Assessment of selected B cells populations in the workers of X-ray departments

Objectives: Workers of X-ray departments are occupationally exposed to long-term low levels of ionizing radiation (LLIR), which may affect their humoral immunity. The aim of the study was to assess the influence of LLIR on the number and proportion of B cells (CD19+), B1 cells (CD5+CD19+) and memory B cells (CD27+CD19+) in peripheral blood of such workers. Materials and Methods: In the study group of 47 X-ray departments workers and the control group consisting of 38 persons, the number and percentage of CD19+, CD5+CD19+, CD27+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were assessed using flow cytometry. Additionally, the study group was divided into 2 groups by the length of employment below and over 15 years and analysis adjusted for age and smoking habit was performed. Results: The total number of CD19+ cells showed significant increase in the group of workers in comparison with the persons from the control group, whereas the percentage of CD5+CD19+ cells as well as CD27+CD19+/CD19+ and CD5+CD19+/CD19+ cell ratios were lower. Percentage, number of CD5+CD19+ cells and CD5+CD19+/CD19+ cell ratio were significantly lower in the workers with length of employment longer than 15 years in comparison with those employed below 15 years. Moreover, we found positive associations between the number of CD19+ cells and employment as well as smoking habit, whereas the number of CD5+CD19+ cells was positively associated with cigarette smoking alone. Percentage of CD5+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were negatively correlated with employment. Conclusions: The study suggests association between the suppressive influence of low level ionizing radiation on circulating in peripheral blood, especially of B1 cells as well as of memory B cells, in workers of X-ray units, which is adverse in relation to microbiological threat

Comparative studies of residual stress evaluated with Barkhausen effect and trepanation methods in welded joints after thermal and mechanical stress release

Celem pracy było porównanie stanu naprężenia resztkowego w złączach spawanych wyznaczonego metodą nieniszczącą, która bazowała na pomiarze natężenia efektu Barkhausena (metoda EB) oraz metodą niszczącą, określaną jako metoda trepanacyjna. Obiektem badania były trzy modelowe doczołowe złącza spawane wykonane ze stali S235, oznaczone jako P1, P2 i P3. Próbka P2 została odprężona cieplnie, a próbka P3 była odprężona mechanicznie poprzez naprężanie statyczne do granicy plastyczności. Stan naprężenia wyznaczono metodą EB w szeregu punktów na obu powierzchniach próbek. Badania trepanacyjne metodą Gunnerta pozwoliły wyznaczyć odkształcenia względne dla szeregu wąskich pasków wyciętych w części centralnej złącza równolegle do osi spoiny. Te odkształcenia przeliczono na poziomy naprężenia resztkowego w kierunku osi spoiny. Wartości te zostały zestawione z wartościami składowej stycznej naprężenia wyznaczonego metodą EB dla tej części spoiny. Wykazano, iż odprężanie cieplne praktycznie usuwa naprężenie spawalnicze, a odprężanie mechaniczne zmniejsza to naprężenie znacząco. Wyniki badania obiema metodami okazały się być zgodne jakościowo i także ilościowo – po uwzględnieniu ujawnionego metodą EB efektu wygięcia płyt. To świadczy o skuteczności i użyteczności metody EB dla oceny stanu naprężenia w elementach stalowych.The aim of the study was to compare the residual stress in welded joints determined by the non-destructive method, which was based on the Barkhausen effect intensity measurement (EB method), and the destructive method, defined as the trepanation method. Three model butt welds made of S235 steel, marked as P1, P2 and P3, were subjected to the test, P2 was heat annealed and P3 was mechanically annealed by static stress up to yield strength. The stress was determined by EB at a number of points on both faces of the specimens. The trepanation tests by Gunnert allowed to determine the relative deformations for a series of narrow strips cut in the central part of the joint parallel to the weld axis. These deformations have been converted to residual stress levels in the direction of the weld axis. These values were compared with the values of the tangential stress component determined by the EB method for this part of the weld. It has been shown that thermal annealing practically removes welding stress and mechanical annealing significantly reduces this stress. The results of both methods proved to be consistent both qualitatively and quantitatively - after taking into account the bending effect of the panels revealed by the EB method. This demonstrates the effectiveness and usefulness of the EB method in assessing stress in steel elements

Assessment of selected B cells populations in the workers of X-ray departments

Objectives: Workers of X-ray departments are occupationally exposed to long-term low levels of ionizing radiation (LLIR), which may affect their humoral immunity. The aim of the study was to assess the influence of LLIR on the number and proportion of B cells (CD19+), B1 cells (CD5+CD19+) and memory B cells (CD27+CD19+) in peripheral blood of such workers. Materials and Methods: In the study group of 47 X-ray departments workers and the control group consisting of 38 persons, the number and percentage of CD19+, CD5+CD19+, CD27+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were assessed using flow cytometry. Additionally, the study group was divided into 2 groups by the length of employment below and over 15 years and analysis adjusted for age and smoking habit was performed. Results: The total number of CD19+ cells showed significant increase in the group of workers in comparison with the persons from the control group, whereas the percentage of CD5+CD19+ cells as well as CD27+CD19+/CD19+ and CD5+CD19+/CD19+ cell ratios were lower. Percentage, number of CD5+CD19+ cells and CD5+CD19+/CD19+ cell ratio were significantly lower in the workers with length of employment longer than 15 years in comparison with those employed below 15 years. Moreover, we found positive associations between the number of CD19+ cells and employment as well as smoking habit, whereas the number of CD5+CD19+ cells was positively associated with cigarette smoking alone. Percentage of CD5+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were negatively correlated with employment. Conclusions: The study suggests association between the suppressive influence of low level ionizing radiation on circulating in peripheral blood, especially of B1 cells as well as of memory B cells, in workers of X-ray units, which is adverse in relation to microbiological threat

Evaluation of selected population of lymphocytes and concentrations of immunoglobulins in workers of interventional cardiology wards using low doses of ionizing radiation in cardiovascular procedures

INTRODUCE The aim of the study was to determinate the effect of low X-ray doses on the percentage and number of peripheral blood lymphocytes T (CD3+), T helper (CD4+), T cytotoxic (CD8+), lymphocytes B (CD19+), activated T lymphocytes (CD3+CD25+) and activated T helper lymphocytes (CD4+CD25+) as well as serum immunoglobulins (IgM, IgG and IgA) concentration in workers of an interventional cardiology ward. MATERIAL AND METHODS The study was performed among a group of 40 workers (28 women and 12 men) and a control group of 35 persons (25 women and 10 men). Flow cytometry was used for the analysis of lymphocytes and the turbidimetric method for assessing serum immunoglobulin concentrations. RESULTS The study showed a decreased percentage and number of CD3+CD25+ and CD4+CD25+ cells as well as IgG concentration in interventional cardiology ward staff in comparison to the control group. A negative correlation between the length of employment and percentage of CD3+CD25+ was found. CONCLUSION The study indicates suppressive impact low doses of ionizing radiation on activated T cells, activated T helper cells as well as IgG production that is adverse in relation to the existing risk of infections caused by different microorganisms.WSTĘP Celem pracy była ocena oddziaływania niskich dawek promieniowania jonizującego na odsetek i liczbę limfocytów T (CD3+), limfocytów T pomocniczych (CD4+), limfocytów T cytotoksyczych (CD8+), limfocytów B (CD19+), aktywowanych limfocytów T (CD3+CD25+) i aktywowanych limfocytów T pomocniczych (CD4+CD25+) oraz stężeń immunoglobulin IgM, IgG i IgA u pracow-ników oddziału kardiologii interwencyjnej. MATERIAŁ I METODY Badanie przeprowadzono w grupie 40 zatrudnionych (28 kobiet i 12 mężczyzn) oraz w grupie kontrolnej 35 osób (25 kobiet i 10 mężczyzn). Badania limfocytów krwi obwodowej przeprowadzono z wykorzystaniem cytometrii przepływowej, a stężenia immunoglobulin w surowicy oznaczono metodą turbidymetryczną. WYNIKI W badanej grupie pracowników – w porównaniu z grupą kontrolną – wykazano znamienne obniżenie liczby i odsetka limfocytów CD3+CD25+ i CD4+CD25+ oraz stężeń immunoglobuliny IgG. Wykazano także istnienie negatywnej korelacji między okresem zatrudnienia badanych pracowników a odsetkiem limfocytów CD3+CD25+. WNIOSEK Badanie wskazuje na supresyjne oddziaływanie niskich dawek promieniowania jonizującego na aktywowane limfocyty T, aktywowane limfocyty T pomocnicze i produkcję IgG, co nie jest korzystne w odniesieniu do istniejącego ryzyka zakażeń drobnoustrojami