PIXE cluster analysis of ancient ceramics from North Syria

C1 - Journal Articles Referee

Reattachment and apoptosis after plasma needle treatment of cultured cells

Nonthermal plasmas can be used to locally influence cell adhesion: cells can be removed from their surroundings without causing necrosis. In fact, cells remain alive and can reattach within hours. This phenomenon may, in the future, be used for microsurgical procedures. Another method to remove cells is to induce apoptosis or programmed cell death. This type of cell death is preferred above necrosis, which may cause inflammation reactions. When the detached cells are allowed to reattach and grow, it is important to know their condition. Therefore, long-term effects of plasma-needle treatment were assessed, with special focus on reattachment and apoptosis. The cells were treated using a plasma needle. This device generates a small (1-mm diam.) plasma at atm. pressure. To avoid any heat effects, it is important that the plasma temp. is at or below physiol. temp. This is the case for the plasma needle

Plasma treatment of mammalian vascular cells: a quantitative description

For the first time, quantitative data was obtained on plasma treatment of living mammalian cells. The nonthermal atmospheric discharge produced by the plasma needle was used for treatment of mammalian endothelial and smooth muscle cells. The influence of several experimental parameters on cell detachment and necrosis was tested using cell viability assays. Interruption of cell adhesion (detachment) was the most important cell reaction to plasma treatment. Treatment times of 10 s were enough to detach cells in the cultured cell sheet. Under extreme conditions, cell necrosis occurred. Cell detachment without necrosis could be achieved at low voltages. It was shown that the thickness of the liquid layer covering the cells was the most important factor, which had more influence than treatment time or applied voltage. The results show no remarkable differences between the responses of the two cell types

Electric discharge plasmas influence attachment of cultured CHO k1 cells

Non-thermal plasmas can be generated by electric discharges in gases. These plasmas are reactive media, capable of superficial treatment of various materials. A novel non-thermal atmospheric plasma source (plasma needle) has been developed and tested. Plasma appears at the end of a metal pin as a submillimetre glow. We investigate the possibility of applying the plasma needle directly to living tissues; the final goal is controlled cell treatment in microsurgery. To resolve plasma effects on cells, we study cultured Chinese hamster ovarian cells (CHO-K1) as a model system. When these are exposed to the plasma, instantaneous detachment of cells from the surface and loss of cell-cell interaction is observed. This occurs in the power range 0.1-0.2 W. Cell viability is assessed using propidium iodide (PI) and cell tracker green (CTG) fluorescent staining utilizing confocal laser scanning microscopy (CLSM). Detached cells remain alive. Use of higher doses (plasma power >0.2 W) results in cell necrosis. In all cases, plasma-influenced cells are strictly localized in submillimetre areas, while no reaction in surrounding cells is observed. Due to its extreme precision, plasma treatment may be applicable in refined tissue modification. Bioelectromagnetics 25:362-368, 2004. © 2004 Wiley-Liss, Inc