Cortical remodeling across the lifespan in healthy brain reveals structural network vulnerability to neurodegeneration

With the development of urbanization, urban traffic has exposed many problems. To study the subway’s influence on urban traffic, this paper collects data on traffic indicators in Nanchang from 2008 to 2018. The research is carried out from three aspects: traffic accessibility, green traffic, and traffic security. First, Grey Relational Analysis is used to select 18 traffic indicators correlated with the subway from 22 traffic indicators. Second, the data is discretized and learned based on Bayesian Networks to construct the structural network of the subway’s influence. Third, to verify the reliability of using GRA and the effectiveness of Bayesian Networks (GRA-BNs), Bayesian Networks with full indicators analysis and other four algorithms (Naive Bayes, Random Decision Forest, Logistic and regression) are employed for comparison. Moreover, the receiver operating characteristic (ROC) area, true positive (TP) rate, false positive (FP) rate, precision, recall, F-measure, and accuracy are utilized for comparing each situation. The result shows that GRA-BNs is the most effective model to study the impact of the subway’s operation on urban traffic. Then, the dependence relations between the subway and each index are analyzed by the conditional probability tables (CPTs). Finally, according to the analysis, some suggestions are put forward.

Download Full-text

Aberrant Structural Network Architecture in Leber’s Hereditary Optic Neuropathy. Minimum Spanning Tree Graph Analysis Application into Diffusion 7T MRI

Neuroscience ◽

10.1016/j.neuroscience.2020.12.019 ◽

2020 ◽

Author(s):

Kamil Jonak ◽

Paweł Krukow ◽

Hanna Karakuła-Juchnowicz ◽

Mansur Rahnama-Hezavah ◽

Katarzyna E. Jonak ◽

...

Keyword(s):

Optic Neuropathy ◽

Network Architecture ◽

Spanning Tree ◽

Minimum Spanning Tree ◽

Graph Analysis ◽

Tree Graph ◽

Leber's Hereditary Optic Neuropathy ◽

Structural Network ◽

Analysis Application ◽

Hereditary Optic Neuropathy

Download Full-text

Brain pathology recapitulates physiology: A network meta-analysis

Communications Biology ◽

10.1038/s42003-021-01832-9 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Thomas J. Vanasse ◽

Peter T. Fox ◽

P. Mickle Fox ◽

Franco Cauda ◽

Tommaso Costa ◽

...

Keyword(s):

Network Architecture ◽

Spatial Scales ◽

Meta Analysis ◽

Metabolic Cost ◽

Common Mechanism ◽

Brain Disorders ◽

Brain Pathology ◽

Structural Network ◽

Meta Analyses ◽

Function Network

AbstractNetwork architecture is a brain-organizational motif present across spatial scales from cell assemblies to distributed systems. Structural pathology in some neurodegenerative disorders selectively afflicts a subset of functional networks, motivating the network degeneration hypothesis (NDH). Recent evidence suggests that structural pathology recapitulating physiology may be a general property of neuropsychiatric disorders. To test this possibility, we compared functional and structural network meta-analyses drawing upon the BrainMap database. The functional meta-analysis included results from >7,000 experiments of subjects performing >100 task paradigms; the structural meta-analysis included >2,000 experiments of patients with >40 brain disorders. Structure-function network concordance was high: 68% of networks matched (pFWE < 0.01), confirming the broader scope of NDH. This correspondence persisted across higher model orders. A positive linear association between disease and behavioral entropy (p = 0.0006;R2 = 0.53) suggests nodal stress as a common mechanism. Corroborating this interpretation with independent data, we show that metabolic ‘cost’ significantly differs along this transdiagnostic/multimodal gradient.

Download Full-text

Retrospective analysis of hemispheric structural network change as a function of location and size of glioma

Brain Communications ◽

10.1093/braincomms/fcaa216 ◽

2020 ◽

Author(s):

Shawn D’Souza ◽

Lisa Hirt ◽

David R Ormond ◽

John A Thompson

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Temporal Lobe ◽

Diffusion Tensor ◽

Brain Regions ◽

Structural Network ◽

Tumour Location ◽

The Impact ◽

Tractography Data ◽

Diffusion Tensor Imaging Tractography

Abstract Gliomas are neoplasms that arise from glial cell origin and represent the largest fraction of primary malignant brain tumours (77%). These highly infiltrative malignant cell clusters modify brain structure and function through expansion, invasion and intratumoral modification. Depending on the growth rate of the tumour, location and degree of expansion, functional reorganization may not lead to overt changes in behaviour despite significant cerebral adaptation. Studies in simulated lesion models and in patients with stroke reveal both local and distal functional disturbances, using measures of anatomical brain networks. Investigations over the last two decades have sought to use diffusion tensor imaging tractography data in the context of intracranial tumours to improve surgical planning, intraoperative functional localization, and post-operative interpretation of functional change. In this study, we used diffusion tensor imaging tractography to assess the impact of tumour location on the white matter structural network. To better understand how various lobe localized gliomas impact the topology underlying efficiency of information transfer between brain regions, we identified the major alterations in brain network connectivity patterns between the ipsilesional versus contralesional hemispheres in patients with gliomas localized to the frontal, parietal or temporal lobe. Results were indicative of altered network efficiency and the role of specific brain regions unique to different lobe localized gliomas. This work draws attention to connections and brain regions which have shared structural susceptibility in frontal, parietal and temporal lobe glioma cases. This study also provides a preliminary anatomical basis for understanding which affected white matter pathways may contribute to preoperative patient symptomology.

Download Full-text

Analysis of Sequence Divergence in Mammalian ABCGs Predicts a Structural Network of Residues That Underlies Functional Divergence

International Journal of Molecular Sciences ◽

10.3390/ijms22063012 ◽

2021 ◽

Vol 22 (6) ◽

pp. 3012

Author(s):

James I. Mitchell-White ◽

Thomas Stockner ◽

Nicholas Holliday ◽

Stephen J. Briddon ◽

Ian D. Kerr

Keyword(s):

Substrate Specificity ◽

Functional Divergence ◽

3D Structure ◽

Sequence Divergence ◽

Conformational Flexibility ◽

Substrate Selectivity ◽

Multiple Sequence ◽

Atp Binding Cassette Transporters ◽

Structural Network ◽

Wide Substrate Specificity

The five members of the mammalian G subfamily of ATP-binding cassette transporters differ greatly in their substrate specificity. Four members of the subfamily are important in lipid transport and the wide substrate specificity of one of the members, ABCG2, is of significance due to its role in multidrug resistance. To explore the origin of substrate selectivity in members 1, 2, 4, 5 and 8 of this subfamily, we have analysed the differences in conservation between members in a multiple sequence alignment of ABCG sequences from mammals. Mapping sets of residues with similar patterns of conservation onto the resolved 3D structure of ABCG2 reveals possible explanations for differences in function, via a connected network of residues from the cytoplasmic to transmembrane domains. In ABCG2, this network of residues may confer extra conformational flexibility, enabling it to transport a wider array of substrates.

Download Full-text

Categories of context in realist evaluation

Evaluation ◽

10.1177/1356389020968578 ◽

2021 ◽

Vol 27 (2) ◽

pp. 184-209

Author(s):

Rod Sheaff ◽

Natasha Doran ◽

Michael Harris ◽

Iain Lang ◽

Antionieta Medina-Lara ◽

...

Keyword(s):

Patient Safety ◽

Policy Implementation ◽

Realist Evaluation ◽

Temporal Continuity ◽

Network Hierarchy ◽

Structural Network

Realist evaluation has become widespread partly because of its sensitivity to the influence of contexts on policy implementation. In many such evaluations, the range of contexts considered relevant nevertheless remains disparate and under-conceptualised. This article uses findings from a realist evaluation of English Patient Safety Collaboratives during 2015–2018 to develop a realist taxonomy of contexts, differentiating contexts according to how they affect the corresponding policy mechanism. By analysing the main context-mechanism-outcome configurations that made up the English Patient Safety Collaboratives, we derive a taxonomy of the contexts that affected implementation and outcomes. The categories of context were structural (network, hierarchy, market and organisational contexts); resource-based (actors, material, financial); motivational (receptivity, outcome headroom), and temporal (continuity, history and convergence). To the categories found in previous studies, this study adds the three temporal contexts.

Download Full-text