In this work, an active screen plasma discharge system based technology was incorporated in a PECVD reactor for DLC films growth, making it a new development in DLC films deposition. In this case, the active screen system is used to seek better electrons confinement, which might result in high ions density due to the collisions number increase, leading to a possible increase in ionization. DLC films were grown on steel substrates, using two variations of this system. In order to enhance adhesion between coating and substrate, a silicon interlayer was deposited, using different bias voltages. Morphological and structural characterization was performed by scanning electron microscopy, optical profilometry and Raman scattering spectroscopy. Tribological tests were performed by nanohardness, scratch and wear tests. Results showed that the plasma confinement promoted good films adhesion, which may be related to a high sub-implantation. This might be a consequence of the pressure decrease, as well as, to the ions energy distribution narrowing.

The MeOH extract of Piper ecuadorense Sodiro, Piperaceae, was chosen for metabolite isolation and elucidation due to the strong antifungal activity exhibited, measured by means of the broth microdilution method. Two known flavonoids: pinostrobin (1) and pinocembrin (2) were isolated from 4.16 g. of dichloromethane extract by column chromatography, using a gradient of hexane/EtOAc. A total of 20 mg of 1 were obtained from the fraction eluted with hexane-EtOAc 95:5 v/v, and 100 mg of 2 were obtained from the fraction eluted with hexane-EtOAc 85:15 v/v. The MIC values of the MeOH extract was 31.25 µg/mL for Trichophyton mentagrophytes ATCC® 28185 and 62.5 µg/mL for Trichophyton rubrum ATCC® 28188. The MIC value of pinocembrin was 125 µg/mL for Trichophyton mentagrophytes ATCC® 28185 and Trichophyton rubrum ATCC® 28188. Pinostrobin in antifungal test was not active against fungi tested.

The arteries that irrigate the lung face of the heart and the posterior surface of the right ventricle present a variable expression. 154 fresh hearts were evaluated obtained as autopsy material. The coronary arteries were subjected to injection process with synthetic resins. Right posterolateral branch (right dominance) was observed in 24 hearts (15.6%), of which 20 (83.3%) originated of the right coronary artery and 4 of the marginal right artery. Within these in 40% of the cases were observed in short posterior interventricular branch and 5.6% with long branch (p = 0.001). It was observed diagonal branches in 74 hearts (48%), anterosuperior branches in 126 (81.8%) and lateral branches in 123 (79.9%). The branches of middle longitude were the most frequent: diagonals (52.3%); anterosuperiors (62.7%) and laterals (47.1%). The calliper of the diagonal branches was of 2.01 mm (SD 0.59). Of the diagonal branches, those that presented smaller calliper corresponded to the specimens with left dominance (1.88 mm SD 0.52), without significance (P 0.608), while the lateral branches of more calliper corresponded to hearts with left dominance (p=0.022). It was also observed myocardial bridges in 11 diagonal branches (14.9%); in 6 anterosuperior branches (4.8%) and in 2 right posterolateral branches (8.3%). The lateral branches do not presented myocardial bridges. Prevalence of the right posterolateral branch was observed in a sixth of the individuals with right dominance, and the majority of diagonal branches presented an epicardic course that concluded in the middle third of the obtuse face of the heart.

Las arterias que irrigan la cara pulmonar del corazón y la superficie posterior del ventrículo derecho presentan una expresión variable. Se evaluaron 154 corazones frescos de material de autopsia. Las arterias coronarias fueron sometidas a proceso de inyección con resinas sintéticas. Se observó la rama posterolateral derecha (sólo en dominancia derecha) en 24 corazones (15,6 %), de los cuales 20 (83,3%) se originaron directamente de la arteria coronaria derecha y 4 de la marginal derecha. Ésta estuvo presente en el 40% de los casos que tenían una rama interventricular posterior corta y en el 5,6% con presencia de rama larga (p= 0,001). Se observó además, ramas diagonales en 74 corazones (48%), ramas anterosuperiores en 126 (81,8%) y ramas laterales en 123 (79,9%). Las ramas de longitud media fueron las más frecuentes: diagonales (52,3%); anterosuperiores (62,7%) y laterales (47,1%). El calibre de las ramas diagonales fue de 2,01 mm (DE 0,59). De las ramas diagonales, las que presentaron menor calibre correspondieron a los especímenes con dominancia izquierda 1,88 mm DS 0,52), sin ser significativo (P 0,608), mientras que las ramas laterales de mayor calibre correspondieron a corazones con dominancia izquierda (p=0,022). De las ramas diagonales se observaron puentes miocárdicos en 11 muestras (14,9%); 6 (4,8%) en las ramas anterosuperiores y 2 (8,3%) en los corazones que presentaban ramas posterolaterales derechas. Las ramas laterales no presentaron puentes miocárdicos. Se observó presencia de la rama posterolateral derecha en un sexto de los individuos con dominancia derecha y las ramas diagonales presentaron, en su mayoría, un curso epicárdico que finalizó en el tercio medio de la cara obtusa del corazón.

Major problems with valve bioprostheses are associated with progressive structural deterioration and calcification, directly associated with the use of glutaraldehyde (GA). This work describes the effects of GA processing and borate/glutamic acid buffer treatment on the mechanical, thermal and morphological properties of 0.5% GA crosslinked bovine pericardium (BP). The results showed that while the treatment of 0.5% GA crosslinked BP with borate/glutamic acid significantly improves the mechanical properties, it had no visible effect on surface morphology. Better surface preservation was only achieved for BP pre-treated with a lower GA concentration followed by the conventional treatment (0.5% GA). Improvements in mechanical properties probably arises from structural changes probably involving the depolymerization of polymeric GA crosslinks and an increase electrostatic interaction due to covalent binding of glutamic acid to free carbonyl groups (Schiff base).The results indicate that the treatment GA crosslinked BP with borate/glutamic acid buffer may be an attractive procedure for the manufacture of heart valve bioprostheses.

Criança de seis anos portadora de atresia pulmonar com comunicação interventricular, submetida a correção total com um ano, empregando monoválvula de pericárdio bovino na reconstrução da via de saída do ventrículo direito. Evoluiu com importante regurgitação valvar pulmonar (RVP) e disfunção do ventrículo direito. Na reoperação foi implantado homoenxerto pulmonar criopreservado (HPC) com anuloplastia, utilizando anel de Delrin com o intuito de evitar distorção geométrica do conduto. Após dois anos, o ecocardiograma, semelhante ao pós-operatório imediato, demonstra RVP discreta e função ventricular direita normal, sugerindo que essa manobra pode ser utilizada como coadjuvante para otimizar o resultado do implante do HPC.

A six-year-old child was suffering from pulmonary atresia with ventricular septal defect after a total correction at 1 year of age using a bovine pericardial monocusp valve in the reconstruction of the right ventricle outflow tract. The infant evolved with significant pulmonary valve regurgitation (PVR) and right ventricle dysfunction. On reoperation, a cryopreserved pulmonary homograft (CPH) was implanted with annuloplasty utilizing a Delrin ring with the aim of avoiding geometric distortion of the vessel. After two years, an echocardiogram proved a similar state to the immediate postoperative period with slight pulmonary valve regurgitation and normal right ventricular function suggesting that this maneuver may be used as coadjuvant treatment to optimize the result of CPH implantation.

OBJETIVO: Neste estudo, tivemos como objetivo comparar a resistência mecânica do pericárdio decelularizado com o pericárdio convencional, assim como avaliar sua capacidade de induzir resposta inflamatória em modelo experimental com ratos. MÉTODO: Dividimos os pericárdios em: Grupo I - pericárdio submetido a tratamento convencional com glutaraldeído e Grupo II - pericárdio submetido a tratamento de decelularização, previamente ao tratamento convencional. Após o processamento químico, as amostras do Grupo II foram histologicamente avaliadas para confirmar a eficácia da decelularização. A seguir, apenas para análise da resistência mecânica por testes de tração e de desnaturação térmica, os pericárdios foram divididos em: grupo 1 (pericárdio convencional com critérios de aprovação), grupo 2 (pericárdio convencional com critérios de reprovação) e grupo 3 (pericárdio decelularizado). A capacidade de induzir resposta inflamatória foi avaliada em estudo experimental em 50 ratos Wistar, os quais foram submetidos a implante subcutâneo de fragmentos dos pericárdios. Nossa terceira etapa de avaliação consistiu em confeccionar três biopróteses com o pericárdio decelularizado e que foram submetidas à avaliação hidrodinâmica, juntamente com uma bioprótese convencional de teste. RESULTADOS: A análise histológica inicial demonstrou decelularização completa. A resistência mecânica mostrou diferença significativa com relação às variáveis "tensão de ruptura" e "índice de tenacidade". Não encontramos diferença quanto à atividade inflamatória em modelo experimental com ratos. O desempenho hidrodinâmico foi semelhante e todas biopróteses atingiram a marca de 150 milhões de ciclos. A avaliação histológica ao fim da ciclagem mostrou padrão microscópico habitual, não havendo ruptura ou fragmentação anormal induzida por estresse mecânico. CONCLUSÃO: A decelularização mantém a resistência física do pericárdio, além de não induzir resposta inflamatória diferente daquela habitualmente encontrada no pericárdio convencional.

INTRODUCTION: In this paper, our objective was to compare the decellularized and conventional pericardium mechanical resistance and also its capability of inducing inflammatory response in an animal experimental model. METHOD: In order to study these properties, we divided the pericardia into two groups: Group I - pericardium conventionally treated with GTA - and Group II - pericardium previously decellularized and then treated with GTA in the conventional way. After the chemical treatment, Group II samples were histologically evaluated to confirm the efficacy of the decellularization process. Then, only for the analysis of mechanical resistance, pericardia were divided in: Groups 1 (conventional pericardia with criteria of approval), 2 (conventional pericardial with criteria of disapproval) and 3 (decellularized pericardia). The capacity of inducing inflammatory response was tested in a rat experimental model with 50 Wistar rats, in which rats of each group received patches of the pericardia in the abdomen. Our third step of analysis was manufacturing three decellularized pericardium bioprosthesis which were submitted to hydrodynamic evaluation together with a conventional bioprosthesis test. RESULTS: The histological analysis showed complete decellularization. Mechanical resistance gave statistical differences in the "tension of rupture" and "tenacity index" tests. We found no difference in the inflammatory activity in the animal model. Hydrodynamic performance was similar and all prostheses reached 150 million cycles. The final histological analysis assessed the standard microscopic pattern, and no rupture or abnormal fragmentation caused by mechanical stress. CONCLUSION: The decellularization technique maintains the physical resistance of the pericardium when compared with the conventionally prepared pericardium. And also, there was no difference in both groups regarding to inflammatory response studied in the animal model.

OBJETIVO: Estudar bioprótese com descontinuidade do anel de sustentação, a bioprótese "Less Stented ®". O objetivo da fase 1 do trabalho foi o seu estudo "in vitro", onde foram avaliadas as características hemodinâmicas. O objetivo da fase 2 é relatar a experiência clínica inicial. MÉTODO: As biopróteses foram confeccionadas e avaliadas laboratorialmente na Braile Biomédica, em São José do Rio Preto, São Paulo. São próteses de pericárdio bovino, tratadas com glutaraldeído, segundo os mesmos padrões das próteses "stented". As próteses foram testadas no simulador de pulso e analisadas em simulador cardíaco. Foi realizada análise clínica e laboratorial (ecoDopplercardiografia e ressonância magnética) dos pacientes. RESULTADOS: A análise do gradiente pressórico transvalvar mostrou que ao longo do fluxo médio, equivalente ao débito cardíaco e que variou de 4,39 a 7,96 l/min, o gradiente transvalvar se manteve dentro de níveis clinicamente aceitáveis (6,37 a 11,62 mmHg). A curva de regressão mostrou boa correlação com o aumento de débito cardíaco com R² = 0,8291. A fração regurgitante variou de 10,95 a 17,94%, sendo que a fração de vazamento variou de 4,49 a 7,87%. Quanto ao coeficiente de descarga, ao índice de performance e ao de eficiência, verificou-se que esses parâmetros mostraram comportamento favorável com aumento progressivo do débito cardíaco, com excelente correlação tanto para o coeficiente de descarga, quanto para o índice de performance e o índice de eficiência (R² respectivamente, 0,9385; 0,9332; 0,9024). Os dois pacientes submetidos ao implante da bioprótese "Less- Stented®" apresentaram evolução clínica satisfatória. CONCLUSÃO: A bioprótese "Less-Stented®"poderá representar uma nova alternativa de substituto valvar.

OBJECTIVE: To study a bioprosthesis with discontinuation of the annular support, named the "Less Stented®" bioprosthesis. The Phase 1 objective was the "in vitro" study, during which the hemodynamic characteristics were analyzed. Phase 2 of this study consisted of an initial clinical implant protocol. METHOD: The "Less Stented" bioprosthesis consists in a glutaraldehyde treated bovine pericardium prosthesis manufactured by Braile Biomedica Ltda, São José do Rio Preto, São Paulo, Brazil, using the same manufacturing protocols as the stented bioprosthesis but with discontinuation of the annular suport. Bioprostheses were tested in a pulse simulator system and analyzed in cardiac simulator. with respect to the transvalvular gradient, regurgitant fraction and leakage volume, discharge coefficient, performance and efficiency index. The two patients of clinical protocol were analyzed according to the functional class (NYHA), an echocardiographic study and magnetic resonance, in both pre and postoperative periods. RESULTS: The transvalvular gradients ranged between 6.37 and 11.62 mmHg with a mean flow between 4.39 and 7.96 L/min, giving a good correlation (0.8291) on the regression curve with the increase in flow. The regurgitant fraction ranged between 10.95% and 17.94% and leakage volume between 4.49% and 7.87%. The discharge coefficient, performance and efficiency index showed favorable behavior with the flow increase, with good coefficient correlations for all three variables (0.9385, 0.9332 and 0.9024, respectively). The two patients submitted to "Less Stented®" bioprostheses implant presented good clinical evolutions. CONCLUSION: "Less Stented®" bioprostheses may represent a new alternative to aortic valve replacement.

Este trabalho descreve um novo processo para a reticulação de matrizes de colágeno com glutaraldeído para a preparação de materiais para a confecção de válvulas cardíacas biológicas, e consiste no tratamento do pericárdio bovino com concentrações progressivamente crescentes com este reagente no intervalo de concentração entre 0,005 e 0,5% em tampão fosfato, pH 7,4. O perfil da reação com glutaraldeído, quando comparado com o procedimento convencional, foi mais homogêneo e os materiais obtidos apresentaram propriedades térmicas e mecânicas similares. Entretanto, mostraram-se significativamente mais estáveis à degradação enzimática, principalmente em relação à tripsina (17 x), que é devido provavelmente à formação de ligações de reticulação mais homogêneas e/ou em maior densidade. Os resultados mostram que metodologia seqüencial estudada, associada ao tratamento convencional, pode constituir-se em uma técnica de pré-tratamento promissora para a preparação de materiais mais eficientes para confecção de biopróteses.

This work describes a new process for crosslinking of collagen matrices with glutaraldehyde for the preparation of improved material for biological heart valve manufacture which consists in the treatment of bovine pericardium with low and progressive increasing concentrations of glutaraldehyde from 0.005 to 0.5% in phosphate buffer, pH 7.4. The crosslinking reaction profile was more homogeneous compared to the conventional procedure and the material was characterized by a higher stability towards enzyme degradation, particularly in respect to trypsin hydrolysis by a factor of 17 times, with the required thermal and elastic properties. This increased enzyme stability is probably due to a more homogeneous crosslink distribution and/or increased density within the collagen matrix. The results showed that the sequential procedure may be a potential and efficient pre-treatment technique for the preparation of bovine pericardium derived materials for the manufacture of bioprosthesis.