Can lucifer yellow indicate correct permeability of biological cell membrane under an electric and magnetic field?

The effect of external magnetic and electric fields, in the range of electroporation and magnetoporation, on Lucifer Yellow [LY] fluorescence in the absence of cells is studied. Electric-field-induced quenching and magnetic field-induced increase are observed for fluorescence intensity of LY. Regard to the fact that the variation of field-induced fluorescence, even in the absence of cells, can be observed, the application of LY, as a marker, is debatable in electroporation and magnetoporation techniques

[Comparison of low voltage amplitude electrochemotherapy with 1 Hz and 5 kHz frequency in volume reduction of mouse mammary tumor in Balb/c Mice]

Electrochemotherapy [ECT] is an efficient technique that high intensity electric pulses in combination with chemotherapeutic drugs are applied to tumor cells. The most important unpleasant sensation of electrochemotherapy is muscle contraction. To resolve this problem, there are two solutions: first, increasing the repetition frequency of electric pulses above the tetanic frequency; and, second, reducing the voltage amplitude. ECT using 1 Hz or 5 kHz frequency at high amplitude examined and no difference response of the tumor treatment was observed. But the role of frequency in low amplitude ECT not examined. Therefore, the present study compared the anti-tumor effectiveness of electrochemotherapyusing electric pulses with frequencies of 1 Hz and 5 kHz at 70 v/cm amplitude. ECT of spontaneous mouse mammary tumor [SMMT] transplanted in Balb/c was performed with intratumoral injection of bleomycine and applied four different electric pulse protocols: 1- a train of 8 pulses with duration 50 ms, 1 Hz frequency and 70 v/cm amplitude, 2- a train of 4000 pulses with duration 100 micros, 5k Hz frequency and 70 v/cm amplitude,3- a train of 8 pulses with duration 100 micro s, 1 Hz frequency and 1000 v/cm amplitude,4- a train of 8 pulses with duration 100 micros, 5 kHz frequency and 1000 v/cm amplitude. Our data demonstrate significant differences in tumor volumes between mice treated by 70 V/cm and 5 kHz frequency compared to1 Hz frequency but inhibited tumor growth in high amplitude with 1 Hz and 5 kHz is comparable. Based on these results, the pulses with 70 v/cm and 5 kHz frequency are most effective. On the basis of these results the frequency effect of electric pulses is important in low amplitude ECT.

Antitumor efficiency of electrochemotherapy by high and low frequencies and repetitive therapy in the treatment of invasive ductal carcinoma in Balb/c Mice

In electrochemotherapy [ECT], there is an unpleasant sensation of muscle contraction when using a low frequency [1 Hz]. Therefore, by increasing the pulse frequency above the tetanic frequency this painful sensation can be reduced. The aim of the present study is to compare the treatment efficiencies of low and high frequency ECT, and estimate the effect of its repeated sessions. We transplanted invasive ductal carcinoma into the flanks of female Balb/c mice. ECT was performed on the mice by the use of 8 pulses, 1000 v/cm, of 100 micro s duration at 1 Hz and 5 kHz repetition frequencies along with intra-tumoral injections of bleomycin. We also used this ECT protocol for the second therapy session six days after tumour regrowth. The effect of treatment was measured by calculating the tumor volumes for 24 days following treatment. Statistical analysis was performed with ANOVA. ECT at 1 Hz and 5 kHz pulse frequencies demonstrated significant inhibition of tumor growth, but after the first treatment the tumours began to regrow. Repetitive ECT sessions increased the curability of tumors up to 40% in the group treated by 1 Hz frequency and 60% in the group treated with 5 kHz frequency. Our results demonstrate that the effects of 1 Hz and 5 kHz pulse repetition frequencies are comparable for inhibited tumour growth. Repetitive treatment can improve the effectiveness of ECT