Introduction. This article is a continuation of the publication of the experimental studies results of prevention of acute decompression sickness (aDCS) in laboratory animals by the method of liquid respiratory desaturation (LRDS). LRDS is a method of preventing decompression disorders by the excretion of metabolically indifferent gases (in particular nitrogen) from the body during spontaneous respiration with liquid or artificial liquid lung ventilation (ALLV), by dissolved gas concentration gradient "from tissues to respiratory fluid". The method allows to provide rapid desaturation of the body from metabolically indifferent gases in the process of liquid respiration before and/or during decompression, thereby creating conditions for application of ultra-fast decompression profiles without the risk of decompression disorders.

The aim of the study was to confirm the possibility of LRDS being a method of DCS prevention on large laboratory animals (minipigs).

Materials and methods. The studies were performed on Wiessenau minipigs (n=8) — male and female, aged 4–5.5 months and weighing 7.1–11.2 kg. Animals of the control (n=4) and experimental (n=4) groups were subjected by compression by keeping in an air environment under high pressure (absolute 0.5 MPa for 60 minutes) to saturate tissues with indifferent gas (nitrogen). After compression experimental group was exposed to 30-minute ALLV with a liquid (perfluorodecalin) saturated with an oxygen under normobaric conditions. Air environment pressure during procedure of artificial lung ventilation was kept at 0.5 MPa. Decompression of the control and experimental groups was carried out in non-stop manner for 80 and 40 seconds respectively. The investigation of severity of clinical manifestations of DCS (changes in hemodynamic and respiratory parameters) including ultrasonic examination of gas bubbles in the heart and large vessels of the liver and as well as survival of animals in groups and pathoanatomical changes was performed.

Results of the study. Clinical manifestations, ultrasonic scanning of the heart and venous vessels of the liver, as well as morphological examination data indicated the development of severe acute post-decompression disorders (PDD) in animals of the control group, which caused deaths in 100% of cases. Meanwhile all animals in experimental group survived and their state was stable. According to ultrasonic examination, the presence of small number of gas bubbles in the right-side heart chambers and liver's venous vessels being noted, but they disappeared after several hours. Deviations of the respiration's parameters function from background values (shortness of breath of a mixed type with the participation of auxiliary muscles, etc.) observed from the 2nd to the 4th day after ALLV, as well as compensatory reactions from the cardiovascular system (heart rate variability and instability of hemodynamic parameters) were caused by ALLV.

Conclusions. Compressed air exposure 0.5 MPa for 60 minutes followed by 80 seconds of non-stop decompression allows to provoke the severe acute PDD minipigs model, manifested by pronounced intravascular gas formation, the development of acute respiratory and cardiovascular insufficiency causing the development of adverse outcomes.

The ultrasound method of visual assessment of intravascular gas formation severity, adapted for minipigs, together with the dynamics of changes in the indicators of respiratory and cardiovascular systems makes possible to assess not only state of animal under anesthesia, but also the effectiveness of PDD prevention measures.

The usage of ALLV with PFC liquid completely saturated with 100% oxygen under normobaric conditions makes possible partial removal of indifferent gas (nitrogen) dissolved in tissues of experimental animals during exposition in a compressed air environment before decompression and thereby carry out the prevention of DCS by LRDS method. It makes possible to implement successfully ultra-fast decompression profiles, incompatible with life in the control group.

The state of animals from experimental group after LRDS is characterized by lung impairment caused by ALLV in hyperbaric conditions accompanied by temporary changes of external respiration function and compensatory reactions of cardiovascular system, observed during first 4 days.

Ethics. The study was conducted in accordance with the ethical principles of the Declaration of Helsinki. The Clinical Study Protocol was approved by local Ethics Committee of The Federal State Budgetary Scientific Institution «Izmerov Research Institute of Occupational Health».

Funding. The study was funded by The Advanced Research Foundation, Moscow, Russian Federation.

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

Received: 18.13.2024 / Accepted: 25.03.2024 / Published: 05.04.2024

Introduction. The article tells about the widespread use of infrared lasers in the fields of human activity. The constantly increasing power of laser installations leads to an increased risk to the health of large groups of workers. Current hygiene standards do not provide adequate eye protection from the harmful effects of this factor.

The study aims are a scientific justification for improving the maximum permissible level (MPL) of infrared laser radiation.

Materials and methods. To generalize and systematize the results of experimental studies and mathematical modeling to determine the threshold values of the harmful effects of infrared laser radiation on eyeball tissue, the authors used analytical methods.

Results. Far infrared laser radiation can pose a danger not only to the cornea, but also to the retina. One of the important indicators affecting the depth of penetration of laser radiation into the structures of the eye and the severity of lesions is the absorption coefficient of the medium. Based on mathematical modeling of the thermochemical destruction of eye tissues, the researchers determined the threshold values of the harmful effects of far-infrared laser radiation, confirmed by the results of experimental studies. The scientists justified the need to introduce a higher coefficient of hygienic reserve in determining the maximum permissible level and recommended new proposals for the hygienic regulation of far-infrared laser radiation.

Conclusion. The introduction of new maximum permissible levels will provide more reliable eye protection from far infrared laser radiation.

Ethics. This study did not require the conclusion of the Ethics committee.

Contribution:
Paltsev Yu.P. — the concept and design of the study, data collection and processing, writing, editing;
Pokhodzey L.V. — research concept and design, data collection and processing, text writing, editing;
Zheltov G.I. — concept and design of research, data collection and processing.

Funding. The study had no funding.

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

Received: 04.03.2024 / Accepted: 14.03.2024 / Published: 05.04.2024

Introduction. Uncomfortable working conditions and excessive professional loads on the shoulder joints cause a high prevalence of degenerative-dystrophic changes in the periarticular tissues. Calcifying tendinitis and bursitis occupy a special place, characterized by multifocal accumulation of calcium phosphate crystals in tendons, mucous bags and muscles. The study is devoted to solving the problem of optimizing the X-ray diagnostics of the evolution of calcifying tendinobursopathy of the shoulder (CTS) in the dynamic assessment of the effectiveness of extracorporeal shock wave therapy.

The aims of the study to optimize the X–ray diagnosis of calcifying tendinobursopathy of the shoulder in people working under the influence of adverse production factors.

Materials and methods. The authors conducted a comparative retrospective analysis of the results of a comprehensive dynamic clinical and X-ray examination of 155 able-bodied men aged 35-57 years with an average work experience of 14.5±2.7 years (miners, loaders, bricklayers) examined for pain syndrome and dysfunction in the shoulder joint. The main group (65 people) are patients with CTS clinic, the presence of calcifications in the periaricular tissues of the rotator cuff and in the biceps muscle of the shoulder, evaluated in dynamics after shock wave therapy (SWT) of the shoulder in the phases of rest, resorption and recovery. The comparison group (90 people) consisted of patients with the absence of instrumentally detectable signs of multifocal accumulation of calcium phosphate crystals in the periarticular tissues of the shoulder. The study included patients whose routine conservative treatment proved ineffective. The following criteria for the effectiveness of therapy were identified: pain at rest, measured using a visual analog scale (VAS); dimensions (calcification area (in mm²)); optical density and calcification density gradient. Specialists evaluated the data at the initial stage of the study before the use of therapy, immediately after treatment and 12 months after the final SWT session.

Results. In patients of the main group with the presence of CTS, the main manifestations of shoulder-scapular periarthritis (SSP) both in the main group and in the comparison group were moderately pronounced, however, the frequency of detection of the main SSP syndromes, primarily rotator cuff lesion, as well as background pathology (arthrosis of the shoulder joint) and acromioclavicular joint) were significantly higher in the main group. The effectiveness of SWT was demonstrated by regression of pain syndrome and positive dynamics of density characteristics of periarticular tissues of shoulder joints in areas of interest (in anatomotopographic projections of localization of tendons, mucous bags and muscles). In all patients of the main group, the decalcification process was characterized by both a visually perceptible pattern of disintegration and a decrease in its area, and a decrease in optical density immediately after the end of treatment. In 36.9% of patients, 12 months after the start of SWT, the X-ray and X-ray densitometric picture confirmed the prolongation of the decalcification process up to complete lysis of foci and calcification sites.

Conclusions. In a comprehensive assessment of the effectiveness of CTS therapy, along with traditional X-ray diagnostics, special methodological techniques of radiometry (X-ray diffraction and X-ray densitometry in areas of interest) can be used, allowing for more accurate and more objective reflection of the direction of the dynamics of changes.

The use of X-ray calcifications in the arsenal of methodological techniques, such as area, optical density and optical density gradient, can significantly improve the quality of diagnosis and avoid the use of computed tomography and an increase in radiation exposure to the patient.

High-energy extracorporeal shockwave therapy is largely able to solve the problem of treating resistant forms of calcifying tendinobursopathy of the shoulder.

Ethics. The study did not require the conclusion of the Ethics committee.

Contribution:
Druzhinin V.N. — research concept and design, data collection and processing, text writing;
Suvorov V.G. — data collection and processing;
Slavinsky A.A. — editing;
Yesin E.V. — statistical analysis.

Funding. The study had no funding.

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

Received: 05.02.2024 / Accepted: 27.02.2024 / Published: 05.04.2024

The article provides an overview of modern scientific approaches to assessing the state of neurofunctional activity of the brain under the professional influence of physical and chemical factors is presented, carried out using bibliographic databases Scopus, MedLine, Web of Science, PubMed, The Cochrane Library, RSCI, Cyberleninka, Google Academy, Index Copernicus, SJR, Science Direct, Arxiv.Org. The work reflects the results of research by domestic and foreign scientists stating the fact of violations of neurobioelectric activity, cerebral hemodynamics, afferent conductive structures, cytokine and neuropsychological status in patients with vibration disease, sensorineural hearing loss, chronic mercury intoxication. There are prospects for using neuroenergic mapping with registration of the level of constant potential. The effects of biofeedback training (biofeedback method) on the reference reaction in order to stabilize and activate the neurofunctional activity of the brain in the treatment of neurological patients are reflected. The analysis of literary sources allowed us to substantiate the need to use artificial intelligence technologies to automate processes as a highly sensitive and specific method of detecting occupational pathology. The presented data indicate the relevance of the problem of studying disorders of neurofunctional activity, the relationship between the nervous and immune systems under the influence of vibration, noise, metallic mercury to improve the criteria for diagnosing lesions of the central nervous system.

Funding. The finding was carried out within the Framework of the State Assignment for Fundamental and exploratory scientific research.

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

Received: 13.02.2024 / Accepted: 27.03.2024 / Published: 05.04.2024

The preservation and strengthening of the health of the able-bodied population is the most important indicator of the socio-economic potential of the country.

A modern working woman experiences the complex impact of adverse factors of the production environment and the labor process, which are potentially dangerous to health, contribute to the formation of production-related and occupational diseases.

The study aims to analyze the occupational health risk of women employed in jobs with harmful working conditions at the processing plant of the mining and processing plant and the petrochemical complex of the Republic of Bashkortostan.

Materials and methods. The authors studied the state of health by analyzing the occupational risk of female workers in contact with harmful production factors of a processing enterprise (407 people) and a petrochemical complex (473 people). The experts used clinical, functional, clinical and statistical research methods in their work and analyzed the levels and structure of chronic non-communicable diseases to determine the degree of industrial conditionality. The calculations were performed using the Microsoft Excel program.

The combined effect of a complex of harmful production factors of the mining and processing plant (dust of polymetallic ores, chemicals, noise and severity of labor — class of working conditions 3.1) contributes to the development of chronic non-communicable diseases in female workers in 80.3±2.0% of cases, versus 54.6±4.4% of cases in the control group. A number of identified diseases have the character of production-related, while a very high degree of its conditionality is characteristic of diseases of the musculoskeletal system and connective tissue (RR — relative risk = 4.3, EF — etiological proportion = 75%), a high degree was inherent in respiratory diseases (RR=3.1; EF=67.7%). Diseases of the circulatory system (RR=1.6, EF=37.5%) and diseases of the nervous system (RR=1.58, EF=36.7%) had an average degree of occupational
conditionality.

In the workers of the main group of the petrochemical complex, chronic non–communicable diseases were diagnosed significantly more often than in the control, respectively — 84.0±1.7 and 67.0±3.5% of cases, p<0.01. The combined effect on the workers of the complex of chemicals in combination with the intensity of the labor process associated with the 3-shift nature of work (class of working conditions 3.1), was the cause of the industrial conditionality of diseases of the nervous system, circulatory system, blood, digestive organs of moderate degree.

Female employees of the enterprises of the concentrating plant of the mining and processing plant and the petrochemical complex, engaged in work with harmful working conditions, represent a "risk group" for the occurrence of changes from various organs and systems, depending on the current etiological production factors. Based on the indicators of the degree of occupational conditionality of a number of diseases in female workers, mining and petrochemical complexes belong to industries with a high and medium occupational risk of health disorders.

Ethics. The survey of female employees was conducted with their informed consent, approved by the bioethical committee of the Institute. The fundamental documents are: "Ethical principles of conducting scientific medical research with human participation" (amendments 2008) of the Helsinki Declaration, as well as "Rules of Clinical Practice in the Russian Federation" (approved by Order of the Ministry of Health dated 06/19/2003 No. 266).

Contribution:
Gainullina M.K. — the concept and design of the study, writing the text, editing;
Valeeva E.T. — data collection and statistical processing, material analysis, text writing, editing;
Karamova L.M. — editing, working with literary sources;
Safin V.F. — material collection and statistical data processing;
Karimova F.F. — collection of material and statistical data processing.

Funding. The study had no funding.

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

Received: 13.01.2024 / Accepted: 15.02.2024 / Published: 05.04.2024

The formation of an evidence base for regulatory documents in the field of preliminary and periodic medical examinations is one of the urgent tasks of occupational health in the coming years. In the process of transition to a risk-based approach in occupational health, including in determining suitability for work, objective verification of risk is necessary, and the decision on suitability should be made on its basis. Suitability for work in the unique conditions of the highlands remains one of the least studied topics, since there are only isolated observational studies, the results of which are also not taken into account in the traditional approach of determining suitability. The article provides a brief overview of the association of smoking with various outcomes when working in the highlands. Smoking significantly worsens the prognosis of all outcomes studied in these studies, including even the likelihood of quitting work. The article concludes that it is necessary to plan studies of various outcomes, which can be used as a basis for supplementing and changing the regulatory framework for conducting medical examinations of employees. Particular attention is paid to the need to take into account, among other risk factors, a comprehensive risk assessment when determining suitability for work in mining in the highlands.

Ethics. The study did not require permission.

Contribution:
Strizhakov L.A. — study conceptualization and design, editing;
Brimkulov N.N. — manuscript drafting, editing;
Babanov S.A. — study conceptualization and design, manuscript drafting.

Funding. The study had no funding.

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

Received: 04.02.2024 / Accepted: 27.02.2024 / Published: 05.04.2024

The professional activity of a person, depending on the working conditions, modifies the regulation of a single homeostatic mechanism, ultimately forming a breakdown of adaptation associated with an imbalance of immunological
parameters.

The study aims to evaluate changes in the surface molecules of leukocytes of the immune system specifically induced by the presence of lanthanides in workers in the production environment.

The authors examined 88 people working in the metallurgical industry. The observation group consisted of 24 people with an average work experience of 7.4±0.9 years, the comparison group included 64 people with an average work experience of 7.3±0.9 years. The scientists determined the identification of membrane markers (CD11a, CD277⁺, CD304⁺) by flow cytometry, and they also identified specific IgG to lanthanides by allergosorbent testing.

Excessive concentrations of lanthanides in the blood are formed in workers of the titanium and rare metals recovery and distillation workshop, which are reliably associated with indicator indicators of cellular differentiation of immune regulation clusters: inhibition of expression of immunological phenotypes CD11a, CD304⁺, CD277⁺, hyperproduction of specific IgG class reagins to lanthanides. The established immunological scenario is characteristic of the phenotypic characteristics of classical dendritic cells involved in autoimmune inflammatory reactions during the formation of vascular disorders of the central nervous system in workers in these production conditions.

The results obtained indicate that under conditions of industrial exposure to rare earth metals (lanthanides), workers in the workshop for the recovery and distillation of titanium and rare metals form maladaptive processes of disorders of immune regulation and expression of mediators of cellular differentiation, the markers of which include inhibition of cellular immunity associated with neurovascular mediators (CD11a, CD277⁺, CD304⁺), hyperproduction of specific IgG to lanthanides.

Ethics. The study was approved by the Ethics committee of Federal Scientific Center for Medical and Preventive Health Risk Management Technologies. All patients were informed about the purpose of the study, and voluntary informed consent was obtained.

Contribution:
Dolgikh O.V. — research concept and design;
Shirinkina A.S. — data collection and processing;
Alikina I.N. — data collection and processing;
All authors — writing of the text, editing.

Funding. The study had no funding.

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

Received: 13.02.2024 / Accepted: 22.03.2024 / Published: 05.04.2024