Evaluation of potentially toxic elements in soils developed on limestone and lead-zinc mine sites in parts of southeastern Nigeria.

The present study investigated the distribution of elements and potentially toxic elements (PTEs) in soil profiles in the southeastern region of Nigeria, where unrefined and primitive mining practices are common. Soil samples were collected from mine and non-mine sites in Ameka and Nkalagu and analyzed for total elemental concentration using portable X-ray fluorescence (pXRF). The results showed that the Ameka mine-affected soils were heavily polluted, while the Ameka non-mine-affected soils were moderately polluted.

Using an ensemble model coupled with portable X-ray fluorescence and visible near-infrared spectroscopy to explore the viability of mapping and estimating arsenic in an agricultural soil.

Increasing concentrations of potentially toxic elements (PTE) in agricultural soils remain a major source of public concern. Monitoring PTEs in an agricultural field with no history of contaminants necessitate adequate analysis utilizing a robust model to accurately uncover hidden PTEs. Detecting and mapping the distribution of soil properties using portable X-ray fluorescence (pXRF) and proximal sensing techniques is not only rapid, but also relatively inexpensive.

An in-depth human health risk assessment of potentially toxic elements in highly polluted riverine soils, Příbram (Czech Republic).

Environmental pollution by potentially toxic element (PTE) and the associated health risks in humans are increasingly becoming a global challenge. The current study is an in-depth assessment of PTEs including the often studied lead (Pb), manganese (Mn), zinc (Zn), arsenic (As) and the less-studied titanium (Ti), rubidium (Rb), strontium (Sr), zirconium (Zr), barium (Ba) and thorium (Th) in highly polluted floodplain topsoil samples from the Litavka River, Czech Republic. Soil chemical properties including carbon (C) and reaction (pH_HO) together with iron (Fe) were assessed in the same soils.

The influence of land-use on tropical soil chemical characteristics with emphasis on aluminium.

Composition of soil vegetation cover and land management directly influences the cycling of chemical elements and is a key factor for soil biogeochemistry and also Al behaviour. Moreover, Al is an important factor limiting the growth of cultural plants. Our results are based on long-term observations of soils translocated from selected small areas of eight 1 ha plots of different land-use gradient, with identical geological, climatic and geographical conditions, located in the North of Congo Basin (near Mbalmayo, Cameroon).

Isotopic Tracing of Thallium Contamination in Soils Affected by Emissions from Coal-Fired Power Plants.

Here, for the first time, we report the thallium (Tl) isotope record in moderately contaminated soils with contrasting land management (forest and meadow soils), which have been affected by emissions from coal-fired power plants. Our findings clearly demonstrate that Tl of anthropogenic (high-temperature) origin with light isotope composition was deposited onto the studied soils, where heavier Tl (ε(205)Tl ∼ -1) naturally occurs. The results show a positive linear relationship (R(2) = 0.

The variations of aluminium species in mountainous forest soils and its implications to soil acidification.

Aluminium (Al) speciation is a characteristic that can be used as a tool for describing the soil acidification process. The question that was answered is how tree species (beech vs spruce) and type of soil horizon affect Al speciation. Our hypotesis is that spruce and beech forest vegetation are able to modify the chemical characteristics of organic horizon, hence the content of Al species.

Profile distribution and temporal changes of sulphate and nitrate contents and related soil properties under beech and spruce forests.

The behaviour of principal inorganic anions in forest soils, originating mainly from acid deposition, strongly influences the forest ecosystem response on acidification. The aim of this study was to describe seasonal and temporal changes of sulphate and nitrate contents and related soil properties under beech and spruce forests in a region heavily impacted by acidification. The Jizera Mountains area (Czech Republic) was chosen as such a representative mountainous soil ecosystem.

Comparison of water-soluble and exchangeable forms of Al in acid forest soils.

Soil acidification promotes Al release from minerals and parent bedrocks; it also affects Al mobilization and speciation. Speciation of KCl extractable and water-extractable Al in forest soils was done by means of HPLC/IC method. Species Al3+ were the most abundant Al forms in the KCl extracts (around 93%).

Health care reform in six Central European countries. A focus on health economic requirements in the drug pricing and reimbursement processes.

This study gives an overview of the health care reform in six Central European countries after the transition from a central planning system to a regulated market economy. We focused on cost containment policies for drugs, especially the requirements for submitting health economic data in the pricing and/or reimbursement processes. The literature review was supplemented with a survey with decision makers at national health authorities in each country.

Trends in consumption of calcium channel blockers in the Czech Republic during 1993-1999 and comparison with selected countries: drug utilization study.

Objective: To determine the patterns of consumption in calcium channel blockers (CCB) groups in the Czech Republic between 1992 and 1999 and make a comparison with selected countries.

Methods: This was part of a drug utilization study using WHO methodology [Anatomical Therapeutic Chemical classification/defined daily doses (ATC/DDD)]. The wholesale data collected by drug distributors were used.

Trace elements in end-stage renal disease. 2. Clinical implication of trace elements.

For human beings trace elements are essential nutrients with a gamut of functions. They are for instance indispensable components of many enzymes, so they have some regulatory functions and they may affect immune reactions and free radical generation. Abnormalities of trace elements are primarily the result of uremia, and they may be further modified and sometimes greatly exacerbated by the dialysis procedure.

Trace elements in end-stage renal disease. 1. Methodological aspects and the influence of water treatment and dialysis equipment.

For human beings trace elements are essential nutrients with a gamut of functions. They are for instance indispensable components of many enzymes, so they have some regulatory functions and they may affect immune reactions and free radical generation. Altered blood levels of different trace elements have been described in patients with advanced renal failure and especially in those treated by different kinds of renal replacement therapy.

Trace elements in hemodialysis and continuous ambulatory peritoneal dialysis patients.

Alterations in blood and tissue concentrations of trace elements in patients with chronic renal failure have been extensively investigated. Selenium, zinc and copper are elements which play an important role in biological systems as components of proteins, enzymes and antioxidants. The concentrations of selenium, zinc and copper were determined in the plasma, erythrocytes and whole blood of patients on regular hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) treatment using the method of inductively coupled plasma mass spectrometry (ICP-MS).

Chromium levels in patients with internal diseases.

Chromium (Cr), an essential element, mainly affects saccharide (potentiated insulin action via interaction with insulin receptor on the cell surface) and lipid metabolism (inhibition of hydroxymethylglutaryl-CoA reductase with a hypolipidemic effect). The aim of the study was to describe Cr serum levels in different diseases (malignant, metabolic, renal) using an advanced analytical technique with correlation to other biochemical parameters. The concentration was measured using atomic absorption spectrometry with electrothermal atomization.

ICRF-187 (dexrazoxan) protects from adriamycin-induced nephrotic syndrome in rats.

Background: Reactive oxygen species produced during metabolism of adriamycin are purported to play an important role in the pathogenesis of experimental adriamycin nephropathy in rats. ICRF-187 (dexrazoxan, Cardioxan), an iron chelator, has been shown to inhibit adriamycin-induced formation of hydroxyl radical and to decrease adriamycin cardiotoxicity in oncological patients. The aim of our study was to assess the putative protective role of ICRF-187 in adriamycin nephropathy by evaluating the possible participation of free radicals in its pathogenesis.

Retinol and alpha-tocopherol in hemodialysis patients.

The biological effects of reactive oxygen species and other radicals controlled by antioxidant mechanisms are modified by various enzymes and other substrates. Antioxidant substrates are divided into those with lipophilic and hydrophilic groups. Retinol and tocopherol are the main representations of lipophilic antioxidants.

[Dialysis therapy in the Czech Republic in 1995].

1. The number of haemodialyzation centres has more than doubled in the course of five years which increased the dialyzation capacity and at present no patient in the Czech Republic should be denied dialyzation treatment on technical or financial grounds. 2.

[Use of multivariate analysis in medical chemistry].

Alternations in trace elements concentrations are intensively studied because of their possible role in pathogenesis and progress of diseases. Three groups of patients were investigated: haemodialysis patients (HD) (n = 17), continual ambulatory peritoneal dialysis patients (CAPD) (n = 11), and control group of blood donors (n = 12). They were analyzed for Se, Zn and Cu concentration in plasma and erythrocytes by inductively--coupled plasma mass spectroscopy.

The influence of cyclosporin on lipid peroxidation and superoxide dismutase in adriamycin nephropathy in rats.

Cyclosporin A (CsA) was shown to reduce proteinuria in nephrotic syndrome, but its potential to increase lipid peroxidation may play a role in cyclosporin nephrotoxicity. The influence of cyclosporin treatment on the lipid peroxidation (assessed as malondialdehyde (MDA) in plasma and kidney homogenates using HPLC and reaction with thiobarbituric acid) and the activity of superoxide dismutase (SOD) in erythrocytes was studied in rats with nephrotic syndrome induced by single intravenous injection of adriamycin. Rats with nephrotic syndrome treated from the beginning with cyclosporin had lower proteinuria than untreated nephrotic rats.

The influence of pefloxacine on experimental adriamycin-induced nephrotic syndrome in rats.

Initial reports on antiproteinuric effect of pefloxacine in small groups of patients with minimal-change nephropathy (MCN) and focal and segmental glomerulosclerosis (FSGS) have not been confirmed in other papers. To assess its antiproteinuric effect in experimental animals we administered pefloxacine to rats with adriamycin nephropathy showing morphological changes resembling human minimal-change disease or focal segmental glomerulosclerosis, and clinically with full-blown nephrotic syndrome. Pefloxacine treatment was at least partially effective in preventing further increase of proteinuria in rats with adriamycin nephropathy.

[Lipid peroxidation and activity of antioxidative enzymes in patients with multiple myeloma].

Backgrounds: Reactive oxygen species and other free radicals are known to be the mediators of phenotypic and genotypic changes that lead from mutation to neoplasia. The imbalance in tumor cell antioxidant defense mechanism can influence also the sensitivity to cytoreductive therapy. In erythrocytes it can results to hemolysis which is one of pathogenetic mechanisms of anemia in cancer patients.

Lipid peroxidation and antioxidant enzymes in CAPD patients.

The mechanisms of free-radical injury include reactions with proteins, nucleic acids, and polysaccharides; and covalent binding to membrane components and initiation of lipid peroxidation. Cells have developed antioxidant defense to prevent free-radical injury including superoxide dismutase (SOD) and glutathione peroxidase (GPx). Significantly higher concentrations of total malondialdehyde (MDA) in plasma (1.