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Background and objective Human periodontal ligament cells (HPDLCs) express transforming growth factor-β1 (TGF-β1) that regulates differentiation and proliferation, and plays key roles in homeostasis of PDL tissue. Transgelin is a cytoskeleton-associated protein with an Smad-binding element in its gene promoter region. In this study, we examined the localization and potential function of transgelin in PDL tissue and cells. Material and methods Microarray analysis of HPDLC lines (2-14, 2-23 and 2-52) was performed. Expression of transgelin in HPDLCs was examined by quantitative reverse transcription-polymerase chain reaction, immunofluorescence staining and western blot analysis. Effects of TGF-β1 and its signaling inhibitor, SB431542, on transgelin expression in HPDLCs were examined by western blot analysis. The effects of transgelin knockdown by small interfering RNA (siRNA) on HPDLC proliferation stimulated by TGF-β1 were assessed by WST-1 assay. Results In microarray and quantitative reverse transcription-polymerase chain reaction analyses, the expression levels of transgelin (TAGLN) in 2-14 and 2-23 cells, which highly expressed PDL markers such as periostin (POSTN), tissue non-specific alkaline phosphatase (ALPL), α-smooth muscle actin (ACTA2) and type I collagen A1 (COL1A1), was significantly higher than those in 2-52 cells that expressed PDL markers weakly. Immunohistochemical and immunofluorescence staining revealed expression of transgelin in rat PDL tissue and HPDLCs. In HPDLCs, TGF-β1 treatment upregulated transgelin expression, whereas inhibition of the type 1 TGF-β1 receptor by SB431542 suppressed this upregulation. Furthermore, TAGLN siRNA transfection did not promote the proliferation of HPDLCs treated with TGF-β1. The expression levels of CCNA2 and CCNE1, which regulate DNA synthesis and mitosis through the cell cycle, were also not upregulated in HPDLCs transfected with TAGLN siRNA. Conclusion Transgelin is expressed in PDL tissue and might have a role in HPDLC proliferation induced by TGF-β1 stimulation.

The statistical distributions of the number of simultaneously emitted secondary electrons (SE’s) from a thin carbon foil have been measured with frozen-charged H 0 and H + projectiles of 2.5–3.5 MeV. In this experiment, the forward- and backward-emitted electrons have been measured simultaneously together with foil-transmitted particles using a list-mode data taking system in order to investigate their correlation. From the two-dimensional spectra of the emitted SE’s, we have derived the probability distributions of the SE emission, P ( n f , n b ) , where n f and n b represent the number of SE’s emitted simultaneously in the forward and backward directions, respectively. Compared with those for the H + penetration, the emission probabilities for the H 0 penetration exhibit quite different n f - and n b -dependence. Firstly, P ( n f = 0 , n b = 0 ) takes a remarkably large value. Secondly, among P ( n f , n b ) ’s with n f + n b = ( constant ) , P ( n f ≠ 0 , n b = 0 ) and P ( n f = 0 , n b ≠ 0 ) become the largest and the second largest probabilities. In contrast, such events that SE’s are emitted in both of the forward and backward directions happen with significantly smaller probabilities. These trends are common to all projectile energies measured and seem to be explained by the predominance of the high energy internal SE production for the H 0 penetration due to the screening effect of its bound electron.

This study reports the possibility of electrostatic micromanipulation of a conductive/dielectric particle using a single probe. The manipulation system consists of three objects: a conductive probe as a manipulating tool, a conductive plate as a substrate, and a conductive/dielectric particle that dubs as a micro-particle. For a conductive particle, a micromanipulation technique by applying accelerating and decelerating voltage with high switching rate is developed. We theoretically determine the desired voltage as the function of time by boundary element method, and experimentally verify the voltage effectively works with a 30-micrometer-in-diameter solder particle. For a dielectric particle, we experimentally demonstrate the successful picking-up of a 60-micrometer-in-diameter dielectric particle (phenol, polystyrene) from the substrate by electrostatic force. Besides, especially for a polystyrene particle, we observe the phenomenon of a micro-particle going back and forth between the substrate and the probe-tip like a micro-dribble even when just the constant voltage is applied. We discuss the possible mechanism of this interesting phenomenon and the feasibility of electrostatic manipulation for a dielectric micro-particle.

The relationship between blood levels of nitric oxide (NO)-related compounds in patients with congenital heart defects (CHD) and degree of pulmonary hypertension (PH) has not yet been described.Thirty-six patients (aged 6 months to 19 years) with CHD were divided into three groups on the basis of their hemodynamic characteristics: group 1 (control, n = 5), left-to-right shunt (-) without PH (pulmonary to systemic artery peak pressure ratio, Pp/Ps0.4); group 2 (n = 14), left-to-right shunt (+) without PH; group 3 (n = 17), left-to-right shunt (+) with PH (Pp/Ps0.4). Blood samples were obtained from the right atrium, pulmonary artery, left atrium or pulmonary capillary wedge and aorta during cardiac catheterization. All NO-related compounds in whole blood were measured by chemiluminescent assay using Sievers NO analyzer.The sampling site had no significant impact on NO-related compound levels. However, the patients with PH (group 3) had significantly higher (P0.01) blood levels of NO-related compounds (117.3 +/- 14.7 mumol/L) than the patients without PH (groups 1 and 2, 23.9 +/- 3.2 and 38.4 +/- 4.8 mumol/L, respectively). In addition, pulmonary artery resistance (Rp) values of less than 6 Wood U/m2 were directly correlated with levels of NO-related compounds, whereas Rp values greater than 6 Wood U/m2 were inversely correlated with blood levels of NO-related compounds.The present results suggest that the hemodynamic status of the pulmonary circulation in CHD affects, at least partly, blood levels of NO-related compounds.

A basic research study for improvement of plasma-sprayed zirconia coatings has been conducted. The contact angle and surface tension of the molten manganese/zirconia-yttria ceramic system were measured at 1573 K by the sessile drop method, suggesting that molten manganese would spontaneously infiltrate open pores in zirconia coatings. Structure and elementary composition development of zirconia ceramics caused by reaction with manganese were examined by using scanning electron microscopy (SEM), an electron probe microanalyzer (EPMA), and an X-ray diffractometer (XRD). Manganese not only stabilized cubic zirconia but also contributed to the growth and volume increase of zirconia particles. In this article, the mechanism of making zirconia coatings dense with manganese is discussed based on the results of experiments.

The post-illumination photohemolysis of human red blood cells was used as a model system for studying membrane damage sensitized by various phthalocyanine sulfonates. With a constant fluence and photolysis time at 670 ± 10 nm and with a fixed optical density of the sensitizer, the percentage of hemolysis was measured as a function of time after illumination; and from the usual sigmoidal shaped curves, the times for 50% hemolysis were determined. The most effective central cation was Al, followed by Zn; the metal-free compound and those containing the paramagnetic ions Cu, Fe and Co were inactive. The sensitizer bound to the red blood cells was found to be effective for photohemolysis. Studies of the Al compound in 98.0% deuterated media (as measured by NMR) showed a definite deuterium isotope effect, suggesting the participation of singlet oxygen. This result was supported by the large protective effects of 3.3 raM and 13.3 mM tryptophan present during photolysis. Tryptophan reacts rapidly with singlet oxygen and with OH radicals. The much smaller effects observed with the same concentrations of mannitol and glycerol, OH radical scavengers which do not react with singlet oxygen, are consistent with the predominant role of singlet oxygen in photohemolysis sensitized by Al phthalocyanine sulfonate.

The detection and monitoring of strains of plant pathogens resistant to chemicals became of concern only recently, with the introduction of fungicides and bactericides that are highly specific, partially systemic, and very effective. Agriculturists have been fortunate in having had no resistance problems to contend with during the long period when sulfurs, copper, mercuries, dithiocarbamates, captan and similar nonsystemic fungicides and soil fumigants were in extensive use. Temporary resistance or adaptation of plant pathogens to copper was detected, but these resistant pathogens lost their resistance once they were allowed to grow on media free of the chemical (Parry and Wood, 1959). Thus, temporary adaptation of plant pathogens to some fungicides was not related to or correlated with any loss in their efficacy in controlling diseases. Decades and even centuries of repeated applications with these chemicals produced no evidence that they would fail to protect crops against loss to diseases because of the development of resistance. Concern about fungicide resistance and methods for determining resistance came with the discovery by Harding (1962) that control of Penicillium on citrus fruit was being lost through the development of resistance to ortho-phenylphenate and biphenyl.