METHODS AND TECHNOLOGIES OF BIOMEDICAL RESEARCH
Artificial membrane structures containing medicinal substances are highly promising for the development of new drugs. Liposomal preparations are actively used in medical practice due to their high efficacy and relatively low toxicity. Our aim was to encapsulate anti-idiotypic antibodies into a liposomal composition with the purpose of improving their immunogenic properties. Following the preparation of a liposomal composition by the dehydration/rehydration method using ultrasonic treatment, the size, zeta potential, and loading efficiency of liposomes were investigated. Preliminary in vivo studies were conducted to evaluate the adjuvant properties of liposomes of varying size. Loaded liposomes of the smallest diameter (about 110 nm) showed the potential of enhancing the immune response similar to that obtained using Freund’s adjuvant. These results justify further research into the properties of liposomes loaded with antibodies.
In order to preserve and increase the biological effectiveness of biologically active substances isolated from deer musk, we studied technological aspects of obtaining a substance of lipid-stabilized stable nanoparticles from deer musk. The stability of the obtained substance was evaluated. It was found that homogenization under high pressure is an optimal approach to obtaining biologically active substances from deer musk. The modes of preparation of a liposomal form of biologically active substances with predetermined dispersion parameters (average particle diameter 250 ± 100 nm, polydispersity index 0.3 ± 0.1, and zeta potential from -5 to -35 mV) were determined. It was found that the high-pressure homogenizer “Donor-5” makes it possible to obtain liposomal dispersions with standard parameters and the degree of inclusion of musk biologically active substances up to 60%, at the same time as providing minimal oxidation and hydrolysis of phospholipids (oxidation index 0.3). Our studies showed that the use of a domestic phosphatidylcholine is economically justified and allows obtaining liposomal forms of proper quality. The quality indicators of the obtained liposomal substance were characterised by conventional analytical methods (dynamic light scattering, electron microscopy, gel chromatography, chromatography-mass spectrometry, etc.). On the basis of the results obtained, a draft specification was developed for a liposomal substance (powder) containing a complex of biologically active substances isolated from deer musk. The developed technology for obtaining a liposomal form of biologically active substances from deer musk can be scaled up in accordance with GMP requirements.
Velvet antler products are adaptogens of animal origin, capable of increasing the physical and mental capacity of the body. It is known that the velvet antler products based the maral blood and a histolysate obtained from the genitals of males exhibit a more pronounced revitalizing effect. Experiments were conducted on 40 mature white male Wistar rats weighing 230±20 g, divided into 3 groups: intact group (n=20); control group (n=10); experimental group (n=10). The experimental group received a concentrate Pantohematogen (Lubyan’gem) at a dose of 2 ml per 100 g of body weight for 30 days; the control group – an aqueous solution of concentrate additives; the intact animals – water in the same volume. On the 31st day of the experiment, the microcirculation indicators of all animals were studied by laser doppler flowmetry. In comparison with intact animals, the rats of the experimental group receiving the concentrate for 30 days showed an increase in the blood flow modulation by 108% (p=0.006), in the amplitude of endothelial fluctuations by 71% (p=0.006), and in the amplitude of vasomotor waves by 45% (p=0.024). This indicates an intensification of the “active” mechanisms of microcirculation regulation.
One of the main problems of modern medicine is cancer, which is the second leading cause of death after cardiovascular disease. Malignant neoplasms have been known for a long time; however, their study still presents significant difficulties. Modeling of malignant processes in animals allow researchers to study tumors and the main patterns of malignant growth characteristic of animals and humans. The main cause of death in malignant neoplasms is the process of metastasis formation, which remains to be understood in detail. The study of metastatic processes is one of the most important tasks of oncology. To this end, various models of tumor metastasis are created. The article reviews literature data on the most popular models of metastasis in experimental conditions. The advantages and disadvantages of the main approaches to modeling metastasis are evaluated.
NON-CLINICAL RESEARCH IN BIOMEDICINE
The qualitative composition of phenolic acids and burn wound healing activity of Prunella grandiflora L. extract were studied. The content of rosmarinic (621±5 mg/g), coffeic (11.2±0.2 mg/g), syringic (46.5±1.4 mg/g), n-coumaric (25.8±0.5 mg/g), and ferulic (42.7±2.9 mg/g) acids in dry extracts of P. grandiflora was determined by HPLC. Three new burn-healing agents of different composition containing 5% of the dry extract of Prunella grandiflora L. (big-flowered self-heal) were developed. The developed agents were tested on male Wistar rats with second- and third-degree thermal burns. An assessment of skin restoration was carried out in experimental and control groups of animals. It was revealed that animals treated with the developed soft dosage forms restored the epithelium and coat 6–8 days faster that those treated with compositions containing no extract under study. It was found that the developed soft dosage forms based on P. grandiflora extract exhibit anti-inflammatory and wound-healing action.
This works aims to study morphofunctional changes in the vessels of the oral mucosa during regeneration of a wound defect with and without a polymer membrane.
An experiment was carried out on 35 white Wistar rats divided into three groups: control, experimental 1 and experimental 2. To form a wound defect, a flap of the oral mucosa was excised, which was covered by a polymeric piezoelectric membrane in the rats of group 2. Histological examination was carried out on the 3rd, 7th and 12th days: the control material was taken, histological preparations were made according to the standard method. In the lesion focus and surrounding tissues, specific areas and numerical densities of arterioles, venules and capillaries were determined; the pericapillary diffusion index, Kernogan index and arterio-venular ratio were calculated.
On the 3rd day, all indicators in all experimental groups did not significantly differ from each other, but had significant differences from the control group. On the 7th day of the study, in the 1st group, the numerical density of open arterioles and venules corresponded to the control group. In group 2, the numerical density of capillaries and altered venules, as well as the index of pericapillary diffusion, significantly differed from the control. On the 12th day of the study, the numerical density of open venules reached control values in the uncoated group. In the 2nd group, all indicators corresponded to the control values.
Protection of the wound defect from microbial contamination and re-traumatization, the presence of piezoelectric properties of the membrane under study contributed to a more effective restoration of vessels. This confirms the efficacy of the membrane under study when used as a wound covering.
This study aims to assess the specific toxicity (allergenicity, immunotoxicity and reproduction toxicity) of a dosage form of complement C3 neodeterminant recombinant humanized antibody. The reactions of general anaphylaxis, active cutaneous anaphylaxis and delayed-type reaction demonstrated no drug-related signs of experimental animal sensitization and immediate or delayed hypersensitivity in the treated animals. It was found that, in doses exceeding significantly the expected human therapeutic dose, the drug has no effect on humoral and cell-mediated immune responses. In addition, the drug does not suppress the phagocytic cell activity thereby indicating the absence of immunotoxic effect. Moreover, the drug has no adverse effects on male and female reproduction, progeny embryonal development, as well as prenatal and postnatal progeny development. The obtained data can be used in future clinical studies of the drug safety.
ISSN 2713-0428 (Online)