354 research outputs found

    Genetic variation of Pyrenophora teres f. teres isolates in Western Australia and emergence of a Cyp51A fungicide resistance mutation

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    Plant Pathology published by John Wiley & Sons Ltd on behalf of British Society for Plant Pathology. Genome-wide, unlinked, simple sequence repeat markers were used to examine genetic variation and relationships within Pyrenophora teres f. teres, a common pathogen of barley, in Western Australia. Despite the region's geographic isolation, the isolates showed relatively high allelic variation compared to similar studies, averaging 7.11 alleles per locus. Principal component, Bayesian clustering and distance differentiation parameters provided evidence for both regional genotypic subdivision together with juxtaposing of isolates possessing different genetic backgrounds. Genotyping of fungicide resistant Cyp51A isolates indicated a single mutation event occurred followed by recombination and long-distance regional dispersal over hundreds of kilometres. Selection of recently emergent favourable alleles such as the Cyp51A mutation and a cultivar virulence may provide an explanation, at least in part, for juxtaposed genotypes. Factors affecting genotypic composition and the movement of new genotypes are discussed in the context of grower practices and pathogen epidemiology, together with the implications for resistance breeding

    A common deep source for upper-mantle upwellings below the Ibero-western Maghreb region from teleseismic P-wave travel-time tomography

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    Upper-mantle upwellings are often invoked as the cause of Cenozoic volcanism in the Ibero-western Maghreb region. However, their nature, geometry and origin are unclear. This study takes advantage of dense seismic networks, which cover an area extending from the Pyrenees in the north to the Canaries in the south, to provide a new high-resolution P-wave velocity model of the upper-mantle and topmost lower-mantle structure. Our images show three subvertical upper-mantle upwellings below the Canaries, the Atlas Ranges and the Gibraltar Arc, which appear to be rooted beneath the upper-mantle transition zone (MTZ). Two other mantle upwellings beneath the eastern Rif and eastern Betics surround the Gibraltar subduction zone. We propose a new geodynamic model in which narrow upper-mantle upwellings below the Canaries, the Atlas Ranges and the Gibraltar Arc rise from a laterally-propagating layer of material below the MTZ, which in turn is fed by a common deep source below the Canaries. In the Gibraltar region, the deeply rooted upwelling interacts with the Gibraltar slab. Quasi-toroidal flow driven by slab rollback induces the hot mantle material to flow around the slab, creating the two low-velocity anomalies below the eastern Betics and eastern Rif. Our results suggest that the Central Atlantic plume is a likely source of hot mantle material for upper-mantle upwellings in the Ibero-western Maghreb region

    Converting a series in \lambda to a series in \lambda^{-1}

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    We introduce a transformation for converting a series in a parameter, \lambda, to a series in the inverse of the parameter \lambda^{-1}. By applying the transform on simple examples, it becomes apparent that there exist relations between convergent and divergent series, and also between large- and small-coupling expansions. The method is also applied to the divergent series expansion of Euler-Heisenberg-Schwinger result for the one-loop effective action for constant background magnetic (or electric) field. The transform may help us gain some insight about the nature of both divergent (Borel or non-Borel summable series) and convergent series and their relationship, and how both could be used for analytical and numerical calculations.Comment: 7 pages, Latex, 3 figures; Typos corrected. To appear in Journal of Physics A: Math and Ge

    Adult Rat Bones Maintain Distinct Regionalized Expression of Markers Associated with Their Development

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    The incidence of limb bone fracture and subsequent morbidity and mortality due to excessive bone loss is increasing in the progressively ageing populations of both men and women. In contrast to bone loss in the weight-bearing limb, bone mass in the protective skull vault is maintained. One explanation for this could be anatomically diverse bone matrix characteristics generated by heterogeneous osteoblast populations. We have tested the hypothesis that adult bones demonstrate site-specific characteristics, and report differences at the organ, cell and transcriptome levels. Limb bones contain greater amounts of polysulphated glycosaminoglycan stained with Alcian Blue and have significantly higher osteocyte densities than skull bone. Site-specific patterns persist in cultured adult bone-derived cells both phenotypically (proliferation rate, response to estrogen and cell volumes), and at the level of specific gene expression (collagen triple helix repeat containing 1, reelin and ras-like and estrogen-regulated growth inhibitor). Based on genome-wide mRNA expression and cluster analysis, we demonstrate that bones and cultured adult bone-derived cells segregate according to site of derivation. We also find the differential expression of genes associated with embryological development (Skull: Zic, Dlx, Irx, Twist1 and Cart1; Limb: Hox, Shox2, and Tbx genes) in both adult bones and isolated adult bone-derived cells. Together, these site-specific differences support the view that, analogous to different muscle types (cardiac, smooth and skeletal), skull and limb bones represent separate classes of bone. We assign these differences, not to mode of primary ossification, but to the embryological cell lineage; the basis and implications of this division are discussed

    Comparative analysis of the lambda-interferons IL-28A and IL-29 regarding their transcriptome and their antiviral properties against hepatitis C virus.

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    Specific differences in signaling and antiviral properties between the different Lambda-interferons, a novel group of interferons composed of IL-28A, IL-28B and IL-29, are currently unknown. This is the first study comparatively investigating the transcriptome and the antiviral properties of the Lambda-interferons IL-28A and IL-29. Expression studies were performed by microarray analysis, quantitative PCR (qPCR), reporter gene assays and immunoluminometric assays. Signaling was analyzed by Western blot. HCV replication was measured in Huh-7 cells expressing subgenomic HCV replicon. All hepatic cell lines investigated as well as primary hepatocytes expressed both IFN-λ receptor subunits IL-10R2 and IFN-λR1. Both, IL-28A and IL-29 activated STAT1 signaling. As revealed by microarray analysis, similar genes were induced by both cytokines in Huh-7 cells (IL-28A: 117 genes; IL-29: 111 genes), many of them playing a role in antiviral immunity. However, only IL-28A was able to significantly down-regulate gene expression (n = 272 down-regulated genes). Both cytokines significantly decreased HCV replication in Huh-7 cells. In comparison to liver biopsies of patients with non-viral liver disease, liver biopsies of patients with HCV showed significantly increased mRNA expression of IL-28A and IL-29. Moreover, IL-28A serum protein levels were elevated in HCV patients. In a murine model of viral hepatitis, IL-28 expression was significantly increased. IL-28A and IL-29 are up-regulated in HCV patients and are similarly effective in inducing antiviral genes and inhibiting HCV replication. In contrast to IL-29, IL-28A is a potent gene repressor. Both IFN-λs may have therapeutic potential in the treatment of chronic HCV

    翻訳 動物倫理の西洋文化(3)アンドレーアス・C・ビマー 動物に居場所はない : 人間の公共の場から動物を追放する動きをめぐるエッセイ(1991) (特集 新津嗣郎教授、ジョン・ブランデル教授退職記念号)

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    AimAs the COVID-19 pandemic evolves, human milk banks world-wide continue to provide donor human milk to vulnerable infants who lack access to mother's own milk. Under these circumstances, ensuring the safety of donor human milk is paramount, as the risk of vertical transmission of SARS-CoV-2 is not fully understood. Here, we investigate the inactivation of SARS-CoV-2 in human milk by pasteurisation and the stability of SARS-CoV-2 in human milk under cold storage.MethodsSARS-CoV-2 was experimentally inoculated into human milk samples from healthy donors or into a control medium. Triplicates of each sample were layered onto uninfected cells after Holder pasteurisation (63°C for 30 min), heating to 56°C for 30 min, or after 48 h of storage at 4°C or -30°C. Infectious titres of virus were determined at 72 h post-infection by endpoint titration.ResultsFollowing heating to 63°C or 56°C for 30 min, replication competent (i.e. live) SARS-CoV-2 was undetected in both human milk and the control medium. Cold storage of SARS-CoV-2 in human milk (either at 4°C or -30°C) did not significantly impact infectious viral load over a 48 h period.ConclusionSARS-CoV-2 is effectively inactivated by Holder pasteurisation, suggesting that existing milk bank processes will effectively mitigate the risk of transmission of SARS-COV-2 to vulnerable infants through pasteurised donor human milk. The demonstrated stability of SARS-CoV-2 in refrigerated or frozen human milk may assist in the development of guidelines around safe expressing and storing of milk from COVID-19 infected mothers

    SARS Coronavirus-2 Microneutralisation and Commercial Serological Assays Correlated Closely for Some but Not All Enzyme Immunoassays

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    Serological testing for SARS-CoV-2-specific antibodies provides important research and diagnostic information relating to COVID-19 prevalence, incidence and host immune response. A greater understanding of the relationship between functionally neutralising antibodies detected using microneutralisation assays and binding antibodies detected using scalable enzyme immunoassays (EIA) is needed in order to address protective immunity post-infection or vaccination, and assess EIA suitability as a surrogate test for screening of convalescent plasma donors. We assessed whether neutralising antibody titres correlated with signal cut-off ratios in five commercially available EIAs, and one in-house assay based on expressed spike protein targets. Sera from recovered patients or convalescent plasma donors who reported laboratory-confirmed SARS-CoV-2 infection (n = 200), and negative control sera collected prior to the COVID-19 pandemic (n = 100), were assessed in parallel. Performance was assessed by calculating EIA sensitivity and specificity with reference to microneutralisation. Neutralising antibodies were detected in 166 (83%) samples. Compared with this, the most sensitive EIAs were the Cobas Elecsys Anti-SARS-CoV-2 (98%) and Vitros Immunodiagnostic Anti-SARS-CoV-2 (100%), which detect total antibody targeting the N and S1 antigens, respectively. The assay with the best quantitative relationship with microneutralisation was the Euroimmun IgG. These results suggest the marker used (total Ab vs. IgG vs. IgA) and the target antigen are important determinants of assay performance. The strong correlation between microneutralisation and some commercially available assays demonstrates their potential for clinical and research use in assessing protection following infection or vaccination, and use as a surrogate test to assess donor suitability for convalescent plasma donation

    Temperature dependence of the anomalous effective action of fermions in two and four dimensions

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    The temperature dependence of the anomalous sector of the effective action of fermions coupled to external gauge and pseudo-scalar fields is computed at leading order in an expansion in the number of Lorentz indices in two and four dimensions. The calculation preserves chiral symmetry and confirms that a temperature dependence is compatible with axial anomaly saturation. The result checks soft-pions theorems at zero temperature as well as recent results in the literature for the pionic decay amplitude into static photons in the chirally symmetric phase. The case of chiral fermions is also considered.Comment: RevTex, 19 pages, no figures. References adde

    SARS-CoV-2 neutralizing antibodies: Longevity, breadth, and evasion by emerging viral variants.

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    The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) antibody neutralization response and its evasion by emerging viral variants and variant of concern (VOC) are unknown, but critical to understand reinfection risk and breakthrough infection following vaccination. Antibody immunoreactivity against SARS-CoV-2 antigens and Spike variants, inhibition of Spike-driven virus-cell fusion, and infectious SARS-CoV-2 neutralization were characterized in 807 serial samples from 233 reverse transcription polymerase chain reaction (RT-PCR)-confirmed Coronavirus Disease 2019 (COVID-19) individuals with detailed demographics and followed up to 7 months. A broad and sustained polyantigenic immunoreactivity against SARS-CoV-2 Spike, Membrane, and Nucleocapsid proteins, along with high viral neutralization, was associated with COVID-19 severity. A subgroup of "high responders" maintained high neutralizing responses over time, representing ideal convalescent plasma donors. Antibodies generated against SARS-CoV-2 during the first COVID-19 wave had reduced immunoreactivity and neutralization potency to emerging Spike variants and VOC. Accurate monitoring of SARS-CoV-2 antibody responses would be essential for selection of optimal responders and vaccine monitoring and design
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