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In the present work Mg-exchanged zeolit and silicon carbide were used as starting materials for obtaining cordierite/SiC composite ceramics with weight ratio 30:70 and 50:50. Behavior of composite ceramics after thermal shock treatments was investigated. Thermal shock of the samples was measured using standard laboratory procedure, water quench test (JUS.B.D8.319.). Level of surface deterioration before and during quenching was monitored by image analysis. Ultrasonic measurements were used as nondestructive quantification of thermal shock damage in refractory specimens. When refractory samples are subjected to the rapid temperature changes crack nucleation and propagation occurs resulting in loss of strength and materials degradation. The formation of cracks decreases the density and elastic properties of material. Therefore measuring these properties can directly monitor the development of thermal shock damage level. Dynamic Young modulus of elasticity and strength degradation were calculated using measured values of ultrasonic velocities obtained by ultrasonic measurements. Level of degradation of the samples was monitored before and during testing using Image Pro Plus program for image analysis. The capability of ultrasonic velocity technique and image analysis for simple, and reliable nondestructive methods of characterization are presented in this investigation. It was found that both composite materials exhibit good thermal shock resistance.

In this paper composite material made from silicium carbide and cordierite was used in experiments. Behavior of the material in conditions of rapid temperature changes was investigated. Modified water quench test was applied to determine thermal stability behavior of the samples. Image analysis was used to monitored level of surface deterioration before and during quenching. Ultrasonic measurements were used for determination of dynamic Young modulus of elasticity and strength degradation during quenching. Obtained results are used for analysis of the behavior of the samples in conditions of rapid temperature changes and method for the improvement of the thermal stability behavior.

Pentoxifylline (PTX) is a drug used for the treatment of vascular disorders, but it also has a positive therapeutic effect in experimental models of some autoimmune diseases. In this work, we studied the effect of PTX on human monocyte-derived dendritic cells (MDDCs). Immature MDDCs were generated in vitro from monocytes in the presence of recombinant human granulocyte macrophage-colony stimulating factor (rhGM-CSF) and recombinant human interleukin-4 (rhIL-4), while mature MDDCs were obtained by cultivation of immature MDDCs with lipopolysaccharide (LPS). PTX (200 mu g/ml) was added at the beginning of cell cultivation. We found that PTX significantly impaired differentiation and function of immature NIDDCs, as judged by the reduced allostimulatory activity of these cells on allogeneic T cells and down-regulation of costimulatory and adhesion molecules, such as CD86, CD40 and CD54. The maturation of MDDCs in the presence of PTX and LPS was characterized by the decreased expression of maturation marker CD83 and costimulatory molecule CD86, as well as lower stimulation of alloreactive T cells compared to the control MDDCs cultivated with LPS alone. PTX-treated MDDCs which were induced to mature with LPS produced lower levels of TNF-alpha, IL-12 and IL-18 and higher levels of IL-10 than corresponding control NIDDCs. PTX did not significantly alter endocytosis of dextran by both immature and mature MDDCs. Cumulatively, our results show for the first time that PTX might impair differentiation, maturation and function of human MDDCs in vitro, suggesting an additional mechanism of its immunomodulatory activity.

The aim of this research was to evaluate maxillofacial weapon-related injuries from the epidemiological, clinical, and forensic points of view. Analysis of medical records of 183 patients treated for weapon-related injuries in Belgrade maxillofacial surgery clinics in the period 1988 through 2002 has been carried out. Most treated patients were male, 21 to 50 years of age, and injured during the war in the territory of the former Yugoslavia. Injuries involving the mandible were the most frequent (40%); firearm (85%) and perforating (70%) wounds occurred more frequently than explosive (25%) and penetrating (30%) wounds; in certain cases, medical records were incomplete and thus useless for forensic court expertise and evidence. A rapid increase in maxillofacial weapon-related injuries was recorded in the period from 1991 to 1995 as a result of war injuries; high-velocity projectiles caused most of the injuries. It is necessary to keep adequate medical records for successful forensic and court expertise and evidence.

A murine monoclonal antibody (mAb), 3F10, was produced by fusion of spleen cells obtained from mice immunized with a rat cortical thymic epithelial cell line (R-TNC.1) stimulated with interferon-gamma and P3X myeloma cells. 3F10 recognized an antigen expressed both on thymocytes and non-lymphoid cells in the thymus. Flow cytometry showed that 3F10 stained more than 98% thymocytes and 90% R-TNC.1 cells. Immunoprecipitation and Western blot studies demonstrated that 3F10 reacted with molecules of 55000 and 65000 MW from both thymocyte and R-TNC.1 cell lysates. 3F10 recognized the same antigen on Chinese hamster ovary cells transfected with rat Crry as did 5I2 mAb, confirming the specificity of 3F10 mAb for the rat homologue of mouse Crry/p65, a membrane-bound complement regulatory protein. 3F10 mAb induced homotypic aggregation of thymocytes and exhibited an additive effect on the aggregation evoked by phorbol myristate acetate. The aggregation was dependent on active cell metabolism, intact cytoskeleton, divalent cations and activation of protein phosphatases 1 and 2A (as assessed by use of okadaic acid). In contrast, H-7, HA1004 and genistein partially inhibited, whereas staurosporine potentiated the aggregation of thymocytes triggered by 3F10. 3F10 mAb also stimulated binding of thymocytes to the R-TNC.1 line. Both homotypic and heterotypic adhesive interactions are mediated by leucocyte function-associated antigen-1 (LFA-1). In addition, 3F10 stimulated proliferation of thymocytes induced by suboptimal concentrations of concanavalin A. These data suggest that rat Crry/p65 might be involved in the regulation of both cell adhesion and activation of thymocytes. This is a novel, non-complement-dependent function of Crry/p65.