Atomic force microscopy (AFM), a unique tool to investigate drug treatment of cancer cells, was used to analyze the anti-neoplastic activity of adriamycin by comparing DNA structures of non-treated and adriamycin-treated Ehrlich tumor cells. The non-treated cells exhibited a highly branched intact chromatin structure, related to the intensive DNA replication in cancer cells. Images from adriamycin-treated tumor cells showed that the DNAchains were broken and the chromatin structure had been destroyed. Possible explana- tions for these effects of adriamycin are considered: breakage of hydrogen bonding, oxida- tion and intercalation effects, as well as the poisoning of topoisomerase enzyme. DNA fractal and multifractal analyses, performed in order to evaluate the degree of bond scission, showed that the treated DNA had become more fractal compared to non-treated DNA.

PURPOSE To study in vitro the antioxidative effect of 6 Satureja montana L. extracts on free radicals and their antiproliferative effect on human tumor cell lines. MATERIALS AND METHODS The antioxidative effect of extracts on 2, 2-diphenyl-1-picryhydrazyl (DPPH) radical was investigated by electron spin resonance (ESR) spectroscopy. Cell growth effect was measured by sulforhodamine B colorimetric assay on HeLa (human cervix epidermoid carcinoma), HT-29 (human colon adenocarcinoma), and MCF-7 (human breast adenocarcinoma) cell lines. IC(50) values were calculated from the concentration response curves following 48 h exposure time. RESULTS The antioxidative activity of extracts increased dose-dependently at mass concentrations ranging from 0.05 to 0.3 mg/ml, and decreased in the following order: n-butanol > methanol > water > ethyl acetate > petroleum ether. All extracts effected cell growth but in a different way, depending on the extract dose and cell line. Extracts exhibited antiproliferative effect on HeLa cell line with IC(50) values ranging from 0.41 to 0.84 mg/ml except petroleum ether (IC(50) >1 mg/ml). Petroleum ether and chloroform extracts stimulated proliferation of HeLa cells within a concentration range from 0.0625 to 0.125 mg/ml. No extract reduced MCF-7 cells growth by 50% even at the concentration of 1 mg/ml. Only petroleum ether and chloroform extracts induced significant growth inhibition of HT-29 cells (IC(50) was approximately 0.74 mg/ml for both extracts). Strong stimulation of HT-29 proliferation was observed within a concentration range from 0.0625 to 0.25 mg/ml for petroleum ether, n-butanol and chloroform extract, and from 0.0625 to 0.5 mg/ml for methanol and water extracts, respectively. CONCLUSION The obtained results indicated that Satureja montana L. extracts are strong antioxidants in vitro. ESR data demonstrated that n-butanol, methanol and water Satureja montana L. extracts possess high antioxidative activity. Chloroform extract did not show any antioxidative activity. Satureja montana L. extracts selectively inhibited the growth of human tumor cells.

Dark red monocrystals of title complex were prepared by the reaction of water solutions of Na3[Co(NO2)6] and L×2H2O in mole ratio 1:1. The Co(III) is sited in an octahedral environment. The equatorial plane is formed by a tridentate coordination of the ligand (L) and one NO2 molecule, while the other two NO2 molecules are in axial positions. The ligand is coordinated to the Co(III) atom through O3, N1 and O4 atoms, forming two fused chelate rings, one being five-membered and one a six-membered one. All atoms in the chelate and phenyl rings are approximately coplanar. The angle between the mean plan of the equatorial NO2 and the mean plane defined by the two chelate rings is 28.1(3)°. The Co-N bond lengths for the two axial NO2 are about 0.03 Å longer than that with the equatorial NO2. The two axial NO2 are coplanar. The complex molecule possesses eight oxygen atoms capable of acting as proton acceptors in the hydrogen bonds, but there are only two groups (one N-H and one O-H) able to participate as proton donors. As a consequence, six oxygen atoms from NO2 ligands form weak C-H...O hydrogen bonds with only one exception for O4 atom which participates in two strong O-H...O hydrogen bonds. Because of that the N-O4 bond is significantly longer than the rest of N-O bonds in the NO2 ligands. Data were collected on an Enraf-Nonius CAD-4 diffractometer using Mo K radiation ( = 0.71069 Å) and /2 scans in 1.41 to 25.47° range and were corrected for Lorentz and polarization effects. The structure was solved by direct methods and difference-Fourier methods, and refined by full matrix least-squares using SHELXL97 program to a final R = 0.0431 for 2938 reflections with I > 2 I. Crystallographic data: CoC13H22N7O10, Mr = 495.3, monoclinic, space group P 21/c, a = 14.936(3) Å, b = 7.773(3) Å, c = 17.463(3)Å, = 104.26(3) °, V = 1964.9(9) Å, Z = 4, Dc = 1.674 Mg/m , (MoK ) = 0.944 mm, Mo K radiation, = 0.71073 A, GooF = 1.055.