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1.
J Ultrasound Med ; 40(5): 1023-1030, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32959920

RESUMO

OBJECTIVES: To determine contrast enhancing features of mediastinal masses (ML) using transcutaneous contrast-enhanced ultrasound (CEUS). METHODS: Retrospective analysis of n = 58 patients with histologically confirmed ML, which were examined in the period from October 2005 to February 2018 using transcutaneous B-mode ultrasound and CEUS. In n = 29 (50%) histological confirmation was performed by ultrasound guided core-needle biopsy. The lesions were evaluated using CEUS in regard to the enhancement pattern (hyper-, iso-, hypoenhancement, non-enhancement, homogenous, inhomogenous) compared to enhancement of the spleen as an in vivo reference. RESULTS: N = 53 (91.4%) of ML were malignant (m) (lymphoma n = 36, metastasis n = 11, thymoma n = 2, teratoma n = 1, sarcoma n = 2, seminoma n = 1). In n = 5 (8.6%) cases there was a benign (b) histology (thyroid tissue n = 2, thymus residue n = 1, ganglioneurinoma n = 1, scar tissue: n = 1). In ultrasound, n = 53 (91.4%; (48 = m, 5 = b)) were hypoechoic, n = 5 (8.6%, (5 = m,0 = b)) hyperechoic. In CEUS, n = 35 lesions presented an arterial isoenhancement (60.3%; 33 = m, 2 = b). An arterial hypoenhancement had n = 21 (36.2%, (20 = m,1 = b)), and no enhancement showed n = 2 (3.5%, (0 = m, 2 = b) of the ML. A parenchymal isoenhancement was observed in n = 1 (1.7%, (1 = m, 0 = b)), a hypoenhancement in n = 54 (93.1%; 51 = m, 3 = b) of the patients and almost no enhancement in n = 3 ML (5.2%, (1 = m, 2 = b).) The enhancement was homogeneous in n = 26 (44.8%, (25 = m,1 = b)) cases, in n = 31 (53.5%, (28 = m,3 = b)) inhomogeneous and n = 1 (1.7%) benign lesion was exclusively cystic. CONCLUSION: In CEUS, mediastinal tumor formations showed variable arterial enhancement, followed by parenchymal hypoenhancement (wash-out).


Assuntos
Aumento da Imagem , Linfoma , Meios de Contraste , Humanos , Estudos Retrospectivos , Ultrassonografia
2.
Aust Crit Care ; 34(2): 167-175, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33250401

RESUMO

BACKGROUND: There are large uncertainties with regard to the outcome of patients with coronavirus disease 2019 (COVID-19) and mechanical ventilation (MV). High mortality (50-97%) was proposed by some groups, leading to considerable uncertainties with regard to outcomes of critically ill patients with COVID-19. OBJECTIVES: The aim was to investigate the characteristics and outcomes of critically ill patients with COVID-19 requiring intensive care unit (ICU) admission and MV. METHODS: A multicentre retrospective observational cohort study at 15 hospitals in Hamburg, Germany, was performed. Critically ill adult patients with COVID-19 who completed their ICU stay between February and June 2020 were included. Patient demographics, severity of illness, and ICU course were retrospectively evaluated. RESULTS: A total of 223 critically ill patients with COVID-19 were included. The majority, 73% (n = 163), were men; the median age was 69 (interquartile range = 58-77.5) years, with 68% (n = 151) patients having at least one chronic medical condition. Their Sequential Organ Failure Assessment score was a median of 5 (3-9) points on admission. Overall, 167 (75%) patients needed MV. Noninvasive ventilation and high-flow nasal cannula were used in 31 (14%) and 26 (12%) patients, respectively. Subsequent MV, due to noninvasive ventilation/high-flow nasal cannula therapy failure, was necessary in 46 (81%) patients. Renal replacement therapy was initiated in 33% (n = 72) of patients, and owing to severe respiratory failure, extracorporeal membrane oxygenation was necessary in 9% (n = 20) of patients. Experimental antiviral therapy was used in 9% (n = 21) of patients. Complications during the ICU stay were as follows: septic shock (40%, n = 90), heart failure (8%, n = 17), and pulmonary embolism (6%, n = 14). The length of ICU stay was a median of 13 days (5-24), and the duration of MV was 15 days (8-25). The ICU mortality was 35% (n = 78) and 44% (n = 74) among mechanically ventilated patients. CONCLUSION: In this multicentre observational study of 223 critically ill patients with COVID-19, the survival to ICU discharge was 65%, and it was 56% among patients requiring MV. Patients showed high rate of septic complications during their ICU stay.


Assuntos
COVID-19/mortalidade , COVID-19/terapia , Estado Terminal , Pneumonia Viral/mortalidade , Pneumonia Viral/terapia , Respiração Artificial , Idoso , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/virologia , Estudos Retrospectivos , SARS-CoV-2
3.
Exp Brain Res ; 232(3): 957-73, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24408441

RESUMO

Stress and additional load on the executive system, produced by a parallel working memory task, impair decision making under risk. However, the combination of stress and a parallel task seems to preserve the decision-making performance [e.g., operationalized by the Game of Dice Task (GDT)] from decreasing, probably by a switch from serial to parallel processing. The question remains how the brain manages such demanding decision-making situations. The current study used a 7-tesla magnetic resonance imaging (MRI) system in order to investigate the underlying neural correlates of the interaction between stress (induced by the Trier Social Stress Test), risky decision making (GDT), and a parallel executive task (2-back task) to get a better understanding of those behavioral findings. The results show that on a behavioral level, stressed participants did not show significant differences in task performance. Interestingly, when comparing the stress group (SG) with the control group, the SG showed a greater increase in neural activation in the anterior prefrontal cortex when performing the 2-back task simultaneously with the GDT than when performing each task alone. This brain area is associated with parallel processing. Thus, the results may suggest that in stressful dual-tasking situations, where a decision has to be made when in parallel working memory is demanded, a stronger activation of a brain area associated with parallel processing takes place. The findings are in line with the idea that stress seems to trigger a switch from serial to parallel processing in demanding dual-tasking situations.


Assuntos
Mapeamento Encefálico , Transtornos Cognitivos/diagnóstico , Tomada de Decisões/fisiologia , Função Executiva/fisiologia , Estresse Psicológico/complicações , Estresse Psicológico/patologia , Adolescente , Adulto , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Hidrocortisona/metabolismo , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Escalas de Graduação Psiquiátrica , Saliva/metabolismo , Adulto Jovem
4.
Neuroimage ; 74: 152-63, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23428568

RESUMO

Food labeling is the major health policy strategy to counter rising obesity rates. Based on traditional economic theory, such strategies assume that detailed nutritional information will necessarily help individuals make better, healthier choices. However, in contrast to the well-known utility of labels in food marketing, evidence for the efficacy of nutritional labeling is mixed. Psychological and behavioral economic theories suggest that successful marketing strategies activate automatic decision biases and emotions, which involve implicit emotional brain systems. Accordingly, simple, intuitive food labels that engage these neural systems could represent a promising approach for promoting healthier choices. Here we used functional MRI to investigate this possibility. Healthy, mildly hungry subjects performed a food evaluation task and a food choice task. The main experimental manipulation was to pair identical foods with simple labels that emphasized either taste benefits or health-related food properties. We found that such labels biased food evaluations in the amygdala, a core emotional brain system. When labels biased the amygdala's evaluations towards health-related food properties, the strength of this bias predicted behavioral shifts towards healthier choices. At the time of decision-making, amygdala activity encoded key decision variables, potentially reflecting active amygdala participation in food choice. Our findings underscore the potential utility of food labeling in health policy and indicate a principal role for emotional brain systems when labels guide food choices.


Assuntos
Tonsila do Cerebelo/fisiologia , Mapeamento Encefálico , Comportamento de Escolha/fisiologia , Rotulagem de Alimentos , Comportamentos Relacionados com a Saúde , Adulto , Emoções/fisiologia , Feminino , Política de Saúde , Promoção da Saúde/métodos , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
5.
Appl Neuropsychol Adult ; 21(4): 241-59, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25265306

RESUMO

In neuropsychological decision-making research, several different tasks are used to measure decision-making competences in patients and healthy study participants. Unfortunately, the existing tasks are often inflexible for modification, use different scenarios, and include several gambling cues. Therefore, comparisons between participants' performances in different tasks are difficult. We developed the Truck Dispatcher Framework (TDF), in which different decision-making tasks can be designed within one unitary, flexible, and real-world-oriented story line. To test the story line, TDF analogues of three standard decision-making tasks (Game of Dice Task, Probability-Associated Gambling task, Iowa Gambling Task) were developed. In three studies with brain-healthy participants, the behavior in standard decision-making tasks and the TDF analogues of those tasks were compared. Similar behaviors indicate that the TDF tasks measure decision making appropriately. Thus, the TDF is recommended for experimental and clinical research because it allows for examining decision-making competences in tasks with different demands that take place within one unitary story line.


Assuntos
Tomada de Decisões/fisiologia , Julgamento/fisiologia , Testes Neuropsicológicos , Meios de Transporte , Adolescente , Adulto , Idoso , Análise de Variância , Tomada de Decisões Assistida por Computador , Feminino , Jogos Experimentais , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Resolução de Problemas , Reprodutibilidade dos Testes , Assunção de Riscos , Meios de Transporte/economia , Adulto Jovem
6.
J Sex Res ; 50(7): 642-52, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23167900

RESUMO

Some individuals report problems during and after Internet sex engagement, such as missing sleep and forgetting appointments, which are associated with negative life consequences. One mechanism potentially leading to these kinds of problems is that sexual arousal during Internet sex might interfere with working memory (WM) capacity, resulting in a neglect of relevant environmental information and therefore disadvantageous decision making. In this study, 28 healthy individuals performed 4 experimental manipulations of a pictorial 4-back WM task with neutral, negative, positive, or pornographic stimuli. Participants also rated 100 pornographic pictures with respect to sexual arousal and indicated masturbation urges previous to and following pornographic picture presentation. Results revealed worse WM performance in the pornographic picture condition of the 4-back task compared with the three remaining picture conditions. Furthermore, hierarchical regression analysis indicated an explanation of variance of the sensitivity in the pornographic picture condition by the subjective rating of the pornographic pictures as well as by a moderation effect of masturbation urges. Results contribute to the view that indicators of sexual arousal due to pornographic picture processing interfere with WM performance. Findings are discussed with respect to Internet sex addiction because WM interference by addiction-related cues is well known from substance dependencies.


Assuntos
Nível de Alerta/fisiologia , Literatura Erótica/psicologia , Memória de Curto Prazo/fisiologia , Sexualidade/psicologia , Análise e Desempenho de Tarefas , Adulto , Humanos , Masculino , Adulto Jovem
7.
J Behav Addict ; 2(2): 100-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26165929

RESUMO

Background and aims Cybersex addiction is discussed controversially, while empirical evidence is widely missing. With respect to its mechanisms of development and maintenance Brand et al. (2011) assume that reinforcement due to cybersex should lead to the development of cue-reactivity and craving explaining recurrent cybersex use in the face of growing but neglected negative consequences. To support this hypothesis, two experimental studies were conducted. Methods In a cue-reactivity paradigm 100 pornographic cues were presented to participants and indicators of sexual arousal and craving were assessed. The first study aimed at identifying predictors of cybersex addiction in a freely recruited sample of 171 heterosexual males. The aim of the second study was to verify the findings of the first study by comparing healthy (n = 25) and problematic (n = 25) cybersex users. Results The results show that indicators of sexual arousal and craving to Internet pornographic cues predicted tendencies towards cybersex addiction in the first study. Moreover, it was shown that problematic cybersex users report greater sexual arousal and craving reactions resulting from pornographic cue presentation. In both studies, the number and subjective quality of real-life sexual contacts were not associated to cybersex addiction. Discussion The results support the gratification hypothesis, which assumes reinforcement, learning mechanisms, and craving to be relevant processes in the development and maintenance of cybersex addiction. Poor or unsatisfying sexual real-life contacts cannot sufficiently explain cybersex addiction. Conclusions Positive reinforcement in terms of gratification plays a major role in cybersex addiction.

8.
Front Behav Neurosci ; 7: 24, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23580061

RESUMO

MEMORY RESEARCH HAS BEEN GUIDED BY TWO POWERFUL METAPHORS: the storehouse (computer) and the correspondence metaphor. The latter emphasizes the dependability of retrieved mnemonic information and draws upon ideas about the state dependency and reconstructive character of episodic memory. We used a new movie to unveil the neural correlates connected with retrieval, monitoring, and control processes, and memory accuracy (MAC), according to the paradigm of Koriat and Goldsmith (1996a,b). During functional magnetic resonance imaging, subjects performed a memory task which required (after an initial learning phase) rating true and false statements [retrieval phase (RP)], making confidence judgments in the respective statement [monitoring phase (MP)], and deciding for either venturing (volunteering) the respective answer or withholding the response [control phase (CP)]. Imaging data pointed to common and unique neural correlates. Activations in brain regions related to RP and MAC were observed in the precuneus, middle temporal gyrus, and left hippocampus. MP was associated with activation in the left anterior and posterior cingulate cortex along with bilateral medial temporal regions. If an answer was volunteered (as opposed to being withheld) during the CP, temporal, and frontal as well as middle and posterior cingulate areas and the precuneus revealed activations. Increased bilateral hippocampal activity was found during withholding compared to volunteering answers. The left caudate activation detected during withholding compared to venturing an answer supports the involvement of the left caudate in inhibiting unwanted responses. Contrary to expectations, we did not evidence prefrontal activations during withholding (as opposed to volunteering) answers. This may reflect our design specifications, but alternative interpretations are put forth.

10.
Hum Factors ; 49(1): 136-44, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17315850

RESUMO

OBJECTIVE: We experimentally tested the degree that the size-weight illusion depends on perceptual conditions allowing the observer to assume that both the visual and the kinesthetic stimuli of a weight seen and lifted emanate from the same object. We expected that the degree of the illusion depended on the "realism" provided by different kinds of virtual reality (VR) used when the weights are seen in virtual reality and at the same time lifted in natural reality. BACKGROUND: Welch and Warren (1980) reported that an intermodal influence can be expected only if perceptual information of different modalities is compellingly related to only one object. METHOD: Objects of different sizes and weights were presented to 50 participants in natural reality or in four virtual realities: two immersive head-mounted display VRs (with or without head tracking) and two nonimmersive desktop VRs (with or without screening from input of the natural environment using a visor). The objects' heaviness was scaled using the magnitude estimation method. RESULTS: Data show that the degree of the illusion is largest in immersive and lowest in nonimmersive virtual realities. CONCLUSION: The higher the degree of the illusion is, the more compelling the situation is perceived and the more the observed data are in correspondence with the data predicted for the illusion in natural reality. This shows that the kind of mediating technology used strongly influences the presence experienced. APPLICATION: The size-weight illusion's sensitivity to conditions that affect the sense of presence makes it a promising objective presence measure.


Assuntos
Gráficos por Computador , Ilusões , Percepção de Tamanho , Interface Usuário-Computador , Percepção de Peso , Adulto , Feminino , Humanos , Masculino
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