We report here a simple and straightforward method that enables the size-controlled production of zeolitic imidazolate framework-8 in an aqueous system at room temperature. Pure single crystals with the size tuned in the range of ca. 300 nm to 3¯m in mean crystal size can be obtained and exhibit ultrahigh 4 and catalysis. 5 The zirconium(2-methylimidazole) 2 (ZIF-8), with a sodalite (SOD) zeolite-type topology, is a commercially available sample produced by BASF. ZIF-8 possesses large cages of 11.6 ¡ accessible through narrow windows of 3.4 ¡. Most syntheses of ZIFs have been reported so far include using organic solvents such as dimethylformamide (DMF), diethylformamide (DEF), methanol, and DMF/methanol. 6 The use of organic solvents is generally expensive and causes potential environmental pollution and human health problems. Simple techniques to synthesize ZIFs are required for the development of practical applications. Recently, aqueous synthesis of ZIF-8 has been reported. 7 Compared with the synthesis in organic solvents, the aqueous synthesis of ZIFs has particular advantages from economic, operational, and environmental perspectives. However, ZIF-8 prepared in aqueous systems has lower surface area than that prepared in organic systems, suggesting that the product contains dense by-products. 7 In addition, the aqueous synthesis requires excessive imidazole sources to obtain ZIF-8. 7a Further systematic understanding is required to synthesize phase pure ZIF-8 in an aqueous system.In this study, we have developed a simple and sizecontrolled synthesis of ZIF-8 using pure water. We focus on the effects of the imidazole concentration on crystal structure, mean particle size, and particle size distribution.ZIF-8 crystals were prepared from zinc nitrate hexahydrate (Zn(NO 3 ) 2 ¢6H 2 O; Zn) and 2-methylimidazole (mim) in pure water solvent. All chemicals were purchased from SigmaAldrich Chemical Co. and used as received. The molar compositions of the reaction mixtures were in the range of 1 Zn/4100 mim/2228 water. The mim/Zn molar ratio in the precursor solution ranges from 4 to 100. In all runs, to change the mim/Zn molar ratio, only the amount of mim was changed; the amounts of Zn and water were held constant. In a typical preparation, 0.744 g of Zn and 12.3 g of mim were each dissolved in 10 and 90 mL of deionized water, respectively. The former clear solution was poured into the latter clear solution under stirring. All the operations were performed at room temperature. The mixture became cloudy immediately after combining the component solutions. After stirring for 24 h, the milky colloidal dispersion was centrifuged at 6000 rpm for 10 min. The particles obtained were washed with methanol and centrifuged again; the process was repeated five times. The product was dried at 40°C for 48 h under reduced pressure. The products were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), dynamic light scattering (DLS), thermogravimetric analysis (TGA), and N 2 sorption measurem...

Although recent reports suggest that the endoplasmic reticulum (ER) stress response is induced in association with the development of inflammatory bowel disease, its role in the pathogenesis of inflammatory bowel disease remains unclear. The CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) is a transcription factor that is involved in the ER stress response, especially ER stress-induced apoptosis. In this study, we found that experimental colitis was ameliorated in CHOP-null mice, suggesting that CHOP exacerbates the development of colitis. The mRNA expression of Mac-1 (CD11b, a positive regulator of macrophage infiltration), Ero-1alpha, and Caspase-11 (a positive regulator of interleukin-1beta production) in the intestine was induced with the development of colitis, and this induction was suppressed in CHOP-null mice. ERO-1alpha is involved in the production of reactive oxygen species (ROS); an increase in ROS production, which is associated with the development of colitis in the intestine, was suppressed in CHOP-null mice. A greater number of apoptotic cells in the intestinal mucosa of wild-type mice were observed to accompany the development of colitis compared with CHOP-null mice, suggesting that up-regulation of CHOP expression exacerbates the development of colitis. Furthermore, this CHOP activity appears to involve various stimulatory mechanisms, such as macrophage infiltration via the induction of Mac-1, ROS production via the induction of ERO-1alpha, interleukin-1beta production via the induction of Caspase-11, and intestinal mucosal cell apoptosis.

Drug-induced interstitial lung disease (ILD), particularly pulmonary fibrosis, is a serious clinical concern and myofibroblasts have been suggested to have a major role, with it recently being revealed that some of these myofibroblasts are derived from lung epithelial cells through epithelial-mesenchymal transition (EMT). In this study, we examined the EMT-inducing abilities of drugs known to induce ILD clinically. EMT-like phenotypes were induced by A771726, an active metabolite of leflunomide having an inhibitory effect on dihydroorotate dehydrogenase (DHODH). Smad-interacting protein 1 (a transcription factor regulating EMT) and the Notch-signaling pathway but not transforming growth factor-b was shown to be involved in A771726-induced EMT-like phenotypes. When the cultures were supplemented with exogenous uridine, the A771726-induced EMT-like phenotypes and activation of the Notch-signaling pathway disappeared. Similarly, an A771726 analog without inhibitory activity on DHODH produced no induction, suggesting that this process is mediated through the inhibition of DHODH. In vivo, administration of leflunomide stimulated bleomycin-induced EMT-like phenomenon in pulmonary tissue, and exacerbated bleomycin-induced pulmonary fibrosis, both of which were suppressed by coadministration of uridine. Taken together, these findings suggest that leflunomide-dependent exacerbation of bleomycin-induced pulmonary fibrosis is mediated by stimulation of EMT of lung epithelial cells, providing the first evidence that drug-induced pulmonary fibrosis involves EMT of these cells.

[1] Pressure effect of self-diffusion in periclase (MgO) was investigated by molecular dynamics (MD), and viscosity variation of lower mantle periclase was predicted by employing the Nabarro-Herring model. Self-diffusion coefficients were derived directly from recorded trajectories of atoms. The MD calculations were performed at 2400-6000 K and 0-140 GPa. Migration energy (H m * ) and formation energy (H f * ) of ordinary pressure (0 GPa) are consistent with experimental data. Observed pressure dependence of self-diffusion coefficients was turned from negative with increasing pressure. The behavior of self-diffusion coefficients predicts softening of lower mantle periclase with increasing depth. We predict 1.3 times reduction of the viscosity (0.3 K/km geothermal gradient) or 2.0 times (0.6 K/km geothermal gradient).Citation: Ito, Y., and M. Toriumi (2007), Pressure effect of self-diffusion in periclase (MgO) by molecular dynamics, J. Geophys.

Choosing an option increases a person’s preference for that option. This phenomenon, called choice-based learning (CBL), has been investigated separately in the contexts of internally guided decision-making (IDM, e.g., preference judgment), for which no objectively correct answer exists, and externally guided decision making (EDM, e.g., perceptual decision making), for which one objectively correct answer exists. For the present study, we compared decision making of these two types to examine differences of underlying neural processes of CBL. As IDM and EDM tasks, occupation preference judgment and salary judgment were used, respectively. To compare CBL for the two types of decision making, we developed a novel measurement of CBL: decision consistency. When CBL occurs, decision consistency is higher in the last-half trials than in first-half trials. Electroencephalography (EEG) data have demonstrated that the change of decision consistency is positively correlated with the fronto-central beta–gamma power after response in the first-half trials for IDM, but not for EDM. Those results demonstrate for the first time the difference of CBL between IDM and EDM. The fronto-central beta–gamma power is expected to reflect a key process of CBL, specifically for IDM.