Effect of 5-fluorouracil and UFT on experimental liver metastasis model of colorectal cancer using mouse colon 26 cells

Effects of 5-fluorouracil (5-FU) and UFT on an experimental liver metastasis model were compared at equi-effective dosage levels against subcutaneous tumor of mouse colon 26. 5-FU at the dosage level of 40 mg/kg suppressed the subcutaneous tumor growth by 70.0% and 45.0% on day 13 and day 18, respectively, and UFT at 20 mg/kg provided almost equal suppression (63.0% and 48.0%). In the liver metastasis model, 5-FU at 40 mg/kg showed more potent prevention of the formation of metastatic foci (94.9%) than did UFT (60.4%) at 20 mg/kg. 5-FU at 40 mg/kg produced a much higher peak serum level of 5-FU than did UFT at 20 mg/kg and also showed a much higher AUC (area under the curve) level in the portal blood. These results suggest that oral administration of 5-FU might be useful in prevention of liver metastasis of colorectal cancer.     

Purification, characterization, and mechanism of a flavin mononucleotide-dependent 2-nitropropane dioxygenase from Neurospora crassa

A nitroalkane-oxidizing enzyme was purified to homogeneity from Neurospora crassa. The enzyme is composed of two subunits; the molecular weight of each subunit is approximately 40,000. The enzyme catalyzes the oxidation of nitroalkanes to produce the corresponding carbonyl compounds. It acts on 2-nitropropane better than on nitroethane and 1-nitropropane, and anionic forms of nitroalkanes are much better substrates than are neutral forms. The enzyme does not act on aromatic compounds. When the enzyme reaction was conducted in an 18O2 atmosphere with the anionic form of 2-nitropropane as the substrate, acetone (with a molecular mass of 60 Da) was produced. This indicates that the oxygen atom of acetone was derived from molecular oxygen, not from water; hence, the enzyme is an oxygenase. The reaction stoichiometry was 2CH3CH(NO2)CH3 + O2-->2CH3COCH3 + 2HNO2, which is identical to that of the reaction of 2-nitropropane dioxygenase from Hansenula mrakii. The reaction of the Neurospora enzyme was inhibited by superoxide anion scavengers in the same manner as that of the Hansenula enzyme. Both of these enzymes are flavoenzymes; however, the Neurospora enzyme contains flavin mononucleotide as a prosthetic group, whereas the Hansenula enzyme contains flavin adenine dinucleotide.     

Analytical studies of four-inch pipe whip tests under BWR LOCA conditions

The purpose of pipe rupture studies in JAERI is to perform model tests on pipe whip, restraint behavior, jet impingement and jet thrust force, and to establish a computational method for analyzing these phenomena. This report presents the analytical results of 4-inch pipe whip tests under BWR LOCA conditions.Dynamic response analyses were performed using the general-purpose finite element program ADINA. The test pipe was modelled by straight beam elements and the four restraints were modelled by a single truss element. The analytical results were compared with the experimental results. Impact time and maximum total restraint force showed good agreement with experimental results. On the other hand, pipe strain and pipe deflection could not be predicted so well. The reason for this is that the sliding of the restraint during the pipe whip movement cannot be considered in the analyses.     

The role of aluminum in automotive weight reduction—part III

This series of articles provides, from an international perspective, an analysis of the future of the automotive industry and aluminum’s role in automobile weight reduction. Part I briefly described technological, environmental, and societal issues that are mandating vehicular weight reduction for, among other reasons, purposes of fuel economy. Part II described the status of the weight-reduction technologies that are currently available and projects how they may evolve in the coming years. Part III, the final installment, examines some of the specific strengths and weaknesses of aluminum alloys with regard to their long-term attractiveness to automakers.     

Polarization-controlled single-mode VCSEL

Relative intensity noise (RIN) in a vertical-cavity surface-emitting laser (VCSEL) was greatly reduced through the use of polarization control to eliminate competition between two orthogonal polarization states by ensuring there was only one polarization state. Polarization was stable with optical feedback of up to 10%. Polarization control was achieved by inducing a small loss anisotropy in fundamental transversal mode VCSEL's. Anisotropic post structures, such as a rectangular post, an oblique post, or a zigzag-sidewall post, were found to be effective in creating loss anisotropy without serious degradation of other VCSEL characteristics such as light-output power or beam profile     

Immunohistochemical profile of basic fibroblast growth factor and heparan sulphate in adult rat mandibular condylar cartilage

Basic fibroblast growth factor (bFGF) and heparan sulphate (HS) were detected immunohistochemically in mandibular condylar cartilage, and the findings compared with those on epiphyseal articular cartilage. In the condylar cartilage, both bFGF and HS were localized in chondrocytes throughout the various zones including the fibrous, proliferative, mature-cell and hypertrophic zones: bFGF immunostaining was most significant in the proliferative and mature-cell zones, while intense staining for HS was found mainly in the hypertrophic zone. Immunoreaction for bFGF was detected in the nuclei of chondrocytes, whereas HS staining was observed in the cytoplasm. In articular cartilage, only chondrocytes beneath the superficial zone (intermediate zone) demonstrated both bFGF and HS immunoreactivities. Chondrocytes in the deeper calcifying region of the articular cartilage did not immunoreact for either bFGF or HS. These findings suggest that, in contrast to the epiphyseal articular cartilage, a continuous bFGF-mediated remodelling of cells and matrix takes place in mandibular condylar cartilage during the process of endochondral ossification.     

Radiation-induced polymerization of ethylene in pilot plant. III. Heavy-phase recycling process

Radiation-induced polymerization of ethylene using aqueous tert-butyl alcohol as medium was carried out in a large-scale pilot plant with a 50-liter central source-type reactor at a pressure of 105 to 395 kg/cm², temperature of 30° to 80°C, mean dose rate of 4.5 × 10⁴ to 1.9 × 10⁵ rads/hr, ethylene feed rate of 5.5 to 23.5 kg/hr, and medium feed rate of 21 to 102 l./hr. The space–time yield and molecular weight of the polymer were in the range of 4.7 to 16.8 g/l.-hr and 1.3 × 10⁴ to 8.9 × 10⁴, respectively. The space–time yield and molecular weight increased with mean residence time at 30°C, whereas at 80°C they became almost independent of the time. The space–time yield increased with pressure and dose rate, slightly decreased with temperature, and was maximum at ethylene molar fraction of 0.5. The polymer molecular weight increased with pressure and ethylene molar fraction, and decreased with dose rate and temperature. The total amount of deposited polymer on the reactor wall, source case wall, and scraping blades was usually less than 1 kg, which was negligibly small for the analysis of polymerization. Continuous discharge of the polymer slurry and production of fine-powder polyethylene were successfully carried out. In the central source-type reactor, a dose rate of 1.9 × 10⁵ rads/hr was obtained with a ⁶⁰Co source of ca. 12 kCi.     

Determination method of equivalent insulation test voltage at room temperature for high temperature superconducting power apparatus with coil structure

This paper deals with the determination method of the equivalent insulation test voltage at room temperature that secures the reliability of the cryogenic electrical insulation of the high temperature superconducting (HTS) power apparatus. The high voltage test is related to the apparatus with coil structure at the stages of its development, manufacturing and shipment. In the test method, the equivalent insulation test voltage at room temperature is derived from the standard test voltage at cryogenic temperature, based on the idea that the HTS power apparatus should be operated without partial discharges (PDs). The conversion factor between the two voltages is given by the product of the two medium factors, i.e. the one relating to the potential distribution along the coil winding and the other relating to the PD inception condition at the weakest part in the electrical insulation system. In order to determine the latter factor concerned with the non-linear phenomena against electrical stresses, the PD inception voltages at cryogenic and room temperatures are theoretically and experimentally estimated for modeled turn-to-turn insulation system. The results show that both estimated and measured values are in fairly good agreement and the proposed method is useful for the equivalent high voltage test at room temperature for the HTS power apparatus.