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1.
Europace ; 26(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38587311

RESUMO

AIMS: Pericardiocentesis is usually completed under fluoroscopy. The electroanatomic mapping (EAM) system allows visualizing puncture needle tip (NT) while displaying the electrogram recorded from NT, making it possible to obtain epicardial access (EA) independent of fluoroscopy. This study was designed to establish and validate a technique by which EA is obtained under guidance of three-dimensional (3D) EAM combined with NT electrogram. METHODS AND RESULTS: 3D shell of the heart was generated, and the NT was made trackable in the EAM system. Unipolar NT electrogram was continuously monitored. Penetration into pericardial sac was determined by an increase in NT potential amplitude and an injury current. A long guidewire of which the tip was also visible in the EAM system was advanced to confirm EA. Epicardial access was successfully obtained without complication in 13 pigs and 22 patients. In the animals, NT potential amplitude was 3.2 ± 1.0 mV when it was located in mediastinum, 5.2 ± 1.6 mV when in contact with fibrous pericardium, and 9.8 ± 2.8 mV after penetrating into pericardial sac (all P ≤ 0.001). In human subjects, it measured 1.54 ± 0.40 mV, 3.61 ± 1.08 mV, and 7.15 ± 2.88 mV, respectively (all P < 0.001). Fluoroscopy time decreased in every 4-5 cases (64 ± 15, 23 ± 17, and 0 s for animals 1-4, 5-8, 9-13, respectively, P = 0.01; 44 ± 23, 31 ± 18, 4±7 s for patients 1-7, 8-14, 15-22, respectively, P < 0.001). In five pigs and seven patients, EA was obtained without X-ray exposure. CONCLUSION: By tracking NT in the 3D EAM system and continuously monitoring the NT electrogram, it is feasible and safe to obtain EA with minimum or no fluoroscopic guidance.


Assuntos
Técnicas Eletrofisiológicas Cardíacas , Mapeamento Epicárdico , Imageamento Tridimensional , Agulhas , Pericárdio , Humanos , Masculino , Feminino , Animais , Pericárdio/diagnóstico por imagem , Pericárdio/cirurgia , Pessoa de Meia-Idade , Imageamento Tridimensional/métodos , Idoso , Técnicas Eletrofisiológicas Cardíacas/instrumentação , Técnicas Eletrofisiológicas Cardíacas/métodos , Mapeamento Epicárdico/métodos , Pericardiocentese/métodos , Punções , Valor Preditivo dos Testes , Adulto , Suínos , Modelos Animais , Potenciais de Ação , Sus scrofa , Fluoroscopia
2.
Cereb Cortex ; 33(22): 11126-11145, 2023 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-37814363

RESUMO

Early auditory deprivation leads to a reorganization of large-scale brain networks involving and extending beyond the auditory system. It has been documented that visuomotor transformation is impaired after early deafness, associated with a hyper-crosstalk between the task-critical frontoparietal network and the default-mode network. However, it remains unknown whether and how the reorganized large-scale brain networks involving the auditory cortex contribute to impaired visuomotor transformation after early deafness. Here, we asked deaf and early hard of hearing participants and normal hearing controls to judge the spatial location of a visual target. Compared with normal hearing controls, the superior temporal gyrus showed significantly increased functional connectivity with the frontoparietal network and the default-mode network in deaf and early hard of hearing participants, specifically during egocentric judgments. However, increased superior temporal gyrus-frontoparietal network and superior temporal gyrus-default-mode network coupling showed antagonistic effects on egocentric judgments. In deaf and early hard of hearing participants, increased superior temporal gyrus-frontoparietal network connectivity was associated with improved egocentric judgments, whereas increased superior temporal gyrus-default-mode network connectivity was associated with deteriorated performance in the egocentric task. Therefore, the data suggest that the auditory cortex exhibits compensatory neuroplasticity (i.e. increased functional connectivity with the task-critical frontoparietal network) to mitigate impaired visuomotor transformation after early auditory deprivation.


Assuntos
Córtex Auditivo , Surdez , Perda Auditiva , Humanos , Córtex Auditivo/diagnóstico por imagem , Mapeamento Encefálico , Encéfalo , Lobo Temporal/diagnóstico por imagem , Imageamento por Ressonância Magnética
3.
J Cogn Neurosci ; 34(11): 2016-2027, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35900867

RESUMO

Recent evidence in healthy participants suggests that a motor subcomponent of working memory (mWM) may exist. We investigated whether this mWM is impaired in patients with a motor-dominant left hemisphere (LH) stroke and apraxia. Furthermore, we hypothesized that a deficient mWM contributes to deficits in motor cognition, that is, apraxia, in LH stroke. The study included 52 patients with LH stroke and 25 age-matched controls. Patients were classified into LH stroke patients with and without apraxia based on deficits in gesture imitation and object use. All participants were examined using the block span test (visuospatial WM), the digit span test (verbal WM), and a novel mWM task. In the latter, participants were presented with static pictures depicting three different actions: actions with objects, meaningless actions, and meaningful actions. In the mWM task, LH stroke patients with apraxia performed worse than age-matched controls. Notably, LH stroke patients with apraxia showed more pronounced mWM deficits than those without apraxia. These results remained significant even after controlling for visuospatial and verbal WM deficits. Regression analyses revealed that LH stroke patients' mWM deficits predicted deficits in imitation. Data provide neuropsychological evidence for a motor subsystem of WM and suggest that deficits in mWM contribute to the severity of apraxia in LH stroke patients.


Assuntos
Apraxias , Acidente Vascular Cerebral , Apraxias/etiologia , Apraxias/psicologia , Humanos , Comportamento Imitativo , Memória de Curto Prazo , Testes Neuropsicológicos , Acidente Vascular Cerebral/complicações
4.
Curr Opin Cardiol ; 37(1): 10-14, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34698668

RESUMO

PURPOSE OF REVIEW: This review aims to summarize the nonthromboembolic prevention effects of left atrial appendage exclusion (LAAE). RECENT FINDINGS: Left atrial appendage (LAA) secretes multiple hormones; regulates blood volume and pressure; and generates trigger activities. Exclusion of the LAA by different techniques may lead to downstream effects including changes in blood pressure and cardiac performance, improvement of outcome of atrial fibrillation (AF) ablation, and alteration of metabolism. SUMMARY: LAAE procedures not only prevent thromboembolic events in patients with AF, but rather may bring additional benefits or side-effect to patients undergoing LAAE.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Ablação por Cateter , Tromboembolia , Apêndice Atrial/cirurgia , Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Humanos , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Tromboembolia/cirurgia , Resultado do Tratamento
5.
Sensors (Basel) ; 21(11)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072452

RESUMO

Mechatronic and soft robotics are taking inspiration from the animal kingdom to create new high-performance robots. Here, we focused on marine biomimetic research and used innovative bibliographic statistics tools, to highlight established and emerging knowledge domains. A total of 6980 scientific publications retrieved from the Scopus database (1950-2020), evidencing a sharp research increase in 2003-2004. Clustering analysis of countries collaborations showed two major Asian-North America and European clusters. Three significant areas appeared: (i) energy provision, whose advancement mainly relies on microbial fuel cells, (ii) biomaterials for not yet fully operational soft-robotic solutions; and finally (iii), design and control, chiefly oriented to locomotor designs. In this scenario, marine biomimicking robotics still lacks solutions for the long-lasting energy provision, which presently hinders operation autonomy. In the research environment, identifying natural processes by which living organisms obtain energy is thus urgent to sustain energy-demanding tasks while, at the same time, the natural designs must increasingly inform to optimize energy consumption.

6.
Hum Brain Mapp ; 39(9): 3473-3486, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29700893

RESUMO

Evidence from neuropsychological and imaging studies indicate that action and semantic knowledge about tools draw upon distinct neural substrates, but little is known about the underlying interregional effective connectivity. With fMRI and dynamic causal modeling (DCM) we investigated effective connectivity in the left-hemisphere (LH) while subjects performed (i) a function knowledge and (ii) a value knowledge task, both addressing semantic tool knowledge, and (iii) a manipulation (action) knowledge task. Overall, the results indicate crosstalk between action nodes and semantic nodes. Interestingly, effective connectivity was weakened between semantic nodes and action nodes during the manipulation task. Furthermore, pronounced modulations of effective connectivity within the fronto-parietal action system of the LH (comprising lateral occipito-temporal cortex, intraparietal sulcus, supramarginal gyrus, inferior frontal gyrus) were observed in a bidirectional manner during the processing of action knowledge. In contrast, the function and value knowledge tasks resulted in a significant strengthening of the effective connectivity between visual cortex and fusiform gyrus. Importantly, this modulation was present in both semantic tasks, indicating that processing different aspects of semantic knowledge about tools evokes similar effective connectivity patterns. Data revealed that interregional effective connectivity during the processing of tool knowledge occurred in a bidirectional manner with a weakening of connectivity between areas engaged in action and semantic knowledge about tools during the processing of action knowledge. Moreover, different semantic tool knowledge tasks elicited similar effective connectivity patterns.


Assuntos
Córtex Cerebral/fisiologia , Conectoma , Dominância Cerebral/fisiologia , Rede Nervosa/fisiologia , Desempenho Psicomotor/fisiologia , Semântica , Comportamento de Utilização de Ferramentas/fisiologia , Adolescente , Adulto , Equipamentos e Provisões/economia , Feminino , Mãos/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
7.
Neuroimage ; 152: 517-529, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28284803

RESUMO

With increasing age, cognitive control processes steadily decline. Prior research suggests that healthy older adults have a generally intact performance monitoring system, but show specific deficits in error awareness, i.e., the ability to detect committed errors. We examined the neural processing of errors across the adult lifespan (69 participants; age range 20-72 years) by analysing the error (-related) negativity (Ne/ERN) and the error positivity (Pe) using an adapted version of the Go/Nogo task. At a stable overall error rate, higher age was associated with a greater proportion of undetected errors. While the Ne/ERN was associated with the processing of errors in general, the Pe amplitude was modulated by detected errors only. Furthermore, the Pe amplitude for detected errors was significantly smaller in older adults, in contrast to the Ne/ERN amplitude which did not show age-related changes. Structural path models suggested that through those age-related changes in Pe amplitude, an indirect effect on the performance was observed. Our results confirm and extend previous extreme-group based findings about specific deficits in error detection associated with higher age using age as a continuous predictor. Age-related reductions in Pe amplitude, associated with more undetected errors, are independent of early error processing, as evidenced by the preserved Ne/ERN.


Assuntos
Envelhecimento , Córtex Cerebral/fisiologia , Potenciais Evocados , Desempenho Psicomotor , Adulto , Idoso , Eletroencefalografia , Feminino , Humanos , Masculino , Processos Mentais/fisiologia , Pessoa de Meia-Idade , Tempo de Reação , Adulto Jovem
8.
Neuroimage ; 161: 94-103, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28822751

RESUMO

Past attempts to identify the neural substrates of hand and finger imitation skills in the left hemisphere of the brain have yielded inconsistent results. Here, we analyse those associations in a large sample of 257 left hemisphere stroke patients. By introducing novel Bayesian methods, we characterise lesion symptom associations at three levels: the voxel-level, the single-region level (using anatomically defined regions), and the region-pair level. The results are inconsistent across those three levels and we argue that each level of analysis makes assumptions which constrain the results it can produce. Regardless of the inconsistencies across levels, and contrary to past studies which implicated differential neural substrates for hand and finger imitation, we find no consistent voxels or regions, where damage affects one imitation skill and not the other, at any of the three analysis levels. Our novel Bayesian approach indicates that any apparent differences appear to be driven by an increased sensitivity of hand imitation skills to lesions that also impair finger imitation. In our analyses, the results of the highest level of analysis (region-pairs) emphasise a role of the primary somatosensory and motor cortices, and the occipital lobe in imitation. We argue that this emphasis supports an account of both imitation tasks based on direct sensor-motor connections, which throws doubt on past accounts which imply the need for an intermediate (e.g. body-part-coding) system of representation.


Assuntos
Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Gestos , Mãos/fisiopatologia , Comportamento Imitativo/fisiologia , Modelos Teóricos , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Teorema de Bayes , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagem
9.
Cereb Cortex ; 26(1): 440-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26534907

RESUMO

The human brain readily perceives fluent movement from static input. Using functional magnetic resonance imaging, we investigated brain mechanisms that mediate fluent apparent biological motion (ABM) perception from sequences of body postures. We presented body and nonbody stimuli varying in objective sequence duration and fluency of apparent movement. Three body postures were ordered to produce a fluent (ABC) or a nonfluent (ACB) apparent movement. This enabled us to identify brain areas involved in the perceptual reconstruction of body movement from identical lower-level static input. Participants judged the duration of a rectangle containing body/nonbody sequences, as an implicit measure of movement fluency. For body stimuli, fluent apparent motion sequences produced subjectively longer durations than nonfluent sequences of the same objective duration. This difference was reduced for nonbody stimuli. This body-specific bias in duration perception was associated with increased blood oxygen level-dependent responses in the primary (M1) and supplementary motor areas. Moreover, fluent ABM was associated with increased functional connectivity between M1/SMA and right fusiform body area. We show that perceptual reconstruction of fluent movement from static body postures does not merely enlist areas traditionally associated with visual body processing, but involves cooperative recruitment of motor areas, consistent with a "motor way of seeing".


Assuntos
Mapeamento Encefálico , Percepção de Movimento/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Postura/fisiologia , Adulto Jovem
10.
Lasers Surg Med ; 49(10): 882-885, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28881431

RESUMO

OBJECTIVES: The purpose of this study is to assess patient's satisfaction treatment outcomes and out-of-pocket expense for the fractional CO2 laser (SmartXide) in the treatment of genitourinary symptoms of menopause (GSM). MATERIALS AND METHODS: A multicenter retrospective cohort study of patients who completed a course of three vaginal treatments with the SmartXide11 Fractional CO2 laser. Patients contacted via telephone and asked to participate in questionnaires to evaluate for adverse outcomes since last treatment, symptom severity before and after treatment, patient satisfaction with treatment, patient satisfaction with out-of-pocket expense, and sexual function. RESULTS: Of the 368 patients contacted, 122 agreed to be interviewed. No patients reported seeking emergent medical treatment. Patient reported vaginal dryness significantly improved following treatment (P < 0.05). The frequency of intercourse increased from "once a month" to "few times a month" (P < 0.001). The vast majority of patients reported being satisfied with their treatment results (86%) and with the cost of treatment (78%). Satisfaction with the out-of-pocket expense did not correlate with household income (P = 0.07). CONCLUSION: The SmartXide Fractional CO2 laser is a safe and efficacious treatment for GSM. This treatment is associated with a high level of patient satisfaction with both treatment results and out-of-pocket expense. Lasers Surg. Med. 49:882-885, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Dispareunia/cirurgia , Gastos em Saúde , Lasers de Gás/uso terapêutico , Menopausa , Vagina/cirurgia , Doenças Vaginais/cirurgia , Idoso , Dispareunia/economia , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Retrospectivos , Síndrome , Resultado do Tratamento , Estados Unidos , Doenças Vaginais/economia
11.
J Cogn Neurosci ; 28(2): 223-36, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26439271

RESUMO

During rehabilitation after stroke motor sequence learning is of particular importance because considerable effort is devoted to (re)acquiring lost motor skills. Previous studies suggest that implicit motor sequence learning is preserved in stroke patients but were restricted to the spatial dimension, although the timing of single action components is as important as their spatial order. As the left parietal cortex is known to play a critical role in implicit timing and spatiotemporal integration, in this study we applied an adapted version of the SRT task designed to assess both spatial (different stimulus locations) and temporal (different response-stimulus intervals) aspects of motor learning to 24 right-handed patients with a single left-hemisphere (LH) stroke and 24 age-matched healthy controls. Implicit retrieval of sequence knowledge was tested both at Day 1 and after 24 hr (Day 2). Additionally, voxel-based lesion symptom mapping was used to investigate the neurobiological substrates of the behavioral effects. Although LH stroke patients showed a combined spatiotemporal learning effect that was comparable to that observed in controls, LH stroke patients did not show learning effects for the learning probes in which only one type of sequence information was maintained whereas the other one was randomized. Particularly on Day 2, patients showed significantly smaller learning scores for these two learning probes than controls. Voxel-based lesion symptom mapping analyses revealed for all learning probes that diminished learning scores on Day 2 were associated with lesions of the striatum. This might be attributed to its role in motor chunking and offline consolidation as group differences occurred on Day 2 only. The current results suggest that LH stroke patients rely on multimodal information (here: temporal and spatial information) when retrieving motor sequence knowledge and are very sensitive to any disruption of the learnt sequence information as they seem to build very rigid chunks preventing them from forming independent spatial and temporal sequence representations.


Assuntos
Encéfalo/patologia , Aprendizagem , Destreza Motora , Acidente Vascular Cerebral/patologia , Braço/fisiopatologia , Feminino , Lateralidade Funcional , Humanos , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Masculino , Rememoração Mental/fisiologia , Pessoa de Meia-Idade , Destreza Motora/fisiologia , Testes Neuropsicológicos , Tempo de Reação , Índice de Gravidade de Doença , Acidente Vascular Cerebral/fisiopatologia , Reabilitação do Acidente Vascular Cerebral , Percepção do Tempo/fisiologia , Tomografia Computadorizada por Raios X
12.
Mov Disord ; 30(8): 1121-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25914247

RESUMO

BACKGROUND: Subthalamic deep brain stimulation (STN-DBS) can ameliorate gait disturbances in Parkinson's disease (PD). Using motor imagery and positron emission tomography (PET), we investigated how STN-DBS interacts with supraspinal locomotor centers in PD. METHODS: Ten PD patients with bilateral STN-DBS actually walked or stood still under STN-DBS ON or OFF conditions. Directly thereafter, subjects imagined walking or standing while changes in regional cerebral blood flow were measured by PET. RESULTS: Independent of STN-DBS, imagined walking distance correlated with imagery duration. Compared with STN-DBS OFF, STN-DBS ON improved actual gait and increased imagined walking distance. Imagery of gait (vs. stance) induced activity in the supplementary motor area and the right superior parietal lobule for both STN-DBS conditions. The improvement of imagined gait during STN-DBS ON led to activity changes in the pedunculopontine nucleus/mesencephalic locomotor region (PPN/MLR). CONCLUSIONS: Data suggest that STN-DBS improves Parkinsonian gait by modulating PPN/MLR activity.


Assuntos
Estimulação Encefálica Profunda/métodos , Transtornos Neurológicos da Marcha/terapia , Doença de Parkinson/terapia , Núcleo Tegmental Pedunculopontino/fisiopatologia , Núcleo Subtalâmico , Transtornos Neurológicos da Marcha/etiologia , Humanos , Imaginação/fisiologia , Doença de Parkinson/complicações , Tomografia por Emissão de Pósitrons , Núcleo Subtalâmico/cirurgia , Caminhada/fisiologia
13.
J Neurosci ; 33(49): 19205-11, 2013 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-24305816

RESUMO

Gesture processing deficits constitute a key symptom of apraxia, a disorder of motor cognition frequently observed after left-hemispheric stroke. The clinical relevance of apraxia stands in stark contrast to the paucity of therapeutic options available. Transcranial direct current stimulation (tDCS) is a promising tool for modulating disturbed network function after stroke. Here, we investigate the effect of parietal tDCS on gesture processing in healthy human subjects. Neuropsychological and imaging studies suggest that the imitation and matching of hand gestures involve the left inferior parietal lobe (IPL). Using neuronavigation based on cytoarchitectonically defined anatomical probability maps, tDCS was applied over left IPL-areas PF, PFm, or PG in healthy participants (n = 26). Before and after tDCS, subjects performed a gesture matching task and a person discrimination task for control. Changes in error rates and reaction times were analyzed for the effects of anodal and cathodal tDCS (compared with sham tDCS). Matching of hand gestures was specifically facilitated by anodal tDCS applied over the cytoarchitectonically defined IPL-area PFm, whereas tDCS over IPL-areas PF and PG did not elucidate significant effects. Taking into account tDCS electrode size and the central position of area PFm within IPL, it can be assumed that the observed effect is rather the result of a combined stimulation of the supramarginal and angular gyrus than an isolated PFm stimulation. Our data confirm the pivotal role of the left IPL in gesture processing. Furthermore, anatomically guided tDCS of the left IPL may constitute a promising approach to neurorehabilitation of apraxic patients with gesture processing deficits.


Assuntos
Estimulação Elétrica/métodos , Gestos , Comunicação não Verbal/fisiologia , Lobo Parietal/fisiologia , Adulto , Mapeamento Encefálico , Interpretação Estatística de Dados , Discriminação Psicológica/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuronavegação , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
14.
J Cogn Neurosci ; 26(8): 1871-82, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24564459

RESUMO

A moon near to the horizon is perceived larger than a moon at the zenith, although--obviously--the moon does not change its size. In this study, the neural mechanisms underlying the "moon illusion" were investigated using a virtual 3-D environment and fMRI. Illusory perception of an increased moon size was associated with increased neural activity in ventral visual pathway areas including the lingual and fusiform gyri. The functional role of these areas was further explored in a second experiment. Left V3v was found to be involved in integrating retinal size and distance information, thus indicating that the brain regions that dynamically integrate retinal size and distance play a key role in generating the moon illusion.


Assuntos
Percepção de Distância/fisiologia , Ilusões Ópticas/fisiologia , Percepção de Tamanho/fisiologia , Lobo Temporal/fisiologia , Vias Visuais/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Lua , Adulto Jovem
15.
Catheter Cardiovasc Interv ; 84(7): E61-4, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25044542

RESUMO

We report the successful biopsy of a right atrial fatty mass using CARTO 3-dimensional electro-anatomic mapping fused with cardiac MRI. Fluoroscopic guidance within the cardiac chambers lacks precision and therefore risks geographical miss of the intended target and cardiac perforation. CARTO mapping fused with cardiac MRI facilitated precise navigation of the bioptome thereby ensuring a successful biopsy of the intended tissue while minimizing the risks of inadvertent trauma to adjacent tissue.


Assuntos
Biópsia/métodos , Técnicas de Imagem Cardíaca/métodos , Diagnóstico por Computador/métodos , Cardiopatias/diagnóstico , Lipomatose/diagnóstico , Imagem Multimodal/métodos , Idoso , Septo Interatrial , Mapeamento Potencial de Superfície Corporal , Diagnóstico Diferencial , Feminino , Humanos , Imageamento Tridimensional , Imagem Cinética por Ressonância Magnética , Tomografia Computadorizada por Raios X
16.
Appl Opt ; 53(4): A334-8, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24514236

RESUMO

Standard antireflective coatings applied to hard substrates like sapphire suffer from poor abrasion resistance. Silica is used as low refractive index layer in many multilayer systems although it has a lower hardness than the substrate. In this work an attempt was made to enhance the hardness by the addition of alumina. Magnetron sputtering was used in two different ways because it delivers dense coatings with high durability. Nanoindention hardness measurements of mixed alumina-silica films are presented in comparison to haze measurements after a sand trickling test. The hardness of silica is unexpectedly lowered by the addition of small amounts of alumina. Two different stacks were coated in which the low refractive index layers were sputtered as pure material and material mixtures. The thickness loss results after an oscillation abrasion test are presented.

17.
Front Psychiatry ; 15: 1288674, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645414

RESUMO

Background: Alterations in the experience of controlling oneself and one's environment are of high relevance to understanding the psychopathology of depression. This study investigated the relationship between Temporal Binding for action-event sequences, sense of agency, self-efficacy and symptom severity in Major Depressive Disorder. Method: We employed the Sense of Agency Scale (SoAS) and the General Self-Efficacy Scale (GSE) to assess explicit Sense of Agency and self-efficacy in a group of 42 persons diagnosed with Major Depressive Disorder (MDD) [20 identifying as female, 19 as male; mean age 37.8 years (± 13.3)] and 40 control persons without a psychiatric diagnosis (CG) [22 identifying as female, 20 as male; mean age 38.0 years ( ± 13.3)]. Depressive symptom severity was measured using the BDI-II. We additionally performed a temporal binding paradigm as a potential correlate to Sense of Agency. Participants partook in a time estimation task judging three intervals (250ms, 450ms, 650ms) while either observing or causing stimulus presentations. The underestimation of intervals following intentional actions causing stimulus presentations (compared to merely observing the stimulus presentation) is interpreted as temporal binding. Results: SoAS scores demonstrated an inverse correlation with depressive symptoms (CG: p=.032, R2=.113; MDD: p<.001, R2=.260) and a positive correlation with GSE scores (CG: p<.001, R2=.379; MDD: p<.001, R2=.254). We found distinct differences in temporal binding between healthy participants and the Major Depressive Disorder group without significant correlation between temporal binding and the SoAS or GSE scores. The data suggest group differences in time estimation particular pertaining to time intervals involving intentional action and increasingly complex multisensory stimuli. Discussion: We investigated parameters of subjective control, namely Sense of Agency and Self Efficacy. Here, we were able to reveal their inverse relationship with depressive symptoms in patients with major depressive disorder, highlighting a profound experience of loss of control with increasing symptom load. Deficits in experiencing control, particularly involving intentional motor actions (and more complex multisensory stimuli), appear to be more pronounced in Major Depressive Disorder, involving not only negative self-efficacy expectations but also an altered Sense of Agency and temporal binding. Temporal binding and SoAS scores did not correlate, adding to the growing evidence that the two measures may not be directly related. We propose that future research be directed at this contiguous relationship between Sense of Agency and Self Efficacy in Major Depressive Disorder.

18.
Front Aging Neurosci ; 16: 1368052, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38813530

RESUMO

Age-related motor impairments often cause caregiver dependency or even hospitalization. However, comprehensive investigations of the different motor abilities and the changes thereof across the adult lifespan remain sparse. We, therefore, extensively assessed essential basic and complex motor functions in 444 healthy adults covering a wide age range (range 21 to 88 years). Basic motor functions, here defined as simple isolated single or repetitive movements in one direction, were assessed by means of maximum grip strength (GS) and maximum finger-tapping frequency (FTF). Complex motor functions, comprising composite sequential movements involving both proximal and distal joints/muscle groups, were evaluated with the Action Research Arm Test (ARAT), the Jebsen-Taylor Hand Function Test (JTT), and the Purdue Pegboard Test. Men achieved higher scores than women concerning GS and FTF, whereas women stacked more pins per time than men during the Purdue Pegboard Test. There was no significant sex effect regarding JTT. We observed a significant but task-specific reduction of basic and complex motor performance scores across the adult lifespan. Linear regression analyses significantly predicted the participants' ages based on motor performance scores (R2 = 0.502). Of note, the ratio between the left- and right-hand performance remained stable across ages for all tests. Principal Component Analysis (PCA) revealed three motor components across all tests that represented dexterity, force, and speed. These components were consistently present in young (21-40 years), middle-aged (41-60 years), and older (61-88 years) adults, as well as in women and men. Based on the three motor components, K-means clustering analysis differentiated high- and low-performing participants across the adult life span. The rich motor data set of 444 healthy participants revealed age- and sex-dependent changes in essential basic and complex motor functions. Notably, the comprehensive assessment allowed for generating robust motor components across the adult lifespan. Our data may serve as a reference for future studies of healthy subjects and patients with motor deficits. Moreover, these findings emphasize the importance of comprehensively assessing different motor functions, including dexterity, force, and speed, to characterize human motor abilities and their age-related decline.

19.
Neurol Res Pract ; 6(1): 8, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38326916

RESUMO

BACKGROUND: While subthalamic nucleus deep brain stimulation (STN-DBS) improves the quality of life (QoL) of patients with Parkinson's disease (PD), the clinical parameters that predict this improvement remain debated. This retrospective study explored whether preoperative motor, cognitive, and affective parameters predict QoL or its components at 6 and 12 months after STN-DBS surgery. METHODS: QoL was assessed with the Parkinson's Disease Questionnaire-39 (PDQ-39) before (baseline), at 6 months (N = 90) and 12 months (N = 63) after STN-DBS surgery. Changes in the PDQ-39 and its subdomains were analysed with Wilcoxon signed-rank tests. In total, seven motor, cognitive, and affective parameters recorded at baseline were used in multiple linear regressions to predict QoL and its subdomains. RESULTS: QoL had improved significantly at six months post STN-DBS surgery. After 12 months, this effect remained significant but was less pronounced. At both time points, significant improvements in mobility, activities of daily living, stigma, and bodily discomfort were present. Correlation and linear regression analyses showed that preoperative QoL status and changes in QoL at 6 and 12 months after surgery were driven by preoperative dopaminergic medication, as well as motor (UPDRS-III medOFF and PIGD-subscore medOFF) and affective (HADS anxiety and depression) symptoms. In contrast, preoperative cognitive performance did not predict QoL at any time point. CONCLUSION: Data show that preoperative motor and affective symptoms drive both QoL baseline status and changes in QoL after STN-DBS surgery. Thus, these clinical parameters need to be assessed appropriately to provide comprehensive presurgical advice to patients suffering from PD.

20.
eNeuro ; 11(1)2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38164539

RESUMO

Stereotypical isocortical tau protein pathology along the Braak stages has been described as an instigator of neurodegeneration in Alzheimer's disease (AD). Less is known about tau pathology in motor regions, although higher-order motor deficits such as praxis dysfunction are part of the clinical description. Here, we examined how tau pathology in cytoarchitectonically mapped regions of the primary and higher-order motor network in comparison to primary visual and sensory regions varies across the clinical spectrum of AD. We analyzed tau PET scans from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort in patients with mild cognitive impairment (MCI; N = 84) and dementia of the Alzheimer's disease type (DAD; N = 25). Additionally, an amyloid-negative sample of healthy older individuals (HC; N = 26) were included. Standard uptake ratio values (SUVRs) were extracted in native space from the left and the right hemispheres. A repeated measurement analysis of variance was conducted to assess the effect of diagnostic disease category on tau pathology in the individual motor regions, controlling for age. We observed that tau pathology varies as a function of diagnostic category in predominantly higher motor regions (i.e., supplementary motor area, superior parietal lobe, angular gyrus, and dorsal premotor cortex) compared to primary visual, sensory and motor regions. Indeed, tau in higher-order motor regions was significantly associated with decline in cognitive function. Together, these results expand our knowledge on the in vivo pattern of tau pathology in AD and suggest that higher motor regions are not spared from tau aggregation in the course of disease, potentially contributing to the symptomatic appearance of the disease.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/patologia , Proteínas tau/metabolismo , Neuroimagem , Tomografia por Emissão de Pósitrons/métodos , Disfunção Cognitiva/metabolismo , Peptídeos beta-Amiloides/metabolismo
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