杭州稻麦菜轮作地区大气氮湿沉降

通过雨水中NH+4-N/NO-3-N比率和铵态氮自然丰度值(δ15NH+4)的变化探讨大气氮湿沉降与农作施肥活动的关联性. 2003年6月至2005年7月,采用自行设计定制的雨水收集器在浙江杭州稻-麦-蔬菜轮作地区进行了为期2a的全天候连续雨水采样分析.结果显示,杭州稻-麦-蔬菜轮作地区雨水中NH+4-N/NO-3-N比率和δ15NH+4值呈现相似的季节性变化,雨水中NH+4-N/NO-3-N的峰值出现在6月底～9月上旬,而后逐渐下降,秋冬季(10～11月份)降到最低;来春麦菜集中施肥期(2～3月份),又呈现多个小高峰;5～6月份为单季稻和蔬菜基肥和追肥集中施用期,故而峰值也达4以上;入冬后仅在麦田施肥期出现一个小高峰而后明显下降,大都降到1以下;频繁施肥期雨水中的NH+4-N/NO-3-N比率值是农闲期的2～4倍,显示雨水NH+4-N/NO-3-N比率与农田施肥活动有密切关联与同步性,但与气温无直接关联(R2=0.0129).雨水中δ15NH+4值的变化,与雨水中NH+4-N/NO-3-N比率相似,呈现明显的季节性变化:稻麦生育后期与种前空闲期为正值,麦稻蔬菜集中施肥期转为负值.雨水中NH+4-N/NO-3-N比率与δ15NH+4值对大气湿沉降中氮的来源、形态及地面NH3排放源的强度有一定的表征意义.     

五苓胶囊对前列腺癌循环miRNA-141表达的影响

目的:采用荧光定量PCR法检测前列腺癌循环miRNA-141表达,并研究五苓胶囊对其影响。方法:选取我院泌尿外科收治的前列腺癌患者20例,随机分为A、B两组,各10例;A组给予常规治疗,B组在常规治疗基础上给予加用五苓胶囊治疗。选取同期住院前列腺增生患者20例,正常对照组为同时期体检健康者20例。采用荧光定量PCR法检测正常对照组、前列腺增生组以及前列腺癌组血清miRNA-141的表达情况,以及前列腺癌组治疗前TPSA(前列腺特异性抗原)含量。结果:前列腺癌组的血清miRNA-141的表达水平为正常对照组的(11.22±8.19)倍,明显高于前列腺增生组(1.65±1.73)和正常对照组,差异有统计学意义(P0.05);前列腺增生组和正常对照组比较无明显差异(P0.05);前列腺癌组血清miRNA-141的表达水平与TPSA水平呈正相关关系,相关系数r=0.753,有统计学意义(P0.05)。治疗后,前列腺癌A组与B组的血清miRNA-141的表达水平均有所改善,与A组(5.82±4.51)相比较,B组的miRNA-141的表达水平(1.93±0.67)明显降低,差异有统计学意义(P0.05)。结论:前列腺癌患者血清中miRNA-141表达水平明显升高,且与TPSA水平呈正相关关系,五苓胶囊能够降低miRNA-141表达。     

Comparison of luminescence property of gamma‐ray irradiated Tb3+‐doped and Ce3+ co‐doped potassium halide single crystals

Single crystals of KCl and KBr singly and doubly doped with Tb³⁺ and Ce³⁺, respectively, were successfully grown using the Bridgeman technique. This work reports the comparative luminescence behavior and optical absorption characterization of non‐irradiated and γ‐ray‐irradiated single crystals of these materials. The existing defect and the defect created by γ‐ray irradiation were monitored by optical absorption spectra. The excitation and emission spectra of these materials were measured at room temperature with a spectrofluorometer and the pertaining results were compared. The F‐band comparison was made when bleached with F‐light for 2 mins. The trap‐level changes in KCl and KBr when it is singly and doubly doped enabled us to draw conclusions on the nature of the defect and on the recombination processes involved.     

Microcalorimetric study of the action of Ce(III) ions on the growth of E. coli

A microcalorimetric technique based on bacterial heat output was used to evaluate the action of Ce(III) ions on the growth of Escherichia coli. The power-time curves of the growth metabolism of the bacteria were studied in the presence and absence of Ce(III) by means of a LKB-2277 Bioactivity Monitor, by a stopped-flow method at 37°C. For evaluation of the results, the maximum power, P _max, the growth rate constant k, and the heat effects Q _log, Q _stat, and Q _tot for the log phase, the stationary phase, and total heat output, respectively, were determined. For comparison, a spectrophotometer was used to estimate the number of cells in the liquid culture. The shape of the bacteria was examined by electron microscopy. We concluded that the presence of cerium ions at concentrations below 350 μg/mL have a stimulatory effect on the growth of E. coli, whereas concentrations at or above 400 μg/mL may have an inhibitory effect.     

Optical and structural properties of composites films based on Ce3+-doped yttrium aluminium garnet nanoparticles embedded in polystyrene

In the present work, attempts have been made to prepare scintillating nanoparticle composite films of Ce³⁺-doped Y₃Al₅O₁₂ (YAG:Ce) embedded in a polystyrene (PS) polymer. A YAG:Ce phosphor has been previously synthesized using the sol–gel method. YAG:Ce-PS composite films of 250 ± 30 μm thickness were prepared using a solvent casting procedure with different PS/solvent concentration and a different mass ratio between nanoparticles of YAG:Ce and PS. X-ray diffraction analysis confirmed that the YAG:Ce powders were successfully prepared. Using thermogravimetric analyses and differential scanning calorimetry, we found that the glass transition temperature (Tg) and thermal degradation were shifted to higher temperatures for composite films relative to pure PS. Photoluminescence showed the yellow emission of the Ce³⁺-doped YAG phosphors, which was attributed to the 5d→4f transition of Ce³⁺ ion and the intensity of the emissions changed with the mass ratio of the YAG:Ce nanoparticles incorporated in the polymer and with the concentration of the polymer solution.     

LncRNA MEG3 inhibits rheumatoid arthritis through miR‐141 and inactivation of AKT/mTOR signalling pathway

Rheumatoid arthritis (RA) is a chronic inflammation mediated by autoimmune responses. MEG3, a kind of long noncoding RNA (lncRNA), participates in cell proliferation in cancer tissues. However, the correlation between MEG3 and RA is yet unclear. Therefore, to clarify how MEG3 works in RA, we performed a series of experiments using RA samples. We found that MEG3 was downregulated in the fibroblast‐like synoviocytes of RA patients (RA‐FLS), in comparison with healthy subjects. MEG3 was also down‐regulated evidently in lipopolysaccharide (LPS)‐treated chondrocyte. As part of our experiments, MEG3 was overexpressed in chondrocyte by transfection with lentivirus containing sequences encoding MEG3. In addition, in presence of LPS, reductions were identified not only in the cell proliferation, but also in the generation of interleukin‐23 (IL‐23), which, however were reversed in the lentivirus (containing MEG3‐encoding sequences)‐transfected chondrocytes. Up‐regulated MEG3 resulted in an increase the level of Ki67. Moreover, MEG3 was negatively correlated with miR‐141, and miR‐141 was up‐regulated in LPS‐treated chondrocyte. Inhibitory effects of MEG3 overexpression, mentioned above, were partially abolished by overexpressed miR‐141. Further, animal experiment also showed the inhibitory effect of MEG3 in overexpression on the AKT/mTOR signaling pathway. In‐vivoexperiments also showed that cell proliferation was facilitated by MEG3 overexpression with inhibited inflammation. In summary, the protective role of MEG3 in RA was proved to be exerted by the increase in the rate of proliferation, which might correlate to the regulatory role of miR‐141 and AKT/mTOR signal pathway, suggesting that MEG3 holds great promise as a therapeutic strategy for RA.     

非小细胞肺癌患者血清miR-146a、miR-141的表达及临床意义

目的:研究非小细胞肺癌(NSCLC)患者血清微小RNA-146a(mi R-146a)、mi R-141的表达及临床意义。方法:选取2015年1月至2018年1月我院收治的106例NSCLC患者记为NSCLC组,另选取同期于我院进行体检的40例健康体检者记为健康对照组。采用荧光实时定量PCR(qRT-PCR)检测两组血清mi R-146a、mi R-141的表达水平,分析NSCLC患者血清mi R-146a、mi R-141表达水平与临床病理参数的关系,比较血清mi R-146a、mi R-141单一诊断及联合诊断NSCLC的曲线下面积(AUC)、灵敏度、特异度。结果:NSCLC组患者的血清mi R-146a、mi R-141表达水平高于健康对照组(P0.05)。NSCLC患者血清mi R-146a表达水平与病理分期有关(P0.05),与年龄、性别、吸烟史、病理类型、病理分级、肿瘤直径及是否伴有淋巴结转移无关(P0.05)。NSCLC患者血清mi R-141表达水平与病理分期、病理分级及是否伴有淋巴结转移有关(P0.05),与年龄、性别、吸烟史、病理类型、肿瘤直径无关(P0.05)。血清mi R-146a、mi R-141单一诊断及两者联合诊断NSCLC的AUC分别为0.841、0.772、0.921,敏感度分别为85.1%、80.5%、93.5%,特异度分别为84.2%、75.3%、89.8%。结论:NSCLC患者血清mi R-146a、mi R-141表达水平升高,且与部分临床病理参数有关,两者联合检测对NSCLC诊断具有较高的诊断价值。     

Luminescence and energy transfer in Ce3+, Mn2+‐doped K2AEP2O7 (AE = Ca,Sr) phosphor

Pyrophosphates K₂AEP₂O₇ (AE = Ca, Sr) prepared by the classical solid‐state technique and activated with Ce³⁺ are described. Intense emission was observed in K₂AEP₂O₇ (AE = Ca, Sr). The effect of Mn²⁺ co‐doping was studied. The broad emission peak of Mn²⁺ was observed at 534 nm in K₂SrP₂O₇:Ce³⁺ and at 539 nm in K₂CaP₂O₇:Ce³⁺, Mn²⁺. Mn²⁺ emission was greatly enhanced by addition of the sensitizer Ce³⁺ due to efficient energy transfer from Ce³⁺ to Mn²⁺. Copyright © 2015 John Wiley & Sons, Ltd.