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Relation between occupational exposure to lead, cadmium, arsenic and concentration of cystatin C.

UNLABELLED Lead, cadmium and arsenic represent well recognized toxic agents which in a specific manner disturb function of cardiovascular system. Cystatin C has been accepted to be a significant prognostic factor for cardiovascular diseases. The study aimed at defining relationship between occupational exposure to lead, cadmium and arsenic on one hand and concentration of cystatin C on the other. The studies were performed on 282 men occupationally exposed to lead, cadmium and arsenic. Among the tested individuals several groups of persons were distinguished: exposed exclusively to lead (Pb group), cadmium (Cd group), arsenic (As group), to lead and cadmium (Pb/Cd group), to lead and arsenic (Pb/As group) or to cadmium and arsenic (Cd/As group). In all the individuals serum concentration of cystatin C was estimated. Concentration of cystatin C was found to be significantly higher in Pb group than in Cd and As groups, also in Pb/Cd group higher than in Cd group and in Pb/As group than in As group. Positive linear correlations were established between Pb concentration in blood (Pb-B) and serum concentration of cystatin C (r=0.59; p<0.05) as well as between urinary concentration of As (As-U) and serum concentration of cystatin C (r=0.41; p<0.05). Regression analysis demonstrated that higher blood level of lead, higher urinary level of arsenic, more advanced age and higher body mass index represented independent risk factors of an increased serum concentration of cystatin C in the group of persons exposed to lead, cadmium and arsenic. CONCLUSIONS Higher blood level of lead and higher urinary level of arsenic represented independent risk factors of an increased serum concentration of cystatin C in the group of persons occupationally exposed to lead, cadmium and arsenic. Concentration of lead in blood was significantly influencing serum concentration of cystatin C. The highest mean serum concentration of cystatin C was detected in the group of foundry workers exposed simultaneously to lead and arsenic.

The relationship between occupational exposure to lead and manifestation of cardiovascular complications in persons with arterial hypertension

The chronic exposure to lead represents a risk factor of arterial hypertension development. Ambulatory blood pressure monitoring is the most prognostically reliable method of measuring of arterial blood pressure. The study is aimed at evaluating the relationship between occupational exposure to lead and manifestation of cardiovascular complications in patients with arterial hypertension. The studies included 73 men (mean age, 54.26±8.17 years) with arterial hypertension, treated with hypotensive drugs: group I-persons occupationally exposed to lead (n=35) and group II-individuals not exposed to lead (n=38). An analysis of results obtained during ambulatory blood pressure monitoring disclosed significantly higher values of mean systolic blood pressure, mean blood pressure, pulse pressure, and variability of systolic blood pressure in the group of hypertensive patients occupationally exposed to lead as compared to patients with arterial hypertension but not exposed to lead. The logistic regression showed that a more advanced age, higher concentration of blood zinc protoporphyrin, and a higher mean value of pulse pressure represented independent risk factors of left ventricular hypertrophy in the group of persons with arterial hypertension and chronically exposed to lead (OR(age)=1.11; OR(ZnPP)=1.32; OR(PP)=1,43; p<0.05). In view of the above data demonstration that occupational exposure to lead represents an independent risk factor of increased pulse pressure may be of key importance in the process of shaping general social awareness as to harmful effects of lead compounds on human health.

The dependence between urinary mercury concentration and carotid arterial intima-media thickness in workers occupationally exposed to mercury vapour

OBJECTIVES Mechanisms of the mercury effect on arterial vessel walls include increased free radicals generation, decreased nitric oxide synthesis and increased reactivity to vasoconstrictors, leading to accelerated development of atherosclerosis and arterial hypertension. The aim of this study was to evaluate the correlation between urinary mercury (Hg-U) concentration and carotid intima-media thickness (IMT) or intraventricular septum diastolic diameter (IVSDD) to find the best markers of mercury cardiovascular toxicity. MATERIALS AND METHODS The study included 154 workers of a chemical factory using mercury in chlorine production. Urinary mercury concentration was determined by atomic absorption spectrophotometry. Serum lipids were assessed by routine methods using enzymatic assay. Serum total antioxidant status (TAS) was determined by colorimetry. Measurements of IMT and IVSDD were made by ultrasound imaging using MEDISON SA 9900 PRIME system. RESULTS The mean Hg-U concentration was 1.9+/-2.7 microg/g creatinine in women (n = 29) and 5.6+/-12.2 microg/g creatinine in men (n = 125). In the group of non-smokers (n = 102) there was a positive linear correlation between Hg-U concentration and IMT (r = 0.1728; p < 0.05) and a negative dependence between high density cholesterol (HDL-C) and IMT (r = -0.2109; p < 0.01). The negative linear correlation between serum total antioxidant status (TAS) and carotid IMT (r = -0.2142; p < 0.05), and the positive correlation between HDL-C and TAS (r = 0.1953; p < 0.05) were shown to be valid for the total studied group. Serum lipids in women were normal, but in men the mean triglyceride level was higher than normal. CONCLUSIONS The occupational exposure to mercury vapour remains in a relationship with early, asymptomatic carotid atherosclerosis. The dependence between urinary mercury elimination and carotid intima-media thickness is evidenced in non-smoking workers. Defensive anti-atherosclerotic mechanisms in these workers are strongly related with HDL. In smokers, these protective mechanisms are disturbed.

Ambulatory blood pressure monitoring and structural changes in carotid arteries in normotensive workers occupationally exposed to lead

Occupational exposure to lead may cause an increase in blood pressure. The aim of the study was to estimate the effect of occupational exposure to lead on selected parameters of ambulatory blood pressure monitoring (ABPM) and structural changes in carotid arteries. The study included 33 normotensive men occupationally exposed to lead and 39 unexposed men employed in administration of the foundry. All of the men underwent 24-hour ambulatory blood pressure monitoring and high-resolution B-mode ultrasonography to determine intima-media thickness (IMT). The group of men occupationally exposed to lead manifested significantly higher mean systolic blood pressure (MSBP), mean diastolic blood pressure (MDBP), mean blood pressure (MBP), pulse pressure (PP), variability of diastolic blood pressure (VDBP), and IMT than the unexposed group. The studied groups did not differ in mean values of variability of systolic blood pressure (VSBP). As compared to the unexposed group, in men exposed to lead, atherosclerotic plaques were significantly more common. In the group of persons exposed to lead the Pearson’s correlation coefficient analysis revealed significant linear positive correlations between MSBP and IMT, between lead level and the number of atherosclerotic plaques, and between lead level and PP. Multivariate stepwise regression analysis demonstrated that higher lead level in blood and higher triglyceride concentration in blood represent independent risk factors of an increased pulse pressure in the group of individuals occupationally exposed to lead. Occupational exposure to lead can be associated with increased blood pressure and accelerated progression of atherosclerosis.

Electrocardiographic evaluation in patients with systemic scleroderma and without clinically evident heart disease.

Background: In patients with systemic scleroderma (SSc), clinically evident cardiac involvement is recognized to be a poor prognostic factor. The aim of the study was to evaluate electrocardiographic changes, parameters of heart rate variability (HRV), and heart rate turbulence (HRT) in patients with SSc without evident symptoms of heart disease.

Renal artery stenosis in patients with resistant hypertension.

The aim of the study was to assess the significance of renal translesional pressure gradients in predicting improvement in resistant hypertension after stenting for moderate renal artery stenosis (RAS). In 37 patients with RAS and resistant hypertension subjected to renal stenting, translesional pressure gradients both at rest and hyperemic were measured using a pressure guidewire. Twenty-four-hour ambulatory blood pressure measurements were performed in all patients on admission and 3 months after the intervention. Angioplasty was successful in all patients, with reduction of artery diameter stenosis from 60 ± 12% to 10 ± 6% (p <0.0001). At 3 months, with maintained hypotensive agents (4.0 ± 1.4 vs 4.0 ± 1.6), significant reductions in systolic blood pressure (SBP) and diastolic blood pressure were noted (-5 and -2 mm Hg, respectively). In multivariate analysis, the mean baseline gradient (MBG) was the only independent predictor of improvement in SBP (regression coefficient 0.292; standard error 0.11; p value 0.014). In the receiver operating characteristic curve analysis, MBG had a larger area under the curve than other parameters, and the MBG >22 mm Hg had the highest sensitivity, specificity, and accuracy (50%, 95%, and 0.74%, respectively) in predicting hypertension improvement after stenting. In patients with MBG >22 mm Hg, SBP decreased by 12 versus 3 mm Hg (p <0.01) in patients with MBG ≤22 mm Hg, whereas diastolic blood pressure in both groups decreased by 3 versus 1 mm Hg, respectively (NS). In conclusion, MBG value of >22 mm Hg provides the highest accuracy in predicting hypertension improvement after stenting for moderate RAS in patients with resistant hypertension.

Usefulness of Intravascular Low-Power Laser Illumination in Preventing Restenosis After Percutaneous Coronary Intervention

Despite the several years of studies, no factor that could reduce the restenosis rate without significant limitations has been introduced. The aim of the present study was to evaluate the influence of low-power 808-nm laser illumination of coronary vessels after percutaneous angioplasty in preventing restenosis. The procedure of laser intravascular illumination was performed on 52 patients (laser group), and another 49 patients formed the control group. All patients were monitored for major adverse cardiac events (MACE) at the 6- and 12-month follow-up points. The MACE rate after 6 and 12 months was 7.7% in the laser group at both points. The MACE rate was 14.3% and 18.5% at 6 and 12 months of follow-up in the control group, respectively (p = NS). Follow-up coronary angiography was performed after 6 months. The difference in the restenosis rate was insignificant (15.0% vs 32.4%); however, significant differences were observed in the minimal lumen diameter (2.18 ± 0.70 vs 1.76 ± 0.74 mm; p < 0.05), late lumen loss (0.53 ± 0.68 vs 0.76 ± 0.76 mm; p < 0.01), and the late lumen loss index (0.28 ± 0.39 vs 0.46 ± 0.43; p < 0.005) in favor of the laser group. In conclusion, the new therapy seemed effective and safe. Marked differences between late loss, late loss index, and minimal lumen diameter were observed. The late lumen loss in the laser group was only slightly greater than that in studies of drug-eluting stents, and MACE rate remained within very comparable ranges. This suggests that intravascular laser illumination could bring advantages comparable to those of drug-eluting stents without the risk of late thrombosis.

Electrocardiographic Changes in Workers Occupationally Exposed to Lead

Background: The significance of heavy metals in pathogenesis of the circulatory system diseases remains unresolved. The aim of the study was to evaluate electrocardiographic changes in workers occupationally exposed to lead without clinical presentation of cardiac involvement.

Plasma asymmetric dimethylarginine predicts restenosis after coronary angioplasty

Introduction Asymmetric dimethylarginine (ADMA) is an endogenous competitive inhibitor of endothelial nitric oxide synthase. Asymmetric dimethylarginine may influence the process of restenosis after coronary angioplasty. The aim of the study was to determine if initial plasma ADMA level could predict restenosis after coronary angioplasty and stenting. Material and methods The study group consisted of 60 consecutive patients (10 women and 50 men, average age 58.9 ±10.4 years old), who underwent percutaneous coronary angioplasty with bare metal stenting for stable coronary artery disease. All patients underwent follow-up coronary angiography after a 6-month period. Patients were divided into two groups, one with restenosis (n = 22), and the other one without restenosis (n = 38). In addition to measuring acknowledged restenosis risk factors, plasma ADMA level was measured before initial angiography. Results Asymmetric dimethylarginine plasma level was significantly higher in the group with restenosis than in the group without restenosis (1.94 ±0.94 µmol/l vs. 0.96 ±0.67 µmol/l; p < 0.05). L-arginine/ADMA ratio was also decreased in the group with restenosis, when compared with the group without restenosis (p < 0.05). Multivariate logistic regression revealed that independent restenosis risk factors were characterised by an initially high ADMA level (p < 0.01), advanced age (p < 0.05) and low level of HDL cholesterol (p < 0.05). Conclusions Pre-procedural elevated plasma ADMA level increases the risk of restenosis in patients who underwent coronary angioplasty and stenting with bare metal stents.

The expression of Toll-like receptors in patients with acute myeloid leukemia treated with induction chemotherapy

Toll-like receptors play an important role in the host defense against microorganisms. TLRs are mainly expressed in human immune-related cells, such as monocytes, neutrophils, macrophages, dendritic cells, T cells, B cells and NK cells. The expression or up-regulation of TLRs has been demonstrated in some tumors and tumor cell lines but the role of TLRs in pathogenesis and development of acute leukemias remains unclear. The aim of this study was to evaluate the expression of TLR2, TLR4 and TLR9 and their significance as prognostic factors in patients with acute leukemias treated with induction chemotherapy. 103 patients with newly diagnosed acute myeloid leukemia (AML) were evaluated (47 females and 56 males). The median age of patients was 51 years. Using quantitative reverse transcriptase PCR, the mRNA expression of genes TLR2, TLR4 and TLR9 was measured. The mRNA expression of TLR2 and TLR4 was significantly higher in patients with NR than in patients with CR and CRi. We especially observed that mRNA expression of TLR2 and TLR4 was significantly higher in patients with myelomonocytic and monoblastic acute leukemia than in patients with other types of AML. The mRNA expression of TLR2 and TLR4 was higher in AML patients than in healthy individuals, although there was no statistically significant difference. Patients with higher mRNA expression of TLR2 and TLR4 had significantly shorter OS than patients with lower mRNA expression of TLR2 and TLR4. Multivariate analysis showed that mRNA expression of TLR2 and the age of patients were independent factors associated with treatment response. Our results suggest that TLRs could be an independent prognostic factor for response rate after induction therapy in patients with acute myeloid leukemias.