Neutralizing antibodies targeting a novel epitope on envelope protein exhibited broad protection against flavivirus without risk of disease enhancement.

BACKGROUND: Flavivirus causes many serious public health problems worldwide. However, licensed DENV vaccine has restrictions on its use, and there is currently no approved ZIKV vaccine. Development of a potent and safe flavivirus vaccine is urgently needed. As a previous study revealed the epitope, RCPTQGE, located on the bc loop in the E protein domain II of DENV, in this study, we rationally designed and synthesized a series of peptides based on the sequence of JEV epitope RCPTTGE and DENV/ZIKV epitope RCPTQGE. METHODS: Immune sera were generated by immunization with the peptides which were synthesized by using five copies of RCPTTGE or RCPTQGE and named as JEV-NTE and DV/ZV-NTE. Immunogenicity and neutralizing abilities of JEV-NTE or DV/ZV-NTE-immune sera against flavivirus were evaluated by ELISA and neutralization tests, respectively. Protective efficacy in vivo were determined by passive transfer the immune sera into JEV-infected ICR or DENV- and ZIKV-challenged AG129 mice. In vitro and in vivo ADE assays were used to examine whether JEV-NTE or DV/ZV-NTE-immune sera would induce ADE. RESULTS: Passive immunization with JEV-NTE-immunized sera or DV/ZV-NTE-immunized sera could increase the survival rate or prolong the survival time in JEV-challenged ICR mice and reduce the viremia levels significantly in DENV- or ZIKV-infected AG129 mice. Furthermore, neither JEV -NTE- nor DV/ZV-NTE-immune sera induced antibody-dependent enhancement (ADE) as compared with the control mAb 4G2 both in vitro and in vivo. CONCLUSIONS: We showed for the first time that novel bc loop epitope RCPTQGE located on the amino acids 73 to 79 of DENV/ZIKV E protein could elicit cross-neutralizing antibodies and reduced the viremia level in DENV- and ZIKV-challenged AG129 mice. Our results highlighted that the bc loop epitope could be a promising target for flavivirus vaccine development.

Impact of Financing Constraints on Firm Performance: Moderating Effect Based on Firm Size.

This paper selects the relevant data of Shanghai and Shenzhen NG listed companies from 2016 to 2020 as the research object. By drawing on relevant research results at home and abroad, the variable KZ is used to measure the degree of corporate financing constraints, and the variable Tobin Q is used to measure corporate performance. The test draws the following conclusions: financing constraints are conducive to improving corporate performance. The reason is that the higher the degree of corporate financing constraints is, the more cautious the managers are in the use of funds, and the company managers can formulate more scientific management strategies, so as to improve corporate performance. Through further research, it is found that, with the expansion of the scale of the enterprise, the degree of financing constraints has less negative impact on the performance of the enterprise. Performance has a positive impact. According to the above conclusions, the government should improve the financial market system, build a multilevel capital market, and fundamentally ease the financing constraints of enterprises, to develop and improve self-management.

Evaluation of the safety and efficacy of a Fuling-Zexie decoction for people with asymptomatic hyperuricemia: protocol for a prospective, double-blinded, randomized, placebo-controlled clinical trial.

BACKGROUND: Hyperuricemia increases the risk of gout and cardiovascular complications, and how to manage asymptomatic hyperuricemia is controversial. Randomized controlled trials and comparative studies are needed to guide management and treatment. Studies show that Chinese medicine can decrease uric acid through multiple targets, but many of these studies have been conducted in animals because of the lack of a consistent prescription and mechanism. Therefore, we designed this research to study whether Chinese medicine is truly effective and which target is essential by using an approved prescription of a Fuling-Zexie decoction to further guide large sample experiments to determine whether Chinese medicine can reduce the long-term incidence of gout and cardiovascular events. METHODS: This pilot study is a prospective, double-blinded, randomized, placebo-controlled clinical trial developed from March 2020 to December 2021. Thirty people with asymptomatic hyperuricemia will be recruited and assigned to either the Chinese medicine group or placebo group, and each group will have 15 subjects. During the 12-week observation period, there will be 4 visits. The decline in uric acid is the main outcome measure, and urinary uric acid, inflammatory biomarkers, and other indices that may be involved in lowering uric acid are the secondary outcome measures. DISCUSSION: This study will probe the effect of Chinese medicine treatment on hyperuricemia and explore possible therapeutic mechanisms. By performing this trial, we hope to provide evidence and data to support further large clinical studies. TRIAL REGISTRATION: ChiCTR2000038575 . Registered on September 24, 2020.

Research on the deactivation mechanism of a denitration catalyst WO3-V2O5/TiO2 at a coal-fired power plant.

The spent and fresh V2O5-WO3/TiO2 monolith catalysts were collected from a coal-fired power plant. The de-NO x efficiency dropped by 20% after the fresh catalyst was used for 30 000 h. Then, the catalysts and the fly ash attached to spent catalysts were collected and analyzed. It was found that the relative amount of Si and Al increased by 80.84% and 2.26 times, respectively, which indicated that a lot of sediments deposited on the surface of the catalyst. Moreover, the content of Na, K, Ca and Fe increased in different degrees. A few new elements, such as Cl, Zn and Pb, appeared on the surface of the deactivated catalyst, and all of these elements had bad effects on the activity. Some kinds of ammonium salts and sulfates emerged on the fly ash, which showed that the catalysts were poisoned by SO2. The special area decreased only by 4.39 m2 g-1. The V3+/(V4+ + V5+) ratio in the catalyst increased from 0.09 to 0.45 after deactivation, and V4+ decreased by about 39.54%, which caused the deactivation of the catalyst. The surface acidity of the deactivated catalyst decreased a lot, which might be the immediate cause of deactivation. The particle size of TiO2 increased due to sintering. The main causes for the deactivation may be described as active sites decreased, poisoned and covered.

The Bone-Protecting Efficiency of Chinese Medicines Compared With Western Medicines in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis of Comparative Studies.

Background: Rheumatoid Arthritis (RA) is a systemic autoimmune disease leading to joint destruction. The prevention of bone and cartilage destruction has received increased attention in recent years. Objective: To evaluate the current evidences regarding the bone-protecting efficacy of Chinese medicine or the combination of Chinese medicine and Western medicine for RA. Methods: We comprehensively searched PubMed, Embase, the Cochrane Library (www.thecochranelibrary.com), the China National Knowledge Infrastructure (CNKI), the Database for Chinese Technical Periodicals (VIP), and SinoMed. We then performed a systematic review and cumulative meta-analysis of all randomized controlled trials (RCTs) assessing the two therapy methods. Results: Sixteen studies including 1,171 patients were included in the final analysis. The results showed that Chinese medicine could significantly improve the bone mineral density (BMD) (mean difference [MD] = 0.05 /g·cm-2, 95% CI [0.03, 0.08], P < 0.00001), and decrease the serum matrix metalloproteinase 3 (MMP-3) ([SMD] = -2.84, 95% CI [-4.22, -1.47], P < 0.0001). Conclusions: Chinese medicine may provide an efficiently alternative choice for the treatment of RA in terms of the bone-protecting efficiency. Given the inherent limitations of the included studies, future well-designed RCTs are required to confirm and update the findings of this analysis.

Fabrication and Performance of Noble Metal Promoted Birnessite Catalysts for Complete Oxidation of Formaldehyde at Low Temperatures.

Noble metal (Au, Ag, Pd and Pt) promoted birnessite (Bir) catalysts were successfully prepared and tested for catalytic oxidation of formaldehyde (HCHO). The catalysts were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), hydrogen temperature programmed reduction (H2-TPR), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and N2 adsorption-desorption. The activities of noble metal (Au, Ag, Pd and Pt) promoted birnessite catalysts follow the order of 1.0Pt/Bir > 1.0Pd/Bir > Bir > 1.0Ag/Bir > 1.0Au/Bir, revealing that the loading of Pd and Pt improves the catalytic activity of birnessite, but the loading of Ag and Au slightly decreases the catalytic activity of birnessite. Effects of the Pt loading amount were also investigated on the activity of Pt/Bir catalysts for HCHO oxidation. Pt/Bir with a Pt loading of 1.5 wt% (1.5 Pt/Bir), which has the best reduction properties, was found to be the most efficient catalyst. Over this catalyst, HCHO could be completely oxidized into CO2 and H2O at 70°. 1.5 Pt/Bir also shows good catalytic stability under the HCHO oxidation atmosphere. The differences in the catalytic activity of these materials are largely attributed to their reducibility as well as the dispersion of metal nanoparticles, but are not directly related to their specific surface areas.

Conductive Polymer Porous Film with Tunable Wettability and Adhesion.

A conductive polymer porous film with tunable wettability and adhesion was fabricated by the chloroform solution of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyricacid-methyl-ester (PCBM) via the freeze drying method. The porous film could be obtained from the solution of 0.8 wt%, whose pore diameters ranged from 50 nm to 500 nm. The hydrophobic porous surface with a water contact angle (CA) of 144.7° could be transferred into a hydrophilic surface with CA of 25° by applying a voltage. The water adhesive force on the porous film increased with the increase of the external voltage. The electro-controllable wettability and adhesion of the porous film have potential application in manipulating liquid collection and transportation.

Enhanced formaldehyde oxidation on Pt/MnO2 catalysts modified with alkali metal salts.

Novel Pt/MnO2 catalysts modified with alkali metal salts were prepared and exhibited excellent catalytic activity for formaldehyde oxidation. The effects of both cation and anion in the salts were investigated on the structure of catalysts and their catalytic activity. The Na(+) modification was demonstrated to be a facile and effective method to improve the catalysts performance for formaldehyde oxidation, but the anions remaining on the support might act as a mild poison by covering the surface active sites of manganese oxides. The enhancing effect of anions in the salts follows the order of CO3(2-)>SO4(2-)>NO3(-). A 100% formaldehyde conversion can be obtained at 50°C over the Na2CO3-modified catalyst. Further analyses indicate that strong metal-support interaction, well-dispersed Pt nanoparticles with small particle sizes and large surface area are important for high catalytic activity.

Solution fabrication of large-area Si/TiO2 core/shell nanowire arrays modified by Au nanoparticles with high photoactivity for solar water splitting.

Large-area Si/TiO2 core/shell nanowire arrays were prepared for the first time by solution approach, followed by annealing in Ar (SiNWs/TiO2-Ar) and air (SiNWs/TiO2-air) atmosphere, respectively. Au nanoparticles were decorated onto the SiNWs/TiO2-Ar samples (SiNWs/TiO2@AuNPs-Ar) to further improve the photoactivity. XRD results showed that the TiO2 shells have an anatase crystalline structure. Photocurrent of solar water splitting was measured by a three electrode setup, in which the Si/TiO2 core/shell nanowire array served as the working electrode. It was found for the first time that Ar ambience annealing is more helpful improving the photocurrent density. The SiNWs/TiO2-Ar sample enhanced the photocurrent by 6.3 times compared to the SiNWs/TiO2-air sample. Furthermore, the SiNWs/TiO2@AuNPs-Ar arrays exhibited a photocurrent of 0.9 mA/cm2, 3.6 times as high as that of its counterpart without Au nanoparticles.

Preparation of birnessite-supported pt nanoparticles and their application in catalytic oxidation of formaldehyde.

Flaky and nanospherical birnessite and birnessite-supported Pt catalysts were successfully prepared and characterized by means of Xray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and N2 adsorption-desorption. Effects of the birnessite morphology and Pt reduction method on the catalytic activity for the complete oxidation of formaldehyde (HCHO) were investigated. It was found that flaky birnessite exhibited higher catalytic activity than nanospherical birnessite. The promoting effect of Pt on the birnessite catalyst indicated that the reduction method of the Pt precursor greatly influenced the catalytic performance. Flaky birnessite-supported Pt nanoparticles reduced by KBH4 showed the highest catalytic activity and could completely oxidize HCHO into CO2 and H20 at 50 degreesC, whereas the sample reduced using H2-plasma showed lower activity for HCHO oxidation. The differences in catalytic activity of these materials were jointly attributed to the effects of pore structure, surface active sites exposed to HCHO and the dispersion of Pt nanoparticles.