Silica is the second most common element after oxygen, and therefore, exposures to crystalline silica dust occur in a large variety of occupations such as metal foundries, constructions, and ceramic, quarry, and pottery industries. Since crystalline silica exposure has been linked with silicosis, lung cancer, and other pulmonary diseases, adverse effect attributed to this element has be a cause for concern worldwide. Silica dust exposure in workers is still considered to be important health problem especially in developing countries. The aim of the study was to investigate the effects of occupational silica exposure on oxidative stress parameters including the activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), and levels of total glutathione (GSH) and thiobarbituric acid reactive substance (TBARS) as well as immune system parameters such as interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, and IL-10 and tumor necrosis factor (TNF)-α in Turkish ceramic workers. In this study, nearly 50% of Turkish ceramic workers were diagnosed with silicosis. Eighty-four percent of these silicotic workers were found to present with profusion category 1 silicosis, whereas controls (n = 81) all displayed normal chest radiographs. Data demonstrated a significant decrease in levels of GSH and activities of CAT, SOD, and GPx, but a significant increase in MDA levels and activity of GR in all workers. Further, workers possessed significantly higher levels of IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-10, and TNF-α. These observations suggest that ceramic workers may have impaired antioxidant/oxidant status and activated immune system indicative of inflammatory responses.

In this study, we aimed to investigate disulfide/thiol homeostasis in trichloroethylene (TCE) exposure. The study was carried out in 30 nonsmoker TCE-exposed workers with a variety of occupations. Additionally, 30 healthy nonsmoker volunteers were recruited as the control group. TCE exposure was determined by measuring urinary trichloroacetic acid (TCA) concentration. Median urinary TCA levels of exposed workers (20.5 mg/L) were significantly higher than control subjects (5 mg/L). Thiol and disulfide concentrations were determined using a novel automated method. Disulfide/thiol ratio was significantly higher in the exposed group ( p < 0.001). Thiol/disulfide homeostasis was found to be disturbed in TCE-exposed workers. We predict that in TCE-exposed workers this disturbance can be a therapeutic target, and the efficiency of the treatment can easily be monitored by the novel method we used.

Introduction: Psoriasis is a common, inflammatory skin disease of which etiopathogenesis is still not explained clearly, however in which trace elements and oxidative stress are considered to play a role. Aim: To evaluate the serum trace element and oxidative stress levels in patients diagnosed with psoriasis. Material and methods: A total of 87 psoriasis patients and 60 healthy subjects were included in the study. Serum sodium (Na), potassium (K), calcium (Ca), phosphorus (P), magnesium (Mg), iron (Fe), selenium (Se), zinc (Zn), copper (Cu) levels, oxidative stress parameters, ischemia-modified albumin (IMA), catalase (CAT), myeloperoxidase (MPO) and ferroxidase (FOX) activity and an inflammatory marker, C-reactive protein (CRP), were examined in all participants. Results: IMA, IMA/Albumin (IMA/Alb), CAT, Cu, FOX and CRP levels were found to be significantly higher; Se, Zn and albumin levels were significantly lower in the patient group as compared to the control group. No significant difference was found between groups with regard to Na, K, Ca, P, Mg, Fe and MPO levels. Conclusions: Some trace element levels and oxidant-antioxidant balance were changed in psoriasis patients.

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Objectives The aim of this study was to evaluate 2 new oxidative stress markers, thiol/disulfide homeostasis status and the asymmetric dimethylarginine (ADMA) level, in children with acute appendicitis (AA) and to evaluate their diagnostic utility. Methods This case-control study included 45 patients with AA and 35 healthy children. Age, sex, white blood cell count, neutrophil-to-lymphocyte ratio, high-sensitivity C-reactive protein (hs-CRP) level, ultrasonographic findings, thiol/disulfide homeostasis parameters (native and total thiol levels, native thiol/total thiol ratios [antioxidant parameters], and disulfide, disulfide/native thiol, and disulfide/total thiol ratios [oxidant parameters]), and the ADMA level were compared between the 2 groups. Results The native and total thiol levels, and the native thiol/total thiol ratio, were significantly lower, and the disulfide level and disulfide/native thiol and disulfide/total thiol ratios significantly higher, in the AA compared with the control group (all P < 0.001). The ADMA level was significantly higher in a perforated versus nonperforated subgroup of AA patients, but the thiol/disulfide homeostasis parameters did not differ significantly between the two subgroups. In addition, the hs-CRP level and appendiceal wall thickness were higher in the perforated subgroup. The thiol/disulfide antioxidant parameters and ADMA level correlated negatively with the white blood cell count, the neutrophil-to-lymphocyte ratio, and the hs-CRP level, in the AA group, but correlated positively with oxidant parameters. The sensitivity and specificity of the disulfide/native thiol and disulfide/total thiol ratios were high when used to diagnose AA, whereas the sensitivity of the ADMA level was high when used to diagnose perforated appendicitis. Conclusions Thiol/disulfide homeostasis and the ADMA level, together with certain other parameters, may be useful biomarkers of AA in children.

Iron overload in hereditary hemochromatosis and hematologic malignancy has unfavorable effects on morbidity. Herein, 53 children (age 108.4±58.3 mo, 25 girls and 28 boys) with acute myeloblastic and lymphoblastic leukemia, who received 4 different chemotherapy protocols, were evaluated for iron overload throughout chemotherapy. Iron overload arose: (1) before chemotherapy, which was dependent on neither chemotherapy nor packed red blood cell transfusions and (2) after chemotherapy, which was dependent on the duration and nature of chemotherapy and partially on transfusion of packed red blood cells. Iron overload was documented in 75% of patients with a ferritin level >1000 ng/mL, by liver and heart magnetic resonance imaging, and they were administered iron-chelation therapy with success. Three of 10 radiologically iron-overloaded patients were heterozygous for H63D mutation. Aminolevulinic acid and porphobilinogen levels were normal. Light microscopic examination of the bone marrow revealed increased iron granules in erythroblasts, platelets, and megakaryocytes, iron-laden macrophages, free iron in the matrix, dyshematopoiesis, and apoptotic cells. Electron microscopic examination revealed iron-laden secondary lysosomes and autolysosomes in normoblasts and iron-laden primary granules in promyelocytes, irrelevant to the ferritin level, implying autophagia due to chemotherapy as a source of the excess iron. We think that iron overload, which is an important complication of acute leukemia, should be evaluated separately from "transfusion overload," and the management principles specific to leukemia should be implemented.

One of the major complications of arsenic on human health is hypertension. Arsenic-related hypertension and negative effects of arsenic on arterial system such as oxidative stress and vasoconstriction/vasorelaxation imbalance may lead to impair aortic elasticity. The aim of this study was to evaluate the effects of arsenic on aortic elasticity parameters including aortic strain and distensibility. One hundred twelve (112) workers were occupationally exposed to arsenic and 60 healthy control subjects were enroled. All patients underwent transthoracic echocardiography for detecting aortic strain and aortic distensibility. There were no differences in baseline demographic and echocardiographic characteristics between the groups. Aortic strain (10.3±3.9 vs 12.1±2.7%, P=0.001) and aortic distensibility (0.45±0.17 vs 0.54±0.15 cm per dyn, P=0.001) were decreased in arsenic-exposure group compared with controls. Urinary arsenic level was found to be negatively and significantly correlated with aortic strain (r=-0.306, P=0.001) and aortic distensibility (r=-0.259, P=0.006). Duration of arsenic exposure was also found to be negatively and significantly correlated with aortic strain (r=-0.386, P<0.001) and aortic distensibility (r=-0.333, P<0.001). This study suggests that arsenic exposure is related to impairment of aortic elasticity parameters even in subjects without overt cardiovascular disease.

Background:Oxidative stress is implicated as one of the main molecular mechanism underlying silicosis.Aims:In this study, our aim was to asses the redox status in occupationally silica-exposed workers, by evaluating the dynamic thiol-disulphide homeostasis.Study Design:Case-control study.Methods:Thirty-six male workers occupationally exposed to silica particles and 30 healthy volunteers, working as office workers were included to the study. Posteroanterior chest radiographs and pulmonary function tests of both groups were evaluated. Also serum thiol disulphide levels were measured using the spectrophotometric method described by Erel and Neşelioğlu.Results:Among the 36 workers that underwent pulmonary function tests 6 (17%) had obstructive, 7 (19%) had restrictive, 6 (17%) had obstructive and restrictive signs whereas 17 (47%) had no signs. The mean PFTs results of silica-exposed workers were significantly lower than control subjects. The serum disulphide levels of silica-exposed workers were significantly higher than control subjects (23.84±5.89 μmol/L and 21.18±3.44 μmol/L, respectively p=0.02).Conclusion:The serum disulphide levels, a biomarker of oxidative stress, are found to be higher in silica-exposed workers.