Uticaj opterećenja različitim nivoima profesionalnog stresa na koncentraciju serumskih lipida službenika obezbeđenja

The aim of this work is to analyze the relationship between the level of professional stress and the concentration of total cholesterol, HDL cholesterol, LDL cholesterol and triglycerides in the serum of security employees. . The study included 415 security officers (exposed group) divided into four sub-groups and 150 administrative workers (control group). By applying a standardized questionnaire, the level of professional stress in their workplaces was calculated. To determine the serum lipid concentration in the all subjects, venous blood samples were taken in the morning after a twelve-hour food abstinence Security officers are exposed to a high level of professional stress, where the level of stress index depends on the type of the job they are engaged in. The highest values of the total index of professional stress, total cholesterol, LDL cholesterol and triglycerides were registered with the employees who transport money and those carrying firearms. The lowest total index of professional stress, total cholesterol, LDL cholesterol and triglycerides were registered with property security officers and persons who do not carry firearms. The correlation between the level of stress index at work, an increase in total cholesterol, LDL cholesterol, triglycerides and HDL cholesterol levels is statistically significant. We believe that there is a significant correlation between the level of the overall stress index at work and the risk of atherosclerosis in security officers.Cilj rada je analiza povezanosti nivoa profesionalnog stresa i koncentracija ukupnog holesterola, HDL holesterola, LDL holesterola i triglicerida u serumu službenika angažovanih na različitim vrstama obezbeđenja. Ispitivanjem je obuhvaćeno 415 službenika obezbeđenja (ispitivana grupa) podeljenih u četiri podgrupe i 150 administrativnih radnika (kontrolna grupa). Primenom standardizovanog upitnika, je izračunavan nivo profesionalnog stresa na njihovim radnim mestima. Radi određivanja koncentracije lipida u serumu od svih ispitanika je uziman uzorak venske krvi ujutru posle dvanaestočasovne apstinencije od hrane. Službenici obezbeđenja su izloženi visokom nivou profesionalnog stresa, pri čemu nivo indeksa stresa zavisi od vrste poslova na kojima su angažovani. Najviše vrednosti ukupnog indeksa profesionalnog stresa, ukupnog holesterola, LDL holesterola i triglicerida su registrovane kod službenika na obezbedjenju transporta novca sa nošenjem vatrenog oružja. Najniže vrednosti ukupnog indeksa profesionalnog stresa, ukupnog holesterola, LDL holesterola i triglicerida su registrovane kod službenika na obezbedjenju imovine i lica bez nošenja vatrenog oružja. Utvrđena je statistički značajna korelacija između nivoa indeksa stresa na poslu, povećanja vrednosti ukupnog holesterola, LDL holesterola, triglicerida i smanjenja nivoa HDL holesterola. Smatramo da postoji značajna povezanost između nivoa ukupnog indeksa stresa na poslu i rizika od ateroskleroze kod službenika obezbeđenja

The influence of professional stress in permanent working capability of workers with arterial hypertension and its complications

Arterial hypertension is widespread in the population of workers. Stress at work has a significant impact on the emergence of many psychosomatic diseases including arterial hypertension. The aim of this research is to show the influence of professional stress on the occurrence of arterial hypertension, its complications and the permanent working ability of exposed workers in construction. The survey covered 1900 construction workers. The standardized questionnaire has assessed the level of stress and professional stressors in their workplaces. The survey group consisted of 1350 workers whose level of total professional stress index (OSI) was over 60, and a control group of 550 workers with an OSI level below 60. The prevalence of arterial hypertension and its complications is statistically significantly more frequent in the examined than in the control group. In the investigated group, a statistically significant number of workers were registered, who, due to their complete loss of working ability, were sent to the disability commission. With an increase in OSI values above 71, the number of workers with complete loss of working capacity is significantly increased in relation to the number of workers who are capable of working. Professional stress is a significant factor that affects the occurrence of arterial hypertension, its complications on vital organs, which lead to a complete permanent loss of working ability of exposed workers in construction

Work stress related lipid disorders and arterial hypertension in professional drivers: A cross-sectional study

Background/Aim. Occupational stress is a term used to define ongoing stress that is related to the workplace. The study was conducted to determine association of occupational stress index (OSI) and its aspects with arterial hypertension and lipid disorders using data from a cross-sectional survey of male professional drivers. Methods. The cross-sectional study was performed in 439 professional drivers divided into groups (city- and intercity bus drivers, truck and taxi drivers). The OSI and OSI aspects (high demands, strictness, underload, extrinsic time pressure, noxious exposure, avoidance and conflict) were calculated using the standardized questionnaire. Determination of serum lipids, blood pressure (BP) and cardiovascular risk factors were done. Results. A significant difference in prevalence of diagnosed hypertension and dyslipidemia was found along with a difference in total OSI and OSI aspects among examined subgroups of drivers. A total OSI was highest in city, high in intercity bus drivers, and the lowest one in truck and taxi drivers (82.79 ± 3.5, 81.28 ± 3.7, 73.75 ± 3.5, 71.61 ± 4.4, respectively; p < 0.01). Similar pattern showed triglycerides (TG), total cholesterol (TC) and LDL cholesterol and BP, while HDL-cholesterol showed reverse order (p < 0.01). Logistic regression analyses with multiple OSI aspects adjusted for age and years of exposure showed associations of total OSI with arterial hypertension [OR 5.5; 95% CI (2.24-7.95)] and dyslipidemia [OR 1.43 95% CI (1.09-2.80)]. Underload was the most important OSI aspect associated with the arterial hypertension [OR 1.18; 95% CI (1.04-2.58)] and elevated LDL cholesterol [1.26; 95 CI (1.19-2.1)]. A total OSI had a significant association with elevated LDL cholesterol [2.64; 95% CI (1.19- 7.7)], triglycerides [OR 3.27; 95% CI (1.20-5.1)] and low HDL cholesterol [OR 3.29; 95% CI (1.8-5.8)] (p < 0.01). Conclusion. The study provides the evidence for the significant association of total OSI and underload with lipid disorders and elevated blood pressure in professional drivers, which could be a possible link between job stress and coronary heart disease. Regular periodical examinations and workplace interventions aimed to decrease total OSI and underload are important aspects in primary prevention and additional reduction of cardiovascular risk. [Projekat Ministarstva nauke Republike Srbije, br. 43012 i br. 41018

BIOCHEMICAL AND HISTOPATHOLOGICAL EFFECTS OF MOBILE PHONE EXPOSURE ON RAT HEPATOCYTES AND BRAIN

Microwave radiation MWR is widespread in human environment. The most frequent sources of MWR are mobile phones and cell towers. The effects of MWR are still unknown and there are insufficient data about long-term MWR effects on hepatocytes and brain structures.The aim of this paper was to investigate the biological effects of mobile phone microwave radiation on the brain and liver of experimental animals and to determine the increase in oxidative stress as a possible pathogenetic mechanism for harmful effects of long-term exposure.Wistar rats, 3 months old, were divided into two groups: I-rats constantly exposed to MWR (3 female and 2 male) and II-control animals without near source of electromagnetic field (EMF) (3 female and 2 male). The microwave radiation was produced by a mobile test phone (model NOKIA 3110; Nokia Mobile Phones Ltd.) connected to a Communication Test Set (model 4202S; Wavetek, Germany). A 900 MHz electromagnetic near-field signal for GSM (Global System for Mobile communication at 900 MHz, continuous wave, analog phone) system was used. The whole-body specific energy absorption (SAR) rate was estimated as 0.025-0.05 W/kg (E=9.8-18.3 V/m, B=4.8-8.6 µT). Rats were sacrificed after 3 months of MWR exposure. The liver and brain were fixed in 10% formaldehyde and paraffin sections were stained by HE. The biochemical analyses comprised the determination of serum activity of AST (Aspartate aminotransferase), ALT (Alanine transaminase), GGT (Gamma-glutamyl transpeptidase) and LDH (Lactate dehydrogenase), as well as determination of serum concentration of sodium, potassium and chloride. Lipid peroxidation was determined by measuring the quantity of malondialdehyde (MDA).Slightly increased number of micronuclei and discrete perivenular fatty changes were only histopathological findings in the liver of exposed rats. The discrete reduction of gray matter and reduced size and number of dendritic spines of Purkinje cells in cerebellum were notified as well. The serum activity of ALT was significantly increased (p<0.05), while activities of AST, GGT and LDH did not changed in the exposed rats. Potassium serum concentration was significantly higher in the exposed rats, while the concentration of sodium and chloride did not differ. The MDA concentration was significantly higher in the brain and liver tissues of MWR-exposed rats.The results in this study show significant increase in lipid peroxidation as a direct indicator of the hepatocytes and brain cells’ injury under a long-term (90 days) mobile phone microwave exposure. The hyperkalemia could be the possible systemic marker of impaired cells membrane fluidy and increased permeability, alongside with increased ALT activity as marker of hepatocelular damage. Disorders of hypothalamo- hypophyseal axis lead to disturbances in affective behaviour, but also to disturbances of neurovegetative functions, which leads to behavioral changes and increased appetite and weight gain in exposed animals

EARLY DETECTION OF THYROID DISEASE IN WORKERS PROFESSIONALLY EXPOSED TO NOISE THROUGH PREVENTIVE MEDICAL CHECK-UPS

The aim of the study was to test the influence of noise on the occurrence of thyroid disease. A group of examinees included the noise-exposed workers (300) who work in the production halls and the control group (50) doing administrative jobs in the office. The testing was performed by the service of occupational medicine, within regular control and periodic check-ups of the noise-exposed group and health systematic examinations of the control group. Some laboratory analyses of the thyroid hormone were used for the purpose of this study. The percentage of those with an increased thyroid activity in the control group is 2%, while in the group of workers exposed to noise it equals 6,8%. In the control group, the total number of those with a decreased thyroid function is 0,85% and 4,85% in the noise-exposed group. In the control group, the total number of workers with the changed thyroid function is 2,85%, while in the group exposed to noise, the total number of workers with the changed thyroid function is 11,65%. By comparing the number of workers having disturbances in the thyroid function from the control group to those from the noise-exposed group who have hearing nerve damage, it can be noticed that there is no statistically significant difference. There were 21 examinees that had subjective health complaints with the levels of hormones increased; 15 examinees had subjective health complaints while the levels of hormones were decreased, and 77 examinees had subjective health complaints with the levels of hormones within the normal range. The largest number of workers with a changed thyroid function had between 10 and 20 years of service. After analyzing the results, obtained in both control and noise-exposed groups, the conclusion was that the number of workers having problems with the thyroid activity is larger in the group exposed to noise in relation to the workers from the control group. These values are in correlation with the level of noise at the working place

Effects of L-ascorbic acid and alpha-tocopherol on biochemical parameters of swimming-induced oxidative stress in serum of guinea pigs

Background: The purpose of this study is to determine the effect of L-ascorbic acid and alpha-tocopherol as well as combination of these vitamins with or without exposure to physical exercise on intensity of lipid peroxidation, activity of xanthine oxidase, activity of total antioxidative system, concentration of glutathione, and activity of catalase in the serum of guinea pigs.Materials and Methods: The experimental measurements of intensity of lipid peroxidation, activity of xanthine oxidase, activity of total antioxidative system, concentration of glutathione, and activity of catalase were done in the serum of guinea pigs. The animals were exposed to the test load to achieve exhaustion and the test was terminated when the animal for the third time to sink into the water.Results: The results of this study demonstrated that endurance exercise of guinea pigs induced oxidative stress response in terms of increased lipid peroxidation and activity of xanthine oxidase in the serum of experimental animals. Our study investigated the antioxidant activity of L-ascorbic acid and alpha-tocopherol also measuring three protective markers in the serum: total antioxidant activity, content of glutathione and activity of catalase. The results obtained show that the vitamins influence the concentrations of above mentioned biochemical parameters, which points out their protective effect of swimming-induced oxidative stress.Conclusion: Single or combined administration of L-ascorbic acid and alpha-tocopherol caused significant inhibition of these markers indicating the important antioxidant activity of the vitamins. Results lead to conclude that the combined treatments with vitamins with or without exposure to physical exercise showed the clear synergistic effect.Key words: L-ascorbic acid, alpha-tocopherol, guinea pigs, oxidative stress,  biochemical parameter

Associations of fatty acids composition and estimated desaturase activities in erythrocyte phospholipids with biochemical and clinical indicators of cardiometabolic risk in non-diabetic Serbian women: the role of level of adiposity

Introduction: Fatty acids (FAs) composition and desaturase activities can be altered in different metabolic conditions, but the adiposity-independent associations with clinical and biochemical indicators of cardiometabolic risk are still unclear. This study aimed to analyze the associations of FAs composition and estimated desaturase activities with anthropometric, clinical, and biochemical cardiometabolic risk indicators in non-diabetic Serbian women, and to investigate if these associations were independent of the level of adiposity and other confounders. Methods: In 76 non-diabetic, otherwise healthy Serbian women, aged 24-68 years, with or without metabolic syndrome or obesity (BMI=23.6±5.6 kg/m2), FA composition in erythrocyte phospholipids was measured by gas-liquid chromatography. Desaturase activities were estimated from product/precursor FAs ratios (D9D:16:1n-7/16:0; D6D:20:3n-6/18:2n-6; D5D:20:4n-6/20:3n-6). Correlations were made with anthropometric, biochemical (serum glucose, triacylglycerols, LDL-C, HDL-C, ALT, AST, and their ratios) and clinical (blood pressure) indicators of cardiometabolic risk. Linear regression models were performed to test the independence of these associations. Results: Estimated desaturase activities and certain FAs were associated with anthropometric, clinical and biochemical indicators of cardiometabolic risk: D9D, D6D, 16:1n-7 and 20:3n-6 were directly associated, while D5D and 18:0 were inversely associated. However, the associations with clinical and biochemical indicators were not independent of the associations with the level of adiposity, since they were lost after controlling for anthropometric indices. After controlling for multiple confounders (age, postmenopausal status, education, smoking, physical activity, dietary macronutrient intakes, use of supplements, alcohol consumption), the level of adiposity was the most significant predictor of desaturase activities and aforementioned FAs levels, and mediated their association with biochemical/clinical indicators. Vice versa, desaturase activities predicted the level of adiposity, but not other components of cardiometabolic risk (if the level of adiposity was accounted). While the associations of anthropometric indices with 16:1n-7, 20:3n-6, 18:0 and D9D and D6D activities were linear, the associations with D5D activity were the inverse U-shaped. The only adiposity-independent association of FAs profiles with the indicators of cardiometabolic risk was a positive association of 20:5n-3 with ALT/AST ratio, which requires further exploration. Discussion: Additional studies are needed to explore the mechanisms of the observed associations

The influence of specific aspects of occupational stress on security guards' health and work ability: detailed extension of a previous study

In our earlier study of security guards, we showed that higher occupational stress was associated with health impairments (metabolic syndrome, diabetes, hypertension, cardiovascular diseases) and work disability. The aim of this study was to further explore the association of specific occupational stressors with health impairments and work disability parameters in 399 Serbian male security guards (aged 25-65 years). Ridge linear regression analysis revealed that, after controlling for age, body mass index, and smoking status, professional stressors including high demands, strictness, conflict/uncertainty, threat avoidance and underload were significant positive predictors of fasting glucose, triglycerides, total and LDL cholesterol, blood pressure, heart rate, Framingham cardiovascular risk score, and temporary work disability. The security profession is in expansion worldwide, and more studies are needed to establish precise health risk predictors, since such data are generally lacking

Vitamin D Status and Its Correlation With Anthropometric and Biochemical Indicators of Cardiometabolic Risk in Serbian Underground Coal Miners in 2016

The status of vitamin D in underground working coal miners and its association with their cardiometabolic health is rarely studied. This study aimed to examine vitamin D (VitD) status in Serbian underground coal miners and to correlate it with anthropometric and laboratory indicators of cardiometabolic risk. Nutritional data (food frequency questionnaire, FFQ, and two times repeated 24 h recall), anthropometric data (including segmental analysis by bio-impedance analyzer TANITA BC-545N), arterial tension, and biochemical and hematological data of 103 coal miners (aged 22–63 years) were correlated with their late summer (early September) serum 25 (OH)D levels (measured by HPLC). 68.9% of the studied coal miners were overweight/obese, and 48.5% had metabolic syndrome. Their mean VitD nutritional intakes were low: 5.3 ± 3.8 μg/day (FFQ) and 4.9 ± 8 μg/day (24 h recalls), but their mean serum 25 (OH)D levels were surprisingly high (143.7 ± 41.4 nmol/L). Only 2.9% of the coal miners had 25(OH)D levels lower than 75 nmol/L (indicating an insufficient/deficient status), while 63.2% had values above 125 nmol/L (upper optimal limit), and even 10.7% had values above 200 nmol/L. There were no statistical differences in 25 (OH)D levels in the coal miners with or without metabolic syndrome (or overweight/obesity). Interestingly, 25(OH)D levels had significant positive correlations with body mass index (BMI), fat mass (FM), fat mass percentage (FM%), limbs FM%, serum triglycerides, GGT, AST, ALT, and ALT/AST ratio, and had significant negative correlations with serum HDL-cholesterol and age. All these correlations were lost after corrections for age, FM, FM%, and legs FM%. In Serbian coal miners, high levels of early September VitD levels were observed, indicating sufficient non-working-hour sun exposure during the summer period. Furthermore, the unexpected positive correlations of VitD levels with anthropometric and biochemical parameters indicative of obesity, metabolic syndrome, and fatty liver disease were found. More research is needed on the VitD status of coal miners (particularly in the winter period) and its relationship with their cardiometabolic status

Model za predviđanje bioloških efekata zračenja mobilnih telefona: numerički rezultati apsorbirane energije povezani s realnom strukturom dobivenom metodom MRI

The nature of an electromagnetic field is not the same outside and inside a biological subject. Numerical bioelectromagnetic simulation methods for penetrating electromagnetic fields facilitate the calculation of field components in biological entities. Calculating energy absorbed from known sources, such as mobile phones when placed near the head, is a prerequisite for studying the biological influence of an electromagnetic field. Such research requires approximate anatomical models which are used to calculate the field components and absorbed energy. In order to explore the biological effects in organs and tissues, it is necessary to establish a relationship between an analogous anatomical model and the real structure. We propose a new approach in exploring biological effects through combining two different techniques: 1) numerical electromagnetic simulation, which is used to calculate the field components in a similar anatomical model and 2) Magnetic Resonance Imaging (MRI), which is used to accurately locate sites with increased absorption. By overlapping images obtained by both methods, we can precisely locate the spots with maximum absorption effects. This way, we can detect the site where the most pronounced biological effects are to be expected. This novel approach successfully overcomes the standard limitations of working with analogous anatomical models.Numeričke bioelektromagnetne simulacijske metode prodrlih elektromagnetnih polja koriste se za izračunavanje komponenata polja u biološkim jedinkama. Elektromagnetno polje nije jednako izvan i unutar biološkog subjekta. Izračunavanje energije apsorbirane iz poznatog izvora, kao što su mobilni telefoni u području glave, preduvjet je za ispitivanje biološkog utjecaja elektromagnetnog polja. Pri ovim istraživanjima koriste se približni anatomski modeli i na osnovi njih se izračunavaju komponente polja i apsorbirana energija. Nužno je uspostaviti vezu između odgovarajućih približnih anatomskih modela s realnom strukturom, kako bi se mogli istraživati biološki efekti u dijelovima organa i tkiva. Zbog toga se u ovom radu predlaže novi pristup istraživanju bioloških efekata. U osnovi metode je kombinacija dviju različitih tehnika: 1) numeričke elektromagnetne simulacije kojom se izračunavaju komponente polja u približnom anatomskom modelu i 2) MRI metoda (Magnetic resonance imaging) kojom se precizno lociraju mjesta s povišenom apsorpcijom. Kombiniranje se postiže preklapanjem slika dobivenih jednom i drugom metodom, čime se utvrđuje precizna lokacija mjesta s maksimalnim efektima apsorpcije. Na taj način mogu se pronaći mjesta na kojima bi trebao biti najizraženiji biološki učinak. Novi pristup uspješno prevladava ograničenja koja su postojala pri radu s približnim anatomskim modelima