drogas que se têm usado recentemente, o polietilenoglicol é um dos agentes mais utilizados. Objetivo - O objetivo deste estudo foi comparar a eficácia de três métodos diferentes para a preparação feita 1 dia antes de colonoscopia. Métodos - Este estudo incluiu crianças com a gama de idades entre 2 e 21 anos, que tinham indicação de colonoscopia. Os critérios de exclusão foram baseados em história da cirurgia anterior, não aprovação dos pais e pacientes que não utilizaram o protocolo de preparação. Três métodos para a preparação do intestino foram estudados: 1-polietilenoglicol; 2 - polietilenoglicol e bisacodil supositórios; 3 - polietilenoglicol e enema de solução salina. O escore de Boston para preparação intestinal foi usado para a avaliação e os dados foram analisados pelo SPSS versão 16.0 (Chicago, Il, USA). Resultados - Um total de 83 pacientes concluiu completamente o preparo intestinal. Houve preparo aceitável em 24 (85,71%), 36 (94,73%) e 14 (82,35%) dos casos, nos grupos PEG, PEG + bisacodil e PEG + enema salino, respectivamente. PEG + bisacodil supositórios foi mais eficaz do que a PEG + solução salina para a preparação do primeiro segmento ( P=0,05). Para segundo e terceiro segmento do cólon, a pontuação de BPPS foi maior no grupo PEG + bisacodil supositórios em comparação com outros regimes, mas essa diferença não foi estatisticamente significativa. Conclusão - Não houve nenhuma diferença significativa entre os regimes de preparo para colonoscopia de um dia em termos de pontuação de preparação do intestino. A nota mais baixa foi vista no grupo PEG + enema em comparação com outros grupos.
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Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Adulto Jovem , Bisacodil/administração & dosagem , Catárticos/administração & dosagem , Colonoscopia/métodos , Polietilenoglicóis/administração & dosagem , Cloreto de Sódio/administração & dosagem , Cooperação do Paciente , Irrigação Terapêutica/métodosRESUMO
PURPOSE: To evaluate of postoperative adhesion prevention and inflammatory response to polypropylene mesh, coated with reabsorbable hydrogel of polyethylene glycol (Coseal®) in contact with small bowel in an experimental model in rabbits. METHODS: Twenty female rabbits underwent laparotomy to implant two polypropylene meshes, 2x1cm, in the right and left flanks. The right mesh was protected with Coseal® spray (Group 1) and the left mesh received no treatment after implantation (Group 2). Thirty days after implantation, the rabbits underwent laparoscopy for adhesion analysis; the prosthesis were removed en bloc with the adjacent tissue for microscopic analysis of inflammation. Statistical analysis used the Mann-Whitney test. RESULTS: There was adhesion formation in five meshes (36%) from Group 1 and in 14 meshes (100%) from Group 2, with statistical significance (p<0.01). There were no differences in the inflammatory response, fibrosis, foreign body reaction, presence of collagen and type of inflammatory cells between the two groups. CONCLUSION: Polypropylene mesh coated with Coseal® showed a significantly lower rate of adhesion formation when compared with uncoated meshes, without interfering with inflammatory response.(AU)
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Animais , Coelhos , Hidrogéis/análise , Aderências Teciduais/complicações , Polipropilenos/análise , Coelhos/classificação , InflamaçãoRESUMO
PURPOSE: To evaluate of postoperative adhesion prevention and inflammatory response to polypropylene mesh, coated with reabsorbable hydrogel of polyethylene glycol (Coseal®) in contact with small bowel in an experimental model in rabbits. METHODS: Twenty female rabbits underwent laparotomy to implant two polypropylene meshes, 2x1cm, in the right and left flanks. The right mesh was protected with Coseal® spray (Group 1) and the left mesh received no treatment after implantation (Group 2). Thirty days after implantation, the rabbits underwent laparoscopy for adhesion analysis; the prosthesis were removed en bloc with the adjacent tissue for microscopic analysis of inflammation. Statistical analysis used the Mann-Whitney test. RESULTS: There was adhesion formation in five meshes (36%) from Group 1 and in 14 meshes (100%) from Group 2, with statistical significance (p<0.01). There were no differences in the inflammatory response, fibrosis, foreign body reaction, presence of collagen and type of inflammatory cells between the two groups. CONCLUSION: Polypropylene mesh coated with Coseal® showed a significantly lower rate of adhesion formation when compared with uncoated meshes, without interfering with inflammatory response.
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Animais , Feminino , Coelhos , Hérnia Abdominal/cirurgia , Polietilenoglicóis/efeitos adversos , Polipropilenos/uso terapêutico , Telas Cirúrgicas/efeitos adversos , Colágeno/análise , Modelos Animais de Doenças , Fibrose/patologia , Fibrose/prevenção & controle , Reação a Corpo Estranho/patologia , Reação a Corpo Estranho/prevenção & controle , Herniorrafia/métodos , Laparoscopia , Teste de Materiais , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/prevenção & controle , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento , Aderências Teciduais/patologia , Aderências Teciduais/prevenção & controleRESUMO
INTRODUÇÃO: As biopróteses valvares cardíacas estão relacionadas a eventos tromboembólicos, infecciosos e degenerativos. Seu desgaste é atribuído principalmente à desnaturação do colágeno. O glutaraldeído, método predominante de preservação de biopróteses, favorece o processo de calcificação e limita sua durabilidade. Diversas técnicas tentam conter o processo degenerativo das biopróteses. OBJETIVO: Avaliar o processo de calcificação, in vivo, de heteroenxertos pulmonares valvados, preservados em meio não-aldeídico (L-Hydro®). MÉTODOS: Dezessete carneiros foram submetidos à substituição do tronco da artéria pulmonar por enxerto tubular valvado de pericárdio bovino. Os animais foram distribuídos em dois grupos: Grupo L-Hydro® (teste / n=14) e Grupo Glutaraldeído (controle /n=3). Cerca de 150 dias pós-implante os animais foram sacrificados, necropsiados e as próteses submetidas a estudo anatomopatológico, avaliação radiológica e dosagem do cálcio por espectrofotometria de absorção atômica. A análise estatística foi obtida por meio dos testes exato de Fisher, T de Student ou Mann-Whitney (significância: 5%). RESULTADOS: A avaliação radiológica, macroscopia, microscopia e dosagem de cálcio por espectrofotometria de absorção atômica demonstraram maior calcificação nas próteses do Grupo Glutaraldeído, quando comparadas às próteses do Grupo L-Hydro® (P=0,001). Sete animais do Grupo L-Hydro® (50%) apresentaram aderência das cúspides à parede do tubo (P=0,228). CONCLUSÕES: As próteses preservadas em L-Hydro® demonstraram-se mais resistentes à calcificação, quando comparadas às preservadas em glutaraldeído.
INTRODUCTION: The cardiac bioprostheses are related to thromboembolic events, infectious and degenerative diseases. Wear is mainly attributed to the denaturation of collagen. Glutaraldehyde, the predominant method of preservation of bioprostheses, favors the calcification process and limits their durability. Several techniques try to contain the degenerative process of bioprostheses. OBJECTIVES: To evaluate the process of calcification in vivo pulmonary valve heterografts preserved in non-aldehydic (L-Hydro®). METHODS: Seventeen sheep underwent replacement of the pulmonary artery valved tubular grafts of bovine pericardium. The animals were divided into two groups: Group L-Hydro® (test / n = 14) and Group Glutaraldehyde (control / n = 3). About 150 days after implantation the animals were sacrificed, necropsied and implants subjected to a pathological study, radiological evaluation and measurement of calcium by atomic absorption spectrophotometry. Statistical analysis was obtained through the Fisher's exact test, Student's t or Mann-Whitney test (significance: 5%). RESULTS: The radiological evaluation, the macroscopic and microscopic measurement of serum calcium by atomic absorption spectrophotometry showed increased calcification of the prosthetic group Glutaraldehyde, when compared to denture-HydroR Group L (P = 0.001). Seven animals in Group L-Hydro® (50%) had adherence of the leaflets to the wall of the tube (P = 0.228). CONCLUSIONS: Prostheses preserved in L-Hydro® were more resistant to calcification when compared with glutaraldehyde preserved.
Assuntos
Animais , Bioprótese , Calcinose/fisiopatologia , Glutaral , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/métodos , Artéria Pulmonar/cirurgia , Valva Pulmonar/cirurgia , Calcinose/patologia , Cálcio/sangue , Desenho de Prótese , Falha de Prótese , Artéria Pulmonar/patologia , Artéria Pulmonar , Ovinos , Espectrofotometria Atômica , Fatores de TempoRESUMO
OBJETIVO: Buscando novas formas de preservação de tecidos utilizamos o polietileno-glicol, método L-Hydro (LH), que consiste na extração controlada de substâncias antigênicas e incorporação de agente antinflamatório e antitrombótico. MÉTODOS: Em dez carneiros jovens, substituímos o tronco pulmonar, em sete, por homoenxertos pulmonares (HP) tratados pelo processo L-H e, em três, por HP a fresco, implantados ortotopicamente, seguidos por 320 dias. Os carneiros foram avaliados por exames laboratoriais e ecocardiográficos. Ao cabo dos 320 dias foram sacrificados, procedendo-se à avaliação hemodinâmica, radiológica, macro/microscópica, óptica e eletrônica, varredura e transmissão. Resultados foram analisados pelo teste t de Student de amostras independentes para dados contínuos, análise de variância para medidas repetidas, pelo teste exato de Fisher para dados categóricos. RESULTADOS: Evolução clínica e exames laboratoriais não conseguiram estabelecer diferenças significativas entre os grupos. Ecocardiograma revelou diferença quanto ao gradiente médio pulmonar, significativa aos 10 meses, maior no grupo controle. Avaliação radiológica e macroscópica não estabeleceu diferenças. Na avaliação microscópica, óptica/eletrônica, células de revestimento e intersticiais foram encontradas nos dois grupos igualmente. O porcentual de revestimento celular calculado nos dois grupos foi semelhante. Nódulos de celularidade foram observados somente no grupo de homoenxertos a fresco. CONCLUSÕES: Estes dados indicam que os dois grupos apresentaram desempenho clínico e hemodinâmico semelhante. Ao ecocardiograma o grupo LH apresentou melhor desempenho, e evidências histológicas de repopulação celular intersticial e endotelial. Na análise macro/microscópica, óptica/eletrônica, o grupo L-Hydro apresentou macroscopia, estrutura histológica e ultraestrutural semelhante ao homoenxerto fresco, à exceção de nódulos de maior celularidade intersticial, presentes apenas no homoenxerto a fresco.
OBJECTIVE: In an effort to make available homografts preserved in a simpler and less costly way, we evaluated the polyethyleneglycol, L-Hydro (LH) method, that consists in the controlled extraction of antigenic substances and the incorporation of anti-inflammatory and anti-thrombotic agent. METHODS: We substituted the pulmonary trunk in ten ovines, seven received LH treated pulmonary homografts and three, fresh pulmonary homografts, orthotopically implanted and followed-up for 320 days. Ovines where evaluated by means of laboratory tests, echocardiographic exams. At the 320 days, were euthanized, hemodynamic, radiology, macroscopic, optic/electronic microscopic, scanning/transmission evaluations were performed. Results were analyzed by Student t test of independent samples for continuous data, by variance analysis of repeated measures, and by Fisher exact test for categorical data. RESULTS: We couldn't establish relevant differences in clinical evolution and laboratory tests between groups. Echocardiogram revealed difference in pulmonary medium gradient, which was significant 10 months follow-up, higher in the control group. Radiologic and macroscopic evaluations didn't established differences. In the optic/electronic microscopic evaluation, liner and interstitial cells were equally found in both groups. The cell liner percent calculated in both groups was similar. Cellularity nodules were observed only infresh homograft group. CONCLUSIONS: These data indicate that both groups presented similar clinical/hemodynamic performances. The LH group's echocardiogram presented a better performance. It also presented histological evidences of interstitial and endothelial cell repopulation. In the macro/optic and electronic microscopic analysis, group L-H presented macroscopy/histological structure and ultra-structural similar to the fresh group, with the exception of nodules with higher interstitial cellularity, present only in the fresh homograft group.
Assuntos
Animais , Valva Pulmonar/transplante , Preservação de Tecido/métodos , Criopreservação , Ecocardiografia , Hemodinâmica , Polietilenoglicóis , Valva Pulmonar/patologia , Valva Pulmonar/ultraestrutura , Ovinos , Transplante HomólogoRESUMO
In some situations, endodontic infections do not respond to therapeutic protocol. In these cases, it is suggested the administration of an alternative intracanal medication that presents a wide spectrum of action and has an in-depth effect on the root canal system. The purpose of this study was to assess the antimicrobial action of ciprofloxacin, metronidazole and polyethylene glycol and natrosol vehicles with different associations and concentrations. The minimum inhibitory concentration (MIC) was determined by using the agar dilution method. The culture media (Müller-Hinton agar) were prepared containing antimicrobial agents at multiple two-fold dilutions of 0.25 to 16 µg/mL, and with the vehicles at the concentrations of 50, 45, 40, 35, 30 and 25 percent. Twenty-three microbial strains were selected for the study. Metronidazole was not capable of eliminating any of the tested microorganisms. The association of ciprofloxacin with metronidazole resulted in a reduction of the MIC. The vehicle polyethylene glycol inhibited the growth of 100 percent of the tested strains, while natrosol inhibited 18 percent of the strains. Ciprofloxacin formulations with polyethylene glycol presented better effects than those of formulations to which metronidazole was added. It was possible to conclude that ciprofloxacin presented antimicrobial action against all tested bacterial strains, and its association with metronidazole was synergic. The vehicle polyethylene glycol showed antimicrobial effect and the ciprofloxacin/polyethylene glycol association was the most effective combination for reducing the tested bacteria and yeasts.