Survey of <Emphasis Type="Italic">Alternaria</Emphasis> toxin contamination in food from the German market,using a rapid HPLC-MS/MS approach

A HPLC-MS/MS-based method for the quantification of nine mycotoxins produced by fungi of the genus Alternaria in various food matrices was developed. The method relies on a single-step extraction, followed by dilution of the raw extract and direct analysis. In combination with an analysis time per sample of 12 min, the sample preparation is cost-effective and easy to handle. The method covers alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), altenuene (ALT), iso-altenuene (isoALT), tentoxin (TEN), altertoxin-I (ATX-I), and the AAL toxins TA₁ and TA₂. Some Alternaria toxins which are either not commercially available or very expensive, namely AOH, AME, ALT, isoALT, and ATX-I, were isolated as reference compounds from fungal cultures. The method was extensively validated for tomato products, bakery products, sunflower seeds, fruit juices, and vegetable oils. AOH, AME, TeA, and TEN were found in quantifiable amounts and 92.1 % of all analyzed samples (n?=?96) showed low level contamination with one or more Alternaria toxins. Based on the obtained results, the average daily exposure to Alternaria toxins in Germany was calculated.     

Phylogenetic conservation of freshwater lake habitat preference varies between abundant bacterioplankton phyla

Despite their homogeneous appearance, aquatic systems harbour heterogeneous habitats resulting from nutrient gradients, suspended particulate matter and stratification. Recent reports suggest phylogenetically conserved habitat preferences among bacterioplankton, particularly for particle‐associated (PA) and free‐living (FL) habitats. Here, we show that independent of lake nutrient level and layer, PA and FL abundance‐weighted bacterial community composition (BCC) differed and that inter‐lake BCC varied more for PA than for FL fractions. In low‐nutrient lakes, BCC differences between PA and FL fractions were larger than those between lake layers. The reverse was true for high‐nutrient lakes. Nutrient level affected BCC more in hypolimnia than in epilimnia, likely due to hypolimnetic hypoxia in high‐nutrient lakes. In line with previous reports, we observed within‐phylum operational taxonomic unit (OTU) habitat preference conservation, although not for all phyla, including the phylum with the highest average relative abundance across all habitats (Bacteroidetes). Consistent phylum‐level habitat preferences may indicate that the functional traits that underpin ecological adaptation of freshwater bacteria to lake habitats can be phylogenetically conserved, although the levels of conservation are phylum dependent. Resolving taxa preferences for freshwater habitats sets the stage for identification of traits that underpin habitat specialization and associated functional traits that influence differences in biogeochemical cycling across freshwater lake habitats.     

Dysfunctional mitochondrial fission impairs cell reprogramming

We have recently shown that mitochondrial fission is induced early in reprogramming in a Drp1-dependent manner; however, the identity of the factors controlling Drp1 recruitment to mitochondria was unexplored. To investigate this, we used a panel of RNAi targeting factors involved in the regulation of mitochondrial dynamics and we observed that MiD51, Gdap1 and, to a lesser extent, Mff were found to play key roles in this process. Cells derived from Gdap1-null mice were used to further explore the role of this factor in cell reprogramming. Microarray data revealed a prominent down-regulation of cell cycle pathways in Gdap1-null cells early in reprogramming and cell cycle profiling uncovered a G2/M growth arrest in Gdap1-null cells undergoing reprogramming. High-Content analysis showed that this growth arrest was DNA damage-independent. We propose that lack of efficient mitochondrial fission impairs cell reprogramming by interfering with cell cycle progression in a DNA damage-independent manner.     

Wireless ECG measurement system with capacitive coupling]

This paper describes a measurement system that captures an electrocardiogram (ECG) using capacitively coupled electrodes. The measurement system was integrated into an off-the-shelf office chair (so-called "Aachen SmartChair"). Whereas for classical ECG measurement adhesive is used to attach conductively coupled electrodes to bare skin, the system presented allows ECG measurement through clothing without direct skin contact. Furthermore, a ZigBee communication module was integrated to allow wireless transmission of ECG data to a PC or an ICU patient monitor. For system validation, classical ECG using conductive electrodes was obtained simultaneously. First measurement results, including variations of cloth thickness and material, are presented and some of the system-specific problems of this approach are discussed.