食管鳞癌患者唾液菌群的研究

【目的】分析食管鳞癌患者（ESCC组）与健康对照组（HC组）唾液菌群多样性，筛选出食管鳞癌患者唾液中特异性细菌。【方法】收集50例食管鳞癌患者和40例健康对照者的唾液标本，提取总DNA，用PCR扩增16SrDNAV4区，进行高通量测序，将测序数据进行OUT聚类，物种注释及多样性分析。【结果】多样性分析表明ESCC组和HC组整体唾液菌群的多样性及组成方面存在差异（但>0.05），物种分析表明ESCC组以奈瑟菌属（Neisseria）、梭杆菌属（Fusobacterium）、嗜血杆菌属（Haemophilus）、普式菌属（Prevotella）、卟啉单胞菌属（Porphyromonas）为主，健康对照组以奈瑟菌属（Neisseria）、嗜血杆菌属（Haemophilus）、普式菌属（Prevotella）、梭杆菌属（Fusobacterium）、韦荣氏球菌属（Veillonella）为主，LEfSe分析表明ESCC组卟啉菌属表达升高，且具有统计学差异（<0.05）。【结论】食管癌患者唾液有其特征性的菌群组成，与健康对照组相比，食管鳞癌患者唾液中卟啉菌属表达明显升高，是特征性表达的细菌

Simultaneous determination of dissolved anthracene and pyrene in an aqueous solution by synchronous fluorimetry

[中文文摘]利用PAHs具有高的荧光量子产率,同步荧光法具有快速、灵敏、选择性较好的优点,建立了同时测定水溶液中溶解态蒽和芘的方法。所建方法测定蒽和芘的线性范围分别为1.0×10-8~2.0×10-7mol/L和5.0×10-9~3.5×10-7mol/L,检出限分别为1.69×10-9mol/L、8.42×10-10mol/L,相对标准偏差分别为2.90%、2.34%(n=5)。运用所建方法尝试了自来水样品的测定。[英文文摘]A synchronous fluorimetry has been established for simultaneous determination of dissolved anthracene and pyrene in an aqueous solution.The linear ranges for the determination of dissolved anthracene and pyrene were 1.0×10~(-8)～2.0×10~(-7) and 5.0×10~(-9)～3.5×10~(-7) mol/L,their detection limits were 1.69×10~(-9) and 8.42×10~(-10) mol/L,and their relative standard deviations were 2.90% and 2.34%(n=5), respectively.Satisfactory results were obtained by the method for the determination of artificial samples in tap water.国家自然科学基金(20377037); 福建省自然科学基金(D0310006); 厦门大学科技创新项目(2)科学仪器研制与开发(Y07027)资助

Room Temperature Phosphorescence of α-Bromonaphthalene Induced by β-Cyclodextrin in the Presence of Hexahydropyridine

[中文摘要]微量六氢吡啶(HHP)存在下,由于三元包络物α-溴代萘(-αB rN)/β-环糊精(-βCD)/HHP的形成,不经除氧就可观察到强而稳定的室温磷光(RTP)发射。详细研究了温度、pH值以及形成包络物的3种组分物质的浓度的变化对体系RTP的影响。在优化实验条件下,体系的RTP强度与-αB rN的浓度在2.0~20.0μmol/L范围内呈良好线性关系,α-B rN的检出限3.7×10-8mol/L。将所建方法用于合成样品中-αB rN的测定,实验结果表明该方法的加标回收率为92.4%;相对标准偏差小于1.57%(n=7)。[英文摘要]A strong and stable room temperature phosphorescence(RTP) emission was observed from the ternary inclusion complex of α-bromonaphthalene(α-BrN)/β-cyclodextrin(β-CD)/hexahydropyridine(HHP) without deoxygenation from solution in the presence of micro amount of HHP.The effects of temperature,pH values and the variation of concentrations of each component on RTP had been investigated.Under the optimal conditions,the analytical curve of α-BrN gives a liner dynamic range of 2.0-20.0 μmol/L with a detection limit of 3. 7 ×10- 8 mol/L. The experimental results demonstrated that the recovery of the proposed method was 92.4% with a relative standard deviation less than 1. 57% ( n = 7).国家自然科学基金资助项目(No20577037

THE INTERACTION BETWEEN HUMIC ACID AND PYRENE IN THE PRESENCE OF HEAVY METAL IONS

[中文文摘]建立并验证了腐植酸(HA)和芘结合常数(Koc)测定的荧光猝灭法,进而研究了重金属离子对HA和芘相互作用的影响,测定了重金属离子存在下HA和芘之间的Koc.结果表明:纯化后的HA是分子质量较小的部分,水溶性较高,具有羟基、羧基和碳氧键等极性基团;HA利用其分子中的羟基、羧基、碳氧键等基团和重金属离子产生络合作用,这种络合作用影响了HA的结构;随着重金属离子浓度的增大,Koc遵循先增大,再减小,最后趋于不变的趋势.[英文摘要]The fluorescence quenching method for study on the interaction between humic acid(HA) and pyrene was developed and validated.The complexation between HA and Cu~(2+),Fe~(2+)and Ni~(2+)were studied by Infrared spectroscopy.The effects of heavy metal ions on the interaction between HA and pyrene were investigated by the established method.The results showed that the humic acid was the lighter part of the whole molecule and had high aqueous solubility after purified.The binding sites of HA and heavy metal.国家自然科学基金(20577037)资助项

Study on the Interaction Between Humic Acid and Pyrene by Polarity Probe

[中文摘要]芘(Pyrene,Py)的荧光发射光谱的第一振动带和第三振动带强度比值(I1/I3)能够反映其所处微环境的极性,因此运用Py荧光探针法考察了不同化学条件对腐植酸(Humic Acid,HA)假胶束体系微环境性质的影响,以及对HA和Py之间相互作用的影响.结果表明:HA浓度、pH值、盐度、溶剂等化学条件的改变,均会引起Py的I1/I3的变化,因为条件的变化使HA存在形态发生变化,从而导致Py所处为环境极性的变化.另外,重金属离子浓度的变化也可以影响HA和Py之间相互作用的影响,随着重金属离子浓度的增大I1/I3值遵循三段式变化趋势.这些现象均表明HA和PAHs之间的作用以非极性相互作用为主.[英文摘要]In the fluorescence spectra of Pyrene(Py),the ratio of fluorescence emission intensitise corresponding to the first and third peaks(I_1/I_3) was depended on the polarity of the microenvironment where Py located.The effects of the different chemical conditions on the microenvironment of Humic acid(HA) and the interactions between HA and Py were investigated by polarity probe method.The variation of the I_1/I_3 value of Py was studied in the different pH values,as well as in the different concentrations of HA，,sodium chloride and heavy metal ions. The result s showed that the changes of chemical condition resulted in the variations of the I1 / I3 value of Py. Those set s of effect s were explained in terms of conformational adjustment s of HA. Furthermore ,different types of heavy metal ions had different effects on the interactions between HA and the PAHs. To describe the complicated effect s of heavy metal ions ,we use the three2stage variation model that encompasses decreasing and increasing trends and plateaus. The mechanisms were explained in the variation of HA st ructure configuration , HA aggregation and the salting2out effect . All of the results proved that the interactions between HA and Pyrene Py were nonpolar.国家自然科学基金(20577037)资

Room temperature phosphorescence of alpha-bromonaphthalene induced by beta-cyclodextrin in the presence of hexahydropyridine

A strong and stable room temperature phosphorescence (RTP) emission. was observed from: the ternary inclusion complex of alpha-bromonaphthalene (alpha-BrN)/beta-cyclodextrin (beta-CD)/hexahydropyridine (HHP) without deoxygenation from solution in the presence of micro amount of HHP. The effects of temperature, pH values and the variation of concentrations of each component on RTP had been investigated. Under, the optimal conditions, the analytical curve of alpha-BrN gives a liner dynamic range of 2.0 - 20.0 mu mol/L with a detection limit of 3.7 x 10(-8) mol/L. The experimental results demonstrated that the recovery of the proposed method was 92.4% with a relative standard deviation less than 1.57% (n =7)

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel