高效液相色谱-串联质谱法测定化妆品中17种头孢类抗生素

建立了高效液相色谱-串联质谱(HPLC-MS/MS)测定化妆品中的17种头孢类抗生素的方法。化妆品中的头孢类药物使用EDTA-Mcllvaine缓冲液提取,经超声和离心后,上清液经PRIME HLB固相萃取柱净化。采用Waters ACQUITY UPLC BEH C18 (2.1 mm×100 mm,1.7μm)色谱柱分离,流动相为甲醇-0.1%甲酸水溶液,梯度洗脱,电喷雾离子源正离子模式,多反应监测模式(MRM)进行检测。结果表明,17种头孢类药物在此分析方法下分离效果良好,在相应的范围内线性关系良好,相关系数均大于0.99,各加标水平的平均回收率为75.27%~110.32%,相对标准偏差小于10.00%。该方法前处理方便简单,定量准确,适用于化妆品基质中头孢类抗生素的测定。

交联聚乙烯回收料填充高密度聚乙烯的发泡特性

采用机械粉碎法制备得到的交联聚乙烯回收料(RXLPE)填充高密度聚乙烯(HDPE)以提高其熔体强度,并用偶氮二甲酰胺(AC)作为发泡剂在烘箱实现了无压发泡。结果表明,RXLPE加入HDPE后界面相容,部分解交联RXLPE微团分散在HDPE中形成微观"网络"结构,减小了HDPE熔体流动性,但提高了熔体强度和拉伸黏度及"应变硬化"效应。加入发泡助剂氧化锌(ZnO)和硬脂酸锌(ZnSt2)时,AC分解温度从205℃降低到160℃左右,可在低温发泡形成更均匀、粒径更小的泡孔。低于30%含量,增大RXLPE用量可制备发泡率高和强度大的发泡品;RXLPE/HDPE为30∶70时,发泡倍率最高可达6倍多。RXLPE/HDPE同HDPE发泡体受压呈现典型的小变形线弹性、中变形塌陷和大变形密实化的三区行为;适量添加RXLPE和发泡助剂可改善后两区性能;过多RXLPE导致泡孔壁曲折而大变形时响应小。

Medical expenditures for colorectal cancer diagnosis and treatment: A 10-year high-level-hospital-based multicenter retrospective survey in China, 2002-2011

Objective: Colorectal cancer(CRC) causes a substantial burden of disease in China and the evidence of economic burden triggered is fundamental for priority setting. The aim of this survey was to quantify medical expenditures and the time trends for CRC diagnosis and treatment in China.Methods: From 2012 to 2014, a hospital-based multicenter retrospective survey was conducted in 13 provinces across China. For each eligible CRC patient diagnosed from 2002 to 2011, clinical information and expenditure data were extracted using a uniform questionnaire. All expenditure data were reported in Chinese Yuan(CNY)using 2011 values.Results: Of the 14,536 CRC patients included, the average age at diagnosis was 58.2 years and 15.8% were stageI cases. The average medical expenditure per patient was estimated at 37,902 CNY [95 % confidence interval(95%CI): 37,282-38,522], and the annual average increase rate was 9.2% from 2002 to 2011(P for trend <0.001), with a cumulative increase of 2.4 times(from 23,275 CNY to 56,010 CNY). The expenditure per patient in stages Ⅰ, Ⅱ, Ⅲ and Ⅳ were 31,698 CNY, 37,067 CNY, 38,918 CNY and 42,614 CNY, respectively(P<0.001). Expenditure significantly differed within various subgroups. Expenses for drugs contributed the largest proportion(52.6%).Conclusions: These conservative estimates illustrated that medical expenditures for CRC diagnosis and treatment in tertiary hospitals in China were substantial and increased rapidly over the 10 years, with drugs continually being the main expense by 2011. Relatively, medical expenditures are lower for CRC in the earlier stages. These findings will facilitate the economic evaluation of CRC prevention and control in China.

Pharmaceutical cocrystals: A review of preparations, physicochemical properties and applications

Pharmaceutical cocrystals are multicomponent systems in which at least one component is an active pharmaceutical ingredient and the others are pharmaceutically acceptable ingredients.Cocrystallization of a drug substance with a coformer is a promising and emerging approach to improve the performance of pharmaceuticals,such as solubility,dissolution profile,pharmacokinetics and stability.This review article presents a comprehensive overview of pharmaceutical cocrystals,including preparation methods,physicochemical properties,and applications.Furthermore,some examples of drug cocrystals are highlighted to illustrate the effect of crystal structures on the various aspects of active pharmaceutical ingredients,such as physical stability,chemical stability,mechanical properties,optical properties,bioavailability,sustained release and therapeutic effect.This review will provide guidance for more efficient design and manufacture of pharmaceutical cocrystals with desired physicochemical properties and applications.

Soil biofilms:microbial interactions,challenges,and advanced techniques for ex-situ characterization

Soil is inhabited by a myriad of microorganisms,many of which can form supracellular structures,called biofilms,comprised of surface-associated microbial cells embedded in hydrated extracellular polymeric substance that facilitates adhesion and survival.Biofilms enable intensive inter-and intra-species interactions that can increase the degradation efficiency of soil organic matter and materials commonly regarded as toxins.Here,we first discuss organization,dynamics and properties of soil biofilms in the context of traditional approaches to probe the soil microbiome.Social interactions among bacteria,such as cooperation and competition,are discussed.We also summarize different biofilm cultivation devices in combination with optics and fluorescence microscopes as well as sequencing techniques for the study of soil biofilms.Microfluidic platforms,which can be applied to mimic the complex soil environment and study microbial behaviors at the microscale with highthroughput screening and novel measurements,are also highlighted.This review aims to highlight soil biofilm research in order to expand the current limited knowledge about soil microbiomes which until now has mostly ignored biofilms as a dominant growth form.

Review of Geostationary Interferometric Infrared Sounder

To measure the global atmospheric three-dimensional distribution and change of temperature and humidity is one of the key areas in atmospheric remote sensing detection; it is also a new research and development direction in the field of meteorological satellite application. As a main element of China second generation of geostationary meteorological satellite Fengyun 4(FY-4), which was launched on Dec. 11, 2016, the Geostationary Interferometric Infrared Sounder(GIIRS) is the first interferometric infrared sounder working on the international geostationary orbit. It is used for vertical atmospheric sounding and gains atmospheric temperature, humidity, and disturbances. The combination of Fourier transform spectrometer technology and infrared detectors makes GIIRS have high spectral resolution and large coverage over spatial areas. With this kind of instrument, meteorological satellites can improve the capabilities for severe weather event monitoring and numerical weather prediction. Here a concise review of the GIIRS development project, including its history, missions and functions,technical design, key technologies, system integration, calibration and in-orbit operation status, etc., is presented.

Recombinant human erythropoietin accelerated the proliferation of non-small cell lung cancer cell lines and reduced the expression of VEGF,HIF-1α,and PD-L1 under a simulated hypoxic environment in vitro

Background:As erythropoietin(EPO)has been used to treat anemia in cancer patients,negative controversy has continued.Unfortunately,its effects on non-small-cell lung carcinoma(NSCLC)cell lines are uncertain and the phenomenon of inducing immune escape of tumor cells remains to be explored.This study aimed to provide an important basis for the application of exogenous EPO in the treatment of tumor-associated anemia.Methods:Cells were cultured in 1%O2,5%CO_(2),and 94%N2 to simulate a hypoxic environment of the tumor.A549 cell line(lower expression EPOR)and NCI-H838 cell line(higher expression EPOR)were treated with 2 and 8 U/ml recombinant human EPO(rhEPO).CCK-8 method was used to determine the logarithmic growth phase of the cells and to detect cell proliferation.The expression levels of VEGF,HIF-1α,and PD-L1 were determined by western blot.One-way ANOVA was used for statistical analysis between groups,withp<0.05 indicating a significant difference.Results:Hypoxia itself could decrease the survival rate of NSCLC cells.Under the hypoxic condition,rhEPO induced tumor cells proliferation,especially in the NCI-H838 cell line,where 2 U/ml rhEPO increased the total number of surviving cells(Hypoxia+rhEPO 2 U/ml vs.Hypoxia,p<0.05).Western blot analysis showed that hypoxia upregulated the expression of VEGF,HIF-1α,and PD-L1 in NSCLC cell lines(Normoxia vs.Hypoxia,p<0.05),but may not be dependent on the expression levels of EPOR.RhEPO decreased the expression levels of VEGF and HIF-1α.In the A549 cell line,it depended on the concentration of rhEPO and was particularly obvious in HIF-1α(Hypoxia vs.Hypoxia+rhEPO 2 U/ml vs.Hypoxia+rhEPO 8 U/ml,p<0.05).A low concentration of rhEPO may not reduce VEGF expression.In the NCI-H838 cell line,the effect of rhEPO on VEGF was more obvious,but it may be independent of rhEPO concentrations.The downregulation of PD-L1 expression by rhEPO was only presented in the A549 cell line and required higher rhEPO concentrations(Hypoxia+rhEPO 8 U/ml vs.Hypoxia&Hypoxia+rhEPO 2 U/ml,p<0.05).Conclusion:The effect of prolonged high concentrations of rhEPO under hypoxic conditions resulted in accelerated cells proliferation of non-small-cell lung cancer and was independent of EPOR expression levels on the cell lines surface.Hypoxia resulted in increased expression of VEGF,HIF-1α,and PD-L1 on the NSCLC cell lines.Under normoxic conditions,rhEPO did not affect the expression of VEGF,HIF-1α,and PD-L1;but under hypoxic conditions,the application of rhEPO reduced the expression of VEGF,HIF-1α,and PD-L1,producing an impact on the biological behavior of tumor cells.

Characteristics of night soil and leaf co-composting using aerobic static method

这个工作的主要目的是用氧气的静态的 composting 方法调查夜里土壤和叶堆肥 co 的特征。三影响因素，夜里土壤和叶的包括的比例，通风率和通风模式，通过主要物理化学的性质的进化被调查，即，温度，氧消费率，有机物，潮湿内容，碳，氮， carbon-to-nitrogen 比率和萌芽索引(官方补给) 。夜里土壤和叶的 3:1 (w:w ) 混合能够完成最高的 composting 温度，这被发现。

Zooming in to acquire micro-reaction:Application of microfluidics on soil microbiome

Microfluidics confers unique advantages in microbiological studies as these devices can accurately replicate the micro-and even nano-scale structures of soil to simulate the habitats of bacteria.It not only helps us understand the spatial distribution of bacterial communities(such as biofilms),but also provides mechanistic insights into microbial behaviors including chemotaxis and horizontal gene transfer(HGT).Microfluidics provides a feasible means for real-time,in situ studies and enables indepth exploration of the mechanisms of interactions in the soil microbiome.This review aims to introduce the basic principles of microfluidic technology and summarize the recent progress in microfluidic devices to study bacterial spatial distribution and functions,as well as biological processes,such bacterial chemotaxis,biofilm streamers(BS),quorum sensing(QS),and HGT.The challenges in and future development of microfluidics for soil microbiological studies are also discussed.