Usefulness of automated chromatography for rapid fetal blood analysis for second trimester prenatal diagnosis of β-thalassemia

Prenatal diagnosis of β-thalassemia is now ideally done in the first trimester of pregnancy by chorionic villus tissue DNA analysis. Nevertheless, fetal blood analysis in the second trimester is required either when the mutation in both parents cannot be characterised or when the couple comes late for investigations. We evaluated the usefulness of analysis of fetal blood on the Biorad Variant Hemoglobin Testing System using the β-thalassemia short programme in comparison with the conventional globin biosynthesis in 58 pregnancies. The β/α biosynthesis ratios in 13 homozygous fetuses ranged from 0 to 0.03 and the adult hemoglobin (HbA) levels by automated chromatography varied from 0% to 0.4%. The normal or heterozygous fetuses had β/α ratios of >0.04 and HbA levels ranging from 2.1% to 10.6%. In 17 fetuses we also correlated the β gene mutations with the predicted genotypes using automated high-performance liquid chromatography (HPLC). Follow-up of 18 unaffected fetuses using the Variant System at birth showed a significant increase in HbA levels. Copyright © 2002 John Wiley & Sons, Ltd.     

The changing character of household waste in the Czech Republic between 1999 and 2009 as a function of home heating methods

The authors of this paper report on the changing character of household waste, in the Czech Republic between 1999 and 2009 in households differentiated by their heating methods. The data presented are the result of two projects, financed by the Czech Ministry of Environment, which were undertaken during this time period with the aim of focusing on the waste characterisation and complete analysis of the physicochemical properties of the household waste. In the Czech Republic, the composition of household waste varies significantly between different types of households based on the methods of home heating employed. For the purposes of these studies, the types of homes were divided into three categories – urban, mixed and rural. Some of the biggest differences were found in the quantities of certain subsample categories, especially fine residue (matter smaller than 20 mm), between urban households with central heating and rural households that primarily employ solid fuel such coal or wood. The use of these solid fuels increases the fraction of the finer categories because of the higher presence of ash. Heating values of the residual household waste from the three categories varied very significantly, ranging from 6.8 MJ/kg to 14.2 MJ/kg in 1999 and from 6.8 MJ/kg to 10.5 MJ/kg in 2009 depending on the type of household and season. The same factors affect moisture of residual household waste which varied from 23.2% to 33.3%. The chemical parameters also varied significantly, especially in the quantities of Tl, As, Cr, Zn, Fe and Mn, which were higher in rural households. Because knowledge about the properties of household waste, as well as its physicochemical characteristics, is very important not only for future waste management, but also for the prediction of the behaviour and influence of the waste on the environment as the country continues to streamline its legislation to the European Union’s solid waste mandates, the results of these studies were employed by the Czech Ministry of Environment to optimise the national waste management strategy.     

IMPROVED ENERGY AND MATERIAL EFFICIENCY USING NEW TOOLS FOR GLOBAL OPTIMISATION OF RESIDUE MATERIAL FLOWS

Residue materials generated in the metallurgical industry have gained an increasing importance, both from the points of view of energy and material supply. A joint process integration model for the integrated steel plant system is developed and used in this paper. It takes into account both residue materials and energy recirculation for the system. The potential for increased recirculation and the effect on the system from an environmental point of view is presented, and implementations and practical experiences are discussed. The model developed can serve as a benchmark for different steelmaking operations and constitute a basis for the continuous work involved in material, energy, environment or economic analyses for the steel production system.     

Enzyme-linked immunosorbent assay for ultratrace determination of antibiotics in aqueous samples

Two commercially available enzyme-linked immunosorbent assay (ELISA) kits that are commonly used for tylosin or tetracycline residues in meat and milk were adapted for ultratrace analysis of these antibiotics in surface and ground waters. These two antibiotics are commonly fed to swine, turkeys, and cattle at subtherapeutic doses for growth promotion purposes. Both ELISA techniques were found to be highly sensitive and selective for the respective antibiotics with detection limits of 0.10 and 0.05 microg L(-1) for tylosin and tetracycline, respectively. The recovery of both tylosin and tetracycline from spiked samples of lake waters, runoff samples, soil saturation extracts, and nanopure water was close to 100%. Tetracycline ELISA was highly specific for tetracycline and chlortetracycline but not for other forms of tetracycline (oxytetracycline, demeclocycline, and doxycycline). Analysis of a few liquid swine manure samples by liquid chromatography-mass spectrometry (LC-MS) showed lower concentrations for chlortetracycline as compared with concentrations obtained using ELISA. However, the concentrations of tylosin from ELISA were comparable with that of LC-MS. The lower concentrations of chlortetracycline obtained by LC-MS in manure samples indicate the presence of other similar or transformed compounds that were detected by ELISA but not determined by LC-MS. These results indicate that both ELISA kits can be useful tools for low-cost screening of tylosin, tetracycline, and chlortetracycline in environmental waters. Furthermore, both ELISA procedures are rapid, portable, and easily adaptable for testing of multiple samples simultaneously.     

Potential Remobilization of Toxic Anions during Reduction of Arsenated and Chromated Schwertmannite by the Dissimilatory Fe(III)-Reducing Bacterium Acidiphilium cryptum JF-5

Schwertmannite, an iron(III)-oxyhydroxysulfate formed in acidic mining-impacted stream or lake waters often contaminated with toxic elements like arsenate or chromate, is able to incorporate high amounts of these oxyanions. Detoxification of the water might be achieved if precipitated arsenated or chromated schwertmannite is fixed in the sediment. However, under reduced conditions, reductive dissolution of iron oxides mediated by the activity of Fe(III)-reducing bacteria might mobilize arsenate and chromate again. In this study, the reduction of synthesized arsenated or chromated schwertmannite by the acidophilic Fe(III)-reducer Acidiphilium cryptum JF-5, isolated from an acidic mining-impacted sediment, was investigated. In TSB medium at pH 2.7 with glucose as electron donor, A. cryptum JF-5 reduced about 10% of the total Fe(III) present in pure synthetic schwertmannite but only 5% of Fe(III) present in arsenated schwertmannite. In contrast to sulfate that was released during the reductive dissolution of pure schwertmannite, arsenate was not released during the reduction of arsenated schwertmannite probably due to the high surface complexation constant of arsenate and Fe(III). In medium containing chromated schwertmannite, no Fe(II) was formed, and no glucose was consumed indicating that chromate might have been toxic to cells of A. cryptum JF-5. Both As(V) or Cr(VI) could not be utilized as electron acceptor by A. cryptum JF-5. A comparison between autoclaved (121 °C for 20 min) and non-autoclaved schwertmannite samples demonstrated that nearly 100%of the bound sulfate was released during heating, and FTIR spectra indicated a transformation of schwertmannite to goethite. This structural change was not observed with autoclaved arsenated or chromated schwertmannite. These results suggest that the mobility of arsenate and chromate is not enhanced by the activity of acidophilic Fe(III)-reducing bacteria in mining-impacted sediments. In contrast, the presence of bound arsenate and chromate seemed to stabilize schwertmannite against reductive dissolution and its further transformation to goethite that is an ongoing process in those sediments.