Interleukin-12 preserves the graft-versus-leukemia effect of allogeneic CD8 T cells while inhibiting CD4-dependent graft-versus-host disease in mice

We have recently demonstrated that a single injection of 4,900 IU of interleukin-12 (IL-12) on the day of bone marrow transplantation (BMT) markedly inhibits acute graft-versus-host disease (GVHD) in a fully major histocompatibility complex plus minor antigen-mismatched BMT model (A/J --> B10, H-2(a) --> H-2(b)), in which donor CD4(+) T cells are required for the induction of acute GVHD. We show here that donor CD8-dependent graft-versus-leukemia (GVL) effects against EL4 (H-2(b)) leukemia/lymphoma can be preserved while GVHD is inhibited by IL-12 in this model. In mice in which IL-12 mediated a significant protective effect against GVHD, marked GVL effects of allogeneic T cells against EL4 were observed. GVL effects against EL4 depended on CD8-mediated alloreactivity, protection was not observed in recipients of either syngeneic (B10) or CD8-depleted allogeneic spleen cells. Furthermore, we analyzed IL-12-treated recipients of EL4 and A/J spleen cells which survived for more than 100 days. No EL4 cells were detected in these mice by flow cytometry, tissue culture, adoptive transfer, necropsies, or histologic examination. Both GVL effects and the inhibitory effect of IL-12 on GVHD were diminished by neutralizing anti-interferon-gamma (IFN-gamma) monoclonal antibody. This study demonstrates that IL-12-induced IFN-gamma production plays a role in the protective effect of IL-12 against GVHD. Furthermore, IFN-gamma is involved in the GVL effect against EL4 leukemia, demonstrating that protection from CD4-mediated GVHD and CD8-dependent anti-leukemic activity can be provided by a single cytokine, IFN-gamma. These observations may provide the basis for a new approach to inhibiting GVHD while preserving GVL effects of alloreactivity.     

The duplex nature of anodic barrier films formed on aluminium in aqueous borate and borate-glycol solutions

Direct transmission electron microscopy of ultramicrotomed sections of aluminium and its anodic films formed in borate-containing environments, and subsequent electron-beam-induced crystallization, has been employed to gain further insight into the development of contaminated Al₂O₃ during anodizing. For film formation in ammonium pentaborate solution, it is suggested that borate species incorporated into the Al₂O₃ film material are immobile during anodizing. Conversely, the borate species incorporated into the film material during anodizing in the ammonium pentaborate-ethylene glycol electrolyte are apparently mobile in the field. Thus, on a direct interpretation basis, the apparent aluminium transport number can be assessed from the extents of the differently textured regions apparent after electron-beam-induced crystallization in which the borate species are immobile.     

Thermodynamics of the Ti-H system

Hydrogen gas has been equilibrated with the hydrogen dissolved in titanium. The equilibrium pressure (<10 MPa) of the gas and the hydrogen concentration (40 ∼ 70 mol pct) in titanium have been measured at 576 to 980 K by Sieverts' method. A Gibbs-Duhem integration has been made to obtain the thermodynamic activity of titanium and the formation properties of the “TiH₂” phase. Interaction energies between neighboring atoms in the hydride have been evaluated by applying a quasi-chemical model of statistical mechanics.     

A self-aligned retrograde twin-well structure with buried p+-layer

The retrograde twin wells and buried p⁺ layer are fabricated by a single lithographic step using high-energy ion implantation. The retrograde n-well is self-aligned to the retrograde p-well regions. This simple process allows a scalable CMOS structure for the very tight n⁺-to-p⁺ spacing. It provides latch-up immunity at the 1.5-μm n⁺-to-p⁺ spacing and good isolation characteristics without additional n- and p-channel stops     

Nature of luminescence during galvanostatic anodizing of high purity aluminium

Galvanoluminescence of high purity aluminium was found to have two fundamental origins: one was the luminescence associated with scintillation or with some concommitant side reactions, taking place at the flaws; the other was the luminescence associated with anions included in the films during anodization. The former appeared to be the origin of the luminescence in inorganic electrolytes such as ammonium borate, borax, borax plus boric acid etc; and the latter appeared to be responsible for the luminescense in organic acids and their salts, such as oxalic, citric, tartaric and succinic acids and ammonium tartrate.     

Hydrothermal synthesis of fibrous lead titanate powders

A fibrous lead titanate (PbTiO₃) powder with light-yellow colour has been prepared by hydrothermal synthesis. The influences of Pb/Ti ratio (0.3 to 1.0) in the mixture and reaction time on the formation of fibrous PbTiO₃ under hydrothermal conditions have been investigated. The preferable conditions for preparing fibrous perovskite-type PbTiO₃ from fibrous potassium titanate are that the Pb/Ti ratio is 1.0, reaction temperature 150 °C and time 72 h. The particles of fibrous powder of perovskite type are usually less than 2 m in diameter and more than 50 m in length. The fibrous morphology is essentially unchanged up to about 650 °C, but it disappeared after heating to 1000 °C.     

Origin of Ordering Coupled Tweed Microstructures in Alloys with Large Atomic Size Factors

A theoretical study is developed on the evolution and mechanism of an ordering coupled phase separation, and on the origin of a resultant tweed microstructure. It is found that long-range elastic interaction among atoms with different atomic sizes plays a key role in the phase sep aration, and that the evolution of the phase separation is very similar to that Of conventional spinodal decomposition except that the separation is dependent on an elastic interaction order ing (EIO). This "EIO coupled spinodal decomposition" is shown to exhibit a periodical or tweed microstructure being accompanied by an EIO. It is also found that a large atomic size factor yields a large positive contribution of EIO to spinodal decomposition. Generally it is thermodynamically and kinetically favorable for the EIO to precede the onset of spinodal decomposition,though the former is not separable from the latter as a whole. We suggest that an initially disordered solid solution undergoes an EIO first, and then the partially ordered solid solution starts to decompose via a spinodal mechanism. Solute-enriched regions increase their degree of order along with an increase in solute content, and solute-depleted regions decrease their degree of order together with a decrease of solute content. The final microstructure is characterized by a periodical array of highly ordered solute-enriched regions and nearly disordered solute-depleted regions. The notion of EIO coupled spinodal decomposition is in general agreement with the transformation behaviour of a large number of alloy systems.     

Elastic Energy and Elastic Interaction Ordering of Binary Solid Solutions

A theory in the framework of continuum elasticity has been developed to calculate the totalcontribution of "atomic size effect" or "strain energy effect" to free energy of binary solidsolutions. It is found that elastic free energy consists of two parts f elastic self energy (ESE),and elastic interaction energy(EIE). The former is a function of composition alone, the latter isalso a function of atomic configuration. Minimization of total elastic free energy with respect toatomic arrangement resuIts in an ordered arrangement of atoms, which is caIIed elastic interactionordering (EIO), as it originates from elastic interaction among atoms. EIO is a kind of localordering within a "characteristic range", and it is found to be important in determining the Stateof solid solutions and structures of superlattices. The present theory also gives good explanationto the coexistence of ordering and decomposition which can not be understood in conventionaltheories.     

Barium titanate fabricated from fur-fibres

Long-fibrous barium titanate (BaTiO₃) particles were prepared by a hydrothermal reaction of potassium titanate hydrate (2K₂O·11TiO₂·3H₂O) and barium hydroxide (Ba(OH)₂). Effects of preparation conditions on crystal structure and powder morphology were examined. Fur-fibres of K₂O·4TiO₂, 1–10 mm long and 1–100 m in diameter, were obtained by heating a mixture of K₂CO₃ and TiO₂ powders at 1000 C for 100 h. Keeping the fur-fibres in ion-exchanged water for 4 days gave fur-fibres of 2K₂O·11TiO₂·3H₂O). Long-fibrous BaTiO₃, with fibres 100m–1mm long and 1–10 m in diameter, was obtained by a hydrothermal reaction of the hydrate and Ba(OH)₂ (Ba/Ti ratio of 1) at 150 C for 24 h. As-prepared long-fibrous BaTiO₃ was composed of fine crystallites (average size about 270 nm) of cubic phase. The cubic phase and morphology of fur-fibres were maintained up to 1250 C, but heat treatment at 1300 C brought about a growth of crystallites to a few micrometers and a phase transformation to tetragonal phase. It was found that the hydrothermal reaction was effective in producing crystalline BaTiO₃ powder at a low temperature of 150 C.