The patterns of the large-scale spatial organization of chromatin in interphase human somatic cells are not random. Such patterns include the radial separation of euchromatin and heterochromatin, the territorial organization of individual chromosomes, the non-random locations of chromosome territories and the differential positioning of the two X chromosomes in female cells. These features of large-scale nuclear architecture follow naturally from the hypothesis that ATP-consuming non-equilibrium processes associated with highly transcribed regions of chromosomes are a source of 'active' forces. These forces are in excess of those that arise from Brownian motion. Simulations of model chromosomes that incorporate such activity recapitulate these features. In addition, they reproduce many other aspects of the spatial organization of chromatin at large scales that are known from experiments. Our results, reviewed here, suggest that the distribution of transcriptional activity across chromosomes underlies many aspects of large-scale nuclear architecture that were hitherto believed to be unrelated.
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http://dx.doi.org/10.1042/ETLS20200010 | DOI Listing |
BMC Public Health
January 2025
School of Medicine, Hangzhou City University, Hangzhou, 310015, China.
Background: In the context of public health emergencies, the presence of medical and health talents (MHT) is critically important for support in any country or region. This study aims to analyze the spatial and temporal distributions and evolution of MHT in China and propose strategies and recommendations for promoting a balanced distribution.
Methods: This research used data from 31 provinces in China to construct a multidimensional index system for measuring the agglomeration level of MHT.
Plant Cell
January 2025
Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria.
Super-resolution methods provide far better spatial resolution than the optical diffraction limit of about half the wavelength of light (∼200-300 nm). Nevertheless, they have yet to attain widespread use in plants, largely due to plants' challenging optical properties. Expansion microscopy improves effective resolution by isotropically increasing the physical distances between sample structures while preserving relative spatial arrangements and clearing the sample.
View Article and Find Full Text PDFJ Alzheimers Dis
January 2025
Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Background: White matter hyperintensities (WMH) are prominent neuroimaging markers of cerebral small vessel disease (CSVD) linked to cognitive decline. Nevertheless, the pathophysiological mechanisms underlying WMH remain unclear.
Objective: This study aimed to assess the structural decoupling index (SDI) as a novel metric for quantifying the brain's hierarchical organization associated with WMH in cognitively normal older adults
Methods: We analyzed data from 112 cognitively normal individuals with varying WMH burdens (43 high WMH burden and 69 low WMH burden).
J Headache Pain
January 2025
Department of Brain and Cognitive Engineering, Korea University, Seoul, Republic of Korea.
Inter-individual variability in symptoms and the dynamic nature of brain pathophysiology present significant challenges in constructing a robust diagnostic model for migraine. In this study, we aimed to integrate different types of magnetic resonance imaging (MRI), providing structural and functional information, and develop a robust machine learning model that classifies migraine patients from healthy controls by testing multiple combinations of hyperparameters to ensure stability across different migraine phases and longitudinally repeated data. Specifically, we constructed a diagnostic model to classify patients with episodic migraine from healthy controls, and validated its performance across ictal and interictal phases, as well as in a longitudinal setting.
View Article and Find Full Text PDFSci Rep
January 2025
Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Yamadaoka 2-1, Suita, 565-0871, Osaka, Japan.
Heterogeneity is a critical determinant for multicellular pattern formation. Although the importance of microscale and macroscale heterogeneity at the single-cell and whole-system levels, respectively, has been well accepted, the presence and functions of mesoscale heterogeneity, such as cell clusters with distinct properties, have been poorly recognized. We investigated the biological importance of mesoscale heterogeneity in signal-relaying abilities (excitability) in the self-organization of spiral waves of intercellular communications by studying the self-organized pattern formation in a population of Dictyostelium discoideum cells, a classical signal-relaying system model.
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