background: perforin is known to be important in cytolytic activity mediated by natural killer (nk) cells.   objective: to study the relationship between the efficiency of nk and lymphokine-activated killer (lak) cells activity, and the expression of perforin and hla class i molecules.   methods: lak cells were generated by in vitro culturing of human peripheral blood lymphocytes (pbls) in the ...

The present study was motivated by the paucity of reports on cellular internalization of ingested titanium dioxide (TiO(2)) nanoparticles (nano-TiO(2)). The model invertebrate (Porcellio scaber, Isopoda, Crustacea) was exposed to food dosed with nano-TiO(2) containing 100, 1,000, 3,000, or 5,000 µg nano-TiO(2) per gram of food. After 14 d of exposure, the amount of Ti in the entire body was ana...