The dioRAMA project: assessment of dioxin-like activity in sediments and fish (Rutilus rutilus) in support of the ecotoxicological characterization of sediments

Introduction

Given the complex interactions of re-suspension processes and bioavailability of sediment-bound pollutants such as dioxin-like chemicals, there is need for a better integrative understanding of the cause–effect relationship of these pollutants. Currently, the majority of studies investigating potential risks of these chemicals only focus on characterizing sediment extracts via in vitro bioassays, thereby disregarding bioavailability, uptake, metabolism, and elimination rates of these compounds in vivo. To determine to which extent mechanism-specific effects in vitro reflect possible adverse effects in vivo, the research project dioRAMA, involving partnership between the Institute for Environmental Research of RWTH Aachen University and the Department Biochemistry/Ecotoxicology of the German Federal Institute of Hydrology, was established.

Methods

Animals from an elevated trophic level—common roach (Rutilus rutilus)—will be exposed to sediments from two major German rivers. Exposure will be performed in a system that enables a concurrent monitoring of environmental parameters. In parallel, in vitro studies will be conducted to determine dioxin-like potentials of sediment and fish extracts from the in vivo exposure experiments using different cell lines with varying endpoints. Moreover, extract fractionation procedures, using the strategy of effect-directed analysis, will enable the detection of specific contaminant groups responsible for the biological activity observed.

Conclusion

A closer interconnection between applied ecotoxicological science and regulatory needs will facilitate the improved assessment of dioxin-like compounds in sediment and biota. Consequently, this will enable their application in sediment management programs, which is one of the main goals of the dioRAMA project.     

Untersuchungen zur CO2-Gas-Austauschrate bei transgenen Fructan bildenden Kartoffellinien ( Solanum tuberosum L.) unter Einsatz eines modularen Großküvettensystems: (Investigations to the CO2 gas exchange rate in transgenic fructans generating potato lines ( Solanum tuberosum L.) by implementation of a modular cuvette system)

Abstract

This survey was aimed at comparing the CO₂ gas exchange rate of transgenic potato lines and of the isogenic line Désirée in order to establish if genetic modification has resulted in ecologically relevant changes. In examining two transgenic potato lines and one isogenic line, a modular whole-plant cuvette system was implemented for the first time. Furthermore, suitability of such a cuvette system for comparative examination was to be tested in the survey at hand. The lowest CO₂ exchange rate was observed in the SST/FFT line. The SST line achieved the highest CO₂ exchange rate of all genotypes tested. Measurement of CO₂ exchange rate, and additionally collected data on morphologic and characteristics of yield physiology, resulted in distinctly correlating data. The phenotypical changes observed could be classified within the growth and yield profile specified by the German Federal Office of Plant Varieties (Bundessortenamt) for potato varieties permitted for cultivation in Germany. A changed growth rate of crop in the transgenic lines could not be established. A modular whole-plant cuvette system can be implemented in comparative gas exchange measurements in a partly air-conditioned cell.     

Equations for estimating the above-ground biomass of Larix sibirica in the forest-steppe of Mongolia

Biomass functions were established to estimate above-ground biomass of Siberian larch (Larix sibirica) in the Altai Mountains of Mongolia. The functions are based on biomass sampling of trees from 18 different sites, which represent the driest locations within the natural range of L. sibirica. The best performing regression model was found for the equations y = (D ² H)/(a+bD) for stem biomass, y = aD ^b for branch biomass, and y=aD ^b H ^c for needle biomass, where D is the stem diameter at breast height and H is the tree height. The robustness of the biomass functions is assessed by comparison with equations which had been previously published from a plantation in Iceland. There, y=aD ^b H ^c was found to be the most significant model for stem and total above-ground biomasses. Applying the equations from Iceland for estimating the above-ground biomass of trees from Mongolia resulted in the underestimation of the biomass in large-diameter trees and the overestimation of the biomass in thin trees. The underestimation of thick-stemmed trees is probably attributable to the higher wood density, which has to be expected under the ultracontinental climate of Mongolia compared to the euoceanic climate of Iceland. The overestimation of the biomass in trees with low stem diameter is probably due to the high density of young growth in the not systematically managed forests of the Mongolian Altai Mountains, which inhibits branching, whereas the plantations in Iceland are likely to have been planted in lower densities.     

Controlled vocabularies for plant anatomical parts optimized for use in data analysis tools and for cross-species studies

Background

It is generally accepted that controlled vocabularies are necessary to systematically integrate data from various sources. During the last decade, several plant ontologies have been developed, some of which are community specific or were developed for a particular purpose. In most cases, the practical application of these ontologies has been limited to systematically storing experimental data. Due to technical constraints, complex data structures and term redundancies, it has been difficult to apply them directly into analysis tools.

Results

Here, we describe a simplified and cross-species compatible set of controlled vocabularies for plant anatomy, focussing mainly on monocotypledonous and dicotyledonous crop and model plants. Their content was designed primarily for their direct use in graphical visualization tools. Specifically, we created annotation vocabularies that can be understood by non-specialists, are minimally redundant, simply structured, have low tree depth, and we tested them practically in the frame of Genevestigator.

Conclusions

The application of the proposed ontologies enabled the aggregation of data from hundreds of experiments to visualize gene expression across tissue types. It also facilitated the comparison of expression across species. The described controlled vocabularies are maintained by a dedicated curation team and are available upon request.

     

Tumor necrosis factor signaling requires iRhom2 to promote trafficking and activation of TACE

The cytokine tumor necrosis factor (TNF) is the primary trigger of inflammation. Like many extracellular signaling proteins, TNF is synthesized as a transmembrane protein; the active signal is its ectodomain, which is shed from cells after cleavage by an ADAM family metalloprotease, ADAM17 (TNFα-converting enzyme, TACE). We report that iRhom2 (RHBDF2), a proteolytically inactive member of the rhomboid family, is required for TNF release in mice. iRhom2 binds TACE and promotes its exit from the endoplasmic reticulum. The failure of TACE to exit the endoplasmic reticulum in the absence of iRhom2 prevents the furin-mediated maturation and trafficking of TACE to the cell surface, the site of TNF cleavage. Given the role of TNF in autoimmune and inflammatory diseases, iRhom2 may represent an attractive therapeutic target.     

The conflict over Veracel pulpwood plantations in Brazil — Application of Ethical Analysis

The large-scale pulp investment model, with its pressure on land, has created conflict and caused major disagreements and open hostility amongst the social movement and NGO networks, state actors, and the pulp and paper companies in Brazil. In this article, Ethical Analysis was applied in the assessment of the dynamics and possibilities of conflict resolution related to the expansion of pulpwood plantations in Brazil's Bahia State, particularly near Veracel Celulose. Ethical Analysis as a tool identifies the complex dynamics of contention through identifying bridges and rifts in the social, ecological and economic viewpoints of the main actors. The analysis was based on field research, interviews, and a review of existing literature. The results indicated that the conflict is marked by politics of power, and as long as this stage continues, the politics of cooperation and conflict resolution would be hard to achieve. The key actors have diverging interests, values and principles, and different ways of presenting their viewpoints. The current investment context is economically and institutionally peripheral and socially weak. Without a radical rethinking and emphasis on ethical and structural reworking of the investment model, the conflict will likely continue to deepen, aggravating investment risk for large-scale business and industrial forestry.     

Epizootic hemorrhagic disease virus infection of type I interferon receptor deficient mice

Type I interferon receptor deficient (IFNAR(-/-)) mice were infected with an Israeli isolate of serotype 7 of epizootic hemorrhagic disease virus (EHDV; Orbivirus, Reoviridae). Two out of two mice that received 5×10(5) 50% tissue culture infectious doses (TCID(50)) by intraperitoneal injection died or were euthanized in a moribund state on day 5 after infection. One mouse out of three that had been inoculated with 5×10(2) TCID(50) died on day 7 while the remaining mice did not show any clinical signs and survived until the end of the experiment. Spleens of all dead mice were highly positive in an EHDV real-time RT-PCR (quantification cycle values ≤15) and contained ≥10(5.8) TCID(50) of virus per ml of homogenate. The viral RNA content and virus titer in the spleens of the two surviving mice, on the other hand, were over 100-fold lower. Different from data reported for BTV, the outcome of EHDV infection of IFNAR(-/-) mice is dose-dependent and subclinical infections can occur.     

The possible enhancement of parvovirus vaccination on the mortality rate of diseased dogs

A survey was conducted by using questionnaires dealing with morbidity and mortality of young dogs. Seventy-one clinical evaluations of diseased dogs were included in this survey. The cases were divided into 3 groups according to their vaccination history: 1. dogs vaccinated with the parvovirus and distemper live modified vaccine; 2. dogs vaccinated with the killed parvovirus vaccine; 3. non-vaccinated dogs. Statistical analysis of the information obtained by analyzing the questionnaires gave the following results: The survival rate of the non-vaccinated and killed parvovirus vaccine-vaccinated dogs was significantly higher than that of the dogs which were vaccinated by the live modified vaccine. No such difference was encountered between groups 2 and 3. This finding, once more, supports the notion that the live modified parvovirus vaccine may have an immunosuppressive property.     

Production and predation rates in a cannibalistic Arctic char (Salvelinus alpinus L.) population

Abstract – Production of cannibalistic Arctic char ( Salvelinus alpinus (L.)) and their prey conspecifics were estimated in an allopatric population, situated in an alpine ultraoligotrophic lake in central Norway. Estimates of population abundance were obtained by mark recapture and successive removal experiments. Assuming stable age distribution, we estimated mean yearly biomass (±95% CL) of char in sampled size groups vulnerable to predation (60 to 150 mm) to 7.93 (5.11–14.30) kg · ha⁻¹. Similarly, mean yearly biomass (±95% CL) of cannibalistic char (> 250 mm) was estimated to 0.62 (0.50–1.06) kg · ha⁻¹. Annual production (±95% CL) of char in length groups 60 to 150 mm was estimated to be 4.31 (2.74–8.03) kg · ha⁻¹ · year⁻¹, and production (±95% CL) of cannibalistic char to 0.19 (0.15–0.33) kg · ha⁻¹ · year⁻¹. Depending on the food conversion factor (set to vary from 0.1 to 0.4), the cannibalistic char removed from 10% to 40% of the production of char in sampled size-classes vulnerable to predation yearly. The overall ecological efficiency in energy transfer between the prey and predator population was 4.4%.     

Assessing parent material uniformity of a red and black soil complex in the landscapes

The distribution of red and black soil (Xeralfs–Xerolls) associations in the Monarto area (South Australia) is complex and their genesis either being derived from a uniform parent material or a lithologic discontinuity is not known. The objectives of this study were (i) to assess Zr- and Ti-bearing grains as minerals resistant to chemical weathering prior to employing Zr and Ti in determining parent material uniformity, and (ii) to confirm whether pedological processes or a lithologic discontinuity may be responsible for the textural contrast within the red and black soil profiles. Scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX) were used to study chemical weathering and elemental composition of surfaces of Zr- and Ti-bearing grains. X-ray fluorescence (XRF) analysis was used to determine elemental concentrations in various soil fractions. Results showed that Zr-bearing grains consisted of only zircon having smooth clean surfaces, which are characteristic of a mineral resistant to chemical weathering. EDAX spectra confirmed that Zr was a specific element to represent zircon, suggesting its reliability to be used in assessing parent material uniformity. On the other hand, Ti derived not only from minerals (rutile/anatase) resistant but also from minerals (ilmenite/pseudorutile, biotite) susceptible to chemical weathering. This limited the usefulness of Ti as an index mineral for soil development studies. Except for Zr:Ti ratio, all other indicators of parent material uniformity, i.e., depth distribution curves of Zr and Y in various fractions and Y:Zr ratio showed no considerable inflection and variation with depth in a Xeralf (red soil). This indicated the Xeralf derived from a uniform parent material (mica schists), thereby texture contrast within a profile is due to pedological processes. On the other hand, depth distribution curves showed clear inflection and variation in Xerolls (black soils), indicating soils developed from lithologic discontinuities, so different trends in particle size fractions between 0–48 cm for MA5 and 0–59 cm for MA3 profiles compared to the underlying layers are due to parent material differences and not pedogenesis. The presence of complex red and black soil association in the landscape is attributed to the difference in parent materials, where the red soil developed from mica schist and the black soils from calcareous deposits.