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Development of an ideal biomaterial for clinical use is one of the main objectives of current research in tissue engineering. Marine-origin polysaccharides, in particular agaroses, have been widely explored as scaffolds for tissue engineering. We previously developed a biomaterial based on a combination of agarose with fibrin, that was successfully translated to clinical practice. However, in search of novel biomaterials with improved physical and biological properties, we have now generated new fibrin-agarose (FA) biomaterials using 5 different types of agaroses at 4 different concentrations. First, we evaluated the cytotoxic effects and the biomechanical properties of these biomaterials. Then, each bioartificial tissue was grafted in vivo and histological, histochemical and immunohistochemical analyses were performed after 30 days. Ex vivo evaluation showed high biocompatibility and differences in their biomechanical properties. In vivo, FA tissues were biocompatible at the systemic and local levels, and histological analyses showed that biointegration was associated to a pro-regenerative process with M2-type CD206-positive macrophages. These results confirm the biocompatibility of FA biomaterials and support their clinical use for the generation of human tissues by tissue engineering, with the possibility of selecting specific agarose types and concentrations for applications requiring precise biomechanical properties and in vivo reabsorption times.
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Materiais Biocompatíveis , Fibrina , Humanos , Sefarose/química , Fibrina/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Engenharia Tecidual/métodos , Hidrogéis/química , Alicerces Teciduais/químicaRESUMO
OBJECTIVE: The aim of this study was to generate novel models of bioartificial human oral mucosa with increased vascularization potential for future use as an advanced therapies medicinal product, by using different vascular and mesenchymal stem cell sources. BACKGROUND: Oral mucosa substitutes could contribute to the clinical treatment of complex diseases affecting the oral cavity. Although several models of artificial oral mucosa have been described, biointegration is a major issue that could be favored by the generation of novel substitutes with increased vascularization potential once grafted in vivo. METHODS: Three types of mesenchymal stem cells (MSCs) were obtained from adipose tissue, bone marrow, and dental pulp, and their in vitro potential was evaluated by inducing differentiation to the endothelial lineage using conditioning media. Then, 3D models of human artificial oral mucosa were generated using biocompatible fibrin-agarose biomaterials combined with human oral mucosa fibroblasts and each type of MSC before and after induction to the endothelial lineage, using human umbilical vein endothelial cells (HUVEC) as controls. The vascularization potential of each oral mucosa substitute was assessed in vitro and in vivo in nude mice. RESULTS: In vitro induction of MSCs kept in culture was able to increase the expression of VEGF, CD31, and vWF endothelial markers, especially in bone marrow and dental pulp-MSCs, and numerous proteins with a role in vasculogenesis become overexpressed. Then, in vivo grafting resulted in a significant increase in blood vessels formation at the interface area between the graft and the host tissues, with significantly positive expression of VEGF, CD31, vWF, and CD34 as compared to negative controls, especially when pre-differentiated MSCs derived from bone marrow and dental pulp were used. In addition, a significantly higher number of cells committed to the endothelial lineage expressing the same endothelial markers were found within the bioartificial tissue. CONCLUSION: Our results suggest that the use of pre-differentiated MSCs could contribute to a rapid generation of a vascular network that may favor in vivo biointegration of bioengineered human oral mucosa substitutes.
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Células-Tronco Mesenquimais , Engenharia Tecidual , Animais , Diferenciação Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Nus , Mucosa Bucal/cirurgia , Neovascularização FisiológicaRESUMO
BACKGROUND: Tissue engineering (TE) constitutes a multidisciplinary field aiming to construct artificial tissues to regenerate end-stage organs. Its development has taken place since the last decade of the 20th century, entailing a clinical revolution. TE research groups have worked and shared relevant information in the mass media era. Thus, it would be interesting to study the online dimension of TE research and to compare it with traditional measures of scientific impact. OBJECTIVE: The objective of this study was to evaluate the online dimension of TE documents from 2012 to 2018 using metadata obtained from the Web of Science (WoS) and Altmetric and to develop a prediction equation for the impact of TE documents from altmetric scores. METHODS: We analyzed 10,112 TE documents through descriptive and statistical methods. First, the TE temporal evolution was exposed for WoS and 15 online platforms (news, blogs, policy, Twitter, patents, peer review, Weibo, Facebook, Wikipedia, Google, Reddit, F1000, Q&A, video, and Mendeley Readers). The 10 most cited TE original articles were ranked according to the normalized WoS citations and the normalized Altmetric Attention Score. Second, to better comprehend the TE online framework, correlation and factor analyses were performed based on the suitable results previously obtained for the Bartlett sphericity and Kaiser-Meyer-Olkin tests. Finally, the linear regression model was applied to elucidate the relation between academics and online media and to construct a prediction equation for TE from altmetrics data. RESULTS: TE dynamic shows an upward trend in WoS citations, Twitter, Mendeley Readers, and Altmetric Scores. However, WoS and Altmetric rankings for the most cited documents clearly differ. When compared, the best correlation results were obtained for Mendeley Readers and WoS (ρ=0.71). In addition, the factor analysis identified 6 factors that could explain the previously observed differences between academic institutions and the online platforms evaluated. At this point, the mathematical model constructed is able to predict and explain more than 40% of TE WoS citations from Altmetric scores. CONCLUSIONS: Scientific information related to the construction of bioartificial tissues increasingly reaches society through different online media. Because the focus of TE research importantly differs when the academic institutions and online platforms are compared, basic and clinical research groups, academic institutions, and health politicians should make a coordinated effort toward the design and implementation of adequate strategies for information diffusion and population health education.
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Fator de Impacto de Revistas , Mídias Sociais , Bibliometria , Humanos , Meios de Comunicação de Massa , Engenharia TecidualRESUMO
BACKGROUND: The students' conceptions of learning in postgraduate health science master studies are poorly understood. The aim of this study was to compare the factors influencing conceptions of learning in health sciences and non-health sciences students enrolled in postgraduate master programs in order to obtain information that may be useful for students and for future postgraduate programs. METHODS: A modified version of the Learning Inventory Conception Questionnaire (COLI) was used to compare students' conception learning factors in 131 students at the beginning of their postgraduate studies in health sciences, experimental sciences, arts and humanities and social sciences. RESULTS: The present study demonstrates that a set of factors may influence conception of learning of health sciences postgraduate students, with learning as gaining information, remembering, using, and understanding information, awareness of duty and social commitment being the most relevant. For these students, learning as a personal change, a process not bound by time or place or even as acquisition of professional competences, are less relevant. According to our results, this profile is not affected by gender differences. CONCLUSIONS: Our results show that the overall conceptions of learning differ among students of health sciences and non-health sciences (experimental sciences, arts and humanities and social sciences) master postgraduate programs. These finding are potentially useful to foster the learning process of HS students, because if they are metacognitively aware of their own conception or learning, they will be much better equipped to self-regulate their learning behavior in a postgraduate master program in health sciences.
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Educação Profissionalizante , Aprendizagem , Estudantes de Ciências da Saúde/psicologia , Adulto , Análise de Variância , Feminino , Ciências Humanas/educação , Humanos , Masculino , Competência Profissional , Reprodutibilidade dos Testes , Fatores Sexuais , Ciências Sociais/educação , Espanha , Estudantes/psicologia , Inquéritos e QuestionáriosRESUMO
BACKGROUND AIMS: Evaluation of cell viability is one of the most important steps of the quality control process for therapeutic use of cells. The aim of this study was to evaluate the long-term cell viability profile of human dental pulp stem cell (hDPSC) subcultures (beyond 10 passages) to determine which of these passages are suitable for clinical use and to identify the cell death processes that may occur in the last passages. METHODS: Four different cell viability assays were combined to determine the average cell viability levels at each cell passage: trypan blue exclusion test, water-soluble tetrazolium 1 (WST-1), LIVE/DEAD Viability/Cytotoxicity Kit and electron probe x-ray microanalysis (EPXMA). Apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and caspase 4 and BCL7C Western blotting, and cell proliferation was analyzed by WST-1 and proliferating cell nuclear antigen protein detection. RESULTS: hDPSCs showed high average cell viability levels from passages 11-14, with adequate cytoplasmic and mitochondrial functionality at these subcultures. A non-significant trend to decreased cell proliferation was found from passages 16-20. EPXMA and TUNEL analyses suggested that a pre-apoptotic process could be activated from passages 15-20 (P < 0.001), with a correlation with caspase 4 and BCL7C expression. CONCLUSIONS: hDPSCs corresponding to passages 11-14 show adequate cell function, proliferation and viability. These cells could be considered as potentially useful for clinical applications.
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Células-Tronco Adultas/metabolismo , Polpa Dentária/citologia , Fatores de Tempo , Células-Tronco Adultas/citologia , Apoptose , Proteínas Reguladoras de Apoptose , Caspases Iniciadoras/metabolismo , Técnicas de Cultura de Células , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Humanos , Marcação In Situ das Extremidades Cortadas , Proteínas dos Microfilamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Sais de Tetrazólio , Azul TripanoRESUMO
BACKGROUND: The students' motivation to learn basic sciences in health science curricula is poorly understood. The purpose of this study was to investigate the influence of different components of motivation (intrinsic motivation, self-determination, self-efficacy and extrinsic -career and grade- motivation) on learning human histology in health science curricula and their relationship with the final performance of the students in histology. METHODS: Glynn Science Motivation Questionnaire II was used to compare students' motivation components to learn histology in 367 first-year male and female undergraduate students enrolled in medical, dentistry and pharmacy degree programs. RESULTS: For intrinsic motivation, career motivation and self-efficacy, the highest values corresponded to medical students, whereas dentistry students showed the highest values for self-determination and grade motivation. Genders differences were found for career motivation in medicine, self-efficacy in dentistry, and intrinsic motivation, self-determination and grade motivation in pharmacy. Career motivation and self-efficacy components correlated with final performance in histology of the students corresponding to the three curricula. CONCLUSIONS: Our results show that the overall motivational profile for learning histology differs among medical, dentistry and pharmacy students. This finding is potentially useful to foster their learning process, because if they are metacognitively aware of their motivation they will be better equipped to self-regulate their science-learning behavior in histology. This information could be useful for instructors and education policy makers to enhance curricula not only on the cognitive component of learning but also to integrate students' levels and types of motivation into the processes of planning, delivery and evaluation of medical education.
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Histologia/educação , Motivação , Estudantes/psicologia , Educação em Odontologia , Educação Médica , Educação em Farmácia , Feminino , Humanos , Masculino , Escolas para Profissionais de Saúde , Fatores Sexuais , EspanhaRESUMO
BACKGROUND AIMS: One of the most important issues in tissue engineering (TE) is the search for a suitable stem cell reservoir with optimal cell viability levels for the development of new tissues relevant for therapeutic needs. The aim of this study was to evaluate the cell viability levels of 10 sequential cell passages of human dental pulp stem cells (hDPSC) to determine their potential for TE techniques. METHODS: To assess the average cell viability levels of hDPSC, four cell viability assays were used in a combinatorial approach: trypan blue exclusion test, water-soluble tetrazolium 1 assay, live/dead assay and electron probe x-ray microanalysis. RESULTS: The results showed that cell viability as determined by trypan blue staining and live/dead assays was greater than 85%, with a significant decrease at the second passage (P < 0.05) and a significant increase at the ninth passage (P < 0.05). Electron probe x-ray microanalysis showed that the highest cell viability corresponded to the ninth passage, with the lowest K/Na values found at the third passage. No statistical differences were found among the different passages for the water-soluble tetrazolium 1 assay (P = 0.219). CONCLUSIONS: Assessment of average cell viability levels showed that the highest viability of hDPSC was reached after nine passages, suggesting that this passage would be the most adequate for use in TE protocols.
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Polpa Dentária/citologia , Células-Tronco/citologia , Engenharia Tecidual , Técnicas de Cultura de Células , Diferenciação Celular , Sobrevivência Celular , Células Cultivadas , Microanálise por Sonda Eletrônica , Citometria de Fluxo , Humanos , Sais de Tetrazólio , Azul TripanoRESUMO
A previously developed fibrin-agarose skin model-UGRSKIN-showed promising clinical results in severely burnt patients. To determine the histological parameters associated to the biocompatibility and therapeutic effects of this model, we carried out a comprehensive structural and ultrastructural study of UGRSKIN grafted in severely burnt patients after 3 months of follow-up. The grafted epidermis was analogue to native human skin from day 30th onward, revealing well-structured strata with well-differentiated keratinocytes expressing CK5, CK8, CK10, claudin, plakoglobin, filaggrin, and involucrin in a similar way to controls, suggesting that the epidermis was able to mature and differentiate very early. Melanocytes and Langerhans cells were found from day 30th onward, together with a basement membrane, abundant hemidesmosomes and lack of rete ridges. At the dermal layer, we found an interface between the grafted skin and the host tissue at day 30th, which tended to disappear with time. The grafted superficial dermis showed a progressive increase in properly-oriented collagen fibers, elastic fibers and proteoglycans, including decorin, similarly to control dermis at day 60-90th of in vivo follow-up. Blood vessels determined by CD31 and SMA expression were more abundant in grafted skin than controls, whereas lymphatic vessels were more abundant at day 90th. These results contribute to shed light on the histological parameters associated to biocompatibility and therapeutic effect of the UGRSKIN model grafted in patients and demonstrate that the bioengineered skin grafted in patients is able to mature and differentiate very early at the epithelial level and after 60-90 days at the dermal level.
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Purpose: We carried out a histological characterization analysis of the stromal layer of human heterotypic cornea substitutes generated with extra-corneal cells to determine their putative usefulness in tissue engineering. Methods: Human bioartificial corneas were generated using nanostructured fibrin-agarose biomaterials with corneal stromal cells immersed within. To generate heterotypical corneas, umbilical cord Wharton's jelly stem cells (HWJSC) were cultured on the surface of the stromal substitutes to obtain an epithelial-like layer. These bioartificial corneas were compared with control native human corneas and with orthotypical corneas generated with human corneal epithelial cells on top of the stromal substitute. Both the corneal stroma and the basement membrane were analyzed using histological, histochemical and immunohistochemical methods in samples kept in culture and grafted in vivo for 12 months in the rabbit cornea. Results: Our results showed that the stroma of the bioartificial corneas kept ex vivo showed very low levels of fibrillar and non-fibrillar components of the tissue extracellular matrix. However, in vivo implantation resulted in a significant increase of the contents of collagen, proteoglycans, decorin, keratocan and lumican in the corneal stroma, showing higher levels of maturation and spatial organization of these components. Heterotypical corneas grafted in vivo for 12 months showed significantly higher contents of collagen fibers, proteoglycans and keratocan. When the basement membrane was analyzed, we found that all corneas grafted in vivo showed intense PAS signal and higher contents of nidogen-1, although the levels found in human native corneas was not reached, and a rudimentary basement membrane was observed using transmission electron microscopy. At the epithelial level, HWJSC used to generate an epithelial-like layer in ex vivo corneas were mostly negative for p63, whereas orthotypical corneas and heterotypical corneas grafted in vivo were positive. Conclusion: These results support the possibility of generating bioengineered artificial corneas using non-corneal HWJSC. Although heterotypical corneas were not completely biomimetic to the native human corneas, especially ex vivo, in vivo grafted corneas demonstrated to be highly biocompatible, and the animal cornea became properly differentiated at the stroma and basement membrane compartments. These findings open the door to the future clinical use of these bioartificial corneas.
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BACKGROUND: Histology of human oral mucosa is closely related with its function and anatomical location, and a proper characterization of the human masticatory oral mucosa could be very useful in periodontal pathology. OBJECTIVE: In the present work, we have carried out a comprehensive study in order to determine the main histological features of parakeratinized (POM) and orthokeratinized (OOM) masticatory human oral mucosa using light and electron microscopy. METHODS: To perform this, we have used several histological, histochemical and immunohistochemical methods to detect key markets at the epithelial, basement membrane and connective tissue levels. RESULTS: Our results demonstrated that POM and OOM share many histological similarities, as expected. However, important differences were observed at the epithelial layer of POM, that was significantly thicker than the epithelial layer found in OOM, especially due to a higher number of cells at the stratum spinosum. The expression pattern of CK10 and filaggrin revealed intense signal expression in OOM as compared to POM. Collagen and proteoglycans were more abundant in OOM stroma than in POM. No differences were found for blood vessels and basement membrane. CONCLUSION: These results may contribute to a better understanding of the pathological conditions affecting the human masticatory oral mucosa. In addition, these findings could be useful for the generation of different types of oral mucosa by tissue engineering techniques. RESEARCH HIGHLIGHTS: Microscopical features of parakeratinized and orthokeratinized masticatory human oral mucosa showed important differences at both, epithelial and stromal levels. Parakeratinized masticatory human oral mucosa exert thicker epithelial layer, especially, at the stratum spinosum in comparison to orthokeratinized human oral mucosa. Cytokeratin 10 and filaggrin human epithelial markers were intensively expressed in orthokeratinized masticatory human oral mucosa in comparison to parakeratinized masticatory human oral mucosa. At the stromal level, orthokeratinized masticatory human oral mucosa exhibit higher levels of collagen and proteoglycans than parakeratinized masticatory oral mucosa. The deep knowledge of histological features of masticatory oral mucosa could lead to a better understanding of oral mucosa pathology and advanced treatments.
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Proteínas Filagrinas , Mucosa Bucal , Humanos , Mucosa Bucal/patologia , Microscopia Eletrônica , Colágeno , ProteoglicanasRESUMO
Genomic analysis and digitalization of medical records have led to a big data scenario within hematopathology. Artificial intelligence and machine learning tools are increasingly used to integrate clinical, histopathological, and genomic data in lymphoid neoplasms. In this study, we identified global trends, cognitive, and social framework of this field from 1990 to 2020. Metadata were obtained from the Clarivate Analytics Web of Science database in January 2021. A total of 525 documents were assessed by document type, research areas, source titles, organizations, and countries. SciMAT and VOSviewer package were used to perform scientific mapping analysis. Geographical distribution showed the USA and People's Republic of China as the most productive countries, reporting up to 190 (36.19%) of all documents. A third-degree polynomic equation predicts that future global production in this area will be three-fold the current number, near 2031. Thematically, current research is focused on the integration of digital image analysis and genomic sequencing in Non-Hodgkin lymphomas, prediction of chemotherapy response and validation of new prognostic models. These findings can serve pathology departments to depict future clinical and research avenues, but also, public institutions and administrations to promote synergies and optimize funding allocation.
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Big Data , Bases de Dados Factuais , Diagnóstico por Computador , Linfoma não Hodgkin/diagnóstico , Aprendizado de Máquina , Modelos Biológicos , China/epidemiologia , Feminino , Humanos , Linfoma não Hodgkin/epidemiologia , Masculino , Estados Unidos/epidemiologiaRESUMO
Critical defects of the mandibular bone are very difficult to manage with currently available materials and technology. In the present work, we generated acellular and cellular substitutes for human bone by tissue engineering using nanostructured fibrin-agarose biomaterials, with and without adipose-tissue-derived mesenchymal stem cells differentiated to the osteogenic lineage using inductive media. Then, these substitutes were evaluated in an immunodeficient animal model of severely critical mandibular bone damage in order to assess the potential of the bioartificial tissues to enable bone regeneration. The results showed that the use of a cellular bone substitute was associated with a morpho-functional improvement of maxillofacial structures as compared to negative controls. Analysis of the defect site showed that none of the study groups fully succeeded in generating dense bone tissue at the regeneration area. However, the use of a cellular substitute was able to improve the density of the regenerated tissue (as determined via CT radiodensity) and form isolated islands of bone and cartilage. Histologically, the regenerated bone islands were comparable to control bone for alizarin red and versican staining, and superior to control bone for toluidine blue and osteocalcin in animals grafted with the cellular substitute. Although these results are preliminary, cellular fibrin-agarose bone substitutes show preliminary signs of usefulness in this animal model of severely critical mandibular bone defect.
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PURPOSE: Human cornea substitutes generated by tissue engineering currently require limbal stem cells for the generation of orthotypical epithelial cell cultures. We recently reported that bioengineered corneas can be fabricated in vitro from a heterotypical source obtained from Wharton's jelly in the human umbilical cord (HWJSC). METHODS: Here, we generated a partial thickness cornea model based on plastic compression nanostructured fibrin-agarose biomaterials with cornea epithelial cells on top, as an orthotypical model (HOC), or with HWJSC, as a heterotypical model (HHC), and determined their potential in vivo usefulness by implantation in an animal model. RESULTS: No major side effects were seen 3 and 12 months after implantation of either bioengineered partial cornea model in rabbit corneas. Clinical results determined by slit lamp and optical coherence tomography were positive after 12 months. Histological and immunohistochemical findings demonstrated that in vitro HOC and HHC had moderate levels of stromal and epithelial cell marker expression, whereas in vivo grafted corneas were more similar to control corneas. CONCLUSION: These results suggest that both models are potentially useful to treat diseases requiring anterior cornea replacement, and that HHC may be an efficient alternative to the use of HOC which circumvents the need to generate cornea epithelial cell cultures.
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Number of publications has been widely used as a measure of research output, especially academic and university research. Number of publications in tissue engineering (TE) has increased year by year since early 1990s. However, after an exponential growth phase, recently publications increase at lower rates, suggesting a consolidation process in which reviews become a relevant and high-evidence document type. The aim of this study is to perform a scientometric evaluation of published literature reviews on TE to assess the status of scientific evolution and confirm the consolidation of TE as a research area. Published reviews on TE from 1991 to 2018 were retrieved from Web of Science core collection and this corpus of knowledge was analyzed by growth rate, research area, source title, and citation. Our results revealed that TE can be considered a consolidating area as it leaves the forefront stage of a gompertzian growth curve model. Original research/review ratio is lineally decreasing during the past decade. The emergence of reviews serves to confirm and refute hypothesis and build up a more reliable theoretical framework as well as a guide for future educational approaches. Distribution assessment of categories and journals indicates the multidisciplinary profile of this area focused on the design and development of new tissues. Biomedical sciences become relevant productors of reviews as they need to support TE innovations with high evidence leading to a safer and more efficient treatment of current injuries and diseases. Impact statement Scientometric analysis of published reviews about tissue engineering (TE) suggests that TE can be considered a consolidating area as it leaves the forefront stage of a gompertzian growth curve model. Biomedical sciences become relevant productors of reviews as they need to support TE innovations with high evidence leading to a safer and more efficient treatment of current injuries and diseases.
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Pesquisa Biomédica/métodos , Engenharia Tecidual , Animais , Humanos , Publicações , Revisões Sistemáticas como AssuntoRESUMO
Recent advances in tissue engineering offer innovative clinical alternatives in dentistry and regenerative medicine. Tissue engineering combines human cells with compatible biomaterials to induce tissue regeneration. Shortening the fabrication time of biomaterials used in tissue engineering will contribute to treatment improvement, and biomaterial functionalization can be exploited to enhance scaffold properties. In this work, we have tested an alternative biofabrication method by directly including human oral mucosa tissue explants within the biomaterial for the generation of human bioengineered mouth and dental tissues for use in tissue engineering. To achieve this, acellular fibrin-agarose scaffolds (AFAS), non-functionalized fibrin-agarose oral mucosa stroma substitutes (n-FAOM), and novel functionalized fibrin-agarose oral mucosa stroma substitutes (F-FAOM) were developed and analyzed after 1, 2, and 3 weeks of in vitro development to determine extracellular matrix components as compared to native oral mucosa controls by using histochemistry and immunohistochemistry. Results demonstrate that functionalization speeds up the biofabrication method and contributes to improve the biomimetic characteristics of the scaffold in terms of extracellular matrix components and reduce the time required for in vitro tissue development.
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IMPACT STATEMENT: This study evaluates the cognitive structure and social behavior of tissue engineering (TE) based on a science mapping analysis. Understanding the terms and topics that play a key role in the development of TE can help administrative authorities to better plan funding. Moreover, a better knowledge of collaborative networks in TE and the identification of potential new opportunities for collaboration may enhance synergies in scientific activities to implement future approaches to therapy.
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Pesquisa Biomédica , Comportamento Cooperativo , Disseminação de Informação , Meio Social , Engenharia Tecidual , Humanos , Apoio à Pesquisa como AssuntoRESUMO
We evaluated the efficiency of several protocols to preserve the main components of decellularized tissue scaffolds for delayed use. Decellularized rat intestine scaffolds were generated by using SDS and triton X-100 and preserved for 3 months subjected to eight freeze-drying (F1 to F8) and 14 cryopreservation protocols (C1 to C14). Morphological analysis showed that cryopreservation tended to preserve the tissue morphostructure more efficiently than freeze-drying. Histological analysis showed that the content of proteoglycans and glycoproteins was efficiently preserved by most methods. The protocols that most efficiently preserved collagen fibers were those using trehalose and saccharose for freeze-drying (F2, F3, and F7 protocols) and DMSO, albumin, and saccharose (C3, C5, C6, C12) for cryopreservation. Most freeze-drying protocols and cryopreservation protocols with DMSO, albumin, and maltose (C6, C7, C13, and C14) efficiently preserved reticular fibers. For the elastic fibers, freeze-drying methods with trehalose and maltose (F2, F4, F6, and F8) properly preserved these fibers, with the results of most cryopreservation methods comparable to controls. These results suggest that freeze-drying using 0.1M trehalose and cryopreservation in the presence of 8% DMSO and 4.6% albumin are more efficient than other protocols in preserving the scaffold morphostructure and histological composition. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 488-500, 2018.
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Criopreservação , Intestino Delgado/efeitos dos fármacos , Engenharia Tecidual , Albuminas/química , Albuminas/farmacologia , Animais , Dimetil Sulfóxido/química , Dimetil Sulfóxido/farmacologia , Liofilização , Humanos , Intestino Delgado/química , Masculino , Maltose/química , Maltose/farmacologia , Octoxinol/química , Octoxinol/farmacologia , Ratos , Ratos Wistar , Dodecilsulfato de Sódio/química , Dodecilsulfato de Sódio/farmacologia , Sacarose/química , Sacarose/farmacologia , Trealose/química , Trealose/farmacologiaRESUMO
Tissue engineering (TE) is defined as a multidisciplinary scientific discipline with the main objective to develop artificial bioengineered living tissues to regenerate damaged or lost tissues. Since its appearance in 1988, TE has globally spread to improve current therapeutic approaches, entailing a revolution in clinical practice. The aim of this study is to analyze global research trends on TE publications to realize the scenario of TE research from 1991 to 2016 by using document retrieval from Web of Science database and bibliometric analysis. Document type, language, source title, authorship, countries and filiation centers, and citation count were evaluated in 31,859 documents. Obtained results suggest a great multidisciplinary role of TE due to a wide spectrum-up to 51-of scientific research areas identified in the corpus of literature, being predominant technological disciplines as Material Sciences or Engineering, followed by biological and biomedical areas, as Cell Biology, Biotechnology, or Biochemistry. Distribution of authorship, journals, and countries revealed a clear imbalance, in which a minority is responsible for a majority of documents. Such imbalance is notorious in authorship, where a 0.3% of authors are involved in half of the whole production.
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Engenharia Tecidual/tendências , Autoria , Pesquisa Biomédica , Publicações Periódicas como Assunto , PublicaçõesRESUMO
Introducción y objetivo: Los avances en el campo de la Ingeniería Tisular han promovido el desarrollo de sustitutos de piel y su aplicación en el campo de la Cirugía Plástica. Uno de los principales inconvenientes de la bioingeniería de la piel es la necesidad de obtener una gran cantidad de células viables en periodos cortos de tiempo, lo que conlleva que el proceso de biofabricación sea largo y complejo. En este estudio se pretende valorar los efectos de la aplicación de tres tipos diferentes de secretoma derivados de células madre mesenquimales humanas en cultivos de fibroblastos con el objetivo de favorecer la escalabilidad de los procesos de fabricación de piel artificial. Material y método: Se evaluaron los efectos a las 24, 48 y 72 horas sobre la viabilidad, la proliferación y la migración celular de fibroblastos humanos tras la aplicación de dos concentraciones (C1 y C2) de tres tipos diferentes de secretoma derivado de células madre mesenquimales humanas. Los resultados in vitro fueron contrastados en un modelo in vivo. Resultados: El uso de secretoma derivado de células madre mesenquimales mejoró los protocolos de cultivo de fibroblastos actualmente disponibles. El uso de secretoma se asoció a un aumento de la proliferación y migración celular manteniendo cifras altas de viabilidad. Los datos fueron especialmente positivos para el secretoma de células madre mesenquimales de pulpa dental y de tejido adiposo. Conclusiones: El efecto de la aplicación de secretoma procedentes de células madre mesenquimales permite mantener cifras de viabilidad celular elevadas, además de incrementar el ritmo de proliferación de fibroblastos. Los estudios in vivo e in vitro no evidenciaron efectos adversos a corto plazo. (AU)
Background and objective: Advances in Tissue Engineering promoted the development of skin substitutes. One of the main drawbacks of skin bioengineering is the requirement of a considerable quantity of viable cells in short periods of time, which leads to a challenging biofabrication process. This article aims to analyse the effects of the application of three different types of human mesenchymal stem cell-derived secretome in fibroblast cultures. The final goal is to achieve new strategies to promote the scalability of artificial skin manufacturing processes. Methods: The effects of the three different types of human mesenchymal stem cell-derived secretome were analyzed at 24, 48 and 72 hours. To study cell viability, cell proliferation and cell migration we exposed human fibroblasts to different secretome concentrations (C1 and C2). An in vivo study was proposed to corroborate in vitro results. Results: The use of mesenchymal stem cell-derived secretome improved the currently available fibroblast culture protocols. The use of secretome was associated with increased cell proliferation and cell migration while maintaining high viability values. Data were especially positive when secretome from dental pulp mesenchymal stem cells and adipose tissue mesenchymal stem cells were applied. Conclusions: The application of mesenchymal stem cell-derived secretome maintained high cell viability data and increased fibroblast proliferation. In vivo and in vitro studies showed no short-term adverse effects. (AU)