Molecular Dynamics Simulation Study on the Interactions of Mixed Cationic/Anionic Collectors on Muscovite (001) Surface in Aqueous Solution

In this study, the adsorption mechanisms of dodecylamine hydrochloride(DDAHC), sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate(SDBS), and their mixed anionic/cationic collectors at ten different molar ratios on a muscovite (Mcv) surface in neutral aqueous solution were assessed by molecular dynamics simulations (MDS). According to the snapshot, interaction energy, radial distribution function (RDF), and density profile between the Mcv surface and collector molecules, the individual DDAHC collector was an effective collector for the flotation of Mcv. The molar ratio of anionic/cationic collectors was determined to be an essential factor in the flotation recovery of Mcv. The DDAHC collector was involved in the adsorption of the mixed anionic/cationic collectors on the Mcv (001) surface, whereas SDS and SDBS collectors were co-adsorbed with DDAHC. The mixed cationic/anionic collector showed the best adsorption on the Mcv surface in a molar ratio of 2. Additionally, SDBS, which has one more benzene ring than SDS, was more likely to form spherical micelles with DDAHC, thus resulting in better adsorption on the Mcv surface. The results of micro-flotation experiments indicated that the DDAHC collector could improve the flotation recovery of Mcv in neutral aqueous solution, which was in agreement with MDS-derived findings. In conclusion, DDAHC alone is the optimum collector for Mcv flotation under the neutral aqueous conditions, while the mixture of DDAHC and SDBS collectors (molar ratio = 2:1) exhibits the similar flotation performance.     

赴泰国旅客旅行健康知识及行为调查分析

目的了解石家庄机场赴泰国旅客对当地高发传染病的认知现状和个人防护能力情况,为制定高风险航线往来旅客的风险分析方案提供依据。方法采取随机抽样方法,对由石家庄机场赴泰国游的旅客在知情同意的情况下进行面对面的问卷调查,所有资料录入Excel后采用SPSS 13.0软件进行统计分析。结果回收的503份有效调查问卷中,本科学历、收入中等偏上、第一次出境旅游的中青年人群为主体,具有目前出境游人群的代表性;有效问卷中,65.8%的人选择通过旅行社了解赴泰国旅行注意事项;大多数旅客集中选择泰国是"登革热"(42.5%)和"疟疾"(25.2%)的流行区域,而选择"痢疾"和"霍乱"的只占14.1%和11.9%;58.1%的旅客出境前未接种过任何疫苗;23.7%旅客不知道应该到哪里进行旅行前的健康咨询,13.1%不清楚归国后如有发热、皮疹等传染病症状该如何就医。结论评价口岸传染病防控能力现状,逐步构建主动型卫生检疫查验系统;完善风险评估机制,有针对性地对重点航班和人群采取多举措宣教以提升防病意识;应多部门联合持续加强出入境人员的传染病宣教、监测和防控工作。     

The Biomarkers for Predicting Viral Hepatitis-Associated Hepatocellular Carcinoma

BackgroundHepatocellular carcinoma (HCC) is the fifth most common cancer in the world, and more than half of the newly diagnosed cases are chronic hepatitis B patients. Due to the lack of specific clinical manifestations, many patients are already at an advanced stage at the time of diagnosis and therefore have missed the best time for treatment. Organs in a pathological state usually secrete specific substances into the blood, which can indirectly indicate the pathological state of the organ, so some biological markers in the blood can be used as a tool to predict the incidence of HCC.MethodsThe Research articles related to HCC were collected by searching PubMed databases with the keywords “hepatocellular carcinoma”, “serum biomarker”, “hepatitis B”, “prediction” and “prognosis”, and Additional articles were identified by manual search of references found in the primary articles, followed by a summary and review.ResultsViral hepatitis is the main cause of HCC worldwide, and this phenomenon is particularly prominent in Asian and African populations. A variety of serological markers including M2BPGi, IL-6 and COMP can be used to predict the incidence of long-term HCC in patients. The risk of HCC is dynamic rather than constant, and dynamic detection will help improve prediction accuracy. For hepatitis B patients, HBV DNA load and HBcr Ag are important predictive markers of HCC.ConclusionFor a high-risk population of HCC, early risk prediction is helpful to guide clinical work, and timely adjustments of the screening frequency and treatment plan are helpful to prolong the survival time of HCC patients.     

Lipopolysaccharide mouse models for Parkinson’s disease research: a critical appraisal

Parkinson’s disease, the most common movement disorder, has a strong neuroinflammatory aspect. This is evident by increased pro-inflammatory cytokines in the serum, and the presence of activated microglial cells, and inflammatory cytokines in the substantia nigra of post-mortem brains as well as cerebrospinal fluid of Parkinson’s disease patients. The central and peripheral neuroinflammatory aspects of Parkinson’s disease can be investigated in vivo via administration of the inflammagen lipopolysaccharide, a component of the cell wall of gram-negative bacteria. In this mini-review, we will critically evaluate different routes of lipopolysaccharide administration (including intranasal systemic and stereotasic), their relevance to clinical Parkinson’s disease as well as the recent findings in lipopolysaccharide mouse models. We will also share our own experiences with systemic and intrastriatal lipopolysaccharide models in C57BL/6 mice and will discuss the usefulness of lipopolysaccharide mouse models for future research in the field.Key Words: C57BL/6 mice, intranasal models, lipopolysaccharide models, neuroinflammation, Parkinson’s disease, stereotaxic models, substantia nigra, systemic models     

广州医疗服务满意度现况初步调查

目的 了解广州市民对医疗服务的满意情况。方法 用调查问卷的方式在广州市调查642人。结果 69.2%的人对总的医疗服务质量满意，大部分人认为医生的医术水平是可以依赖的，选择小医院就诊的比例较高。“红包”现象和医疗纠纷依然存在。结论 文化程度和等候时间是医疗服务满意度的影响因素。     

Antigenic Evolution Characteristics and Immunological Evaluation of H9N2 Avian Influenza Viruses from 1994–2019 in China

The H9N2 subtype avian influenza viruses (AIVs) have been circulating in China for more than 20 years, attracting more and more attention due to the potential threat of them. At present, vaccination is a common prevention and control strategy in poultry farms, but as virus antigenicity evolves, the immune protection efficiency of vaccines has constantly been challenged. In this study, we downloaded the hemagglutinin (HA) protein sequences of the H9N2 subtype AIVs from 1994 to 2019 in China—with a total of 5138 sequences. The above sequences were analyzed in terms of time and space, and it was found that h9.4.2.5 was the most popular in various regions of China. Furthermore, the prevalence of H9N2 subtype AIVs in China around 2006 was different. The domestic epidemic branch was relatively diversified from 1994 to 2006. After 2006, the epidemic branch each year was h9.4.2.5. We compared the sequences around 2006 as a whole and screened out 15 different amino acid positions. Based on the HA protein of A/chicken/Guangxi/55/2005 (GX55), the abovementioned amino acid mutations were completed. According to the 12-plasmid reverse genetic system, the rescue of the mutant virus was completed using A/PuertoRico/8/1934 (H1N1) (PR8) as the backbone. The cross hemagglutination inhibition test showed that these mutant sites could transform the parental strain from the old to the new antigenic region. Animal experiments indicated that the mutant virus provided significant protection against the virus from the new antigenic region. This study revealed the antigenic evolution of H9N2 subtype AIVs in China. At the same time, it provided an experimental basis for the development of new vaccines.     

A Novel Herbal Extract Blend Product Prevents Particulate Matters-Induced Inflammation by Improving Gut Microbiota and Maintaining the Integrity of the Intestinal Barrier

Air pollutants of PM2.5 can alter the composition of gut microbiota and lead to inflammation in the lung and gastrointestinal tract. The aim of this study was to evaluate the protective effect of a novel herbal extract blend, FC, composed of Lonicera japonica extract, Momordica grosvenori extract, and broccoli seed extract, on PM2.5-induced inflammation in the respiratory and intestinal tract. A549 cells and THP-1 cells, as well as C57BL/6 mice, were stimulated with PM2.5 to establish in vitro and in vivo exposure models. The models were treated with or without FC. The expression of inflammatory cytokines and tight junction proteins were studied. Proteomic analysis was performed to elucidate mechanisms. Mouse feces were collected for gut microbiota analysis. FC was shown to modulate the upregulation of pro-inflammatory cytokines mRNA expression in A549 and THP-1 cells and downregulated tight junction proteins mRNA expression in A549 cells due to PM2.5 stimulation. In animal models, the decreased expression of the anti-inflammatory factor il-10, tight junction protein ZO-1, and the elevated expression of COX-2 induced by PM2.5 were improved by FC intervention, which may be associated with zo-1 and cox-2 signaling pathways. In addition, FC was shown to improve the gut microbiota by increasing the abundance of beneficial bacteria.     

Molecular Analysis of Caprine Enterovirus Circulating in China during 2016–2021: Evolutionary Significance

Here, we report the characterization of 13 novel caprine/ovine enterovirus strains isolated from different regions in China during 2016–2021. Immunoperoxidase monolayer assay showed that these viral strains shared strong cross-reaction with the previously reported caprine enterovirus CEV-JL14. Alignment analysis of the complete nucleotide sequences revealed 79.2%–87.8% and 75.0%–76.7% sequence identity of these novel caprine enterovirus strains to CEV-JL14 and TB4-OEV, respectively. Phylogenetic analyses clustered these novel strains to EV-G based on the amino acid sequences of P1 and 2C+3CD. Moreover, phylogenetic analysis of these caprine enterovirus strains identified three new EV-G types using VP1 sequences. These results demonstrate the genetic variations and the evolution of caprine enterovirus.     

Microstructure of Dolostones of Different Geological Ages and Dedolomitization Reaction

Dolostone is widely distributed and commonly used as concrete aggregates. A large number of studies have shown that there are significant differences in the expansibility of different dolostones, and the key factors determining the expansibility of alkali carbonate rocks have not been clarified. In this paper, rocks were selected from five different geological ages: Jixianian, Cambrian, Ordovician, Devonian, and Triassic ages. The ordering degree and the content of MgCO₃ of dolomites in rocks of different geological ages were determined by X-ray diffraction (XRD). The degree of dedolomitization reaction in rocks cured in 80 °C, 1 mol/L NaOH solution was determined by quantitative X-ray diffraction (QXRD). The morphology of dolomites in rocks was determined by a polarizing microscope. The products of the dedolomitization reaction were determined by field emission electron microscopy (FESEM-EDS). According to the test results, the following conclusions are drawn. There is a good positive correlation between ordering degree and the molar fraction of MgCO₃ of dolomites. When the MgCO₃ mole fraction of dolomites varies from 47.17% to 49.60%, the higher the MgCO₃ mole fraction, the greater the ordering degree of dolomite. By analyzing the degree of the dedolomitization reaction of different dolostone powders cured at 80 °C in 1 mol/L NaOH solution, it is found that the older the geological age of dolostone, the slower the dedolomitization reaction rate and the lower the degree of dedolomitization reaction. The lower the ordering degree of dolomite crystal in the same geological age, the faster the rate of dedolomitization reaction and the higher the degree of dedolomitization reaction.