1,959 research outputs found

    Target product profiles for protecting against outdoor malaria transmission.

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    BACKGROUND\ud \ud Long-lasting insecticidal nets (LLINs) and indoor residual sprays (IRS) have decimated malaria transmission by killing indoor-feeding mosquitoes. However, complete elimination of malaria transmission with these proven methods is confounded by vectors that evade pesticide contact by feeding outdoors.\ud \ud METHODS\ud \ud For any assumed level of indoor coverage and personal protective efficacy with insecticidal products, process-explicit malaria transmission models suggest that insecticides that repel mosquitoes will achieve less impact upon transmission than those that kill them outright. Here such models are extended to explore how outdoor use of products containing either contact toxins or spatial repellents might augment or attenuate impact of high indoor coverage of LLINs relying primarily upon contact toxicity.\ud \ud RESULTS\ud \ud LLIN impact could be dramatically enhanced by high coverage with spatial repellents conferring near-complete personal protection, but only if combined indoor use of both measures can be avoided where vectors persist that prefer feeding indoors upon humans. While very high levels of coverage and efficacy will be required for spatial repellents to substantially augment the impact of LLINs or IRS, these ambitious targets may well be at least as practically achievable as the lower requirements for equivalent impact using contact insecticides.\ud \ud CONCLUSIONS\ud \ud Vapour-phase repellents may be more acceptable, practical and effective than contact insecticides for preventing outdoor malaria transmission because they need not be applied to skin or clothing and may protect multiple occupants of spaces outside of treatable structures such as nets or houses

    Diphyllobothriasis in a nine-year-old child in India: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>The <it>Diphyllobothrium </it>genus belongs to the <it>Diphyllobothridea </it>order of tapeworms. <it>Diphyllobothrium </it>spp., which is commonly known as fish tapeworm, is generally transmitted in humans, but also in other species, such as bears, dogs, cats, foxes, and other terrestrial carnivores. Although worldwide in distribution, the original heartland of <it>Diphyllobothrium </it>spp. spreads across Scandinavia, northern Russia, and western Serbia. We report a rare case that occurred in India.</p> <p>Case presentation</p> <p>A nine-year-old south Indian girl was brought to the casualty at the Prathima Institute of Medical Sciences with complaints of vomiting and loose stools that had started three days earlier. The vomit did not have a foul smell and contained no blood or mucus, but it did contain undigested food particles. The patient described a history of recurrent abdominal pain. She was a non-vegetarian and said she had a history of eating fish.</p> <p>Conclusion</p> <p>The incidence of <it>Diphyllobothrium </it>spp. infection is infrequent in India. Since this is only the fourth reported case in India, and since the previously reported cases also involved observed pediatric patients, we emphasize the need for clinical microbiologists and pediatricians to suspect fish tapeworm infection and recommend epidemiological study of <it>Diphyllobothrium </it>spp. infection.</p

    P113 is a merozoite surface protein that binds the N terminus of Plasmodium falciparum RH5.

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    Invasion of erythrocytes by Plasmodium falciparum merozoites is necessary for malaria pathogenesis and is therefore a primary target for vaccine development. RH5 is a leading subunit vaccine candidate because anti-RH5 antibodies inhibit parasite growth and the interaction with its erythrocyte receptor basigin is essential for invasion. RH5 is secreted, complexes with other parasite proteins including CyRPA and RIPR, and contains a conserved N-terminal region (RH5Nt) of unknown function that is cleaved from the native protein. Here, we identify P113 as a merozoite surface protein that directly interacts with RH5Nt. Using recombinant proteins and a sensitive protein interaction assay, we establish the binding interdependencies of all the other known RH5 complex components and conclude that the RH5Nt-P113 interaction provides a releasable mechanism for anchoring RH5 to the merozoite surface. We exploit these findings to design a chemically synthesized peptide corresponding to RH5Nt, which could contribute to a cost-effective malaria vaccine

    Culex genome is not just another genome for comparative genomics

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    Formal publication of the Culex genome sequence has closed the human disease vector triangle by meeting the Anopheles gambiae and Aedes aegypti genome sequences. Compared to these other mosquitoes, Culex quinquefasciatus possesses many specific hallmark characteristics, and may thus provide different angles for research which ultimately leads to a practical solution for controlling the ever increasing burden of insect-vector-borne diseases around the globe. We argue the special importance of the cosmopolitan species- Culex genome sequence by invoking many interesting questions and the possible of potential of the Culex genome to answer those

    Shocked monazite chronometry: integrating microstructural and in situ isotopic age data for determining precise impact ages

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    Monazite is a robust geochronometer and occurs in a wide range of rock types. Monazite also records shock deformation from meteorite impact but the effects of impact-related microstructures on the U–Th–Pb systematics remain poorly constrained. We have, therefore, analyzed shock-deformed monazite grains from the central uplift of the Vredefort impact structure, South Africa, and impact melt from the Araguainha impact structure, Brazil, using electron backscatter diffraction, electron microprobe elemental mapping, and secondary ion mass spectrometry (SIMS). Crystallographic orientation mapping of monazite grains from both impact structures reveals a similar combination of crystal-plastic deformation features, including shock twins, planar deformation bands and neoblasts. Shock twins were documented in up to four different orientations within individual monazite grains, occurring as compound and/or type one twins in (001), (100), (10 1 ¯) , {110}, { 212 } , and type two (irrational) twin planes with rational shear directions in [ 0 1 ¯ 1 ¯ ] and [ 1 ¯ 1 ¯ 0 ]. SIMS U–Th–Pb analyses of the plastically deformed parent domains reveal discordant age arrays, where discordance scales with increasing plastic strain. The correlation between discordance and strain is likely a result of the formation of fast diffusion pathways during the shock event. Neoblasts in granular monazite domains are strain-free, having grown during the impact events via consumption of strained parent grains. Neoblastic monazite from the Inlandsee leucogranofels at Vredefort records a 207Pb/206Pb age of 2010 ± 15 Ma (2σ, n = 9), consistent with previous impact age estimates of 2020 Ma. Neoblastic monazite from Araguainha impact melt yield a Concordia age of 259 ± 5 Ma (2σ, n = 7), which is consistent with previous impact age estimates of 255 ± 3 Ma. Our results demonstrate that targeting discrete microstructural domains in shocked monazite, as identified through orientation mapping, for in situ U–Th–Pb analysis can date impact-related deformation. Monazite is, therefore, one of the few high-temperature geochronometers that can be used for accurate and precise dating of meteorite impacts
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