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1.
Cogn Emot ; 38(2): 217-231, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37987765

RESUMO

Two recent articles [Gronchi et al., 2018. Automatic and controlled attentional orienting in the elderly: A dual-process view of the positivity effect. Acta Psychologica, 185, 229-234; Wirth & Wentura, 2020. It occurs after all: Attentional bias towards happy faces in the dot-probe task. Attention, Perception, & Psychophysics, 82(5), 2463-2481] report attentional biases for happy facial expressions in the dot-probe paradigm, albeit in different directions. While Wirth and Wentura report a bias towards happy expressions, Gronchi et al. found a reversed effect. A striking difference between the studies was the task performed by the participants. While in Wirth and Wentura, participants performed a discrimination task, they performed a location task in Gronchi et al. In Experiment 1, we directly compared the two versions of the dot-probe paradigm. With the discrimination task, the bias towards happy faces was replicated. However, the location task yielded a null effect. In Experiment 2, we found a cueing effect with an abrupt onset cue in both tasks. However, for the location task a congruence-sequence effect (a typical characteristic of response-priming processes) occurred. This result suggests that in the location task, attentional processes are confounded with response-priming processes. We recommend to generally use discrimination tasks.


Assuntos
Viés de Atenção , Humanos , Idoso , Emoções , Tempo de Reação , Atenção , Felicidade , Expressão Facial
2.
Soc Cogn Affect Neurosci ; 18(1)2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-37971294

RESUMO

Previous research has shown that attentional bias towards angry faces is moderated by the activation of a social processing mode. More specifically, reliable cueing effects for angry face cues in the dot-probe task only occurred when participants performed a task that required social processing of the target stimuli. However, cueing effects are a rather distal measure of covert shifts in spatial attention. Thus, it remains unclear whether the social processing mode modulates initial allocation of attention to or attentional disengagement from angry faces. In the present study, we used the N2pc, an event-related potential component, as an index of attentional shifts towards angry faces. Participants performed a dot-probe task with two different target conditions while the electroencephalogram (EEG) was recorded. In the social target condition, target stimuli were socially meaningful (schematic faces), and in the non-social target condition, they were meaningless (scrambled schematic faces). The amplitude of the N2pc component elicited by angry face cues was significantly larger in the social target condition than in the non-social target condition. This pattern also occurred for behavioural cueing effects. These results suggest that the activation of a social processing mode due to current task demands affects the initial allocation of attention towards angry faces.


Assuntos
Ira , Expressão Facial , Humanos , Tempo de Reação/fisiologia , Estimulação Luminosa/métodos , Ira/fisiologia , Eletroencefalografia
3.
Artigo em Inglês | MEDLINE | ID: mdl-37814081

RESUMO

Climate change, COVID-19, and the Russia-Ukraine War are some of the great challenges of our time. These global crises affect young people in a particularly vulnerable phase of their lives. The current study aimed to assess the impact of these crises on mental health (depression, anxiety, and health-related quality of life) in secondary school students in Germany. Furthermore, we assessed known predictors of mental health, such as socio-economic factors, individual life stressors, and resilience factors (self-efficacy, expressive flexibility) as covariates. In our sample of 3998 pupils, pandemic- and climate-related distress were linked to greater depression and anxiety and reduced health-related quality of life. War-related distress was associated with greater anxiety. Critically, these associations remained significant after controlling for all covariates, supporting the incremental predictive value of the crises measures. The study reveals a significant impact of the crises on the mental health of the current generation of adolescents. As such it suggests that mental health policies should include interventions that help youth to cope with the stress caused by the crises.

4.
Behav Res Ther ; 167: 104359, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37422952

RESUMO

Distressing intrusive memories of a traumatic event are one of the hallmark symptoms of posttraumatic stress disorder. Thus, it is crucial to identify early interventions that prevent the occurrence of intrusive memories. Both, sleep and sleep deprivation have been discussed as such interventions, yet previous studies yielded contradicting effects. Our systematic review aims at evaluating existing evidence by means of traditional and individual participant data (IPD) meta-analyses to overcome power issues of sleep research. Until May 16th, 2022, six databases were searched for experimental analog studies examining the effect of post-trauma sleep versus wakefulness on intrusive memories. Nine studies were included in our traditional meta-analysis (8 in the IPD meta-analysis). Our analysis provided evidence for a small effect favoring sleep over wakefulness, log-ROM = 0.25, p < .001, suggesting that sleep is associated with a lower number of intrusions but unrelated to the occurrence of any versus no intrusions. We found no evidence for an effect of sleep on intrusion distress. Heterogeneity was low and certainty of evidence for our primary analysis was moderate. Our findings suggest that post-trauma sleep has the potential to be protective by reducing intrusion frequency. More research is needed to determine the impact following real-world trauma and the potential clinical significance.


Assuntos
Memória , Transtornos de Estresse Pós-Traumáticos , Humanos , Sono , Privação do Sono , Cognição
5.
J Exp Psychol Hum Percept Perform ; 49(8): 1145-1157, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37338430

RESUMO

Prior experience has a strong impact on search performance, and most recent models of attention incorporate selection history as an important source of attentional guidance. Here, we focused on feature intertrial priming, a robust effect showing that responses to a singleton target are considerably faster when its unique feature repeats versus changes across successive trials. Previous studies showed that such target repetition does not reliably reduce the interference exerted by a salient distractor. This finding has been taken to indicate that target repetition does not enhance the target's competitive edge relative to the salient distractor. Therefore, it challenges the notion that intertrial priming modulates attentional priority. Here, we suggest that this inference may be misguided because the interpretation of distractor interference as a measure of the attentional priority of the salient distractor relative to the target is incorrect. To obtain a more direct measure of the impact of feature intertrial priming on the target's priority relative to a salient distractor and nontargets, we used the capture-probe paradigm. Across two experiments, probe reports from the target location increased at the expense of the salient distractor and nontarget locations when the target feature repeated versus changed, whereas distractor interference was unaffected. These findings show that feature intertrial repetition influences attentional priority. They also clearly illustrate that distractor interference indexes the priority of the salient distractor relative to the nontarget it replaces, not relative to the target-a reinterpretation that has important implications for the field of attentional capture. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Atenção , Viés de Atenção , Humanos , Tempo de Reação/fisiologia , Atenção/fisiologia , Viés
6.
Behav Res Ther ; 154: 104098, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35617768

RESUMO

Humans try to make sense of the world using hypotheses that were formed by prior experiences. After trauma, these hypotheses can be exaggerated and resistant to change. This may result in difficulties to update expectations regarding the negative outcomes associated with traumatic stimuli. Critically, it has been proposed that such difficulties may drive the development of posttraumatic stress disorder (PTSD). However, direct evidence on the associations between trauma and impaired expectation updating is still absent. Moreover, it remains unclear whether such an impairment is correlated with PTSD symptoms. To address these gaps, we compared the ability to update traumatic and neutral stimulus-outcome expectations in 81 active-duty firefighters. Participants completed a performance-based updating task and were assessed for PTSD symptoms. We predicted and found a selective impairment in updating trauma-related expectations. This impairment was evident for negative-to-positive but not for positive-to-negative updating. Moreover, impaired negative-to-positive updating was positively associated with PTSD symptoms. These findings support the predictive processing account of PTSD and suggest that strengthening updating processes could be an important goal for promoting resilience after trauma.


Assuntos
Bombeiros , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico
7.
Math Med Biol ; 38(2): 218-254, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33601409

RESUMO

Blebs are cell protrusions generated by local membrane-cortex detachments followed by expansion of the plasma membrane. Blebs are formed by some migrating cells, e.g. primordial germ cells of the zebrafish. While blebs occur randomly at each part of the membrane in unpolarized cells, a polarization process guarantees the occurrence of blebs at a preferential site and thereby facilitates migration toward a specified direction. Little is known about the factors involved in the controlled and directed bleb generation, yet recent studies revealed the influence of an intracellular flow and the stabilizing role of the membrane-cortex linker molecule Ezrin. Based on this information, we develop and analyse a coupled bulk-surface model describing a potential cellular mechanism by which a bleb could be induced at a controlled site. The model rests upon intracellular Darcy flow and a diffusion-advection-reaction system, describing the temporal evolution from a homogeneous to a strongly anisotropic Ezrin distribution. We prove the well-posedness of the mathematical model and show that simulations qualitatively correspond to experimental observations, suggesting that indeed the interaction of an intracellular flow with membrane proteins can be the cause of the Ezrin redistribution accompanying bleb formation.


Assuntos
Peixe-Zebra , Animais , Extensões da Superfície Celular , Células Germinativas , Modelos Teóricos
8.
BMC Bioinformatics ; 21(1): 335, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727350

RESUMO

BACKGROUND: The efficient and robust statistical analysis of the shape of plant organs of different cultivars is an important investigation issue in plant breeding and enables a robust cultivar description within the breeding progress. Laserscanning is a highly accurate and high resolution technique to acquire the 3D shape of plant surfaces. The computation of a shape based principal component analysis (PCA) built on concepts from continuum mechanics has proven to be an effective tool for a qualitative and quantitative shape examination. RESULTS: The shape based PCA was used for a statistical analysis of 140 sugar beet roots of different cultivars. The calculation of the mean sugar beet root shape and the description of the main variations was possible. Furthermore, unknown and individual tap roots could be attributed to their cultivar by means of a robust classification tool based on the PCA results. CONCLUSION: The method demonstrates that it is possible to identify principal modes of root shape variations automatically and to quantify associated variances out of laserscanned 3D sugar beet tap root models. The introduced approach is not limited to the 3D shape description by laser scanning. A transfer to 3D MRI or radar data is also conceivable.


Assuntos
Beta vulgaris/anatomia & histologia , Lasers , Raízes de Plantas/anatomia & histologia , Estatística como Assunto , Análise de Componente Principal
9.
Inorg Chem ; 59(12): 8387-8395, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32463666

RESUMO

The niobium tellurium oxides ANbTeO6 with varying A cations (A = K, Rb, Cs) and defect-pyrochlore crystal structure were used to investigate the effect of A on crystal-structure deformation and defect-chemistry. We show that the light absorption of these compounds in visible light is due to defects and not the effect of a low band gap. Using the materials in photocatalytic hydrogen generation, the prevailing defects and the surface composition change significantly during photocatalytic hydrogen evolution.

10.
Atten Percept Psychophys ; 82(5): 2463-2481, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32236834

RESUMO

Many studies have shown that not only threatening but also positive stimuli capture visual attention. However, in the dot-probe task, a common paradigm to assess attention to emotional stimuli, usually no bias towards happy faces occurs. Here, we investigated whether such a bias can occur and, if so, under which conditions. In Experiment 1, we investigated whether the bias is contingent on the simultaneous presentation of distractor stimuli with the targets. Participants performed a dot-probe task with either stand-alone targets or targets that were accompanied by distractors. We found an attentional bias towards happy faces that was not moderated by target type. To rule out perceptual low-level confounds as the cause of the bias towards happy faces, Experiments 2a and 2b comprised dot-probe tasks with inverted face cues. No attentional bias towards inverted happy faces occurred. In Experiment 3, we investigated whether a bias towards happy faces is contingent on a social-processing mode. Participants performed a dot-probe task with socially meaningful (schematic faces) or socially meaningless (scrambled schematic faces) targets. Again, a bias towards happy faces, which was not moderated by target type, occurred. In Experiment 4, we investigated the attentional bias towards happy faces when another highly relevant expression was present. Participants performed a dot-probe task with both happy and angry face cues. A significant attentional bias towards emotional faces occurred that did not differ between both cue emotions. These results suggest that happy faces are sufficiently relevant for observers to capture attention in the dot-probe task.


Assuntos
Viés de Atenção , Expressão Facial , Emoções , Humanos , Estimulação Luminosa , Tempo de Reação
11.
Sleep Med Rev ; 51: 101280, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32179376

RESUMO

Numerous studies have shown that post-learning sleep enhances visual episodic recognition memory. However, it remains unclear whether this consolidation benefit is moderated by the emotional valence of the learned material. To clarify whether sleep selectively enhances memory for emotional material, we conducted a meta-analysis including N = 1059 post-sleep/wake observations. Overall, our results do not support this hypothesis. When only studies with a sleep group/wake group comparison were included in the analysis (k = 22), the retention advantage for emotional (negative/positive) over neutral material was not significantly different between sleep and wake groups. When studies without wake groups were included in the analysis after statistical estimation of wake-group parameters, the retention advantage for emotional material was significantly larger in wake groups than in sleep groups (k = 34). Interestingly, however, an additional analysis of eight studies investigating the selective effects of rapid-eye-movement sleep and slow-wave sleep on post-interval emotional memory provided evidence for a selective enhancement of emotional over neutral memory performance after rapid-eye-movement sleep compared to slow-wave sleep. These findings suggest that sleep does not generally enhance visual recognition memory for emotional stimuli. However, the result pattern is consistent with the idea that specific sleep stages preferentially enhance consolidation of emotional and neutral material, respectively.


Assuntos
Emoções , Consolidação da Memória , Memória/fisiologia , Sono REM/fisiologia , Sono/fisiologia , Eletroencefalografia , Humanos , Sono de Ondas Lentas
12.
IEEE Trans Med Imaging ; 39(5): 1626-1635, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31751230

RESUMO

We propose a novel dynamic image reconstruction method from PET listmode data that could be particularly suited to tracking single or small numbers of cells. In contrast to conventional PET reconstruction our method combines the information from all detected events not only to reconstruct the dynamic evolution of the radionuclide distribution, but also to improve the reconstruction at each single time point by enforcing temporal consistency. This is achieved via optimal transport regularization where in principle, among all possible temporally evolving radionuclide distributions consistent with the PET measurement, the one is chosen with least kinetic motion energy. The reconstruction is found by convex optimization so that there is no dependence on the initialization of the method. We study its behaviour on simulated data of a human PET system and demonstrate its robustness even in settings with very low radioactivity. In contrast to previously reported cell tracking algorithms, our technique is oblivious to the number of tracked cells. Without any additional complexity one or multiple cells can be reconstructed, and the model automatically determines the number of particles. For instance, four radiolabelled cells moving at a velocity of 3.1 mm/s and a PET recorded count rate of 1.1 cps (for each cell) could be simultaneously tracked with a tracking accuracy of 5.3 mm inside a simulated human body.


Assuntos
Algoritmos , Tomografia por Emissão de Pósitrons , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Imagens de Fantasmas
13.
Cell Rep ; 29(4): 1010-1026.e6, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31644899

RESUMO

Actin-binding proteins are essential for linear and branched actin filament dynamics that control shape change, cell migration, and cell junction remodeling in vascular endothelium (endothelial cells [ECs]). The epithelial protein lost in neoplasm (EPLIN) is an actin-binding protein, expressed as EPLIN-α and EPLIN-ß by alternative promoters; however, the isoform-specific functions are not yet understood. Aortic compared to cava vein ECs and shear stress-exposed cultured ECs express increased EPLIN-ß levels that stabilize stress fibers. In contrast, EPLIN-α expression is increased in growing and migrating ECs, is targeted to membrane protrusions, and terminates their growth via interaction with the Arp2/3 complex. The data indicate that EPLIN-α controls protrusion dynamics while EPLIN-ß has an actin filament stabilizing role, which is consistent with FRAP analyses demonstrating a lower EPLIN-ß turnover rate compared to EPLIN-α. Together, EPLIN isoforms differentially control actin dynamics in ECs, essential in shear stress responses, cell migration, and barrier function.


Assuntos
Actinas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Endotélio Vascular/metabolismo , Animais , Aorta/citologia , Aorta/metabolismo , Proliferação de Células , Proteínas do Citoesqueleto/genética , Endotélio Vascular/citologia , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fibras de Estresse/metabolismo
14.
Cogn Emot ; 33(7): 1317-1329, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30587095

RESUMO

Dot-probe studies usually find an attentional bias towards threatening stimuli only in anxious participants, but not in non-anxious participants. In the present study, we conducted two experiments to investigate whether attentional bias towards angry faces in unselected samples is moderated by the extent to which the current task requires social processing. In Experiment 1, participants performed a dot-probe task involving classification of either socially meaningful targets (schematic faces) or meaningless targets (scrambled schematic faces). Targets were preceded by two photographic face cues, one angry and one neutral. Angry face cues only produced significant cueing scores (i.e. faster target responses if the target replaced the angry face compared to the neutral face) with socially meaningful targets, not with meaningless targets. In Experiment 2, participants classified only meaningful targets, which were either socially meaningful (schematic faces) or not (schematic houses). Again, mean cueing scores were significantly moderated by the social character of the targets. However, cueing scores in this experiment were non-significant in the social target condition and significantly negative in the non-social target condition. These results suggest that attentional bias towards angry faces in the dot-probe task is moderated by the activation of a social processing mode in unselected samples.


Assuntos
Ira , Viés de Atenção/fisiologia , Sinais (Psicologia) , Expressão Facial , Percepção Social , Adolescente , Adulto , Ansiedade , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Estudantes/psicologia , Adulto Jovem
15.
PLoS One ; 13(11): e0207695, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30481190

RESUMO

Dot-probe studies consistently show that high trait anxious individuals have an attentional bias towards threatening faces. However, little is known about the influence of perceptual confounds of specific emotional expressions on this effect. Teeth-exposure was recently recognized as an important factor for the occurrence of attentional bias towards angry faces in a closely related paradigm (the face-in-the-crowd paradigm). Therefore, we investigated the effect of exposed teeth on attentional bias towards angry faces in the dot-probe task. Participants (N = 74) were asked to classify probe stimuli that were preceded by two simultaneously presented face cues, one angry and the other neutral. Half of the angry faces had exposed teeth, the other half had concealed teeth. Afterwards, participants completed the trait anxiety scale of the STAI. For angry faces with non-exposed teeth, we found the expected positive correlation (r = .441) of trait anxiety with the attentional bias score (reaction times for probes replacing the neutral face minus reaction times for probes replacing the angry face). However, we found no influence of trait anxiety on attentional bias towards angry faces with exposed teeth. These results suggest that natural low-level stimulus confounds of emotional faces like exposed teeth can affect the manifestation of anxiety-related attentional biases towards angry faces in the dot-probe task.


Assuntos
Ira/fisiologia , Ansiedade/fisiopatologia , Viés de Atenção/fisiologia , Emoções/fisiologia , Expressão Facial , Adulto , Ansiedade/psicologia , Sinais (Psicologia) , Face , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
16.
Q J Exp Psychol (Hove) ; 71(4): 975-988, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28303742

RESUMO

Dot-probe studies usually find an attentional bias towards threatening stimuli only in anxious participants. Here, we investigated under what conditions such a bias occurs in unselected samples. According to contingent-capture theory, an irrelevant cue only captures attention if it matches an attentional control setting. Therefore, we first tested the hypothesis that an attentional control setting tuned to threat must be activated in (non-anxious) individuals. In Experiment 1, we used a dot-probe task with a manipulation of attentional control settings ('threat' - set vs. control set). Surprisingly, we found an (anxiety-independent) attentional bias to angry faces that was not moderated by attentional control settings. Since we presented two stimuli (i.e., a target and a distractor) on the target screen in Experiment 1 (a necessity to realise the test of contingent capture), but most dot-probe studies only employ a single target, we conducted Experiment 2 to test the hypothesis that attentional bias in the general population is contingent on target competition. Participants performed a dot-probe task, involving presentation of a stand-alone target or a target competing with a distractor. We found an (anxiety-independent) attentional bias towards angry faces in the latter but not the former condition. This suggests that attentional bias towards angry faces in unselected samples is not contingent on attentional control settings but on target competition.


Assuntos
Ira/fisiologia , Atenção/fisiologia , Viés de Atenção , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Adulto , Análise de Variância , Ansiedade/fisiopatologia , Sinais (Psicologia) , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
17.
J Exp Psychol Appl ; 23(2): 138-157, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28368188

RESUMO

Despite extensive research on unfamiliar face matching, little is known about factors that might affect matching performance in real-life scenarios. We conducted 2 experiments to investigate the effects of several such factors on unfamiliar face-matching performance in a passport-check scenario. In Experiment 1, we assessed the effect of professional experience on passport-matching performance. The matching performance of 96 German Federal Police officers working at Munich Airport was compared with that of 48 novices without specific face-matching experience. Police officers significantly outperformed novices, but nevertheless missed a high ratio of frauds. Moreover, the effects of manipulating specific facial features (with paraphernalia like glasses and jewelry, distinctive features like moles and scars, and hairstyle) and of variations in the physical distance between the faces being matched were investigated. Whereas manipulation of physical distance did not have a significant effect, manipulations of facial features impaired matching performance. In Experiment 2, passport-matching performance was assessed in relation to time constraints. Novices matched passports either without time constraints, or under a local time limit (which is typically used in laboratory studies), or under a global time limit (which usually occurs during real-life border controls). Time pressure (especially the global time limit) significantly impaired matching performance. (PsycINFO Database Record


Assuntos
Face , Fraude , Reconhecimento Visual de Modelos , Reconhecimento Psicológico/fisiologia , Adulto , Emigração e Imigração , Feminino , Alemanha , Humanos , Masculino , Polícia , Tempo de Reação/fisiologia , Fatores de Tempo
18.
Cell Rep ; 18(5): 1256-1269, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28147279

RESUMO

Endothelial basement membranes constitute barriers to extravasating leukocytes during inflammation, a process where laminin isoforms define sites of leukocyte exit; however, how this occurs is poorly understood. In addition to a direct effect on leukocyte transmigration, we show that laminin 511 affects endothelial barrier function by stabilizing VE-cadherin at junctions and downregulating expression of CD99L2, correlating with reduced neutrophil extravasation. Binding of endothelial cells to laminin 511, but not laminin 411 or non-endothelial laminin 111, enhanced transendothelial cell electrical resistance (TEER) and inhibited neutrophil transmigration. Data suggest that endothelial adhesion to laminin 511 via ß1 and ß3 integrins mediates RhoA-induced VE-cadherin localization to cell-cell borders, and while CD99L2 downregulation requires integrin ß1, it is RhoA-independent. Our data demonstrate that molecular information provided by basement membrane laminin 511 affects leukocyte extravasation both directly and indirectly by modulating endothelial barrier properties.


Assuntos
Membrana Basal/metabolismo , Movimento Celular/fisiologia , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Laminina/metabolismo , Leucócitos/metabolismo , Animais , Antígenos CD/metabolismo , Caderinas/metabolismo , Adesão Celular/fisiologia , Células Cultivadas , Masculino , Camundongos , Camundongos Knockout , Neutrófilos/metabolismo , Neutrófilos/fisiologia
19.
Nat Commun ; 7: 10828, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26940548

RESUMO

Acute peritonitis is a frequent medical condition that can trigger severe sepsis as a life-threatening complication. Neutrophils are first-responders in infection but recruitment mechanisms to the abdominal cavity remain poorly defined. Here, we demonstrate that high endothelial venules (HEVs) of the greater omentum constitute a main entry pathway in TNFα-, Escherichia coli (E. coli)- and caecal ligation and puncture-induced models of inflammation. Neutrophil transmigration across HEVs is faster than across conventional postcapillary venules and requires a unique set of adhesion receptors including peripheral node addressin, E-, L-selectin and Mac-1 but not P-selectin or LFA-1. Omental milky spots readily concentrate intra-abdominal E. coli where macrophages and recruited neutrophils collaborate in phagocytosis and killing. Inhibition of the omental neutrophil response exacerbates septic progression of peritonitis. This data identifies HEVs as a clinically relevant vascular recruitment site for neutrophils in acute peritonitis that is indispensable for host defence against early systemic bacterial spread and sepsis.


Assuntos
Neutrófilos/fisiologia , Omento/irrigação sanguínea , Peritonite/imunologia , Sepse/imunologia , Vênulas/fisiologia , Animais , Antígenos Ly/genética , Antígenos Ly/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Escherichia coli , Infecções por Escherichia coli/imunologia , Feminino , Regulação da Expressão Gênica , Genes Transgênicos Suicidas , Masculino , Camundongos , Camundongos Knockout , Fator de Necrose Tumoral alfa/metabolismo
20.
Neuropsychologia ; 77: 387-99, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26384776

RESUMO

Misidentifications are a common phenomenon in unfamiliar face processing, but little is known about the underlying cognitive and neural mechanisms. We used the face identity-sensitive N250r component of the event-related brain potential as a measure of identity-sensitive face matching process in visual working memory. Two face images were presented in rapid succession, and participants had to judge whether they showed the same or two different individuals. Identity match and mismatch trials were presented in random sequence. On similar mismatch trials, perceptually similar faces of two different individuals were shown, while two physically distinct faces were presented on dissimilar mismatch trials. Misidentification errors occurred on 40% of all similar mismatch trials. N250r components were elicited not only in response to an identity match, but also on trials with misidentification errors. This misidentification N250r was smaller and emerged later than the N250r to correctly detected identity repetitions. Importantly, N250r components were entirely eliminated on similar mismatch trials where participants correctly reported two different facial identities. Results show that misidentification errors are not primarily a post-perceptual decision-related phenomenon, but are generated during early visual stages of identity-related face processing. Misidentification errors occur when stored representations of a particular individual face in visual working memory are incorrectly activated by a perceptual match with a different face.


Assuntos
Encéfalo/fisiologia , Reconhecimento Facial/fisiologia , Memória de Curto Prazo/fisiologia , Adulto , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Tempo de Reação
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