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1.
Photoacoustics ; 35: 100579, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38312805

RESUMO

Peripheral arterial disease (PAD) leads to chronic vascular occlusion and results in end organ damage in critically perfused limbs. There are currently no clinical methods available to determine the muscular damage induced by chronic mal-perfusion. This monocentric prospective cross-sectional study investigated n = 193 adults, healthy to severe PAD, in order to quantify the degree of calf muscle degeneration caused by PAD using a non-invasive hybrid ultrasound and single wavelength optoacoustic imaging (US/SWL-OAI) approach. While US provides morphologic information, SWL-OAI visualizes the absorption of pulsed laser light and the resulting sound waves from molecules undergoing thermoelastic expansion. US/SWL-OAI was compared to multispectral data, clinical disease severity, angiographic findings, phantom experiments, and histological examinations from calf muscle biopsies. We were able to show that synergistic use of US/SWL-OAI is most likely to map clinical degeneration of the muscle and progressive PAD.

2.
Photoacoustics ; 30: 100457, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36824387

RESUMO

Multispectral optoacoustic tomography (MSOT) holds great promise as a non-invasive diagnostic tool for inflammatory bowel diseases. Yet, reliability and the impact of physiological processes during fasting and after food intake on optoacoustic signals have not been studied. In the present investigator initiated trial (NCT05160077) the intestines of ten healthy subjects were examined by MSOT at eight timepoints on two days, one fasting and one after food intake. While within-timepoint and within-day reproducibility were good for single wavelength 800 nm and total hemoglobin (ICC 0.722-0.956), between-day reproducibility was inferior (ICC -0.137 to 0.438). However, temporal variability was smaller than variation between individuals (coefficients of variation 8.9%-33.7% vs. 17.0%-48.5%). After food intake and consecutive increased intestinal circulation, indicated by reduced resistance index of simultaneous Doppler ultrasound, optoacoustic signals did not alter significantly. In summary, this study demonstrates high reliability and temporal stability of MSOT for imaging the human intestine during fasting and after food intake.

4.
Front Surg ; 9: 811126, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35273995

RESUMO

Background: Due to an increasing life expectancy, more and more patients experience the failure of peripheral arterial revascularization. This study aims to investigate patients treated for the failure of infra-inguinal bypass grafts, and to investigate the interaction of different bypass materials [great saphenous vein (GSV) and polytetrafluoroethylene (PTFE)] and the further outcome. Methods: Retrospective single-center analysis of consecutive patients treated for acute or chronic occlusion of infra-inguinal bypasses at a university hospital was conducted. Hospitalizations from 1st January 2010 through 31st December 2019 were included. Perioperative parameters from the index operation including graft material (prosthetic vs. autologous) were assessed. After bypass occlusion, the grade of ischemia, as well as the distal landing zone of the redo bypass compared with the primary bypass was investigated. Results: In this study, 158 (65% men and 35% women with a m mean age of 70.5 years) eligible patients were included (57% vein and 42% prosthetic bypass grafts). After graft occlusion, 47% of the patients presented with symptoms of acute limb-threatening ischemia, 53% with symptoms of chronic leg ischemia. The rate of acute limb-threatening ischemia was significantly higher when prosthetic graft material was used during the index operation (p =0.016). Additionally, in case of reoperation, the landing zone of the redo bypass was significantly more distally located after occlusion of prosthetic bypass graft (p = 0.014). Conclusion: Occlusions of prosthetic bypass grafts were associated with significantly higher rates of acute symptoms compared with vein grafts. Additionally, a shift to a more distal landing zone was recognized after the failure of a prosthetic bypass graft during the redo bypass operation.

5.
J Exp Psychol Hum Percept Perform ; 43(6): 1194-1206, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28383960

RESUMO

There is compelling evidence that context strongly influences our choice of words (e.g., whether we refer to a particular animal with the basic-level name "bird" or the subordinate-level name "duck"). However, little is known about whether the context already affects the degree to which the alternative words are activated. In this study, we explored the effect of a preceding linguistic context on the phonological activation of alternative picture names. In Experiments 1 to 3, the context was established by a request produced by an imaginary interlocutor. These requests either constrained the naming response to the subordinate level on pragmatic grounds (e.g., "name the bird!") or not (e.g., "name the object!"). In Experiment 4, the context was established by the speaker's own previous naming response. Participants named the pictures with their subordinate-level names and the phonological activation of the basic-level names was assessed with distractor words phonologically related versus unrelated to that name (e.g., "birch" vs. "lamp"). In all experiments, we consistently found that distractor words phonologically related to the basic-level name interfered with the naming response more strongly than unrelated distractor words. Moreover, this effect was of comparable size for nonconstraining and constraining contexts indicating that the alternative name was phonologically activated and competed for selection, even when it was not an appropriate lexical option. Our results suggest that the speech production system is limited in its ability of flexibly adjusting and fine-tuning the lexical activation patterns of words (among which to choose from) as a function of pragmatic constraints. (PsycINFO Database Record


Assuntos
Psicolinguística , Comportamento Verbal/fisiologia , Adulto , Feminino , Humanos , Masculino , Fala/fisiologia , Adulto Jovem
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