An Innovative Methodology to Characterize, at the Molecular Scale, Interactions in Polysaccharide Aqueous Solutions.

Characterizing molecular interactions at the microscopic level remains difficult and, therefore, represents a key target to better understand macromolecule and biomacromolecule behaviors in solution, alone, or in mixtures with others. Therefore, accurate characterization in liquid media, especially in aqueous solutions, without causing any perturbation of the system in which they are studied, is quite difficult. To this purpose, the present paper describes an innovative methodology based on fluorescence spectrophotometry.

The Synthesis and Transfection Activity of Disulfide Polycationic Amphiphiles.

Some new polycationic amphiphiles containing a disulfide group were synthesized. Cationic liposomes formed from the compounds synthesized and a helper lipid 1,2-dioleoyl--glycero-3-phosphatidylethanolamine were not toxic for HEK293 and HeLa cells and were highly effective when delivering a fluorescently labeled oligodeoxyribonucleotide. The efficacy of plasmid DNA delivery depended on the cell line and the amphiphile structure, liposomes based on tetracationic amphiphiles being the most effective transfectants.

Being present in a real or virtual world: A EEG study.

Background And Objective: This study proposes an approach to evaluation and measuring of presence for man-machine interaction in the virtual reality based on electroencephalographic data.

Materials And Methods: It analyzes stable electroencephalographic patterns that allow us to trace a connection between a brain activity and purposeful actions of an individual in various environments. The subjects of the study were experienced downhill skiers equipped with electroencephalographs, who performed real-life skiing on a downhill course, after which they were offered a virtual simulation of downhill skiing using an HTCVive headset and a programmed 2D or desktop simulator.

Study of the time of the visual system recovery.

The time of the visual system recovery was studied. The experimental method is presented. The results confirm a relationship between the duration of the threshold interval between pulses and the duration of light pulses.

Novel cationic liposomes provide highly efficient delivery of DNA and RNA into dendritic cell progenitors and their immature offsets.

Here we report on the application of cationic liposomes formed by new cationic lipids and the lipid-helper DOPE (dioleoylphosphatidylethanolamine) for the transfection of plasmid DNA and mRNA into dendritic cells (DCs) progenitors and immature DCs of bone-marrow origin in vitro and the use of these DCs to induce the suppression of B16 melanoma metastases in vivo. The cationic lipids contain one (X2, S1, S2 and S3) or two (2X3) cholesterol residues or long-chain hydrocarbon substituent (2D3) linked with spermine. Data show that liposomes 2X3-DOPE, 2D3-DOPE, X2-DOPE and S2-DOPE display high transfection efficiency in respect to DNA (30-47% of DC progenitors and up to 57% of immature DC were transfected) and RNA (up to 57% of cells were transfected).

Novel cholesterol spermine conjugates provide efficient cellular delivery of plasmid DNA and small interfering RNA.

New polycationic lipids corresponding to the two different classes of amphiphiles ("head-tail" and "gemini") were designed and used as components of non-viral gene delivery systems. The hydrophobic domain of lipids is based on the cholesterol residue and the hydrophilic one--on the naturally occurring polyamine--spermine. Ester and carbamate linker groups as well as oligomethylene spacers of various lengths were used to connect cholesterol and spermine motifs in order to estimate the structure-activity relationships of novel polycationic lipids and to determine an effective and safe transfectant suitable for the delivery of different nucleic acids.

On the accuracy of evaluations of temporal characteristics of visual perception.

We studied the accuracy of evaluations of the temporal characteristics of visual perception: critical frequency of light flickers, time of perception, and time of visual analyzer recovery. Results of comparison of the accuracy of evaluations are presented.

[Thrombocytic component of hemostasis in patients operated on for acute inflammatory diseases of the abdominal organs].

Thrombocytopathy in the form of dissociation of functional properties of the thrombocytes was revealed in patients with purulent appendicitis. Patients with restricted peritonitis had an increased amount of thrombocytes, activation of their functions, changes in the thrombocyte formula, different correlative interrelations between the size of thrombocytes and their properties.

[New approaches to the surgical treatment of coronary arteriosclerosis].

A new combined approach to surgical treatment of coronary heart disease is recommended: direct myocardial revascularization (mammary-coronary and aorto-coronary bypass) to recover coronary flow; partial ileo-shunting to control hyperlipoproteinemia, and Arnulf's plexectomy (heart denervation) to eliminate vasospastic component. The sequence of operations can be altered depending on the diagnostic findings. Each operation can be performed independently or in combination with others.

[Revascularization of the left side of the heart using splenocoronary anastomoses].

An original technique developed by the authors was used in 51 experiments on dogs. Under study were the ECG-dynamics, the volume of the retrograde bloodflow and blood pressure in the splenic and anterior interventricular arteries before and after creating the retrograde spleno-coronary anastomosis. The results of studies of hemodynamics at this operation have confirmed its physiological adequacy.

[Retrograde mammary-coronary anastomosis and its place among other methods of myocardial revascularization].

Under consideration is a special kind of mammary-coronary anastomosis--a retrograde mammary-coronary anastomosis, first suggested by the authors. An anteretrograde mammary-coronary anastomosis was performed in 104 patients, a retrograde one--in 6. The use of a retrograde mammary-coronary anastomosis yielded favourable results, which in some cases are remained for 4-5 years.