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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.

The study comparing the bone regenerative capacity in an experimental model of cranial bone defects in rats, into 3 groups: G1: bone defects irradiated with photobiomodulation; G2: Biosilicate + photobiomodulation and G3: Biosilicate and Spongin + photobiomodulation. Histocompatibility and bone responses were performed after 15 and 45 days of implantation. Histological analysis demonstrated that photobiomodulation irradiated animals presented an increased amount of newly formed over time. Histomorphometry showed higher values for bone volume for G3 and G1, higher values for osteoid volume and number of osteoblasts observed for G3 compared to G2. TGF-β immunolabelling was higher for G2. The values found for VEGF were higher for biosilicate (with or without spongin) 15 days of implantation with an increased difference being observed for G1, 45 days after surgery. In conclusion, the stimulus provided by photobiomodulation associated to the biomimetic composite increased bone formation in the cranial bone defect in rats. Consequently, these data highlight the potential of the introduction of spongin into biosilicate and irradiated with photobiomodulation to improve the biological performance for bone regeneration applications. El estudio comparó la capacidad de regeneración ósea en un modelo experimental de defectos óseos craneales en ratas, en 3 grupos: G1: defectos óseos irradiados con fotobiomodulación; G2: Biosilicato + fotobiomodulación y G3: Biosilicato y Spongin + fotobiomodulación. La histocompatibilidad y las respuestas óseas se realizaron a los 15 y 45 días de la implantación. El análisis histológico demostró que los animales irradiados con fotobiomodulación presentaron una mayor cantidad de recién formados con el tiempo. La histomorfometría mostró valores más altos para el volumen óseo para G3 y G1, valores más altos para el volumen osteoide y el número de osteoblastos observados para G3 en comparación con G2. El inmunomarcaje de TGF-β fue mayor para G2. Los valores encontrados para VEGF fueron mayores para el biosilicato (con o sin esponja) a los 15 días de la implantación, observándose una mayor diferencia para G1, 45 días después de la cirugía. En conclusión, el estímulo proporcionado por la fotobiomodulación asociada al compuesto biomimético aumentó la formación de hueso en el defecto óseo craneal en ratas. En consecuencia, estos datos destacan el potencial de la introducción de espongina en biosilicato e irradiado con fotobiomodulación para mejorar el rendimiento biológico para aplicaciones de regeneración ósea. O estudo comparou a capacidade regenerativa óssea em modelo experimental de defeitos ósseos cranianos em ratos, em 3 grupos: G1: defeitos ósseos irradiados com fotobiomodulação; G2: Biosilicato + fotobiomodulação e G3: Biosilicato e esponja marinha + fotobiomodulação. A histocompatibilidade e as respostas ósseas foram realizadas após 15 e 45 dias de implantação. A análise histológica demonstrou que os animais irradiados com fotobiomodulação apresentaram um aumento da quantidade de neoformados ao longo do tempo. A histomorfometria mostrou maiores valores de volume ósseo para G3 e G1, maiores valores de volume de osteóide e número de osteoblastos observados para G3 em relação ao G2. A imunomarcação de TGF-β foi maior para G2. Os valores encontrados para VEGF foram maiores para o biosilicato (com ou sem esponja marinha) 15 dias após o implante, com diferença aumentada sendo observada para o G1, 45 dias após a cirurgia. Em conclusão, o estímulo fornecido pela fotobiomodulação associada ao compósito biomimético aumentou a formação óssea no defeito ósseo craniano em ratos. Consequentemente, esses dados destacam o potencial da introdução da esponja marinha no biosilicato e irradiada com fotobiomodulação para melhorar o desempenho biológico para aplicações de regeneração óssea.

Federal University of Par?. Institute of Biological Sciences. Bel?m, PA, Brazil. Federal University of Par?. Institute of Biological Sciences. Bel?m, PA, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Microscopia. Ananindeua, PA, Brasil. Federal University of Par?. Department of Mechanical Engineering. Bel?m, PA, Brazil. Federal University of Par?. Institute of Biological Sciences. Bel?m, PA, Brazil. Federal University of Par?. Department of Nutrition. Bel?m, PA, Brazil. Campinas State University. National Institute of Science and Technology in Biofabrication. Chemical Engineering Department. Campinas, SP, Brazil. Federal University of Par?. Institute of Biological Sciences. Bel?m, PA, Brazil / Campinas State University. National Institute of Science and Technology in Biofabrication. Chemical Engineering Department. Campinas, SP, Brazil. Despite the many advances in the field of regenerative medicine, the use of biomaterials to repair the cartilaginous tissue's traumatic injuries is still a challenge. Based on that, this research focuses on the semi-interpenetrating polymeric scaffolds (SIPNs) based PLLA and PHEMA. The material was produced in the solvent absence as a strategy to outline the critical limitations of hydrophilicity and the lack of biological interaction of biomaterials with the surrounding tissues. To this end, the thermal properties and chemical structure were characterized using thermogravimetric analysis and spectroscopy in the Fourier transform infrared. Besides, we assessed porosity and tissue interactions by scanning electron microscopy, and the influence of this in the swelling capacity tests. In vitro and in vivo assays and histological analysis were developed to assess the biocompatibility of SIPNs scaffolds. The results showed good thermal stability, porosity in the range of 53.73 to 94.34??m, absence of toxicity, and excellent in vitro cell adhesion and growth. The biomaterial also promoted a great template for cell migration and spreading in vivo, with high cartilaginous tissue remodeling. SIPNs scaffolds demonstrated its biocompatibility and potential use in tissue engineering.

Made available in DSpace on 2021-06-25T12:30:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-31 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fibronectin (FN)-loaded nanofiber scaffolds were developed and assessed concerning their bioactive potential on human apical papilla cells (hAPCs). First, random (NR) and aligned (NA) nanofiber scaffolds of polycaprolactone (PCL) were obtained by electrospinning technique and their biological properties were evaluated. The best formulations of NR and NA were loaded with 0, 5, or 10 mu g/ml of FN and their bioactivity was assessed. Finally, FN-loaded NR and NA tubular scaffolds were prepared and their chemotactic potential was analyzed using an in vitro model to mimic the pulp regeneration of teeth with incomplete root formation. All scaffolds tested were cytocompatible. However, NR and NA based on 10% PCL promoted the highest hAPCs proliferation, adhesion and spreading. Polygonal and elongated cells were observed on NR and NA, respectively. The higher the concentration of FN added to the scaffolds, greater cell migration, viability, proliferation, adhesion and spreading, as well as collagen synthesis and gene expression (ITGA5, ITGAV, COL1A1, COL3A1). In addition, tubular scaffolds with NA loaded with FN (10 mu g/ml) showed the highest chemotactic potential on hAPCs. It was concluded that FN-loaded NA scaffolds may be an interesting biomaterial to promote hAPCs-mediated pulp regeneration of endodontically compromised teeth with incomplete root formation. Univ Estadual Paulista, Araraquara Sch Dent, Dept Dent Mat & Prosthodont, Araraquara, SP, Brazil Univ Sao Paulo, Bauru Sch Dent, Dept Operat Dent Endodont & Dent Mat, Bauru, SP, Brazil Sao Paulo State Univ, Araraquara Sch Dent, Dept Orthodont & Pediat Dent, Araraquara, SP, Brazil Sao Paulo State Univ, Araraquara Sch Dent, Dept Physiol & Pathol, Humaita St 1680, BR-14801903 Araraquara, SP, Brazil Univ Estadual Paulista, Araraquara Sch Dent, Dept Dent Mat & Prosthodont, Araraquara, SP, Brazil Sao Paulo State Univ, Araraquara Sch Dent, Dept Orthodont & Pediat Dent, Araraquara, SP, Brazil Sao Paulo State Univ, Araraquara Sch Dent, Dept Physiol & Pathol, Humaita St 1680, BR-14801903 Araraquara, SP, Brazil CNPq: 302047/2019-0 CNPq: 408721/2018-9 FAPESP: 2017/14210-8 FAPESP: 2017/22739-9

The importance of the hoof to the horse health is clear, and the current knowledge regarding the cellular aspects of hoof keratinocytes is poor. Studies on equine keratinocyte culture are scarce. Developing keratinocyte cultures in vitro is a condition for studies on molecular biology, cell growth and differentiation. Some methods have already been established, such as those for skin keratinocyte culture. However, few methodologies are found for lamellar keratinocytes. The objective of this study was to standardize the equine hoof keratinocyte isolation and cultivation, and then characterize the cell immunophenotype. For this, the primary culture method used was through explants obtained from three regions of the equine hoof (medial dorsal, dorsal, and lateral dorsal). After the cell isolation and cultivation, the cell culture and its explants were stained with anti-pan cytokeratin (pan-CK) (AE1/AE3), vimentin (V9), p63 (4A4), and Ki-67 (MIB-1) antibodies. Cells were grown to third passage, were positive for pan-CK, p63 and Ki-67, and few cells had vimentin positive expression. As for the explants, the epidermal laminae were not stained for vimentin or Ki-67. However, some cells presented positive pan-CK and p63 expression. This study demonstrated the viability of lamellar explants of equine hooves as a form of isolating keratinocytes in primary cultures, as well as characterized the proliferation ability of such keratinocytes in monolayers. RESUMO: É notória a importância do casco na saúde dos equinos, mas o conhecimento em nível celular é pouco entendido. Estudos envolvendo o cultivo de queratinócitos equinos são escassos. Sabe-se que o desenvolvimento de cultivos de queratinócitos in vitro é uma condição para estudos sobre a biologia molecular, crescimento e diferenciação celular. Alguns métodos já estão estabelecidos, como para cultivo de queratinócitos de pele, mas poucas metodologias são encontradas para queratinócitos lamelares. O objetivo desse estudo foi padronizar o cultivo de queratinócitos provenientes de casco equino visando futuramente associar ao estudo da medicina regenerativa para assim estabelecer um modelo experimental in vitro e indicar o uso criterioso de terapias regenerativas para a laminite equina. Desta forma, o cultivo em monocamada e a caracterização de queratinócitos lamelares foram realizados. Para isso, o método de cultura primária utilizado foi através de explantes obtidos de três regiões do casco (dorso-medial, dorsal e dorso-lateral). As células foram caracterizadas para os marcadores anti pan-cytokeratin (AE1/AE3), vimentin (V9), p63 (4A4) e Ki-67 (MIB-1) nos cultivos e nos explantes. As células foram cultivadas até terceira passagem, tendo marcação positiva para pan-CK, p63 e Ki-67 e fraca marcação para vimentina. Já as lâminas epidermais não tiveram marcação de vimentin e Ki-67, porém marcaram acentuadamente para pan-CK e p63. Este estudo demonstrou a exiquibilidade do uso de explantes lamelares do casco de equinos, como forma de isolamento de queratinócitos em cultivos primários, bem como caracterizou a habilidade de proliferação desses queratinócitos em monocamada.

Biodegradable membranes for guided bone regeneration, made of polycaprolactone, obtained by electrospinning, incorporated with different nanocomposite ratios of cellulose nanocrystals and Biosilicate®, have been manufactured, with improved mechanical and osteogenic properties. As fast vascularization strategy, a suturable biomimetic graft obtained by fusion of electrospun membranes was fabricated, with porous patterns obtained by laser micromachining to allow migration of endothelial cells to the bone graft. The porous patterns created on the suturable grafts allowed the endothelial cells to migrate to the 3D culture of the osteoblasts in gelatin methacryloyl (GelMA), and 3D structures were observed. Therefore, this strategy can be used to improve the size and survival of biofabricated bone implants, accelerating the clinical translation of bone tissue engineering.; Des membranes biodégradables en polycaprolactone pour la régénération osseuse guidée, obtenues par electrospinning, incorporés avec différents rapports de nanocomposites de nanocristaux de cellulose et du Biosilicate®, ont été fabriquées, avec propriétés mécaniques et ostéogéniques améliorés. En tant que stratégie de vascularisation rapide, un greffon biomimétique suturable obtenue par fusion de membranes électrofilées a été fabriqué, avec des motifs poreux obtenus par micro- usinage au laser pour permettre la migration des cellules endothéliales vers le greffon osseux. Les motifs poreux créés sur les greffes suturables ont permis aux cellules endothéliales migrer vers la culture 3D des ostéoblastes dans des hydrogels en gélatine méthacryloyl (GelMA), et des structures 3D ont été observées. Par conséquent, cette stratégie peut être utilisée pour améliorer la taille et la survie des implants osseux biofabriqués, en accélérant la traduction clinique de l'ingénierie du tissu osseux.

Cardiovascular diseases are the major cause of death worldwide. The heart has limited capacity of regeneration, therefore, transplantation is the only solution in some cases despite presenting many disadvantages. Tissue engineering has been considered the ideal strategy for regenerative medicine in cardiology. It is an interdisciplinary field combining many techniques that aim to maintain, regenerate or replace a tissue or organ. The main approach of cardiac tissue engineering is to create cardiac grafts, either whole heart substitutes or tissues that can be efficiently implanted in the organism, regenerating the tissue and giving rise to a fully functional heart, without causing side effects, such as immunogenicity. In this review, we systematically present and compare the techniques that have drawn the most attention in this field and that generally have focused on four important issues: the scaffold material selection, the scaffold material production, cellular selection and in vitro cell culture. Many studies used several techniques that are herein presented, including biopolymers, decellularization and bioreactors, and made significant advances, either seeking a graft or an entire bioartificial heart. However, much work remains to better understand and improve existing techniques, to develop robust, efficient and efficacious methods. RESUMO Doenças cardiovasculares são responsáveis pelo maior número de mortes no mundo. O coração possui capacidade de regeneração limitada, e o transplante, por consequência, representa a única solução em alguns casos, apresentando várias desvantagens. A engenharia de tecidos tem sido considerada a estratégia ideal para a medicina cardíaca regenerativa. Trata-se de uma área interdisciplinar, que combina muitas técnicas as quais buscam manter, regenerar ou substituir um tecido ou órgão. A abordagem principal da engenharia de tecidos cardíacos é criar enxertos cardíacos, sejam substitutos do coração inteiro ou de tecidos que podem ser implantados de forma eficiente no organismo, regenerando o tecido e dando origem a um coração completamente funcional, sem desencadear efeitos colaterais, como imunogenicidade. Nesta revisão, apresentase e compara-se sistematicamente as técnicas que ganharam mais atenção nesta área e que geralmente focam em quatro assuntos importantes: seleção do material a ser utilizado como enxerto, produção do material, seleção das células e cultura de células in vitro. Muitos estudos, fazendo uso de várias das técnicas aqui apresentadas, incluindo biopolímeros, descelularização e biorreatores, têm apresentado avanços significativos, seja para obter um enxerto ou um coração bioartifical inteiro. No entanto, ainda resta um grande esforço para entender e melhorar as técnicas existentes, para desenvolver métodos robustos, eficientes e eficazes.

Made available in DSpace on 2018-12-11T17:19:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-06-01 Introduction: The improvement of biomaterials capable of driving the regeneration of the pulp-dentin complex mediated by resident cells is the goal of regenerative dentistry. In the present investigation, a chitosan scaffold (CHSC) that released bioactive concentrations of simvastatin (SIM) was tested, aimed at the development of a cell-free tissue engineering system. Methods: First, we performed a dose-response assay to select the bioactive dose of SIM capable of inducing an odontoblastic phenotype in dental pulp cells (DPCs); after which we evaluated the synergistic effect of this dosage with the CHSC/DPC construct. SIM at 1.0 μmol/L (CHSC-SIM1.0) and 0.5 μmol/L were incorporated into the CHSC, and cell viability, adhesion, and calcium deposition were evaluated. Finally, we assessed the biomaterials in an artificial pulp chamber/3-dimensional culture model to simulate the cell-free approach in vitro. Results: SIM at 0.1 μmol/L was selected as the bioactive dose. This drug was capable of strongly inducing an odontoblastic phenotype on the DPC/CHSC construct. The incorporation of SIM into CHSC had no deleterious effect on cell viability and adhesion to the scaffold structure. CHSC-SIM1.0 led to significantly higher calcium-rich matrix deposition on scaffold/dentin disc assay compared with the control (CHSC). This biomaterial induced the migration of DPCs from a 3-dimensional culture to its surface as well as stimulated significantly higher expressions of alkaline phosphatase, collagen type 1 alpha 1, dentin matrix acidic phosphoprotein 1, and dentin sialophosphoprotein on 3-dimensional–cultured DPCs than on those in contact with CHSC. Conclusions: CHSC-SIM1.0 scaffold was capable of increasing the chemotaxis and regenerative potential of DPCs. Department of Operative Dentistry Endondontics and Dental Materials Bauru School of Dentistry University of São Paulo-USP Department of Physiology and Pathology Araraquara School of Dentistry Universidade Estadual Paulista–UNESP Department of Orthodontics and Pediatric Dentistry Araraquara School of Dentistry Universidade Estadual Paulista–UNESP Department of Physiology and Pathology Araraquara School of Dentistry Universidade Estadual Paulista–UNESP Department of Orthodontics and Pediatric Dentistry Araraquara School of Dentistry Universidade Estadual Paulista–UNESP

Biodegradable membranes for guided bone regeneration, made of polycaprolactone, obtained by electrospinning, incorporated with different nanocomposite ratios of cellulose nanocrystals and Biosilicate®, have been manufactured, with improved mechanical and osteogenic properties. As fast vascularization strategy, a suturable biomimetic graft obtained by fusion of electrospun membranes was fabricated, with porous patterns obtained by laser micromachining to allow migration of endothelial cells to the bone graft. The porous patterns created on the suturable grafts allowed the endothelial cells to migrate to the 3D culture of the osteoblasts in gelatin methacryloyl (GelMA), and 3D structures were observed. Therefore, this strategy can be used to improve the size and survival of biofabricated bone implants, accelerating the clinical translation of bone tissue engineering., Des membranes biodégradables en polycaprolactone pour la régénération osseuse guidée, obtenues par electrospinning, incorporés avec différents rapports de nanocomposites de nanocristaux de cellulose et du Biosilicate®, ont été fabriquées, avec propriétés mécaniques et ostéogéniques améliorés. En tant que stratégie de vascularisation rapide, un greffon biomimétique suturable obtenue par fusion de membranes électrofilées a été fabriqué, avec des motifs poreux obtenus par micro- usinage au laser pour permettre la migration des cellules endothéliales vers le greffon osseux. Les motifs poreux créés sur les greffes suturables ont permis aux cellules endothéliales migrer vers la culture 3D des ostéoblastes dans des hydrogels en gélatine méthacryloyl (GelMA), et des structures 3D ont été observées. Par conséquent, cette stratégie peut être utilisée pour améliorer la taille et la survie des implants osseux biofabriqués, en accélérant la traduction clinique de l'ingénierie du tissu osseux.

Regenerative therapies have been widely developed in dentistry and it is important to incorporate dentists’ knowledge of these new therapies into the dental clinic routine. This study reviewed the literature on regenerative therapies and clinical applications. Tissue engineering has contributed to changes in the paradigm of restorative health sciences. Its pillars underpin the techniques of tissue and organ regeneration. Despite the majority of studies in this field being in vitro, a range of preclinical studies and methodologies has been formed using these principles and they are already being used on humans. The use of platelet-rich plasma and platelet-rich fibrin in surgery as natural scaffolds for the reestablishment of bone and periodontal tissue are often reported in the literature and clinical trials using this approach have shown promising results. Stem cells from autologous dental pulp have been successfully applied in bone tissue regeneration using natural collagen scaffold in humans. In addition, revascularization of the root canal already appears in the literature as a promising alternative to apexification. The principle behind this therapy is the use of the blood clot as a scaffold and the migration of stem cells of the apical papilla to regenerate the dental pulp organ. Final considerations: Although still in the early stages, regenerative therapies can now be used in dental practice. Knowledge of the principles governing these therapies should be understood by the dentist for use in clinical practice. RESUMO Terapias regenerativas vem sendo amplamente desenvolvidas na odontologia e o conhecimento destas novas terapias por parte dos dentistas é importante para que elas sejam incorporadas na rotina clínica odontológica. Assim, este estudo revisou a literatura acerca das terapias regenerativas e suas aplicações clínicas. A engenharia tecidual tem contribuído na mudança do paradigma restaurador das ciências da saúde. Seus pilares embasam as técnicas de regeneração de tecidos e órgãos. Apesar da grande maioria dos estudos neste campo ser in vitro, uma gama de metodologias pré-clínicas foi consolidada e estudos utilizando estes princípios já estão sendo empregados em humanos. A utilização de plasma rico em plaquetas e plasma rico em fibrina como scaffolds naturais em cirurgias para reestabelecimento de tecido ósseo e periodontal são frequentemente relatadas na literatura e ensaios clínicos utilizando esta abordagem demonstram resultados promissores. Células-tronco da polpa dental autólogas já foram aplicadas com sucesso na regeneração de tecido ósseo utilizando scaffold naturais de colágeno em humanos. Além disto, a revascularização do canal radicular já aparece na literatura como uma alternativa promissora frente a opção de apecificação do canal radicular. Esta terapia utiliza como princípio o coágulo sanguíneo como scaffold e a migração das células-tronco da papila apical para regenerar o órgão pulpar. Considerações finais: Apesar de incipientes, as terapias regenerativas já podem ser utilizadas na prática clínica odontológica. O conhecimento dos princípios que regem estas terapias deve ser compreendido pelo dentista para que sejam utilizadas na prática clínica.

© 2016 by the author. Scaffolds are physical substrates for cell attachment, proliferation, and differentiation, ultimately leading to the regeneration of tissues. They must be designed according to specific biomechanical requirements, i.e., certain standards in terms of mechanical properties, surface characteristics, porosity, degradability, and biocompatibility. The optimal design of a scaffold for a specific tissue strongly depends on both materials and manufacturing processes, as well as surface treatment. Polymeric scaffolds reinforced with electro-active particles could play a key role in tissue engineering by modulating cell proliferation and differentiation. This paper investigates the use of an extrusion-based additive manufacturing system to produce poly(ε-caprolactone) (PCL)/pristine graphene scaffolds for bone tissue applications and the influence of chemical surface modification on their biological behaviour. Scaffolds with the same architecture but different concentrations of pristine graphene were evaluated from surface property and biological points of view. Results show that the addition of pristine graphene had a positive impact on cell viability and proliferation, and that surface modification leads to improved cell response.

PURPOSE: To evaluate the capacity of natural latex membrane to accelerate and improve the regeneration quality of the of rat sciatic nerves. METHODS: Forty male adult Wistar rats were used, anesthetized and operated to cut the sciatic nerve and receive an autograft or a conduit made with a membrane derived from natural latex (Hevea brasiliensis). Four or eight weeks after surgery, to investigate motor nerve recovery, we analyzed the neurological function by walking pattern (footprints analysis and computerized treadmill), electrophysiological evaluation and histological analysis of regenerated nerve (autologous nerve graft or tissue cables between the nerve stumps), and anterior tibial and gastrocnemius muscles. RESULTS: All functional and morphological analysis showed that the rats transplanted with latex conduit had a better neurological recovery than those operated with autologous nerve: quality of footprints, performance on treadmill (p

PURPOSE: To evaluate the implant of human adipose derived stem cells (ADSC) delivered in hyaluronic acid gel (HA), injected in the subcutaneous of athymic mice. METHODS: Control implants -HA plus culture media was injected in the subcutaneous of the left sub scapular area of 12 athymic mice. ADSC implants: HA plus ADSC suspended in culture media was injected in the subcutaneous, at the contra lateral area, of the same animals. With eight weeks, animals were sacrificed and the recovered implants were processed for extraction of genomic DNA, and histological study by hematoxilin-eosin staining and immunufluorescence using anti human vimentin and anti von Willebrand factor antibodies. RESULTS: Controls: Not visualized at the injection site. An amorphous substance was observed in hematoxilin-eosin stained sections. Human vimentin and anti von Willebrand factor were not detected. No human DNA was detected. ADSC implants - A plug was visible at the site of injection. Fusiform cells were observed in sections stained by hematoxilin- eosin and both human vimentin and anti von Willebrand factor were detected by immunofluorescence. The presence of human DNA was confirmed. CONCLUSION: The delivery of human adipose derived stem cells in preparations of hyaluronic acid assured cells engraftment at the site of injection. OBJETIVO: Avaliar o implante de células tronco do tecido adiposo humano (CTTAH) em gel de ácido hialurônico (AH), injetados no tecido subcutâneo de camundongos atímicos. MÉTODOS: Implantes controle - HA com meio de cultura foram injetados no tecido subcutâneo da região infraescapular esquerda de 12 camundongos atímicos. Implantes de CTTAH: HA com CTTAH suspensas em meio de cultura foi injetado no subcutâneo da região contra lateral, dos mesmos animais. Com oito semanas, os animais foram sacrificados e os implantes recuperados foram processados para extração de DNA genômico, estudo histológico por coloração por hematoxilina eosina e imnuoflurescência utilizando anticorpos anti vimentina humana e anti fator de von Willebrand. RESULTADOS: Controles - implantes não visualizados no local da injeção. Uma substância amorfa foi observada nos cortes corados por hematoxilina eosina. Vimentina humana e fator anti von Willebrand não foram identificados. DNA humano não foi detectado. Implantes de CTTAH - Uma massa era visível no local da injeção. Células fusiformes foram observadas nos corte corados com hematoxilina eosina. Tanto vimentina humana quanto fator de von Willebrand foram identificados pela imunofluorescência. A presença de DNA humano foi confirmada. CONCLUSÃO: O implante de células tronco do tecido adiposo humano em veículo de ácido hialurônico gel assegurou a manutenção das células no local do implante.