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1.
J Parkinsons Dis ; 14(4): 833-842, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38728202

RESUMO

Background: Previous studies have demonstrated the importance of the locus coeruleus (LC) in sleep-wake regulation. Both essential tremor (ET) and Parkinson's disease (PD) share common sleep disorders, such as poor quality of sleep (QoS). LC pathology is a feature of both diseases. A question arises regarding the contribution of LC degeneration to the occurrence of poor QoS. Objective: To evaluate the association between LC impairment and sleep disorders in ET and PD patients. Methods: A total of 83 patients with ET, 124 with PD, and 83 healthy individuals were recruited and divided into ET/PD with/without poor QoS (Sle/NorET and Sle/NorPD) subgroups according to individual Pittsburgh Sleep Quality Index (PSQI) score. Neuromelanin-sensitive magnetic resonance imaging (NM-MRI) and free-water imaging derived from diffusion MRI were performed. Subsequently, we evaluated the association between contrast-to-noise ratio of LC (CNRLC) and free-water value of LC (FWLC) with PSQI scores in ET and PD groups. Results: CNRLC was significantly lower in ET (p = 0.047) and PD (p = 0.018) than in healthy individuals, whereas no significant difference was found in FWLC among the groups. No significant differences were observed in CNR/FWLC between patients with/without sleep disorders after multiple comparison correction. No correlation was identified between CNR/FWLC and PSQI in ET and PD patients. Conclusions: LC degeneration was observed in both ET and PD patients, implicating its involvement in the pathophysiology of both diseases. Additionally, no significant association was observed between LC integrity and PSQI, suggesting that LC impairment might not directly relate to overall QoS.


Assuntos
Tremor Essencial , Locus Cerúleo , Doença de Parkinson , Transtornos do Sono-Vigília , Humanos , Tremor Essencial/fisiopatologia , Tremor Essencial/complicações , Tremor Essencial/patologia , Locus Cerúleo/diagnóstico por imagem , Locus Cerúleo/patologia , Feminino , Masculino , Doença de Parkinson/complicações , Doença de Parkinson/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Idoso , Pessoa de Meia-Idade , Transtornos do Sono-Vigília/etiologia , Transtornos do Sono-Vigília/fisiopatologia , Imageamento por Ressonância Magnética , Degeneração Neural/patologia , Qualidade do Sono , Melaninas
2.
J Mech Behav Biomed Mater ; 156: 106603, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38815434

RESUMO

OBJECTIVES: The objective of this investigation was to assess the stress and displacement pattern of the craniomandibular complex by employing finite element methodology to simulate diverse angulations of inclined planes that are incorporated in the Twin Block appliance. METHODS: A 3D finite element representation was established by use of Cone Beam Computed Tomography (CBCT) scans. This comprehensive structure included craniofacial skeletal components, the articular disc, a posterior disc elastic layer, dental elements, periodontal ligaments, and a Twin Block appliance. This investigation is the first to incorporated inclined planes featuring three distinct angulations (45, 60, and 70°) as the study models. Mechanical impacts were evaluated within the glenoid fossa, tooth, condylar, and articular disc regions. RESULTS: In all simulations, the stress generated by the Twin Block appliance was distributed across teeth and periodontal ligament, facilitating the anterior movement of mandibular teeth and the posterior displacement of maxillary teeth. Within the temporomandibular joint region, compressive forces on the superior and posterior facets of the condyle diminished, coinciding with the stress configuration that fosters condylar and mandibular growth. Stress dispersion homogenized in the condylar anterior facet and articular disc, with considerable tensile stress in the glenoid fossa's posterior aspect conforming to stress distribution that promote fossa reconfiguration. The 70° inclined plane exerts the highest force on the tissues. The condyle's maximum and minimum principal stresses are 0.36 MPa and -0.15 MPa, respectively, while those of the glenoid fossa are 0.54 MPa and -0.23 MPa. CONCLUSION: Three angled appliances serve the purpose of advancing the mandible. A 45° inclined plane relative to the occlusal plane exerts balanced anteroposterior and vertical forces on the mandibular arch. Steeper angles yield greater horizontal forces, which may enhance forward growth and efficient repositioning.


Assuntos
Análise de Elementos Finitos , Estresse Mecânico , Fenômenos Biomecânicos , Mandíbula/fisiologia , Articulação Temporomandibular/diagnóstico por imagem , Articulação Temporomandibular/fisiologia , Humanos , Testes Mecânicos , Tomografia Computadorizada de Feixe Cônico
4.
Neurobiol Dis ; 194: 106472, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479482

RESUMO

BACKGROUND: Whether there is hypothalamic degeneration in Parkinson's disease (PD) and its association with clinical symptoms and pathophysiological changes remains controversial. OBJECTIVES: We aimed to quantify microstructural changes in hypothalamus using a novel deep learning-based tool in patients with PD and those with probable rapid-eye-movement sleep behavior disorder (pRBD). We further assessed whether these microstructural changes associated with clinical symptoms and free thyroxine (FT4) levels. METHODS: This study included 186 PD, 67 pRBD, and 179 healthy controls. Multi-shell diffusion MRI were scanned and mean kurtosis (MK) in hypothalamic subunits were calculated. Participants were assessed using Unified Parkinson's Disease Rating Scale (UPDRS), RBD Questionnaire-Hong Kong (RBDQ-HK), Hamilton Depression Rating Scale (HAMD), and Activity of Daily Living (ADL) Scale. Additionally, a subgroup of PD (n = 31) underwent assessment of FT4. RESULTS: PD showed significant decreases of MK in anterior-superior (a-sHyp), anterior-inferior (a-iHyp), superior tubular (supTub), and inferior tubular hypothalamus when compared with healthy controls. Similarly, pRBD exhibited decreases of MK in a-iHyp and supTub. In PD group, MK in above four subunits were significantly correlated with UPDRS-I, HAMD, and ADL. Moreover, MK in a-iHyp and a-sHyp were significantly correlated with FT4 level. In pRBD group, correlations were observed between MK in a-iHyp and UPDRS-I. CONCLUSIONS: Our study reveals that microstructural changes in the hypothalamus are already significant at the early neurodegenerative stage. These changes are associated with emotional alterations, daily activity levels, and thyroid hormone levels.


Assuntos
Doença de Parkinson , Pindolol/análogos & derivados , Transtorno do Comportamento do Sono REM , Humanos , Doença de Parkinson/complicações , Inquéritos e Questionários
5.
Parkinsonism Relat Disord ; 123: 106559, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38513448

RESUMO

BACKGROUND: Rest tremor is a movement disorder commonly found in diseases like Parkinson's disease (PD) and essential tremor (ET). Rest tremor typically shows slower progression in PD, but more severe progression in ET. However, the underlying white matter organization of rest tremor behind PD and ET remains unclear. METHODS: This study included 57 ET patients (40 without rest tremor (ETWR), 17 with rest tremor (ETRT)), 68 PD patients (34 without rest tremor (PDWR), 34 with rest tremor (PDRT)), and 62 normal controls (NC). Fixel-based analysis was used to evaluate the structural changes of white matter in rest tremor in these different diseases. RESULTS: The fiber-bundle cross-section (FC) of the right non-decussating dentato-rubro-thalamic tract and several fibers outside the dentato-rubro-thalamic pathway in ETWR were significantly higher than that in NC. The fiber density and cross-section of the left nigro-pallidal in PDWR is significantly lower than that in NC, while the FC of bilateral nigro-pallidal in PDRT is significantly lower than that in NC. CONCLUSION: ET patients with pure action tremor showed over-activation of fiber tracts. However, when superimposed with rest tremor, ET patients no longer exhibited over-activation of fiber tracts, but rather showed a trend of fiber tract damage. Except for the nigro-pallidal degeneration in all PD, PDRT will not experience further deterioration in fiber organization. These results provide important insights into the unique effects of rest tremor on brain fiber architecture in ET and PD.


Assuntos
Tremor Essencial , Doença de Parkinson , Tremor , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Tremor Essencial/patologia , Tremor Essencial/fisiopatologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Tremor/etiologia , Tremor/fisiopatologia , Tremor/patologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Substância Branca/patologia , Substância Branca/diagnóstico por imagem , Imageamento por Ressonância Magnética
6.
Neurobiol Dis ; 191: 106406, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199273

RESUMO

BACKGROUND: Parkinson's disease (PD) patients exhibit an imbalance between neuronal activity and perfusion, referred to as abnormal neurovascular coupling (NVC). Nevertheless, the underlying molecular mechanism and how levodopa, the standard treatment in PD, regulates NVC is largely unknown. MATERIAL AND METHODS: A total of 52 drug-naïve PD patients and 49 normal controls (NCs) were enrolled. NVC was characterized in vivo by relating cerebral blood flow (CBF) and amplitude of low-frequency fluctuations (ALFF). Motor assessments and MRI scanning were conducted on drug-naïve patients before and after levodopa therapy (OFF/ON state). Regional NVC differences between patients and NCs were identified, followed by an assessment of the associated receptors/transporters. The influence of levodopa on NVC, CBF, and ALFF within these abnormal regions was analyzed. RESULTS: Compared to NCs, OFF-state patients showed NVC dysfunction in significantly lower NVC in left precentral, postcentral, superior parietal cortex, and precuneus, along with higher NVC in left anterior cingulate cortex, right olfactory cortex, thalamus, caudate, and putamen (P-value <0.0006). The distribution of NVC differences correlated with the density of dopaminergic, serotonin, MU-opioid, and cholinergic receptors/transporters. Additionally, levodopa ameliorated abnormal NVC in most of these regions, where there were primarily ALFF changes with limited CBF modifications. CONCLUSION: Patients exhibited NVC dysfunction primarily in the striato-thalamo-cortical circuit and motor control regions, which could be driven by dopaminergic and nondopaminergic systems, and levodopa therapy mainly restored abnormal NVC by modulating neuronal activity.


Assuntos
Acoplamento Neurovascular , Doença de Parkinson , Humanos , Levodopa/farmacologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico , Putamen , Circulação Cerebrovascular , Dopamina
7.
Clin Anat ; 37(2): 218-226, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38186377

RESUMO

Symmetry is an essential component of esthetic assessment. Accurate assessment of facial symmetry is critical to the treatment plan of orthognathic surgery and orthodontic treatment. However, there is no internationally accepted midsagittal plane (MSP) for orthodontists and orthognathic surgeons. The purpose of this study was to explore a clinically friendly MSP, which is more accurate and reliable than what is commonly used in symmetry assessment. Forty patients with symmetric craniofacial structures were analyzed on cone-beam computed tomography (CBCT) scans. The CBCT data were exported to the Simplant Pro software to build four reference planes that were constructed by nasion (N), basion (Ba), sella (S), odontoid (Dent), or incisive foramen (IF). A total of 31 landmarks were located to determine which reference plane is the most optimal MSP by comparing the asymmetry index (AI). The mean value of AI showed a significant difference (p < 0.05) among four reference planes. Also, the mean value of AI for all landmarks showed that Plane 2 (consisting of N, Ba, and IF) and Plane 4 (consisting of N, IF, and Dent) were more accurate and stable. In conclusion, the MSP consisting of N, Dent, and IF shows more accuracy and reliability than the other planes. Further, it is more clinically friendly because of its significant advantage in landmarking.


Assuntos
Pontos de Referência Anatômicos , Tomografia Computadorizada de Feixe Cônico , Humanos , Reprodutibilidade dos Testes , Pontos de Referência Anatômicos/diagnóstico por imagem , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Ossos Faciais , Imageamento Tridimensional/métodos
9.
Eur J Neurol ; 31(2): e16108, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37877681

RESUMO

BACKGROUND AND PURPOSE: The specific pathophysiological mechanisms underlying postural instability/gait difficulty (PIGD) and cognitive function in Parkinson's disease (PD) remain unclear. Both postural and gait control, as well as cognitive function, are associated with the cholinergic basal forebrain (cBF) system. METHODS: A total of 84 PD patients and 82 normal controls were enrolled. Each participant underwent motor and cognitive assessments. Diffusion tensor imaging was used to detect structural abnormalities in the cBF system. The cBF was segmented using FreeSurfer, and its fiber tract was traced using probabilistic tractography. To provide information on extracellular water accumulation, free-water fraction (FWf) was quantified. FWf in the cBF and its fiber tract, as well as cortical projection density, were extracted for statistical analyses. RESULTS: Patients had significantly higher FWf in the cBF (p < 0.001) and fiber tract (p = 0.021) than normal controls, as well as significantly lower cBF projection in the occipital (p < 0.001), parietal (p < 0.001) and prefrontal cortex (p = 0.005). In patients, a higher FWf in the cBF correlated with worse PIGD score (r = 0.306, p = 0.006) and longer Trail Making Test A time (r = 0.303, p = 0.007). Attentional function (Trail Making Test A) partially mediated the association between FWf in the cBF and PIGD score (indirect effect, a*b = 0.071; total effect, c = 0.256; p = 0.006). CONCLUSIONS: Our findings suggest that degeneration of the cBF system in PD, from the cBF to its fiber tract and cortical projection, plays an important role in cognitive-motor interaction.


Assuntos
Prosencéfalo Basal , Transtornos Neurológicos da Marcha , Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Imagem de Tensor de Difusão , Prosencéfalo Basal/diagnóstico por imagem , Atenção , Marcha , Água , Colinérgicos , Transtornos Neurológicos da Marcha/diagnóstico por imagem , Transtornos Neurológicos da Marcha/etiologia , Equilíbrio Postural/fisiologia
10.
CNS Neurosci Ther ; 30(4): e14540, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-37994682

RESUMO

AIMS: To explore the cortical structural reorganization in Parkinson's disease (PD) patients under chronic dopamine replacement therapy (DRT) in cross-sectional and longitudinal data and determine whether these changes were associated with clinical alterations. METHODS: A total of 61 DRT-treated, 60 untreated PD patients, and 61 normal controls (NC) were retrospectively included. Structural MRI scans and neuropsychological tests were conducted. Cortical thickness and volume were extracted based on FreeSurfer and were analyzed using general linear model to find statistically significant differences among three groups. Correlation analyses were performed among significant cortical areas, medication treatment (duration and dosage), and neuropsychological tests. Longitudinal cortical structural changes of patients who initiated DRT were analyzed using linear mixed-effect model. RESULTS: Significant cortical atrophy was primarily observed in the prefrontal cortex in treated patients, including the cortical thickness of right pars opercularis and the volume of bilateral superior frontal cortex (SFC), left rostral anterior cingulate cortex (rACC), right lateral orbital frontal cortex, right pars orbitalis, and right rostral middle frontal cortex. A negative correlation was detected between the left SFC volume and levodopa equivalent dose (LED) (r = -0.316, p = 0.016), as well as the left rACC volume and medication duration (r = -0.329, p = 0.013). In the patient group, the left SFC volume was positively associated with digit span forward score (r = 0.335, p = 0.017). The left SFC volume reduction was longitudinally correlated with increased LED (standardized coefficient = -0.077, p = 0.001). CONCLUSION: This finding provided insights into the influence of DRT on cortical structure and highlighted the importance of drug dose titration in DRT.


Assuntos
Dopamina , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/complicações , Estudos Transversais , Estudos Retrospectivos , Levodopa/uso terapêutico , Imageamento por Ressonância Magnética
11.
Ann Nucl Cardiol ; 9(1): 54-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38058572

RESUMO

Background: Cross-calibration of 123I-labeled meta-iodobenzylguanidine (mIBG) myocardial-derived indices is essential to extrapolate findings from several clinical centers. Here, we conducted a phantom study to generate conversion coefficients for the calibration of heart-to-mediastinum ratios and compare them between Taiwan and Europe. Methods: We used an acrylic phantom dedicated to 123I-mIBG planar imaging to calculate the conversion coefficients of 136 phantom images derived from 36 Taiwanese institutions. A European phantom image database including 191 images from 27 institutions was used. Conversion coefficients were categorized into five collimator types: low-energy (LE) high-resolution (LEHR), LE general-purpose (LEGP), extended LEGP (ELEGP), medium-energy (ME) GP (MEGP), and ME low-penetration (MELP) collimators. Results: The conversion coefficients were 0.53 ± 0.039, 0.59 ± 0.032, 0.79 ± 0.032, 0.96 ± 0.038, and 0.99 ± 0.050 for LEHR, LEGP, ELEGP, MEGP, and MELP collimators, respectively. The Taiwanese and European conversion coefficients for the LEHR, LEGP, and MELP collimators did not significantly differ. The coefficient of variation was slightly higher for the Taiwanese than the European conversion coefficients (3.7%-7.5% vs. 2.3%-5.6%). Conclusions: We calculated conversion coefficients for various types of collimators used in Taiwan using a 123I-mIBG phantom. In general, the Taiwanese and European conversion coefficients were comparable. These findings further corroborated and highlighted the need for 123I-mIBG standardization using the phantom-determined conversion coefficients.

12.
Opt Lett ; 48(21): 5803-5806, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910763

RESUMO

We proposed and experimentally demonstrated a high-spatial-resolution distributed acoustic sensor based on time-frequency-multiplexing (TFM) optical frequency domain reflectometry (OFDR). The TFM technique enhances the frequency response of OFDR by multiplexing the time-frequency channels and suppresses the crosstalk in the meantime. Phase demodulation is employed to achieve high sensitivity, and the impact of end effect in OFDR is studied and suppressed by a dedicated linear interpolation. In the results, a 10.5 kHz vibration is measured with 22 cm spatial resolution and 20 dB signal-to-noise ratio on a 1 km fiber. By adjusting the parameters, the system also shows a good DAS performance on a 33 kHz vibration with up to 200 kHz sampling rate.

13.
Int Orthod ; 21(4): 100815, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37839391

RESUMO

OBJECTIVE: The modified clear twin-block aligner (CTBA) was developed to provide a mandibular advancement appliance for the treatment of mandibular retrognathia. The objective of this study was to analyse the stress distribution changes of CTBA with 45°, 60° and 70° bite blocks. MATERIAL AND METHODS: A three-dimensional model of the craniomaxillofacial bones and teeth was generated from a spiral computed tomography (CT) scan. The models of the articular disc, capsule, periodontal ligament and CTBA were constructed mathematically. After assigning the appropriate material properties and the boundary condition using ABAQUS software, we simulated the CTBA with different bite blocks to analyse the mechanical effects. RESULTS: In the temporomandibular joint (TMJ) region, the posterior aspect of the condyle and glenoid fossa experienced tensile stress that was approximately about 22 times greater at 70° than at 45°. The Von Mises stress distribution on the articular disc tended to be uniform. The strain direction of the condyle was backward. In the maxillary bone, the stress on the labial alveolar bone was about 5.83MPa at 70° and greater than that on the lingual side. The resulting displacement of the dentition revealed a tendency for the upper teeth to shift backward and the lower teeth to move forward by 0.46 to 0.49mm. The foregoing stress and displacement rose as the angle of the bite blocks increased. CONCLUSIONS: CTBA with 70° bite blocks constituted an advantageous biomechanical setting for the treatment of mandibular retrognathia in teenagers and provided a superior therapeutic effect.


Assuntos
Avanço Mandibular , Retrognatismo , Humanos , Adolescente , Côndilo Mandibular , Retrognatismo/terapia , Análise de Elementos Finitos , Articulação Temporomandibular/diagnóstico por imagem
14.
Int J Med Inform ; 178: 105213, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37690224

RESUMO

PURPOSE: Considering the significant workload of nursing tasks, enhancing the efficiency of nursing documentation is imperative. This study aimed to evaluate the effectiveness of a machine learning-based speech recognition (SR) system in reducing the clinical workload associated with typing nursing records, implemented in a psychiatry ward. METHODS: The study was conducted between July 15, 2020, and June 30, 2021, at Cheng Hsin General Hospital in Taiwan. The language corpus was based on the existing records from the hospital nursing information system. The participating ward's nursing activities, clinical conversation, and accent data were also collected for deep learning-based SR-engine training. A total of 21 nurses participated in the evaluation of the SR system. Documentation time and recognition error rate were evaluated in parallel between SR-generated records and keyboard entry over 4 sessions. Any differences between SR and keyboard transcriptions were regarded as SR errors. FINDINGS: A total of 200 data were obtained from four evaluation sessions, 10 participants were asked to use SR and keyboard entry in parallel at each session and 5 entries were collected from each participant. Overall, the SR system processed 30,112 words in 32,456 s (0.928 words per second). The mean accuracy of the SR system improved after each session, from 87.06% in 1st session to 95.07% in 4th session. CONCLUSION: This pilot study demonstrated our machine learning-based SR system has an acceptable recognition accuracy and may reduce the burden of documentation for nurses. However, the potential error with the SR transcription should continually be recognized and improved. Further studies are needed to improve the integration of SR in digital documentation of nursing records, in terms of both productivity and accuracy across different clinical specialties.


Assuntos
Interface para o Reconhecimento da Fala , Fala , Humanos , Projetos Piloto , Percepção , Documentação
15.
Neuroimage ; 279: 120305, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37562719

RESUMO

BACKGROUND: Large heterogeneity can be found in dopamine responsiveness of patients with Parkinson's disease (PD). Instantly and objectively understanding dopamine responsiveness of patients may help clinical practice. PURPOSE: This PD study explored the predictability of off-state inter-regional cerebral blood flow (CBF) perfusion similarity on patient's dopamine responsiveness and tested whether the predictive power could be moderated by patient's cognitive status. MATERIALS AND METHOD: The PD cohort with 192 patients (containing off state and on state (PD-off and PD-on)) and the normal control (NC) cohort with 92 subjects were included. The intra-individual CBF relative variation networks were constructed and compared between PD-off and PD-on, PD-off and NC to identify the alterations caused by dopamine depletion. Based on that, regression analysis of off-state inter-regional CBF perfusion similarity on patient's dopamine responsiveness was performed. Finally, moderation analysis was conducted to test the moderation role of cognition on the regression model. RESULTS: In the PD-off cohort, a total of 82 edges in the network were identified that affected by dopamine depletion. Off-state inter-regional CBF perfusion similarity was found that had a significant influence on patient's dopamine responsiveness. Cognitive status was validated that positively moderated the relationship between off-state inter-regional CBF perfusion similarity and dopamine responsiveness. CONCLUSION: Dopamine responsiveness of PD patient could be predicted by off-state inter-regional CBF perfusion similarity. Patient's cognitive status might have a positive moderation effect on his/her dopamine responsiveness.


Assuntos
Encéfalo , Doença de Parkinson , Humanos , Masculino , Feminino , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico , Dopamina , Imageamento por Ressonância Magnética , Cognição/fisiologia , Circulação Cerebrovascular/fisiologia , Perfusão
16.
NPJ Parkinsons Dis ; 9(1): 111, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443179

RESUMO

Increasing evidence suggests that Parkinson's disease (PD) exhibits disparate spatial and temporal patterns of progression. Here we used a machine-learning technique-Subtype and Stage Inference (SuStaIn) - to uncover PD subtypes with distinct trajectories of clinical and neurodegeneration events. We enrolled 228 PD patients and 119 healthy controls with comprehensive assessments of olfactory, autonomic, cognitive, sleep, and emotional function. The integrity of substantia nigra (SN), locus coeruleus (LC), amygdala, hippocampus, entorhinal cortex, and basal forebrain were assessed using diffusion and neuromelanin-sensitive MRI. SuStaIn model with above clinical and neuroimaging variables as input was conducted to identify PD subtypes. An independent dataset consisting of 153 PD patients and 67 healthy controls was utilized to validate our findings. We identified two distinct PD subtypes: subtype 1 with rapid eye movement sleep behavior disorder (RBD), autonomic dysfunction, and degeneration of the SN and LC as early manifestations, and cognitive impairment and limbic degeneration as advanced manifestations, while subtype 2 with hyposmia, cognitive impairment, and limbic degeneration as early manifestations, followed later by RBD and degeneration of the LC in advanced disease. Similar subtypes were shown in the validation dataset. Moreover, we found that subtype 1 had weaker levodopa response, more GBA mutations, and poorer prognosis than subtype 2. These findings provide new insights into the underlying disease biology and might be useful for personalized treatment for patients based on their subtype.

17.
CNS Neurosci Ther ; 29(12): 4160-4171, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37408389

RESUMO

AIMS: The purpose of this study was to clarify the dentato-rubro-thalamic (DRT) pathway in action tremor in comparison to normal controls (NC) and disease controls (i.e., rest tremor) by using multi-modality magnetic resonance imaging (MRI). METHODS: This study included 40 essential tremor (ET) patients, 57 Parkinson's disease (PD) patients (29 with rest tremor, 28 without rest tremor), and 41 NC. We used multi-modality MRI to comprehensively assess major nuclei and fiber tracts of the DRT pathway, which included decussating DRT tract (d-DRTT) and non-decussating DRT tract (nd-DRTT), and compared the differences in DRT pathway components between action and rest tremor. RESULTS: Bilateral dentate nucleus (DN) in the ET group had excessive iron deposition compared with the NC group. Compared with the NC group, significantly decreased mean diffusivity and radial diffusivity were observed in the left nd-DRTT in the ET group, which were negatively correlated with tremor severity. No significant difference in each component of the DRT pathway was observed between the PD subgroup or the PD and NC. CONCLUSION: Aberrant changes in the DRT pathway may be specific to action tremor and were indicating that action tremor may be related to pathological overactivation of the DRT pathway.


Assuntos
Estimulação Encefálica Profunda , Tremor Essencial , Humanos , Tremor/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Tálamo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/terapia , Estimulação Encefálica Profunda/métodos
18.
Opt Express ; 31(11): 18098-18108, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381528

RESUMO

We propose and demonstrate a high-performance distributed dynamic absolute strain sensing technique by synthesizing φ-OTDR and BOTDR. The technique synthesizes the relative strain obtained by the φ-OTDR part and the initial strain offset estimated by fitting the relative strain with the absolute strain signal from the BOTDR part. As a result, it provides not only the characteristics of high sensing accuracy and high sampling rate like φ-OTDR, but also the absolute strain measurement and the large sensing dynamic range like BOTDR. The experiment results indicate the proposed technique can realize the distributed dynamic absolute strain sensing with a sensing dynamic range of over 2500 µÉ›, a peak-to-peak amplitude of 1165 µÉ›, and a wide frequency response range from 0.1 to over 30 Hz over a sensing range of about 1 km.

19.
Neurobiol Dis ; 184: 106216, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37385459

RESUMO

Gait impairment is a common symptom of Parkinson's disease (PD), but its neural signature remains unclear due to the interindividual variability of gait performance. Identifying a robust gait-brain correlation at the individual level would provide insight into a generalizable neural basis of gait impairment. In this context, this study aimed to detect connectome that can predict individual gait function of PD, and follow-up analyses assess the molecular architecture underlying the connectome by relating it to the neurotransmitter-receptor/transporter density maps. Resting-state functional magnetic resonance imaging was used to detect the functional connectome, and gait function was assessed via a 10 m-walking test. The functional connectome was first detected within drug-naive patients (N = 48) by using connectome-based predictive modeling following cross-validation and then successfully validated within drug-managed patients (N = 30). The results showed that the motor, subcortical, and visual networks played an important role in predicting gait function. The connectome generated from patients failed to predict the gait function of 33 normal controls (NCs) and had distinct connection patterns compared to NCs. The negative connections (connection negatively correlated with 10 m-walking-time) pattern of the PD connectome was associated with the density of the D2 receptor and VAChT transporter. These findings suggested that gait-associated functional alteration induced by PD pathology differed from that induced by aging degeneration. The brain dysfunction related to gait impairment was more commonly found in regions expressing more dopaminergic and cholinergic neurotransmitters, which may aid in developing targeted treatments.


Assuntos
Conectoma , Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Conectoma/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/patologia , Marcha
20.
CNS Neurosci Ther ; 29(11): 3507-3517, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37305965

RESUMO

AIMS: To detect functional connectomes of akinetic-rigid (AR) and tremor and compare their connection pattern. METHODS: Resting-state functional MRI data of 78 drug-naïve PD patients were enrolled to construct connectomes of AR and tremor via connectome-based predictive modeling (CPM). The connectomes were further validated with 17 drug-naïve patients to verify their replication. RESULTS: The connectomes related to AR and tremor were identified via CPM method and successfully validated in the independent set. Additional regional-based CPM demonstrated neither AR nor tremor could be simplified to functional changes within a single brain region. Computational lesion version of CPM revealed that parietal lobe and limbic system were the most important regions among AR-related connectome, and motor strip and cerebellum were the most important regions among tremor-related connectome. Comparing two connectomes found that the patterns of connection between them were largely distinct, with only four overlapped connections identified. CONCLUSION: AR and tremor were found to be associated with functional changes in multiple brain regions. Distinct connection patterns of AR-related and tremor-related connectomes suggest different neural mechanisms underlying the two symptoms.


Assuntos
Conectoma , Doença de Parkinson , Humanos , Tremor/diagnóstico por imagem , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Encéfalo/patologia , Cerebelo/diagnóstico por imagem , Imageamento por Ressonância Magnética
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