Expression of Aldo-Keto Reductase Family 1 Member B10 in the Early Stages of Human Hepatocarcinogenesis

Aldo-keto reductase family 1, member B10 (AKR1B10), a cancer-related oxidoreductase, is expressed in well-differentiated hepatocellular carcinomas (HCCs). However, AKR1B10 levels are minimal in normal liver tissues (NLs), similar to the 70-kilodalton heat shock protein (HSP70) and glypican-3. Moreover, the role of AKR1B10 in chronic hepatitis or cirrhosis, which are considered preneoplastic conditions for HCC, has not been fully elucidated. The aim of this study was to evaluate the expression of AKR1B10, HSP70, and glypican-3 in 61 HCC tissue samples compared to corresponding non-tumorous liver tissues (NTs), comprising 42 chronic hepatitis and 19 cirrhosis cases to clarify the significance of molecular changes at the preneoplastic stages of HCC. Immunohistochemical analysis demonstrated that the median expression levels of AKR1B10 were higher in HCCs than in NTs (p < 0.001) and higher in NTs than NLs (p < 0.001) with 54.8%, 2.1%, and 0.3% expression in HCCs, NTs, and NLs, respectively. HSP70 and glypican-3 were expressed in HCCs, but minimally in NTs and NLs with no significant difference between expression in NTs and NLs. Furthermore, a multivariate analysis identified an association between hepatic steatosis and AKR1B10 expression in NTs (p = 0.020). Of the three protein expressed in well-differentiated HCCs, only AKR1B10 was upregulated in preneoplastic conditions, and a steatosis-related factor might influence its expression.     

Fatigue strength of 316L-type stainless steel in simulated body fluids

The fatigue strength of commercial SUS316L stainless steel was studied in PBS(−) (phosphate buffer solution) with different dissolved oxygen contents and CPBS (a 0.9 mass% NaCl-containing citric phosphate buffer solution) with different pH levels, i.e., 5.0, 6.0, and 7.5. The results obtained are as follows. (1) The fatigue behaviour in PBS(−) was hardly affected by the dissolved oxygen content. (2) The fatigue strength in a high-cycle region was much lower in CPBS of pH 7.5 than in PBS(−) of pH 7.5. (3) The fatigue strength in CPBS decreased with decreasing pH from 7.5 to 5.0.     

3D imaging of lightning channel and leader progression velocity

Three‐dimensional imaging of lightning channels by means of UHF interferometers is performed. To realize this, a field campaign was conducted with two observation sites in Darwin, Australia. The distance between the two sites is about 14 km, and the triangulation scheme is applied to estimate locations of UHF radiation sources. Since the UHF radiation is more likely during the leader progression than in the return stroke phase, imaging of lightning channels is obtained mainly for downward leaders. Velocities of downward leaders are estimated and statistics are presented for first and subsequent strokes. The result is consistent with those of former investigations obtained by optical observations. The statistics for the velocity of leader propagation inside thunderclouds are presented herein. Using optical measurement, velocity estimation of leader progressions inside thunderclouds is impossible, and the presented results are concluded to be the first results of their kind. © 2001 Scripta Technica, Electr Eng Jpn, 137(3): 22–28, 2001     

Evaluation of Beer Bitterness by Measuring the Adsorption on a Lipid‐coated Quartz‐crystal Microbalance

The adsorption of beer constituents on a lipid membrane, measured using a lipid‐coated quartz crystal microbalance, showed a significant correlation with its bitter intensity and bitter duration in a sensory evaluation. The isohumulones and tetrahydroisohumulones increased the adsorption of beer on the lipid membrane. It appears that sensory bitterness can be objectively evaluated by measuring the adsorption characteristics of beer on the lipid membrane.     

Hydroxyapatite-induced alkaline phosphatase activity of human pulp fibroblasts

Hydroxyapatite is widely used clinically in the field of dentistry, however, the modulating action of hydroxyapatite with respect to the cells has not been investigated. In this study, it is described that one of the cytokines released by fibroblasts can cause increasing alkaline phosphatase (ALPase) activity of fibroblastsin vitro. Human pulp fibroblasts (HPFs) were cultured with hydroxyapatite (30–480 µg cm^–2) in serum-supplemented medium for 6 to 96 h, then the serum-free conditioned medium was obtained and added to sub-cnfluent HPF cultures. Significantly enhanced ALPase activity was detected when HPFs were incubated with the conditioned medium. This HPF-derived activity which induces increasing ALPase activity appeared in the conditioned medium with a 12h culture period, and the appearance of this mediator was completely inhibited in the presence of cycloheximide. Enhanced ALPase activity is detected in lesions in which calcification is occurring. The results of this experiment suggest that HPFs in contact with hydroxyapatite serve as a mediator in cell-to-cell interaction, and are related to the functional differentiation of cells for tissue repair including pulpal calcification.     

Preparation and photocatalytic activity of porous spherical TiO2 particles comprised of H3PW12O40 in hydrophobic nanopores

Porous TiO₂ sphere particles were prepared by impregnating titanium (IV) oxysulfate solutions into organic monolith particles, with subsequent calcination in air. The powder possessed pores of meso-order. Its crystalline phase was anatase. Then, 12 Tungsto(VI) phosphoric acid (PW₁₂) was present in the mesopores. The entire surface was modified to be hydrophobic by octadecylphosphonic acid (ODP). Subsequent UV illumination in water removed the PW₁₂ and ODP adsorbed onto the outer sphere surface. The obtained spherical TiO₂ particles with hydrophobic acidic nanopores exhibited high photocatalytic performance against the removal of 1,4-dioxane in water. Detailed analysis revealed that this material removed both 1,4-dioxane and ethylene glycol diformate (EGDF), the main intermediate of the photocatalysis of 1,4-dioxane. Results suggest that hydrophobic acidic nanopores enhance adsorption of EGDF in water and play an important role in the overall photocatalytic performance of this system.     

Viscoelastic and fragmentation characters of model bolus from polysaccharide gels after instrumental mastication

Model bolus from polysaccharide gels was investigated by the stress-relaxation tests and particulate size analyses. Using two gelling agents, gellan gum and a composite of gellan/psyllium seed gums, gels with different physical properties (i.e., elastic gellan single gels and plastic composite gels) and gel hardness were prepared. Gels were masticated instrumentally in the presence or absence of artificial saliva to prepare model bolus. Data from the stress-relaxation tests analyzed by 5-element mechanical model showed that difference between two Maxwell-bodies in the elasticity for the composite gels was generally smaller than that for gellan single gels when compared at equivalent gel hardness and was less influenced by the addition level of saliva. For each gel sample, cumulative particulate size distribution of model bolus was reduced logarithmically with a normal curve regardless of the addition level of saliva. Mean particulate size of model bolus from the composite gels was generally larger than that for gellan single gels when compared at equivalent gel hardness and was less influenced by the addition level of saliva. Based on the particulate size distribution of model bolus, coefficients of skewness and kurtosis calculated for the composite gels tended to be larger than those for gellan single gels when compared at equivalent gel hardness. Results indicated higher structural homogeneity of model bolus from the composite gels, which is related to higher miscibility with saliva. Structural homogeneity should be the key for texture design of nursing-care foods, particularly for dysphagia.     

Characteristics of SiH4/H2 VHF plasma produced by short gap discharge

A SiH₄/H₂ VHF plasma was produced with the multi rod electrode and the fundamental plasma parameters were examined as a function of pressure and power, where the frequency of the power source was 60 MHz. It was found that the ion saturation current takes a peak at a certain power as well as pressure. These results were discussed from the point of view of electron trapping effect in VHF electric fields. In addition, anomalous reduction of the sheath potential was observed.     

Chemotaxis assays of mouse sperm on microfluidic devices

Sperm chemotaxis is an area of significant interest to scientists involved in reproductive science. Understanding how and when sperm cells are attracted to the egg could have profound effects on reproduction and contraception. In an effort to systematically study this problem, we have fabricated and evaluated a microfluidic device to measure sperm chemotaxis. The device was designed with a flow-through configuration using a spatially and temporally stable chemical gradient. Mouse sperm cells were introduced into the chemotaxis chamber between confluent flows of mouse ovary extract and buffer. The sperm experiencing chemotaxis swam toward the extract and were counted relative to those that swam toward the buffer. The ovary extracts were diluted from 10(2) to 10(7) times, and each extract dilution was screened for chemotaxis. Four out of six ovaries showed a strong chemotactic response at extract dilutions of 10(-3) to 10(-5). This device provided a convenient, disposable platform on which to conduct chemotaxis assays, and the flow-through design overcomes difficulties associated with distinguishing chemotaxis from trapping.     

Preparation of porous spherical ZrO2–SiO2 composite particles using templating and its solid acidity by H2SO4 treatment

Porous ZrO₂–SiO₂ composite sphere particles were prepared by impregnating precursor solutions into organic monolith particles, with subsequent calcination in air. The porous spheres possessed uniformly sized pores of around 10 nm. Addition of SiO₂–ZrO₂ decreased the ZrO₂ crystallinity and increased the specific surface area. The acid amount on the surface of the composite spheres was increased by treatment with H₂SO₄. The acid strength and its amount, including the Lewis/Br?nsted acid ratio, depended on the SiO₂/ZrO₂ ratio and the H₂SO₄ concentration. The powder treated under an optimum condition exhibited higher solid acidity than the reference solid acid catalyst. The prepared porous SO₄ ²⁻/ZrO₂–SiO₂ spheres showed higher saccharization activity than the reference solid acid catalyst did.