BACKGROUND Epidemiological evidence has suggested that some childhood acute lymphoblastic leukemia (ALL) may be initiated in utero and may have an infectious etiology. The human polyomavirus JC virus (JCV) has been discussed as a candidate virus, but its presence has not been demonstrated in leukemia cells from children with ALL. The aim of this study was, therefore, to investigate if prenatal human polyomavirus infection could still indirectly be correlated to the development of childhood ALL. PROCEDURE Fifty-four Guthrie cards (stored, dried blood spots filter papers, routinely collected from newborns for different screening analyses), collected at 3-5 days of age, from Swedish children who subsequently developed ALL, as well as from 37 healthy controls, were investigated by nested PCR for the presence of human polyomaviruses JCV and BK virus (BKV). RESULTS JCV and BKV DNA were not detected in any of the Guthrie cards from ALL patients or from healthy controls, although all tested samples had amplifiable DNA as confirmed by an HLA DQ PCR. CONCLUSIONS JCV or BKV were not found in any of the dried blood spots of children who later developed ALL or in the healthy controls. These findings suggest that it is unlikely that childhood ALL is associated with an in utero infection with JCV or BKV, although it is not possible to exclude an association with an in utero infection that has become latent in the kidneys with very low levels of circulating virus at birth.

The platinum (II)complexes, cis-[PtCl2(CH3SCH2CH2SCH3)] (Pt1), cis-[PtCl2(dmso)2] (dmso is dimethylsulfoxide; Pt2) and cis-[PtCl2(NH3)2] (cisplatin), and taxol (T) have been tested at different equimolar concentrations. Cells were exposed to complexes for 2 h and left to recover in fresh medium for 24, 48 or 72 h. Growth inhibition was measured by tetrazolium WST1 assay Analyses of the cell cycle, and apoptosis were performed by flow cytometry, at the same exposure times. The IC50 value of each platinum(II) complex as well as combination index (CI; platinum(II) complex + taxol) for various cytotoxicity levels were determined by median effects analysis. MCF7 cells were found to be sensitive to both Pt1 and Pt2 complexe These cisplatin analogues influenced the cell growth more effectively as compared to cisplatin. Cytotoxic effect was concentration and time-dependent. Profound growth inhibitory effect was observed for Pt1 complex, across all its concentrations at all recovery periods. A plateau effect was achieved three days after treatment at Pt1 concentrations ≤ 1 μM. Pt2, however, decreased MCF7 cells survival only for the first 24 h ranging between 50-55%. Pt2 cytotoxicity sharply decreased thereafter, approaching 2 h - treatment cytotoxicity level. The median IC50 values for Pt1 and Pt2 were similar (0.337 and 0.3051 μM, respectively) but only for the first 24 h. The IC50 values for Pt1 strongly depend on the recovery period. On simultaneos exposure of cells to taxol and platinum(II) complexes no consistent effect was found. The Cls for combinations of taxol with Pt1 or Pt2 revealed cytotoxic effects that were in most Cases synergistic (Pt1) or less than addtiive (Pt2). Flow cytometry analysis has shown that each platinum(II) complex induced apoptosis in MCF7 cells. The level of apoptosis correlated with cytotoxicity level for the range concentrations. Both cisplatin analogues, at IC50 concentrations, increased the number of MCF7 cells in G0G1 phase of cell cycle. Pt2-treated cells remained arrested in G0G1 phase up to 72 h after treatment. Combination of Pt2 and taxol caused further arrest of cells in G0G1 phase (24 h) in parallel with strong decrement of G2M phase cells.

This paper presents the basic chemical characteristics of buckminsterfullerene-molecule CM60 and some of its biologically active derivatives. This new form of carbon with unique properties, discovered in 1985, is a very reactive species undergoing a variety of chemical reactions leading to a wide spectrum of possible covalent derivatives. Besides covalent compounds, fullerene reacts with different dopants to form non-covalent complexes, including endohedral, exohedral systems (intercalates). The review of the most significant papers on noncovalent and covalent derivatives and their biological activity is given, as well as our results in this field. Formation of intercalates of fullerene with small molecules of aliphatic alcohols is described and the importance of topology and size of dopants and the role of solvents in formation of intercalates is explained. Original synthesis of bromine derivative C60Br24 and water-soluble polyhydroxy derivative C60(OH)24 is described. Antioxidative effects of the latter compound were investigated in chemical model system and in vitro system of human neoplasmatic cells. The paper also gives theoretical explanation of addition C60R24 derivatives together with assumption about antioxidative activity of fullerol. .