Clinical observation of Shenmai injection in the treatment for adverse reactions of chemotherapy on advanced non-small cell lung cancer

Objective: To observe the efficacy of Shenmai injection in the treatment for adverse reactions of chemotherapy on advanced non-small cell lung cancer (NSCLC). Methods: 45 NSCLC patients with stages IIIb-IV were randomly divided into two groups: the treatment group (treated by chemotherapy combined with Shenmai injection) and the control group (treated by chemotherapy only). The efficacy of the two groups was evaluated after 3 cycles of treatment. Results: There was no significant difference between the two groups in the recent curative effects (P > 0.05), while there were significant differences between them in Karnofsky score and weight (P < 0.05). The treatment group was better than the control group in preventing leucopenia and decreased hemoglobin, and significant differences were found between them (P < 0.05). The incidence of thrombocytopenia, nausea and vomiting, hepatic and renal dysfunction in the treatment group was lower than that in the control group, but no significant differences were found between them (P > 0.05). Conclusion: Shenmai injection would not influence the efficacy of chemotherapy on advanced NSCLC patients, while it could improve the quality of life, increase the body weight of patients, alleviate adverse reactions of chemotherapy as myelosuppression so as to improve the tolerance of organism to chemotherapy.

Oxidation-strengthened disulfide-bridged prodrug nanoplatforms with cascade facilitated drug release for synergetic photochemotherapy

One of the major barriers in utilizing prodrug nanocarriers for cancer therapy is the slow release of parent drug in tumors.Tumor cells generally display the higher oxidative level than normal cells,and also displayed the heterogeneity in terms of redox homeostasis level.We previously found that the disulfide bond-linkage demonstrates surprising oxidationsensitivity to form the hydrophilic sulfoxide and sulphone groups.Herein,we develop oxidation-strengthened prodrug nanosystem loaded with pyropheophorbide a(PPa)to achieve light-activatable cascade drug release and enhance therapeutic efficacy.The disulfide bond-driven prodrug nanosystems not only respond to the redox-heterogeneity in tumor,but also respond to the exogenous oxidant(singlet oxygen)elicited by photosensitizers.Once the prodrug nanoparticles(NPs)are activated under irradiation,they would undergo an oxidative self-strengthened process,resulting in a facilitated drug cascade release.The IC50 value of the PPa@PTX-S-S NPs without irradiation was 2-fold higher than those of NPs plus irradiation.In vivo,the PPa@PTX prodrug NPs display prolonged systemic circulation and increased accumulation in tumor site.The PPa@PTXS-S NPs showed much higher efficiency than free PTX or the PPa@PTX-C-C NPs to suppress the growth of 4 T1 tumors.Therefore,this novel oxidation-strengthened disulfide-bridged prodrug-nanosystem has a great potential in the enhanced efficacy of cancer synergetic photochemotherapy.

钛精矿碳热硫化制备含硫MAX相Ti_(2)SC

含硫MAX相Ti_(2)SC被认为是很有潜力的高温结构材料及熔盐电解提钛前驱体。但现有制备方法均涉及高值Ti粉、TiC粉及TiS粉的使用,难以实现其规模化应用。本工作以钛精矿为钛源,黄铁矿为硫源,石墨球形尾料为碳源,探索了碳热硫化钛精矿低成本制备高纯Ti_(2)SC的可行性。研究了FeTiO_(3)/FeS_(2)/C体系中Ti_(2)SC的形成机理;石墨添加量、烧结温度与烧结时间对产物纯度与形貌的影响规律;高温原位物理分离副产物Fe对提纯过程酸用量减少的实际占比。结果表明,Ti_(2)SC生成的关键反应是FeTiO_(3)碳热还原中间产物Ti_(3)O_(5)在熔融FeS中直接脱氧重构为Ti_(2)SC;石墨添加量27.4wt%的试样经1400℃下烧结4 h及后续酸洗处理,可以得到纯度大于96wt%的Ti_(2)SC;1700℃下的高温烧结可以实现部分副产物Fe与Ti_(2)SC的分离,酸洗提纯过程酸用量减少72.7%。该方法有望实现高纯Ti_(2)SC的规模化制备。

Significant effects of transport on nanoparticles during new particle formation events in the atmosphere of Beijing

The mechanisms of new particle formation(NPF)events that occurred under high aerosol loadings(“polluted”NPF)in the atmosphere have been unclear,which has inhibited the precision of particlepollution control.To deepen the understanding of how the“polluted”NPF events occur,a one-monthcomprehensive measurement was conducted in the atmosphere of Beijing during the summer of2016.The“clean”NPF events(frequency=22%)(condensation sink,CS<0.015 s^(-1))were found to becaused by local nucleation and growth.The“polluted”NPF events(frequency=28%)(CS>0.015 s^(-1))were influenced by both local nucleation-growth and regional transport,and the contributions from thetwo factors to 6e25 nm particle number concentration were 60%and 40%,respectively.This studyemphasized the importance of the transport for nanoparticles in relatively polluted atmospheres,and forthat the regional joint particle pollution control would be an essential policy.

Explicit diagnosis of the local ozone production rate and the ozone-NOx-VOC sensitivities

In the troposphere, ozone is a harmful gas compound to both human health and vegetation. Ozone is produced from the reaction of NO_x(@NO + NO_2) and VOCs(volatile organic compounds) with light. Due to the highly nonlinear relationships between ozone and its precursors, proper ozone mitigation relies on the knowledge of chemical mechanisms. In this study, an observation-based method is used to simulate ozone formation and elucidate its controlling factors for a rural site on the North China Plain. The instantaneous ozone production rate is calculated utilizing a box model using the dataset obtained from the Wangdu campaign. First, the model was operated in a time-dependent mode to calculate the ozone production rate at each time stamp. The calculated ozone formation rate showed a diurnal average maximum value of 17 ppbv/h(1-h diurnal averaged). The contribution of individual peroxy radicals to ozone production was analyzed. In addition, the functional dependence of calculated P(O_3) reveals that ozone production was in a NO_x-limited regime during the campaign. Furthermore, the missing peroxy radical source will further extend NO_x-limited conditions to earlier in the day, making NO_xlimitation dominate more of a day than the current chemical model predicts. Finally, a multiple scenarios mode,also known as EKMA(empirical kinetic modeling approach), was used to simulate the response of P(O_3) to the imaginary change in precursor concentrations. We found that ozone production was in the NO_x-limited region. However, the use of NO_2 measured by the molybdenum converter and/or the absence of a peroxy radical source in the current chemical model could over-emphasize the VOC-limited effect on ozone production.

Characteristics and formation mechanism of regional haze episodes in the Pearl River Delta of China

To investigate the characteristics and the specific mechanism of continuous haze,comprehensive measurements were conducted from 15 October to 19 November in the Atmospheric Environment Monitoring Super-Station in Heshan of Guangdong province.Five haze episodes occurred in October and November 2014 in the Pearl River Delta（PRD）region. The meteorological parameters, gas data, chemical compositions, and optical parameters of the aerosols were obtained. Among these events, the second haze episode,with the highest concentration of PM2.5 of 187.51 μg/m^3, was the most severe. NO^3-was always higher than SO_4^（2-）, which indicated that motor vehicles played an important role in the haze, even though the oxidation rate from SO_2 to SO_4^（2-）was faster than that of NOXto NO_3^-. The difference between the hourly averages of Na＋and K＋during the haze episode and clean days was small, implying that straw combustion and sea salt had no significant effect on the occurrence of haze, and the backward trajectories of the air masses also conformed with this result. The air pollutants were difficult to disperse because of the significant decrease in the planetary boundary layer（PBL） height. Relative humidity played a crucial role in the formation of haze by leading to hygroscopic growth of the diameter of aerosols.

Size-resolved effective density of submicron particles during summertime in the rural atmosphere of Beijing, China

Particle density is an important physical property of atmospheric particles. The information on high time-resolution size-resolved particle density is essential for understanding the atmospheric physical and chemical aging processes of aerosols particles. In the present study, a centrifugal particle mass analyzer （CPMA） combined with a differential mobility analyzer （DMA） was deployed to determine the size-resolved effective density of 50 to 350 nm particles at a rural site of Beijing during summer 2016. The measured particle effective densities decreased with increasing particle sizes and ranged from 1.43 to 1.55 g/cm3, on average. The effective particle density distributions were dominated by a mode peaked at around 1.5 g/cm3 for 50 to 350 nm particles. Extra modes with peaks at 1.0, 0.8, and 0.6 g/cm3 for 150, 240, and 350 nm particles, which might be freshly emitted soot particles, were observed during intensive primary emissions episodes. The particle effective densities showed a diurnal variation pattern, with higher values during daytime. A case study showed that the effective density of Aitken mode particles during the new particle formation （NPF） event decreased considerably, indicating the significant contribution of organics to new particle growth.

Wintertime N2O5 uptake coefficients over the North China Plain

The heterogeneous hydrolysis of dinitrogen pentoxide(N2O5)plays an important role in regulating NOx.The N2O5 uptake coefficient,γ(N2O5),was determined using an iterative box model that was constrained to observational data obtained in suburban Beijing from February to March 2016.The box model determined 2289 individualγ(N2O5)values that varied from<0.001 to 0.02 with an average value of 0.0046±0.0039(and a median value of 0.0032).We found the derived winterγ(N2O5)values in Beijing were relatively low as compared to values reported in previous field studies conducted during winter in Hong Kong(average value of 0.014)and the eastern U.S.coast(median value of 0.0143).In our study,field evidence of the suppression ofγ(N2O5)values due to pNO3-content,organics and the enhancement by aerosol liquid water content(ALWC)is in line with previous laboratory study results.Low ALWC,high pNO3-content,and particle morphology(inorganic core with an organic shell)accounted for the lowγ(N2O5)values in the North China Plain(NCP)during wintertime.The field-derivedγ(N2O5)values are well reproduced by a revised parameterization method,which includes the aerosol size distribution,ALWC,nitrate and organic coating,suggesting the feasibility of comprehensive parameterization in the NCP during wintertime.

In situ monitoring of atmospheric nitrous acid based on multi-pumping flow system and liquid waveguide capillary cell

In the last four decades, various techniques including spectroscopic, wet chemical and mass spectrometric methods, have been developed and applied for the detection of ambient nitrous acid（HONO）. We developed a HONO detection system based on long path photometry which consists of three independent modules i.e., sampling module, fluid propulsion module and detection module. In the propulsion module, solenoid pumps are applied. With solenoid pumps the pulsed flow can be computer controlled both in terms of pump stroke volume and pulse frequency, which enables the attainment of a very stable flow rate. In the detection module, a customized Liquid Waveguide Capillary Cell（LWCC） is used. The customized LWCC pre-sets the optical fiber in-coupling with the liquid wave guide, providing the option of fast startup and easy maintenance of the absorption photometry. In summer 2014, our system was deployed in a comprehensive campaign at a rural site in the North China Plain. More than one month of high quality HONO data spanning from the limit of detection to 5 ppb were collected. Intercomparison of our system with another established system from Forschungszentrum Juelich is presented and discussed. In conclusion, our instrument achieved a detection limit of 10 ppt V within2 min and a measurement uncertainty of 7%, which is well suited for investigation of the HONO budget from urban to rural conditions in China.

Designing anticancer combretastatin A-4 analogues with aggregation-induced emission characteristics

Herein a series of combretastatin A-4(CA-4)analogues with aggregation-induced emission characteristics(compounds a1-a19)were rationally designed and synthesized.The research results showed that the mechanism of AIE of a1-a19 could be attributed to the dual function of the restriction of intramolecular motion(RIM)and J-aggregate formation.Furthermore,the detailed investigation on the action mechanisms revealed that a19 diffused from lysosomes into the cytoplasm,and then targeted the colchicine binding site to induce cell cycle arrest and apoptosis in cancer cells.These results provide new ideas and impetus for the rational design of CA-4 analogues.

Ambient photolysis frequency of NO2 determined using chemical actinometer and spectroradiometer at an urban site in Beijing

The photolysis frequency of NO2, j（NO2）, is an important analytical parameter in the study of tropospheric chemistry. A chemical actinometer （CA） was built to measure the ambient j（NQ） based on a high precision NOx instrument with 1 min time resolution. Parallel measurements of the ambient j（NO2） by using the CA and a commercial spectroradiometer （SR） were conducted at a typical urban site （Peking University Urban Environmental Monitoring Station） in Beijing. In general, good agreement was achieved between the CA and SR data with a high linear correlation coefficient （R2 = 0.977） and a regression slope of 1.12. The regression offset was negligible compared to the measured signal level. Thej（NO2） data were calculated using the tropospheric ultraviolet visible radiation （TUV） model, which was constrained to observe aerosol optical properties. The calculated j（NO2） was intermediate between the results obtained with CA and SR, demonstrating the consistency of all the parameters observed at this site. The good agreement between the CA and SR data, and the consistency with the TUV model results, demonstrate the good performance of the installed SR instrument. Since a drift of the SR sensitivity is expected by the manufacturer, we propose a regular check of the data acquired via SR against those obtained by CA for long-term delivery of a high quality series ofj（NO2） data. Establishing such a time series will be invaluable for analyzing the long-term atmospheric oxidation capacity trends as well as O3 pollution for urban Beijing.

Potential of secondary aerosol formation from Chinese gasoline engine exhaust

Light-duty gasoline vehicles have drawn public attention in China due to their significant primary emissions of particulate matter and volatile organic compounds（VOCs）. However,little information on secondary aerosol formation from exhaust for Chinese vehicles and fuel conditions is available. In this study, chamber experiments were conducted to quantify the potential of secondary aerosol formation from the exhaust of a port fuel injection gasoline engine. The engine and fuel used are common in the Chinese market, and the fuel satisfies the China V gasoline fuel standard. Substantial secondary aerosol formation was observed during a 4–5 hr simulation, which was estimated to represent more than 10 days of equivalent atmospheric photo-oxidation in Beijing. As a consequence, the extreme case secondary organic aerosol（SOA） production was 426 ± 85 mg/kg-fuel, with high levels of precursors and OH exposure. The low hygroscopicity of the aerosols formed inside the chamber suggests that SOA was the dominant chemical composition. Fourteen percent of SOA measured in the chamber experiments could be explained through the oxidation of speciated single-ring aromatics. Unspeciated precursors, such as intermediate-volatility organic compounds and semi-volatile organic compounds, might be significant for SOA formation from gasoline VOCs. We concluded that reductions of emissions of aerosol precursor gases from vehicles are essential to mediate pollution in China.