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1.
BMC Public Health ; 22(1): 1622, 2022 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-36028876

RESUMEN

BACKGROUND: During the 2020 COVID-19 pandemic, governments imposed numerous regulations to protect public health, particularly the (mandatory) use of face masks. However, the appropriateness and effectiveness of face mask regulations have been widely discussed, as is apparent from the divergent measures taken across and within countries over time, including mandating, recommending, and discouraging their use. In this study, we analyse how country-level policy stringency and individual-level predictors associate with face mask use during the early stages of the global COVID-19 pandemic. METHOD: First, we study how (self and other-related) risk perception, (direct and indirect) experience with COVID-19, attitude towards government and policy stringency shape face mask use. Second, we study whether there is an interaction between policy stringency and the individual-level variables. We conduct multilevel analyses exploiting variation in face mask regulations across countries and using data from approximately 7000 students collected in the beginning of the pandemic (weeks 17 through 19, 2020). RESULTS: We show that policy stringency is strongly positively associated with face mask use. We find a positive association between self-related risk perception and mask use, but no relationship of mask use with experience with COVID-19 and attitudes towards government. However, in the interaction analyses, we find that government trust and perceived clarity of communication moderate the link between stringency and mask use, with positive government perceptions relating to higher use in countries with regulations and to lower use in countries without regulations. CONCLUSIONS: We highlight that those countries that aim for widespread use of face masks should set strict measures, stress self-related risks of COVID-19, and use clear communication.


Asunto(s)
COVID-19 , Máscaras , Gobierno , Humanos , Pandemias , Percepción , Políticas , SARS-CoV-2
2.
Pers Individ Dif ; 179: 110925, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34866724

RESUMEN

During the 2020 COVID-19 pandemic, governments set recommendations and restrictions that have given rise to new situations that require residents to deliberate and respond nonautomatically. For highly impulsive individuals, dealing with these situations may be harder, as they tend to deliberate less about the consequences of their behaviors. In this study, we investigate the relationship between impulsivity and delay discounting on the one hand and compliance with COVID-19 restrictions on the other hand. We distinguish between compliance with social distancing measures and compliance with hygiene measures. Regression analyses of an international sample of 6759 students from seven European countries reveal that the self-reported personality construct of impulsivity is negatively related to both types of compliance behavior. However, and unexpectedly, we also find a weak positive association between the discount rate-as measured by a behavioral task-and compliance. Our study highlights the importance of individual differences in impulsivity in regard to compliance with public health measures during a pandemic.

3.
Eur Neurol ; 80(5-6): 289-294, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30783053

RESUMEN

INTRODUCTION: While there are several studies on reliability of telemedicine in assessing stroke scales, little is known about the validity of a general neurological examination performed via telemedicine. Therefore, we sought to test the agreement between bedside and remote examination in acute patients of the emergency room. METHODS: Acute patients at the emergency room of a 450-bed academic teaching hospital were included in this study. A clinical neurological examination consisting of 22 items was performed at bedside and also remotely via an audio-visual link by a different neurologist; both were experienced clinicians at the consultant level. Kappa statistics were calculated for each item of the examination. RESULTS: Forty three patients completed both examinations (mean age 58.3 years, 56% female). Patients were seen between 8 and 72 min after admission (mean 36.3 min). Total time for remote examination was 12.6 min (8-21 min) and 8.9 min (5-18 min) for bedside examination. K-coefficients ranged from 0.32 (muscle tone) - 0.82 (language) indicating a fair to excellent agreement in most items. CONCLUSIONS: Remote examination via an audio-visual link produces comparable results to bedside performance even in acute patients of the emergency room. Compared to the scarce data available, inter-observer agreement is about the same as that between 2 examiners at bedside. However, more studies on reliability and validity of clinical neurological examination are required.


Asunto(s)
Examen Neurológico/métodos , Neurología/métodos , Accidente Cerebrovascular/diagnóstico , Telemedicina/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neurólogos , Reproducibilidad de los Resultados
4.
Microb Ecol ; 65(4): 1052-67, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23563708

RESUMEN

The number of reported Vibrio-related wound infections associated with recreational bathing in Northern Europe has increased within the last decades. In order to study the health risk from potentially pathogenic Vibrio spp. in the central Wadden Sea, the seasonal and spatial distribution of Vibrio vulnificus, Vibrio parahaemolyticus, Vibrio alginolyticus and Vibrio cholerae were investigated at ten recreational beaches in this area over a 2-year period. V. alginolyticus and V. parahaemolyticus were found to be omnipresent all year round in the study area, while V. vulnificus occurrence was restricted to summer months in the estuaries of the rivers Ems and Weser. Multiple linear regression models revealed that water temperature is the most important determinant of Vibrio spp. occurrence in the area. Differentiated regression models showed a species-specific response to water temperature and revealed a particularly strong effect of even minor temperature increases on the probability of detecting V. vulnificus in summer. In sediments, Vibrio spp. concentrations were up to three orders of magnitude higher than in water. Also, V. alginolyticus and V. parahaemolyticus were found to be less susceptible towards winter temperatures in the benthic environment than in the water, indicating an important role of sediments for Vibrio ecology. While only a very small percentage of tested V. parahaemolyticus proved to be potentially pathogenic, the presence of V. vulnificus during the summer months should be regarded with care.


Asunto(s)
Agua de Mar/microbiología , Vibrio/aislamiento & purificación , Alemania , Mar del Norte , Estaciones del Año , Agua de Mar/química , Temperatura , Vibrio/clasificación , Vibrio/genética
5.
Front Psychol ; 13: 842590, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35310260

RESUMEN

In case of failure, entrepreneurs could endure various financial, psychological, and social costs. These intertwined costs could affect their learning from failure. All individuals do not react in the same way when dealing with adversity. Rather than focusing on (negative) consequences of business failure, we took a more positive approach by using the Conservation of Resources (COR) model theory to build our conceptual model. Psychological capital, which refers to "an individual's positive psychological state of development characterized by high levels of self-efficacy, optimism, hope, and resilience," could be considered as a resource to recover from entrepreneurial setbacks. We suggest that a high level of psychological capital plays a mediating role in the relationship between the negative consequences of failure and learning from failure. By learning from this experience, failed entrepreneurs will increase their intention to re-create a venture and pursue their entrepreneurial career. This theoretical research, by building a conceptual model based on resources, offers a more positive approach of entrepreneurial failure and investigates key psychological assets, such as psychological capital, that support the development of entrepreneurial resilience rather than the prevention of business failure.

6.
Proc Natl Acad Sci U S A ; 105(20): 7281-6, 2008 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-18490653

RESUMEN

Tissue engineering of large bone defects is approached through implantation of autologous osteogenic cells, generally referred to as multipotent stromal cells or mesenchymal stem cells (MSCs). Animal-derived MSCs successfully bridge large bone defects, but models for ectopic bone formation as well as recent clinical trials demonstrate that bone formation by human MSCs (hMSCs) is inadequate. The expansion phase presents an attractive window to direct hMSCs by pharmacological manipulation, even though no profound effect on bone formation in vivo has been described so far using this approach. We report that activation of protein kinase A elicits an immediate response through induction of genes such as ID2 and FosB, followed by sustained secretion of bone-related cytokines such as BMP-2, IGF-1, and IL-11. As a consequence, PKA activation results in robust in vivo bone formation by hMSCs derived from orthopedic patients.


Asunto(s)
Huesos/metabolismo , AMP Cíclico/metabolismo , Células Madre Mesenquimatosas/citología , Ingeniería de Tejidos/métodos , Proteína Morfogenética Ósea 2 , Proteínas Morfogenéticas Óseas/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Citocinas/metabolismo , Humanos , Proteína 2 Inhibidora de la Diferenciación/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Interleucina-11/metabolismo , Modelos Biológicos , Osteogénesis , Proteínas Proto-Oncogénicas c-fos/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo
7.
PLoS One ; 16(8): e0255382, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34379648

RESUMEN

To achieve herd immunity against COVID-19, it is crucial to know the drivers of vaccination intention and, thereby, vaccination. As the determinants of vaccination differ across vaccines, target groups and contexts, we investigate COVID-19 vaccination intention using data from university students from three countries, the Netherlands, Belgium and Portugal. We investigate the psychological drivers of vaccination intention using the 5C model as mediator. This model includes five antecedents of vaccination: Confidence, Complacency, Constraints, Calculation and Collective Responsibility. First, we show that the majority of students have a positive propensity toward getting vaccinated against COVID-19, though only 41% of students are completely acceptant. Second, using the 5C model, we show that 'Confidence' (ß = 0.33, SE = 03, p < .001) and 'Collective Responsibility' (ß = 0.35, SE = 04, p < .001) are most strongly related to students' COVID-19 vaccination intention. Using mediation analyses, we show that the perceived risk and effectiveness of the vaccine as well as trust in the government and health authorities indirectly relate to vaccination intention through 'Confidence'. The perceived risk of COVID-19 for one's social circle and altruism, the need to belong and psychopathy traits indirectly relate to vaccination intention through 'Collective Responsibility'. Hence, targeting the psychological characteristics associated with 'Confidence' and 'Collective Responsibility' can improve the effectiveness of vaccination campaigns among students.


Asunto(s)
COVID-19/prevención & control , Modelos Teóricos , Estudiantes/psicología , Vacunación/psicología , Altruismo , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/inmunología , Humanos , Riesgo , SARS-CoV-2/aislamiento & purificación , Autoeficacia , Encuestas y Cuestionarios
8.
PLoS One ; 16(11): e0259922, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34752485

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0255382.].

9.
ACS Nano ; 15(10): 16501-16514, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34585583

RESUMEN

Recently, there has been significant interest in using dielectric nanocavities for the controlled scattering of light, owing to the diverse electromagnetic modes that they support. For plasmonic systems, electron energy-loss spectroscopy (EELS) is now an established method enabling structure-optical property analysis at the scale of the nanostructure. Here, we instead test its potential for the near-field mapping of photonic eigenmodes supported in planar dielectric nanocavities, which are lithographically patterned from amorphous silicon according to standard photonic principles. By correlating results with finite element simulations, we demonstrate how many of the EELS excitations can be directly corresponded to various optical eigenmodes of interest for photonic engineering. The EELS maps present a high spatial definition, displaying intensity features that correlate precisely to the impact parameters giving the highest probability of modal excitation. Further, eigenmode characteristics translate into their EELS signatures, such as the spatially and energetically extended signal of the low Q-factor electric dipole and nodal intensity patterns emerging from excitation of toroidal and second-order magnetic modes within the nanocavity volumes. Overall, the spatial-spectral nature of the data, combined with our experimental-simulation toolbox, enables interpretation of subtle changes in the EELS response across a range of nanocavity dimensions and forms, with certain simulated resonances matching the excitation energies within ±0.01 eV. By connecting results to far-field simulations, perspectives are offered for tailoring the nanophotonic resonances via manipulating nanocavity size and shape.

10.
J Neurol ; 266(8): 2092, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31240447

RESUMEN

The original version of this article unfortunately contained a mistake in the acknowledgement section.

11.
J Neurol ; 265(4): 880-884, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29427025

RESUMEN

OBJECTIVE: While telemedicine is in expanding use in acute stroke care, little is known about its use in general neurology, especially in acute care. We sought to investigate the feasibility and possible effects of a telemedicine device within the neurological back-up service of an acute care hospital. METHODS: In a 450 bed academic teaching hospital an experienced neurologist (EN) is on call to support the junior doctor at the hospital. Support was possible whether by standard telephone advice (TA) or by audiovisual consultations (AVC). In AVC the expert used a mobile telemedicine device and so he could establish audiovisual contact from his home to the emergency room and examine newly admitted patients. Technical and patient details including timing and diagnosis were recorded. Video and audio quality as well as impact of AVC on diagnosis was rated by the EN. RESULTS: Out of about 1200 cases in off peak times, during the study period, 164 AVC including remote video examination were done (13.6%). Also 48 cases were documented by pure TA. Video quality was rated to a medium of 1.7, audio quality to 2.1. In 36 cases the audiovisual consultation was influenced by technical issues leading to cessation of AVC in 8 cases. Duration of teleconsultation was 17.3 min in AVC compared to 8.7 min for TA. The consultation diagnosis in AVC was confirmed in 74.4% of all cases compared to 57.7% in TA. AVC was rated as a valuable contribution to the diagnostic workup in 74.3% of all cases seen. In about 40% of all cases AVC was not possible due to technical or organizational reasons. CONCLUSIONS: Audiovisual consultation seems to be a feasible and useful support in routine neurology back-up service of an acute care hospital. Better mobility of devices and flexibility of service is needed to improve availability and quality of this valuable tool.


Asunto(s)
Neurología/métodos , Consulta Remota/métodos , Accidente Cerebrovascular/terapia , Telemedicina/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hospitales de Enseñanza , Humanos , Masculino , Persona de Mediana Edad , Neurólogos , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico , Telemedicina/estadística & datos numéricos , Adulto Joven
12.
FEBS J ; 274(24): 6329-39, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18028427

RESUMEN

cDNA for octopine dehydrogenase (ODH) from the adductor muscle of the great scallop, Pecten maximus, was cloned using 5'- and 3'-RACE. The cDNA comprises an ORF of 1197 nucleotides and the deduced amino acid sequence encodes a protein of 399 amino acids. ODH was heterologously expressed in Escherichia coli with a C-terminal penta His-tag. ODH-5His was purified to homogeneity using metal-chelate affinity chromatography and Sephadex G-100 gel filtration. Recombinant ODH had kinetic properties similar to those of wild-type ODH isolated from the scallop's adductor muscle. Site-directed mutagenesis was used to elucidate the involvement of several amino acid residues for the reaction catalyzed by ODH. Cys148, which is conserved in all opine dehydrogenases known to date, was converted to serine or alanine, showing that this residue is not intrinsically important for catalysis. His212, Arg324 and Asp329, which are also conserved in all known opine dehydrogenase sequences, were subjected to site-directed mutagenesis. Modification of these residues revealed their importance for the catalytic activity of the enzyme. Conversion of each of these residues to alanine resulted in strong increases in K(m) and decreases in k(cat) values for pyruvate and L-arginine, but had little effect on the K(m) and k(cat) values for NADH. Assuming a similar structure for ODH compared with the only available structure of a bacterial opine dehydrogenase, these three amino acids may function as a catalytic triad in ODH similar to that found in lactate dehydrogenase or malate dehydrogenase. The carboxyl group of pyruvate is then stabilized by Arg324. In addition to orienting the substrate, His212 will act as an acid-base catalyst by donating a proton to the carbonyl group of pyruvate. The acidity of this histidine is further increased by the proximity of Asp329.


Asunto(s)
Aminoácido Oxidorreductasas/metabolismo , Pecten/enzimología , Proteínas Recombinantes/metabolismo , Aminoácido Oxidorreductasas/genética , Animales , Arginina/química , Arginina/metabolismo , Western Blotting , Dominio Catalítico/genética , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Cinética , Datos de Secuencia Molecular , Estructura Molecular , Mutación , NAD/química , NAD/metabolismo , Pecten/genética , Piruvatos/química , Piruvatos/metabolismo , Análisis de Secuencia de ADN , Especificidad por Sustrato
13.
Biomaterials ; 27(3): 315-23, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16125223

RESUMEN

In an effort to produce clinically relevant volumes of tissue-engineered bone products, we report a direct perfusion bioreactor system. Goat bone marrow stromal cells (GBMSCs) were dynamically seeded and proliferated in this system in relevant volumes (10 cc) of small sized macroporous biphasic calcium phosphate scaffolds (BCP, 2-6 mm). Cell load and cell distribution were shown using methylene blue block staining and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) staining was used to demonstrate viability of the present cells. After 19 days of cultivation, the scaffolds were covered with a viable, homogeneous cell layer. The hybrid structures became interconnected and a dense layer of extracellular matrix was present as visualized by environmental scanning electron microscopy (ESEM). ESEM images showed within the extracellular matrix sphere like structures which were identified as calcium phosphate nodules by energy dispersive X-ray analysis (EDX). On line oxygen measurements during cultivation were correlated with proliferating GBMSCs. It was shown that the oxygen consumption can be used to estimate GBMSC population doubling times during growth in this bioreactor system. Implantation of hybrid constructs, which were proliferated dynamically, showed bone formation in nude mice after 6 weeks of implantation. On the basis of our results we conclude that a direct perfusion bioreactor system is capable of producing clinically relevant volumes of tissue-engineered bone in a bioreactor system which can be monitored on line during cultivation and show bone formation after implantation in nude mice.


Asunto(s)
Reactores Biológicos , Trasplante Óseo/métodos , Huesos/citología , Osteogénesis , Ingeniería de Tejidos/métodos , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/ultraestructura , Fosfatos de Calcio/síntesis química , Fosfatos de Calcio/química , Técnicas de Cultivo de Célula/métodos , Proliferación Celular , Células Cultivadas , Microanálisis por Sonda Electrónica , Cabras , Hidroxiapatitas/síntesis química , Hidroxiapatitas/química , Ratones , Ratones Desnudos , Microscopía Electrónica de Rastreo , Osteoblastos/citología , Osteoblastos/metabolismo , Osteocitos/citología , Osteocitos/metabolismo , Oxígeno/metabolismo , Células del Estroma/citología , Células del Estroma/ultraestructura
14.
JMM Case Rep ; 3(3): e005043, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28348762

RESUMEN

INTRODUCTION: Ignatzschineria species were previously known as Schineria species and are well known inhabitants of the larvae of the parasitic fly Wohlfahrtia magnifica. CASE PRESENTATION: We report a case of Ignatzschineria species bacteraemia in a Dutch patient with a wound infested with maggots. CONCLUSION: In the past, these bacteria have been isolated from Wohlfahrtia magnifica, a fly not indigenous to The Netherlands. Other fly larvae such as the blowfly larvae probably infested the wound and harboured this Ignatzschineria strain which subsequently caused this bacteraemia. A two-week course of amoxicillin/clavulanic acid was given with good clinical response.

15.
Neurosci Lett ; 356(2): 87-90, 2004 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-14746870

RESUMEN

In complex regional pain syndrome (CRPS) many clinical symptoms suggest involvement of the central nervous system. Neuropathic pain as the leading symptom is often resistant to therapy. In the present study we investigated the analgesic efficiency of repetitive transcranial magnetic simulation (rTMS) applied to the motor cortex contralateral to the CRPS-affected side. Seven out of ten patients reported decreased pain intensities. Pain relief occurred 30 s after stimulation, whereas the maximum effect was found 15 min later. Pain re-intensified increasingly 45 min after rTMS. In contrast, sham rTMS did not alter pain perception. These findings provide evidence that in CRPS I pain perception can be modulated by repetitive motor cortex stimulation.


Asunto(s)
Terapia por Estimulación Eléctrica , Corteza Motora/fisiología , Manejo del Dolor , Distrofia Simpática Refleja/terapia , Estimulación Magnética Transcraneal , Adulto , Anciano , Terapia por Estimulación Eléctrica/métodos , Femenino , Lateralidad Funcional , Humanos , Masculino , Persona de Mediana Edad , Dolor/fisiopatología , Dimensión del Dolor , Percepción/fisiología , Factores de Tiempo , Resultado del Tratamiento
16.
Mar Biotechnol (NY) ; 6(5): 493-502, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15565272

RESUMEN

The complete complementary DNA sequences of genes presumably coding for opine dehydrogenases from Arabella iricolor (sandworm), Haliotis discus hannai (abalone), and Patinopecten yessoensis (scallop) were determined, and partial cDNA sequences were derived for Meretrix lusoria (Japanese hard clam) and Spisula sachalinensis (Sakhalin surf clam). The primers ODH-9F and ODH-11R proved useful for amplifying the sequences for opine dehydrogenases from the 4 mollusk species investigated in this study. The sequence of the sandworm was obtained using primers constructed from the amino acid sequence of tauropine dehydrogenase, the main opine dehydrogenase in A. iricolor. The complete cDNA sequence of A. iricolor, H. discus hannai, and P. yessoensis encode 397, 400, and 405 amino acids, respectively. All sequences were aligned and compared with published databank sequences of Loligo opalescens, Loligo vulgaris (squid), Sepia officinalis (cuttlefish), and Pecten maximus (scallop). As expected, a high level of homology was observed for the cDNA from closely related species, such as for cephalopods or scallops, whereas cDNA from the other species showed lower-level homologies. A similar trend was observed when the deduced amino acid sequences were compared. Furthermore, alignment of these sequences revealed some structural motifs that are possibly related to the binding sites of the substrates. The phylogenetic trees derived from the nucleotide and amino acid sequences were consistent with the classification of species resulting from classical taxonomic analyses.


Asunto(s)
Evolución Molecular , Moluscos/genética , Oxidorreductasas/genética , Poliquetos/genética , Aminoácido Oxidorreductasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Análisis por Conglomerados , Cartilla de ADN , ADN Complementario/genética , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia
17.
MMW Fortschr Med ; 161(Suppl 3): 44-52, 2019 11.
Artículo en Alemán | MEDLINE | ID: mdl-31713788
19.
ACS Nano ; 6(11): 9711-7, 2012 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-23020274

RESUMEN

We report on the experimental and the theoretical investigation of multipole surface plasmon resonances in metal nanowires conductively connected by small junctions. The influence of a conductive junction on the resonance energies of nanowire dimers was simulated using the finite element method based software CST Microwave Studio and experimentally measured by electron energy-loss spectroscopy in a transmission electron microscope. We extend the analysis of conductively connected structures to higher order multipole modes up to third order, including dark modes. Our results reveal that an increase in junction size does not shift significantly the antibonding modes, but causes a strong blue shift of the bonding modes, leading to an energetic rearrangement of the modes compared to those of a capacitively coupled dimer with similar dimensions.


Asunto(s)
Nanopartículas del Metal/química , Modelos Químicos , Resonancia por Plasmón de Superficie/métodos , Simulación por Computador , Dimerización , Conductividad Eléctrica , Luz , Nanopartículas del Metal/ultraestructura , Dispersión de Radiación
20.
Tissue Eng Part C Methods ; 16(3): 479-85, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19686060

RESUMEN

Survival and growth of cellular grafts in tissue engineering (TE) are limited by the rate of oxygen (O(2)) and nutrient diffusion. As such, monitoring the levels of nutrients and O(2) available to the cells is essential to assess the physiology of the cells and to evaluate strategies aiming at improving nutrient availability. In this article, a reporter system containing the luciferase gene driven by a hypoxia responsive promoter was used to monitor cellular hypoxia in a TE context. We report that luciferase activity correlates with the O(2) tension in the cell culture medium. When transgenic cells were seeded onto scaffolds and implanted in immune-deficient mice subcutaneously, luciferase activity was detected. To validate the response to O(2) levels of this reporter system, we cultured transgenic cells on biomaterials in a flow perfusion bioreactor and observed that cells in the bioreactor displayed a drastically lower luciferase activity than conventional static culture, and that higher luciferase activity is observed in the interior of a tissue-engineered construct, illustrating the uneven O(2) distribution in three-dimensional constructs under conventional static culture. We conclude that this reporter system is a versatile tool to investigate cellular O(2) availability in TE both in vitro and in vivo.


Asunto(s)
Hipoxia , Ingeniería de Tejidos , Animales , Animales Modificados Genéticamente , Reactores Biológicos , Células CHO , Cricetinae , Cricetulus , Medios de Cultivo , Humanos , Luciferasas/genética
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