Interaction of minerals,organic matter,and microorganisms during biogeochemical interface formation as shown by a series of artificial soil experiments

Our understanding of the interactions between minerals, organic matter, and microorganisms at so-called biogeochemical interfaces in soil is still hampered by the inherent complexity of these systems. Artificial soil maturation experiments can help to bridge a gap in complexity between simple abiotic sorption experiments and larger-scale field experiments. By controlling other soil-forming factors, the effect of a particular variable can be identified in a simplified system. Here, we review the findings of a series of artificial soil incubation experiments with the aim of revealing general trends and conclusions. The artificial soils were designed to determine the effect of mineral composition and charcoal presence on the development of abiotic and biotic soil properties during maturation. In particular, the development of soil aggregates, organic matter (OM) composition and turnover, sorption properties, and the establishment of microbial community composition and function were considered. The main objectives of the research were to determine (1) how surface properties and sorption of chemicals modify biogeochemical interfaces; (2) how much time is required to form aggregates from mixtures of pure minerals, OM, and a microbial inoculum; and (3) how the presence of different mineral and charcoal surfaces affects aggregation, OM turnover, and the development of microbial community composition.     

Canine oral primary melanoma cells exhibit shift to mesenchymal phenotype and phagocytic behaviour

Canine oral malignant melanoma (COMM) is a potentially lethal cancer disease. We established primary cell lines from mostly amelanotic primary COMM and metastases and assessed lesions and derived cells for Melan A, PNL2 and CD146 expression. Then, migration and invasion of CD146‐enriched vs ‐depleted COMM cells were analysed. Epithelial‐to‐mesenchymal transition (EMT) was addressed by Vimentin‐staining and MMP2/MMP9 zymography. Phagocytic behaviour was analysed by histopathological examination and phagocytosis assay. While Melan A‐ and PNL2‐staining yielded inconsistent data, 100% of COMM sections and primary cells showed CD146 expression, suggesting that this protein may serve as a prognostic marker. An overall correlation between CD146‐expression and migration/invasion was not observed. All primary cell lines consistently expressed Vimentin and secreted biologically active MMP2, indicating that they had undergone EMT. Importantly, COMM sections exhibited cell‐in‐cell structures, and all primary cell lines exhibited phagocytic activity, supporting the concept that cell cannibalism may have a role in COMM progression.     

Absence Seizures as a Feature of Juvenile Myoclonic Epilepsy in Rhodesian Ridgeback Dogs

Myoclonic epilepsy in Rhodesian Ridgeback (RR) dogs is characterized by myoclonic seizures occurring mainly during relaxation periods, a juvenile age of onset and generalized tonic‐clonic seizures in one‐third of patients. An 8‐month‐old female intact RR was presented for myoclonic seizures and staring episodes that both started at 10 weeks of age. Testing for the DIRAS1 variant indicated a homozygous mutant genotype. Unsedated wireless video‐electroencephalography (EEG) identified frequent, bilaterally synchronous, generalized 4 Hz spike‐and‐wave complexes (SWC) during the staring episodes in addition to the characteristic myoclonic seizures with generalized 4–5 Hz SWC or 4–5 Hz slowing. Photic stimulation did not evoke a photoparoxysmal response. Repeat video‐EEG 2 months after initiation of levetiracetam treatment disclosed a >95% decrease in frequency of myoclonic seizures, and absence seizures were no longer evident. Absence seizures represent another seizure type in juvenile myoclonic epilepsy (JME) in RR dogs, which reinforces its parallels to JME in humans.     

Counting of single prion particles bound to a capture-antibody surface (surface-FIDA)

Hitherto accredited prion tests use the PK resistance of PrP(Sc), the pathogenic isoform of the prion protein, as a marker for the disease. Because of variations in the amount of disease-related aggregated PrP, which is not PK-resistant, these prion tests offer only limited sensitivity. Therefore, a prion detection method that does not rely on PK digestion would allow for the detection of both PK-resistant as well as PK-sensitive PrP(Sc). Furthermore, single particle counting is more sensitive than methods measuring an integrated signal. Our new test system is based on dual-colour fluorescence correlation spectroscopy (FCS). This method quantifies the number of protein aggregates that have been simultaneously labelled with two different antibodies using dual-colour fluorescence intensity distribution analysis (2D-FIDA). This only counts PrP aggregates, and not PrP monomers. To increase the sensitivity, PrP(Sc) was concentrated in a two-dimensional space by immobilizing it so that the antibodies could be captured on the surface of the slide (surface-FIDA). When the surface was systematically scanned, even single prion particles were detected. Using this new technique, the sensitivity to identify samples from scrapie-infected hamster as well as BSE-infected cattle can be dramatically increased in comparison with identification using FIDA in solution.     

Comparison of bread wheat varieties with different breeding origin under organic and low input management

In recent years needs have increased to investigate the necessity of breeding cereals for organic agriculture. The aims of this study were (1) to compare 37 bread wheat (Triticum aestivum L.) varieties with different breeding origin under low input conventional and certified organic farming conditions in Austria and Hungary for 3 years, (2) to identify traits highly sensitive to management systems that could be separated according to their suggested selecting environments and (3) to find evidence for the distinctness of organic wheat breeding. According to the results, seven out of the 15 traits assessed during this study showed significant management × genotype interaction meaning that these traits could be the basis of selection for different management systems. Heading date, sensitivity to leaf rust and powdery mildew had high repeatabilities. For economic reasons, it is therefore reasonable to select for these traits in conventional fields even if the selection target is organic agriculture. However, the present study suggests that selection for the other four traits (grain yield, test weight, leaf-inclination and vigorous growth during booting) should be done later in the target environment. The study compared groups of varieties developed by different breeding strategies (organic, conventional and combined strategies). The results of multivariate analyses showed that the organic breeding was distinct from the other two breeding strategies, but the combined and conventional breeding resulted in similar groupings. It is concluded that the selecting environment has measurable effects on the performance of bread wheat varieties under organic and low input growing conditions.     

Mitigating the impact of selective phenotyping in training populations on the prediction ability by multi-trait pedigree and genomic selection models

Training populations for pedigree and genomic prediction in plant breeding programmes are largely updated with superior genotypes from multi-environment trials, where they are tested with the goal of variety development. Such a selective phenotyping has, however, a negative impact on prediction abilities, especially when only a subset of breeding lines can be tested, as for laborious and costly to phenotype traits. This study focused, thus, on investigating the impact of selective phenotyping in the training population of an applied wheat breeding programme, and assessing the potential to mitigate this impact by pedigree and genomic multi-trait prediction models as well as bi-directionally selected training populations for several baking quality parameters. Combining both pedigree and genomic information in multi-trait prediction models with pre-existing phenotypic information for protein content and sedimentation value compensated for the observed loss in prediction ability, while entering few inferior breeding lines into the training population further mitigated the impact of selective phenotyping and even led to a slight increase of prediction ability in comparison to a randomly chosen training population.     

Rhodesian Ridgebacks have an increased risk to develop benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is an age-dependent primarily non-inflammatory enlargement of the accessory gland in the intact dog. The aim of the present study was to control a previously raised suspicion of a breed-related higher incidence of BPH in dogs of the Rhodesian Ridgeback breed. For this, 18 Labrador Retrievers/LR and 20 Rhodesian Ridgebacks/RR were assigned to the age groups 18–24 months (n = 12), 25–48 months (n = 13) and 49–72 months (n = 13). Prostate gland status was determined by rectal palpation, B-mode ultrasound, calculation of the prostate gland volume and semen analysis regarding haemospermia and was classified according to blood plasma concentrations of canine prostate-specific arginine esterase (CPSE) (normal ≤ 60 ng/ml, increased ≥ 61 ng/ml; Pinheiro et al., 2017). Concentrations of testosterone, 5α-dihydrotestosterone and estradiol were analysed in peripheral blood serum or plasma for detecting breed-specific conditions regarding the endocrine metabolism. Prostatic volume was significantly larger in RR irrespective of the CPSE status. In RR, BPH occurred more frequently and started at an earlier age compared with the LR. Breed-related specificities in steroid metabolism in the RR were indicated by correlations of 5α-dihydrotestosterone and estradiol with age and of testosterone with prostate gland volume. Although the incidence of sonographic signs of BPH and haemospermia did not fit with normal and increased CPSE concentrations, a breed-specific higher incidence of BPH in the RR breed could be clearly verified.     

Thermally induced degradation of sulfur-containing aliphatic glucosinolates in broccoli sprouts (Brassica oleracea var. italica) and model systems

Processing reduces the glucosinolate (GSL) content of plant food, among other aspects due to thermally induced degradation. Since there is little information about the thermal stability of GSL and formation of corresponding breakdown products, the thermally induced degradation of sulfur-containing aliphatic GSL was studied in broccoli sprouts and with isolated GSL in dry medium at different temperatures as well as in aqueous medium at different pH values. Desulfo-GSL have been analyzed with HPLC-DAD, while breakdown products were estimated using GC-FID. Whereas in the broccoli sprouts structural differences of the GSL with regard to thermal stability exist, the various isolated sulfur-containing aliphatic GSL degraded nearly equally and were in general more stable. In broccoli sprouts, methylsulfanylalkyl GSL were more susceptible to degradation at high temperatures, whereas methylsulfinylalkyl GSL were revealed to be more affected in aqueous medium under alkaline conditions. Besides small amounts of isothiocyanates, the main thermally induced breakdown products of sulfur-containing aliphatic GSL were nitriles. Although they were most rapidly formed at comparatively high temperatures under dry heat conditions, their highest concentrations were found after cooking in acidic medium, conditions being typical for domestic processing.