Author/Editor     Miklavčič, D; Pucihar, G; Mir, LM; Puc, M; Flisar, K; Maček-Lebar, A; Mali, M; Serša, G; Kranjc, S; Čemažar, M; Petkovšek, M; Nastran, J
Title     Increased pulse repetition frequency for effective and less painful electrochemotherapy
Type     članek
Source     Adv Comput Bioeng Ser
Vol. and No.     Letnik 7
Publication year     2003
Volume     str. 391-400
Language     eng
Abstract     Electrochemotherapy is a technique where electric pulses in combination with chemotherapeutic agents are applied to tumor cells. In general, patients fmd electrochemotherapy tolerable, in spite of unpleasant sensations associated with contraction of muscles located in the vicinity of the electrodes. Usually a train of eight electric pulses with repetition frequency of 1 Hz is applied to the tumors and each pulse in the train provokes muscle contraction. The use of pulses with repetition frequency higher than the frequency of tetanic contraction would represent reduced number of muscle contractions and unpleasant sensations. To study the possibilities for the use of higher pulse repetition frequencies in ECT, the effect of increased pulse repetition frequency on the uptake of Lucifer Yellow in vitro, the effect of increased pulse repetition frequency on the tumor growth after ECT in vivo and the effect of different pulse repetition frequencies on the muscle response in healthy volunteers were investigated. In vitro results showed that the uptake of Lucifer Yellow stays at similar levels at frequencies up to 1 kHz. In vivo experiments demonstrated that ECT with higher pulse repetition frequencies is still effective. Muscle response measured at different pulse repetition frequencies confirmed that the use of pulse repetition frequencies above the frequency of tetanic contraction reduces the number of individual muscle contractions and further increase of the pulse repetition frequency results in decreased muscle response due to shorter total duration of pulse train.
Descriptors     TUMOR CELLS, CULTURED
ELECTROPORATION
DRUG DELIVERY SYSTEMS
SARCOMA, EXPERIMENTAL
BLEOMYCIN
MICE
MUSCLE CONTRACTION