Search

Background: We investigated the effect of the pretransplant administration of recipient''s blood to donor on rat hepatic allograft survival. Methods: Serum levels of interferon (IFN)-γ were determined after transplantation. Immunocompetent cells from the donor were identified with anti-donor class II MHC (RT1Ba) (OX-76) antibodies. The number of donor-derived CD4+ and CD8+ T cells in hepatic allografts or recipient spleen was determined. Results: LEW rats transplanted with hepatic allografts from ACI rats survived a mean of 11.1±2.1 days. Pretreatment intravenous administration of recipient LEW blood did not prolong the survival of hepatic allografts (10.5±1.7 days). In contrast, pretreatment intraportal administration of recipient LEW blood significantly increased the survival of LEW recipients with ACI livers to 31.7±7.6 days (Table 1). The ratio of ox76+CD4+ or ox76+CD8+ T cell to CD4+ or CD8+ cell was significantly greater (25.6% versus 5.7%, 26.6% versus 6.8%) in hepatic allografts pretreated with pretransplant intraportal administration of LEW recipient blood, rather than those cells in recipient spleen (46.2% versus 34.4%, 63.7% versus 71.4%). Conclusions: Pretransplant intraportal administration of recipient LEW blood to ACI donor rats prolonged the survival of hepatic allografts. This may be associated with the regional graft-versus-host reaction. [Copyright &y& Elsevier]

We have investigated the temperature dependence of unit-cell and structural parameters of ceria (cerium dioxide, CeO2) from room temperature to 1770 K by neutron powder diffraction and the Rietveld method. The unit-cell parameter increases continuously with temperature. It was confirmed that the Debye–Waller factor of oxygen B(O) is larger than that of cerium B(Ce) at any temperature from room temperature to 1770 K. Both B(O) and B(Ce) increase with an increase of temperature. [Copyright &y& Elsevier]

Aims In obesity, infiltration of adipose tissue by proinflammatory immune cells causes chronic low-grade inflammation. We investigated the chemokine profiles of human visceral adipocytes by the reverse transcription polymerase chain reaction and the effect of human neutrophil elastase (HNE) on monocyte chemoattractant protein-1 (MCP-1) mRNA and protein levels. Main methods Human adipocytes were obtained from cryopreserved omental preadipocytes of subjects with a body mass index (BMI) < 30 kg/m 2 or > 30 kg/m 2 and were cultured to assess chemokine production. Key findings Chemokine responses associated with obesity-related inflammation were well preserved in cultured human adipocytes derived from cryopreserved preadipocytes. Visceral adipocytes from subjects with a BMI > 30 kg/m 2 expressed mRNA for MCP-1, regulated on activation, normal T cell expressed and secreted (RANTES), epithelial cell-derived neutrophil-activating peptide-78 (ENA-78), interleukin-8 (IL-8), lymphotactin-β, and fractalkine. Although visceral adipocytes from subjects with a BMI < 30 kg/m 2 also expressed MCP-1, RANTES, ENA-78, and IL-8 mRNA, neither lymphotactin-β nor fraktalkine mRNA was detected. Interestingly, expression of MCP-1 mRNA was decreased significantly after exposure to HNE (85 × 10 3 μM/L), suggesting the induction of nuclear factor-kappa B repressing factor. Significance Adipocytes from subjects with a BMI > 30 kg/m 2 or < 30 kg/m 2 have different chemokine profiles. Only adipocytes from subjects with a BMI > 30 kg/m 2 express lymphotactin-β and fractalkine mRNA. Differential chemokine profiles of visceral adipocytes contribute to infiltration of adipose tissue by adaptive immune cells. Neutrophil activation is involved in induction of nuclear factor-kappa B repressing factor, resulting in regulation of immune cell trafficking. [ABSTRACT FROM AUTHOR]

Abstract: Using a transportable 3He spin filter neutron polariser, we have constructed a polarised thermal neutron diffraction (PND) instrument on a powder neutron diffractometer. To minimise the inhomogeneity of the magnetic fields around the 3He spin filter, an optimised compact non-adiabatic two-coil spin flipper for the PND instrument was developed. Magnetic field criteria were discussed for the design of the flipper. Using the PND instrument with the flipper, we succeeded in observing a difference in the magnetic field dependence of the deposited ferromagnetic phases in nanocomposite materials. [Copyright &y& Elsevier]

Abstract: We measured neutron diffraction profiles of powdered KOD-doped D2O ice to investigate the formation and growth of ice XI, a deuterium-ordered phase of ice, from ice Ih, a disordered phase. During the measurements, the ice was annealed at 57K for about 17h, and then warmed up and kept at 68K for about 55h, which are below the transition temperature . The diffraction profiles for the doped ice at 57K did not change with time and were close to those for ice Ih with the deuterium-disordered arrangement. However, when the temperature increased from 57 to 68K, the diffraction profiles changed. We carried out the Rietveld analysis with the parameters for a two-phase model to obtain the structural evidence of the appearance and the growth of ice XI. The analysis provided evidence of ice XI as space group Cmc21 at 68K. The temporal increase of the mass fraction of ice XI showed that nucleation of ice XI began just after warming up to 68K. Then, ice XI grew for several days in the doped ice. This study provides first structural observations of the growth of ice XI. [Copyright &y& Elsevier]

Magnetic and calorimetric properties of Ba3TbRu2O9 are reported. Neutron diffraction measurements show that this compound adopts the 6H-perovskite structure with space group P63/mmc, in which the cation sites within the face-sharing octahedra are occupied by Ru ions and those within the corner-sharing octahedra are occupied by Tb ions. The magnetic susceptibility and specific heat measurements indicate that an antiferromagnetic transition occurred at 9.5 K. Neutron diffraction data collected at 2 K show that Ba3TbRu2O9 has a long-range antiferromagnetic ordering of Tb4+ ions. The moments of Tb4+ ions order ferromagnetically in the c planes, and these ferromagnetic planes are stacked antiferromagnetically along the c-axis. The direction of ordered moments is parallel to the c-axis. The ordered magnetic moment of Tb4+ ions is 6.84(4) μB. [Copyright &y& Elsevier]

We have studied pressure effects on the magnetic and electronic nature of layered oxysulfide Sr2Cu2CoO2S2 which crystallizes in an unusual intergrowth structure. The derivative permeability (dμ/dT) curves have a kink near Tt at which the antiferromagnetic nature is changed from 2D to 3D; Tt extremely rises with increasing pressure (dTt/dP=13.5 K/kbar), indicating that 3D antiferromagnetic state is more stable under pressure. The Tt in the dμ/dT curves correspond to the bending point of the resistivity, and above Tt the nearest-neighbor hopping conduction occurs. These features would be discussed from the viewpoint of the coupled nature of charge carriers and 2D antiferromagnetic spin ordering. [Copyright &y& Elsevier]