37 research outputs found
Alternatives to Mineral Oil Adjuvants in Vaccines Against <i>Aeromonas salmonicida</i> subs. <i>salmonicida </i>in Rainbow Trout Offer Reductions in Adverse Effects
publishedVersio
Characterisation of MSWI bottom ash for potential use as subbase in Greenlandic road construction
Quinolone Resistance in Gallibacterium anatis Determined by Mutations in Quinolone Resistance-Determining Region.
Control of the important pathogen, Gallibacterium anatis, which causes salpingitis and peritonitis in poultry, relies on treatment using antimicrobial compounds. Among these, quinolones and fluoroquinolones have been used extensively, leading to a rise in the prevalence of resistant strains. The molecular mechanisms leading to quinolone resistance, however, have not previously been described for G. anatis, which is the aim of this study. The present study combines phenotypic antimicrobial resistance data with genomic sequence data from a collection of G. anatis strains isolated from avian hosts between 1979 and 2020. Minimum inhibitory concentrations were determined for nalidixic acid, as well as for enrofloxacin for each included strain. In silico analyses included genome-wide queries for genes known to convey resistance towards quinolones, identification of variable positions in the primary structure of quinolone protein targets and structural prediction models. No resistance genes known to confer resistance to quinolones were identified. Yet, a total of nine positions in the quinolone target protein subunits (GyrA, GyrB, ParC and ParE) displayed substantial variation and were further analyzed. By combining variation patterns with observed resistance patterns, positions 83 and 87 in GyrA, as well as position 88 in ParC, appeared to be linked to increased resistance towards both quinolones included. As no notable differences in tertiary structure were observed between subunits of resistant and sensitive strains, the mechanism behind the observed resistance is likely due to subtle shifts in amino acid side chain properties
Citrus flavonoids, β-Glucan and organic acid feed additives decrease relative risk during<i> Yersinia ruckeri </i>O1 biotype 2 infection of rainbow trout (<i>Oncorhynchus mykiss</i>)
Injection vaccines formulated with nucleotide, liposomal or mineral oil adjuvants induce distinct differences in immunogenicity in rainbow trout
Protection facilitated by the widespread use of mineral oil adjuvanted injection vaccines in salmonid fish comes with adverse effects of varying severity. In this study, we characterized the immunological profiles of two alternative vaccine formulations, both with proven efficacy and an improved safety profile in rainbow trout. Experimental injection vaccines were prepared on an identical whole-cell Aeromonas salmonicida bacterin platform and were formulated with CpG oligodeoxynucleotides, a liposomal (CAF01) or a benchmark mineral oil adjuvant, respectively. A naïve group, as well as bacterin and saline-injected groups were also included. Following administration, antigen-specific serum antibody titers, the tissue distribution of immune cell markers, and the expression of immune-relevant genes following the in vitro antigenic restimulation of anterior kidney leukocytes was investigated. Immunohistochemical staining suggested prolonged antigen presentation for the particulate formulations and increased mucosal presence of antigen-presenting cells in all immunized fish. Unlike the other immunized groups, the CAF01 group only displayed a transient elevation in specific antibody titers and immunohistochemical observations, and the transcription data suggest an increased role of cell-mediated immunity for this group. Finally, the transcription profile of the CpG formulation approached that of a TH1 profile. When compared to the benchmark formulation, CAF01 and CpG adjuvants induce slight, but distinct differences in the resulting protective immune responses. This is important, as it allows a broader immunological approach for the future development of safer vaccines.publishedVersio
Q Fever in Greenland
We report a patient with Q fever endocarditis in a settlement in eastern Greenland (Isortoq, Ammassalik area). Likely animal sources include sled dogs and seals. Q fever may be underdiagnosed in Arctic areas but may also represent an emerging infection
Genome-resolved metagenomics suggests a mutualistic relationship between Mycoplasma and salmonid hosts
Salmonids are important sources of protein for a large proportion of the human population. Mycoplasma species are a major constituent of the gut microbiota of salmonids, often representing the majority of microbiota. Despite the frequent reported dominance of salmonid-related Mycoplasma species, little is known about the phylogenomic placement, functions and potential evolutionary relationships with their salmonid hosts. In this study, we utilise 2.9 billion metagenomic reads generated from 12 samples from three different salmonid host species to I) characterise and curate the first metagenome-assembled genomes (MAGs) of Mycoplasma dominating the intestines of three different salmonid species, II) establish the phylogeny of these salmonid candidate Mycoplasma species, III) perform a comprehensive pangenomic analysis of Mycoplasma, IV) decipher the putative functionalities of the salmonid MAGs and reveal specific functions expected to benefit the host. Our data provide a basis for future studies examining the composition and function of the salmonid microbiota
The stellar content of the XMM-Newton Bright Serendipitous Survey
Context: The comparison of observed counts in a given sky direction with
predictions by Galactic models yields constraints to the spatial distribution
and the stellar birthrate of young stellar populations. In this work we present
the results of the analysis of the stellar content of the XMM-Newton Bright
Serendipitous Survey (XBSS). This unbiased survey includes a total of 58
stellar sources selected in the 0.5 -- 4.5 keV energy band, having a limiting
sensitivity of cnt s and covering an area of 28.10 sq. deg.
Aims: Our main goal is to understand the recent star formation history of the
Galaxy in the vicinity of the Sun. Methods: We compare the observations with
the predictions obtained with XCOUNT, a model of the stellar X-ray content of
the Galaxy. The model predicts the number and properties of the stars to be
observed in terms of magnitude, colour, population and
ratio distributions of the coronal sources detected
with a given instrument and sensitivity in a specific sky direction. Results:
As in other shallow surveys, we observe an excess of stars not predicted by our
Galaxy model. Comparing the colours of the identified infrared counterparts
with the model predictions, we observe that this excess is produced by yellow
(G+K) stars. The study of the X-ray spectrum of each source reveals a main
population of stars with coronal temperature stratification typical of
intermediate-age stars. As no assumptions have been made for the selection of
the sample, our results must be representative of the entire Solar
Neighbourhood. Some stars show excess circumstellar absorption indicative of
youth.Comment: Accepted for publication in Astronomy and Astrophysics: 02/10/200