Effect of serum from patients with ST-segment elevation myocardial infarction on endothelial cells.

INTRODUCTION AND OBJECTIVES: Clinical and experimental studies have shown that, in patients with reperfused ST-segment elevation myocardial infarction (STEMI), abnormalities in the endothelial monolayer are initiated during ischemia but rapidly intensify upon restoration of blood perfusion to the ischemic area. We aimed to evaluate the effect of serum isolated after revascularization from STEMI patients on the degree of endothelial permeability in vitro, by promoting endothelial cell apoptosis and necrosis in vitro. We also investigated the association between the percentage of serum-induced endothelial cell apoptosis or necrosis in vitro and the extent of cardiovascular magnetic resonance (CMR)-derived parameters of reperfusion injury (edema, hemorrhage, and microvascular obstruction). METHODS: Human coronary artery endothelial cells were incubated with serum isolated 24hours after revascularization from 43 STEMI patients who underwent CMR and 14 control participants. We assessed the effect of STEMI serum on activation of apoptosis and necrosis, as well as on the permeability and structure of the endothelial monolayer. RESULTS: Serum from STEMI patients increased apoptosis (P <.01) and necrosis (P <.05) in human coronary artery endothelial cells and caused increased permeability of the endothelial monolayer in vitro (P <.01), due to enlarged intercellular spaces (P <.05 vs control in all cases). Higher serum-induced necrosis was associated with greater endothelial permeability in vitro (P <.05) and with more extensive CMR-derived indices of reperfusion injury and infarct size. CONCLUSIONS: Postreperfusion serum activates necrosis and apoptosis in endothelial cells and increases the degree of endothelial permeability in vitro. The more potent the necrosis-triggering effect of serum, the more deleterious the consequences in terms of the resulting cardiac structure.

Análisis bidimensional de la permeabilidad de vías aéreas con el tamaño de senos maxilares y su relación con el desarrollo de la clase esqueletal en una población mexicana / Two-dimensional analysis of airway permeability with maxillary sinus size and its relationship with the development of skeletal class in a Mexican population

Comparar la permeabilidad de las vías aéreas y el tamaño de los senos maxilares en relación con la clase esqueletal. se midieron 90 radiografías lateral de cráneo, divididas en 3 grupos, comparando las 3 clases esqueletales, las cuales se determinaron con la medida ANB de Steiner, y estas a su vez en dos subgrupos que fueron hombres y mujeres, en las cuales se utilizó el análisis de McNamara para el análisis de vías aéreas y para el área del seno maxilar se tomaron dos medidas una antero-posterior y cefálica-caudal. Al comparar los hombres con las mujeres se identificó significancia estadística en vía área superior de clase II (p=≤0.017), vía aérea inferior de clase III (p=≤0.006). Al comparar las clases esqueletales en hombres se identificó diferencias en la vía aérea superior en las clases I vs III (p=≤0.05), inferior en la clase I vs III (p=≤0,001) y II vs III (p=≤0.044). Con respecto a mujeres se identificó significancia en la vía aérea superior al comparar la clase I vs II (p=≤0,043), vía aérea inferior en la clase II vs III (p=≤0.05), longitud del seno maxilar al comparar clase I vs II (p=≤0.017). Entre la clase I esqueletal y la clase II, el tamaño de los senos maxilares resulto menor en longitud en las mujeres de clase II esqueletal. Entre la clase I y clase III esqueletal en hombres, se encontró una longitud menor en la vía aérea superior e inferior en la clase I. Las vías aéreas resultaron en menor tamaño en sujetos de clase II.

SUMMARY: To compare the airway permeability and the size of the maxillary sinuses in relation to the skeletal class. 90 lateral skull radiographs were divided into 3 groups, comparing the 3 skeletal classes, which were determined with Steiner's ANB measurement, and these were once in two subgroups that were men and women, in any McNamara analysis was used for the analysis of airways and for the maxillary sinus area measurements were made an antero-posterior and cephalic-caudal. When comparing males with females, statistical significance was identified in the upper class II route (p=≤0,017), lower class III airway (p=≤0.006). At least skeletal classes in men, differences were identified in the upper airway in classes I vs III (p=≤0.05), lower in class I vs III (p=≤0.001) and II vs III (p=≤0.044). With respect to women, significance was identified in the upper airway when comparing class I vs II (p=≤0.043), lower airway in class II vs. III (p=≤0.05), maxillary sinus length to class I vs II (p=≤0.017). Between skeletal class I and class II, maxillary sinus size was shorter in length in skeletal class II women. Between class I and skeletal class III in men, a lower length was found in the upper and lower airways in class I. The airways were found to be smaller in class II subjects.

La vitamina C, implicaciones terapéuticas en el paciente con quemaduras graves / Vitamin C, therapeutic implications in the patient with serious burns / Vitamina C, implicações terapêuticas no paciente com queimaduras graves

Resumen: La atención a pacientes con quemaduras extensas es compleja, la quemadura condiciona efectos en el sitio de la lesión y a nivel sistémico. A nivel de la microcirculación se presenta respuesta de mediadores químicos inflamatorios y excesiva producción de especies reactivas de oxígeno y nitrógeno, además condiciona disminución de la capacidad antioxidante de vitamina C, por lo que se altera el balance fisiológico de óxido-reducción, dando paso al estado de estrés oxidativo, esto trae como consecuencia un incremento en la inflamación, disfunción endotelial e incremento de la permeabilidad capilar. Uno de los objetivos de la reanimación del paciente quemado es restaurar el volumen intravascular generado por el estado de choque, en el cual se implementan estrategias como el uso de cristaloides, coloides, plasma, terapias dialíticas, uso limitado de opioides y la administración de vitamina C. El objetivo de este trabajo es dar a conocer a la comunidad médica las características físicas y químicas, los mecanismos moleculares de la vitamina C en los que se encuentra implicada en condiciones de quemaduras graves, con la finalidad de la implementación durante la fase de reanimación del quemado.

Abstract: The care of patients with extensive burns is complex, the burn conditions effects at the site of the injury and at the systemic level. At the microcirculation level, there is a response of inflammatory chemical mediators and excessive production of reactive oxygen and nitrogen species, which also causes a decrease in the antioxidant capacity of vitamin C, which is why the physiological balance of oxide-reduction is altered, giving way to the state of oxidative stress, this results in an increase in inflammation, endothelial dysfunction and an increase in capillary permeability. One of the objectives of the resuscitation of the burned patient is to restore the intravascular volume generated by the state of shock, in which strategies such as the use of crystalloids, colloids, plasma, dialysis therapies, limited use of opioids and the administration of vitamins are implemented C. The objective of this work is to make known to the medical community, the physical and chemical characteristics, the molecular mechanisms of vitamin C in which it is involved in severe burn conditions, with the purpose of implementation during the resuscitation phase of burn.

Resumo: O atendimento a pacientes com queimaduras extensas é complexo, a queimadura condiciona efeitos no local da lesão e em nível sistêmico. Ao nível da microcirculação, há uma resposta de mediadores químicos inflamatórios e produção excessiva de espécies reativas de oxigénio e nitrogênio, condiciona também uma diminuição da capacidade antioxidante da vitamina C, que altera o equilíbrio fisiológico de oxidação-redução, dando lugar a o estado de estresse oxidativo, isso resulta em aumento da inflamação, disfunção endotelial e aumento da permeabilidade capilar. Um dos objetivos da ressuscitação do paciente queimado é restaurar o volume intravascular gerado pelo estado de choque, no qual se implementam estratégias como o uso de cristalóides, colóides, plasma, terapias dialíticas, uso limitado de opióides e administração de vitamina C. O objetivo deste trabalho é dar a conhecer à comunidade médica as características físicas e químicas, os mecanismos moleculares da vitamina C em que está envolvida em condições de queimaduras graves, com vista à sua aplicação durante a fase de reanimação do paciente queimado.

Microbiota intestinal en la salud humana / Gut microbiota in human health

Introducción: La microbiota describe a un grupo de microorganismos en una región o período de tiempo que incluye: bacterias, arqueas, protistas, hongos y virus. Objetivos: Explicar la función de la microbiota intestinal en la salud humana. Métodos: Se realizó una búsqueda en diferentes de bases de datos como NHI, Ebsco y PubMed en idioma español e inglés, se revisó un total de 17 artículos de los cuales el mayor por ciento es de menos de 5 años. Resultados: Las microbiota intestinal en su mayoría se compone de Gram negativa, con una pared celular rica en lipopolisacáridos (LPS) que potencia a la inmunidad innata por interacción de receptor Toll-like (TLR) ligando, desencadena la producción de citoquinas proinflamatorias, entre otros. Conclusiones: La microbiota intestinal funciona como un señalizador antiinflamatorio y regulador de la permeabilidad epitelial intestinal(AU)

Introduction: Microbiota describes a group of microorganisms in a region or period of time that includes bacteria, archaea, protists, fungi, and viruses. Objectives: To explain the role of the intestinal microbiota in human health. Methods: A search was carried out in different databases such as NHI, Ebsco and PubMed in Spanish and English, a total of 17 articles were reviewed, most of them are less than 5 years. Results: Intestinal microbiota is mostly composed of Gram negative, with a cell wall rich in lipopolysaccharides (LPS) that enhances innate immunity by Toll-like receptor (TLR) ligand interaction, triggers the production of proinflammatory cytokines, among others. Conclusions: Intestinal microbiota functions as an anti-inflammatory signaling agent and regulator of intestinal epithelial permeability(AU)

Efetividade do ácido ascórbico e solução fisiológica no acesso venoso central pediátrico: ensaio clínico randomizado / Effectiveness of ascorbic acid and saline solution in pediatric central venous access: randomized clinical trial / Efectividad del ácido ascórbico y la solución salina en el acceso venoso central pediátrico: ensayo clínico aleatorizado

RESUMO Objetivo: comparar a efetividade entre o uso de ácido ascórbico e solução fisiológica 0,9% na prevenção de obstrução de cateter venoso central pediátrico. Método: ensaio clínico randomizado realizado em Hospital Público do Paraná, entre os meses de junho de 2018 a outubro de 2019 com 152 participantes, dos quais, 73 do grupo experimental e 79, grupo-controle) que foram submetidos à inserção de cateter venoso central e randomizados para receber a intervenção flush com ácido ascórbico ou solução fisiológica 0,9%. Resultados: obstrução do cateter ocorreu em 17 casos (11,2%), sendo nove (11,4%) no grupo- controle e oito (10,9%) no grupo experimental. Obstrução trombótica ocorreu em 15 casos, de forma semelhante, nos dois grupos (p=0,88). A remoção do cateter ocorreu em 82 casos por questões eletivas e, em 63 casos, por complicações. Conclusão: o uso de ácido ascórbico é tão eficiente quanto a solução fisiológica a 0,9% na prevenção da obstrução de cateter venoso central. O estudo amplia as possibilidades de intervenções dentro da temática.

ABSTRACT Objective: to compare the effectiveness between the use of ascorbic acid and 0.9% saline solution in the prevention of pediatric central venous catheter obstruction. Method: randomized clinical trial conducted in a public hospital in Paraná, between the months of June 2018 to October 2019 with 152 participants, of which, 73 in the experimental group and 79, control group) who underwent central venous catheter insertion and randomized to receive the flush intervention with ascorbic acid or 0.9% saline solution. Results: Catheter obstruction occurred in 17 cases (11.2%), nine (11.4%) in the control group and eight (10.9%) in the experimental group. Thrombotic obstruction occurred in 15 cases, in a similar way, in both groups (p=0.88). Catheter removal occurred in 82 cases for elective reasons and in 63 cases for complications. Conclusion: the use of ascorbic acid is as efficient as 0.9% saline solution in preventing central venous catheter obstruction. The study expands the possibilities of interventions within the theme.

RESUMEN Objetivo: comparar la efectividad del ácido ascórbico y la solución salina al 0,9% en la prevención de la obstrucción del catéter venoso central pediátrico. Método: ensayo clínico aleatorizado realizado en un hospital público de Paraná, entre los meses de junio de 2018 a octubre de 2019 con 152 participantes, de los cuales, 73 en el grupo experimental y 79, grupo control) que fueron sometidos a la inserción de catéteres venosos centrales y aleatorizados a recibir la intervención de lavado con ácido ascórbico o solución salina al 0,9%. Resultados: la obstrucción del catéter se produjo en 17 casos (11,2%), nueve (11,4%) en el grupo de control y ocho (10,9%) en el grupo experimental. La obstrucción trombótica se produjo en 15 casos, de forma similar, en ambos grupos (p=0,88). La retirada del catéter se produjo en 82 casos por razones electivas y en 63 casos por complicaciones. Conclusión: el uso de ácido ascórbico es tan eficiente como la solución fisiológica al 0,9% en la prevención de la obstrucción del catéter venoso central. El estudio amplía las posibilidades de intervención dentro del tema.

Polimorfismo rs2291166 del gen TJP1 como marcador en estadios tempranos de nefropatía en pacientes con Diabetes Mellitus Tipo 2 / rs2291166 TJP1 polymorphism as a marker in early stages of nephropathy in patients with Type 2 Diabetes Mellitus

RESUMEN Objetivo: Analizar la asociación entre el polimorfismo rs2291166 del gen TJP1 con los niveles de glucosaminoglucanos (GAGS) excretados en orina como marcador de las primeras etapas de la nefropatía. Material y métodos: Se analizaron 600 muestras de orina de sujetos recién diagnosticados con diabetes tipo 2, de las cuales se incluyeron 203. La detección de GAGS en orina directa se realizó mediante prueba de turbidez de albúmina ácida y precipitación con cetilpiridinio (CPC). Resultados: El 26,64% de los pacientes diabéticos se encuentran en estadios tempranos de nefropatía, lo que corresponde a pacientes con prueba GAG positiva, siendo los que tienen mayor excreción de GAGS, heterocigotos para el polimorfismo. Conclusión:Sugerimos que el polimorfismo de TJP1 rs2291166 influye en la mucopolisacariduria en pacientes diabéticos tipo 2 de la población mexicana; que podría usarse como un marcador genético/ bioquímico válido para las primeras etapas de la nefropatía diabética.

ABSTRACT Objective: To analyze the association between the polymorphism rs2291166 of TJP1 gene, with the urine-excreted levels of GAGS as a marker of early stages of nephropathy. Methods: A 600 urine samples from newly diagnosed subjects with type 2 diabetes were analyzed, of which 203 were included. The GAGS detection in direct urine (corresponding to the first urine of the morning), was performed by albumin turbidity test and precipitation with cetylpyridinium (CPC). Results: The present study shows that 26.64% of diabetic patients are in early stages of nephropathy, corresponding to patients with a positive GAG test, being those with the highest GAGS excretion, heterozygous for the polymorphism. Conclusion: We suggest that the TJP1 polymorphism rs2291166 influences mucopolysacchariduria in type 2 diabetic patients of the Mexican population, which could be used as a valid genetic/biochemical marker for the early stages of diabetic nephropathy.

Efecto del pH sobre propiedades mecánicas, fisicoquímicas y morfológicas en películas comestibles multicomponentes / Effect of pH on mechanical, physicochemical and morphological properties in multicomponent edible films

RESUMEN El pH es un parámetro fundamental a considerarse en el momento de diseñar películas multicomponentes, debido a que interviene en la compatibilidad e interacciones que se generan entre los componentes de la matriz, determina la funcionalidad de las mismas y como se demuestra en este estudio, el pH tiene una influencia significativa en las propiedades mecánicas, fisicoquímicas y morfologías de las películas. Con ese objetivo, se sometieron películas a base de goma gellan, gelatina, caseinato de calcio, aceite de canola, glicerol, tween 80 y natamisina, a cuatro niveles de pH T1:6,6 T2:6,2 T3:5,8 T4:5,4 para evaluar y determinar la influencia del pH en las propiedades finales de las películas. Como resultado obtenido en las propiedades, se presentaron diferencias significativas (α=0,05), influenciadas por la modificación del pH, de modo que, en las películas sometidas a un pH de T4=5,4 se generó una mejor compatibilidad de los componentes, por las condiciones del medio que permitieron obtener interacciones por fuerzas electrostáticas entre los polímeros y el aceite, evidenciándose en el mejor comportamiento mecánico con una elongación de 10,6 ± 1,8%, mayor permeabilidad al vapor de agua, solubilidad de 51 ± 0,02% y un contenido de humedad de 9 ± 3,0%; a diferencia de las películas de T1, en las cuales, predominaron las interacciones a través de los enlaces de hidrógeno, afectando la permeabilidad y el comportamiento mecánico de las mismas. En películas multicomponentes a base polímeros y lípidos para garantizar mayor compatibilidad e interacciones que se reflejan en mejores propiedades mecánicas, fisicoquímicas y morfológicas entre los componentes se deben elaborar películas a pH de 5,4 o, en caso contrario, en los cuales, las propiedades deban permitir mayores interacciones entre grupos polares de los componentes utilizar pH más básicos, como pH de 6,6.

ABSTRACT pH is a fundamental parameter to be considered when designing multicomponent films, because it intervenes in the compatibility and interactions that are generated between the components of the matrix, determines their functionality and as demonstrated in this study the pH has a significant influence on the mechanical, physicochemical and morphological properties of films. With this objective, films based on gellan gum, gelatin, calcium caseinate and canola oil were subjected to four levels of pH T1 = 6.6 T2 = 6.2 T3 = 5.8 T4 = 5.4 to evaluate and determine the influence of pH on the final properties of the films. As a result obtained in the properties there were significant differences (α = 0.05) influenced by the modification of the pH so that in the films subjected to a pH of T4 = 5.4 a better compatibility of the components was generated by the conditions of the medium that allowed to obtain interactions by electrostatic forces between the polymers and the oil, being evident in the best mechanical behavior with an elongation of 10.6 ± 1.8%, greater water vapor permeability, solubility of 51 ± 0.02% and a moisture content of 9 ± 3.0%; unlike the T1 films in which the interactions through hydrogen bonds predominated, affecting their permeability and mechanical behavior. Finally, as a conclusion in multi-component films based on polymers and lipids to ensure greater compatibility and interactions that are reflected in better mechanical, physicochemical and morphological properties between the components, films at pH 5.4 or otherwise in the which properties should allow greater interactions between polar groups of the components to use more basic pH such as pH 6.6.

Efecto del EDTAC y del ácido cítrico sobre la pared dentinaria. Variación del tiempo de exposición y la edad dentaria / Effect of EDTAC and citric acid on dentinal walls. Variation of exposure time and dental age

The aim of this study was to find a formula and application time for chelators effective in cleaning the root canal without causing erosion and considering dental age. The sample included 120 teeth: 60 taken from young patients and 60 from adult patients. They were instrumented and irrigated with 2.5% sodium hypochlorite (NaOCl). Each subgroup was divided randomly into six groups: 4 groups of 12 teeth and 2 control groups of 6 teeth. In the final irrigation, 17% ethylenediaminetetraacetic acid plus Cetavlón (EDTAC) or 10% citric acid was applied for 1 or 3 minutes according to each group. The results showed a high level of cleanliness, and a few showed erosion of the dentinal tubules. Satisfactory results were obtained in the removal of the smear layer when applying EDTAC or citric acid combined with NaOCl. Erosion was present in different degrees regardless of dental age, but it was indeed affected by the irrigant exposure time.

O objetivo deste estudo foi obter uma fórmula e um tempo de aplicação dos quelantes efetivos que permitam a limpeza das paredes do canal sem causar erosões, levando em consideração a idade dental. A amostra foi composta por 120 dentes, 60 de pacientes jovens e 60 de pacientes adultos, foram instrumentados e irrigados com hipoclorito de sódio (NaOCl) a 2,5%. Cada subgrupo foi dividido aleatoriamente em 6 grupos: 4 grupos de 12 dentes e 2 grupos de controle com 6 dentes cada um. Na irrigação final, ácido etilenodiaminotetracético com Cetavlón (EDTAC) 17% ou ácido cítrico 10% foi aplicado por 1 ou 3 minutos, dependendo do grupo. Os resultados mostraram um bom nível de limpeza com algumas amostras com erosão dos túbulos dentinários. Com EDTAC ou ácido cítrico combinado com NaOCl, resultados satisfatórios foram obtidos na remoção da camada de esfregaço . A erosão esteve presente em seus diferentes graus independentemente da idade dentária, mas não do tempo de exposição do irrigante.

Manutenção da permeabilidade dos dispositivos de acesso venoso central em pacientes com câncer / Maintenance of central venous access devices permeability in cancer patients / Mantenimiento de la permeabilidad de los dispositivos de acceso venoso central en pacientes con câncer

Objetivo: atualizar o conhecimento sobre a manutenção da permeabilidade dos Dispositivos de Acesso Vascular Central (DAVC) em paciente com câncer. Conteúdo: os pacientes que fazem uso de quimioterápicos muitas vezes necessitam de DAVC seguros e de longa permanência; a obstrução ocorre em 36% dos pacientes com DAVC inseridos no período de 2 anos, que pode ser classificada como mecânica, por precipitação de medicamento/minerais e pela formação de coágulos. A equipe de enfermagem é responsável por realizar os cuidados para manter a permeabilidade desses dispositivos através do Flushing e Locking. O uso de heparina demonstrou baixa evidência quando comparado ao Soro Fisiológico (SF), em relação a diminuição da obstrução. Conclusão: o uso de SF na manutenção dos DAVC mostra-se seguro, eficaz e com menor custo financeiro.

Objective: to update the knowledge on the maintenance of permeability of Central Vascular Access Devices (CVAD) in cancer patients. Content: Patients on chemotherapy often require safe, long-term CKD. Obstruction occurs in 36% of patients with CVAD inserted in a 2-year period, which can be classified as mechanical due to drug / mineral precipitation and clot formation. The nursing staff is responsible for taking care to maintain the permeability of these devices through Flushing and Locking. The use of heparin showed low evidence when compared to saline (SF), regarding the reduction of obstruction. Conclusion: the use of DES to maintain CVAD is safe, effective and has a lower financial cost.

Objetivo: actualizar los conocimientos sobre el mantenimiento de la permeabilidad del dispositivo de acceso vascular central (DAVC) en pacientes con cáncer. Contenido: los pacientes que usan quimioterápicos a menudo necesitan DAVC seguros y de larga permanência. La obstrucción ocurre en el 36% de los pacientes con DAVC insertados en el período de 2 años y puede ocorir por precipitación de medicamento / minerales y por la formación de coágulos. El equipo de enfermería es responsable de realizar los cuidados para mantener la permeabilidad de estos dispositivos a través del Flushing y Locking. El uso de heparina demostró una baja evidencia en comparación con el Suero Fisiológico (SF), en relación con la disminución de la obstrucción. Conclusión: el uso de SF en el mantenimiento de los DAVC se muestra seguros, eficaz y con menor costo financiero.

Efecto de la aplicación activa con aplicadores mejorados de un adhesivo universal / Effect of the active application of a universal adhesive with improved applicators

RESUMEN Introducción: La permeabilidad dentinaria es conocida como el paso de fluidos, iones, partículas, moléculas y bacterias a través de la dentina bajo ciertas condiciones. Objetivo: Determinar la influencia de la aplicación activa con un aplicador mejorado de un adhesivo dentinario sobre la conductancia hidráulica dentinaria humana, in vitro. Métodos: Estudio experimental in vitro en 40 terceros molares libres de caries, con indicación de exodoncia, provenientes de pacientes sanos entre 15 y 30 años, previo consentimiento informado. Posteriormente se limpiaron, desinfectaron y conservaron para ser incluidos en bloques de resina epóxica. Luego se realizaron cortes transversales y se obtuvieron discos dentinarios de 1,5 mm de espesor y 25 mm de diámetro. Se dividieron en dos grupos de 20 unidades cada uno, se sometieron a grabado con ácido ortofosfórico al 37 por ciento, y se lavaron y secaron. Sobre una balanza de precisión se les aplicó adhesivo dentinario fotopolimerizable, registrando la fuerza ejercida. En el grupo 1 se usó un microbrush en la aplicación y en el grupo 2 un aplicador mejorado diseñado especialmente. Posteriormente cada muestra fue sometida a una cámara de difusión para obtener la tasa de flujo y luego calcular la conductancia hidráulica, la cual otorga información acerca de la permeabilidad de la dentina. Resultados: los resultados obtenidos fueron levemente menores en el grupo 2, sin embargo, experimentaron una distribución normal. Conclusiones: no existen diferencias significativas, al ser analizados estadísticamente bajo diversas pruebas, en los valores de conductancia hidráulica. Tampoco se pudo establecer una relación inversa entre la fuerza de aplicación de un adhesivo en forma activa con un aplicador mejorado y la conductancia hidráulica, por lo cual no se aconseja el uso de dicho instrumento(AU)

ABSTRACT Introduction: Dentin permeability is defined as the passage of fluids, ions, particles, molecules and bacteria through the dentin under certain conditions. Objective: Determine the effect of the active application of a dentin adhesive with an improved applicator on human dentin hydraulic conductance in vitro. Methods: An in vitro experimental study was conducted of 40 caries-free third molars with an indication of exodontia from healthy patients aged 15-30 years, prior informed consent. The molars were cleaned, disinfected and preserved to be included in epoxy resin blocks. Cross-sectional cuts were then made to obtain dentin discs 1.5 mm thick and 25 mm in diameter. These were divided into two 20-unit groups, were subjected to etching with 37 percent orthophosphoric acid, and were washed and dried. On a precision scale photopolymerizable dentin adhesive was applied, recording the force exerted. Application was performed with a Microbrush applicator in Group 1 and with an improved dedicated applicator in Group 2. The samples were then placed in a diffusion chamber to determine flow rate and subsequently estimate hydraulic conductance, thus obtaining information about dentin permeability. Results: Results were slightly lower in Group 2, but they displayed normal distribution. Conclusions: Statistical analysis with various tests did not find any significant differences in hydraulic conductance values, nor could an inverse relation be established between the force of active application of an adhesive with an improved applicator and hydraulic conductance. Therefore, use of that instrument is not advised(AU)

Utility of doppler ultrasound in the preoperative evaluation of the first vascular access for haemodialysis. / Utilidad de la valoración ecográfica previa a la realización del primer acceso vascular para hemodiálisis.

INTRODUCTION: Traditionally, the indication of the type of vascular access (VA) has been based on the surgeon's physical examination, but it is now suggested that imaging methods could provide a clinical benefit. Our aim was to determine whether or not preoperative Doppler ultrasound modifies outcomes of the first VA for haemodialysis. PATIENTS AND METHODS: Prospective cohort of patients undergoing a first VA from June 2014 to July 2017 who had a preoperative Doppler ultrasound (ECO group). They were compared to a historical cohort (January 2012-May 2014) of first VA indicated exclusively by clinical assessment (CLN group). RESULTS: A total of 86 patients from the CLN group were compared to 92 from the ECO group, which was younger (68.4 vs 64.0, P=.038). The primary patency (CLN/ECO) at 1 and 2years was 59.5%/71.9% and 53.1%/57.8% respectively, marginally better in the ECO group (P=.057). The assisted patency at 1 and 2years was 63.2%/80.7% and 58.1%/70.2%, respectively, significantly better for the ECO group (P=.010). Due to lack of patency/utility of the initial VA, 26.7% in the CLN group and 7.6% in the ECO group (P<.001) required a new VA during the first 6months. An average of 1.39 interventions were performed to achieve a useful VA in the CLN group and 1.08 in the ECO group (P<.001), the first VA being useful at the radiocephalic level in 31.0%/45.1% (P=.039). CONCLUSION: The indication of the first VA according to a preoperative Doppler ultrasound examination could decrease the need for new VA, enable them to be made more distal, and significantly improve patency.

Determinación de la presencia de Escherichia coli en la cáscara y parte comestible del banano y evaluación de su crecimiento durante el proceso de postcosecha y almacenamiento a temperatura controlada / Determination of the presence of Escherichia coli in the peel and edible part of the banana and evaluation of its growth during the post-harvest process and storage at controlled temperature

Ante la necesidad de garantizar alimentos inocuos para los consumidores, las agroindustrias han implementado prácticas preventivas y desarrollado investigación que respalde sus procesos. El gremio productor de banano en Guatemala precisó determinar la presencia de Escherichia coli en la cáscara y parte comestible de la fruta, y el crecimiento de esta bacteria durante la postcosecha y almacenamiento. El estudio se realizó en cuatro plantas empacadoras de banano en Guatemala con dos objetivos: el primero determinar si la bacteria E. coli logra infiltrarse hacia la parte comestible del banano durante el lavado postcosecha, y el segundo, determinar si existe presencia de E. coli en la cáscara del banano en estiba y en simulación de almacenamiento a temperatura controlada. Para el primer objetivo se recolectaron al azar dos cajas de banano de una empacadora, que fueron trasladadas al laboratorio donde se replicaron las condiciones de la pileta de lavado y se introdujo E. coli de manera intencional; posteriormente, se utilizó el método de número más probable, para analizar el macerado de la fruta. Para el segundo objetivo, se recolectaron al azar cinco cajas de banano provenientes de tres empacadoras, se realizaron muestreos en la cáscara de dos bananos por caja, tanto en estiba, como durante el almacenamiento a temperaturas entre 17 y 18 °C, los días 4 y 18. Los resultados indicaron ausencia de E. coli en la parte comestible de la fruta y en la cáscara del banano durante el proceso de estiba y almacenamiento en los tiempos evaluados

To ensure innocuous food for consumers, agroindustries have implemented preventive practices and have developed research that supports their processes. e banana producing guild in Guatemala required to determine the presence of Escherichia coli in the peel and edible part of the fruit, and to determine the growth of this bacteria during postharvest and storage processes. e study was carried out in four banana packing plants in Guatemala with two objectives; the first one was to determine if E. coli is able to infiltrate the edible part of the banana during postharvest washing. e second objective was to determine if there is E. coli in the banana peel at stowage and in simulation of controlled temperature storage. For the first objective, two boxes of banana were randomly collected from a packing line, then were transferred to the laboratory where the conditions of the washing tank were replicated and E. coli was introduced intentionally. e most probable number method was used to analyze the maceration of the fruit. For the second objective, five boxes of bananas were randomly collected from three packing plants. Samplings were made to the peel of two bananas per box, at stowage, and then during storage at temperatures between 17 and 18° C, during the 4th and 18th day. e results indicated absence of E. coli in the edible part of the fruit and in the banana peel at stowage area, and at controlled storage temperature during the evaluation time

Tipos de cirugías arteriales en pacientes diabéticos / Types of arterial surgeries in diabetic patients

Introducción: Las cirugías arteriales en los pacientes diabéticos permiten disminuir las frecuencias de amputaciones que se realizan en estos pacientes. Objetivo: Exponer los principales tipos de cirugías arteriales en los miembros inferiores que se realizan en pacientes diabéticos y sus resultados. Métodos: Estudio de búsqueda y síntesis bibliográfica en el que consultaron y tamizaron 162 documentos (artículos, registros médicos y tesis) publicados en las bases de datos de sistemas referativos MEDLINE, PubMed y SciELO e indexadas en la Web of Sciencies, Scopus, Redalyc y Latindex, con la utilización de descriptores: cirugía revascularizadora, permeabilidad arterial, pie diabético, cirugía endovascular, endarterectomía, angioplastia transluminal percutánea. Esto generó que se seleccionara 43 artículos y tres registros médicos. Resultados: La técnica en la revascularización del sector aortoiliaco incluye la cirugía derivativa anatómica [by-passaorto-femoral (bi o uni)]y la extraanatómica [by-pass (axilo-femoral, fémoro-femoral), la endarterectomía y la cirugía endovascular en el sector iliaco. Las técnicas quirúrgicas a aplicar en el sector femoropoplíteo y distal son el by-pass secuencial, endarterectomía, simpatectomía, tratamiento endovascular. Es importante tener en cuenta las características de los pacientes por separado para la decisión del tipo de cirugía. Conclusiones: Las cirugías arteriales en el paciente diabético son diversas y para su éxito es necesario valorar siempre el riesgo quirúrgico y la anatomía de las lesiones de cada paciente(AU)

Introduction: Arterial surgeries in diabetic patients allow reducing the frequency of amputations that are performed in these patients. Objective: To show the main types of arterial surgery in the lower limbs performed in diabetic patients and their results. Methods: Bibliographic search and synthesis study in which 162 materials (articles, medical records and theses) published in the MEDLINE, PubMed and SciELO reference databases were searched and indexed in the Web of Sciencies, Scopus, Redalyc and Latindex, using as descriptors: revascularization surgery, arterial permeability, diabetic foot, endovascular surgery, endarterectomy, percutaneous transluminal angioplasty. This led to the quoting of 43 articles and three medical records. Results: The technique in the revascularization of the aorto iliac sector includes the anatomical derivative surgery [aorto-femoral by-pass (bi or uni)] and extra-anatomical [by-pass (axillo-femoral, femoro-femoral), endarterectomy and endovascular surgery in the iliac sector. The surgical techniques to be applied in the femoro popliteal and distal sectors are the sequential by-pass, endarterectomy, sympathectomy, and endovascular treatment. It is important to consider the characteristics of patients separately to decide the type of surgery. Conclusions: The arterial surgeries in the diabetic patient are diverse and for the success of them it is necessary to always assess the surgical risk and the anatomy of the lesions of each patient(AU)

Efectividad de la cirugía arterial en pacientes diabéticos en un período de cinco años / Effectiveness of arterial surgery in diabetic patients over a period of five years

Introducción: La macroangiopatía diabética constituye un serio problema para los pacientes que la portan y la cirugía revascularizadora constituye una alternativa de tratamiento. Objetivo: Demostrar la efectividad de las cirugías arteriales realizadas en pacientes diabéticos en un período de cinco años. Métodos: Estudio descriptivo, retrospectivo, en 71 historias clínicas de pacientes portadores de macroangiopatía diabética que recibieron cirugía arterial en el Instituto Nacional de Angiología y Cirugía Vascular (enero/2011- diciembre/2015). Se analizaron las variables: edad, género, color de la piel, supervivencia de la extremidad, estado de permeabilidad de los injertos y frecuencia de fallecimientos, que en su conjunto medirán la efectividad de la cirugía. Resultados: Hubo un incremento lineal de las cirugías revascularizadoras. La edad media fue de 64,5 ± 9,7 años, con un 67,6 por ciento de mayores de 60 años y más del 60 por ciento eran hombres. El 52,9 por ciento tenía piel blanca, el 80,3 por ciento tuvo grado 4 según Fontaine y el 66,2 por ciento tenía oclusión arterial severa. En más del 90 por ciento se realizó cirugía derivativa o endarterectomía, el 87,3 por ciento tuvo afectado el sector infrainguinal y en el 64,8 por ciento sobrevivió la extremidad. No se registraron muertes perioperatorias ni fallecidos a los seis meses. El 63 por ciento de las cirugías fueron permeables a los seis meses. Conclusiones: Las cirugías arteriales son efectivas pues la mayoría de los pacientes mantienen la extremidad afectada y no se registran fallecimientos perioperatorios ni a los seis meses de evaluación, además, la mayor cantidad de injertos resultaron ser permeables en ese tiempo(AU)

Introduction: Diabetic macroangiopathy is a serious problem for patients who suffer it; and revascularization surgery is an alternative to its treatment. Objective: To show the effectiveness of arterial surgeries performed in diabetic patients over a period of five years. Methods: Descriptive, retrospective study in 71 clinical records of patients with diabetic macroangiopathy who received arterial surgery at the National Institute of Angiology and Vascular Surgery (January / 2011- December / 2015). The variables analyzed were: age, gender, skin color, survival of the limb, state of permeability of the grafts and frequency of deaths, which as a whole will measure the effectiveness of the surgery. Results: There was a linear increase in revascularization surgeries. The mean age was 64.5 ± 9.7 years, with 67. 6 percent of people over 60 years old, and more than 60 percent were men. 52.9 percent had white skin, 80.3 percent had grade 4 according to Fontaine and 66.2 percent had severe arterial occlusion. In more than 90 percent, derivative surgery or endarterectomy was performed; 87.3 percent had affectations in the infrainguinal sector and in 64.8 percent the limb survived. There were no perioperative deaths or deaths at six months. 63 percent of the surgeries were permeable at six months. Conclusions: Arterial surgeries were effective because the majority of patients maintained the affected limb and there were no perioperative deaths neither at the six months evaluation; in addition, most of the grafts were permeable in that time(AU)

Perfusion MRI grading diffuse gliomas: Impact of permeability parameters on molecular biomarkers and survival.

BACKGROUND AND PURPOSE: Our objectives were: (1) compare dynamic susceptibility-weighted (DSC) and dynamic contrast-enhanced (DCE) permeability parameters, (2) evaluate diagnostic accuracy of DSC and DCE discriminating high- and low-grade tumors, (3) analyze relationship of permeability parameters with overall (OS) and progression-free survival (PFS) and (4) assess differences in high-grade tumors classified according to molecular biomarkers. MATERIALS AND METHODS: 49 patients with histologically proved diffuse gliomas underwent DSC and DCE imaging. Parametric maps of cerebral blood volume (CBV), CBV-leakage corrected, volume transfer coefficient (Ktrans), fractional volume of the extravascular extracellular space (EES) (Ve), fractional blood plasma volume (Vp) and rate constant between EES and blood plasma (Kep) were calculated. High-grade gliomas were also classified according to isocitrate dehydrogenase (IDH), alpha-thalassemia/mental retardation syndrome X-linked (ATRX) and O6-methylguanine-dna-methyltransferase promoter methylation (MGMT) status. RESULTS: There is correlation between parameters leakage, Ktrans and Vp. ROC curve analysis showed significance in both Ktrans and Ve for glioma grading. Threshold value of 0.075 for Ve generated the best combination of sensitivity (80%) and specificity (75%) in tumor gradation. Leakage was the only permeability parameter related to OS (P=0.006) and PFS (0.012); with prolonged survival for leakage values lower than 1.2. IDH-mutated high-grade tumors showed lower leakage and Ktrans values. High-grade tumors with loss of ATRX presented lower leakage and Vp values. CONCLUSIONS: Both DSC and DCE permeability parameters serve as non-invasive method for glioma grading. Leakage was the unique permeability parameter related to survival and the best discriminating high-grade gliomas classified according to IDH and ATRX status.

Phosphorylated ERM Mediates Lipopolysaccharide Induced Pulmonary Microvascular Endothelial Cells Permeability Through Negatively Regulating Rac1 Activity.

INTRODUCTION: The endotoxin lipopolysaccharide (LPS)-induced pulmonary endothelial barrier disruption is a key pathogenesis of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). However, the molecular mechanisms underlying LPS-impaired permeability of pulmonary microvascular endothelial cells (PMVECs) are not fully understood. METHODS: Rat PMVECs were isolated and monolayered cultured, then challenged with different doses of LPS (0.1mg/L, 1mg/L, and 10mg/L). Trans-endothelial electrical resistance (TER) was utilized to measure the integrity of the endothelial barrier. Ras-related C3 botulinum toxin substrate 1 (Rac1) activity and the phosphorylation of Ezrin/Radixin/Moesin proteins (ERM) were assessed by pulldown assay and Western Blotting. Small interfering RNA (siRNA) inhibition of Rac1 and Moesin were applied to evaluate the effect of PMVEs permeability and related pathway. RESULTS: LPS induced dose and time-dependent decreases in TER and increase in ERM threonine phosphorylation, while inactivated Rac1 activity in PMVEC. siRNA study demonstrated that both Rac1 and Moesin were involved in the mediation of the LPS-induced hyperpermeability in PMVECs monolayers, and Rac1 and Moesin could regulate each other. CONCLUSION: Phosphorylated ERM mediates LPS induced PMVECs permeability through negatively regulating Rac1 activity.

Validación de una metodología analítica por HPLC-DAD para la cuantificación de ácido benzoico complejado, en un ensayo de permeación transdérmica in vitro empleando piel de cerdo / Validation of an analytical methodology by HPLC-DAD for the quantification of complexed benzoic acid, in an in vitro transdermal permeation assay using pig skin

RESUMEN En el presente estudio se realizó la validación de una metodología analítica por cromatografía líquida de alta eficiencia con detector de arreglo de diodos (HPLC-DAD) para la cuantificación del ácido benzoico en complejos polielectrolíticos, obtenidos con Eudragit® E100. Para ello se evaluaron las características de desempeño determinando que la metodología es selectiva; lineal en el rango de concentraciones de 2 a 10 fíg/mL; precisa con un RSD inferior a un 2%; exacta con un porcentaje de recuperación de un 98,7% y se establecieron límites de cuantificación (LOQ) de 0,72 y de 1,56 (g/mL para el sistema y método respectivamente. De acuerdo a estos resultados, la metodología analítica es adecuada para evaluar la permeación in vitro, del ácido benzoico incluido en los complejos polielectrolíticos a través de piel porcina, empleando celdas de Franz.

SUMMARY This paper presents the studies carried out about the validation of an analytical methodology by high performance liquid chromatography with diode array detector (HPLC-DAD) for the quantification of benzoic acid in polyelectrolyte complexes obtained with Eudragit® E100. Performance characteristics of the methodology were evaluated, finding that this is selective; linear in the concentration range of 2 to 10 (g / mL; accurate with a RSD of less than 2%, exact with a recovery percentage of 98.7% and quantification limits of 0.72 and 1.56 fig / mL were established for the system and method respectively. According with this results, the analytical methodology is adequate to evaluate the in vitro permeation of benzoic acid, in polyelectrolyte complexes, through porcine skin in Franz cells.

Prevalencia de anticuerpos anti-Saccharomyces cerevisiae en pacientes celíacos / Prevalence of anti-Saccharomyces cerevisiae antibodies in celiac patients / Prevalência de anticorpos anti-Saccharomyces cerevisiae em pacientes celíacos

La enfermedad celíaca (EC) es una condición inflamatoria crónica del intestino delgado causada por intolerancia al gluten. El tratamiento consiste en la dieta libre de gluten (DLG). Los anticuerpos anti Saccharomyces cerevisiae (ASCA) están dirigidos contra la pared celular de la levadura, se asocian a enfermedades autoinmunes, y se propone la permeabilidad intestinal alterada como causa de activación de la inmunidad humoral. El objetivo del trabajo fue determinar la prevalencia de ASCA IgG e IgA en pacientes celíacos bajo tratamiento y evaluar la asociación de ASCA con el grado de adherencia a la DLG. Se analizaron 59 sueros de pacientes adultos celíacos con alta o baja adherencia a la DLG, y se determinó ASCA IgG e IgA. Se halló una prevalencia de ASCA IgG y/o IgA del 44%. Se encontró asociación entre ASCA-IgG y adherencia a DLG (OR 4,04 IC 95%: 1,32-12,38). La prevalencia de ASCA en la población celíaca estudiada es similar a la reportada en la bibliografía. La menor prevalencia de ASCA IgG en pacientes con una estricta DLG respecto de aquellos con baja adherencia, indicaría que su presencia depende del nivel de ingesta de gluten, sugiriéndolos como herramienta complementaria en el seguimiento del paciente celíaco.

Celiac disease (CD) is a chronic inflammatory condition of the small intestine caused by gluten intolerance. The treatment consists of gluten free diet (GFD). Anti Saccharomyces cerevisiae antibodies (ASCA) are directed against the cell wall of yeast, associated with autoimmune diseases, and an altered intestinal permeability is proposed as a cause of activation of humoral immunity. The objective of this work was to determine the prevalence of IgG and IgA ASCA in celiac patients under treatment and to evaluate the association of ASCA with the degree of adherence to GFD. Fifty-nine serum samples from adult celiac patients with high or low adherence to GFD were analyzed, determining IgG and IgA ASCA. A 44% prevalence of IgG and/or IgA ASCA was found. An association was discovered between IgG ASCA and GFD adherence (OR 4.04, 95% CI: 1.32-12.38). The prevalence of ASCA in the studied celiac population is similar to that reported in the literature. The lower prevalence of IgG ASCA in patients with a strict GFD compared to those with low adherence would indicate that their presence depends on the level of gluten intake, suggesting them as a complementary tool in the follow-up of the celiac patient.

A doença celíaca (DC) é uma condição inflamatória crônica do intestino delgado causada pela intolerância ao glúten. O tratamento consiste na dieta sem glúten (DSG). Os anticorpos anti Saccharomyces cerevisiae (ASCA) são dirigidos contra a parede celular da levedura, associados a doenças autoimunes, e à permeabilidade intestinal alterada como causa da ativação da imunidade humoral. O objetivo foi determinar a prevalência de ASCA IgG e IgA em pacientes celíacos em tratamento; avaliar a associação de ASCA com o grau de adesão ao DSG. Foram analisados 59 soros de pacientes celíacos adultos com alta ou baixa adesão ao DSG, determinando ASCA IgG e IgA. Foi encontrada uma prevalência de SCA IgG/ou IgA de 44%. Foi encontrada uma associação entre ASCA-IgG e a adesão ao DSG (OR 4,04 IC 95% 1,32-12,38). A prevalência de ASCA na população celíaca estudada é semelhante à relatada na literatura. A menor prevalência de ASCA IgG em pacientes com rigorosa DSG, em comparação àqueles com baixa adesão, indicaria que sua presença depende do nível de ingestão de glúten, sugerindo-os como uma ferramenta complementar no seguimento do paciente celíaco.

Diferentes Protocolos de Grabado Ácido en Dentina; Estudio Micromorfológico / Different protocols for acid etching in dentin; micromorphological study

RESUMEN: El objetivo fue evaluar las características de túbulos dentinarios expuestos por acción de diferentes protocolos de grabado en distintas zonas dentinarias. Se midió densidad tubular y diámetro. Se estudiaron 60 primeros premolares humanos sanos sometidos a tratamiento de endodoncia. Se realizaron cortes de las raíces a 5mm del límite amelocementario y en sentido longitudinal bucolingual, obteniendo mitades iguales (mesial y distal) que se agruparon según tratamiento acondicionador a recibir: Control, EDTA, H3PO4 15 y 45 seg., y H3PO4 15 y 45 seg. + NaOCl. Se realizó análisis en MEB en tres sectores: dentina coronaria, cámara pulpar e inicio del conducto radicular. La comparación entre las secciones se analizó mediante prueba t de Student para datos apareados, fijando valor p<0,05 para significación estadística. Se utilizó programa Infostat versión profesional 2009. No se observaron diferencias significativas en los grupos al comparar densidad tubular para las tres zonas estudiadas. Al comparar diámetro de los túbulos, se obtuvieron valores mayores cuando se acondicionó con ácido ortofosfórico al 45% + NaOCl. Los resultados ponen de manifiesto el comportamiento clínico heterogéneo de las distintas zonas dentinarias luego de diferentes protocolos para adhesión con técnica de grabado total. Protocolo tradicional de acondicionamiento con ácido ortofosfórico al 35% por 15 segundos no asegura grabado uniforme de las tres zonas dentinarias estudiadas. Protocolos donde se aumenta el tiempo de grabado y/o se incorpora NaOCl al 5% por un minuto como agente desproteinizante podrían permitir patrones más predecibles y apropiados de grabado en las tres zonas estudiadas de dientes endodonciados.

ABSTRACT: Evaluate in endodontically treated teeth the effects of different etching protocols on dentinal tubule exposure and diameter at three dentin zones. Sixty healthy first premolars from human volunteers were studied. Each tooth received endodontic treatment. Teeth were transversely sectioned 5 mm below amelocemental junction and longitudinaly sectioned in the buccolingual direction, obtaining two crown halves. Each crown half was grouped according to etching protocol into: Control, EDTA, H3PO4 15 and 45 sec., y H3PO4 15 and 45 seg. + NaOCl. Three dentinal areas were analyzed with scanning electron microscope (SEM) within each tooth: coronal dentin, pulp chamber dentin and the beginning of the root canal. Comparison between dentin zones for each treatment was made with Student's t-test for paired data, using P<0.05 for statistical significance. No significant differences in dentinal tubule exposure within the three studied zones were found. However, when comparing tubule diameter, higher values were obtained at the three dentin zones studied when H3PO4 and NaOCl wer used in combination. The results of this study showed heterogeneous behavior of different dentin zones after exposing them to various total etch protocols. The use of 37% H3PO4 for 15s did not ensure a uniform etch in the three studied zones. Protocols with H3PO4 for 45s with 5%NaOCl for 1 min, incorporated as a deproteinizing agent, could allow more predictable and appropriate etching patterns in endodontically treated teeth.

Evaluation of Microleakage by Gas Permeability and Marginal Adaptation of MTA and BiodentineTM Apical Plugs: In Vitro Study / Evaluación de la microfiltración por permeabilidad de gas y adaptación marginal de tapones apicales de MTA y BiodentineTM: Estudio in vitro

Abstract The endodontic treatment of teeth with incomplete development is always a complex task. Nowadays, biomaterials such as bioceramics offers promising clinical evidence that supports its use. However, the standardization of its use for apexification purpose still needs a deeper understanding of the materials' behavior. The aim of this investigation was to evaluate the marginal adaptability and microleakage by gas permeability of MTA and Biodentine™ apical plugs in an in vitro model. Materials and methods: Twenty- four single rooted human teeth were selected according to previously stablished inclusion criteria. All samples were prepared obtaining standard cylindrical internal canals with a diameter of 1.3 mm. Root canals were gently rinsed using 5.25% sodium hypochlorite and EDTA 17%. The apical 3mm and remaining coronal dental structure were sectioned to obtain 10mm roots. Roots were randomly assigned to 3 different groups as follows: GROUP A: MTA (n=10), GROUP B: Biodentine™ (n=10) and Group C: Control (positive n=1, negative n=3). MTA and Biodentine™ were prepared according to manufacturer's indications, and apical plugs of 4mm were passively placed in the correspondent teeth. All samples were stored in saline solution for 7 days at 37°C before evaluation. Samples were mounted in cylindrical sample-holders using epoxy resin. Microleakage was evaluated with an automatic permeability detector that calculates nitrogen diffusion between the material-root interphase. After microleakage evaluation, the samples were recovered and analyzed by scanning electron microscopy (SEM). Microleakage results were analyzed using Chi-square and adaptation was evaluated with a descriptive analysis. Results: None of the evaluated materials completely avoided the nitrogen microleakage (positive leakage of 10% and 20% of samples for MTA and Biodentine™ respectively); with no statistical significant difference between groups (p=0.527). All apical plugs showed good adaptation under SEM, at 30x, 200x, 1000x and 2500x; with microscopical structures similar to previous reports. Conclusions: Both bioceramics behave similar when used as apical barriers to avoid permeability, with acceptable marginal adaptation. Further in vivo studies are needed to validate these results.

Resumen El tratamiento endodóntico de dientes con desarrollo incompleto es siempre una tarea compleja. Hoy en día, biomateriales como las biocerámicas ofrecen una evidencia clínica prometedora que apoya su uso. Sin embargo, la estandarización de su uso para fines de apexificación todavía necesita una comprensión más profunda del comportamiento de los materiales. El objetivo de esta investigación fue evaluar la adaptabilidad marginal y microfiltración por permeabilidad de gas de los tapones apicales de MTA y Biodentine™ en un modelo in vitro. Materiales y métodos: Veiticuatro dientes humanos uniradiculares fueron seleccionados meticulosamente según criterios de inclusión previamente establecidos. Todas las muestras fueron preparadas con canales cilíndricos internos estandarizados de 1,3 mm de diámetro. Los conductos radiculares fueron gentilmente lavados con hipoclorito de sodio al 5,25% y EDTA al 17%. La estructura dental apical de 3 mm y la coronal restante se seccionó para obtener raíces de 10 mm de longitud. Las raíces se asignaron aleatoriamente a 3 grupos diferentes de la siguiente manera: GRUPO A: MTA (n = 10), GRUPO B: Biodentine™ (n = 10) y Grupo C: Control (n = 1 positivo, n = 3 negativos). El MTA y Biodentine™ se prepararon de acuerdo con las indicaciones de los fabricantes, y se colocaron pasivamente los tapones apicales de 4 mm en los dientes correspondientes. Todas las muestras se almacenaron en solución salina durante 7 días a 37ºC antes de la evaluación. Las muestras se montaron en porta-muestras cilíndricos utilizando resina epóxica. La microfiltración se evaluó con un detector de permeabilidad automática que calcula la difusión de nitrógeno entre la interfase material-raíz. Después de la evaluación de microfiltración, las muestras fueron recuperadas y analizadas por microscopía electrónica de barrido (SEM). Los resultados de microfiltración se analizaron utilizando una prueba estadística de Chi-cuadrado y la adaptación se evaluó con un análisis descriptivo. Resultados: Ninguno de los materiales evaluados evitó completamente la microfiltración de nitrógeno (fuga positiva de 10% y 20% de muestras para MTA y Biodentine™, respectivamente); sin diferencias estadísticamente significativas entre los grupos (p = 0,527). Todos los tapones apicales mostraron una buena adaptación bajo SEM, a 30x, 200x, 1000x y 2500x; con morfologías similares a las previamente reportadas. Conclusiones: ambas biocerámicas se comportan de forma similar cuando se usan como barreras apicales para evitar la permeabilidad de gas, con adaptación marginal aceptable. Se necesitan más estudios in vivo para validar estos resultados.