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[Display omitted] • The spherical nano-silica support was prepared by the sol–gel method. • The uniform and fine spherical nano-silica catalytic performance was excellent. • The characteristics of the support varied depending on the ethanol molar ratio. • The feed gas component suitable for H 2 /CO ratio of 2 was optimized. • High stability of the catalyst produced syngas well for 100 h. Combined steam and dry reforming of methane (CSDRM) is expected to be promising when considered as a new alternative feedstock for F-T synthesis because it can produce high-quality syngas without carbon deposition. In this study, the support particle sizes were varied independently to assess their influence on the performance of the metallic Ni. The catalytic activity is most influenced by nickel particle size and distribution, and it has also been investigated for its significant role in the metal-support interaction. To perform CSDRM, the Ni-based catalyst was prepared by impregnation method on a spherical nano-silica support prepared by sol–gel method. The size of the spherical silica nanoparticles (40–300 nm) was controlled by varying the ethanol molar concentration; the spherical particles showed high performance on a uniform and evenly drawn support. In the 44 nm spherical silica catalyst, it was confirmed that the maximum dispersion increased to 21 % and the reducibility increased to 36 %. For stable synthesis gas production, various feed gas ratios (0.7:1.3:1.7) were established and the respective feed gas components (CH 4 , CO 2 and steam) and reactions were investigated. Also, with the increase in the concentration of steam in the feed gas ratio, there was a significant increase in CO production. This trend was attributed to competing reactions occurring due to the side reactions (WGS↔RWGS; CO+H 2 O↔CO 2 + H 2) and was investigated with equilibrium constant values using thermodynamic equilibrium plot data. From the experimental results obtained, the catalyst showed high performance on a stable support and produced a stable H 2 /CO ratio of 2 for 100 h, without side reactions, at the feed gas ratio (CH 4 :CO 2 :H 2 O = 1:0.6:0.85). [ABSTRACT FROM AUTHOR]

Exploring host cell specificity, pathogenicity, and molecular mechanisms of the vacuolating cytotoxin A (VacA), secreted by Helicobacter pylori (Hp) is crucial for developing novel treatment strategies. VacA affects subcellular events, particularly mitochondria, at a cell-type-specific level. However, the lack of reliable models that mimic VacA-induced subcellular damages and enable novel drug screening linked to the human stomach clinically limits our understanding of the mitochondrial networks in vivo. Here, human antrum gastric organoids (hAGOs) and tissue samples from Hp -infected patients were used to show the toxic effects of VacA-induced mitochondrial damage mainly in mucus-producing gastric pit cells by employing transcriptional, translational, and functional analyses. In VacA-intoxicated or Hp -infected hAGOs, robust mitochondrial fragmentation in gastric pit cells reduced ATP production during respiration, and loss of mucosal barrier integrity was first demonstrated experimentally. Using hAGOs, clinically relevant small molecules were screened for efficacy, and MLN8054, an Aurora kinase A inhibitor, reversed VacA-induced mitochondrial damage and loss of gastric epithelium integrity. MLN8054 was effective in VacA-treated and Hp -infected hAGOs and mice, highlighting hAGOs as a promising drug-screening model. These findings suggest that mitochondrial quality control may serve as a promising therapeutic target for Hp VacA-mediated toxicity and disease progression. [Display omitted] [ABSTRACT FROM AUTHOR]

Catalytic amine regeneration can decrease the energy required for regeneration; therefore, high economic and energy efficiency can be expected for CO 2 capture. These factors necessitate the development of an inexpensive and easily synthesizable catalyst that can exhibit a high desorption efficiency. When selecting a catalyst, its physicochemical properties must be considered, because they markedly affect the chemical reaction between CO 2 –amine–catalyst. In this study, mesoporous silica SBA-15, particularly, rod-type SBA-15, wrinkled SBA-15 (modified from rod-type SBA-15), and NiO-impregnated rod-type and wrinkled SBA-15 catalysts were investigated in terms of the CO 2 desorption rate and heat duty in a CO 2 –rich 5 M monoethanolamine (MEA) solution at 86 ℃. The physicochemical properties of the catalysts were compared to investigate their effect on the CO 2 desorption efficiency. The performance of wrinkled SBA-15 impregnated with 10 wt% NiO in a CO 2 –rich MEA solution was optimal, exhibiting a 12 % higher CO 2 desorption rate and 19.9 % lower heat duty than the MEA solution without a catalyst. Furthermore, the stability and reproducibility of the catalysts were confirmed through repeated experiments under identical conditions. Based on the experimental results and analysis, a plausible desorption mechanism for CO 2 –MEA–catalyst was proposed. It is expected that the regeneration heat duty during the CO 2 regeneration can be effectively reduced by a catalyst, eventually applied to the CO 2 capture. [Display omitted] • Wrinkled spherical SBA-15 was derived from the conventional rod-type SBA-15. • Wrinkled spherical SBA-15 with NiO exhibited high CO 2 desorption performance. • Modification of SBA-15 promotes mass transfer during the reaction. • Impregnation of NiO enhances total acid sites in the catalysts. • Catalytic amine regeneration depends on the catalysts' physicochemical properties. [ABSTRACT FROM AUTHOR]

Clostridium acetobutylicum is an attractive industrial microorganism for biochemical production, but there have been few attempts for bio-hydrogen production based on metabolic engineering. In this study, metabolically engineered C. acetobutylicum carrying glucose-6-phosphate dehydrogenase (zwf) and FeFe hydrogenase (hydA) were constructed as recombinant strains CA-zwf(pIMP-zwf) and CA-hydA(pMTL-hydA), respectively, to improve hydrogen productivity. The results showed that the engineered strains produced 1.15 and 1.39-fold higher hydrogen yield, respectively, than the wild type. Furthermore, when pH and glucose concentration were optimized for the CA-hydA strain, enhanced hydrogen productivity of 25.8% was achieved in 7 L jar scale fermentation. This result provides an insight into the future direction for metabolic engineering of C. acetobutylicum for improved hydrogen production. [Display omitted] • Overexpression of FeFe hydrogenase (hydA) improves the hydrogen production in C. acetobutylicum. • Overexpression of glucose-6-phosphate dehydrogenase (zwf) improves the hydrogen production in C. acetobutylicum. • Lactate accumulation was significantly decreased by overexpression of hydA in C. acetobutylicum. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSC) with low levels of reactive oxygen species (ROS) are resistant to conventional chemotherapy or radiation therapy. Peroxiredoxin 2 (Prx2) is a redox regulatory protein that plays a key role in maintaining ROS homeostasis in the tumor microenvironment. However, despite the role of Prx2 in ROS-mediated signal transduction, the association of Prx2 with stemness via ROS in CSC has not been thoroughly investigated. In this study, we investigated the link between Prx2 and CSC stemness through regulation of ROS levels in hepatocellular carcinoma (HCC) cells. ROS induced CSC stemness reduction and downregulated stem cell markers in Huh7 and SK-HEP1 cells. Prx2 knockdown decreased CSC sphere formation and expression of stem cell makers with increasing intracellular ROS levels. This effect was reversed by the ROS scavengers NAC and GSH in Prx2 knockdown cells. Conversely, we found that Prx2 overexpression promotes CSC stemness and the peroxidase activity of Prx2 is essential for CSC stemness using peroxidase inactive mutant, Prx2C51/172S. More importantly, the hyperoxidation-resistant mutant (Prx2ΔYF), which has a constant ROS scavenging activity even at high concentrations of ROS, increased the CSC stemness and expression of stem cell markers more than Prx2WT under oxidative stress. Taken together, our findings demonstrate that Prx2 links ROS homeostasis to CSC stemness; Prx2 is a mediator between ROS homeostasis and CSC stemness. fx1 • ROS inhibits CSC stemness and the expression of stem cell markers in HCC cells. • Prx2 knockdown decreases CSC stemness by regulating ROS levels. • Prx2 overexpression increases CSC stemness and its peroxidase activity is essential for CSC stemness. • Prx2 resistant to hyperoxidation (Prx2ΔYF) promotes CSC stemness under oxidative stress. [ABSTRACT FROM AUTHOR]

Problem It has been reported that some adolescents and young women who started taking human papillomavirus (HPV) vaccination are not completing all three doses. The aim of this study was to systematically review intervention studies on HPV vaccination completion. Eligibility Criteria Intervention studies with a comparison group that assessed HPV vaccination completion rate as the primary outcome variable in adolescents and adults younger than 26 years of age, and published in English from 2006 to 2016, were eligible for review. Sample Five studies from a literature search of CINAHL, EMBASE, PsycARTICLES, PubMed, SCOPUS, and Web of Science databases were included in this review. Results The overall quality of the reviewed studies was moderate, and the studies have mainly been conducted in a high-income country. Intervention strategies were DVD-based education on HPV and reminders that were delivered via either electronic or non-electronic methods. Some studies used fixed type of electronic reminders. Others chose preference-based electronic reminders, allowing participants to select one or two delivery options from e-mail, text message, automated telephone message, or Facebook message. Non-electronic reminders were letters sent by standard mail. Conclusions The rates of HPV vaccination completeness increased with the interventions. However, the completeness rate of HPV vaccination remained unsatisfactory and lower than its initiation rate. Implications Educational and reminder interventions for HPV vaccination could contribute to HPV vaccination completion. However, this review highlights the need for more high-quality studies to identify the best way to promote vaccination completion. [ABSTRACT FROM AUTHOR]

Two fluorescent 2′-deoxyuridines, U AF and U DAF , labeled with 2-aminofluorene and 2-dimethylaminofluorene units, respectively, and having values of p K a of 4.27 and 4.66, respectively, display ‘turn-on’ emission responses in acidic solutions. They can also penetrate into HeLa cell membranes, where they exhibit their strong fluorescence under acidic conditions. [ABSTRACT FROM AUTHOR]

This study applies two isostructural zeolitic imidazolate frameworks (ZIF-8 and ZIF-67) to rapidly adsorb and remove sulfur mustard (HD), a chemical warfare agent. Because HD is extremely toxic, some of the studies were conducted using an HD simulant, 2-chloroethyl ethyl sulfide (CEES), to understand the effect of solvent polarity on adsorption. Further, CEES and real HD were subsequently adsorbed and removed from aqueous solutions using ZIF-8 or ZIF-67. The adsorption abilities of ZIF-8 and ZIF-67 positively correlated with the polarity of the solvent. In addition, 97% of CEES (2.5 mg in 1 mL) was rapidly adsorbed by ZIF-8 and ZIF-67 within 1 min at 25 °C in a 9:1 (v/v) water/ethanol solution. ZIF-8 and ZIF-67 were also successfully fabricated on cotton, which was removed more than 95% of contaminants from substrates contaminated with the HD simulant. We believe that this work will encourage the development of ZIFs for chemical warfare defense. Image 1 • Two isostructural ZIF-8 and ZIF-67 were used to adsorb sulfur mustard from an aqueous environment. • Porous ZIF-8 and ZIF-67 cotton cloth composites were prepared. • ZIF-8 and ZIF-67 cotton cloth composites are practical systems for removal of sulfur mustard. [ABSTRACT FROM AUTHOR]