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• Trimeric S, S1, COEs, and two adjuvants were selected to evaluate immune effects. • S/M103 elicited neutralizing antibodies, T cells, B cells, and NK cells in mice. • S/M103 induced high levels of neutralizing antibodies, IFN-γ, and IL-4 in piglets. • S/M103 provided protection against viral challenge in piglets. Porcine epidemic diarrhea virus (PEDV) has caused serious economic losses to the pig husbandry worldwide, and the effects of existing commercialized vaccines are suboptimal. Therefore, research to develop an efficacious vaccine for prevention and control of PEDV is essential. In this study, we designed and produced trimerized proteins of full-length PEDV spike (S) protein, S1 subunit, and a tandem of multiple epitopes of S protein using an efficient mammalian expression vector system in HEK 293F cells. The immunogenicity of two commercial adjuvants, M401 and M103, was also evaluated in mice. Enzyme-linked immunosorbent assays demonstrated that all immunized mice generated highly systemic PEDV S-specific IgG and IgA antibodies. Mice in S/M103-immunized group generated the highest neutralizing antibody titer with 1:96. Compared with control group, the subunit vaccines elicited multifunctional CD3+CD4+ and CD3+CD8+ T cells, B220+CD19+ B cells, and CD3-CD49b+ natural killer cells in the spleen. PEDV S/M103 vaccine, which had the best immune effect, was selected for further evaluation in piglets. Immunization with S/M103 vaccine induced high levels of S-specific IgG, IgA, and neutralizing antibodies, and increased the proliferation of peripheral blood mononuclear cells and the expression levels of interferon-γ and interleukin-4 in peripheral blood of piglets. Virus challenge test results showed significantly lower diarrheal index scores and fecal viral loads, and less pathological damage to the intestines in S/M103-immunized piglets than in controls, indicating that S/M103 provides good protection against the virulent virus challenge. Our findings suggest that trimeric PEDV S/M103 has potential as a clinical vaccine candidate. [ABSTRACT FROM AUTHOR]

Coronavirus disease is an emerging infection caused by a novel coronavirus that is moving rapidly. High resolution computed tomography (CT) allows objective evaluation of the lung lesions, thus enabling us to better understand the pathogenesis of the disease. With serial CT examinations, the occurrence, development, and prognosis of the disease can be better understood. The imaging can be sorted into four phases: early phase, progressive phase, severe phase, and dissipative phase. The CT appearance of each phase and temporal progression of the imaging findings are demonstrated. [ABSTRACT FROM AUTHOR]

A series of novel L-malic acid modified hyper-cross-linked resins were synthesized from macroporous chloromethylated styrene-divinylbenzene copolymer by Fridel–Crafts reaction and esterification reaction. The adsorption behavior of the resin toward p-aminobenzoic acid was investigated from aqueous solution. KZ-3 displayed the most outstanding adsorption capacity due to its proper surface structure and higher functional group utilization rate. Subsequently, the adsorption kinetic of p-aminobenzoic acid onto precursor resin Z-3, modified resin KZ-3 and commercially available polymeric adsorbent H-103 was compared. The result demonstrated that KZ-3 had the optimal adsorption capacity because of its hydrogen bonding driving force and hydrophilicity enhancement which brought by oxygen-containing functional groups. Especially, KZ-3 is 3 times higher than the precursor resin in terms of adsorption rate. Kinetic curves could be characterized by pseudo-second-order rate equation and both the intra-particle diffusion and the film diffusion were the rate-limiting steps. The isotherms could be fitted by Langmuir model and the adsorption was an exothermic, spontaneous and more ordered arrangement process due to its negative thermodynamic parameters. [ABSTRACT FROM AUTHOR]

Chalcone synthase (CHS) is the pivotal enzyme that catalyzes the first committed step of the phenylpropanoid pathway leading to flavonoids. Here, five CHS genes were determined in mulberry ( Morus atropurpurea Roxb.). Interestingly, phylogenetic analysis tended to group three MaCHSs in the stilbene synthase (STS) family and initially annotated these as MaSTSs. A co-expression system that harbored a 4-coumarate:CoA ligase gene and one of the candidate genes was established to determine the functions of this novel gene family. The fermentation result demonstrated that MaSTS in fact encoded a CHS enzyme, and was consequently retermed MaCHS . Tissue-specific expression analysis indicated that MaCHS1 / MaCHS2 was highly abundant in fruit, and MaCHS4 had significant expression in root bark, stem bark and old leaves, while MaCHS3 and MaCHS5 were more expressed in old leaves. Subcellular localization experiments showed that MaCHS was localized to the cytoplasm. Transcription levels suggested MaCHS genes were involved in a series of defense responses. Over-expression of MaCHS in transgenic tobacco modified the metabolite profile, and resulted in elevated tolerance to a series of environmental stresses. This study comprehensively evaluated the function of MaCHS genes and laid the foundation for future research on MaCHS in mulberry. [ABSTRACT FROM AUTHOR]

A cellulase gene ( KJ700939 , CsCelA ) from Ciboria shiraiana that is highly expressed during the infection of mulberry fruit was screened by quantitative real-time PCR (qRT-PCR). Using cDNA isolated from infected mulberry fruits as template, the full-length 1170-bp sequence of CsCelA was obtained, which encodes a 390-amino acid protein with a putative signal peptide of 24 amino acids. The 998-bp fragment encoding the mature peptide of CsCelA was cloned into the multiple cloning site of the pPIC9K vector and overexpressed as an active protein of 55.3 kDa in the methylotrophic yeast Pichia pastoris . The specific activity of induced supernatants of the recombinant cellulase (CsCelA) was 17.44 U/ml and 135 U/g for freeze-dried powder. The K max and V max of CsCelA for sodium carboxymethylcellulose (CMC) were 4.6 mg/ml and 107.2 U/mg, respectively. The supernatant and freeze-dried powder of the recombinant cellulase exhibited stable activity from pH 4.0 to 9.0, and at temperatures ranging from 30 °C to 55 °C. Finally, the activity of the recombinant cellulase was assessed by enzymatic hydrolysis of the cell walls of mulberry leaves. CsCelA showed an endo-cellulase mode of cleavage, as assessed by thin layer chromatography (TLC). [ABSTRACT FROM AUTHOR]

Abstract: Pressure drops are measured on different nozzles of various pipe sizes in dense phase pulverized coal pneumatic conveying. From the experimental results, we conclude that the effect of the gas phase nozzle pressure drop is negligible when comparing with the solid phase pressure drop in the experimental range. The main influence factors contributing to the nozzle pressure drop are gas and solid mass flow rate, solids loading ratio, and the diameters of the nozzle inlet and outlet. A new model was developed to predict the nozzle pressure drop in dense phase pneumatic conveying of pulverized coal based on the Barth''s pneumatic conveying theory. The pressure drop predictions from the model are in good agreement with the experimental values. The model quantified the important influence factors of the nozzle pressure drop. [Copyright &y& Elsevier]

Purpose: To evaluate the diagnostic value of computed tomography (CT) and real-time reverse-transcriptase-polymerase chain reaction (rRT-PCR) for COVID-19 pneumonia.Methods: This retrospective study included all patients with COVID-19 pneumonia suspicion, who were examined by both CT and rRT-PCR at initial presentation. The sensitivities of both tests were then compared. For patients with a final confirmed diagnosis, clinical and laboratory data, in addition to CT imaging findings were evaluated.Results: A total of 36 patients were finally diagnosed with COVID-19 pneumonia. Thirty-five patients had abnormal CT findings at presentation, whereas one patient had a normal CT. Using rRT-PCR, 30 patients were tested positive, with 6 cases initially missed. Amongst these 6 patients, 3 became positive in the second rRT-PCR assay(after 2 days, 2 days and 3 days respectively), and the other 3 became positive only in the third round of rRT-PCR tests(after 5 days, 6 days and 8 days respectively). At presentation, CT sensitivity was therefore 97.2%, whereas the sensitivity of initial rRT-PCR was only 83.3%.Conclusion: rRT-PCR may produce initial false negative results. We suggest that patients with typical CT findings but negative rRT-PCR results should be isolated, and rRT-PCR should be repeated to avoid misdiagnosis. [ABSTRACT FROM AUTHOR]