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Abstract

Background Coronavirus disease 2019 (COVID-19) is a systemic disease affecting multiple organs. Furthermore, viral infection depletes several trace elements and promotes complex biochemical reactions in the body. Smoking has been linked to the incidence of COVID-19 and associated mortality, and it may impact clinical effects, viral and bacterial conversion, and treatment outcomes. Objectives To study the relationship between severe acute respiratory syndrome coronavirus type 2 and the elemental concentrations of selenium (Se) and mercury (Hg) in biological samples from smokers and nonsmokers infected with the virus and in healthy individuals. Method We evaluated changes in the concentrations of essential (Se) and toxic (Hg) elements in biological samples (blood, nasal fluid, saliva, sputum, serum, and scalp hair) collected from male smokers and nonsmokers (aged 29–59 years) infected with COVID-19 and from healthy men in the same age group. The patients lived in different cities in Sindh Province, Pakistan. The Se and Hg concentrations were determined using atomic absorption spectrophotometry. Results Se concentrations in all types of biological samples from smokers and nonsmokers with COVID-19 were lower than those of healthy smokers and nonsmokers. Hg concentrations were elevated in both smokers and nonsmokers with COVID-19. Conclusions In the current study, persons infected with COVID-19 had higher concentrations of toxic Hg, which could cause physiological disorders, and low concentrations of essential Se, which can also cause weakness. COVID-19 infection showed positive correlations with levels of mercury and selenium. Thus, additional clinical and experimental investigations are essential.

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SARS-CoV-2 infections underlie the current coronavirus disease (COVID-19) pandemic and are causative for a high death toll particularly among elderly subjects and those with comorbidities. Selenium (Se) is an essential trace element of high importance for human health and particularly for a well-balanced immune response. The mortality risk from a severe disease like sepsis or polytrauma is inversely related to Se status. We hypothesized that this relation also applies to COVID-19. Serum samples (n = 166) from COVID-19 patients (n = 33) were collected consecutively and analyzed for total Se by X-ray fluorescence and selenoprotein P (SELENOP) by a validated ELISA. Both biomarkers showed the expected strong correlation (r = 0.7758, p < 0.001), pointing to an insufficient Se availability for optimal selenoprotein expression. In comparison with reference data from a European cross-sectional analysis (EPIC, n = 1915), the patients showed a pronounced deficit in total serum Se (mean ± SD, 50.8 ± 15.7 vs. 84.4 ± 23.4 µg/L) and SELENOP (3.0 ± 1.4 vs. 4.3 ± 1.0 mg/L) concentrations. A Se status below the 2.5th percentile of the reference population, i.e., [Se] < 45.7 µg/L and [SELENOP] < 2.56 mg/L, was present in 43.4% and 39.2% of COVID samples, respectively. The Se status was significantly higher in samples from surviving COVID patients as compared with non-survivors (Se; 53.3 ± 16.2 vs. 40.8 ± 8.1 µg/L, SELENOP; 3.3 ± 1.3 vs. 2.1 ± 0.9 mg/L), recovering with time in survivors while remaining low or even declining in non-survivors. We conclude that Se status analysis in COVID patients provides diagnostic information. However, causality remains unknown due to the observational nature of this study. Nevertheless, the findings strengthen the notion of a relevant role of Se for COVID convalescence and support the discussion on adjuvant Se supplementation in severely diseased and Se-deficient patients.
Article
Atherosclerosis, a chronic inflammatory disease of the arterial wall, is the leading cause of cardiac disorders and stroke. The onset and progression of these diseases are linked with the inflammatory response, especially NLRP3 inflammasome activation, inducing the production of proinflammatory cytokines, such as interleukin 1β (IL-1β). Because high-density lipoproteins (HDLs) have shown significant antiatherogenic and anti-inflammatory properties, we evaluated their immunomodulatory activity in response to cholesterol crystals and other innate immune activators. Human primary monocyte-derived macrophages, THP-1 cells, and murine macrophages were stimulated to activate NLRP3 inflammasome and other pattern recognition receptors, in the presence or absence of HDL. Then, HDL immunomodulatory effects were evaluated through IL-1β and IL-6 production by enzyme-linked immunosorbent assay. Furthermore, in vivo HDL anti-inflammatory effects were evaluated in a murine model of peritoneal inflammatory infiltration. HDLs have an immunomodulatory effect on different cellular models, including peripheral blood mononuclear cells, THP-1 cells, and murine macrophages, by affecting the activity of innate immunity sensors, such as Toll-like receptors (TLRs), dectin-1, and inflammasomes. HDL reduces the proinflammatory role of cholesterol crystals, nigericin, and other NLRP3 and AIM2 inflammasome agonists, and several TLR agonists, leading to a decreased production of IL-1β and IL-6. The results suggest that HDLs are highly important in the regulation of the innate immune response and may have a beneficial role in controlling diseases associated with the inflammatory response.
Article
Background: The global prevalence of type 2 diabetes continues to increase in both developed and developing countries. Environmental exposure to mercury may be an important and modifiable risk factor for type 2 diabetes. However, the epidemiological results are controversial. Objectives: This study aimed to examine the association between blood mercury levels and prevalence of type 2 diabetes. Methods: A total of 646 adult participants were selected from the National Nutrition and Health Survey in Taiwan (NAHSIT) 2005-2008. The participants were interviewed using structured questionnaires to record data on basic demographics, socioeconomic status, lifestyle, medical history, and 24-h dietary recall. Specimens of blood and urine were collected at the health examination. Type 2 diabetes was defined as a fasting blood glucose level ≥ 126 mg/dL or intake of hypoglycemic medications. The mercury concentration in red blood cells (RBC-Hg) was quantified by cold vapor atomic absorption spectrometry. Results: Participants with type 2 diabetes had a significantly higher RBC-Hg than those without type 2 diabetes. A significant association between the RBC-Hg and prevalence of type 2 diabetes was observed [odds ratio (OR): 1.64; 95% confidence intervals: 1.14-2.35] after potential confounders were well considered, including age, sex, body mass index (BMI), hypertension, total cholesterol, saltwater fish consumption, geographical strata, seasonality and hemoglobin (Hb) level. Conclusion: Our findings showed that elevated RBC-Hg is significantly associated with type 2 diabetes prevalence. Future research, particularly for longitudinal cohort studies with suitable specimens, needs to be performed to verify our findings.
Article
Background: Mechanistic studies support the potential for mercury (Hg) to alter immunity, including via in utero exposure. As yet, there are few prospective studies of in utero Hg exposure and subsequent immune-related outcomes, especially in infancy. Objectives: We investigated the association of biomarkers of prenatal Hg exposure and maternal silver-mercury dental amalgams with the occurrence of infant allergy, respiratory infection, and respiratory symptoms in the first year of life. Methods: The New Hampshire Birth Cohort Study (NHBCS) ascertained information on infant allergies, infections and symptoms through telephone interviews at 4, 8 and 12 months postpartum and measured total Hg in maternal toenails collected at ~28-30 weeks gestation. Information on maternal fish consumption and presence of dental amalgams was obtained from a questionnaire administered at study enrollment at 24-28 weeks. A total of 1321 NHBCS mother-infant pairs had at least one Hg exposure measure (toenail Hg or information on dental amalgams) and information on dietary fish intake. Generalized linear models and generalized estimating equation models with Poisson regression adjusted for potential confounders (maternal age, level of education, parity, smoking, alternative Healthy Eating Index-2010, infant sex, gestational age, feeding mode, and day care attendance) were used to assess the association between infant outcomes and prenatal toenail Hg levels. We subsetted this analysis on mothers who consumed fish (n = 706) as a measure of in utero methylmercury (MeHg) exposure. Associations between infant outcomes and dental amalgams as a measure of in utero inorganic Hg exposure were assessed among mothers who did not consume fish (n = 218). Results: Among women who ate fish during pregnancy, higher maternal toenail Hg concentrations were associated with an increased risk of lower respiratory infections and respiratory symptoms requiring a doctor visit among infants age 9-12 months (relative risk (RR) 1.4 (95% CI: 1.1, 1.9) and 1.2 (95% CI: 1.0, 1.4) respectively), whereas a reduced risk of lower respiratory infections was observed among infants 0-4 months of age (RR = 0.7 (95% CI: 0.5, 1.0). We found little to no evidence of associations of toenail Hg with upper respiratory infections, allergy or eczema at any age to one year. Among infants of mothers who did not consume fish, we found an elevated risk of upper respiratory infections requiring a doctor visit in relation to having dental amalgams during pregnancy (RR = 1.5 (95% CI: 1.1, 2.1)). Overall, weaker associations were observed with lower respiratory infections, respiratory symptoms, and medically confirmed allergies, and there was no association with eczema. Conclusions: Our analyses of a US birth cohort, along with prior mechanistic work, raise the possibility that gestational Hg exposure through fish/seafood consumption and dental amalgams may alter respiratory infections and respiratory symptoms in infants.
Article
Background Some heavy metals (e.g., arsenic, cadmium, lead, mercury) have been associated with obesity and obesity comorbidities. The analytical approach for those associations has typically focused on individual metals. There is a growing interest in evaluating the health effects of cumulative exposure to metal mixtures. Objectives We utilized our Environmental Risk Score (ERS), a summary measure to examine the risk of exposure to multi-pollutants in epidemiologic research, to evaluate the associations of cumulative exposure to a mixture of correlated heavy metals with obesity and its comorbidities including hypertension, and type-2 diabetes mellitus (T2DM) while accounting for high degree correlations and interactions among metal mixtures components. Methods We examined blood and urinary markers of 18 heavy metals among 9537 adults in NHANES 2003–2014. We randomly split data into a training set for the construction of ERS (n = 6675) and a testing set for the evaluation of its statistical performance (n = 2862). ERS of heavy metal mixtures was computed for waist circumference using adaptive elastic-net (AENET) with 189 predictors including 18 main effects, 18 squared terms, and 153 pairwise interactions of heavy metals. Regression analyses with complex survey designs were performed to assess the associations of ERS with other obesity measures, hypertension and T2DM. Results 7 main effects (blood lead, blood cadmium, blood mercury, and urinary markers of monomethylarsonic acid (MMA), barium, mercury and thallium), 4 squared terms (blood cadmium, urinary cadmium, urinary antimony and urinary tungsten), and 7 pairwise interactions (blood lead & urinary cadmium, blood lead & urinary MMA, blood lead & urinary uranium, urinary cadmium & urinary MMA, urinary dimethylarsinic acid (DMA) & urinary tungsten, urinary MMA & urinary cobalt, and urinary lead & urinary antimony) were selected by AENET for construction of ERS of waist circumference-related metal mixtures. An increase in ERS from 10th percentile to 90th percentile in the overall study population was significantly associated with 4.50 kg/m2 (95% CI: 4.06, 4.94) higher BMI, 4.16 mm (95% CI: 3.56, 4.76) higher skinfold thickness, and 4.11 kg (95% CI: 0.83, 7.40) higher total body fat, independent of age, sex, race/ethnicity, education, smoking status, physical activity and NHANES cycle (Ps < 0.05). Significant associations of ERS with both hypertension and T2DM were also observed (Ps < 0.05). Conclusions Our study suggests that cumulative exposure to heavy metals as mixtures is associated with obesity and its related chronic conditions such as hypertension and T2DM. Additional research is needed to confirm these findings in longitudinal settings.
Article
Background: Body burden of mercury has been linked to hypertension in populations exposed to high mercury levels. Objectives: We summarized, extracted, and pooled the results of published studies that investigated mercury biomarkers and hypertension or blood pressure (BP) measurements to examine this potential relationship. Methods: We searched PubMed, Embase, and TOXLINE and selected studies according to a priori defined inclusion criteria. Study quality was assessed by the Newcastle-Ottawa scale for cohort and case-control studies and the Quality Assessment Tool for cross-sectional studies. Study estimates were pooled using inverse-variance weighted random-effects models. Dose-response meta-analysis was performed with studies reporting hypertension and systolic BP for at least three mercury categories. Results: A total of 29 studies were included in the meta-analysis. The pooled odds ratio (OR) for hypertension, comparing the highest and lowest mercury exposure categories, was 1.35 [95% confidence interval (CI): 0.99, 1.83] for populations with hair mercury ≥2 μg/g in comparison with the OR of 1.12 (95% CI: 0.82, 1.52) for populations with hair mercury <2 μg/g. Positive associations were also observed for highest versus lowest mercury exposure categories on systolic and diastolic BP. Heterogeneity was observed for mercury species and exposure groups across different studies. Associations estimated using different mercury biomarkers generally agree with each other in the same study. A nonlinear dose-response relationship with an inflection point at 3 μg/g was identified, for both hypertension and systolic BP. Conclusions: A significant positive association between mercury and hypertension and between mercury and BP was identified. The exposure dose is an important factor in determining the toxic effects of mercury on hypertension. https://doi.org/10.1289/EHP2863.
Article
Background Lead acetate (Led) and mercury chloride (Mer) represent important ecological and public health concerns due to their hazardous toxicities. Naturally found products play a vital role in chemopreventive agent innovation. The current study aimed to assess the modifying effect of garlic (Gar) and/or vitamin E (Vit E) against the half-maximal inhibitory concentration (IC50) Led and/or Mer-induced cytotoxic, genotoxic and apoptotic effects. Human lung cells (WI – 38) were pretreated with Gar and/or Vit E for 24 h and then treated with Led and/or Mer either alone or with their combination for 24 h. Cytotoxicity of Led and Mer and the viability of Gar and Vit E were assessed using MTT assay. The alkaline comet assay was used to assess DNA damage, whereas QRT-PCR was performed to evaluate p53, Bax, and Bcl2 mRNA-expression. Results of this study showed that IC50 of Led was (732.72 μg/mL) and for Mer was (885.83 μg/mL), while cell viability effective dose for Gar was (300 μg/mL) and for Vit E was (26800 μg/mL). Treating cells with the IC50-concentration of Led or Mer or their combination using half IC50 of both of them induced severe DNA-damage. Bax-expression was increased, while p53 and Bcl2-expressions were decreased. Pretreatment of cells with Gar and/or Vit E ameliorated the previous alternations. In conclusion Led and Mer can induce oxidative stress and change the expressions of apoptosis-related proteins in WI-38 cells. Gar and Vit E may be promising protective candidate agent against the toxic effect of heavy metals.
Article
Purpose: To evaluate the effect of supplemental selenium administration on the incidence of ventilator-associated pneumonia (VAP) in critically ill patients. Methods: Ninety-nine mechanically ventilated patients were randomized to receive either selenium or isotonic saline infusion for 10days. The primary endpoint was serum glutathione peroxidase-3 (GPX-3) activity and secondary endpoints were development of VAP or death, ICU stay and vasopressor requirement. Serum concentrations of selenium and GPX-3 were measured on Day-1, Day-4 and Day-10. Chi Square and log-rank analyses were used for statistical analyses and odds ratios were calculated. Results: Serum selenium and GPX-3 activity levels increased steadily in the treatment group within 10days (P<0.025), while they remained unchanged in the placebo group. The incidence of VAP was 19.4/1000days of mechanical ventilation in the placebo group while it was 15.8/1000 ventilated days in the treatment group (P=0.250). The risk of VAP or death was similar between the treatments and placebo groups. Conclusion: Despite increasing the antioxidant activity, selenium supplementation did not affect the incidence of VAP in critically ill patients. The risk of developing VAP or death within 30days of ICU admission remained the same in the treatment and the controls.
Article
Mercury (Hg) and 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) are major environmental contaminants that commonly co-occur in the environment. Both Hg and TCDD are associated with a number of human diseases including cancers. While the individual toxicological effects of Hg and TCDD have been extensively investigated, studies on co-exposure are limited to a few genes and pathways. Therefore, a significant knowledge gap exists in the understanding of the deleterious effects of co-exposure to Hg and TCDD. Due to the prevalence to Hg and TCDD co-contamination in the environment and the major human health hazards they pose, it is important to obtain a fuller understanding of genome-wide effects of Hg and TCDD co-exposure. In this study, by performing a comprehensive transcriptomic analysis of human bronchial epithelial cells (BEAS-2B) exposed to Hg and TCDD individually and in combination, we have uncovered a subset of genes with altered expression only in the co-exposed cells. We also identified additive as well as antagonistic effects of Hg and TCDD on gene expression. Moreover, we found that co-exposure impacted several biological and disease processes not affected by Hg or TCDD individually. Our studies show that consequences of Hg and TCDD co-exposure on the transcriptional program and biological processes could be substantially different from single exposures, thus providing new insights into the co-exposure-specific pathogenic processes.
Article
Background: Although mercury exposure has been associated with several adverse health effects, the association with childhood asthma is under-investigated. Therefore, we explore the association between mercury and childhood asthma in a population with low mercury levels. Methods: Mercury levels were measured in blood and urine in 1,056 children aged 5-14 years. In addition to including questions about asthma diagnosis and wheezing, the study measured bronchial hyper-responsiveness and allergic sensitization to common aeroallergens. Logistic regression analysis adjusted for major potential confounders. Results: Overall the adjusted odds ratios (aOR) between log blood mercury and the outcomes were 0.8 (95% CI 0.63, 1.11) for asthma, 0.9 (95% CI 0.79, 1.14) for wheeze, 1.1 (95% CI 0.60, 2.03) for bronchial hyperresponsiveness, and 1.0 (95% CI 0.80, 1.17) for allergic sensitization. Urine mercury adjusted for creatinine was also not associated with any of these allergy-related outcomes. Conclusions: While the results did not support an association between mercury exposure and asthma, studies are needed to assess prenatal and lifetime exposure to mercury and asthma.
Article
The mercurial forms [inorganic divalent mercury, Hg(II) and methylmercury, CH3Hg] produce neurological and immune effects as well as hematological and renal alterations. The main route of exposure is through the diet. Consequently, the gastrointestinal mucosa is exposed to these mercurial forms, though the potential toxic effects upon the mucosa are not clear. The present study evaluates the toxicity of Hg(II) and CH3Hg (0.1-2 mg/L) in an intestinal epithelium model using the differentiated and undifferentiated human Caco-2 cell line. The experiments made show the mercurial forms generate reactive oxygen and/or nitrogen species and a significant decrease in glutathione contents. This redox imbalance could be the cause of the lipid peroxidation observed after short exposure times. Such conditions of stress lead to a modulation of stress proteins, intercellular junction proteins and tumor necrosis factor-alpha expression and to a redistribution of F-actin and ZO1 protein in the intestinal monolayer. The abovementioned effects may be the cause of the increase in permeability in the differentiated cells observed at concentrations similar to those found in food products (0.5-1 mg/L). The increase in permeability could produce an impairment of the barrier function of the intestinal epithelium. Copyright © 2014 Elsevier Ltd. All rights reserved.
Article
Interest is increasing in the content of toxic metals in cigarette smoke for both their harmful health effects and the possible antagonistic influence with the essential microelements. Numerous factors influence the metal concentration found in tobacco, including soil type and pH, genotype, stalk position, application of metal-containing pesticides to leaves. The rate of transfer to the smoke is dependent on the volatility, the temperature and the filter-type. In cigarette smoke element concentrations vary among brands and even within the same brand. No comprehensive information is yet available on the toxic heavy metal content of the major Hungarian cigarette-brands. The purpose of the study was to obtain current information on the metal contents of selected brands of cigarettes being sold in Hungary. The work described in this paper had two objectives: firstly to determine the cadmium, lead, zinc and iron content of raw materials (tobacco-cut, cigarette paper, filter-rod) and secondly to measure the amount of these metals in the combustion products (cigarette smoke, ash, filter-rod). Non-negligible part of the toxic metal content of the tobacco cut gets into the mainstream smoke, but the measured values are not higher than the similar data published in the international literature. Filters are not really efficient to decrease the toxic metal content of the mainstream smoke. The toxic metal concentration in the sidestream smoke is higher than in the mainstream smoke.
Article
Exhaled nitric oxide (NO) levels as a noninvasive biomarker of airway inflammation and have been used to monitor environmental health effects. Mercury is a toxic environmental pollutant and is probable immunotoxic substance. We examined the association between blood mercury levels and exhaled NO levels in a representative sample of US adults. This investigation was a cross-sectional study of 3,564 adults (⩾20 years of age) who participated in the 2007-2008 National Health and Nutrition Examination Survey and provided measurements of exhaled NO and blood mercury levels. The exhaled NO measurements relied on the 2005 American Thoracic Society and European Respiratory Society equipment recommendations, and the mercury levels were measured using inductively coupled plasma mass spectrometry. The overall geometric mean values were 13.7 ng/g for exhaled NO and 0.97 μg/L for blood mercury. The subjects with mercury levels within the 4th quartile showed significantly increased exhaled NO levels [ß = 0.202; 95% CI, 0.104 to 0.300]. Moreover, this association remained robust after risk factors related to exhaled NO levels and mercury exposure were adjusted for. Additionally, as the blood mercury levels increased, the adjusted mean levels of exhaled NO increased in a dose-dependent manner. Our study observed that blood mercury levels were significantly associated with elevated exhaled NO levels in US adults. This study implies the importance of exhaled NO as a measurement to assess health risks of environmental pollutants such as mercury.
Article
The devastating link between tobacco products and human cancers results from a powerful alliance of two factors - nicotine and carcinogens. Without either one of these, tobacco would be just another commodity, instead of being the single greatest cause of death due to preventable cancer. Nicotine is addictive and toxic, but it is not carcinogenic. This addiction, however, causes people to use tobacco products continually, and these products contain many carcinogens. What are the mechanisms by which this deadly combination leads to 30% of cancer-related deaths in developed countries, and how can carcinogen biomarkers help to reveal these mechanisms?
Article
J Clin Hypertens (Greenwich). 2011;13:621–627. ©2011 Wiley Periodicals, Inc. Mercury has a high affinity for sulfhydryl groups, inactivating numerous enzymatic reactions, amino acids, and sulfur-containing antioxidants (N-acetyl-L-cysteine, alpha-lipoic acid, L-glutathione), with subsequent decreased oxidant defense and increased oxidative stress. Mercury binds to metallothionein and substitute for zinc, copper, and other trace metals, reducing the effectiveness of metalloenzymes. Mercury induces mitochondrial dysfunction with reduction in adenosine triphosphate, depletion of glutathione, and increased lipid peroxidation. Increased oxidative stress and reduced oxidative defense are common. Selenium and fish containing omega-3 fatty acids antagonize mercury toxicity. The overall vascular effects of mercury include increased oxidative stress and inflammation, reduced oxidative defense, thrombosis, vascular smooth muscle dysfunction, endothelial dysfunction, dyslipidemia, and immune and mitochondrial dysfunction. The clinical consequences of mercury toxicity include hypertension, coronary heart disease, myocardial infarction, cardiac arrhythmias, reduced heart rate variability, increased carotid intima-media thickness and carotid artery obstruction, cerebrovascular accident, generalized atherosclerosis, and renal dysfunction, insufficiency, and proteinuria. Pathological, biochemical, and functional medicine correlations are significant and logical. Mercury diminishes the protective effect of fish and omega-3 fatty acids. Mercury inactivates catecholaminei-0-methyl transferase, which increases serum and urinary epinephrine, norepinephrine, and dopamine. This effect will increase blood pressure and may be a clinical clue to mercury-induced heavy metal toxicity. Mercury toxicity should be evaluated in any patient with hypertension, coronary heart disease, cerebral vascular disease, cerebrovascular accident, or other vascular disease. Specific testing for acute and chronic toxicity and total body burden using hair, toenail, urine, and serum should be performed.
Article
To confirm the pharmacodynamics and evaluate the efficacy of high-dose selenium (Se) administered by continuous infusion, following an initial loading bolus of selenite, on clinical outcome in critically ill patients with systemic inflammatory response syndrome (SIRS). Prospective, placebo-controlled, randomized, single-blinded phase II study in a multidisciplinary university hospital intensive care unit (ICU). Two groups of patients with SIRS, age >18 years, and Acute Physiology and Chronic Health Evaluation (APACHE) II ≥15 (n = 35) were randomized to receive either placebo or intravenous selenite as a bolus-loading dose of 2,000 μg Se followed by continuous infusion of 1,600 μg Se per day for 10 days. Blood samples were analyzed before randomization (day 0) then at days 3, 7, and 10. Clinical outcome was assessed by Sequential Organ Failure Assessment (SOFA) score. Hospital-acquired pneumonia including ventilator-associated pneumonia (VAP), adverse events, and other safety parameters were monitored as secondary endpoints. SOFA score decreased significantly in the selenite group at day 10 (1.3 ± 1.2 versus 4.6 ± 2.0, p = 0.0001). Early VAP rate was lower in the selenite group (6.7% versus 37.5%, p = 0.04), and hospital-acquired pneumonia was lower after ICU discharge (p = 0.03). Glutathione peroxidase-3 (GPx-3) activity increased in both groups, reaching a maximum at day 7 (0.62 ± 0.24 versus 0.28 ± 0.14 U/mL, p = 0.001) in the selenite group. No adverse events attributable to selenite were observed. Daily infusion of 1,600 μg Se (as selenite), following an initial bolus of 2,000 μg, is novel and without short-term adverse events. High-dose parenteral selenite significantly increases Se status, improves illness severity, and lowers incidence of hospital-acquired pneumonia including early VAP for SIRS patients in ICU.
Article
Recently emerged viral infectious diseases (VIDs) include HIV/AIDS, influenzas H5N1 and 2009 H1N1, SARS, and Ebola hemorrhagic fevers. Earlier research determined metabolic oxidative stress in hosts deficient in antioxidant selenium (Se) (<1 μMol Se/L of blood) induces both impaired human host immunocompetence and rapidly mutated benign variants of RNA viruses to virulence. These viral mutations are consistent, rather than stochastic, and long-lived. When Se-deficient virus-infected hosts were supplemented with dietary Se, viral mutation rates diminished and immunocompetence improved. Herein is described the role of micronutrient Se deficiency on the evolution of some contemporary RNA viruses and their subsequent VIDs. Distinguishing cellular and biomolecular evidence for several VIDs suggests that environmental conditions conducive to chronic dietary Se deprivation could be monitored for bioindicators of incipient viral virulence and subsequent pathogenesis.
Article
The aim of the study is to investigate the levels of toxic heavy metals related with environmental pollution and trace elements involved in antioxidant system in children suffering from recurrent wheezing. One hundred children with recurrent wheezing (at least three recurrences) between the ages from 1 to 6 years took part in the study, and also 116 age- and sex- matched healthy children were involved in the study as a control group. Venous blood samples were collected and serum mercury, lead, aluminium, zinc, selenium, and copper levels were studied using ICP-MS. Serum lead (0.76±0.15 vs. 0.27±0.01, p:0.001) and mercury levels (1.31±0.15 vs 0.71±0.05, p<0.001) were higher in wheezy group than those acquired from the control group. Serum zinc (69.4±1.65 vs. 78.9±2.78, p:0.005) and selenium (115.6±1.87 vs. 125.4±2.94, p:0.008) levels were lower in wheezy group than those acquired from the control group. Serum zinc levels were found to be correlated with number of ARTIs (r(p):-0.332, p:0.001) and the number of wheezy attacks (r(p):-0.776, p<0.001) during the previous year in the wheezy group. Elevated levels of serum lead and mercury and low levels of zinc and selenium may suggest some disturbances in the antioxidant system in children with recurrent wheezing. This means that children with recurrent wheezing are much more susceptible to environmental pollutants and respiratory tract infections than healthy children and this heavy metal-antioxidant relationship may play a role as a contributing factor in the pathogenesis of recurrent wheezing in children.
Article
The mechanism of transport of trace elements from the mother to the newborn is still not well known. The aim of present study was to compare the status of trace toxic elements, arsenic (As), cadmium (Cd), and lead (Pb) in biological samples (whole blood, urine and scalp hair) of insulin-dependent diabetic mothers (age ranged 30-40) and their newly born infants (n = 76). An age and socioeconomics matched 68 nondiabetic mothers and their infants, residing in the same locality, who were selected as referents. The elemental concentrations in all three biological samples were determined by an electrothermal atomic absorption spectrometer, prior to microwave-assisted acid digestion. The mean values of As, Cd, and Pb in all biological samples of diabetic mothers and their infants were significantly higher as compared to the referent mother-infant pair samples (p < 0.01). The high levels of As, Cd, and Pb in biological samples of diabetic women may play a role in the pathogenesis of diabetes mellitus and impacts on their neonates.