Levels of dinoflagellate chromosome-bound metals in conditions of low external ion availability: An X-ray microanalytical study

Cells of the dinoflagellate Glenodinium foliaceum were able to grow and divide in artificial (AE50) liquid culture medium diluted down to 10% of its normal concentration. X-ray microanalysis, with on-line computation of mass fractions, was used to determine the quantitative occurrence of bound (insoluble) elements in the chromosomes of cells grown in normal, 30 and 10 % medium. In normal medium, chromosomes contained high levels of phosphorus (nucleic acid), sulphur (protein) and a variety of bound divalent metals, including Ca, Fe, Ni, Cu and Zn. With a decrease in the level of external ions (30 and 10% dilutions), the level of sulphur showed a significant decrease, but the mass fractions of insoluble phosphorus and total divalent metals did not fall. The presence of these metals in dinoflagellate chromatin does not, therefore, simply involve intracellular deposition in response to high external levels. The occurrence of divalent metals showed variation with medium concentration in terms of the proportions of different metals present, the nature of the metal-nucleoprotein associations, the metal concentrations per unit mass of chromatin and the number of metal atoms per 100 nucleotides. None of the above characteristics is therefore constant in an individual species.     

Interactions between toxic (As, Cd, Hg and Pb) and nutritional essential (Ca, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, Zn) elements in the tissues of cattle from NW Spain

Since the toxicity of one metal or metalloid can be dramatically modulated by the interaction with other toxic or essential metals, studies addressing the chemical interactions between trace elements are increasingly important. In this study correlations between the main toxic (As, Cd, Hg and Pb) and nutritional essential (Ca, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, Zn) elements were evaluated in the tissues (liver, kidney and muscle) of 120 cattle from NW Spain, using Spearman rank correlation analysis based on analytical data obtained by ICP-AES. Although accumulation of toxic elements in cattle in this study is very low and trace essential metals are generally within the adequate ranges, there were significant associations between toxic and essential metals. Cd was positively correlated with most of the essential metals in the kidney, and with Ca, Co and Zn in the liver. Pb was significantly correlated with Co and Cu in the liver. A large number of significant associations between essential metals were found in the different tissues, these correlations being very strong between Ca, Cu, Fe, Mn, Mo and Zn in the kidney. Co was moderately correlated with most of the essential metals in the liver. In general, interactions between trace elements in this study were similar to those found in polluted areas or in experimental studies in animals receiving diets containing high levels of toxic metals or inadequate levels of nutritional essential elements. These interactions probably indicate that mineral balance in the body is regulated by important homeostatic mechanisms in which toxic elements compete with the essential metals, even at low levels of metal exposure. The knowledge of these correlations may be essential to understand the kinetic interactions of metals and their implications in the trace metal metabolism.     

X-ray microanalysis of unfixed chromatin in dinoflagellate cells prepared by a monolayer cryotechnique

The fine structural appearance and elemental composition of unfixed chromatin is described for cells of the dinoflagellate Prorocentru micans prepared by a freeze-drying technique. This involves rapid freezing, cryo-dehydration and resin infiltration of a monolayer of cells dispersed over a resin base.The fine structure of the nucleus appears quite different from chemically fixed and dehydrated cells. In stained sections, the chromosomes are seen as pale areas containing diffuse chromatin, and are surrounded by electron-dense nucleoplasm which has a reticulate substructure.X-ray microanalysis reveals the presence of high levels of chromatin-associated Ca and transition metals Fe, Ni, Cu and Zn, in accordance with previous observations on chemically processed cells. Calculation of elemental mass fractions by on-line computer demonstrates an overall ratio of one divalent cation per two phosphorus groups (or per two nucleotides). This ratio is similar to that obtained previously for chemically fixed chromatin, and shows that the precise overall association of metals is not primarily determined by the process of fixation.     

Toxic and Essential Mineral Elements Content of Black Tea Leaves and Their Tea Infusions Consumed in Iran

The metal contents of eleven black tea samples, four cultivated in Iran and seven imported, and their tea infusions were determined. Twelve elements consisting toxic metals (Al, As, Pb, Cr, Cd, and Ni) and essential mineral elements (Fe, Zn, Cu, Mn, Ca, and Mg) were analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES). Al, Ca, Mg, and Mn ranged in black tea leaves at mg g⁻¹ levels, while Cr, Fe, Ni, Cu, Zn were at μg g⁻¹ levels. Analysis of variance showed no statistically significant differences among most elements determined in cultivated and imported black teas in Iran except for Ni and Cu. The extraction efficiency of each element into tea infusions was evaluated. The solubility of measured metals in infusion extracts varied widely and ranged from 0 to 59.3%. Among the studied elements, Cr, Pb, and Cd showed the lowest rates of solubility and Ni had the highest rates of solubility. The amount of toxic metals and essential mineral elements that one may take up through consumption of black tea infusion was estimated. The amount of realizing each element into tea infusions and acceptable daily intake, for safety consumption of black tea, was compared.     

Localised uptake of63nickel into dinoflagellate chromosomes: An autoradiographic study

Summary The uptake of⁶³Ni into cells of the binucleate dinoflagellateGlenodinium foliaceum was investigated using insoluble compound light and electron microscope autoradiography. Cells labelled over a period of 2 hours showed active uptake throughout the whole population, with an increase in mean cell grain count when the labelling period was extended to 4 hours and 24 hours. The mean grain count did not vary with type of fixation (glutaraldehyde, paraformaldehyde or acetic alcohol) suggesting that retention of⁶³ Ni is not a specific fixation-binding artefact. At light microscope level, silver grains were not localised to any major cell component, but with the greater resolution of electron microscope autoradiography, a high degree of localisation was demonstrated in the typical dinoflagellate (dinocaryotic) nucleus-which contained about 83% of the cell label (cytoplasm 16%, supernumerary nucleus 1%). Silver grain distribution within the dinocaryotic nucleus was consistent with some degree of localisation to the condensed chromatin.The autoradiographic results corroborate previous X-ray microanalytical data which demonstrated high levels of transition metals in dinoflagellate nuclei. The distinction between the two types of nucleus inGlenodinium is further emphasised, giving additional support to the concept of a separate phyllogenetic origin of the supernumerary nucleus.     

Metal metabolism in the red alga Cyanidium caldarium and its relationship to metal tolerance

The unicellular red alga Cyanidium caldarium is tolerant to high levels of various metal ions. Cells of this alga cultured with divalent metal ions at 5 mM contained an elevated concentration of each metal, with the highest level for Zn followed by Mn > Ni > Cu. This order is in fair agreement with the toxicity levels reported previously, with the exception of Mn, which shows a toxicity level comparable to that of Ni. Transmission electron microscopy indicated the presence of electron-dense bodies in the algal cells, and elemental analysis by energy dispersive X-ray spectrometry showed high levels of Fe and P in these bodies. Accumulation of Zn was found in these particles in Zn-treated algal cells, whereas no such deposition was found for Cu, Ni, or Mn in cells treated with the respective metals. Although trapping of Zn in the intracellular bodies may contribute to reduction of metal activity in the cells, this effect can be overcome by high intracellular levels of Zn that result in a high degree of toxicity. The correlation between intracellular concentration and toxic levels of metal ions implies that the reduced incorporation of the metals is a major detoxification mechanism in this alga.     

浙江油茶产地土壤和果实金属元素含量特征

为探讨油茶(Camellia oleifera)产地土壤和油茶果实中金属元素分布和富集特征,在油茶果实成熟期,对浙江5个油茶产地土壤及油茶果实中金属元素进行污染分析和富集能力评价.结果表明,浙江油茶产地土壤中Pb、Cr、Cd、As、Hg、Ni、Cu和Zn含量低于农用地土壤污染风险筛选值,综合污染等级为安全.个别产区常山...     

The occurrence of metals Al, Fe, Ni, Cu, Zn in the nuclei of animal cells: an ultrastructural, in situ, X-ray microanalytical study

Cell nuclei may contain significant quantities of the metals Fe, Ni, Cu, Zn, since they are present in the nucleo-enzymes and/or nucleic acids. These metals have been detected by X-ray microanalysis in situ in dinoflagellates (Kearns et al). Aluminum was only detected in cell nuclei in cases of natural or provoked intoxication. We observed at the ultrastructural level, in situ, the presence of Al, Fe, Ni, Cu, Zn in nuclei of different types of non-intoxicated animal cells. Moreover, we measured the concentration of these metals in the nucleolus and chromatin and compared it with the concentration of P and S.     

Screening of Trace Metals in the Plasma of Breast Cancer Patients in Comparison with a Healthy Population

The plasmas of breast cancer patients and healthy donors were analyzed for selected trace metals by a flame atomic absorption spectrophotometric method. In the plasma of breast cancer patients, mean concentrations of macronutrients/essential metals, Na, K, Ca, Mg, Fe, and Zn were 3584, 197.0, 30.80, 6.740, 5.266, and 6.170 ppm, respectively, while the mean metal levels in the plasma of healthy donors were 3908, 151.0, 72.40, 17.70, 6.613, and 2.461 ppm, respectively. Average concentrations of Cd, Cr, Cu, Mn, Ni, Pb, Sb, Sr, and Zn were noted to be significantly higher in the plasma of breast cancer patients compared with healthy donors. Very strong mutual correlations (r > 0.70) in the plasma of breast cancer patients were observed between Cd–Pb, Cr–Li, Li–K, Li–Cd, K–Cr, Li–Pb, Cr–Co, Cu–Ni, Co–K, Cd–K, and K–Pb, whereas, Al–Cr, Ca–Zn, Cd–Sb, Cd–Zn, Ca–Mg, Fe–Zn, and Na–Mn exhibited strong relationships (r > 0.60) in the plasma of healthy donors. The cluster analysis revealed considerably different apportionment of trace metals in the two groups of donors. The average metal concentrations of different age groups of the two donor categories were also evaluated, which showed the build-up of Al, Cd, Co, Cr, Mn, Li, Pb, Sb, and Zn in the plasma of breast cancer patients. The role of some trace metals in carcinogenesis is also discussed. The study indicated appreciably different patterns of metal distribution and correlation in the plasma of breast cancer patients in comparison with the healthy population.     

Fas- and Mitochondria-Mediated Signaling Pathway Involved in Osteoblast Apoptosis Induced by AlCl<Subscript>3</Subscript>

The concentrations of 13 elements (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn) were determined in several samples of native (wild) naturally growing and cultivated blueberry fruits. The total metal contents after mineralization were analyzed by inductively coupled plasma optical emission spectrometry. Reliability of the procedure was checked by the analysis of the certified reference materials Mixed Polish Herbs (INGT-MPH-2) and Leaves of Poplar (NCS DC 73350). In the fruits collected in the forest (wild blueberries), higher contents of Ca, Na, and Mg as well as Mn and Zn were observed. Similar levels of Cu, Cr, Fe, and Ni were detected in both wild-growing and cultivated plants. The significantly higher content of Fe and Cd in cultivated blueberries was connected with the content of these metals in soil samples collected from the same places. The metal extraction efficiency by hot water varied widely for the different blueberries (wild or cultivated) as well as their form (fresh or dried).     

Effects of six trace metals on calcium fluxes in brown trout (Salmo trutta L.) in soft water

Summary Calcium fluxes were measured simultaneously in brown trout fry maintained in an artificial soft water medium of [Ca] 20 mol·l^-1 and pH 5.6, and exposed to each of six trace metals (Al, Cu, Fe, Ni, Pb, and Zn). The trace metal concentrations represented typical and maximum levels found in acid waters experiencing declining fishery status. In the absence of trace metals, evidence is presented which suggests that ca. 91% of Ca taken up from the external medium was by extraintestinal active transport. Calcium efflux was stimulated by both concentrations of Al, Cu, Fe, and Pb. Efflux was also stimulated by [Ni] 170 nmol·l^-1 and [Zn] 3000 nmol·l^-1. In some cases, response to increased efflux was stimulation of influx. Lack of stimulation of influx resulted in negative net Ca fluxes. Net Ca losses were recorded at both concentrations of Al, Pb, and Ni, lower concentrations only of Fe, and higher concentrations only of Cu and Zn.Abbreviations J _in influx - J _net net flux - J _out efflux Henceforward in this paper, chemical elements are referred to by their chemical symbols rather than by full names     

Comparative Evaluation of Trace Metal Distribution and Correlation in Human Malignant and Benign Breast Tissues

Selected trace metals were analyzed in human malignant and nonmalignant (benign) breast tissue samples by the flame atomic absorption spectrophotometric method. In malignant tissues, dominant mean concentrations were revealed by Na, K, Ca, Mg, Fe, Zn, and Al at 927, 552, 231, 61.7, 36.5, 18.3, and 8.94 microg/g, respectively, while the mean metal levels in benign tissues were 903, 435, 183, 63.3, 24.7, 14.5, and 10.1 microg/g, respectively. Average concentrations of Cd, Co, Cr, Cu, Fe, Mn, K, Ca, and Zn were noted to be significantly higher in the malignant tissues compared with the benign tissues. Significantly strong correlations (r > 0.50) in malignant tissues were observed between Mn and Co, Mn and Cd, Cd and Cr, Fe and Mn, Cd and Co, Fe and Co, Mg and Pb, Cd and Fe, Mg and Ni, Pb and Ni, Ni and Sr, and Fe and Pb, whereas, Cd and Co, Cd and Mn, Co and Mg, Co and Mn, Cu and Mn, Co and Ni, Mg and Ni, Cd and Cu, Cd and Ni, Ca and Mg, Mn and Pb, Cu and Ni, Fe and Ni, Cd and Mg, Co and Cu, Cr and Na, and Cd and Cr revealed strong and significant relationships in benign tissues at p < 0.001. Principal component analysis of the metals data yielded six principal components for malignant tissues and five principal components for benign tissues, with considerably different loadings, duly supported by cluster analysis. The study revealed a considerably different pattern of distribution and mutual correlations of trace metals in the breast tissues of benign and cancerous patients.     

Metals in proteins: cluster analysis studies

We have conducted a prospective analysis of the Protein Data Bank in order to study certain constituents of proteins: elements that are neither halogens nor phosphorus nor part of the biological amino acid set. A sample of 5749 structures was analyzed and classified according to the 56 elements encountered. Fifteen metals (Na, Mg, K, Ca, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, W, Hg) are involved in almost half of the structures, with each metal figuring in more than 100 structures. We analyzed this subsample in more detail by computing the amino acid residues occurring within a coordination sphere of 5 Å centered on the element, and using methods of cluster analysis to group the elements. The analyses undertaken here are able to distinguish between real components of proteins and elements inserted by artefacts of the crystallization process or experimental techniques.     

四种金花茶组植物叶片金属元素含量及富集特性研究

以四种金花茶组植物为研究对象,采用原子吸收光谱法和原子荧光法,测定其嫩叶、老叶及对应土壤中Mg、Ca、Mn、Fe、Zn、Ni、Se、Pb、Cd、Hg、As共11种元素的含量,并分别计算嫩叶和老叶对土壤金属元素的富集系数.结果表明:(1)4种金花茶组植物叶片富含Mg、Ga、Mn、Fe、Zn、Ni等营养元素,各元素在叶片中含量为Ca>Mg>Mn>Fe>Zn>Ni>Se;Pb、Cd、As、Hg等重金属元素含量较低,均达到无公害茶叶标准.(2)老叶和嫩叶中各金属元素含量差异较大,老叶中的Ca、Mn、Fe、Zn、Pb、Cd、Hg、As、Se元素含量均大于嫩叶,尤以Ca、Mn、Fe差异显著;嫩叶中的Mg和Ni含量大于老叶.(3)金花茶组植物对不同金属元素的富集能力不同,对各元素富集能力强弱为Ca、Mn、Mg>Zn、Ni、Hg>Pb、Se>Fe、As,老叶和嫩叶的富集规律存在差异.(4)不同金花茶组植物对金属元素的富集能力有较大差异,龙州金花茶(Camellia longzhouensis)和黄花抱茎茶(C.murauchii)对Mg、Ca、Mn、Zn、Ni、Se、Pb的富集能力均大于金花茶(C.nitidissima)和毛籽金花茶(C.ptilosperma).其中,龙州金花茶对Mg、Mn、Se的富集能力最强,黄花抱茎茶对Ca、Pb、Hg富集能力最强,金花茶对Hg的富集能力较强,对其它元素的富集能力均较弱;毛籽金花茶对Ca、Mn、Ni、Zn的富集能力均最弱.该研究结果为金花茶组植物的进一步开发和利用提供了理论依据.     

Transfer of selected mineral nutrients and trace elements in the host–hemiparasite association, Cistus–Odontites lutea, growing on and off metal-polluted sites

The role of a hemiparasitic life-style in plant resistance to toxic trace elements in polluted soils is unclear. Restriction of metal uptake by the host, restriction of metal transfer from host to parasite, or transformation of metals into a less toxic form may play a role. This study analysed the transfer of selected mineral elements from soil to host ( Cistus spp . ) and from host to hemiparasite ( Odontites lutea) at locations with different metal burdens: a Cu-rich serpentine site, Pb–Ba mine spoil and an unpolluted soil. Highest soil-to-host transfer factors for K, Mg, Ca, Zn, Cu and Pb were observed on the unpolluted soil. Statistically significant differences among locations of host-to-parasite transfer factors were only found for Ca and Pb. Restriction of transfer of unfavourable Ca/Mg ratios, characteristic at the serpentine site, and of high Pb and Zn concentrations at the Pb–Ba mine occurred mainly at the soil–host, and not at the host–parasite, level. Odontites lutea was able to withstand enhanced Zn and Pb concentrations and low Fe/Cu ratios in shoot tissue without developing toxicity symptoms. This could be caused by specific metal resistance mechanisms in this hemiparasite and/or the transformation and transfer of these metals into a less toxic form by the metal-tolerant host.     

Comparative Evaluation of Trace Metals in the Blood of Hepatitis C Patients and Healthy Donors

Hepatitis C is one of the common types of chronic liver disease, and its plausible association with trace metal imbalance has been investigated in the present study. The blood samples of hepatitis C patients and healthy donors were analysed for trace metals (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, and Zn) by flame atomic absorption spectrophotometry after wet acid digestion. In the blood of the hepatitis patients, mean concentrations of essential metals, Na, K, Fe, Ca, Mg, and Zn, were 918.7, 361.0, 102.5, 20.00, 24.66, and 9.429 ppm, respectively, while the mean metal levels in the blood of healthy donors were 1509, 406.8, 232.5, 28.35, 24.59, and 8.799 ppm, respectively. On the average, Cr was significantly higher, while Na, Fe, Ca, Cu, Mn, Pb, and Cd were comparatively lower in the blood of the patients. The correlation study manifested significantly divergent mutual relationships of trace metals in the blood of the patients and healthy donors. Multivariate statistical methods revealed considerably diverse distribution of trace metals in the two groups. Dissimilarity in the trace metal distribution was also noted with the gender and residential location of the donors in both groups.     

Study of the age and sex dependence of trace elements in hair by correspondence analysis

The aim of the study was to examine the potential of multidimensional analysis, and in particular of correspondence analysis (CA), in bringing to light the influence of sex and age on trace element (TE) concentrations in hair from an unselected French population. Sixteen elements (S, Hg, Se, Zn, Pb, Cd, Ni, Co, Mn, Fe, Cr, Mg, Al, Ca, Cu, Ag) were assayed by inductively coupled argon plasma (ICAP) emission specrroscopy in the scalp hair of 135 men and 346 women. In spite of the high background noise, CA was able to reveal the differing patterns in males and females. For instance, in this population, higher relative levels of the essential elements, Ca, Mg, Zn, and Cu, but also of Ag, characterized women’s hair, whereas higher relative levels of the heavy metals, Fe and Pb, were associated with men’s hair. Al and Ag were unexplainedly high in the hair of the youngest members of the population. The Cu and Co of youth seemed to give way to a predominance of Zn in maturity. The hair of individuals in their forties tended to be richest in Ca and Mg, but these elements decreased with advancing age. Heavy metals (Hg, Pb, Fe) accumulated with age, whereas Se, Mn, and Cr seemed independent of age. CA is manifestly a very useful tool for revealing underlying dimensions in complex dynamic systems and unsuspected relationships among variables. Clearly, the significance of the high Al and Ag contents in the hair of certain members of the population, especially of the very young, needs to be investigated from both physiological and toxicological aspects.     

Comparative Assessment of Selected Metals in the Scalp Hair and Nails of Lung Cancer Patients and Controls

Lung cancer is seriously threatening human health and exposure to trace metals is the most important aetiology for lung cancer. Selected essential/toxic metals (Ca, Mg, Na, K, Fe, Zn, Cu, Sr, Li, Co, Mn, Ni, Cr, Cd and Pb) are measured in the scalp hair and nails of lung cancer patients and controls by atomic absorption spectrophotometric method employing nitric acid-perchloric acid-based wet digestion. Average concentrations of Pb, Cd, Mn, Co and Cu are found to be significantly higher (p?<?0.05) in the scalp hair and nails of lung cancer patients compared with the controls, however, appreciably higher concentrations of Zn, Ca, Na, Mg and Cr are noted in the scalp hair of the controls. Most of the metal levels reveal higher dispersion and asymmetry in the scalp hair/nails of the patients compared with the controls. Average metal levels are also compared to investigate probable differences based on sex, abode, food and smoking habits. The correlation study shows significantly diverse mutual variations of the metals in the scalp hair and nails of the patients and controls. Considerable variations in the metal levels are also noted for various stages and types of lung cancer (adenocarcinoma, squamous cell carcinoma, large cell carcinoma and small cell lung cancer). Multivariate apportionment of the metals in the scalp hair and nails of the patients and controls are also significantly diverse. The study reveals considerably divergent variations in the metal levels in lung cancer patients in comparison with healthy subjects.     

Accumulation of metals and metalloids in radish (Raphanus sativus L.) and spinach (Spinacea oleracea L.) irrigated with domestic wastewater in the peri-urban areas of Khushab City,Pakistan

Accumulation of different metals and metalloids was assessed in two vegetables radish (Raphanus sativus L.) and spinach (Spinacea oleracea L.) irrigated with domestic wastewater in the peri-urban areas of Khushab City, Pakistan. In general, the metal and metalloid concentrations in radish and spinach were higher at site-II treated with sewage water than those found at site-I treated with canal water. In case of radish at both sites the levels of metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, and Pb) were below the permissible level except those of Mn, Ni, Mo, Cd, and Pb. At both sites, the transfer factor ranged from 0.047–228.3 mg kg^?1 with Cr having the highest transfer factor. The metal pollution index in soil was in the following order: As > Fe > Ni > Zn > Cd > Mo > Se > Co > Pb > Mn > Cr > Cu, respectively. While in case of spinach at both sites, the concentrations of metals and metalloids in vegetable samples irrigated with canal and sewage water were observed below the permissible level except Mn, Ni, Zn, Mo, and Pb. At both sites, the transfer factor ranged from 0.038–245.4 mg kg^?1 with Cr having the highest transfer factor. The metal pollution index in soil was in the following order: Cd > Ni > Co > Se > Mn > Zn > Mo > Pb > Fe > Cr > As > Cu, respectively.     

珠江口桂山岛表层沉积物中重金属的分布特征及潜在生态危害评价

于2011年8月采集了珠江口桂山岛海域12个站点的表层沉积物, 对沉积物中重金属的含量进行了测定。结果表明, 桂山岛沉积物中重金属含量与国内外港湾相比属于中等水平, Pb、Cr、Ni、Cu、Zn、Mn平均含量分别为40.06、31.29、14.17、30.67、100.18、599.76 mg/kg。富集系数法和 Hakanson潜在生态风险指数法评价表明:桂山岛沉积物各重金属元素的富集顺序为Cu﹥Pb﹥Zn﹥Mn﹥Cr﹥Ni, 其中Cu、Pb、Zn和Mn富集系数大于1;该海域重金属潜在生态风险总体上处于低水平, 从空间上看, S11危害最为严重。进一步通过主成分分析研究沉积物中重金属的来源, 发现前2个主成分贡献率分别为44.38%、42.61%, 表明重金属主要有2个来源:工业和生活污水排放、岩石的自然风化与侵蚀过程。