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Introduction: Circular RNAs (circRNAs) are a novel class of widespread non-coding RNAs that may regulate gene expression in eukaryotes. The characterization and function of circRNAs in human cancer remain elusive. The aim of this study was to assess the circRNA profile and identify functional and prognostic significance of circRNA in gastric cancer (GC). Methods: Ribosomal-depleted RNA sequencing and bioinformatic analysis were performed to identify circRNA candidates. Expression of circRNA was examined in paired normal and cancerous gastric tissues. Molecular and cellular techniques were used to explore the biological function and mechanism of circRNA in GC cells. The prognostic significance was analyzed by Kaplan-Meier method and Cox proportional hazards model. Results: We identified at least 5500 distinct circRNA candidates and a series of circRNAs that are differentially expressed in GC tissues compared with matched normal tissues. We further characterized one circRNA derived from the ATXN1 gene, which was termed circATXNl. The expression of circATXNl is often upregulated in GC tissues due to the amplification of its genomic locus. circATXNl may promote cell proliferation by acting as a sponge for members of the miR-15 family. The level of circATXNl was observed as an independent prognostic marker for overall survival and disease-free survival of patients with GC. Conclusions: Our findings suggest that circATXNl is a novel proliferative factor and prognostic marker in gastric cancer. [ABSTRACT FROM AUTHOR]

When testing small size and high density objects with a broad field-of-view (FOV) industrial CT system, multiple objects are always assembled evenly onto the turntable for detecting to improve test efficiency. However, the maximum X-ray’s penetrating path through the materials increases, which means the CT system should collocate with a high energy X-ray source and wide-dynamic range detectors to complete the CT scanning. In this study, we proposed and tested a novel and efficient CT scanning method based on linear-arrangement and synchronous-rotating multi-turntables without enhancing the energy of X-ray source and wide-dynamic range of detectors for the CT system. With this modality, multiple objects are assembled onto multiple synchronous-rotating turntables respectively, and X-rays within the FOV merely penetrate one single object when scanning. The corresponding filtered back projection algorithm for image reconstruction is deduced. The computer simulation and experimental results verified the feasibility of this novel method and the scanning time was reduced to 5–8 minutes when completing the scanning of 3 to 5 group objects. [ABSTRACT FROM AUTHOR]

Directed assembly for nanopatterning on semiconductor surfaces is of interest as a cost-effective approach for lithography on silicon, which is complementary to photolithography. In this work, self-assembly of block copolymers is used to produce nanoscale hexagonal arrays of gold hemispheroids, which are then incorporated into an optically transparent, flexible PDMS stamp. These "plasmonic stamps" can then be used to drive hydrosilylation of alkenes and alkynes on hydride-terminated silicon surfaces upon illumination with low-intensity green light [which corresponds with the absorption of the localized surface plasmon resonance (LSPR) of the gold nanostructures]. The resulting hexagonal arrays of nanoscale alkyl or alkenyl patches mirror the spacing of gold nanoparticles in the parent plasmonic stamp. Close examination of the hydrosilylated patches reveals that they are not continuous across the 20-30 nm diameter patches but instead display an annular motif, which closely resembles the plasmonic electric field (E-field) distribution of the gold hemispheroids embedded within the stamp. The localized surface plasmon appears to drive the hydrosilylation reaction on the silicon surface via formation of electron-hole pairs within the silicon, or injection of hot holes. The yield of hydrosilylation is, however, strongly influenced by the doping of the silicon, and the distance between the plasmonic stamp and the silicon surface. A more nuanced mechanism is thus proposed, involving band bending at the metal-insulator-semiconductor junction, where plasmonically injected/generated holes are swept toward the surface. The accumulation of holes at the silicon surface is the key element of the mechanism, as this step is followed by nucleophilic attack of the alkene or alkyne, to produce the silicon-carbon bond. [ABSTRACT FROM AUTHOR]

At present, there exist two major problems in Angelica sinensis (Oliv.) Diels production in HuiChuan Town producing region, which include breeding and local poor Angelica sinensis processing technology. Lor the breeding and cultivation, there is no professional seed production institutes or company and cultivation areas extend toward low elevation area, which lead to the increase of early bolting rate and degeneration of A. sinensis varieties, severely affecting the quantity and quality of A. sinensis. In regard the processing, the rainy climate in HuiChuan Town producing region has determined that the drying method of A. sinensis after harvest is smoke drying. Although smoke drying is favorable for the drying and preservation of A. sinenis, it consumes a large amount of firewood that causes a high cost, and it shows a poor prevention effect on damages caused by worms in Spring. Thus, traditional burning sulfur fumigation is always adopted for antimoth at the Awakening from Hibernation, which causes the overproof of sulfur dioxide, severely affecting the quality of medicinal materials. To fundamentally solve above problems, concern and effort should be paid on the following aspects: (1) enhancing seedling quality; (2) strengthening the stewardship during cultiva period; (3) strengthening the stewardship during cultivation period; (4) enhancing harvest quality; (5) monitoring breeding quality; (6) monitoring processing quality. Meanwhile, professional industrialized nurseg institutes and the specialty cooperation of farmer must be established for breeding high quality seeds at elevation regions. Moreover, nureg facility conditions should also be improved to ensure the quality of seed seedlings. In conclusion, we can ensure the enhancement of both preseration and processing qualities of A. sinensis, by strengthening the technical training of farmers on processing A. sinensii after harvest, together with the design and construction of large scale facilities for smoking drying. [ABSTRACT FROM AUTHOR]

Aurora A plays a critical role in G2/M transition and mitosis, making it an attractive target for cancer treatment. Aurora A inhibitors showed remarkable antitumor effects in preclinical studies, but unsatisfactory outcomes in clinical trials have greatly limited their development. In this study, the Aurora A inhibitor alisertib upregulated programmed death ligand 1 (PD-L1) expression in a panel of tumor cells both in vitro and in vivo. Upregulation of the checkpoint protein PD-L1 reduced antitumor immunity in immune-competent mice, paradoxically inhibiting the antitumor effects of alisertib. Mechanistically, Aurora A directly bound to and phosphorylated cyclic GMP-AMP synthase (cGAS), suppressing PD-L1 expression in tumor cells. Aurora A inhibition by alisertib activated the cGAS/stimulator of IFN genes (STING)/NF-κB pathway and promoted PD-L1 expression. Combining alisertib with anti-PD-L1 antibody improved antitumor immunity and enhanced the antitumor effects of alisertib in immune-competent mice. Our results, which reveal the immunomodulatory functions of Aurora A inhibitors and provide a plausible explanation for the poor clinical outcomes with their use, offer a potential approach to improve the antitumor efficacy of these inhibitors. [ABSTRACT FROM AUTHOR]

The oriented attachment of inorganic nanocrystals controlled by adsorbed surfactants can lead to the formation of hollow nanoarchitectures with various well-defined morphologies. In this paper, Mg(OH)2hollow nanospheres and the “encapsulated” catanionic vesicles could be simultaneously constructed by using the cationic surfactant of cetyltrimethylammonium hydroxide (CTAOH) and the anionic surfactant of magnesium dodecyl sulfate (Mg(DS)2) as reactants at pH 11.0. Therein, the driven forces for the oriented attachment of Mg(OH)2particles should involve hydrophobic interactions among pendent surfactants. Similarly, the secondary architectures derived from catanionic surfactant−Mg(OH)2hollow nanospheres could also be encountered under nonequilibrium conditions. Interestingly, the coating of Mg(OH)2particles facilitated the direct observation of nanosized surfactant self-assemblies and the membrane fusion without using general staining methods. After the crystalline fusion of coating particles, Mg(OH)2hollow nanospheres and the correspondingly shell-fused superstructures were obtained, implying a simple and versatile method for the study of lipid membranes and the fabrication of M(OH)2(M = divalent metal ions) hollow architectures. [ABSTRACT FROM AUTHOR]

Spectral computed tomography (CT) has a great potential in material identification and decomposition. To achieve high-quality material composition images and further suppress the x-ray beam hardening artifacts, we first propose a one-step material reconstruction model based on Taylor’s first-order expansion. Then, we develop a basic material reconstruction method named material simultaneous algebraic reconstruction technique (MSART). Considering the local similarity of each material image, we incorporate a powerful block matching frame (BMF) into the material reconstruction (MR) model and generate a BMF based MR (BMFMR) method. Because the BMFMR model contains the L0-norm problem, we adopt a split-Bregman method for optimization. The numerical simulation and physical phantom experiment results validate the correctness of the material reconstruction algorithms and demonstrate that the BMF regularization outperforms the total variation and no-local mean regularizations. [ABSTRACT FROM AUTHOR]

The objective of this study is to present and test a new ultra-low-cost linear scan based tomography architecture. Similar to linear tomosynthesis, the source and detector are translated in opposite directions and the data acquisition system targets on a region-of-interest (ROI) to acquire data for image reconstruction. This kind of tomographic architecture was named parallel translational computed tomography (PTCT). In previous studies, filtered backprojection (FBP)-type algorithms were developed to reconstruct images from PTCT. However, the reconstructed ROI images from truncated projections have severe truncation artefact. In order to overcome this limitation, we in this study proposed two backprojection filtering (BPF)- type algorithms named MP-BPF and MZ-BPF to reconstruct ROI images from truncated PTCT data. A weight function is constructed to deal with data redundancy for multi-linear translations modes. Extensive numerical simulations are performed to evaluate the proposed MP-BPF and MZ-BPF algorithms for PTCT in fan-beam geometry. Qualitative and quantitative results demonstrate that the proposed BPF-type algorithms cannot only more accurately reconstruct ROI images from truncated projections but also generate high-quality images for the entire image support in some circumstances. [ABSTRACT FROM AUTHOR]

Background: A new staging system recently proposed by the IGCA has demonstrated a better capacity of stratifying different prognoses for gastric cancer than the 7th edition AJCC staging system (AJCC7). The aim of this study was to evaluate the efficacy of the IGCA system in Chinese patients.Methods: Medical records of patients with gastric cancer who received curative surgery in our center from January 2003 to December 2011 were reviewed retrospectively. All the lesions were staged according to both AJCC7 and IGCA staging systems. Overall survival (OS) of the patients was used as the observation endpoint.Results: One thousand five hundred twenty-six cases were included in this study. By comparing the AJCC7 system with the IGCA systems, 395 cases were stratified into different stages, most of which were in stage III. The IGCA system could better stratify stage IIIB and IIIC patients (5-year OS, 38.1% vs. 29.0%; P = 0.005) than the AJCC7 system (5-year OS, 38.2% vs. 35.9%; P = 0.148). T3N3bM0, T4aN2M0 and T4aN3bM0 made up 97.5% (385/395) of the stage shift. T3N3bM0, which was stratified to stage IIIB in the AJCC7 system, showed a significant poorer prognosis than T4aN2M0 and T4aN3aM0, which were staged to IIIB and IIIC in the same system. The improper staging was revised in the IGCA staging system.Conclusions: The IGCA staging system can stratify stage III gastric cancer patients more properly than the AJCC7 system. [ABSTRACT FROM AUTHOR]

Background: Long noncoding RNAs (lncRNAs) have been shown to play essential roles in almost every important biological process through multiple mechanisms. Although the repertoire of human lncRNAs has rapidly expanded, their biological function and regulation remain largely elusive, calling for a systematic and integrative annotation tool. Results: Here we present AnnoLnc (http://annolnc.cbi.pku.edu.cn), a one-stop portal for systematically annotating novel human lncRNAs. Based on more than 700 data sources and various tool chains, AnnoLnc enables a systematic annotation covering genomic location, secondary structure, expression patterns, transcriptional regulation, miRNA interaction, protein interaction, genetic association and evolution. An intuitive web interface is available for interactive analysis through both desktops and mobile devices, and programmers can further integrate AnnoLnc into their pipeline through standard JSON-based Web Service APIs. Conclusions: To the best of our knowledge, AnnoLnc is the only web server to provide on-the-fly and systematic annotation for newly identified human lncRNAs. Compared with similar tools, the annotation generated by AnnoLnc covers a much wider spectrum with intuitive visualization. Case studies demonstrate the power of AnnoLnc in not only rediscovering known functions of human lncRNAs but also inspiring novel hypotheses. [ABSTRACT FROM AUTHOR]

Fatty acid synthase (FAS) and human epidermal growth factor receptor 2 (HER2) are overexpressed in gastric cancer (GC), and certain interactions have been found between FAS and HER2. A total of 94 patients were enrolled in the present study, each of whom underwent a D2 radical surgery in Zhongshan Hospital affiliated with Fudan University (Shanghai, China) between 2000 and 2005. The expression of FAS and HER2 was assessed by immunohistochemistry analysis of tissue microarrays generated from GC and non-tumor tissues. All data were analyzed by GraphPad Prism 5.0 to investigate the association between FAS and HER2 and to detect the potential association with prognosis. FAS (P<0.0001) and membranous HER2 (mHER2; P=0.0021) were overexpressed in the GC tissues, and a bidirectional and strong correlation was demonstrated between FAS and mHER2 in the tumor tissues. The expression of cytoplasmic HER2 (cHER2) was significantly lower in the GC tissues compared with the non-tumor tissues (P=0.0005), and cHER2 was expressed at a higher level in tumors that had better differentiation compared with poorly-differentiated tissues (P=0.0503). Patients with a concordant expression pattern of FAS and mHER2 showed a significantly poorer prognosis than the non-concordant group (P=0.0096; hazards ratio, 3.2801; 95% confidence interval, 1.5781-6.8176). GC tissues significantly overexpress FAS and mHER2 and the expression of these two markers is associated. Patients with a concordant expression of FAS and mHER2 are more likely to suffer a poor prognosis. [ABSTRACT FROM AUTHOR]

In this paper, the synthesized surfactant of copper dodecyl sulfate (Cu(DS)2) was used as a special metal-ion source for the morphological control of copper oxide (CuO) architectures. During the fabrication processes, the ribbon-shaped intermediates of basic copper salt with lamellar structures were observed at 60.0 °C for the first time. In the absence or presence of dodecanol (DOH), Cu(DS)2could react with sodium hydroxide to form dumbbell-like architectures of CuO nanoparticles. The incorporation of DOH molecules into the adsorption monolayers of surfactant ions could greatly enlarge the dumbbell size in length, probably depending upon the formation of the DOH−DS complex. These indicated that the template effectiveness of the intermediate ribbons, together with the hydrophobic interactions of adsorbed hydrocarbon chains, should account for the formation process of CuO dumbbells. Interestingly, the addition of sodium chloride into the reaction systems could induce the morphological change of CuO dumbbells to the twin-anchors and then to the twin-spheres with two holes in the center. This further suggests that the hydrophobic interaction of pendent hydrocarbon chains provides an important approach for material fabrication purposes. [ABSTRACT FROM AUTHOR]

Lyotropic liquid crystalline phases have immediate relevance in biology because of the prevalence of organized lipid structures in living systems. The incorporation of hydrophilic reagents in water domains with well-defined nanoscale geometry favors the construction of nanostructured materials of inorganics, and/or the inorganic−organic hybrids. In this paper, the lamellar mesophases composed of calcium dodecyl sulfate (CDS), n-pentanol, and ammonia (5 wt% NH 3·H 2O in water) were constructed and used as the precipitation media of calcium carbonate (CaCO 3). Under the atmosphere of carbon dioxide gas, the occurring solid−liquid−gas reaction resulted only in rhombohedral calcite particles at the beginning, then ultimately in layer-cake aggregates of calcite and stick-bundle aggregates of aragonite. Furthermore, the aragonite content increased with the proceeding time interval of the three-phase reaction, indicating a special crystallization habit of CaCO 3in the lamellar mesophases of CDS. Aside from these, the influence of the structure of CDS lamellar mesophases on the formation of CaCO 3crystals is also discussed. These imply an effective biomimetic approach for the simultaneous fabrication of metastable aragonite and thermodynamically stable calcite under mild conditions. [ABSTRACT FROM AUTHOR]

Spectral computed tomography (CT) reconstructs the same scanned object from projections of multiple narrow energy windows, and it can be used for material identification and decomposition. However, the multi-energy projection dataset has a lower signal-noise-ratio (SNR), resulting in poor reconstructed image quality. To address this thorny problem, we develop a spectral CT reconstruction method, namely spatial-spectral cube matching frame (SSCMF). This method is inspired by the following three facts: (i) human body usually consists of two or three basic materials implying that the reconstructed spectral images have a strong sparsity; (ii) the same basic material component in a single channel image has similar intensity and structures in local regions. Different material components within the same energy channel share similar structural information; (iii) multi-energy projection datasets are collected from the subject by using different narrow energy windows, which means images reconstructed from different energy-channels share similar structures. To explore those information, we first establish a tensor cube matching frame (CMF) for a BM4D denoising procedure. Then, as a new regularizer, the CMF is introduced into a basic spectral CT reconstruction model, generating the SSCMF method. Because the SSCMF model contains an L0-norm minimization of 4D transform coefficients, an effective strategy is employed for optimization. Both numerical simulations and realistic preclinical mouse studies are performed. The results show that the SSCMF method outperforms the state-of-the-art algorithms, including the simultaneous algebraic reconstruction technique, total variation minimization, total variation plus low rank, and tensor dictionary learning. [ABSTRACT FROM AUTHOR]

A theoretically exact backprojection filtration algorithm is proved and implemented for image reconstruction from a multi-segment linear trajectory assuming fan-beam geometry. The reconstruction formula is based on a concept of linear PI-line (L-PI) proposed in our previous work. The proof is completed in two consecutive steps. In the first step, it is proved that theoretically exact image reconstruction can be obtained on an arbitrary L-PI line from an infinite straight-line trajectory. In the second step, it is shown that accurate image reconstruction can be achieved from a multi-segment line trajectory by introducing a weight function to deal with the data redundancy. Numerical implementation and simulation results validate the correctness of our theoretical results. [ABSTRACT FROM AUTHOR]