Clonal origin of Epstein-Barr virus-infected T/NK-cell subpopulations in chronic active Epstein-Barr virus infection

Clonal expansion of Epstein-Barr virus (EBV) infected B-cells occasionally occurs in immunocompromized subjects. EBV-infected T/natural killer (NK)-cells proliferate in patients with chronic active EBV infection (CAEBV) that is a rare mononucleosis syndrome. It is classified into either T-cell type or NK-cell type according to the primary target of infection, while the pathogenesis remains unclear. To search the clonal origin of EBV-infected T/NK-cells, virus distribution and clonotype were assessed by using highly purified cell fractions obtained from 6 patients. Patient 1 had a monoclonal proliferation of EBV-infected T-cell receptor Vδ2/Vγ9-expressing cells, and carried lower copy number of EBV in αβT-cells. Patients 2 and 3 had a clonal expansion of EBV-infected CD4+T-cells, and lower EBV load in CD56+cells. Patients 4, 5 and 6 had an expansion of CD56+cells with higher EBV load than CD3+cells. EBV-terminal repeats were determined as clonal bands in the minor targeted populations of 5 patients. The size of terminal repeats indicated the same clonotype in minor subsets as in major subsets of 4 patients. However, EBV was not detected in bone marrow-derived lineage negative CD34+cells of patients. These results suggested that EBV could infect T/NK-cells at differentiation stage, but spared bone marrow CD34+hematopoietic stem cells in CAEBV patients

A Fundamental Study on Influence of Concurrently Presented Visual Stimulus Upon Loudness Perception

As a basic study on the influence of the dynamic properties of the audio-visual stimuli upon interaction between audition and vision, the effect of the simple movement involved in the visual stimulus on the loudness perception of the audio stimulus was investigated via psychophysical experiment. In this experiment, the visual stimulus given to subjects along with the audio stimulus is a bar appeared on a display, one side of which is flexibly expanding and contracting. The loudness of the audio stimulus with such a visual effect concurrently presented was rated as an absolute numerical value by using the Magnitude Estimation method. The reference of the bar length is determined so as to correspond to the Zwicker's loudness calculated for the given audio stimulus. As a result, the visual stimulus did not affect the loudness perception, when the bar was presented with its length same as the reference. On the other hand, the rating of the loudness for the same audio stimulus was significantly increased when the bar length was longer than the reference. This indicates that the change in the correspondence between the audio and the visual stimuli affect the loudness perception

Enhanced Photoanodic Output at an Organic p/n Bilayer in the Water Phase by Means of the Formation of Whiskered Phthalocyanine

The photoelectrode characteristics of an organic p/n bilayer in the water phase were studied with respect to film; 3,4,9,10-perylenetetracarboxylic-bisbenzimidazole (PTCBI, an n-type semiconductor) was used in combination with 29<i>H</i>,31<i>H</i>-phthalocyanine (H₂Pc, a p-type semiconductor). When H₂Pc was vapor-deposited on top of the PTCBI layer on a heated substrate (cf. degree of pressure, ca. 5.0 × 10^–4 Pa; temperature at the substrate, 120°C), a transmission electron microscopic image showed an enhanced contact area of the p/n interface in comparison with that prepared at r.t., due to the formation of a whisker H₂Pc. The PTCBI/H₂Pc bilayer can work as a photoanode along with photophysical events in its interior. The rate-limiting charge transfer at the H₂Pc/water interface was kinetically analyzed assuming the Langmuir adsorption equilibrium at that interface. Kinetic analysis demonstrated that the increased contact area can successfully lead to efficient photoinduced carrier generation; particularly, when a thick whisker of H₂Pc was formed, the magnitude of the oxidation kinetics at the H₂Pc/water interface was approximately 2.5 times higher than that without thermal treatment