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Currently, nanoparticles are widely present in the environment and are being used in various industrial technologies. Nanoparticles affect immune functions, causing different immune responses. The aim of the current study was to evaluate several cytokines, interleukin (IL)-1b, IL-6, IL-8, tumour necrosis factor-a (TNF-α), interferon-γ, adhesive molecule sICAM-1, macrophage inhibitory protein 1a (MIP1a) and secretory immunoglobulin A, in nasal lavage fluid and in the peripheral blood of healthy subjects exposed to workplace nanoparticles. Thirty-six employees from three different environments were examined: 12 from a metalworking company, 12 from a woodworking company and 12 office workers. The nanoparticles in the different workplaces were detected in the air in the immediate vicinity of the employees. The particle number concentration and surface area values were significantly higher in the workplaces of the metal- and woodworking industries, but concentrations of mass were lower (the measurements were performed by an electrical low-pressure impactor ELPI+). Energy dispersive X-ray spectroscopy (EDS, an attachment to a high-resolution SEM) was used to provide elemental analysis or chemical characterization of the dust particles in a low-vacuum field-free mode operating at a potential of 15 kV spot 3.0. The technique used provided quantitative and spatial analyses of the distribution of elements through mapping (two to three parallel measurements) and point analysis (four to five parallel measurements). Samples from the metal industry contained more ultramicroscopic and nanometric particles, e.g. toxic metals such as Zn, Mn and Cr, and fewer microscopic dust particles. The nasal lavage and peripheral blood were taken at the beginning and the end of the working week, when immune indices were measured. Our data showed a statistically significant increased level of the pro-inflammatory cytokine TNF-α in serum in both exposed groups compared with office workers as well as a higher level of TNF-α in workers from the woodworking company compared with the metalworking employees. We found an elevated level of IL-6 in the exposed groups as well as an elevated level of IL-8 in the nasal lavage in woodworking employees after work.

Computer work is characterized by sedentary static workload with low-intensity energy metabolism. The aim of our study was to evaluate the dynamics of skin surface temperature in the hand during prolonged computer mouse work under different ergonomic setups. Digital infrared imaging of the right forearm and wrist was performed during three hours of continuous computer work (measured at the start and every 15 minutes thereafter) in a laboratory with controlled ambient conditions. Four people participated in the study. Three different ergonomic computer mouse setups were tested on three different days (horizontal computer mouse without mouse pad; horizontal computer mouse with mouse pad and padded wrist support; vertical computer mouse without mouse pad). The study revealed a significantly strong negative correlation between the temperature of the dorsal surface of the wrist and time spent working with a computer mouse. Hand skin temperature decreased markedly after one hour of continuous computer mouse work. Vertical computer mouse work preserved more stable and higher temperatures of the wrist (>30 °C), while continuous use of a horizontal mouse for more than two hours caused an extremely low temperature (<28 °C) in distal parts of the hand. The preliminary observational findings indicate the significant effect of the duration and ergonomics of computer mouse work on the development of hand hypothermia.

The outcome of the Chernobyl nuclear power plant (CNPP) accident was that a huge number of people were exposed to ionizing radiation. Previous studies of CNPP clean-up workers from Latvia revealed a high occurrence of age-associated degenerative diseases and cancer in young adults, as well as a high mortality as a result of cardiovascular disorders at age 45-54 years. DNA tandem repeats that cap chromosome ends, known as telomeres, are sensitive to oxidative damage and exposure to ionizing radiation. Telomeres are important in aging processes and carcinogenesis. The aim of this study was to investigate the long-term effect of protracted ionizing radiation exposure on telomere length in CNPP clean-up workers. Relative telomere length (RTL) was measured in peripheral blood leukocytes of 595 CNPP clean-up workers and 236 gender- and age-matched controls using real-time quantitative polymerase chain reaction (q-PCR). Close attention was paid to participation year and tasks performed during the worker's stay in Chernobyl, health status, and RTL differences between subgroups. Telomere shortening was not found in CNPP clean-up workers; on the contrary, their RTL was slightly greater than in controls (P = 0.001). Longer telomeres were found in people who worked during 1986, in those undertaking 'dirty' tasks (digging and deactivation), and in people with cancer. Shorter telomeres appeared frequently in those with cataract, osteoporosis, atherosclerosis, or coronary heart disease. We conclude that the longer telomeres revealed in people more heavily exposed to ionizing radiation probably indicate activation of telomerase as a chromosome healing mechanism following damage, and reflect defects in telomerase regulation that could potentiate carcinogenesis., (© The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.)

Quantitative assay of nitric oxide (NO) and iron (Fe) was carried out by the electron paramagnetic resonance (EPR) method in epidermal derivative (hair) of 45 liquidators of the Chernobyl accident, 30 employees of radiological institutions having contact with radiation, and 50 students of Vladimir State University, most of which were diagnosed with iron deficiency, namely iron deficiency anemia (4 persons) and latent iron deficiency (34 persons). Measurements were performed on a Radiopan EPR-spectrometer. It was found that the method of quantitative EPR-spectroscopy using diethyldithiocarbamate as a trap in vitro could be successfully used to measure NO-radical activity in such a biological substrate as hair. It was found that the intensity of NO-radical signal in the spectrogram depends on the Fe level (not only in the analyzed substrate, but also in the whole organism).

The use of hydrophobic fluorescent probe ABM (benzanthrone derivative) and albumin autofluorescence allowed show conformational alterations in Chernobyl clean-up workers blood plasma. Results obtained in 1996-1997 suggest that acidic expansion of plasma albumin takes place. Latest data (2006-2008) result in splitting of albumin alterations onto two stages - acidic expansion and N-F transition. The N-F transition is accompanied by the blue shift of fluorescence spectra and dehydration of tryptophanyl region of albumin molecule. In 2007 obtained.patterns of ABM spectra had never been previously seen in examined healthy individuals or patients with tuberculosis, multiple sclerosis, rheumatoid arthritis, etc. Patterns of ABM fluorescence spectra are associated with conformational changes of blood plasma albumin. The use of probe ABM and albumin auto-fluorescence allowed show conformational alterations in albumin of Chernobyl clean-up workers blood plasma. It is necessary to note that all investigated parameters significantly differ in observed groups of patients. These findings reinforce our understanding that the blood plasma albumin is a significant biological target of radiation. It may be concluded that fluorescence characteristics are representative of radiation induced albumin alterations and its carrier function., (© Springer Science+Business Media, LLC 2010)

Aims: To establish if there is further evidence for the long-term oxidant stress injury (as reported previously--Kumerova et al. in Biol Trace Elem Res 77:1-12, 2000) in surviving Chernobyl nuclear power plant (NPP) workers from Latvia. The overall objectives of this study have been to establish if there have been long-term systemic changes in the oxidant/antioxidant status of clean-up workers that might reflect adaptation to the progression of oxidative stress injury., Methods: Biochemical analyses of the circulating levels of endogenous oxidants and anti-oxidants were undertaken over two periods (Stage 1 in 1998-1999 and Stage 2 in 2005-2006) at approximately 6-7 years time interval, in order to establish if there have been time-dependent changes in the parameters that may be important for the health of the clean-up workers. The biochemical analyses included (a) plasma levels of the anti-oxidant, selenium, (b) blood and plasma levels of glutathione peroxidase, (c) red blood cell catalase, (d) plasma total oxidant status as lipid peroxides and hydroperoxides, (e) plasma ceruloplasmin, and (f) total blood levels of zinc and copper., Results: The circulating content of lipid peroxides, plasma oxidisability, lipid peroxides, catalase, Zn, and Cu were elevated above normal values at both the stages of this study. Glutathione peroxidase was increased above normal values at Stage 1 but not at Stage 2. The most pronounced changes between Stage 1 and Stage 2 were (a) a reduction by about (1/2) in the content of lipid peroxides and lipid peroxidation, but not in the blood oxidisability and (b) increased plasma selenium. The data show that there may be a partial improvement in the anti-oxidant/oxidant status of the Chernobyl NPP workers over the 7-year period of investigation., Conclusions: The NPP patients may be undergoing progressive reduction in blood oxidants accompanied by adaptation to oxidant stress injury due to the increased anti-oxidant activity measured in their plasma and blood.

The fluorescent probe ABM was used to characterize lymphocyte membranes and blood plasma albumin from cancer patients suffering from colorectal cancer or gastric cancers at Stages II-IV. The aim of these studies was to evaluate the potential utility of measures of ABM fluorescence intensity as a standard tool in the analyses of host immune status and for a clinical interpretation of alterations in albumin per se and lymphocyte functional activity in cancer patients. The fluorescence intensity of ABM in the blood plasma decreased from control values and showed specific differences in each of the differing patients groups; these changes corresponded to cancer stage. The significant decrease in ABM fluorescence in the plasma could be explained, in part, by a diminished binding capacity of the albumin of these patients. The lymphocyte distribution among the subsets of patients also differed. Interestingly, the ABM fluorescence in the cell suspension and blood plasma was also found to correlate with select immunological parameters (CD4(+):CD8(+) ratios, lymphocyte counts, etc.) in the patients. These results obtained here showed that there was a strong agreement between changes in ABM spectral characteristics and both clinical and pathological estimates of disease (i.e., gastrointestinal cancers) severity. Thus, the use of ABM spectroscopy appears to be another tool that might be of some used by clinicians to monitor the course of certain diseases, such as gastrointestinal cancers.

The fluorescent probe ABM (3-aminobenzanthrone derivative) one of the fluorescent probes synthesized in Riga Technical University proved to be an excellent, independent model for studying cell membranes. In our work we have investigated the possibility of using the fluorescent probe ABM for detection of immune state in patients with different pathologies. There is a strong correlation among all studied ABM spectral parameters, immunological characteristics, clinical and laboratory investigations of the all observed patients groups. The obtained results suggest that ABM spectral parameters in cell suspension reflect the alterations of the cellular mechanisms of immunity. Therefore fluorescent method could be used as preliminary screening test in immune diagnostics instead of more expensive, time consuming methods (subset detection, radioisotope method etc.) used as routine in clinics. Spectral parameters of ABM reflect a wide range of interrelated (interdependent) characteristics of cells (physico-chemical state and microviscosity of membrane, proliferating and lipid metabolic activity of cells, distribution of cells among subsets). The observed change of the studied parameters reflects alterations of the cellular mechanisms of immunity which is a main focus for its application as preliminary screening test in immune diagnostics. The fluorescence based method is sensitive, less expensive and time consuming, technically simple and convenient.

The health status of some 6,000 workers from Latvia who went to clean-up the Chernobyl Nuclear Power Plant (CNPP) site following the explosion on 26 April 1986 has been analyzed. The data on these workers have been recorded in the Latvian State Register of Occupational disease patients and people exposed to ionizing radiation due to Chernobyl NPP accident (Latvian State Register) that was established in 1994. From these data, estimates have been made of external ionizing radiation to which these workers were exposed together with observations on the impact of exposure to heavy metals (especially lead and zinc) and radioactive isotopes released during the reactor 'meltdown'. These factors along with psycho-emotional and social-economic stresses account for a marked excess of mortality and morbidity in the group of CNPP accident clean-up workers compared with that of the non-exposed normal Latvian population adjusted for age and sex. The number of diseases or conditions in the CNPP accident clean-up workers has progressively risen from an average of 1.3 in 1986 to 10.9 in 2007. This exceeds for the Latvian population when adjusted for age and sex. The most serious conditions affect the nervous, digestive, respiratory, cardiovascular, endocrine (especially thyroid) and immunological systems. While the morbidity associated with diseases of the respiratory and digestive systems has decreased in recent years that in the other systems is increasing. In recent years, there has been an increased occurrence of cancers affecting the thyroid, prostate and stomach. Clinical and laboratory investigations suggest that surviving CNPP accident clean-up workers exhibit signs of immuno-inflammatory reactions causing premature aging with evidence of autoimmune diseases and immunological deficiencies or abnormalities. It is suggested that the CNPP accident clean-up workers may have a specific syndrome, the 'Chernobyl post-radiation neurosomatic polypathy', due to sustained oxidant stress injury, as a result of exposure to radiation and lead.

ABM (3-aminobenzanthrrone derivative) developed at the Riga Technical University, Riga, Latvia) has been previously shown as a potential probe for determination of the immune state of patients with different pathologies . The fist study (using probe ABM) of peripheral blood mononuclear cells (PBMC) membranes of 97 Chernobyl clean-up workers from Latvia was conducted in 1997. Now we repeatedly examine the same (n = 54) individuals in dynamics. ABM spectral parameters in PBMC suspension, fluorescence anisotropy and blood plasma albumin characteristics were recorded. In 1997 screening showed 5 different patterns of fluorescence spectra, from which in 2007 we obtained only two. These patterns of spectra had never been previously seen in healthy individuals or patients with tuberculosis, multiple sclerosis, rheumatoid arthritis, etc., examined by us. Patterns of ABM fluorescence spectra are associated with membrane anisotropy and conformational changes of blood plasma albumin. We observed that in dynamics 1997-2007 the lipid compartment of the membrane became more fluid while the lipid-protein interface became more rigid. The use of probe ANS and albumin auto-fluorescence allowed show conformational alterations in Chernobyl clean-up workers blood plasma. It is necessary to note that all investigated parameters significantly differ in observed groups of patients. These findings reinforce our understanding that that the cell membrane is a significant biological target of radiation. The role of the membrane in the expression and course of cell damage after radiation exposure must be considered. So ten years dynamic of PBMC membrane characteristics by ABM (spectral shift and anisotropy indexes) in Chernobyl clean-up workers reveal progressive trend toward certain resemblance with those of chronic B-cell lymphoid leukemia.

A fluorescent probe, ABM, aminoderivative of benzanthrone, synthesized in the Department of Organic Chemistry of the Riga Technical University (Latvia), has been successfully used to characterize changes in the structural and functional properties of cell membranes during different pathologies. In the present study the physicochemical properties and the functional activity of the peripheral blood mononuclear cells (lymphocytes-Ly) in patients with rheumatoid arthritis (RA) were studied using the ABM probe. Intensity of the ABM fluorescence in the celi suspension, functional activity of the ly anisotropy of the membranes differ patients with different titres of rheumatoid factor in blood. Patients with seropositive RA had decreased proliferative activity and lower number of iy in blood plasma indicating greater alterations of the immunoregulating processes in these patients as compared to patients with seronegative RA. In the latter the Ly deficiency is compensated to some extent by increased proliferation activity of these cells. The ABM fluorescence intensity correlated not only with membrane anisotropy (r = 0.97, but also with the proliferation activity of the Ly (r = 0.98). The above parameters correlated with the clinical manifestations of the disease. The results indicate that the fluorescent probe ABM is useful for screening the physicochemical status of Ly membranes and the proliferation activity of these cells in RA patients.

Between 1986 and 1991 approximately 6500 Latvian inhabitants were recruited for clean-up work at the Chernobyl nuclear power plant. Their absorbed doses are usually unknown, because less than half of them had their external exposure officially documented. Clinical investigations show a high morbidity rate for these clean-up workers when compared with that of the general population. In order to understand the causes of their diseases and the impact of ionising radiation, electron spin resonance (ESR) has been used to measure the absorbed doses in human tooth enamel. The doses estimated by ESR were between two and three times higher than previously documented and are in accord with the results of immunological and biological tests. The results may be explained by considering the effects of irradiation caused by long-lived incorporated radionuclides.

Epidemiologic studies on the health effects of the Chernobyl disaster have focused largely on physical health, whereas the psychological consequences have received little attention. The authors have assessed the associations of various exposure variables with mental and psychosomatic distress in a sample of 1412 Latvian liquidators drawn from the State Latvian Chernobyl Clean-up Workers Registry. The outcome was a mixed mental-psychosomatic disorder occurring during 1986 to 1995. Comparisons among subgroups of the cohort classified according to exposure type or level were based on the proportional hazards model. Length of work (> or = 28 days) in a 10-km radius from the reactor (relative risk [RR] = 1.39, 95% confidence interval [CI] 1.14-1.70), work (> 1 time) on the damaged reactor roof (RR = 1.46, 95% CI 1.02-2.09), forest work (RR = 1.41, 95% CI 1.19-1.68), fresh fruit consumption (> or = 1 time/day) (RR = 1.72, 95% CI 1.12-2.65) are risk factors for mixed mental-psychosomatic disorder. Construction of the sarcophagus (RR = 1.82, 95% CI 0.89-3.72) is also associated with this outcome, although nonsignificantly. Distinguishing stress-related from radiation-induced effects in this data set was difficult and these findings should provide a basis for later hypothesis testing in other cohorts.