Both CD46 and signaling lymphocytic activation molecule (SLAM) have been shown to act as cellular receptors for measles virus (MV). The viruses on throat swabs from nine patients with measles in Japan were titrated on Vero cells stably expressing human SLAM. Samples from all but two patients produced numerous plaques on SLAM-expressing Vero cells, whereas none produced any plaques on Vero cells endogenously expressing CD46. The Edmonston strain of MV, which can use either CD46 or SLAM as a receptor, produced comparable titers on these two types of cells. The results strongly suggest that the viruses in the bodies of measles patients use SLAM but probably not CD46 as a cellular receptor.Measles virus (MV) is an enveloped negative-strand RNA virus of the Morbillivirus genus in the Paramyxoviridae family (4). Measles remains an important cause of childhood mortality, with approximately one million deaths per year worldwide (2), mainly due to secondary infections caused by MV-induced immunosuppression (4). Human CD46 has been shown to be a cellular receptor for vaccine strains of MV, such as the Edmonston strain (3, 10). However, wild-type MV strains that are commonly isolated in marmoset B-cell line B95a or human B-cell lines usually do not use CD46 as a receptor (5-7, 14, 15, 18), although a study has reported that MV strains isolated from and propagated only in human peripheral blood mononuclear cells (PBMCs) use CD46 as a receptor (9). We have recently demonstrated that signaling lymphocytic activation molecule (SLAM; also known as CDw150) is a cellular receptor for MV, including the Edmonston strain, B95a-isolated strains, and PBMC-isolated strains (20). Thus, some MV strains use SLAM but not CD46 as a receptor, and others, such as the Edmonston strain, use either SLAM or CD46. The type of MV strain obtained depends on the cell types used for virus isolation. In this study, we sought to quantitate the proportions of these two types of MV in measles patients.Vero cells are susceptible to the Edmonston strain but not to B95a-isolated MV strains (6, 18). In order to titrate B95a-isolated MV strains on Vero cells, we transfected them with the expression plasmid encoding human SLAM (pCAGhSLAM) (12) and the vector plasmid pCXN2 (11) containing the neomycin resistance (neo) gene; we selected stable clones in the presence of G418. We used the clone expressing the highest level of human SLAM (Vero/hSLAM) in the following experiments.The expression profile of Vero/hSLAM cells stained with anti-human SLAM monoclonal antibody IPO-3 (Kamiya Biomedical) (17) is shown in Fig. 1A. Vero/hSLAM cells were infected with the B95a-isolated KA strain of MV (18-20) at a multiplicity of infection of 0.1. At 24 h after infection, they developed extensive syncytia (Fig. 1B), unlike the parental Vero cells (6, 18). Then, we used Vero and Vero/hSLAM cells for plaque titration of the KA strain. Vero/hSLAM cells developed clear plaques after infection with the KA strain, whereas Vero cells inoculated with the same amount of the virus did no...

We report the observation of two-dimensional plasma filamentary arrays with more than 100 elements generated during breakdown of air at atmospheric pressure by a focused Gaussian beam from a 1.5-MW, 110-GHz gyrotron operating in 3-s pulses. Each element is a plasma filament elongated in the electric field direction and regularly spaced about one-quarter wavelength apart in the plane perpendicular to the electric field. The development of the array is explained as a result of diffraction of the beam around the filaments, leading to the sequential generation of high intensity spots, at which new filaments are created, about a quarter wavelength upstream from each existing filament. Electromagnetic wave simulations corroborate this explanation and show very good correlation to the observed pattern of filaments.

ObjectivesTo determine whether febuxostat with stepwise dose increase is as useful as colchicine prophylaxis in reducing gout flares during the initial introduction of urate-lowering therapy in patients with gout in comparison with febuxostat with no dose titration.MethodsIn this prospective, multicentre, randomised open-label comparative study, patients were randomised to group A (stepwise dose increase of febuxostat from 10 to 40 mg/day), group B (fixed-dose febuxostat 40 mg/day plus colchicine 0.5 mg/day) or group C (fixed-dose febuxostat 40 mg/day) and observed for 12 weeks. Gout flare was defined as non-steroidal anti-inflammatory drug use for gout symptoms.ResultsA total of 255 patients were randomised, and 241 patients were treated. Among the treated patients, gout flares were experienced by 20/96 (20.8%) in group A, 18/95 (18.9%) in group B and 18/50 (36.0%) in group C. The incidence of flare was significantly lower in groups A and B than that in group C (P=0.047 and P=0.024, respectively), although the differences were not significant after correction for multiple comparisons. No significant difference was noted between the incidence of gout flare in groups A and B.ConclusionsOur data suggested that stepwise dose increase of febuxostat and low-dose colchicine prophylaxis effectively reduced gout flares in comparison with fixed-dose febuxostat alone. Stepwise dose increase of febuxostat may be an effective alternative to low-dose colchicine prophylaxis during the introduction of urate-lowering therapy.Trial registration numberUMIN 000008414.

Regular two-dimensional plasma filamentary arrays have been observed in gas breakdown experiments using a pulsed 1.5 MW, 110 GHz gyrotron. The gyrotron Gaussian output beam is focused to an intensity of up to 4 MW/cm2. The plasma filaments develop in an array with a spacing of about one quarter wavelength, elongated in the electric field direction. The array was imaged using photodiodes, a slow camera, which captures the entire breakdown event, and a fast camera with a 6 ns window. These diagnostics demonstrate the sequential development of the array propagating back toward the source. Gases studied included air, nitrogen, SF6, and helium at various pressures. A discrete plasma array structure is observed at high pressure, while a diffuse plasma is observed at lower pressure. The propagation speed of the ionization front for air and nitrogen at atmospheric pressure for 3 MW/cm2 was found to be of the order of 10 km/s.