Preparation of LiCoO2 by Molten Salts on Li0.29La0.57TiO3 Solid Electrolyte and Electrochemical Performances of the All-solid-state Li Secondary Battery

An LiCoO2 (LCO) phase is prepared on a perovskite type Li0.29La0.57TiO3 (LLTO) solid electrolyte by heating mixed lithium salts of LiNO3 and LiCl with Co(NO3)2·6H2O at 700 °C for 1 h. The resultant LCO is evaluated as a positive electrode in an all-solid-state Li secondary battery. Liquid-phase sintering using molten salts has been effective for the formation of a favorable interface between oxides in which lithium ions migrate electrochemically with reversibility. The fracture surface revealed by field emission scanning electron microscopy observation shows that the microscopic texture of the LCO consists of a dense 1 to 2 µm thick layer closely attached to the solid electrolyte over a wide area, as well as LCO spherical particles with sizes of several micrometers. The former growth has superior electrochemical activity compared to the latter. Additionally, a preferential growth plane of the LCO on LLTO is analyzed by transmission electron microscopy and the process of formation with heating is described

Expansion of a CD28-Intermediate Subset among CD8 T Cells in Patients with Infectious Mononucleosis

Infectious mononucleosis (IM) is an acute sporadic infection that usually affects young adults, and during infection a massive expansion of CD8 T cells is generally considered to occur. However, CD28 expression of the expanded cells has not been characterized. When peripheral blood mononuclear cells of acute IM (AIM) patients were analyzed by flow cytometry, a continuous spectrum of CD28 intensity ranging from negative to high, which could be separated into CD28 negative, intermediate (int), and positive, was seen for CD8 T cells. We studied 26 IM patients who were diagnosed on the basis of standard methods and found that all patients had the continuous CD28 spectrum. CD28 is a costimulatory molecule on T cells, and its expression is associated with the subdivision of CD8 cells into cytotoxic (CD28-positive) and suppressor (CD28-negative) T cells. After 24 h of ex vivo culturing, however, the continuous spectrum was found to consist of only CD28-positive and CD28-negative CD8 T cells, because the CD28-int cells had disappeared due to apoptosis. The CD28-int T cells have several cytotoxic functions, suggesting that CD28-int T cells are effectors. Examination of other costimulatory markers in AIM patients showed that CD80 and CD152 were not affected. In patients with other viral infections, such as measles or rubella, however, the continuous spectrum was not detected. These results suggest that there is an unusual CD28 expression pattern in patients with AIM, namely, the presence of a functional CD28-int subset among CD8 T cells. These findings are of special importance for clarifying the defense mechanism against Epstein-Barr virus infection, and the role of CD28 molecules in humans and should also be helpful for the diagnosis of AIM

Botulinum ADP-ribosyltransferase activity as affected by detergents and phospholipids

AbstractGTP-binding proteins with Mr values of 22 000 and 25 000 in bovine brain cytosol were ADP-ribosylated by an exoenzyme (termed C3) purified from Clostridium botulinum type C. The rate of C3-catalyzed ADP-ribosylation of the partially purified substrates was extremely low by itself, but was increased enormously when a protein factor(s) obtained from the cytosol was simultaneously added. The rate of the C3-catalyzed reaction was also stimulated by the addition of certain types of detergents or phospholipids even in the absence of the protein factors. The ADP-ribosylation appeared to be enhanced to an extent more than the additive effect of either the protein factors or the detergents (and phospholipids). Thus, ADP-ribosylation catalyzed by botulinum C3 enzyme was affected not only by cytoplasmic protein factors but also by detergents or phospholipids in manners different from each other