Coping Strategies During the COVID-19 Pandemic and Self-Determination: A Review of Russian Studies.

Background: The COVID-19 pandemic is a multifaceted stressor. Its impact suggests long-term psychological effects. Self-determination promotes flexibility of goals and actions and helps to overcome the difficulties caused by stress. Objective: To analyze coping strategies during the COVID-19 pandemic presented in Russian scientific studies (RQ1), and their relationship with self-determination (RQ2). Design: Relevant studies (2020-2022) were selected from the Russian citation index (RSCI) database. Strict selection criteria were used. Twenty-four articles were selected for the final review. For dynamic analysis, four stages of the pandemic were identified. Results: Prevailing coping strategies have changed over time. At the beginning of the pandemic, respondents used familiar coping mechanisms. Six months later, active coping strategies were more often used, but deprivation and avoidance strategies increased. A year later, there was an increase in denial and avoidance strategies. Using non-constructive coping strategies may indicate that, due to the long course of the pandemic, meeting basic psychological needs became increasingly frustrated, leading to helplessness, alienation, and lack of control. Later dynamics reflect the growth of effective coping strategies and confirm that when basic needs are blocked for a long time, people seek alternative ways to satisfy them. Conclusion: The dynamics of coping strategies during the pandemic reflected their close relationship with basic psychological needs, as described in the theory of self-determination. The results confirmed the importance of self-determination as a dispositional variable in predicting coping mechanisms.

Anti-tumor Effect of High Doses of Carbon Ions and X-Rays during Irradiation of Ehrlich Ascites Carcinoma Cells Ex Vivo.

The effect of carbon ions (12C) with the energy of 400 MeV/nucleon on the dynamics of induction and growth rate of solid tumors in mice under irradiation of Ehrlich ascites carcinoma cells (EAC) ex vivo at doses of 5-30 Gy relative to the action of equally effective doses of X-ray radiation was studied. The dynamics of tumor induction under the action of 12C and X-rays had a similar character and depended on the dose during 3 months of observation. The value of the latent period, both when irradiating cells with 12C and X-ray, increased with increasing dose, and the interval for tumor induction decreased. The rate of tumor growth after ex vivo irradiation of EAC cells was independent of either dose or type of radiation. The dose at which EAC tumors are not induced within 90 days was 30 Gy for carbon ions and 60 Gy for X-rays. The value of the relative biological effectiveness of carbon ions, calculated from an equally effective dose of 50% probability of tumors, was 2.59.

Diastereoselective intramolecular cyclization/Povarov reaction cascade for the one-pot synthesis of polycyclic quinolines.

The method for the synthesis of complex alkaloid-like aza-heterocycles has been developed through the Povarov reaction of in situ generated 2-oxoimidazolium cations. The reaction lead to the formation of 2 C-N, 2 C-C bonds and three stereocentres, and features excellent regio- and diastereoselectivity. Based on the controlled experiments and quantum chemistry data, the mechanism of the reaction cyclization was proposed and diastereoselectivity origins were rationalized. Additionally, a straightforward synthesis of hardly accessible 4,4'-bi(imidazol-2-one) derivatives has been achieved using the same methodology.

Combined Effect of Low-Intensity Helium-Neon Laser and X-Ray Radiation on in Vivo Cellular Response of the Whole Blood and Lymphoid Organs in Mice.

We studied the effect of exposure to helium-neon laser (dose range 0.16-50 mJ/cm2) on activation of natural protection reserve in mice using the adaptive response test. DNA comets method revealed a protective response manifested in DNA damage level in whole blood leukocytes of mice and in lymphoid organs by the thymus and spleen weight index; preexposure to laser did not induce the adaptive response. ROS level in the whole blood was assessed by the level of zymosan-induced luminol chemiluminescence. In mice subjected to adaptive laser irradiation in doses of 0.16-5 mJ/cm2 followed by X-ray irradiation in a dose of 1.5 Gy, the activation index calculated as the ratio of induced to spontaneous area of luminescence was by 1.4 times lower than that in non-irradiated animals, which attested to reduced ROSgeneration reserve capacity of neutrophils.

[Induction of DNA damage in blood leucocytes and of cytogenetic injuries in bone marrow polychromatic erythrocytes in mice exposed to low-LET and high-LET radiation and in their progeny].

The present work was aimed at studying the molecular and cellular levels of the response of the hematopoietic system in mice and their progeny to the action of low-LET and high-LET radiation at different times after exposure. The damage to the genome at the molecular level was assessed by the comet assay in peripheral blood leucocytes, whereas at the cellular level it was estimated by means of the micronuclear test in the marrow cells, after exposure of mice to X-radiation of 1, 3 and 5 Gy and to a high-LET low-intensity radiation at thedoses of 0.14 and 0.35 Gy, as well as to a combined effect of these types of radiation. When accessing the level of the DNA damage to individual cells by the comet assay, we also used, apart from a commonly accepted parameter %TDNA, additional characteristics: the proportions of leucocytes with an intact and highly fragmented DNA. Using these parameters, we detected the changes characterizing the dynamics of the leukocyte population in mouse blood at different times after the action of X-ray and high-LET radiation. It was found that: (1) the DNA damage increases with the dose of high-LET radiation; (2) the level of damage in the progeny of the animals exposed to high-LET radiation does not differ from that in unirradiated animals both at the molecular and cytogenetic levels; and (3) a decrease in the radiosensitivity of the progeny of the mice exposed to high-LET radiation at a dose of 0.35 Gy makes itself evident only at the molecular level, which may point to the possible transgeneration transmission of genomic lesions.

A method of low-temperature storing of agarose slides with lysed cells.

A method has been developed for a long-term low-temperature storage (-10 to -15°C) of the agarose slides with nucleoids (lysed eukaryotic cells). After lysis of agarose-immobilized cells, the slides were incubated for 30 min in phosphate buffer with 50% glycerol and 100 mM EDTA, thereupon they were stored in a freezer at -10 to -15°C. After long-term storage, the slides were re-incubated for 30 min in lysing solution. The measurements of the baseline and in vitro induced DNA damage in nucleoids of the human and mouse leukocytes, which had been stored in agarose slides at low temperature, showed that DNA damage level determined after a 40-day storage did not significantly differ from that of the fresh slides. The advanced storage method is simple and reliable; it opens the way to avoid cryopreservation of the biological samples and to process little by little a great number of the identically prepared slides.

[Experimental detection of integration of mTDNA in the nuclear genome induced by ionizing radiation].

Transfer of mtDNA in the nuclear genome is usually regarded as a continued and dynamic process of forming numt-pseudogenes or numt-insertions. They can be regarded not only as a neutral polymorphism, but may be involved in oncogenesis, aging and genetic diseases. Experimental identification of numt-insertions arising de novo is limited due to the presence of numerous homology mtDNA constitutively existing in the nuclear genomes of eukaryotes. It is known that the chick nuclear DNA (nDNA) constitutively contains 12 numt-pseudogenes. We attempted to experimentally detect the formation of numt-insertions de novo in the nDNA of chick embryos (Gallus gallus) from the eggs exposed to X-rays. Free mtDNAs were removed from preparations of nDNA of liver embryos through double gel electrophoresis. Numt-inserts in nDNA of control and survival embryos (from irradiated eggs) were revealed by PCR using 11 pairs of primers flanking the region of mtDNA of about 300-400 bp. PCR analysis with nDNA of control group showed no presence of homology mtDNA amplified with selected primers. PCR assays of nDNA of eight embryos from irradiated eggs showed that nDNA of two embryos contained new sites of mtDNA. PCR amplification of 3 loci of mtDNA is stably detected in nDNA from one embryo and 4 loci of mtDNA in nDNA from another embryo. Sequencing of PCR amplicons synthesized on templates of these nDNA showed that their sequences are identical to mtDNA and accurately cover the sites of several genes and the site of mtDNA D-loop. Thus, the experimental results indicate that ionizing radiation can induce integration of mtDNA fragments in the nuclear genome, apparently, through the mechanism of nonhomologous end-joining repair of double-strand breaks of nDNA.

Effects of neurotensin dipeptide analog dilept on dopamine metabolism and synthesis in the nucleus accumbens of Wistar rats.

We studied the effects of neurotensin dipeptide analog Dilept (N-caproyl-L-prolyl-L-tyrosine methyl ester) on dopamine metabolism and synthesis in the nucleus accumbens of Wistar rats. Dilept increased the levels of dopamine and its metabolites (homovanillic acid and dioxyphenylalanine) and stimulated dopamine turnover in this structure. Dilept accelerated dopamine synthesis under conditions of pulsed activity blockade in dopaminergic neuron by injection of γ-butyrolactone combined with inhibition of aromatic acid decarboxylase with 3-hydroxybenzylhydrazine. The spectrum of pharmacological activities of Dilept towards the dopaminergic system of the nucleus accumbens was similar to that of atypical neuroleptics and neurotensin (endogenous antipsychotic).

[Role of various risk factors in the development and diagnosis of recurrent pain in adolescents--students of cadet corps].

Randomized single-blind case--control study is performed. In total, the cadet corp students with recurrent functional abdominal pain and headaches are examined. The paper shows the role of various risk factors in the occurrence of these states. Diagnostic validity is evaluated. Multifactorial genesis of the studied pathology is proved. The essential role in the formation of the psychological characteristics of personality, neurotic states and autonomic dysfunction is shown. Several constitutional characteristics of the organism were not diagnostically significant.

Changes in the level of spontaneous DNA damage in whole blood leukocytes during storage.

We evaluated structural damage to DNA (%TDNA) in blood leukocytes from healthy donors of different age at different periods (0-6 days) of blood storage at 4-8°C. It was found that the basal level of DNA damage increased and intracellular antioxidant level decreased during storage. Mean %TDNA was 6.8±3.3% in the fresh blood and 19.2±8.1% after 5-day storage. The experiments with exposure to reactive oxygen species induced by irradiation suggest that depletion of low-molecular-weight endogenous antioxidants occurs as soon as after 5-h storage. Our results suggest that storage time should be taken into account when assessing the basal and induced levels of leukocyte DNA damage by the comet assay.

[Evoked potentials and brainstem reflex activity in patients of young and middle age with chronic headache].

Neurophysiological peculiarities of functional state of afferent systems, including brain evoked potentials of different modalities and brainstem reflex activity, in patients of young and middle age with chronic headaches have been studied. In young patients, there was the increased reflex activity of visual and trigeminal systems, somatosensory cortex and brainstem structures that indicated the main role of the generator of pathologically increased excitation (GPIE) of different levels in the pathogenesis of chronic pain. In patients of middle age, we observed the predominant role of conduction delay on the supraspinal level. The revealed age-related neurophysiological peculiarities determine the pathogenetic therapy of chronic headaches.

[Neurophysiological assessment of afferent-efferent interaction in the trigeminal-cervical system in patients with secondary headaches].

We carried out the neurophysiological assessment of functional state of the trigeminal-cervical system and studied peculiarities of afferent-efferent interaction in patients with the most frequent variants of secondary headaches: chronic posttraumatic headaches, cervicogenic headaches, vascular headaches and painful dysfunction of temporomandibular articulation. According to the results of neurophysiological studies (somatosensory, trigeminal evoked potentials, blink reflex and stimulation EMG of masticatory muscles), the functional activity of the trigeminal system in patients with secondary headaches changes less significantly compared to patients with primary headaches. In most secondary headaches, the reflex activity of the trigeminal system and the EMG activity of masticatory muscles are determined by the functional state of spinal and brainstem structures.

[The comet assay application in radiobiological investigations].

The analysis of the literature data on application of the gel electrophoresis of individual cells ("comet assay") in radiobiological investigations was carried out. The descriptions of various variants of the method are presented; its alkaline version is in more detail considered. The works concerning to induction and DNA damage repair of single stranded and double stranded DNA breaks, DNA alkali labile sites, crosslinks, DNA bases damage, cellular radiosensitivity and revealing of apoptotic cells were analyzed. The application of the method at biomonitoring of DNA damage level in cells of the person and the animals exposed to genotoxic agents, including ionizing radiation is described. The analysis of the literary data testifies to perceptivity of development and further uses of this method in radiobiological researches.

[Vestibular-spinal reflex in patients with vestibular-ataxic syndrome of different genesis].

The article presents the results of investigation of vestibular-spinal reflex (vestibular myogenic evoked potentials) in healthy subjects and patients with vestibular-ataxic syndrome. The inhibition of vestibular-spinal reflex with the P13 latency increase was shown to be the most characteristic of demyelinating and traumatic brain diseases. The P13 latency increase was not pathognomic for any disease of the nervous system but was indicative of conduction delay in vestibular-spinal tracts.

[Evoked potentials in patients with secondary headaches].

Characteristics of brain evoked activity were studied in patients with most frequent variants of secondary headaches: chronic posttraumatic headaches, cervicogenic headaches and vascular headaches in patients with arterial hypertension and chronic brain ischemia. The multimodal registration of evoked potentials (EP) (short-latency brainstem auditory, visual EPs to flash stimulation and cognitive EPs - P300) revealed signs of brainstem dysfunction, decrease of visual analyzer and diminished cognitive functions in most patients with secondary headaches. Based on results obtained, we can recommend a complex therapy of chronic secondary headaches with neuroprotectors and nootropics.

[Neurochemical study of effects of the new anxiolytic drugs afobazol and ladasten on the synthesis and metabolism of monoamines and their metabolites in the brain structures of Wistar rat on the model of monoamine synthesis blockade induced by aromatic amino acid decarboxylase inhibitor NSD-1015].

Results of a neurochemical study of the effects of the new anxiolytic drugs afobazole and ladasten on the synthesis and metabolism of monoamines and their metabolites determined by HPLC on the model of monoamine synthesis blockade induced by NSD-1015 (aromatic L-amino acid decarboxylase) in the brain structures of Wistar rats are reported. A decrease in the levels of DOPAC in hypothalamus and HVA in striatum after afobazole injection may be evidence of an inhibitory action of this drug on the activity of monoamine oxidase (MAO-A), which is the main enzyme involved in dopamine biodegradation. Afobazole was also found to increase the content of serotonin (5-HT) as well as its precursor (5-OTP) and its main metabolite (5-HIAA) in hypothalamus by up to 50, 60 and 50%, respectively, which confirms a hypothesis that this anxiolytic drug can modulate the activity of tryptophan hydroxylase (5-OTP synthesis enzyme). In contrast to afobazole, ladasten demonstrated the ability to increase the level of L-DOPA (a dopamine precursor) in virtually all functional structures of the brain (except for hippocamp), which may support the hypothesis suggestion concerning a predominant action of this drug on the activity of tyrosine hydroxylase. Ladasten exhibited selectivity with respect to the dopaminergic system and affected only parameters of the dopamine metabolism, in particular, by increasing the HVA content in nucleus accumbens and decreasing it in the hypothalamus. The drug also affected the dopamine turnover parameters, producing an increase in both HVA/dopamine ratio in nucleus accumbens and DOPAC/dopamine ratio in hippocamp.

[Information-wave technologies: rationale and guidelines for their use in pediatrics].

The mechanisms of action of information-wave technologies on human beings are analyzed in detail and their use in pediatrics is substantiated. The approach using a now-frequency pulse electromagnetic field as an information factor is optimal due to the synchronization of an oscillatory process of a low-frequency pulse electromagnetic field and the rhythm of functioning of different systems of the body, which causes the bioresonance actions the function of an organ or a system.

Spontaneous DNA damage in peripheral blood leukocytes from donors of different age.

Spontaneous DNA damage in peripheral blood cells was studied in healthy donors of different age (23-70 years). Alkaline comet assay was used to evaluate total DNA damage in individual cells. The individual variability in venous blood samples was higher than in capillary blood samples. The advantage of analysis of DNA damage in nucleated cells from the whole blood is more preferable compared to experiments with isolated lymphocytes because all cell populations in the sample are analyzed. Study of blood cells from healthy donors showed that the mean percent of DNA in the comet tail tended to decrease with age. However, correlation analysis revealed no relationship was found between donor age and degree of spontaneous DNA damage.

DNA damage in human mononuclear cells induced by bacterial endotoxin.

Damage to nuclear DNA in human peripheral blood mononuclear cells was studied after in vitro treatment with bacterial endotoxin by alkaline comet assay. It was found that LPS induced DNA damage as soon as over the first 30 min of incubation, while by the 4th hour of incubation DNA damage was found in more than 95% cells. Exogenous superoxide dismutase completely protected DNA, which suggests that superoxide radical is the primary extracellular damaging agent. Polyphenol antioxidant (water-soluble lignin) and specific NADPH oxidase inhibitor (diphenyleneiodonium chloride) also produced a protective effect. Our results show that LPS-activated mononuclear cells can be used ex vivo as a convenient and adequate experimental system for evaluation of the efficiency of various substances in protection of lymphocyte DNA from the damaging effect of reactive oxygen species of LPS-stimulated monocytes.

Development of genetic instability in mice in response to chronic irradiation simulating high-altitude flight conditions.

The purpose of this work was to study the chronic influence of the high-energy radiation field formed in the atmosphere at an altitude of 10 to 30 km on the level of DNA damage in leukocytes of peripheral blood in mice. The external radiation field (behind the concrete shield) of the U-70 accelerator (Serpukhov, Russia) was used for these studies. This radiation field simulates the components and spectral composition of the high-energy radiation field formed in the atmosphere at an altitude of 10 to 30 km. Two groups of SHK line mice were chronically irradiated with a total dose equivalent to 21.5 and 31.5 cGy. The state of the genome of nucleated blood cells was assessed by the Comet assay (alkaline version) 72 h after completion of chronic irradiation. The level of genome damage in individual peripheral blood leukocytes of irradiated animals was compared with the basal level of DNA lesions in peripheral blood leukocytes of unirradiated control mice. The damage was expressed in %TDNA (the amount of DNA found in the "comet tail" in percent of total DNA in the "comet"). It was found that in mice exposed to the radiation field of the accelerator, the mean value of DNA damage was: %TDNA = 3.88 +/- 0.35% for a dose of 21.5 cGy and % TDNA = 6.00 +/- 0.82% for a dose of 31.5 cGy. In mice irradiated at an X-ray therapeutic device with a dose of 150 cGy 24 h before the examination, %TDNA was 2.27 +/- 0.34% and this did not differ from %TDNA in unirradiated mice, 2.68 +/- 0.56%. We suggest that the increased level of DNA damage observed in mice irradiated with 31.5 cGy from the mixed radiation field at the Serpukhov accelerator points to the development of genetic instability in their leukocytes as a result of chronic exposure of animals to this particular radiation field.