48 research outputs found

    Coccidia (Apicomplexa: Eimeriidae) of the Mammalian Order lnsectivora

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    The coccidia (protistan phylum Apicomplexa Levine, 1970) comprise a large group of obligate intracellular parasites commonly found in all classes of vertebrate hosts and in some invertebrates. This review focuses on those species within the Eimeriidae because they are among the most prevalent and speciose of all parasite groups, and there is no taxonomic summation currently available for those species that infect insectivores. All published species descriptions in the genera Cyclospora, Eimeria and Isospora that infect insectivores are reviewed and evaluated. Some of the named species are invalid, either because rules concerning the naming of new species (International Code of Zoological Nomenclature) were not followed and/or the original description was so incomplete as to be of little use; such names have been relegated to species inquirendae. The mammalian order Insectivora has seven families composed of 66 genera and 428 species. There are no coccidia described from three families: Chrysochloridae, Nesophontidae and Solenodontidae. In the Erinaceidae, only Erinaceus, Hemiechinus and Hylomys have valid coccidia described from them; in the Soricidae, only six genera, Crocidura, Suncus (Crocidurinae) andBlarina, Cryptotis, Neomys, and Sorex (Soricinae) have valid species described; in the Tenrecidae, only Hemicentetes and Setifer have valid species; and in the Talpidae, only Condylura, Mogera, Neurotrichus, Parascalops, Scalopus, Scapanus, Talpa and Urotrichus (Talpinae) have valid species described. In all, 75 eimeriid coccidia are known from insectivore hosts including 48 Eimeria, 22 Isospora and five Cyclospora species; 45 species inquirendae are noted

    Taxonomy of North American fish Eimeriidae

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    Taxonomic descriptions, line drawings, and references are given for the 30 named and 5 unnamed species of North American fish Eimeriidae. In addition, a key was developed based on available morphologic data to distinguish between similar species. Taxa are divided into two genera: Eimeria (27 species) which are tetr&sporocystic with dizoic, nonbivalved sporocysts, and Goussia (3 species) which are tetrasporocystic with dizoic, bivalved sporocysts that lack Stleda bodies and have sporocyst walls composed of two longitudinal valves. (PDF file contains 24 pages.

    Cryptosporidium muris, a Rodent Pathogen, Recovered from a Human in Perú

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    Cryptosporidium muris, predominantly a rodent species of Cryptosporidium, is not normally considered a human pathogen. Recently, isolated human infections have been reported from Indonesia, Thailand, France, and Kenya. We report the first case of C. muris in a human in the Western Hemisphere. This species may be an emerging zoonotic pathogen capable of infecting humans

    Evaluation of in vitro and in vivo activity of benzindazole-4,9-quinones against Cryptosporidium parvum

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    A series of benzindazole-4,9-quinones was tested for growth-inhibitory effects on Cryptosporidium parvum in vitro and in vivo. Most compounds showed considerable activity at concentrations from 25 to 100 µM. For instance, at 25 µM the derivatives 5-hydroxy-8-chloro-N 1 -methylbenz[f]-indazole-4,9-quinone and 5-chloro-N 2 -methylbenz[f]indazole-4,9-quinone inhibited growth of C. parvum 78-100%, and at 50 µM seven of the 23 derivatives inhibited growth ≥90%. The activity of the former two compounds was confirmed in a T-cell receptor α (TCR-α)-deficient mouse model of chronic cryptosporidiosis. In these mice, the mean infectivity scores (IS) in the caecum were 0.63-0.20, whereas in sham-treated mice the score was 1.44 (P < 0.05). There were similar differences in IS in the ileum, where the score for treated mice was 1.12-0.20 and that for mice receiving no drug was 1.32. There was no acute or chronic toxicity for any compound tested in vivo

    The Weaklaw Vent, SE Scotland:Metasomatism of eruptive products by carbo-hydro-fluids of probable mantle origin

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    This is the author accepted manuscript. The final version is available from CUP via the DOI in this record The Weaklaw vent in SE Scotland (East Lothian coast), inferred to be Namurian, produced lava spatter and volcanic bombs. The latter commonly contained ultramafic xenoliths. All were metasomatised by carbonic fluids rich in incompatible elements. The lavas and xenoliths are inferred to have been basanites and lherzolites prior to metasomatism. The abundance and size of (carbonated) peridotite xenoliths at Weaklaw denotes unusual rapidity of magma ascent and high-energy eruption making Weaklaw exceptional in the British Isles. The lavas and xenoliths were altered subsequently by low-temperature (<200°C) carbo-hydrous fluids to carbonate, clay and quartz assemblages. A small irregular tuffisite 'dyke' that transects the ejecta is also composed dominantly of carbonates and clays. The peridotitic xenoliths are typically foliated, interpreted as originating as pre-entrainment mantle shear-planes. Analyses of the relic spinels shows them to be compositionally similar to spinels in local unaltered lherzolites from near-by basanitic occurrences. Chromium showed neither significant loss nor gain but was concentrated in a di-octahedral smectite allied to volkonskoite. It is in the complex association of smectite with other clays, chlorite and possibly fuchsite that the diverse incompatible elements are concentrated. We conclude that late Palaeozoic trans-tensional fault movement caused mantle shearing. Rapid ascent of basanite magma entrained large quantities of sheared lithospheric mantle. This was followed by ascent of an aggressive carbonate-/ hydroxyl-rich fluid causing pervasive metasomatism. The vent is unique in several ways: in its remarkable clay mineralogy and in displaying such high Cr-clays in a continental intra-plate setting; in being more productive in terms of its 'cargo' of peridotite xenoliths; in presenting an essentially un-eroded sequence of Namurian extrusives; and, not least, for giving evidence for post-eruptive, surface release of small-melt, deep-source fluids

    Identification of 2-Aryl-Quinolone Inhibitors of Cytochrome bd and Chemical Validation of Combination Strategies for Respiratory Inhibitors against Mycobacterium tuberculosis

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    Mycobacterium tuberculosis cytochrome bd quinol oxidase (cyt bd), the alternative terminal oxidase of the respiratory chain, has been identified as playing a key role during chronic infection and presents a putative target for the development of novel antitubercular agents. Here, we report confirmation of successful heterologous expression of M. tuberculosis cytochrome bd. The heterologous M. tuberculosis cytochrome bd expression system was used to identify a chemical series of inhibitors based on the 2-aryl-quinolone pharmacophore. Cytochrome bd inhibitors displayed modest efficacy in M. tuberculosis growth suppression assays together with a bacteriostatic phenotype in time-kill curve assays. Significantly, however, inhibitor combinations containing our front-runner cyt bd inhibitor CK-2-63 with either cyt bcc-aa3 inhibitors (e.g., Q203) and/or adenosine triphosphate (ATP) synthase inhibitors (e.g., bedaquiline) displayed enhanced efficacy with respect to the reduction of mycobacterium oxygen consumption, growth suppression, and in vitro sterilization kinetics. In vivo combinations of Q203 and CK-2-63 resulted in a modest lowering of lung burden compared to treatment with Q203 alone. The reduced efficacy in the in vivo experiments compared to in vitro experiments was shown to be a result of high plasma protein binding and a low unbound drug exposure at the target site. While further development is required to improve the tractability of cyt bd inhibitors for clinical evaluation, these data support the approach of using small-molecule inhibitors to target multiple components of the branched respiratory chain of M. tuberculosis as a combination strategy to improve therapeutic and pharmacokinetic/pharmacodynamic (PK/PD) indices related to efficacy

    Surface rupture of multiple crustal faults in the 2016 Mw 7.8 Kaikōura, New Zealand, earthquake

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    Multiple (>20 >20 ) crustal faults ruptured to the ground surface and seafloor in the 14 November 2016 M w Mw 7.8 Kaikōura earthquake, and many have been documented in detail, providing an opportunity to understand the factors controlling multifault ruptures, including the role of the subduction interface. We present a summary of the surface ruptures, as well as previous knowledge including paleoseismic data, and use these data and a 3D geological model to calculate cumulative geological moment magnitudes (M G w MwG ) and seismic moments for comparison with those from geophysical datasets. The earthquake ruptured faults with a wide range of orientations, sense of movement, slip rates, and recurrence intervals, and crossed a tectonic domain boundary, the Hope fault. The maximum net surface displacement was ∼12  m ∼12  m on the Kekerengu and the Papatea faults, and average displacements for the major faults were 0.7–1.5 m south of the Hope fault, and 5.5–6.4 m to the north. M G w MwG using two different methods are M G w MwG 7.7 +0.3 −0.2 7.7−0.2+0.3 and the seismic moment is 33%–67% of geophysical datasets. However, these are minimum values and a best estimate M G w MwG incorporating probable larger slip at depth, a 20 km seismogenic depth, and likely listric geometry is M G w MwG 7.8±0.2 7.8±0.2 , suggests ≤32% ≤32% of the moment may be attributed to slip on the subduction interface and/or a midcrustal detachment. Likely factors contributing to multifault rupture in the Kaikōura earthquake include (1) the presence of the subduction interface, (2) physical linkages between faults, (3) rupture of geologically immature faults in the south, and (4) inherited geological structure. The estimated recurrence interval for the Kaikōura earthquake is ≥5,000–10,000  yrs ≥5,000–10,000  yrs , and so it is a relatively rare event. Nevertheless, these findings support the need for continued advances in seismic hazard modeling to ensure that they incorporate multifault ruptures that cross tectonic domain boundaries
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