The careful control of actinide distribution between 30% tributylphosphate (TBP) in organic diluent and nitric acid is vital to the successful operation of nuclear fuel reprocessing plants. Uranium (VI) and tetravalent actinides are extracted into the organic phase as the nitrate complexes UO 2 (NO 3 ) 2 (TBP) 2 and An(NO 3 ) 4 (TBP) 2 respectively. The presence of dibutylphosphate (HDBP), a tributylphosphate decomposition product, affects this distribution due to the formation of strong, organic soluble, complexes between the phosphate and the actinide ions. This paper describes the investigation of U(VI), U(IV), Np(IV) and Pu(IV) complexation with HDBP in 30% TBP/organic diluent solutions. The distribution of U(VI) between nitric acid and 30% TBP/organic diluent solutions containing HDBP and subsequent analysis of the organic phases by 31 P nuclear magnetic resonance spectroscopy, absorption spectroscopy and extended X-ray absorption spectroscopy indicates that U(VI) can form a range of complexes with HDBP. At comparatively high HNO 3 loading in the organic phase, HDBP can displace TBP groups to form either UO 2 (NO 3 ) 2 (HDBP)(TBP) or UO 2 (NO 3 ) 2 (HDBP) 2 . At lower HNO 3 loadings HDBP can also deprotonate and act as a chelate ligand displacing nitrates to form either UO 2 (DBP) 2 -

We studied the effect of preliminary loading of peritoneal macrophages with silicium dioxide on in vitro viability, phagocytosis of BCG strain mycobacteria, and the capability to destroy the phagocytosed mycobacterium tuberculosis. It was shown that preliminary loading of macrophages with silicium dioxide did not reduce their viability and stimulated phagocytosis of BCG strain mycobacteria, but reduced their antibacterial activity.

We studied the dependence of in vitro dextran biocompatibility on the method of oxidation of 35-kDa dextran. The biocompatibility of dextran oxidized with potassium permanganate was higher compared to that obtained by radiochemical oxidation. It was related to the formation of peroxide compounds during radiochemical oxidation.

We studied in vitro morphological and functional properties of macrophages associated with their M1 and M2 polarization in different mononuclear phagocyte compartments during BCG-induced granuloma formation, namely expression patterns of cytokines IL-1α, GM-CSF, TNF-α, and clusters of differentiation CD36 and CD16/32. We showed the mosaic pattern of macrophage polarization in BCG granulomatosis manifested by simultaneous formation of different macrophage subpopulations with M1 and M2 phenotypes in the population of mononuclear phagocytes of BCG granulomas and various compartments of the mononuclear phagocyte system. These data clarify the role of the functional polarization of macrophages in the pathogenesis of tuberculosis infection.

The spleens were isolated from mice at different times after BCG infection and BCG granulomas were explanted and cultured in vitro. Cell migration, chemoattractant potential, and expression of TNF-α and granulocyte-macrophage CSF (GM-CSF) by macrophages migrated from granulomas were evaluated in granulomas. The number of macrophages able to migrate; migrating out of granulomas, expressing TNF-α and GM-CSF decreased with increasing the time after infection. The number of cells in "dissociating" granulomas correlates with the number of macrophages containing live BCG mycobacteria in the cytoplasm.