Polymerized Laminin-332 Matrix Supports Rapid and Tight Adhesion of Keratinocytes, Suppressing Cell Migration

Laminin-332 (α3ß3γ2) (Lm332) supports the stable anchoring of basal keratinocytes to the epidermal basement membrane, while it functions as a motility factor for wound healing and cancer invasion. To understand these contrasting activities of Lm332, we investigated Lm332 matrices deposited by normal human keratinocytes and other Lm332-expressing cell lines. All types of the cells efficiently deposited Lm332 on the culture plates in specific patterns. On the contrary, laminins containing laminin ß1 and/or γ1 chains, such as Lm511 and Lm311, were not deposited on the culture plates even if secreted into culture medium. The Lm332 deposition was not inhibited by function-blocking antibodies to the α3 and α6 integrins but was inhibited by sodium selenate, suggesting that sulfated glycosaminoglycans on cell surface, e.g. heparan sulfate proteoglycans, might be involved in the process. HEK293 cells overexpressing exogenous Lm332 (Lm332-HEK) almost exclusively deposited Lm332 on the plates. The deposited Lm332 matrix showed a mesh-like network structure as analyzed by electron microscopy, suggesting that Lm332 was highly polymerized. When biological activity was analyzed, the Lm332 matrix rather suppressed the migration of keratinocytes as compared with purified Lm332, which highly promoted the cell migration. The Lm332 matrix supported adhesion of keratinocytes much more strongly and stably than purified Lm332. Integrin α3ß1 bound to the Lm332 matrix at a three times higher level than purified Lm332. Normal keratinocytes prominently showed integrin α6ß4-containing, hemidesmosome-like structures on the Lm332 matrix but not on the purified one. These results indicate that the polymerized Lm332 matrix supports stable cell adhesion by interacting with both integrin α6ß4 and α3ß1, whereas unassembled soluble Lm332 supports cell migration

Molecular dynamics simulation of fluorination effect for solvation of trifluoromethylbenzoic acid isomers in supercritical carbon dioxide

金沢大学大学院自然科学研究科生産プロセスA molecular dynamics (MD) simulation was applied to carbon dioxide + trifluoromethylbenzoic acid isomer and carbon dioxide + methylbenzoic acid isomer systems to investigate the interactions between carbon dioxide and the solutes. The pair correlation functions between the carbon dioxide and trifluoromethyl group or methyl group in the solutes were calculated to study the fluorination effect of solvation. As a result, it was found that the interactions between carbon dioxide and trifluoromethyl group in trifluoromethylbenzoic acid isomers were stronger than those between carbon dioxide and the methyl group in methylbenzoic acid isomers. The simulation results had the same tendency as the experimental solubility enhancements and coincided with the trend of the interaction parameters of the Peng-Robinson equation of state that were determined from the solubility data. © 2005 Taylor & Francis Group Ltd

Involvement of interleukin-8 in dialysis-related arthritis

Involvement of interleukin-8 in dialysis-related arthritis. To elucidate the role of interleukin (IL)-8, a chemotactic factor for neutrophils, in dialysis-related arthritis (DRA) of patients on long-term hemodialysis, the concentration of IL-8 was measured in the synovial fluids of DRA patients with acute arthralgia and joint swelling, and was compared with those in patients with rheumatoid arthritis (RA) and patients with osteoarthritis (OA). We noted a marked elevation of IL-8 in the joint fluids of patients with DRA and RA as compared with OA. Furthermore, to determine the role of IL-8 in synovitis, we examined the in vivo effect of intra-articular injection of human recombinant IL-8 on leukocyte infiltration into the joint space of rabbits. A single injection of IL-8 to the joints of rabbits induced rapid infiltration of neutrophils into the joint space and synovial tissues, which reached a maximum in four hours. The oral administration of indometacin farnesil (a prodrug that is converted to indomethacin after intestinal absorption) before the injection of IL-8 alleviated the infiltration of neutrophils. When human synovial cells were incubated with tumor necrosis factor (TNF)-α, the expression of IL-8 mRNA and IL-8 production in the cultured synovial cells were increased. The TNF-α-stimulated expression of IL-8 mRNA and IL-8 production in the cultured synovial cells were markedly inhibited by dexamethasone. In conclusion, IL-8 levels were markedly elevated in the joint fluids of patients with DRA. Interleukin-8 released from synovial cells may be an important factor to induce acute inflammation in DRA. Dexamethasone and indomethacin may be effective for DRA by inhibiting the production and chemotactic actions of IL-8, respectively

Utilization of Chinese fast-growing trees and the effect of alternating lamination using mixed-species eucalyptus and poplar veneers

Over the past few decades, the sustainable forest area in China has increased remarkably, with 2400 million cubic meters of eucalyptus produced in 2018 in Guangxi which is the largest plantation area in China. In this study, the effect of alternating lamination using soft poplar veneers and hard eucalyptus veneers, on the mechanical properties of laminated veneer lumber (LVL), was examined. Eucalyptus and poplar veneers were imported from China to Japan to manufacture the LVL. For both eucalyptus and poplar veneers, the pith side (innerwood) sheets were lighter in density than the bark side (outerwood) sheets. The specific Young’s modulus of alternating LVL with hard eucalyptus veneers and soft poplar veneers was smaller than that of the mono-species LVL of eucalyptus and poplar. Strain distributions were obtained with the compression test by using the digital image correlation method. Normal strains showed that the hard eucalyptus layer behaved as a thin plate, whereas the soft poplar layer mitigated the movement of the hard eucalyptus layer. Alternating lamination decreased the variation in the elastic modulus of LVL made from fast-growing species. Therefore, the soft layers mitigated the movement of the hard layers, which had large variations in mechanical properties

Measurement and correlation of solubilities for trifluoromethylbenzoic acid isomers in supercritical carbon dioxide

金沢大学大学院自然科学研究科生産プロセスThe solubilities of 2-, 3- and 4-trifluoromethylbenzoic acids in supercritical carbon dioxide were measured at 308.2, 313.2 and 323.2 K by a flow-type apparatus. The pressure range of the measurement was from 9 to 23 MPa. The enhancements of solubility by fluorination were markedly observed for 2- and 3-trifluoromethylbenzoic acids. The solubilities of 4-trifluoromethylbenzoic acids are almost the same as those of 4-methylbenzoic acid. The experimental data were correlated by the Peng-Robinson equation of state. The correlated results show good agreement with the experimental data by adjusting binary interaction parameters. The results can represent the tendency of solubility enhancement. The interaction parameter between carbon dioxide and 3-trifluoromethylbenzoic acid is smaller than that between carbon dioxide and 2-trifluoromethylbenzoic acid or methylbenzoic acid isomers. While the estimated sublimation pressure for 4-trifluoromethylbenzoic acid is smaller than those for the other compounds, the solubilities of 4-trifluoromethylbenzoic acids are almost the same as those of 4-methylbenzoic acid. The interaction parameter between carbon dioxide and 4-trifluoromethylbenzoic acid show the negative values. This fact indicates that the interaction between carbon dioxide and 4-trifluoromethylbenzoic acid is stronger than those between carbon dioxide and the other compounds. © 2004 Elsevier B.V. All rights reserved

Measurement of solubilities for rhodium complexes and phosphine ligands in supercritical carbon dioxide

金沢大学大学院理工研究域自然システム学系The solubilities of phosphine ligands and rhodium (Rh) complexes in supercritical carbon dioxide were measured with Fourier transform infrared (FT-IR) spectroscopy at 320 and 333 K and several pressures. Triphenylphosphine (TPP) and tris(p-trifluoromethylphenyl)-phosphine (TTFMPP) were selected as ligands for the Rh complex. The solubilities of the fluorinated ligands and complexes were compared with those of the non-fluorinated compounds. The solubilities of ligand increased up to 10 times by the fluorination. It was found that the solubilities of Rh complexes were enhanced up to 30 times by introducing trifluoromethyl group to the ligand. The experimental data was correlated by the Chrastil equation. The correlated results were in good agreement with the experimental data. Furthermore, the solvation numbers of carbon dioxide around the ligands and Rh complexes were obtained from the slope of the Chrastil equation. The solvation number for the fluorinated compounds was about two and five times higher than those of the non-fluorinated ligand and complex, respectively. © 2007