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1.
Rev Sci Tech ; 38(1): 303-314, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31564720

RESUMEN

Under the International Health Regulations (IHR, 2005), a legally binding document adopted by 196 States Parties, countries are required to develop their capacity to rapidly detect, assess, notify and respond to unusual health events of potential international concern. To support countries in monitoring and enhancing their capacities and complying with the IHR (2005), the World Health Organization (WHO) developed the IHR Monitoring and Evaluation Framework (IHR MEF). This framework comprises four complementary components: the State Party Annual Report, the Joint External Evaluation, after-action reviews and simulation exercises. The first two are used to review capacities and the second two to help to explore their functionality. The contribution of different disciplines, sectors, and areas of work, joining forces through a One Health approach, is essential for the implementation of the IHR (2005). Therefore, WHO, in partnership with the Food and Agriculture Organization of the United Nations (FAO), the World Organisation for Animal Health (OIE), and other international and national partners, has actively worked on facilitating the inclusion of the relevant sectors, in particular the animal health sector, in each of the four components of the IHR MEF. Other tools complement the IHR MEF, such as the WHO/OIE IHR-PVS [Performance of Veterinary Services] National Bridging Workshops, which facilitate the optimal use of the results of the IHR MEF and the OIE Performance of Veterinary Services Pathway and create an opportunity for stakeholders from animal health and human health services to work on the coordination of their efforts. The results of these various tools are used in countries' planning processes and are incorporated in their National Action Plan for Health Security to accelerate the implementation of IHR core capacities. The present article describes how One Health is incorporated in all components of the IHR MEF.


En vertu du Règlement sanitaire international (RSI, 2005), instrument juridique ayant force obligatoire pour les 196 États Parties dans le monde, les pays s'engagent à renforcer leurs capacités de détection, d'évaluation, de notification et de réaction en cas d'événements sanitaires inhabituels ou présentant une dimension internationale inquiétante. Le Cadre de suivi et d'évaluation du RSI (2005) a été élaboré par l'Organisation mondiale de la santé (OMS) afin de soutenir les pays souhaitant évaluer et améliorer leurs capacités et leur niveau de conformité avec le RSI (2005). Ce cadre comprend quatre composantes complémentaires : le rapport annuel de l'État Partie, l'Évaluation extérieure conjointe, les examens « après action¼ et les exercices de simulation. Les deux premières composantes permettent de faire le point sur les capacités tandis que les deux dernières visent une connaissance détaillée de leur fonctionnement. La mise en oeuvre du RSI (2005) demande aux différentes disciplines, secteurs et domaines d'activités de fédérer leurs forces dans une approche Une seule santé. Par conséquent, en partenariat avec l'Organisation des Nations Unies pour l'alimentation et l'agriculture (FAO), avec l'Organisation mondiale de la santé animale (OIE) et avec d'autres partenaires internationaux et nationaux, l'OMS a fait en sorte de faciliter l'intégration de tous les secteurs concernés, en particulier celui de la santé animale, dans les diverses composantes du Cadre d'évaluation du RSI. D'autres outils complètent celui-ci, en particulier les ateliers de liaison nationaux OMS/OIE sur le RSI et le Processus d'évaluation des performances des Services vétérinaires (PVS), dont le but est de faciliter l'utilisation optimale des résultats du Cadre d'évaluation du RSI et du Processus PVS de l'OIE et de fournir aux acteurs des services de santé animale et de santé publique la possibilité de se concerter sur les modalités d'une synergie de leur action. Les résultats de ces outils sont ensuite pris en compte par les pays lors des procédures de planification et intégrés dans les Plans d'action nationaux pour la sécurité sanitaire afin d'accélérer la mise en oeuvre des capacités fondamentales décrites dans le RSI. Les auteurs décrivent l'intégration du concept Une seule santé dans chacune des composantes du Cadre d'évaluation du RSI.


Según lo dispuesto en el Reglamento Sanitario Internacional (RSI, 2005), documento jurídicamente vinculante suscrito por 196 Estados Partes, los países están obligados a dotarse de la capacidad necesaria para detectar, evaluar, notificar y afrontar con rapidez todo evento sanitario inusual que pueda revestir importancia internacional. Para ayudar a los países a dotarse de mejores capacidades, a seguir de cerca su evolución al respecto y a dar cumplimiento al RSI (2005), la Organización Mundial de la Salud (OMS) elaboró el marco de seguimiento y evaluación del RSI, que consta de cuatro elementos complementarios: el informe anual que debe presentar cada Estado Parte; la evaluación externa conjunta; exámenes posteriores a las intervenciones; y ejercicios de simulación. Los dos primeros sirven para examinar las capacidades, y los dos segundos para ayudar a estudiar su funcionalidad. Para la aplicación del RSI (2005) es fundamental la contribución de diferentes disciplinas, sectores y ámbitos de trabajo, que aúnen esfuerzos actuando desde los postulados de Una sola salud. Por ello la OMS, en colaboración con la Organización de las Naciones Unidas para la Alimentación y la Agricultura (FAO), la Organización Mundial de Sanidad Animal (OIE) y otros asociados internacionales y nacionales, ha trabajado activamente para facilitar la integración de los sectores pertinentes, en particular el de la sanidad animal, en cada uno de los cuatro componentes del marco de seguimiento y evaluación del RSI. Hay otros dispositivos que vienen a complementar este marco, por ejemplo los talleres nacionales dedicados a la creación de nexos entre el RSI y el proceso PVS (Prestaciones de los Servicios Veterinarios) de la OIE, organizados conjuntamente por la OMS y la OIE, que facilitan un uso idóneo de los resultados del marco de seguimiento y evaluación del RSI y del proceso PVS y brindan a las partes interesadas de los servicios sanitarios y zoosanitarios la oportunidad de trabajar sobre la coordinación de sus respectivas actividades. Los resultados de estas diversas herramientas alimentan después los procesos de planificación de los países y son incorporados a su Plan de acción nacional de seguridad sanitaria para acelerar la implantación de las capacidades básicas prescritas en el RSI. Los autores explican cómo se incorpora la filosofía de Una sola salud a todos los componentes del marco de seguimiento y evaluación del RSI.


Asunto(s)
Reglamento Sanitario Internacional , Salud Única , Animales , Brotes de Enfermedades/prevención & control , Salud Global , Humanos , Cooperación Internacional , Salud Única/normas , Organización Mundial de la Salud
2.
Biomed Mater Eng ; 28(s1): S47-S56, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28372277

RESUMEN

Thanks to their immune properties, the mesenchymal stem cells (MSC) are a promising source for cell therapy. Current clinical trials show that MSC administrated to patients can treat different diseases (graft-versus-host disease (GVHD), liver cirrhosis, systemic lupus, erythematosus, rheumatoid arthritis, type I diabetes…). In this case, the most common mode of cell administration is the intravenous injection, and the hemodynamic environment of cells induced by blood circulation could interfere on their behavior during the migration and homing towards the injured site. After a brief review of the mechanobiology concept, this paper will help in understanding how the mechanical environment could interact with MSC behavior once they are injected to patient in cell-based treatment.


Asunto(s)
Hemodinámica , Células Madre Mesenquimatosas/citología , Animales , Fenómenos Biomecánicos , Biofisica , Movimiento Celular , Quimiotaxis , Humanos , Inyecciones Intravenosas , Trasplante de Células Madre Mesenquimatosas/métodos , Migración Transendotelial y Transepitelial
3.
Biomed Mater Eng ; 28(s1): S57-S63, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28372278

RESUMEN

With their proliferation, differentiation into specific cell types, and secretion properties, mesenchymal stromal/stem cells (MSC) are very interesting tools to be used in regenerative medicine. Bone marrow (BM) was the first MSC source characterized. In the frame of autologous MSC therapy, it is important to detect donor's parameters affecting MSC potency. Age of the donors appears as one parameter that could greatly affect MSC properties. Moreover, in vitro cell expansion is needed to obtain the number of cells necessary for clinical developments. It will lead to in vitro cell aging that could modify cell properties. This review recapitulates several studies evaluating the effect of in vitro and in vivo MSC aging on cell properties.


Asunto(s)
Senescencia Celular , Células Madre Mesenquimatosas/citología , Envejecimiento , Animales , Diferenciación Celular , Proliferación Celular , Humanos , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Estrés Oxidativo , Medicina Regenerativa , Homeostasis del Telómero
4.
Biomed Mater Eng ; 28(s1): S121-S127, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28372287

RESUMEN

The relevance of research on reconstructed organs is justified by the lack of organs available for transplant and the growing needs for the ageing population. The development of a reconstructed organ involves two parallel complementary steps: de-cellularization of the organ with the need to maintain the structural integrity of the extracellular matrix and vascular network and re-cellularization of the scaffold with stem cells or resident cells.Whole organ engineering for liver, heart, lung or kidneys, is particularly difficult because of the structural complexity of organs and heterogeneity of cells. Rodent, porcine and rhesus monkey organs have been de-cellularized to obtain a scaffold with preserved extracellular matrix and vascular network. As concern the cells for re-cellularization, embryonic, foetal, adult, progenitor stem cells and also iPS have been proposed.Heart construction could be an alternative option for the treatment of cardiac insufficiency. It is based on the use of an extra-cellular matrix coming from an animal's heart and seeded with cells likely to reconstruct a normal cardiac function. Though de-cellularization techniques now seem controlled, the issues posed by the selection of cells capable of generating the various components of cardiac tissue are not settled yet. In addition, the recolonisation of the matrix does not only depend on the phenotype of cells that are used, but it is also impacted by the nature of biochemical signals emitted.Recent researches have shown that it is possible to use decellularized whole liver treated by detergents as scaffold, which keeps the entire network of blood vessels and the integrated extracellular matrix (ECM). Beside of decellularized whole organ scaffold seeding cells selected to repopulate a decellularized liver scaffold are critical for the function of the bioengineered liver. At present, potential cell sources are hepatocyte, and mesenchymal stem cells.Pulmonary regeneration using engineering approaches is complex. In fact, several types of local progenitor cells that contribute to cell repair have been described at different levels of the respiratory tract. Moving towards the alveoles, one finds bronchioalveolar stem cells as well as epithelial cells and pneumocytes. A promising option to increase the donor organ pool is to use allogeneic or xenogeneic decellularized lungs as a scaffold to engineer functional lung tissue ex vivo.The kidney is certainly one of the most difficult organs to reconstruct due to its complex nature and the heterogeneous nature of the cells. There is relatively little research on auto-construction, and experiments have been performed on rats, pigs and monkeys.Nevertheless, before these therapeutic approaches can be applied in clinical practice, many researches are necessary to understand and in particular the behaviour of cells on the decellularized organs as well as the mechanisms of their interaction with the microenvironment. Current knowledges allow optimism for the future but definitive answers can only be given after long term animal studies and controlled clinical studies.


Asunto(s)
Riñón/citología , Hígado/citología , Pulmón/citología , Miocardio/citología , Células Madre/citología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Matriz Extracelular/química , Corazón/crecimiento & desarrollo , Humanos , Riñón/crecimiento & desarrollo , Hígado/crecimiento & desarrollo , Pulmón/crecimiento & desarrollo
5.
Clin Hemorheol Microcirc ; 64(4): 613-633, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27791997

RESUMEN

Most human tissues do not regenerate spontaneously, which is why "cell therapy" are promising alternative treatments. The Principe is simple: patients' or donors' cells are collected and introduced into the injured tissues or organs directly or in a porous 3D material, with or without modification of their properties. This concept of regenerative medicine is an emerging field which can be defined as "the way to improve health and quality of life by restoring, maintaining, or enhancing tissue and organ functions".There is an extraordinarily wide range of opportunities for clinical applications: artheropathies, diabetes, cartilage defects, bone repair, burns, livers or bladder regeneration, organs reconstruction (lung, heart, liver ...) neurodegenerative disorders, sepsis ...  Different stem cells (SC) with different potential can be used and characterised (totipotent, mesenchymal of different origins, especially those present in tissues...). Today it is undeniable that cells like bone marrow, adipose tissue or Wharton Jelly stem cells, are of potential interest for clinical applications because they are easily separated and prepared and no ethical problems are involved in their use.In this paper some potential clinical applications in the vascular field are considered: peripheral arteriopathy in diabetic patients, cardiac insufficiency, traitment of erectile dysfunction, or organ regeneration with liver as example. But the regeneration of tissue or organ is and will remain a challenge for the future development of cell therapy. Many problems remain to be solved that could lead to the development of innovative strategies to facilitate cell differentiation, increase the yield of cells and ensure a standardised product, overcome the risks of teratogenic effects and/or immune reactions, enable grafting via direct cell or biotissue transplantation and avoid legal issues involved in national regulations.


Asunto(s)
Medicina Regenerativa , Células Madre/metabolismo , Humanos , Calidad de Vida , Células Madre/citología , Ingeniería de Tejidos
6.
Stem Cells Int ; 2015: 734731, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26300923

RESUMEN

Since the 1960s and the therapeutic use of hematopoietic stem cells of bone marrow origin, there has been an increasing interest in the study of undifferentiated progenitors that have the ability to proliferate and differentiate into various tissues. Stem cells (SC) with different potency can be isolated and characterised. Despite the promise of embryonic stem cells, in many cases, adult or even fetal stem cells provide a more interesting approach for clinical applications. It is undeniable that mesenchymal stem cells (MSC) from bone marrow, adipose tissue, or Wharton's Jelly are of potential interest for clinical applications in regenerative medicine because they are easily available without ethical problems for their uses. During the last 10 years, these multipotent cells have generated considerable interest and have particularly been shown to escape to allogeneic immune response and be capable of immunomodulatory activity. These properties may be of a great interest for regenerative medicine. Different clinical applications are under study (cardiac insufficiency, atherosclerosis, stroke, bone and cartilage deterioration, diabetes, urology, liver, ophthalmology, and organ's reconstruction). This review focuses mainly on tissue and organ regeneration using SC and in particular MSC.

7.
Cell Prolif ; 48(2): 157-65, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25656979

RESUMEN

End-stage liver disease can be the termination of acute or chronic liver diseases, with manifestations of liver failure; transplantation is currently an effective treatment for these. However, transplantation is severely limited due to the serious lack of donors, expense, graft rejection and requirement of long-term immunosuppression. Mesenchymal stem cells (MSCs) have attracted considerable attention as therapeutic tools as they can be obtained with relative ease and expanded in culture, along with features of self-renewal and multidirectional differentiation. Many scientific groups have sought to use MSCs differentiating into functional hepatocytes to be used in cell transplantation with liver tissue engineering to repair diseased organs. In most of the literature, hepatocyte differentiation refers to use of various additional growth factors and cytokines, such as hepatocyte growth factor (HGF), fibroblast growth factor (FGF), epidermal growth factor (EGF), oncostatin M (OSM) and more, and most are involved in signalling pathway regulation and cell-cell/cell-matrix interactions. Signalling pathways have been shown to play critical roles in embryonic development, tumourigenesis, tumour progression, apoptosis and cell-fate determination. However, mechanisms of MSCs differentiating into hepatocytes, particularly signalling pathways involved, have not as yet been completely illustrated. In this review, we have focused on progress of signalling pathways associated with mesenchymal stem cells differentiating into hepatocytes along with the stepwise differentiation procedure.


Asunto(s)
Diferenciación Celular/fisiología , Tratamiento Basado en Trasplante de Células y Tejidos , Hepatocitos/citología , Células Madre Mesenquimatosas/citología , Proliferación Celular , Enfermedad Hepática en Estado Terminal/terapia , Humanos , Hígado/metabolismo , Trasplante de Células Madre Mesenquimatosas , Transducción de Señal , Ingeniería de Tejidos
8.
Biomed Mater Eng ; 25(1 Suppl): 3-26, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25538052

RESUMEN

Since the 1960s and the therapeutic use of hematopoietic stem cells of bone marrow origin, there has been increasing interest in the study of undifferentiated progenitors that have ability to proliferate and differentiate in different tissues. Different stem cells (SC) with different potential can be isolated and characterised. Despite the promise of embryonic stem cells, in many cases, adult stem cells provide a more interesting approach to clinical applications. It is undeniable that mesenchymal stem cells (MSC) from bone marrow, adipose tissue or MSC of Wharton Jelly, which have limited potential, are of interest for clinical applications in regenerative medicine because they are easily separated and prepared and no ethical problems are involved in their use.During the last 10 years, these multipotent cells have generated considerable interest and in particular have been shown to escape allogeneic immune response and be capable of immunomodulatory activity. These properties may be of a great interest for regenerative medicine. Different clinical applications are under study (cardiac insufficiency, atherosclerosis, stroke, bone, cartilage, diabetes, ophthalmology, urology, liver, organ's reconstruction…).


Asunto(s)
Regeneración/fisiología , Investigación con Células Madre , Trasplante de Células Madre/métodos , Células Madre/citología , Células Madre/fisiología , Ingeniería de Tejidos/métodos , Animales , Humanos
9.
Clin Hemorheol Microcirc ; 56(3): 231-46, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23603323

RESUMEN

Nitric oxide is implicated in the target action of Nebivolol, a selective ß1 adrenoceptor blocker used in hypertension treatment. As the Nitric Oxide (NO) production and the actin cytoskeleton are linked, the aim of this work was to study the involvement of actin cytoskeleton on mechanism of action of Nebivolol in cultured endothelial cells. We studied the effect of Nebivolol (200 µM) on actin filaments remodeling and its impact on NO production and eNOS activation. Results showed that Nebivolol perturbs actin filaments polymerization, increases NO production and eNOS activity between 30 minutes and 1 h. Stabilization of actin filaments with phalloïdine (50 µM) abolishes Nebivolol effects on eNOS activation and NO production. Furthermore, Rho-kinase activity decreased during the first hour of Nebivolol treatment, then increased after 3 h, while actin filaments repolymerized, eNOS activation and NO production decreased. In SMCs, Nebivolol induced a decrease in the Rho-kinase activity from 1 h until 24 h of incubation. In conclusion, we suggest that Nebivolol induced NO production in Endothelial Cells (ECs) via complementary actions between actin cytoskeleton remodeling inducing eNOS activation and Rho-kinase implication. The effect of Nebivolol on ECs occurs during the first hour, this effect on SMCs seems to be maintained until 24 h, explaining persisted action of Nebivolol observed in vivo.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Benzopiranos/metabolismo , Etanolaminas/metabolismo , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico Sintasa de Tipo III/metabolismo , Quinasas Asociadas a rho/metabolismo , Células Endoteliales , Humanos , Nebivolol , Óxido Nítrico/farmacología , Polimerizacion
10.
Biomed Mater Eng ; 23(4): 311-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23798652

RESUMEN

Collagen gels could be used as carriers in tissue engineering to improve cell retention and distribution in the defect. In other respect hydroxyapatite could be added to gels to improve mechanical properties and regulate gel contraction. The aim of this work was to analyze the feasibility to incorporate hydroxyapatite into collagen gels and culture mesenchymal stem cells inside it. Human bone marrow mesenchymal stem cells (hMSC-BM) were used in this study. Gels were prepared by mixing rat tail type I collagen, hydroxyapatite microparticles and MSCs. After polymerization gels were kept in culture while gel contraction and mechanical properties were studied. In parallel, cell viability and morphology were analyzed. Gels became free-floating gels contracted from day 3, only in the presence of cells. A linear rapid contraction phase was observed until day 7, then a very slow contraction phase took place. The incorporation of hydroxyapatite improved gel stability and mechanical properties. Cells were randomly distributed on the gel and a few dead cells were observed all over the experiment. This study shows the feasibility and biocompatibility of hydroxyapatite supplemented collagen gels for the culture of mesenchymal stem cells that could be used as scaffolds for cell delivery in osteoarticular regenerative medicine.


Asunto(s)
Materiales Biocompatibles/química , Técnicas de Cultivo de Célula , Colágeno/química , Durapatita/química , Células Madre Mesenquimatosas/fisiología , Andamios del Tejido/química , Animales , Células de la Médula Ósea/fisiología , Forma de la Célula , Supervivencia Celular/fisiología , Colágeno Tipo I/química , Estudios de Factibilidad , Humanos , Hidrogeles/química , Fenómenos Mecánicos , Tamaño de la Partícula , Polimerizacion , Ratas , Propiedades de Superficie , Factores de Tiempo , Ingeniería de Tejidos
11.
Curr Pharm Biotechnol ; 13(15): 2682-91, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23072395

RESUMEN

Injuries to articular cartilage are one of the most challenging issues of musculoskeletal medicine due to the poor intrinsic ability of this tissue for repair. Despite progress in orthopaedic surgery, cell-based surgical therapies such as autologous chondrocyte transplantation (ACT) have been in clinical use for cartilage repair for over a decade but this approach has shown mixed results. Moreover, the lack of efficient modalities of treatment for large chondral defects has prompted research on cartilage tissue engineering combining cells, scaffold materials and environmental factors. This paper focuses on the main parameters in tissue engineering and in particular, on the potential of mesenchymal stem cells (MSCs) as an alternative to cells derived from patient tissues in autologous transplantation and tissue engineering. We discussed the prospects of using autologous chondrocytes or MSCs in regenerative medicine and summarized the advantages and disadvantages of these cells in articular cartilage engineering.


Asunto(s)
Cartílago Articular , Células Madre Mesenquimatosas , Ingeniería de Tejidos/métodos , Humanos , Trasplante Autólogo
12.
Biomed Mater Eng ; 22(1-3): 3-16, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22766697

RESUMEN

Human tissues don't regenerate spontaneously, explaining why regenerative medicine and cell therapy represent a promising alternative treatment (autologous cells or stem cells of different origins). The principle is simple: cells are collected, expanded and introduced with or without modification into injured tissues or organs. Among middle-term therapeutic applications, cartilage defects, bone repair, cardiac insufficiency, burns, liver or bladder, neurodegenerative disorders could be considered.


Asunto(s)
Medicina Regenerativa/métodos , Trasplante de Células Madre , Células Madre/citología , Ingeniería de Tejidos/métodos , Animales , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Humanos , Mecanotransducción Celular , Células Madre/metabolismo , Andamios del Tejido/química
13.
Biomed Mater Eng ; 22(1-3): 159-62, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22766715

RESUMEN

For this study, we have considered a new large field of view imaging dedicated to matrix collagen (no stained samples). To integrate a multidimensional scale (non-sliced samples), a femtosecond oscillator (two photon excitation laser) has been coupled with a large field optical setup to collect SHG signal. We introduced an index (F-SHG) based on decay time response measured by TCSPC for, respectively, Fluorescence (F) and Second Harmonic Generation (SHG) values. For samples where protein collagen is the major component of extracellular matrix (skin) or not (nacre), we compared the index distribution (from 2 to 12) obtained with large field optical setup. In this work, we showed for the first time that multiscale large field imaging combined to multimodality approaches (SHG-TCSPC) could be an innovative and non invasive technique to detect and identify some biological interest molecules (collagen) in biomedical topics.


Asunto(s)
Colágeno/ultraestructura , Matriz Extracelular/ultraestructura , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Nácar/análisis , Pinctada/ultraestructura , Piel/ultraestructura , Animales , Colágeno/análisis , Matriz Extracelular/química , Masculino , Pinctada/química , Ratas , Piel/química
14.
Biomed Mater Eng ; 20(3): 127-33, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20930320

RESUMEN

Tissue engineering is a multidisciplinary field that applies the principles of engineering, life sciences, cell and molecular biology toward the development of biological substitutes that restore, maintain, and improve tissue function. In Western Countries, tissues or cells management for clinical uses is a medical activity governed by different laws. Three general components are involved in tissue engineering: (1) reparative cells that can form a functional matrix; (2) an appropriate scaffold for transplantation and support; and (3) bioreactive molecules, such as cytokines and growth factors that will support and choreograph formation of the desired tissue. These three components may be used individually or in combination to regenerate organs or tissues. Thus the growing development of tissue engineering needs to solve four main problems: cells, engineering development, grafting and safety studies.


Asunto(s)
Cartílago/citología , Cartílago/crecimiento & desarrollo , Técnicas de Cultivo de Célula/tendencias , Regeneración/fisiología , Ingeniería de Tejidos/tendencias , Animales , Humanos
15.
Biomed Mater Eng ; 20(3): 167-74, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20930324

RESUMEN

Cartilage tissue engineering gives the ability to product adaptable neocartilage to lesion with autologous cells. Our work aimed to develop a stratified scaffold with a simple and progressive spraying build-up to mimic articular cartilage environment. An Alginate/Hyaluronic Acid (Alg/HA) hydrogel seeded with human Mesenchymal Stem Cells (hMSC) was construct by spray. First, cells repartition and actin organization were study with confocal microscopy. Then, we analyzed cells viability and finally, metabolic activity. Our results indicated a homogenous cells repartition in the hydrogel and a pericellular actin repartition. After 3 days of culture, we observed about 52% of viable cells in the scaffold. Then, from day 7 until the end of culture (D28), the proportion of living cells and their metabolic activity increased, what indicates that culture conditions are not harmful for the cells. We report here that sprayed method allowed to product a scaffold with hMSCs that confer a favorable environment for neocartilage construction: 3D conformation and ability of cells to increase their metabolic activity, therefore with few impact on hMSCs.


Asunto(s)
Materiales Biocompatibles/química , Cartílago/citología , Cartílago/crecimiento & desarrollo , Condrocitos/citología , Células Madre Mesenquimatosas/citología , Ingeniería de Tejidos/instrumentación , Andamios del Tejido , Diferenciación Celular , Células Cultivadas , Condrocitos/fisiología , Diseño de Equipo , Humanos , Ensayo de Materiales , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/fisiología
16.
Biomed Mater Eng ; 20(3): 227-33, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20930332

RESUMEN

The FoxO family of Forkhead transcription factors functions at the interface of tumor suppression, energy metabolism and organismal longevity. FoxO factors are key downstream targets of insulin, growth factor, nutrient and oxidative stress stimuli that coordinate a wide-range of cellular outputs. These transcription factors could participate in the regulation of different phenomena found in the osteoarthritis pathology, like apoptosis, chondrocyte proliferation, cell dedifferentiation or resistance to oxidative stress. Moreover, we found recently that FoxO transcription factors could be involved on Diacerhein mode of action, a drug that reduces the IL-1ß deleterious effects on osteoarthritis cartilage through inhibition of the expression of degrading enzymes. It could explain the downregulated proliferation and the increased p27 expression observed on human osteoarthritic chondrocytes in the presence of Diacerhein.


Asunto(s)
Antraquinonas/farmacología , Cartílago Articular/metabolismo , Factores de Transcripción Forkhead/metabolismo , Modelos Biológicos , Osteoartritis/tratamiento farmacológico , Osteoartritis/metabolismo , Animales , Antraquinonas/uso terapéutico , Cartílago Articular/efectos de los fármacos , Humanos
17.
Lancet ; 374(9703): 1786-91, 2009 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-19914707

RESUMEN

Mass gatherings of people challenge public health capacities at host locations and the visitors' places of origin. Hajj--the yearly pilgrimage by Muslims to Saudi Arabia--is one of the largest, most culturally and geographically diverse mass gatherings in the world. With the 2009 pandemic influenza A H1N1 and upcoming Hajj, the Saudi Arabian Ministry of Health (MoH) convened a preparedness consultation in June, 2009. Consultants from global public health agencies met in their official capacities with their Saudi Arabian counterparts. The MoH aimed to pool and share public health knowledge about mass gatherings, and review the country's preparedness plans, focusing on the prevention and control of pandemic influenza. This process resulted in several practical recommendations, many to be put into practice before the start of Hajj and the rest during Hajj. These preparedness plans should ensure the optimum provision of health services for pilgrims to Saudi Arabia, and minimum disease transmission on their return home. Review of the implementation of these recommendations and their effect will not only inform future mass gatherings in Saudi Arabia, but will also strengthen preparedness efforts in other settings.


Asunto(s)
Control de Enfermedades Transmisibles/organización & administración , Brotes de Enfermedades/prevención & control , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana/prevención & control , Islamismo , Viaje , Implementación de Plan de Salud/organización & administración , Humanos , Gripe Humana/epidemiología , Gripe Humana/transmisión , Guías de Práctica Clínica como Asunto , Arabia Saudita
19.
Biomed Mater Eng ; 19(4-5): 301-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20042797

RESUMEN

In the last years, there were many studies based on the use of human bone marrow mesenchymal stem cells (hMSCs) in cell therapy and tissue engineering. Although hMSCs can be easily obtained and expanded in culture, a large number of cells are often needed. The expansion of hMSCs depends on the culture conditions, such as media, cell density or culture flasks. Moreover, growth factors are often added to improve cell proliferation. In this study, we compared the effect of two culture media (DMEM and alpha-MEM), two culture flasks (75 or 25 cm2) and two different mononuclear cell seeding densities (1 x 10(4) or 5 x 10(4) MNC/cm2) on the isolation of hMSCs from bone marrow samples and analyzed if the isolation conditions affected the expansion of these cells in the first two passages. Experiments were performed without the addition of exogenous growth factors. Our results showed that alpha-MEM is the optimal culture medium for both, isolation and expansion of mesenchymal stem cells. Moreover, the cell seeding density of 50,000 MNC/cm2 in 25 cm2 culture flasks seems to be the best condition for the isolation step.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Separación Celular/métodos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Ingeniería de Tejidos/métodos , Diferenciación Celular , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Humanos , Manejo de Especímenes/métodos
20.
Biomed Mater Eng ; 18(4-5): 199-204, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19065022

RESUMEN

In tissue engineering, surface characteristics of a biomaterial are one of most important factors determining the compatibility with the environment. They influence attachment and growth of cells onto the material. In many cases, the surface should to be modified and engineered in the desired direction. The modification of non-adhesive surfaces with polyelectrolyte multilayer films (PMF) was recently depicted as a powerful technique to promote the growth of different cell lines. In this study, we evaluated the possible use of two different PMF as surface modification for the culture of mesenchymal stem cells (MSC). We used two types of PMF which differed by the nature of the initial anchoring layer which was poly(ethylenimine) (PEI) or poly(allylamine hydrochloride) (PAH). This initial polyelectrolytes adsorption was followed by the alternated deposition of poly(sodium 4-styrenesulfonate) (PSS) and (PAH) in order to obtain a PEI-(PSS-PAH)(3) film or a PAH-(PSS-PAH)(3) film. In order to control the behaviour of MSC, the cell viability was evaluated by Alamar Blue assay and the actin cytoskeleton was labelled and visualised in a confocal microscope. The behaviour of cells on the two PMF was compared to cells cultivated on surfaces treated with fibronectin. The results showed that PAH-(PSS-PAH)(3) PMF improve the growth of cells, inducing a higher cell viability compared to PEI-(PSS-PAH)(3) PMF and fibronectin at 2, 3 and 7 days of culture. Moreover, those cells showed a well-organized actin cytoskeleton. In conclusion, PAH-(PSS-PAH)(3) polyelectrolyte multilayer film seems to constitute an excellent material for MSC seeding.


Asunto(s)
Materiales Biocompatibles/química , Técnicas de Cultivo de Célula/métodos , Membranas Artificiales , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Ingeniería de Tejidos/métodos , Adhesión Celular/fisiología , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Humanos , Ensayo de Materiales , Propiedades de Superficie
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