Introduction. The transfer function of the outer ear is an important characteristic of the hearing organ, determined by the acoustic properties of the auricle and the external auditory canal, their shape and size. The acoustic impedance of the eardrum is also likely to matter.

The frequency characteristics of the transmission function of the outer ear must be taken into account when choosing individual noise protection devices and when prosthetics of the hearing organs. Measurements of the sound pressure distribution along the auditory canal carried out by various researchers with a probe microphone have shown that for frequencies above 3 kHz, it can vary significantly. At the same time, it was noted that the relative measurements of the actual acoustic characteristics of hearing aids and individual noise protection devices, when the end of the microphone probe does not change position, are quite accurate (Sullivan, 1988; Traynor, Ackley, Wiersbowsky, 1989; Johnson, Nelson 1991; Hellstrom, Axelsson, 1993; Searchfield, Purdy, 1997).

The study aims to evaluate the reproducibility of the F-MIRE method and the accuracy of the measurement results of the transfer function of the outer ear when fixing the probe microphone with a wire bracket from a set of microphone devices; to determine possible changes in the acoustic characteristics of the outer ear under the influence of noise of various levels, their relationship with the size of the auricle and the external auditory canal, the state of auditory function.

Materials and methods. Using the F-MIRE method (microphone in a real ear) in the third-octave frequency bands and in frequency corrections A and C, specialists repeatedly measured the transfer function of the outer ear (TFOE) when exposed to broadband noise of various levels in 17 subjects (16 men and 1 woman) aged 25 to 80 years in a sound chamber. The  researchers determined the geometric dimensions of the auricle and the auditory canal. The otolaryngologist examined all the subjects with an audiological examination. Each subject gave informed consent to participate in the study.

Results. Experts have established according to the data of the conducted research:

1. The most informative indicators of the transfer function of the outer ear — TFOE is its value at the frequency of the first resonance, in the third-octave frequency bands 500–4000 Hz and in the frequency correction A, while the most accurate are the measurement results in the third-octave frequency bands close to the resonant one.
2. The range of TFOE spectral measurement results increases in the third-octave bands of 4.0 kHz and above. In this frequency range, both interference of the direct and reflected sound waves from the eardrum and inaccuracy of positioning of the probe microphone can affect.
3. The transfer function of the outer ear is individual, the TFOE of the left and right ears are different in the subjects.
4. The main resonance in the majority of subjects of the left ear of 14–22 dB and the right ear of 11–18 dB is in the third octave band of 2.5 kHz.
5. In most subjects, the TFOE of the main resonance of the left ear exceeds the value of the right ear by 0.5–6 dB.
6. There was no significant dependence of TFOE changes on the level of impacting noise (changes in the acoustic impedance of the eardrum).
7. A reliable relationship between the TFOE value at the main resonance and the size of the auricle and the external auditory canal was determined only in a part of the subjects for the right ear.
8. The reproducibility of the F-MIRE method for measuring spectral values of TFOE can be estimated as high if the subjects were motionless during the measurements.

Conclusion. The present study is an attempt to evaluate the capabilities of the MIRE (F-MIRE) method, its reproducibility and accuracy. The researchers have shown the potential of the method for analyzing the effects of noise on hearing and understanding the influence of various factors on the accuracy of sound pressure measurements in the external auditory canal.

Funding. The study had no funding.

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

Received: 27.06.2024 / Accepted: 03.07.2024 / Published: 31.07.2024

Introduction. The improvement of methodological approaches to identify the indicator indicators of the fine cellular-molecular profile of immune regulation and genetic polymorphism will optimize the implementation of measures for the early diagnosis and prevention of professionally caused diseases.

The aim of the study to research the features of cytokine immune regulation in employees of a potash ore processing enterprise associated with polymorphism of the MMP9 836A>G matrix metalloproteinase gene (rs17576).

Materials and methods. The authors have examined 64 employees of a potash ore processing enterprise working under the influence of harmful production factors, including dust factor. The comparison group consisted of 56 employees from the administrative staff. The researchers determined immunoglobulins in the radial immunodiffusion reaction. They studied the cytokine content by solid-phase enzyme immunoassay. Genotyping was performed by polymerase chain reaction in real time.

Results. Immunological examination of the main production workers revealed activation of the humoral link in IgG content in 50% of the examined and expression of mediators of proinflammatory cytokine regulation — VEGF by 1.28 times, IL‑1beta by 1.29 times, IL-6 by 1.58 times relative to the comparison group, associated with polymorphic changes in the matrix metallopriteinase-9 gene. The carriage of the variant G*836A>G allele of the MMP9 gene was significantly associated with increased VEGF expression (1.4 times) relative to the workers of the comparison group (mainly carriers of the AA genotype of the MMP9 gene), which allows us to consider the G allele as a marker of sensitivity of the examined group of workers of the main production of the potash ore enrichment enterprise (OR=1.73; 95% CI=1.03–2.93), which forms the risk of lung fibrosis under the influence of dust factor.

Limitations. The present study requires further study of the issue and verification of the data obtained due to the limited size of the sample examined.

Conclusion. The authors established a reliable association of VEGF expression with the variant allele G*836A>G of the MMR9 gene (OR=1.73; 95% CI=1.03–2.93), which indicates a pathogenetic relationship of the immune (cytokine) «storm» with remodeling of extracellular matrix structures and the formation of further fibrous changes in mucous membranes, as one of the proposed mechanisms of the development of production-related lung pathology associated with the dust factor in employees of a potash ore processing enterprise. Timely diagnostic methodological approaches to the identification of cytokine and genetic profile indicators allow us to substantiate the hypothesis of the formation of lung production pathology and recommend personalized programs for early diagnosis and prevention of health disorders of employees of the main production of the potash ore processing enterprise.

Ethics. All surveyed employees gave informed consent to participate in the study. The study was carried out in accordance with the Helsinki Declaration of the World Medical Association (revised 2013). The protocol of the study was approved by the Biomedical Ethics Committee of the local Ethical Committee of the Federal Scientific Center for Medical and Preventive Health Risk Management Technologies No. 5 dated 05/15/2023.

Contribution:
Starkova K.G. — the concept and design of the study, collection and processing of material, writing the text;
Dolgikh O.V. — the concept and design of the study, editing, responsibility for the integrity of all parts of the article;
Alekseev V.B. — the concept and design of the study, editing, responsibility for the integrity of all parts of the article;
Legostaeva T.A. — collection and processing of material, writing the text;
Kazakova O.A. — collection and processing of material.

Funding. The study had no funding.

Conflict of interests. The authors declare the absence of obvious and potential conflicts of interests in connection with the publication of this article.

Received: 21.05.2024 / Accepted: 10.06.2024 / Published: 31.07.2024

Introduction. Modern working conditions create high tension in the regulatory mechanisms of the circulatory system with a decrease in the functional capabilities of the workers’ body, which leads to the development of pre-nosological conditions. The determination of the Myznikov index is aimed at identifying individuals with different levels of adaptation to factors of the labor process and the risk of developing premorbid conditions.

The study aims to evaluate the information content of the Myznikov index in a personalized approach to determining the functional state of the cardiovascular system of workers in neuro-emotional labor.

Materials and methods. Specialists have conducted a physiological characterization of the functional state of the body of locomotive crew workers according to the data of pre-shift medical control. Using a mathematical method based on heart rate and blood pressure, the authors have calculated the value of the Myznikov index and its ideal value. The obtained compliance coefficient made it possible to assess the functional state from acceptable to overvoltage. The Kerdo vegetative index was calculated. The researchers conducted statistical processing of the data obtained using IBM SPSS Statistics 26 software.

Results. Research has established statistically significant differences in hemodynamic parameters among locomotive drivers and assistant drivers in four age groups (p<0.02). Individual analysis established a more homogeneous histogram of Myznikov index indicators in workers aged 55–59 years compared to the age group 30–34 years, which is confirmed by the data of the Kerdo vegetative index. The values of the Myznikov index correspond to the state of functional tension in 11.0–16.7% of cases.

Conclusion. The group of machinists of JSC Russian Railways are at increased risk of overexertion and the development of work-related diseases of the cardiovascular system. A personalized analysis of hemodynamic parameters during a pre-trip medical examination revealed values of the Myznikov index corresponding to an unfavorable functional state, which may reduce the level of traffic safety. Assessing the stages of the adaptation process will allow a differentiated approach to the scientific substantiation of health-improving measures.

Limitation. There are limitations due to the peculiarities of collecting (obtaining) physiological data during pre-trip medical examinations.

Ethics. The study was approved by the local Ethics Committee of the Izmerov Research Institute of Occupational Health (protocol No. 4 of 04.14.2021).

Contribution:
Glukhov D.V. — concept and design of the study;
Yushkova O.I. — text writing, editing;
Kapustina A.V. — collecting and processing material, text writing;
Forverts A.Yu. — collection and processing of material, editing;
Kostenko N.A. — collection, processing of material.

Funding. The study had no funding.

Conflict of interests. The authors declare no conflict of interests

Received: 05.02.2024 / Accepted: 06.25.2024 / Published: 31.07.2024

Introduction. There is still no understanding of whether the clinical characteristics of COVID-19 (including the recovery period) in health care professionals may differ from the general population. It is logical to assume that a higher viral load of SARS-CoV-2 in health care professionals may lead to worse clinical outcomes, especially in the presence of comorbid cardiovascular pathology.

The study aims to scientifically substantiate and develop criteria for assessing the long-term cardinal consequences of COVID-19 in health care workers who are at high biological risk in the performance of their work duties, as well as to evaluate the effectiveness of their treatment.

Materials and methods. Of the 350 patients included in the «Prospective Registry of persons with pneumonia associated with COVID-19, 45 of the 67 medical workers suffered from arterial hypertension (AH). The control group consisted of 90 patients with arterial hypertension, comparable to group 1 in age, gender, body mass index, work experience and severity of hypertension. The researchers assessed clinical, laboratory and instrumental parameters in the groups during the hospital period for pneumonia caused by COVID-19 and 3 months after discharge. Symptoms of anxiety, depression (GAD7, PHQ 9 scales), stress (perceived stress scale-10) and quality of life (according to the SF-36 questionnaire) were assessed.

Results. In the hospital period, with comparable severity of pneumonia in the groups, duration of hospitalization, stay in intensive care units and intensive care units, genetically engineered biological drugs were more often used in the group of medical workers. 3 months after discharge, the body mass index in both groups corresponded to grade 1 obesity. There were no intergroup differences in the frequency of prescribing groups of drugs. The average values of total cholesterol, low-density lipid cholesterol, very low-density lipid cholesterol, glycated hemoglobin and highly sensitive C-reactive protein were higher than normal in both groups. The left ventricular ejection fraction (LVEF) in both groups corresponded to the norm, however, the group of medical workers was distinguished by higher indicators of systolic and diastolic LV function. A decrease in global longitudinal deformation of the left ventricle was registered in 20.0% of medical workers and in 23.9% of patients in the control group (p=0.798). Symptoms of anxiety on the GAD7 scale were significantly more common in the group of medical workers.

Limitation. This study was limited by the duration of follow-up (3 months after COVID-19 pneumonia) and the sample size.

Conclusion. Thus, the main criteria for assessing the cardinal consequences of COVID-19 (post-COVID-19 syndrome) health care workers include: high prevalence of arterial hypertension (67.2% of the total number of health care workers); elevated levels of total cholesterol, low-density lipid cholesterol, very low-density lipid cholesterol; presence of subclinical disorders of LV function (high frequency of reduction of LV global longitudinal strain — up to 20.0% of the total number of observations); excess glycated hemoglobin levels; increased levels of highly sensitive C-reactive protein and high average values of the ratio of neutrophils to lymphocytes (NLR) associated with an increase in the number of lymphocytes and a decrease in the number of neutrophils in the long term after COVID-19 pneumonia.

In the group of health care workers, there was significantly more frequent detection of anxiety symptoms on the GAD7 scale, which, in our opinion, contributes to an increase in the severity of the course of the cardiac consequences of COVID-19.

Ethics. The study was carried out in compliance with medical research protocol from the Committee on Biomedical Ethics of the Tyumen Cardiology Research Center (protocol No. 159 of July 23, 2020).

Contribution:
Yaroslavskaya E.I. — the concept and design of the study, data collection and processing, writing and editing;
Romanenko D.A. — data collection and processing, writing and editing;
Gorbatenko E.А. — statistical data processing;
Klimova E.G. — statistical data processing;
Chaschin M.V. — the concept and design of the study.

Funding. The study had no funding.

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

Received: 14.05.2024 / Accepted: 19.06.2024 / Published: 31.07.2024

Introduction. According to the literature, exacerbation of chronic obstructive pulmonary disease (COPD) is a key factor that leads to an increase in the severity of the symptoms of the disease, deterioration of lung function, decreased exercise tolerance and, as a result, contribute to an increase in mortality. The prevention of exacerbations of COPD has social and economic significance and should be a primary task in the treatment of this disease. It is known that the use of fixed combinations improves patients’ adherence to therapy by about 2 times, which, in turn, leads to an increase in the effectiveness of treatment.

The study aims to evaluate the pharmacoeconomical effectiveness of triple therapy for chronic obstructive pulmonary disease using the example of a fixed triple combination of budesonide+glycopyrronium bromide+formoterol (BUD/GLI/FORM).

Materials and methods. 698,359 employees of a large transportation company participated in the study. 2,154 of whom had an updated diagnosis of COPD, and 193 cases of COPD were registered for the first time. The authors conducted a clinical and economic analysis taking into account the current recommendations of the Federal State Budgetary Institution «Center for Expertise and Quality Control of Medical Care» of the Ministry of Health, Russian Federation, published in December 2016. The authors have used methods such as cost estimation, budget impact analysis, and cost–effectiveness analysis. To conduct a pharmacoeconomical analysis, the researchers used data from clinical studies comparing the effectiveness of three types of therapy in patients with moderate and severe COPD on an outpatient basis. The cost of comparison drugs is taken from the official website of the state register of maximum selling prices. The researchers analyzed the costs of the employer in accordance with the Recommendations for heads of medical institutions and attending physicians, specialist doctors of the executive bodies of the Social Insurance Fund of the Russian Federation «Approximate terms of temporary disability in the most common diseases and injuries» (in accordance with ICD-10) (approved by the Ministry of Health of the Russian Federation and the Social Insurance Fund of the Russian Federation dated August 21 2000 No. 2510/9362-34, 02-08/10‑1977P). The authors determined the cost–effectiveness ratio (CER) using the formula: CER=DC/Ef, where DC (direct costs) is the direct cost of medical technology (cost of treatment, rubles); Ef is an indicator of the effectiveness of therapy, which is expressed in the percentage of patients who successfully completed the course, which allows us to evaluate the amount of cost to ensure stable remission in 1 patient.

Results. The results clearly indicate a significant reduction in financial losses of the enterprise for the absence of an employee due to temporary disability (TD) against the background of using a triple combination of BUD/GLI/FORM compared with alternative schemes. The economic effect amounted to more than 124 million rubles compared with the appointment of dual therapy DAX/DBA and more than 61 million rubles compared with the appointment of dual therapy IGCS/DDBA. The assessment of indirect costs in case of potential loss of working capacity and labor productivity as a result of exacerbation of COPD from the point of view of the macroeconomics of the region demonstrated a decrease in gross domestic product (GDP) losses in case of exacerbation and death among patients receiving BUD/GLI/FORM.

Conclusion. BUD/GLI/FORM therapy in a comparative study is dominant, characterized by excellent clinical efficacy and reduced overall costs associated with a decrease in the frequency of moderate and severe exacerbations of COPD.

Ethics. This study was performed in accordance with the rules of good clinical practice and the Helsinki Declaration, and did not require the conclusion of the Ethics Committee.

Contribution:
Rumyantseva O.I. — concept and design of the study, writing, editing;
Kostenko N.A. — collection and processing of material, editing;
Zemlyakova S.S. — collection and processing of material, editing.

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

Funding. The study had no funding.

Received: 07.05.2024 / Accepted: 25.06.2024 / Published: 31.07.2024

Hypersensitive pneumonitis (HP) is an inflammatory interstitial lung disease (ILD) that occurs in predisposed individuals in response to repeated exposure to various aerosol antigens. In 2020 and 2021, specialists made changes to the latest clinical recommendations, to the classification of HP, allowing to distinguish between fibrous and non-fibrous types of HP. The fibrous type is associated with the progression of the disease and an unfavorable prognosis. The diagnosis of HP and its division into types are based on a combination of clinical and anamnestic data, a high-resolution computed tomography (HRCT) picture, the results of cytological examination of bronchoalveolar lavage (BAL) and lung biopsy. Specialists also use lung function tests to determine the progression of the disease. The key diagnostic method is high-resolution computed tomography, which reveals signs of lung tissue pathology («frosted glass», mosaic density) and signs of damage to the small respiratory tract (centrilobular foci, air traps). In fibrotic HP, experts have identified signs of fibrosis: traction bronchiectasis, reticular changes, decreased lung volume, and the formation of a «cellular lung» is possible. Non-fibrotic HP is characterized by: lymphocytic cytogram type (more than 30% of the total number of cells), while in fibrotic HP lymphocytosis is less common. Experts often use lung biopsies for differential diagnosis with other diseases. In nonfibrotic HP, scientists evaluate the signs of involvement of bronchioles and adjacent alveoli in the inflammatory process, the nature of inflammatory infiltration and the presence of granulomas. Fibrotic HP has bronchiolocentric fibrosis, chronic interstitial pneumonia, peribronchiolar metaplasia and other signs. HP therapy includes the elimination of contact with the antigen, the administration of glucocorticosteroids and/or immunosuppressants, as well as antifibrotic therapy in the presence of a progressive variant of fibrous HP.

Contribution:
Suvorova O.A. — research concept and design, data collection and processing, writing the text, editing;
Trushenko N.V. — research concept and design, data collection and processing, writing the text, editing;
Samsonova M.V. — writing the text;
Chernyaev A.L. — writing the text;
Gordeeva A.A. — data collection and processing, writing the text;
Panina U.V. — data collection and processing, writing the text;
Babayan F.Z. — data collection and processing, writing the text;
Avdeev S.N. — research concept and design, editing.

Funding. The study had no funding.

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

Received: 06.02.2024 / Accepted: 09.06.2024 / Published: 31.07.2024

For the modern economic conditions of the development of the state and business of many groups of information systems specialists, an assessment of the class of working conditions of employees under intense computer load is relevant. Modern working conditions form a high voltage of the visual analyzer with a decrease in the functional capabilities of the body of workers, which can lead to the development of computer visual syndrome (CVS), refractive errors (progression of myopia).

The study aims to assess the working conditions at the workplaces of specialists with an intensive computer load in order to justify effective measures for the prevention of occupational and production-related diseases.

Specialists have conducted hygienic studies of working conditions in workplaces equipped with computers. Indoors, they measured temperature, movement speed and relative humidity, illumination, levels of ultraviolet radiation intensity, and brightness of the monitor’s work surface. The first subgroup of respondents consisted of specialists with an average office qualification level (278 people), the second subgroup consisted of IT specialists (278 people). In total, for the period 2019–2024, the authors surveyed 556 workplaces. They have carried out hygienic measurements of factors of the production environment and the labor process in workplaces equipped with modern computers in accordance with generally accepted methods.

The authors have identified the features of the work of IT specialists associated with a significant visual load: the time of using a computer reached 6 hours with an 8-hour work shift and a 24-day work schedule. Based on the conducted research, experts have established differences in the hygienic parameters of the production environment in the traditional form of labor organization (in organizations of various forms of ownership in Kislovodsk) and when working in a «remote system», i. e. outside the workplace of the employer.

During the monitoring of 2019–2024, scientists have established an excess of the level of hygienic standards, which is associated with the peculiarities of the professional activity of employees when hiring on a remote system: in terms of the microclimate of industrial premises, the intensity of ultraviolet radiation, electromagnetic radiation, in terms of visual parameters of computer monitors (brightness, contrast, etc.).

Ethics. The research was conducted in accordance with the principles of biomedical Ethics and approved by the local Ethics Committee of the Izmerov Research Institute of Occupational Health (Protocol No. 4 dated 04/14/2021). Each participant of the study submitted a voluntary written informed consent signed by him after explaining to him the potential risks and benefits.

Contribution:
Bukhtiyarov I.V. — the concept and design of the study;
Yushkova O.I. — writing, editing;
Afanasyeva Yu.F. — data collection and processing, text writing.

Funding. The study had no funding.

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

Received: 06.04.2024 / Accepted: 05.07.2024 / Published: 31.07.2024

The article tells about the problem of diagnosing vibration disease as a chronic occupational disease affecting the peripheral vascular, nervous and musculoskeletal systems as a result of prolonged exposure to industrial vibration. Due to the need for early detection of this pathology, the author proposed a large number of diagnostic tests aimed primarily at diagnosing changes in peripheral vessels and the nervous system.

There are results of a review of modern research methods devoted to the diagnosis of changes in the musculoskeletal system, osteoarthritis, lesions of periarticular tissues, lesions of peripheral nerves in patients exposed to vibration and patients with vibration disease. Due to the polymorphic clinical picture of the disease, there are currently diagnostic situations in which existing methods do not allow for a reliable diagnosis or differential diagnosis. Special attention is paid to the modern possibilities of ultrasound examination of joints, periarticular tissues and peripheral nerves in the diagnosis of manifestations of vibration disease.

The introduction of an ultrasound examination method into diagnostic practice will improve the quality of diagnosis of ostearthritis, periarthritis, tunnel neuropathies, followed by a timely choice of therapeutic and preventive tactics, which will play an important role in maintaining the health of those workers whose professional activities are associated with an increased level of vibration.

Funding. The work was carried out within the funds allocated for the fulfillment of the State task of the East-Siberian Institute of Medical and Ecological Research.

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

Received: 20.05.2024 / Accepted: 24.06.2024 / Published: 31.07.2024