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细菌半乳糖代谢通路及对细菌毒力的影响研究进展

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微生物学报 2025年第1期65卷 17-28页

作者：郑佳佳薛松杨晴晴方仁东曹雪峰西南大学动物医学院动物健康与动物性食品安全国际联合实验室重庆400715

半乳糖是自然界中广泛存在的一种单糖,不仅能作为碳源参与生物能量代谢,还能作为生物合成前体参与生物各类生理反应。在真核细胞中,半乳糖或相关衍生物能作为信号分子参与细胞间通讯。近期的研究发现,半乳糖能调控细菌内信号传导影响细... 详细信息

半乳糖是自然界中广泛存在的一种单糖,不仅能作为碳源参与生物能量代谢,还能作为生物合成前体参与生物各类生理反应。在真核细胞中,半乳糖或相关衍生物能作为信号分子参与细胞间通讯。近期的研究发现,半乳糖能调控细菌内信号传导影响细菌毒力,半乳糖因此被认为是细菌致病过程中低估的重要环境调控因子,但具体调控机制还未被充分揭示。本文结合最新研究数据,对细菌半乳糖代谢通路以及半乳糖代谢在细菌毒力、细菌-宿主互作等方面发挥的生物学功能进行综述,并对半乳糖代谢途径中关键蛋白(酶)作为开发新型疫苗潜在靶点进行讨论,为深入理解细菌致病机制和挖掘新型抗菌策略的相关研究提供新的思路和参考借鉴。

关键词：半乳糖细菌代谢通路毒力调控

基于UHPLC-QTOF-MS探讨高原鼠兔棕色脂肪低氧环境代谢分子机制

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重庆医科大学学报 2025年第2期50卷 267-274页

作者：薛华何雨昕郭子旭林凯歌白振忠曹学锋青海大学医学部西宁810001 青海大学高原医学研究中心西宁810001

目的:基于超高效液相色谱—四极杆飞行时间质谱联用(ultra high performance liquid chromatography quadrupole timeof-flight mass spectrometry,UHPLC-QTOF-MS)研究不同海拔下高原鼠兔棕色脂肪组织(brown adipose tissue,BAT)中的内源性差异代谢物及代谢通路,探讨BAT适应高原极端环境的代谢分子机制。方法:分别捕捉青海省果洛地区(4360 m)(MD组)和海北州门源地区(2900 m)(MY组)高原鼠兔各8只,利用UHPLC-QTOF-MS检测2组高原鼠兔BAT样本代谢产物,采用Simca软件对BAT代谢轮廓特征进行主成分分析(principal component analysis,PCA)和正交偏最小二乘判别分析(orthogonal projections to latent structures-discriminant analysis,OPLS-DA),结合t检验、火山图分析差异代谢物,并对差异代谢物进行KEGG代谢通路分析,构建气泡图。结果:PCA和OPLS-DA模式结果显示,2组BAT代谢组均表现出明显聚类型分布,这些代谢物参与体内糖代谢、脂代谢、氨基酸代谢、核苷酸代谢、胆汁酸代谢等多种生命活动。其中,葡萄糖-6-磷酸、胆酸、ADP-核糖、腺苷、脱氧胞苷、L-苯丙氨酸等代谢物水平在MD组高原鼠兔BAT中明显上调(P<0.05);去甲肾上腺素、硬脂酸、尿素、鸟氨酸、丙硫氧嘧啶等代谢物水平明显下调(P<0.05)。富集通路分析发现BAT代谢与苯丙氨酸、磷酸戊糖途径、酪氨酸、色氨酸等代谢通路相关。结论:高原极端环境影响机体的能量相关代谢通路有效激活BAT非颤抖产热,促进机体脂肪组织分化与白色脂肪褐变,增加BAT比重,以此适应高原极端环境。

关键词：超高效液相色谱—四极杆飞行时间质谱联用技术高原低氧高原鼠兔棕色脂肪组织代谢组学

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倾斜摄影三维模型在生产建设项目水土保持监测中的应用——以黄藏寺水利枢纽工程为例

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中国水土保持 2025年第2期 47-49页

作者：王玺圳程红刚曹雪峰水利部黄河水利委员会黄河上中游管理局陕西西安710021 西安黄河规划设计有限公司陕西西安710021

为提升祁连山地区黑河流域生产建设项目全过程水土保持监测水平,选取黑河干流首座控制性调蓄工程——黄藏寺水利枢纽工程,应用无人机倾斜摄影测量技术,构建了高精度的弃渣场实景三维模型,在此基础上计算了弃渣量、弃渣高度、挡墙高度等... 详细信息

为提升祁连山地区黑河流域生产建设项目全过程水土保持监测水平,选取黑河干流首座控制性调蓄工程——黄藏寺水利枢纽工程,应用无人机倾斜摄影测量技术,构建了高精度的弃渣场实景三维模型,在此基础上计算了弃渣量、弃渣高度、挡墙高度等指标,同时结合无人机正射遥感影像对弃渣场扰动面积及水土保持工程措施进行了解译计算,最后通过对比水土保持方案中弃渣场各指标的设计值,对水土保持措施落实情况进行了评价。结果表明:通过倾斜摄影测量技术构建的实景三维模型可精确计算弃渣场的各项水土保持措施指标,黄藏寺水利枢纽工程项目施工过程中实施的水土保持措施量基本符合水土保持方案设计值,土地扰动面积和弃渣量均在设计值之内。

关键词：倾斜摄影水土保持监测黄藏寺水利枢纽工程

The Research on Typhoon Wave Spectrum in Northwestern South China Sea

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Journal of Ocean University of China 2017年第1期16卷 8-14页

作者： SHI Hongyuan cao xuefeng WEN Xianhua SHI Maochong ZHAO Dongliang GUO Peifang Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100P.R.China Centre for Ports and Coastal Disaster Mitigation Ludong UniversityYantai 264025P.R.China Tianjin Research Institute of Water Transport Engineering of Ministry of Transport Tianjin 300456P.R.China

Based upon the one-year wind wave measurement data, collected from the South China Sea(SCS) at coordinates 20? 36.298?N, 110?45.433?E. by Acoustic Wave And Current(AWAC), we analyzed the wave characteristics and concluded that the most common wave direction was E and the second most common direction was ENE,the mean and the maximum values of significant height was 1.2 m and 4.36 m, respectively. The mean period was 4.0 s. We also evaluated the wave spectrums under conditions existing in three typhoons: Rumbi, Jeti and Utor. We found that unimodal spectrums occurred more often than others, and the maximum spectrum peak was 30.7911 m2 s. The minimum peak frequency was 0.0625 Hz, and the mean peak frequency was 0.126 Hz. The wave period is important for the design of marine structures, especially the position of peak frequency had a great influence on the stress calculation. Spectral analysis showed that the values of peak frequency distributed between 0.063 Hz and 0.217 Hz, with the mean value 0.114 Hz. We fit the normalized spectrum with 6 theoretical spectral models, out of which, the Wen spectrum, JONSWAP spectrum and Wallops spectrum were proved to give the best fit. What distinguished the Wen Spectrum from the rest was that it does not rely on the measured spectrum for parameter estimation. Hence, we recommend that the Wen spectrum should be widely used in marine construction.

关键词： typhoon wave wave spectrum theoretical wave spectrum

Flotation behavior of four dodecyl tertiary amines as collectors of diaspore and kaolinite

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Mining Science and Technology 2011年第2期21卷 249-253页

作者： Changmiao Liu Feng Ansheng Guo Zhenxu cao xuefeng Hu Yuehu Zhengzhou Institute of Multipurpose Utilization of Mineral Resources fAGS Zhengzhou 450006 China China National Engineering Research Center for Utilization of lndustrial Minerals Zhengzhou 450006 China School of Minerals Processing and Bio-engineering Central South University Changsha 410083 China

The flotation of diaspore and kaolinite by one of a series of tertiary amines（DRN,DEN,DPN and DBN） was *** tertiary amines show better floating recovery for kaolinite compared to *** maximum recovery D-value is 45%over a pH range from 3 to ***-IR spectra confirm the presence of hydroxyl groups on the surface of kaolinite and *** potential measurements show that the mineral surfaces are negatively charged over a wide pH *** of hydroxyl groups mainly accounts for the surface charging *** adsorption of tertiary amines onto the mineral surface is due mainly to electrostatic effects and the difference in electrostatic effect between a collector and the two minerals can explain the flotation *** electronic and steric effects from the substituent groups result in different collecting powers for the four tertiary amines.

关键词： Kaolinite Diaspore Amines collectors Froth flotation

Evaluating the Accuracy of ERA5 Wave Reanalysis in the Water Around China

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Journal of Ocean University of China 2021年第1期20卷 1-9页

作者： SHI Hongyuan cao xuefeng LI Qingjie LI Delei SUN Jiacheng YOU Zaijin SUN Qingying School of Civil Engineering Ludong UniversityYantai 264025China Institute of Ports and Coastal Disaster Mitigation Ludong UniversityYantai 264025China National Marine Environmental Monitoring Center Dalian 116023China Yantai Marine Environmental Monitoring Central Station State Oceanic AdministrationYantai 264006China Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Wave parameters, such as wave height and wave period, are important for human activities, such as navigation, ocean engineering and sediment transport, etc. In this study, wave data from six buoys around Chinese waters, are used to assess the quality of wave height and wave period in the ERA5 reanalysis of the European Centre for Medium-Range Weather Forecasts. Annual hourly data with temporal resolution are used. The difference between the significant wave height(SWH) of ERA 5 and that of the buoy varies from-0.35 m to 0.30 m for the three shallow locations;for the three deep locations, the variation ranges from-0.09 m to 0.09 m. The ERA5 SWH data show positive biases, indicating an overall overestimation for all locations, except for E2 and S1 where underestimation is observed. During the tropical cyclone period, a large(about 32%) underestimation of the maximum SWH in the ERA5 data is observed. Hence, the ERA5 SWH data cannot be used for design applications without site-specific validation. The difference between the annual wave period from ERA5 and the mean wave period from the buoys varies from-1.31 s to 0.4 s. Inter-comparisons suggest that the ERA5 dataset is consistent with the annual mean SWH. However, for the average period, the performance is not good, and half of the correlation coefficients in the four points are less 50%. Overall, the deep water area simulation effect is better than that in the shallow water.

关键词： wave hindcasting reanalysis ERA5 wave height wave period

Model-Simulated Coastal Trapped Waves Stimulated by Typhoon in Northwestern South China Sea

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Journal of Ocean University of China 2017年第6期16卷 965-977页

作者： cao xuefeng SHI Hongyuan SHI Maochong GUO Peifang WU Lunyu DING Yang WANG Lu College of Oceanic and Atmospheric Sciences Ocean University of China Qingdao 266100 P. R. China National Marine Environmental Monitoring Center Dalian 116023 P. R. China Ludong University School of Civil Engineering Yantai 264000 P. R. China The First Institute of Oceanography SOA Qingdao 266061 P. R. China

In this paper, we apply an unstructured grid coastal ocean model to simulate variations in the sea level and currents forced by two typhoons in the northwestern South China Sea(SCS). The model simulations show distinct differences for the two cases in which the typhoon paths were north and south of the Qiongzhou(QZ) Strait. In both cases, coastal trapped waves(CTWs) are stimulated but their propagation behaviors differ. Model sensitivity simulations suggest the dominant role played by alongshore wind in the eastern SCS(near Shanwei) and southeast of Hainan Island. We also examine the influence of the Leizhou Peninsula by changing the coastline in simulation experiments. Based on our results, we can draw the following conclusions: 1) The CTWs stimulated by the northern typhoon are stronger than the southern CTW. 2) In the two cases, the directions of the current structures of the QZ cross-transect are reversed. The strongest flow cores are both located in the middle-upper area of the strait and the results of our empirical orthogonal function analysis show that the vertical structure is highly barotropic. 3) The simulated CTWs divide into two branches in the QZ Strait for the northern typhoon, and an island trapped wave(ITW) around Hainan Island for the southern typhoon. 4) The Leizhou Peninsula plays a significant role in the distribution of the kinetic energy flux between the two CTW branches. In the presence of the Leizhou Peninsula, the QZ branch has only 39.7 percent of the total energy, whereas that ratio increases to 72.2 percent in its absence.

关键词： coastal trapped waves typhoon surge coastline influence South China Sea ocean modeling

Entropy regulation in LaNbO_(4)-based fergusonite to implement high-temperature phase transition and promising dielectric properties

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Journal of Advanced Ceramics 2023年第5期12卷 1067-1080页

作者： Deqin Chen Na Yan xuefeng cao Fengrong Li Laijun Liu Qinghua Shen Huanfu Zhou Chunchun Li Guangxi University Key Laboratory of Non-ferrous Metal Oxide Electronic Functional Materials and Devices College of Material Science and EngineeringGuilin University of TechnologyGuilin 541004China Guangxi Key Laboratory of Embedded Technology and Intelligent System Guilin University of TechnologyGuilin 541004China

High-entropy effect is a novel design strategy to optimize properties and explore novel *** this work,(La_(1/5)Nd_(1/5)Sm_(1/5)Ho_(1/5)Y_(1/5))NbO_(4)(5RNO)high-entropy microwave dielectric ceramics were successfully prepared in the sintering temperature(S.T.)range of 1210–1290℃via a solid-phase reaction route,and medium-entropy(La_(1/3)Nd_(1/3)Sm_(1/3))NbO_(4) and(La_(1/4)Nd_(1/4)Sm_(1/4)Ho_(1/4))NbO_(4)(3RNO and 4RNO)ceramics were *** effects of the entropy(S)on crystal structure,phase transition,and dielectric performance were *** entropy increase yields a significant increase in a phase transition temperature(from monoclinic fergusonite to tetragonal scheelite structure).Optimal microwave dielectric properties were achieved in the high-entropy ceramics(5RNO)at the sintering temperature of 1270℃for 4 h with a relative density of 98.2%and microwave dielectric properties of dielectric permittirity(ε_(r))=19.48,quality factor(Q×f)=47,770 GHz,and resonant frequency temperature coefficient(τ_(f))=–13.50 ppm/℃.This work opens an avenue for the exploration of novel microwave dielectric material and property optimization via entropy engineering.

关键词： high-entropy ceramics microwave dielectric property ion disorder far-infrared

藏药莪达夏醇提物介导葡萄糖-6-磷酸脱氢酶干预低氧性肺动脉高压机制研究

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中国医药导报 2025年第1期22卷 1-8页

作者：何雨昕薛华郭子旭白振忠曹学锋青海大学医学院青海西宁810001 青海大学高原医学研究中心青海西宁810001

目的探讨藏药莪达夏(OFB)对低氧性肺动脉高压(HPH)的干预作用及机制。方法选取130~150 g SPF级雄性SD大鼠60只,按照随机数字表法将其分为空白组、造模组、红景天组、低剂量组、中剂量组、高剂量组,每组10只。空白组大鼠饲养于青海大学SP... 详细信息

目的探讨藏药莪达夏(OFB)对低氧性肺动脉高压(HPH)的干预作用及机制。方法选取130~150 g SPF级雄性SD大鼠60只,按照随机数字表法将其分为空白组、造模组、红景天组、低剂量组、中剂量组、高剂量组,每组10只。空白组大鼠饲养于青海大学SPF级实验动物房,其余5组大鼠饲养于青海大学低压氧舱构建HPH模型;红景天组灌胃红景天醇提物200 mg/(kg·d),低、中、高剂量组分别灌胃OFB醇提物100、200、400 mg/(kg·d),空白组及造模组灌胃生理盐水,持续4周。比较各组大鼠右心室收缩压(RVSP)及右心肥厚指数(RVHI);评估各组大鼠肺动脉重塑程度;Western blot法及RT-qPCR检测各组大鼠葡萄糖-6-磷酸脱氢酶(G6PD)蛋白和mRNA表达;免疫组织化学染色法观察大鼠肺组织G6PD含量及分布;观察各组大鼠血清G6PD水平及肺组织NADP+/NADPH、总谷胱甘肽/氧化型谷胱甘肽(T-GSH/GSSG)、NADPH氧化酶(NOX)变化。结果造模组RVSP、RVHI高于空白组(P<0.05);低、中、高剂量组RVSP、RVHI低于造模组(P<0.05);中剂量组RVSP高于低剂量组(P<0.05);高剂量组RVSP低于中剂量组,RVHI高于中剂量组(P<0.05)。造模组血管壁面积占总血管面积的百分比(WA%)、血管壁厚度占血管外径的百分率(WT%)高于空白组(P<0.05);低、中、高剂量组WA%低于造模组(P<0.05),中剂量组WT%低于造模组(P<0.05);中剂量组WA%、WT%低于低剂量组(P<0.05)。造模组肺泡周围小血管G6PD阳性面积占比低于空白组(P<0.05);低、中、高剂量组肺泡周围小血管G6PD阳性面积占比低于造模组(P<0.05);高剂量组肺泡周围小血管G6PD阳性面积占比高于低剂量组(P<0.05)。造模组G6PD蛋白和mRNA表达低于空白组(P<0.05);低、中、高G6PD蛋白和mRNA表达低于造模组(P<0.05)。低剂量组肺组织NOX活力低于造模组(P<0.05);中剂量组血清G6PD及肺组织T-GSH/GSSG水平低于造模组(P<0.05);中剂量组血清G6PD水平低于低剂量组(P<0.05);高剂量组肺组织NADP+/NADPH、T-GSH/GSSG水平及NOX活力低于造模组(P<0.05)。结论400 mg/kg浓度OFB醇提物干预HPH效果最佳,其作用机制可能与下调G6PD减少磷酸戊糖途径下游信号传导有关。

关键词：莪达夏葡萄糖-6-磷酸脱氢酶磷酸戊糖途径低氧性肺动脉高压糖酵解