Molecular characterization of cathepsin B from Clonorchis sinensis excretory/secretory products and assessment of its potential for serodiagnosis of clonorchiasis

<p>Abstract</p> <p>Background</p> <p>Cathepsin cysteine proteases play multiple roles in the life cycle of parasites such as food uptake, immune invasion and pathogenesis, making them valuable targets for diagnostic assays, vaccines and drugs. The purpose of this study was to identify a cathepsin B of <it>Clonorchis sinensis </it>(<it>Cs</it>CB) and to investigate its diagnostic value for human helminthiases.</p> <p>Results</p> <p>The predicted amino acid sequence of the cathepsin B of <it>C. sinensis </it>shared 63%, 52%, 50% identity with that of <it>Schistosoma japonicum</it>, <it>Homo sapiens </it>and <it>Fasciola hepatica</it>, respectively. Sequence encoding proenzyme of <it>Cs</it>CB was overexpressed in <it>Escherichia coli</it>. Reverse transcription PCR experiments revealed that <it>Cs</it>CB transcribed in both adult worm and metacercaria of <it>C. sinensis</it>. <it>Cs</it>CB was identified as a <it>C. sinensis </it>excretory/secretory product by immunoblot assay, which was consistent with immunohistochemical localization showing that <it>Cs</it>CB was especially expressed in the intestine of <it>C. sinensis </it>adults. Both ELISA and western blotting analysis showed recombinant <it>Cs</it>CB could react with human sera from clonorchiasis and other helminthiases.</p> <p>Conclusions</p> <p>Our findings revealed that secreted CsCB may play an important role in the biology of C. sinensis and could be a diagnostic candidate for helminthiases.</p

Synthesis, Crystal Structure, and Electrochemical Properties of an Isopolyoxovanadate Compound Modified Transition-Metal Complex Based on [V₄O₁₂]⁴⁻

A new isopolyoxovanadate compound [Zn(phen)3]2·(V4O12)·phen·20H2O (phen = 1,10-phenathroline) (1) has been synthesized in aqueous solution and characterized using IR and UV/Vis spectroscopy, elemental analysis, thermal gravimetric analysis, powder, single-crystal X-ray diffractions, and field emission scanning electron microscopy. The molecular structure of 1 exists as two kinds of [V4O12]4− polyoxoanions: distorted chair-like and coplanar conformations, two independent [Zn(phen)3]2+ units and free phen. In the solid state, compound 1 forms a stable three-dimensional supramolecular structure through electrostatic interactions, π–π stacking interactions and multiform hydrogen bonds. The electrocatalytic activity and determination of DA of compound 1 have been studied by cyclic voltammetry and differential pulse voltammetry, respectively

Multistep Transformations of DNA Origami Domino Array via Mechanical Forces

Nanostructures that display controllable motions and functions are indispensable to build molecular nanomachines. Structural DNA nanotechnology, enabling precise design of complex static and dynamic structures, can be used to construct molecular nanomachines. However, designing complex dynamic structures that present multiple motion behaviors with different stimuli‐responsiveness is full of challenges. Herein, multistep transformations of DNA origami domino array (DODA) triggered by mechanical forces are developed. The DODA consists of small, modular DNA units, which can be regulated by the external forces. Under the expanding and contraction forces exerted by the DNA trigger and G‐quadruplex (G4)‐functionalized loop strand, the units are reconfigured, leading to the programmable transformations of DODA among three conformations. This multistep transformation strategy is applied to construct chiral plasmonic metamolecules, and analyze K+ via fluorescence resonance energy transfer (FRET) analysis. Moreover, the strategy shows a diversified approach to build the DNA‐based nanodevices, and may find potential applications in various fields

Efficacy and safety of Fufang Furong Effervescent Suppository for the treatment of mixed vaginitis: a randomized, multicenter, and non-inferiority study

Objective: The aim of this study was to compare the clinical efficacy and safety of Fufang Furong Effervescent Suppository and clindamycin phosphate cream for the treatment of bacterial vaginosis (BV) combined with aerobic vaginitis (AV). Methods: This was a randomized, multicentre, active-controlled, non-inferiority clinical trial, with two parallel groups. Women diagnosed with BV + AV were randomly assigned to one of two groups and received 12-days of vaginal administration of either Fufang Furong Effervescent Suppository or clindamycin phosphate cream. The follow-up occurred during the 3–5 days (15–17 days) and 28 ± 3 days (40 ± 3 days) after drug administration, with the main assessments including the cure rate, BV, AV effective rate, recurrence rate, Lactobacillary grade (LBG) changes and adverse effects. The non-inferiority threshold of the non-inferiority test was set at 12%. Results: From among the 600 eligible participants, 559 were randomly allocated to either the Furong group (n = 285) or the Clindamycin group (n = 274). The cure rate, BV, AV effective rate and the LBG changes of Furong group were not inferior to Clindamycin group in 15–17 days. The recurrence rate of BV + AV was also non-inferior to Clindamycin group at 40±3 days. During the follow-up period, no significant difference in the incidence of side effects were found between the two groups. Conclusion: The treatment of BV + AV using Fufang Furong Effervescent Suppository was not inferior to that of clindamycin phosphate cream in terms of cure rate, LBG changes, recurrence rate and adverse effects