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ObjectiveEsophagogastroduodenoscopy (EGD) is the pivotal procedure in the diagnosis of upper gastrointestinal lesions. However, there are significant variations in EGD performance among endoscopists, impairing the discovery rate of gastric cancers and precursor lesions. The aim of this study was to construct a real-time quality improving system, WISENSE, to monitor blind spots, time the procedure and automatically generate photodocumentation during EGD and thus raise the quality of everyday endoscopy.DesignWISENSE system was developed using the methods of deep convolutional neural networks and deep reinforcement learning. Patients referred because of health examination, symptoms, surveillance were recruited from Renmin hospital of Wuhan University. Enrolled patients were randomly assigned to groups that underwent EGD with or without the assistance of WISENSE. The primary end point was to ascertain if there was a difference in the rate of blind spots between WISENSE-assisted group and the control group.ResultsWISENSE monitored blind spots with an accuracy of 90.40% in real EGD videos. A total of 324 patients were recruited and randomised. 153 and 150 patients were analysed in the WISENSE and control group, respectively. Blind spot rate was lower in WISENSE group compared with the control (5.86% vs 22.46%, p<0.001), and the mean difference was −15.39% (95% CI −19.23 to −11.54). There was no significant adverse event.ConclusionsWISENSE significantly reduced blind spot rate of EGD procedure and could be used to improve the quality of everyday endoscopy.Trial registration numberChiCTR1800014809; Results.

Aberrant expression of miR-196a has been frequently reported in cancer studies. However, the expression and mechanism of its function in gastric cancer remains unclear. Quantitative real-time PCR was carried out to detect the relative expression of miR-196a in gastric cancer cell lines and tissues. SGC7901 cells were treated with miR-196a inhibitors, mimics, or pCDNA/miR-196a to investigate the role of miR-196a in cell proliferation. Higher expression of miR-196a in gastric cancer tissues was associated with tumor size, a higher clinical stage, and was also correlated with shorter overall survival of patients with gastric cancer. Exogenous downregulation of miR-196a expression significantly suppressed the in vitro cell-cycle progression, proliferation, and colony formation of gastric cancer cells, and ectopic miR-196a expression significantly enhanced the development of tumors in nude mice. Luciferase assays revealed that miR-196a inhibited p27 kip1 expression by targeting one binding site in the 3 0 -untranslated region (3 0 -UTR) of p27 kip1 mRNA. qPCR and Western blot assays verified that miR-196a reduced p27 kip1 expression at both mRNA and protein levels. The p27 kip1 -mediated repression in cell proliferation was reverted by exogenous miR-196a expression. A reverse correlation between miR-196a and p27 kip1 expression was noted in gastric cancer tissues. Our study shows that aberrant overexpression of miR-196a and consequent downregulation of p27 kip1 could contribute to gastric carcinogenesis and would be targets for gastric cancer therapies and further developed as potential prognostic factors.

Novel flowerlike nanostructures consisting of Cu 2 O nanopetals were successfully synthesized by a facile wet chemical method for the first time. The synthesized products were systematically studied by X-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the nucleation and growth of the nanoflowers were governed by a nucleation-dissolution-recrystallization growth mechanism. It is noteworthy that the initially formed Cu 2 O nanoparticles without addition of NaOH were crucial to the growth of the final nanoarchitectures. A UV-vis spectrum was used to estimate the band gap energies of the nanoflowers. Further control experiments were also carried out to investigate the factors that impact the morphology and size of the products. It was demonstrated that the concentrations of NaOH and cetyltrimethylammonium bromide (CTAB) play key roles in the formation of the as-synthesized nanoflowers. By adjusting the concentration of NaOH and CTAB, temperature, and the quantity of water, Cu 2 O micrograss, nanorods, and pricky microrods can be synthesized accordingly. Our stepwise synthetic method may shed some light on the design of other well-defined complex nanostructures.

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BackgroundNoninvasive cardiovascular magnetic resonance (CMR) techniques including arterial spin labeling (ASL), blood oxygenation level-dependent (BOLD), and intravoxel incoherent motion (IVIM), are capable of measuring tissue perfusion-related parameters. We sought to evaluate and compare these three CMR techniques in characterizing skeletal muscle perfusion in lower extremities and to investigate their abilities to diagnose and assess the severity of peripheral arterial disease (PAD).MethodsFifteen healthy young subjects, 14 patients with PAD, and 10 age-matched healthy old subjects underwent ASL, BOLD, and IVIM CMR perfusion imaging. Healthy young and healthy old participants were subjected to a cuff-induced ischemia experiment with pressures of 20 mmHg and 40 mmHg above systolic pressure during imaging. Perfusion-related metrics, including blood flow, T2* relaxation time, perfusion fraction f, diffusion coefficient D, and pseudodiffusion coefficient D*, were measured in the anterior, lateral, soleus, and gastrocnemius muscle groups. Friedman, Mann-Whitney, Wilcoxon signed rank, and Spearman rank correlation tests were used for statistical analysis.ResultsIn cases of significant differences determined by the Friedman test (P < 0.05), blood flow, T2*, and D values gradually decreased, while f values showed a tendency to increase in healthy subjects under cuff compression. No significant correlations were found among the ASL, BOLD, and IVIM parameters (all P > 0.05). Blood flow and T2* values showed significant positive correlations with transcutaneous oxygen pressure measurements (ρ = 0.465 and 0.522, respectively; both P ≤ 0.001), while f values showed a significant negative correlation in healthy young subjects (ρ = − 0.351; P = 0.018). T2* was independent of age in every muscle group. T2* values were significantly decreased in PAD patients compared with healthy old subjects and severe PAD patients compared with mild-to-moderate PAD patients (all P < 0.0125). Significant correlations were found between T2* and ankle–brachial index values in all muscle groups in PAD patients (ρ = 0.644–0.837; all P < 0.0125). Other imaging parameters failed to show benefits towards the diagnosis and disease severity evaluation of PAD.ConclusionsASL, BOLD, and IVIM provide complementary information regarding tissue perfusion. Compared with ASL and IVIM, BOLD may be a more reliable technique for assessing PAD in the resting state and could thus be applied together with angiography in clinical studies as a tool to comprehensively assess microvascular and macrovascular properties in PAD patients.Electronic supplementary materialThe online version of this article (10.1186/s12968-018-0441-3) contains supplementary material, which is available to authorized users.

MR Radiomics based on cervical lesions from one single scanner has achieved promising results. However, it is a challenge to achieve clinical translation. Considering multi-scanners and non-uniform scanning parameters from different centers in a real-world medical scenario, we should first identify the influence of such conditions on the robustness of MR radiomics features (RFs) based on the female cervix. In this study, 9 healthy female volunteers were enrolled and 3 kiwis were selected as references. Each of them underwent T2 weighted imaging in three different 3.0-T MR scanners with uniform acquisition parameters, and in one MR scanner with various scanning parameters. A total of 396 RFs were extracted from their images with and without decile intensity normalization. The RFs’ reproducibility was evaluated by coefficient of variation (CV) and quartile coefficient of dispersion (QCD). Representative features were selected using the hierarchical cluster analysis and their discrimination abilities were estimated by ROC analysis through retrospective comparison with the junctional zone and the outer muscular layer of healthy cervix in patients (n = 58) with leiomyoma. This study showed that only a few RFs were robust across different MR scanners and acquisition parameters based on females’ cervix, which might be improved by decile intensity normalization method.