BackgroundPrimary insomnia can severely impair daytime function by disrupting attention and working memory and imposes a danger to self and others by increasing the risk of accidents. We speculated that the neurobiological changes impeding working memory in primary insomnia patients would be revealed by resting-state functional MRI (R-fMRI), which estimates the strength of cortical pathways by measuring local and regional correlations in blood oxygen level dependent (BOLD) signs independent of specific task demands.MethodsWe compared the R-fMRI activity patterns of 15 healthy controls to 15 primary insomnia patients (all 30 participants were right-handed) using a 3.0 T MRI scanner. The SPM8 and REST1.7 software packages were used for preprocessing and analysis. Activity was expressed relative to the superior parietal lobe (SPL, the seed region) to reveal differences in functional connectivity to other cortical regions implicated in spatial working memory.ResultIn healthy controls, bilateral SPL activity was associated with activity in the posterior cingulate gyrus, precuneus, ventromedial prefrontal cortex, and superior frontal gyrus, indicating functional connectivity between these regions. Strong functional connectivity between the SPL and bilateral pre-motor cortex, bilateral supplementary motor cortex, and left dorsolateral prefrontal cortex was observed in both the control group and the primary insomnia group. However, the strength of several other functional connectivity pathways to the SPL exhibited significant group differences. Compared to healthy controls, connectivity in the primary insomnia group was stronger between the bilateral SPL and the right ventral anterior cingulate cortex, left ventral posterior cingulate cortex, right splenium of the corpus callosum, right pars triangularis (right inferior frontal gyrus/Broca’s area), and right insular lobe, while connectivity was weaker between the SPL and right superior frontal gyrus (dorsolateral prefrontal cortex).ConclusionPrimary insomnia appears to alter the functional connectivity between the parietal and frontal lobes, cortical structures critical for spatial and verbal working memory.

For the instrument limitation and imperfect imaging optics, it is difficult to acquire high spatial resolution hyperspectral imagery. Low spatial resolution will result in a lot of mixed pixels and greatly degrade the detection and recognition performance, affect the related application in civil and military fields. As a powerful statistical image modeling technique, sparse representation can be utilized to analyze the hyperspectral image efficiently. Hyperspectral imagery is intrinsically sparse in spatial and spectral domains, and image super-resolution quality largely depends on whether the prior knowledge is utilized properly. In this article, we propose a novel hyperspectral imagery super-resolution method by utilizing the sparse representation and spectral mixing model. Based on the sparse representation model and hyperspectral image acquisition process model, small patches of hyperspectral observations from different wavelengths can be represented as weighted linear combinations of a small number of atoms in pre-trained dictionary. Then super-resolution is treated as a least squares problem with sparse constraints. To maintain the spectral consistency, we further introduce an adaptive regularization terms into the sparse representation framework by combining the linear spectrum mixing model. Extensive experiments validate that the proposed method achieves much better results.

Objective: To determine the optimal bone marrow (BM) cell types, and their potential mechanisms of action for neovascularization in chronic ischaemic myocardium. Methods and results:The functional effects, angiogenic potential and cytokine expression of direct intramyocardial implantation of autologous BM CD31-positive endothelial progenitor cells (EPC, n = 9), BM mononuclear cells (MNCs, n = 9), and saline (n = 9) were compared in a swine model of chronic ischaemic myocardium. Autologous BM cells were harvested and catheter-based electromechanical mapping-guided direct intramyocardial injection was performed to target ischaemic myocardium. After 12 weeks, injection of BM-MNC resulted in significant improvements in left ventricular dP / dt (+ 21 ± 8%, P = 0.032), left ventricular pressure (+ 17 ± 4%, P = 0.048) and regional microsphere myocardial perfusion over ischaemic endocardium (+74 ± 28%, P b 0.05) and epicardium (+73 ± 29%, P b 0.05). No significant effects were observed following injection of BM-EPC or saline. Capillary density (1132 ± 69 versus 903 ± 44 per mm 2 , P = 0.047) and expression of mRNA of vascular endothelial growth factor (VEGF, 32.3 ± 5.6 versus 13.1 ± 3.7, P b 0.05,) and angiopoietin-2 (23.9 ± 3.6 versus 13.7 ± 3.1, P b 0.05) in ischaemic myocardium was significantly greater in the BM-MNC group than the saline group. The capillary density in ischaemic myocardium demonstrated a significant positive correlation with VEGF expression (r = 0.61, P b 0.001). Conclusion: Catheter-based direct intramyocardial injection of BM-MNC enhanced angiogenesis more effectively than BM-EPC or saline, possibly via a paracrine effect, with increased expression of VEGF that subsequently improved cardiac performance of ischaemic myocardium.

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