Current trends and perspectives in nutrition and cancer prevention.

There is an increasing evidence that dietary phytochemicals may play important roles as chemopreventive or chemotherapeutic agents in prevention of many diseases, including tumors. The purpose of this study was to examine antimutagenic effects and effect on the immune response of representative series of substances which commonly occur in human diet. Using the Ames bacterial mutagenicity test and in vivo chemiluminescence test, we investigated antigenotoxic and immunomodulatory effects of juices and vegetable homogenates (carrot + cauliflower, cauliflower, red cabbage, broccoli, onion, garlic) on the genotoxicity of AFB1 and pyrolysates of aminoacids. Using the Ames test and in vivo micronucleus, the chemiluminescence test, the blastic transformation test and the comet assay we examined antimutagenic effects of chemically identified chemoprotective substances in the pure form (resveratrol, diallylsulphide, phenethyl isothiocyanate, ellagic acid, epigallocatechin gallate, genistein and curcumin) on mutagenicity induced by three reference mutagens: aflatoxin B1 (AFB1), 2-amino-3-metylimidazo[4,5,-f] chinolin (IQ) and N-nitroso- N-metylurea (MNU) and effect of phytochemicals on the immunosuppression caused by these mutagens. All complete vegetable homogenates and substances of plant origin tested, showed a clear antimutagenic and immunomodulatory activities on mutagenicity and immunosuppression induced by reference mutagens. Only in the Ames test the effect of some phytochemicals against direct mutagen MNU was lower compared to indirect mutagens AFB1 and IQ. Similarly, resveratrol and epigallocatechin gallate had no inhibitory effect on mutagenicity MNU in the Ames test.

[Phagocyte function deficiency determined by methods using chemotaxis and chemiluminescence]. / Deficit fagocytárních funkcí zjistovany metodou chemotaxe a chemiluminiscence.

The chemotactically oriented and not oriented migration of polymorphonuclear leucocytes was examined in 21 patients with acute ulcerative gingivitis, using the method of assessment of chemotaxis under an agarose layer. In the same group of patients also the chemiluminescence of leucocytes was assessed. In 16 patients the chemotactically oriented and non-oriented cell migration was reduced. In four patients both types of activity were enhanced. The chemiluminescent leucocyte activity was reduced in all patients of this group.

The immunological properties of listerial complex Ei.

Factor Ei, besides exerting toxic reactions, is amphipathic, antigenic, chemotaxinogenic, causes blastic transformation, adjuvant effect, hypersensitivity (MIF, skin test), activates the RES (splenomegaly), increases the macrophage production, prevents listerial infection in mice, mycobacterial infection in guinea pigs and enhances the effect of BCG experimental tuberculosis and neoplasia in mice (Sa 180).

Changes in the migratory activity of polymorphonuclear leukocytes after administration of Freund's adjuvant.

Spontaneous and chemotactic activity of polymorphonuclear leukocytes, obtained from the peritoneal cavity, was studied after administration of complete and incomplete Freund's adjuvant to rabbits at intervals of 18-26 d after adjuvant injection. Whereas injection of both complete and incomplete adjuvant increased spontaneous migration of rabbit polymorphonuclear leukocytes, the migration directed by the chemotactic signal, induced in fresh serum by E. coli endotoxin, was decreased. The chemotaxigenic activity of two factors, isolated from cell walls of Listeria monocytogenes was also tested: factor Ei (its most potent component is lipopolysaccharide) and a purified phenol extract of lipopeptidopolysaccharide nature.