Showing papers by "Hokkaido University published in 1986"

Hepatoid adenocarcinomas of the stomach. An analysis of seven cases.

Abstract: Hepatoid adenocarcinomas of the stomach are gastric carcinomas with both adenocarcinomatous and hepatocellular differentiations. They usually produce large amounts of alpha-fetoprotein (AFP) with a Concanavalin A-binding property of hepatic type. In this study, these carcinomas occurred in older persons, with the antrum being a common site. Observed grossly, growth of the tumors was nodular and massive. Prognosis was poor because of frequent liver metastases. In the cytoplasms of tumor cells, various serum proteins were identified, including AFP, alpha-1 antitrypsin (AAT), alpha-1 antichymotrypsin (ACT), albumin, and prealbumin. Localizations of ferritin, prothrombin, and transferrin were demonstrated with less frequency. Adenocarcinomatous foci were composed of well-differentiated, intestinal-type epithelial cells and often contained carcinoembryonic antigen. These adenocarcinomatous and hepatoid areas were often intermingled with each other. There were extensive venous involvements by tumor cells. The poor prognosis of the tumors may be attributed to these involvements as well as to production of AFP and presence of AAT/ACT, which have immunosuppressive and protease-inhibitory properties, respectively.

Study on the oxidative rate and prooxidant activity of free fatty acids

Abstract: Oleic, linoleic and linolenic acids were autoxidized more rapidly than their corresponding methyl esters. Addition of stearic acid accelerated the rate of autoxidation of methyl linoleate and the decomposition of methyl linoleate hydroperoxides. Therefore, the higher oxidative rate of FFA’s than their methyl esters could be due to the catalytic effect of the carboxyl groups on the formation of free radicals by the decomposition of hydroperoxides. Addition of stearic acid also accelerated the oxidative rate of soybean oil. This result suggests that particular attention should be paid to the FFA content that affects the oxidative stability of oils.

Lipid Composition of Plasma Membranes and Tonoplasts Isolated from Etiolated Seedlings of Mung Bean (Vigna radiata L.)

Abstract: The lipid composition of plasma membranes and tonoplasts from etiolated mung bean hypocotyls was examined in detail. Phospholipids, sterols, and ceramide monohexoside(s) were the major lipid classes in both membranes. The content of phospholipids on a protein basis was higher in the tonoplast, but the content of total sterols was similar in both membranes. Accordingly, the sterol to phospholipid molar ratio in the plasma membrane was higher than that of the tonoplast. Phosphatidylethanolamine and phosphatidylcholine comprised the major phospholipids in both membranes. Phosphatidylinositol, phosphatidylserine, and phosphatidylglycerol were identified as minor phospholipid components. The content of phosphatidylinositol and phosphatidylglycerol was relatively high in the tonoplast, comprising 11 and 5% of the total phospholipids, respectively. Although special care was taken against the degradative action of phospholipase D and phosphatidic acid phosphatase during the isolation of these membranes, by adding EDTA, EGTA, KF, choline, and ethanolamine to the homogenizing medium, significant amounts of phosphatidic acid, about 15% of the total phospholipids, were detected in the plasma membrane. On the other hand, the content of phosphatidic acid in tonoplasts and other membrane fractions was very low. This fact may indicate that high levels of phosphatidic acid occur naturally in plasma membranes. Phosphatidylglycerol in both membranes and phosphatidylinositol in the tonoplast contained high levels of palmitic acid, which comprised more than 50% of the total fatty acids. Significant differences were observed in the sterol compositions of plasma membranes and tonoplasts. More than 90% of the sterols in the plasma membrane were unesterified, while the tonoplast was enriched in glycosylated sterols, especially acylated sterylglycosides. Ceramide monohexoside was found to be specifically located in these membranes, in particular, in the tonoplast, in which it comprised nearly 17% of the total lipids.

Non-invasive ultrasonic measurement of the elastic properties of the human abdominal aorta

Abstract: A new echo tracking device linked to real time ultrasonic B mode equipment was developed to measure non-invasively the elastic properties of the human abdominal aorta. Pulsatile diameter change and mean diameter of the abdominal aorta were measured in 61 subjects with this ultrasonic device. Strain and pressure-strain elastic modulus Ep were calculated from pulsatile diameter change, diameter, and pulse pressure obtained by the auscultatory method. Strain significantly decreased with age; 0.076(0.024) (mean(SD)) in group 1 (20 young adults below the age of 35 years); 0.048(0.024) in group 2 (21 middle aged subjects between the ages of 35 and 60 years); and 0.030(0.010) in group 3 (20 elderly subjects over the age of 60 years). Ep values were 0.99(0.34)× 105, 1.55(0.68)× 105, and 3.80(2.05)× 105 N·m−2 in groups 1, 2, and 3 respectively. Ep in group 3 was significantly higher than in groups 1 and 2. The regression equation relating Ep to age was Ep = (−0.72 + 0.058×age)×l05 N·m−2 (r=0.73). The Ep value and its age related increase agreed with the findings in postmortem arteries. The elastic properties of the abdominal aorta could, therefore, be determined non-invasively by this ultrasonic method.

Raman Spectroscopy of Thin Corrosion Films on Iron at 100 to 150 C in Air

Abstract: Laser Raman spectroscopy (LRS) has been applied for the detection and characterization of thin corrosion films formed on iron in air at a temperature range from 100 to 150 C. In situ ellipsometric measurements have also been conducted for quantitative estimations of the film growth kinetics. It is found that (1) the oxidation of iron in dry air leads to the formation of a surface oxide film composed primarily of magnetite and (2) the water vapor in air accelerates the formation of hematite. The ratio of magnetite to hematite in the surface oxide film appears to increase with (1) increasing water vapor pressure, (2) ascending temperature, and (3) extending oxidation time.

Ca2+-induced alteration in the unfolding behavior of alpha-lactalbumin.

Abstract: Comparative studies of the unfolding equilibria of two homologous proteins, bovine alpha-lactalbumin and hen lysozyme, induced by treatment with guanidine hydrochloride have been made by analysis of the peptide and the aromatic circular dichroism spectra. The effect of the specific binding of Ca2+ ion by the former protein was taken into account in interpreting the unfolding equilibria of the protein. Proton nuclear magnetic resonance spectra of alpha-lactalbumin were also measured for the purpose of characterizing an intermediate structural state of the protein. In previous studies, alpha-lactalbumin was shown to be an exceptional protein whose equilibrium unfolding does not obey the two-state model of unfolding, although lysozyme is known to follow the two-state unfolding mechanism. The present results show that the apparent unfolding behavior of alpha-lactalbumin depends on Ca2+ concentration. At a low concentration of Ca2+, alpha-lactalbumin unfolds with a stable intermediate that has unfolded tertiary structure, as evidenced by the featureless nuclear magnetic resonance and aromatic circular dichroism spectra, but has folded secondary structure as evidenced by the peptide circular dichroism spectra. However, in the presence of a sufficiently high concentration of Ca2+, the unfolding transition of alpha-lactalbumin resembles that of lysozyme. The transition occurs between the two states, the native and the fully unfolded states, and the cooperativity of the unfolding is essentially the same as that of lysozyme. Such a change in the apparent unfolding behavior evidently results from an increase in the stability of the native state relative to that of the intermediate induced by the specific Ca2+ binding to native alpha-lactalbumin. The results are useful for understanding the relationship between the protein stability and the apparent unfolding behavior.

Moonlight avoidance behavior in Leach's Storm-Petrels as a defense against Slaty-backed Gulls

Abstract: -Diurnal activity patterns of Leach's Storm-Petrels (Oceanodroma leucorhoa) and Slaty-backed Gulls (Larus schistisagus) were investigated. The petrels reduced activity in moonlight in May and June when the predation rate by gulls was relatively high. Petrel activity levels were inversely correlated with light intensities and the corresponding risk of predation by the gull. This suggests that nocturnal activity and moonlight avoidance by the petrel in its colony are an effective defense against diurnal predators. Activity synchronization of the petrel was most marked during the full moon, further supporting the predatoravoidance hypothesis. Received 15 October 1984, accepted 27 April 1985. MANX Shearwater (Puffinus puffinus; Harris 1966), Leach's Storm-Petrel (Oceanodroma leucorhoa; Harris 1974), Fork-tailed Storm-Petrel (0. furcata; Harris 1974, Boersma et al. 1980), and Cassin's Auklet (Ptychoramphus aleuticus; Thoresen 1964, Manuwal 1974) are strictly nocturnal in their colonies and are less active on moonlit nights than on dark nights. Cody (1973) discussed the nocturnal activity of alcids as a defense against diurnal predators. Gross (1935), M. P. Harris (1966), and S. W. Harris (1974) also suggested that nocturnal procellariiforms are vulnerable to diurnal predatory gulls on moonlit nights. However, the relationship between daily activities of procellariiforms and predation risk has not been studied. I studied Leach's Storm-Petrels and Slatybacked Gulls (Larus schistisagus) on Daikoku Island. Their activity patterns are described and the nocturnal behavior of the petrels in the colony is discussed as predator avoidance. STUDY AREA AND METHODS The colony.-The study was conducted on Daikoku Island (42?52'N, 144?52'E), Akkeshi, Hokkaido, between late April and early October 1982. The island is 6.1 km in circumference and treeless, with the exception of birch (Betula ermanii) groves in the ravines. Leach's Storm-Petrel (the only petrel breeding on the island) nests in the interior parts of the island, which is covered with Artemisa montana and Urtica platyphilla. Abe et al. (1972) estimated that there were 1,070,000 breeding pairs of petrels, but a more recent estimate is 415,000 (Watanuki 1985b). About 3,500 pairs of Slaty-backed Gulls nested on maritime slopes, which are covered with Calamagrostis langsdorffii, isolated rock stacks, and cliff ledges. A few pairs of Blacktailed Gulls (L. crassirostris) nested on these sites. The Slaty-backed Gull is an important predator of adult petrels on the island. Although Jungle Crows (Corvus macrorhynchos) excavated petrel burrows and ate adults, eggs, and chicks, predation by the small crow population (13 pairs) was not significant. Activity patterns.-Observations of flying birds were made from a blind set on top of a headland about 25 m above sea level. For 5 min every 30 min, I counted all birds passing an imaginary 20 x 30-m plane oriented vertically with reference to the cliff face opposite the headland. Two 6-volt electric lights, one set horizontally and the other about 450 upward at the blind, lit the plane facing toward the sea from the lower corner to the opposite side. This reduced the effect of the light on landing birds approaching from the sea. If all the landing petrels were attracted instantaneously to the lights, the number of petrels flying through the lights would increase during the observations. However, the number was rather constant during 5-min observations (Fig. 1). A few petrels and gulls flew circularly in the lights; these were excluded from the data. Observations on moonlit nights showed that Slaty-backed Gulls did not avoid the lights. No differential response to the lights by gulls and petrels was assumed. Observations started in daylight and lasted 24 h (n = 19 days). Data taken during a day with dense fog (13-14 May) were excluded from the analysis because of low visibility. Data of 27-28 April were included in those of May. Light intensity was measured by a lux-meter (? 10%) set horizontally and was divided into four classes: dark (0 lux), moonlight with no cloud cover ( 5 x 104 lux). Time of sunrise, sunset, moonrise, and moonset were from the astronomical tables for Kushiro, about 40 km west of Daikoku Island. 14 The Auk 103: 14-22. January 1986 This content downloaded from 207.46.13.75 on Fri, 08 Jul 2016 05:57:15 UTC All use subject to http://about.jstor.org/terms January 1986] Moonlight Avoidance in Leach's Petrel 15

Vectorial Finite-Element Method Without Any Spurious Solutions for Dielectric Waveguiding Problems Using Transverse Magnetic-Field Component

Abstract: An improved finite-element method for the analysis of dielectric waveguiding problems is formulated rising the transverse magnetic-field component. In this approach, the divergence relation /spl nabla/ · H = 0 is satisfied and the spurious, nonphysical solutions which have been necessarily included in the solutions of earlier vectorial finite-element methods are completely eliminated in the whole region of a propagation diagram. To verify the accuracy of the present method, numerical results for a rectangular metallic waveguide half filled with dielectric are presented and compared with exact and earlier finite-element solutions. Dielectric rectangular waveguides are also analyzed for both isotropic and anisotropic cases.

Macrophage activation with multi-porous beads prepared from partially deacetylated chitin

Abstract: The effect of multi-porous beads prepared from 80% deacetylated chitin on the activation of mouse peritoneal macrophages was examined. Deacetylated chitin bead (DAC-bead) preparations were shown to activate macrophages for tumoricidal activity depending on the increasing concentration of acetic acid used for the pretreatment of beads. The large DAC-bead was more susceptible to treatment with acetic acid than small DAC-bead, and showed more potent capacity for the activation of macrophages under the same pretreatment conditions with acetic acid. Deacetylated bead preparations, on the other hand, showed less activities. In addition, DAC-bead pretreated with acetic acid stimulated macrophages to produce interleukin 1. The possibilities of multi-porous beads as cancer chemotherapeutic-carrier were examined by the method of column chromatography and of in vitro antitumor experiment. Forty-four percent of adriamycin adsorbed on the surface of and in bead was released within the first 60 min. of elution, and then adriamycin was released more slowly in proportion to the elution time. Antitumor activity of adriamycin-adsorbed bead was less effective than that of free adriamycin if they were compared on the basis of total content of adriamycin.

Application of the Boundary-Element Method to Waveguide Discontinuities (Short Paper)

Abstract: A numerical method for the solution of scattering of the H-and E-plane waveguide junctions is described. The approach is a combination of the boundary-element method and the analytical method. A general computer programs has been developed using the quadratic elements (higher order boundary elements). To show the validity and usefulness of this formulation, computed results are given for a right-angle corner bend, a T-junction, an inductive strip-planar circuit mounted in a waveguide, a waveguide-type dielectric filter, and an inhomogeneous waveguide junction, and a linear taper. Comparison of the present results with the results of the finite-element method shows good agreement.

Magnetic field induced multi-component QED 3 and quantum Hall effect

Abstract: Dynamics of two dimensional electrons under the strong perpendicular magnetic field is shown to be described by a multi-component fermion theory. The electric conductance has a remarkable property known as the quantum Hall effect. The Hall conductance is quantized in units ofe2/h in the gap region and in the localized state region. The proof of exactness is presented in general cases using quantum field theory.

Raman spectra of the anodic oxide film on titanium in acidic sulfate and neutral phosphate solutions

Abstract: Laser Raman spectroscopy has been applied under in situ and ex situ conditions to the anodic oxide films formed on titanium at various potentials in neutral phosphate and acidic sulfate solutions. The Raman spectra reveal that the anodic oxide film is primarily composed of an anatase type of . From the relation between the Raman band intensity, film thickness, and surface morphology, it is likely that the film changes from the amorphous state to the crystalline state beyond a certain critical potential.

Effect of stirring on crystallization kinetics of basalt: texture and element partitioning

Abstract: Isothermal crystallization experiments on basalt have been carried out using an infrared heating furnace to investigate the effect of stirring. When stirring was not applied (static experiment), the results agreed well with previous experiments. But when stirring was applied and a flow of Reynolds number=10−3∼−4 was present (dynamic experiment), considerably different results were obtained, especially in respect to the nucleation rate and the morphology of crystals. At ΔT=25° C essentially similar results were obtained on the nucleation rates and morphologies of crystals in both static and dynamic experiments. However, at supercoolings larger than 45° C, nucleation density increased drastically in dynamic experiments reaching up to ten times as large as that in static experiments. Crystals of plagioclase and clinopyroxene were small and adapted acicular morphology regardless of ΔT in dynamic experiments, and hyalopilitic textures were formed. A TTT-diagram shows that the nucleation incubation time is shorter in dynamic experiments than in static experiments. No compositional difference in major elements was found in plagioclase and clinopyroxene produced in both static and dynamic experiments. However, minor element concentrations, e.g., Mg in plagioclase and Ti, Al in clinopyroxene, were found to increase with both ΔT and flow velocity. All these results imply that although chemical diffusion in the melts did not play an important role in the dynamic experiments, interface kinetics were important. It is suggested that hyalopilitic texture commonly seen in natural basalt is mainly due to flow in magma.

Subluxation of the patella : Investigation by computerized tomography.

Abstract: Subluxation of the patella may produce pain and instability in young people. However its classification, diagnosis and treatment are controversial. We have used computerized tomography (CT) to measure the amount of lateral shift of the patella and the angle of tilt to the femur in patients with subluxation. The mean lateral shift was 31.4% and the angle of tilt 31.8 degrees. These values are significantly greater than those obtained from conventional axial radiographs or in arthrographic axial views.We have obtained interesting evidence that the rate of lateral shift apparently increased on voluntary contraction of the quadriceps muscle (Q-contracted). With the quadriceps contracted, the mean rate of the lateral shift in the affected knees showed a significant increase (+ 27.7%) compared to that in normal knees (+ 14.0%).We have reviewed 40 knees treated by operative realignment with a mean follow-up of 27 months. The mean rates of lateral shift measured from CT-image in the knees before operation improved significantly to the normal range at follow-up, both with the quadriceps relaxed and contracted. The results evaluated by Insall's criteria were "excellent" in 13 knees; "good" in 22; "fair" in 3 and "poor" in 2. The satisfactory group (those with excellent and good results) revealed an improvement in lateral shift when the quadriceps was contracted, while the unsatisfactory group (fair and poor results) did not.

A numerical experiment on nonlinear image reconstruction from first-arrival times for two-dimensional island arc structure

Abstract: Many inversion studies of first P-arrival times have been made for the threedimensional upper mantle structure beneath the Japanese Islands by using the linear damped least-squares method (AKI and LEE, 1976). One of the most recent contributions relying on this method is that by HASEMI et al. (1984) on the structure beneath the Tohoku region. In the linear inversion it is assumed that the ray paths in the inverted model are the same as those in the initial model. The ray tracing experiments attempted in the early 1970's (JACOB, 1970) showed that the ray paths are strongly guided by the high velocity slabs descending beneath the island arcs. The aim of this study is to examine the performance of a nonlinear inversion of travel times of first-arrivals for the island arc structure. We apply the Dijkstra method (DIJKSTRA, 1959) of network theory in the forward calculation of ray paths and travel times instead of the shooting or bending method (JULIAN and GUBBINS, 1977). We subdivide a two-dimensional space of 100 km x 100 km into a number of blocks of 10 km x 10 km as shown in Fig. 1. We assume an average layered velocity profile of the area under consideration a priori. We make the velocity profile by taking the value of the JMA standard P-wave structure (HAMADA, 1984) for each 10 km starting from a depth of 5 km. The algorithm proposed by DIJKSTRA (1959) is considered to be the fastest of the algorithms which find the shortest paths connecting a node and the other all nodes of a network (IRI and KOBAYASHI, 1976). For the algorithm, one should consult DIJKSTRA (1959) or IRI and KOBAYASHI (1976). We seek the shortest time paths connecting a node ns and the other all nodes ni(j_??_s) of the network. When the node ns is assigned to an event, and the nodes n;(j 0 s) include station positions, we are able to obtain the shortest time paths from the event to all the stations. When the node ns indicates a station and all the event locations are included in nj(j # s), the algorithm gives us the shortest time paths from all the events to the station. In this study we shall put the nodes on the boundaries of the blocks. Figure 1 shows a laterally heterogeneous model that corresponds to a vertical section of the uppermost mantle perpendicular to the strike of island arcs. The

A Parameter Describing Overall Conditions of Wave Breaking, Whitecapping, Sea-Spray Production and Wind Stress

Abstract: The dim ensionless parameter u * 2 /vσ can be used widely as a parameter to describe the overall conditions of air-sea boundary processes, where u* is the friction velocity of air, v is the kinematic viscosity of air and s is the spectral peak frequency of the wind waves A critical value of this parameter for the appreciable commencement of breaking of wind waves is 103 Beyond this value, the percentage of waves passing a fixed point that are breaking, α, and the percentage of whitecap coverage, P, are both approximately proportional to this parameter The number concentration of sea-salt particles containing salt in the vicinity of 10−10 g at the 6-m level is also proportional to this parameter The dimensionless roughness length associated with the air flow over water, u*Z0 /V, also correlates better with this parameter than with a parameter which does not contain the spectral peak frequency This gives an approximate relation of z0 σ/u* = 0025, and a corresponding formula for the drag coefficient is proposed The dimensional and physical interpretation of the parameteru */2/vσ is presented