Infection with hepatitis G virus and its strain variant, the GB agent (GBV-C), among blood donors in Japan

Much of the morbidity and mortality seen in cystic fibrosis (CF) is related to chronic infection of the respiratory tract with Pseudomonas aeruginosa. Some studies have attributed the strong relationship between CF and Pseudomonas colonization to the presence of increased numbers of specific cell-surface receptors, although other work suggests that this relates to the presence of mucus. Several groups are now assessing the use of gene transfer as a novel form of treatment for CF. We have examined whether P. aeruginosa binding to freshly obtained CF respiratory epithelial cells is increased, and have studied the effects of transfer of the CF transmembrane conductance regulator (CFTR) gene on this attachment. Binding of P. aeruginosa to noncultured nasal epithelial cells from both CF patients (n = 31) and healthy controls (n = 15) was studied with scanning electron microscopy. Binding was also assessed for CF cells following transfection with CFTR/liposome complexes. Epifluorescence microscopy was used to assess the effects of gene transfer on chloride fluxes. Adherence of P. aeruginosa directly to the cell surface of CF airway epithelium was significantly (P < 0.001) increased over that in non-CF controls. Liposome-mediated CFTR gene transfer resulted in a significant (P < 0.01) reduction in the numbers of bacteria bound to ciliated epithelial cells. Fluorescence microscopy confirmed correction of the basic chloride defect. Thus, in CF, the absence of normal CFTR results in increased binding of P. aeruginosa to respiratory epithelial cells. This abnormality can be corrected in vitro by restoration of CFTR function. This has important implications both for the pathogenesis of CF and for the future application and assessment of gene therapy for this disease.     

Gibbs Energy Change of Carbothermal Nitridation Reaction of Al2O3 to Form AlN and Reassessment of Thermochemical Properties of AlN

The experimental method for the high-temperature reaction equilibria in the AlN-Al₂O₃ system has been established. The equilibrium N₂-CO gas compositions coexisting with AlN- Al₂O₃-graphite have been successfully measured by quadrupole mass spectrometry and gas chromatography. From the obtained results, the standard Gibbs energy change of the forming reaction of AlN by carbothermal nitridation is determined at temperatures ranging from 1723 to 1899 K:
From the obtained result, the standard Gibbs energy of formation of AlN and the third-law enthalpy of formation of AlN at 298.15 K are derived as
The disagreement between the present results and values in the NIST–JANAF thermodynamic table is discussed.     

Structural,Thermal and Magnetic Properties of Thin Metal Films and Adsorbate–Substrate Systems Studied by XAFS and XMCD

Thin metal films often exhibit interesting properties that are essentially different from the bulk ones. XAFS (X-ray absorption fine structure) and XMCD (X-ray magnetic circular dichroism) techniques are quite suitable to investigate structural, thermal and magnetic properties of thin metal films. In this proceeding, we will present following two topics concerning structural and magnetic properties of adsorbates on thin metal films. The first one is the adsorption geometry of SO₂ on a 1-monolayer (ML) Pd thin film grown on a Ni(111) single crystal. It was found by S K-edge XAFS that SO₂ is lying flat on 1-ML Pd/Ni(111). This result is not similar to the bulk Pd surface but to the bulk Ni one. This finding indicates significant modification of the electronic structure of the 1-ML Pd film compared to the bulk one. The second topic is the magnetic moment induced on CO adsorbed on Ni epitaxial films grown on Cu(001). The O K-edge XMCD results revealed that in the perpendicularly magnetized 10-ML Ni film the orbital moment of CO is parallel to the substrate Ni magnetization, while it is antiparallel in the in-planar magnetized 6-ML and thick (>100 ML) films. The origin of the induced orbital moment at CO is discussed.     

Sudden cardiac tamponade due to hemorrhagic myocarditis after preconditioning marrow transplantation with cyclophosphamide in a patient with aplastic anemia

Matrix metalloproteinases have been shown to be important in tumour invasion and metastasis, and the use of matrix metalloproteinase inhibitors in animal models has suggested that these agents may be useful in the control of malignant disease. This article reports the results of an early clinical trial of batimastat, one of the first generation of metalloproteinase inhibitors, in patients with malignant ascites. The drug was well absorbed via the intraperitoneal route and associated with few side-effects. Furthermore, a response to treatment was seen in about half the evaluable patients with advanced malignant disease. The results suggest that further research on the use of matrix metalloproteinase inhibitors in patients with malignant disease is worthwhile.     

Marangoni flow at the gas/melt interface of steel

Direct observation with a scanning laser microscope was made to determine the direction and velocity of surface flow of steel melt in the vicinity of the solid/melt (S/M) interface. During solidification, a fast solutal Marangoni flow moving away from the S/M interface was confirmed to exist on steel melts containing oxygen and sulfur of 10 to 105 ppm. Even in such a low range of oxygen and sulfur content, the solutal Marangoni flow can be very fast, carrying inclusion particles up to the free surface along the S/M interface. During heating and holding, however, a thermal Marangoni flow combined with convective flow generated a reverse flow directed toward the S/M interface. These features have important relevance to inclusion entrainment and solute segregation during the solidification of steel. This article is based on a presentation given in the Mills Symposium entitled “Metals, Slags, Glasses: High Temperature Properties & Phenomena,” which took place at The Institute of Materials in London, England, on August 22–23, 2002.     

Long wavelength waveguide multiple quantum well optical modulators

The first measurements of large anisotropic modulation of long-wavelength light with a large on/off ratio and low driving voltage propagating along the plane of InGaAs/InAlAs multiple quantum well (MQW) structures grown by molecular beam epitaxy (MBE) are reported. Photocurrent response and optical modulation of waveguide pin diodes is measured for incident light polarization parallel and perpendicular to the MQW layers emitting from a color center laser. The incident-light power and wavelength dependence of on/off ratio are also determined.     

Hydrogen production by combining two types of photosynthetic bacteria with different characteristics

The double-layer photobioreactor using two types of photosynthetic bacteria, Rhodobacter sphaeroides RV and its reduced-pigment mutant, MTP4, was developed for efficient hydrogen production. The two types of bacteria had different characteristics on light energy, hydrogen production rate and conversion efficiency. MTP4 produced hydrogen more efficiently under high light conditions and RV did so under low light conditions. Illuminated light toward the surface of a photobioreactor quasi-exponentially declines as it penetrates into the reactor. When two types of bacteria were placed using the developed reactor according to this light distribution, the hydrogen production rate reached 3.64 l/m²/h at a light intensity of 500 W/m² in 24 h and the conversion efficiency of light energy to hydrogen was 2.18%. These values were 33% higher than those of only using RV. The low light in the deep part of the reactor was utilized efficiently, resulting in a higher hydrogen production rate.     

Efficient hydrogen production using a multi-layered photobioreactor and a photosynthetic bacterium mutant with reduced pigment

A multi-layered photobioreactor (MLPR), where the light paths were formed by the localization of bacterial cells, was constructed for efficient hydrogen production. The performance was investigated under several conditions in order to clarify the effect of this reactor on hydrogen production. An analysis of the hydrogen production profile showed that the MPLR utilizes both the light that directly illuminates its surface and the light induced and diffused from its light paths for hydrogen production. It was also found that the hydrogen productivity in the MLPR was more than twice that in a plate-type reactor. When a photosynthetic bacterium mutant with reduced pigment, MTP4, was used, the maximum hydrogen production rate reached 2.0 l/m² h, which was 38% higher than that of a conventional plate-type reactor. The synergistic effect of the improvement in the reactor and the modification of the bacteria was brought about by the combination of the MLPR and MTP4, and resulted in an improvement in the hydrogen production.