Persistent mercury hot spot in Central Europe and Skalka Dam reservoir as a long-term mercury trap.

This study aimed to evaluate the relevance of the floodplain pollution sinks of the legacy mercury (Hg) hot spot in Kössein-Röslau river system (east Bavaria, Germany) for further mobilisation and fluvial transport of mercury in suspended particulate matter (SPM), as an important transport medium of Hg in aquatic systems. The channel belt fluvial erosion as the secondary pollution pathway was also considered. The hot spot has originated from the production of Hg compounds such as C2H5HgCN and C6H5HgCl in Chemical Factory Marktredwitz, and even more than 30 years after the factory abandonment, the Kössein and the Röslau rivers still export polluted fine grained SPM (median 25-35 µm) with mean annual concentrations of 17.4 mg/kg. SPM sampling was performed by floating samplers, supported by floodplain drill cores and by recent channel sediments manually collected along the polluted rivers further. Based on long-term monitoring data set from state enterprise Povodí Ohre, fish in the Skalka Reservoir have had Hg concentrations in their muscles up to 6 mg/kg for at least the last 14 years, exceeding the European maximal limit of 0.5 mg/Hg/kg. In addition, the Hg inventory in the Kössein-Röslau river stretches was therefore calculated; it produced an estimate of ca. 21 t Hg in a 22-km-long channel belt, prone to fluvial remobilisation during floods. Although a major portion of the fluvially transported Hg has yet been trapped by the Skalka Reservoir, the Hg content in the SPM exported farther downstream still varies between 2 and 10 mg/kg Hg. Due to the considerable Hg inventory in the Kössein-Röslau rivers, an improvement will not occur downstream unless specific measures target the secondary pollution mechanism(s).

Adeno-associated viral serotypes differentially transduce inhibitory neurons within the rat amygdala.

Recombinant adeno-associated viruses (AAV) are frequently used to make localized genetic manipulations within the rodent brain. It is accepted that the different viral serotypes possess differing affinities for particular cell types, but it is not clear how these properties affect their ability to transduce specific neuronal cell sub-types. Here, we examined ten AAV serotypes for their ability to transduce neurons within the rat basal and lateral nuclei of the amygdala (BLA) and the central nucleus of the amygdala (CeA). AAV2 based viral genomes designed to express either green fluorescent protein (GFP) from a glutamate decarboxylase (GAD65) promoter or the far-red fluorescent protein (E2-Crimson) from a phosphate-activated glutaminase (PAG) promoter were created and pseudotyped as AAV2/1, AAV2/4, AAV2/5, AAV2/6, AAV2/7, AAV 2/8, AAV2/9, AAV2/rh10, AAV2/DJ and AAV2/DJ8. These viruses were infused into the BLA and CeA at equal titers and twenty-one days later tissue within the amygdala was examined for viral transduction efficiency. These serotypes transduced neurons with similar efficiency, except for AAV4 and AAV5, which exhibited significantly less efficient neuronal transduction. Notably, AAV4 and AAV5 possess the most divergent capsid protein sequences compared to the other commonly available serotypes. We found that the Gad65-GFP virus did not exclusively express GFP within inhibitory neurons, as assessed by fluorescent in situ hybridization (FISH), but when this virus was used to transduce CeA neurons, the majority of the neurons that expressed GFP were in fact inhibitory neurons and this was likely due to the fact that this nucleus contains a very high percentage of inhibitory neurons.

Polymer-induced bundling of F actin and the depletion force.

The inert polymer polyethylene glycol (PEG) induces a "bundling" phenomenon in F actin solutions when its concentration exceeds a critical onset value C(o). Over a limited range of PEG molecular weight and ionic strength, C(o) can be expressed as a function of these two variables. The process is reversible, but hysteresis is also observed in the dissolution of the bundles, with ionic strength having a large influence. Additional actin filaments are able to join the previously formed bundles. PEG polymers are not incorporated into the actin bundles. Estimates of the Asakura-Oosawa depletion force, Coulomb repulsion, and van der Waals potential are combined in order to explain the bundling effect and hysteresis. Conjectures are presented concerning the apparent limit in bundle size.

[8 years experience with heroin-assited treatment in Switzerland--current results and future improvements]. / Acht Jahre Erfahrung mit der heroingestützten Behandlung in der Schweiz--aktuelle Ergebnisse und künftige Weiterentwicklung.

In 1994, Switzerland introduced experimental heroin assisted treatment for refractory opioid addicts as last line of treatment. An evaluation research was established examining effectiveness and cost-benefit of heroin-assisted treatment for the first project phase between 1994 and 1996. The present publication intends to provide an overview for the newer results of the evaluation. In summary, the positive outcomes found at first follow-ups continued to persist regarding somatic and mental improvements, social integration including reduction of criminal behaviour, and reduction of use of illicit drugs. In future, treatment of co-morbid mental disorders, integration into the labour market and persistent consumption of cocaine in some patients still need focussed attention. Different efforts to assure quality control and development hopefully will serve towards further optimisation of heroin-assisted treatment.