[Changes in the amount of ATP in HeLa cells under the action of He-Ne laser radiation]. / Izmenenie kolichestva ATF v kletkakh HeLa pod vozdeistviem izlucheniia He-Ne lazera.

Amount of ATP in HeLa cells in various phases of growth was measured after He-Ne laser irradiation (100 J/m2, 10 W/m2, 10 s) by a bioluminescent luciferin-luciferase method. In cells of the exponential phase of growth, the amount of ATP (basal level 8 x 10(-16) mole/cell) starts to increase in 15 min after the irradiation with a maximum (170% above the basal level) at 20 min, and then decreases gradually to the basal level. The sensitivity of the cells to He-Ne laser radiation is lowest in lag-phase of growth, then increases to a plateau (approximately 185% above the control level) from 5th day of cultivation.

[The effect of He-Ne laser radiation on the adhesive properties of the cell membrane]. / Vliianie izlucheniia He-Ne lazera na adgezivnye svoistva kletochnoi membrany.

Changes in the number of individual cells and cellular complexes after a standard dispergation procedure were used as a criterion for evaluating the strength of the cellular contacts at various time-points after the irradiation of HeLa monolayers with a He-Ne laser (100 J/m2, 10 W/m2, 10 s). The per cent of cellular complexes increased after the irradiation, being maximal (19.5 +/- 0.6) at 30 minutes of post-irradiation, and then decreased to the control level (12.1 +/- 0.5). Per cent of cellular complexes increased again at longer intervals (90-180 min) after the irradiation.

[The effect of He-Ne laser radiation on the survival of HeLa cells subjected to ionizing radiation]. / Vliianie izlucheniia He-Le lazera na vyzhivaemost' kletok HeLa, podvergnutykh deistviiu ioniziruiushchei radiatsii.

A monolayer of HeLa cells, at the stationary phase of growth, exposed to He-Ne laser radiation (632.8 nm; 100 J/m2) either 5 min or 60 min prior to gamma irradiation (0.1-10 Gy; 6.75 Gy/min), or 5 min after irradiation has been investigated. With a 5-min interval between irradiation sessions (both sequences) the survival curves are virtually the same as those for gamma-irradiated cells only. With He-Ne laser radiation delivered 60 min before gamma irradiation with doses exceeding 5 Gy, a fraction of radioresistant cells is identified whose D0 is almost twice as high as D0 of basic cell mass (3.6 and 1.7 Gy respectively. The survival curve becomes a two-component one. A hypothesis is proposed that He-Ne laser radiation activates, in some cells, the processes that promote the repair of radiation damages.

[Photosensitized inactivation of HeLa tumor cells by phthalocyanines]. / Fotosensibilizirovannaia inaktivatsiia opukholevykh kletok HeLa ftalotsianinami.

The combined effect of tetrasulfonated phthalocyanine (TSPC, 1.0 microM) or chloroaluminum phthalocyanine (CAPC, 1.0 microM) and copper vapour laser radiation (lambda = 670 nm) causes a dose dependent decrease in the survival rate of HeLa cells at exponential and stationary growth phases estimated by the trypan blue exclusion test or colony-forming ability test. TSPC is two times and CAPC seven times more effective, with regard to lethality, than the known photosensitizer, a hematoporphyrin derivative.

[Specificity of the lethal and mutagenic actions of pico-second laser pulses of 532-nm wavelength]. / Issledovanie spetsifiki letal'nogo i mutagennogo deistviia pikosekundnykh lazernykh impul'sov s dlinoi volny 532 nm.

A study was made of the lethal effect of pulse laser (second harmonic Nd+3:YAG laser of 532 nm, pulse length 3.3.10(-11) s, peak intensity from 4.10(12) to 1.10(14) W/m2) on HeLa cells at the phases of active and stationary growth, and lethal and mutagenic effects of this radiation on E. coli cells. As was shown, HeLa cells at both growth phases and E. coli cells exhibited low sensitivity to laser radiation at lambda = 532 nm.

[Radiation-modifying effect of UV and visible laser light]. / Radiomodifitsiruiushchee deistvie UF- i vidimogo lazernogo sveta.

A radiomodifying effect of the three types of laser radiation has been studied on HeLa cell culture. Low-intensity UV-radiation delivered as high repetition rate nanosecond pulses (the second harmonic of the copper vapours laser lambda = 271 nm) somewhat reinforces, and continuous low-intensity red radiation (He-Ne laser, lambda = 632.8 nm) of certain doses weakens the effect of 5 Gy gamma-radiation.

[Growth kinetics of HeLa tumor cells during subculturing after irradiation with low-intensity red light in the stationary growth phase]. / Kinetika rosta opukholevykh kletok HeLa pri subkul'tivirovanii posle oblucheniia nizkointensivnym krasnym svetom v statsionarnoi faze rosta.

The curves of relative growth rate of HeLa cells were studied after their irradiation at the stationary growth phase (He-Ne laser, lambda = 632.8 nm, D = 100 J/m2) and reinoculation to the fresh medium in different periods after the irradiation. The irradiation evokes changes in cells of the stationary phase which are realized in subcultivation. When the interval between irradiation and inoculation is short (5 min), the cell growth is inhibited; when the interval becomes longer (up to 4 h), the cell growth in the exponential phase increases. In the HeLa cell culture with the stimulated growth only a part of cells are able, to reach the stationary growth phase.