2-IPMA Ameliorates PM2.5-Induced Inflammation by Promoting Primary Ciliogenesis in RPE Cells

Primary cilia mediate the interactions between cells and external stresses. Thus, dysregulation of primary cilia is implicated in various ciliopathies, e.g., degeneration of the retina caused by dysregulation of the photoreceptor primary cilium. Particulate matter (PM) can cause epithelium injury and endothelial dysfunction by increasing oxidative stress and inflammatory responses. Previously, we showed that PM disrupts the formation of primary cilia in retinal pigment epithelium (RPE) cells. In the present study, we identified 2-isopropylmalic acid (2-IPMA) as a novel inducer of primary ciliogenesis from a metabolite library screening. Both ciliated cells and primary cilium length were increased in 2-IPMA-treated RPE cells. Notably, 2-IPMA strongly promoted primary ciliogenesis and restored PM2.5-induced dysgenesis of primary cilia in RPE cells. Both excessive reactive oxygen species (ROS) generation and activation of a stress kinase, JNK, by PM2.5 were reduced by 2-IPMA. Moreover, 2-IPMA inhibited proinflammatory cytokine production, i.e., IL-6 and TNF-α, induced by PM2.5 in RPE cells. Taken together, our data suggest that 2-IPMA ameliorates PM2.5-induced inflammation by promoting primary ciliogenesis in RPE cells.     

Intracrystalline Diffusion in Mesoporous Zeolites

Specially synthesized extra‐large crystallites of zeolite LTA with intentionally added mesoporosity are used for an in‐depth study of guest diffusion in hierarchical nanoporous materials by the pulsed field gradient NMR technique. Using propane as a guest molecule, intracrystalline mass transfer is demonstrated to be adequately described by a single effective diffusivity resulting from the weighted average of the diffusivities in the two (micro‐ and meso‐) pore spaces. Gas‐kinetic order‐of‐magnitude estimates of the diffusivities are in satisfactory agreement with the experimental data and are thus shown to provide a straightforward means for predicting and quantifying the benefit of hierarchically structured nanoporous materials in comparison with their purely microporous equivalent.     

Increased arginase II activity contributes to endothelial dysfunction through endothelial nitric oxide synthase uncoupling in aged mice

The incidence of cardiovascular disease is predicted to increase as the population ages. There is accumulating evidence that arginase upregulation is associated with impaired endothelial function. Here, we demonstrate that arginase II (ArgII) is upregulated in aortic vessels of aged mice and contributes to decreased nitric oxide (NO) generation and increased reactive oxygen species (ROS) production via endothelial nitric oxide synthase (eNOS) uncoupling. Inhibiting ArgII with small interfering RNA technique restored eNOS coupling to that observed in young mice and increased NO generation and decreased ROS production. Furthermore, enhanced vasoconstrictor responses to U46619 and attenuated vasorelaxation responses to acetylcholine in aged vasculature were markedly improved following siRNA treatment against ArgII. These results might be associated with increased L-arginine bioavailability. Collectively, these results suggest that ArgII may be a valuable target in age-dependent vascular diseases.     

Unidirectional helical assembly via triple hydrogen bonds between chiral tris(oxazoline) and achiral tris(imidazoline)

Tris(imidazolines) are assembled via triple hydrogen bonding interactions to give rise to a stacked polymeric structure. A mixture of chiral tris(oxazoline) and achiral tris(imidazoline) generates a helical assembly in which the helical direction of the assembly is unidirectionally induced by the chirality of tris(oxazoline).     

Robust Metaheuristic Algorithm for Redundancy Optimization in Large-Scale Complex Systems

Based upon the general tabu search methodology, this paper develops a robust metaheuristic algorithm for the redundancy optimization in large-scale complex system reliability that performs a rigorous search of the “attractive” feasible space and is capable of escaping from a local solution. An illustrative example is provided and extensive computational results are reported on two test problems from the literature (Aggarwal, 1976; Shi, 1987) and also on randomly generated large-scale instances of complex systems with up to 200 components. The computational results indicate that the proposed metaheuristic algorithm possesses a superior robustness and efficiency for solving the class of hard optimization problems studied in this paper.     

An evolution compressible Stokes system in a polygon

An evolution compressible Stokes system is studied in a polygon. A lowest order corner singularity by the Laplacian operator is sorted out and an increased regularity is established in a suitable Banach space. In the lowest level, for each time the order of the corner singularity of the system is the same as that of the Laplacian. In addition, a singular function for pressure is defined and shows that the corner singularities originated from the corners of polygon may propagate along the directed streamlines.     

A study on the photophysical properties of anthracene in zeolite

The photophysical behaviours of anthracene in zeolite Y were investigated using various steady state spectroscopic methods and a picosecond time-resolved fluorescence spectroscopic technique. A ¹²⁹Xe nuclear magnetic resonance (NMR) study shows that anthracene molecules can be optimally intercalated into the supercages of Na⁺- and Cu²⁺-exchanged zeolite Y at 570 and 520 K respectively. Anthracene introduced into the supercage of Na⁺-exchanged zeolite Y shows excimeric fluorescence with a lifetime of several nanoseconds, as well as monomeric fluorescence with a lifetime of 300 ps. The excimer forms immediately on absorption of a photon. Cu²⁺-exchanged zeolite Y with anthracene intercalation shows electron spin resonance (ESR) signals and absorption bands attributable to the stable, ground state anthracene cation radical, the Cu⁺ ion and the trapped electron in the copper ion cluster, indicating charge transfer from anthracene to the Cu²⁺ ion or copper ion cluster. The excitation energy of anthracene is quenched rapidly by the presence of copper ion.     

A facile one pot synthesis of 1-alkylbenzimidazoline-2-thiones

Reactions of benziraidazoline-2-thione with alkyl halides in the presence of sodium naphthalenide in tetra-hydrofuran at room temperature under a nitrogen atmosphere afforded 1-alkyl-2-alkylthiobenzimidazoles in excellent yields, which underwent a bond cleavage between S and C of alkyl group to give excellent yields of 1-alkylbenzimidazoline-2-thiones by the treatment with an additional amount of sodium naphthalenide.     

Synthesis of Silicate Zeolite Analogues Using Organic Sulfonium Compounds as Structure‐Directing Agents

A microporous crystalline silica zeolite of the MEL structure type and three other zeolite analogues composed of germanosilicate frameworks were synthesized using tributylsulfonium, triphenylsulfonium, or tri(para‐tolyl)sulfonium as the structure‐directing agent. The germanosilicates thus obtained had ISV, ITT, or a new zeolite structure depending on the synthesis conditions. The structure of the new germanosilicate was solved using X‐ray powder diffraction data with the aid of a charge‐flipping method. The solution indicated a crystal structure belonging to the P63/mmc space group with cell parameters of a=16.2003 Å and c=21.8579 Å. After calcination, the new germanosilicate material exhibited two types of accessible micropores with diameters of 0.61 and 0.78 nm.