Current development of the human and environmental contamination in the Bryansk-Gomel Spot after the Chernobyl accident.

Up to 1991, it was assumed that after the Chernobyl accident in 1986 the time development of radioactive contamination with regard to environment, foodstuff, and man would decrease due to migration processes in the soil, radioactive decay, and protective measures. This assumption was confirmed by all measurements in the first few years after the accident. Since 1991, however, a change in this development has been observed, as many measurements show stagnation or in some cases even an increase of foodstuff and human contamination.

Fibronectin increases both non-adherent cells and CFU-GM while collagen increases adherent cells in human normal long-term bone marrow cultures.

Normal haematopoietic proliferation and differentiation occur within the human bone marrow microenvironment which is comprised of stromal cells including fibroblasts, adipocytes, macrophages and endothelial cells as well as the extracellular matrix made of collagen, fibronectin, laminin, vitronectin, thrombospondin and haemonectin. All haematopoietic progenitor cells including primitive LTC-IC, multilineage CFU-mix, myeloid CFU-GM and erythroid BFU-E adhere to the heparin-binding domains of the extracellular matrix component fibronectin. Human long-term bone marrow cultures (LTHBMC) represent the best available approximation for the in vivo marrow microenvironment in which the proliferation and differentiation of haematopoietic progenitor cells depend on the presence of marrow stromal cells and their attendant matrices.

Mitogenic activity of high molecular polysaccharide fractions isolated from the cuppressaceae Thuja occidentalis L. enhanced cytokine-production by thyapolysaccharide, g-fraction (TPSg).

Thuja polysaccharide g fraction (TPSg) was shown to be an inducer of the CD4+ fraction of the human peripheral blood T-cell subset (1,2). Furthermore, it could be demonstrated that TPSg is a potent inhibitor of the expression of HIV-1-specific antigens and of the HIV-1-specific reverse transcriptase (3). This report deals with the cytokine pattern induced by TPSg in human peripheral blood lymphocyte (PBL) and purified monocyte/macrophage cultures.

Mechanisms contributing to the virus persistence in Aleutian disease.

In this review published results and further studies concerning the persistence of Aleutian disease virus (ADV) isolate SL3 are presented. By Southern blot and in situ hybridization with strand-specific RNA probes focal replication of ADV-DNA was demonstrated in spleen, mesenteric lymph nodes, sporadically in mononuclear cells of the peripheral blood and bone marrow cells. These findings further support the concept of the lymphotropism of ADV.