Differences In Zinc Concentrations Research Articles

Pre-analytical variables influence zinc measurement in blood samples.

Zinc deficiency continues to be a major concern for global public health. The zinc status of a target population is typically estimated by measuring circulating zinc levels, but the sampling procedures are not standardized and thus may result in analytical discrepancies. To examine this, we designed a study that controlled most of the technical parameters in order to focus on five pre-analytical variables reported to influence the measurement of zinc in blood samples, including (1) blood draw site (capillary or venous), (2) blood sample matrix (plasma or serum), (3) blood collection tube manufacturer (Becton, Dickinson and Company or Sarstedt AG & Co), (4) blood processing time (0, 4, or 24 hours), and (5) blood holding temperatures (4°C, 20°C, or 37°C). A diverse cohort of 60 healthy adults were recruited to provide sequential capillary and venous blood samples, which were carefully processed under a single chain of custody and measured for zinc content using inductively coupled plasma optical emission spectrometry. When comparing blood draw sites, the mean zinc content of capillary samples was 0.054 mg/L (8%; p<0.0001) higher than venous blood from the same donors. When comparing blood sample matrices, the mean zinc content of serum samples was 0.029 mg/L (5%; p<0.0001) higher than plasma samples from the same donors. When comparing blood collection tube manufacturer, the mean zinc content from venous blood samples did not differ between venders, but the mean zinc content from BD capillary plasma was 0.036 mg/L (6%; p<0.0001) higher than Sarstedt capillary plasma from the same donors. When comparing processing times, the mean zinc content of plasma and serum samples was 5-12% higher (p<0.0001) in samples processed 4-24 hour after collection. When comparing holding temperatures, the mean zinc content of plasma and serum samples was 0.5-7% higher (p = 0.0007 or p = 0.0061, respectively) in samples temporarily held at 20°C or 37°C after collection. Thus even with the same donors and blood draws, significant differences in zinc content were observed with different draw sites, tube types, and processing procedures, demonstrating that key pre-analytic variables can have an impact on zinc measurement, and subsequent classification of zinc status. Minimizing these pre-analytical variables is important for generating best practice guidelines for assessment of zinc status.

Diversity and activity of soil biota at a post-mining site highly contaminated with Zn and Cd are enhanced by metallicolous compared to non-metallicolous Arabidopsis halleri ecotypes.

Hyperaccumulators' ability to take up large quantities of harmful heavy metals from contaminated soils and store them in their foliage makes them promising organisms for bioremediation. Here we demonstrate that some ecotypes of the zinc hyperaccumulator Arabidopsis halleri are more suitable for bioremediation than others, because of their distinct influence on soil biota. In a field experiment, populations originating from metal-polluted and unpolluted soils were transplanted to a highly contaminated metalliferous site in Southern Poland. Effects of plant ecotypes on soil biota were assessed by measurements of feeding activity of soil fauna (bait-lamina test) and catabolic activity and functional diversity of soil bacteria underneath A. halleri plants (Biolog® ECO plates). Chemical soil properties, plant morphological parameters, and zinc concentration in shoots and roots were additionally evaluated. Higher soil fauna feeding activity and higher bacterial community functional diversity were found in soils affected by A. halleri plants originating from metallicolous compared to non-metallicolous ecotypes. Differences in community-level physiological profiles further evidenced changes in microbial communities in response to plant ecotype. These soil characteristics were positively correlated with plant size. No differences in zinc content in shoots and roots, zinc translocation ratio, and plant morphology were observed between metallicolous and non-metallicolous plants. Our results indicate strong associations between A. halleri ecotype and soil microbial community properties. In particular, the improvement of soil biological properties by metallicolous accessions should be further explored to optimize hyperaccumulator-based bioremediation technologies.

The Difference in Zinc Concentrations Required for Induction among Metallothionein Isoforms Can Be Explained by the Different MTF1 Affinities to MREs in Its Promoter

Metallothioneins (MTs) are cysteine-rich low-molecular-weight proteins that protect cells from heavy metal toxicity. MT1 and MT2 are considered ubiquitously expressed among the MT isoforms ranging from 1 to 4. These MT1 and MT2 transcriptions are regulated by metal regulatory transcription factor 1 (MTF1) binding to the metal response element (MRE) of the promoter, which is upregulated in response to zinc. The functional MT isoforms are MT1A, MT1B, MT1E, MT1F, MT1G, MT1H, MT1M, MT1X, and MT2A in humans, but these expressions were differently regulated. Here, MT1A was shown to be significantly less upregulated by zinc than MT1E, MT1G, MT1X, and MT2A. The poor responsiveness of the MT1A zinc was suggested to be due to the MRE sequence in the MT1A promoter region having a lower MTF1 binding affinity compared to the other isoforms. MT1A may be induced via pathways other than the MTF1-MRE binding pathway. These findings may help elucidate the differential regulation of MT isoform expression.

Zinc deficiency is associated with gynecologic cancer recurrence.

Zinc deficiency can cause various symptoms, including hair loss, anemia, and taste disorders. Recently, the association between cancer and zinc deficiency has received much attention with respect to its antioxidant properties. However, only a few studies have investigated the association between gynecologic cancers and zinc; to date, no studies have evaluated serum zinc status at the onset of gynecologic cancer or the relationship between zinc and cancer recurrence. The objectives of the present study were to determine whether serum zinc concentrations are associated with the development of gynecologic cancer, to clarify serum zinc dynamics between the onset and recurrence of gynecologic cancer, and to identify the associated factors. Accordingly, we retrospectively determined serum zinc concentrations before treatment in gynecologic patients with benign disease or cancer at the Nippon Medical School Chiba Hokusoh Hospital. We investigated anemia and hypoalbuminemia-the most common causes of zinc deficiency-as indicators of hyponutrition to determine the causal relationship of this deficiency with chemotherapy, radiation therapy, and recurrence, which may affect zinc concentration during cancer recurrence. The results indicated that there was no difference in zinc concentration between preoperative cancer patients and noncancer patients and that serum zinc concentrations were not associated with developing gynecologic cancers. However, patients with gynecologic cancer exhibited significantly lower serum zinc concentrations following treatment, and patients with recurrent cancer were 4.8 times more likely to develop zinc deficiency than those with nonrecurrent cancer. A serum zinc concentration of <61 μg/dL was an independent predictor of recurrence. Once zinc deficiency occurred, the recurrence rate of zinc deficiency reached as high as 69%. Overall, our study indicates that zinc deficiency is associated with recurrence in gynecological cancers and physicians should monitor zinc levels during disease management.

Hematological and Biochemical Study of Zinc deficiency in Sheep in Fallujah city /Iraq.

The current study was conducted to estimate the Zinc(Zn) levels in serum of (190) Awassi sheep (males) in Fallujah city/ Iraq. The animals were examined clinically and serum samples were examined by atomic absorption spectrophotometer (AAS) to detect the Zn concentration, the results showed decrease in zinc level in addition to significant (P≤0.05) difference between among the control group 0.67±0.42 ppm and affected which include Al-bushegel group0.21±0.42 ppm, Al-falaahat group0.18±0.12 ppm and Al-bualwaan group0.13±0.27 ppm. Also, RBCs reduced in Al-bushegel group6.88±0.51* 106/ul, Al-falaahat group7.03 ± 0.26* 106/ul, and Al-bualwaan group6.37 ± 0.84* 106/ul, thus Hb declined in Al-bushegel group 7.13±0.22g/dl, Al-falaahat group 7.27±0.32g/dl, and Al-bualwaan group 6.82 ± 0.43g/dl in the whole blood samples. PCV was also significant (P≤0.05) reduced in Al-bushegel group 21.41±0.53%, Al-falaahat group 21.75 ± 0.48%, and Al-bualwaan group 20.21 ± 0.15%. On the other hand, the results showed an insignificant difference in MCV among Al-bushegel group 31.1± 0.12fL, Al-falaahat group 30.9± 0.92fL, and Al-bualwaan group 31.7± 0.35fL, but there's no substantial difference in MCHC between Al-bushegel group 33.1±0.21g/dl, Al-falaahat group 33.4±0.54g/dl, and Al-bualwaan group 32.7±0.40g/dl. When compared to control 35.70±2.42 (U/L), there was no significant difference in ALT activity in Al-bushegel group l 31.16 ± 0.19 (U/L), Al-falaahat group 30.60 ± 0.84 (U/L), and Al-bualwaan group 28.22 ± 1.13 (U/L). Furthermore, as compared to control 86.20±18.79 (U/L), AST activity was substantially higher in Al-bushegel group 46.38 ± 1.32 (U/L), Al-falaahat group 42.11 ± 0.82 (U/L), and Albualwaan group 39.48 ± 1.75 (U/L). In this investigation, serum urea levels were 48.09 ± 0.05, 43.00 ± 0.47 and 51.50 ± 0.89 (mg/dl) in Al-bushegel, Al-falaahat, and Al-bualwaan groups respectively, compared to control levels of 22.35±0.11 mg/dl. In comparison to control 0.71±0.04 (mg/dl), serum creatinine levels increased significantly in Al-bushegel group 1.09 ± 0.01 (mg/dl), Al-falaahat group 1.12 ± 0.06 (mg/dl), and Al-bualwaan group 1.14 ± 0.03 (mg/dl). The affected animal group's heart and respiration rates were significantly (P≤0.05) higher than those of the control group. In conclusion, it was a considerable difference in Zinc concentrations, haematological, and biochemical characteristics among sheep studied in Fallujah, Iraq

Determination of Zinc Level of Catfish (Clarias Batrachus) From Sei Sikambing Market by Visible Light Spectrophotometry

Clarias batrachus is one of the commercially cultivated freshwater fish species in Indonesia, especially in North Sumatra. Nutrinya content of protein, fat, minerals, carbohydrates, and water. Minerals play an important role in metabolic processes that ensure the maintenance of body functions at the cellular, tissue and organ levels. The research was aimed at determining the zinc content of raw, steamed, grilled, and fried catfish by using visible light spectrophotometry method after destruction and adding alkaline dithizone solution. Clarias batrachus samples were taken purposively from the traditional market of Sei Sikambing Medan. Method validation includes accuracy, precision, and sensitivity. The results show that it is accurate with accuracy, precision, limit of detection and quantitation of 99.95% each; 1.06%; 0.620 g/ml; 2.066 g/ml. ANOVA test showed no significant difference in zinc content of raw, steamed, grilled, and fried catfish.

Is serum zinc status related to gestational diabetes mellitus? A meta-analysis.

Gestational diabetes mellitus (GDM) is a common medical disorder that begins during pregnancy. The present work aimed to investigate the relationship of maternal or foetal circulatory zinc levels with GDM. Related studies were retrieved against the PubMed/Medline, Web of Science, Scopus databases till July 2020. The overall effects were expressed as standard mean difference (SMD). Furthermore, the random effects model was used to assess the summarised risk ratios (SRRs) to determine the relationship between zinc and the risk of GDM. A total of 15 articles involving were retrieved for meta‐analysis; in the meantime, 4955 subjects including 1549 GDM cases were enrolled for quantitative analysis. Compared with normal control, GDM cases had decreased circulating zinc level on the whole, but the difference was not statistically significant (SMD = −0.40, 95%CI: −0.80 to −0.00, P = 0.05). Interestingly, upon subgroup analysis stratified by serum zinc content but not plasma zinc concentration, there was significant difference in zinc content between GDM cases and normal controls (SMD = −0.56; 95%CI: −1.07 to −0.04, P = 0.03). Meanwhile, subgroup analysis also revealed similar tendency among the Asians and during the 2nd trimester, but not among the Caucasians or during the 1st or 3rd trimester. Data extracted from four studies that compared pregnant women with GDM in the high level of zinc and GDM in the low level of zinc yielded an SRR of 0.929 (95%CI: 0.905–0.954). According to existing evidence, the serum zinc content decreases among GDM cases compared with subjects with no abnormality in glucose tolerance, in particular among the Asians and during the second trimester. Nonetheless, more well designed prospective study should be carried out for understanding the dynamic relationship of zinc level with the incidence of GDM.

Evaluation of anti-nutrient and mineral content in different pearl millet varieties

Pearl millet is one of the most popular crops in India. It is nutritionally comparable and even superior to major cereals with respect to protein, fat, energy, vitamins & minerals. The present investigation was carried out to evaluate the mineral content and the anti-nutrients present in pearl millet varieties i.e., white grain variety (ICMV-221), hybrids varieties (HHB-226, HHB-223 and HHB-197) and HC-20 variety. Calcium content was highest in HHB-226 and lowest in ICMV-221. No significant differences in calcium content of HHB-197 and HHB-223 was witnessed. Significant (P< 0.05) differences in iron content of different varieties of pearl millet were observed. ICMV-221 contained significantly (P< 0.05) higher zinc content than all the other varieties of pearl millet however, no significant difference in zinc content of HC-20 and HHB-223 as well as HHB-197 and HHB-226 were noticed. The phytic acid and polyphenol content of all pearl millet varieties varied from 620.00 to 875.00 and 304.17 to 438.33 mg/100g.

Metallic insignia in primary teeth: A biomarker for Autism Spectrum Disorders.

Lead accumulations have been found in teeth and related to behavior deficits in children, but there is a dearth of studies in exploring the role of zinc and manganese dysregulations in autism spectrum disorders (ASD) using the primary tooth as biomarker. The objectives of the study were to evaluate and compare the concentrations of zinc and manganese in the primary teeth serving as biomarker, in typically developing children and children with ASD. Twelve primary incisors indicated for extraction were collected from children between the age group 6 and 9 years, for the study. Six primary incisors were obtained from children who had been diagnosed with ASD (study group). The other six teeth were obtained from typically developing children, in the similar age group. The primary incisors obtained were analyzed for metal concentrations using the technique Inductively Coupled Plasma Optical Emission Spectrometry. This study was statistically analyzed by student's t-test. It was observed that there are significant differences in metal concentrations found between tooth samples of ASD children and typically developing children. Zinc concentrations were double and manganese concentrations were three times, in teeth of ASD children group as compared to the children in the control group. Results of the current study indicate that there are considerable differences in concentrations of zinc and manganese between the two groups and support the contention that there might be an association between metal exposures of a pregnant mother and child during early years of childhood and incidence of ASD.

IMPORTANCE OF ZINC CONCENTRATION IN SEMINAL FLUID OF MEN DIAGNOSED WITH INFERTILITY.

SUMMARYThe prevalence and importance of male infertility make it a serious worldwide medical and social problem. The aim of this study was to determine if there were any significant differences in zinc concentrations in seminal fluid in men diagnosed with infertility compared to control group, and if there were, to determine how it affected the number and percentage of sperm cells with normal motility and morphology. A case-control study was conducted in the Osijek-Baranja County from January 2014 to June of 2015. The study included 276 subjects referred to biochemistry laboratory of the Osijek University Hospital Centre, 100 (36.2%) of them with low sperm count confirmed by spermiogram after 3 months. Semen samples were processed according to the World Health Organization criteria, and zinc concentrations were determined using spectrophotometry and direct colorimetry without deproteinization on a chemistry analyzer (Olympus AU 680, Beckman Coulter, Tokyo, Japan). Study results showed the men with low sperm count to be significantly older (Mann Whitney U test: p=0.013) and to have lower zinc levels (χ2-test: p<0.001). Further analysis included 100 (36.2%) patients with low sperm count. In the group of infertile men, those with low sperm count had higher zinc levels compared to men with azoospermia (Mann Whitney U test: p=0.036), suggesting a connection between lower zinc level in seminal fluid and male fertility. Zinc as a biological marker and an antioxidant affects sperm count, motility and morphology. Zinc supplemental therapy could improve seminal parameters in patients diagnosed with low sperm count. Dietary habits of the subjects differ regionally, and future research could make a solid foundation for complementary approach to treatment of male infertility.

Efficacy of high zinc biofortified wheat in improvement of micronutrient status, and prevention of morbidity among preschool children and women - a double masked, randomized, controlled trial

BackgroundBiofortification of staple food crops with zinc (Zn) can be one of the cost-effective and sustainable strategies to combat zinc deficiency and prevent morbidity among the target population. Agronomic approaches such as application of Zn fertilizers to soil and/or foliar spray seem to be a practical tool for Zn biofortification of wheat. However, there is a need to evaluate its efficacy from randomized controlled trials. This study aimed to evaluate the efficacy of zinc biofortified wheat flour on zinc status and its impact on morbidity among children aged 4–6 years and non-pregnant non lactating woman of child bearing age (WCBA) in Delhi, India.MethodsIn a community based, double-masked randomized controlled trial, 6005 participants (WCBA and child pairs) were enrolled and randomly allocated to receive either high zinc biofortified wheat flour (HZn, 30 ppm zinc daily) or low zinc biofortified wheat flour (LZn, 20 ppm zinc daily) for 6 months (WCBA @ 360 g/day and children @ 120 g/day). Baseline and endline blood samples were obtained for assessing hematological markers; zinc status and data on compliance and morbidity were collected.ResultsCompliance rates were high; ~ 88% of the WCBAs in both the groups consumed 50% or more of recommended amount of biofortfied wheat flour during the follow up. Similarly 86.9% children in HZn and 87.5% in LZn consumed 50% or more of recommended wheat flour intake. There was no significant difference in mean zinc levels between the groups at end study. This observation might be due to a marginal difference in zinc content (10 ppm) between the HZn and LZn wheat flour, and a short intervention period. However a positive impact of bio-fortification on self-reported morbidity was observed. Compared to children in LZn group, children in HZn group had 17% (95% CI: 6 to 31%, p = 0.05) and 40% (95% CI: 16 to 57%; p = 0.0019) reduction in days with pneumonia and vomiting respectively. WCBA in the HZn group also showed a statistically significant 9% fewer days with fever compared to LZn group.ConclusionsBiofortified wheat flour had a good compliance among children and WCBAs. Significant improvement on some of the self-reported morbidity indicators suggests that evaluating longer-term effects of biofortification with higher grain zinc content would be more appropriate.Trial registrationhttp://ctri.nic.in/Clinicaltrials/, CTRI/2014/04/004527, Registered April 7, 2014.

Characteristics of Soil Physicochemical Properties and Enzyme Activities over Different Reclaimed Years in a Copper Tailings Dam

Mining for metal and mineral resources lead to the rapid rise of tailings dams and caused serious damage to the ecological environment of the mining area. Soil physicochemical characteristics and enzyme activities were important indexes for ecosystem functions, and they were also important factors in evaluating soil restoration qualities. We selected nine sub-dams of the Eighteen River copper tailings in Yuanqu County, and analyzed the relationship between soil physicochemical properties and soil enzyme activities. The results showed that there were great differences in soil physicochemical properties over different reclaimed years, and as the reclaimed years passed, soil nutrient contents significantly increased. There were significant negative correlations between catalase and the ratio of soil carbon and nitrogen, and urease was positively correlated to total nitrogen and soil moisture. Phosphatase and sucrose demonstrated no significant relationships with soil physicochemical factors. Copper content gradually accumulated in soil as the restoration period of sub-dams increased. Arsenic and cadmium content increased initially and then decreased before they gradually reached a stable level. In addition, there was no significant difference in zinc content among different sub-dams. Together, these results provide the ecological basis for further studies in soil ecosystem restoration and degradation mechanisms in copper tailings.

Plasma and saliva levels of three metals in waterpipe smokers: a case control study

In this case-control study, the influence of waterpipe tobacco smoking on the plasma and saliva levels of cadmium, lead and zinc was examined in participants who were waterpipe tobacco smokers (WS) or never-smokers (NS). The concentration of metals was higher in WS relative to NS. The mean (SEM) cadmium concentration in plasma was 3.3 (0.18) µg/dL in WS versus 0.82 (0.09) µg/L in NS (p < .001) and in saliva was 5.1 (0.36) µg/L in WS versus 0.64 (0.2) µg/L in NS (p < .001). The mean (SEM) lead concentration in plasma was 5.2 (0.25) µg/dL in WS versus 3.4 (0.41) µg/dL in NS (p < .01) and in saliva was 4.8 (0.58) µg/L in WS versus 2.8 (0.27) µg/L in NS (p < .05). Similarly, a significant difference in zinc concentration was observed, with a mean of 2.0 (0.17) µg/mL in WS plasma versus 1.49 (0.16) µg/mL in NS (p < .05) and a mean 0.94 (0.07) µg/mL in WS saliva versus 0.45 (0.06) µg/mL in NS (p < .01). In conclusion, waterpipe tobacco smoking is associated with elevated levels of metals in body fluids. These results provide another demonstration of how waterpipe tobacco smoking exposes smokers to harmful toxicants.

Assessment of calcium and zinc accumulation in cultivated and wild apples.

Apple is one of the staple fruits worldwide which are a good source of mineral nutrients. However, little is known about genetic variation for mineral nutrition in apple germplasm. In this study, the calcium and zinc contents in mature fruits of 378 apple cultivars and 39 wild relatives were assessed. Mineral concentrations were quantified using flame atomic absorption spectroscopy (FAAS). Both calcium and zinc accumulation showed great variation among accessions tested. Overall, wild fruits were significantly richer in zinc than cultivated fruits, while the average concentration of calcium was similar between cultivated and wild fruits. The difference in zinc concentration between wild and cultivated fruits may be an indirect result of artificial selection on fruit characteristics during apple domestication. Moreover, calcium concentration in fruit showed a decreasing trend throughout fruit development of apple, while zinc concentration in fruit displayed a complex variation pattern in the late stages of fruit development. The finding of a wild genetic variation for fruit calcium and zinc accumulation in apple germplasm could be helpful for future research on genetic dissection and improvement of calcium and zinc accumulation in apple fruit. © 2017 Society of Chemical Industry.

The serum zinc concentration as a potential biological marker in patients with major depressive disorder

Despite many clinical trials assessing the role of zinc in major depressive disorder (MDD), the conclusions still remain ambiguous. The aim of the present clinical study was to determine and comparison the zinc concentration in the blood of MDD patients (active stage or remission) and healthy volunteers (controls), as well as to discuss its potential clinical usefulness as a biomarker of the disease. In this study 69 patients with current depressive episode, 45 patients in remission and 50 controls were enrolled. The zinc concentration was measured by electrothermal atomic absorption spectrometry (ET AAS). The obtained results revealed, that the zinc concentration in depressed phase were statistically lower than in the healthy volunteers [0.89 vs. 1.06 mg/L, respectively], while the zinc level in patients achieve remission was not significantly different from the controls [1.07 vs. 1.06 mg/L, respectively]. Additionally, among the patients achieve remission a significant differences in zinc concentration between group with and without presence of drug-resistance in the previous episode of depression were observed. Also, patients in remission demonstrated correlation between zinc level and the average number of depressive episodes in the last year. Serum zinc concentration was not dependent on atypical features of depression, presence of psychotic symptoms or melancholic syndrome, age, age of onset or duration of disease, number of episodes in the life time, duration of the episode/remission and severity of depression measured by the Hamilton Rating Scale for Depression (HDRS), and the Montgomery-Asberg Depression Rating Scale (MADRS). Concluding, our findings confirm the correlation between zinc deficit present in the depressive episode, and are consistent with the majority of previous studies. These results may also indicate that serum zinc concentration might be considered as a potential biological marker of MDD.

The hypolipidemic and pleiotropic effects of rosuvastatin are not enhanced by its association with zinc and selenium supplementation in coronary artery disease patients: a double blind randomized controlled study.

ObjectiveStatins treatment may modify the levels of zinc and selenium, minerals that can improve vascular function and reduce oxidative damage and inflammation in atherosclerotic patients. This study aimed to evaluate the effects of rosuvastatin, alone or associated with zinc and selenium supplementation, on lipid profile, antioxidant enzymes and mineral status in coronary artery disease patients.Material and MethodsA double-blind randomized clinical trial was performed in which patients (n = 76) were treated with 10 mg rosuvastatin over 4 months associated or not with zinc (30 mg/d) and selenium (150 μg/d) supplementation. The following parameters were analyzed before and after the intervention: anthropometric measurements, lipid profile, high sensitivity C-reactive protein (hs-CRP), electronegative low density lipoprotein (LDL(-)) concentrations, activities of glutathione peroxidase (GPx), superoxide dismutase (SOD), zinc and selenium concentrations in blood plasma and erythocytes. Significance was determined using an α of 5% (two-tailed).ResultsWe found that rosuvastatin therapy was efficient in reducing total cholesterol, LDL-cholesterol, non-HDL cholesterol, triglycerides, and hs-CRP independently of mineral supplementation. Neither treatment was associated with significant changes in LDL(-). Similarly, the antioxidant enzymes GPx and SOD activity were unchanged by treatments. Neither treatment was associated with significant differences in concentrations of zinc or selenium in blood plasma and erythocytes of studied groups.ConclusionRosuvastatin treatment did not affect zinc and selenium levels in coronary artery disease patients. The zinc and selenium supplementation at doses used in this study did not change lipid profile or SOD and GPx activity in patients receiving rosuvastatin. Further studies should be focused on testing alternative doses and supplements in different populations to contribute for a consensus on the ideal choice of antioxidants to be used as possible complementary therapies in atherosclerotic patients.Trial RegistrationClinicalTrials.gov NCT01547377

Diurnal fluctuation of zinc concentration in metal polluted rivers and its potential impact on water quality and flux estimates

Diurnal fluctuations of metals have been observed in the South Tyne river catchment, UK, in both upland tributaries and major river reaches. Zinc exhibits the most pronounced cyclicity, with concentrations increasing during the night to a maximum near 05:00 before decreasing during the day. This trend is the inverse of pH and temperature observations, which are thought to be the predominant drivers behind the cyclicity. Photosynthetic reactions of biomass and algae alter the pH within the river systems, therefore promoting hydrous metal oxide precipitation during the daylight which consequently allows divalent cations including zinc to sorb onto them. This mechanism may be supported by direct uptake of zinc by algae and other biogeochemical reactions which combine to create large differences in zinc concentrations; during base flow zinc concentrations increased by 326% from the minima over 48 hours. Maximum concentrations are not being captured during routine water quality analysis resulting in inaccurate and misleading EQS results and total flux estimations, for example the annual total zinc flux in a small tributary increases from 17 to 76 tonnes/year when routine grab sample data are supplemented with 24-hour sampling results.

Contamination of Heavy Metals (Lead, Zinc, Magnesium and Manganese) Concentrations in Human Eyes

The aim of our study is to measure the concentration of Lead, Zinc, Magnesium and manganese, toxic/transition metals in human lens. The analyzed samples were categorized according to their personal habits (smoking, food, drinking and medical history). Demographic and laboratory characteristics of patients, the patients were twenty six males and twenty females. The comparison of trace elements between patients and control revealed significant increase of lead and manganese levels in patients and significant decrease of magnesium while there was few significant difference in zinc concentration among them.

Solid-phase reduction of electrofurnace slurry by carbon

In electrosmelting and converter processes, galva� nized scrap from automobiles and other sources is widely used. As a result, smelting is accompanied by considerable release of zinc and iron vapor and their condensation in the dust filters, where oxides of cal� cium, magnesium, and other metals also accumulate. The temperature drop of the metal vapors as they travel in the gaspurification systems determines their condensation and the conversion of the metals to oxides; these processes continue during storage in air. The dust and slurry formed in these conditions contain considerable quantities of iron and zinc. These wastes may provide serve as raw materials in fer� rous and nonferrous metallurgy. The difference in zinc content in converter and electrofurnace slurry is primarily due to the content of galvanized scrap in the batch. As a rule, the zinc con� tent in electrofurnace slurry is considerably higher than in converter slurry. Therefore, it is of most inter� est as a source of zinc. In the present work, we investigate electrofurnace slurry from the Severstal', Serp i Molot, and Elek� trostal' plants. In steel smelting, these plants use vari� ous types of metal scrap: the Severstal' plant largely employs galvanized scrap; the Serp i Molot plant uses a smaller quantity; the Elektrostal' plant mainly employs waste remelting. Study of the slurry composition at these plants shows that the zinc content depends directly on the type of scrap: it is highest at the Severstal' plant, medium at the Serp i Molot plant, and least at the Elektrostal' plant. Table 1 presents the slurry compo� sition. As we see, the largest component in all the slurry is iron (27-37%); the zinc content is low at the Serp i Molot and Elektrostal' plants but rises to almost 17% at the Severstal' plant. Other elements are only present in small quantities. To study the reduction thermodynamics, we need to know not only the elementary composition of the slurry but also its phase composition. To this end, we use Xray phase analysis and gammaresonance (Mossbauer) analysis (1). Xray analysis reveals the presence of oxide phase in the slurry. The Mossbauer data indicate the content of iron in the ironbearing phases. On that basis, tak� ing account of the specific contents of iron and other elements in the slurry (Table 1), we calculate the phase composition of the slurry for all three plants (Table 2).

Heavy metal concentrations in three shorebird species from Okgu Mudflat, Gunsan, Korea

Iron, zinc, copper, lead, and cadmium were measured in livers of three shorebird species from Okgu Mudflat, Korea in the East Asian-Australian migration flyways. Iron concentrations in red-necked stints (Calidris ruficollis) (geomean = 1,322 microg/g dw) were higher than in terek sandpipers (Xenus cinereus) (467 microg/g dw), and great knots (Calidris tenuirostris) (158 microg/g dw). Copper concentrations in great knots (85.8 microg/g dw) were significantly higher than in red-necked stints (15.9 microg/g dw) and terek sandpipers (10.4 microg/g dw). However, significant differences in zinc concentrations were not found in livers among shorebird species. Iron, zinc, and copper concentrations from this study were within the range of other shorebird studies. We suggest that essential elements such as iron, zinc, and copper are within normal range and are maintained there by normal homeostatic mechanism. Lead and cadmium concentrations differed among shorebird species; red-necked stints (geomeans 27.8 microg/g dw and 4.69 microg/g dw, respectively) were higher than in terek sandpipers (12.9 and 0.44 microg/g dw, respectively), and great knots (5.43 and 0.29 microg/g dw, respectively). Some red-necked stints exceeded toxic levels of lead and cadmium for wild birds. In livers of red-necked stints from Okgu Mudflat, lead and cadmium concentrations were higher than previously reported in other shorebirds.