1,311 research outputs found
Complete genome sequence of Salmonella enterica serovar Typhimurium U288
Salmonella enterica serovar Typhimurium U288 has firmly established itself within the United Kingdom pig production industry. The prevalence of this highly pathogenic multidrug-resistant serovar at such a critical point in the food chain is therefore of great concern. To enhance our understanding of this microorganism, whole-genome and plasmid sequencing was performed
Salmonella Typhimurium-specific bacteriophage ΦSH19 and the origins of species specificity in the Vi01-like phage family
<p>Abstract</p> <p>Background</p> <p>Whole genome sequencing of bacteriophages suitable for biocontrol of pathogens in food products is a pre-requisite to any phage-based intervention procedure. Trials involving the biosanitization of <it>Salmonella </it>Typhimurium in the pig production environment identified one such candidate, ΦSH19.</p> <p>Results</p> <p>This phage was sequenced and analysis of its 157,785 bp circular dsDNA genome revealed a number of interesting features. ΦSH19 constitutes another member of the recently-proposed <it>Myoviridae </it>Vi01-like family of phages, containing <it>S</it>. Typhi-specific Vi01 and <it>Shigella</it>-specific SboM-AG3. At the nucleotide level ΦSH19 is highly similar to phage Vi01 (80-98% pairwise identity over the length of the genome), with the major differences lying in the region associated with host-range determination. Analyses of the proteins encoded within this region by ΦSH19 revealed a cluster of three putative tail spikes. Of the three tail spikes, two have protein domains associated with the pectate lyase family of proteins (Tsp2) and P22 tail spike family (Tsp3) with the prospect that these enable <it>Salmonella </it>O antigen degradation. Tail spike proteins of Vi01 and SboM-AG3 are predicted to contain conserved right-handed parallel β-helical structures but the internal protein domains are varied allowing different host specificities.</p> <p>Conclusions</p> <p>The addition or exchange of tail spike protein modules is a major contributor to host range determination in the Vi01-like phage family.</p
Cytochrome P4501A is Induced in Endothelial Cell Lines From the Kidney and Lung of the Bottlenose Dolphin, \u3ci\u3eTursiops truncatus\u3c/i\u3e
Marine mammals respond to the presence of polycyclic and planar halogenated aromatic hydrocarbons (PAH or PHAH) with the induced expression in endothelium of cytochrome P4501A1, regulated through the aryl hydrocarbon receptor (AHR) transcription factor. Physiological responses in other animals, such as edema and inflammation indicate that the endothelium may be compromised by exposure to AHR agonists, which are ubiquitous in the marine environment. In other mammals and fish the cellular and molecular consequences of exposure to AHR agonists have been elucidated in cultured endothelial cells. We have cultured and characterized cetacean endothelial cells (EC) and used them in induction studies. Endothelial cells were cultured from the lung and kidney of the bottlenose dolphin, Tursiops truncates, and exposed to the AHR agonists β-naphthoflavone (βNF) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). βNF (1–3 μM) induced significant increases in CYP1A1 (O-deethylation of 7-ethoxyresorufin to resorufin; EROD) activity to 3.6 and 0.92 pmol/mg/min in lung and kidney EC, respectively. TCDD was more potent than βNF, and more efficacious, with maximum induction of CYP1A1 activity of 10.1 and 15.2 pmol/mg/min in lung and kidney EC at 3–10 nM TCDD. The differential response indicates that the lung and kidney endothelial cells in culture retain the ability to respond in a selective manner to specific stimuli. Both the molecular mechanisms of induction and the physiological consequences, especially in the vasculature, of toxicant exposure can be studied in this system
Cytochrome P4501A is induced in endothelial cell lines from the kidney and lung of the bottlenose dolphin, Tursiops truncatus
Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Aquatic Toxicology 76 (2006): 295-305, doi:10.1016/j.aquatox.2005.10.005.Marine mammals respond to the presence of polycyclic and planar
halogenated aromatic hydrocarbons (PAH or PHAH) with the induced expression
in endothelium of cytochrome P4501A1, regulated through the aryl hydrocarbon
receptor (AHR) transcription factor. Physiological responses in other animals,
such as edema and inflammation indicate that the endothelium may be
compromised by exposure to AHR agonists, which are ubiquitous in the marine
environment. In other mammals and fish the cellular and molecular
consequences of exposure to AHR agonists have been elucidated in cultured
endothelial cells. We have cultured and characterized cetacean endothelial cells
(EC) and used them in induction studies. Endothelial cells were cultured from the
lung and kidney of the bottlenose dolphin Tursiops truncatus and exposed to the
AHR agonists β-naphthoflavone (βNF) and 2,3,7,8-tetrachlorodibenzo-p-dioxin
(TCDD). βNF (1-3 μM) induced significant increases in CYP1A1(O-deethylation
of 7-ethoxyresorufin to resorufin;EROD) activity to 3.6 and 0.92 pmol/mg/min in
lung and kidney EC, respectively. TCDD was more potent than βNF, and more
efficacious, with maximum induction of CYP1A1activity of 10.1 and 15.2
pmol/mg/min in lung and kidney EC at 3-10 nM TCDD. The differential response
indicates that the lung and kidney endothelial cells in culture retain the ability to
respond in a selective manner to specific stimuli. Both the molecular mechanisms
of induction and the physiological consequences, especially in the vasculature, of
toxicant exposure can be studied in this system.Part of this work was completed during a faculty fellowship from Fordham
University for RAG. The Faculty Research Council of Fordham University
provided partial support for RAG. This research was supported by NIH grant 5-
P42-ES07381 and by U.S.EPA grant R827102-01-0. This research is an
outgrowth and continuing impact of Sea Grant Number Grant No. NA90-
AA-D-SG480, project NA86RG0075-R/P61
The complete plasmid sequences of Salmonella enterica serovar Typhimurium U288.
Salmonella enterica Serovar Typhimurium U288 is an emerging pathogen of pigs. The strain contains three plasmids of diverse origin that encode traits that are of concern for food security and safety, these include antibiotic resistant determinants, an array of functions that can modify cell physiology and permit genetic mobility. At 148,711 bp, pSTU288-1 appears to be a hybrid plasmid containing a conglomerate of genes found in pSLT of S. Typhimurium LT2, coupled with a mosaic of horizontally-acquired elements. Class I integron containing gene cassettes conferring resistance against clinically important antibiotics and compounds are present in pSTU288-1. A curious feature of the plasmid involves the deletion of two genes encoded in the Salmonella plasmid virulence operon (spvR and spvA) following the insertion of a tnpA IS26-like element coupled to a blaTEM gene. The spv operon is considered to be a major plasmid-encoded Salmonella virulence factor that is essential for the intracellular lifecycle. The loss of the positive regulator SpvR may impact on the pathogenesis of S. Typhimurium U288. A second 11,067 bp plasmid designated pSTU288-2 contains further antibiotic resistance determinants, as well as replication and mobilization genes. Finally, a small 4675 bp plasmid pSTU288-3 was identified containing mobilization genes and a pleD-like G-G-D/E-E-F conserved domain protein that modulate intracellular levels of cyclic di-GMP, and are associated with motile to sessile transitions in growth
Indigenous Wāhine Talking Critically in the Museum Space
As greater numbers of community groups experience social disconnect, museums need to find better methods of engagement in order to remain relevant. We know that museums are no longer neutral spaces; in fact, they have a role to play in activism, which means they can shift their mission to support local communities celebrate and protect their Indigenous heritage (Drubay and Singhal 2020; Message 2018; Shelton 2013). What follows is a meditation by researchers in Aotearoa New Zealand who engage with Pacific-Indigenous concepts and museum practice in unique ways. Our big idea is to see “Oceania through Indigenous eyes” (Lagi-Maama 2019: 291) and, in particular, the eyes of Nālani Wilson-Hokowhitu with mo‘okū‘auhau to Kalapana, Hawai‘i, and Moloka‘i Nui a Hina; Maree Mills with whakapapa to Tongariro, Taupō, and Ngāti Tūwharetoa; and Rachel Yates, who hails from Vaisala, Sāmoa. As a collective, their curatorial talano kaōrero/mo‘olelo/stories connect to current debates in the museum world where local problems need local solutions. In this instance, Wilson-Hokowhitu and Mills share the ideas that shaped their mahi at Waikato Museum Te Whare Taonga o Waikato in Hamilton, and Yates has just finished a COVID-19 project as Curator of Pacific Cultures at the Museum of New Zealand Te Papa Tongarewa in Wellington.</jats:p
Synthetic Spectral Analysis of the Hot Component in the S-Type Symbiotic Variable EG Andromeda
We have applied grids of NLTE high gravity model atmospheres and optically
thick accretion disk models for the first time to archival IUE and FUSE spectra
of the S-type symbiotic variable EG And taken at superior spectroscopic
conjunction when Rayleigh scattering should be minimal and the hot component is
viewed in front of the red giant. For EG And's widely accepted, published hot
component mass, orbital inclination and distance from the Hipparcos parallax,
we find that hot, high gravity, NLTE photosphere model fits to the IUE spectra
yield distances from the best-fitting models which agree with the Hipparcos
parallax distance but at temperatures substantially lower than the modified
Zanstra temperatures. NLTE fits to an archival FUSE spectrum taken at the same
orbital phase as the IUE spectra yield the same temperature as the IUE
temperature (50,000K). However, for the same hot component mass, inclination
and parallax-derived distance, accretion disk models at moderately high
inclinations, with accretion rates to 1\times 10^{-9} M_{\sun}/yr for white dwarf masses M_{wd} = 0.4
M_{\sun} yield distances grossly smaller than the distance from the Hipparcos
parallax. Therefore, we rule out an accretion disk as the dominant source of
the FUV flux. Our findings support a hot bare white dwarf as the dominant
source of FUV flux.Comment: AJ, Oct. 200
Systemic Effects of Arctic Pollutants in Beluga Whales Indicated by CYP1A1 Expression
Cytochrome P450 1A1 (CYP1A1) is induced by exposure to polycyclic aromatic hydrocarbons (PAHs) and planar halogenated aromatic hydrocarbons (PHAHs) such as non-ortho polychlorinated biphenyls (PCBs). In this study, we examined CYP1A1 protein expression immunohistochemically in multiple organs of beluga whales from two locations in the Arctic and from the St. Lawrence estuary. These beluga populations have some of the lowest (Arctic sites) and highest (St. Lawrence estuary) concentrations of PCBs in blubber of all cetaceans. Samples from these populations might be expected to have different contaminant-induced responses, reflecting their different exposure histories. The pattern and extent of CYP1A1 staining in whales from all three locations were similar to those seen in animal models in which CYP1A has been highly induced, indicating a high-level expression in these whales. CYP1A1 induction has been related to toxic effects of PHAHs or PAHs in some species. In St. Lawrence beluga, the high level of CYP1A1 expression coupled with high levels of contaminants (including CYP1A1 substrates, e.g., PAH procarcinogens potentially activated by CYP1A1) indicates that CYP1A1 could be involved in the development of neoplastic lesions seen in the St. Lawrence beluga population. The systemic high-level expression of CYP1A1 in Arctic beluga suggests that effects of PAHs or PHAHs may be expected in Arctic populations, as well. The high-level expression of CYP1A1 in the Arctic beluga suggests that this species is highly sensitive to CYP1A1 induction by aryl hydrocarbon receptor agonists
Interacting galaxies in the IllustrisTNG simulations - I : Triggered star formation in a cosmological context
We use the IllustrisTNG cosmological hydrodynamical simulations to investigate how the specific star formation rates (sSFRs) of massive galaxies (M-* > 10(10) M-circle dot) depend on the distance to their closest companions. We estimate sSFR enhancements by comparing with control samples that are matched in redshift, stellar mass, local density, and isolation, and we restrict our analysis to pairs with stellar mass ratios of 0.1 to 10. At small separations (similar to 15 kpc), the mean sSFR is enhanced by a factor of 2.0 +/- 0.1 in the flagship (110.7Mpc)(3) simulation (TNG100-1). Statistically significant enhancements extend out to 3D separations of 280 kpc in the (302.6Mpc)(3) simulation (TNG300-1). We find similar trends in the EAGLE and Illustris simulations, although their sSFR enhancements are lower than those in TNG100-1 by about a factor of two. Enhancements in IllustrisTNG galaxies are seen throughout the redshift range explored (0Peer reviewe
The Atacama Cosmology Telescope: A Measurement of the Thermal Sunyaev-Zel'dovich Effect Using the Skewness of the CMB Temperature Distribution
We present a detection of the unnormalized skewness induced by the
thermal Sunyaev-Zel'dovich (tSZ) effect in filtered Atacama Cosmology Telescope
(ACT) 148 GHz cosmic microwave background temperature maps. Contamination due
to infrared and radio sources is minimized by template subtraction of resolved
sources and by constructing a mask using outlying values in the 218 GHz
(tSZ-null) ACT maps. We measure = -31 +- 6 \mu K^3 (measurement error
only) or +- 14 \mu K^3 (including cosmic variance error) in the filtered ACT
data, a 5-sigma detection. We show that the skewness is a sensitive probe of
sigma_8, and use analytic calculations and tSZ simulations to obtain
cosmological constraints from this measurement. From this signal alone we infer
a value of sigma_8= 0.79 +0.03 -0.03 (68 % C.L.) +0.06 -0.06 (95 % C.L.). Our
results demonstrate that measurements of non-Gaussianity can be a useful method
for characterizing the tSZ effect and extracting the underlying cosmological
information.Comment: 9 pages, 5 figures. Replaced with version accepted by Phys. Rev. D,
with improvements to the likelihood function and the IR source treatment;
only minor changes in the result
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