Search

Currently, the Kurchatov Laser-Synchrotron Complex is conducting research on the interaction of powerful femtosecond laser radiation with matter. The purpose of these studies is to develop new techniques and approaches for the characterization of high-temperature plasma, X-rays and particle acceleration, which can be the basis for the work planned within the framework of the synchrotron-neutron project. Laser-driven X-ray production, electron acceleration, nuclear fusion, ultrafast structural dynamics of nanoparticles in intense laser fields remains an active research topic, aimed at generating advanced controllable sources. [ABSTRACT FROM AUTHOR]

Study Purpose: To conduct a cross-sectional study on the structural and functional characteristics of various parts of skin microcirculation in working-age men with newly diagnosed hypertension (HTN)., Materials and Methods: The study included 118 male participants (ages 30 to 60) who were not regularly taking any medicine, had no medical complaints, and subjectively considered themselves healthy at the time of study. All participants underwent a cross-sectional comprehensive medical examination. The following tests were performed: complete blood count, biochemical blood tests, video capillaroscopy (VCS), laser Doppler flowmetry (LDF) and photoplethysmography (PPG) on the left hand fingers, determination of flow-mediated vasodilation of the brachial artery, echocardiography, ultrasound of extracranial and femoral arteries, 24-h ambulatory blood pressure monitoring (ABPM). According to ABPM data, the participants were divided into two equal groups called a control group(CG) and a hypertension group(HG). There were 59 participants with normal BP in CG, and 59 participants with newly diagnosed HTN in HG., Results: Nailfold VCS of the ring finger revealed no significant differences between the groups at the level of exchange microvessels. According to LDF data, there was no decrease in tissue perfusion and signs of an increase in the activity of endothelial, neurogenic, and myogenic regulation of the tone of precapillary arterioles in the HTN group. According to PPG of the index finger, in contrast to CG, HTN participants had significantly higher values of the following parameters: normalized augmentation index (Alp75) - 3.8 % and - 5.25 % (p < 0.005), stiffness index (SI) - 7.6 m/s and 7.35 m/s (p < 0.05), reflection index (RI) - 36.5 % and 28.4 % (p < 0.005), respectively., Discussion: Working-age men in the early stage of HTN have neither capillary rarefaction nor an increase in the tone of skin precapillary arterioles. The largest contribution to peripheral vascular resistance in the onset of HTN is most likely made by large muscular arterioles, in which the neurogenic regulation of vascular tone predominates., Competing Interests: Declaration of competing interest The work was carried out within the State Assignment No. 121021100129-2 of the Ministry of Healthcare of Russian Federation. All authors declare no conflict of interest., (Copyright © 2022 Elsevier Inc. All rights reserved.)

This year marks 30 years of close collaboration between a consortium of institutions, namely, the Northwest Public Health Research Center, Saint-Petersburg (NWPHRC); the Institute of Community Medicine (ICM) of UiT (The Arctic University of Norway, Tromsø); the National Institute of Occupational Health (NIOH), Oslo; the University Hospital of Northern Norway (UNN) at Tromsø; and McMaster University (MU), Hamilton, ON, Canada. During the early years of cooperation, Dr. Chashchin was the Director of the Scientific Laboratory of the North-West Public Health Centre Branch of the NWPHRC located in the town of Kirovks in the Murmansk Region. The primary focus of this long-standing collaboration was to assess and address issues that are important for maintaining the health of the population living in the border areas of Russia and Norway and included the reduction of occupational health risks among workers employed in mining, metallurgical and machine-building enterprises located in the north-western region of Norway and the adjoining Kola Peninsula in Russia. These industrial activities constituted essential components of the local industries. The ongoing Russian-Norwegian cooperation in the field of occupational medicine is an excellent example of the effective combination of intellectual potential and research technologies of multiple countries. It has resulted in the development of a scientifically based set of measures for practical implementation, contributing to the improvement of working conditions and preservation of the health of workers employed at enterprises where the joint research was carried out.

The aim of the study was to assess temporal trends in health risks related to most common persistent contaminants, including polychlorinated biphenyls (PCBs), dichloro-diphenyl-trichloroethanes (DDTs), lead (Pb), as well as mercury (Hg) among indigenous peoples living in coastal areas of Chukotka in Arctic Russia. This is examined in relation to exposure pathways and a range of social and behavioral factors capable of modifying the exposure to these contaminants, including place of residence, income, traditional subsistence, alcohol consumption, and awareness of risk prevention. The primary exposure pathway for PCBs is shown to be the intake of traditional foods, which explained as much as 90% of the total health risk calculated employing established risk guidelines. Nearly 50% of past DDT-related health risks also appear to have been contributed by contaminated indoor surfaces involving commonly used DDT-containing insecticides. Individuals who practiced traditional activities are shown to have experienced a 4.4-fold higher risk of exposure to PCBs and a 1.3-fold higher risk for DDTs, Pb, and Hg. Low income, high consumption of marine mammal fat, alcohol consumption, and lack of awareness of health risk prevention are attributed to a further 2- to 6-fold increase in the risk of PCBs exposure. Low socioeconomic status enhances the health risks associated with exposure to the persistent contaminants examined.

Introduction: Studies have shown that welders have increased cardiovascular mortality. This may be due to airborne particulate matter (PM) exposure. Elevated levels of PM in polluted urban air have been associated with increased cardiovascular mortality and morbidity. This study seeks to explore potential mechanisms for the increased cardiovascular mortality in welders., Methods: Seventy welders were compared to 74 referents. Exposure to PM was assessed by personal full-shift sampling of work room air the last 2 days before collection of blood samples. Selected biomarkers of pro-coagulant activity, endothelial/platelet activation and systemic inflammation were determined in the samples., Results: The welders had been occupationally exposed to PM for 15 years on average. The geometric mean current exposure to PM was 8.1 mg/m 3 . They had statistically significantly higher concentrations of TNF-α, P-selectin, CD40L, prothrombin fragment 1 + 2 and D-dimer than the referents. Increasing concentrations of D-dimer and CD40L were observed by increasing current exposure to PM., Discussion: The study shows that welders highly exposed to welding PM were in a pro-thrombotic state with increased thrombin generation and consequently higher D-dimer concentrations. The welders had also increased endothelial/platelet activation as compared to the referents. These alterations are compatible with increased cardiovascular mortality as previously reported among welders.

Purpose: There is a lack of knowledge about neurobehavioral performance among patients with manganism and how their performance differs from that of idiopathic Parkinson disease patients (PD). This study was initiated with the aim to describe and compare neurobehavioral performance among patients diagnosed with manganism, PD and a group of referents., Materials and Methods: Neurobehavioral performance was assessed in 34 patients diagnosed with manganism, 13 with PD, and 43 healthy workers (turners/fitters) who served as the reference group. Seventeen of the manganism patients had also been tested approximately 65 months previously., Results: Manganism patients scored substantially more poorly than referents on tests for motor speed, manual dexterity and balance. They also performed more poorly than the PD patients on the postural sway test. In contrast, the PD patients had higher postural tremor intensity with narrower frequency dispersion than manganism patients. The pattern of neurobehavioral performance was more asymmetrical in PD compared to manganism patients, in particular when testing for tremor intestity, grooved pegboard and static steadiness, indicating lateralized impairment in the PD patients. The amount of bradykinesia was comparable between the patient groups. Neurobehavioral performance deteriorated slightly among 17 manganism patients followed for 65 months compared with the age-related decline among referents., Conclusions: Patients with manganism had severe bradykinesia and balance disturbances, but only slight postural tremor. In contrast, PD patients had significant postural tremor and bradykinesia, but only slight balance disturbances. Their neurobehavioral performance indicated lateralized impairment, more unilateral. Neurobehavioral performance deteriorated slightly in manganism patients during a 65-month follow-up.

The bio-accessibility of 14 elements in welding fume particulate matter was investigated in 325 personal air samples collected during welding in two shipyards and one factory producing heavy machinery. The apparent solubility in a synthetic lung lining fluid (Hatch's solution) was used as proxy for the bio-accessibility. The Hatch solubility of the different elements was highly variable with a median < 1% for Al, Fe, Pb, Ti, between 4 and 6% for Co, Cr, Ni, V, W, between 13 and 27% for Cd, Cu, Mn, Zn, and 41% for Mo. For many elements, the solubility varied over a wide range of several tens of percent. The welding techniques used influenced the solubility of Co, Cr, Cu, Mn and V significantly. The plants investigated (i.e., the welded materials and used electrodes) had a significant influence on the solubility of Co, Cr, Cu, Mn, Mo, V and W. According to principal component analysis (PCA), the variation in solubility can be described by four components, which explain 69% of the variance. The first principal component mostly comprises elements that can predominantly occur as divalent cations, the second principal component elements often forming oxyanions. The principal components are independent of the absolute value of the Hatch solubility. The results of PCA indicate that the co-variation of Hatch solubility is mainly controlled by the most soluble compounds in contrast to the absolute value of apparent solubility, which is strongly influenced by the distribution of the elements between compounds with different equilibrium solubilities. The observed large variability and the significant differences between welding techniques and plants clearly show that the bio-accessibility cannot be obtained from the literature but has to be studied experimentally at each location of interest.

Background: One of the most worrying consequence of the production and use of persistent organohalogen pollutants (POPs) is the high accumulation in Arctic populations because of long-range transport. Study of the effects in these populations may illustrate human impacts that are difficult to assess in other locations with lower exposure to these compounds and more diverse pollutant influences., Objective: We aimed to identify the main maternal characteristics influencing on the accumulation of these compounds and the effects on the newborns in a highly exposed Arctic population (Chukotka, Russia)., Methods: Organochlorine and organobromine compounds were analysed in maternal venous serum (n = 250). The study included data on residence, educational level, age, parity and body mass index (BMI) from self-reported questionnaires and measured anthropometric characteristics of newborns., Results: Concentrations of β-hexachlorocyclohexanes, hexachlorobenzene, 4,4'-DDT and polychlorobiphenyls were high when compared with those generally found in adult populations later than year 2000. The polybromodiphenyl ethers were negligible. These POP concentrations were higher than in Alaska and Arctic Norway and similar to those in Canada. The Chukotka mothers living in inland areas showed significant lower concentrations than those living in the coast (p < 0.001) except for 4,4'-DDT. The population from the Chukotsky District, a specific coastal area, showed the highest concentrations. Residence was therefore a main concentration determinant (p < 0.001) followed by maternal age, and in some cases parity and BMI (p < 0.05). 4,4'-DDT showed an association with the anthropometric characteristics of the newborns (p < 0.05). Mothers with higher 4,4'-DDT concentrations had longer gestational ages and gave birth to infants with higher weight and length., Conclusions: The maternal accumulation patterns of POPs were mainly related with residence. Most of these compounds were found in higher concentration in women living at coastal areas except 4,4'-DDE and 4,4'-DDT which were of inland origin. This last pesticide was the pollutant showing positive associations with gestational age and newborn's weight and length. To the best of our knowledge, this is the first study reporting statistically significant associations between maternal 4,4'-DDT exposure and anthropometric characteristics of the newborns., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Welders are exposed to a number of metallic elements during work. Bioaccessability, that is important for element uptake, has been little studied. This study addresses bioaccessability and uptake of chromium (Cr), molybdenum (Mo), tungsten (W) and vanadium (V) among welders., Methods: Bioaccessability of Cr, Mo, V and W was studied in airborne particulate matter collected by personal sampling of the workroom air among shipyard welders by using the lung lining fluid simulant Hatch solution. Associations between concentrations of Hatch soluble and non-soluble elements (Hatch sol and Hatch non-sol ) and concentrations of the four elements in whole blood, serum, blood cells and urine were studied., Results: Air concentrations of the four elements were low. Only a small fraction of Cr, V and W was Hatch sol , while similar amounts of Mo were Hatch sol and Hatch non-sol . Welders (N=70) had statistically significantly higher concentrations of all four elements in urine and serum when compared to referents (N=74). Highly statistically significant associations were observed between urinary W and Hatch sol W (p<0.001) and serum V and Hatch sol V (p<0.001), in particular when air samples collected the day before collection of biological samples were considered., Conclusions: Associations between Hatch sol elements in air and their biological concentrations were higher than when Hatch non-sol concentrations were considered. Associations were generally higher when air samples collected the day before biological sampling were considered as compared to air samples collected two days before., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

Welders may be exposed to high amounts of manganese (Mn). In this study 63 welders and 65 referents were followed up with neurobehavioral tests approximately 6 years after the initial examination at baseline. The welders were exposed to the geometric mean (GM) Mn concentration of 116μg/m(3) at baseline and 148μg/m(3) at follow-up. Their mean duration of employments as welders was 19.5 years at follow-up. Being exposed as a welder was associated with a decline between baseline and follow-up in the performance on the Static Steadiness Test, Finger Tapping Test and Grooved Pegboard Test. However, the decline was also associated with having high concentrations of carbohydrate deficient transferrin in serum (sCDT), indicating high alcohol consumption. When subjects with sCDT above the upper reference limit of the laboratory (≥1.7%) were excluded from the analyses, no difference in the decline in performance was observed between welders and referents for any of the applied neurobehavioral tests. Three welders had developed bradykinesia at follow-up, as assessed by a substantial decline in their Finger Tapping Test performance. They had also experienced a severe decline in Foot Tapping, Grooved Pegboard and Postural Sway Test scores (while blindfolded), while postural tremor as assessed with the CATSYS Tremor 7.0 was normal. Their neurobehavioral test performance at baseline 6 years previously had been normal., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Iron status was studied in 137 welders exposed to a geometric mean (GM) air concentration of 214 μg/m(3) (range 1-3230) of manganese (Mn), in 137 referents and in 34 former welders. The GM concentrations of S-ferritin were 119 (3-1498), 112 (9-1277) and 98 (12-989) μg/L (p=0.24) in the three groups, respectively. Also the GM concentrations of S-hepcidin were not significantly different between the groups (8.4 μg/L (2.8-117); 6.6 μg/L (1.8-100); 6.5 μg/L (1.2-22)) (p=0.22). Multiple linear regression analysis including all welders and referents showed an increase in the concentration of S-ferritin associated with having serum carbohydrate deficient transferrin (S-CDT) above the upper reference limit of ≥1.7%, indicating high alcohol consumption. Serum C-reactive protein was not associated with exposure as welders, but an association with S-ferritin was shown. The GM S-ferritin concentrations among all welders and referents with S-CDT≥1.7% were 157 μg/L (95% CI 113-218) as compared to 104 μg/L (95% CI 94-116) (p=0.02) in those with S-CDT<1.7%. The GM concentrations of Mn in biological fluids were higher in the welders as compared to the referents, while S-Fe, S-Co and B-Co were statistically significantly lower. This could suggest a competitive inhibition from Mn on the uptake of Fe and Co. Increasing concentrations of S-CDT was associated with higher S-Mn, S-Fe and B-Co in the multiple linear regression analysis. The association between S-CDT and S-Fe remained when all subjects with high S-CDT (≥1.7%) were excluded, suggesting increased uptake of Fe even at lower alcohol consumption., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

Neurobehavioral functions were studied in 137 welders exposed to the geometric mean (GM) air concentration of 214 μg/m(3) (range 1-3230) of manganese (Mn) based on the individual mean from two days of air sampling. Only 22 μg/m(3) (GM) was soluble in the artificial lung fluid Hatch solution. The welders were compared to 137 referents (turner/fitters) recruited from the same plants. The GM concentrations of Mn in whole blood (B-Mn) and urine (U-Mn) were 12.8 μg/L and 0.36 μg/g creatinine versus 8.0 μg/L and 0.07 μg/g creatinine in the referents. Alcohol consumption was assessed by measuring carbohydrate deficient transferrin in serum (sCDT). The welders had poorer performance than the referents on the Grooved Pegboard, Finger Tapping, Simple Reaction Time (SRT) and possibly the Maximum Frequency tests. They also reported more subjective symptoms. Welders with sCDT above the upper reference limit had substantially poorer performances on the Grooved Pegboard test, Finger Tapping test and SRT than welders with sCDT below this level. No effect of high sCDT was observed in the referents, indicating an interaction between high sCDT and exposure to Mn for these tests. Self-reported alcohol consumption had no impact on these neurobehavioral test results. A statistically significant difference in the SRT and Grooved Pegboard test results remained after excluding all subjects with sCDT above the normal level, but the difference in test scores between the groups was smaller. These welders also reported more subjective symptoms than the referents. The results suggest that sCDT should be measured in neurobehavioral studies of occupationally Mn exposed populations for a more precise estimation of high alcohol consumption., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Blood and urine samples for determination of manganese (Mn) and iron (Fe) concentrations were collected in a cross-sectional study of 137 currently exposed welders, 137 referents and 34 former welders. Aerosol samples for measurements of personal air exposure to Mn and Fe were also collected. The aerosol samples were assessed for their solubility using a simulated lung lining fluid (Hatch solution). On average 13.8% of the total Mn mass (range 1-49%; N = 237) was soluble (Hatch sol), while only 1.4% (<0.1-10.0%; N = 237) of the total Fe mass was Hatch sol. The welders had statistically significantly higher geometric mean concentrations of Mn in whole blood (B-Mn 12.8 vs. 8.0 μg L (-1)), serum (S-Mn 1.04 vs. 0.77 μg L(-1)) and urine (U-Mn 0.36 vs. 0.07 μg g (-1) cr.) than the referents. Statistically significant univariate correlations were observed between exposure to Hatch sol Mn in the welding aerosol and B-Mn, S-Mn and U-Mn respectively. Pearson's correlation coefficient between mean Hatch sol Mn of two days preceding the collection of biological samples and U-Mn was 0.46 (p < 0.001). The duration of employment as a welder in years was also associated with B-Mn and S-Mn, but not with U-Mn. Statistically significantly higher U-Mn and B-Mn were observed in welders currently exposed to even less than 12 and 6 μg m (-3) Hatchsol Mn, respectively. When using the 95(th) percentile concentration among the referents as a cut-point, 70.0 and 64.5% of the most highly exposed welders exceeded this level with respect to B-Mn and U-Mn. The concentrations of B-Mn, S-Mn and U-Mn were all highly correlated in the welders, but not in the referents.

Biologic monitoring data in electric welders revealed reliable correlation between manganese concentration in the whole blood and manganese concentrations in the workplace air. The chronic manganese intoxication patients showed reliable lower levels of urinary iron, cobalt and manganese vs. those values in the reference group.

Peculiarities of nervous system functional state in electric welders exposed to manganese compounds. To evaluate nervous system functional state in electric welders exposed to manganese compounds, the authors conducted transverse study with matched pairs. The electric welders' tests for response rate, diadochokinesis and grasping power were not reliable. No changes were found in tremor characteristics and posture steadiness. Bradykinesia appeared to prevail in welders.

Neurobehavioral functions were studied in 96 welders currently exposed to the geometric mean (GM) concentration of 121 microg/m(3) (range 7-2322) manganese (Mn) in welding fume (air-Mn) based on the individual mean from two successive days of sampling. They were compared to 96 age-matched referents. The arithmetic mean (AM) concentration of Mn in whole blood (B-Mn) was 8.6 microg/L versus 6.9 microg/L in the referents. Associations between the Digit Symbol and Finger Tapping test scores and B-Mn and air-Mn, respectively, were observed. The welders exposed to the highest air-Mn concentrations (GM 423 microg/m(3) range 204-2322) had statistically significantly poorer Finger Tapping test score as compared to their age-matched referents. The welders with the highest AM concentration of B-Mn (12.6 microg/L) scored statistically significantly poorer on the Digit Symbol test when compared to the age-matched referents (AM B-Mn 7.5 microg/L). The same neurobehavioral test battery was applied to 27 patients diagnosed, and financially compensated, as having welding related manganism. They were on average 44.9 (range 34-51) years old at the time of diagnosis, which on average was 5.8 years prior to this study. They had worked as welders for 23.1 years on average (range 15-30). The most affected neurobehavioral functions were associated with impaired Finger Tapping speed and Grooved Pegboard performance. The patients had no alterations in hand tremor as assessed by the CATSYS system, while a few subjects had noticeable tremor as assessed by the Static Steadiness test.

In a cross-sectional study, the serum concentrations of inhibin B and prolactin of 96 male current welders were compared with the concentrations measured in 96 age-matched referents. Also, 23 patients who were all former welders diagnosed as having welding-related manganism were studied. The current welders' geometric mean (GM) airborne exposure to manganese (Mn) was 121 microg m(-3) (range 7-2320). The serum concentrations of prolactin adjusted for age and smoking habits (GM 193 mIU l(-1) vs. 166 mIU l(-1); p=0.047) and inhibin B adjusted for alcohol consumption (arithmetic mean (AM) 151 ng l(-1) vs. 123 ng l(-1); p=0.001) were higher in the welders compared with the referents. The whole blood Mn concentration was associated with the serum prolactin concentrations. Tobacco smoking resulted in lower serum prolactin concentrations. The GM serum prolactin concentrations of the patients did not significantly differ from that of the referents, but their AM serum inhibin B concentration was statistically significantly lower. The results may suggest an effect of Mn on the pituitary that is reversible upon cessation of exposure. Lower inhibin B concentrations in the patients could point to a functional impairment of the testicular Sertoli cells, that may be caused by a welding fume component or other factors in their work environment.

In a cross-sectional study, 96 welders were compared with 96 control subjects. Also 27 former welders, all diagnosed as having manganism, were examined. Exposure to welding fumes was determined in the 96 welders, while the concentration of elements in whole blood and urine was determined in all subjects. The geometric mean (GM) concentrations of manganese (Mn) and iron in the workroom air were 97 microg m(-3) (range 3-4620 microg m(-3); n=188) and 894 microg m(-3) (range 106-20 300 microg m(-3); n=188), respectively. Thus the Mn concentration in the workroom air was on average 10.6% (GM) of that of the Fe concentration. No substantial difference was observed in the air Mn concentrations when welding mild steel as compared to welding stainless steel. The arithmetic mean (AM) concentration of Mn in whole blood (B-Mn) was about 25% higher in the welders compared to the controls (8.6 vs. 6.9 microg l(-1); p < 0.001), while the difference in the urinary Mn concentrations did not attain statistical significance. A Pearson's correlation coefficient of 0.31 (p < 0.01) was calculated between B-Mn and Mn in the workroom air that was collected the day before blood sampling. Although the exposure to welding fumes in the patients had ceased on average 5.8 years prior to the study (range 4 years-7 years), their AM B-Mn concentration was still higher than in referents of similar age (8.7 microg l(-1) vs. 7.0 microg l(-1)). However, their urinary concentrations of cobolt, iron and Mn were all statistically significantly lower.

Analysis of X-ray signs in 397 patients suffering from fluorosis revealed degenerative and dystrophic lumbar disorders in 94%, calcified anterior longitudinal ligament in 65%, various changes (epicondylosis, periarthrosis and arthrosis deformans) in 91%. Locomotory disorders appeared systemic, multiple and symmetrical.