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Introduction: The incidence of adenocarcinoma of esophageal-gastric junction (AEJ) has been increasing in recent years. Esophagogastrostomy after proximal gastrectomy (PG-EG) is the most commonly used surgical method for this disease which causes a constant spasm of the pyloric sphincter by cutting the vagus nerve around the esophagus, so H-M pyloroplasty (Heineke-Mikulicz pyloroplasty) is often operated after PG-EG to prevent delayed gastric emptying. However, H-M pyloroplasty destroys anti-reflux structure of pylorus and leads to serious bile reflux. The present study was designed to compare pyloromyotomy and H-M pyloroplasty in proximal subtotal gastrectomy through clinical studies and animal experiments.Methods: We retrospectively evaluated the outcomes of 73 AEJ patients (39 underwent PG-EG with an H-M pyloroplasty and 34 underwent PG-EG with a pyloromyotomy) between January 2016 and August 2020, and perioperative variables were compared. In the animal experiment, 48 rats were randomly divided into four groups (n = 12): vagotomy group (V group), H-M pyloroplasty group (HM group), pyloromyotomy group (PM group), and control group (O group). Gastric emptying and bile reflux were evaluated in each group.Results: In the retrospective clinic study, pyloromyotomy and H-M pyloroplasty could all prevent delayed gastric emptying effectively, and the incidence of bile reflux found by electronic gastroscopy in the PM group was significantly lower than that in the HM group (HM, 14/39; PM, 4/34; P = 0.028). In the animal experiment, there was no significant between-group difference of gastric emptying rate (%) in the HM group and PM group (HM, 70.6 ± 16; PM, 72.3 ± 12; P = 0.68) while the gastric emptying rate (%) was significantly lower in the V group than in the HM, PM, and control group (P values were 0.037, 0.021, and 0.001 respectively). The gastric mucosa bile acid concentration was significantly higher in the HM group than other group (P values were all less than 0.001).Conclusions: The pyloromyotomy could prevent delayed gastric emptying effectively after PG-EG for types II and III AEJ and reduce bile reflux compared to Heineke-Mikulicz pyloroplasty. [ABSTRACT FROM AUTHOR]

Colon cancer is the third most commonly diagnosed and deadly cancer worldwide. Efforts have been made to characterize its pathological mechanisms and to explore new therapeutic targets of this disease. Aberrant expression of long noncoding RNAs (lncRNAs) has been associated with the pathogenesis of colon cancer. In the current study, we aimed to define the biological mechanism of the lncRNA BC200 in colon cancer. Here, we found that expression of BC200 was up-regulated in colon cancer tissues as compared with adjacent non-cancerous tissues. The BC200 level was positively correlated with advanced TNM stage. The Kaplan–Meier method indicated that the cumulative survival rate was significantly lower in patients with high BC200 expression than in those with low BC200 expression. Interestingly, we found that knockdown of BC200 inhibited proliferation of HCT-116 and HT29 colon cancer cell lines and reduce the expression of cell proliferation markers, such as Ki-67 and PCNA. In addition, silencing of BC200 could induce obvious G0/G1 arrest and cause apoptosis in HCT-116 and HT29 cells and reduced the expression of cyclin D1, cyclin E, and c-Myc through inhibiting the expression of β-catenin. Importantly, we found that knockdown of BC200 reduced invasion of HCT-116 and HT29 cells and epithelial-mesenchymal transition (EMT) by reducing the expression of MMP-2 and MMP-9. Mechanistically, silencing of BC200 significantly reduced the phosphorylation of STAT3. Overall, the findings presented here suggest that lncRNA BC200 may serve as a novel oncogene and a new therapeutic target for colon cancer. [ABSTRACT FROM AUTHOR]

Dopamine (DA), an important neurotransmitter, has been reported to play a negative role in tumor progression. DA acts its role via dopamine receptors (DRs), which can be divided into five receptor subtypes (D1R-D5R). Among these receptor subtypes, D2R has been found to inhibit IGF-I-induced gastric cancer cell growth. However, the functions of D2R in gastric cancer cell invasion remain elusive. Here, we found that D2R expression was decreased in gastric cancer cells. DA treatment dose-dependently inhibited EGF-mediated gastric cancer cell invasion and migration via D2R. Furthermore, D2R decreased EGF-mediated MMP-13 production, and attenuated EGFR and AKT activation. Together with the results that EGF promoted gastric cancer cell invasion and migration via EGFR/AKT pathway, these data indicate that DA treatment, acting via D2R, suppresses gastric cancer cell invasion and migration via inhibition of EGFR/AKT/MMP-13 pathway. Thus, our findings suggest that use of D2R agonist may have a potential therapeutic effect on gastric cancer. [ABSTRACT FROM AUTHOR]

The iron (Fe) cobalt (Co) tungsten (W) alloys exhibit unique combinations of mechanical and soft magnetic properties, good corrosion and wear resistance, and biocompatibility, which makes them desirable candidate for numerous practical applications. A nano-porous alumina template with electrodeposited FeCoW alloy nanowires (NWs) is a polycrystalline material with the grain size was about ~1 − 3 nm. Here, we first time report the composition dependent structural, and magnetic properties of FeCoW NWs embedded in ~25 nm anodic alumina (AAO) template by electrodeposition. By keeping the W concentration same, and decreasing the concentration of Co2+ and Fe2+ ions in the solution, 2–3% to 8–9% W content was increased. The EDX and XPS analysis confirms the co-deposition of W ions along with Fe and Co ions. The magnetization curves showed that 2–3% At. % of W in CoFe NWs significantly increases the saturation magnetization of NWs. Therefore, FeCoW alloy with low W content could be targeted for the design of recording components and shape memory devices in future. Deposition potential also has a notable effect on the final composition, structure and magnetic properties of NWs. • Highly-ordered FeCoW NWs were prepared by DC electrodeposition with concentrations of W in the range of 0 to 8 at%. • CV was performed on Ag films to analyse the electrochemical reduction behaviour of Fe,Co and W ions. • The structural and magnetic characterization shows that the W addition transforms micromagnetic properties of NWs. • FeCoW NWs with low W content could be applied for the design of recording components and shape memory devices in future. [ABSTRACT FROM AUTHOR]

Hydrogen segregation behaviors at BCC-Fe Σ3 (111) grain boundary (GB) as well as the effects of alloying solutes were studied by the first-principles method. The segregation energy of alloying solutes at different periods presents a concave-down parabolic-like relationship with the atomic number, and the 4 d transition alloying solutes show a higher averaged segregation tendency. At the favorable trapping site, hydrogen segregation energy decreased by increasing the number of hydrogen atoms up to 0.85/Å2 in the plane vertical to the GB. Mo, Tc, Ru, Ta, W, Re, Os, and Ir strengthen GB and inhibit hydrogen segregation. Significantly, the interaction between alloying solutes and hydrogen segregation was elucidated by emphasizing the separation of the chemical and the mechanical contributions, and appropriate descriptors on hydrogen segregation energy influenced by alloying solutes were screened. This work offers theoretical backing to comprehend hydrogen segregation behaviors and the effects of alloying solutes to design advanced high-strength steels resistant to hydrogen embrittlement. • Hydrogen segregation behaviors at pure BCC Σ3 (111) grain boundary were studied. • Alloy solute segregation behaviors at pure BCC Σ3 (111) grain boundary were studied. • Interaction between alloying solutes and hydrogen at grain boundary was elucidated. • Descriptors on hydrogen segregation energy at grain boundary were screened. • Relationship between hydrogen segregation at grain boundary and HE was discussed. [ABSTRACT FROM AUTHOR]

In order to enhance the integration of the SOFC stack module and facilitate the assembly of the external manifold stack, a bottom-access structure stack was developed. Computational fluid dynamics (CFD) techniques were employed to investigate the gas distribution of the stack. Multiple parameters, such as geometrical parameters, manifold structures, and buffer chambers were optimized to improve flow distribution uniformity. The results indicated that the introduction of guide plates and distributors in the manifold helped to prevent vortex generation, which led to an increase in the mass flow rate of cells near the inlet. The uniformity of flow distribution can be greatly improved by increasing the buffer chamber height, but when the buffer chamber height is excessive, it has the opposite effect. The depth of the manifold only has a limited impact on the flow distribution. Ultimately, the optimal structure was found to be the manifold with guide plates and buffer chambers, which reduced flow non-uniformity from 8.4% to 1.4%. These findings provide reliable guidance for the improvement of flow distribution in the bottom-access stack. [Display omitted] • Flow uniformity of the stack was optimized by numerical simulation. • Guide plates and distributors in manifolds can prevent vortex generation. • The buffer chamber height affects mass flow rate of cells near inlet. • The depth of the manifold has a limited impact on the flow distribution. [ABSTRACT FROM AUTHOR]

The interplay of hydrogen, vacancy and grain boundary plays an important role in hydrogen induced premature fracture in the metallic materials. In this work, two models with the representative high angle grain boundaries with the low and high grain boundary energy have been built according to the coincidence site lattice theory. The effects of hydrogen and hydrogen-vacancy combination on the deformation behaviors of the two models were investigated by means of molecular dynamics simulation with the straining direction vertical to the grain boundary. It is found that in both cases hydrogen tends to segregate and maintain a high local stress state around the grain boundary, and promote the premature fracture compared with the hydrogen-free model. Vacancy enhanced the effects of hydrogen in the model with grain boundary of the lower energy. However, vacancy promoted the dislocation evolution behavior in the model with grain boundary of the higher energy. The simulation results were further explained by considering the effects of hydrogen on the generalized stacking fault energy and the work of separation of the grain boundary. • Both hydrogen and vacancy tend to reduce the work of separation of the Σ3 grain boundaries. • Hydrogen keeps the Σ3 symmetric tilt grain boundaries in a high stress state. • Hydrogen and vacancy form the vacancy-H clusters at the Σ3 (112) grain boundary. • Hydrogen enhances the brittle fracture of the Σ3 (111) grain boundary. [ABSTRACT FROM AUTHOR]

The effect of a 12 Tesla magnetic field on the microstructure and carbon partitioning in a low temperature bainitic steel isothermally transformed at 300 °C was investigated. The application of the high magnetic field significantly accelerated the formation of bainitic ferrite. The acceleration can be attributed to additional magnetic Gibbs free energy (ΔG M). Compared with a sample transformed without the magnetic field, the bainitic ferrite laths were refined and the distribution became more uniform; the alignment and orientation of the laths was more regular in a given austenite grain. Meanwhile, a high magnetic field promotes carbon partitioning from bainitic ferrite to retained austenite (RA) and increases the carbon accommodation of the retained austenite. • Low-temperature bainite transformation was accelerated by high magnetic field. • Finer and more uniform bainitic ferrite laths were obtained by high magnetic field. • Carbon partitioning was promoted by application of high magnetic field. • The carbon accommodation of retained austenite was improved by high magnetic field. [ABSTRACT FROM AUTHOR]

Cisplatin is one of the most effective chemotherapeutic agents for the treatment of lung cancer. However, the acquired resistance occurred in cancer cells limits the clinical application of cisplatin. MCL-1, which is an important member in the pro-survival Bcl-2 family, plays a critical role in multidrug resistance (MDR). The aim of the present study is to investigate the value of Pan-Bcl-2 inhibitor as sensitizer for the chemotherapy of cisplatin-resistant non-small cell lung cancer (NSCLC) cells. We found the obatoclax but not the ABT-737 significantly decreased the IC50 (half maximal inhibitory concentration) of cisplatin in cisplatin-resistant NSCLC cells. Furthermore, we demonstrated that the mechanism of obatoclax-promoted cell death induced by cisplatin was dependent on the inhibition of MCL-1, which couldn't be inhibited by ABT-737 but is the target of obatoclax. Moreover, inhibition of MCL-1 recovered the function of NOXA and BAK in cisplatin-resistant NSCLC cells, leading to the promotion of mitochondrial apoptosis induced by cisplatin. Interestingly, our date indicated the obatoclax also reversed the cross-resistance in cisplatin-resistant NSCLC cells. Therefore, we demonstrated that the targeted therapy with MCL-1 inhibitors, such as obatoclax, may represent a novel strategy for cancer therapy. [ABSTRACT FROM AUTHOR]

Thermal stress and contact are two pivotal factors influencing the operational lifespan and performance of solid oxide fuel cell (SOFC) stacks. In practical kW-MW SOFC systems, stack boxes are typically constructed using kW-class stack blocks comprising dozens of cells. Temperature distribution affects the thermal stress distribution, thus affecting the contact of the stack. In this work, the thermal stress distribution and contact of a 2.5 kW external-manifold stack composed of 60 repeat units are investigated by using finite element analysis (FEA). To get a more accurate and realistic results, temperature data of a stack measured in an ongoing SOFC system is incorporated into the computational model. The influences of the clamp loads from manifolds, the structure of current collectors, the number of spacer plates, and the thickness of interconnects on the thermal stress distribution and contact of the stack are investigated. In the basic stack, the tensile stress induced by the temperature gradient appears to be the primary cause of the high thermal stress in the air inlet region of top cells. Due to the high-temperature strength of the seal material and endplates, the contact is inferior in cells near endplates. Increasing the clamp loads of manifolds within specified limits leads to a reduction in both the magnitude and area of high thermal stress, concurrently enhancing the stack contact. Strengthening the current collector structure induces more high-stress regions and simultaneously increases the stack contact. The introduction of overmuch spacer plates results in more high stress regions and a deterioration in stack contact. Moreover, increasing the thickness of interconnects introduces more high stress regions, negatively impacting stack contact. • 3D FEA model of a 2.5 kW SOFC stack composed of 60 cells was constructed. • Temperature data of an ongoing SOFC system was incorporated into the model. • The stack's thermal stress and contact were simultaneously investigated. • The impacts of stack components on thermal stress and contact were studied. • Causes of high thermal stress and poor contact were revealed. [ABSTRACT FROM AUTHOR]