Daniela Bartsch

Ras is a universal eukaryotic intracellular protein integrating extracellular signals from multiple receptor types. To investigate its role in the adult central nervous system, constitutively activated V12-Ha-Ras was expressed selectively in neurons of transgenic mice via a synapsin promoter. Ras-transgene protein expression increased postnatally, reaching a four- to fivefold elevation at day 40 and persisting at this level, thereafter. Neuronal Ras was constitutively active and a corresponding activating phosphorylation of mitogen-activated kinase was observed, but there were no changes in the activity of phosphoinositide 3-kinase, the phosphorylation of its target kinase Akt/PKB, or expression of the anti-apoptotic proteins Bcl-2 or Bcl-X(L). Neuronal Ras activation did not alter the total number of neurons, but induced cell soma hypertrophy, which resulted in a 14.5% increase of total brain volume. Choline acetyltransferase and tyrosine hydroxylase activities were increased, as well as neuropeptide Y expression. Degeneration of motorneurons was completely prevented after facial nerve lesion in Ras-transgenic mice. Furthermore, neurotoxin-induced degeneration of dopaminergic substantia nigra neurons and their striatal projections was greatly attenuated. Thus, the Ras signaling pathway mimics neurotrophic effects and triggers neuroprotective mechanisms in adult mice. Neuronal Ras activation might become a tool to stabilize donor neurons for neural transplantation and to protect neuronal populations in neurodegenerative diseases.

Abstract In this article, we present a multiplex real-time PCR method for a simultaneous, sensitive and specific detection and semi-quantitative estimation of the allergenic species peanut, hazelnut, walnut and cashew in food. Due to the use of multicopy target sequences, a very sensitive detection of the allergenic ingredients was possible. The method was validated in-house as well as by a collaborative trial with 12 laboratories. Within the ring trial, 0.64 mg/kg (i.e. approx. 0.1–0.2 mg of peanut and tree nut-derived protein/kg) could still be detected in a processed cookie matrix, confirmed by results of incurred, processed samples spiked at very low levels between 0.9 and 50 mg/kg of the corresponding allergenic ingredient (peanut, tree nut). In addition, the method revealed good precision data. With regard to quantitative analysis though, insufficient recovery data (bias) were determined in some cases, resulting in measurement uncertainties of more than 50%.

Abstract The international working group “Development of methods for identification of foodstuffs produced by means of genetic engineering techniques” was established pursuant to § 64 of the German Food and Feed Code (LFGB). It has developed a guideline for implementing and verifying digital PCR methods previously validated as real-time PCR techniques. While event-specific methods in testing of genetically modified organisms (GMO) have traditionally relied on real-time PCR, new digital PCR technologies offer significant advantages and therefore, leading to an increased use by control laboratories. This guideline provides practical recommendations for transferring the real-time PCR to digital PCR and for verifying the digital PCR method. The guideline is applicable to analysis of GMO in food, feed and seed and is freely available on the website of the Federal Office of Consumer Protection and Food Safety (BVL).

The quality of medical education is an ongoing challenge due to the continuing changes of the health-care politics and general social conditions. At many German university hospitals the dominating picture is overfilled courses, lack of hands-on practice, reduced patient contact and the dull provision of theoretical, abstract knowledge. The reformed surgical curriculum at the University of Marburg university hospital is used to demonstrate that, in spite of large student numbers, a practice-oriented, small-group training at a high didactic level is possible. The surgical training courses are organized in detail and coordinated. Course contents and structure are media available in print and online versions for both students and teachers and thus fulfill not only transparency needs but also contemporary requirements. The strategy of a practice- and patient-oriented, small-group training is followed strictly in the surgical curriculum. In addition, accompanying tutorial possibilities for individual study in an up-to-date learning center are offered. Here the students have the opportunity to intensify knowledge acquired in previous or future courses with numerous attractive education means. Continuous evaluation of the individual training courses at the end of each semester not only document motivation of the students but also serve to continuously improve the training concepts.

In the field of animal differentiation, work on standardizing methods has been intensified in Germany in recent years, not least due to the horsemeat scandal in 2013. Even though there are now hardly ever any positive findings anymore in examinations to detect horse adulterations in foods such as lasagne, animal differentiation altogether ranks high in detecting adulteration of foods. This article, therefore, summarises the current status of analytical techniques used in Germany with standardization at German level. It has been established by the working group Biochemical and Molecular Biological Analytics of the Lebensmittelchemische Gesellschaft (Food Chemistry Society within the German Chemical Society) with support of experts in the working group “Molecular techniques for differentiating plant and animal species (§64 of the German Food and Feed Code - LFGB) and the Immunology and molecular biology task force of the food hygiene and food of animal origin working group (ALTS), both from Germany.