Biosynthesis of PP-V, a monascorubramine homologue, by Penicillium sp. AZ

The biosynthetic pathway of PP-V, a new monascorubramine homologue, was elucidated by 13C-labeling studies. The [1-13C] of acetate was incorporated into 2-, 3a-, 4a-, 6-, 8-, 9-, 11-, 13-, 15-, 17-, and 19-Cs of PP-V, and the [2-13C], into 3-, 4-, 5-, 8a-, 9a-, 10-, 12-, 14-, 16-, 18-, and 20-Cs. These incorporation patterns coincide with those reported in the biosynthesis of a Monascus azaphilone pigment, monascorubrin.     

High-throughput immunophenotyping by surface plasmon resonance imaging

Cell binding assays on antibody arrays permit the rapid immunophenotyping of living cells. The throughput of the analysis, however, is still limited due to our inability to perform parallel and quantitative detection of cells captured on the array. To address this limitation, we employed here an imaging technique based on surface plasmon resonance (SPR). SPR has been frequently used to monitor capture of proteins on antibody microarrays, while few cases were reported for capture of cells. Antibody arrays were prepared through the photopatterning of an alkanethiol monolayer on a gold-evaporated glass plate and the subsequent immobilization of various antibodies onto 4-9 separate spots created by photopatterning. A glass slip was mounted onto the array with a thin spacer to construct a parallel-plate chamber. Leukemia cells were injected into the chamber to conduct a binding assay, while refractive index changes at the vicinity of the array surface were monitored by SPR imaging. We observed that SPR signals were intensified on specific antibody spots but not on nonspecific spots. Confocal laser scanning microscopy revealed that the observed SPR signals were attributed to cell deformations caused by multivalent interactions with immobilized antibody, which effectively elevated the refractive index of a medium phase within an evanescent field. This effect could be suitably utilized to monitor quantitatively cell binding to multiple spots from a heterogeneous cell population.     

Design and control of a microrobotic system using magneticlevitation

Presents a prototype microrobot based on magnetic principles. Miniature items are to be transported and assembled in hazardous environments. A microrobot can be remotely operated with 3 DOF in an enclosed environment by transferring magnetic energy and optical signals from outside. The magnetic drive unit consists of 8 electromagnets (4 pairs), 2 permanent magnets, a return yoke and a pole piece. The microrobot is manipulated under the pole piece by regulating magnetic field. It consists of a magnetic head, a body (electronic circuit and batteries), and copper alloy ribbon ringers. A shape memory alloy actuator activates the fingers by illuminating/extinguishing several LED. PID controls were applied. To cope with uncertainties and variations in payload masses, an adaptive control law was also employed for positioning along the z axis to enable the controller parameters to be adjusted in real-time. Effectiveness of the control was verified by the results of several experiments. The microrobot has a net mass of 8.1 g and it can elevate and manipulate objects with masses up to 1.5 g within a volume of 29×29×26 mm³ with a precision of 0.05 mm     

Role of peritoneal lavage smears and gastric wall brushing smears in gastric cancer surgery

Examinations of peritoneal lavage smears (LC) and gastric wall brushing smear cytology (BC) appear to be important for determining accurately the stage of gastric cancer. We have been carrying out such examinations during gastric cancer surgery for 7 years. In the present study, we evaluated the results obtained from 287 patients with gastric cancer. Tumor invasion and peritoneal dissemination were correlated with a positive incidence of cancer cells in LC and/or BC. Gastric cancer showing serosal invasion was classified into positive for LC and/or BC and negative for LC and/or BC. Patients positive for LC and/or BC had a poorer prognosis. For future gastric cancer treatment, patients positive for peritoneal cytology are expected to be targeted for intensive treatment during or before surgery.     

Effects of an antiallergic drug, pemirolast potassium on tyrosine phosphorylation and map kinase activation in antigen-stimulated rat basophilic leukemia (RBL-2H3) cells

Aggregation of high affinity IgE Fc receptors (Fc epsilon RI) on RBL-2H3 cells results in tyrosine phosphorylation of 33-, 42-, 44-, 72-, 80-, 90-, 125-kDa proteins. The 42 and 44 kDa proteins were identified as mitogen-activated protein (MAP) kinases with immunoblotting of anti-MAP kinase antibody. The effects of an antiallergic drug, pemirolast potassium (TBX) on Ag-induced protein tyrosine phosphorylation and MAP kinase activation were investigated. When RBL-2H3 cells were stimulated with Ag in the presence of TBX, tyrosine phosphorylation of three proteins (33, 42 and 44 kDa) was inhibited concentration-dependently (0.1-10 micrograms/ml). Inhibition of Ag-induced tyrosine phosphorylation of 33 kDa protein, which could be a beta subunit of Fc epsilon RI, suggests that TBX may prevent the activation of Fc epsilon RI. TBX suppressed activation of MAP kinases (42 and 44 kDa) in response to Ag as well as phorbol myristate acetate (100 nM) or calcium ionophore A23187 (500 nM), implying that the drug acts on signal transduction component(s) between the second messengers and MAP kinases. However, TBX had no effects on protein tyrosine phosphorylation and MAP kinase activation in MC3T3-E1 osteoblastic cells. These results indicate that TBX may affect Fc epsilon RI and also may act as a step distal of Ca2+ mobilization and protein kinase C activation leading to MAP kinase activation in RBL-2H3 cells.     

Protective effect of lysozyme-galactomannan or lysozyme-palmitic acid conjugates against Edwardsiella tarda infection in carp, Cyprinus carpio L

The protective effect of lysozyme-galactomannan or lysozyme-palmitic acid conjugates orally administered to carp, Cyprinus carpio L. was investigated using a virulent strain of Gram-negative Edwardsiella tarda isolated from an infected fish. Lysozyme-galactomannan conjugate was prepared through controlled Maillard reaction. Lysozyme-palmitic acid conjugate was prepared through base-catalyzed ester exchange using N-hydroxysuccinimide ester of palmitic acid. The conjugates provided substantial protection to carp infected with a Gram-negative bacteria fish pathogen E. tarda NG 8104. Lytic activities of lysozyme conjugates with galactomannan and palmitic acid were about 80 and 71% of native lysozyme using Micrococcus lysodeikticus as a substrate. Feeding with lysozyme conjugates, for 8 days, significantly enhanced fish protection against E. tarda infection. The survival rate was 30% for lysozyme-galactomannan conjugate treated fish and 20% for lysozyme-palmitic acid conjugate treated fish after 6 days cultivation while all control fish died within 3 days. On the other hand, a recovery rate of 40% after 6 days was observed in the fish group that were fed lysozyme-palmitic acid conjugate 3 and 2 h before and after E. tarda challenge, respectively, and for 6 consecutive days. The results of this work show the possibility of utilizing lysozyme conjugates with galactomannan or palmitic acid as a therapeutic for infection in fish.     

Study on the beam transport from the Bio-Nano ECRIS

The beam transport of N(+) ion and C(60)(+) ion in the Bio-Nano ECRIS with min-B configuration was investigated based on the ion beam profiles. The N(+) beam could be focused under the low-beam current conditions. Also the C(60)(+) beam could be focused in spite of the large space-charge effect which will lead the divergence of the beam. We confirmed that our beam transport system works well even for the C(60)(+) ion beam. We estimated the highest C(60)(+) beam current with the focused beam profile by comparing the N(+) ion beam.     

Deformation of Alumina/Titanium Carbide Composite at Elevated Temperatures

The deformation behavior of an Al₂O₃/30 wt% TIC composite in uniaxial tension was evaluated under vacuum over the temperature range of 1300° to 1550°C. The Al₂0₃/TiC composite exhibited the maximum elongation of 66% at an initial strain rate of 1.19 X l0^-4 s^-1 at 1550°C. The stress exponent calculated from peak stresses of true stress-true strain curves at 1500^OC was 3.8, which was in good agreement with that obtained by changing the crosshead speed during the tension test. The apparent activation energy at 20 MPa was 853 kJ/mol. In addition the deformation of the Al₂O³/TiC composite in uniaxial tension at elevated temperature was accompanied by cavitation.     

Formation of 2,4-dinitrophenylhydrazones in high-density polyethylene film irradiated with ultraviolet light

Polyethylene films were irradiated in air by ultraviolet light. 2,4-Dinitrophenylhydrazine was reacted on the irradiated films. The changes in amounts of carbonyl groups and 2,4-dinitrophenynlhydrazones formed in the films were inferred by comparing their absorptions in the infrared and ultraviolet spectra, respectively. It seems that the contents of carbonyl groups formed in the amorphous regions in the high-density polyethylene films by the irradiation were larger than the contents of carbonyl groups formed in the amorphous regions in the low-density polyethylene films. The decreases in contact angles of water on the high-density polyethylene films by the irradiation were larger than the decreases in the contact angles on the low-density polyethylene films. The amounts of 2,4-dinitrophenylhydrazones formed in the irradiated high-density polyethylene films were less than the amounts of 2,4-dinitrophenylhydrazones formed in the irradiated low-density polyethylene films.