Introduction. The negative dynamics of the increase in the prevalence of cardiovascular pathology among industrial workers observed in recent decades within the framework of the tasks of the scientific specialty "occupational health" determines the importance of studying not only professional, but also comorbid pathology in workers, diseases accompanying the professional route, assessing the role of production factors in the development of somatic diseases, including diseases of the circulatory system, in in particular, arterial hypertension.

The study aims to research the possibilities of early diagnosis of vascular disorders in vibration disease in combination with arterial hypertension based on the assessment of endothelial and hemostasiological parameters.

Materials and methods. The study involved 253 patients of the Center for Occupational Pathology of the Novosibirsk State Medical Institution "City Clinical Hospital No. 2", including 144 people working in contact with local vibration for more than 15 years, among them 75 people with vibration disease, 69 people with a combination of vibration disease and hypertension; 72 people with hypertension those who work outside the influence of local vibration and 37 people who work outside of contact with local vibration and have no history of hypertension. The researchers conducted a comparative assessment of the indicators of systemic, vascular-platelet, plasma-coagulation hemostasis, the state of markers of endothelial-cellular hemostasis. Authors determined the aggregation activity of platelets, also studied adhesion molecules, the functional state of the endothelium. We considered the differences statistically significant at p≤0.05.

Results. During the study the researchers found that endothelial dysfunction in vibration disease in combination with arterial hypertension is closely related to the expression of signaling molecules, an increase in endothelin-1 levels in combination with increased production of vascular endothelial growth factor and transforming growth factor. Endothelial markers can be associated with the frequency of unfavorable polymorphic gene variants. In systemic hemostasis, there are: an increase in the level of thrombospondin and thrombomodulin, platelet growth factor in conditions of decreased plasminogen activity, an increase in the concentration of α₂-macroglobulin and fibrin breakdown products. We also identified earlier endothelial-hemostasiological markers of vascular disorders.

Limitations. The study was conducted on the basis of Novosibirsk State Medical University and on the basis of the City Clinical Hospital No. 2. The limitations of the study may be the unidirectionality of the study performed and the small sample of patients participating in the research.

Conclusion. As a result of studying the clinical, functional and molecular characteristics of vibration disease occurring in combination with arterial hypertension, scientists have obtained new knowledge. It is possible to use such knowledge to improve the diagnosis and treatment of patients, scientific justification of health risks, development of prevention and rehabilitation programs.

Ethics. All patients have previously signed an informed consent form to participate in the study. The Ethics Committee of the Novosibirsk State Medical University and the State Medical Institution of the City Clinical Hospital No. 2 has approved the research program, the content of the informed consent, materials of the article.

Contribution:
Shpagina L.A. — concept and design of the study, literature review, writing the text, editing;
Gerasimenko O.N. — writing the text;
Novikova I.I. — concept and design of the study, literature review, editing;
Radoutskaya E.Yu. — literature review, data collection and processing, writing the text;
Gorbunova A.M. — data collection and processing;
Sergeeva Ya.S. — data collection and processing.

Funding. The authors carried out the study with the financial support of the RFBR and the Ministry of Education, Science and Innovation Policy of the Novosibirsk Region within the framework of scientific project No. 77-44-540009.

Conflict of interests. The authors declare no conflict of interests.

Received: 03.03.2022 / Accepted: 01.04.2022 / Published: 25.04.2022

Introduction. The problem of studying the development of stroke in men of working age working in conditions of high occupational risk remains relevant.

The study aims to develop a method for predicting the development of stroke in men working under the influence of local vibration.

Materials and methods. The survey included 136 men aged 30 to 65 years who have worked for 5 or more years in professions: mechanical assembly fitter, installer, grinder, miller, riveter, sharpener, moulder (class of working conditions — 3.1). We divided the study participants into two groups: the first group — 72 men with stroke, the second group — 64 men who had no history of stroke. The subjects of both groups were comparable in professional composition, age and work experience. Using the method of sequential inclusion of the studied stroke risk factors (Forward Stepwise), the researchers have identified those risk factors that have made a significant contribution to the possible development of stroke.

Results. Based on multifactorial analysis, the authors have derived a logistic regression formula that determines the probability of stroke in patients working under the influence of local vibration. The formula included significant factors that significantly contribute to the development of stroke: the patient's diagnosis of "arterial hypertension of the third degre" (β-coefficient=2.7, p=0.001), the absence of taking antihypertensive drugs (β-coefficient=1.3, p=0.01). To determine the probability of stroke, we determine the value of these two parameters and substitute them into the formula for calculating the value of p(X). A value of p(X) exceeding 0.8 indicates a high risk of stroke in men working under the influence of local vibration. The sensitivity of the proposed method was 72.2%, the specificity was 75.0%.

Limitations. The authors excluded from this study: female sex, age less than 30 and more than 65 years, diagnosis of "transient cerebrovascular accident", work experience of less than 5 years, the presence of acute infectious diseases.

Conclusion. The authors have revealed the prognostic value of a combination of individual risk factors for stroke in people working under the influence of local vibration (the presence of a diagnosis of "arterial hypertension of the third degree" in the patient, the absence of taking antihypertensive drugs). The multifactorial model is informative for the individual prediction of stroke in men when exposed to industrial local vibration.

Ethics. The researchers conducted the study in compliance with the "Ethical Principles of Conducting Scientific medical research with human participation" and "Rules of Clinical Practice in the Russian Federation", approved by Order of the Ministry of Health, Russian Federation, No. 266 dated 19.06.2003; approved by the Local Ethics Committee at the Federal State Budgetary Educational Institution of the Ministry of Health, Russian Federation (minutes of the meeting No. 65 dated 27.05.2014).

Contrubution:
Poteryaeva E.L. — research concept and design, editing;
Yashnikova M.V. — research concept and design, data collection and processing, writing the text;
Doronin B.M. — research concept and design;
Maksimov V.N. — static processing of research material;
Smirnova E.L. — data collection and processing.

Funding. The study had no funding.

Conflict of interests. The authors declare no conflict of interests.

Received: 01.04.2022 / Accepted: 18.04.2022 / Published: 25.04.2022

Introduction. Chronic obstructive pulmonary disease (COPD) is one of the most common occupational diseases registered in workers exposed to dust for a long time. This disease significantly worsens the quality of life, requires constant monitoring in the centers of occupational pathology and regular preventive measures. The proportion of COPD in the structure of occupational diseases has not changed significantly for decades, high rates of disability and premature mortality characterized this disease.

The study aims to research the diagnostic parameters of COPD exacerbation under the influence of industrial aerosols and tobacco in the clinic of occupational diseases.

Materials and methods. Researchers examined 153 patients with occupational COPD (toxic gases and inorganic dust). The comparison group consisted of 103 patients with smoking COPD. We established the diagnosis of COPD in accordance with the criteria of GOLD 2011. The duration of the study was 5 years. The authors conducted a complex of clinical and laboratory studies in all patients with an emphasis on the diagnostic parameters of COPD exacerbation and lung function. The critical significance level is p=0.05.

Results. The development of occupational COPD under the influence of industrial aerosols and tobacco affects the frequency and predominant phenotype of exacerbations. Rare but severe exacerbations, mainly with eosinophilic type of inflammation, are present in COPD from the action of toxic gases. They respond well to therapy with systemic GCS. With COPD from the action of dust, hospitalization is not necessary for short-term exacerbations with neutrophilic type of inflammation, since such exacerbations respond to therapy with bronchodilators, and a significant proportion of exacerbations require the use of antibacterial therapy. Also, in COPD from the action of toxic gases, the experience of exposure to aerosols and gases of the production environment is an independent predictor of any exacerbations. But we do not have data on the significance of the length of service and the intensity of dust exposure.

Conclusion. The risks of exacerbations of occupational COPD and the predicted features of their course depend on the etiological production factor, its intensity and duration of exposure. Clinical features determine different tactics of treatment and prevention of health deterioration. With the severity of COPD exacerbation from the action of toxic gases, symptoms of emphysema and hypoxemia are characteristic, with COPD from the action of dust, symptoms of bronchial obstruction, emphysema and hypoxemia are characteristic. Obtained results can use to construct risk meters of exacerbations and the scale of effectiveness of rehabilitation measures, to revise the standards of treatment and prevention of patients with COPD of professional genesis, as well as for the differential diagnosis of occupational obstructive pulmonary disease.

Limitations. The study was conducted on the basis of Novosibirsk State Medical University and on the basis of the City Clinical Hospital No. 2. The limitations of the study may be the unidirectionality of the study performed and the small sample of patients participating in the research.

Ethics. All patients have signed an informed consent form. The study program, the content of the informed consent, and the materials of the article were approved by the local ethics committee of Novosibirsk State Medical University and City Clinical Hospital No. 2. 

Contributions:
Shpagin I.S. — concept and design of the study, literature review, writing text, editing;
Gerasimenko D.A. — concept and design of the study, literature review, writing text, editing;
Novikova I.I. — concept and design of the study, literature review, editing;
Shevkun I.G. — literature review, collection and processing of data, writing text;
Gorbunova A.M. — collection and processing of data, writing text;
Sergeeva Ya.S. — collection and processing of data.

Funding. Russian Foundation for Basic Research and the Ministry of Education, Science and Innovation Policy of the Novosibirsk Region financially supported the study within the framework of scientific project No. 77-44-540009.

Conflict of interests. The authors declare no conflict of interests.

Received: 03.03.2022 / Accepted: 30.03.2022 / Published: 25.04.2022

Introduction. Occupational dust pathology of respiratory organs in Kuzbass remains relevant due to its high prevalence among workers of the coal industry. Entering the body, the components of coal cause the development of pneumoconiotic fibrosis. Innovative ideas about the morphogenesis of fibrosis in recent years have shifted to the molecular level and appeal to the state of cellular receptors, the expression of some genes and the repression of others, a radical change in the cellular phenotype, which is the platform on which complex pathological processes occur.

The study aims to research the mechanisms of fibroplastic changes in the lung tissue of miners from the position of epithelial–mesenchymal transformation.

Materials and methods. The authors carried out histological and immunohistochemical studies of the respiratory system obtained during fifty autopsy operations of a group of Kuzbass miners working in underground. We studied the bronchial mucosa, respiratory lung tissue, arteries and veins of the small and large circulatory circles. The scientists perfomed immunohistochemical study using monoclonal antibodies (marker of proliferation Ki-67; oncogene of proapoptotic activity Bcl-2; endothelial function factors CD-31 and CD-34; marker of epithelial tissue cytokeratin; muscle tissue markers: actin, desmin, vimentin; connective tissue markers: type III collagen; muscle tissue collagenization marker: EMA; intercellular adhesion molecules E and N-cadherins; macrophage antigen (HAM5600)).

Results. Epithelial cells of bronchi of coal industry workers partially lose the ability to express cytokeratins with the replacement of individual cell clusters with cells with non-core expression of maternal epithelial tissue of muscle antigens (vimentin, desmin, actin). When exposed to dust, the epithelial phenotype changes with changes in the quantity, shape and quality of the tissue structures of the lung tissue. Epithelial cells become elongated, fusiform, lose polarity and intercellular connections, acquire mobility and the ability to migrate beyond the tissue histione. Hyperactivation of cellular signaling pathways leads to disorganization and partial disintegration of the cytoskeleton with the appearance of functional mobility of cellular elements. A significant decrease in intercellular adhesive contacts under conditions of prolonged exposure to coal-rock dust leads to suppression of the expression of E-cadherin with partial substitution for N-cadherin contacts. Meanwhile, epithelial cells go through the process of epithelial-mesenchymal transformation, participate in the processes of fibrosis. Activated myofibroblasts are the main source of fibrosis in the lungs, their precursors can be both resident and bone marrow fibroblast-like cells. Dedifferentiated epithelial cells can act as decompensation of the regenerative capacity of lung tissue.

Conclusion. The concepts of epithelial-mesenchymal transformation as a mechanism of the main pathological changes in pneumoconiosis should serve as a foundation for further in-depth study and understanding of the complex pathogenetic aspects of this problem in medicine.

Ethics. The authors conducted all the studies of the dead miners with the help of a secondary examination of blocks and ready-made histological micro-preparations (glasses) of the material of the Bureau of Forensic Medical examination in Novokuznetsk, Osinniki, Prokopyevsk. The researchers carried out studies of pathomorphological material strictly on the basis of Federal Law No. 323-FZ of 21.11.2011 "On the basics of protecting the health of citizens in the Russian Federation", in particular Article 67 "Conducting pathoanatomic autopsies", Federal Law No. 8-FZ of 12.01.1996 "On Burial and Funeral Business" (Article 5, paragraph 1, 2), as well as in accordance with the Order of the Ministry of Health of April 29, 1994 No. 82 "On the procedure for conducting a pathoanatomical autopsy" (appendix to the order of the Ministry of Health and Medical Industry of 29.04.1994 No. 82), Order of the Ministry of Health of Russia of 24.03.2016 No. 179n "On the rules for conducting pathoanatomical studies".

Contribution:
Bondarev O.I. — research concept and design, data collection and processing, writing the text, editing;
Bugaeva M.S. — data collection and processing, writing the text, editing;
Kazitskaya A.S. — data collection and processing.

Funding. The study had no funding.

Conflict of interests. The authors declare no conflict of interests.

Received: 17.02.2022 / Accepted: 05.03.2022 / Published: 25.04.2022

Introduction. Revision of the "Guidelines for the hygienic assessment of factors of the working environment and the labor process. Criteria and classification of working conditions" R 2.2.2006-05 determined the relevance of improving hygienic criteria and classification of working conditions, including noise, based on a risk-based approach.

The study aims to substantiate risk–oriented hygienic criteria and classification of working conditions by noise, taking into account the group attributive (excessive) risk of hearing loss.

Materials and methods. The researchers carried out an expert-analytical study and calculations of the attributive risk of hearing loss under the influence of noise. The authors used a technology (ARHL) according to the model of the third edition of the ISO 1999 standard. We performed the calculation of ARHL using several variants of the average values of hearing thresholds at various combinations of audiometric frequencies.

Results. Scientists have substantiated a risk-oriented criteria and classification of working conditions depending on noise levels, taking into account the equal energy rule (q=3) and the data of the group attributive risk of hearing loss.

Conclusion. We substantiated a risk-oriented hygienic criteria and classification of working conditions by noise, harmonizing the hygienic assessment of the noise risk factor with international practice.

Ethics. In preparing the article, the authors guided by the Ethical principles of medical research set out in the Helsinki Declaration of the World Medical Association of the last revision.

Limitation of studies. There are the features of the model for assessing hearing loss due to noise exposure according to GOST R ISO 1999:2013.

Contribution:
Prokopenko L.V. — research concept and design, writing, editing;
Kuryerov N.N. — research concept and design, data calculation and analysis, text writing, editing;
Lagutina A.V. — data collection and processing, editing;
Pochtariova E.S. — material processing.

Funding. The study had no funding.

Conflict of interests. The authors declare no conflict of interests.

Received 31.03.2022 / Accepted: 05.04.2022 / Published: 25.04.2022

Introduction. The researchers carried out the analysis of work and rest modes (WRM) according to the survey data of 667 pilots and the results of investigations of 83 aviation accidents (AA) that occurred in the Russian Federation with heavy aircraft (HA) weighing more than 5,700 kg for the period 2010–2021. We also considered the data of official statistics for the period from 2005 to September 2021. The obtained results indicate the facts of non-compliance with the work and rest modes (WRM), which may be one of the causes of aviation accidents (AA). In this regard, it is relevant to optimize the work and rest modes in order to improve flight safety in civil aviation and organize their stricter control.

The study aims to assess the impact of the actual compliance with the WRM of the crew members of the Civil Aviation Aircraft (CAA) on the occurrence of aviation accidents and to develop proposals for their optimization and control.

Materials and methods. The authors studied a compliance of work and rest modes based on the results of 667 online questionnaires developed on the basis of recommendations of the International Civil Aviation Organization (ICAO) on the introduction of a risk management system in airlines related to pilot fatigue, and data from 83 aviation accidents (AA) for the period from 2010 to 2020, presented in the reports of the Interstate Aviation Committee (IAC) on the results of the investigation the causes of their occurrence. When assessing the relevance of the topic, we considered the data of official statistics.

Results. The data of the study indicate that in 18% of cases, one of the main causes of AA was non-compliance with WRM. Among the causes of aviation accidents, the following are important: exceeding the norms of flight time for a month (detected in 10% of cases) and for a year (up to 30%); insufficient preflight rest (46.5% of aircraft commanders and 7.4% of co-pilots); lack of full-fledged vacation for a year (32% of cases). In many cases the Researchers revealed several facts of different violations of work and res modes simultaneously. Data of online questionnaire survey confirm the high prevalence of severe fatigue among pilots: 44% rarely have time to rest between flights, 86% go on a night flight shift without having a full day's sleep. We determined the interrelations between the frequency of fatigue of pilots associated with various types of violations of WRM and the risk of air crashes: the prevalence of fatigue and the frequency of disasters increased with a decrease in the duration of pre-flight rest, an increase in vacation arrears and other factors from 1.2 to 2.1 times.

Conclusion. The results of the study confirm the high significance of WRM disorders in the occurrence of aviation accidents (AA). The researchers compiled a comprehensive program to reduce accidents in air transport associated with violations of WRM and the development of fatigue among crew members. We have provided proposals to amend the current Regulations on WRM.

Ethics. Authors carried out the study in accordance with the International Code of Medical Ethics (1949) and the provisions of the Helsinki Declaration adopted by the World Medical Association (1964). When conducting an online questionnaire survey, before the start of the study, we have introduced all participants with the methodology of its conduct, associated risks and signed an informed voluntary consent.

Contribution:
Zibarev E.V. — the concept and design of the study, writing the text;
Kravchenko O.K. — data collection and processing;
Klimov A.A. — data collection and processing;
Ivashov S.N. — data collection and processing.

Funding. The study had no funding.

Conflict of interests. The authors declare no conflict of interests.

Received: 31.03.2022 / Accepted: 04.04.2022 / Published: 25.04.2022

Underground mining of chrome ores is characterized by constant exposure to chemical factors on production workers, which leads to the occurrence of pathological changes on the part of critical organs and systems.

The aim of the study is to assess changes in the content of biochemical parameters and protein fractions in the blood serum of workers employed at an enterprise for underground mining of chrome ores.

The content of chromium in the air of the working area and the blood of workers was assessed, a number of biochemical parameters were investigated by unified biochemical methods (IgE specific to chromium, ALAT, γ-HT, creatinine, β₂-microglobulin in blood serum, β₂-microglobulin in urine, calculation of the glomerular filtration rate) and protein fractions in blood serum using electrophoresis of proteins in agarose gel, modeling of cause-and-effect relationships was carried out.

The workers of the mine mining of chromium ores showed a significant increase in the level of chromium in the blood up to 1.3 times, an increase in the level of IgE specific to chromium up to 1.6 times, the activity of ALAT and γ-HT in the blood serum up to 1.3 times, the level of β₂-microglobulins in blood serum and urine up to 1.6 times, serum creatinine level, decrease in glomerular filtration rate, increase in serum β-globulin and γ-globulin level relative to similar indicators among employees of the enterprise employed outside the influence of a chemical factor.

The constant presence of chromium compounds in the air of the working area leads to an increased concentration of chromium in the blood of workers. An increase in the activity of ALAT and γ-HT in the blood serum, the level of β₂-microglobulins in the blood serum and urine, the level of creatinine and IgE specific to chromium in the blood serum, and a decrease in the glomerular filtration rate were found. Changes in protein fractions in blood serum (increase in the level of β-globulins and γ-globulins) were revealed in workers at the mine mining of chromium ores.

Ethics. When conducting the study, the authors were guided by the ethical principles of medical research with human participation as a subject, set out in the Declaration of Helsinki by the World Medical Association of the last revision and received informed voluntary consent from each employee to participate in the survey.

Contribution:
Zemlyanova M.A. — research concept and design, editing;
Peskova E.V. — research concept and design, text writing;
Koldibekova Ju.V. — research concept and design, text writing;
Pustovalova O.V. — data collection and processing.

Funding. The study had no funding.

Conflict of interests. The author declares no conflict of interests.

Received: 09.06.2021 / Accepted: 02.02.2022 / Published: 25.04.2022