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621.
Myocardial damage caused by the newly emerged coronavirus (SARS-CoV-2) infection is one of the key determinants of COVID-19 severity and mortality. SARS-CoV-2 entry to host cells is initiated by binding with its receptor, angiotensin-converting enzyme (ACE) 2, and the ACE2 abundance is thought to reflect the susceptibility to infection. Here, we report that ibudilast, which we previously identified as a potent inhibitor of protein complex between transient receptor potential canonical (TRPC) 3 and NADPH oxidase (Nox) 2, attenuates the SARS-CoV-2 spike glycoprotein pseudovirus-evoked contractile and metabolic dysfunctions of neonatal rat cardiomyocytes (NRCMs). Epidemiologically reported risk factors of severe COVID-19, including cigarette sidestream smoke (CSS) and anti-cancer drug treatment, commonly upregulate ACE2 expression level, and these were suppressed by inhibiting TRPC3-Nox2 complex formation. Exposure of NRCMs to SARS-CoV-2 pseudovirus, as well as CSS and doxorubicin (Dox), induces ATP release through pannexin-1 hemi-channels, and this ATP release potentiates pseudovirus entry to NRCMs and human iPS cell-derived cardiomyocytes (hiPS-CMs). As the pseudovirus entry followed by production of reactive oxygen species was attenuated by inhibiting TRPC3-Nox2 complex in hiPS-CMs, we suggest that TRPC3-Nox2 complex formation triggered by panexin1-mediated ATP release participates in exacerbation of myocardial damage by amplifying ACE2-dependent SARS-CoV-2 entry.  相似文献   
622.
The effect of presence of silver nanoparticles in pure N-methyl-2-pyrrolidone(NMP) solvent for ethylene gas absorption in an experimental pressure decaying setup has been investigated. All experiments were performed at temperatures of 278.15 K, 298.15 K and 328.15 K and different pressures(up to ethylene dew point) as well as different concentrations of silver nanoparticles(0.05 g·L~(-1) and 0.1 g·L~(-1)). The kinetic data of absorption, Henry's law constants, and heat of absorption were calculated. Comparison of the pure solvent and the nanofluids absorption results revealed that the presence of small amounts of nanoparticles could improve the absorption performance between 1.5%-18%. Finally, the effect of temperature, pressure, and nanoparticle concentration on the equilibrium results were investigated.  相似文献   
623.
In the traditional (kimoto) method of sake (Japanese rice wine) brewing, Saccharomyces cerevisiae yeast cells are exposed to lactate, which is produced by lactic acid bacteria in the seed mash. Lactate promotes the appearance of glucose-repression-resistant [GAR+] cells. Herein, we compared the resistance to glucose repression among kimoto, industrial, and laboratory yeast strains. We observed that the frequencies of the spontaneous emergence of [GAR+] cells among the kimoto strains were higher than those among the industrial and laboratory strains. The fermentation ability of a kimoto yeast (strain U44) was lower than that of an industrial strain (K701), as [GAR+] cells generally showed slower ethanol production. The addition of lactate decreased the fermentation abilities of the K701 strain by increasing the number of [GAR+] cells, but it did not affect those of the U44 strain. These results suggest that lactate controlled fermentation by promoting the appearance of [GAR+] cells in the industrial sake strains but not in the kimoto strains.  相似文献   
624.
Ocular inflammation is commonly associated with eye disease or injury. Effective and sustained ocular delivery of therapeutics remains a challenge due to the eye physiology and structural barriers. Herein, we engineered a photocrosslinkable adhesive patch (GelPatch) incorporated with micelles (MCs) loaded with loteprednol etabonate (LE) for delivery and sustained release of drug. The engineered drug loaded adhesive hydrogel, with controlled physical properties, provided a matrix with high adhesion to the ocular surfaces. The incorporation of MCs within the GelPatch enabled solubilization of LE and its sustained release within 15 days. In vitro studies showed that MC loaded GelPatch supported cell viability and growth. In addition, subcutaneous implantation of the MC loaded GelPatch in rats confirmed its in vivo biocompatibility and stability within 28 days. This non-invasive, adhesive, and biocompatible drug eluting patch can be used as a matrix for the delivery and sustained release of hydrophobic drugs.  相似文献   
625.
[Fe]-hydrogenase catalyzes the heterolytic cleavage of H2 and reversible hydride transfer to methenyl-tetrahydromethanopterin. The iron-guanylylpyridinol (FeGP) cofactor is the prosthetic group of this enzyme, in which mononuclear Fe(II) is ligated with a pyridinol and two CO ligands. The pyridinol ligand fixes the iron by an acyl carbon and a pyridinol nitrogen. Biosynthetic proteins for this cofactor are encoded in the hmd co-occurring (hcg) genes. The function of HcgB, HcgC, HcgD, HcgE, and HcgF was studied by using structure-to-function analysis, which is based on the crystal structure of the proteins and subsequent enzyme assays. Recently, we reported the catalytic properties of HcgA and HcgG, novel radical S-adenosyl methionine enzymes, by using an in vitro biosynthesis assay. Here, we review the properties of [Fe]-hydrogenase and the FeGP cofactor, and the biosynthesis of the FeGP cofactor. Finally, we discuss the expected engineering of [Fe]-hydrogenase and the FeGP cofactor.  相似文献   
626.
Kinetics of change in the concentration of lipid hydroperoxides (LOOH) and carbonyls (LCO) were simultaneously investigated during peroxidation of canola and olive oils at 90°C. Depending essentially on the fatty acid compositions, the canola and olive oils exhibited one-step and two-step, respectively, multiphase peroxidations before attaining the typical termination phase. Higher and lower rates of the LOOH formation and decomposition, respectively, in the second than in the first step of the canola oil peroxidation were attributed to the dominant peroxidation of linolenic acid in the first step, and the added peroxidation of oleic and linoleic acids in the second step. The kinetics of change in [LCO], which was affected by the potency of constituting antioxidative compounds, indicated that the canola oil would be safe to use till the end of the first peroxidation step whereas the olive oil should be discarded at its induction period.  相似文献   
627.
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