Instability Phenomenon in Dip-Coating Process for Self-Assembly of Fine Particles and Design Countermeasures

The self-assembly of fine particles is a promising process for the production of nano-structures. In this process, aqueous suspension is often used. The spreading of the suspension on the substrate is a complex phenomenon that sometimes causes problems of instability. This paper discusses the instability phenomenon and proposes countermeasures from various aspects. It was found that special attention should be paid to the pattern design of site-selective assembly. Finally, complex structures made of particles of different sizes and materials are shown to demonstrate the improved stability after repeated dip-coating

Tongue Cancer Cell-Derived CCL20 Induced by Interaction With Macrophages Promotes CD163 Expression on Macrophages

BackgroundCD163-positive macrophages contribute to the aggressiveness of oral squamous cell carcinoma. We showed in a previous report that CD163-positive macrophages infiltrated not only to the cancer nest but also to its surrounding epithelium, depending on the presence of stromal invasion in tongue carcinogenesis. However, the role of intraepithelial macrophages in tongue carcinogenesis remains unclear. In this study, we assessed the biological behavior of intraepithelial macrophages on their interaction with cancer cells.Materials and MethodsWe established the indirect coculture system (intraepithelial neoplasia model) and direct coculture system (invasive cancer model) of human monocytic leukemia cell line THP-1-derived CD163-positive macrophages with SCC25, a tongue squamous cell carcinoma (TSCC) cell line. Conditioned media (CM) harvested from these systems were analyzed using cytokine array and enzyme-linked immunosorbent assay and extracted a specific upregulated cytokine in CM from the direct coculture system (direct CM). The correlation of both this cytokine and its receptor with various clinicopathological factors were evaluated based on immunohistochemistry using clinical samples from 59 patients with TSCC. Moreover, the effect of this cytokine in direct CM on the phenotypic alterations of THP-1 was confirmed by real-time polymerase chain reaction, western blotting, immunofluorescence, and transwell migration assay.ResultsIt was shown that CCL20 was induced in the direct CM specifically. Interestingly, CCL20 was produced primarily in SCC25. The expression level of CCR6, which is a sole receptor of CCL20, was higher than the expression level of SCC25. Our immunohistochemical investigation showed that CCL20 and CCR6 expression was associated with lymphatic vessel invasion and the number of CD163-positive macrophages. Recombinant human CCL20 induced the CD163 expression and promoted migration of THP-1. We also confirmed that a neutralizing anti-CCL20 antibody blocked the induction of CD163 expression by direct CM in THP-1. Moreover, ERK1/2 phosphorylation was associated with the CCL20-driven induction of CD163 expression in THP-1.ConclusionsTongue cancer cell-derived CCL20 that was induced by interaction with macrophages promotes CD163 expression on macrophages

Social robot for older adults with cognitive decline: a preliminary trial

The number of older adults living alone is rapidly increasing. Loneliness in older adults not only degrade their quality of life but also causes troubles such as heavy burden on the medical staff, especially when cognitive decline is present. Social robots could be used in several ways to reduce such problems. As a first step towards this goal, we introduced conversation robots into the homes of older adults with cognitive decline to evaluate the robot’s availability and acceptance during several months. The study involved two steps, one for evaluating the robustness of the proposed robotic system, and the second one to examine the long-term acceptance of social robots by older adults with cognitive decline living alone. Our data shows that after several weeks of human-robot interaction, the participants continued to use the robot and successfully integrated them into their lives. These results open the possibility of further research involving how sustained interaction can be achieved, as well as which factors contributed to the acceptance of the robot

The amino acid at position 624 in the glycoprotein of SFTSV (severe fever with thrombocytopenia virus) plays a critical role in low-pH-dependent cell fusion activity

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a novel phlebovirus responsible for causing an emerging zoonotic disease. We previously established subclones from SFTSV strain YG1 based on differences in low-pH-dependent cell fusion activities and found two amino acid substitutions, Y328H and R624W, in the envelope glycoprotein (GP) of high fusion subclones. In this study, we show that transiently expressed GP with the R624W mutation, but not the Y328H mutation, induced cell fusion under acidic conditions. GP possessing either tryptophan, serine, glycine or aspartic acid at position 624 induced cell fusion, whereas GP possessing basic amino acids such as arginine or lysine did not induce cell fusion. These results indicated that the amino acid at position 624 has an important role for inducing low-pH-dependent cell fusion

Inhibition of the Fermentation of Propionate to Methane by Hydrogen, Acetate, and Propionate

Inhibition of the fermentation of propionate to methane and carbon dioxide by hydrogen, acetate, and propionate was analyzed with a mesophilic propionate-acclimatized sludge that consisted of numerous flocs (size, 150 to 300 μm). The acclimatized sludge could convert propionate to methane and carbon dioxide stoichiometrically without accumulating hydrogen and acetate in a propionate-minimal medium. Inhibition of propionate utilization by propionate could be analyzed by a second-order substrate inhibition model (shown below) given that the substrate saturation constant, K(s), was 15.9 μM; the substrate inhibition constant, K(i), was 0.79 mM; and the maximum specific rate of propionate utilization, q(m), was 2.15 mmol/g of mixed-liquor volatile suspended solids (MLVSS) per day: q(s) = q(m)S/[K(s) + S + (S(2)/K(i))], where q(s) is the specific rate of propionate utilization and S is the initial concentration of undissociated propionic acid. For inhibition by hydrogen and acetate to propionate utilization, a noncompetitive product inhibition model was used: q(s) = q(m)/[1 + (P/K(p))(n)], where P is the initial concentration of hydrogen or undissociated acetic acid and K(p) is the inhibition constant. Kinetic analysis gave, for hydrogen inhibition, K(p(H(2))) = 0.11 atm (= 11.1 kPa, 71.5 μM), q(m) = 2.40 mmol/g of MLVSS per day, and n = 1.51 and, for acetate inhibition, K(p(HAc)) = 48.6 μM, q(m) = 1.85 mmol/g of MLVSS per day, and n = 0.96. It could be concluded that the increase in undissociated propionic acid concentration was a key factor in inhibition of propionate utilization and that hydrogen and acetate cooperatively inhibited propionate degradation, suggesting that hydrogenotrophic and acetoclastic methanogens might play an important role in enhancing propionate degradation to methane and carbon dioxide

Effect of cardiac glycosides on action potential characteristics and contractility in cat ventricular myocytes: role of calcium overload

ABSTRACT There is increasing evidence that cardiac glycosides act through mechanisms distinct from inhibition of the sodium pump but which may contribute to their cardiac actions. To more fully define differences between agents indicative of multiple sites of action, we studied changes in contractility and action potential (AP) configuration in cat ventricular myocytes produced by six cardiac glycosides (ouabain, ouabagenin, dihydroouabain, actodigin, digoxin, and resibufogenin). AP shortening was observed only with ouabain and actodigin. There was extensive inotropic variability between agents, with some giving full inotropic effects before automaticity occurred whereas others produced minimal inotropy before toxicity. AP shortening was not a result of alterations in calcium current or the inward rectifier potassium current, but correlated with an increase in steady-state outward current (I ss ), which was sensitive to KB-R7943, a Na ϩ -Ca 2ϩ exchange (NCX) inhibitor. Interestingly, I ss was observed following exposure to ouabain and dihydroouabain, suggesting that an additional mechanism is operative with dihydroouabain that prevents AP shortening. Further investigation into differences in inotropy between ouabagenin, dihydroouabain and ouabain revealed almost identical responses under AP voltage clamp. Thus all agents appear to act on the sodium pump and thereby secondarily increase the outward reverse mode NCX current, but the extent of AP duration shortening and positive inotropy elicited by each agent is limited by development of their toxic actions. The quantitative differences between cardiac glycosides suggest that mechanisms independent of sodium pump inhibition may result from an altered threshold for calcium overload possibly involving direct or indirect effects on calcium release from the sarcoplasmic reticulum