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We have recently developed an in vitro yeast reconstituted translation system, which is capable of synthesizing long polypeptides. Utilizing the system, we examined the role of eIF5A and its hypusine modification in translating polyproline sequence within long open reading frames. We found that polyproline motif inserted at the internal position of the protein arrests translation exclusively at low Mg2+ concentrations, and peptidylpolyproline-tRNA intrinsically destabilizes 80S ribosomes. We demonstrate that unmodified eIF5A essentially resolves such ribosome stalling; however, the hypusine modification drastically stimulates ability of eIF5A to rescue polyproline-mediated ribosome stalling and is particularly important for the efficient translation of the N-terminal or long internal polyproline motifs.

Sphingomyelin synthase 2 (SMS2) has attracted attention as a drug target for the treatment of various cardiovascular and metabolic diseases. The modification of a high throughput screening hit, 2-quinolone 10, enhanced SMS2 inhibition at nanomolar concentrations with good selectivity against SMS1. To improve the pharmaceutical properties such as passive membrane permeability and aqueous solubility, adjustment of lipophilicity was attempted and 1,8-naphthyridin-2-one 37 was identified as a potent and selective SMS2 inhibitor. A significant reduction in hepatic sphingomyelin levels following repeated treatment in mice suggested that compound 37 could be an effective in vivo tool for clarifying the role of SMS2 enzyme and developing the treatment for SMS2-related diseases.

Interfacial tension between edible oil and saline was measured under applied electric fields to understand the electrocapillary phenomena at the edible oil/saline interfaces. The electric responses of saline droplets in edible oil were also observed microscopically to examine the relationship between the electrocapillary phenomena and interfacial polarization. When sodium oleate (SO) was added to edible oil (SO-oil), the interfacial tension between SO-oil and saline decreased. However, no decrease was observed for additive-free oil or oleic acid (OA)-added oil (OA-oil). Microscopic observations suggested that the magnitude of interfacial polarization increased in the order of additive-free oil < OA-oil < SO-oil. The difference in electrocapillary phenomena between OA- and SO-oils was closely related to the polarization magnitude. In the case of SO-oil, the decrease in interfacial tension was remarkably larger for saline (pH 5.4~5.6) than that for phosphate-buffered saline (PBS, pH 7.2~7.4). However, no difference was observed between the electric responses of PBS and saline droplets in SO-oil. The difference in electrocapillary phenomena for PBS and saline could not be simply explained in terms of polarization magnitude. The ratio of ionized and non-ionized OA at the interfaces changed with the saline pH, possibly leading to the above difference.

Background Previous pathohistological studies demonstrated that cholesterol crystals (CCs) are frequently observed in atherosclerotic plaques, and are usually present abundantly in vulnerable plaques. However, the role of CCs in plaque destabilization, as well as their origin and composition, is unknown. Optical coherence tomography (OCT) imaging system is a high-resolution imaging device, which allows the in vivo identification of CCs accumulating within atherosclerotic plaques. The aim of this study was to investigate the relationship between the presence of CCs, other plaque morphologies assessed by OCT, and patients’ clinical characteristics including acute coronary syndrome (ACS). Methods and results Preinterventional OCT images of 173 patients with either ACS or stable angina pectoris were studied. Of 173 lesions in the patients, 66 (38%) had CCs within the culprit lesion segment and 107 (62%) had non-CC lesions. Multivariate analysis revealed that low high-density lipoprotein cholesterol levels, diabetes mellitus, the presence of plaque rupture, intimal vasculature, and thrombus were independent factors associated with CCs. Moreover, the frequency of CCs increased in proportion to the accumulation of the number of components of their vulnerable plaque features within the culprit lesion segment. Compared with the plaques without thrombus, CCs were present at shallower locations in those with thrombus. Conclusions This study demonstrates the potential correlation between the clinical metabolic disorder and vulnerable morphological features of culprit lesions to the presence of CCs in patients with stable and unstable coronary syndromes. These observations of CCs by using in vivo plaque imaging could provide incremental value to OCT evaluation of atherosclerotic plaques.

The fibrogenic response in tissue-resident fibroblasts is determined by the balance between activation and repression signals from the tissue microenvironment. While the molecular pathways by which transforming growth factor-1 (TGF-β1) activates pro-fibrogenic mechanisms have been extensively studied and are recognized critical during fibrosis development, the factors regulating TGF-β1 signaling are poorly understood. Here we show that macrophage hypoxia signaling suppresses excessive fibrosis in a heart via oncostatin-m (OSM) secretion. During cardiac remodeling, Ly6Chi monocytes/macrophages accumulate in hypoxic areas through a hypoxia-inducible factor (HIF)-1α dependent manner and suppresses cardiac fibroblast activation. As an underlying molecular mechanism, we identify OSM, part of the interleukin 6 cytokine family, as a HIF-1α target gene, which directly inhibits the TGF-β1 mediated activation of cardiac fibroblasts through extracellular signal-regulated kinase 1/2-dependent phosphorylation of the SMAD linker region. These results demonstrate that macrophage hypoxia signaling regulates fibroblast activation through OSM secretion in vivo., Fibrosis is a hallmark of several cardiac pathologies and its underlying mechanisms are still poorly defined. Here the authors show that macrophage hypoxia signaling following transverse aortic constriction in mice suppresses the activation of cardiac fibroblasts by secreting oncostatin M.

The renin-angiotensin system (RAS), which plays an important role in the progression of heart failure, is efficiently blocked by the inhibition of renin, the rate-limiting enzyme in the RAS cascade. In the present study, we investigated the cardioprotective effects of TAK-272 (SCO-272, imarikiren), a novel, orally effective direct renin inhibitor (DRI), and compared its efficacy with that of aliskiren, a DRI that is already available in the market. TAK-272 was administered to calsequestrin transgenic (CSQ-tg) heart failure mouse model that show severe symptoms and high mortality. The CSQ-tg mice treated with 300 mg/kg, the highest dose tested, of TAK-272 showed significantly reduced plasma renin activity (PRA), cardiac hypertrophy, and lung congestion. Further, TAK-272 reduced cardiomyocyte injury accompanied by an attenuation of the increase in NADPH oxidase 4 and nitric oxide synthase 3 expressions. TAK-272 also prolonged the survival of CSQ-tg mice in a dose-dependent manner (30 mg/kg: P = 0.42, 100 mg/kg: P = 0.12, 300 mg/kg: P < 0.01). Additionally, when compared at the same dose level (300 mg/kg), TAK-272 showed strong and sustained PRA inhibition and reduced the heart weight and plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration, a heart failure biomarker, while aliskiren showed a significant weaker PRA inhibition and failed to demonstrate any cardioprotective effects. Our results showed that TAK-272 is an orally active and persistent renin inhibitor, which reduced the mortality of CSQ-tg mice and conferred protection against cardiac hypertrophy and injury. Thus, TAK-272 treatment could provide a new therapeutic approach for heart failure.

Inflammation plays a key role in the pathophysiology of hepatic ischemia–reperfusion (I/R) injury. However, the mechanism by which hepatic I/R induces inflammatory responses remains unclear. Recent evidence indicates that a sterile inflammatory response triggered by I/R is mediated through a multiple-protein complex called the inflammasome. Therefore, we investigated the role of the inflammasome in hepatic I/R injury and found that hepatic I/R stimuli upregulated the inflammasome-component molecule, nucleotide-binding oligomerization domain–like receptor (NLR) family pyrin domain–containing 3 (NLRP3), but not apoptosis-associated speck–like protein containing a caspase recruitment domain (ASC). NLRP3−/− mice, but not ASC−/− and caspase-1−/− mice, had significantly less liver injury after hepatic I/R. NLRP3−/− mice showed reduced inflammatory responses, reactive oxygen species production, and apoptosis in I/R liver. Notably, infiltration of neutrophils, but not macrophages, was markedly inhibited in the I/R liver of NLRP3−/− mice. Bone marrow transplantation experiments showed that NLRP3 not only in bone marrow–derived cells, but also in non-bone marrow–derived cells contributed to liver injury after I/R. In vitro experiments revealed that keratinocyte-derived chemokine–induced activation of heterotrimeric G proteins was markedly diminished. Furthermore, NLRP3−/− neutrophils decreased keratinocyte-derived chemokine–induced concentrations of intracellular calcium elevation, Rac activation, and actin assembly formation, thereby resulting in impaired migration activity. Taken together, NLRP3 regulates chemokine-mediated functions and recruitment of neutrophils, and thereby contributes to hepatic I/R injury independently of inflammasomes. These findings identify a novel role of NLRP3 in the pathophysiology of hepatic I/R injury.

Metallothionein is a small cysteine-rich protein known to have a metal-binding function. We isolated three different lengths of rough lemon cDNAs encoding a metallothionein (RlemMT1, RlemMT2 and RlemMT3), and only RlemMT1-recombinant protein had zinc-binding activity. Appropriate concentration of zinc is an essential micronutrient for living organisms, while excess zinc is toxic. Zinc also stimulates the production of host-selective ACR-toxin for citrus leaf spot pathogen of Alternaria alternata rough lemon pathotype. Trapping of zinc by RlemMT1-recombinant protein or by a zinc-scavenging agent in the culture medium caused suppression of ACR-toxin production by the fungus. Since ACR-toxin is the disease determinant for A. alternata rough lemon pathotype, addition of RlemMT1 to the inoculum suspension led to a significant decrease in symptoms on rough lemon leaves as a result of reduced ACR-toxin production from the zinc trap around infection sites. RlemMT1-overexpression mutant of A. alternata rough lemon pathotype also produced less ACR-toxin and reduced virulence on rough lemon. This suppression was caused by an interruption of zinc absorption by cells from the trapping of the mineral by RlemMT1 and an excess supplement of ZnSO(4) restored toxin production and pathogenicity. Based on these results, we propose that zinc adsorbents including metallothionein likely can act as a plant defense factor by controlling toxin biosynthesis via inhibition of zinc absorption by the pathogen.

Acyl-CoA: cholesterol acyltransferase (ACAT) is an intracellular enzyme that catalyzes cholesterol esterification. ACAT inhibitors are expected to be potent therapeutic agents for the treatment of atherosclerosis. A series of potent ACAT inhibitors based on an (4-phenylcoumarin)acetanilide scaffold was identified. Evaluation of the structure-activity relationships of a substituent on this scaffold, with an emphasis on improving the pharmacokinetic profile led to the discovery of 2-[7-chloro-4-(3-chlorophenyl)-6-methyl-2-oxo-2H-chromen-3-yl]-N-[4-chloro-2-(trifluoromethyl)phenyl]acetamide (23), which exhibited potent ACAT inhibitory activity (IC50=12 nM) and good pharmacokinetic profile in mice. Compound 23 also showed regressive effects on atherosclerotic plaques in apolipoprotein (apo)E knock out (KO) mice at a dose of 0.3 mg/kg per os (p.o.).

Some of the steel slag from ironworks and dredged soils from marine and waterfront engineering work are partially treated as waste. However, a mixture of these two kinds of waste has the potential to be used as construction materials when mixed, due to chemical reactions forming secondary phases. Utilizing waste of such kind as a resource will help to improve sustainability in society by reducing waste and replacing virgin resources such as cement. Recently, it was reported that mixtures of steel slag and dredged soil hardens under specific conditions. The phase compositions of dredged soils and steel slags vary depending on the quantity of each component, which results in unpredictable strength development of mixtures. The effect of the variations in the components of steel slags and dredged soils on strength development of the mixtures is not yet clear, limiting the utilization of both materials. Understanding the hardening mechanisms of the mixtures will enable the prediction of strength development. Focusing on the variations in the components in steel slags and, especially of dredged soils, this study aims to identify the components in both materials that affect the secondary phase formation that are responsible for strength development. We found support for suggestions that calcium silicate hydrate, C-S-H, is one of the secondary phases responsible for the strength development of the mixtures. From a comparison of two kinds of steel slags and various dredged soils, the amount of portlandite in the steel slags and the amount of amorphous silica in the dredged soils are suggested as a couple of the key components of starting materials involved in the C-S-H formation.

To clarify the fragmentation mechanism of a molten metallic fuel jet in a sodium pool under highejection-velocityconditions that correspond to the medium- and high-burnup conditions in the metallic fuel core of liquid-metal-cooled fast breeder reactors, a series of experiments with molten copper as a metallic fuel simulant and a sodium pool was carried out. Under low-ejection-velocity conditions in the range of an ambient Weber number (Wea ) < 200, the fragmentation of the molten copper jet depends on the initial superheating of the jet. The size of copper fragments decreases with increasing initial superheating. Under high-ejection-velocity conditions in the range of Wea ≥ 200, the size of the fragments is confirmed to be almost independent of the initial superheating of the jet. Furthermore, the size of the fragments agrees well with that evaluated using the Rayleigh-Taylor instability model, in which the fragment size is assumed to be equal to half the fastest growing wavelength. This result is qualita...

Surfactant AOT (sodium bis(2-ethylhexyl)sulfosuccinate) was introduced up to 200 mmol L−1 in the aqueous Belousov–Zhabotinsky (BZ) medium. Both the induction period (IP) and the oscillation period (τ) of the BZ waves decreased significantly, whereas the wave velocity (v) increased with the concentration of AOT. These tendencies were explained in terms of the perturbations to the FKN mechanism through the uptake of Br2 and BrO 2 · into the hydrophobic core of AOT aggregates. In addition, the structures and the phase transition of AOT aggregates were suggested based on the measurement of surface tension and the correlation analysis of the IP, τ and v values.

The progression of hypothetical core disruptive accidents in metallic fuel fast breeder reactors is strongly affected by the fragmentation of molten metallic fuels due to the molten fuel-coolant interaction (FCI). As a basic study of FCI, the present paper focuses on the fragmentation of a single molten copper droplet with mass from 1 to 5 g, whichpenetrated a sodium pool at instantaneous contact interface temperatures (Ti) from 995 to 1,342°C. Intensive fragmentation of a single molten copper droplet was clearly observed even if Ti values are below the melTsing point (1,083°C) of copper besides the higher Ti range. The intensive fragmentation shows that the mass median diameters (Dm) of copper droplets with a fivefold difference in mass or the same mass have little difference, i.e., they are nearly the same. Under the lower Ti condition, the Dm data of droplet fragments of both the same and different masses scatter widely. It is found that the present Dm/D0 data of mass median diameter normalized by the ...

In order to clarify the fragmentation mechanism of a metallic alloy (U–Pu–Zr) fuel on liquid phase formed by metallurgical reactions (liquefaction temperature = 650 °C), which is important in evaluating the sequence of core disruptive accidents for metallic fuel fast reactors, a series of experiments was carried out using molten aluminum (melting point = 660 °C) and sodium mainly under the condition that the boiling of sodium does not occur. When the instantaneous contact interface temperature ( T i ) between molten aluminum drop and sodium is lower than the boiling point of sodium ( T c,bp ), the molten aluminum drop can be fragmented and the mass median diameter ( D m ) of aluminum fragments becomes small with increasing T i . When T i is roughly equivalent to or higher than T c,bp , the fragmentation of aluminum drop is promoted by thermal interaction caused by the boiling of sodium on the surface of the drop. Furthermore, even under the condition that the boiling of sodium does not occur and the solid crust is formed on the surface of the drop, it is confirmed from an analytical evaluation that the thermal fragmentation of molten aluminum drop with solid crust has a potential to be caused by the transient pressurization within the melt confined by the crust. These results indicate the possibility that the metallic alloy fuel on liquid phase formed by the metallurgical reactions can be fragmented without occurring the boiling of sodium on the surface of the melt.

Phosphatidylserine (PtdSer) exposure on the surface of activated platelets requires the action of a phospholipid scramblase(s), and serves as a scaffold for the assembly of the tenase and prothrombinase complexes involved in blood coagulation. Here, we found that the activation of mouse platelets with thrombin/collagen or Ca(2+) ionophore at 20 °C induces PtdSer exposure without compromising plasma membrane integrity. Among five transmembrane protein 16 (TMEM16) members that support Ca(2+)-dependent phospholipid scrambling, TMEM16F was the only one that showed high expression in mouse platelets. Platelets from platelet-specific TMEM16F-deficient mice exhibited defects in activation-induced PtdSer exposure and microparticle shedding, although α-granule and dense granule release remained intact. The rate of tissue factor-induced thrombin generation by TMEM16F-deficient platelets was severely reduced, whereas thrombin-induced clot retraction was unaffected. The imaging of laser-induced thrombus formation in whole animals showed that PtdSer exposure on aggregated platelets was TMEM16F-dependent in vivo. The phenotypes of the platelet-specific TMEM16F-null mice resemble those of patients with Scott syndrome, a mild bleeding disorder, indicating that these mice may provide a useful model for human Scott syndrome.

By high-speed two photon in vivo visualization system with light-manipulation technique, we visualized single cell fates, and elucidated pathological multi-cellular interplay. We applied this system for thrombus formation, artery contractions, and inflammatory responses with morphological evaluation by new software.

By improved two photon in vivo visualization, photochemical reactions, and direct laser injuries, we revealed dynamic, three-dimensional, and pathological cellular interplay. In this system, we visualized cellular processes in thrombus formation and artery contractions.

To elucidate the interdependence between the mechanical state of the myocardium and its electrical activity, previous studies have been performed at the cellular level. However, the information to date has been limited by the technical difficulties associated with stretching single myocytes.We solved this problem by combining two techniques, namely a carbon fiber technique for stretching rat myocytes with wide ranges of amplitude and speed, and ratiometric measurement of a fluorescent indicator (di8-ANEPPS) for evaluating the membrane potential in the non-contact mode.During systole, stretching caused depolarization that prolonged the action potential duration without affecting the peak amplitude, but the effect was only significant in the late phase. Application of a stretch to quiescent myocytes depolarized the membrane potential in amplitude- and speed-dependent manners, but the response was suppressed by cytochalasin D treatment, suggesting participation of the cytoskeleton in the mechanotransduction mechanism. Finally, ion replacement experiments revealed that although Na+ was the dominant charge carrier for large amplitude stretches, Ca2+ permeation was involved in small amplitude stretches, suggesting amplitude-dependent ion selectivity.Application of axial stretching to rat ventricular myocytes changed the membrane potential in phase-, amplitude- and speed-dependent manners. Amplitude may also modulate the ion selectivity of stretch-activated channels.

Adipose tissue expression and circulating concentrations of monocyte chemoattractant protein-1 (MCP-1) correlate positively with adiposity. To ascertain the roles of MCP-1 overexpression in adipose, we generated transgenic mice by utilizing the adipocyte P2 (aP2) promoter (aP2-MCP-1 mice). These mice had higher plasma MCP-1 concentrations and increased macrophage accumulation in adipose tissues, as confirmed by immunochemical, flow cytometric, and gene expression analyses. Tumor necrosis factor-alpha and interleukin-6 mRNA levels in white adipose tissue and plasma non-esterified fatty acid levels were increased in transgenic mice. aP2-MCP-1 mice showed insulin resistance, suggesting that inflammatory changes in adipose tissues may be involved in the development of insulin resistance. Insulin resistance in aP2-MCP-1 mice was confirmed by hyperinsulinemic euglycemic clamp studies showing that transgenic mice had lower rates of glucose disappearance and higher endogenous glucose production than wild-type mice. Consistent with this, insulin-induced phosphorylations of Akt were significantly decreased in both skeletal muscles and livers of aP2-MCP-1 mice. MCP-1 pretreatment of isolated skeletal muscle blunted insulin-stimulated glucose uptake, which was partially restored by treatment with the MEK inhibitor U0126, suggesting that circulating MCP-1 may contribute to insulin resistance in aP2-MCP-1 mice. We concluded that both paracrine and endocrine effects of MCP-1 may contribute to the development of insulin resistance in aP2-MCP-1 mice.

To understand the pathophysiology of hereditary cardiomyopathy, the contractile function of cardiomyopathic hamsters has been studied at the cellular level. However, most of the studies to date have described the cell shortening under the unloaded condition. Using a novel force-length measurement system for single cardiomyocytes, we studied the contractile function of cardiomyopathic hamster myocytes over a wide range of loading conditions. Cardiomyocytes were isolated from the ventricles of eight- to 10-week-old cardiomyopathic (CMP) hamsters (Bio TO-2 strain), as well as control (CTRL) Syrian hamsters. A pair of carbon fibers was attached to both ends of single cardiomyocytes and their contractile characteristics were recorded while changing the after-load by controlling the fiber motion. Under the unloaded condition, the shortening fraction (CMP 9.2+/-0.5% vs. CTRL 10.7+/-0.8%, P=0.06) and maximum shortening velocity (CMP 98.2+/-7.3 microm/s vs. CTRL 147.2+/-6.5 microm/s, P0.05) were decreased in CMP hamster myocytes. The peak force under the isometric condition (CMP 35.8+/-2.2 mN/mm2 vs. CTRL 69.0+/-8.4 mN/mm2, P0.05) and external work (CMP 898+/-130 J/m3 vs. CTRL 3058+/-576 J/m3, P0.05) under physiologically loaded conditions were also decreased, but the differences were more pronounced under the loaded conditions. Calcium transients measured by Indo-1 revealed elevated diastolic level, decreased peak level, and slower diastolic decay in CMP myocytes thus being consistent with the observed contractile dysfunction. These results clearly indicate the importance of the loading conditions in evaluating the contractile function of CMP hamster myocytes, and may provide insights into the mechanism of contractile dysfunction in this disease.

To clarify the effects of the principal factors that govern the thermal fragmentation of a molten metallic fuel jet in the course of fuel-coolant interaction, which is important in evaluating the sequence of core disruptive accidents (CDAs) for metallic fuel fast reactors, basic experiments were carried out using molten metallic fuel simulants (copper and silver) and a sodium pool.Fragmentation of a molten metal jet with a solid crust was caused by internal pressure produced by the boiling of sodium, which is locally entrapped inside the jet due to hydrodynamic motion between the jet and the coolant. The superheating and the latent heat of fusion of the jet are the principal factors governing this type of thermal fragmentation. On the other hand, the effect of the initial sodium temperature is regarded as negligible in the case of thermal conditions expected to result in CDAs for practical metallic fuel cores. Based on the fragmentation data for several kinds of jets (Cu, Ag, SUS, U, and U-5 wt% Zr alloy), an empirical correlation is proposed that is applicable to the calculation of a mass median diameter of fragments produced by the thermal fragmentation of the jet with a solid crust under low ambientmore » Weber number conditions.« less

6種類のpH指示薬（メチルオレンジ，メチルレッド，チモールブルー，フェノールレッド，フェノールフタレイン，アリザリンイエロー）を含んだそれぞれのポリビニルピロリドン膜を，メタノールや柑橘類のにおい成分にさらすとpH指示薬の色変化が観察された．スキャナーを用いて高分子膜のカラー画像を取得し，得られた画像の色情報を赤，青，緑の3成分に分けた．それぞれの成分のグレーレベルの変化量を図式化すると，それぞれのにおい成分に対して特徴的な図式が得られた．特にアリザリンイエロー含有ポリビニルピロリドン膜に対して酢酸リナリルやリナロールが大きく色変化させることが分かった．そのアリザリンイエロー含有高分子膜をクラッド部に製膜した金反射鏡付き光ファイバーをセンシング素子として用いた．光源として白色ハロゲンランプを用い，酢酸リナリルガスにさらしたとき，反射光の信号強度の減少が635 nmで観測された．固定化高分子膜の膜厚が9.00 μmの光ファイバーを測定に用いると反射光量の減少が顕著に現れた．応答変化は約20分で定常に達した．

Novel carbon structure has been prepared from heterocyclic hydrocarbons, which contain a nitrogen atom, using a fluorine expandable mica as a template. The obtained carbon particles as a residue after acid washing of carbon/mica nanocomposite comprised two structural parts: very thin film and surrounding rim part. The latter rim part has constant width of about 20 nm. In addition, on account of the nitrogen atoms in the starting hydrocarbons, a certain amount (10–18 wt.%) of nitrogen remained in the resulting template carbon. These template carbons indicated a high electric double layer capacitance amounting to more than 100–180 F/g in H 2 SO 4 electrolyte. Because of low surface area of the samples, specific capacitance per unit surface area could reach 1.2–2.2 F/m 2 , which is over 10 times as high as the capacitance of ordinary activated carbons. The capacitance decreased markedly with heat treatment temperature (>1000 °C) of the template carbon. Since the heat treatment accompanied the elimination of nitrogen from the sample, the presence of residual nitrogen may account for such a high capacitance.

To clarify the roles of Ca2+ and crossbridge kinetics in determining the cardiac contraction profile, we analyzed the rate of tension development following nitrophenyl-EGTA photolysis and the rate of relaxation following diazo-2 photolysis in the absence and presence of phosphate (Pi, 5 mM) in rat skinned ventricular trabeculae. The rate of tension development was fitted with a single exponential function. The rate constant (kc) increased not only with an increase in prephotolysis tension (initial activation level) under the same postphotolysis tension (final Ca2+ level), but also with an increase in postphotolysis tension under the same prephotolysis tension. Pi increased kc, though decreased both the prephotolysis and postphotolysis tension greatly. The rate of relaxation was fitted with a double-exponential function. The rate constants of both initial rapid phase (kr1), which was higher than kc, and subsequent slow (kr2) relaxation were almost independent of either the prephotolysis tension or the postphotolysis tension (i.e. the extent of relaxation). Pi increased both kr1 and kr2 by about twofold. These results apparently contradicting both the “steric blocking model” and the “kinetic model”, and can be explained in terms of the changes in number of tension-generating crossbridges through the Ca2+-dependent cooperative thin filament activation/inactivation associated with the Pi-modulated changes in number of tension-generating crossbridges. The thin filament activation kinetics seems to be slower than its inactivation.

The organoclay quasicrystals formed by exchange reactions of fluoromagnesian smectite (FMS) and two kinds of cationic surfactants were investigated by X-ray diffraction (XRD) of both aqueous suspensions and dried powders. ζ potential measurements were also carried out. The two cationic surfactants employed in this study, dodecyltriphenylphosphonium bromide (C12PBr) and dodecyltrimethylammonium bromide (C12NBr), have the same alkyl chain length but different head group structures. In aqueous suspensions of C12N/FMS, regular stacking with a basal spacing of 2.28 nm was observed within the range 0.4 to 1.0 of the cation exchange capacity (CEC) of the C12N/FMS ratios. The basal spacing was constant in this range. The most intense diffraction for the C12N/FMS suspension was observed at 0.6 CEC, and a further increase in the C12N/FMS ratio resulted in a decline of the diffraction intensity and a slight increase in the peak width. On the other hand, in C12P/FMS suspensions with the surfactant/FMS ratios

trans-1,2-Cyclohexanediol, the major metabolite of the cilexetil moiety of candesartan cilexetil (CC), has been reported to have potent pro-arrhythmic effects in dogs with congestive heart failure (CHF), especially when co-administered with digoxin. To verify this and to clarify the clinical relevance and the underlying mechanisms, a series of in vivo and in vitro experiments was conducted. When CC up to 300 mg/kg was administered orally to intact dogs, no changes in the electrocardiograms (ECG) or the required cumulative doses of ouabain to induce ventricular arrhythmias were observed. In dogs with CHF, intravenous bolus administration of trans-1,2-cyclohexanediol at 4 mg/kg followed by continuous infusion at 0.1 mg x kg(-)(1) x min(-)(1) had no effects on the ECG parameters, the type, incidence, and onset time of digoxin-induced arrhythmias or the metabolism of digoxin. In an in vitro experiment using isolated guinea pig papillary muscle, trans-1,2-cyclohexanediol (1 - 100 micromol/L) showed no effects on any parameter of the action potentials. Because no effects were observed in these experiments where the exposure levels of trans-1,2-cyclohexanediol were extremely high compared to those in humans given the maximum therapeutic dose of CC, it is unlikely that CC would induce arrhythmias in clinical use even in patients treated with cardiac glycosides.

Different spectroscopic and photoelectrochemical behaviors were observed when racemic and enantiomeric [Ru(bpy)3]2+ complexes were intercalated in the interlayer of K4Nb6O17, even for the same intercalation amount. The results are interpreted in terms of the stronger interaction between racemic [Ru(bpy)3]2+ molecules in the interlayer spaces of K4Nb6O17. The faster emission decay and lower photocurrent of the racemic [Ru(bpy)3]2+−K4Nb6O17 compound compared to the enantiomeric ones suggest that stronger concentration quenching exists between the racemic [Ru(bpy)3]2+ ions in the interlayer of K4Nb6O17. Combining the spectroscopic and photoelectrochemical results, the racemic [Ru(bpy)3]2+ ions are considered to intercalate more densely than the enantiomeric [Ru(bpy)3]2+ ions in the interlayer of K4Nb6O17, even for the same intercalation amount. Two cationic dyes were also directly intercalated into K4Nb6O17. The spectroscopic and photoelectrochemical behaviors of the dye−K4Nb6O17 compounds were investigated.

Sodium silicate was utilized to obtain a SiO2 coating on ZnO particles to prevent a photocatalytic reaction between ZnO and phenol. During the coating process, pH control is important to avoid dissolution of the ZnO as well as to obtain a good dispersion. Two kinds of polyelectrolyte dispersants were used to control the surface charge of the ZnO particles in aqueous media. As a result, poly(ethylenimine) (PEI) shifted the isoelectric point of ZnO from pH 9 to pH 10, whereas poly(ammonium acrylate) (PAA) made the surface charge of ZnO negative between pH 6 and pH 11. The change in the ZnO surface charge produced by adding polyelectrolyte dispersants makes it possible to obtain uniform silica–coated ZnO particle in aqueous media. UV–irradiation experiments showed that PEI, which can make the surface charge opposite to that of SiO2, is more effective in obtaining a thick silica coating on ZnO.

In order to verify the thermal fragmentation of a molten jet dropped into a sodium pool at instantaneous contact interface temperatures below its freezing point, a basic experiment was carried out using molten copper and sodium. Twenty grams of copper was melted in a crucible with an electrical heater and was dropped through a 6 mm nozzle into a sodium pool of 553 K, in the form of a jet column. Thermal fragmentation originating inside the molten copper jet with a solid crust was clearly observed in all runs. It is verified that a small quantity of sodium, which is locally entrapped inside the molten jet due to the organized motion between the molten jet and sodium, is vaporized by the sensible heat and the latent heat of molten copper, and the high internal pressure causes the molten jet with a solid crust to fragment. It is also found that the fragmentation caused in the molten copper-sodium interaction was severer than that in the molten uranium alloy jet-sodium interaction, which was reported by Gabor...

An atomic force microscope with a colloid probe technique was used to measure forces interacting between smectites, that is, saponite and hectorite. The measured forces fit well to the forces calculated by the Derjaguin-Landau -Verwey-Overbeek (DLVO) theory at separations larger than 4 nm over concentrations of 10 - 5 -10 - 2 M NaCl and the pH range of 4-10. There is also a good agreement between zeta potential and the electrical double-layer (EDL) potential extracted from the best fit to the DLVO force curve. According to the analysis on the pH dependence of the EDL potential using the Gouy-Chapman-Stern-Graham model, the inner Helmholtz layer capacitance for the good fit of the outer Helmholtz plane potential to the EDL potential required a much lower value for hectorite (∼5 μF/cm 2 ) than that for saponite (∼500 μF/cm 2 ), reflecting the difference in the location of the lattice charge between saponite and hectorite. This provided evidence for the fact that the EDL force for smectites is dominated by the location of the charges as well as the density of the charges. Extra short-range repulsion was observed at separations below ∼3 nm with increasing NaCl concentration and pH and then disappeared with decreasing pH or the NaCl concentration. The short-range repulsion was extracted as a double-exponential function, that is, F/R = A 1 exp(-D/D 1 ) + A 2 exp(-D/D 2 ), by subtracting the DLVO forces from the measured forces in the same way as the study with a surface force apparatus (Pashley, R. M. J. Colloid Interface Sci. 1981, 83, 531). The values of two decay lengths (D 1 and D 2 ) for smectites showed a very similar result to those for muscovite mica rather than silica. It was also found that the sum of the force constants (A 1 + A 2 ) was closely related to the density and structure of the lattice charge.

The characteristics of a surface plasmon resonance (SPR) sensor prepared by coating a metal film evaporated on a prism with a polymer film containing tetra-n-butyl thiuram disulfide (TBTDS) were studied. The differences in the sensitivity, selectivity, and detection limit for a Zn2+ ion of the SPR sensor were reported as a function of the thickness of the polymer film, the kind of a metal film, and the kind of a polymer film. The thinner was the polymer film, the higher was the sensitivity, and the lower was the detection limit. The Ag film gave to the SPR sensor higher sensitivity than the Au film. TBTDS contained in the poly(vinyl chloride) (PVC) film slightly improved the selectivity toward the Zn2+ ion. A non-conditioned poly(methyl methacrylate) (PMMA) film containing TBTDS gave a lower detection limit of 1.0 x 10(-6) mol/l, which is similar to that obtained by using an ion selective electrode (ISE) method, than the PVC film. The PVC film, however, gave higher concentration resolution than the PMMA film.

A surface plasmon resonance (SPR) sensor was applied to analyses of some amine compounds (n-butylamine, isobutylamine, aniline, and N,N-dimethylaniline) by using a polymer film and an acid-base reaction in it. Poly(acrylamide) (PAA) was adopted as the polymer film and was immobilized on an Au film to prepare a sensor chip. Pivalic acid was entered into the PAA film as an acid. The PAA film with a thickness of 50 nm gave the highest sensitivity to the SPR sensor. Although water was better concerning the sensitivity for the SPR sensor as the solvent, ethanol was adopted because it dissolves well all of the amine compounds used. The Au film coated with the PAA film gave higher sensitivity for analyses of n-butylamine and isobutylamine, and lower sensitivity for analyses of aniline and N,N-dimethylaniline than an Au film without the PAA film. The PAA film containing pivalic acid gave 4 - 5 orders of magnitude higher sensitivity to the SPR sensor for analyses of all the amine compounds due to the reaction between pivalic acid and these amine compounds.

Quasicrystals of synthetic fluoromagnesian smectite (FMS) in dodecyltrimethylammonium chloride (DTAC) solutions were investigated as a function of the DTAC concentration by wet type X-ray diffraction (XRD) ζ potential measurements, and dispersion and coagulation (DC) tests. The FMS had an electronegative potential and it was dispersed randomly in an aqueous suspension without DTAC. When the DTAC concentration was 0.002 mol/dm3, FMS tactoids started to develop a structure in which the layer thickness was 1.85 nm. At the isoelectric point, the DTAC concentration was 0.012 mol/dm3 and the FMS tactoid formed a regular stacked structure with a 2.25 nm layer thickness. As the ζ potential of FMS changed from negative to positive, the DC test and XRD measurement showed that the FMS association gradually changed from coagulation to dispersion, which indicates that the formation of the bilayer of surfactants on the surface of FMS produces a repulsion between DTA+ adsorbed on the silicate layer of the FMS surfaces. When the equilibrium concentration of DTAC in solution exceeded the critical micelle concentration (CMC), the ζ potential of FMS became greater than the previous values. The XRD analysis of this suspension showed that there were two kinds of rational FMS stackings; one has a layer thickness of 3.20 nm, and the other has a layer thickness of 5.45 nm due to an interstratified structure composed of 3.20 and 2.25 nm layers. The interstratified structure was confirmed by the calculated XRD profiles.

A fluorine expandable mica (EM), having two-dimensional spread in its crystal form, was used as a template for carbonization of organic liquids such as quinoline and pyridine. Despite Intrinsic volatile under the ambient pressure, these organic liquids inserted into the interlayer space of mica yielded carbonaceous compound after heat treatment over 500° C in inert atmosphere. The particle size of the compound separated from the mica layer depends on that of mica as a template. Detailed TEM observation revealed unique structure, namely each particle comprised two structural parts: film and surrounding rim part. The film part was very thin, thus being transparent for SEM observation and rim part has constant width of about 20nm. This structure is particularly interesting, because it can be carbon thin film supported by carbon micro-ring.

In order to gain the best use of filtered containment venting systems (FCVSs), the decomtamination factor of FCVSs is to be investigated as a function of system parameter including steam flow rate, pressure, temperature, water level, and operating time. A full-height test facilities were designed and constructed in Central Research Institute of Electric Power Industry (CRIEPI), Japan to evaluate the decontamination factor (DF) in FCVSs. The target types are the orifice and the venturi FCVSs. The height and the internal diameter of the cylindrical test vessel is 8 m and 0.5 m. Bubbly flows were visualized through the view window up to 0.8 MPa and 170 °C. Steam bubbles in 0.2 wt% sodium thiosulfate and 0.5 wt% sodium hydroxide were found to be much smaller than those in water. The DF were evaluated for the aerosol, elemental iodine and organic iodine. The installed aerosol optical spectrometer measures the number density and the diameter of aerosols. The concentrations of elemental iodine were quantified with an inductively-coupled plasma with mass spectrometry (ICP-MS). The concentration of organic iodine was quantified with a gas chromatography with mass spectrometry (GC-MS). In order to investigate two-phase flow dynamics in the vessel, separate effect tests were conducted with air-water test facility. The height of cylindrical test vessel is 8 m. Visual observation was conducted for two internal diameter levels: 0.05 and 0.5 m. High speed video frames were recorded through the transparent (acrylic) vessel wall. Wire-Mesh Sensors (WMS) were installed to acquire a cross-sectional void fraction to compare with DF in the facility. On the basis of the obtained database, we develop the FCVSs performance evaluation technique and propose an optimal FCVSs operation method for a further safety improvements of the nuclear power plant.

Stretch-induced arrhythmias are multi-scale phenomena in which alterations in channel activities and/or calcium handling lead to the organ level derangement of the heart rhythm. To understand how cellular mechano-electric coupling (MEC) leads to stretch-induced arrhythmias at the organ level, we developed stretching devices and optical voltage/calcium measurement techniques optimized to each cardiac level. This review introduces these experimental techniques of (1) optical voltage measurement coupled with a carbon-fiber technique for single isolated cardiomyocytes, (2) optical voltage mapping combined with motion tracking technique for myocardial tissue/whole heart preparations and (3) real-time calcium imaging coupled with a laser optical trap technique for cardiomyocytes. Following the overview of each methodology, results are presented. We conclude that individual MEC in cardiomyocytes can be heterogeneous at the ventricular level, especially when moderate amplitude mechanical stretches are applied to the heart, and that this heterogeneous MEC can evoke focal excitation that develops into re-entrant arrhythmias.

Background Paxillin is a LIM domain protein localized at integrin-mediated focal adhesions. Although paxillin is thought to modulate the functions of integrins, little is known about the contribution of paxillin to signaling pathways in platelets. Here, we studied the role of paxillin in platelet activation in vitro and in vivo. Methods and results We generated paxillin knockdown (Pxn-KD) platelets in mice by transplanting bone marrow cells transduced with a lentiviral vector carrying a short hairpin RNA sequence, and confirmed that paxillin expression was significantly reduced in platelets derived from the transduced cells. Pxn-KD platelets showed a slight increased in size and augmented integrin αIIbβ3 activation following stimulation of multiple receptors including glycoprotein VI and G protein-coupled receptors. Thromboxane A2 biosynthesis and the release of α-granules and dense granules in response to agonist stimulation were also enhanced in Pxn-KD platelets. However, Pxn-KD did not increase tyrosine phosphorylation or intracellular calcium mobilization. Intravital imaging confirmed that Pxn-KD enhanced thrombus formation in vivo. Conclusions Our findings suggest that paxillin negatively regulates several common platelet signaling pathways, resulting in the activation of integrin αIIbβ3 and release reactions.

ζ potentials of synthetic smectites with different locations of lattice charges, i.e., saponite and hectorite, were investigated as functions of pH and NaCl concentration by a flat plate streaming potential technique where two smectite-coated plates were separated by a Teflon gasket to form a slit channel. The lattice charge of saponite originates from the isomorphous substitution of Si4+ by Al3+ ions in tetrahedral silica sheets, whereas the lattice charge of hectorite is caused by the isomorphous substitution of Mg2+ by Li+ ions in octahedral magnesia sheets. The ζ potential for saponite was more sensitive to the pH of electrolyte solution than that for hectorite in acidic solution. Such a difference in pH dependence of the ζ potential could be explained by the difference in the location of the lattice charges between saponite and hectorite as a result of an analysis of the inner Helmholtz layer capacitance by using the Gouy−Chapman−Stern−Graham (GCSG) model with a single-site dissociation of surface gr...

Chirality effects have been observed in the intercalation, spectroscopic and photoelectrochemical behavior when enantiomeric and racemic [Ru(phen)3]2+ complexes were intercalated in the interlayer spaces of K4Nb6O17. The results were interpreted in terms of a [Nb6O17]4−-chelate and chelate–chelate interactions. The faster luminescence decay and higher photocurrent of the enantiomeric [Ru(phen)3]2+–K4Nb6O17 compounds than the racemic ones suggest that the emission of adsorbed [Ru(phen)3]2+ ions was not only quenched by adsorbed complexes (or concentration quenching) but also by the semiconductive host lattices.

The adsorption of dodecyltrimethylammonium bromide (DTAB) onto natural muscovite mica and a synthetic expandable mica (EM) in aqueous solution has been investigated using both microscopic and macroscopic surface characterization techniques. The electrokinetic properties of the surfaces were monitored as a function of the concentration of DTAB using atomic force microscopy and microelectrophoresis. The adsorption isotherm of DTAB on EM was measured up to a solution concentration just below the critical micelle concentration of the surfactant. The thickness of the adsorbed layer on EM was determined using X-ray diffraction. Results indicate that the adsorbed layer consists of molecules lying quite flat on the mica surface at low concentrations and adsorbed in interleaved aggregate structures at concentrations approaching the critical micelle concentration of the surfactant in solution. Copyright 2001 Academic Press.

Each transfusion requires 200-300 billion platelets in patients with thrombocytopenia. To continuously supply such a huge number of platelets by ex vivo generation, two distinct steps, megakaryopoiesis and platelet shedding, must be both considered. For the former, one approach is to increase the number of source cell, megakaryocytes. For example, the immortalized megakaryocyte cell line (imMKCL) system uses self-renewing megakaryocyte (MK) cell lines derived from induced pluripotent stem cells (iPSCs) (Nakamura et al., Cell Stem Cell, 2014). For the latter, there have been an idea of bioreactors whereby shedding of platelets from proplatelets could be promoted by flow-dependent shear force within the bone marrow in vivo (Junt et al., Science, 2007; Zhang et al., J Exp Med, 2012). Based upon this idea, we constructed a flow chamber type bioreactor recapitulating in vivo blood flow shear rate. However, this bioreactor failed to efficiently yield platelets, and moreover, the produced platelets had poor quality as indicated by high Annexin V levels (Exp Hematol, 2011 and unpublished result). Recently, we demonstrated two different kinetics of platelet biogenesis from bone marrow MKs, whereby either thrombopoietin (TPO) mostly regulates steady-state shedding of platelets from proplatelets, or interleukin-a (IL-1a) triggers inflammation-dependent rupture of MK cytoplasm contributing to a quick increase of platelet count at higher rate (Nishimura et al., J Cell Biol, 2015). However, the rupture type platelets revealed shorter half-life with relatively higher Annexin V levels. Therefore, to gain insights from platelet biogenesis in vivo, we focused on biophysical analysis of steady-state platelet biogenesis via proplatelets in bone marrow. Our observations strongly indicated that the presence of 'vorticity' defined by vortex turbulence in addition to shear-dependent 'stress' and 'strain' correlates with the efficient shedding of competent platelets. From this new finding, we developed an alternative bioreactor system, which enabled generation of 100 billion platelets from imMKCL in a 16L-scale liquid culture condition without any adherent machinery using two 10L-bioreactors. Furthermore, platelets generated via new bioreactors showed low Annexin V levels ( In conclusion, our study has uncovered the novel biophysical aspect of platelet biogenesis. The application of the new set of physical parameters in constructing large sized bioreactors shall facilitate the industrialization of platelet production. Disclosures Eto: Megakaryon Co. Ltd.: Research Funding.

A surface plasmon resonance (SPR) sensor was applied to a simple and speedy measurement of cholesterol. The lower detection limit was 5.6 × 10-4 mol/l for an ethanol solution of cholesterol. The measurable range for cholesterol almost equaled that of the concentration of cholesterol in serum without any pretreatment of the serum. There were differences between the data obtained by using a gold film and those by using an enzyme film, due to the presence of hydrogen peroxide produced by a reaction between the enzyme and cholesterol. The differences gave a linear plot in the cholesterol-concentration region of 2.0 × 10-3 to 2.0 × 10-2 mol/l, and reached a constant value in the region of 4.0 × 10-2 to 5.0 × 10-2 mol/l. The 3.0 × 10-3 mol/l ascorbic acid, which largely interfered with the spectroscopic measurement of cholesterol, did not interfere with this measurement of a 1.0 × 10-2 mol/l cholesterol/ethanol solution.

It is important to elucidate the relation between the locked cycle flotation test and the continuous flotation circuit because the locked cycled test has been traditionally the only way to experimentally simulate a continuous circuit. We analytically assessed the mass balances of the locked cycle test in a rougher–cleaner–cleaner scavenger (R–C–CS) system as a function of the iteration number of tests and provided an analytical expression of the mass balance in each separation stage. The mass of the final concentrate and flotation characteristic curves in a continuous circuit and the locked cycle test were calculated using the flotation rate constant k and flotation time T . Based on the comparison of the calculated results between the two tests, a good agreement between the locked cycle test and the continuous circuit can be obtained when the kT value for a product component with the flotation rate constant k and time T is in the range where the mass of a component does not change with kT .

Activity-guided fractionation of twigs of Pistacia chinensis resulted in the isolation and characterization of two novel ingredients as potent estrogen agonists. On the basis of spectral analysis and comparison with a related compound their structures were elucidated as 3,3''-dimers of 4-aryldihydrocoumarins (3,4-dihydro-4-(4'-hydroxyphenyl)-7-hydroxycoumarin) differing only in the stereochemical disposition of the linkage between the two 4-arylcoumarin moieties. These compounds are the first examples of bis-flavonoids which have been proven to possess estrogen-like activity.