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Changes in climate and anthropogenic pressures might affect the composition and abundance of forage fish in the world's oceans. The junk‐food hypothesis posits that dietary shifts that affect the quality (e.g., energy content) of food available to marine predators may impact their physiological state and consequently affect their fitness. Previously, we experimentally validated that deposition of the adrenocortical hormone, corticosterone, in feathers is a sensitive measure of nutritional stress in seabirds. Here, we use this method to examine how changes in diet composition and prey quality affect the nutritional status of free‐living rhinoceros auklets (Cerorhinca monocerata). Our study sites included the following: Teuri Is. Japan, Middleton Is. central Gulf of Alaska, and St. Lazaria Is. Southeast Alaska. In 2012 and 2013, we collected “bill loads” delivered by parents to feed their chicks (n = 758) to document dietary changes. We deployed time–depth–temperature recorders on breeding adults (n = 47) to evaluate whether changes in prey coincided with changes in foraging behavior. We measured concentrations of corticosterone in fledgling (n = 71) and adult breeders' (n = 82) feathers to determine how birds were affected by foraging conditions. We found that seasonal changes in diet composition occurred on each colony, adults dove deeper and engaged in longer foraging bouts when capturing larger prey and that chicks had higher concentrations of corticosterone in their feathers when adults brought back smaller and/or lower energy prey. Corticosterone levels in feathers of fledglings (grown during the breeding season) and those in feathers of adult breeders (grown during the postbreeding season) were positively correlated, indicating possible carryover effects. These results suggest that seabirds might experience increased levels of nutritional stress associated with moderate dietary changes and that physiological responses to changes in prey composition should be considered when evaluating the effect of prey quality on marine predators.

Mixed cationic Ca2+/Na+(Mg2+) polyphosphates, regarded as potential biocomposite fillers, were fabricated by solid-state reactions. Most of them demonstrated low solubility (assessed also by the Glasser and Jenkins approach) from 1 ± 0.2 g/L for Ca(PO3)2 to 5 ± 0.4 g/L for NaCa(PO3)3 and 50 ± 2 g/L for soluble phase of NaPO3. Liquid-state NMR of the soluble part of polyphosphates gave the degree of polymerization of their chains ranging from 10 to 30 for NaCa(PO3)3 and ca. 1000 monomeric units for NaPO3.

Mullite (3Al2O3•2SiO2) undergoes a phase transition at 30 GPa with forming aligned nanocrystalline fragments in an amorphous phase. The direction of the crystal axes of mullite nanocrystals with the grain sizes less than 10 nm is that preserved from the starting specimen. To clarify the mechanism of the nanofragmentation in mullite, compositional and structural effects are investigated by comparative studies using several mullite-related aluminosilicates. Consequently, we proposed that the oxygen vacancies in the crystal structure in mullite play an important role to formation of the nanofragmentation textures. Also, we performed impact experiments using mullite as a bumper material, simulating a Whipple bumper shield for spacecrafts. Damage of impact could be considerably less with mullite bumper shield than with aluminum alloy bumper shield, suggesting that mullite could be an candidate for a Whipple bumper materials in the next generation.

In this study, field electron emission current uniformity and stability of the well-aligned carbon nanotubes (CNTs) synthesized in methanol has been investigated by using the scanning probe field emission current (SPFEC) measurement system. The effect of crystallinity of the well-aligned CNT is also discussed.

We have developed high performance silver sheathed Bi2223 wire. The progress in three years is especially remarkable. This dramatic development has been made with the controlled overpressure (CT-OP) sintering technique. The CT-OP sintering technique improves not only the critical current but also other performances such as n-value and mechanical strength, because of the improvement of the relative density up to almost 100%, the homogenization of the Bi2223 phase and the stronger connectivity between the Bi2223 grains. The dense Bi2223 wire prevents the ballooning phenomenon which is caused by the gasification of the trapped liquid nitrogen during warming up to room temperature. Present critical current has reached as about twice high as that in those days and shows over 200 A (77 K, self-field), which showed an excellent critical current property in a magnetic field.

Silver-sheathed Bi-2223 multi-filamentary tapes using controlled-overpressure sintering have attained the highest critical current of 200 A-class at 77 K, self field. The 200 A-class Bi-2223 tape has been evaluated on the critical currents at various temperatures from 4.2 K to 90 K and magnetic fields up to 12 T applied perpendicularly to the tape plane. The critical currents are 500 A at 4.2 K, 5 T, 370 A at 20 K, 3 T and 200 A at 20 K, 10 T typically. This is an improvement by a factor of 1.3-1.5 compared to current commercial tapes produced using controlled-overpressure sintering.

Titanium diboride (TiB2) has excellent mechanical properties, and is expected to be used as crashworthy material. In this study, the Hugoniot-measurements were performed on the TiB2 polycrystal by means of the inclined-mirror method combined with the powder gun and two-stage gas gun to study the elastoplastic transition and to search phase transition. The Hugoniot-elastic limit (HEL) stress was measured to be approximately 12 GPa. The shock velocity (US) vs. particle velocity (UP) relation of the final phase was given by U S = 8.79 + 0.78 U P km / s in the plastic region of 0.6–3.0 km/s in particle velocity. The shock velocities were much large compared with the bulk sound velocity, and those in 0.24–0.6 km/s were further larger than the linear Hugoniot relation. This result showed that this material preserved the large shear strength also in the plastic region. No phase transition was observed up to 120 GPa.

We studied the influence of the high isostatic pressure and critical current density in Bi2223 long length wires. Heat treatments of Bi2223 wire were carried out using controlled over-pressure sintering process. The controlled over-pressure sintering process allows Bi2223 wires to have higher Ic by more than 30%, because the process increase the relative density up to almost 100% resulting in higher phase purity, higher grain alignment and better grain connectivity than those made with a conventional normal pressure sintering process. Densification of the Bi2223 wire prevents liquid nitrogen penetration during long term exposure to liquid nitrogen of it for use in power cable applications. The ballooning, which the trapped nitrogen expands and forms after Bi2223 wire was warmed to room temperature, does not occur in the controlled over-pressure sintering processed wire. These high performance levels in long length Bi2223 wires have enabled commercial level products and projects such as power cables, magnets and many others.

In situ observation experiments of semiconductor solution growth using a near-infrared microscope have been performed to investigate an influence of surface orientation of a substrate crystal upon the morphological change of the S/L interface. The orientation dependence of step kinetic coefficient at the interface in GaP/GaP growth was obtained under a reduced convection condition in order to evaluate a behavior of macrosteps during the growth. A morphological change of S/L interface at the early stage of GaAs x P 1-x /GaP hetero-LPE growth was also discussed from the view point of the surface orientation dependence.

For the purpose of quick screening for charge transfer (CT) transitions of Yb 3+ in various hosts, (Lu 1-x Yb x ) 3 Al 5 O 12 (Yb:LuAG) with x = 0.05, 0.15, 0.30 and (Y 1-x Yb x )AlO 3 (Yb:YAP) with x = 0.05, 0.10, 0.30 were grown by the micro-pulling-down method. (Y,Yb)VO 4 with strong wetting was grown by edge defined film-fed growth method and materials, which require moderate temperature gradient, such as Ca 8 (La,Yb) 2 (PO 4 ) 6 O 2 and (Gd,Yb) 2 SiO 5 were grown by Czochralski method. Strong dependence of the CT luminescence decay time and intensity on temperature was observed for Yb-doped LuAG and YAP. Super fast decay with 0.85 ns decay time was observed in Yb(30%) doped YAP at room temperature. Though the emission intensity is weak at room temperature, it exceeds several times that of PbWO 4 . In addition, CT luminescence of Yb:YAP occurs at longer wavelength than in BaF 2 , which enables the usage of glass-based photomultiplier for the detection. In addition, higher stopping power will be expected due to the higher density host compared with BaF 2 .

(Bi, Pb)2Sr2Ca2Cu3OX (Bi2223) superconducting wires (Tc∼110 K) is a promising candidate of high-Tc superconducting wire which can be expected for practical use. We have proceeded with its research of Ag-sheathed wire using Bi2223 superconductor and has developed semi-mass producing long wires (in the kilometer class) with high Jc. And for application, magnet, power transformer and power cable have been developed. At present we improve the performance of Bi2223 wires and have proceeded with cable project in the real scale.But it is still necessary for practical use to improve the performance of Bi2223 wires. In this paper, we concentrated on the sintering process and applied controlled over pressure sintering method. The sintering process has a problem which the mass density increased on rolling process decreases during sintering. Since decreased density causes the formation of pores and a decrease of supercurrent between Bi2223 grains which grow during sintering, it is considered to be one of the major causes of the performance of Bi2223 wires. Controlled over pressure sintering is a method which applies gas pressure to Bi2223 wires during sintering because of suppression of decreasing mass density.As the results of short samples, controlled over pressure sintering method improved Bi2223 phase homogeneity, misalignment angle, connectivity, critical current density and mechanical property. Furthermore, when cooled in liquid nitrogen and warmed up to room temperature, the wires may often balloon up by vaporization of liquid nitrogen entered in the pores of filaments through the defects of the sheath. However controlled over pressure sintering removes pores in filaments and it is confirmed that wires were not ballooned after cooled in liquid nitrogen under 1 MPa for 24H so far.To apply controlled over pressure sintering to long length Bi2223 wires, we developed the large furnace which kilometer-scaled Bi2223 wires can be sintered. The performance of long length wires is almost equal to that of short samples.

In-depth distribution of rusts on two weathering steels and a plain carbon steel exposed to atmosphere for 17 years under a bridge at a coastal + industrial region in Japan were studied. In the rust layer on all specimens, α-FeOOH, β-FeOOH, γ-FeOOH, Fe3O4 and so-called amorphous rust were found. Within rust layers, there were thick parts and thin parts, which were finely and complicatedly distributed on steels. Among these rust species, α-FeOOH was dominant on all specimens. α-FeOOH appeared almost homogeneously through the rust layer. Its concentration was higher on weathering steels than on plain carbon steel. β-FeOOH was found mainly at thick parts and was scarce at thin parts of rust layers. Concentration of α-FeOOH was higher and that of γ-FeOOH was lower on weathering steels than on plain carbon steel. Amorphous rust was located at the bottom of the rust layer irrespective of steel types. Concentration of magnetite was negatively correlated with concentration of β-FeOOH.

抗牛インヒビンαサブユニット抗体を用いた時間分解蛍光免疫測定法を用いて正常雌牛のLHサージから排卵後約24時間までの血中インヒビンαサブユニット濃度の変化を測定した。その結果、3例について排卵確認後にインヒビン濃度が十数時間にわたって上昇する傾向が見られ、4例については排卵しても特に一定の傾向を示さなかった。これは排卵によって卵胞液中のインヒビンが血中に吸収されるためであると考えられる。

Behavior of point defects under thermal stress in growing Czochralski (CZ) silicon is theoretically examined. The changes in point defect concentration by the thermal stress depending on the growth rate are quantitatively estimated, and their contributions to the formation of secondary defects are discussed.

Secondary electron (SE) intensity was measured in situ during Ga supply on the molecular beam epitaxy (MBE) grown GaAs (0 0 1) surface using scanning electron microsope-MBE hybrid system. SE intensity changed in the opposite way to the reported work function change and the correspondence was excellent. This is promising for in situ, nondestructive determination of local work function during MBE growth or nanometer device process in vacuum.

Recovery of bacterial cells from radiation damage and the effects of microgravity were examined in an STS-79 Shuttle/Mir Mission-4 experiment using the extremely radioresistant bacterium Deinococcus radiodurans. The cells were irradiated with gamma rays before the space flight and incubated on board the Space-Shuttle. The survival of the wild type cells incubated in space increased compared with the ground controls, suggesting that the recovery of this bacterium from radiation damage was enhanced under microgravity. No difference was observed for the survival of radiosensitive mutant rec30 cells whether incubated in space or on the ground. The amount of DNA-repair related RecA protein induced under microgravity was similar to those of ground controls, however, induction of PprA protein, the product of a newly found gene related to the DNA repair mechanism of D. radiodurans, was enhanced under microgravity compared with ground controls.

Behavior of point defects under the internal stress in a growing Czochralski (CZ) silicon is theoretically examined. The changes of point defect concentration by the impurity doping and by the thermal stress are quantitatively estimated. Contributions of them to the formation of secondary defects are discussed.

We prepared Ag-sheathed mono-core tapes and multifilamentary tapes with 19 filaments by the powder-in-tube method, using V- and Ir-doped Bi2223 powder with a doping amount x less than 0.15. In the doped tapes two effects are overlapped: One is the decrease in J/sub c/ due to some weak links caused by precipitates such as Sr-V-O oxides, and the other is the increase in J/sub c/ with the doping content due to the enhancement of Bi2223 phase formation. This results in a minimum in J/sub c/ at x=0.05. The second effect becomes stronger in the V-doping, because of the great enhancement of Bi2223 phase formation. In the Ir-doped tapes the J/sub c/ values decrease monotonically with the doping content. For the multifilamentary tapes the V-doping is very effective to obtain high I/sub c/ values.

The growth of c-GaN epitaxial films on GaAs substrates in the afterglow plasma region controlled by magnetic field was investigated using ECR plasma MOCVD. Measurement of plasma parameters such as electron temperature, plasma space potential and floating potential in the mirror and cusp magnetic fields in growth chamber was carried out. Dependence of the crystallinity and crystal orientation of c-GaN on the magnetic field in the afterglow plasma region was investigated. The relationship between the crystallinity of c-GaN and the plasma parameters was considered.

A new hemoglobin (Hb) variant, Hb Sagami [β139(H 17)Asn→Thr] was accidentally found through the assay of Hb A1c by high performance liquid chromatography (HPLC) in a screening test for diabetes mellitus (1). The amino acid substitution was determined by electrospray ionization mass spectrometry (ESI/MS) and confirmed by an automatic protein sequencer (1). The content of the abnormal β chain was about twice that of normal β chain, which was estimated by ESI/MS with intact globin mixture, and by high-resolution ion exchange column chromatography (PolyCAT A; Poly LC, Columbia, MD, USA) with Hb.

Fifty fresh isolates of Trypanosoma cruzi from Triatoma dimidiata vectors and 31 from patients with Chagas disease were analysed for DNA polymorphisms within the 432-bp core region of the cruzipain gene which encodes the active site of cathepsin L-like cystein proteinase. The cruzipain gene showed signs of polymorphism consisting of four different DNA sequences in Central and South American isolates of T. cruzi . The PCR fragments of Guatemalan isolates could be divided into three groups, Groups 1, 2 and 3, based on different patterns of single-stranded DNA conformation polymorphism. All of the strains isolated from Brazil, Chile, and Paraguay, except for the CL strain, showed a Group 4 pattern. Two to four isolates from each group were analysed by cloning and sequencing. A silent mutation occurred between Groups 1 and 2, and five nucleotides and two aa substitutions were detected between Groups 1 and 3. The DNA sequence of Group 4 contained five nucleotides and one aa substitution from Group 1. All of the DNA sequences corresponded well with the single-stranded DNA conformation polymorphism. The Group 1 isolates, the majority in the Guatemalan population (70/81, 86.4%), were isolated from both triatomines and humans, but Group 3 were isolated only from humans. Moreover, the Group 2 isolates were detected only in triatomine vectors (9/50; 18%), but never in humans (0/32, P

Ultraviolet laser light of sufficient power can induce focal œdema in the brain. The formation of ultraviolet-induced vasogenic \kdema was monitored by observing real-time changes in the integrity of the blood–brain barrier. The brain surface of guinea-pigs injected with Evans blue was exposed to light from a continuous wave argon laser at 351 nm, delivered via an optical fibre. The integrity of the blood–brain barrier was evaluated by measuring surface reflectance using a separate probing light. The brain was then sectioned and examined using light and electron microscopy. Extravasation of Evans blue following vasodilatation was observed when the irradiation intensity was greater than 0.64 W/cm2. The extent of glial and vascular damage could be correlated with the laser power. Irradiated vascular endothelium exhibited lipping at the tight junction, vacuolation and mitichondrial swelling. These results suggest that disruption of the blood–brain barrier induced by ultraviolet light is preceded by vasodilatation.

The ductile fracture tests are carried out using compact type (CT) specimen, three point bend specimen and center cracked tension (CCT) specimens made of A533B steel and aluminum alloy with different crack lengths. The effect of the crack tip constraint on the microscopic fracture behavior is studied by the scanning electron microscope (SEM). It is shown that the apparent J IC . value increases due to the decrease of the crack tip constraint. It is pointed out that the increase of the apparent J IC . value is partly due to the error of the conventional equation to estimate the J value. Based on the FEM analyses, these apparent J IC . values are corrected and are compared with the valid J IC . values. The good co-relation between apparent J IC . value and the Q factor, proposed by O'Dowd and Shih, is shown for all the specimens. The FEM analyses based on the Gurson's constitutive equation is also carried out. The effect of the constraint on the crack tip field is discussed.

The corrosion behavior of an amorphous Zr40Cu60 alloy in laboratory air (RH = 60 ± 10%) at room temperature was studied by grazing incidence X-ray diffraction (GIXRD) and Auger electron spectroscopy (AES) combined with Ar ion sputter-etching. In general, the corrosion behavior of the roll-side of the specimen which was in contact with the chilling roll during quenching was different from that of the freely solidified surface (top-side). The GIXRD data suggested that monoclinic ZrO2 (m-ZrO2) and tetragonal ZrO2 (t-ZrO2) were formed under a surface layer of metallic copper which was also formed by corrosion of alloy. The t-ZrO2 was distributed more deeply than the m-ZrO2. By AES, it was clarified that a metallic copper layer covered with a very thin ZrO2 was placed in the topmost region, and that, under the copper layer on the roll-side surface, a sandwich structure of ZrO2 and metallic copper was formed, i.e. the corroded region consisted of several layers of ZrO2-rich and copper-rich layers distributed alternatively. On the top side, however, the oxidized layer did not develop significantly and the sandwiched structure of ZrO2 and metallic copper was not observed.

The relative contributions of inflammatory mediators to the increase in vascular permeability in antigen-induced pleurisy were examined in rats actively sensitized with ovalbumin. The effects of various inhibitors were assessed on the exudate volume and plasma exudation rate in the pleural cavity. Two peaks were observed in plasma exudation rate at 0.5 and 3 h after antigen challenge. At 0.5 h, there was a marked decrease in the histamine content of the pleural cells and also a sharp increase in the LTE4 level in the exudate, which was inhibited dose-dependently by the lipoxygenase inhibitor T-0757. Indomethacin and cyproheptadine both depressed exudate volume and exudation rate, whereas T-0757 only reduced the exudation rate. At 3 h, a substantial LTE4 concentration was still detected in the exudate, and the exudation rate was depressed by T-0757 and indomethacin, but not by cyproheptadine. These results suggest that histamine is involved mainly in the early phase, and leukotrienes predominantly contribute to the later phase of exudation. Prostaglandins appear to be involved in both phases. Allergic pleurisy of rats, therefore, may be a suitable model to examine the roles of these inflammatory mediators.

An experimental and numrical investigation of ignition and the subsequent transition to flame spread over a thermally thin cellulosic sample is described. The experiments were conducted using a lamp as an external radiant source in a 50% oxygen atmosphere at three diffeirent wind velocities of 0.2, and 5 cm/s in a 10 s drop tower. The results show that there are no significants effects of the slow wind on the ignition-delay time. Photographic sequences of both the experiments and the calculations show that the wind increases the flame propagation speed in the upwind direction. while decreasing it in the downstream direction. The downstream clame fails the transition to flame spread and becomes a tail of the upstream flame. The downstream char front propagates much slower than that for the upstream direction. Three-dimensional, time-dependent numerical solutions to the Navier-Stokes equations are used to simulate the experiments. Three global degradation reactions describe the pyrolysis of the sample paper, and one gasphase reaction describes the combustion of the fuel gases. The model results reflect the qualitative features of the experiments and also are in reasonable quantitative agreement, give the uncertainty of the gasphase reaction mechanism.

Lipoprotein-a, Lp(a), is a variant form of low density lipoprotein (LDL) that contains apolipoprotein-a, whose structure has 75-85% homology with plasminogen. Elevated plasma levels of Lp(a) are considered to be one of the independent risk factors for cardiovascular disease. We studied the effects of niceritrol, a nicotinic acid derivative, on plasma Lp(a) levels in 72 patients with hypercholesterolaemia. The dose of niceritrol was increased every 4 weeks, from 750 to 1500 and then to 2250 mg day-1. The final dose was adjusted to obtain a plasma cholesterol level less than 5.69 mmol l-1. Niceritrol led to significant decreases in plasma levels of median Lp(a), from 16.1 mg dl-1 (interquartile intervals, 8.7 to 32.8) to 11.1 mg dl-1 (interquartile intervals, 6.6 to 21), the mean reduction rate being 17.6%. In the group with pretreatment Lp(a) levels of over 20 mg dl-1, Lp(a) decreased by 10.0, 22.0 and 31.8% at the doses of 750, 1500, and 2250 mg day-1, respectively. In the group with levels less than 20 mg dl-1, only the dose of 2250 mg day-1 was effective in the reduction of Lp(a). The results suggest that the reduction of Lp(a) was dependent on the dose of niceritrol and on the pretreatment level of Lp(a). In conclusion, niceritrol is effective, in a dose-dependent manner, for reducing Lp(a) levels.

We measured continuum x-rays from an aluminium target bombarded with 60 keV- and 80 keV- proton beams. On the basis of the PWBA theory, we calculated the thick target yields of atomic bremsstrahlung and nuclear bremsstrahlung produced in very low energy ion-atom collisions and compared with the experiment. The present theory predicts that the main component of continuum x-rays produced in such low energy ion-atom collisions is the nuclear bremsstrahlung. The theory presents the yields of continuum x-rays about 5 times larger than the experimental ones, however, reproduces well the spectral shape.

In order to improve the anode characteristics of pitch-based carbon fibres for Li secondary batteries, we adopted two kinds of heat treatment procedures, i.e. in vacuo and in a partially oxidizing atmosphere. Heating to 980°C in vacuo was found to remove the surface hydroxyls and adsorbed water effectively. This method improved the high current charge-discharge capacities and cyclability of the carbon fibres.

A transcutaneous lactate monitoring method has been developed by combining a suction effusion fluid (SEF) collecting technique with a micro-planar amperometric biosensor. SEF is directly collected by a weak suction through the skin from which the stratum corneum has been removed. A micro-planar biosensor, has also been developed for determining lactate concentrations in very small samples. The biosensor utilizes a lactate oxidase immobilized membrane on a micro planar platinum electrode to yield a lactate sensor. The sensor is based on amperometric detection of hydrogen peroxide generated by the lactate oxidase-catalyzed oxidation of l -lactate. The linearity of the lactate sensor response was obtained from 0.5 mM to 25 mM and the response time was about 10 s. The sensor was applied to the SEF lactate measurement of a rabbit during induced high lactate levels. Lactate concentrations measured with SEF showed good correlation with those obtained directly from whole blood. This result suggests the feasibility of transcutaneous lactate monitoring without the use of blood sampling.

Protein disulfide isomerase (PDI) and the DsbA/PpfA protein catalyze the oxidation of mutant human lysozyme, L79CC81A, which has two native disulfide bonds, Cys6-Cys128 and Cys30-Cys116, a non-native Cys79-Cys95, and 2 free cysteine residues at positions 65 and 77. Oxidation of L79CC81A (R-form) yielded two isomers, L79CC81A-a (A-form) with tandem-linked Cys65-Cys77 and Cys79-Cys95, and L79CC81A-b (B-form) with cross-linked Cys65-Cys79 and Cys77-Cys95 (Kanaya, E., Ishihara, K., Tsunasawa, S., Nokihara, K., and Kikuchi, M. (1993) Biochem. J. 292, 469-476). PDI mainly enhanced the formation of the A- form in the absence of oxidized glutathione (GSSG); however, as the concentration of GSSG increased, it markedly accelerated the formation of the B-form. In contrast, the DspA/PpfA protein mainly enhanced the formation of the A-form, regardless of the presence or absence of GSSG. These results and the presumed spatial locations of Cys65, Cys77, and Cys79-Cys95 in the R-form suggest that 1 of the half-cystine residues in the active site of PDI and the DsbA/PpfA protein can react with 1 of the 2 free Cys residues of the R-form. The dependence on GSSG of the B-form formation with PDI can be explained by the formation of two transient intermolecular disulfide bonds between PDI and the R-form and the attack of GSSG by the resultant thiolate anion of Cys79 or Cys95. The independence of the reaction with the DsbA/PpfA protein from GSSG can be explained by the formation of one transient intermolecular disulfide bond. The possible formation of the two transient intermolecular disulfide bonds involving two sulfur atoms of PDI and 2 cysteine or half-cystine residues of the substrate could explain the high isomerase activity of PDI.

Insulin secretion from pancreatic islets is controlled by peptides as well as by nutrients. We report here a novel, extraordinarily potent peptidergic regulation of insulin secretion. A 27-residue form of pituitary adenylate cyclase activating polypeptide (PACAP27) as low as 10(-14) to 10(-13) M stimulated insulin release from rat islets in a glucose-dependent manner. PACAP27 also increased cytosolic free Ca2+ concentration ([Ca2+]i) in islet beta-cells. Nitrendipine, a blocker of the L-type Ca2+ channel, abolished both [Ca2+]i and insulin responses. Vasoactive intestinal peptide, a peptide exhibiting 68% amino acid homology with PACAP, also increased [Ca2+]i in beta-cells but only at concentrations in the nanomolar range, indicating that PACAP27 is 4 logs more potent. A 38-residue form of the peptide (PACAP38) stimulated insulin release and increased beta-cell [Ca2+]i in a manner similar to that of PACAP27. PACAP-like immunoreactivity was demonstrated in pancreatic nerve fibers, islets, and capillaries. The results indicate that PACAP is a physiologically occurring peptide in pancreas and that PACAP, in a glucose-dependent manner, activates beta-cells presumably via a high affinity PACAP-selective receptor, raises [Ca2+]i by increasing the activity of L-type Ca2+ channels, and consequently stimulates insulin release. PACAP appears to be by far the most potent insulinotropic peptide known.

Lysozyme has two distinct folding domains, and in most molecules the alpha-helical domain folds more quickly than the beta-sheet domain in vitro [Radford, Dobson and Evans (1992) Nature (London) 358, 302-307]. In order to investigate the relationship between the formation of disulphide bonds and protein folding in vivo, we carried out cysteine scanning mutagenesis to shift positions of the disulphide bonds in both the alpha-helical and beta-sheet domains of human lysozyme. Of the constructed mutants (nine in the beta-sheet domain and 13 in the alpha-helical domain), the mutant L79CC81A, in which Leu-79 and Cys-81 in the beta-sheet domain were replaced by Cys and Ala respectively, was secreted by yeast. The rest of the mutants were retained in the insoluble fraction of the cell, probably because of a failure of folding. The distance between the two alpha-carbons at positions 79 and 95 in the wild-type protein is too far to form a disulphide bond, but analysis of the primary structure revealed that the major part of L79CC81A was secreted with a non-native disulphide bond Cys79-Cys95 and two free cysteine residues at positions 65 and 77 in the beta-sheet domain. These results suggest that the beta-sheet domain of human lysozyme can tolerate the shift of locations of disulphide bonds, and the non-native folding of mutated polypeptide chains in in vivo folding. The free residues Cys-65 and Cys-77 formed a disulphide bond in vitro by air oxidation, yielding two isomers. On the basis of our previous results and present study it is suggested that the formation of Cys6-Cys128 is the first step of the in vivo correct folding of human lysozyme, and disulphide bonds in the beta-sheet domain are post-translationally formed in vivo.

Background and Study Aims: Endoscopic variceal ligation (EVL) is an alternative to sclerotherapy for the treatment of esophageal varices, but is associated with higher rates of recurrence and subsequent bleeding than sclerotherapy. To prevent recurrence of varices after EVL, we have developed a low-dose diode laser therapy combined with the injection of indocyanine green, which allows enhanced tissue absorption of the laser beam selectively around varices. In this study we investigated the efficacy and safety of this technique. Patients and Methods: Eight patients with F2 or F3 esophageal varices were enrolled. At 1 week after EVL, indocyanine green solution (1 mg/ml) was injected sub-mucosally around the remaining varices. A diode laser (power 10 watts) was applied to the surface from the esophagogastric junction to 5 cm above it. The spot size was kept to 5 mm in diameter. Results: Laser irradiation was performed safely, without bleeding from the varices, or perforation. There were no major complications. Endoscopy 1 month later showed F0 forms in seven patients, F1 in one patient, and no red color sign in any patient. No recurrence of varices has been observed in any of the patients during the follow-up period of at least 12 months. Conclusion: This technique may provide a simple, safe and effective procedure, as an additional treatment to EVL, for the prevention of recurrence of esophageal varices.

The Bi-based oxide superconducting wire is one of the most promising materials for practical uses such as electric power transmission, electromagnets and so on. For the higher performances required in these applications, it is necessary to increase the critical current (Ic). We have carried out synchrotron radiation X-ray diffraction analysis to improve our manufacturing processes and thus to achieve higher Ic. We have performed in situ X-ray diffraction measurements during the sintering and cooling processes, and observed the decrease of Bi-2223(=(Bi,Pb)2Sr2Ca2Cu3Ox) phase during the cooling process. We have also evaluated the distribution of the crystal orientation in whole wire thickness, by measuring the rocking curves. We have observed that the distribution of the crystal orientation is improved by a refinement of the process conditions.

The aim of this study was to evaluate the use of vacuum-impregnation (VI) for enriching the ascorbic acid content of whole potatoes. Whole potatoes were immersed in a 10% ascorbic acid (AA) solution. A vacuum pressure of 70 cm Hg was applied for 0–60 min, following atmospheric pressure restoration for 3 h, while samples remained in the VI solution. AA concentrations of potatoes were measured using HPLC. The effects of cooking and storage time in subsets of the fortified samples were also evaluated. Results indicated that the AA concentration of whole potatoes increased with vacuum time (max 150 mg/100 g fr. wt.). In addition, a steam-cooking study showed that 100 g of the 25 min steam-cooked VI potatoes could provide adults with 90–100% of the recommended daily allowance of AA (100 mg). The storage study showed that VI whole potatoes had a relatively high AA concentration (50 mg/100 g fr. wt.), even at 14 days of storage at 4 °C. This study indicated that VI treatment of whole potatoes was useful for enriching the AA content.

The mutant h-lysozyme, W64CC65A, with Trp64 and Cys65 replaced by Cys and Ala, respectively, was secreted by yeast and purified. Peptide mapping confirmed that W64CC65A contained a nonnative Cys64-Cys81 bond and three native disulfide bonds. The mutant had 2% of the lytic activity of the wild-type lysozyme. The midpoint concentration of the guanidine hydrochloride denaturation curve, the [D]1/2, was 2.7 M for W64CC65A at pH 3.0 and 25 degrees C, whereas the [D]1/2 for the wild-type h-lysozyme was 2.9 M. These results show that the W64CC65A protein is a compactly folded molecule. Our previous results, using the mutant C81A, indicate that Cys81 is not required for correct folding and activity, whereas Cys65 is indispensable (Taniyama, Y., Yamamoto, Y., Kuroki, R., and Kikuchi, M. (1990) J. Biol. Chem. 65, 7570-7575). Cys64 substituted for Cys65 in W64CC65A, even though the distance between the alpha-carbons at positions 64 and 81 in the wild-type h-lysozyme is not favorable for forming a disulfide bond. Unlike C81A, the mutant W64CC65/81A, which has the additional substitution of Ala for Cys81, did not fold. These results suggest that the absence of both the Cys64-Cys81 bond and the amino acid residue Trp64 caused the misfolding or destabilization of W64CC65/81A in vivo. It is proposed that the formation of the alternative bond, Cys64-Cys81 is important for the folding of W64CC65A in vivo.

Some studies have demonstrated the benefit of blood glucose control as close as possible to physiological conditions. Not enough reports have investigated in detail the 24-h plasma profiles of insulin/glucose/C-peptide. Here we investigated the 24-h plasma profiles of physiological insulin/glucose/C-peptide in healthy Japanese adults.In order to evaluate the 24-h profiles of physiological insulin/glucose/C-peptide profiles, 42 blood samples were taken from each subject in our group of healthy Japanese volunteers to measure the 24-h profile with three standardized meals.Plasma glucose and insulin increased rapidly followed by a rapid decrease after each meal with little variation at night. The average peak values of insulin after each meal were as follows: 426.20 pmol/L (breakfast), 373.75 pmol/L (lunch), and 410.28 pmol/L (dinner). The average times to peak insulin were 0.651 h (breakfast), 0.677 h (lunch), and 0.689 h (dinner). The corresponding average maximum postprandial plasma glucose levels were 8.39 mmol/L (breakfast), 8.77 mmol/L (lunch), and 8.74 mmol/L (dinner). The average times to peak glucose were 0.738 h (breakfast), 0.650 h (lunch), and 0.625 h (dinner). The average maximum postprandial C-peptide levels were 2.64 nmol/L (breakfast), 2.55 nmol/L (lunch), and 2.67 nmol/L (dinner). No major differences were found in these parameters between the Caucasian and Japanese populations.This is the first investigation to measure the 24-h profiles of insulin/glucose/C-peptide in healthy Japanese volunteers with standardized meals. It is hoped this information will provide useful reference for future research and clinical management.

Carbon nanomaterials can be obtained by the decomposition of lower hydrocarbon molecules using oxidized diamond-supported group VIII metal catalysts [1]. The obtained product is considered to be a carbon composite nanomaterial, i.e., a composite of a diamond (sp3 carbon) and a fibrous nanocarbon with sp2 bondings, named as a “Marimo carbon”. It is of a scientific and technological interest that the marimo carbon is expected to yield a wide variety of physical and/or chemical properties. In this study, we measured the field emission characteristics of the “Marimo carbon” to investigate the relation between the characteristics and their fine structure.