Effects of deoxynivalenol (DON), zearalenone (ZEN), and related metabolites on equine peripheral blood mononuclear cells (PBMC) in vitro and background occurrence of these toxins in horses

Both deoxynivalenol (DON), zearalenone (ZEN), and their metabolites are known to modulate immune cells in various species whereby viability and proliferation are influenced. Such effects were rarely examined in horses. Therefore, one aim of the present study was to titrate the inhibitory concentrations of DON, 3-acetyl-DON (3AcDON), de-epoxy-DON (DOM-1), ZEN, and α- and β-zearalenol (ZEL) at which viability and proliferation of equine PBMC were reduced by 50 % (IC₅₀) and 10 % (IC₁₀) in vitro. For evaluation of practical relevance of the in vitro findings, a further aim was to screen horses for the background occurrence of DON, ZEN, and their metabolites in systemic circulation and to relate toxin residues both to the inhibitory toxin concentrations and to hematological and clinical-chemical characteristics.The IC₅₀ (μM) for DON, 3AcDON, β-ZEL, α-ZEL, and ZEN were determined at 3.09, 25.90, 75.44, 97.44, and 98.15 in unstimulated cells, respectively, while in proliferating cells, the corresponding IC₅₀ values were 0.73, 6.89, 45.16, 75.96, and 82.51. Neither viability nor proliferation was influenced by DOM-1 up to a concentration of 100 μM.The in vivo screening (N?=?49) revealed the occurrence of ZEN (N?=?24), α-ZEL (N?=?3), β-ZEL (N?=?37), DON, and DOM-1 (N?=?2). The detected concentrations were much lower than the corresponding IC₅₀ while the IC₁₀ of DON and β-ZEL for proliferating PBMC corresponded to approximately 26 and 35 ng/mL which might be relevant when contaminated diets are fed.Clinical-chemical and hematological traits were not related to mycotoxin residue levels excepting blood urea nitrogen which was positively correlated to the sum of β-ZEL, α-ZEL, and ZEN concentration. Whether this reflects simply the feeding history of the horses or renal failures giving rise to a prolonged half-life of the toxins needs to be clarified further.     

Gatekeeper role of brain antigen‐presenting CD11c+ cells in neuroinflammation

Multiple sclerosis is the most frequent chronic inflammatory disease of the CNS. The entry and survival of pathogenic T cells in the CNS are crucial for the initiation and persistence of autoimmune neuroinflammation. In this respect, contradictory evidence exists on the role of the most potent type of antigen‐presenting cells, dendritic cells. Applying intravital two‐photon microscopy, we demonstrate the gatekeeper function of CNS professional antigen‐presenting CD11c⁺ cells, which preferentially interact with Th17 cells. IL‐17 expression correlates with expression of GM‐CSF by T cells and with accumulation of CNS CD11c⁺ cells. These CD11c⁺ cells are organized in perivascular clusters, targeted by T cells, and strongly express the inflammatory chemokines Ccl5, Cxcl9, and Cxcl10. Our findings demonstrate a fundamental role of CNS CD11c⁺ cells in the attraction of pathogenic T cells into and their survival within the CNS. Depletion of CD11c⁺ cells markedly reduced disease severity due to impaired enrichment of pathogenic T cells within the CNS.     

Genetic Manipulation of Glycogen Allocation Affects Replicative Lifespan in E. coli

In bacteria, replicative aging manifests as a difference in growth or survival between the two cells emerging from division. One cell can be regarded as an aging mother with a decreased potential for future survival and division, the other as a rejuvenated daughter. Here, we aimed at investigating some of the processes involved in aging in the bacterium Escherichia coli, where the two types of cells can be distinguished by the age of their cell poles. We found that certain changes in the regulation of the carbohydrate metabolism can affect aging. A mutation in the carbon storage regulator gene, csrA, leads to a dramatically shorter replicative lifespan; csrA mutants stop dividing once their pole exceeds an age of about five divisions. These old-pole cells accumulate glycogen at their old cell poles; after their last division, they do not contain a chromosome, presumably because of spatial exclusion by the glycogen aggregates. The new-pole daughters produced by these aging mothers are born young; they only express the deleterious phenotype once their pole is old. These results demonstrate how manipulations of nutrient allocation can lead to the exclusion of the chromosome and limit replicative lifespan in E. coli, and illustrate how mutations can have phenotypic effects that are specific for cells with old poles. This raises the question how bacteria can avoid the accumulation of such mutations in their genomes over evolutionary times, and how they can achieve the long replicative lifespans that have recently been reported.     

Mitochondrial implications in human pregnancies with intrauterine growth restriction and associated cardiac remodelling

Intrauterine growth restriction (IUGR) is an obstetric complication characterised by placental insufficiency and secondary cardiovascular remodelling that can lead to cardiomyopathy in adulthood. Despite its aetiology and potential therapeutics are poorly understood, bioenergetic deficits have been demonstrated in adverse foetal and cardiac development. We aimed to evaluate the role of mitochondria in human pregnancies with IUGR. In a single‐site, cross‐sectional and observational study, we included placenta and maternal peripheral and neonatal cord blood mononuclear cells (PBMC and CBMC) from 14 IUGR and 22 control pregnancies. The following mitochondrial measurements were assessed: enzymatic activities of mitochondrial respiratory chain (MRC) complexes I, II, IV, I + III and II + III, oxygen consumption (cell and complex I‐stimulated respiration), mitochondrial content (citrate synthase [CS] activity and mitochondrial DNA copy number), total ATP levels and lipid peroxidation. Sirtuin3 expression was evaluated as a potential regulator of bioenergetic imbalance. Intrauterine growth restriction placental tissue showed a significant decrease of MRC CI enzymatic activity (P < 0.05) and CI‐stimulated oxygen consumption (P < 0.05) accompanied by a significant increase of Sirtuin3/β‐actin protein levels (P < 0.05). Maternal PBMC and neonatal CBMC from IUGR patients presented a not significant decrease in oxygen consumption (cell and CI‐stimulated respiration) and MRC enzymatic activities (CII and CIV). Moreover, CS activity was significantly reduced in IUGR new‐borns (P < 0.05). Total ATP levels and lipid peroxidation were preserved in all the studied tissues. Altered mitochondrial function of IUGR is especially present at placental and neonatal level, conveying potential targets to modulate obstetric outcome through dietary interventions aimed to regulate Sirtuin3 function.     

Proteogenomic Refinement of the Neomegalonema perideroedesT Genome Annotation

Neomegalonema perideroedes (formerly Meganema perideroedes) str. G1 is the type strain and only described isolate of the genus Neomegalonema (formerly Meganema) which belongs to the Alphaproteobacteria. N. perideroedes is distinguished by the ability to accumulate high amounts of polyhydroxyalkanoates and has been associated with bulking problems in wastewater treatment plants due to its filamentous morphology. In 2013, its genome was sequenced as part of the Genomic Encyclopedia of Bacteria and Archaea (GEBA), which aims to improve the sequencing coverage of the poorly represented regions of the bacterial and archaeal branches of the tree of life. As N. perideroedes str. G1 is relatively distantly related to well described species—being the only sequenced member of its proposed family—the in silico prediction of genes by nucleotide homology to reference genes might be less reliable. Here, a proteomic dataset for the refinement of the N. perideroedes genome annotations is generated which clearly indicates the shortcomings of high‐throughput in silico genome annotation.     

MobiSeq: De novo SNP discovery in model and non‐model species through sequencing the flanking region of transposable elements

In recent years, the availability of reduced representation library (RRL) methods has catalysed an expansion of genome‐scale studies to characterize both model and non‐model organisms. Most of these methods rely on the use of restriction enzymes to obtain DNA sequences at a genome‐wide level. These approaches have been widely used to sequence thousands of markers across individuals for many organisms at a reasonable cost, revolutionizing the field of population genomics. However, there are still some limitations associated with these methods, in particular the high molecular weight DNA required as starting material, the reduced number of common loci among investigated samples, and the short length of the sequenced site‐associated DNA. Here, we present MobiSeq, a RRL protocol exploiting simple laboratory techniques, that generates genomic data based on PCR targeted enrichment of transposable elements and the sequencing of the associated flanking region. We validate its performance across 103 DNA extracts derived from three mammalian species: grey wolf (Canis lupus), red deer complex (Cervus sp.) and brown rat (Rattus norvegicus). MobiSeq enables the sequencing of hundreds of thousands loci across the genome and performs SNP discovery with relatively low rates of clonality. Given the ease and flexibility of MobiSeq protocol, the method has the potential to be implemented for marker discovery and population genomics across a wide range of organisms—enabling the exploration of diverse evolutionary and conservation questions.     

Serum tau fragments as predictors of death or poor neurological outcome after out-of-hospital cardiac arrest

Background: Anoxic brain injury is the primary cause of death after resuscitation from out-of-hospital cardiac arrest (OHCA) and prognostication is challenging. The aim of this study was to evaluate the potential of two fragments of tau as serum biomarkers for neurological outcome.

Methods: Single-center sub-study of 171 patients included in the Target Temperature Management (TTM) Trial randomly assigned to TTM at 33?°C or TTM at 36?°C for 24?h after OHCA. Fragments (tau-A and tau-C) of the neuronal protein tau were measured in serum 24, 48 and 72?h after OHCA. The primary endpoint was neurological outcome.

Results: Median (quartile 1 – quartile 3) tau-A (ng/ml) values were 58 (43–71) versus 51 (43–67), 72 (57–84) versus 71 (59–82) and 76 (61–92) versus 75 (64–89) for good versus unfavourable outcome at 24, 48 and 72?h, respectively (p_group = 0.95). Median tau C (ng/ml) values were 38 (29–50) versus 36 (29–49), 49 (38–58) versus 48 (33–59) and 48 (39–59) versus 48 (36–62) (p_group = 0.95). Tau-A and tau-C did not predict neurological outcome (area under the receiver-operating curve at 48?h; tau-A: 0.51 and tau-C: 0.51).

Conclusions: Serum levels of tau fragments were unable to predict neurological outcome after OHCA.