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31.
Mathieu Lefèvre Daniel J. Felmlee Marie Parnot Thomas F. Baumert Catherine Schuster 《PloS one》2014,9(4)
Hepatitis C virus (HCV) is a major cause of liver disease worldwide and HCV infection represents a major health problem. HCV associates with host lipoproteins forming host/viral hybrid complexes termed lipoviral particles. Apolipoprotein E (apoE) is a lipoprotein component that interacts with heparan sulfate proteoglycans (HSPG) to mediate hepatic lipoprotein uptake, and may likewise mediate HCV entry. We sought to define the functional regions of apoE with an aim to identify critical apoE binding partners involved in HCV infection. Using adenoviral vectors and siRNA to modulate apoE expression we show a direct correlation of apoE expression and HCV infectivity, whereas no correlation exists with viral protein expression. Mutating the HSPG binding domain (HSPG-BD) of apoE revealed key residues that are critical for mediating HCV infection. Furthermore, a novel synthetic peptide that mimics apoE’s HSPG-BD directly and competitively inhibits HCV infection. Genetic knockdown of the HSPG proteins syndecan (SDC) 1 and 4 revealed that SDC4 principally mediates HCV entry. Our data demonstrate that HCV uses apoE-SDC4 interactions to enter hepatoma cells and establish infection. Targeting apoE-SDC interactions could be an alternative strategy for blocking HCV entry, a critical step in maintaining chronic HCV infection. 相似文献
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J. Tertius Clarke 《BMJ (Clinical research ed.)》1933,1(3758):78-79
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Vasily V Grebennikov † Alberto Ballerio Clarke H Scholtz 《Australian Journal of Entomology》2002,41(4):367-374
Abstract Pupae and mature larvae of the Australian ceratocanthid beetle, Cyphopisthes descarpentriesi Paulian 1977, are described and extensively illustrated. This is the sixth species of the family for which immature stages are known and the first from the Australian region. Unlike other ceratocanthid larvae described before, those of Cyphopisthes Gestro lack stridulatory teeth on the middle and hind legs and any trace of a frontoclypeal suture on the cranium. Reduced one-segmented labial palpi in Cyphopisthes are unique in Scarabaeoidea. Monophyly of the family is not corroborated by larval characters. Absence of spiracular closing apparatus in larvae is reported in the family for the first time. Like pupae of Ceratocanthus White and Germarostes Paulian, those of Cyphopisthes have thoracic projections, but their shape and location are different. Spiracles are found on abdominal segments 2−4 of pupa; that on segment 2 differs in colour and location from the others. 相似文献
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Decapod crustaceans are relatively widespread in Jurassic deposits of Europe and a small number have been collected from the north-east of France. A new fossil of a macrurous decapod assigned to Eryma burgundiaca sp. nov., an erymid lobster, is described from this area and comparisons are made with closely allied species from Europe. Probable pagurid anomurous decapods are represented by Orhomalus magnificus sp. nov., Palaeopagurus acutus sp. nov. and Palaeopagurus neraudeaui sp. nov. No brachyurous decapods are presently known from the fauna. Based on the associated ammonites, the material is considered to be Callovian in age. 相似文献
39.
Moran Jonathan A.; Merbach Marlis A.; Livingston Nigel J.; Clarke Charles M.; Booth Webber E. 《Annals of botany》2001,88(2):307-311
Old World pitcher plants (Nepenthes spp., Nepenthaceae) trapand digest invertebrate prey to derive nutrients, primarilynitrogen (N). In the majority of lowland Nepenthes species studiedto date, ants (Hymenoptera, Formicidae) are numerically thedominant prey taxon. Nepenthes albomarginata is unusual in showingan apparent bias towards the capture of termites (Isoptera).We tested the hypothesis that N. albomarginata derives N fromtermite capture, by comparison of foliar stable N isotope abundance( 相似文献