42 research outputs found

    Spatially Resolved Chemistry in Nearby Galaxies I. The Center of IC 342

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    We have imaged emission from the millimeter lines of eight molecules--C2H, C34S, N2H+, CH3OH, HNCO, HNC, HC3N, and SO--in the central half kpc of the nearby spiral galaxy IC 342. The 5" (~50 pc) resolution images were made with OVRO. Using these maps we obtain a picture of the chemistry within the nuclear region on the sizescales of individual GMCs. Bright emission is detected from all but SO. There are marked differences in morphology for the different molecules. A principal component analysis is performed to quantify similarities and differences among the images. This analysis reveals that while all molecules are to zeroth order correlated, that is, they are all found in dense molecular clouds, there are three distinct groups of molecules distinguished by the location of their emission within the nuclear region. N2H+, C18O, HNC and HCN are widespread and bright, good overall tracers of dense molecular gas. C2H and C34S, tracers of PDR chemistry, originate exclusively from the central 50-100 pc region, where radiation fields are high. The third group of molecules, CH3OH and HNCO, correlates well with the expected locations of bar-induced orbital shocks. The good correlation of HNCO with the established shock tracer molecule CH3OH is evidence that this molecule, whose chemistry has been uncertain, is indeed produced by processing of grains. HC3N is observed to correlate tightly with 3mm continuum emission, demonstrating that the young starbursts are the sites of the warmest and densest molecular gas. We compare our HNC images with the HCN images of Downes et al. (1992) to produce the first high resolution, extragalactic HCN/HNC map: the HNC/HCN ratio is near unity across the nucleus and the correlation of both of these gas tracers with the star formation is excellent. (Abridged).Comment: 54 pages including 10 figures and 8 tables. Accepted for publication in Ap

    Leveraging knowledge as a competitive asset? The intensity, performance and structure of universities’ entrepreneurial knowledge exchange activities at a regional level

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    © 2016, The Author(s). Universities are no longer considered to be isolated islands of knowledge, but as institutions increasingly engaged with a range of external partners through entrepreneurial activities. This paper examines the associations between the intensity and performance of knowledge exchange activities undertaken in UK universities with non-academic actors. Drawing on data concerning the structural factors of interactions of universities in the UK with external partners, the paper sheds further light on the nature of these activities through a prism of competitive and uncompetitive regions in order to better understand how universities may be able to leverage both their knowledge and partnerships more effectively as competitive assets. On the one hand, it is found that academics in uncompetitive regions are more intensively engaged in entrepreneurial activities but generate less income from them than their counterparts in competitive regions, suggesting that there are differences in the income-generating capacity of academics across regions. On the other hand, academic knowledge is found to be more strongly bounded within a certain distance in uncompetitive regions whilst geographical distance seems less of a hindrance to academics in competitive regions

    The Beta-adrenergic agonist, Ractopamine, increases skeletal muscle expression of Asparagine Synthetase as part of an integrated stress response gene program

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    Abstract Synthetic beta-adrenergic agonists (BA) have broad biomedical and agricultural application for increasing lean body mass, yet a poor understanding of the biology underpinning these agents is limiting further drug discovery potential. Growing female pigs (77 ± 7 kg) were administered the BA, Ractopamine (20 ppm in feed), or the recombinant growth hormone (GH), Reporcin (10 mg/48 hrs injected) for 1, 3, 7, 13 (n = 10 per treatment, per time point) or 27 days (n = 15 per treatment). Using RNA-sequencing and inferred pathway analysis, we examined temporal changes to the Longissimus Dorsi skeletal muscle transcriptome (n = 3 per treatment, per time point) relative to a feed-only control cohort. Gene expression changes were affirmed by quantitative-PCR on all samples (n = 164). RNA-sequencing analysis revealed that BA treatment had greater effects than GH, and that asparagine synthetase (Asns) was the 5th most significantly increased gene by BA at day 3. ASNS protein expression was dramatically increased by BA treatment at day 7 (p < 0.05). The most significantly increased gene at day 3 was activating transcription factor 5 (Atf5), a transcription factor known to regulate ASNS gene expression. Gene and protein expression of Atf4, another known regulator of Asns expression, was not changed by BA treatment. Expression of more than 20 known Atf4 target genes were increased by BA treatment, suggesting that BA treatment induces an integrated stress response (ISR) in skeletal muscle of pigs. In support of this, mRNA expression of sestrin-2 (Sesn2) and cyclin-dependant kinase 1 alpha (Cdkn1a), two key stress-responsive genes and negative regulators of cellular growth, were also strongly increased from day 3 of BA treatment. Finally, tRNA charging was the most significantly enriched pathway induced by BA treatment, suggesting alterations to the translational capacity/efficiency of the muscle. BA-mediated changes to the skeletal muscle transcriptome are highly indicative of an integrated stress response (ISR), particularly genes relating to amino acid biosynthesis and protein translational capacity

    A novel copro-diagnostic molecular method for qualitative detection and identification of parasitic nematodes in amphibians and reptiles

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    © 2017 Huggins et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Anthropogenic disturbance via resource acquisition, habitat fragmentation and climate change, amongst other factors, has led to catastrophic global biodiversity losses and species extinctions at an accelerating rate. Amphibians are currently one of the worst affected classes with at least a third of species categorised as being threatened with extinction. At the same time, they are also critically important for many habitats and provide man with a powerful proxy for ecosystem health by acting as a bioindicator group. Whilst the causes of synchronised amphibian losses are varied recent research has begun to highlight a growing role that macroparasites are playing in amphibian declines. However, diagnosing parasite infection in the field can be problematic, principally relying on collection and euthanasia of hosts, followed by necropsy and morphological identification of parasites in situ. The current study developed a non-invasive PCR-based methodology for sensitive detection and identification of parasitic nematode DNA released in the faeces of infected amphibians as egg or tissue fragments (environmental DNA). A DNA extraction protocol optimised for liberation of DNA from resilient parasite eggs was developed alongside the design of a novel, nematode universal, degenerate primer pair, thus avoiding the difficulties of using species specific primers in situations where common parasite species are unknown. Used in conjunction this protocol and primer pair was tested on a wide range of faecal samples from captive and wild amphibians. The primers and protocol were validated and detected infections, including a Railletnema nematode infection in poison dart frogs from ZSL London Zoo and Mantella cowani frogs in the wild. Furthermore, we demonstrate the efficacy of our PCR-based protocol for detecting nematode infection in other hosts, such as the presence of pinworm (Aspiculuris) in two tortoise species and whipworm (Trichuris muris) in mice. Our environmental DNA approach mitigates problems associated with microscopic identification and can be applied to detect nematode parasitoses in wild and captive hosts for infection surveillance and maintenance of healthy populations

    Correction to: Cluster identification, selection, and description in Cluster randomized crossover trials: the PREP-IT trials

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    An amendment to this paper has been published and can be accessed via the original article

    Patient and stakeholder engagement learnings: PREP-IT as a case study

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    Dogs are reservoir hosts of the zoonotic Dirofilaria sp. ‘hongkongensis’ and potentially of Brugia sp. Sri Lanka genotype in Sri Lanka

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    In 2016, the World Health Organization declared Sri Lanka as having successfully eliminated lymphatic filariasis as a public health concern. However, in recent decades, several infections with subperiodic filarial species suggestive of zoonotic infections have been recorded across the country. The arthropod-borne filarioids Dirofilaria repens, Brugia malayi, Brugia ceylonensis, and Acanthocheilonema reconditum are historically known to be endemic in dogs in Sri Lanka. Despite this, limited information on the prevalence, diversity, and predictors of filarial infections in dogs in the country has resulted in suboptimal control and prevention of these parasites, some of which are known to be zoonotic. To address this, whole blood and metadata were collected and analysed from 423 pet dogs across three geo-climatic zones within Sri Lanka. Blood samples were screened using the Modified Knott's Test (MKT) and PCR followed by Sanger sequencing. Multivariable logistic regression models were used to assess predictors for canine filarial infections. Dirofilaria sp. ‘hongkongensis’ (Dirofilaria sp. HK) and Brugia sp. Sri Lanka (SL) genotype were identified infecting dogs. The overall prevalence of filarial infection in pet dogs by PCR was 36.9% (95% CI 32.3–41.7%, n = 156), compared to 18.8% (95% CI 15.2–22.9%, n = 79) detected using the MKT. >80% of filarial-positive dogs were infected by Dirofilaria sp. HK, while the remaining dogs were infected by Brugia sp. SL genotype. Increasing age (p < 0.001) and residing in the low-country wet zone (p < 0.001), which includes regions that were endemic for human filariasis in Sri Lanka, were associated with filarial infections in dogs. No clear pathognomonic signs for filarial infection were identified, indicating that dogs act as reservoirs for these potentially zoonotic pathogens. Given the morphological similarity of Dirofilaria HK and Brugia sp. SL microfilariae with those of D. repens and B. malayi, respectively, it is likely that these species have been misidentified in the past. Prevention and control measures of these potentially zoonotic canine filarial infections are highly advocated to safeguard both canine and human health

    Transmission of haemotropic mycoplasma in the absence of arthropod vectors within a closed population of dogs on ectoparasiticides

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    Abstract Dog-infecting haemotropic mycoplasmas (haemoplasmas), such as Mycoplasma haemocanis and Candidatus Mycoplasma haematoparvum are common blood-borne pathogens of canines that can potentially inflict a substantial burden of disease, particularly in immunosuppressed individuals. Nonetheless, the transmission of these pathogens remains debated as more evidence emerges that they may not be transmitted by vectors, but instead use alternative methods such as aggressive interactions and vertical transmission. Here, we treated forty dogs with two different topically-acting ectoparasiticide products able to prevent vector-borne pathogen infections during an 8-month community trial in Cambodia. A total absence of ectoparasites were observed at all time points, and no new infections caused by pathogens confirmed as being vectorially-transmitted were detected, i.e., Babesia vogeli, Ehrlichia canis, Anaplasma platys, and Hepatozoon canis. Conversely, the number of haemoplasma infections in dogs on both ectoparasiticides rose significantly, with an incidence of 26 infections per 100 dogs at risk per year, providing strong evidence of non-vectorial transmission. Over the study period, dog aggression and fighting were frequently observed, highlighting a different potential mode of transmission. This study presents the first robust evidence that canine haemoplasmas may be transmitted without arthropod vectors drawing attention to the need for new methods to prevent their transmission

    Next-generation sequencing metabarcoding assays reveal diverse bacterial vector-borne pathogens of Mongolian dogs

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    Bacterial vector-borne pathogens (BVBPs) negatively impact canine health worldwide, with several also being zoonotic, posing an additional disease risk to humans. To date, BVBPs have been reported in humans and various sylvatic and domestic animal hosts across multiple Mongolian aimags (provinces); however, there has been no published data on these pathogens within Mongolia’s canine populations. Collection of such data is important given Mongolia’s size, diverse number of climatic regions, and large population of dogs, most of which closely share their environment with humans and livestock. Therefore, a bacteria-targeting next-generation sequencing metabarcoding (mNGS) assay was used to test the feasibility of mNGS as a proof-of-concept study to ascertain the detection of BVBP in 100 Mongolian dogs. The majority of dogs (n = 74) were infected with at least one of six BVBPs identified; including three species of haemoplasmas (also known as haemotropic mycoplasmas, n = 71), Bartonella rochalimae (n = 3), Ehrlichia spp. (n = 2) and Anaplasma platys (n = 1). Univariable analysis found sex, housing, and role of the dog to be associated with BVBP infection. Male dogs had 4.33 (95% CI: 1.61–11.62, P = 0.003) times the odds of infection with BVBPs compared to females. The majority of dogs included in this study were kept outdoors and had regular direct contact with both livestock and humans, indicating that dogs may contribute to the transmission and dissemination of BVBPs in Mongolia and could act as epidemiological sentinels. This study underscores the importance of pathogen surveillance studies in under-researched regions, reinforces the efficacy of mNGS as an explorative diagnostic tool, and emphasises the need for further larger-scale seroprevalence studies of Mongolian dogs
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