Activation of human blood monocytes by oxidized polyunsaturated fatty acids: a possible mechanism for the generation of lipid peroxides in the circulation.

The ability of native and oxidized lipids and lipoproteins to stimulate production of reactive oxygen species (ROS; superoxide and hydrogen peroxide) by human blood monocytes has been studied in vitro. Neither native human low density lipoprotein (LDL), ''altered'' LDL (oxidized either by lipoxygenase, activated human monocytes or air) nor oxidized cholesterol had any significant effect on ROS production of monocytes. However, different oxidation products of a lipid emulsion (Lipofundin; largely consisting of linoleic acid oxidized either by lipoxygenase, Fe3+ or ultraviolet irradiation) greatly enhanced ROS production of monocytes. A hypothesis that activation of circulating leucocytes by oxidized fatty acids may generate oxidized plasma LDL, was tested in rabbits. Characteristics of LDL, separated from rabbit plasma 6 h after intravenous injection of an oxidized lipid emulsion, was compared to that of LDL isolated before the lipid treatment. Post-treatment LDL-fraction of plasma had increased lipid peroxide content and compared to the pretreatment LDL, caused a threefold increase in the incorporation of cholesterol into cultured (rat aortic) endothelial cells. The observed intense and lasting stimulation of monocytes by oxidized polyunsaturated fatty acids in vitro, and the generation of ''altered'' LDL by these oxidized lipids in vivo suggests a mechanism by which atherogenic oxidized LDL could form in the circulation.     

Current treatment of thoracic empyema in adults

Experiences obtained with 400 cases of thoracal empyema are described. The fact that the rate of lethality was 18.7% until present points out to the severity of the disease. The semi-conservative therapeutical methods used by the author (drainage, drainage and pleura lavage, pleura lavage and thoracoscopy, balance drainage) are presented. With their sensibly more frequent use the rate of operation could be reduced by 8% (from 36.5% to 28.5%) and the lethality rate by 7.6% (from 18.7% to 11.1). Further improvement of the results may be expected of the increased number of early detection (basic care), concentration of empyemic patients in special institutes (departments, wards) and due to it of a more efficient special treatment of uniform contemplation.     

Gas chromatographic assay of methyltestosterone in tablets.

A simple gas chromatographic procedure has been developed for the determination of methyltestosterone in bulk powders and in tablets. Two new silyl ether derivatives of methyltestosterone have been prepared using dimethylethylsilylimidazole (DMESI) and dimethylisopropylsilylimidazole (DMiPSI). The method is accurate and selective for methyltestosterone within the concentration range 0.1-1.5 micrograms microliters-1.     

A selective LC/RIA for dexamethasone and its prodrug dexamethasone-21-isonicotinate in biological fluids.

A combined LC/RIA procedure is described for the selective determination of dexamethasone (DEX) and its prodrug dexamethasone-21-isonicotinate (DIN) in plasma. The low affinity of the employed dexamethasone antiserum for DIN (cross-reactivity less than 0.5%) allowed the direct determination of DEX in plasma extracts. For the determination of DIN, both substances of interest were separated by LC, the DIN containing fraction was collected, hydrolysed and the generated DEX was consequently assayed by radioimmunoassay. The assay detection limits were 0.1 ng ml-1 for DEX and 0.75 ng ml-1 for DIN. For both substances, inter- and intra-day variabilities (RSDs) were 6 and 12%, respectively.     

Cultures of Langerhans cells and co-culture with lymphoid cells: Relevance to toxicology and pharmacology

Langerhans cells are an essential component of cutaneous immunological defence mechanisms. They are mononuclear dendritic cells derived from bone marrow, which are present in the squamous epithelia, particularly skin. Langerhans cells show marked changes in phenotype and function when epidermal cell suspensions are prepared according to a trypsinization protocol and placed in culture for 1–3 days. They seem to mature and acquire most of the features of lymphoid dendritic cells, especially the interdigitating dendritic cells present in lymph nodes. This observation supports the assertion that resident Langerhans cells take up foreign antigens and then migrate through dermal lymphatics to local lymph nodes where they function as antigen-presenting cells. Thus, Langerhans cells play a pivotal role in the primary immune response and in the pathogenesis of skin diseases. In the past, most therapeutic treatment of skin diseases was achieved by administration of pharmacological agents by epicutaneous application. More recently, the determination of the toxicity of drugs and their pharmacological mechanisms has required the development of in vitro models to explore their potential effects at the cellular level. The effects of different agents (physical and chemical) on the density and function of fresh or cultured Langerhans cells are reviewed.     

Frühes Ovarialkarzinom

Patients with early ovarian carcinoma have a much better survival outcome than patients with more advanced disease. Comprehensive surgical staging is crucial for the determination of prognosis and treatment planning. During 2003, the first randomized trials were published demonstrating that adjuvant platinum based chemotherapy improves recurrence free and overall survival. Current treatment recommendations are largely based on the results of these studies. Accordingly, systemic adjuvant therapy should be offered to patients with disease stage Ib or higher and to patients with moderately differentiated or undifferentiated tumors. Due to incomplete surgical staging, the stage of disease in the patients included in these studies is probably underestimated, and only a fraction of the actual advanced stage patients is included.