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  • Wiley  (381)
  • 1
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    Substantia nigra iron affects functional connectivity networks modifying working memory performance in younger adults
    Wiley ; 2021
    In:  European Journal of Neuroscience Vol. 54, No. 11 ( 2021-12), p. 7959-7973
    Details
    In: European Journal of Neuroscience, Wiley, Vol. 54, No. 11 ( 2021-12), p. 7959-7973
    Abstract: Brain iron affects working memory (WM) but the impact of iron content in deep grey matter nuclei on WM networks is unknown. We aimed to test whether deep grey matter nuclei iron concentration can affect resting‐state functional connectivity (rsFC) within brain networks modifying WM performance. An N‐back WM paradigm was applied in a hundred healthy younger adults. The participants then underwent a resting‐state functional magnetic resonance imaging (fMRI) for brain network analysis and quantitative susceptibility mapping (QSM) imaging for assessment of deep grey matter nuclei iron concentration. Higher substantia nigra (SN) iron concentration was associated with lower rsFC between SN and brain regions of the temporal/frontal lobe but with better WM performance after controlling for age, gender and education. A follow‐up mediation analysis also indicated that functional connectivity may mediate the link between SN iron and WM performance. Our results suggest that high SN iron concentration may affect communication between the SN and temporal/frontal lobe and is associated with strengthened WM performance in younger adults.
    Type of Medium: Online Resource
    ISSN: 0953-816X , 1460-9568
    URL: Issue
    URL: Article
    DOI: 10.1111/ejn.v54.11
    DOI: 10.1111/ejn.15532
    Language: English
    Publisher: Wiley
    Publication Date: 2021
    detail.hit.zdb_id: 2005178-5
    SSG: 12
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  • 2
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    Aberrant Fiber Coherence of Amygdala−Accumbens−Pallidum Pathway Is Associated With Disorganized Nigrostriatal−Nigropallidal Pathway in Parkinson's Disease
    Wiley ; 2020
    In:  Journal of Magnetic Resonance Imaging Vol. 52, No. 6 ( 2020-12), p. 1799-1808
    Details
    In: Journal of Magnetic Resonance Imaging, Wiley, Vol. 52, No. 6 ( 2020-12), p. 1799-1808
    Abstract: Motor disturbances in Parkinson's disease (PD) mainly result from the degeneration of classic motor pathways. Given that the specific limbic pathway participates in movements, it is reasonable to consider that limbic pathway have the pathologic potential of motor disturbance in PD. Purpose To explore the white matter changes of limbic and motor pathways and their relations in PD patients. Study Type Prospective. Population 39 PD patients and 55 normal controls. Sequence Sagittal 3D T 1 ‐weighted fast spoiled gradient recalled sequence, diffusion‐weighted spin echo‐echo planar imaging sequence on a 3T scanner. Assessment Probabilistic tractography was used to reconstruct the motor pathways (nigrostriatal−nigropallidal and basal ganglia−motor cortex pathways) and limbic pathway (amygdala−accumbens−pallidum pathway). White matter alterations of these pathways were evaluated by fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), neurite density (NDI), and orientation dispersion (ODI). Clinical assessment was conducted by a neurologist. Statistical Tests Group comparisons were performed using unpaired t ‐tests. Pearson or Spearman correlation was used to explore the relationships between variables. Results Compared with normal controls, PD patients showed decreased ODI as well as increased MD and AD in the bilateral nigrostriatal−nigropallidal pathway ( P   〈  0.05), decreased FA in left basal ganglia−motor cortex pathway ( P   〈  0.05), and decreased ODI in left limbic pathway ( P   〈  0.05). MD and AD in the left nigrostriatal−nigropallidal pathway was negatively correlated with FA in left basal ganglia−motor cortex pathway ( r =  −0.597, P   〈  0.05 and r =  −0.433, P   〈  0.05, respectively). MD in the left nigrostriatal−nigropallidal pathway was significantly correlated with ODI in the left limbic pathway ( r =  −0.404, P   〈  0.05). ODI was associated with AD within each hemisphere of the nigrostriatal−nigropallidal pathway ( r =  −0.591, P   〈  0.05 for left; r =  −0.589, P   〈  0.05 for right). Data Conclusion The relationship between the degenerated motor pathways and aberrant limbic pathway suggest the existence of neuronal modulation between motor and limbic pathways, providing novel evidence of the neuromechanism for motor disruption in PD patients. Level of Evidence 2 Technical Efficacy Stage 1 J. MAGN. RESON. IMAGING 2020;52:1799–1808.
    Type of Medium: Online Resource
    ISSN: 1053-1807 , 1522-2586
    URL: Issue
    URL: Article
    DOI: 10.1002/jmri.v52.6
    DOI: 10.1002/jmri.27273
    Language: English
    Publisher: Wiley
    Publication Date: 2020
    detail.hit.zdb_id: 1497154-9
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  • 3
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    Increased thalamic centrality and putamen–thalamic connectivity in patients with parkinsonian resting tremor
    Wiley ; 2017
    In:  Brain and Behavior Vol. 7, No. 1 ( 2017-01)
    Details
    In: Brain and Behavior, Wiley, Vol. 7, No. 1 ( 2017-01)
    Abstract: Evidence has indicated a strong association between hyperactivity in the cerebello‐thalamo‐motor cortical loop and resting tremor in Parkinson's disease ( PD ). Within this loop, the thalamus serves as a central hub based on its structural centrality in the generation of resting tremor. To study whether this thalamic abnormality leads to an alteration at the whole‐brain level, our study investigated the role of the thalamus in patients with parkinsonian resting tremor in a large‐scale brain network context. Methods Forty‐one patients with PD (22 with resting tremor, TP and 19 without resting tremor, NTP ) and 45 healthy controls ( HC ) were included in this resting‐state functional MRI study. Graph theory‐based network analysis was performed to examine the centrality measures of bilateral thalami across the three groups. To further provide evidence to the central role of the thalamus in parkinsonian resting tremor, the seed‐based functional connectivity analysis was then used to quantify the functional interactions between the basal ganglia and the thalamus. Results Compared with the HC group, patients with the TP group exhibited increased degree centrality ( p  〈  .04), betweenness centrality ( p  〈  .01), and participation coefficient ( p  〈  .01) in the bilateral thalami. Two of these alterations (degree centrality and participation coefficient) were significantly correlated with tremor severity, especially in the left hemisphere ( p  〈  .02). The modular analysis showed that the TP group had more intermodular connections between the thalamus and the regions within the cerebello‐thalamo‐motor cortical loop. Furthermore, the data revealed significantly enhanced functional connectivity between the putamen and the thalamus in the TP group ( p  = .027 corrected for family‐wise error). Conclusions These findings suggest increased thalamic centrality as a potential tremor‐specific imaging measure for PD , and provide evidence for the altered putamen–thalamic interaction in patients with resting tremor.
    Type of Medium: Online Resource
    ISSN: 2162-3279 , 2162-3279
    URL: Issue
    URL: Article
    DOI: 10.1002/brb3.2017.7.issue-1
    DOI: 10.1002/brb3.601
    Language: English
    Publisher: Wiley
    Publication Date: 2017
    detail.hit.zdb_id: 2623587-0
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  • 4
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    Effects of APOE ε2 allele on basal forebrain functional connectivity in mild cognitive impairment
    Wiley ; 2023
    In:  CNS Neuroscience & Therapeutics Vol. 29, No. 2 ( 2023-02), p. 597-608
    Details
    In: CNS Neuroscience & Therapeutics, Wiley, Vol. 29, No. 2 ( 2023-02), p. 597-608
    Abstract: Basal forebrain cholinergic system (BFCS) dysfunction is associated with cognitive decline in Alzheimer's disease (AD) and mild cognitive impairment (MCI). Apolipoprotein E ( APOE ) ε2 is a protective genetic factor in AD and MCI, and cholinergic sprouting depends on APOE . Objective We investigated the effect of the APOE ε2 allele on BFCS functional connectivity (FC) in cognitively normal (CN) subjects and MCI patients. Method We included 60 MCI patients with APOE ε3/ε3, 18 MCI patients with APOE ε2/ε3, 73 CN subjects with APOE ε3/ε3, and 36 CN subjects with APOE ε2/ε3 genotypes who had resting‐state functional magnetic resonance imaging data from the Alzheimer's disease Neuroimaging Initiative. We used BFCS subregions (Ch1‐3 and Ch4) as seeds and calculated the FC with other brain areas. Using a mixed‐effect analysis, we explored the interaction effects of APOE ε2 allele × cognitive status on BFCS‐FC. Furthermore, we examined the relationships between imaging metrics, cognitive abilities, and AD pathology markers, controlling for sex, age, and education as covariates. Results An interaction effect on functional connectivity was found between the right Ch4 (RCh4) and left insula ( p   〈  0.05, corrected), and between the RCh4 and left Rolandic operculum ( p   〈  0.05, corrected). Among all subjects and APOE ε2 carriers, RCh4‐left Insula FC was associated with early tau deposition. Furthermore, no correlation was found between imaging metrics and amyloid burden. Among all subjects and APOE ε2 carriers, FC metrics were associated with cognitive performance. Conclusion The APOE ε2 genotype may play a protective role during BFCS degeneration in MCI.
    Type of Medium: Online Resource
    ISSN: 1755-5930 , 1755-5949
    URL: Article
    DOI: 10.1111/cns.14038
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 2423467-9
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  • 5
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    Influence of regional iron on the motor impairments of Parkinson's disease: A quantitative susceptibility mapping study
    Wiley ; 2017
    In:  Journal of Magnetic Resonance Imaging Vol. 45, No. 5 ( 2017-05), p. 1335-1342
    Details
    In: Journal of Magnetic Resonance Imaging, Wiley, Vol. 45, No. 5 ( 2017-05), p. 1335-1342
    Abstract: Because the roles of striatal‐thalamo‐cortical and cerebello‐thalamo‐cortical circuits in the heterogeneous motor impairments of Parkinson's disease (PD) are becoming recognized, this study was designed to investigate the relationships between regional iron in the cardinal subcortical nuclei in these circuits and the different motor impairments. Materials and Methods Sixty‐two PD patients and 40 normal subjects were included and accepted for Enhanced T 2 ‐Star Weighted Angiography Scanning (3.0T). According to the Unified Parkinson's Disease Rating Scale, patients were divided into tremor‐dominant (PD‐TD) and akinetic/rigid‐dominant groups (PD‐AR). The intergroup differences of magnetic susceptibility in those cardinal nuclei were measured. Correlation analyses between magnetic susceptibility and motor impairments were performed in all patients. Results Nigral magnetic susceptibility significantly increased for each PD group compared with controls ( P 〈 0.001 for PD‐TD; P  = 0.001 for PD‐AR). Magnetic susceptibility in the dentate nucleus (DN) and red nucleus (RN) for the PD‐TD patients were significantly increased compared with controls ( P 〈 0.001 and P  = 0.004, respectively). Magnetic susceptibility in these regions was also significantly correlated with tremor severity ( r  = 0.444, P  = 0.001 for DN; r  = 0.418, P  = 0.001 for RN). Significant correlation between caudate magnetic susceptibility and akinetic/rigid severity were observed ( r  = –0.322, P  = 0.015). Conclusion This study provides evidence that nigral iron accumulation is a common characteristic in PD, while iron accumulation in the DN and RN is correlated with tremor symptoms. Our data also indicate that caudate iron content may be a potential marker for akinetic/rigid progression. Level of Evidence : 3 J. MAGN. RESON. IMAGING 2017;45:1335–1342
    Type of Medium: Online Resource
    ISSN: 1053-1807 , 1522-2586
    URL: Issue
    URL: Article
    DOI: 10.1002/jmri.v45.5
    DOI: 10.1002/jmri.25434
    Language: English
    Publisher: Wiley
    Publication Date: 2017
    detail.hit.zdb_id: 1497154-9
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  • 6
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    Wheat‐Flour‐Derived Magnetic Porous Carbons by CaCl 2 ‐Activation and their Application in Cr(VI) Removal
    Wiley ; 2021
    In:  ChemistrySelect Vol. 6, No. 46 ( 2021-12-13), p. 13215-13223
    Details
    In: ChemistrySelect, Wiley, Vol. 6, No. 46 ( 2021-12-13), p. 13215-13223
    Abstract: Magnetic porous carbons were obtained from wheat flour via simple one‐step pyrolysis employing calcium chloride as activator. A series of wheat flour derived‐magnetic porous carbons (WMCs) with various pyrolysis temperature and precursor were prepared, characterized and applied for Cr(VI) removal. The results show that γ‐FeOOH and Fe 3 O 4 were respectively obtained in the WMCs at pyrolysis temperature above and below 600 °C. While, the calcium chloride enhanced the mesoporous of WMCs and promoted the crystallization of Fe 3 O 4 . The optimal sample exhibited super Cr(VI) removal capacities of 15.53 mg g −1 and good reusability after 5 recycles in neutral solution. The Cr(VI) removal of WMCs obeys pseudo‐second‐order adsorption model and Langmuir adsorption isotherms. The enhanced adsorptivity can be attributed to the incorporation of adsorption and reduction reaction between Cr(VI) ions and Fe 3 O 4 . The density functional theory calculations also demonstrated that Cr(VI) ions is more favorable and strongly adsorbed onto Fe 3 O 4 surface than γ‐FeOOH.
    Type of Medium: Online Resource
    ISSN: 2365-6549 , 2365-6549
    URL: Issue
    URL: Article
    DOI: 10.1002/slct.v6.46
    DOI: 10.1002/slct.202103079
    Language: English
    Publisher: Wiley
    Publication Date: 2021
    detail.hit.zdb_id: 2844262-3
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  • 7
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    Normalization effect of dopamine replacement therapy on brain functional connectome in Parkinson's disease
    Wiley ; 2023
    In:  Human Brain Mapping Vol. 44, No. 9 ( 2023-06-15), p. 3845-3858
    Details
    In: Human Brain Mapping, Wiley, Vol. 44, No. 9 ( 2023-06-15), p. 3845-3858
    Abstract: Dopamine replacement therapy (DRT) represents the standard treatment for Parkinson's disease (PD), however, instant and long‐term medication influence on patients' brain function have not been delineated. Here, a total of 97 drug‐naïve patients, 43 patients under long‐term DRT, and 94 normal control (NC) were, retrospectively, enrolled. Resting‐state functional magnetic resonance imaging data and motor symptom assessments were conducted before and after levodopa challenge test. Whole‐brain functional connectivity (FC) matrices were constructed. Network‐based statistics were performed to assess FC difference between drug‐naïve patients and NC, and these significant FCs were defined as disease‐related connectomes, which were used for further statistical analyses. Patients showed better motor performances after both long‐term DRT and levodopa challenge test. Two disease‐related connectomes were observed with distinct patterns. The FC of the increased connectome, which mainly consisted of the motor, visual, subcortical, and cerebellum networks, was higher in drug‐naïve patients than that in NC and was normalized after long‐term DRT ( p ‐value 〈 .050). The decreased connectome was mainly composed of the motor, medial frontal, and salience networks and showed significantly lower FC in all patients than NC ( p ‐value 〈 .050). The global FC of both increased and decreased connectome was significantly enhanced after levodopa challenge test ( q ‐value 〈 0.050, false discovery rate‐corrected). The global FC of increased connectome in ON‐state was negatively associated with levodopa equivalency dose ( r  = −.496, q ‐value = 0.007). Higher global FC of the decreased connectome was related to better motor performances ( r  = −.310, q ‐value = 0.022). Our findings provided insights into brain functional alterations under dopaminergic medication and its benefit on motor symptoms.
    Type of Medium: Online Resource
    ISSN: 1065-9471 , 1097-0193
    URL: Issue
    URL: Article
    DOI: 10.1002/hbm.v44.9
    DOI: 10.1002/hbm.26316
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 1492703-2
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  • 8
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    Direct localization and delineation of human pedunculopontine nucleus based on a self‐supervised magnetic resonance image super‐resolution method
    Wiley ; 2023
    In:  Human Brain Mapping Vol. 44, No. 9 ( 2023-06-15), p. 3781-3794
    Details
    In: Human Brain Mapping, Wiley, Vol. 44, No. 9 ( 2023-06-15), p. 3781-3794
    Abstract: The pedunculopontine nucleus (PPN) is a small brainstem structure and has attracted attention as a potentially effective deep brain stimulation (DBS) target for the treatment of Parkinson's disease (PD). However, the in vivo location of PPN remains poorly described and barely visible on conventional structural magnetic resonance (MR) images due to a lack of high spatial resolution and tissue contrast. This study aims to delineate the PPN on a high‐resolution (HR) atlas and investigate the visibility of the PPN in individual quantitative susceptibility mapping (QSM) images. We combine a recently constructed Montreal Neurological Institute (MNI) space unbiased QSM atlas (MuSus‐100), with an implicit representation‐based self‐supervised image super‐resolution (SR) technique to achieve an atlas with improved spatial resolution. Then guided by a myelin staining histology human brain atlas, we localize and delineate PPN on the atlas with improved resolution. Furthermore, we examine the feasibility of directly identifying the approximate PPN location on the 3.0‐T individual QSM MR images. The proposed SR network produces atlas images with four times the higher spatial resolution (from 1 to 0.25 mm isotropic) without a training dataset. The SR process also reduces artifacts and keeps superb image contrast for further delineating small deep brain nuclei, such as PPN. Using the myelin staining histological atlas as guidance, we first identify and annotate the location of PPN on the T1‐weighted (T1w)‐QSM hybrid MR atlas with improved resolution in the MNI space. Then, we relocate and validate that the optimal targeting site for PPN‐DBS is at the middle‐to‐caudal part of PPN on our atlas. Furthermore, we confirm that the PPN region can be identified in a set of individual QSM images of 10 patients with PD and 10 healthy young adults. The contrast ratios of the PPN to its adjacent structure, namely the medial lemniscus, on images of different modalities indicate that QSM substantially improves the visibility of the PPN both in the atlas and individual images. Our findings indicate that the proposed SR network is an efficient tool for small‐size brain nucleus identification. HR QSM is promising for improving the visibility of the PPN. The PPN can be directly identified on the individual QSM images acquired at the 3.0‐T MR scanners, facilitating a direct targeting of PPN for DBS surgery.
    Type of Medium: Online Resource
    ISSN: 1065-9471 , 1097-0193
    URL: Issue
    URL: Article
    DOI: 10.1002/hbm.v44.9
    DOI: 10.1002/hbm.26311
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 1492703-2
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  • 9
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    Generation of 13.9‐mJ Terahertz Radiation from Lithium Niobate Materials
    Wiley ; 2023
    In:  Advanced Materials Vol. 35, No. 23 ( 2023-06)
    Details
    In: Advanced Materials, Wiley, Vol. 35, No. 23 ( 2023-06)
    Abstract: Extremely strong‐field terahertz (THz) radiation in free space has compelling applications in nonequilibrium condensed matter state regulation, all‐optical THz electron acceleration and manipulation, THz biological effects, etc. However, these practical applications are constrained by the absence of high‐intensity, high‐efficiency, high‐beam‐quality, and stable solid‐state THz light sources. Here, the generation of single‐cycle 13.9‐mJ extreme THz pulses from cryogenically cooled lithium niobate crystals and a 1.2% energy conversion efficiency from 800 nm to THz are demonstrated experimentally using the tilted pulse‐front technique driven by a home‐built 30‐fs, 1.2‐Joule Ti:sapphire laser amplifier. The focused peak electric field strength is estimated to be 7.5 MV cm −1 . A record of 1.1‐mJ THz single‐pulse energy at a 450 mJ pump at room temperature is produced and observed that the self‐phase modulation of the optical pump can induce THz saturation behavior from the crystals in the substantially nonlinear pump regime. This study lays the foundation for the generation of sub‐Joule THz radiation from lithium niobate crystals and will inspire more innovations in extreme THz science and applications.
    Type of Medium: Online Resource
    ISSN: 0935-9648 , 1521-4095
    URL: Issue
    URL: Article
    DOI: 10.1002/adma.v35.23
    DOI: 10.1002/adma.202208947
    RVK:
    UA 1538
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 1474949-X
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  • 10
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    Sub‐voxel quantitative susceptibility mapping for assessing whole‐brain magnetic susceptibility from ages 4 to 80
    Wiley ; 2023
    In:  Human Brain Mapping
    Details
    In: Human Brain Mapping, Wiley
    Abstract: The evolution of magnetic susceptibility of the brain is mainly determined by myelin in white matter (WM) and iron deposition in deep gray matter (DGM). However, existing imaging techniques have limited abilities to simultaneously quantify the myelination and iron deposition within a voxel throughout brain development and aging. For instance, the temporal trajectories of iron in the brain WM and myelination in DGM have not been investigated during the aging process. This study aimed to map the age‐related iron and myelin changes in the whole brain, encompassing myelin in DGM and iron deposition in WM, using a novel sub‐voxel quantitative susceptibility mapping (QSM) method. To achieve this, a cohort of 494 healthy adults (18–80 years old) was studied. The sub‐voxel QSM method was employed to obtain the paramagnetic and diamagnetic susceptibility based on the approximated map from acquired map. The linear relationship between and maps was established from the regression coefficients on a small cohort data acquired with both 3D gradient recalled echo data and mapping. Large cohort sub‐voxel susceptibility maps were used to create longitudinal and age‐specific atlases via group‐wise registration. To explore the differential developmental trajectories in the DGM and WM, we employed nonlinear models including exponential and Poisson functions, along with generalized additive models. The constructed atlases reveal the iron accumulation in the posterior part of the putamen and the gradual myelination process in the globus pallidus with aging. Interestingly, the developmental trajectories show that the rate of myelination differs among various DGM regions. Furthermore, the process of myelin synthesis is paralleled by an associated pattern of iron accumulation in the primary WM fiber bundles. In summary, our study offers significant insights into the distinctive developmental trajectories of iron in the brain's WM and myelination/demyelination in the DGM in vivo. These findings highlight the potential of using sub‐voxel QSM to uncover new perspectives in neuroscience and improve our understanding of whole‐brain myelination and iron deposit processes across the lifespan.
    Type of Medium: Online Resource
    ISSN: 1065-9471 , 1097-0193
    URL: Article
    DOI: 10.1002/hbm.26487
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 1492703-2
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