Microplastic loads in Eurasian otter (Lutra lutra) feces-targeting a standardized protocol and first results from an alpine stream, the River Inn.

Microplastics (MP) are omnipresent in a wide range of environments, constituting a potential threat for aquatic and terrestrial wildlife. Effects in consumers range from physical injuries to pathological reactions. Due to potential bioaccumulation of MP, predators are of particular concern for MP induced health effects. The Eurasian otter is an apex predator in (semi-)aquatic habitats feeding primarily on fish. Furthermore, the species is classified as "near threatened" on the IUCN Red List. Thus, the Eurasian otter is of conservation concern and may serve as a bioindicator for MP pollution. Feces can be used to detect pollutants, including MP. Initial studies confirmed the presence of MP in otter feces (= spraints). However, as specific, validated protocols targeting at an efficient and standardized extraction of MP from otter spraints are missing, experimental results reported from different groups are challenging to compare. Therefore, we (i) present steps towards a standardized protocol for the extraction of MP from otter feces, (ii) give recommendations for field sample collection of otter spraints, and (iii) provide a user-friendly step-by-step workflow for MP extraction and analysis. Applying this framework to field samples from five study sites along the River Inn (n = 50), we detected MP of different sizes and shapes (ranging from microfibers to road abrasion and tire wear) in all otter spraint samples.

The use of surrogate standards as a QA/QC tool for routine analysis of microplastics in sewage sludge.

The efficient retention of microplastic particles (MP) during wastewater treatment results in their accumulation in the sewage sludge. Thus, sewage sludge represents a key matrix for understanding MP flows between engineered and natural systems. Building on previous reports, we present a sample preparation protocol optimized for digested sewage sludge. The key steps include acid digestion supported by Fenton reagents, enzymatic digestion, and density separation using sodium polytungstate (density of 1.9 gcm-3). We use colored polyethylene (PE) spheres as surrogate standards to assess sample specific recoveries in terms of number and size, based on visible light (vis) microscopy and focal plane array - micro-Fourier transform - infrared (FPA-µ-FT-IR) imaging. The FT-IR spectra of common MP were identical before and after the digestion procedures and morphological changes were observed for polylactide fibers only. Average recovery rates for PE spheres, polypropylene fibers and polyethylene terephthalate fragments extracted from spiked digested sewage sludge and determined using (automated) vis microscopy ranged from 80% to 100%. Similar recovery rates of around 80% were also obtained for PE spheres based on FPA-µ-FT-IR measurements. The median diameters of red and blue PE spheres in dry state and recovered from spiked deionized water and from extracts of spiked digested sewage sludge determined using vis microscopy ranged between 46 µm and 67 µm. These diameters were similar to 54 µm and 61 µm obtained from the FPA-µ-FT-IR measurements of the corresponding deionized water samples and digested sludge extracts and in line with data from the producer (53 µm-63 µm). Using our digestion protocol in combination with surrogate standards, we measured MP number concentrations of around 10,000 #/g in dried, digested sewage sludge, in agreement with recent results from other studies.

[Effort-Reward Imbalance in the Emergency Rescue Service - A Cross-Sectional Study on Prevalence and Influencing Factors among Full-Time Emergency Service Employees]. / Berufliche Gratifikationskrisen im Rettungsdienst ­ Eine Querschnittstudie zu Häufigkeit und Einflussfaktoren bei hauptamtlich tätigem Rettungsdienstpersonal.

INTRODUCTION: The emergency service is a challenging field of activity. The Effort-Reward Imbalance model explains on the basis of the ratio between reward/effort the appearance of occupational stress. For the first time, this study examines the extent of Effort-Reward Imbalance in rescue services in Germany. METHODS: Full-time emergency service employees of a German Red Cross District Association were consulted. N=82 employees (78.8%) participated (M age=37.78 years, 73.2% male). In addition to the Effort-Reward-Imbalance-Questionnaire, the study included other tools to measure anxiety, depression, health, social support, bullying and optimism of the employees. RESULTS: N=58 persons (70.7%) reported an effort-reward imbalance. The existence of an Effort-Reward Imbalance was related to older age, lower education, higher professional qualification (working as a paramedic) and existing partnership. Persons with an effort-reward imbalance reported poorer health and lower social support. DISCUSSION: The high number of persons with Effort-Reward Imbalance in emergency services in Germany coincides with international studies. CONCLUSION: The results demonstrates the need for preventive support and further research.

Mapping of common bunt resistance gene Bt9 in wheat.

KEY MESSAGE: The Bt9 resistance locus was mapped and shown to be distinct from the Bt10 locus. New markers linked to Bt9 have been identified and may be used to breed for resistance towards the seed-borne disease. Increasing organic wheat production in Denmark, and in other wheat-producing areas, in conjunction with legal requirements for organic seed production, may potentially lead to a rise in common bunt occurrence. As systemic pesticides are not used in organic farming, organic wheat production systems may benefit from genetic resistances. However, little is known about the underlying genetic mechanisms and locations of the resistance factors for common bunt resistance in wheat. A double haploid (DH) population segregating for common bunt resistance was used to identify the chromosomal location of common bunt resistance gene Bt9. DH lines were phenotyped in three environments and genotyped with DArTseq and SSR markers. The total length of the resulting linkage map was 2882 cM distributed across all 21 wheat chromosomes. Bt9 was mapped to the distal end of chromosome 6DL. Since wheat common bunt resistance gene Bt10 is also located on chromosome 6D, the possibility of their co-location was investigated. A comparison of marker sequences linked to Bt9 and Bt10 on physical maps of chromosome 6D confirmed that Bt9 and Bt10 are two distinct resistance factors located at the distal (6DL) and proximal (6DS) end, respectively, of chromosome 6D. Five new SSR markers Xgpw4005-1, Xgpw7433, Xwmc773, Xgpw7303 and Xgpw362 and many SNP and PAV markers flanking the Bt9 resistance locus were identified and they may be used in the future for marker-assisted selection.

Seed Production Affects Maternal Growth and Senescence in Arabidopsis.

Correlative control (influence of one organ over another organ) of seeds over maternal growth is one of the most obvious phenotypic expressions of the trade-off between growth and reproduction. However, the underlying molecular mechanisms are largely unknown. Here, we characterize the physiological and molecular effects of correlative inhibition by seeds on Arabidopsis (Arabidopsis thaliana) inflorescences, i.e. global proliferative arrest (GPA) during which all maternal growth ceases upon the production of a given number of seeds. We observed transcriptional responses to growth- and branching-inhibitory hormones, and low mitotic activity in meristems upon GPA, but found that meristems retain their identity and proliferative potential. In shoot tissues, we detected the induction of stress- and senescence-related gene expression upon fruit production and GPA, and a drop in chlorophyll levels, suggestive of altered source-sink relationships between vegetative shoot and reproductive tissues. Levels of shoot reactive oxygen species, however, strongly decreased upon GPA, a phenomenon that is associated with bud dormancy in some perennials. Indeed, gene expression changes in arrested apical inflorescences after fruit removal resembled changes observed in axillary buds following release from apical dominance. This suggests that GPA represents a form of bud dormancy, and that dominance is gradually transferred from growing inflorescences to maturing seeds, allowing offspring control over maternal resources, simultaneously restricting offspring number. This would provide a mechanistic explanation for the constraint between offspring quality and quantity.

Lesion formation after pulmonary vein isolation using the advance cryoballoon and the standard cryoballoon: lessons learned from late gadolinium enhancement magnetic resonance imaging.

AIMS: To compare ablation lesion formation after pulmonary vein isolation (PVI) using the standard cryoballoon (CB-S) vs. the re-designed cryoballoon Arctic Front Advance (CB-A) using late gadolinium enhancement magnetic resonance imaging (LGE-MRI) 3 months post-ablation. METHODS AND RESULTS: Thirty-six consecutive patients with paroxysmal or short-lasting persistent atrial fibrillation (AF) were evaluated prospectively after PVI using the CB-S in the first 18 patients and the CB-A in the subsequent 18 patients. All patients underwent LGE-MRI and a 7-day Holter electrocardiogram monitoring 3 months after ablation. Fifty-six per cent of the patients were male (mean age 63.0 ± 9.1 years). Fifty-six per cent in the first group and 89% in the second group were free of AF recurrence 3 months after ablation (P = 0.025). Three months after ablation, LGE-MRI of the left atrium showed complete circular lesions in 35% of PVs in the first group and in 32% of PVs in the second group (n.s.). The left PVs showed a significantly higher proportion of PV segments with complete ablation lesions compared with the right PVs (83 vs. 34%; P < 0.001). CONCLUSION: Cardiac MRI is able to visualize induced ablation lesions after PVI and might be suitable to quantify ablation lesion amount. Ablation lesion formation did not differ significantly in patients treated with the CB-S vs. the CB-A, despite a significantly lower rate of AF recurrence after 3 months in the CB-A group. Left PVs showed a significantly higher amount of ablation lesions compared with the right PVs. Larger and randomized studies are needed to understand the relationship between representable tissue lesions and success rates.

The cytosolic thiouridylase CTU2 of Arabidopsis thaliana is essential for posttranscriptional thiolation of tRNAs and influences root development.

BACKGROUND: A large number of post-transcriptional modifications of transfer RNAs (tRNAs) have been described in prokaryotes and eukaryotes. They are known to influence their stability, turnover, and chemical/physical properties. A specific subset of tRNAs contains a thiolated uridine residue at the wobble position to improve the codon-anticodon interaction and translational accuracy. The proteins involved in tRNA thiolation are reminiscent of prokaryotic sulfur transfer reactions and of the ubiquitylation process in eukaryotes. In plants, some of the proteins involved in this process have been identified and show a high degree of homology to their non-plant equivalents. For other proteins, the identification of the plant homologs is much less clear, due to the low conservation in protein sequence. RESULTS: This manuscript describes the identification of CTU2, the second CYTOPLASMIC THIOURIDYLASE protein of Arabidopsis thaliana. CTU2 is essential for tRNA thiolation and interacts with ROL5, the previously identified CTU1 homolog of Arabidopsis. CTU2 is ubiquitously expressed, yet its activity seems to be particularly important in root tissue. A ctu2 knock-out mutant shows an alteration in root development. CONCLUSIONS: The analysis of CTU2 adds a new component to the so far characterized protein network involved in tRNA thiolation in Arabidopsis. CTU2 is essential for tRNA thiolation as a ctu2 mutant fails to perform this tRNA modification. The identified Arabidopsis CTU2 is the first CTU2-type protein from plants to be experimentally verified, which is important considering the limited conservation of these proteins between plant and non-plant species. Based on the Arabidopsis protein sequence, CTU2-type proteins of other plant species can now be readily identified.

Ubiquitin-related modifiers of Arabidopsis thaliana influence root development.

Ubiquitins are small peptides that allow for posttranslational modification of proteins. Ubiquitin-related modifier (URM) proteins belong to the class of ubiquitin-like proteins. A primary function of URM proteins has been shown to be the sulfur transfer reaction leading to thiolation of tRNAs, a process that is important for accurate and effective protein translation. Recent analyses revealed that the Arabidopsis genome codes for two URM proteins, URM11 and URM12, which both are active in the tRNA thiolation process. Here, we show that URM11 and URM12 have overlapping expression patterns and are required for tRNA thiolation. The characterization of urm11 and urm12 mutants reveals that the lack of tRNA thiolation induces changes in general root architecture by influencing the rate of lateral root formation. In addition, they synergistically influence root hair cell growth. During the sulfur transfer reaction, URM proteins of different organisms interact with a thiouridylase, a protein-protein interaction that also takes place in Arabidopsis, since URM11 and URM12 interact with the Arabidopsis thiouridylase ROL5. Hence, the sulfur transfer reaction is conserved between distantly related species such as yeast, humans, and plants, and in Arabidopsis has an impact on root development.