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Background Coronary distensibility index (CDI), as an early predictor of cardiovascular diseases, has the potential to complement coronary computed tomography angiography (cCTA)-derived fractional flow reserve (CT-FFR) for predicting major adverse cardiac events (MACEs). Thus, the prognostic value of CT-FFR combined with CDI for MACEs is worth exploring. Methods Patients with a moderate or severe single left anterior descending coronary artery stenosis were included and underwent FFR and CDI analysis based on cCTA, followed up at least 1 year, and recorded MACEs. Multivariate logistic regression analysis was performed to determine independent predictors of MACEs. The area under of receiver operating characteristic (ROC) curve was used to evaluated evaluate the diagnostic performance of CT-FFR, CDI, and a combination of the two. Results All the vessel-specific data were from LAD. 150 patients were analysed. 55 (37%) patients experienced MACEs during follow-up. Patients with CT-FFR ≤ 0.8 had higher percentage of MACEs compared with CT-FFR > 0.8 (56.3% vs.7.3%, p p p = 0.025), triglyceride (p = 0.015), CT-FFR ≤ 0.80 (p = 0.038), and CDI (p p = 0.0002). Conclusion Our study provides initial evidence that combining CDI with CT-FFR shows incremental discriminatory power for MACEs over CT-FFR alone, independent of clinical risk factors. Diabetes and triglyceride are also associated with MACEs.

Objective This paper proposes a new photoacoustic computed tomography (PACT) imaging system employing dual ultrasonic transducers with different frequencies. When imaging complex biological tissues, photoacoustic (PA) signals with multiple frequencies are produced simultaneously; however, due to the limited bandwidth of a single-frequency transducer, the received PA signals with specific frequencies may be missing, leading to a low imaging quality. Methods In contrast to our previous work, the proposed system has a compact volume as well as specific selection of the detection center frequency of the transducer, which can provide a comprehensive range for the detection of PA signals. In this study, a series of numerical simulation and phantom experiments were performed to validate the efficacy of the developed PACT system. Results The images generated by our system combined the advantages of both high resolution and ideal brightness/contrast. Conclusion The interchangeability of transducers with different frequencies provides potential for clinical deployment under the circumstance where a single frequency transducer cannot perform well.

The surface modification of polyacrylonitrile (PAN) fibers with boric acid was utilized to modulate the homogeneity of the radial structure of the PAN fibers during thermal stabilization. Exothermic peaks of the fibers were put off by boric acid, and unreacted nitrile groups of the oxidized PAN fibers increased with the boron content, indicating that boric acid on the fiber surface had an retardant effect on the thermal stabilization of PAN fibers. The relative skin thicknesses of the oxidized PAN fibers were quantitatively measured by sulfuric acid etching and SEM observation. The value increased obviously with the boron content, which could be further elevated by increasing stabilization time or decreasing stabilization temperature. Oxidized PAN fibers with more homogeneous radial structure can thus be obtained with the modification of boric acid, which might be beneficial for the preparation of high performance carbon fibers.

Background Vein graft restenosis (VGR), which appears to be caused by dyslipidemia following vascular transplantation, seriously affects the prognosis and long-term quality of life of patients. Methods This study analyzed the genetic data of restenosis (VGR group) and non-stenosis (control group) vessels from patients with coronary heart disease post-vascular transplantation and identified hub genes that might be responsible for its occurrence. GSE110398 was downloaded from the Gene Expression Omnibus database. A repeatability test for the GSE110398 dataset was performed using R language. This included the identification of differentially expressed genes (DEGs), enrichment analysis via Metascape software, pathway enrichment analysis, and construction of a protein–protein interaction network and a hub gene network. Results Twenty-four DEGs were identified between VGR and control groups. The four most important hub genes ( KIR6.1, PCLP1, EDNRB, and BPI) were identified, and Pearson’s correlation coefficient showed that KIR6.1 and BPI were significantly correlated with VGR. KIR6.1 could also sensitively predict VGR (0.9 Conclusion BPI and KIR6.1 were differentially expressed in vessels with and without stenosis after vascular transplantation, suggesting that these genes or their encoded proteins may be involved in the occurrence of VGR.

Large burst activity, identified as toroidal Alfvén eigenmode (TAE) avalanche, occurs frequently in neutral-beam heated plasmas in National Spherical Torus Experiment (NSTX). Based on the typical experimental observation of TAE avalanche on NSTX, a self-consistent nonlinear multiple wave-number (k ∥ ≃ n/R, where n toroidal mode-number and R major radius) simulation associated with TAE avalanches is performed using the experimental parameters and profiles before the occurrence of TAE avalanche as the M3D-K input. The wave–wave nonlinear coupling among different modes and the resonant interaction between different modes and energetic-ions during TAE avalanches are identified in the nonlinear multiple wave-number simulations. The resonance overlap during the TAE avalanche is clearly observed in the simulation. It is found that the effective wave–wave coupling and a sufficiently strong drive are two important ingredients for the onset of TAE avalanches. TAE avalanche is considered to be a strongly nonlinear process and it is always accompanied by the simultaneous rapid frequency-chirping and large amplitude bursting of multiple modes and significant energetic-ion losses. The experimental phenomenon is observed on NSTX and is qualitatively reproduced by the simulation results in this work. These findings indicate that the onset of avalanche is triggered by nonlinearity of the system, and are also conducive to understanding the underlying mechanism of avalanche transport of energetic particles in the future burning plasmas, such as International Thermonuclear Experiment Reactor.

Background: Glioma, as the most common aggressive malignant tumor in the central nervous system, is still an insurmountable disease in neural system. The potential mechanism of its carcinogenesis remains largely unclear. Methods: In the present study, we identified dysregulated lncRNA solute carrier family 8 member A1 antisense RNA 1 (SLC8A1-AS1) as associated with glioma based on The Cancer Genome Atlas （TCGA）data. Validation experiment was conducted to confirm a high expression level of lncRNA SLC8A1-AS1 in glioma tissues. Results: Down-regulation of lncRNA SLC8A1-AS1 suppressed proliferation, clone formation, migration and invasion of glioma cells in vitro and in vivo. Moreover, lncRNA SLC8A1-AS1 silencing decreased the activity of the Wnt/β-catenin pathway and suppressed the epithelial to mesenchymal transition (EMT) in glioma cells. Conclusions: Collectively, these findings provide a novel insights into the function and mechanism of lncRNA SLC8A1-AS1 in the pathogenesis of glioma and highlight its potential as a therapeutic target for glioma intervention.

Background We studied the characteristics and regularity of appropriate insertion points for percutaneous pedicle screw placement in the lumbar spine using C-arm X-ray fluoroscopy. The purpose of this study was to improve the accuracy of percutaneous pedicle screw placement and reduce the incidence of superior-level facet joint violation. Methods Six normal spinal specimens were included. Three different methods for placing percutaneous pedicle screws in the lumbar spine were applied, including the Roy-Camille method, Magerl method and Weinstein method. The relationships among the insertion point, pedicle projection and proximal facet joint on C-arm X-ray films were studied. The projection morphology of the vertebral pedicle in different segments of the lumbar spine was observed. The relationship between the outer edge of the pedicle projection and the outer edge of the cranial articular process was also studied. The distance between the insertion point and the facet joint (M1), the distance between the insertion point and outer edge of the cranial articular process (M2), and the distance between the insertion point and the projection center of the pedicle (M) were measured. Results In this study, we found that the projection shape of the vertebral pedicle differed across segments of the lumbar spine: the shape for L1-L3 was oval, and that for L4-L5 was round. The radiographic study showed that the outer edge of the cranial articular process was located on the lateral side of the outer edge of the pedicle projection and did not overlap with the pedicle projection. M for the Weinstein group was larger than that for the Roy-Camille group (P P Conclusion Under C-arm X-ray fluoroscopy, we were able to accurately identify the characteristics and regularity of the appropriate insertion point for percutaneous pedicle screw placement in the lumbar spine, which was important for improving the accuracy of percutaneous pedicle screw placement and reducing the incidence of superior-level facet joint violation.

A full understanding of RNA-mediated biology would require the knowledge of three-dimensional (3D) structures, structural flexibility and stability of RNAs. To predict RNA 3D structures and stability, we have previously proposed a three-bead coarse-grained predictive model with implicit salt/solvent potentials. In this study, we will further develop the model by improving the implicit-salt electrostatic potential and involving a sequence-dependent coaxial stacking potential to enable the model to simulate RNA 3D structure folding in divalent/monovalent ion solutions. As compared with the experimental data, the present model can predict 3D structures of RNA hairpins with bulge/internal loops (, 24 pages,8 figures

The N-myc downstream regulated gene (Ndrg) family consists of four main members Ndrg1, 2, 3, and 4. The Ndrg genes are involved in many vital biological events including development. However, comprehensive expression patterns of this gene family during vertebrate embryogenesis remain largely unknown. Here, we analyzed the Ndrg family from the evolutionary perspective and examined the expression patterns of the Ndrg genes during Xenopus tropicalis embryogenesis. Different Ndrg family members of vertebrates are separated into different homology clusters which can be further classified into two groups and each Ndrg family member is well conserved during evolution. The temporal and spatial expression patterns of Ndrg1, 2, 3 and 4 are different during early Xenopus tropicalis development. Ndrg1, 2 and 4 are maternally expressed genes while Ndrg3 is a zygotically expressed gene. The Ndrg genes are differentially expressed in the developing central nervous system, the developing sensory organs, and the developing excretory organs. Moreover, they also show other specific expression domains. Our results indicate that the Ndrg genes exhibit specific expression patterns and may play different roles during vertebrate embryogenesis.

We characterized the genomic structure and developmental expression of the Dleu7 (deleted in lymphocytic leukemia, 7) gene in Xenopus tropicalis and the evolution of the gene across species. Within the protein-coding sequence (CDS) region, X. tropicalis Dleu7 consists of two exons and one intron. However, bioinformatic analysis indicates that this 211-amino-acid protein contains no obvious functional domains or known motifs. Reverse-transcription polymerase chain reaction and whole-mount in situ hybridization results revealed that, in addition to its expression in the blood island region, some regions of the central nervous system, and subdomains of the neural tube, X. tropicalis Dleu7 is zygotically expressed primarily in mesoderm tissues such as notochord and muscles during early embryogenesis. Expression in notochord is consistent with results from genome-wide association studies suggesting that DLEU7 is related to human adult height. Expression in the blood island region, where blood cell precursors (including B cells) are generated, implies a potential conserved role for Dleu7 in B-cell development between amphibians and mammals. Expression of Dleu7 in some regions of the central nervous system and subdomains of the neural tube also suggests other functions in development. Phylogenetic analysis indicated that Dleu7 is a vertebrate-specific gene and undergoes strong selective pressure in lower vertebrates but is functionally constrained in higher mammals. When subcellular localization was examined by overexpression of enhanced green fluorescent protein fusion protein, Dleu7 showed centrosome localization with main distribution in cytoplasm. Treating gastrula embryos with SU5402, a small molecular inhibitor of the fibroblast growth factor (FGF) receptor, confirmed that Dleu7 expression in mesoderm is regulated by FGF signaling. Our data provide important clues for pathogenesis and physiology during development from the perspective of evolutionary conservation.

Ion-mediated interaction is important for the properties of polyelectrolytes such as colloids and nucleic acids. The effective pair interactions between two polyelectrolytes have been investigated extensively, but the many-body effect for multiple polyelectrolytes still remains elusive. In this work, the many-body effect in potential of mean force (PMF) between like-charged nanoparticles in various salt solutions has been comprehensively examined by Monte Carlo simulation and the nonlinear Poisson-Boltzmann theory. Our calculations show that, at high 1:1 salt, the PMF is weakly repulsive and appears additive, while at low 1:1 salt, the additive assumption overestimates the repulsive many-body PMF. At low 2:2 salt, the pair PMF appears weakly repulsive while the many-body PMF can become attractive. In contrast, at high 2:2 salt, the pair PMF is apparently attractive while the many-body effect can cause a weaker attractive PMF than that from the additive assumption. Our microscopic analyses suggest that the elusive many-body effect is attributed to ion-binding which is sensitive to ion concentration, ion valence, number of nanoparticles and charges on nanoparticles., 12 pages, 6 figures

With the rapid expansion of hydropower projects, Construction safety problem has become one of the bottlenecks for the development of hydropower industry. Combined with the construction of the diversion channel project of Guan Yinyan hydropower station, from the point of view of construction traffic safety, based on the result of the FAHP model, factors which influence the construction safety of the diversion channel project of Guan Yinyan hydropower station have been found, relative measures focuses on the approach to eliminate hazards and guarantee construction safety have been elaborated.

Ion-mediated interaction is critical to the structure and stability of nucleic acids. Recent experiments suggest that the multivalent ion-induced aggregation of double-stranded (ds) RNAs and DNAs may strongly depend on the topological nature of helices, while there is still lack of an understanding on the relevant ion-mediated interactions at atomistic level. In this work, we have directly calculated the potentials of mean force (PMF) between two dsRNAs and between two dsDNAs in Cobalt Hexammine ion (Co-Hex) solutions by the atomistic molecular dynamics simulations. Our calculations show that at low [Co-Hex], the PMFs between B-DNAs and between A-RNAs are both (strongly) repulsive.However, at high [Co-Hex], the PMF between B-DNAs is strongly attractive, while those between A-RNAs and between A-DNAs are still (weakly) repulsive. The microscopic analyses show that for A-form helices, Co-Hex would become internal binding into the deep major groove and consequently cannot form the evident ion-bridge between adjacent helices, while for B-form helices without deep grooves, Co-Hex would exhibit external binding to strongly bridge adjacent helices. In addition, our further calculations show that, the PMF between A-RNAs could become strongly attractive either at very high [Co-Hex] or when the bottom of deep major groove is fixed with a layer of water.

BACKGROUND The aim of this study was to refine clinical risk factor stratification and make an optimal intervention plan to prevent ischemic stroke. MATERIAL/METHODS Clinical data, including diffusion-weighted imaging (DWI) findings, were collected in a cohort of hospitalized transient ischemic attack (TIA) patients from January 2010 to December 2011. Recurrent cerebrovascular events after TIA, including recurrent TIA, minor stroke, and major stroke, were identified by face-to-face follow-up. A multivariate, ordinal, logistic regression model was used to determine significant predictors of recurrent events. RESULTS Of 106 TIA patients, 24 (22.6%) had recurrent TIA and 20 (18.9%) had a stroke within 7 days. Hypertension, dyslipidemia, a history of ischemic stroke or TIA, and ABCD2 score were significantly associated with the recurrent events after TIA (P

In statistical signal processing, the sequential Monte Carlo (SMC) method is powerful and can approach the theoretical optima. However, its computational complexity is usually very high, especially in multiple-input multiple-output (MIMO) systems. This paper presents a new low-complexity SMC (LC-SMC) algorithm for blind detection in MIMO systems, the main idea of which is to shrink the sampling space via channel estimation which is initialized using the first differentially modulated symbol and then updated using the Monte Carlo samples. Since the a posteriori probability of the transmitted symbols can be calculated separately by each transmit antenna, the proposed LC-SMC algorithm is not only computationally efficient, as compared to the original SMC whose complexity grows exponentially with the number of transmit antennas, but also makes blind turbo receiver more feasible for multilevel/phase modulations. Simulation results are presented to demonstrate the effectiveness of the LC-SMC algorithm

Blind source separation (BSS) aims at recovering statistically independent source signals from their linear mixtures without knowing the mixing coefficients. Besides independent component analysis, nonlinear principal component analysis (NPCA) is shown to be another useful tool for solving this problem, but it requires that the measured data be prewhitened. By taking into account the autocorrelation matrix of the measured data, we present in this paper a modified NPCA criterion, and develop a least-mean-square (LMS) algorithm and a recursive least-squares algorithm. They can perform the online BSS using directly the unwhitened observations. Since a natural gradient learning is applied and the prewhitening process is removed, the proposed algorithms work more efficiently than the existing NPCA algorithms, as verified by computer simulations on man-made sources as well as practical speech signals

Synaptophysin (SYP) is a synaptic vesicle membrane protein and involved in the release of neurotransmitters, synaptic plasticity, and formation and recycling of synaptic vesicles. SYP may serve as a specific marker of synaptic proteins. Our results showed high glucose and hypoxia could significantly impair the intelligence and the SYP level was positively related to the degree of intelligence in animals. Ubiquitination may influence the SYP expression. In our study, an ubiquitination inhibitor (MG-132) was injected intraperitoneally. Results showed this could increase SYP expression in the brain to improve the intelligent drop due to high glucose and hypoxia in animals. SYP ubiquitination is closely associated with E3 ubiquitin ligase, a mammalian homologue of seven in absentia. In our study, lentivirus expressing siah shRNA was injected into the cerebral ventricle to down-regulate siah expression, and results showed the SYP expression in the brain increased markedly. In addition, we also found that VitK3 could increase the SYP expression in the brain to improve the intelligent drop due to high glucose and hypoxia.

Yellow needle-shaped crystals of the title compound, {[Ag(C30H22N4)][Ag(NO3)2]}n, were obtained by the reaction of AgNO3and 9,10-bis(benzimidazol-1-ylmethyl)anthracene (L) in a 2:1 ratio. The asymmetric unit consists of two AgIcations, one halfLligand and one nitrate anion. One AgIcation occupies a crystallographic inversion centre and links two N-atom donors of two distinctLligands to form an infinite one-dimensional coordination polymer. The second AgIcation lies on a crystallographic twofold axis and is coordinated by two O-atom donors of two nitrate anions to form an [Ag(NO3)2]−counter-ion. The polymeric chains are linked into a supramolecular frameworkviaweak Ag...O [3.124 (5) Å] and Ag...π (2.982 Å) interactions (π is the centroid of an outer anthracene benzene ring). The π interactions contain two short Ag...C contacts [2.727 (6) and 2.765 (6) Å], which can be considered to define Ag–η2-anthracene bonding interactions. In comparison with a previously reported binuclear AgIcomplex [Du, Hu, Zhang, Zeng & Bu (2008).CrystEngComm,10, 1866–1874], this new one-dimensional coordination polymer was obtained by changing the metal–ligand ratio during the synthesis.

OBJECTIVE: This study aimed to investigate the influence of low-dose levodopa (L-DOPA) on neuronal cell death under oxidative stress. METHODS: PC12 cells were treated with L-DOPA at different concentrations. We detected the L-DOPA induced reactive oxygen species (ROS). Meanwhile, MTT and LDH assay were performed to determine the proliferation and growth of PC12 cells with or without ROS scavenger. In addition, after pretreatment with L-DOPA at different concentrations alone or in combination with CD39 inhibitor, PC12 cells were incubated with hydrogen peroxide (H2O2) and the cell viability was evaluated by MTT and LDH assay. In addition, the expression of pCREB and CD39 was detected by immunofluorescence staining and Western blot assay in both cells and rat's brain after L-DOPA treatment. RESULTS: After treatment with L-DOPA for 3 days, the cell proliferation and growth were promoted when the L-DOPA concentration was 30 µM. Low dose L-DOPA could protect the PC12 cells from H2O2 induced oxidative stress, which was compromised by CD39 inhibitor. In addition, the expression of CD39 and pCREB increased in both PC12 cells and rats' brain after L-DOPA treatment. CONCLUSIONS: L-DOPA at different concentrations has distinct influence on proliferation and growth of PC12 cells, and low dose (

A 10-year-old girl was admitted with cough and palpitation, a transthoracic and transoesophageal echocardiography showed anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). A computed tomographic scan demonstrated an enormously dilated, tortuous, and dominant right coronary artery originating from the right coronary cusp, with a large number of collateral vessels filling the left main coronary artery (LMCA) ( Panels A …

This paper studies the joint estimation problem of ranges, DOAs, and frequencies of near-field narrowband sources and proposes a new computationally efficient algorithm, which employs a symmetric uniform linear array, uses eigenvalues together with the corresponding eigenvectors of two properly designed matrices to estimate signal parameters, and does not require searching for spectral peak or pairing among parameters. In addition, the proposed algorithm can be applied in arbitrary Gaussian noise environment since it is based on the fourth-order cumulants, which is verified by extensive computer simulations.