PP069. The expressions of B7-H1 and B7-H4 co-stimulatory molecules on myeloid and lymphoid dendritic cells in pre-eclampsia and normal pregnancy. The expressions of B7-H1 and B7-H4 co-stimulatory moleculeson myeloid and lymphoid dendritic cells in pre-eclampsia and normal pregnancy.

INTRODUCTION: Pre-eclampsia (PE) is a common obstetric syndrome affecting about 5-10% of pregnant women. The syndrome is a leading cause of maternal and fetal morbidity and mortality, even in developed world. The etiology and pathogenesis of this syndrome are not fully understood. There are many studies describing alterations in the innate and adaptive immune system which may have an influence on the onset of this disorder. It was suggested that activation of cell-mediated immunity may play the key role in the etiology of pre-eclampsia. OBJECTIVES: The purpose of our study was to estimate the expressions of B7-H1 and B7-H4 costimulatory molecules on myeloid and lymphoid DCs (CD1c(+), BDCA-2(+)) in the peripheral blood of patients with pre-eclampsia and normal pregnant women in the third trimesters of physiological pregnancy. METHODS: Thirty three patients with pre-eclampsia and 26 normal pregnant women were included in the study. Dendritic cells were isolated from peripheral blood, stained with monoclonal antibodies against blood dendritic cell antigens and B7-H1 and B7-H4 molecules and estimated using flow cytometry. RESULTS: The expressions of B7-H1 molecule on CD1c(+) myeloid DCs and B7-H4 molecule on BDCA-2(+) lymphoid DCs did not differ in pre-eclampsia and healthy third trimester pregnant women. The expressions of B7-H4 molecule on CD1c(+) myeloid DCs and B7-H1 molecule on BDCA-2(+) lymphoid DCs were significantly higher in peripheral blood of patients with pre-eclampsia in comparison with the control group. CONCLUSION: It seems possible that higher expressions of B7-H4 molecule on CD1c(+) myeloid DCs and B7-H1 molecule on lymphoid BDCA-2(+) DCs in pre-eclampsia may be the tolerogenic mechanism secondary to the pro-inflammatory response which is observed in this syndrome.

Phonon mechanism of the magnetostructural phase transition in MnAs.

Density functional theory was used to study structural and dynamical changes related to the magnetostructural phase transition in MnAs. The soft mode inducing the transition from the high-symmetry hexagonal to the low-symmetry orthorhombic phase was revealed. A giant coupling between the soft mode and magnetic moments was found and its crucial role in the magnetostructural transition was established. The estimated phonon contribution to the total entropy change has the opposite sign to the magnetic entropy change.

Vibrational properties of alpha- and sigma-phase Fe-Cr alloy.

Experimental and theoretical studies, of the Fe-partial phonon density of states (PDOS) for Fe52.5Cr47.5 alloy having alpha and sigma phases were carried out. The former using the nuclear resonant inelastic x-ray scattering method, and the latter with the direct one. Characteristic features of PDOS, which distinguish one phase from the other, were revealed and successfully reproduced by the theory. Data pertinent to the dynamics such as the Lamb-Mössbauer factor, f, the kinetic energy per atom, E(k), and the mean force constant, D, were directly derived, while vibrational specific heat at constant volume, C(V), and vibrational entropy, S were calculated using the Fe partial PDOS. Based on the values of f and C(V), we determined Debye temperatures, Theta(D). An excellent agreement for some quantities derived from experiment and first-principles theory, like C(V) and quite good ones for others like D and S were obtained.

DFT study of structure stability and elasticity of wadsleyite II.

The structure and stability properties of wadsleyite II as the new phase of Mg(2)SiO(4) has been studied at high pressure by the DFT method. The pressure range corresponds to the transition zone in the Earth. At zero pressure the calculated lattice parameters of the wadsleyite II structure are a=5.749 Å, b=28.791 Å and c=8.289 Å with the density ρ=3406 kg m(-3). The third order Birch-Murnaghan equation of state has been determined for the structure with isothermal bulk moduli K(T)=160.1 GPa and K(T)'=4.3 at a pressure range up to 50 GPa. The elasticity tensor coefficients C(ij)(P), as well as the compressional and shear wave velocities and their pressure derivatives, have been calculated using the deformation method at a range of pressures up to 25 GPa. The results agree with the experimental data and structure properties of the wadsleyite II model. The properties of the wadsleyite II phase are very close to the wadsleyite phase.

The expression of B7-H1 and B7-H4 molecules on immature myeloid and lymphoid dendritic cells in cord blood of healthy neonates.

The aim of our study was to estimate both B7-H1 and B7-H4 molecules on immature myeloid and lymphoid dendritic cells in umbilical cord blood of healthy neonates in comparison with peripheral blood of healthy adults. Thirty nine healthy full-term neonates from physiological single pregnancies and 27 healthy adults were included in the study. The expression of B7-H1 and B7-H4 was revealed using the immunofluorescence method. Statistical analysis was performed using a non-parametric test (Mann-Whitney U-Test). The percentages of BDCA-1+ dendritic cells with B7-H1 and B7-H4 expressions were significantly higher in peripheral blood of healthy adults (p<0.00003). It was either observed that the percentage of BDCA-2+ dendritic cells with the expression of B7-H4 molecules was significantly higher in peripheral blood of healthy adults in comparison with umbilical cord blood (p<0.02). Decreased percentages of dendritic cells and co-stimulatory molecules indicate that neonates have immature immune system. Depletion of co-stimulatory B7-H1 and B7-H4 molecules enable appropriate development of immune response.

Free-energy calculations for the cubic ZrO2 crystal as an example of a system with a soft mode.

We calculate the free energy for a crystalline ZrO(2) with a soft mode by the first-principles method, using the double-well energy-displacement relation. The soft-mode branch is considered as an ensemble of independent anharmonic oscillators of the parabola-plus-Gaussian or of the 2-4 polynomial forms. The anharmonic contributions are included to reproduce the cubic-to-tetragonal phase transition, however, it appears that the cubic phase does not become the most stable within the framework of the independent oscillators approach.

Lattice vibrations in cubic, tetragonal, and monoclinic phases of ZrO2.

First principles calculations of the phonon dispersion relations and the phonon density of states for three zero-pressure zirconia phases are presented. The phonon dispersion relations of the tetragonal and monoclinic phases do not exhibit the imaginary frequencies, contrary to the cubic phase for which the imaginary soft mode is seen. For tetragonal and monoclinic phases the free energies versus temperature are calculated in harmonic approximation. They cross at 1560 K indicating the phase transition.