Bulletin of Experimental Biology and Medicine最新文献

The species identity of the studied lactobacillus strains was confirmed by matrix-activated laser desorption/ionization with time-of-flight ion separation (MALDI-TOF mass spectrometry). Lactobacillus strains differed in the dynamics of lactic acid accumulation and changes in the pH of the culture medium. The culture medium affected adhesion ability of lactobacilli. The ability to adhere does not affect the formation of biofilms by lactobacillus strains except for the L. acidophilus La5 strain, which has low adhesion ability and fewer microbial cells detected after mechanical destruction of the biofilm. The metabiotics of the lactobacillus culture medium have an antagonistic effect on conditionally pathogenic microorganisms. Adhesion, biofilm formation, and antagonistic activity of probiotic lactobacillus strains are strain-specific properties.

A new gene-cell construct expressing nerve growth factor (NGF) has been developed. After obtaining engineered adenovectors Ad5-RGD-CAG-NGF and Ad5-RGD-CAG-EGFP, transduction efficiency and transgene expression were studied and multiplicity of infection was determined. The efficacy of transduced human olfactory ensheathing cells expressing NGF in restoring motor activity in rats has been shown in a limited period of time. Improved rat hindlimb mobility and cyst size reduction after gene-cell construct transplantation were more likely due to the cellular component of the construct.

The review considers the use of exogenous neurotrophic factors in the treatment of neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and others. This group of diseases is associated with the death of neurons and dysfunction of the nervous tissue. Currently, there is no effective therapy for neurodegenerative diseases, and their treatment remains a serious problem of modern medicine. A promising strategy is the use of exogenous neurotrophic factors. Targeted delivery of these factors to the nervous tissue can improve survival of neurons during the development of neurodegenerative processes and ensure neuroplasticity. There are methods of direct injection of neurotrophic factors into the nervous tissue, delivery using viral vectors, as well as the use of gene cell products. The effectiveness of these approaches has been studied in numerous experimental works and in a number of clinical trials. Further research in this area could provide the basis for the creation of an alternative treatment for neurodegenerative diseases.

The morphometric characteristics of brain tissue were studied based on autopsy material from 49 deceased newborns divided into 7 groups based on the time after death. Samples were taken from the upper (frontal lobe) and lower (occipital lobe) regions relative to the supine position of the body. Paraffin sections were prepared from these samples and stained with hematoxylin and eosin. Histological preparations were analyzed using an image analysis system to determine the area of gliocyte nuclei, cross-cut blood vessels, and expanded area around them in the white matter of the brain. Based on these data, severity indices were calculated for both cellular (pericellular) and vascular (perivascular) expansion. The dynamics of changes in morphometric parameters within the range of cellular and vascular alterations on brain tissue specimens, which reflect the development of postmortem hypostasis and autolysis in this organ, can be used to estimate the duration of the postmortem interval. At the same time, these changes, when combined with other non-specific postmortem findings, should be distinguished from long-term pathological processes and diseases that may have occurred during life.

We studied the effect of a high-fat, high-carbohydrate diet (HFHCD) on basal testosterone levels in the blood and testosterone, its precursors, and expression of steroidogenic genes in the testes of rats treated with human chorionic gonadotropin (hCG, 10 IU/rat, subcutaneously, once), gonadotropin-releasing hormone receptor antagonist cetrorelix (75 μg/kg, subcutaneously, 3 days), and their combination. In HFHCD rats, no obvious signs of androgen deficiency were observed and the response of the testes to hCG stimulation was preserved. Unlike control rats (normal diet), the expression of the luteinizing hormone receptor gene in these rats did not change in response to hCG stimulation and cetrorelix administration; they also showed a paradoxical, more pronounced response to hCG administration under conditions of suppression of the gonadotropin secretion by cetrorelix. This suggests that the etiology and pathogenesis of obesity may have different effects on the hormonal status of the male reproductive system.

We demonstrated that the serum of pregnant rats increases viability of kidney epithelial cells and promotes their proliferation. The intensity of oxidative stress in the kidneys was also reduced during pregnancy, but only in rats that were not exposed to acute ischemic kidney injury. This decrease in oxidative stress was not associated with changes in transmembrane mitochondrial potential, the size of mitochondria, time of opening of mitochondrial permeability transition pore (mPTP), mitochondrial respiration rate, antioxidant activity, or nitric oxide level.

Two bacteriophages specifically active against to pathogenic strains of the Salmonella genus were isolated. The morphology of phage colonies (size, transparency, and shape of the plaque edge, and halo) and the spectrum of their lytic activity and interaction with microbial cells (adsorption rate, duration of the latency, and reproductive efficiency) were examined. Using genome-wide sequencing, we determined the taxonomic position of bacteriophages and verified the absence of unwanted genes encoding toxins, adhesins, and invasins, as well as pathogenicity islands responsible for antibiotic resistance. In addition, phage stability under different physical conditions and their productivity were studied.

A comparative analysis of morphological and functional changes in the adrenal glands after embolization of supplying arteries with Lifepearl microspheres (100±25 μm; Terumo) and with a solution of polidocanol (Aethoxysklerol, Kreussler Pharma) was performed in male Vietnamese Lop-Bellied pigs (n=20). The introduction of the microspheres into the arterial bed did not affect the adrenal parenchyma. However, the injection of the liquid sclerosing agent caused foci of productive inflammation leading to the formation of sclerotic tissue and reduction of the volume of glandular tissue. Administration of the sclerosant was accompanied by arterial hypotension, an indirect indication of a decrease in vasoactive hormone production by the adrenal cortex. These findings suggest that polidocanol can be used as an embolization agent for hyperplastic diseases of the adrenal cortex.

The effect of polysaccharides isolated from the aboveground parts of Saussurea salicifolia (L.) DC on Th2 type immune response reactions was studied. Administration of water-soluble polysaccharides presented by arabino-galacturonans (weight average molecular weight 158.49 kDa) to mice against the background of experimental Th2 immunity reduced the severity of anaphylactic and local immediate type hypersensitivity reactions. It also suppressed the production of ovalbumin-specific IgE and IgG1 and increased the stability of mast cell membranes. The studied polysaccharide complex increased IFNγ secretion and inhibited IL-4 synthesis. These findings suggest that these polysaccharides may be considered as potential anti-allergic agents that suppress the development of allergy in its early stages.

We studied the influence of metabolites of permafrost microorganisms obtained at different temperature incubation conditions on activity of differentiation of regulatory (Treg) and effector T lymphocytes. It was found that the effect of metabolites is largely regulated by their type that depends on the temperature of production (“cold” at 5°C, “medium temperature” at 22°C, and “warm” at 37°C). The studied metabolites influenced the differentiation of Tregs (CD4⁺CD25^hiCD127^—) and the expression of markers of early (CD69), middle (CD25), and late (HLA DR) activation of CD4⁺ and CD8⁺ T lymphocytes. In the case of “cold” metabolites, the increase in Treg levels was associated with a decrease in the intensity of CD4⁺ T lymphocyte differentiation, and under the influence of “warm” metabolites — with a decrease in the activity of CD8⁺ T lymphocyte differentiation. Under the influence of “medium-temperature” metabolites, Tregs had approximately the same effect on the intensity of CD4⁺ and CD8⁺ T lymphocyte differentiation.