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Background: The current study was undertaken to investigate the time course of gastric ischemia-reperfusion (GI-R)-induced gastric mucosal injury and repair and whether extracellular signal-regulated kinase 1/2 (ERK1/2) were involved in GI-R-induced gastric mucosal injury and repair.Methods: Immunohistochemistry and Western blot analyses were used.Results: Gastric mucosal injury induced by ischemia alone was mild. However, the injury worsened after reperfusion, reaching a maximum at 1 h, and was accompanied by increased apoptotic cells and decreased proliferative cells. Then, the gastric mucosal cells began to repair the injury by enhanced proliferation, which peaked at 24 h after reperfusion, and by 72 h the damaged gastric mucosa was mostly repaired. The ERK1/2 (nonactivated ERK1/2) protein expression level and distribution profile showed no significant changes during the entire reperfusion phase, but the p-ERK1/2 (activated ERK1/2) level changed dramatically. The p-ERK1/2 protein level was decreased at 0.5 h after reperfusion began, and then gradually increased, peaking after 3 h of reperfusion; these changes in p-ERK1/2 occurred simultaneously in the cytoplasm and nucleus. On the other hand, inhibition of the activation of ERK1/2, induced by PD98059, a specific ERK1/2 upstream inhibitor, aggravated the gastric mucosal injury, and apoptosis was increased and proliferation was reduced in the gastric mucosal cells after the same duration of reperfusion.Conclusions: Serious gastric mucosal damage involving apoptotic cells occurred rapidly at an early stage of reperfusion and was closely related to the suppression of ERK1/2 activation. The activated ERK1/2 signaling transduction pathway played an important role. Activated ERK1/2 participated in the regulation of gastric mucosal injury and repair induced by GI-R, and might be mediated by the inhibition of apoptosis and the promotion of proliferation in gastric mucosal cells. [ABSTRACT FROM AUTHOR]

A low-cost porous bimetallic hybrid electrocatalyst (Ni/Mo 6 Ni 6 C@C nanoparticle) has been synthesized via a soft-template using Polyethylenimine (PEI), Polyoxometalate (POM) and metal ion as precursors. • The bimetallic catalysts Ni/Mo 6 Ni 6 C@C were synthesized by a soft-template method. • The intermolecular forces in precursors are the basis of forming Ni/Mo 6 Ni 6 C@C. • Ni/Mo 6 Ni 6 C@C exhibited excellent catalytic activity and durability for HER. • DFT calculations pinpoint the origin of the excellent performance of Ni/Mo 6 Ni 6 C@C. Hydrogen generated by water splitting devices is a promising way to solve energy issues, which is limited by Pt-based precious catalysts. Developing efficient Pt-free electrocatalyst for hydrogen evolution reaction (HER) is highly essential for the practical applications. Herein, we report a soft-template method to fabricate an efficient porous bimetallic hybrid material, dubbed Ni/Mo 6 Ni 6 C@C. Benefiting from the bimetallic feature and porous structure, Ni/Mo 6 Ni 6 C@C exhibits low overpotentials of 101 and 122 mV at 10 mA cm−2 with robust stability in alkaline and acidic media, respectively. Theoretical calculations demonstrate that the C sites of the Mo 6 Ni 6 C possess the most excellent electrocatalytic activity due to its Gibbs free energy of hydrogen adsorption closer to 0 eV. Moreover, the superior stability, metallic character and mechanical property are characterized by first-principles calculations, which are advantageous for the Mo 6 Ni 6 C to be the HER catalyst. This study supplies a concise strategy to prepare the highly efficient bimetallic electrocatalyst for HER. [ABSTRACT FROM AUTHOR]

• We found that glutamate stimulation of PVN reduced visceral sensitivity in the CVH rats. • We clarified that chemical ablation of PVN or NTS reversed the effect of PVN on CVH. • The microinjection of AVP-V 1 receptor antagonist DPVDAV into NTS promoted CVH. • The vagal nerve is participated in the CVH process. • We first reported that PVN and NTS are involved in the regulation of CVH. Chronic visceral hypersensitivity (CVH) is a major pathophysiological feature of patients experiencing in irritable bowel syndrome (IBS) and other disorders with visceral pain. However, little is known about its regulation of the central nucleus. In this research, we investigated the protective effect of microinjection of glutamate into hypothalamus paraventricular nucleus (PVN) on CVH and its possible regulatory mechanism in rats. Visceral sensitivity was assessed by pain threshold, abdominal withdrawal reflex (AWR) score, and the abdominal external oblique muscle electromyography (EMG) amplitude. Pathological changes in colorectal mucosa were assessed using immunohistochemical, biochemical analysis and Western blot. Results showed that microinjection of different doses of glutamate into PVN reduced the visceral sensitivity in a dose-dependent manner. This effect can be reversed after chemical ablation of PVN or nucleus tractus solitarius (NTS) or pretreatment with the arginine vasopressin (AVP)-V 1 receptor antagonist ([Deamino-pen1,val4,D-Arg8]-vasopressin) DPVDAV into NTS. The vagus discharge frequency was significantly reduced after the glutamate microinjection into PVN. Additionally, oxidation, proliferation and apoptosis in colorectal mucosa were related to the CVH regulations. These findings suggested that PVN and NTS are involved in the regulatory process of CVH and exert the protective effect on CVH, providing new ideas and therapeutic targets for CVH research. [ABSTRACT FROM AUTHOR]

Rice is generally consumed in the form of milled rice. The yield of total milled rice and head mill rice is affected by both the paddy rice yield and milling efficiency. In this study, three recombinant inbred line (RIL) populations and one F4:5 population derived from a residual heterozygous (RH) plant were used to determine quantitative trait loci (QTLs) affecting milling yield of rice. Seven traits were analyzed, including recovery of brown rice (BR), milled rice (MR) and head rice (HR); grain yield (GY); and the yield of brown rice (BRY), milled rice (MRY) and head rice (HRY). A total of 77 QTLs distributed on 35 regions was detected in the three RIL populations. Four regions, where qBR5, qBR7, qBR10, and qBR12 were located, were validated in the RH-derived F4:5 population. In the three RIL populations, all the 11 QTLs for GY detected were accompanied with QTLs for two or all the three milling yield traits. Not only the allele direction for milling yield traits was unchanged, but also the effects were consistent with GY. In the RH-derived F4:5 population, regions controlling GY also affected all three milling yield traits. Results indicated that variations of BRY and MRY were mainly ascribed to GY, but HRY was determined by both GY and HR. Results also showed that the regions covering GW5–Chalk5 and Wx loci had major effects on milling quality and milling yield of rice. These two regions, which have been known to affect multiple traits determining grain quality and yield of rice, provide good candidates for milled yield improvement. [ABSTRACT FROM AUTHOR]

Random telegraph noise (RTN) signals in Ge x Se 1-x ovonic threshold switching (OTS) selector have been analysed in this work, both before and after the first-fire (FF) operation and at on- and off-states. It is observed that RTN appears after the FF, and its absolute amplitude at the off-state is small and negligible in comparison with the RTN signals in RRAM devices. At the on-state, large RTN signals are observed, which can either partially or fully block the conduction path, supporting that a conductive filament is formed or activated by FF and then modulated during switching. Statistical analysis reveals that the relative RTN amplitude at on-state in Ge x Se 1-x OTS selector is smaller than or equivalent to those in RRAM devices. Unlabelled Image • Random telegraph noise signals are analysed in Ge x Se 1-x ovonic threshold switching (OTS) selector. • RTN appears after first-fire, with small absolute amplitude at the off-state, and is negligible in 1S1R operation. • On-state RTN is larger and can either partially or fully block the conduction path • Relative RTN amplitude at on-state in OTS is smaller than or equivalent to that in RRAMs [ABSTRACT FROM AUTHOR]