Concentrations Of Essential Trace Metals Research Articles

Changes in the Serum Concentrations of Essential Trace Metals in Patients with Benign and Malignant Breast Cancers.

Essential trace metals (ETMs) may play important roles in the pathophysiology of benign and malignant breast cancers. Our study aimed to find associations between ETMs and benign and malignant breast cancers. We recruited 146 patients with benign (n = 73) and malignant (n = 73) breast tumors and 95 healthy controls (HCs) from Peking University Third Hospital, Beijing, China. The serum concentrations of seven ETMs (Zn, Mn, Cu, Fe, Co, Ni, and Mo) were evaluated using inductively coupled plasma mass spectrometry (ICP-MS). The serum concentrations of Zn were significantly lower in the malignant group than in the HC group, whereas the concentrations of Cu (p < 0.001) were significantly higher in the malignant group. The concentrations of Fe were significantly lower in both malignant and benign groups than in the HC group (p < 0.05). We observed that the Fe/Cu ratio was lower and the Cu/Ni ratio was higher in the malignant group than in the HCs, as well as in the benign group than in the HCs. The serum concentration of Fe (OR = 0.454; 95% CI, 0.263, 0.784; p = 0.005) was negatively associated with breast tumors after adjusting for potential confounders, including age, BMI, and smoking, drinking and menopause statuses; that of Cu (OR = 2.274; 95% CI, 1.282, 4.031; p = 0.005) was positively associated. Changes in the concentrations of ETMs (Zn, Cu, Fe, and Ni) may be involved in the development of malignant breast cancer. The findings provide foundations for further exploration of ETMs in the prevention and treatment of breast tumors.

Use of Dual-Energy CT for Quantification of Essential Trace Metals (Iron, Copper, and Zinc): Proof of Concept.

OBJECTIVE. Altered concentrations of essential trace metals have been associated with the development of abdominal tumors. We developed a method to quantify trace metals (iron, copper, and zinc) using monochromatic data from commercially available dual-energy CT (DECT) implementations. CONCLUSION. Our data provide a foundation for the use of DECT for noninvasive quantification of essential trace metals. Minimum detectable concentrations of iron and zinc estimated with DECT overlap with in vivo hepatic concentrations reported in the literature.

Concentrations of Essential Trace Metals in the Brain of Animal Species-A Comparative Study.

The essential trace metals iron, zinc, and copper have a significant physiological role in healthy brain development and function. Especially zinc is important for neurogenesis, synaptogenesis, synaptic transmission and plasticity, and neurite outgrowth. Given the key role of trace metals in many cellular processes, it is important to maintain adequate levels in the brain. However, the physiological concentration of trace metals, and in particular zinc, in the human and animal brain is not well described so far. For example, little is known about the trace metal content of the brain of animals outside the class of mammals. Here, we report the concentration of iron, zinc, and copper in fresh brain tissue of different model-species of the phyla Chordata (vertebrates (mammals, fish)), Annelida, Arthropoda (insects), and Mollusca (snails), using inductively coupled plasma mass-spectrometry (ICP-MS). Our results show that the trace metals are present in the nervous system of all species and that significant differences can be detected between species of different phyla. We further show that a region-specific distribution of metals within the nervous system already exists in earthworms, hinting at a tightly controlled metal distribution. In line with this, the trace metal content of the brain of different species does not simply correlate with brain size. We conclude that although the functional consequences of the controlled metal homeostasis within the brain of many species remains elusive, trace metal biology may not only play an important role in the nervous system of mammals but across the whole animal kingdom.

Variations in trace metal and aflatoxin content during processing of High Quality Cassava Flour (HQCF)

High Quality Cassava Flour (HQCF) has gained popularity in most parts of West Africa because of its versatility in many industries. However, due to the processing techniques used HQCF may contain trace metals and aflatoxins. Imperatively, the safety of HQCF was assessed when the levels of trace metal and aflatoxin contaminants was determined at the various unit operation during HQCF production. Concentrations of essential trace metals, Cu, Fe and Zn ranged from 0.79 ± 0.09 to1.85 ± 0.26, 10.91 ± 0.44 to 16.64 ± 0.35 and 3.92 ± 0.03 to 10.79 ± 0.16 mg/kg respectively. Toxic trace metals; As and Pb were not detected in any of the samples analysed. The maximum concentration of Hg determined was <0.1 mg/kg. Aflatoxin B1, B2, G1 and G2 were not detected in any of the HQCF samples analysed. The concentrations of As, Cu, Fe, Hg, Pb, and Zn in HQCF were below the limit set by WHO whilst aflatoxin B1, B2, G1 and G2 was not detected in HQCF and therefore pose no public health threat.

English

Diabetes mellitus (DM) &nbsp;has been reported to be associated with derangement of micronutrients. This study was to investigate the plasma levels of antioxidant elements (zinc, selenium, copper) haemopoeitic elements (chromium and iron) and magnesium in female type 2 diabetes mellitus (DM) patients. Fifty (50) female type 2 DM patients (test subjects) aged 20 to 50 years and 35 healthy, non-diabetic age-matched females (control subjects) were recruited for the study. Fasting blood plasma levels of the elements were determined using atomic absorption spectrophotometer (AAS) after acid digestion. Blood glucose level was determined by glucose oxidase/peroxidase method to confirm the status of the test and the control subjects. Body mass index was determined from weight and height of the subjects. The mean values of plasma zinc, selenium, magnesium and chromium were significantly lower in the diabetic patients than in non-diabetics (P&lt;0.002, P&lt;0.001, P&lt; 0.001 and P&lt;0.001 respectively). The mean values of glucose, BMI, iron and copper was observed to be significantly higher in diabetic patients than control subjects (P&lt;0.002, P&lt;0.05, P&lt;0.002 and P&lt;0.001 respectively). A significant positive correlation existed between glucose and BMI, copper and iron (r=0.717; P&lt;0.0001, r=0.717; P&lt;0.05, r=0.721; P&lt;0.05) whereas an inverse relationship was observed between iron and chromium, selenium and magnesium (r =-0.448, -0.703 and -0.651; p&lt;0.004, 0.000, 0.000 respectively). Negative association was also observed between copper and zinc (r=-0.716; P&lt;0.01). These findings revealed that DM is associated with significant alteration in the concentrations of essential trace metals and significant increase in BMI. This may contribute to various metabolic complications and increased mortality from cardiovascular diseases in DM patients in the rural locality as it as observed among diabetics in urban settings. &nbsp; Key words: Trace metals, diabetes mellitus, copper, chromium, Ekiti state.

Predicting Cadmium Accumulation and Toxicity in a Green Alga in the Presence of Varying Essential Element Concentrations Using a Biotic Ligand Model

This study refines the Biotic Ligand Model (BLM) approach by integrating the modulating effects of various essential elements on cadmium (Cd) uptake kinetics in the freshwater alga Chlamydomonas reinhardtii. The algae were first acclimated to a low (LM) or high trace metal (HM) medium as well as to low or high free Cd(2+) and Co(2+) concentrations. The short-term Cd transport capacity and affinity were then quantified in exposure media in which essential trace metals and calcium concentrations were manipulated. The results show that after acclimation to the LM medium, exposure to high free Ca(2+) decreases the capacity of the Cd transport system. Also, acclimation to high (10(-9) M free Co(2+)) or low (10(-11) M free Co(2+)) did not significantly affect Cd uptake rates. When all essential trace metals were simultaneously increased in the acclimation (and exposure) medium, the capacity of the transport system decreased by ∼ 60%, a decrease close to that due to high [Zn(2+)] alone, suggesting that Zn is the main trace metal modulator of the Cd transporter capacity. Changes in Cd toxicity (growth inhibition) in the presence of different essential trace metal concentrations were strongly related to the steady-state concentration of intracellular cadmium, regardless of the cell's nutritional state. Our BLM incorporating the physiological effects of Ca(2+) and other trace metals predicts steady-state Cd accumulation in the presence of varying concentrations of essential elements at 7 nM free Cd(2+), but predictions over a wide range of free [Cd(2+)] proved to be more difficult.

A major quantitative trait locus for increasing cadmium-specific concentration in rice grain is located on the short arm of chromosome 7

Large phenotypic variations in the cadmium (Cd) concentration of rice grains and shoots have been observed. However, the genetic control of Cd accumulation remains poorly understood. Quantitative trait loci (QTLs) determining the grain Cd concentration of rice grown in a Cd-polluted paddy field were identified. Using a mapping population consisting of 85 backcross inbred lines derived from a cross between the low-Cd-accumulating cultivar Sasanishiki (japonica) and high-Cd-accumulating cultivar Habataki (indica), two QTLs for increasing grain Cd concentration were found on chromosomes 2 and 7. A major-effect QTL, qGCd7 (QTL for grain Cd on chromosome 7), was detected on the short arm of chromosome 7. It accounted for 35.5% of all phenotypic variance in backcross inbred lines. qGCd7 was not genetically related to any QTLs for concentrations of essential trace metals (Cu, Fe, Mn, and Zn) or those for agronomic traits such as heading date, suggesting that this QTL is specific to Cd. Furthermore, the existence of qGCd7 was confirmed using chromosome segment substitution lines (CSSLs) and an F2 population from a cross between the target CSSL and Sasanishiki grown in a Cd-polluted paddy soil. To our knowledge, qGCd7 is a novel QTL with major effects for increasing grain Cd concentrations.

Extracellular matrix and culture substratum effects on trace metal content of epithelial cancer cells

The effect of extracellular adhesion factors, and of distinct culture substrata, on trace element content of epithelial cancer cells was investigated using nuclear microprobe analysis. Essential trace metal concentrations in human carcinoma cells cultured either onto tissue culture plastic dishes, onto microanalysis supports made of thin Formvar surfaces coated or not with gelatin gel, or onto polycarbonate films, were compared. Abnormally high copper concentrations were noticed specifically in cisplatin-resistant epithelial cancer cells cultured onto Formvar or polycarbonate surfaces with or without reconstituted extracellular matrix. Manganese, iron and zinc concentrations remained unchanged in these cells. These results indicate that (1) metal uptake of cells cultured onto substrata used for X-ray microanalysis can be different to that of cells cultured onto usual plastic dishes, (2) cisplatin-resistant epithelial cancer cells specifically accumulate copper when cultured onto thin Formvar or polycarbonate films, and could be used as in vitro models for copper overload studies.

Zinc supplementation does not prevent cuprizone toxicity in the brain of mice

The metal ion chelator cuprizone (bis(cyclohexanone)oxalyldihydrazone) is an effective agent for inducing experimental demyelination in rodents. The current work was undertaken to assess whether this demyelination was a result of the ability of cuprizone to sequester metal ions thereby leading to a reduction of tissue concentrations of essential trace metals. After cuprizone administration, demyelination in mouse brain was followed using biochemical techniques and it was shown that mice fed cuprizone for 49 days had reduced blood concentrations of copper, zinc and iron but that the brain contents of these cations were not decreased. Also, that loss of carbonic anhydrase activity (CAII)(a zinc metalloenzyme) in cuprizone fed mice could not be prevented by the feeding of a zinc supplemented diet. Indeed, zinc supplementation itself had an deletrious effect on kidney CA11 activity. The findings are discussed in relation to possible roles for CA in the CNS and kidney.

Some toxic and trace metals in big game hunted in the northern part of Poland in 1987–1991

Game animal meats (muscle, liver and kidneys) collected from different regions in northern part of Poland in 1987–1991 were analysed for mercury, cadmium, lead, copper, manganese, zinc and iron. Toxic mercury, cadmium and lead occured in relatively low concentrations in muscle and organ meats, with the exception of lead in muscle and cadmium in kidneys, which were relatively more contaminated. The concentrations of essential trace metals in samples examined seemed to be natural. Roe-deer contained relatively higher concentrations of copper, both in liver and kidneys, than stag and wild boar, while stag had higher levels of manganese in muscle meat and organs. The weighted mean concentration ranges obtained related to wet-weight for muscle, liver and kidneys of wild boar, roe-deer and stag were 1.2–3.4, 7.3–15, and 24–54 μg/kg for mercury; 10–10, 110–210, and 1500–2100 μg/kg for cadmium; 86–160, 190–210, and 210–290 μg/kg for lead; 1.6 and 1.8, 4.5–28, and 5.4–12 mg/kg for copper; 0.24–0.83, 1.7–5.2, and 1.3–4.1 mg/kg for manganese; 32–37, 37–47, and 30–48 mg/kg for zinc; and 24–31, 40–54, and 67–83 mg/kg for iron, respectively. Single specimens of elk and aurochs were examined also. From the point of view of health, contamination of muscle with lead, as a result of shot pellet fragmentation, and of kidneys with cadmium from the contaminated environment, seemed to be of greatest concern. The values obtained were compared with the available literature data.

Distribution of Trace Metals within the Aboveground Phytomass of Acer saccharum Marsh, and Betula alleghaniensis Britt. at the Turkey Lakes Watershed

A study of Mn, Fe, Zn, Cu, Pb, Ni, and Cd distribution in Acer saccharum Marsh, (sugar maple) and Betula alleghaniensis Britt. (yellow birch) was carried out at the Turkey Lakes Watershed (TLW) in the District of Algoma, Ontario. Aboveground phytomass was dominated by stemwood (134 200 kg∙ha−1), stembark (19 300 kg∙ha−1), and branches &gt; 2 cm (38 800 kg∙ha−1). Acer saccharum was the dominant species, accounting for 88% of the aboveground phytomass. The generalized phytomass trace metal concentration series for A. saccharum was Mn &gt; Fe &gt; Zn &gt; Cu &gt; Pb &gt; Ni &gt; Cd and for B. alleghaniensis was Mn &gt; Zn &gt; Fe &gt; Cu &gt; Pb &gt; Ni &gt; Cd. Concentrations of metals were highest in the foliage or stembark and lowest in stemwood but, because of its large mass, stemwood generally contained the greatest amount of metal per tree and per hectare. Components of B. alleghaniensis contained higher Zn and Cd concentrations than did those of A. saccharum by a factor of between 4 and 10, an indication that B. alleghaniensis is an accumulator of these metals. Lead levels in all components were one-third to one-half those reported elsewhere, a reflection of lower deposition at TLW. Historical data from other sites in North America gave no indication that concentrations of essential trace metals in aboveground components were higher than normal for these species.

Trace element distribution within the tree phytomass and forest floor of a tolerant hardwood stand, Algoma, Ontario

An examination of tree phytomass and trace metal concentrations (w/w) and pools in the tree stratum and forest floor of a sugar maple-yellow birch forest was carried out at Turkey Lakes Watershed, Algoma District, Ontario. Estimated aboveground tree phytomass (167, 500 kg ha−1) was dominated by stemwood, branches > 2 cm, and stem bark. Highest trace metal concentrations were found in foliage (Cu, Fe, Mn, Ni) and stem bark (Cd, Pb, Zn). Concentrations of essential trace metals found in all sugar maple components followed the expected sequence of Mn>Fe>Zn>Cu. Lead and Ni concentations were always higher than those of Cd. Concentrations of essential elements in foliage and other components were comparable to those reported in the literature for other localities in North America. There was no indication that availability of essential trace elements (e.g., Cu) to vegetation had been increased as a result of increased atmospheric deposition. Lead, Ni and Cd levels in vegetation and forest floor were lower than those reported for similar forested areas of the northeastern United States.

REMOVAL OF TRACE METALS FROM MARINE CULTURE MEDIA

The sodium form of purified Chelex‐100 can be used to remove trace metals from artificial and natural seawater without altering the major cation‐anion composition or contributing organic toxicants or chelators. Specific contaminant trace metals, often present in artificial seawater at toxic levels, are reduced to levels that permit the growth of sensitive marine phytoplankton and the development of certain invertebrates from the egg through early larval stages. The concentrations of essential trace metals are reduced below the nutritional requirements of selected species of marine phytoplankton.