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1.
Avian Dis ; 67(4): 326-339, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38300654

RESUMEN

Necrotic enteritis (NE) continues to be a significant burden to the poultry industry, compounded by pressure to reduce antibiotic use. Researchers use NE-challenge models to study the infection biology of NE and as screening tools to develop potential novel interventions. Currently, data are limited comparing such models between research establishments, and few indicate which quantitative metrics provide the most accurate measure for determining the efficacy of interventions. We compared data from 10 independent NE-challenge trials incorporating six challenge models employed in four geographical regions to determine the extent of variability in bird responses and to determine, using principal component analysis (PCA), which variables discriminated most effectively between nonchallenged control (NC) and challenged control (CC) groups. Response variables related to growth performance (weight gain, feed intake, feed conversion), health (mortality, lesion scores, NE induction rate), and, in three trials only, gut integrity (tight junction protein claudin-1, claudin-2, and zonula occludens-1 expression, coccidia counts, and intestinal permeability [assessed by FITC-dextran assay]). Treatments included a CC, which varied between trials (for example, in Eimeria predisposition, Clostridium perfringens strain, and days of inoculation), and a NC. The degree of response to challenge in CC birds varied significantly among models and trials. In all trials, lesion scores 1 to 4 days postchallenge were increased in CC vs. NC birds and varied both within and among models (by 0.29-1.17 points and 0.05-2.50 points, respectively). In addition, NE-related mortality at day 28 was increased in CC vs. NC, both within and among models (by 1.79%-4.72% and 0.02%-16.70%, respectively), and final (day 35 or 42) body weight was reduced by 3.9%-14.4% and overall FCR increased by up to 27% across trials (P , 0.05). A PCA on the combined dataset including only performance indicators failed to adequately differentiate NC and CC groups. However, the combination of performance and gut integrity variables and standardization of data by trial and phase achieved greater resolution between groups. This indicated that the inclusion of both types of variables in future NE-challenge studies would enable the generation of more robust predictions about intervention efficacy from different types of infection models. A final PCA based on a subset of key indicator variables, including body weight, feed intake, feed conversion ratio, mortality, and lesion score, achieved a good level of separation between NC and CC status of birds and could, with further research, be a useful supplement to existing approaches for assessing and predicting the NE status of birds in the field.


Determinación del impacto variable de la enteritis necrótica mediante indicadores de rendimiento y salud en modelos de infección de pollos de engorde. La enteritis necrótica (EN) sigue siendo un problema importante para la industria avícola, que se ha agudizado por la presión para reducir el uso de antibióticos. Los investigadores utilizan modelos de desafío de enteritis necrótica para estudiar la biología de la infección de este problema y como herramientas de detección para desarrollar posibles intervenciones novedosas. Actualmente, los datos que comparan dichos modelos entre grupos de investigación son limitados y pocos indican qué métricas cuantitativas proporcionan la medida más precisa para determinar la eficacia de las intervenciones. Comparamos datos de 10 ensayos independientes de desafío para enteritis necrótica que incorporan seis modelos de desafío empleados en cuatro regiones geográficas para determinar el grado de variabilidad en las respuestas de las aves y determinar, utilizando el análisis de componentes principales (PCA), qué variables discriminaron más efectivamente entre el control no desafiado (NC) y grupos de control desafiados (CC). Variables de respuesta relacionadas con el rendimiento del crecimiento (aumento de peso, consumo de alimento, conversión alimenticia), salud (mortalidad, puntuaciones de lesiones, tasa de inducción de enteritis necrótica) y, en sólo tres ensayos, la integridad intestinal (proteína de unión estrecha claudina-1, claudina-2, y expresión de zonula occludens-1, recuentos de coccidias y permeabilidad intestinal [evaluada mediante ensayo FITC-dextrano]). Los tratamientos incluyeron un control desafiado, que fue variable entre los ensayos (por ejemplo, en la predisposición a Eimeria, la cepa de Clostridium perfringens y los días de inoculación) y un control no desafiado. El grado de respuesta al desafío en aves del grupo control desafiado varió significativamente entre modelos y ensayos. En todos los ensayos, las puntuaciones de lesiones de 1 a 4 días después del desafío aumentaron en las aves del grupo control desafiado en comparación con el control no desafiado y variaron tanto dentro como entre los modelos (entre 0.29 y 1.17 puntos y entre 0.05 y 2.50 puntos, respectivamente). Además, la mortalidad relacionada con enteritis necrótica en el día 28 aumentó en el control desafiado en comparación con el control no desafiado, tanto dentro como entre modelos (entre un 1.79% y un 4.72% y entre un 0.02% y un 16.70%, respectivamente), y el peso corporal final (día 35 o 42). se redujo entre un 3.9% y un 14.4% y la conversión alimenticia en general aumentó hasta un 27% en todos los ensayos (P ,0.05). El análisis de componentes principales sobre el conjunto de datos combinado que incluye solo indicadores de desempeño no logró diferenciar adecuadamente los grupos control no desafiado y desafiado. Sin embargo, la combinación de variables de rendimiento e integridad intestinal y la estandarización de los datos por ensayo y fase lograron una mayor resolución entre los grupos. Esto indicó que la inclusión de ambos tipos de variables en futuros estudios de desafío para enteritis necrótica permitiría la generación de predicciones más sólidas sobre la eficacia de la intervención a partir de diferentes tipos de modelos de infección. Un análisis de componentes principales final basado en un subconjunto de variables indicadoras clave, incluido el peso corporal, el consumo de alimento, el índice de conversión alimenticia, la mortalidad y la puntuación de las lesiones, logró un buen nivel de separación entre el estado de las aves no desafiadas y desafiadas y podría, con más investigación, ser un complemento útil a los enfoques existentes para evaluar y predecir el estado de enteritis necrótica de las aves en el campo.


Asunto(s)
Enteritis , Enfermedades de las Aves de Corral , Animales , Pollos , Antibacterianos , Peso Corporal , Enteritis/veterinaria
2.
Mater Sci Eng C Mater Biol Appl ; 126: 112160, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34082965

RESUMEN

3D-bioprinting is an emerging technology of high potential in tissue engineering (TE), since it shows effective control over scaffold fabrication and cell distribution. Biopolymers such as alginate (Alg), nanofibrillated cellulose (NC) and hyaluronic acid (HA) offer excellent characteristics for use as bioinks due to their excellent biocompatibility and rheological properties. Cell incorporation into the bioink requires sterilisation assurance, and autoclave, ß-radiation and γ-radiation are widely used sterilisation techniques in biomedicine; however, their use in 3D-bioprinting for bioinks sterilisation is still in their early stages. In this study, different sterilisation procedures were applied on NC-Alg and NC-Alg-HA bioinks and their effect on several parameters was evaluated. Results demonstrated that NC-Alg and NC-Alg-HA bioinks suffered relevant rheological and physicochemical modifications after sterilisation; yet, it can be concluded that the short cycle autoclave is the best option to sterilise both NC-Alg based cell-free bioinks, and that the incorporation of HA to the NC-Alg bioink improves its characteristics. Additionally, 3D scaffolds were bioprinted and specifically characterized as well as the D1 mesenchymal stromal cells (D1-MSCs) embedded for cell viability analysis. Notably, the addition of HA demonstrates better scaffold properties, together with higher biocompatibility and cell viability in comparison with the NC-Alg scaffolds. Thus, the use of MSCs containing NC-Alg based scaffolds may become a feasible tissue engineering approach for regenerative medicine.


Asunto(s)
Bioimpresión , Ingeniería de Tejidos , Alginatos , Ácido Hialurónico , Impresión Tridimensional , Esterilización , Andamios del Tejido
3.
Mater Sci Eng C Mater Biol Appl ; 122: 111933, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33641924

RESUMEN

The most pressing need in cartilage tissue engineering (CTE) is the creation of a biomaterial capable to tailor the complex extracellular matrix of the tissue. Despite the standardized used of polycaprolactone (PCL) for osteochondral scaffolds, the pronounced stiffness mismatch between PCL scaffold and the tissue it replaces remarks the biomechanical incompatibility as main limitation. To overcome it, the present work was focused in the design and analysis of several geometries and pore sizes and how they affect cell adhesion and proliferation of infrapatellar fat pad-derived mesenchymal stem cells (IPFP-MSCs) loaded in biofabricated 3D thermoplastic scaffolds. A novel biomaterial for CTE, the 1,4-butanediol thermoplastic polyurethane (b-TPUe) together PCL were studied to compare their mechanical properties. Three different geometrical patterns were included: hexagonal (H), square (S), and, triangular (T); each one was printed with three different pore sizes (PS): 1, 1.5 and 2 mm. Results showed differences in cell adhesion, cell proliferation and mechanical properties depending on the geometry, porosity and type of biomaterial used. Finally, the microstructure of the two optimal geometries (T1.5 and T2) was deeply analyzed using multiaxial mechanical tests, with and without perimeters, µCT for microstructure analysis, DNA quantification and degradation assays. In conclusion, our results evidenced that IPFP-MSCs-loaded b-TPUe scaffolds had higher similarity with cartilage mechanics and T1.5 was the best adapted morphology for CTE.


Asunto(s)
Células Madre Mesenquimatosas , Ingeniería de Tejidos , Cartílago , Adhesión Celular , Proliferación Celular , Poliésteres , Porosidad , Andamios del Tejido
4.
FEBS J ; 287(22): 4933-4951, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32144855

RESUMEN

Catalytic inhibition of topoisomerase II during G2 phase delays onset of mitosis due to the activation of the so-called decatenation checkpoint. This checkpoint is less known compared with the extensively studied G2 DNA damage checkpoint and is partially compromised in many tumor cells. We recently identified MCPH1 as a key regulator that confers cells with the capacity to adapt to the decatenation checkpoint. In the present work, we have explored the contributions of checkpoint kinase 1 (Chk1) and polo-like kinase 1 (Plk1), in order to better understand the molecular basis of decatenation checkpoint. Our results demonstrate that Chk1 function is required to sustain the G2 arrest induced by catalytic inhibition of Topo II. Interestingly, Chk1 loss of function restores adaptation in cells lacking MCPH1. Furthermore, we demonstrate that Plk1 function is required to bypass the decatenation checkpoint arrest in cells following Chk1 inhibition. Taken together, our data suggest that MCPH1 is critical to allow checkpoint adaptation by counteracting Chk1-mediated inactivation of Plk1. Importantly, we also provide evidence that MCPH1 function is not required to allow recovery from this checkpoint, which lends support to the notion that checkpoint adaptation and recovery are different mechanisms distinguished in part by specific effectors.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , ADN-Topoisomerasas de Tipo II/metabolismo , Mitosis/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Inhibidores de Topoisomerasa II/farmacología , Biocatálisis/efectos de los fármacos , Proteínas de Ciclo Celular/genética , Línea Celular , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Citometría de Flujo , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/genética , Células HEK293 , Células HeLa , Humanos , Immunoblotting , Mitosis/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Quinasa Tipo Polo 1
5.
Eur J Endocrinol ; 182(3): 351-361, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31961799

RESUMEN

Objective: To provide an overview of cognitive and motor outcome, and quality of life (QoL) in patients with congenital central hypothyroidism (CH-C). Design: Systematic review with individual patient data (IPD) meta-analysis. Methods: OVID MEDLINE, EMBASE and PsycInfo were searched from inception to June 11th, 2019. Studies in patients with CH-C, either isolated or with multiple pituitary hormone deficiency (MPHD), were included if CH-C patients could be separated from any additional patient groups. Primary outcomes were full-scale intelligence quotient (FSIQ) and motor outcome; secondary outcome was QoL. Following data-extraction, one-stage IPD meta-analysis was performed, fitting a linear mixed model with FSIQ as dependent variable. Random intercepts were fitted for each study. Results: Six studies measuring FSIQ were eligible for meta-analysis, comprising 30 CH-C patients (20 males; 27 MPHD patients). FSIQ range was wide (64-123). Mean weighted FSIQ was 97 (95% CI: 88-105). Twenty-seven percent had an FSIQ below 85 (≥1 s.d. below norm score), and 10% below 70 (≥2 s.d. below norm score). There was no significant association between FSIQ and sex or age. Age at treatment initiation was available from three studies only, thus impeding a reliable analysis of this parameter. Motor outcome and QoL were each studied in one study; no quantitative analyses could be performed for these outcomes. Conclusion: A wide range in FSIQ scores was observed in CH-C patients. Results should be interpreted with caution, because included patients mainly had MPHD and age at treatment initiation was unknown for the majority of patients.


Asunto(s)
Hipotiroidismo Congénito/psicología , Adolescente , Niño , Preescolar , Hipotiroidismo Congénito/tratamiento farmacológico , Hipotiroidismo Congénito/etiología , Femenino , Humanos , Hipopituitarismo/complicaciones , Pruebas de Inteligencia , Masculino , Calidad de Vida , Adulto Joven
6.
FASEB J ; 33(7): 8363-8374, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30964711

RESUMEN

Cellular checkpoints controlling entry into mitosis monitor the integrity of the DNA and delay mitosis onset until the alteration is fully repaired. However, this canonical response can weaken, leading to a spontaneous bypass of the checkpoint, a process referred to as checkpoint adaptation. Here, we have investigated the contribution of microcephalin 1 (MCPH1), mutated in primary microcephaly, to the decatenation checkpoint, a less-understood G2 pathway that delays entry into mitosis until chromosomes are properly disentangled. Our results demonstrate that, although MCPH1 function is dispensable for activation and maintenance of the decatenation checkpoint, it is required for the adaptive response that bypasses the topoisomerase II inhibition----mediated G2 arrest. MCPH1, however, does not confer adaptation to the G2 arrest triggered by the ataxia telangiectasia mutated- and ataxia telangiectasia and rad3 related-based DNA damage checkpoint. In addition to revealing a new role for MCPH1 in cell cycle control, our study provides new insights into the genetic requirements that allow cellular adaptation to G2 checkpoints, a process that remains poorly understood.-Arroyo, M., Kuriyama, R., Guerrero, I., Keifenheim, D., Cañuelo, A., Calahorra, J., Sánchez, A., Clarke, D. J., Marchal, J. A. MCPH1 is essential for cellular adaptation to the G2-phase decatenation checkpoint.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas del Citoesqueleto/metabolismo , Puntos de Control de la Fase G2 del Ciclo Celular , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteínas de Ciclo Celular/genética , Línea Celular Transformada , Proteínas del Citoesqueleto/genética , Humanos
7.
Epigenetics Chromatin ; 12(1): 18, 2019 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-30871586

RESUMEN

BACKGROUND: The genome of some vole rodents exhibit large blocks of heterochromatin coupled to their sex chromosomes. The DNA composition and transcriptional activity of these heterochromatin blocks have been studied, but little is known about their DNA replication dynamics and epigenetic composition. RESULTS: Here, we show prominent epigenetic marks of the heterochromatic blocks in the giant sex chromosomes of female Microtus cabrerae cells. While the X chromosomes are hypoacetylated and cytosine hypomethylated, they are either enriched for macroH2A and H3K27me3 typical for facultative heterochromatin or for H3K9me3 and HP1 beta typical for constitutive heterochromatin. Using pulse-chase replication labeling and time-lapse microscopy, we found that the heterochromatic block enriched for macroH2A/H3K27me3 of the X chromosome is replicated during mid-S-phase, prior to the heterochromatic block enriched for H3K9me3/HP1 beta, which is replicated during late S-phase. To test whether histone acetylation level regulates its replication dynamics, we induced either global hyperacetylation by pharmacological inhibition or by targeting a histone acetyltransferase to the heterochromatic region of the X chromosomes. Our data reveal that histone acetylation level affects DNA replication dynamics of the sex chromosomes' heterochromatin and leads to a global reduction in replication fork rate genome wide. CONCLUSIONS: In conclusion, we mapped major epigenetic modifications controlling the structure of the sex chromosome-associated heterochromatin and demonstrated the occurrence of differences in the molecular mechanisms controlling the replication timing of the heterochromatic blocks at the sex chromosomes in female Microtus cabrerae cells. Furthermore, we highlighted a conserved role of histone acetylation level on replication dynamics across mammalian species.


Asunto(s)
Arvicolinae/genética , Replicación del ADN , Epigénesis Genética , Heterocromatina/metabolismo , Histonas/metabolismo , Procesamiento Proteico-Postraduccional , Cromosoma X/metabolismo , Acetilación , Animales , Arvicolinae/metabolismo , ADN/metabolismo , Femenino
8.
Biochim Biophys Acta Mol Basis Dis ; 1865(6): 1067-1075, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30910703

RESUMEN

Osteoarthritis (OA) is a joint disorder that is highly extended in the global population. Several researches and therapeutic strategies have been probed on OA but without satisfactory long-term results in joint replacement. Recent evidences show how the cartilage biomechanics plays a crucial role in tissue development. This review describes how physics alters cartilage and its extracellular matrix (ECM); and its role in OA development. The ECM of the articular cartilage (AC) is widely involved in cartilage turnover processes being crucial in regeneration and joint diseases. We also review the importance of physicochemical pathways following the external forces in AC. Moreover, new techniques probed in cartilage tissue engineering for biomechanical stimulation are reviewed. The final objective of these novel approaches is to create a cellular implant that maintains all the biochemical and biomechanical properties of the original tissue for long-term replacements in patients with OA.


Asunto(s)
Fenómenos Biomecánicos/fisiología , Cartílago Articular/fisiología , Matriz Extracelular/fisiología , Osteoartritis/fisiopatología , Medicina Regenerativa/métodos , Cartílago Articular/citología , Condrocitos/citología , Matriz Extracelular/metabolismo , Humanos , Modelos Biológicos , Medicina Regenerativa/tendencias , Ingeniería de Tejidos/métodos , Ingeniería de Tejidos/tendencias
9.
Eur Cell Mater ; 37: 186-213, 2019 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-30889270

RESUMEN

Hyaluronic acid (HA), as one of the main components of the extracellular matrix (ECM), plays a significant role in a multitude of biological processes involving cell migration, proliferation, differentiation, wound healing and inflammation. Thanks to its excellent biocompatibility, biodegradability and hygroscopic properties, HA has been used in its natural form for joint lubrication and ocular treatment. The chemical structure of HA can be easily modified by direct reaction with its carboxyl and hydroxyl groups. Recently, HA derivatives have been synthesised with the aim of developing HA-based materials with increased mechanical strength, improved cell interactions and reduced biodegradation and studied for regenerative medicine purposes, including cell therapy and tissue engineering. In this context, the present manuscript reviews HA applications from a basic point of view - including chemical modifications and cellular biology aspects related to clinical translation - and future perspectives of using biofabrication technologies for regenerative medicine. A detailed description of current clinical trials, testing advanced therapies based on combination of stem cells and HA formulations, is included. The final goal was to offer an integral portrait and a deeper comprehension of the current applications of HA from bench to bedside.


Asunto(s)
Ensayos Clínicos como Asunto , Ácido Hialurónico/farmacología , Trasplante de Células Madre , Células Madre/citología , Ingeniería de Tejidos/métodos , Humanos , Ácido Hialurónico/química , Nanopartículas/química
10.
Exp Biol Med (Maywood) ; 244(1): 13-21, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30630373

RESUMEN

IMPACT STATEMENT: 3D bioprinting represents a novel advance in the area of regenerative biomedicine and tissue engineering for the treatment of different pathologies, among which are those related to cartilage. Currently, the use of different thermoplastic polymers, such as PLA or PCL, for bioprinting processes presents an important limitation: the high temperatures that are required for extrusion affect the cell viability and the final characteristics of the construct. In this work, we present a novel bioprinting process called volume-by-volume (VbV) that allows us to preserve cell viability after bioprinting. This procedure allows cell injection at a safe thermoplastic temperature, and also allows the cells to be deposited in the desired areas of the construct, without the limitations caused by high temperatures. The VbV process could make it easier to bring 3D bioprinting into the clinic, allowing the generation of tissue constructs with polymers that are currently approved for clinical use.


Asunto(s)
Bioimpresión/métodos , Cartílago/citología , Condrocitos/citología , Bioimpresión/instrumentación , Biotecnología/instrumentación , Biotecnología/métodos , Cartílago/fisiología , Técnicas de Cultivo de Célula , Proliferación Celular , Supervivencia Celular , Condrocitos/fisiología , Calor , Humanos , Impresión Tridimensional/instrumentación , Regeneración , Ingeniería de Tejidos/métodos , Andamios del Tejido
11.
Pediatr Blood Cancer ; 66(1): e27419, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30152099

RESUMEN

BACKGROUND: Adaptive behavior, i.e., the performance on daily activities required for personal and social independence, is essential to estimate in children with low-grade glioma (LGG) since most of them are long-term survivors. Our aim was to investigate adaptive behavior in children with LGG. METHODS: In a cross-sectional study, adaptive behavior was assessed using the paper pencil version of the Parent Form of the Vineland Adaptive Behavior Scales 2nd edition (VABS-II) testing communication, daily living skills, social skills, and motor skills. Scores of children with LGG, younger than 20 years, and diagnosed between 2004 and 2014 were compared with family controls. Correlations between clinical variables and adaptive behavior were explored. RESULTS: Fifty-six children with LGG (median age, 12.1 years; 52% male) and 46 controls (median age, 11.0 years; 43% male) were included in the analyses. Compared with controls, the LGG group was more impaired on total adaptive behavior, communication, and motor skills and in the subdomain gross motor skills (effect sizes d, 0.64-0.86, P < 0.003). Younger age at diagnosis (r = -0.357, P < 0.01) and chemotherapy (r = -0.342, P < 0.05) were associated with poorer motor skills. Residual disease was associated with poorer total adaptive behavior (r = -0.282, P < 0.05). No other significant correlations were found. CONCLUSION: At the group level, adaptive functioning of children with LGG is impaired compared with family controls. Regular structured monitoring of adaptive behavior is recommended to be able to define the needs for tailored rehabilitation in daily life at home as well as at school.


Asunto(s)
Actividades Cotidianas , Adaptación Psicológica , Comunicación , Glioma/fisiopatología , Trastornos de la Destreza Motora/etiología , Destreza Motora/fisiología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , Estudios Transversales , Femenino , Estudios de Seguimiento , Glioma/complicaciones , Glioma/psicología , Humanos , Lactante , Masculino , Trastornos de la Destreza Motora/patología , Clasificación del Tumor , Adulto Joven
12.
J Eur Acad Dermatol Venereol ; 33(3): 484-496, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30520159

RESUMEN

Regenerative medicine and tissue engineering (TE) have experienced significant advances in the development of in vitro engineered skin substitutes, either for replacement of lost tissue in skin injuries or for the generation of in vitro human skin models to research. However, currently available skin substitutes present different limitations such as expensive costs, abnormal skin microstructure and engraftment failure. Given these limitations, new technologies, based on advanced therapies and regenerative medicine, have been applied to develop skin substitutes with several pharmaceutical applications that include injectable cell suspensions, cell-spray devices, sheets or 3Dscaffolds for skin tissue regeneration and others. Clinical practice for skin injuries has evolved to incorporate these innovative applications to facilitate wound healing, improve the barrier function of the skin, prevent infections, manage pain and even to ameliorate long-term aesthetic results. In this article, we review current commercially available skin substitutes for clinical use, as well as the latest advances in biomedical and pharmaceutical applications used to design advanced therapies and medical products for wound healing and skin regeneration. We highlight the current progress in clinical trials for wound healing as well as the new technologies that are being developed and hold the potential to generate skin substitutes such as 3D bioprinting-based strategies.


Asunto(s)
Dermis Acelular , Regeneración , Fenómenos Fisiológicos de la Piel , Piel Artificial , Cicatrización de Heridas , Materiales Biocompatibles , Humanos , Trasplante de Piel , Ingeniería de Tejidos
13.
Eur Cell Mater ; 35: 209-224, 2018 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-29652075

RESUMEN

The success of cell-based approaches for the treatment of cartilage defects requires an optimal autologous cell source with chondrogenic differentiation ability that maintains its differentiated properties and stability following implantation. The objective of this study was to compare the chondrogenic capacity of mesenchymal stem cells (MSCs) isolated from lipoaspirates (ASCs) and the infrapatellar fat pad (IFPSCs) of osteoarthritic patients and treated with transforming growth factor (TGF)-ß family-related growth factors. Cells were cultured for 6 weeks in a 3D pellet culture system with the chimeric activin A/bone morphogenic protein (BMP)-2 ligand (AB235), the chimeric nodal/BMP-2 ligand (NB260) or BMP-2. To investigate the stability of the new cartilage, ASCs-treated pellets were transplanted subcutaneously into severe combined immunodeficiency (SCID) mice. Histological and immunohistochemical assessment confirmed that the growth factors induced cartilage differentiation in both isolated cell types. However, reverse transcription-quantitative PCR results showed that ASCs presented a higher chondrogenic potential than IFPSCs. In vivo results revealed that AB235-treated ASCs pellets were larger in size and could form stable cartilage-like tissue as compared to NB260-treated pellets, while BMP-2-treated pellets underwent calcification. The chondrogenic induction of ASCs by AB235 treatment was mediated by SMAD2/3 activation, as proved by immunofluorescence analysis. The results of this study indicated that the combination of ASCs and AB235 might lead to a cell-based cartilage regeneration treatment.


Asunto(s)
Tejido Adiposo/patología , Diferenciación Celular/efectos de los fármacos , Separación Celular , Condrogénesis/efectos de los fármacos , Lipectomía , Osteoartritis/patología , Células Madre/patología , Factor de Crecimiento Transformador beta/farmacología , Anciano , Animales , Femenino , Humanos , Masculino , Ratones SCID , Persona de Mediana Edad , Fenotipo , Proteínas Smad/metabolismo , Trasplante de Células Madre
14.
Colloids Surf B Biointerfaces ; 165: 103-110, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29471218

RESUMEN

Liquid lipid nanocapsules (LLN) represent a promising new generation of drug-delivery systems. They can carry hydrophobic drugs in their oily core, but the composition and structure of the surrounding protective shell determine their capacity to survive in the circulatory system and to achieve their goal: penetrate tumor cells. Here, we present a study of LLN covered by the protein human serum albumin (HSA) and loaded with curcumin as a hydrophobic model drug. A cross-linking procedure was performed to further strengthen the protective protein layer. Physicochemical properties and release kinetics of the nanocapsules were investigated, and cellular uptake and killing capacity were evaluated on the human breast-cancer line MCF-7. The nanocapsules exhibited a half maximal inhibitory concentration (IC50) capacity similar to that of free curcumin, but avoiding problems associated with excipients, and displayed an outstanding uptake performance, entering cells massively in less than 1 min.


Asunto(s)
Neoplasias de la Mama/metabolismo , Endocitosis , Lípidos/química , Nanocápsulas/química , Albúmina Sérica/metabolismo , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cumarinas/química , Curcumina/farmacología , Curcumina/uso terapéutico , Liberación de Fármacos , Femenino , Humanos , Células MCF-7 , Nanocápsulas/ultraestructura , Tiazoles/química
15.
Sci Rep ; 7(1): 13019, 2017 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-29026105

RESUMEN

MCPH1 gene, mutated in primary microcephaly, regulates cell progression into mitosis. While this role has been extensively investigated in the context of DNA damage, its function during unperturbed cell cycles has been given less attention. Here we have analyzed the dynamics of chromosome condensation and cell cycle progression in MCPH1 deficient cells under undamaging conditions. Our study demonstrates that chromosome condensation is uncoupled from cell cycle progression when MCPH1 function is lacking, resulting in cells that prematurely condense their chromosomes during mid G2-phase and delay decondensation at the completion of mitosis. However, mitosis onset occurs on schedule in MCPH1 deficient cells. We also revealed active Cdk1 to be mandatory for the premature onset of chromosome condensation during G2 and the maintenance of the condensed state thereafter. Interestingly, a novel cellular phenotype was observed while monitoring cell cycle progression in cells lacking MCPH1 function. Specifically, completion of chromosome alignment at the metaphase plate was significantly delayed. This deficiency reveals that MCPH1 is required for efficient chromosome biorientation during mitosis.


Asunto(s)
Cromosomas Humanos/genética , Microcefalia/genética , Mitosis/genética , Mutación/genética , Proteínas del Tejido Nervioso/genética , Proteína Quinasa CDC2/metabolismo , Proteínas de Ciclo Celular , Proteínas del Citoesqueleto , Células HeLa , Humanos , Profase , ARN Interferente Pequeño/metabolismo
16.
Neurochirurgie ; 63(4): 291-296, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28870453

RESUMEN

INTRODUCTION: Spinal cord tumors in children (SCTC) are rare with a frequent diagnostic delay. Its management is multidisciplinary and challenging due to functional implications. The position of surgery is now better established but the role and timing of chemotherapy (CT) and radiotherapy (RT) still remains under debate. Adverse effects of treatments are important to be taken into account, in the follow-up of these children. The aim of this paper was to present a series of 21 cases of SCTC treated at the same institution, to briefly present clinical features, treatments and outcome, with a special focus on spinal deformities in children with this condition. MATERIAL AND METHODS: Twenty-one consecutive SCTC were referred to our institution from 1990 to 2014. Data regarding age, sex, diagnostic delay, clinical examination, MRI, surgery, pathology, other treatment (CT and RT), orthopedic issues and follow-up of these children were retrospectively recorded. RESULTS: Mean age was 8years (standard deviation: 5.2years) (range: 4 months-17years). Mean diagnosis delay was 5.5 months (standard deviation: 6.5 months) (range: 0 days-18 months). All children (10 girls, 11 boys) were operated on (10 partial removals, 7 subtotal and 4 gross total removals) as first-line treatment. Pathological results showed 12 juvenile pilocytic astrocytomas, 1 grade III astrocytoma, 1 grade IV astrocytoma, 3 oligodendrogliomas, 2 ependymomas, 1 glioblastoma and 1 rhabdoid tumor. Fourteen children (66.7%) received additional treatment: 12 CT and 7 RT. Ten children had postoperative spinal deformities. Mean follow-up (FU) was 71 months (5 months-180 months), with a median FU at 60 months, where 8 tumor progressions and 4 deaths were observed. Overall, survival (at 5years) was 81% and progression free survival (at 5years) was 67%. CONCLUSION: Surgery is the goal standard for SCTC and the only appropriate treatment in cases of a low-grade lesion with stable disease on MR follow-up. Additional treatment must be reserved for high-grade lesions or tumor progression not attainable by a second look surgery. Spinal deformities are a frequent complication. Overall, survival and event free survival primarily depends on the pathology. Studies involving more centers are obligatory with the aim of collecting more cases and drawing more definitive conclusions regarding the management of these tumors.


Asunto(s)
Neoplasias de la Médula Espinal/diagnóstico , Neoplasias de la Médula Espinal/cirugía , Adolescente , Niño , Preescolar , Diagnóstico Tardío , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Procedimientos Neuroquirúrgicos/efectos adversos , Estudios Retrospectivos , Neoplasias de la Médula Espinal/mortalidad , Análisis de Supervivencia
17.
Cells Tissues Organs ; 204(3-4): 150-163, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28803246

RESUMEN

The treatment and regeneration of bone defects caused by traumatism or diseases have not been completely addressed by current therapies. Lately, advanced tools and technologies have been successfully developed for bone tissue regeneration. Functional scaffolding materials such as biopolymers and bioresorbable fillers have gained particular attention, owing to their ability to promote cell adhesion, proliferation, and extracellular matrix production, which promote new bone growth. Here, we present novel biofunctional scaffolds for bone regeneration composed of silk fibroin (SF) and ß-tricalcium phosphate (ß-TCP) and incorporating Sr, Zn, and Mn, which were successfully developed using salt-leaching followed by a freeze-drying technique. The scaffolds presented a suitable pore size, porosity, and high interconnectivity, adequate for promoting cell attachment and proliferation. The degradation behavior and compressive mechanical strengths showed that SF/ionic-doped TCP scaffolds exhibit improved characteristics for bone tissue engineering when compared with SF scaffolds alone. The in vitro bioactivity assays using a simulated body fluid showed the growth of an apatite layer. Furthermore, in vitro assays using human adipose-derived stem cells presented different effects on cell proliferation/differentiation when varying the doping agents in the biofunctional scaffolds. The incorporation of Zn into the scaffolds led to improved proliferation, while the Sr- and Mn-doped scaffolds presented higher osteogenic potential as demonstrated by DNA quantification and alkaline phosphatase activity. The combination of Sr with Zn led to an influence on cell proliferation and osteogenesis when compared with single ions. Our results indicate that biofunctional ionic-doped composite scaffolds are good candidates for further in vivo studies on bone tissue regeneration.


Asunto(s)
Materiales Biocompatibles/química , Huesos/efectos de los fármacos , Fosfatos de Calcio/química , Fibroínas/química , Materiales Biocompatibles/farmacología , Fenómenos Biomecánicos , Huesos/citología , Huesos/fisiología , Diferenciación Celular , Fibroínas/farmacología , Humanos , Ingeniería de Tejidos , Andamios del Tejido
18.
Expert Rev Mol Med ; 19: e9, 2017 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-28724458

RESUMEN

The protein kinase R (PKR, also called EIF2AK2) is an interferon-inducible double-stranded RNA protein kinase with multiple effects on cells that plays an active part in the cellular response to numerous types of stress. PKR has been extensively studied and documented for its relevance as an antiviral agent and a cell growth regulator. Recently, the role of PKR related to metabolism, inflammatory processes, cancer and neurodegenerative diseases has gained interest. In this review, we summarise and discuss the involvement of PKR in several cancer signalling pathways and the dual role that this kinase plays in cancer disease. We emphasise the importance of PKR as a molecular target for both conventional chemotherapeutics and emerging treatments based on novel drugs, and its potential as a biomarker and therapeutic target for several pathologies. Finally, we discuss the impact that the recent knowledge regarding PKR involvement in metabolism has in our understanding of the complex processes of cancer and metabolism pathologies, highlighting the translational research establishing the clinical and therapeutic potential of this pleiotropic kinase.


Asunto(s)
Metabolismo Energético , Neoplasias/metabolismo , eIF-2 Quinasa/metabolismo , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis/genética , Biomarcadores , Metabolismo Energético/efectos de los fármacos , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Transducción de Señal/efectos de los fármacos , eIF-2 Quinasa/antagonistas & inhibidores , eIF-2 Quinasa/genética
19.
Sci Rep ; 7: 39782, 2017 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-28051134

RESUMEN

Oncogenic microRNAs (miRs) have emerged as diagnostic biomarkers and novel molecular targets for anti-cancer drug therapies. Real-time quantitative PCR (qPCR) is one of the most powerful techniques for analyzing miRs; however, the use of unsuitable normalizers might bias the results. Tumour heterogeneity makes even more difficult the selection of an adequate endogenous normalizer control. Here, we have evaluated five potential referenced small RNAs (U6, rRNA5s, SNORD44, SNORD24 and hsa-miR-24c-3p) using RedFinder algorisms to perform a stability expression analysis in i) normal colon cells, ii) colon and breast cancer cell lines and iii) cancer stem-like cell subpopulations. We identified SNORD44 as a suitable housekeeping gene for qPCR analysis comparing normal and cancer cells. However, this small nucleolar RNA was not a useful normalizer for cancer stem-like cell subpopulations versus subpopulations without stemness properties. In addition, we show for the first time that hsa-miR-24c-3p is the most stable normalizer for comparing these two subpopulations. Also, we have identified by bioinformatic and qPCR analysis, different miR expression patterns in colon cancer versus non tumour cells using the previously selected suitable normalizers. Our results emphasize the importance of select suitable normalizers to ensure the robustness and reliability of qPCR data for analyzing miR expression.


Asunto(s)
MicroARNs/metabolismo , Neoplasias/patología , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Biología Computacional , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
20.
Neurochirurgie ; 62(1): 53-9, 2016 Feb.
Artículo en Francés | MEDLINE | ID: mdl-26657112

RESUMEN

INTRODUCTION: Ventriculoperitoneal shunting (VPS) is a treatment of the hydrocephalus that may dysfunction. The clinical presentation of shunt dysfunction is variable. We therefore decided to focus on the clinical presentation of VPS malfunction in children, as this condition requires immediate emergency treatment and because of the sometimes confusing signs of intracranial hypertension in a shunted child. MATERIALS AND METHODS: We searched PubMed with the following groups of keywords: (dysfunction OR blockage) AND shunting AND hydrocephalus; shunt complications AND hydrocephalus; hydrocephalus AND shunt AND malfunction. Articles dealing with ventriculo-atrial shunt were excluded. A total of 79 articles were retained for analysis (English and French). Case reports were excluded. RESULTS: The clinical presentation varies by age: vomiting and alterated level of consciousness are the most frequent signs in older children, whereas infants present more often with raised intracranial pressure symptoms such as nausea, vomiting, irritability and bulging fontanel. Drowsiness is a good predictor of VPS dysfunction. An asymptomatic presentation is rare but possible. Abdominal presentation is also possible, ranging from abdominal discomfort to peritonitis. Fever, occurring a short time after the last intervention, and irritability are good predictors of shunt infection. Pumping the chamber of the VPS has a weak positive predictive value (12%). Shunt dysfunction can lead to death, with an estimated mortality rate at 1% per year during the first years. CONCLUSION: It is essential to be aware of the variability of the clinical presentation of VPS dysfunction, because of the potential severity of this condition. Also it is important to pay attention to the comments of the parents, especially if the child experienced a previous shunt malfunction.


Asunto(s)
Falla de Equipo , Hidrocefalia/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/terapia , Derivación Ventriculoperitoneal/efectos adversos , Niño , Fiebre/complicaciones , Humanos , Hidrocefalia/complicaciones , Hidrocefalia/diagnóstico , Complicaciones Posoperatorias/diagnóstico , Derivación Ventriculoperitoneal/métodos , Vómitos/complicaciones
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