【摘要】Protease inhibitors have been reported rarely fromthe leech Hirudinaria manillensis. In this study, wepurified a novel protease inhibitor （bdellin-HM-2） withanticoagulant properties from H. manillensis. With amolecular weight of 1.4x104, bdellin-HM-2 was alsocharacterized with three intra-molecular disulfidebridges at the N-terminus and multiple HHXDD andHXDDmotifs at the C-terminus. cDNAcloning revealedthat the putative nucleotide-encoding protein ofbdellin-HM-2 contained 132 amino acids and wasencoded by a 399 bp open reading frame （ORF）。 Sequence alignment showed that bdellin-HM-2 sharedsimilarity with the“non-classical”Kazal-type serineprotease inhibitors, but had no inhibitory effect ontrypsin, elastase, chymotrypsin, kallikrein, factor XIIa（FXIIa）， factor XIa （FXIa）， factor Xa （FXa）， thrombin,or plasmin. Bdellin-HM-2 showed anticoagulant effectsby prolonging the activated partial thromboplastin time（aPTT）， indicating a role in enabling H. manillensis toobtain a blood meal from its host. Our resultssuggest that bdellin-HM-2 may play a crucial role inblood-sucking in this leech species and may be apotential candidate for the development of clinicalanti-thrombotic drugs.
《动物学研究》 | 2019年3期 | Ruo-Mei Cheng
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【摘要】Ultraviolet-visible and nuclear magnetic resonance (NMR) spectroscopy was used to investigate the effects of pH, solvent and temperature on the tautomeric equilibrium of selaginellins from Selaginella. The results demonstrated that the tautomerism of selaginellins could be catalyzed by acid, base and protic solvent. Variable-temperature 1HNMRexperiments demonstrated that the tautomerism was interrupted when the temperature fell below 233 K.
《波谱学杂志》 | 2019年2期 | CAOYuan
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【摘要】The Angolan strain of Marburg virus （MARV/Ang） can cause lethal disease in humans with a case fatality rate of up to 90%, but infection of immunocompetent rodents do not result in any observable symptoms. Our previous work includes the development and characterization of a MARV/Ang variant that can cause lethal disease in mice （MARV/Ang-MA）， with the aim of using this tool to screen for promising prophylactic and therapeutic candidates. An intermediate animal model is needed to confirm any findings from mice studies before testing in the gold-standard non-human primate （NHP） model. In this study, we serially passaged the clinical isolate of MARV/Ang in the livers and spleens of guinea pigs until a variant emerged that causes 100% lethality in guinea pigs （MARV/Ang-GA）。 Animals infected with MARV/Ang-GA showed signs of filovirus infection including lymphocytopenia, thrombocytopenia, and high viremia leading to spread to major organs, including the liver, spleen, lungs, and kidneys. The MARV/Ang-GA guinea pigs died between 7-9 days after infection, and the LD50 was calculated to be 1.1×10-1 TCID50 （median tissue culture infective dose）。 Mutations in MARV/Ang-GA were identified and compared to sequences of known rodent-adapted MARV/Ang variants, which may benefit future studies characterizing important host adaptation sites in the MARV/Ang viral genome.
《动物学研究》 | 2018年1期 | Gary Wong
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【摘要】<p>Colony-stimulating factor 1 receptor (CSF-1R) is an<br/>important regulator of monocytes/macrophages<br/>(MO/MΦ). Although several CSF-1R genes have<br/>been identified in teleosts, the precise role of CSF-<br/>1R in ayu (Plecoglossus altivelis) remains unclear. In<br/>this study, we characterized the CSF-1R homologue<br/>from P. altivelis, and named it PaCSF-1R. Multiple<br/>sequence alignment and phylogenetic tree analysis<br/>showed that PaCSF-1R was most closely related to<br/>that of Japanese ricefish (Oryzias latipes). Tissue<br/>distribution and expression analysis showed that<br/>the PaCSF-1R transcript was mainly expressed in<br/>the head kidney-derived MO/MΦ, spleen, and<br/>head kidney, and its expression was significantly<br/>altered in various tissues upon Vibrio anguillarum<br/>infection. After PaCSF-1R neutralization for 48 h,<br/>the phagocytic activity of MO/MΦ was significantly<br/>decreased, suggesting that PaCSF-1R plays a<br/>role in regulating the phagocytic function of ayu<br/>MO/MΦ.</p>
《动物学研究》 | 2016年2期 | Qiang CHEN
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【摘要】Based on morphological and genetic evidence weevaluated the taxonomic status of a newly discoveredforest-dwelling population of skink (genus Scincella)from the Keo Seima Wildlife Sanctuary, MondulkiriProvince, Cambodia. From phylogenetic analysis of a668-bp fragment of the mtDNA COI and diagnosticmorphological characters we allocate the newlydiscovered population to the Scincella reevesii–S. rufocaudata species complex and describe it asScincella nigrofasciata sp. nov. The new skinkspecies can be distinguished from all other SoutheastAsian congeners by the following combination ofmorphological characters: snout-vent length (SVL)40.0–52.6 mm; relative tail length (TaL/SVL ratio)1.25–1.94; prefrontals in broad contact; infralabials 6;primary temporals 2; relative forelimb length (FIL/SVLratio) 0.20–0.22; relative hindlimb length (HIL/SVLratio) 0.30–0.33; relative forearm length (FoL/SVLratio) 0.14–0.16; adpressed forelimbs and hind limbseither overlapping (0.4–2.2 mm) or separated (1.9–2.3mm); midbody scale rows 32–33, paravertebral scales69–74, vertebral scales 65–69; dorsal scales betweendorsolateral stripes 8; comparatively slender fingersand toes, subdigital lamellae under fourth toe 15–17;dark discontinuous regular dorsal stripes 5–7; distinctblack dorsolateral stripes, narrowing to lateral sidesand extending to 52%–86% of total tail length. Weprovide additional information on the holotype ofScincella rufocaudata (Darevsky & Nguyen, 1983), andprovide evidence for the species status of Scincellarupicola. Our discovery brings the number of Scincellaspecies in Cambodia to five and emphasizes theincompleteness of knowledge on the herpetofaunaldiversity of this country.
《动物学研究》 | 2018年3期 | Thy Neang
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【摘要】This paper aims to find out the roots of discriminations towards the Asian Americans from a historical point of view, aims to give people a true picture of the current conditions of the Asians in America, which may be different from what people have imagined. In this way, there may be more attentions drawn to the special group, which tenaciously survives and thrives.
《长江丛刊》 | 2016年19期 | 牛筱萌
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【摘要】Species of Xenophrys are conserved morphologically and liveprimarily in forests. In Thailand, the genus harbors manycryptic species. Herein we report the collection of specimensfrom Doi Inthanon, Chiang Mai Province, northern Thailand,which were identified previously as X. minor. Molecular andmorphological analyses find that these specimens differsignificantly from other known congeners, and therefore wedescribe a new species. Further, our phylogenetic analysesindicate that X. latidactyla is a junior synonym of X. palpebralespinosa.
《动物学研究》 | 2019年6期 | Yun-He Wu
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