The source of X-rays and high-charged ions based on moderate power vacuum discharge with laser triggering

The source of X-ray radiation with the energy of quanta that may vary in the range hν = 1÷12 keV was developed for studies in X-ray interaction with matter and modification of solid surfaces. It was based on a vacuum spark discharge with the laser triggering. It was shown in our experiments that there is a possibility to adjust X-ray radiation spectrum by changing the configuration of the electrode system when the energy stored in the capacitor is varied within the range of 1÷17 J. A comprehensive study of X-ray imaging and quanta energy was carried out. These experiments were carried out for the case of both direct and reverse polarity of the voltage on the electrodes. Additionally, ion composition of plasma created in a laser-triggered vacuum discharge was analyzed. Highly charged ions Zn(+21), Cu(+20) and Fe(+18) were observed

Influence of serotonin transporter allele polymorphism on individual characteristics of cerebral hemodynamics in humans under the "Stop-Signal" experimental paradigm

The influence of polymorphic variations of the gene encoding serotonin transporter (5-HTT) on individual characteristics of cerebral hemodynamics (detected by means of functional magnetic resonance imaging (fMRI) under conditions of the performance of the tasks of the “Stop–Signal” experimental paradigm) was studied in the work. The 5-HTT gene polymorphic variants were determined by means of allelespecific PCR with DNA isolated from the blood of subjects as a matrix. Altogether, 24 subjects (eight individuals with the LL genotype, eight with the LS genotype, and eight with the SS genotype) were studied. In the experiments, the subjects either push a button after the appearance of a target stimulus (Go condition) or suppressed already prepared movement (Stop condition). Differences associated with the genotype were observed in hemodynamic responses registered in areas of the cuneus (occipital lobe of the cerebral cortex), as well as medial frontal and inferior frontal gyri (frontal lobes of the cerebral cortex). The SS genotype carriers demonstrated a significantly larger contrast between fMRI responses under Go and Stop conditions as compared with the LL and LS genotype carriers (which can be interpreted as an index of a greater intensity of the activation processes in them and a decreased capacity for the suppression of inadequate movements). Theoretically, individuals with the SS genotype have an advantage over individuals with LL and LS genotypes when making a decision with a lack of time; however, they deal worse with situations requiring the suppression of inadequate behavioral responses

Influence of serotonin transporter allele polymorphism on individual characteristics of cerebral hemodynamics in humans under the "Stop-Signal" experimental paradigm

The influence of polymorphic variations of the gene encoding serotonin transporter (5-HTT) on individual characteristics of cerebral hemodynamics (detected by means of functional magnetic resonance imaging (fMRI) under conditions of the performance of the tasks of the “Stop–Signal” experimental paradigm) was studied in the work. The 5-HTT gene polymorphic variants were determined by means of allelespecific PCR with DNA isolated from the blood of subjects as a matrix. Altogether, 24 subjects (eight individuals with the LL genotype, eight with the LS genotype, and eight with the SS genotype) were studied. In the experiments, the subjects either push a button after the appearance of a target stimulus (Go condition) or suppressed already prepared movement (Stop condition). Differences associated with the genotype were observed in hemodynamic responses registered in areas of the cuneus (occipital lobe of the cerebral cortex), as well as medial frontal and inferior frontal gyri (frontal lobes of the cerebral cortex). The SS genotype carriers demonstrated a significantly larger contrast between fMRI responses under Go and Stop conditions as compared with the LL and LS genotype carriers (which can be interpreted as an index of a greater intensity of the activation processes in them and a decreased capacity for the suppression of inadequate movements). Theoretically, individuals with the SS genotype have an advantage over individuals with LL and LS genotypes when making a decision with a lack of time; however, they deal worse with situations requiring the suppression of inadequate behavioral responses

Heavily Gd-Doped Non-Toxic Cerium Oxide Nanoparticles for MRI Labelling of Stem Cells

Recently, human mesenchymal stem cells (hMSc) have attracted a great deal of attention as potential therapeutic agents in the treatment of socially significant diseases. Despite substantial advances in stem-cell therapy, the biological mechanisms of hMSc action after transplantation remain unclear. The use of magnetic resonance imaging (MRI) as a non-invasive method for tracking stem cells in the body is very important for analysing their distribution in tissues and organs, as well as for ensuring control of their lifetime after injection. Herein, detailed experimental data are reported on the biocompatibility towards hMSc of heavily gadolinium-doped cerium oxide nanoparticles (Ce0.8Gd0.2O2−x) synthesised using two synthetic protocols. The relaxivity of the nanoparticles was measured in a magnetic field range from 1 mT to 16.4 T. The relaxivity values (r1 = 11 ± 1.2 mM−1 s−1 and r1 = 7 ± 1.2 mM−1 s−1 in magnetic fields typical of 1.5 and 3 T MRI scanners, respectively) are considerably higher than those of the commercial Omniscan MRI contrast agent. The low toxicity of gadolinium-doped ceria nanoparticles to hMSc enables their use as an effective theranostic tool with improved MRI-contrasting properties

Heavily Gd-Doped Non-Toxic Cerium Oxide Nanoparticles for MRI Labelling of Stem Cells

Recently, human mesenchymal stem cells (hMSc) have attracted a great deal of attention as potential therapeutic agents in the treatment of socially significant diseases. Despite substantial advances in stem-cell therapy, the biological mechanisms of hMSc action after transplantation remain unclear. The use of magnetic resonance imaging (MRI) as a non-invasive method for tracking stem cells in the body is very important for analysing their distribution in tissues and organs, as well as for ensuring control of their lifetime after injection. Herein, detailed experimental data are reported on the biocompatibility towards hMSc of heavily gadolinium-doped cerium oxide nanoparticles (Ce0.8Gd0.2O2−x) synthesised using two synthetic protocols. The relaxivity of the nanoparticles was measured in a magnetic field range from 1 mT to 16.4 T. The relaxivity values (r1 = 11 ± 1.2 mM−1 s−1 and r1 = 7 ± 1.2 mM−1 s−1 in magnetic fields typical of 1.5 and 3 T MRI scanners, respectively) are considerably higher than those of the commercial Omniscan MRI contrast agent. The low toxicity of gadolinium-doped ceria nanoparticles to hMSc enables their use as an effective theranostic tool with improved MRI-contrasting properties