Potencial das membranas de células-tronco mesenquimais na regeneração periodontal: uma revisão sistemática de estudos pré-clínicos em modelo animal / Potential of mesenchymal stem cell sheets on periodontal regeneration: a systematic review of pre-clinical animal studies

A periodontite é uma doença inflamatória crônica multifactorial caracterizada pela destruição progressiva do aparelho de suporte periodontal. Atualmente, as técnicas convencionais para regeneração desses tecidos periodontais perdidos tiveram sucesso limitado. A tecnologia de membranas de células usando células-tronco mesenquimais apareceu como uma estratégia promissora na medicina regenerativa periodontal. Embora estudos recentes tenham mostrado o papel das membranas de células-tronco mesenquimais (MSCSs) no aumento dos tecidos de suporte dentário e ósseo, não há uma revisão sistemática focada especificamente na avaliação da regeneração periodontal em modelos animais ortotópicos. Esta revisão tem como objetivo avaliar o potencial das MSCSs na regeneração periodontal em comparação ao controle, em modelos animais experimentais. Estudos pré-clínicos em defeitos periodontais de modelos animais foram considerados elegíveis. A busca eletrônica incluiu as bases de dados MEDLINE, Web of Science, EMBASE e LILACS. Além disso, uma busca manual avaliou as revistas científicas na área de periodontia/regeneração. A revisão sistemática foi conduzida de acordo com as diretrizes de Preferred Reporting Item for Systematic Reviews and Meta-Analyses statement guidelines. A ferramenta do Centro de Revisão Sistemática para Experimentação com Animais de Laboratório (SYRCLE) foi usada para avaliar o risco de viés. Dos 3989 estudos obtidos a partir da busca no banco de dados eletrônicos foram incluídos 17 artigos. Foram empregados MSCSs autólogos, alógenos e xenógenos para melhorar a regeneração periodontal. Estes incluíram MSCSs do folículo dentário (DF), MSCSs do ligamento periodontal (PDL), MSCSs da polpa dentária (DP), MSCSs da medula óssea (BM), MSCSs periosteais alveolares (AP) e MSCSs gengivais (G). Em relação ao protocolo de indução de células, a maioria dos estudos utilizou ácido ascórbico (52,94%), outros utilizaram placas de cultura com polímero termo responsivo (47,06%). Os efeitos adversos, em relação à utilização das MSCSs no sítio doador, não foram identificados na maioria dos estudos, mesmo com o uso adjunto de scaffolds, membranas ou ambos. Meta-análise não foi considerada devido a heterogeneidades metodológicas. PDL-MSCSs demonstrou ser superior para aumento da regeneração periodontal em comparação ao controle, mas em um microambiente inflamatório induzido, DF-MSCSs foram melhores. Os DF-MSCSs parecem estar relacionados à espessura do cemento e dimensão periodontal. Além disso, DP-MSCSs e BM-MSCSs mostraram resultados melhores em comparação com o controle. Em contraste, AP-MSCSs não foram associados a melhorias na regeneração periodontal. A avaliação do risco de viés com a ferramenta da SYRCLE revelou que 44,12% dos estudos apresentavam baixo risco de viés, 55,29% foram incertos e 0,59%, alto risco. A presente revisão sistemática mostrou que as MSCSs podem aumentar a regeneração periodontal em modelos animais de defeito periodontal, fornecendo uma estratégia promissora para aumentar a regeneração periodontal.

La matriz extracelular en la curación de las heridas cutáneas. Aspectos físicos, químicos y biológicos / Extracellular matrix in healing of cutaneous wounds. Physical, chemical and biological aspects

Se revisan los nuevos conocimientos sobre la matriz extracelular (MEC), que han permitido descubrir su importante rol en la cicatrización de las heridas cutáneas. Se describen sus características morfofisiológicas y cómo interviene en la curación de las heridas cutáneas. Se presentan cuatro casos clínicos en los que se aplicó este enfoque terapéutico: los sustitutos de piel y la "cura húmeda"

We review the new knowledge about the extracellular ma-trix (ECM) that has allowed us to discover its important role in the healing of cutaneous wounds. The morpho-physiological characteristics of ECM and its role in the healing of cutaneous wounds are described. Four clinical cases are presented where this therapeutic approach was applied: the skin substitutes and the "moist wound healing".

Application of hydrogel-loaded stem cell exosomes in the field of tissue regeneration / 生物工程学报

In recent years, mesenchymal stem cell (MSCs)-derived exosomes have attracted much attention in the field of tissue regeneration. Mesenchymal stem cell-derived exosomes are signaling molecules for communication among cells. They are characterized by natural targeting and low immunogenicity, and are mostly absorbed by cells through the paracrine pathway of mesenchymal stem cells. Moreover, they participate in the regulation and promotion of cell or tissue regeneration. As a scaffold material in regenerative medicine, hydrogel has good biocompatibility and degradability. Combining the two compounds can not only improve the retention time of exosomes at the lesion site, but also improve the dose of exosomes reaching the lesion site by in situ injection, and the therapeutic effect in the lesion area is significant and continuous. This paper summarizes the research results of the interaction of exocrine and hydrogel composite materials to promote tissue repair and regeneration, in order to facilitate research in the field of tissue regeneration in the future.

Cell-loaded hydrogel microspheres based on droplet microfluidics: a review / 生物工程学报

Droplet microfluidics technology offers refined control over the flows of multiple fluids in micro/nano-scale, enabling fabrication of micro/nano-droplets with precisely adjustable structures and compositions in a high-throughput manner. With the combination of proper hydrogel materials and preparation methods, single or multiple cells can be efficiently encapsulated into hydrogels to produce cell-loaded hydrogel microspheres. The cell-loaded hydrogel microspheres can provide a three-dimensional, relatively independent and controllable microenvironment for cell proliferation and differentiation, which is of great value for three-dimensional cell culture, tissue engineering and regenerative medicine, stem cell research, single cell study and many other biological science fields. In this review, the preparation methods of cell-loaded hydrogel microspheres based on droplet microfluidics and its applications in biomedical field are summarized and future prospects are proposed.

Resultados estéticos en defectos nasales posquirúrgicos regenerados con fibrina autóloga rica en plaquetas y leucocitos / Aesthetic results in post-surgical nasal defects regenerated with autologous platelet- and leukocyte-rich fibrin

Introducción: En la reconstrucción de los defectos cutáneos nasales se han utilizado varias técnicas a nivel mundial. Novedosas prácticas utilizan los concentrados plaquetarios por sus propiedades moduladoras y favorecedoras de la regeneración tisular. Objetivo: Determinar los resultados estéticos asociados al uso de la membrana de fibrina autóloga rica en plaquetas y leucocitos, para la regeneración de defectos cutáneos nasales posquirúrgicos. Métodos: Se realizó un estudio cuasiexperimental, longitudinal y prospectivo en el Servicio de Cirugía Maxilofacial del Hospital Universitario "Arnaldo Milián Castro" de la ciudad de Santa Clara, Villa Clara, Cuba, desde septiembre de 2015 hasta junio de 2019. Se efectuó un muestreo intencional, no probabilístico, de 31 pacientes. A partir de una donación de sangre del paciente, se obtuvo una membrana de fibrina rica en plaquetas y leucocitos, la que fue suturada en el defecto nasal posquirúrgico. Se estudiaron variables como el resultado estético, evaluado sobre la base de parámetros como la elasticidad, el color, el volumen y la superficie. Resultados: La edad media fue 62,71 ± 11,09 años y el 61,29 por ciento de la muestra correspondió al sexo masculino. Mostraron un buen resultado estético el 90,32 por ciento de los pacientes, lo que se asoció de forma significativa al grado de epitelización. Conclusiones: Se obtuvo un buen resultado estético en los pacientes donde se utilizó la membrana de fibrina autóloga rica en plaquetas y leucocitos, con independencia de la presencia de diabetes mellitus y hábitos tóxicos. El resultado estético estuvo asociado significativamente al grado de epitelización y a la edad(AU)

Introduction: In the reconstruction of nasal skin defects, several techniques have been used worldwide. Innovative practices use platelet concentrates for their modulating properties and favoring tissue regeneration. Objective: Determine the aesthetic results associated with the use of autologous fibrin rich in platelets and leukocytes, for the regeneration of post-surgical nasal skin defects. Methods: A quasi-experimental, longitudinal and prospective study was conducted in the Maxillofacial Surgery Service of "Arnaldo Milián Castro" University Hospital in the city of Santa Clara, Villa Clara province, Cuba, from September 2015 to June 2019. An intentional, non-probabilistic sampling of 31 patients was carried out. From a blood donation from the patient, a fibrin membrane rich in platelets and leukocytes was obtained, which was sutured in the post-surgical nasal defect. Variables such as the aesthetic result were studied, evaluated on the basis of parameters such as elasticity, color, volume and surface. Results: The mean age was 62.71 ± 11.09 years and 61.29 percent of the sample corresponded to the male sex. A good aesthetic result was shown by 90.32 percent of the patients, which was significantly associated with the degree of epithelialization. Conclusions: A good aesthetic result was obtained in patients where the fibrin membrane rich in leukocytes and autologous platelets was used, regardless of the presence of diabetes mellitus and toxic habits. The aesthetic result was significantly associated with the degree of epithelialization and age(AU)

Automated Assessment of Cell Infiltration and Removal in Decellularized Scaffolds - Experimental Study in Rabbits / Avaliação automatizada da infiltração e remoção celular em scaffolds descelularizados - Estudo experimental em coelhos

Abstract Objective Semiquantitative and automated measurement of nuclear material removal and cell infiltration in decellularized tendon scaffolds (DTSs). Method 16 pure New Zealand rabbits were used, and the gastrocnemius muscle tendon was collected bilaterally from half of these animals (16 tendons collected); 4 were kept as control and 12 were submitted to the decellularization protocol (DTS). Eight of the DTSs were used as an in vivo implant in the experimental rotator cuff tear (RCT) model, and the rest, as well as the controls, were used in the semiquantitative and automated evaluation of nuclear material removal. The eight additional rabbits were used to make the experimental model of RCT and subsequent evaluation of cellular infiltration after 2 or 8 weeks, within the DTS. Results The semiquantitative and automated analysis used demonstrated a removal of 79% of nuclear material (p< 0.001 and power > 99%) and a decrease of 88% (p < 0.001 and power >99%) in the area occupied by nuclear material after the decellularization protocol. On cell infiltration in DTS, an increase of 256% (p < 0.001 and power >99%) in the number of cells within the DTS was observed in the comparison between 2 and 8 weeks postoperatively. Conclusion The proposed semiquantitative and automated measurement method was able to objectively measure the removal of nuclear material and cell infiltration in DTS.

Resumo Objetivo Mensuração semiquantitativa e automatizada da remoção de material nuclear e da infiltração celular em scaffolds tendinosos descelularizados (STDs). Método Foram utilizados 16 coelhos Nova Zelândia puros, sendo o tendão do músculo gastrocnêmio coletado bilateralmente de metade destes animais (16 tendões coletados); 4 foram mantidos como controle e 12 foram submetidos ao protocolo de descelularização (STD). Dos STDs, 8 foram utilizados como implante in vivo no modelo experimental de lesão do manguito rotador (LMR) e os restantes, assim como os controles, foram utilizados na avaliação semiquantitativa e automatizada da remoção de material nuclear. Os oito coelhos adicionais foram utilizados na confecção do modelo experimental de LMR e posterior avaliação da infiltração celular após 2 ou 8 semanas, dentro do STD. Resultados A análise semiquantitativa e automatizada utilizada demonstrou uma remoção de 79% do material nuclear (p< 0,001 e poder > 99%) e uma diminuição de 88% (p< 0,001 e poder > 99%) na área ocupada por material nuclear após o protocolo de descelularização. Sobre a infiltração celular no STD, foi observado um aumento de 256% (p< 0,001 e poder > 99%) no número de células dentro do STD na comparação entre 2 e 8 semanas de pós-operatório. Conclusão O método de mensuração semiquantitativo e automatizado proposto foi capaz de mensurar objetivamente a remoção de material nuclear e a infiltração celular no STD.

Treatment of Muscle Injury with Stem Cells - Experimental Study in Rabbits / Tratamento da lesão muscular com células-tronco - Estudo experimental em coelhos

Abstract Objective Histological and macroscopic evaluation of the healing process of acute lesions of the femoral rectus muscle using stem cells derived from adipose tissue-derived stem cells (ADSCs). Method An experimental study was conducted with 18 hind legs of New Zealand rabbits, which were divided into three study groups according to the intervention to be performed. In group I, no surgical procedure was performed; in group II—SHAN, the experimental lesion was performed without any additional intervention protocol; in group III—Intervention, the addition of ADSCs was performed in the same topography of the experimental lesion. After the proposed period, 2 weeks, the material was collected and submitted to macroscopic and histological evaluation. Results The quantitative analysis showed that the addition of ADSCs is related to the reduction of inflammatory cells in the 2-week evaluation (164.2 cells in group II - SHAN to 89.62 cells in group III - ADSC). The qualitative analysis of the slides with Picrosirius red, noticed an increase in orange/yellow fibers in group III - ADSC, which evidences a final healing process. The macroscopic evaluation found no difference between the groups. Conclusion The use of ADSCs in the treatment of acute muscle injury presented histological advantages when compared to their non-use.

Resumo Objetivo Avaliação histológica e macroscópica do processo de cicatrização das lesões agudas do músculo reto femoral, com utilização de células-tronco derivadas de tecido adiposo (ADSCs, na sigla em inglês). Método Foi realizado um estudo experimental com 18 patas traseiras de coelhos Nova Zelândia, que foram divididos em três nos grupos de estudo de acordo com a intervenção a ser realizada. No grupo I não foi realizado procedimento cirúrgico; no grupo II - SHAN foi realizado a lesão experimental sem nenhum protocolo de intervenção adicional; e no grupo III - Intervenção foi realizado a adição de ADSCs na mesma topografia onde foi realizada a lesão experimental. Após o período proposto, 2 semanas, o material foi coletado, submetido a avaliação macroscópica e histológica. Resultados A análise quantitativa demonstrou que a adição de ADSCs está relacionada com a diminuição de células inflamatórias na avaliação com 2 semanas (164,2 células no grupo II - SHAN para 89,62 células no grupo III - ADSC). A análise qualitativa das lâminas coradas com Picrosírius red demonstrou um aumento das fibras de cor laranja/amarela no grupo III - ADSC, o que evidencia um processo final de cicatrização. A avaliação macroscópica não encontrou diferença entre os grupos. Conclusão A utilização de ADSCs no tratamento de lesão muscular aguda apresentou vantagens histológicas quando comparada a sua não utilização.

A importância do uso de pericárdio bovino para reconstruções cirúrgicas: uma revisão sistemática / The importance of the use of bovine pericardium for surgical reconstructions: a systematic review

Introdução: O uso de pericárdio bovino teve início em 1972 nas cirurgias cardiovasculares. A partir da evolução da engenharia de tecidos com os cuidados na preparação do material, minimizando os riscos de rejeição e facilitando a utilização para diversos tipos de cirurgias, o pericárdio bovino tornou-se ferramenta importante em procedimentos cirúrgicos reconstrutivos. Objetivos: Nessa casuística, o presente estudo propõe avaliar o atual cenário da utilização do pericárdio bovino em procedimentos cirúrgicos de diversas especialidades e os resultados pósoperatórios encontrados. Métodos: Assim, foi realizada uma revisão sistemática da literatura e a base de dados consultada foi a MEDLINE, utilizando a palavra-chave "bovine pericardium", elencando estudos publicados nos últimos cinco anos em inglês e português, e que não utilizavam outro tipo de "patch". Resultados: Foram selecionados 14 artigos que totalizam 507 pacientes, submetidos a cirurgias em diversas áreas, tais quais, cardiologia, neurologia, vascular, pediatria, urologia e oftalmologia. Conclusão: Depreende-se que o uso de pericárdio bovino como remendo cirúrgico é seguro, tendo em vista que existem poucos casos de rejeição do hospedeiro, além de fácil e rápido de ser manuseado, possuindo benefícios frente a próteses mecânicas. Faz-se relevante, portanto, ampliar o número de estudos sobre o tema, visando o grande potencial que esse tipo de material possui para a medicina regenerativa.

Introduction: The use of bovine pericardium started in 1972 in cardiovascular surgeries. From the evolution of tissue engineering with care in the preparation of the material, minimizing the risk of rejection and facilitating the use for various types of surgeries, the bovine pericardium has become an important tool in reconstructive surgical procedures. Purpose: In this series, the present study proposes to evaluate the current scenario of the use of bovine pericardium in surgical procedures of different specialties, and the postoperative results found. Methods: Thus, a systematic literature review was carried out and the database consulted was MEDLINE, using the keywords "bovine pericardium", listing studies published in the last five years in English and Portuguese and that did not use another type of patch. Results: 14 articles were selected, totaling 507 patients, who underwent surgery in several areas, such as cardiology, neurology, vascular, pediatrics, urology, and ophthalmology. Conclusion: It appears that the use of bovine pericardium as a surgical patch is safe, given that there are few cases of host rejection, in addition to being easy and quick to handle, with benefits compared to mechanical prostheses. It is relevant, therefore, to expand the number of studies on the subject, aiming at the great potential that this type of material has for regenerative medicine.

Microorganism-derived biological macromolecules for tissue engineering / 医学前沿

According to literature, certain microorganism productions mediate biological effects. However, their beneficial characteristics remain unclear. Nowadays, scientists concentrate on obtaining natural materials from live creatures as new sources to produce innovative smart biomaterials for increasing tissue reconstruction in tissue engineering and regenerative medicine. The present review aims to introduce microorganism-derived biological macromolecules, such as pullulan, alginate, dextran, curdlan, and hyaluronic acid, and their available sources for tissue engineering. Growing evidence indicates that these materials can be used as biological material in scaffolds to enhance regeneration in damaged tissues and contribute to cosmetic and dermatological applications. These natural-based materials are attractive in pharmaceutical, regenerative medicine, and biomedical applications. This study provides a detailed overview of natural-based biomaterials, their chemical and physical properties, and new directions for future research and therapeutic applications.

Tratamiento de heridas complejas mediante fibrina rica en plaquetas y leucocitos (L-PRF), experiencia inicial de un centro / Treatment of complex wounds using platelet rich fibrin and leukocytes (L-PRF), initial experience of a center

Resumen Introducción El uso de concentrados plaquetarios para el tratamiento de heridas complejas y regeneración tisular está siendo ampliamente utilizado a nivel mundial. Durante el último tiempo, la segunda generación de concentrados plaquetarios, particularmente el L-PRF, ha permitido tratar de manera efectiva a pacientes con esta patología. Debido a su bajo costo y versatilidad, ha sido posible aplicar esta técnica en variadas situaciones clínicas con buenos resultados. El objetivo de este trabajo es presentar nuestra experiencia utilizando L-PRF para la curación de heridas complejas (CHC) como una alternativa al uso de injertos de distinto grado de complejidad. Materiales y Método: Se realizó un análisis prospectivo de una serie de casos de pacientes que fueron sometidos a tratamiento quirúrgico de heridas complejas mediante el uso de L-PRF en el Hospital Santiago Oriente - Luis Tisné Brousse, entre los meses de enero de 2017 y diciembre de 2018. Mediante examen clínico y parámetros de inclusión, de éxito y de fracaso definidos previamente, se evaluó un total de 11 pacientes con heridas complejas a los cuales se les realizó un tratamiento local con injerto de L-PRF. Resultados: _La etiología de las heridas fue variada. 8 (72%) de los casos lograron una epitelización del 100% y 3 (28%) fracasaron. Se identificaron factores predisponentes para el fracaso de la técnica, y también fue posible establecer una relación de predicción de éxito en donde se relaciona una probabilidad alta de epitelización cuando la granulación de la herida ocurre durante los primeros 10 días sobre el injerto de L-PRF. Conclusión: El tratamiento de heridas complejas mediante L-PRF es una alternativa factible, de bajo costo y requerimientos (comparada con el uso de injertos, colgajos y sustitutos dérmicos), es segura en la resolución de heridas complejas, permitiendo disminuir la morbilidad, los costos asociados al tratamiento y estadía hospitalaria.

Introduction: The use of platelet concentrates for the treatment of complex wounds and tissue regenera-tion is being widely used worldwide. During the last time, the second generation of platelet concentrates, particularly L-PRF, has made it possible to effectively treat patients with this pathology. Due to its low cost and versatility, it has been possible to apply this technique in various clinical situations with good results. The objective of this work is to present our experience using L-PRF for the healing of complex wounds (HCC) as an alternative to the use of grafts of different degrees of complexity. Materials and Method: A prospective analysis was carried out with a series of cases who underwent surgical treatment of complex wounds using L-PRF at Santiago Oriente - Luis Tisné Brousse Hospital, between the months of January 2017 and December 2018. Through clinical examination and previously defined inclusion, success, and failure parameters, a total of 11 patients with complex wounds were evaluated who underwent local treatment with an L-PRF graft. Results: The etiology of the wounds was varied. 8 (72%) of the cases achieved 100% epithelialization and 3 (28%) failed. Predisposing factors for the failure of the technique were identified, and it was also possible to establish a predictive relationship of success where a high probability of epithelialization is related when the granulation of the wound occurs during the first 10 days on the L-PRF graft. Conclusion: The treatment of complex wounds using L-PRF is a feasible alternative, with low cost and requirements (compared to the use of grafts, flaps and dermal substitutes) and safe in the resolution of complex wounds, allowing to reduce morbidity, the costs associated with treatment and hospital stay.

Corrección de arrugas perioculares con plasma rico en plaquetas / Correction of periocular wrinkles with platelet-rich plasma

Las arrugas son surcos o pliegues en la piel, que aparecen principalmente por efecto del envejecimiento. Este artículo describe el caso de un paciente masculino de 47 años de edad, piel blanca, que acudió a consulta de cirugía plástica ocular por inconformidad con el aspecto envejecido de su rostro a causa de las arrugas perioculares. Se le aplicó plasma rico en plaquetas intradérmico en el trayecto de las arrugas a razón de 3 dosis con intervalo promedio de 30 días entre cada una. Se logró la corrección total de las arrugas, con buenos resultados estéticos. No se encontró reacción adversa. Se reafirma el criterio planteado por estudios de que el plasma rico en plaquetas es una opción terapéutica de primera línea para rejuvenecer la región periocular(AU)

Wrinkles are a creases or folds which appear in the skin mainly as a result of aging. A case is described of a male 47-year-old patient of white skin color who attended ocular plastic surgery consultation for dissatisfaction with the periocular wrinkles on his face, which gave it an aged appearance. Intradermal platelet-rich plasma was applied along the course of the wrinkles at three doses with an average separation of 30 days between them. Total wrinkle correction was achieved, with good esthetic results. There was not any adverse reaction. The case confirms the criterion contained in previous studies that platelet-rich plasma is a first-line therapeutic option to rejuvenate the periocular region(AU)

Ética en el ámbito de la investigación en medicina regenerativa / Ethics in the field of regenerative medicine research

Introducción: La medicina regenerativa se basa en la sustitución o regeneración de células humanas, tejidos u órganos con la finalidad de restablecer una función normal. Es una terapia basada en el tratamiento con células madre. Las estrategias terapéuticas basadas en la terapia celular permiten su empleo en diferentes enfermedades que no resuelven o tardan más en resolver por tratamientos médicos convencionales. Objetivos: Analizar aspectos éticos de la investigación que contribuyen a la reflexión cognitiva y ética de la ciencia en el ámbito de la medicina regenerativa. Métodos: Se realizó una revisión que consideró artículos originales y de corte experimental publicados en la última década, en algunas bases de datos de la Biblioteca Virtual de Salud (BVS) de Cuba. Se emplearon los descriptores del Medical Subject Headings y de Ciencias de la Salud. Análisis y síntesis de la información: Se abordan las aplicaciones y generalidades relacionadas con las células madre y los avances en la medicina regenerativa, así como los procedimientos y tratamientos con células madre para diferentes enfermedades con la aplicación de los conocimientos destinados al beneficio social del ser humano. Conclusiones: Se señala la importancia de una postura ética en la medicina regenerativa para la valoración adecuada de los avances en el tratamiento de diversas enfermedades, el impacto de la adquisición de nuevos conocimientos, así como una actitud más responsable y el desarrollo de valores sociales que forman parte de la humanidad(AU)

Introduction: regenerative medicine is based on the replacement or regeneration of human cells, tissues or organs in order to restore normal function; it is a therapy based on stem cell treatment. Therapeutic strategies based on cell therapy allow their use in different diseases that do not resolve or take longer to resolve by conventional medical treatments. Objectives: to address ethical aspects of research those contribute to cognitive and ethical reflection of science in the field of regenerative medicine research. Methods: A review was carried out that considered original and experimental articles published in the last decade, in some databases of the Virtual Health Library (VHL) of Cuba. The descriptors of the Medical Subject Headings and Descriptors in Health Sciences were used. Analysis and synthesis of the information: Applications and generalities related to stem cells and advances in regenerative medicine are summarized, as well as procedures and treatments with stem cells for different diseases with the application of knowledge aimed at the social benefit of the human being. Conclusions: the importance of an ethical posture in regenerative medicine was pointed out for the adequate assessment of the advances in the treatment of various diseases, the impact of the acquisition of new knowledge, as well as a more responsible attitude and the development of social values that they are part of humanity(AU)

Coautorias nas publicações brasileiras sobre medicina regenerativa: assimetrias na colaboração científica internacional / Brazilian co-authorships in regenerative medicine publications: inequalities in emerging countries scientific collaboration / Coautorías en las publicaciones brasileñas acerca de la medicina regenerativa: asimetrías en la colaboración científica internacional

A cooperação científica internacional tornou-se um fator essencial para que os países emergentes alcancem novos patamares de pesquisa, publicações e financiamento. No contexto de uma discussão analítica sobre a cooperação científica global, foram analisadas as publicações brasileiras indexadas na Web of Science e a coautoria entre pesquisadores locais e estrangeiros, com o objetivo de ilustrar as mudanças ocorridas na medicina regenerativa nas duas últimas décadas. O artigo conclui que, na última década, expandiu-se a coautoria entre autores brasileiros e destes com autores de países desenvolvidos, especialmente com aqueles dos Estados Unidos, mas também, em menor grau, com os de outros países emergentes e da América Latina. Pesquisadores brasileiros também publicaram artigos de impacto global, indicando a qualidade atingida, no país, pela pesquisa científica na área. A análise mostra que a colaboração abriu portas, no âmbito global, para a pesquisa local, mas também que as assimetrias científicas se mantiveram ao longo do tempo.

International scientific cooperation has become a key factor for emerging countries to improve research advancement, publication and funding. An analysis of local publications indexed in the Web of Science and co-authored between Brazilian researchers and non-residents was carried out, in the context of an analytical discussion on global scientific cooperation and with the aim of illustrating changes in the last two decades in regenerative medicine regarding this topic. The article concluded that in the last decade Brazil increased scientific co-authorships significantly domestically and with advanced country authors, especially with American authors, but also to a lesser degree with those of other emerging economies in and beyond Latin American. Local researchers have also published on their own several articles of global impact, revealing the academic quality attained in local sciences related to the area. Collaboration has undoubtedly opened doors for Brazilian regenerative medicine globally, but historical scientific inequalities remain.

La cooperación científica internacional se ha transformado en un factor sustancial para que los países emergentes progresen en investigación, publicación y financiación. Se desarrolló un análisis de publicaciones locales indexadas en la Web of Science y coautorías entre investigadores brasileños y extranjeros en el contexto de una reflexión sobre cooperación científica global y con el fin de ilustrar las modificaciones producidas en la medicina molecular regenerativa durante los dos últimos decenios. El artículo concluye que, en el último decenio, Brasil aumentó significativamente las coautorías domésticas y con autores de países avanzados, especialmente de los Estados Unidos, y en menor medida con aquellos de otras economías emergentes dentro y fuera de América Latina. Los investigadores locales han publicado varios artículos propios de impacto global, lo cual revela la calidad académica lograda, en Brasil, en el área. La colaboración ha abierto puertas en el mundo para la medicina regenerativa brasileña, pero las asimetrías científicas históricas persisten.

Alcance de las células madre derivadas de tejido adiposo / Scope of stem cells derived from adipose tissue

Introducción: En el tejido adiposo se han identificado células madre mesenquimales con capacidad autorrenovadora y multipotencial. Mediante digestión enzimática y centrifugado del lipoaspirado se libera una población heterogénea de células denominada fracción vascular estromal, con innumerables potencialidades terapéuticas en el campo de la medicina regenerativa. Objetivo: Actualizar el alcance de las células madre derivadas de tejido adiposo en la terapia regenerativa. Método: Se revisaron 38 artículos entre los años 2000 y 2019 en las bases de datos Scielo, ScienceDirect, Medline y Pubmed. Desarrollo: Las células de la fracción vascular estromal se caracterizan por su capacidad de generar tejido adiposo y vasos sanguíneos, y por la producción de factores de crecimiento que ayudan en la supervivencia de los adipocitos y la formación de una red vascular. El principal mecanismo de acción de las células madre derivadas de tejido adiposo parece deberse a su acción paracrina y a la sinergia con células endoteliales. En el campo de la medicina regenerativa se han utilizado en el tratamiento de cicatrices patológicas y de fibrosis deformantes con impotencia funcional, en las reconstrucciones de secuelas por cáncer y en el cierre precoz de zonas cruentas. Conclusiones: La lipotransferencia es un procedimiento con un mínimo de complicaciones que constituye una de las opciones terapéuticas más empleadas para corregir defectos en los tejidos, debido a que no solo es un medio de relleno, sino que también permite la regeneración y restauración tisular. La presencia de células madre en el tejido adiposo, unido a su accesibilidad, disponibilidad e histocompatibilidad, ha motivado su aplicación cada vez más expandida en la medicina estética, reconstructiva y regenerativa(AU)

Introduction: Mesenchymal stem cells with self-renewing and multipotential capacity have been identified in adipose tissue. By means of enzymatic digestion and centrifugation of the lipoaspirate a heterogeneous population of cells called vascular stromal fraction is released. It has innumerable therapeutic potentialities in the field of regenerative medicine. Objective: To update the scope of stem cells derived from adipose tissue in regenerative therapy. Method: 38 articles published between 2000 and 2019 in the Scielo, ScienceDirect, Medline and Pubmed databases were reviewed. Development: The cells of the vascular stromal fraction are characterized by generating adipose tissue and blood vessels and by the production of growth factors that help in the survival of adipocytes and the formation of a vascular network. The main mechanism of action of stem cells derived from adipose tissue appears to be due to their paracrine action and synergy with endothelial cells. Stem cells derived from adipose tissue have been used in regenerative medicine for the treatment of pathological scars and deforming fibrosis with functional impotence, in the reconstruction of cancer sequelae and in the early closure of bloody areas. Conclusions: Lipotransfer is a procedure with a minimum of complications that constitutes one of the most widely used therapeutic options to correct tissue defects, since it is not only a filling medium, but also allows tissue regeneration and restoration. The presence of stem cells in adipose tissue, together with their accessibility, availability and histocompatibility, has motivated their increasingly widespread application in aesthetic, reconstructive and regenerative medicine(AU)

Roles of ten eleven translocation proteins family and 5-hydroxymethylcytosine in epigenetic regulation of stem cells and regenerative medicine / 北京大学学报(医学版)

The methylation of cytosine is one of the most fundamental epigenetic modifications in mammalian genomes, and is involved in multiple crucial processes including gene expression, cell differentiation, embryo development and oncogenesis. In the past, DNA methylation was thought to be an irreversible process, which could only be diluted passively through DNA replication. It is now becoming increa-singly obvious that DNA demethylation can be an active process and plays a crucial role in biological processes. Ten eleven translocation (TET) proteins are the key factors modulating DNA demethylation. This family contains three members: TET1, TET2 and TET3. Although three TET proteins have relatively conserved catalytic domains, their roles in organisms are not repeated, and their expression has significant cell/organ specificity. TET1 is mainly expressed in embryonic stem cells, TET2 is mainly expressed in hematopoietic system, and TET3 is widely expressed in cerebellum, cortex and hippocampus. This family catalyzes 5-methylcytosine to 5-hydroxymethylcytosine and other oxidative products, reactivates silenced-gene expression, in turn maintains stem cell pluripotency and regulates lineage specification. With the development of tissue engineering, organ transplantation, autologous tissue transplantation and artificial prosthesis have been widely used in clinical treatment, but these technologies have limitations. Regenerative medicine, which uses stem cells and stem cell related factors for treatment, may provide alternative therapeutic strategies for multiple diseases. Among all kinds of human stem cells, adipose-derived stem cells (ADSCs) are the most prospective stem cell lineage since they have no ethical issues and can be easily obtained with large quantities. To date, ADSCs have been shown to have strong proli-feration capacity, secrete numerous soluble factors and have multipotent differentiation ability. However, the underlying mechanism of the proliferation, secretion, acquired pluripotency, and lineage specific differentiation of ADSCs are still largely unknown. Some studies have explored the role of epigenetic regulation and TET protein in embryonic stem cells, but little is known about its role in ADSCs. By studying the roles of TET proteins and 5-hydroxymethylcytosine in ADSCs, we could provide new theoretical foundation for the clinical application of ADSCs and the stem cell-based therapy. In the future, combined with bioprinting technology, ADSCs may be used in tissue and organ regeneration, plastic surgery reconstruction and other broader fields.

Obtención y caracterización de células madre mesenquimales adultas de la pulpa dental humana / Obtaining and characterizing adult mesenchymal stem cells from human dental pulp

El presente trabajo de investigación tiene como objetivo principal el aislar, expandir y caracterizar inmunofenotípicamente células madre mesenquimales de la pulpa dental humana, según los criterios mínimos propuestos por The International Society for Cellular Therapy (ISCT), como así también establecer la puesta a punto de las técnicas y protocolos de procedimientos para tal fin. Los cultivos fueron permanentemente monitoreados mediante microscopio invertido con contraste de fase y la inmunotipificación fue realizada por citometría de flujo (AU)

Human Umbilical Cord Mesenchymal Stem Cells Over Platelet Rich Fibrin Scaffold for Mandibular Cartilage Defects Regenerative Medicine

ABSTRACT Objective: To evaluate the regeneration of mandibular cartilage defect after implantation of human umbilical cord mesenchymal stem cells (hUCMSC) over platelet rich fibrin (PRF) as scaffold. Material and Methods: 20 male Wistar rats were randomly divided into four experimental groups consisting of: a control group featuring untreated mandibular defects (C), experimental groups whose mandibular defects were implanted with hUCMSC (E1), mandibular defects implanted with PRF (E2), mandibular defects implanted with hUCMSC and PRF scaffold (E3). The subjects were sacrificed after six weeks of observation for immunohistochemical examination in order to evaluate the expression of Ki67, Sox9, FGF 18, type 2 collagen, and aggrecan, in addition to histology examination to evaluate chondrocyte number and cartilage thickness. Data was analyzed with univariate analysis (ANOVA). Results: The implantation of hUCMSC and PRF scaffold proved capable of regenerating mandibular cartilage defect through the expression of FGF 18, Sox9, Ki67, chondrosis counts, type 2 collagen, aggrecan, and cartilage thickness. The regeneration were significantly higher in group E3. Conclusion: Human umbilical cord mesenchymal stem cells in platelet rich fibrin scaffold proved capable of regenerating mandibular cartilage defect.

Papila Apical Dentaria como fuente de Células Madre: Relato del Caso / Papila Apical Dentária como Fonte de Células Tronco: Relato de Caso / Dental Apical Papila Stem Cell: Case Report

Las células madre mesenquimales (MSCs) son células madre adultas que tienen la capacidad de diferenciarse en varios tipos de células. Una rica fuente de células madre mesenquimales puede ser obtenida de tejidos dentales como la papila apical. El objetivo de este trabajo fue extraer las células madre de la papila apical de terceros molares humano para mirar su viabilidad de usarse en la práctica clínica. La de separación celular con Stro-1 y estudio de cinéticas fueron realizados. Como resultado, esas células, presentaron alta tasa de proliferación, formación de colonias y fácil acceso. Concluimos que el uso de células madre obtenidas de diente puede ser una buena alternativa por ser de fácil acceso, alta viabilidad celular y expresión positiva para marcadores celulares mesenquimales. La regeneración tisular o la formación de estructuras craneofaciales constituyen el futuro de la medicina regenerativa, ofreciendo una posibilidad para el tratamiento de malformaciones congénitas, traumas y otras enfermedades.

As células tronco mesenquimais (CTMs) são células-tronco adultas que têm a capacidade de diferenciar em vários tipos de células. Uma rica fonte de células tronco mesenquimais pode ser obtida de tecidos dentais como a papila apical. O objetivo deste trabalho foi extrair as células tronco da papila apical de terceiros molares humano para ver sua viabilidade de ser usado na prática clinica. Teste separação celular com Stro-1 e estudo de cinéticas foram realizados. Como resultado essas células apresentaram alta taxa de proliferação, formação de colônias e de fácil acesso. Concluímos que o uso de células tronco obtidas de dente pode ser uma boa alternativa por ser fácil acesso, alta viabilidade celular e expressão positiva para marcadores celulares mesenquimais. A regeneração tecidual ou a formação de novo de estruturas craniofaciais é o futuro da medicina regenerativa, oferecendo uma possibilidade para tratamento de malformações congênitas, traumas e outras doenças.

Mesenchymal stem cells (MSCs) are adult stem cells that have the ability to diffe-rentiate into various cell types. A rich source of mesenchymal stem cells can be obtained from dental tissues such as the apical papilla. The objective of this work was to extract stem cells from the apical papilla of third human molars to see its feasibility to be used in clinical practice. Testing of cell separation with Stro-1 and study of kinetics were performed. As a result, these cells had a high rate of pro-liferation, formation of colonies and easy access. We conclude that the use of stem cells obtained from teeth can be a good alternative because they are easy to ac-cess, high cell viability and positive ex-pression for mesenchymal cell markers. Tissue regeneration or new formation of craniofacial structures is the future of re-generative medicine, offering a possibili-ty for treatment of congenital malforma-tions, traumas and other diseases.

Obtención de plasma rico en plaquetas (PRP) en el Laboratorio de Terapia Celular para uso como herramienta terapéutica en medicina regenerativa / Obtaining platelet rich plasma (PRP) in the Cell Therapy Laboratory for use as a therapeutic tool in regenerative medicine

Platelet rich plasma (PRP) is used to speed up tissue repair. Despite its widespread use, the therapeutic application of PRP generates controversies in clinical results due to the variability in methods of obtaining the different preparations and differences between the components of different types of PRP, so it's recommended to mention the type of platelet preparation used. In this article, we describe technical and biologics characteristics of our platelet product, and we compare them to different commercial preparations described in order to validate their clinical use. Our results determine that the preparation can be considered a platelet rich plasma with biological activity in vivo and in vitro, which supports its use as a valid therapeutic tool, alternative to products currently available in Regenerative Medicine. (AU)

Research progress on the effect of surface charge of biomaterials on bone formation / 生物医学工程学杂志

With the continuous progress of materials science and biology, the significance of biomaterials with dual characteristics of materials science and biology is keeping on increasing. Nowadays, more and more biomaterials are being used in tissue engineering, pharmaceutical engineering and regenerative medicine. In repairing bone defects caused by trauma, tumor invasion, congenital malformation and other factors, a variety of biomaterials have emerged with different characteristics, such as surface charge, surface wettability, surface composition, immune regulation and so on, leading to significant differences in repair effects. This paper mainly discusses the influence of surface charge of biomaterials on bone formation and the methods of introducing surface charge, aiming to promote bone formation by changing the charge distribution on the surface of the biomaterials to serve the clinical treatment better.