Comparative Analysis of the Different Dyes' Potential to Assess Human Normal and Cancer Cell Viability In Vitro under Different D/H Ratios in a Culture Medium.

In this study, using new approach (laser diffraction + biological dyes), we have demonstrated the decrease of cells viability in vitro in the deuterated growth medium, whereas in the deuterium-depleted medium, there was an increase of cell viability. We have also found that not all dyes are equally sensitive to the D/H ratios in the culture medium (system) as well as to the different cell types (cancer vs normal cells).

Mechanical Transformation of Compounds Leading to Physical, Chemical, and Biological Changes in Pharmaceutical Substances.

This study demonstrates the link between the modification of the solid-phase pharmaceutical substances mechanical structure and their activity in waters with different molar ratio «deuterium-protium¼. Mechanochemical transformation of the powders of lactose monohydrate and sodium chloride as models of nutrients and components of dosage forms was investigated by the complex of physicochemical and biological methods. The solubility and kinetic activity of substances dispersed in various ways showed a positive correlation with the solvent isotope profile. Substances dissolved in heavy water were more active than solutes in natural water. Differential IR spectroscopy confirmed the modification of substituents in the sample of lactose monohydrate, demonstrating physicochemical changes during mechanical intervention. The biological activity of the compounds was determined by the method of Spirotox. The activation energy was determined by Arrhenius. Compared with the native compound, dispersed lactose monohydrate showed lower activation energy and, therefore, greater efficiency. In conclusion, proposed data confirm the statement that mechanical changes in compounds can lead to physicochemical changes that affect chemical and biological profiles.

The DNA of Bacteria of the World Ocean and the Earth in Cosmic Dust at the International Space Station.

Cosmic dust samples from the surface of the illuminator of the International Space Station (ISS) were collected by a crew member during his spacewalk. The sampler with tampon in a vacuum container was delivered to the Earth. Washouts from the tampon's material and the tampon itself were analyzed for the presence of bacterial DNA by the method of nested PCR with primers specific to DNA of the genus Mycobacteria, DNA of the strains of capsular bacteria Bacillus, and DNA encoding 16S ribosomal RNA. The results of amplification followed by sequencing and phylogenetic analysis indicated the presence of the bacteria of the genus Mycobacteria and the extreme bacterium of the genus Delftia in the samples of cosmic dust. It was shown that the DNA sequence of one of the bacteria of the genus Mycobacteria was genetically similar to that previously observed in superficial micro layer at the Barents and Kara seas' coastal zones. The presence of the wild land and marine bacteria DNA on the ISS suggests their possible transfer from the stratosphere into the ionosphere with the ascending branch of the global electric circuit. Alternatively, the wild land and marine bacteria as well as the ISS bacteria may all have an ultimate space origin.

The effect of the deuterium depleted water on the biological activity of the eukaryotic cells.

Here we show the dependence of the unicellular biosensor S.ambigua lifespan on the water D/H isotopic composition. This dependence is bell-shaped with descents both in case of deficiency or excess of deuterium in water. The influence of the water D/H isotopic composition on the cell culture proliferative potential and colony forming efficiency in vitro was tested on the human dermal fibroblasts. We observed that the deuterium depleted water stimulates cell colony formation at the early passages. The dynamics of the cell doubling index in the deuterium depleted water-based growth medium showed higher proliferation potential compared to the water with normal isotopic composition. Using scratch assay, we have also studied the impact of the growth medium D/H isotopic composition on the cell motility of human cancer cell lines A549 and HT29. We have shown that the deuterium depleted water considerably suppressed cancer cell lines amoeboid movement in vitro.