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Vol 24, No 1 (2024)
- Year: 2024
- Articles: 10
- URL: https://bakhtiniada.ru/MAJ/issue/view/17037
- DOI: https://doi.org/10.17816/MAJ.11
Analytical reviews
Epileptic activity or eeg similar to epileptic activity. How to recognize? Review
Abstract
The review examines the recently accumulated clinical and experimental data on the mechanisms of epileptogenesis, and the most appropriate methods for recording an electroencephalogram to detect epileptiform activity. A description of epi-patterns is provided, as well as artifacts – graph elements similar to epi-patterns. All descriptions are supported by appropriate illustrations. In order to identify possible epi-activity, the need for preliminary registration of electroencephalogram with functional tests in the form of rhythmic photostimulation and hyperventilation for a person participating as a subject in studies related to physical and postural loads is emphasized.
5-22
Molecular diagnostics of familial hypercholesterolemia in Russia: yesterday, today and tomorrow
Abstract
Familial hypercholesterolemia is a severe hereditary disease leading to the development of atherosclerosis and its complications in the form of angina pectoris, myocardial infarction, cerebral stroke, or even leading to sudden death. Since the description of the disease, the concept of it has undergone significant evolution. First, it became clear that the prevalence of this disease was significantly higher than originally thought (1:300 for heterozygous familial hypercholesterolemia and not as 1:500 as estimated earlier). Secondly, it has been established that it is not based on the pathology of the low-density lipoprotein receptor gene alone, but includes at least four monogenic forms (defects of the APOB, PCSK9, ARH genes) and may also have a multigenic nature. Thirdly, with the development of DNA analysis methods from the initially available Southern hybridization to next generation DNA sequencing, the exceptional molecular heterogeneity of familial hypercholesterolemia became obvious and, accordingly, the need to establish national spectra of mutations leading to the development of familial hypercholesterolemia was established. Researchers have moved from characterizing individual mutations to creating national registries and databases. Finally, research into the genetics of familial hypercholesterolemia has led to the emergence of new classes of cholesterol-lowering drugs. In Russia, molecular diagnostics of familial hypercholesterolemia has also undergone significant changes since the beginning of the study of familial hypercholesterolemia in 1987 and to the present, consideration of these changes formed the basis of this review.
23-36
Glutamate decarboxylase and its isoforms
Abstract
The review summarizes current data on the properties, localization and physiological role of GABA synthesizing enzyme, glutamic acid decarboxylase, in mammalian tissues. Due to the high prevalence of the enzyme in the body’s cells and tissues, at the moment there is a large array of scattered experimental data, which needs to be processed and systematized. Presented data demonstrate the involvement of glutamate decarboxylase in different biochemical and physiological processes of the body. It has been demonstrated that the role of enzyme as the major component of the GABAergic neurotransmission in the central nervous system is the most intensively studied. However, there is only limited information regarding distribution and functional role of glutamate decarboxylase in the peripheral nervous system, and therefore requires additional research.
37-50
Main scientific achievements of the academician of the RAS Vladimir Kh. Khavinson: peptides and aging
Abstract
The article is dedicated to the memory of the outstanding Russian gerontologist, director of the Saint Petersburg Institute of Bioregulation and Gerontology, academician of the Russian Academy of Sciences, professor Vladimir Kh. Khavinson.
51-58
Involvement of interferon-gamma and tumor necrosis factor-alpha in the formation of unstable atherosclerotic plaque
Abstract
Research on the role of various interleukins in atherosclerosis has shown that pro-inflammatory cytokines contribute to disease progression and destabilization of atherosclerotic plaques. The review presents the latest data from the scientific literature and the study’s own findings on the effects of pro-inflammatory cytokines INF-γ and TNF-α on the formation of unstable atherosclerotic lesions. It has been shown that the deterioration of the unstable plaque cap strength and its destruction can be associated with an increase in concentration, activation and action of powerful pro-inflammatory cytokines INF-γ and TNF-α in the vascular wall.
59-66
Transthyretin amyloidosis. Fundamentals of pathogenesis, diagnosis, treatment, prognosis
Abstract
Among the 42 human amyloidoses described to date the so-called systemic transthyretin amyloidosis, which comprises hereditary forms (more than 140 variants in accordance with the number of identified mutations in the transthyretin gene) and a sporadic form without structural changes in the gene and the protein, is of particular interest. This review summarizes modern understandings of pathogenesis of transthyretin amyloidosis. The symptoms of different forms of transthyretin amyloidosis, issues of early diagnosis, differential diagnosis (including within the group of amyloidoses), advanced therapy and prognosis are considered. Special attention is given to the non-mutant form of transthyretin amyloidosis, the so-called senile amyloidosis, which significantly complicates the course of underlying pathologies in the age group older than 70 years and is still poorly diagnosed. A quite high occurrence of non-mutant form of transthyretin amyloidosis makes it to be considered as a socially significant disease.
67-82
Original research
Effect of nystatin on invasion of Serratia grimesii and Serratia proteamaculans bacteria into epithelial cells
Abstract
BACKGROUND: Bacteria use various endocytic pathways during entering non-phagocytic cells. The involvement of caveolae/lipid rafts in bacterial invasion has been demonstrated for many bacterial pathogens. However, for bacteria of the genus Serratia, the involvement of membrane microdomains in the process of bacterial internalization has been poorly studied.
AIM: To evaluate the involvement of caveolae/lipid rafts in the invasion of S. grimesii and S. proteamaculans bacteria into non-phagocytic epithelial Caco-2 and M-HeLa cells using nystatin.
MATERIALS AND METHODS: M-HeLa and Caco-2 epithelial cells were incubated with 50 μM nystatin for 1 hour at 37 ºC, after which they were infected with the bacteria S. grimesii strain 30063 and S. proteamaculans strain 94, the multiplicity of infection was 100 bacteria per cell. The number of intracellular bacteria was assessed using gentamicin protection assay. The level of caveolin-1 in cells was visualized using confocal microscopy and Western blotting. The expression of Toll-like receptors genes were measured by real-time RT-PCR.
RESULTS: Treatment of epithelial cells with nystatin reduces the internalization of S. grimesii and S. proteamaculans into M-HeLa cells by 30% and does not affect penetration into Caco-2 cells. At the same time, nystatin does not affect the redistribution / the integrity impairment of lipid rafts and does not lead to the cytoskeleton reorganization of eukaryotic cells. The addition of nystatin increases the level of caveolin-1 in M-HeLa cells (caveolin-1 is not expressed in Caco-2), which leads to a change plasma membrane fluidity. Nystatin promotes the secretion of proinflammatory cytokines interleukin-6 and interleukin-8 in both cell lines. Infection of M-HeLa cells pretreated with nystatin with the studied bacteria leads to an increase in the expression of tlr2 and tlr4 genes, but does not exceed the level of their expression in control samples. Therefore, it is impossible to speak unambiguously about the participation of Toll-like receptors in the invasion of Serratia bacteria.
CONCLUSIONS: The results obtained suggest that the interaction of bacteria with eukaryotic cells induces the expression of caveolin-1, which leads to a change plasma membrane components mobility. This may be due to the fact that β1-integrin is involved in the invasion of the studied bacteria, which should be stabilized at the plasma membrane upon binding of the ligand due to the formation of a cholesterol- and sphingolipid-rich membrane microenvironment.
83-96
Changes in the liver of Djungarian hamsters under conditions of a three-month supply of water-soluble silicon of various concentrations
Abstract
BACKGROUND: Silicon enters the human body through drinking water, air and food. Silicon nanoparticles used in the cosmetic, pharmaceutical and food industries are known to have biological activity. Taking into account the widespread prevalence of silicon compounds, the issue of the safety of its use is becoming more urgent.
AIM: To study the effect of water-soluble silicon on the morphological structure of the liver of Djungarian hamsters for three months.
MATERIALS AND METHODS: The experiment was carried out on Djungarian hamsters kept in normal vivarium conditions under natural light. The animals were divided into three groups: control, which received bottled drinking water; the first experimental group, which received the same water, but with the addition of sodium metasilicate nine-hydrate at a concentration of 10 mg/l in terms of silicon; the second experimental group, which also received the same water, but with the concentration of sodium metasilicate nine-hydrate doubled (up to 20 mg/l). After three months, the animals were removed from the experiment. Sections were processed by general histological (hematoxylin and eosin, Van Gieson method, toluidine blue), histochemical (monoamine oxidase-positive cells) methods.
RESULTS: In the liver of hamsters from the experimental groups, changes in the micromorphological structure were revealed, such as an increase in the nuclear area, nuclear-cytoplasmic ratio of hepatocytes, and the diameter of sinusoidal capillaries. Moreover, more pronounced changes were observed in the liver of hamsters of the second experimental group, such as polymorphic cell infiltration of the portal tracts, an increase in the number of eosinophils, deformation of hepatocyte nuclei and the appearance of apoptotic bodies. A decrease in the area of mast cells and an increase in their number, as well as the number of monoamine oxidase-positive cells in the liver of hamsters of both experimental groups were recorded.
CONCLUSIONS: An increase in the concentration of silicon supplied with drinking water in both cases is reflected in the micromorphological structure of the liver of hamsters. Moreover these changes are more pronounced in the liver of hamsters of the second experimental group.
97-106
Gap junction protein connexin 43 and its distribution in damaged nerve cells
Abstract
BACKGROUND: Connexins, particularly connexin 43, form gap junctions that mediate neuron-glial communication. To date, the expression of connexin 43 in phenotypically distinct neurolemmocytes, in particular non-myelinating (Remak cells) and repair Schwann cells, has not been studied.
AIM: To determine the presence of connexin 43 in Schwann cells of the rat sciatic nerve under normal conditions and after mechanical damage by applying a ligature.
MATERIALS AND METHODS: The study was carried out on Wistar rats (n = 10). In experimental rats, the sciatic nerve was damaged by applying a ligature (40 s). 7 days after surgery, sciatic nerve segments were isolated for subsequent immunohistochemical study using antibodies to connexin 43 and glial fibrillary acidic protein (GFAP). In the control group rats, segments of intact sciatic nerves were isolated in a similar way.
RESULTS: It has been shown that in the endoneurium of the intact rat sciatic nerve there are no cells expressing connexin 43. It was found that 7 days after injury, a large number of connexin-43-immunopositive cells of irregular shape with several processes were identified in the endoneurium of the damaged nerve. There was a lack of expression of connexin 43 in GFAP-containing Schwann cells.
CONCLUSIONS: It can be stated that nerve damage leads to active synthesis of the studied protein by endoneurium cells; however, the origin of the cells expressing connexin 43 remains to be elucidated.
107-116
Chronicle
Regulatory cytokine network and macrophages (in memory of Irina S. Freidlin)
Abstract
Irina S. Freidlin was an outstanding Soviet and Russian immunologist, Doctor of Medical Sciences, Professor, Honored Scientist, Corresponding Member of the Russian Academy of Sciences. She was a natural for teaching and a deep scientific researcher whose interests were mainly related to the study of innate immunity.
117-124