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Background/Aims Gastric acid secretion is suspected to be a pivotal contributor to the pathogenesis of functional dyspepsia. The present study investigates the potential association of the gastric acid secretion estimated by measuring serum pepsinogen with therapeutic responsiveness to the prokinetic drug acotiamide. Methods Dyspeptic patients consulting participating clinics from October 2017 to March 2019 were prospectively enrolled in the study. The dyspeptic symptoms were classified into postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). Gastric acid secretion levels were estimated by the Helicobacter pylori infection status and serum pepsinogen using established criteria and classified into hypo-, normo-, and hyper-secretion. Each patient was then administered 100 mg acotiamide thrice daily for 4 weeks, and the response rate to the treatment was evaluated using the overall treatment efficacy scale. Results Of the 86 enrolled patients, 56 (65.1%) and 26 (30.2%) were classified into PDS and EPS, respectively. The estimated gastric acid secretion was not significantly different between PDS and EPS. The response rates were 66.0% for PDS and 73.1% for EPS, showing no significant difference. While the response rates were stable, ranging from 61.0% to 75.0% regardless of the estimated gastric acid secretion level among subjects with PDF, the rates were significantly lower in hyper-secretors than in non-hyper-secretors among subjects with EPS (42.0% vs 83.0%, P = 0.046). Conclusion Although acotiamide is effective for treating EPS as well as PDS overall, the efficacy is somewhat limited in EPS with gastric acid hyper-secretion, with gastric acid suppressants, such as proton pump inhibitors, being more suitable.

Autoignition behavior of spherical clusters of pure droplets was experimentally examined near the ignition limit. The fuel with the melting points little above room temperatures was selected as the test fuel. The three-dimensional droplet clusters having hexagonal closest packing structure were selected as the test clusters, which consisted of a center droplet and surrounding twelve droplets (thirteen droplets in total). The initial diameters of the droplets were much reduced from the authors’ previous studies. The results showed that the ignition delay of the three-dimensional droplet clusters also had a minimum at a certain droplet spacing, which has been predicted by Niioka and coworkers as a result of rate-controlling process transition between reaction and evaporation. Autoignition of the droplet clusters could be achieved for the center fine droplet, which is out of ignition limit when isolated, in combination with finer surrounding droplets.

The burning characteristics of isolated fuel droplets for ethanol, 1-butanol and n -decane were experimentally examined in carbon dioxide-rich or argon-rich environments under microgravity. The ambience consisted of oxygen, nitrogen, carbon dioxide and argon. The concentration of oxygen was fixed to be 21% in volume percentage, and that of carbon dioxide or argon was varied from 0% to 60% in volume percentage. Detailed measurements of the droplet surface areas were conducted using a high speed video camera and the effective droplet diameter squared were calculated. The instantaneous burning rates were calculated from the evolutions of the droplet diameter squared. When the soot production was limited, the instantaneous burning rate increased with time. Variations of the instantaneous burning rate with the instantaneous droplet diameter squared were obtained. The results indicated that the instantaneous burning rate was correlated with the droplet diameter squared after the initial heating period and that was approximated by the first order linear function. From the function, an indicative burning rate and the dependence of the burning rate on the droplet diameter squared were obtained. The indicative burning rate increased with increase in the argon concentration and decreased with increase in the carbon dioxide concentration. They were well related to the thermal diffusivity of the ambient gas regardless of the gas components. The existence of other factors influencing the burning rate was inferred as well. On the other hand, the dependence of the instantaneous burning rate on the droplet diameter squared was attributed to the fuel properties.

The coronary venous system is an alternate route for drug delivery to the acutely ischemic myocardium when the coronary arterial blood flow is impeded. This study was designed to determine the effect of retrograde infusion of lipid microsphere containing prostaglandin E1 (lipo-PGE1), which is believed to prevent rapid destruction of PGE1, on myocardial infarct size after acute myocardial ischemia and reperfusion. Twenty-one open-chest porcine models were subjected to 45 minutes of left anterior descending coronary artery (LAD) occlusion followed by 4 hours of reperfusion. Group A (n=7), the control group, was given, into the great cardiac vein, 4 ml of vehicle dissolved in 36 ml of saline for 5 minutes starting before the onset of reperfusion. In group B (n=7), 20 µg/4ml of lipo-PGE1 was administered into the great cardiac vein in the same manner as in group A. Group C (n=7) was treated the same as group B, but lipo-PGE1 was injected into the inferior vena caval vein. Infarct size, expressed as a percentage of area at risk, was significantly smaller in group B (56.1±12.6%) than groups A (79.4±11.4%) and C (83.0±11.1%) (p

A flame kernel initiation of methane/air combustible mixtures in the spark ignition process was investigated using a two-dimensional theoretical model including a detailed description of gas-phase chemical kinetics, shock capturing scheme and diffusive molecular transport. Interactions of chemical reactions and diffusive transports of radicals in the process of the flame kernel initiation were investigated. Although the model of plasma might be oversimplified, the qualitative behavior of OH for hydrogen/air mixture agreed well with experimental one. The influences of diffusive molecular transport and ignition energy on the flame kernel initiation were discussed. As a result, in the early stage of the flame kernel development for methane/air mixture, the hot gas expansion was dominated by a flow whichwas inducedby the blastwave and the thermal gas at the electrode gapwas self-sustainedwith anapplication of minimum ignition energy. The induction time of the flame kernel initiation strongly depended on the ignition energy and effects of preferential diffusion of lighter molecules in the early phase of the flame kernel development are outstanding especially in the case of low ignition energy near the minimum.

The burning and sooting behaviors of isolated fuel droplets for ethanol and n -decane are examined in high concentration of the ambient carbon dioxide under microgravity. A quartz fiber with the diameter of 50 μm maintains the droplet in the center of the combustion chamber and the range in the initial droplet diameter is from 0.30 to 0.80 mm. The ambience consists of oxygen, nitrogen and carbon dioxide. The concentration of oxygen is 21% in volume, and that of carbon dioxide is varied from 0% to 60% in volume. Detail measurements of the projected image of the droplet are conducted by using a high speed video camera and the effective droplet diameter squared are calculated from the surface area of the rotating body of the projected object. From evolutions of the droplet diameter squared, the instantaneous burning rates are calculated. Time history of the instantaneous burning rate clearly represents the droplet combustion events, such as the initial thermal expansion, ignition and following combustion. The instantaneous burning rate for n-decane shows an increasing trend during combustion, while that for non-sooting ethanol remains almost constant or shows a decreasing trend. A slight stepwise increase in the instantaneous burning rate is observed for larger n -decane droplets in air, which may be attributed to soot accumulation. However, this behavior of the burning rate disappears in higher concentration of carbon dioxide. Direct observation of the droplet flame indicates suppression of soot production in higher concentration of carbon dioxide and the suppression is enhanced for smaller droplet.

An experimental study has been made of the combustion and evaporation of miscible binary fuels on a heated surface at elevated pressures. Photographic observation was made for elucidating how the binary fuel droplets or films behaved on the heated surface and for obtaining the characteristic lifetime as a function of the surface temperature, the ambient pressure and the initial concentration of highly volatile component of the fuels. The binary fuels tested were mixtures of n-hexane and n-decane. The results showed that the lifetime curve both for the combustion and for the evaporation of n-hexane/n-decane on the heated surface had two peaks at lower pressures, the first peak in the film-type evaporation region and the second peak in the spheroid-type evaporation region. The preferential evaporation of the highly volatile component was responsible for the appearance of the first peak in the film-type evaporation region. The second peak corresponded to Leidenfrost point. The increase in the ambient pressure caused a shift of the lifetime curve toward higher surface temperature and a decrease in the lifetime at two peaks. The lifetime curve decreased monotonically with increasing the surface temperature and the spheroid-type evaporation was not observed at higher pressures. The increase in the initial concentration of highly volatile component caused a shift of the first peak toward higher surface temperature, a decrease in its lifetime and a slight shift of the second peak toward lower surface temperature. The combustion caused a remarkable decrease in the lifetimes around the first peak and in the spheroid-type evaporation region and a slight increase in the surface temperature at the first peak, while the surface temperature at the second peak remained almost unchanged.

A numerical analysis with a detail description of flow dynamics and chemical kinetics on the effect of the equivalence ratio of methane/air mixtures on the minimum ignition energy is carried out. In the early stage, the behavior of the flame kernel is dominated by a flow which is induced by the blast wave. Although a high temperature gas, which spurts out from the electrode gap, quenches, the gas at the electrode gap is self-sustained with an application of small ignition energy near the minimum. After a certain period of time, the flame kernel gradually grows out of the electrode gap. In the case of high-energy application, hot gas region, which spurts out from the electrode gap, doesn't quenches and propagatable flame kernel is formed at the early stage of spark ignition process. The local equivalence ratio at the electrode gap is larger than that in the outer region with an application of small energy although its effect is not so strong in an application of high energy. In addition, calculated profile of the minimum ignition energy as a function of the equivalence ratio for methane-air mixtures shows a minimum value below the equialence ratio of 1.0. An effect of preferential diffusion for lighter molecules is confirmed.

Autoignition and early flame behavior of a spherical cluster of 49 monodispersed droplets in a high-temperature air were examined in microgravity. The monodispersed suspended-droplet cluster (MSDC) model with which both droplet spacing and initial droplet diameter were well-controlled was developed, and the solidified-fuel fiber-suspension technique was utilized for making the MSDC model. The tested 3D MSDC models had the HCP (hexagonal closest packing) structure. Individual flames, which enveloped each droplet, or group flame, which enveloped the whole droplet cluster, were formed immediately after ignition. The flame changed from the group flame to a cluster of the individual flames either with increasing the droplet spacing or decreasing the initial droplet diameter. Each of the individual flames merged into the group flame with the lapse of time. Burning sphere diameter decreased at the beginning, and then increased. The transition from the individual flames to the group flame occurred around the time period at which the burning sphere diameter reached its minimum. The time period at which the burning sphere diameter reached its maximum was delayed and the expansion rate of the burning sphere was enhanced with decreasing the droplet spacing or with increasing the initial droplet diameter.

An experimental study has been made of the microexplosion of an emulsion droplet on a hot surface during Leidenfrost burning. Photographic observation is used to study how the emulsion droplet behaves and what happens inside the droplet and to measure the waiting time for the onset of microexplosion. Weibull analysis was used to obtain the distribution function of the waiting time for the onset of microexplosion and to derive the formula for the rate of microexplosion as a function of water volume and emulsion temperature. The base fuels employed were n-decane, n-dodecane, n-tetradecane, and n-hexadecane. The results show that the increase in emulsion temperature with lapse of time results in the agglomeration and coalescence of microdroplets of base fuel dispersed in the continuous phase of water inside the emulsion droplet, terminated by the complete separation of the two phases. At the end of the phase separation process, an opaque water droplet is formed in the central core and is enveloped by the transparent shell of base fuel. Preferential evaporation of the base fuel occurs after the phase separation. The volume of the base fuel decreases while the water volume remains constant. The onset of the microexplosion of an emulsion droplet burning on the hot surface is classified by the wearout type of the Weibull distribution. The waiting time for the onset of the microexplosion decreases with increases in the normal boiling point of base fuel, initial water content, ambient pressure, and test surface temperature. The rate of microexplosion increases with the lapse of time and with increased normal boiling point of the base fuel. The rate of microexplosion increases linearly with increasing water volume in the emulsion droplet and decreases exponentially with the inverse of emulsion temperature.

Gabexate mesilate, a synthetic protease inhibitor, is used to treat acute pancreatitis and disseminated intravascular coagulation because it inhibits various serine proteases; however, whether gabexate mesilate prevents acute liver failure has not yet been studied. The aim of the present study was to investigate the effect of gabexate mesilate in carbon tetrachloride (CCl4)-induced liver injury in rats.Acute hepatic failure was induced by administration of CCl4 intragastrically to male Sprague-Dawley rats. The effects of gabexate mesilate were examined in terms of serum transaminase levels, liver histology, and the prognosis of rats.Gabexate mesilate treatment significantly decreased the elevation of serum transaminase levels and improved liver histology 24 h after the administration of CCl4 (0.2 ml/100 g rat weight). Plasma tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) decreased significantly in the gabexate mesilate-treated rats compared with saline-treated rats. Gabexate mesilate treatment also significantly improved survival rate after a lethal dose of CCl4 (0.5 ml/100 g rat weight) from 0% to 20%.Gabexate mesilate treatment attenuated CCl4-induced liver injury via a suppression of proinflammatory cytokine production. In addition, these investigations suggest that gabexate mesilate treatment may provide therapeutic strategies for human acute liver failure.

An experimental study has been carried out to reveal the statistical characteristics for the onset of micro-explosion of an emulsion droplet burning on a hot surface. Detail measurements of the waiting time for the onset of micro-explosion are made for various properties of base fuel, water contents and surface temperatures. The Weibull analysis is applied to obtain the distribution function of the waiting time for the onset of micro-explosion and to derive the empirical formula for the rate of micro-explosion as a function of water volume and emulsion temperature. The base fuels employed are n-decane, n-dodecane, n-tetradecane and n-hexadecane. The results show that the waiting time is correlated well with the Weibull distribution of the wear-out type. The mean waiting time decreases with an increase in the boiling point of base fuel, water content and surface temperature. An empirical formula is proposed for the rate of micro-explosion as a function of water volume and emulsion temperature.

Background and Aim: A 70-kDa heat shock protein (stress-inducible HSP70, HSP72) has been reported to be a cytoprotectant in a variety of organs. It has been reported that HSP72 protected non-cirrhotic rats against endotoxemia. However, its cytoprotective effect against endotoxemia in cirrhotic rats has not yet been studied. In this study, we investigated the cytoprotective effect of HSP72 on lipopolysaccharide (LPS)-induced liver injury in carbon tetrachloride (CCl4)-induced cirrhotic rats. Methods: Liver cirrhosis was produced by an 8-week intraperitoneal injection of CCl4 in male Sprague–Dawley rats. Expression of HSP72 was investigated using western blot analysis. Cirrhotic rats were given an intraperitoneal injection of LPS (10 mg/kg) with or without hyperthermia (42.5°C, 15 min) preconditioning. Liver injury was assessed biochemically (aspartate transaminase, alanine transaminase, bilirubin, lactate dehydrogenase, creatinine) and histologically. The plasma tumor necrosis factor (TNF)-α level was determined. Results: Hyperthermia preconditioning induced a 4-fold increase in HSP72 in the cirrhotic rat liver. Pre-induction of HSP72 prevented LPS-induced liver injury, as evaluated using serum biochemical parameters and histology with reduced TNF-α response. Conclusion: These findings suggest that pre-induction of HSP72 may provide therapeutic strategies for Gram-negative sepsis-induced liver injury in liver cirrhosis.

An experimental study was performed to clarify the flame structure of a burning fuel droplet. Both OH and soot concentration distributions were measured along diametrical line passing through the center of fuel droplet and the front stagnation point of a fuel droplet flame in steady air stream.The laser induced fluorescence and the laser light scattering techniques were applied for the measurement of OH and soot concentration distributions, respectively. An Nd : YAG laser-pumped pulsed dye laser emitting monochromatic radiation at a wavelength of 283.56 nm was used as the light source for these measurements. Fuel employed were n-heptane, n-hexadecane, benzen, methanol and their mixtures. The results showed that the highly sooting region was located deep inside the flame front, and near the flame front was located the maximum of OH concentration. An increase in the relative humidity in the air stream caused the decrease of OH concentration.

Cardiopulmonary bypass (CPB) surgeries cause an increase in plasma inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) along with whole-body inflammatory responses. The inflammatory responses during a CPB treatment are reduced when using a heparin-coated extracorporeal circuit. Because many cytokines, growth factors, and complements are known to interact with heparin, the reduction of inflammatory responses by a heparin-coated circuit is likely to depend on this heparin-binding nature of the inflammatory cytokines. In this study, the inflammatory cytokines, TNF-alpha and IL-6, in fetal bovine serum (FBS) bound to a heparin-agarose beads (heparin beads)-column and the adsorptions were competitively inhibited on addition of heparin in a concentration-dependent manner. TNF-alpha in FBS required a higher concentration of heparin (50% concentration inhibition [IC50] > 20microg/ml) to inhibit adsorption to the heparin beads-column compared with IL-6, probably because of a stronger interaction between TNF-alpha and heparin-beads. TNF-alpha and IL-6 concentrations in human heparinized blood significantly increased after a CPB treatment. Although the adsorbed amount of IL-6 onto the heparin-coated circuit was low (less than 6% of free circulating IL-6), a significant amount of TNF-alpha adsorbed onto the circuit (23.9-755% of free circulating TNF-alpha). Therefore, the adsorption of inflammatory cytokines, especially TNF-alpha, onto the inner heparin-coated surface of an extracorporeal circuit may partly account for a reduction in inflammatory responses.

The present study aims to establish a new experimental methodology (Fine Wire Sustaining method, FWS) and to obtain the fundamental data of spray combustion, the combustion of the liquid fuel droplets cloud. To simulate the fuel droplet cloud, each droplet was suspended at points of intersection of fibers. The geometrically controlled droplets arrayed in two or three dimensions imitated the liquid fuel droplet cloud. The experiments were performed to investigate the flame shape and the ignition delay of the droplet cloud in high temperature. The influences of the surrounding droplets on the flame shape and on the ignition delay of the center droplet were investigated. The droplet distance was the experimental parameters. As a result of the experiments, the combustion characteristic of the droplet cloud could be investigated by using the new experimental methodology. The flame shape of the fuel droplet cloud could be classified by using the group combustion number G. The ignition delay of the center droplets arrayed in three dimensions decreased with the droplet distance to the extent that the flames are isolated.

An experimental study was performed to obtain the detailed information needed to provide a deep understanding of the combustion process and the secondary atomization of an oil-in-water emulsion droplet. The experiments were conducted by using the drop shaft of JAMIC (Japan Microgravity Center) at Hokkaido. The oil-in-water emulsion, which consisted of n -hexadecane as a base fuel, distilled water, and a trace of surfactant was tested. Photographic observation and temperature measurements were made of the suspended emulsion droplet during the heating-up and combustion processes under microgravity. The primary attention was toward the phase separation in the droplet, and the time histories of droplet temperature and the amount of water in the droplet, during the period of time prior to disruptive microexplosion. The results showed that the separation of the base fuel and water as well as their agglomeration and coalescence occurred with the lapse of time. The increase in the droplet temperature resulted in phase separation, and the formation of a single water droplet enveloped by a shell of the base fuel, prior to the microexplosion. The volumes of the base fuel and the water in the droplet were estimated from the obtained droplet images. After the phase separation, selective evaporation of the base fuel occurred and the volume of the base fuel decreased, while the water volume did not change. The effects of the emulsion properties on the onset rate of microexplosion were also revealed by using statistical analysis.

An experimental study was made of the ignition process of single droplets of binary mixtures subjected to a laminar flat flame propagating through a lean homogeneous propane/air mixture at constant pressure. Binary fuels consisting of n -hexane and n -hexadecane or n -dodecane, and benzene and n -hexadecane were tested. Water-emulsified liquids consisting of n -dodecane, and pure fuels like n -hexane, n -octane, n -dodecane, and n -hexadecane, were used as well. A combustion chamber made of a transparent duct was installed with spark electrodes, fine quartz fibers to suspend fuel droplets, and a shutter to allow the burned gas to escape at the top end. A high-speed video camera was provided for photographic observation of each droplet ignited by the propagating flame. The ignition delay of pure fuel droplets increased monotonically with increase of the initial droplet diameter and decrease of fuel volatility. The influence of the initial droplet diameter on the ignition delay decreased with increasing fuel volatility. Ignition delay of the binary fuel droplets decreased with an increase of the volume concentration of the higher-volatility fuel. Ignition delay of the binary fuels showed a minimum and a maximum as a function of the initial droplet diameter. The diameters at the minimum and the maximum of ignition delay decreased with increasing higher-volatility fuel concentration. For the emulsified fuel, on the other hand, ignition delay increased with increasing initial droplet diameter and increasing water content. Part of the propagating flame behind the droplet became convex toward the unburned gas as it passed a droplet of higher-volatility fuels, while the flame remained flat for the lower-volatility fuels. The deformation length of the propagating flame behind the droplet increased with increasing higher-volatility fuel concentration.

For the final goal of developing the natural gas-fueled spark-ignition engines with high thermal efficiency and low pollutant emission, the effects of the fluid flow inside a combustion chamber on the combustion process of a homogeneous lean methane/air mixture were examined using a rapid compression combustor. The rapid compression combustor was designed to simulate the combustion process in a spark-ignition engine involving the rapid compression of a mixture and the heat release during the flame propagation. The main advantage of using this combustor is that experiments can be made under the idealized and well-controlled conditions. The time history of pressure in the combustion chamber was measured with a pressure transducer. The fluid flow in the combustion chamber was varied as follows; the mixture was injected into the combustion cylinder before the compression stroke, and the direction of the injection and the time interval between the end of mixture charge and the start of compression stroke were varied. The position of spark ignition was also varied. And the flame propagation was photographically observed. Moreover, the two-dimensional velocity distribution of the swirl flow was measured with particle image velocimetry. As expected, the combustion duration decreased with increases in the mean velocity and the turbulence intensity of the fluid flow. When the intense swirl flow existed in the combustion chamber, the combustion duration was minimized with spark ignition at the eccentric location.

An experimental study has been performed under microgravity conditions to obtain the detailed information needed to understand the combustion phenomena of a fuel droplet which autoignites in supercritical gaseous environment. A fuel droplet suspended at the tip of a fine quartz fiber in the cold section of the high-pressure combustion chamber was transferred quickly to be subjected to a hot gas in an electric furnace. This resulted in the evaporation, autoignition, and combustion of the fuel droplet in a supercritical gaseous environment. A high-speed video camera was provided to observe thebehavior of the fuel droplet and the droplet flame. In the present study, primary attention was focused on the ignition delay and the flame diameter at the initial stage of droplet burning. 1-Octadecanol and n-octadecane were selected as the test fuels. Mixtures of oxygen and carbon dioxide and of oxygen and nitrogen were used as the ambient gas. The ambient pressure was extended up to pressures around two times the critical pressure of the fuels tested. The ignition delay was found to have a minimum around the ambient pressure equal to the critical pressure of the fuel, and a maximum in the range from 1.5 to 2 times the critical pressure. Higher oxygen concentration of the ambient gas caused shorter ignition delay at ambient pressures equal to or above 1.5 times the critical pressure. Higher ambient pressure caused a smaller droplet flame at the onset of autoignition and higher flame growth rate and a larger flame diameter afterward. The flame diameter decreased with an increase in the oxygen concentration of the ambient gas.

International audience; A Franco-Japanese cooperative research program on microgravity combustion has been initiated. One of the studies is devoted to the experimental investigation of high pressure combustion of methanol droplets, under normal and reduced gravity conditions, which are obtained in a drop tower and during the parabolic flight of an airplane. A methanol droplet is suspended at the center of a high-pressure combustion chamber, and is ignited with an electrically heated kanthal wire. A high-speed video camera is used to obtain the time histories of the squared droplet diameter, which are used to determine the droplet burning rate. The results show that the d-square law is valid for all the conditions of the present experiments. The droplet burning rate increases with ambient pressure and does not show a maximum around the critical pressure of methanol. Experiments also show that the droplet burning rate decreases with the reduction of gravitational acceleration.

Objective: The objective of this study was to investigate the protective effects of nitric oxide synthase inhibitor, N g -nitro-l-arginine methyl ester hydrochloride, on reperfusion injury of the brain under hypothermic circulatory arrest. Methods: After cardiopulmonary bypass was established using 12 piglets each weighing about 30 kg, the animals were cooled to a brain temperature of 20° C and circulatory arrest was performed for 90 minutes followed by reperfusion for 120 minutes. The level of nitric oxide within the brain was measured with a needle electrode inserted into the brain. In the treatment group, N g -nitro-l-arginine methyl ester hydrochloride was administered with an intravenous injection of 1.5 mg/kg at the onset of the reperfusion followed by a 60-minute continuous venous infusion of 1.5 mg/kg/hr. Results: In the control group, nitric oxide levels within the brain increased not during ischemia but during reperfusion, and the level after 120 minutes of reperfusion increased significantly compared with that of before circulatory arrest. But in the treatment group, N g -nitro-l-arginine methyl ester hydrochloride administered at the onset of reperfusion inhibited nitric oxide production during reperfusion. A significant difference was observed between the groups regarding the nitric oxide level after 120 minutes of reperfusion. Regarding cerebral blood flow, excess lactate, and cerebral tissue water content, no significant difference was observed between the groups. However, recovery of somatosensory evoked potential after 120 minutes of reperfusion was detected in all six animals in the treatment group, but none in the control group ( p = 0.001). Conclusion: These data suggest that N g -nitro-l-arginine methyl ester hydrochloride protects the brain against reperfusion injury under hypothermic circulatory arrest. (J Thorac Cardiovasc Surg 1998;115:925-30)

The present study was carried out to reveal the possibility of controlling the ignition delay of hydrogen-air mixtures by applying electric fields. A quiescent stoichiometric hydrogen-air mixture was ignited by a suddenly heated thin wire of nickel or tungsten. DC electric fields were applied between the wire and outer electrode plates parallel with the wire. The mean ignition delay was calculated stochastically from the measured ignition delays which scattered considerably. Both with the nickel wire and with the tungsten wire, positive voltages applied to the outer electrode plates resulted in almost the same change of the mean ignition delay ; The mean ignition delay showed a slight increase at the lower applied voltages, while it became very short at the highest applied voltages. When the nickel wire was used and negative voltages were applied, the mean ignition delay decreased even at the lower voltages. However, it showed little change with the tungsten wire and the negative applied voltages.

Microgravity combustion experiments have been carried out for an emulsion droplet suspended at a quartz fiber by free-fall method. Attention was mainly paid to the effect of gravity on the occurrence of microexplosion that may be caused by the bubble nucleation at temperatures below the superheat limit. The oil-in-water emulsion consisted of the base fuel and water was employed after degasification. The base fuel employed was n -dodecane and n -tetradecane. The water content was 0.2 in volume. The waiting time for the onset of microexplosion was measured for about 30 runs under normal gravity and microgravity. The onset probability of microexplosion was discussed from the statistical point of view by using the weakest link destruction model. The results showed that the distribution function of the waiting time correlated with the mixed Weibull distribution for both gravity conditions. That is, the distribution function is classified to the wear-out type at the initial heating period, and it is classified to the chance failure type at constanttemperature period. The change in the type of Weibull distribution occurs slightly earlier under normal gravity than microgravity for both base fuels. The Weibull distribution of the waiting time at constant-temperature period for normal gravity is almost the same as that for microgravity. The dependence of the onset rate of microexplosion on the superheating of water is independent of the gravity condition.

The present study was carried out to reveal the possibility of controlling the ignition delay of combustible mixtures by applying electric fields. A thin nickel wire was used as a hot surface to ignite the mixtures. It was suddenly heated up and then its temperature was kept constant. Quiescent propane-air mixtures were used as combustible mixtures. DC electric fields were applied between the nickel wire and the outer electrode plates parallel with the nickel wire. As the applied voltage to the electrode plates increased, both the mean values and the fluctuations of the ignition delay decreased regardless of the electric polarities. Without electric fields, both the mean ignition delay and the fluctuation varied with the equivalence ratio of the mixture. With increasing the applied voltage up to =2kV, the variations became to disappear. When the surface temperature was low, the stoichiometric mixture could be ignited only by applying the electric fields.

An experimental study has been made of the evaporation, autoignition, and combustion of a fuel droplet in supercritical gaseous environments for the deep understanding of the combustion processes in gas turbine, diesel engine, and rocket motor in which the operating pressure often exceeds the critical pressure of the liquid fuel of frequent utilization. The parabolic flight of aircraft provided the long period of time for the experiments that allowed observation of the processes during the entire lifetime of a fairly large droplet from the start of evaporation to the end of burning in quiescent supercritical gaseous environments under microgravity. A fuel droplet suspended at the tip of a fine quartz fiber in the cold section of the high-pressure combustion chamber was translated quickly to be subjected to a hot gas in an electric furnace. This resulted in the evaporation, autoignition, and combustion of the fuel droplet in supercritical gaseous environments. A video camera was provided to observe the behavior of the fuel droplet as well as the flame around the droplet. The fuel tested is octadecanol, which solidifies at 331 K and the critical conditions of which are 1.4 MPa and 747 K. The experiments were done in the quiescent gaseous environments at low oxygen concentration to reduce the soot produced in the flame and to make it possible to observe the backlighted image of the droplet during its entire lifetime. The ignition delay, the burning time, and the lifetime of the droplet showed minima at the ambient pressure approximately equal to the critical pressure of the liquid fuel. The burning rate constant that was determined from the time histories of the droplet diameter showed a peak at the ambient pressure 1.5 times as high as the critical pressure of the liquid fuel.

Low sodium chloride-containing soy sauce samples were prepared by adding salty peptide and its related compounds to pre-soy sauce. The soy sauce obtained by adding Orn-Tau·HCI was very similar to commercial soy sauce in that it exhibited unadulterated saltiness and a good relative balance between salty and umami tastes. The soy sauce obtained by adding Gly-OEt·HCI exhibited a slightly stronger salty taste, while the one obtained by adding Lys·HCI had a slightly weaker salty taste at high concentrations than commercial soy sauce. The soy sauce obtained with added KCI produced a stronger umami taste at all concentrations than the commercial type. The influence of ingredients other than NaCI and MSG in soy sauce (amino acids, acids, sugars, and alcohol) on the salty and umami tastes of soy sauce was also studied. In comparison with the NaCI substituents studied here, these compounds were not as effective for influencing the apparent intensity of the taste of soy sauce when they were individually added.

Two-dimensional visualization of the soot concentration profile in a flame formed around a suspended droplet was carried out under microgravity conditions using the planar laser light scattering technique. The 500-in drop shaft in Japan was used for microgravity experiments, which offers the effective time of the microgravity of 10 s and the relatively large space of the falling assembly for constructing the optical measurement system. The soot concentration and the instantaneous amount of soot were estimated approximately from the intensity of the scattered light using the image analysis system. The fuels employed were water-in-oil emulsions composed of base fuel, water, and surfactant. The base fuel was n -dodecane. The sooting region can be observed spherically around the droplet by using the apparatus developed in the present work. The results showed the unsteadiness of the sooting behavior and the flame behavior. Most of the soot concentration is located in the vicinity of the inner edge of the sooting region, which corresponds to the soot shell observed previously. The maximum of soot concentration does not vary with the water content, whereas the maximum amount of soot decreases significantly with water emulsification.

A new convenient synthesis of a salty peptide, ornithyltaurine (Orn-Tau), was designed. Compared with a conventional synthesis, the process was shortened by two steps and the purification was made much easier in the new one. Consequently, Orn-Tau was easily obtained and subjected to a further series of experiments. The product produced a good saltiness without Na+ in the presence of HCl, and the saltiness became stronger as the amount of added HCl increased. The best quality of saltiness was obtained by adding 1.2 equiv of HCl to the Orn-Tau solutions. The Orn-Tau·1.2HCl was equally salty to NaCl on a molar basis and also had an enhancing effect on saltiness of NaCl. The intake of Na+ could be cut by 95% in a model system and by 50% in a food material (soy sauce) by using Orn-Tau·1.2HCl, which have the most excellent saltiness and Na+ dietary effect of our NaCl substitutes at the present time. Keywords: Salt substitute; l-ornithyltaurine; sodium ion dietary effect; new large scale synthesis

To establish the usefulness of amino acid based saltiness enhancers, soy sauce containing a basic amino acid, glycine ethyl ester hydrochloride, or taurine was prepared. The enhancer-added soy sauce produced the same level of saltiness as that of normal soy sauce, although it contained only 4.6% NaCI. Taste quality of these samples was superior to that of low sodium chloride containing soy sauces that contain conventional saltiness enhancers, such as KCl, MgCl2, MnCl2, and others.

Mao is one component of various traditional herbal medicines. We examined the effects of Mao on an acute liver failure model treated with d-galactosamine (GalN) and lipopolysaccharide (LPS). The lethality of mice administrated Mao with GalN/LPS was significantly decreased compared with that in mice without Mao. Hepatic apoptosis and inflammatory cell infiltration were slight in Mao-treated mice. Serum alanine aminotransferase (ALT) and total bilirubin (T.Bil) activity, tumor necrosis factor alpha (TNF-alpha) levels and caspase 8, 9, and 3 activity in the liver were significantly lower in mice administrated Mao. But, Serum interleukin-6 (IL-6), IL-10 levels and signal transducers and activators of transcription 3 (STAT3) activity in the liver were significantly higher in mice administrated Mao. To investigate the effect of STAT3, we used AG490, which selectively inhibits the activation of Janus kinase (JAK) family tyrosine kinase and inhibits the constitutive activation of STAT3. There was significant aggravation in hepatic apoptosis treated with Mao and AG490 compared with Mao alone. In conclusions, Mao significantly suppressed hepatic apoptosis by inhibition of TNF-alpha production and caspase activity. Furthermore, it is also suggested that Mao, which activates STAT3 induced by IL-6, may be a useful therapeutic tool for fulminant hepatic failure.

Background and Aim: Epimorphin, a morphoregulatory factor essential to organ development, is believed to direct normal morphogenesis in tissue repair. We examined the dynamics and the roles of epimorphin, a cell surface-associated molecule detected on mesenchymal cells, in hepatic tissue repair from acute liver injury. Methods: After acute liver injury was induced by carbon tetrachloride in Balb/c mice, the distribution of epimorphin-expressing cells was studied immunohistochemically. To clarify interactions between epimorphin expression and hepatocyte behavior, epimorphin-expressing cells and proliferating hepatocytes were counted. Then, epimorphin quantity and isoforms were assessed by western blotting. To better understand effects of epimorphin, we cultured rat hepatocytes in its presence. Results: Epimorphin was distributed in relation to sinusoids, portal veins, central veins and granulomas, expressed in stellate cells and myofibroblasts. In the periportal zone, the expression in sinusoids was decreased at 24 h but increased on day 7 after carbon tetrachloride administration. Numbers of epimorphin-expressing cells and proliferating hepatocytes changed in an inverse manner as time progressed. In the pericentral zone, reactivity for epimorphin was markedly enhanced concurrently with appearance of granulomas. Quantities of 34-kDa isoform paralleled epimorphin-staining intensity. In vitro, epimorphin induced spherical hepatocyte aggregates and maintained differentiated hepatocyte function. Conclusions: Epimorphin is involved in tissue repair following a single injection of carbon tetrachloride, in which distribution and the quantity of epimorphin expression are important, particularly in maintaining hepatocyte function. © 2005 Blackwell Publishing Asia Pty Ltd

Aim Suramin is a symmetrical polysulfonated naphthylamine derivative of urea. There have been few studies on the effect of suramin on cytokines. We examined the effects of suramin on production of inflammatory cytokines. Methods We made an acute liver injury model treated with d -galactosamine (GalN) and lipopolysaccharide (LPS). Plasma AST, ALT, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 levels were measured. We compared with survival rate, histological found and NF-κB activity between with and without treatment of suramin. In macrophage like cell line, TNF-α and IL-6 production, TNF-α and IL-6 mRNA expression, and NF-κB activity was measured. Results The lethality of mice administered suramin with GalN/LPS was significantly decreased compared with that in mice without suramin. Changes of hepatic necrosis and apoptosis were slight in suramin-treated mice. Serum AST, ALT, TNF-α, IL-6 levels and NF-κB activity in the liver were significantly lower in mice administered suramin. In an in vitro model, suramin preincubation inhibited TNF-α and IL-6 production, TNF-α and IL-6 mRNA expression, and NF-κB activity. Conclusions Suramin inhibits TNF-α and IL-6 production through the suppression of NF-κB activity from macrophages and shows therapeutic effects on acute liver damage.

Genipin is a metabolite derived from the herbal medicine Inchinko-to. Little is known about the mechanism of genipin action on acute liver injury through inflammatory cytokines. We examined the effects of genipin on production of TNF-alpha in vivo and in vitro. Mice were given GalN/LPS with or without genipin treatment. All mice not given genipin died within 12h. But in mice given genipin, 8 of 15 mice survived for 24h after GalN/LPS administration. Histologically, hepatic necrosis and inflammatory cells infiltration were significantly slight in mice given genipin. Serum AST and ALT activity were significantly lower in mice given genipin. Serum and liver homogenate TNF-alpha levels were significantly lower in mice given genipin. However, in IL-6 and IL-1beta, there were no significant differences in mice given and not given genipin. TNF-alpha, NF-kappaB activation and TNF-alpha mRNA expression in a cultured mouse macrophage-like cell line J774.1 were significantly suppressed by genipin administration. In conclusion, the present findings suggest that genipin, a metabolite derived form the herbal medicine Inchinko-to improved acute liver dysfunction by suppressive effect of TNF-alpha production.

Previous studies have shown moderate or severe phlebitis at the site of venipuncture in some patients who receiving prostaglandin E1 (PGE1) infusion therapy. Such phlebitis is sometimes severe enough to necessitate the cessation of PGE1 therapy. This study investigated how to continue PGE1 infusion therapy for 3 weeks with tolerable phlebitis. Although a 60 μg dose of PGE1 is usually dissolved in 500 mL of fluid to avoid phlebitis, we used 200 mL to prevent volume overload. This PGE1 solution was neutralized to pH 7.4 with 4 mL of 7% sodium bicarbonate. We examined the frequency and severity of phlebitis among patients who received a 2-h PGE1 infusion twice daily. Eighteen patients who were hospitalized for peripheral vascular disease between June 1998 and May 1999 were studied. All of them were men and their mean age was 63.3 ±8.9 years (range: 47-78 years). Fourteen patients had arteriosclerosis obliterans and four had Buerger's disease. When the severity of phlebitis was determined according to Dinley's criteria, two patients (11%) had grade 0, four patients (22%) had grade 1, eleven patients (61%) had grade 2, and one patient (6%) had grade 3 phlebitis. Usually, PGE1 infusion therapy is stopped when phlebitis reaches grade 4 or more, but there were no such cases in this study. We also found that aging was significantly correlated with a decrease in the severity of phlebitis (Spearman's rank correlation test: r = -0.545, p = 0.0193).

Excessive intake of NaCl is implicated in hypertension, toxemia of pregnancy, and other diseases in adults. Soy sauce, the most representative seasoning in Japan, contains a high concentration of NaCl, on average, 16%. We have studied salty substances that can be substituted for NaCl and have successfully developed some saltiness-enhancing substances [1]: Orn-β-Ala, Gly-OEt · HCl, Lys · HC1, and Orn · HCl. In 1991, Muramatsu et al. [2] succeeded in improving the soy sauce manufacturing process, decreasing the NaC1 concentration to a maximum of 4.59%. We designated this preparation, pre-soy sauce. Using this as the starting material, and adding the saltiness-enhancing substances, Gly-OEt · HCl, Lys · HCl, and KC1, we designed the experimental manufacture of a new low-salt soy sauce Amino acid derivatives are relatively easy to use in practice in terms of metabolic safety and economic efficiency in the manufacturing process, and this metal chloride has long been known as a salty substance. The preparations thus obtained were compared with commercial soy sauce to determine the most desirable manufacturing conditions for the production of low-salt soy sauce.

The perfect enantioselective catalysis was obtained for the hydrolytic cleavage of p-nitrophenyl N-dodecanoyl-D(L)-phenylalaninates through the modified enzyme (Decanoyl-α-Chymotrypsin).