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A detailed understanding of how spaceflight affects human health is essential for long-term space exploration. Liquid biopsies allow for minimally-invasive multi-omics assessments that can resolve the molecular heterogeneity of internal tissues. Here, we report initial results from the JAXA Cell-Free Epigenome Study, a liquid biopsy study with six astronauts who resided on the International Space Station (ISS) for more than 120 days. Analysis of plasma cell-free RNA (cfRNA) collected before, during, and after spaceflight confirms previously reported mitochondrial dysregulation in space. Screening with 361 cell surface marker antibodies identifies a mitochondrial DNA-enriched fraction associated with the scavenger receptor CD36. RNA-sequencing of the CD36 fraction reveals tissue-enriched RNA species, suggesting the plasma mitochondrial components originated from various tissues. We compare our plasma cfRNA data to mouse plasma cfRNA data from a previous JAXA mission, which had used on-board artificial gravity, and discover a link between microgravity and the observed mitochondrial responses. It has been reported that a spaceflight causes mitochondrial stress in astronauts. Here the authors suggest that mitochondrial components are released into the plasma during spaceflight as components of CD36-marked extracellular vesicles (EVs). [ABSTRACT FROM AUTHOR]

Microgravity induces skeletal muscle atrophy, particularly in the soleus muscle, which is predominantly composed of slow-twitch myofibre (type I) and is sensitive to disuse. Muscle atrophy is commonly known to be associated with increased production of reactive oxygen species. However, the role of NRF2, a master regulator of antioxidative response, in skeletal muscle plasticity during microgravity-induced atrophy, is not known. To investigate the role of NRF2 in skeletal muscle within a microgravity environment, wild-type and Nrf2-knockout (KO) mice were housed in the International Space Station for 31 days. Gene expression and histological analyses demonstrated that, under microgravity conditions, the transition of type I (oxidative) muscle fibres to type IIa (glycolytic) was accelerated in Nrf2-KO mice without affecting skeletal muscle mass. Therefore, our results suggest that NRF2 affects myofibre type transition during space flight. Hayashi et al. report on the effect of space flight on muscle mass, fibre size and type, composition and gene signalling of muscle in WT and Nrf2-KO mice. Their results demonstrate a key role of NRF2 in maintaining the slow-type fibres of soleus muscle during space flight and in microgravity environments. [ABSTRACT FROM AUTHOR]

Spaceflight causes a decrease in skeletal muscle mass and strength. We set two murine experimental groups in orbit for 35 days aboard the International Space Station, under artificial earth-gravity (artificial 1 g; AG) and microgravity (μg; MG), to investigate whether artificial 1 g exposure prevents muscle atrophy at the molecular level. Our main findings indicated that AG onboard environment prevented changes under microgravity in soleus muscle not only in muscle mass and fiber type composition but also in the alteration of gene expression profiles. In particular, transcriptome analysis suggested that AG condition could prevent the alterations of some atrophy-related genes. We further screened novel candidate genes to reveal the muscle atrophy mechanism from these gene expression profiles. We suggest the potential role of Cacng1 in the atrophy of myotubes using in vitro and in vivo gene transductions. This critical project may accelerate the elucidation of muscle atrophy mechanisms. [ABSTRACT FROM AUTHOR]

Supported Pt catalysts were prepared using several kinds of TiO supports different in the crystallite size in the range of 10-500 nm and their catalytic activity was tested for the liquid-phase hydrogenation of 3-nitrostyrene, nitrobenzene, and styrene. With Pt on smaller TiO crystallites (nanocrystals), the selectivity to vinylaniline was improved in the hydrogenation of 3-nitrostyrene (regioselective hydrogenation) and the selectivity to aniline was promoted in the hydrogenation of a mixture of nitrobenzene and styrene (chemoselective hydrogenation). The effects of TiO crystallite size were discussed on the basis of the results of turnover frequency and FTIR of CO adsorbed on dispersed Pt particles. Low coordinated and/or electron-rich Pt sites should be formed on the surface of nanocrystal TiO supports. Nanocrystal TiO support is an important factor for controlling and improving the catalytic performance of dispersed Pt particles. Graphical Abstract: Smaller TiO crystallites give rougher Pt crystal planes on the surface of Pt particles, beneficial for the hydrogenation of nitro group than vinyl group.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Diphenyl carbonate (DPC) was synthesized from phenol and dense phase CO2 in the presence of CCl4 and K2CO3 using different catalysts of ZnCl2, ZnBr2, Lewis acid ionic liquids including 1-butyl-3-methylimidazolium chloride (BMIMCl) and bromide (BMIMBr). It was found that K2CO3 was not required, ZnCl2 and ZnBr2 were similar in the catalytic performance, and the use of BMIMCl and BMIMBr was not effective for the production of DPC. For the reactions with ZnCl2 in CCl4, the effects of such reaction variables as temperature, CO2 pressure, the amount of ZnCl2, and the volume of CCl4 were studied in detail. It was shown that the pressure was less influential while a larger amount of ZnCl2, a smaller volume of CCl4, and a low temperature of around 100°C were beneficial for the synthesis of DPC. On the basis of the results obtained, possible reaction mechanisms were discussed. [ABSTRACT FROM AUTHOR]

This work deals with the dealumination of zeolite beta under different conditions to optimize its catalytic performance. The dealumination was carried out either using oxalic or tartaric acid solution of different pH values or steaming up to 500 °C. The dealuminated zeolite samples were characterized using X-ray diffraction, N2-physisorption, ICP, 27Al NMR and NH3-TPD. Their catalytic activities were studied for acylation reaction of 2-methoxy naphthalene or naphthalene with acetic anhydride and esterification of benzyl alcohol with hexanoic acid. Among the dealuminated samples examined, those treated with oxalic acid or tartaric acid at pH 2 showed high activity. The high activity can be correlated with the relative increase in the amount of strong acid sites and with the enhanced accessibility of the reactants to the active sites, which are caused by removal of extra-framework Al species on the acid treatments. [ABSTRACT FROM AUTHOR]

Smectites containing magnesium and/or nickel in the lattice were found to be excellent heterogeneous catalysts for the concurrent synthesis of dimethyl carbonate and ethylene glycol by transesterification of ethylene carbonate with methanol. The catalytic activity strongly depends on the elemental composition of the catalysts and is correlated with the number of moderately basic sites present on the catalyst. [ABSTRACT FROM AUTHOR]

The reaction of propylene oxide and carbon dioxide to propylene carbonate was carried out using Mg-, Ni- and Mg-Ni-containing smectite catalysts which contain different amounts of alkali atoms such as sodium, potassium and lithium. These catalysts are highly active and selective for this reaction. The catalytic activity strongly depends on the elemental composition of the catalyst used. Particularly the amount of alkali atoms incorporated in the catalyst is the most important factor governing the catalytic performance. The most active catalyst among those prepared in the present study shows a turnover number of 105 mmol/g for the propylene carbonate formation, which is the highest turnover number compared with those reported so far (10 mmol/g) for the title reaction. [ABSTRACT FROM AUTHOR]

For the title reaction, Cu/ZnO catalysts prepared from aurichalcite were more active than those prepared from other precursors. Selectivity to ethyl acetate over Cu/ZnO was much higher than that over Cu/SiO [ABSTRACT FROM AUTHOR]

The CuO crystallite size of the catalysts obtained from aurichalcite greatly depends on the heating rate of calcination for highly active and selective Cu/ZnO catalyst was prepared by reduction with methanol at 443 K for 17 h. [ABSTRACT FROM AUTHOR]

At lower temperatures or in the presence of O, metal oxides showed higher turnover frequency for the decomposition of NO than corresponding metal ion exchanged ZSM-5. [ABSTRACT FROM AUTHOR]

Pyridine was methylated selectively to 2-picoline with CO−H and with CO−H over a Ni catalyst. 2,6-lutidine was produced via the methylation of 2-picoline. [ABSTRACT FROM AUTHOR]