Sorin Comorosan

Isolation and characterization of a rapidly labelled RNA from mouse liver mitochondria

Abstract 1. 1. The isolation and characterization of a rapidly labelled RNA from mouse liver mitochondria is described. This RNA fraction was shown to have the characteristics of messenger RNA (mRNA). 2. 2. The rapidly labelled RNA fraction exhibits a molecular weight of 1.5 · 10 5 and is continuously synthesized both in vivo and in vitro for 120 min. 3. 3. The amino acid incorporation into mitochondria in vitro is slightly stimulated by this RNA fraction. It also prevents the inhibitory effects of chloramphenicol. 4. 4. Hybridization of the rapidly labelled RNA with mitochondria DNA suggests the mitochondrial origin of this RNA.

Green light radiation effects on free radicals inhibition in cellular and chemical systems

Free radicals generation is inhibited through green light (GL) irradiation in cellular systems and in chemical reactions. Standard melanocyte cultures were UV-irradiated and the induced cellular reactive oxygen species (ROS) were quantified by the fluorescence technique. The same cell cultures, previously protected by a 24h GL exposure, displayed a significantly lower ROS production. A simple chemical reaction is subsequently chosen, in which the production of free radicals is well defined. Paraffin wax and mineral oil were GL irradiated during thermal degradation and the oxidation products checked by chemiluminescence [CL] and Fourier transform infrared spectra [FT-IR]. The same clear inhibition of the radical oxidation of alkanes is recorded. A quantum chemistry modeling of these results is performed and a mechanism involving a new type of Rydberg macromolecular systems with implications for biology and medicine is suggested.

Optical manipulation of Saccharomyces cerevisiae cells reveals that green light protection against UV irradiation is favored by low Ca2+ and requires intact UPR pathway

Optical manipulation of Saccharomyces cerevisiae cells with high density green photons conferred protection against the deleterious effects of UV radiation. Combining chemical screening with UV irradiation of yeast cells, it was noted that the high density green photons relied on the presence of intact unfolded protein response (UPR) pathway to exert their protective effect and that the low Ca2+ conditions boosted the effect. UPR chemical inducers tunicamycin, dithiotreitol and calcium chelators augmented the green light effect in a synergic action against UV‐induced damage. Photo‐manipulation of cells was a critical factor since the maximum protection was achieved only when cells were pre‐exposed to green light.

Effects Induced in Complex Biological Systems by High Density Green Photons

It is known that light interaction with matter may generate an optical force, which may produce modifications at the physical and chemical level. The basic technique of the field uses strongly focused laser beams that trap small objects and manipulate local structures. In our work we use irradiation of complex biological molecules with high density green photons, which may induce electric dipoles by polarization effects. The resulting dipolar interaction may lead to organized structures like molecular aggregates and microparticles. We present experimental evidence of such an optical manipulation on long alkanes chains and two specific enzymes. A preliminary physical model is suggested for acounting of these specific interaction forces.