Evolution of major histocompatibility complex class I and class II genes in the brown bear

International audienceBackground: Major histocompatibility complex (MHC) proteins constitute an essential component of the vertebrate immune response, and are coded by the most polymorphic of the vertebrate genes. Here, we investigated sequence variation and evolution of MHC class I and class II DRB, DQA and DQB genes in the brown bear Ursus arctos to characterise the level of polymorphism, estimate the strength of positive selection acting on them, and assess the extent of gene orthology and trans-species polymorphism in Ursidae . Results: We found 37 MHC class I, 16 MHC class II DRB, four DQB and two DQA alleles. We confirmed the expression of several loci: three MHC class I, two DRB, two DQB and one DQA. MHC class I also contained two clusters of non-expressed sequences. MHC class I and DRB allele frequencies differed between northern and southern populations of the Scandinavian brown bear. The rate of nonsynonymous substitutions (d N ) exceeded the rate of synonymous substitutions (d S ) at putative antigen binding sites of DRB and DQB loci and, marginally significantly, at MHC class I loci. Models of codon evolution supported positive selection at DRB and MHC class I loci. Both MHC class I and MHC class II sequences showed orthology to gene clusters found in the giant panda Ailuropoda melanoleuca. Conclusions: Historical positive selection has acted on MHC class I, class II DRB and DQB, but not on the DQA locus. The signal of historical positive selection on the DRB locus was particularly strong, which may be a general feature of caniforms. The presence of MHC class I pseudogenes may indicate faster gene turnover in this class through the birth-and-death process. South - north population structure at MHC loci probably reflects origin of the populations from separate glacial refugia

Streptococcus suis in invasive human infections in Poland : clonality and determinants of virulence and antimicrobial resistance

The purpose of this study was to perform an analysis of Streptococcus suis human invasive isolates, collected in Poland by the National Reference Centre for Bacterial Meningitis. Isolates obtained from 21 patients during 2000–2013 were investigated by phenotypic tests, multilocus sequence typing (MLST), analysis of the TR9 locus from the multilocus variable number tandem repeat (VNTR) analysis (MLVA) scheme and pulsed-field gel electrophoresis (PFGE) of SmaI-digested DNA. Determinants of virulence and antimicrobial resistance were detected by polymerase chain reaction (PCR) and analysed by sequencing. All isolates represented sequence type 1 (ST1) and were suggested to be serotype 2. PFGE and analysis of the TR9 locus allowed the discrimination of four and 17 types, respectively. Most of the isolates were haemolysis- and DNase-positive, and around half of them formed biofilm. Genes encoding suilysin, extracellular protein factor, fibronectin-binding protein, muramidase-released protein, surface antigen one, enolase, serum opacity factor and pili were ubiquitous in the studied group, while none of the isolates carried sequences characteristic for the 89K pathogenicity island. All isolates were susceptible to penicillin, cefotaxime, imipenem, moxifloxacin, chloramphenicol, rifampicin, gentamicin, linezolid, vancomycin and daptomycin. Five isolates (24 %) were concomitantly non-susceptible to erythromycin, clindamycin and tetracycline, and harboured the tet(O) and erm(B) genes; for one isolate, lsa(E) and lnu(B) were additionally detected. Streptococcus suis isolated in Poland from human invasive infections belongs to a globally distributed clonal complex of this pathogen, enriched in virulence markers. This is the first report of the lsa(E) and lnu(B) resistance genes in S. suis. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10096-016-2616-x) contains supplementary material, which is available to authorized users

Effectiveness of different types of hair traps for brown bear research and monitoring

Non-invasive sampling by hair-trapping is increasingly used worldwide in wildlife research. Despite this rise and the potential of hair samples for ecology and conservation studies, the relative performance of hair collection devices has been rarely tested. Here, we compare the effectiveness of five types of hair traps for brown bears Ursus arctos in the Carpathian Mountains (SE Poland) and test the effects of trap type, season, number of days elapsed since trap installation and trap features on the trapping success in order to provide recommendations for optimal sampling in future studies. The trap types were corral, path-trap, "smola"(beechwood tar) tree-trap, turpentine tree-trap and natural rub. In 2010, we collected 858 hair samples during 2330 inspections of 175 hair traps and found that the most effective traps were smola tree-traps (mean percentage of successful inspections ± SD: 30.2% ± 26.0) and natural rubs (50.8% ± 16.7). Based on this finding, over the following 2 years we focused on 24 smola tree-traps and eight natural rubs. During this long-term survey (2010-2012, 969 inspections, 1322 samples collected) the trapping success increased with time and smola tree-traps achieved similar effectiveness to natural rubs (45.5% ± 29.7 and 45.9 ± 23.4, respectively). We show that when baiting smola tree-traps ten weeks prior to research or monitoring, sampling effectiveness can reach up to 30%. Taking into account the logistical and methodological constraints associated with detecting and using natural rubs for a proper survey design, we recommend using smola tree-traps baited in advance for hair sampling in wildlife studies

Tie-2 expressing monocytes in chronic lymphocytic leukemia

IntroductionIn peripheral blood, monocytes form a heterogeneous population of cells. One particular subset of circulating monocytes is expressing the angiopoietin receptor Tie-2 (Tie2-expressing monocyte; TEM). TEM are characterized by tumor promoting properties. However, the role of TEM in chronic lymphocytic leukemia (CLL) immunopathogenesis remains undefined.Material and MethodsHere, we evaluated the monocytes with Tie-2 expression (CD14+Tie-2+) in peripheral blood of CLL patients (n=55) and normal subjects (n=15) by flow cytometry. We investigated possible associations between TEM and poor prognostic factors such as CD38 or ZAP-70 expression, Rai stage and unfavorable cytogenetic abnormalities. Moreover, we investigated the association of TEM percentage with CD14++CD16+ monocytes and Treg percentages.ResultsWe found that CLL patients had a higher percentage of CD14+Tie-2+ monocytes compared to normal controls. The percentage of TEM was positively associated with ZAP-70 expression as well as with unfavourable cytogenetic changes: del(17p) and/or del(11q). The frequency of TEM increased with the disease stage. We showed no correlation between the percentage of TEM and CD38 expression. The percentage of TEM at diagnosis was associated with white blood cell count as well as with the percentages of CD19+CD5+ lymphocytes and Tregs. The majority of CD14+Tie-2+ cells belonged to the intermediate monocytes subset (CD14++CD16+) while fewer of them were among the classical (CD14++CD16−) or non-classical monocyte (CD14+CD16++) subsets. TEM and CD14++CD16+ monocytes have a proangiogenic activity, suppress T-cell activation and promote Treg expansion. The results suggest that monitoring of TEM number and function may provide useful information in determining disease activity

Social e-atmospherics in practice (or not): a French and Turkish web designers’ perspectives

Little is known about the development of social e- atmospherics. And yet, e-atmospherics havemotivated an emerging body of research which reports that both better layouts and‘recognized’ atmospherics encourage consumers to modify their shopping habits. While the literature has analyzed mainly the functional (design) aspect of e-atmospherics, little has been done in terms of linking its characteristics’ to social (co-) creation. This paper attempts to redress the imbalance by exploring the anatomy from a website designer perspective of the social dimension of design in relation to e-atmospherics, which includes factors such as the aesthetic design of space and the influence of visual cues as a socially constructed meaning. We identify the challenges that web designers as social agents, who interact within intangible social reference sets, restricted by social standards, value, beliefs, status and duties, face daily within their work. We aim to review the current understanding of the importance and voluntary integration of social cues displayed by web designers from a mature market and an emerging market, and provides an analysis based recommendation towards the development of an integrated e-social atmospheric framework. Results report exploratory findings from questionnaires with 10 French and 16 Turkish web designers. These allow us to re-interpret the web designers’ reality regarding social e-atmospherics. We contend that by comprehending (before any consumer/client input) social capital, daily micro practices, habits and routine of designers, a deeper understanding of social e-atmospherics possible functions in the future will be unpacked