187 research outputs found
A review of African horse sickness and its implications for Ireland
African horse sickness is an economically highly important non-contagious but infectious Orbivirus disease that is transmitted by various species of Culicoides midges. The equids most severely affected by the virus are horses, ponies, and European donkeys; mules are somewhat less susceptible, and African donkeys and zebra are refractory to the devastating consequences of infection. In recent years, Bluetongue virus, an Orbivirus similar to African horse sickness, which also utilises Culicoides spp. as its vector, has drastically increased its range into previously unaffected regions in northern Europe, utilising indigenous vector species, and causing widespread economic damage to the agricultural sector. Considering these events, the current review outlines the history of African horse sickness, including information concerning virus structure, transmission, viraemia, overwintering ability, and the potential implications that an outbreak would have for Ireland. While the current risk for the introduction of African horse sickness to Ireland is considered at worst ‘very low’, it is important to note that prior to the 2006 outbreak of Bluetongue in northern Europe, both diseases were considered to be of equal risk to the United Kingdom (‘medium-risk’). It is therefore likely that any outbreak of this disease would have serious socio-economic consequences for Ireland due to the high density of vulnerable equids and the prevalence of Culicoides species, potentially capable of vectoring the virus
Mechanism Underlying Defective Interferon Gamma-Induced IDO Expression in Non-obese Diabetic Mouse Fibroblasts
Indoleamine 2,3-dioxygenase (IDO) can locally suppress T cell-mediated immune responses. It has been shown that defective self-tolerance in early prediabetic female non-obese diabetic (NOD) mice can be attributed to the impaired interferon-gamma (IFN-γ)- induced IDO expression in dendritic cells of these animals. As IFN-γ can induce IDO in both dendritic cells and fibroblasts, we asked the question of whether there exists a similar defect in IFN-γ-induced IDO expression in NOD mice dermal fibroblasts. To this end, we examined the effect of IFN-γ on expression of IDO and its enzymatic activity in NOD dermal fibroblasts. The results showed that fibroblasts from either prediabetic (8 wks of age) female or male, and diabetic female or male (12 and 24 wks of age respectively) NOD mice failed to express IDO in response to IFN-γ treatment. To find underlying mechanisms, we scrutinized the IFN- γ signaling pathway and investigated expression of other IFN-γ-modulated factors including major histocompatibility complex class I (MHC-I) and type I collagen (COL-I). The findings revealed a defect of signal transducer and activator of transcription 1 (STAT1) phosphorylation in NOD cells relative to that of controls. Furthermore, we found an increase in MHC-I and suppression of COL-I expression in fibroblasts from both NOD and control mice following IFN-γ treatment; indicating that the impaired response to IFN-γ in NOD fibroblasts is specific to IDO gene. Finally, we showed that an IFN-γ-independent IDO expression pathway i.e. lipopolysaccharide (LPS)-mediated-c-Jun kinase is operative in NOD mice fibroblast. In conclusion, the findings of this study for the first time indicate that IFN-γ fails to induce IDO expression in NOD dermal fibroblasts; this may partially be due to defective STAT1 phosphorylation in IFN-γ-induced-IDO signaling pathway
Drinking behaviour and alcohol-related harm amongst older adults: analysis of existing UK datasets.
Older adults experience age-related physiological changes that increase sensitivity and decrease tolerance to alcohol and there are a number of age-related harms such as falls, social isolation and elder abuse, which are compounded by alcohol misuse. Despite this unique vulnerability and the fact that the number of older adults is increasing, the literature on drinking behaviour and alcohol-related harm in older adults is sparse. This article describes a secondary analysis of UK data to address this knowledge gap
Recommended from our members
Heat and moisture budgets from airborne measurements and high-resolution model simulations
High-resolution simulations with a mesoscale model are performed to estimate heat and moisture budgets of a well-mixed boundary layer. The model budgets are validated against energy budgets obtained from airborne measurements over heterogeneous terrain in Western Germany. Time rate of change, vertical divergence, and horizontal advection for an atmospheric column of air are estimated. Results show that the time trend of specific humidity exhibits some deficiencies, while the potential temperature trend is matched accurately. Furthermore, the simulated turbulent surface fluxes of sensible and latent heat are comparable to the measured fluxes, leading to similar values of the vertical divergence. The analysis of different horizontal model resolutions exhibits improved surface fluxes with increased resolution, a fact attributed to a reduced aggregation effect. Scale-interaction effects could be identified: while time trends and advection are strongly influenced by mesoscale forcing, the turbulent surface fluxes are mainly controlled by microscale processes
Natural CD4+ T-Cell Responses against Indoleamine 2,3-Dioxygenase
The enzyme indoleamine 2,3-dioxygenase (IDO) contributes to immune tolerance in a variety of settings. In cancer IDO is expressed within the tumor itself as well as in antigen-presenting cells in tumor-draining lymph nodes, where it endorses the establishment of peripheral immune tolerance to tumor antigens. Recently, we described cytotoxic CD8(+) T-cell reactivity towards IDO-derived peptides.In the present study, we show that CD4(+) helper T cells additionally spontaneously recognize IDO. Hence, we scrutinized the vicinity of the previously described HLA-A*0201-restricted IDO-epitope for CD4(+) T-cell epitopes. We demonstrated the presence of naturally occurring IDO-specific CD4(+) T cells in cancer patients and to a lesser extent in healthy donors by cytokine release ELISPOT. IDO-reactive CD4(+) T cells released IFN-γ, TNF-α, as well as IL-17. We confirm HLA class II-restriction by the addition of HLA class II specific blocking antibodies. In addition, we detected a trend between class I- and class II-restricted IDO responses and detected an association between IDO-specific CD4(+) T cells and CD8(+) CMV-responses. Finally, we could detect IL-10 releasing IDO-reactive CD4(+) T cells.IDO is spontaneously recognized by HLA class II-restricted, CD4(+) T cells in cancer patients and in healthy individuals. IDO-specific T cells may participate in immune-regulatory networks where the activation of pro-inflammatory IDO-specific CD4(+) responses may well overcome or delay the immune suppressive actions of the IDO-protein, which are otherwise a consequence of the early expression of IDO in maturing antigen presenting cells. In contrast, IDO-specific regulatory T cells may enhance IDO-mediated immune suppression
Patient-derived mutations within the N-terminal domains of p85α impact PTEN or Rab5 binding and regulation
The p85α protein regulates flux through the PI3K/PTEN signaling pathway, and also controls receptor trafficking via regulation of Rab-family GTPases. In this report, we determined the impact of several cancer patient-derived p85α mutations located within the N-terminal domains of p85α previously shown to bind PTEN and Rab5, and regulate their respective functions. One p85α mutation, L30F, significantly reduced the steady state binding to PTEN, yet enhanced the stimulation of PTEN lipid phosphatase activity. Three other p85α mutations (E137K, K288Q, E297K) also altered the regulation of PTEN catalytic activity. In contrast, many p85α mutations reduced the binding to Rab5 (L30F, I69L, I82F, I177N, E217K), and several impacted the GAP activity of p85α towards Rab5 (E137K, I177N, E217K, E297K). We determined the crystal structure of several of these p85α BH domain mutants (E137K, E217K, R262T E297K) for bovine p85α BH and found that the mutations did not alter the overall domain structure. Thus, several p85α mutations found in human cancers may deregulate PTEN and/or Rab5 regulated pathways to contribute to oncogenesis. We also engineered several experimental mutations within the p85α BH domain and identified L191 and V263 as important for both binding and regulation of Rab5 activit
Combining dispersion modelling with synoptic patterns to understand the wind-borne transport into the UK of the bluetongue disease vector
Bluetongue, an economically important animal disease, can be spread over long distances by carriage of insect vectors (Culicoides biting midges) on the wind. The weather conditions which influence the midge’s flight are controlled by synoptic scale atmospheric circulations. A method is proposed that links wind-borne dispersion of the insects to synoptic circulation through the use of a dispersion model in combination with principal component analysis (PCA) and cluster analysis. We illustrate how to identify the main synoptic situations present during times of midge incursions into the UK from the European continent. A PCA was conducted on high-pass-filtered mean sea-level pressure data for a domain centred over north-west Europe from 2005 to 2007. A clustering algorithm applied to the PCA scores indicated the data should be divided into five classes for which averages were calculated, providing a classification of the main synoptic types present. Midge incursion events were found to mainly occur in two synoptic categories; 64.8% were associated with a pattern displaying a pressure gradient over the North Atlantic leading to moderate south-westerly flow over the UK and 17.9% of the events occurred when high pressure dominated the region leading to south-easterly or easterly winds. The winds indicated by the pressure maps generally compared well against observations from a surface station and analysis charts. This technique could be used to assess frequency and timings of incursions of virus into new areas on seasonal and decadal timescales, currently not possible with other dispersion or biological modelling methods
The PI3K regulatory subunits p55α and p50α regulate cell death in vivo.
The phosphatidylinositol 3-kinase (PI3K) regulatory subunits p55α and p50α are coordinately transcriptionally upregulated by signal transducer and activator of transcription 3 (Stat3) at the onset of mammary gland involution, a process that requires Stat3. Deletion of both p55α and p50α subunits in vivo abrogated mammary epithelial cell death during involution. This was associated also with reduced cytosolic levels and activity of the cysteine protease cathepsin L, which is implicated in lysosomal-mediated programmed cell death (LM-PCD) and is upregulated in involution. Furthermore, involution is delayed in cathepsin L-deficient mice suggesting that the p55α/p50α subunits mediate cell death in part by elevating the level of cathepsin L resulting in increased cytosolic activity. Surprisingly, we found that p55α/p50α localize to the nucleus where they bind to chromatin and regulate transcription of a subset of inflammatory/acute phase genes that are also Stat3 targets. Our findings reveal a novel role for these PI3K regulatory subunits as regulators of LM-PCD in vivo.We thank Maximilian Blanck and Ivan Ferrer-Vicens for immunofluorescence studies, Helen Skelton for tissue histology and the Watson lab members for helpful discussions. This work was funded by BBSRC and MRC grants (BB/D012937/1 and MR/J001023/1) awarded to CJW, SP is the recipient of a Marie Curie IEF fellowship (EU Marie Curie grant no. 273365), KN was supported by a BBSRC CASE PhD studentship, HR is funded by a Cambridge Cancer Center PhD studentship and PAK is the recipient of a Trinity College fellowship. TR was supported by the Excellence Initiative of the German Federal and State Governments (EXC 294), and the Deutche Forschungsgemeinschaft SFB 850 project B7.This is the accepted manuscript version of the paper. The final version is available online from Nature Publishing Group at http://www.nature.com/cdd/journal/vaop/ncurrent/full/cdd201459a.html
A Key Role of Dendritic Cells in Probiotic Functionality
BACKGROUND: Disruption of the intestinal homeostasis and tolerance towards the resident microbiota is a major mechanism involved in the development of inflammatory bowel disease. While some bacteria are inducers of disease, others, known as probiotics, are able to reduce inflammation. Because dendritic cells (DCs) play a central role in regulating immune responses and in inducing tolerance, we investigated their role in the anti-inflammatory potential of probiotic lactic acid bacteria. METHODOLOGY/PRINCIPAL FINDINGS: Selected LAB strains, while efficiently taken up by DCs in vitro, induced a partial maturation of the cells. Transfer of probiotic-treated DCs conferred protection against 2, 4, 6-trinitrobenzenesulfonic acid (TNBS)-induced colitis. Protection was associated with a reduction of inflammatory scores and colonic expression of pro-inflammatory genes, while a high local expression of the immunoregulatory enzyme indolamine 2, 3 dioxgenase (IDO) was observed. The preventive effect of probiotic-pulsed DCs required not only MyD88-, TLR2- and NOD2-dependent signaling but also the induction of CD4+ CD25+ regulatory cells in an IL-10-independent pathway. CONCLUSIONS/SIGNIFICANCE: Altogether, these results suggest that selected probiotics can stimulate DC regulatory functions by targeting specific pattern-recognition receptors and pathways. The results not only emphasize the role of DCs in probiotic immune interactions, but indicate a possible role in immune-intervention therapy for IBD
Liver X receptor agonist treatment attenuates cardiac dysfunction in type 2 diabetic db/db mice
- …