Zinc, Copper, and Selenium Tissue Levels and Their Relation to Subcutaneous Abscess, Minor Surgery, and Wound Healing in Humans

Trace element involvement in wounds left to heal by secondary intention needs clarification. We have previously reported faster healing of wounds following acute surgery compared with elective excision of pilonidal sinus disease. The effect of topical zinc on the closure of the excisional wounds was mediocre compared with placebo. In contrast, parenteral zinc, copper, and selenium combined appear effective for wound healing in humans. We have investigated zinc, copper, and selenium with respect to (a) impact of acute versus chronic pilonidal sinus and (b) regional concentrations within granulating wounds treated topically with placebo or zinc in 42 (33 males) pilonidal disease patients. Baseline serum and skin concentrations of copper correlated (r _S?=?0.351, p?=?0.033, n?=?37), but not of zinc or selenium. Patients with abscesses had elevated serum C-reactive protein (CRP) and copper levels (+29 %; p?<?0.001) compared with the elective patients consistent with the strong correlation between serum copper and CRP (r _S?=?0.715, p?<?0.0005, n?=?41). Seven days after elective surgery, serum CRP and copper levels were elevated (p?=?0.010) versus preoperative values. The copper concentration in wound edges was higher than in periwound skin (p?<?0.0005) and wound base (p?=?0.010). Selenium levels were increased in wound edge compared to wound base (p?=?0.003). Topical zinc oxide treatment doubled (p?<?0.050) zinc concentrations in the three tissue localizations without concomitant significant changes of copper or selenium levels. In conclusion, copper and selenium are mobilized to injured sites possibly to enhance host defense and early wound healing mechanisms that are complementary to the necessity of zinc for matrix metalloproteinase activity.     

Plasma and liver selenium levels in the rat during supplementation with 0.5, 2, 6, and 15 ppm selenium in drinking water

Plasma and liver selenium of Wistar rats were determined after 1, 3, and 6 mo supplementation with 0.5, 2, 6, or 15 ppm selenium as sodium selenite in drinking water. Plasma selenium was not different from control values at additional intake of 0.5 ppm but increased above usual levels at higher intakes. A highly significant correlation was observed between the total quantity of selenium ingested and plasma selenium after 1 mo treatment (r=0.99,p<0.01), but was less pronounced after 3 and 6 mo (0.94,p<0.05, and 0.78,p<0.05, respectively). The decrease in plasma selenium with time of treatment was more pronounced at higher intakes. There was also a highly significant correlation between total selenium intake and liver selenium concentration (r=0.99,p<0.01) after 1 mo of treatment, but this time liver selenium did not change with time, and the correlation remained highly significant throughout the investigation. Liver selenium therefore appears as a more sensitive and more representative measure of selenium intake than plasma selenium. Most supplements did not affect body weight and survival of animals, except when the diet was supplemented with 15 ppm for 6 mo; however, alterations in biochemical parameters concerning lipid status and hepatic function were observed at levels above 2.0 ppm.     

Serum selenium versus lymphocyte subsets and markers of disease progression and inflammatory response in human immunodeficiency virus-1 infection

Serum selenium levels were determined cross-sectionally in 57 HIV-infected patients who were classified according to the Centers for Disease Control (CDC) 1993 classification system. Mean serum selenium levels were lower in CDC stage II (58.7±12.2 μg/L;p<0.01;n=18) and stage III (47.6±11.3 μg/L;p<0.01;n=19) HIV-infected patients, than in healthy subjects (80.6±9.6 μg/L;n=48) and stage I patients (73.6±16.5 μg/L;n=20). Serum selenium levels were positively correlated with CD4 count, CD4/8 ratio, hematocrit, and serum albumin (r=0.42;r=0.39;r=0.48; andr=0.45;p<0.01, respectively) and inversely with serum levels of thymidine kinase (r=−0.49;p<0.01;n=49) and β2-microglobulin (r=−0.46;p<0.001;n=49). In addition, serum selenium levels in 20 randomly selected AIDS-free individuals (CDC I:n=10; CDC II:n=10) were inversely correlated with serum concentrations of interleukin-8 (IL-8) and soluble tumor necrosis factor receptors (sTNFR) types I and II. There was no correlation with serum immuneglobulin A and total serum protein levels. The results show that the progressive deprivation of serum selenium in HIV-infection is associated with loss of CD4⁺-cells and with increased levels of markers of disease progression and inflammatory response.     

High-Precision (MC-ICPMS) Isotope Ratio Analysis Reveals Contrasting Sources of Elevated Blood Lead Levels of an Adult with Retained Bullet Fragments,and of His Child,in Milwaukee,Wisconsin

This study aimed at evaluation of a relationship between blood selenium concentration (Se-B) and blood cystatin C concentration (CST) in a randomly selected population of healthy children, environmentally exposed to lead and cadmium. The studies were conducted on 172 randomly selected children (7.98 ± 0.97 years). Among participants, the subgroups were distinguished, manifesting marginally low blood selenium concentration (Se-B 40–59 μg/l), suboptimal blood selenium concentration (Se-B: 60–79 μg/l) or optimal blood selenium concentration (Se-B ≥ 80 μg/l). At the subsequent stage, analogous subgroups of participants were selected separately in groups of children with BMI below median value (BMI <16.48 kg/m²) and in children with BMI ≥ median value (BMI ≥16.48 kg/m²). In all participants, values of Se-B and CST were estimated. In the entire group of examined children no significant differences in mean CST values were detected between groups distinguished on the base of normative Se-B values. Among children with BMI below 16.48 kg/m², children with marginally low Se-B manifested significantly higher mean CST values, as compared to children with optimum Se-B (0.95 ± 0.07 vs. 0.82 ± 0.15 mg/l, p < 0.05). In summary, in a randomly selected population of healthy children no relationships could be detected between blood selenium concentration and blood cystatin C concentration. On the other hand, in children with low body mass index, a negative non-linear relationship was present between blood selenium concentration and blood cystatin C concentration.     

Levels of Selenium, Zinc, Copper, and Cardiac Troponin I in Serum of Patients with Acute Coronary Syndrome

The aim of this study was to assess the levels of selenium (Se), zinc (Zn), copper (Cu), and troponin I (TnI) in patients with acute coronary syndrome (ACS) on admission to our emergency department in comparison to healthy control subjects. Patients with diagnosed ACS (n?=?100) were included in the study group. Control subjects (n?=?100) were selected from healthy volunteers in the same age range. Venous blood samples were obtained to evaluate the levels of Se, Zn, Cu, and TnI (on admission for the ACS group). Serum Se, Zn, and Cu levels were significantly less in the ACS group compared to the control group (p <0.001, p <0.01, and p <0.001, respectively). The serum TnI level was significantly greater in the ACS group compared to the control group (p <0.05). The serum Se level in the ACS group correlated significantly with the TnI level (r?=??0.211, p?=?0.035). These results indicate that Se, Zn, and Cu deficiencies may be risk factors for ACS, and a decreased serum Se level in patients with ACS might reflect the degree of myocardial necrosis.     

Hair Mercury Association with Selenium,Serum Lipid Spectrum,and Gamma-Glutamyl Transferase Activity in Adults

The primary objective of the research is to estimate the dependence between hair mercury content, hair selenium, mercury-to-selenium ratio, serum lipid spectrum, and gamma-glutamyl transferase (GGT) activity in 63 adults (40 men and 23 women). Serum triglyceride (TG) concentration in the high-mercury group significantly exceeded the values obtained for low- and medium-mercury groups by 72 and 42 %, respectively. Serum GGT activity in the examinees from high-Hg group significantly exceeded the values of the first and the second groups by 75 and 28 %, respectively. Statistical analysis of the male sample revealed similar dependences. Surprisingly, no significant changes in the parameters analyzed were detected in the female sample. In all analyzed samples, hair mercury was not associated with hair selenium concentrations. Significant correlation between hair mercury content and serum TG concentration (r?=?0.531) and GGT activity (r?=?0.524) in the general sample of the examinees was detected. The respective correlations were observed in the male sample. Hair mercury-to-selenium ratios significantly correlated with body weight (r?=?0.310), body mass index (r?=?0.250), serum TG (r?=?0.389), atherogenic index (r?=?0.257), and GGT activity (r?=?0.393). The same correlations were observed in the male sample. Hg/Se ratio in women did not correlate with the analyzed parameters. Generally, the results of the current study show the following: (1) hair mercury is associated with serum TG concentration and GGT activity in men, (2) hair selenium content is not related to hair mercury concentration, and (3) mercury-to-selenium ratio correlates with lipid spectrum parameters and GGT activity.     

The Relationship Between Selenium Levels and Breast Cancer: A Systematic Review and Meta-Analysis

Breast cancer is the most common cancer type. In several studies, hints have been provided that there is a correlation between selenium deficiency and the incidence of breast cancer. Findings of these published reports are, however, inconsistent. This study serves as a pioneering study aiming at combining the results of studies using a meta-analytic method. A total of 16 articles published between 1980 and 2012 worldwide were selected through searching PubMed, Scopus, and Google scholar databases, and the information were analyzed using a meta-analytic method [random effects model]. I ² statistics were used to examine heterogeneity. The information was then analyzed by STATA version 12. In this study, due to the non-uniform methods used to measure selenium concentrations, selenium levels were measured in the various subgroups in both case and control groups. There were significant correlations between selenium concentration and breast cancer [P?<?0.05]. Hence, the mean risk differentiating criteria were estimated to be 0.63 [95 % confidence interval [95% CI] 0.93 to 0.32] in serum and toenails. Subgroup analysis showed that the value in toenails was ?0.07 [95% CI ?0.16 to 0.03] and in serum ?1.04 [95% CI 1.71 to ?0.38]. In studies in which selenium concentrations were measured in serum, a significant correlation was observed between selenium concentration and breast cancer. In contrast, in studies in which selenium concentration was measured in toenails, the correlation was not significant. Therefore, the selenium concentration can be used as one predictor for breast cancer.     

Determination of some elements in the cervical mucus of healthy Taiwanese women,by GF-AAS

The levels of seven trace elements such as copper, iron, zinc, selenium, cadmium, chromium, and nickel were determined by graphite furnace-atomic absorption spectrometry in the cervical mucus of 45 women residing in Taiwan, Republic of China. These women were in good health and had no precancerous or cancerous lesions on their cervix. The women were separated into four age groups to establish if there was a relationship between the age of the subjects and the values of these elements in the cervical mucus. By one-way analysis of variance, significant differences in the selenium and nickel concentrations were found among the four age groups (p<0.05). The mean concentration of selenium in each age group was significantly higher for the older women. A significant correlation between age and selenium concentration was found by linear regression (r=0.23, p=0.00048). No significant differences among the concentrations of copper, iron, zinc, cadmium, and chromium were found among these four age groups (p>0.05). The results presented in this work may be considered as baseline values for these elements in the cervical mucus of healthy Taiwanese women for use as reference in studies on cervical diseases and tissue damage.     

Selenium, Zinc, and Copper Plasma Levels in Patients with Schizophrenia: Relationship with Metabolic Risk Factors

The aim of this study was to determine the plasma selenium (Se), copper (Cu), and zinc (Zn) levels and to evaluate their possible association with metabolic syndrome (MetS) components in patients with schizophrenia. The study group consisted of 60 patients with schizophrenia and 60 sex- and age-matched healthy controls. Anthropometric measurements, blood pressure, and biochemical analysis of fasting blood were performed in all subjects. Patients with schizophrenia had significantly higher plasma Cu concentrations compared with controls (0.97?±?0.31 vs. 0.77?±?0.32 mg/L, p?=?0.001). The plasma Cu concentration showed a positive correlation with plasma glucose and diastolic blood pressure in the patient groups (r _s ?=?0.263, p?<?0.05 and r _s ?=?0.272, p?<?0.05, respectively). The plasma Se level correlated positive with MetS score (r _s ?=?0.385, p?<?0.01), waist circumference (r _s ?=?0.344, p?<?0.05), plasma glucose (r _s ?=?0.319, p?<?0.05), and triglyceride concentrations (r _s ?=?0.462, p?<?0.001) in patients with schizophrenia. Plasma Zn did not correlate with any of the MetS components. These results suggest that alterations in plasma Cu and Se levels in medicated patients with schizophrenia could be associated with metabolic risk factors.     

Hair Mineral and Trace Element Contents as Reliable Markers of Nutritional Status Compared to Serum Levels of These Elements in Children Newly Diagnosed with Inflammatory Bowel Disease

Patients with inflammatory bowel disease (IBD) are at high risk for nutritional deficiencies because of long-term inflammation in the gut mucosa and decreased oral intake. Because inflammation responses affect serum micronutrient concentrations, serum levels are limited in reflecting body nutrient status in acute and chronic illness. We investigated the usefulness of measuring trace elements in hair as reliable markers of nutritional status compared to serum levels in children with IBD. We retrospectively analyzed pediatric patients newly diagnosed with Crohn’s disease (n?=?49) and ulcerative colitis (n?=?16) and controls (n?=?29) from 2012 to 2016. Serum micronutrient levels, inflammatory markers, and hair trace element content were evaluated and compared at the time of diagnosis and before initiating treatment. Serum calcium (p?<?0.001), iron (p?<?0.001), zinc (p?=?0.013), selenium (p?=?0.008), albumin (p?<?0.001), prealbumin (p?<?0.001), hemoglobin and hematocrit (p?<?0.001), and WBC (p?=?0.001) and lymphocytes (p?<?0.001) differed significantly between the groups. After adjustment for the erythrocyte sedimentation rate, serum zinc and selenium levels were no longer significantly different between the groups (p?<?0.062 and p?<?0.057, respectively). Following hair analysis for mineral and trace elements, iron (p?=?0.033), selenium (p?=?0.017), and manganese (p?=?0.009) differed significantly between the groups. Serum micronutrient levels need cautious interpretation in conjunction with inflammatory markers. Hair mineral and trace element measurement may support understanding micronutrient status in children with IBD.     

Mercury Transfer During Pregnancy and Breastfeeding: Hair Mercury Concentrations as Biomarker

Hair mercury (HHg) concentration is a biomarker of exposure that is widely used to assess environmental contamination by fish methylmercury and neurodevelopment in children. In the Rio Madeira basin (Brazilian Amazon), total HHg concentrations in 649 mother–infant pairs were measured at birth (prenatal exposure) and after 6 months of exclusive breastfeeding; these mother–infant pairs were from high fish-eating communities (urban, n?=?232; rural, n?=?35; and Riverine, n?=?262) and low fish-eating tin-miner settlers (n?=?120). Differences in kinetics were seen between Hg exposure from fish consumption and environmental exposure to a tin-ore mining environment. Overall maternal HHg concentrations (at childbirth and after 6 months of lactation) were higher than those of infant HHg. However, the relative change in HHg after 6 months of lactation showed that mothers decreased HHg while infants increased HHg. The relative change showed a consistently higher increase for girls than boys with a statistical significance only in high fish-eating mothers. The correlation coefficients between maternal and newborn hair were high and statistically significant for mothers living in urban (r?=?0.66, p?<?0.001), rural (r?=?0.89, p?<?0.001), and Riverine (r?=?0.89, p?<?0.001) communities not for tin miner settlers (r?=?0.07, p?=?0.427). After 6 months of exclusive breastfeeding, correlation coefficients showed high correlation coefficients and statistical significance for all groups (urban, r?=?0.73, p?<?0.001; rural, r?=?0.88, p?<?0.001; Riverine, r?=?0.91, p?<?0.001) except for Tin miners (r?=??0.07, p?=?0.428). A linear model analysis was used to assess the longitudinal associations of maternal total HHg and total HHg at birth (0 days) and 6 months of age in exclusively breastfed infants. Regression analysis significantly predicted HHg in newborn from maternal HHg for high fish-eating maternal-infant pairs. Conclusion: The concentration of mercury accumulated in newborn tissues (in utero and during breastfeeding) relevant to both, maternal sources and infant exposure, can be reliably assessed from maternal hair.     

Serum Total Selenium Status in Greek Adults and Its Relation to Age. The ATTICA Study Cohort

The trace element selenium is an essential micronutrient for human health and its low levels in serum are implicated in the pathogenesis of several chronic diseases. Therefore, the determination of total selenium in serum may contribute to the assessment of the health and nutritional status of certain populations. The objective of the present work was to determine total selenium in the serum of 506 healthy volunteers that participated in the ATTICA study. Selenium was determined in serum by using the technique of inductively coupled plasma mass spectrometry. The mean serum selenium concentration was determined to be 91.8 ± 33.7 μg/L (N = 506); 87.6% of women and 88.5% of men had serum selenium concentration below 125 μg/L, the cutoff considered to be required for optimal glutathione peroxidase activity. No association was found between serum selenium levels and the gender of the participants while a significant decline of selenium with age (p < 0.0001) was observed. According to our results, no anthropometric, lifestyle, nutritional, or biochemical indices were able to affect the association between serum selenium and age. This result may indicate that other factors such as selenium distribution as well as retention may be affecting the relationship between serum selenium and age.     

Correlation of serum trace elements and melatonin levels to radiological, biochemical, and histological assessment of degeneration in patients with intervertebral disc herniation

The aim of our study was to assess the blood concentrations of some trace elements and melatonin (MLT) in patients with intervertebral disc herniation (IDH) and to investigate the interaction of histological and biochemical degeneration findings with aging. The present study was carried out on 13 subjects (8 women and 5 men) diagnosed with IDH. They were divided into three groups according to their ages. Nighttime serum MLT, zinc (Zn), and magnesium (Mg) levels were determined in all patients. In addition, computed tomography (CT) scan of the brain and magnetic resonance imaging examination of the lumbar spine were obtained in this study. The Zn level and Zn/Mg ratio showed a decline in patients with IDH with aging, whereas the serum Mg level and tissue hydroxyproline content increased. A positive correlation between serum Zn and MLT concentrations was found (r=0.104, p=0.734). In addition, there was a positive correlation between serum Zn level and Zn/Mg ratio (r=0.835 and p<0.01), and a negative correlation between serum Mg level and Zn/Mg ratio (r=−0.571, p<0.05). On CT study, both volume percentage of calcified pineal gland and density of calcification were found to increase progressively with advancing age. The results of semiquantitative evaluation of disc tissues of patients with IDH for histological degeneration findings showed that 66.7% of discs treated had slight degeneration in younger age group, but 75.0% and 100% of discs had moderate or marked degeneration in older age groups. Our data indicated that there is a close relationship between MLT and Zn or Mg levels in the serum samples of patients with IDH, and the levels of these elements might be affected by the presence of degeneration process and serum MLT level, or vice versa.     

Association of dietary and serum selenium concentrations with glucose level and risk of diabetes mellitus: A cross sectional study of national health and nutrition examination survey, 1999-2006

BackgroundThe associations among dietary selenium intake, serum selenium concentration, plasma glucose and glycosylated hemoglobin levels, and diabetes risk remain controversial. This study aimed to evaluate these associations in adults from the United States.MethodsWe conducted a cross-sectional study of participants aged 18 years and older who participated in the National Health and Nutrition Examination Survey. Between 1999 and 2006, a total of 41,474 participants were initially included in this study. Multivariable linear or logistic regression analysis was used to investigate the association between dietary selenium intake and serum selenium concentrations, glucose level, and diabetes risk.ResultsThe average age of the participants was 30.32 ± 23.95 years, and 48.72 % were men. Their mean dietary selenium intake and mean serum selenium concentration were 98 ± 55 μg per day and 129 ± 22 ng/mL, respectively. Compared with t he lowest quartile of dietary selenium intake, the highest quartile was associated with elevated plasma glucose levels (β = 2.412, 95 % confidence interval [CI]: 0.420, 4.403, P = 0.018), glycosylated hemoglobin levels (β = 0.080, 95 % CI: 0.041, 0.119, P < 0.001), and diabetes risk (odds ratio [OR] = 2.139, 95 % CI: 1.763, 2.596, P < 0.001). Higher serum selenium was also associated with increased plasma glucose levels (β = 12.454, 95 % CI: 4.122, 20.786, P = 0.003) and glycosylated hemoglobin levels (β = 0.326, 95 % CI: 0.187, 0.465, P < 0.001). A generalized additive model with a spline curve suggested a nonlinear relationship between dietary selenium intake, serum selenium and glucose levels, and diabetes risk.ConclusionsDietary selenium intake and serum selenium were positively associated with elevated levels of plasma glucose and glycosylated hemoglobin, and the relationships were nonlinear. Additional selenium supplementation for patients with diabetes may not be recommended.     

Overweight and Obesity Associated With Increased Total Serum Calcium Level: Comparison of Cross-sectional Data in the Health Screening for Teaching Faculty

Obesity is a risk of cardiovascular diseases. Our previous studies revealed that serum calcium level may have influence in the blood pressure to older male subjects. The aim of this study was to evaluate the relationship between total serum calcium level and overweight and obesity subjects. In our study, overweight and obesity status and total serum calcium level were measured among 2,503 subjects, at age range of 22–94 years, who were recruited for the routine health screening in 2006. The estimated mean for age (p?<?0.001), white blood cell count (p?=?0.037), hemoglobin concentration (p?<?0.001), red blood cell count (p?<?0.001), total serum calcium level (p?<?0.001), total cholesterol weight (p?<?0.001), HDL-cholesterol (p?<?0.001), LDL-cholesterol (p?<?0.001), and triglyceride (p?<?0.001) of overweight and obesity subjects were significantly higher than those of non-overweight subjects. The prevalence of overweight/obesity in subjects according to the log-transformed total serum calcium level quartiles was 16.3–30.5 %. The prevalence of overweight/obesity subjects showed trends that were significant according to the total serum calcium level quartiles (p?<?0.001). The odds ratios (ORs) and 95 % confidence intervals (CIs) for overweight/obesity of the second, third, and fourth quartiles compared to the lowest quartile were 1.407 (1.050–1.883), 1.543 (1.136–2.095), and 1.360 (0.995–1.859), respectively, after adjusting for sex and age (p?<?0.001). These findings suggest that a higher prevalence of adult overweight/obesity is weakly associated with higher total serum calcium level in the Chinese population.     

Selenium status of idiopathic infertile Nigerian males

Selenium concentration in the sera and seminal plasma of 60 infertile males (40 oligospermia and 20 azoospermia) and 40 males with proven evidence of fertility (normospermia; control group) were estimated using atomic absorption spectrophotometry. Results were correlated with spermatogram and hormonal levels in order to determine their relationship and significance in male infertility. The mean serum concentrations of selenium was found to be significantly increased in oligospermic compared to azoospermic subjects and controls (p<0.01), whereas the seminal plasma level was significantly higher in azoospermic compared to oligospermic subjects and controls (p<0.001). Thus, the ratio of serum selenium to seminal plasma selenium was 1∶1 in controls, 4∶1 in oligospermia, and 1∶2 in azoospermic subject. A significant inverse correlation was observed between serum selenium level and sperm count (p<0.01). Similarly, seminal plasma selenium correlated with spermatozoa motility, viability, and morphology. Serum selenium level shows positive correlation with the serum testosterone level (p<0.01). In conclusion, there appears to be a physiological balance in the distribution of selenium in serum and seminal plasma compartment of control males. A disturbance in this balance has a significant influence on spermatogenesis. Selenium appears to have a positive influence on Leydig cells, thus influencing the secretion of testosterone.     

Low selenium status in alcoholic cirrhosis is correlated with aminopyrine breath test

The relationship among impaired selenium status, lipid peroxidation, and liver function was examined in 19 hospitalized patients with severe alcoholic cirrhosis. Plasma selenium was found to be significantly lower (mean±SD: 54±13 μg/L) than in healthy controls (83±11 μg/L) and plasma malondialdehyde, assessed as thiobarbituric acid reactants, which reflects lipid peroxidation, was increased (2.0±1.2 μmol/L vs <1.2 μmol/L in controls). The mean¹⁴C aminopyrine breath test, an indicator of liver function, was lower than normal (2.7±1.9 vs 6.3±0.9% in controls) and found to be significantly correlated with plasma selenium (r=0.59,p<0.05). A prospective, randomized selenium supplementation trial was conducted in a group of 16 patients who received either daily 100 μg selenium as enriched yeast during 4 mo or a placebo. Among the 10 patients who completed the study, plasma selenium significantly increased in the supplemented group (n=4; before: 58±10 μg/L, and after 101±12 μg/L,p<0.01) contrary to the placebo group (n=6, before: 47±10 μg/L, after: 57±9 μg/L, n.s.),¹⁴C aminopyrine breath test improved in three out of four selenium-supplemented patients and in three out of six placebo patients, but the small number of patients did not allow statistical evaluation. These results demonstrate that low selenium status in alcoholic cirrhosis is correlated to liver function and could be improved by supplementation.     

Decreased Serum Selenium Levels are Correlated with Diminished Coronary Flow Reserve Among Hemodialysis Patients

Cardiovascular diseases are the main reason of high mortality among hemodialysis patients. Decreased serum selenium levels may have a role in accelerated atherosclerosis in this patient group. The hypothesis of this study was to show a correlation between decreased serum selenium levels and coronary flow reserve as an indicator of endothelial dysfunction and atherosclerosis in HD patients. Seventy-one chronic hemodialysis patients and age 65 and sex-matched healthy controls were included in the study. Plasma selenium levels were measured by spectrophotometry, and coronary flow reserve was assessed by transthoracic Doppler echocardiography. Serum selenium levels (34.16?±?6.15 ng/ml vs. 52.4?±?5.51 ng/ml, P?<?0.001) and coronary flow reserve values (1.73?±?0.11 vs. 2.32?±?0.28, P?<?0.001) were significantly lower in hemodialysis patients compared with controls, respectively. There was a significant positive correlation between coronary flow reserve and serum levels of selenium (r?=?0.676, P?<?0.001). A linear regression analysis showed that serum levels of selenium were independently and positively correlated with coronary flow reserve (regression coefficient?=?0.650, P?<?0.05). This study was the first to show a positive and independent correlation between decreased selenium levels and diminished coronary flow reserve as an indicator of endothelial dysfunction and atherosclerosis in hemodialysis patients. Our data suggest that decreased serum selenium levels may facilitate the development of endothelial dysfunction and disruption of coronary flow reserve which occur before the development of overt atherosclerosis.     

Concentrations of cadmium,lead, selenium,and zinc in human blood and seminal plasma

The concentrations of cadmium, lead, selenium, and zinc in blood and seminal plasma were determined in 76 Singapore males. Except for zinc, the concentrations were generally higher in blood than in seminal plasma (cadmium, 1.31 μg/L vs 0.61 μg/L; lead, 82.6 μg/L vs 12.4 μg/L, and selenium, 163.6 μg/L vs 71.5 μg/L). The mean concentration of zinc in seminal plasma was more than 30 times higher than in blood (202 mg/L vs 6.2 mg/L). Significant positive correlations were found between the concentrations in blood and seminal plasma for the two essential trace elements: selenium (r=0.45,p<0.001) and zinc (r=0.25,p<0.05). However, no relationships were found between the concentrations in blood and seminal plasma for two toxic metals (cadmium and lead). Significant inverse correlations were observed between Cd and Zn (r=−0.40,p<0.01), and Pb and Se (r=−0.32,p<0.05) in blood, whereas significant positive correlations were noted between Cd and Se (r=0.45,p<0.01), Cd and Zn (r=0.35,p<0.05), and Se and Zn (r=0.57,p<0.001) in seminal plasma. The physiological significance of these relationships are also discussed in this paper.     

Zinc,copper, and zinc- or copper-dependent enzymes in human hypertension

Imbalance of zinc and copper status has been hypothesized in human hypertension. A case-control study was carried out to elucidate the possible relationship between zinc and copper status and essential hypertension. Thirty-one subjects affected by mild stable hypertension, pharmacologically untreated, were investigated together with 31 normotensive controls individually matched for sex, age, and smoking habits. Zinc and copper in serum and urine were measured, and serum activities of alkaline phosphatase (AP), lactic dehydrogenase (LDH), copper-zinc superoxide dismutase (Cu?Zn SOD), lysyl oxidase (LOX), and monoamine oxidase (MAO) were evaluated. No significant difference in serum and urine zinc and copper content as far as in serum activity of zinc (AP and LDH) or copper (Cu?Zn SOD, LOX, and MAO)-dependent enzymes was found between hypertensives and normotensives. Positive relationships were found in normotensives between serum and urine levels of zinc (r=0.577;p=0.001) and copper (r=0.394;p=0.028), and between serum copper and Cu?Zn SOD (r=0.534;p=0.002). In normotensives, diastolic blood pressure and serum zinc were positively related (r=0.370;p=0.041). In hypertensives, inverse correlations were observed between diastolic blood pressure and AP (r=?0.498;p=0.004) and Cu?Zn SOD (r=?0.452;p=0.011), and between systolic blood pressure and LOX (r=?0.385;p=0.033). Diastolic blood pressure was related to LDH inversely in hypertensives (r=?0.357;p=0.049) and positively in normotensives (r=0.457;p=0.010). In normotensives, diastolic blood pressure was inversely related with MAO (r=?0.360;p=0.046). These findings support the hypothesis that an imbalance of zinc and copper status might be involved in human hypertension.