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Um SCAP – short chained alkylphenols – als kontaminationsspezifischen Fingerabdruck sowie als Transport- und Prozessindikatoren im Grundwasser nutzen zu konnen, mussen die einzelnen Verbindungen entsprechende Unterschiede in ihren chemisch-physikalischen Eigenschaften aufweisen. Die fur Phenol noch sehr guten Wasserloslichkeiten sinken mit weiterer Alkylierung. Wahrend das Phenol sehr kleine Verteilungsgleichgewichtskoeffizienten logKOW und logKOC hat, steigen diese mit zunehmendem Alkylierungsgrad innerhalb der Gruppe der SCAP an. Hieraus resultiert deren Fraktionierungspotenzial beim Transport, welches anhand eines Feldbeispiels veranschaulicht wird. Bewertungen der Toxizitat und des Abbauverhaltens zeigen Diskrepanzen uber den Kenntnisstand der SCAP auf, deuten die Machbarkeit von Natural Attenuation aber prinzipiell an. Die aufgezeigten umweltrelevanten Eigenschaften belegen das auserst dynamische Transportverhalten kurzkettiger Alkylphenole und eroffnen somit neue Anwendungspotenziale wie deren Nutzung als Transport- und Prozessindikatoren.

Objective and methods Acute modification of plasma lipidomic profile was assessed by top-down shotgun profiling on a LTQ Orbitrap hybrid mass spectrometer in 14 patients treated with two different apheresis techniques: plasma lipidfiltration (LF) and whole blood dextran sulfate adsorption (DSA). Results Patients treated with DSA revealed a significantly more pronounced reduction of LDL-cholesterol (LDL-C), a diminished decrease of HDL-cholesterol (HDL-C) and triglycerides (TG), and a similar reduction in lipoprotein (a) (Lp(a)) level. Against the overall tendency of reduction of lipid metabolites of all lipid classes in post-apheresis plasma, independent of apheresis technology applied, a highly significant increase of phosphatidylethanolamines (PE) in response to DSA was observed. Conclusion These data indicate that DSA technology may be associated with an activation or damage of blood cells at contact surface which subsequently leads to a massive liberation of cellular and membrane PE's. Pathophysiological consequences, especially with respect to coagulation system and oxidative stress, have to be further elucidated.

Aus der Literaturrecherche und eigenen Untersuchungen geht hervor, dass kurzkettige Alkylphenole (SCAP) während der Verarbeitungs- bzw. Veredelungsprozesse fester fossiler Brennstoffe ebenso in die Umwelt freigesetzt werden können, wie basierend auf Prozessen verschiedenster Industrien. Die große Bandbreite an Verwendungs- und Anwendungsmöglichkeiten von SCAP bringt viele Eintragsmöglichkeiten in die Umweltmedien mit sich. Prägnant sind die prozessbedingten SCAP-Muster (vorkommende Einzelsubstanzen) der verschiedenen Industrien und Produkte, wodurch Eintragsquellen und Fließpfade genauer quantifiziert werden können. Natürliche Eintragsquellen von SCAP mit Konzentrationen bis zu mehreren Tausend ppm sind ausschließlich Erdöle bzw. erdölführende Gesteine. Dieser Sachverhalt in Verbindung mit ihren chemisch-physikalischen Eigenschaften begründet die Verwendung der SCAP als Fluss- und Prozessindikatoren in der Erdöl-Reservoir-Erkundung und -Förderung. Anlehnend daran ist der oft noch fehlende Kenntnisstand der Umweltrelevanz und -akzeptanz von SCAP in Grundwasser-Schadensfällen in Deutschland nicht nachzuvollziehen. Es wird verdeutlicht, dass SCAP neben Erdölreservoiren auch für den Wasserkreislauf als Fluss- und Prozessindikatoren prädestiniert sind. peerReviewed

River monitoring with focus on the correlation of 41 micro-contaminants with K + and its temporal and spatial variation was carried out in the Leine River (Germany). A positive correlation of concentrations of wastewater-related micro-contaminants and K + is to be expected in receiving waters of wastewater treatment plant (WWTP) effluent since urine is a significant source of K + in WWTP effluent. This correlation was found for compounds, which meet the following criteria: (1) WWTP effluent is the dominating source of the compound, (2) variability of its mass flux in the WWTP is negligible, and (3) the compound is persistent in WWTPs and in the environment. The excellent positive correlation of carbamazepine with K + resulted in the fitting of a universal linear equation to the summer and winter data. For almost all other correlating compounds (1H-benzotriazole, citalopram, diclofenac, metoprolol, sotalol, sulfamethoxazole and tolyltriazole), slopes of the line fittings were steeper in winter ( x -axis: K + , y -axis: respective micro-contaminant). This has been attributed to a presumed lower degree of degradation and attenuation within WWTPs and in the environment due to low temperatures as well as an increase in consumption of these compounds in the winter months. As part of this research, a sampling event along the entire flow path of the Leine River (∼280 km) was conducted to identify compounds demonstrating stable ratios of various respective micro-contaminants with K + . Among other compounds, carbamazepine, sulfamethoxazole, and tolyltriazole demonstrated the best correlations with R 2 > 0.89. Potassium-equivalents of the individual micro-contaminants depended on land use and population structure of the investigated river section.

RNA interference (RNAi) is a widely used method for analysis of gene function in tissue culture cells. However, to date there has been no reliable method for testing the specificity of any particular RNAi experiment. The ideal experiment is to rescue the phenotype by expression of the target gene in a form refractory to RNAi. The transgene should be expressed at physiological levels and with its different splice variants. Here, we demonstrate that expression of murine bacterial artificial chromosomes in human cells provides a reliable method to create RNAi-resistant transgenes. This strategy should be applicable to all eukaryotes and should therefore be a standard technology for confirming the specificity of RNAi. We show that this technique can be extended to allow the creation of tagged transgenes, expressed at physiological levels, for the further study of gene function.

RNA interference (RNAi) is an evolutionarily conserved defence mechanism whereby genes are specifically silenced through degradation of messenger RNAs; this process is mediated by homologous double-stranded (ds)RNA molecules. In invertebrates, long dsRNAs have been used for genome-wide screens and have provided insights into gene functions. Because long dsRNA triggers a nonspecific interferon response in many vertebrates, short interfering (si)RNA or short hairpin (sh)RNAs must be used for these organisms to ensure specific gene silencing. Here we report the generation of a genome-scale library of endoribonuclease-prepared short interfering (esi)RNAs from a sequence-verified complementary DNA collection representing 15,497 human genes. We used 5,305 esiRNAs from this library to screen for genes required for cell division in HeLa cells. Using a primary high-throughput cell viability screen followed by a secondary high content videomicroscopy assay, we identified 37 genes required for cell division. These include several splicing factors for which knockdown generates mitotic spindle defects. In addition, a putative nuclear-export terminator was found to speed up cell proliferation and mitotic progression after knockdown. Thus, our study uncovers new aspects of cell division and establishes esiRNA as a versatile approach for genomic RNAi screens in mammalian cells.