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1.
Cogn Emot ; 30(4): 745-61, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-25864486

RESUMEN

This study examined interrelations of trait and state empathy in an adolescent sample. Self-reported affective trait empathy and cognitive trait empathy were assessed during a home visit. During a test session at the university, motor empathy (facial electromyography), and self-reported affective and cognitive state empathy were assessed in response to empathy-inducing film clips portraying happiness and sadness. Adolescents who responded with stronger motor empathy consistently reported higher affective state empathy. Adolescents' motor empathy was also positively related to cognitive state empathy, either directly or indirectly via affective state empathy. Whereas trait empathy was consistently, but modestly, related to state empathy with sadness, for state empathy with happiness few trait-state associations were found. Together, the findings provide support for the notion that empathy is a multi-faceted phenomenon. Motor, affective and cognitive empathy seem to be related processes, each playing a different role in the ability to understand and share others' feelings.


Asunto(s)
Conducta del Adolescente/psicología , Afecto/fisiología , Cognición/fisiología , Empatía/fisiología , Cara/fisiología , Adolescente , Electromiografía , Femenino , Humanos , Masculino , Autoinforme , Adulto Joven
2.
J Nerv Ment Dis ; 202(10): 732-7, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25186662

RESUMEN

The aim of this study was to examine early cognitive performance after a delirium in elderly general hospital patients. Patients were divided into a delirium (n = 47) and a control (n = 25) group. One week before discharge and after delirium had cleared in the first group, all patients completed a neuropsychological test battery (The Cambridge Cognitive Examination-Revised [CAMCOG-R]). Group differences in cognitive performance were analyzed adjusting for differences in baseline sociodemographic and clinical variables. Adjusting for group differences in baseline variables, the delirium group performed significantly worse than the control group on CAMCOG-R; its subdomains language, praxis, and executive functioning; and on Mini Mental State Examination derived from CAMCOG-R. The occurrence of delirium in hospital thus detrimentally affects early cognitive performance.


Asunto(s)
Trastornos del Conocimiento/etiología , Delirio/complicaciones , Función Ejecutiva/fisiología , Anciano , Anciano de 80 o más Años , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/fisiopatología , Comorbilidad , Estudios Transversales , Delirio/diagnóstico , Delirio/epidemiología , Demencia/epidemiología , Diabetes Mellitus/epidemiología , Femenino , Evaluación Geriátrica , Hospitalización , Humanos , Masculino , Pruebas Neuropsicológicas , Recuperación de la Función/fisiología , Factores de Tiempo
3.
Biol Psychol ; 185: 108737, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38134999

RESUMEN

In behavioral studies, facial electromyographic (EMG) responses to external stimuli or internal events are usually quantified relative to the resting state, presumed to represent a neutral baseline condition. In the large majority of recent studies, EMG responses were expressed as a difference score in terms of microvolts with the resting state. We argue that since EMG activity is measured on a ratio scale rather than on an interval scale, percentage scores should be used instead of difference scores. Reanalyzing results from an earlier study on the relationships between facial EMG responses and affective empathic responses to emotional video clips, we found that the two different types of EMG response quantification were differently related to affective empathy. Relationships between EMG responses and affective empathy were more consistent or stronger for percentage scores than for difference scores. In another study, facial EMG mimicry responses to pictures of emotional facial expressions were stronger for percentage scores than for difference scores. The adequacy of percentage scores relative to difference scores as indices of psychological variables may be simply checked by comparing both types of scores.


Asunto(s)
Emociones , Músculos Faciales , Humanos , Músculos Faciales/fisiología , Electromiografía/métodos , Emociones/fisiología , Empatía , Expresión Facial , Estándares de Referencia
4.
J Psychiatr Res ; 176: 422-429, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38959825

RESUMEN

Facial mimicry serves as an evolutionarily rooted important interpersonal communication process that touches on the concepts of socialization and empathy. Facial electromyography (EMG) of the corrugator muscle and the zygomaticus muscle was recorded while male forensic psychopathic patients and controls watched morphed angry or happy facial expressions. We tested the hypothesis that psychopathic patients would show weaker short latency facial mimicry (that is, within 600 ms after stimulus onset) than controls. Exclusively in the group of 20 psychopathic patients, we tested in a placebo-controlled crossover within-subject design the hypothesis that oxytocin would enhance short-latency facial mimicry. Compared with placebo, we found no oxytocin-related significant short-latency responses of the corrugator and the zygomaticus. However, compared with 19 normal controls, psychopathic patients in the placebo condition showed significantly weaker short-latency zygomaticus responses to happy faces, while there was a trend toward significantly weaker short-latency corrugator responses to angry faces. These results are consistent with a recent study of facial EMG responses in adolescents with psychopathic traits. We therefore posit a lifetime developmental deficit in psychopathy pertaining short-latency mimicry of emotional facial expressions. Ultimately, this deficit in mimicking angry and happy expressions may hinder the elicitation of empathy, which is known to be impaired in psychopathy.


Asunto(s)
Trastorno de Personalidad Antisocial , Electromiografía , Expresión Facial , Músculos Faciales , Oxitocina , Humanos , Masculino , Oxitocina/administración & dosificación , Oxitocina/farmacología , Adulto , Trastorno de Personalidad Antisocial/fisiopatología , Músculos Faciales/efectos de los fármacos , Músculos Faciales/fisiología , Músculos Faciales/fisiopatología , Adulto Joven , Emociones/fisiología , Emociones/efectos de los fármacos , Estudios Cruzados , Conducta Imitativa/fisiología , Estimulación Luminosa , Reconocimiento Facial/fisiología , Reconocimiento Facial/efectos de los fármacos , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/fisiología
5.
Appl Environ Microbiol ; 78(9): 3145-55, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22344641

RESUMEN

Aspergillus niger is an important organism for the production of industrial enzymes such as hemicellulases and pectinases. The xylan-backbone monomer, d-xylose, is an inducing substance for the coordinate expression of a large number of polysaccharide-degrading enzymes. In this study, the responses of 22 genes to low (1 mM) and high (50 mM) d-xylose concentrations were investigated. These 22 genes encode enzymes that function as xylan backbone-degrading enzymes, accessory enzymes, cellulose-degrading enzymes, or enzymes involved in the pentose catabolic pathway in A. niger. Notably, genes encoding enzymes that have a similar function (e.g., xylan backbone degradation) respond in a similar manner to different concentrations of d-xylose. Although low d-xylose concentrations provoke the greatest change in transcript levels, in particular, for hemicellulase-encoding genes, transcript formation in the presence of high concentrations of d-xylose was also observed. Interestingly, a high d-xylose concentration is favorable for certain groups of genes. Furthermore, the repressing influence of CreA on the transcription and transcript levels of a subset of these genes was observed regardless of whether a low or high concentration of d-xylose was used. Interestingly, the decrease in transcript levels of certain genes on high d-xylose concentrations is not reflected by the transcript level of their activator, XlnR. Regardless of the d-xylose concentration applied and whether CreA was functional, xlnR was constitutively expressed at a low level.


Asunto(s)
Aspergillus niger/enzimología , Aspergillus niger/metabolismo , Proteínas Fúngicas/metabolismo , Regulación Enzimológica de la Expresión Génica , Hidrolasas/metabolismo , Proteínas Represoras/metabolismo , Transactivadores/metabolismo , Xilosa/metabolismo , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica
6.
Psychophysiology ; 59(1): e13945, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34553782

RESUMEN

Using still pictures of emotional facial expressions as experimental stimuli, reduced amygdala responses or impaired recognition of basic emotions were repeatedly found in people with psychopathic traits. The amygdala also plays an important role in short-latency facial mimicry responses. Since dynamic emotional facial expressions may have higher ecological validity than still pictures, we compared short-latency facial mimicry responses to dynamic and static emotional expressions between adolescents with psychopathic traits and normal controls. Facial EMG responses to videos or still pictures of emotional expressions (happiness, anger, sadness, fear) were measured. Responses to 500-ms dynamic expressions in videos, as well as the subsequent 1500-ms phase of maximal (i.e., static) expression, were compared between male adolescents with disruptive behavior disorders and high (n = 14) or low (n = 17) callous-unemotional (CU) traits, and normal control subjects (n = 32). Responses to still pictures were also compared between groups. EMG responses to dynamic expressions were generally significantly smaller in the high-CU group than in the other two groups, which generally did not differ. These group differences gradually emerged during the 500-ms stimulus presentation period but in general they were already seen a few hundred milliseconds after stimulus onset. Group differences were absent during the 1500-ms phase of maximal expression and during exposure to still pictures. Subnormal short-latency mimicry responses to dynamic emotional facial expressions in the high-CU group might have negative consequences for understanding emotional facial expressions of others during daily life when human facial interactions are primarily dynamic.


Asunto(s)
Déficit de la Atención y Trastornos de Conducta Disruptiva , Expresión Facial , Reconocimiento Facial/fisiología , Reconocimiento en Psicología/fisiología , Adolescente , Emociones/fisiología , Humanos , Masculino , Tiempo de Reacción
7.
ChemistryOpen ; 11(10): e202200029, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35233991

RESUMEN

Oxidised starch is currently produced from native starch using sodium hypochlorite as an oxidising agent. The use of hypochlorite has undesired side reactions and produces stoichiometric amounts of waste (salt), thus alternative oxidation methods are desired. In this study, the potential of two catalysed starch oxidation methods to reduce the environmental impact (EI) of oxidised starch production are assessed. We compared the EI of oxidation with molecular oxygen (heterogeneously catalysed) and hydrogen peroxide (homogeneously catalysed) to hypochlorite oxidation through life cycle assessment (LCA). The results confirm that hypochlorite oxidation is the main environmental hotspot in the current process of oxidised starch production, and that both hydroperoxide oxidation and molecular oxygen oxidation can significantly lower the EI of the process. The impact reduction is most significant in the categories of freshwater eutrophication (∼67 %), ozone depletion (∼66 %), climate change (35-60 %) and resource use (40 %-78 %) for peroxide and molecular oxygen oxidation, respectively.


Asunto(s)
Peróxido de Hidrógeno , Almidón , Ambiente , Ácido Hipocloroso , Oxígeno , Hipoclorito de Sodio
8.
Bioprocess Biosyst Eng ; 32(3): 289-99, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18668267

RESUMEN

This study considers two aspects of the implementation of a biomass growth observer and specific growth rate controller in scale-up from small- to pilot-scale bioreactors towards a feasible bulk production process for whole-cell vaccine against whooping cough. The first is the calculation of the oxygen uptake rate, the starting point for online monitoring and control of biomass growth, taking into account the dynamics in the gas-phase. Mixing effects and delays are caused by amongst others the headspace and tubing to the analyzer. These gas phase dynamics are modelled using knowledge of the system in order to reconstruct oxygen consumption. The second aspect is to evaluate performance of the monitoring and control system with the required modifications of the oxygen consumption calculation on pilot-scale. In pilot-scale fed-batch cultivation good monitoring and control performance is obtained enabling a doubled concentration of bulk vaccine compared to standard batch production.


Asunto(s)
Reactores Biológicos/microbiología , Bordetella pertussis/fisiología , Técnicas de Cultivo de Célula/métodos , Modelos Biológicos , Oxígeno/metabolismo , Vacuna contra la Tos Ferina/biosíntesis , Tos Ferina/prevención & control , Algoritmos , Bordetella pertussis/citología , Proliferación Celular , Simulación por Computador , Retroalimentación/fisiología , Humanos , Vacuna contra la Tos Ferina/aislamiento & purificación
9.
Front Psychol ; 10: 318, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30858810

RESUMEN

Facial electromyography research shows that corrugator supercilii ("frowning muscle") activity tracks the emotional valence of linguistic stimuli. Grounded or embodied accounts of language processing take such activity to reflect the simulation or "re-enactment" of emotion, as part of the retrieval of word meaning (e.g., of "furious") and/or of building a situation model (e.g., for "Mark is furious"). However, the same muscle also expresses our primary emotional evaluation of things we encounter. Language-driven affective simulation can easily be at odds with the reader's affective evaluation of what language describes (e.g., when we like Mark being furious). In a previous experiment ('t Hart et al., 2018) we demonstrated that neither language-driven simulation nor affective evaluation alone seem sufficient to explain the corrugator patterns that emerge during online language comprehension in these complex cases. Those results showed support for a multiple-drivers account of corrugator activity, where both simulation and evaluation processes contribute to the activation patterns observed in the corrugator. The study at hand replicates and extends these findings. With more refined control over when precisely affective information became available in a narrative, we again find results that speak against an interpretation of corrugator activity in terms of simulation or evaluation alone, and as such support the multiple-drivers account. Additional evidence suggests that the simulation driver involved reflects simulation at the level of situation model construction, rather than at the level of retrieving concepts from long-term memory. In all, by giving insights into how language-driven simulation meshes with the reader's evaluative responses during an unfolding narrative, this study contributes to the understanding of affective language comprehension.

10.
Front Psychol ; 9: 613, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29760671

RESUMEN

Facial electromyography research shows that corrugator supercilii ("frowning muscle") activity tracks the emotional valence of linguistic stimuli. Grounded or embodied accounts of language processing take such activity to reflect the simulation or "reenactment" of emotion, as part of the retrieval of word meaning (e.g., of "furious") and/or of building a situation model (e.g., for "Mark is furious"). However, the same muscle also expresses our primary emotional evaluation of things we encounter. Language-driven affective simulation can easily be at odds with the reader's affective evaluation of what language describes (e.g., when we like Mark being furious). To examine what happens in such cases, we independently manipulated simulation valence and moral evaluative valence in short narratives. Participants first read about characters behaving in a morally laudable or objectionable fashion: this immediately led to corrugator activity reflecting positive or negative affect. Next, and critically, a positive or negative event befell these same characters. Here, the corrugator response did not track the valence of the event, but reflected both simulation and moral evaluation. This highlights the importance of unpacking coarse notions of affective meaning in language processing research into components that reflect simulation and evaluation. Our results also call for a re-evaluation of the interpretation of corrugator EMG, as well as other affect-related facial muscles and other peripheral physiological measures, as unequivocal indicators of simulation. Research should explore how such measures behave in richer and more ecologically valid language processing, such as narrative; refining our understanding of simulation within a framework of grounded language comprehension.

11.
J Psychiatr Res ; 40(2): 112-21, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16176819

RESUMEN

Based on the assumption that facial mimicry is a key factor in emotional empathy, and clinical observations that children with disruptive behavior disorders (DBD) are weak empathizers, the present study explored whether DBD boys are less facially responsive to facial expressions of emotions than normal controls. Facial electromyographic (EMG) activity in the zygomaticus major and corrugator supercilii muscle regions, and heart rate activity were studied in 22 clinically referred 8-12-year-old DBD boys and 22 age-matched normal controls during exposure to dynamic happy and angry expressions. Dispositional emotional empathy was assessed by a self-report questionnaire for children. The happy and angry facial expressions evoked distinct facial EMG response patterns, with increased zygomaticus muscle activity to happy expressions and increased corrugator muscle activity to angry expressions. The corrugator (but not the zygomaticus) muscle response pattern was less pronounced for DBD boys than the normal controls. Attending to the emotional expressions was associated with equivalent cardiac deceleration in both groups, reflecting a similar orienting/attention response. Lower empathy scores were obtained for DBD boys than for normal controls. In conclusion, facial mimicry responses to angry facial expressions were subnormal in DBD boys, which may be a sign of a deficient early component in the process of emotional empathy, and thus play a role in impaired empathic responding.


Asunto(s)
Afecto , Déficit de la Atención y Trastornos de Conducta Disruptiva/psicología , Expresión Facial , Músculos Faciales/inervación , Conducta Imitativa , Niño , Electromiografía , Empatía , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Encuestas y Cuestionarios
12.
J Abnorm Child Psychol ; 44(2): 269-81, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25711459

RESUMEN

This 2-wave longitudinal study aimed (1) to investigate whether high resting RSA predicted adolescents' lower externalizing behavior and higher empathic concern, and (2) to address the potential moderating role of resting RSA in the association between parent-adolescent relationship quality and adolescents' externalizing behavior and empathic concern. In a sample of 379 adolescents (212 boys, 167 girls), resting RSA was assessed during a laboratory session, and adolescents reported on parental support, negative interaction with parents, empathic concern and externalizing behavior during a home visit. We found no support for high resting RSA predicting low externalizing behavior or high empathic concern. However, in line with our hypotheses, we did find several instances of RSA functioning as a moderator, although the interaction patterns varied. First, negative interaction with parents was a negative predictor of externalizing behavior for girls low in resting RSA, whereas the association was non-significant for girls with high RSA. Second, higher negative interaction with parents predicted lower empathic concern for boys high in resting RSA, whereas the association was reversed for boys with low resting RSA. Third, parental support was a positive predictor of empathic concern for girls high in resting RSA, whereas the association was non-significant for girls low in resting RSA. The findings suggest that adolescents with different levels of resting RSA respond differentially to relationship quality with parents.


Asunto(s)
Conducta del Adolescente/fisiología , Empatía/fisiología , Relaciones Padres-Hijo , Arritmia Sinusal Respiratoria/fisiología , Ajuste Social , Apoyo Social , Adolescente , Femenino , Humanos , Estudios Longitudinales , Masculino , Factores Sexuales
13.
BMC Syst Biol ; 10: 13, 2016 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-26822482

RESUMEN

BACKGROUND: Transcription of genes coding for xylanolytic and cellulolytic enzymes in Aspergillus niger is controlled by the transactivator XlnR. In this work we analyse and model the transcription dynamics in the XlnR regulon from time-course data of the messenger RNA levels for some XlnR target genes, obtained by reverse transcription quantitative PCR (RT-qPCR). Induction of transcription was achieved using low (1 mM) and high (50 mM) concentrations of D-xylose (Xyl). We investigated the wild type strain (Wt) and a mutant strain with partial loss-of-function of the carbon catabolite repressor CreA (Mt). RESULTS: An improved kinetic differential equation model based on two antagonistic Hill functions was proposed, and fitted to the time-course RT-qPCR data from the Wt and the Mt by numerical optimization of the parameters. We show that perturbing the XlnR regulon with Xyl in low and high concentrations results in different expression levels and transcription dynamics of the target genes. At least four distinct transcription profiles were observed, particularly for the usage of 50 mM Xyl. Higher transcript levels were observed for some genes after induction with 1 mM rather than 50 mM Xyl, especially in the Mt. Grouping the expression profiles of the investigated genes has improved our understanding of induction by Xyl and the according regulatory role of CreA. CONCLUSIONS: The model explains for the higher expression levels at 1 mM versus 50 mM in both Wt and Mt. It does not yet fully encapsulate the effect of partial loss-of-function of CreA in the Mt. The model describes the dynamics in most of the data and elucidates the time-dynamics of the two major regulatory mechanisms: i) the activation by XlnR, and ii) the carbon catabolite repression by CreA.


Asunto(s)
Aspergillus niger/genética , Modelos Genéticos , Regulón/genética , Transcripción Genética , Aspergillus niger/metabolismo , Retroalimentación Fisiológica , Proteínas Fúngicas/metabolismo
14.
Biotechnol Biofuels ; 9: 63, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26981155

RESUMEN

BACKGROUND: Despite the recognition that feedstock composition influences biomass conversion efficiency, limited information exists as to how bioenergy crops with reduced recalcitrance can improve the economics and sustainability of cellulosic fuel conversion platforms. We have compared the bioenergy potential-estimated as total glucose productivity per hectare (TGP)-of maize cultivars contrasting for cell wall digestibility across processing conditions of increasing thermochemical severity. In addition, exploratory environmental impact and economic modeling were used to assess whether the development of bioenergy feedstocks with improved cell wall digestibility can enhance the environmental performance and reduce the costs of biomass pretreatment and enzymatic conversion. RESULTS: Systematic genetic gains in cell wall degradability can lead to significant advances in the productivity (TGP) of cellulosic fuel biorefineries under low severity processing; only if gains in digestibility are not accompanied by substantial yield penalties. For a hypothetical maize genotype combining the best characteristics available in the evaluated cultivar panel, TGP under mild processing conditions (~3.7 t ha(-1)) matched the highest realizable yields possible at the highest processing severity. Under this scenario, both, the environmental impacts and processing costs for the pretreatment and enzymatic saccharification of maize stover were reduced by 15 %, given lower chemical and heat consumption. CONCLUSIONS: Genetic improvements in cell wall composition leading to superior cell wall digestibility can be advantageous for cellulosic fuel production, especially if "less severe" processing regimes are favored for further development. Exploratory results indicate potential cost and environmental impact reductions for the pretreatment and enzymatic saccharification of maize feedstocks exhibiting higher cell wall degradability. Conceptually, these results demonstrate that the advance of bioenergy cultivars with improved biomass degradability can enhance the performance of currently available biomass-to-ethanol conversion systems.

15.
J Vasc Access ; 16(4): 327-32, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25768047

RESUMEN

PURPOSE: In order to find the correct final position of the tip of a central venous catheter, we have developed a new electric method (the Proximity of Cardiac Motion (PCM) method), designed to work in tandem with the existing ECG-based method. METHODS: A small, patient-safe, high-frequency current is fed through the catheter (via the saline-filled lumen of the catheter, or a stylet). Simultaneously, the resulting voltage is measured by two electrodes on the frontal thoracic skin. The catheter tip hence functions as a current source inside the vasculature. The cardiac motion produces a variation in the amplitude of the measured voltage in the rhythm of the cardiac cycle, and the strength of this oscillatory variation is proportional to the strength of the incident current field on the heart, which is a rapidly decaying function of the distance between the catheter tip and the cavoatrial junction (CAJ). Hence the strength of this oscillatory variation is a strong indicator for the proximity of the catheter tip with respect to the CAJ. RESULTS: The new method has been tested in an animal model, yielding an average final position of the catheter tip of 2.1 cm above the CAJ, with a maximum deviation of 0.5 cm. CONCLUSIONS: We conclude that the new PCM method can be combined with the existing ECG method, and may potentially have significant added value when the ECG method cannot be applied, for example, in patients with atrial fibrillation or a pacemaker.


Asunto(s)
Cardiografía de Impedancia/instrumentación , Cardiografía de Impedancia/métodos , Cateterismo Venoso Central/instrumentación , Cateterismo Venoso Central/métodos , Catéteres Venosos Centrales , Animales , Volumen Sanguíneo , Equipos y Suministros Eléctricos , Electricidad , Electrocardiografía , Diseño de Equipo , Estudios de Factibilidad , Modelos Animales , Valor Predictivo de las Pruebas , Procesamiento de Señales Asistido por Computador , Porcinos
16.
Data Brief ; 5: 84-94, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26484359

RESUMEN

This data article contains seven figures and two tables supporting the research article entitled: spatiotemporal proliferation of human stromal cells adjusts to nutrient availability and leads to stanniocalcin-1 expression in vitro and in vivo[1]. The data explain the culture of stromal cells in vitro in three culture systems: discs, scaffolds and scaffolds in a perfusion bioreactor system. Also, quantification of extracellular matrix components (ECM) in vitro and staining of ECM components in vivo can be found here. Finally the quantification of blood vessels dimensions from CD31 signals and representative histograms of stanniocalcin-1 fluorescent signals in negative controls and experimental conditions in vivo are presented.

17.
Biomaterials ; 61: 190-202, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26004234

RESUMEN

Cells and tissues are intrinsically adapted to molecular gradients and use them to maintain or change their activity. The effect of such gradients is particularly important for cell populations that have an intrinsic capacity to differentiate into multiple cell lineages, such as bone marrow derived mesenchymal stromal cells (MSCs). Our results showed that nutrient gradients prompt the spatiotemporal organization of MSCs in 3D culture. Cells adapted to their 3D environment without significant cell death or cell differentiation. Kinetics data and whole-genome gene expression analysis suggest that a low proliferation activity phenotype predominates in stromal cells cultured in 3D, likely due to increasing nutrient limitation. These differences implied that despite similar surface areas available for cell attachment, higher cell concentrations in 3D reduced MSCs proliferation, while activating hypoxia related-pathways. To further understand the in vivo effects of both proliferation and cell concentrations, we increased cell concentrations in small (1.8 µl) implantable wells. We found that MSCs accumulation and conditioning by nutrient competition in small volumes leads to an ideal threshold of cell-concentration for the induction of blood vessel formation, possibly signaled by the hypoxia-related stanniocalcin-1 gene.


Asunto(s)
Técnicas de Cultivo Celular por Lotes/métodos , Medios de Cultivo/farmacocinética , Glicoproteínas/biosíntesis , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Neovascularización Fisiológica/fisiología , Adaptación Fisiológica/fisiología , Disponibilidad Biológica , Proliferación Celular/fisiología , Células Cultivadas , Diseño de Equipo , Humanos , Análisis Espacio-Temporal , Andamios del Tejido
18.
Biol Psychol ; 99: 1-14, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24561100

RESUMEN

Many studies show that respiratory sinus arrhythmia (RSA) decreases while performing cognitive tasks. However, there is uncertainty about the role of contaminating factors such as physical activity and stress-inducing task variables. Different methods to quantify RSA may also contribute to variable results. In 83 healthy subjects, we studied RSA responses to a working memory task requiring varying levels of cognitive control and a perceptual attention task not requiring strong cognitive control. RSA responses were quantified in the time and frequency domain and were additionally corrected for differences in mean interbeat interval and respiration rate, resulting in eight different RSA indices. The two tasks were clearly differentiated by heart rate and facial EMG reference measures. Cognitive control induced inhibition of RSA whereas perceptual attention generally did not. However, the results show several differences between different RSA indices, emphasizing the importance of methodological variables. Age and sex did not influence the results.


Asunto(s)
Atención/fisiología , Cognición/fisiología , Arritmia Sinusal Respiratoria/fisiología , Adolescente , Adulto , Factores de Edad , Análisis de Varianza , Arritmia Sinusal/fisiopatología , Electrocardiografía , Electromiografía , Músculos Faciales/fisiología , Femenino , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Respiración , Adulto Joven
19.
J Abnorm Child Psychol ; 40(2): 211-23, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21870040

RESUMEN

This study examined empathy-related responding in male adolescents with disruptive behavior disorder (DBD), high or low on callous-unemotional (CU) traits. Facial electromyographic (EMG) and heart rate (HR) responses were monitored during exposure to empathy-inducing film clips portraying sadness, anger or happiness. Self-reports were assessed afterward. In agreement with expectations, DBD adolescents with high CU traits showed significantly lower levels of empathic sadness than healthy controls across all response systems. Between DBD subgroups significant differences emerged at the level of autonomic (not verbal or facial) reactions to sadness, with high CU respondents showing less HR change from baseline than low CU respondents. The study also examined basal patterns of autonomic function. Resting HR was not different between groups, but resting respiratory sinus arrhythmia (RSA) was significantly lower in DBD adolescents with high CU traits compared to controls. Results support the notion that CU traits designate a distinct subgroup of DBD individuals.


Asunto(s)
Conducta del Adolescente/psicología , Déficit de la Atención y Trastornos de Conducta Disruptiva/psicología , Emociones/fisiología , Empatía , Expresión Facial , Frecuencia Cardíaca/fisiología , Adolescente , Conducta del Adolescente/fisiología , Afecto/fisiología , Análisis de Varianza , Déficit de la Atención y Trastornos de Conducta Disruptiva/fisiopatología , Niño , Electromiografía , Humanos , Masculino , Películas Cinematográficas , Conducta Verbal
20.
Biol Psychol ; 91(1): 128-41, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22683526

RESUMEN

The literature shows large inconsistencies in respiratory sinus arrhythmia (RSA) responses to induced emotional states. This may be caused by differences in emotion induction methods, RSA quantification, and non-emotional demands of the situation. In 83 healthy subjects, we studied RSA responses to pictures and film fragments eliciting six different discrete emotions relative to neutral baseline stimuli. RSA responses were quantified in the time and frequency domain and were additionally corrected for differences in mean heart rate and respiration rate, resulting in eight different RSA response measures. Subjective ratings of emotional stimuli and facial electromyographic responses indicated that pictures and film fragments elicited the intended emotions. Although RSA measures showed various emotional effects, responses were quite heterogeneous and frequently nonsignificant. They were substantially influenced by methodological factors, in particular time vs. frequency domain response measures, correction for changes in respiration rate, use of pictures vs. film fragments, and sex of participants.


Asunto(s)
Nivel de Alerta/fisiología , Emociones/fisiología , Frecuencia Cardíaca/fisiología , Respiración , Adolescente , Adulto , Factores de Edad , Femenino , Respuesta Galvánica de la Piel/fisiología , Humanos , Masculino , Persona de Mediana Edad , Frecuencia Respiratoria , Factores Sexuales
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