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Lilii Bulbus is a folk medicine for both culinary and medicinal purpose. In traditional medicine theory, Lilii Bulbus is usually used as an complementary therapy for nourishing the heart and lung, clearing heat in the treatment of mental instability and depression. In this study, NLPS-1a (Mw = 2610 Da, DP = 16), a water-soluble non-starch Lilii Bulbus polysaccharides, was isolated and purified. Structural analysis showed that NLPS-1a mainly contained Man and Glc with a molar ratio of 11.137 and 9.427. The glycosidic linkages of NLPS-1a were 1,3-Manp (59.93%), 1,2-Glcp (37.93%), T-Glcp (1.21%) and T-Manp (0.93%), indicating the highly-linear structures. In addition, NLPS-1a could significantly repair the injury of PC12 cells induced by corticosterone (CORT), reduce Lactate dehydrogenase (LDH) leakage and decrease the cell apoptosis in a dose-dependent manner. Above all, the results indicated that NLPS-1a had protective effects against CORT-induced neurotoxicity in PC12 cells, and might be a natural antidepressant, which enriched the study of the metabolic mechanism between herbal polysaccharides and antidepressant. [ABSTRACT FROM AUTHOR]

Forced degradation studies aim to systemically characterize the degradation products of an active pharmaceutical ingredient (API) and its formulations under harsh conditions that accelerate degradation. These studies are especially valuable for sustained-release products in selecting appropriate packaging materials and storage conditions in the field of pharmaceutics. To demonstrate the degradation pathways and degradation products of the API and products, mass spectrometry is used for further characterization of the degradation products. Goserelin acetate sustained-release implant, which is prepared by hot melt extrusion using biodegradable material polylactic acid-glycolic acid copolymer as a carrier, is used for the treatment of early breast cancer in premenopausal and perimenopausal women. In this study, a simple and sensitive high-performance chromatography method was established following the ICH guidance. We conducted forced degradation experiments to determine the conditions of the product. The forced degradation studies of the goserelin acetate sustained-release implant showed the presence of a single impurity during thermal degradation, as observed in the HPLC analysis. To elucidate the structure of the impurity and characterize its degradation pathway, we performed further characterization using LC–MS. [ABSTRACT FROM AUTHOR]

Introducing superconductivity into two-dimensional (2D) films with nontrivial topology has been intensively pursued as one of the feasible scenarios to realize 1D topological superconductor. Prevailing endeavors mostly exploit the external gating or proximity effect of a traditional superconductor, by which the critical temperatures ( T c ) are limited to several Kelvin range. Here, we report on the discovery of interface-enhanced superconductivity in monolayer 1T′-MoTe2 film. A thermally driven phase transition from Mo6Te6 nanowires to 1T′-MoTe2 films, grown on SrTiO3(001) surface by the molecular beam epitaxial methods, is demonstrated. A combined study of scanning tunneling microscopy/spectroscopy, electrical transport and magnetization measurements indicates the T c of MoTe2 film is around 30 K, two orders of magnitude larger than its 3D counterpart crystal. This study shows that interfacial engineering is an efficient way to tune monolayer 1T′-MoTe2 film into superconducting states, and thus may pave the way toward higher- T c 1D intrinsic topological superconductivity. [ABSTRACT FROM AUTHOR]

Aluminum-steel hybrid structures have great application prospects in lightweight vehicles. In this study, AA6061-T6 and SS304 with 3 mm thickness and 10 mm lap width were welded-brazed by Cold Metal Transfer process. Both electric parameters and droplets transfer were monitored. An improved discretization method was employed to calculate the equivalent welding parameters. Macro and microstructures were characterized by OM, SEM with EDS and XRD, and the tensile-shear strength, Vickers and nanohardness were measured to evaluate the mechanical properties of the joints. CMT welding process is a short-circuit transfer mode with one pulse one droplet. With the increase in heat input, welding cycle and interfacial layer thickness increased. Al9Fe2Si2 and FeAl5 or FeAl3 were found in the interfacial reaction zone. The intermetallic compounds whose hardness is 1.7 times of SS304 are the main reason for the fracture failure to appear at the interfacial layer. [ABSTRACT FROM AUTHOR]

Background: Since 1910, omentectomy has been an essential component of radical gastrectomy for advanced gastric cancer. However, researchers have recently questioned the benefit of omentectomy in radical gastrectomy. The aim of this meta-analysis was to compare omentectomy and omentum preservation in gastrectomy for advanced gastric cancer in terms of survival outcomes and short-term outcomes. Methods: The PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases were searched. Studies that compared omentum preservation with omentectomy were included. Overall survival (OS) and relapse-free survival (RFS) were analyzed as primary outcomes. Results: Of 3509 records screened, one randomized clinical trial and five propensity-score matched retrospective studies with 1661 patients were selected. Omentum preservation was associated with improved OS (hazard ratio [HR] = 0.757, 95% confidence interval [CI] = 0.603–0.950, P = 0.016, I2 = 0%), but not with improved RFS (HR = 0.821, 95% CI = 0.668–1.009, P = 0.060, I2 = 9%) compared with omentectomy for advanced gastric cancer. Furthermore, less blood loss and shorter operation time were found in the omentum preservation group than in the omentectomy group. Additionally, the rate of peritoneal recurrence, the number of harvested lymph nodes, and the incidences of postoperative complications and ileus were comparable in the two groups. Conclusions: Basing on the current literature, gastrectomy with omentum preservation was associated with improved OS and short-term outcomes compared with omentectomy for advanced gastric cancer. Further randomized trials are required to confirm the survival benefit of omentum-preserving gastrectomy. [ABSTRACT FROM AUTHOR]

Single nanoparticle collisions have become popular for studying the electrochemical activity of single nanoparticles by determining the transient current during stochastic collisions with the electrode surface. However, if only the electrochemical current is measured, it remains challenging to identify and characterize the individual particle that is responsible for a specific current peak in a collision event; this hampers the understanding of the structure-activity relationship. Herein, we report simultaneous optical and electrochemical recording of a single nanoparticle collision; the electrochemical signal corresponds with the activity of a single nanoparticle, and the optical signal reveals the size and location of the same nanoparticle. Consequently, the structure (optical signal)-activity (electrochemical signal) relationship can be elucidated at the single nanoparticle level; this has implications for various applications including batteries, electrocatalysts, and electrochemical sensors. In addition, our previous studies have suggested an optical-to-electrochemical conversion model to independently calculate the electron transfer rate of single nanoparticles from the optical signal. The simultaneous optical and electrochemical recording achieved in the present work enables direct and quantitative validation of the optical-to-electrochemical conversion model. [ABSTRACT FROM AUTHOR]

Based on the compressed sensing (CS) technique, the carrier frequency offset (CFO) is estimated in compressive sampling scenarios. We firstly confirm the compressibility of estimation metric vector (EMV) of conventional maximum likelihood (ML)-based CFO estimation, and thus conduct the compressive sampling at receiver. By exploiting the EMV features, introducing a circle cluster, and proposing a novel coherence-pattern, we then form a feature-aided weight coherence (FAWC) optimization to optimize measurement-matrix. Besides the proposed FAWC optimization, by referencing compressive sampling matching pursuit (CoSaMP) algorithm and exploiting EMV features, a metric-feature based CoSaMP (MFB-CoSaMP) algorithm is proposed to improve the EMV-reconstruction accuracy, and to reduce computational complexity of classic CoSaMP. With reconstructed EMV, we finally develop a CFO estimation method to estimate the coarse CFO and fine CFO. Relative to weighted coherence minimization (WCM) and classic CoSaMP, the elaborate performance evaluations show that the FAWC and MFB-CoSaMP can independently or jointly improve accuracy of the CFO-estimation (including coarse CFO-estimation and fine CFO-estimation), and the improvement is robust to system parameters, e.g., sparsity level, number of measurements, etc. Furthermore, the mean squared error (MSE) of proposed CFO estimation method can almost reach to its Cram $\acute {\texttt {e}}$ r-Rao lower Bound (CRLB) when a relative large number of measurements, a relative high carrier-to-noise ratio (CNR), and a reasonable length of observed signals can be obtained. [ABSTRACT FROM AUTHOR]

This work proposes a qualitative analysis of the particle-induced viscosity reduction phenomenon observed in polymeric composites like polylactic acid (PLA)/partially methylated silica particles, but not in composites like PLA/hydroxyl-terminated silica particles. The analysis is mainly based on considerations of the friction coefficients of spherical particles in the composites. The analysis reveals that sufficiently small particles, relatively weak polymer-particle interfacial interactions, particle rotation, and the existence of interfacial slipping in a polymeric composite are necessary conditions for the occurrence of particle-induced viscosity reduction, while long-distance particle-particle interactions based on polymer-particle interactions, and possibly existing additional interfacial elastic behaviors conversely lead to an increase in viscosity. The ratio of the radius of the particles to the gyration radius of the coils of polymer chains in polymer melts ( R/ R) is found to be not crucial. [ABSTRACT FROM AUTHOR]

The CD2-associated protein (CD2AP) rs9349407 polymorphism was first identified to be significantly associated with Alzheimer's disease (AD) in European ancestry by genome-wide association studies (GWAS). However, the following studies reported no association in Chinese, Japanese, African-American, Canadian, and European populations. We think that these negative results may have been caused by either relatively small sample sizes compared with those used for the previous GWAS in European ancestry or the genetic heterogeneity of the rs9349407 polymorphism in different populations. Here, we reevaluated this association using the relatively large-scale samples from 15 previous studies ( N = 54,936; 23,777 cases and 31,159 controls) by searching the PubMed, AlzGene, and Google Scholar databases. Using an additive genetic model, we did not identify a significant heterogeneity among the 15 studies. Using meta-analysis, we observed a significant association between the rs9349407 polymorphism and AD with P = 8.78E-07, odds ratio (OR) = 1.08, 95 % confidence interval (CI) 1.05-1.12. To our knowledge, this is the first meta-analysis to investigate the association between rs9349407 polymorphism and AD in East Asian, American, Canadian, and European populations. Our analysis further supports previous findings that the CD2AP rs9349407 polymorphism contributes to AD susceptibility. We believe that our findings will be very useful for future genetic studies on AD. [ABSTRACT FROM AUTHOR]

Purpose: To identify the risk factors for apical node metastasis in colorectal cancer (CRC) patients who underwent laparoscopic radical resection with D3 lymphadenectomy. Methods: The subjects were 578 consecutive patients who underwent laparoscopic radical resection with D3 lymphadenectomy for CRC between February, 2003 and December, 2009. The Cox proportional regression model was used to evaluate the association between apical node metastasis and survival and the logistic regression model was used to identify the risk factors for apical node metastasis. Results: Thirty patients (5.2 %) had apical node metastasis, which was an independent risk factor for poor disease-free survival [hazard ratio (HR) = 3.02, P = 0.019]. Multivariate logistic regression analysis revealed that poor differentiation [odds ratio (OR) = 4.58, P < 0.001] and ulcerative/infiltrative morphology (OR = 5.57, P = 0.023) were independent risk factors for apical node metastasis. In the subgroup analysis based on pT3-4 tumors, multivariate logistic regression analysis also suggested that these factors were significantly associated with apical node metastasis. Conclusions: Apical node metastasis is an independent risk factor for poor oncologic outcome. T3-4 stage, poor differentiation, and ulcerative/infiltrative morphology are significantly associated with apical node metastasis. Notably, in this study, T1-2 stage tumors had no apical node metastasis, suggesting that D3 lymphadenectomy may be over-performed without considering the T stage of tumors. [ABSTRACT FROM AUTHOR]

A novel disposable paper-based bipolar electrode (BPE) array is fabricated for multiplexed electrochemiluminescence (ECL) detection of pathogenic DNAs. This proposed BPE array device consists of 15 units, each consisting of six sensing cells and two reporting cells patterned using hydrophobic wax. A hairpin structure DNA assembled on the cathodes of BPEs hybridizes with Pt nanoparticles (NPs) labeled probe DNA in the presence of complementary target DNA. The introduction of Pt NPs catalyzes the reduction of dissolved O at cathodes and induces an enhanced ECL signal from Ru(bpy)/tripropylamine (TPrA) at the anodes of BPEs. The dissolved O lost in reduction reaction could be promptly replenished due to the relatively large contact area of the paper-based cells with air, which ensures the stability of ECL signal. This obtained paper-based BPE array sensor showed excellent performances for the multiplexed analysis of the syphilis (Treponema pallidum) gene, the immunodeficiency virus gene (HIV) and hepatitis B virus gene (HBV). [ABSTRACT FROM AUTHOR]

Background: How to identify whether T1-2 colorectal cancers have lymph nodes metastases pre-op or intra-op is a crucial problem in clinic. The purpose of this study was to evaluate the feasibility of using carbon nanoparticles to track lymph nodes metastases in T1-2 colorectal cancers. Methods: A multi-center study was performed between July 2012 and January 2014. Seventy-three patients with T1-2 colorectal cancer identified by pre-op endoscopic ultrasonography (EUS) were recruited. 1 ml carbon nanoparticles suspension was endoscopically injected into the submucosal layer at four points around the site of the primary tumor 1 day before surgery. Laparoscopic radical resection with lymphadenectomy was performed. Sentinel lymph nodes (SLNs) were defined as nodes that were black-dyed by carbon nanoparticles. Pathology confirmed whether lymph nodes have cancer metastases and the SLNs accuracy. Results: SLNs were easily found under laparoscopy. The mean number of SLNs was 3 (range 1-5). All patients had SLNs lying alongside the mesenteric vessel or main arterial vessel. After pathological analysis, 2 patients (9.52 %) had lymph node metastasis in 21 patients with EUS T1 cancers, and 10 patients (19.23 %) had lymph node metastasis in 52 patients with EUS T2 cancers. In two T1 cases with lymph node metastasis, SLNs were positive with 100 % accuracy. In ten T2 cases with lymph node metastasis, SLNs were positive in nine cases. In pathology, carbon nanoparticles were seen in lymphatic vessels, and lymphoid sinus and macrophages in negative SLNs. When SLNs were positive, carbon nanoparticles were seen around cancer cells in lymph nodes. The overall sensitivity, specificity, accuracy of SLNs in T1-2 colorectal cancers were 91.67, 100, 98.63 %, respectively. Conclusions: We demonstrated the feasibility of using carbon nanoparticles to track lymph nodes metastases in T1-2 colorectal cancers. Carbon nanoparticles black-dyed lymph nodes play a role as SLNs in T1-2 colorectal cancers. [ABSTRACT FROM AUTHOR]

In this work, we propose a robust watermarking algorithm for video copyright protection. The proposed algorithm is characterized by four key features. First, a robust feature obtained by singular value decomposition is selected to embed the watermark. Second, a novel slope-based embedding technique is developed to embed a 1-bit watermark into several successive blocks in the temporal direction, thus enhancing the robustness against global attacks. Third, an embedding location selection method is used to give priority to blocks with small variations that can enhance the visual quality of the watermarked video. Fourth, a temporal synchronization method is introduced to effectively withstand temporal synchronization attacks. The experimental results demonstrate that our scheme has good imperceptibility and is robust against various attacks, such as noise addition, filtering, gamma correction, lossy compression, scaling, frame dropping, frame insertion, and frame averaging. Furthermore, the watermark can be extracted using only some side information rather than the original video, which makes the scheme more practical. [ABSTRACT FROM AUTHOR]

The liver transplant (LT) situation represents an attractive model for studying hepatocellular carcinoma (HCC) metastasis. Based on microarray data, we previously found that miR-126 expression was lower in tumor tissues of patients with post-LT HCC recurrence compared with non-recurrence. In this study, we examined the expression of miR-126 in HCC samples from 68 patients who had undergone LT using quantitative real-time PCR and analyzed its correlation with clinicopathological features and prognosis of patients. Furthermore, we performed experimental analyses to explore the involvement of miR-126 in HCC metastasis. We found that miR-126 levels were lower in tumor tissues of patients with post-LT HCC recurrence in comparison to patients with no-recurrence ( p = 0.009). Lower expression of miR-126 in HCC was associated significantly with tumor recurrence ( p = 0.011) and poor survival ( p = 0.009) of patients. Functional studies indicated that ectopic expression of miR-126 significantly inhibits HCC cells migration, invasion, proliferation and colony formation in vitro, and suppresses experimental lung colonization in vivo. Our study revealed that down-regulation of miR-126 plays an important role in HCC metastasis, and suggest a potential application of miR-126 in prognosis prediction and HCC treatment. [ABSTRACT FROM AUTHOR]

Nanofluidics is a recent appearing research field, introduced in 1995 as an analogue of the field of microfluidics, and has been becoming popular in the past few years. The proximity of the channel dimension, the Debye length, and the size of biomolecules such as DNA and proteins gives the unique features of nanofluidic devices. Of various unique properties of the nanofluidics, mass transport in nanochannel plays determining roles in fundamental reaches and practical applications of nanofluidic device. Thus, much work including numerical and experimental researches has been performed to investigate the mass transport behaviors in nanofluidic devices. This review summarizes the fabrication technologies for nanofluidic devices, the mass transport behaviors in nanochannel, and their applications in bioanalysis. The main focus will be laid on the effects of nanochannel size and surface charge on mass transport including electrokinetic transport of charged analytes, diffusion of electric neutral molecules, ionic current rectification, concentration polarization, nonlinear electrokinetic flow at the micro-nanofluidic interfaces. [ABSTRACT FROM AUTHOR]

A versatile DNA recognition system using cadmium sulfide nanoparticles (CdS NPs) as labels was proposed for ultrasensitive detection of specific sequence DNA based on target recycling. This strategy utilized the magnetic particles (MNPs) for the immobilization of linker DNA and CdS NPs and the subsequent target DNA hybridization. Using the unique characteristic of nicking endonuclease for cutting one specific strand of double strand DNA (ds DNA), the linker DNA could be transected and the target DNA could be liberated for re-hybridization and hence the amount of released CdS NPs was enhanced. Due to the advantage of the MNPs and signal amplification from the target recycling, the analyte DNA could be detected by the square-wave stripping voltammetry (SWV) in a wide linear range from 0.4 fM to 100 fM with the detection limit down to 0.08 fM. The proposed DNA detection strategy possesses high sensitivity, satisfactory reproducibility and excellent stability, which might have potential in other DNA biological assays. [ABSTRACT FROM AUTHOR]

A core-shell Rhodamine B-doped SiO2 nanoparticle was synthesized and its fluorescent intensity was found to be 1000 times higher than that of individual Rhodamine B molecule. The doped nanoparticles were further conjugated with streptavidin and the resulting nanoparticles were used in the detection of reverse-phase protein microarrays, in which human IgG of various concentrations was first immobilized on aldehyde-modified glass slides and then biotinlyated goat anti human IgG as well as the labeled nanoparticles were sequentially conjugated. The calibration curve is linear over the range from 800 fg to 500 pg and the limit of detection is 100 fg, which is 8 times lower than that of streptavidin-labeled Cy3 fluorescent dyes. The dye-doped SiO2 nanoparticles show potentials for the protein array detection. [ABSTRACT FROM AUTHOR]

Photoelectrochemical sensor is a new kind of developing analytical device based on the photoelectrochemical properties of materials. Because of its remarkable sensitivity, inherent miniaturization, portability and easy integration, photoelectrochemical analysis is becoming a promising analytical technique. This review focuses on the basic principles, classification, characteristics, and research progress of photoelectrochemical sensors with 94 references. The prospect of the development of photoelectrochemical sensors is also evaluated and discussed. [ABSTRACT FROM AUTHOR]

In this paper, three-dimensional ordered macroporous platinum catalysts with high real surface area were synthesized using the inverted colloidal crystals template technique and have been employed for the electrooxidation of methanol. The morphology and electrocatalytic behavior of the porous Pt electrodes were investigated with atomic force microscopy and electrochemical techniques. For the same amount of Pt deposited, the real surface areas of the electrodes are 9.16 and 8.00 cm² for the porous electrodes with pore size of 320 and 500 nm respectively, which are more than 5 times larger than the directly deposited Pt electrode (1.4 cm²). The pore size effect on the methanol electrooxidation was investigated by testing low concentration solution of methanol and porous materials with different pore sizes. The synthesized macroporous Pt electrode shows high stability toward the electrooxidation of methanol and is promising for the direct methanol fuel cell. [ABSTRACT FROM AUTHOR]

The o-aminophenol (OAP)-H2O2-horseradish peroxidase (HRP) voltammetric enzyme-linked immunoassay new system has extremely high sensitivity. HRP can be measured with a detection limit of 6.0×1010 g/L and a linear range of 1.0×10-9-4.0×10-6 g/L. The pure product of H2O2 oxidizing OAP catalyzed by HRP was prepared with chemical method. The enzyme-catalyzed reaction has been investigated with electroanalytical chemistry, UV/Vis spectrum, IR spectrum,13C NMR,1H NMR, mass spectrum, elemental analysis, etc. Under the selected enzyme-catalyzed reaction conditions, the oxidation product of OAP with H2O2 catalyzed by HRP is 2-aminophenoxazine-3-one. The processes of the enzyme-catalyzed reaction and the electroreduction of the product of the enzymecatalyzed reaction have been described. [ABSTRACT FROM AUTHOR]

Conventional atomic force microscopy (AFM) tips have remained largely unchanged in nanomachining processes, constituent materials, and microstructural constructions for decades, which limits the measurement performance based on force-sensing feedbacks. In order to save the scanning images from distortions due to excessive mechanical interactions in the intermittent shear-mode contact between scanning tips and sample, we propose the application of controlled microstructural architectured material to construct AFM tips by exploiting material-related energy-absorbing behavior in response to the tip–sample impact, leading to visual promotions of imaging quality. Evidenced by numerical analysis of compressive responses and practical scanning tests on various samples, the essential scanning functionality and the unique contribution of the cellular buffer layer to imaging optimization are strongly proved. This approach opens new avenues towards the specific applications of cellular solids in the energy-absorption field and sheds light on novel AFM studies based on 3D-printed tips possessing exotic properties. The authors investigate 3D-printed tips, based on controlled microstructural architectured materials, as probes for shear-mode atomic force microscopy. They demonstrate that the tailored stiffness and energy-absorbing behaviour of the material are beneficial for improving image quality. [ABSTRACT FROM AUTHOR]

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Three dinuclear CuII perchlorate complexes of macrocyclic ligands derived from the condensation of sodium 4-X-2,6-diformylphenolate (X=Me, Cl or But) with 1,5-diamino-3-(8-methylquinolyl)azapentane were prepared by in situ transmetallation with Cu(ClO4)2 and characterized by physicochemical, spectroscopic and electrochemical methods. [ABSTRACT FROM AUTHOR]

Maintaining innate immune homeostasis is important for individual health. Npl4 zinc finger (NZF) domain-mediated ubiquitin chain sensing is reported to function in the nuclear factor-kappa B (NF-κB) signal pathway, but the regulatory mechanism remains elusive. Here we show that cyclophilin J (CYPJ), a member of the peptidylprolyl isomerase family, is induced by inflammation. CYPJ interacts with the NZF domain of transform growth factor-β activated kinase 1 binding protein 2 and 3 as well as components of the linear ubiquitin chain assembly complex to block the binding of ubiquitin-chain and negatively regulates NF-κB signaling. Mice with Cypj deficiency are susceptible to lipopolysaccharide and heat-killed Listeria monocytogenes-induced sepsis and dextran sulfate sodium-induced colitis. These findings identify CYPJ as a negative feedback regulator of the NF-κB signaling pathway, and provide insights for understanding the homeostasis of innate immunity. Nuclear factor-kappa B (NF-κB) signaling is regulated by ubiquitin to maintain immune homeostasis. Here the authors show that a peptidylprolyl isomerase, CYPJ, blocks TAB2/3 or LUBAC ubiquitin chain sensing and suppress NF-κB activation, with CYPJ-deficiency leading to susceptibility to inflammatory stimuli. [ABSTRACT FROM AUTHOR]