37 research outputs found
Effect of Rust Inhibitor in Brine on Corrosion Properties of Copper
In this study, the effects of rust inhibitors in brine on corrosion behaviors of copper were investigated by measurement of cathode and anode polarization curves and an immersion test. For rust inhibitors, benzotriazole, sodium benzoate and sodium nitrite were prepared. From measurement results of cathode and anode polarization curves, it was found that the corrosion rate of copper in the benzotriazole solution is low and a stable passive film with excellent corrosion resistance generates on the surface of copper in the solution. In the case of the sodium benzoate solution, the corrosion resistance of the passive film was inferior to that in the benzotriazole solution although the passive film generated on the surface of copper. In contrast, the passive film scarcely generated on the surface of copper in the sodium nitrite solution. The result shows that the rust preventive effect of the solution to copper is weak. Furthermore, the immersion test revealed that the benzotriazole solution has the rust preventive effect to copper. In contrast, the effect of the sodium benzoate solution is weak and that of the sodium nitrite solution is scarcely expected
Recent Progress of Flower Colour Modification by Biotechnology
Genetically-modified, colour-altered varieties of the important cut-flower crop carnation have now been commercially available for nearly ten years. In this review we describe the manipulation of the anthocyanin biosynthesis pathway that has lead to the development of these varieties and how similar manipulations have been successfully applied to both pot plants and another cut-flower species, the rose. From this experience it is clear that down- and up-regulation of the flavonoid and anthocyanin pathway is both possible and predictable. The major commercial benefit of the application of this technology has so far been the development of novel flower colours through the development of transgenic varieties that produce, uniquely for the target species, anthocyanins derived from delphinidin. These anthocyanins are ubiquitous in nature, and occur in both ornamental plants and common food plants. Through the extensive regulatory approval processes that must occur for the commercialization of genetically modified organisms, we have accumulated considerable experimental and trial data to show the accumulation of delphinidin based anthocyanins in the transgenic plants poses no environmental or health risk
Diphosphorylation of the myosin regulatory light chain enhances the tension acting on stress fibers in fibroblasts.
Regulation of the contractile force is crucial for cell migration, cell proliferation, and maintenance of cell morphology. Phosphorylation of the myosin II regulatory light chain (MRLC) is involved in these processes. To show whether the diphosphorylation of MRLC increases the tension acting on stress fibers, changes in the stiffness of fibroblasts expressing wild-type MRLC and a mutant type, which cannot be diphosphorylated, on treatment with lysophosphatidic acid (LPA) were examined by a mechanical-scanning probe microscope (M-SPM). The LPA treatment increased cellular stiffness in the wild-type MRLC expressing cells, while it had no effect on the mutated cells. Immunostaining showed that LPA stimulation induced the diphosphorylation of MRLC. These results suggest that the diphosphorylation of MRLC enhances the tension acting on stress fibers. J. Cell. Physiol. 209: 726-731, 2006. © 2006 Wiley-Liss, Inc
The 5′ untranslated region of the human cellular glutathione peroxidase gene is indispensable for its expression in COS-7 cells
AbstractWe studied the expression of the human cellular glutathione peroxidase (GPx) gene, from which a key enzyme containing selenocysteine (Scy) at the active site is produced. Expression of some human GPx gene mutants in COS-7 cells revealed that the 5′ untranslated region (utr) was necessary for expression of the GPx gene, since mutant genes having 10 base pairs (bps) at the 5′utr (the complete had 311 bps) expressed GPx at very low levels. The genes with 311 or 408 bps at the 5′utr were better expressed than those having 257 bps. The GPx gene having 133 bps at the 3′utr (80 bps shorter than the entire length) was highly expressed. This deletion did not influence expression. We constructed some mutants in which 3 bases were altered at the upstream region of the Scy UGA codon in the frame of the GPx gene, by site-directed mutagenesis. GPx expression decreased but the expression was restored. Therefore, the upstream region of the in-frame Scy codon was not essential in the Scy decoding mechanisms. Finally, the 5′utr was essential for the expression of GPx gene. However, the deletion of a part of the 3′utr and the site-directed mutation upstream of the Scy codon did not show drastic effects on the expression
SLPI facilitates cell migration by regulating lamellipodia/ruffles and desmosomes, in which Galectin4 plays an important role
To elucidate the underlying mechanism of secretory leukocyte protease inhibitor (SLPI)-induced cell migration, we compared SLPI-deleted human gingival carcinoma Ca9-22 (Delta SLPI) cells and original (wild-type: wt) Ca9-22 cells using several microscopic imaging methods and gene expression analysis. Our results indicated reduced migration of Delta SLPI cells compared to wtCa9-22 cells. The lamellipodia/dorsal ruffles were smaller and moved slower in Delta SLPI cells compared to wtCa9-22 cells. Furthermore, well-developed intermediate filament bundles were observed at the desmosome junction of Delta SLPI cells. In addition,Galectin4was strongly expressed in Delta SLPI cells, and its forced expression suppressed migration of wtCa9-22 cells. Taken together, SLPI facilitates cell migration by regulating lamellipodia/ruffles and desmosomes, in which Galectin4 plays an important role