Polycaprolactone/Beta-Tricalcium Phosphate Scaffolds Obtained via Rotary Jet-Spinning: in vitro and in vivo Evaluation.

This study aimed to evaluate in vitro and in vivo polymeric membranes obtained by a rotary jet-spinning process for the repair of critical bone defects in the calvaria of Wistar rats, for future use in tissue engineering. Experimental sample collections were performed on the 30, 60 and 90th postoperative days, and the analyses performed were histomorphometric, immunohistochemistry, and western blotting. Reducing inflammatory infiltrate in all groups and experimental periods, angiogenesis on the 30th day did not show any difference between the groups, on the 60th day, 5% polycaprolactone/beta-tricalcium phosphate(PCL/ß-TCP) was high compared to control (C), and on the 90th day, the same group reduced when compared to C and 10% PCL/ß-TCP. The fibroplasia presented oscillations in every segment; on the 30th and 60th day, there was an increase in 5% PCL/ß-TCP, which decreased by the 90th day compared to group C. 10% PCL/ß-TCP decreased compared to C on the 60th and 90th day. The percentage of the collagen area remained high in all groups and all experimental periods. Immunohistochemistry quantifications showed variations in bone metabolism suggesting new bone formation. The 5 and 10% PCL/ß-TCP scaffold were promising for the bone regeneration process because they participated in the modulation of inflammation, angiogenesis, fibroplasia, and collagenosis.

Elastin-derived scaffolding associated or not with bone morphogenetic protein (BMP) or hydroxyapatite (HA) in the repair process of metaphyseal bone defects.

Tissue engineering represents a promising alternative for reconstructive surgical procedures especially for the repair of bone defects that do not regenerate spontaneously. The present study aimed to evaluate the effects of the elastin matrix (E24/50 and E96/37) incorporated with hydroxyapatite (HA) or morphogenetic protein (BMP) on the bone repair process in the distal metaphysis of rat femur. The groups were: control group (CG), hydrolyzed elastin matrix at 50°C/24h (E24/50), E24/50 + HA (E24/50/HA), E24/50 + BMP (E24/50/BMP), hydrolyzed elastin matrix at 37°C/96h (E96/37), E96/37 + HA (E96/37/HA), E96/37 + BMP (E96/37/BMP). Macroscopic and radiographic analyses showed longitudinal integrity of the femur in all groups without fractures or bone deformities. Microtomographically, all groups demonstrated partial closure by mineralized tissue except for the E96/37/HA group with hyperdense thin bridge formation interconnecting the edges of the ruptured cortical. Histologically, there was no complete cortical recovery in any group, but partial closure with trabecular bone. In defects filled with biomaterials, no chronic inflammatory response or foreign body type was observed. The mean volume of new bone formed was statistically significant higher in the E96/37/HA and E24/50 groups (71.28 ± 4.26 and 66.40 ± 3.69, respectively) than all the others. In the confocal analysis, it was observed that all groups presented new bone markings formed during the experimental period, being less evident in the CG group. Von Kossa staining revealed intense calcium deposits distributed in all groups. Qualitative analysis of collagen fibers under polarized light showed a predominance of red-orange birefringence in the newly regenerated bone with no difference between groups. It was concluded that the E24/50 and E96/37/HA groups promoted, with greater speed, the bone repair process in the distal metaphysis of rat femur.

Métodos avançados para tratamento de queimaduras: uma revisão / Advanced methods for the treatment of burns: a review / Métodos avanzados para el tratamiento de quemaduras: una revisión

Introdução: As lesões cutâneas por queimadura são consideradas uma das causas frequentes de mortalidade e grave incapacidade em longo prazo. Visando a reabilitação desses indivíduos, materiais biocompatíveis destinam-se a mimetizar a matriz extracelular em um microambiente para o crescimento de células in vitro. Objetivo: Apresentar metodologias desenvolvidas no tratamento de lesões de pele. Método: Trata-se de uma revisão narrativa na qual o levantamento bibliográfico deu-se por fontes de evidência primária e secundária, tais como: Biblioteca Nacional de Medicina dos Estados Unidos da América (MEDLINE) via PubMed e SciVerse Scopus. Como complementaridade na pesquisa, livros e endereço eletrônico de associações médicas-científicas e governamentais correspondentes a publicações dos últimos cinco anos foram utilizados. Resultados: Verificaram-se diferentes possibilidades para o tratamento de lesões de pele. Dentre as quais, o desenvolvimento de "Materiais Inteligentes" e sua interação com o tecido biológico numa leitura simultânea de biomarcadores capazes de replicar funções de órgãos seria auspicioso, em um sistema de cultura dinâmico e tecnologia futurista. Conclusão: Técnicas promissoras avançam no desenvolvimento de substitutos de pele funcionais em sua organização multiescalar

Introduction: Cutaneous burn injuries are considered one of the frequent causes of mortality and severe long-term disability. Aiming at the rehabilitation of these individuals, biocompatible materials are intended to mimic the extracellular matrix through a microenvironment for cell growth in vitro. Objective: To present methodologies developed in the treatment of skin lesions. Methods: This is a narrative review which was based on primary and secondary evidence sources, such as: National Library of Medicine of the United States of America (MEDLINE) through PubMed and SciVerse Scopus. As a complement to the research, books and electronic address of medical-scientific and governmental associations corresponding to publications of the last five years were used. Results: There were different possibilities for the treatment of skin lesions. Among them, the development of "Intelligent Materials" and their interaction with biological tissue in a simultaneous reading of biomarkers capable of replicating organ functions would be auspicious, in a dynamic culture system and futuristic technology. Conclusion: Promising techniques advance towards the development of functional skin substitutes in their multiscalar organization

Introducción: Las lesiones cutáneas resueltas de quemaduras son consideradas una de las causas frecuentes de mortalidad y grave incapacidad a largo plazo. Visando la rehabilitación clínica de estos individuos, los materiales biocompatibles se destinan a mimetizar la matriz extracelular a través de un microambiente para el crecimiento de células in vitro. Objetivo: Exponer metodologías desarrolladas en el tratamiento de lesiones de piel. Método: Se trata de una revisión narrativa donde el levantamiento bibliográfico se dio por fuentes de evidencia primaria y secundaria, tales como: la Biblioteca Nacional de Medicina de los Estados Unidos de América (MEDLINE) vía PubMed y SciVerse Scopus. Como complementariedad en la investigación, libros y los sitios en internet de asociaciones médicas-científicas y gubernamentales correspondientes a publicaciones de los últimos cinco años se utilizaron. Resultados: Se verificaron diferentes posibilidades para el tratamiento de lesiones de piel. Entre las cuales, el desarrollo de "Materiales Inteligentes" y su interacción con el tejido biológico en una lectura simultánea de biomarcadores capaces de replicar funciones de órganos sería auspicioso, en un sistema de cultura dinámica y tecnología futurista. Conclusión: Técnicas prometedoras avanzan en el desarrollo de sustitutos de piel funcionales en su organización multiescalar.

Avaliação do possível efeito tóxico de um alcano semifluorinado de uso oftalmológico sobre cultura de células Vero / Assessment of the possible toxic effect of a semifluorinated alkane on Vero cell culture

OBJETIVOS: Perfluorocarbonos líquidos (PFCLs) são usados em cirurgias oftalmológicas de vítreo-retina. Os PFCLs podem causar reações inflamatórias, danos celulares e destruição da arquitetura normal da retina. Na tentativa de se evitar estes efeitos, foram desenvolvidos os alcanos semifluorinados (ASF). Este trabalho avaliou o uso potencial de um ASF, o perfluorohexiloctano (F6H8), como substituto do vítreo de longo prazo em condições controladas por meio de cultura celular. MÉTODOS: Foi feita análise da citotoxicidade indireta, na qual as células entram em contato apenas com elementos solúveis que pudessem ser eliminados pelo perfluorohexiloctano. Avaliou-se então a toxicidade direta, ou seja, a toxicidade mediada pelo contato, do perfluorohexiloctano por meio de microscopia eletrônica de varredura e a imunocitoquímica para a actina. Utilizou-se como controle, células em meio de cultura livre de qualquer tratamento, um controle positivo para toxicidade, que apresenta comprovado efeito tóxico às células, e um controle de peso que exercesse compressão mecânica similar à quantidade de perfluorohexiloctano utilizada no experimento. RESULTADO: Observou-se que o referido produto não apresenta toxicidade indireta. Os ensaios de toxicidade direta mostraram que as alterações celulares promovidas pelo perfluorohexiloctano eram similares àquelas exercidas pelo controle de peso e distintas do controle de toxicidade. CONCLUSÕES: O perfluorohexiloctano não apresenta toxicidade indireta e tem efeito mais compressivo do que tóxico sobre as células em cultura.

Effects of aggrecan on schwann cell migration in vitro and nerve regeneration in vivo

Although the role of many small proteoglycans in regeneration of the nervous system has been established, little is known about the involvement of large proteoglycans. In this study, we evaluated the effects of aggrecan, a high molecular mass proteoglycan, on Schwann cells in vitro and investigated its effects on axonal regeneration after sciatic nerve tubulization. The number of regenerated axons and their morphometrical parameters were determined in vivo. Aggrecan increased the number and viability of Schwann cells in vitro. Similarly, the number of regenerated fibers increased significantly when aggrecan was applied in vivo, but there were no alterations in the morphometrical parameters. These results indicate that aggrecan contributes to the regeneration of peripheral axons and has a positive effect on the Schwann cells.