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1.
Eur J Neurosci ; 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37118877

RESUMO

Pupil size covaries with the diffusion rate of the cholinergic and noradrenergic neurons throughout the brain, which are essential to arousal. Recent findings suggest that slow pupil fluctuations during locomotion are an index of sustained activity in cholinergic axons, whereas phasic dilations are related to the activity of noradrenergic axons. Here, we investigated movement induced arousal (i.e., by singing and swaying to music), hypothesising that actively engaging in musical behaviour will provoke stronger emotional engagement in participants and lead to different qualitative patterns of tonic and phasic pupil activity. A challenge in the analysis of pupil data is the turbulent behaviour of pupil diameter due to exogenous ocular activity commonly encountered during motor tasks and the high variability typically found between individuals. To address this, we developed an algorithm that adaptively estimates and removes pupil responses to ocular events, as well as a functional data methodology, derived from Pfaffs' generalised arousal, that provides a new statistical dimension on how pupil data can be interpreted according to putative neuromodulatory signalling. We found that actively engaging in singing enhanced slow cholinergic-related pupil dilations and having the opportunity to move your body while performing amplified the effect of singing on pupil activity. Phasic pupil oscillations during motor execution attenuated in time, which is often interpreted as a measure of sense of agency over movement.

2.
J Cardiovasc Magn Reson ; 23(1): 136, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34852822

RESUMO

BACKGROUND: Data on the prognostic value of left ventricular (LV) morphological and functional parameters including LV rotation in patients with dilated cardiomyopathy (DCM) using cardiovascular magnetic resonance (CMR) are currently scarce. In this study, we assessed the prognostic value of global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS) and LV torsion using CMR feature tracking (FT). METHODS: CMR was performed in 350 DCM patients and 70 healthy subjects across 5 different European CMR Centers. Myocardial strain parameters were retrospectively assessed from conventional balanced steady-state free precession cine images applying FT. A combined primary endpoint (cardiac death, heart transplantation, aborted sudden cardiac death) was defined for the assessment of clinical outcome. RESULTS: GLS, GCS, GRS and LV torsion were significantly lower in DCM patients than in healthy subjects (all p < 0.001). The primary endpoint occurred in 59 (18.7%) patients [median follow-up 4.2 (2.0-5.6) years]. In the univariate analyses all strain parameters showed a significant prognostic value (p < 0.05). In the multivariate model, LV strain parameters, particularly GLS provided an incremental prognostic value compared to established CMR parameters like LV ejection fraction and late gadolinium enhancement. A scoring model including six categorical variables of standard CMR and strain parameters differentiated further risk subgroups. CONCLUSION: LV strain assessed with CMR FT has a high prognostic value in patients with DCM, surpassing routine and dedicated functional parameters. Thus, CMR strain imaging may contribute to the improvement of risk stratification in DCM.


Assuntos
Cardiomiopatia Dilatada , Cardiomiopatia Dilatada/diagnóstico por imagem , Meios de Contraste , Gadolínio , Humanos , Imagem Cinética por Ressonância Magnética , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
3.
Arch Orthop Trauma Surg ; 140(9): 1285-1291, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32572595

RESUMO

PURPOSE: Coxarthrosis is a common disease of the adult hip joint. Elderly patients have mainly been treated with total hip arthroplasty (THA); however, younger patients are increasingly affected. Short-stem prostheses were developed for this special patient group. There have been few studies on the clinical outcomes of this type of prosthesis. This study compared the mid-term results of a short-stem prosthesis and a standard-stem prosthesis 8 years after implantation. METHODS: According to our clinical registry, patients who received a short-stem prosthesis before 2011 were identified. Patients in the standard-stem prosthesis group were matched based on the sex, age, height, weight, and degree of arthrosis. At the follow-up time, the modified Harris Hip Score (mHHS), University of California Los Angeles (UCLA) activity score and visual analog scale (VAS) pain score were collected and compared with the preoperative values. RESULTS: Fifty-five patients could be matched and analyzed for both groups. No patients needed revision surgery. In both groups, there were significant improvements at the follow-up time. The pre- and postoperative mHHSs, UCLA scores, and VAS scores were 41.9 and 95 (p < 0.0001), 3.75 and 7.9 (p < 0.0001), and 7.6 and 0.9 (p < 0.0001), respectively, in the short-stem group and 44.8 and 96.25 (p < 0.0001), 3.6 and 7.7 (p < 0.0001), and 7.7 and 0.9 (p < 0.0001), respectively, in the control group, with no significant differences between the groups at the follow-up time. CONCLUSION: The short-stem prosthesis provides mid-term results comparable to those of a standard-stem prosthesis. In both groups, excellent patient-reported outcomes were achieved after an average of 8 years. LEVEL OF EVIDENCE: IV.


Assuntos
Artroplastia de Quadril/instrumentação , Prótese de Quadril , Artroplastia de Quadril/métodos , Seguimentos , Articulação do Quadril/cirurgia , Humanos , Desenho de Prótese , Resultado do Tratamento
4.
Radiology ; 283(3): 681-691, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28156200

RESUMO

Purpose To assess the utility of established functional markers versus two additional functional markers derived from standard cardiovascular magnetic resonance (MR) images for their incremental diagnostic and prognostic information in patients with nonischemic dilated cardiomyopathy (NIDCM). Materials and Methods Approval was obtained from the local ethics committee. MR images from 453 patients with NIDCM and 150 healthy control subjects were included between 2005 and 2013 and were analyzed retrospectively. Myocardial contraction fraction (MCF) was calculated by dividing left ventricular (LV) stroke volume by LV myocardial volume, and long-axis strain (LAS) was calculated from the distances between the epicardial border of the LV apex and the midpoint of a line connecting the origins of the mitral valve leaflets at end systole and end diastole. Receiver operating characteristic curve, Kaplan-Meier method, Cox regression, and classification and regression tree (CART) analyses were performed for diagnostic and prognostic performances. Results LAS (area under the receiver operating characteristic curve [AUC] = 0.93, P < .001) and MCF (AUC = 0.92, P < .001) can be used to discriminate patients with NIDCM from age- and sex-matched control subjects. A total of 97 patients reached the combined end point during a median follow-up of 4.8 years. In multivariate Cox regression analysis, only LV ejection fraction (EF) and LAS independently indicated the combined end point (hazard ratio = 2.8 and 1.9, respectively; P < .001 for both). In a risk stratification approach with classification and regression tree analysis, combined LV EF and LAS cutoff values were used to stratify patients into three risk groups (log-rank test, P < .001). Conclusion Cardiovascular MR-derived MCF and LAS serve as reliable diagnostic and prognostic markers in patients with NIDCM. LAS, as a marker for longitudinal contractile function, is an independent parameter for outcome and offers incremental information beyond LV EF and the presence of myocardial fibrosis. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/fisiopatologia , Imageamento por Ressonância Magnética , Contração Miocárdica , Técnicas de Imagem Cardíaca , Cardiomiopatia Dilatada/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
5.
Eur J Nucl Med Mol Imaging ; 44(6): 1025-1032, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28197685

RESUMO

PURPOSE: The role of dopamine D1-type receptor (D1R)-expressing neurons in the regulation of motivated behavior and reward prediction has not yet been fully established. As a prerequisite for future research assessing D1-mediated neuronal network regulation using simultaneous PET/MRI and D1R-selective [11C]SCH23390, this study investigated the stability of central D1R measurements between two independent PET/MRI sessions under baseline conditions. METHODS: Thirteen healthy volunteers (7 female, age 33 ± 13 yrs) underwent 90-min emission scans, each after 90-s bolus injection of 486 ± 16 MBq [11C]SCH23390, on two separate days within 2-4 weeks using a PET/MRI system. Parametric images of D1R distribution volume ratio (DVR) and binding potential (BPND) were generated by a multi-linear reference tissue model with two parameters and the cerebellar cortex as receptor-free reference region. Volume-of-interest (VOI) analysis was performed with manual VOIs drawn on consecutive transverse MRI slices for brain regions with high and low D1R density. RESULTS: The DVR varied from 2.5 ± 0.3 to 2.9 ± 0.5 in regions with high D1R density (e.g. the head of the caudate) and from 1.2 ± 0.1 to 1.6 ± 0.2 in regions with low D1R density (e.g. the prefrontal cortex). The absolute variability of the DVR ranged from 2.4% ± 1.3% to 5.1% ± 5.3%, while Bland-Altman analyses revealed very low differences in mean DVR (e.g. 0.013 ± 0.17 for the nucleus accumbens). Intraclass correlation (one-way, random) indicated very high agreement (0.93 in average) for both DVR and BPND values. Accordingly, the absolute variability of BPND ranged from 7.0% ± 4.7% to 12.5% ± 10.6%; however, there were regions with very low D1R content, such as the occipital cortex, with higher mean variability. CONCLUSION: The test-retest reliability of D1R measurements in this study was very high. This was the case not only for D1R-rich brain areas, but also for regions with low D1R density. These results will provide a solid base for future joint PET/MRI data analyses in stimulation-dependent mapping of D1R-containing neurons and their effects on projections in neuronal circuits that determine behavior.


Assuntos
Imageamento por Ressonância Magnética , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Receptores de Dopamina D1/metabolismo , Adulto , Benzazepinas , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Radioisótopos de Carbono , Feminino , Voluntários Saudáveis , Humanos , Masculino , Reprodutibilidade dos Testes
6.
Eur Radiol ; 27(9): 3913-3923, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28188427

RESUMO

OBJECTIVE: To investigate the association of right ventricular long axis strain (RV-LAS), a parameter of longitudinal function, with outcome in patients with non-ischaemic dilated cardiomyopathy (NIDCM). METHODS: In 441 patients with NIDCM, RV-LAS was analysed retrospectively by measuring the length between the epicardial border of the left ventricular apex and the middle of a line connecting the origins of the tricuspidal valve leaflets in end-diastole and end-systole on non-contrast standard cine sequences. RESULTS: The primary endpoint (cardiac death or heart transplantation) occurred in 41 patients, whereas 95 reached the combined endpoint (including cardiac decompensation and sustained ventricular arrhythmias) during a median follow-up of 4.2 years. Kaplan-Meier survival curves showed a poor outcome in patients with RV-LAS values below -10% (log-rank, p < 0.0001). In a risk stratification model RV-LAS improved prediction of outcome in addition to RV ejection fraction (RVEF) and presence of late gadolinium enhancement. Assessment of RV-LAS offered incremental information compared to clinical symptoms, biomarkers and RVEF. Even in the subgroup with normal RVEF (>45%, n = 213) reduced RV-LAS was still associated with poor outcome. CONCLUSION: Assessment of RV-LAS is an independent indicator of outcome in patients with NIDCM and offers incremental information beyond clinical and cardiac MR parameters. KEY POINTS: • Impaired right ventricular longitudinal function (RV-LAS) is associated with poorer cardiac outcomes. • Poor outcome is associated with decreased RV-LAS even in patients with RVEF >45%. • Addition of RV-LAS to known risk factors enhances the power prognostic information.


Assuntos
Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/mortalidade , Cardiomiopatia Dilatada/cirurgia , Feminino , Gadolínio , Transplante de Coração/mortalidade , Ventrículos do Coração/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Estresse Fisiológico/fisiologia , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/mortalidade
7.
J Cardiovasc Magn Reson ; 19(1): 87, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29121956

RESUMO

BACKGROUND: To compare the prognostic value of cardiac valve plane displacement (CVPD) on various locations in cardiac light chain (AL) amyloidosis. METHODS: Consecutive patients with biopsy-proven cardiac involvement in AL amyloidosis who had undergone cardiovascular magnetic resonance (CMR) between 2005 and 2014 in our institution, were retrospectively identified and data analyzed. The primary combined endpoint was all-cause mortality or heart transplantation. Systolic CVPD were obtained from standard cine bSSFP in 2-, 3- and 4-chamber views at anterior aortic plane systolic excursion (AAPSE); anterior, anterolateral, inferolateral, inferior, inferoseptal mitral (MAPSE); and lateral tricuspid (TAPSE) annular segments. RESULTS: We identified 68 patients (58 ± 10 years; 59% male). Median follow-up period was 1.2 years (IQR, 0.3-4.1). Significant differences in CVPD between patients who reached a primary endpoint (n = 44) and transplant-free survivors were found only for AAPSE (6.1 mm (IQR, 4.6-9.4) vs. 8.8 mm (IQR, 6.9-10.4); p = 0.02) and MAPSEanterolateral (7.3 mm (IQR, 5.4-11.7) vs. 10.5 mm (IQR, 8.1-13.4); p = 0.03). AAPSE (χ2 = 15.6; p = 0.0002) provided the best predictive value for transplant-free survival compared to all other valvular plane locations. A high-risk cutoff (AAPSE ≤ 7.6 mm) was calculated by ROC analysis to predict all-cause death or heart transplantation within 6 months from index examination (AUC = 0.80; CI: 0.68 to 0.89; p < 0.0001). AAPSE added incremental prognostic power to an imaging prediction model of late gadolinium enhancement and global longitudinal strain (GLS) (∆χ2 = 5.8, p = 0.02) as well as to a clinical model including Karnofsky index and NT-proBNP (∆χ2 = 6.2, p = 0.01). CONCLUSION: In patients with cardiac involvement in AL amyloidosis, systolic CVPD obtained from standard long axis cine views appear to indicate outcome better, when obtained in the anterior aortic plane (AAPSE) and provide incremental prognostic value to LGE and strain measurements.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico por imagem , Imageamento por Ressonância Magnética , Contração Miocárdica , Função Ventricular Esquerda , Idoso , Área Sob a Curva , Biópsia , Cardiomiopatias/mortalidade , Cardiomiopatias/fisiopatologia , Cardiomiopatias/cirurgia , Distribuição de Qui-Quadrado , Feminino , Alemanha , Transplante de Coração , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/mortalidade , Amiloidose de Cadeia Leve de Imunoglobulina/fisiopatologia , Amiloidose de Cadeia Leve de Imunoglobulina/cirurgia , Estimativa de Kaplan-Meier , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Tempo
8.
Chemistry ; 22(33): 11578-82, 2016 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-27403892

RESUMO

Synthetic access to multiple surface decorations are a bottleneck in the development of liposomes for receptor mediated targeting. This opens a complex multiparameter space, exploration of which is severely limited in terms of sample numbers and turnaround times. Here, we unlock this technological barrier by a combination of a milligram-scale liposome formulation using dual centrifugation and orthogonal click chemistry on the liposomal surface. Application of these techniques to conceptually new amphiphilic compounds, which feature norbornene and alkyne groups at the apex of sterically stabilizing, hyperbranched polyglycerol moieties, revealed a particular influence of the membrane anchor of functional amphiphiles. Folic acid residues clicked to cholesterol-based amphiphiles were inefficient in folate-mediated cell targeting, while dialkyl-anchored amphiphiles remained stable in the liposomal membrane and imparted efficient targeting properties. These findings are of specific importance considering the popularity of cholesterol as a lipophilic anchor.


Assuntos
Colesterol/química , Ácido Fólico/química , Glicerol/química , Lipídeos/química , Lipossomos/química , Polímeros/química , Colesterol/sangue , Química Click , Humanos
9.
J Cardiovasc Magn Reson ; 18(1): 36, 2016 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-27268238

RESUMO

BACKGROUND: Long axis strain (LAS) has been shown to be a fast assessable parameter representing global left ventricular (LV) longitudinal function in cardiovascular magnetic resonance (CMR). However, the prognostic value of LAS in cardiomyopathies with reduced left ventricular ejection fraction (LVEF) has not been evaluated yet. METHODS AND RESULTS: In 146 subjects with non-ischemic dilated cardiomyopathy (NIDCM, LVEF ≤45 %) LAS was assessed retrospectively from standard non-contrast SSFP cine sequences by measuring the distance between the epicardial border of the left ventricular apex and the midpoint of a line connecting the origins of the mitral valve leaflets in end-systole and end-diastole. The final values were calculated according to the strain formula. The primary endpoint of the study was defined as a combination of cardiac death, heart transplantation or aborted sudden cardiac death and occurred in 24 subjects during follow-up. Patients with LAS values > -5 % showed a significant higher rate of cardiac events independent of the presence of late gadolinium enhancement (LGE). The multivariate Cox regression analysis revealed that LVEDV/BSA (HR: 1.01, p < 0.05), presence of LGE (HR: 2.51, p < 0.05) and LAS (HR: 1.28, p < 0.05) were independent predictors for cardiac events. In a sequential cox regression analysis LAS offered significant incremental information (p < 0.05) for the prediction of outcome in addition to LGE and LVEDV/BSA. Using a dichotomous three point scoring model for risk stratification, including LVEF <35 %, LAS > -10 % and the presence of LGE, patients with 3 points had a significantly higher risk for cardiac events than those with 2 or less points. CONCLUSION: Assessment of long axis function with LAS offers significant incremental information for the prediction of cardiac events in NIDCM and improves risk stratification beyond established CMR parameters.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Adulto , Idoso , Fenômenos Biomecânicos , Cardiomiopatia Dilatada/etiologia , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Dilatada/cirurgia , Distribuição de Qui-Quadrado , Meios de Contraste/administração & dosagem , Morte Súbita Cardíaca/etiologia , Feminino , Transplante de Coração , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Análise Multivariada , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/cirurgia
10.
Brain ; 138(Pt 8): 2438-50, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26041611

RESUMO

Musical memory is considered to be partly independent from other memory systems. In Alzheimer's disease and different types of dementia, musical memory is surprisingly robust, and likewise for brain lesions affecting other kinds of memory. However, the mechanisms and neural substrates of musical memory remain poorly understood. In a group of 32 normal young human subjects (16 male and 16 female, mean age of 28.0 ± 2.2 years), we performed a 7 T functional magnetic resonance imaging study of brain responses to music excerpts that were unknown, recently known (heard an hour before scanning), and long-known. We used multivariate pattern classification to identify brain regions that encode long-term musical memory. The results showed a crucial role for the caudal anterior cingulate and the ventral pre-supplementary motor area in the neural encoding of long-known as compared with recently known and unknown music. In the second part of the study, we analysed data of three essential Alzheimer's disease biomarkers in a region of interest derived from our musical memory findings (caudal anterior cingulate cortex and ventral pre-supplementary motor area) in 20 patients with Alzheimer's disease (10 male and 10 female, mean age of 68.9 ± 9.0 years) and 34 healthy control subjects (14 male and 20 female, mean age of 68.1 ± 7.2 years). Interestingly, the regions identified to encode musical memory corresponded to areas that showed substantially minimal cortical atrophy (as measured with magnetic resonance imaging), and minimal disruption of glucose-metabolism (as measured with (18)F-fluorodeoxyglucose positron emission tomography), as compared to the rest of the brain. However, amyloid-ß deposition (as measured with (18)F-flobetapir positron emission tomography) within the currently observed regions of interest was not substantially less than in the rest of the brain, which suggests that the regions of interest were still in a very early stage of the expected course of biomarker development in these regions (amyloid accumulation → hypometabolism → cortical atrophy) and therefore relatively well preserved. Given the observed overlap of musical memory regions with areas that are relatively spared in Alzheimer's disease, the current findings may thus explain the surprising preservation of musical memory in this neurodegenerative disease.


Assuntos
Doença de Alzheimer/fisiopatologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Memória/fisiologia , Música , Idoso , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Mapeamento Encefálico/métodos , Transtornos Cognitivos/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons/métodos
11.
Macromol Rapid Commun ; 37(1): 60-66, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26480295

RESUMO

In this work, activated ester chemistry is employed to synthesize biocompatible and readily functionalizable polymersomes. Via aminolysis of pentafluorophenyl methacrylate-based precursor polymers, an N-(2-hydroxypropyl) methacrylamide (HPMA)-analog hydrophilic block is obtained. The precursor polymers can be versatile functionalized by simple addition of suitable primary amines during aminolysis as demonstrated using a fluorescent dye. Vesicle formation is proven by cryoTEM and light scattering. High encapsulation efficiencies for hydrophilic cargo like siRNA are achieved using dual centrifugation and safe encapsulation is demonstrated by gel electrophoresis. In vitro studies reveal low cytotoxicity and no protein adsorption-induced aggregation in human blood serum occurs, making the vesicles interesting candidates as nanosized drug carriers.

12.
Proc Natl Acad Sci U S A ; 110(44): 17784-9, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24127588

RESUMO

Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting.


Assuntos
Retroalimentação , Música/psicologia , Esforço Físico/fisiologia , Propriocepção/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicofisiologia , Espirometria
14.
Neuroimage ; 116: 68-79, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25976924

RESUMO

Ventral striatal activity has been previously shown to correspond well to reward value mediated by music. Here, we investigate the dynamic brain response to music and manipulated counterparts using functional magnetic resonance imaging (fMRI). Counterparts of musical excerpts were produced by either manipulating the consonance/dissonance of the musical fragments or playing them backwards (or both). Results show a greater involvement of the ventral striatum/nucleus accumbens both when contrasting listening to music that is perceived as pleasant and listening to a manipulated version perceived as unpleasant (backward dissonant), as well as in a parametric analysis for increasing pleasantness. Notably, both analyses yielded a ventral striatal response that was strongest during an early phase of stimulus presentation. A hippocampal response to the musical stimuli was also observed, and was largely mediated by processing differences between listening to forward and backward music. This hippocampal involvement was again strongest during the early response to the music. Auditory cortex activity was more strongly evoked by the original (pleasant) music compared to its manipulated counterparts, but did not display a similar decline of activation over time as subcortical activity. These findings rather suggest that the ventral striatal/nucleus accumbens response during music listening is strongest in the first seconds and then declines.


Assuntos
Percepção Auditiva/fisiologia , Música/psicologia , Núcleo Accumbens/fisiologia , Estriado Ventral/fisiologia , Estimulação Acústica , Adulto , Córtex Auditivo/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Recompensa , Adulto Jovem
15.
Biomacromolecules ; 15(7): 2440-8, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24805163

RESUMO

Aiming at controlled modification of liposomal surface structures, we describe a postpreparational approach for surface derivatization of a new type of multifunctional, sterically stabilized liposomes. Application of dual centrifugation (DC) resulted in high encapsulation efficiencies above 50% at very small batch sizes with a total volume of 150 µL, which were conductive to fast and efficient optimization of variegated surface modification reactions. Cholesterol-polymer amphiphiles, including complex hyperbranched polyether structures bearing 1-4 terminal alkynes, were used in DC formulations to provide steric stabilization. The alkyne moieties were explored as anchors for the conjugation of small molecules to the liposomal surface via click chemistry, binding 350-450 fluorophores per liposome as examples for surface active molecules. Using Förster resonance energy transfer (FRET) spectroscopy, the conjugation reaction as well as the uptake of FRET-labeled liposomes by RBE4 cells was monitored, and the distribution of the fluorescent lipids among cellular structures and membranes could be studied. Thus, the combination of clickable hyperbranched amphiphiles and dual centrifugation provides access to well-defined liposomal formulations with a variety of surface moieties.


Assuntos
Doxorrubicina/análogos & derivados , Polímeros/farmacologia , Alcinos/química , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Linhagem Celular , Química Click , Doxorrubicina/química , Doxorrubicina/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Transferência Ressonante de Energia de Fluorescência , Lipossomos , Microscopia Confocal , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Polímeros/química , Ratos
16.
J Org Chem ; 79(13): 6269-78, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24931463

RESUMO

Intramolecular halogen bonds between aryl halide donors and suitable acceptors, such as carbonyl or quinolinyl groups, held in proximity by 1,2-aryldiyne linkers, provide triangular structures in the solid state. Aryldiyne linkers provide a nearly ideal template for intramolecular halogen bonding as minor deviations from alkyne linearity can accommodate a variety of halogen bonding interactions, including O···Cl, O···Br, O···I, N···Br, and N···I. Halogen bond lengths for these units, observed by single crystal X-ray crystallography, range from 2.75 to 2.97 Å. Internal bond angles of the semirigid bridge between halogen bond donor and acceptor are responsive to changes in the identity of the halogen, the identity of the acceptor, and the electronic environment around the halogen, with the triangles retaining almost perfect co-planarity in even the most strained systems. Consistency between experimental results and structures predicted by M06-2X/6-31G* calculations demonstrates the efficacy of this computational method for modeling halogen-bonded structures of this type.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38832086

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental condition characterized by patterns of inattention and impulsivity, which lead to difficulties maintaining concentration and motivation while completing academic tasks. University settings, characterized by a high student-to-staff ratio, make treatments relying on human monitoring challenging. One potential replacement is Virtual Reality (VR) technology, which has shown potential to enhance learning outcomes and promote flow experience. In this study, we investigate the usage of VR with 27 university students with ADHD in an effort to improve their performance in ctableompleting homework, including an exploration of automated feedback via a technology probe. Quantitative results show significant increases in concentration, motivation, and effort levels during these VR sessions and qualitative data offers insight into considerations like comfort and deployment. Together, the results suggest that VR can be a valuable tool in leveling the playing field for university students with ADHD.

18.
Neuroimage ; 81: 49-60, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23684870

RESUMO

This study investigates neural correlates of music-evoked fear and joy with fMRI. Studies on neural correlates of music-evoked fear are scant, and there are only a few studies on neural correlates of joy in general. Eighteen individuals listened to excerpts of fear-evoking, joy-evoking, as well as neutral music and rated their own emotional state in terms of valence, arousal, fear, and joy. Results show that BOLD signal intensity increased during joy, and decreased during fear (compared to the neutral condition) in bilateral auditory cortex (AC) and bilateral superficial amygdala (SF). In the right primary somatosensory cortex (area 3b) BOLD signals increased during exposure to fear-evoking music. While emotion-specific activity in AC increased with increasing duration of each trial, SF responded phasically in the beginning of the stimulus, and then SF activity declined. Psychophysiological Interaction (PPI) analysis revealed extensive emotion-specific functional connectivity of AC with insula, cingulate cortex, as well as with visual, and parietal attentional structures. These findings show that the auditory cortex functions as a central hub of an affective-attentional network that is more extensive than previously believed. PPI analyses also showed functional connectivity of SF with AC during the joy condition, taken to reflect that SF is sensitive to social signals with positive valence. During fear music, SF showed functional connectivity with visual cortex and area 7 of the superior parietal lobule, taken to reflect increased visual alertness and an involuntary shift of attention during the perception of auditory signals of danger.


Assuntos
Tonsila do Cerebelo/fisiologia , Córtex Auditivo/fisiologia , Mapeamento Encefálico , Medo/fisiologia , Felicidade , Música/psicologia , Estimulação Acústica , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
19.
Eur J Neurosci ; 38(7): 3099-105, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23859464

RESUMO

Helmholtz himself speculated about a role of the cochlea in the perception of musical dissonance. Here we indirectly investigated this issue, assessing the valence judgment of musical stimuli with variable consonance/dissonance and presented diotically (exactly the same dissonant signal was presented to both ears) or dichotically (a consonant signal was presented to each ear--both consonant signals were rhythmically identical but differed by a semitone in pitch). Differences in brain organisation underlying inter-subject differences in the percept of dichotically presented dissonance were determined with voxel-based morphometry. Behavioral results showed that diotic dissonant stimuli were perceived as more unpleasant than dichotically presented dissonance, indicating that interactions within the cochlea modulated the valence percept during dissonance. However, the behavioral data also suggested that the dissonance percept did not depend crucially on the cochlea, but also occurred as a result of binaural integration when listening to dichotic dissonance. These results also showed substantial between-participant variations in the valence response to dichotic dissonance. These differences were in a voxel-based morphometry analysis related to differences in gray matter density in the inferior colliculus, which strongly substantiated a key role of the inferior colliculus in consonance/dissonance representation in humans.


Assuntos
Percepção Auditiva , Colículos Inferiores/anatomia & histologia , Música , Estimulação Acústica , Adulto , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
20.
Int J Cardiol Heart Vasc ; 46: 101203, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37091914

RESUMO

Background: With 900'000 coronary angiographies (CA) per year, Germany has the highest annual per capita volume in Europe. Until now there are no prospective clinical data on the degree of guideline-adherence in the use of CA in patients with suspected chronic coronary syndrome (CCS) in Germany. Methods: Between January 2019 and August 2021, 458 patients with suspected CCS were recruited in nine German centres. Guideline-adherence was evaluated according to the current European Society of Cardiology and German guidelines. Pre-test probability (PTP) for CAD was determined using age, gender, and a standardized patient questionnaire to identify symptoms. Data on the diagnostic work-up were obtained from health records. Results: Patients were in mean 66.6 years old, male in 57.3 %, had known CAD in 48.4 % and presented with typical, atypical, non-anginal chest pain or dyspnoea in 35.7 %, 41.3 %, 23.0 % and 25.4 %, respectively. PTP according to the European guidelines was in mean 24.2 % (11.9 %-36.5 % 95 % CI). 20.9 % of the patients received guideline-recommended preceding non-invasive image guided testing. The use of CA was adherent to the European and German guideline recommendations in 20.4 % and 25.4 %, respectively. In multivariate-analysis, arterial hypertension and prior revascularization were predictors of guideline non-adherence. Conclusion: These are the first prospective clinical data which demonstrated an overall low degree of guideline-adherence in the use of CA in patients with suspected CCS in the German health care setting. To improve adherence rates, the availability of and access to non-invasive image guided testing needs to be strengthened. (German Clinical Trials Registry DRKS00015638 - Registration Date: 19.02.2019).

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