基于指标自动筛选的新疆开孔河流域生态健康评价

生态健康评价对了解区域生态健康状况和促进区域可持续发展具有重要意义,如何自动筛选出能反映生态系统特性的重要指标,是生态健康定量评估的关键问题。基于压力-状态-响应(PSR,Press-State-Response)框架和生态等级网络框架(EHN,Ecological Hierarchy Network),通过文献调研和因果分析建立要素层与指标层之间的交叉联系,构建了生态健康评价"网状"指标体系;在保证指标体系完备性基础上,通过结合主成分分析和熵权法的候选指标权重的客观计算,基于目标优化理论构建了评价指标的自动筛选模型,并基于中选指标计算了新疆开孔河流域2001—2017年生态健康指数(EHCI,Ecological Health Comprehensive Indexes),分析其空间分异和时间变化特征。结果表明:利用所建立的评价指标自动筛选模型,开孔河流域生态健康评价指标由31个候选指标自动筛选出了17个中选指标,用54.8%的指标表达了85.98%的信息,中选的17个指标在干旱/半干旱区域有关文献中应用较多,使用频次比例都在20%以上,其中归一化植被指数(NDVI,Normalized Difference Vegetation Index)、年降水量和植被覆盖度(FVC,Fractional Vegetation Coverage)3个指标的使用频次百分比均超过了50%,说明指标自动筛选模型的合理性;开孔河流域空间分布差异显著,总体上西北高、东南低,东南部和中部绿洲区外围生态健康状况较差,西北部河谷地带和中部两大绿洲区生态健康状况较好;17年来,流域生态质量整体趋于改善,显著改善区域占10.26%,远高于显著退化的1.61%,显著改善区域以孔雀河绿洲最为明显。开孔河流域生态健康的总体好转趋势说明区域生态综合治理取得一定成效。     

The protective effects of MSC‐EXO against pulmonary hypertension through regulating Wnt5a/BMP signalling pathway

The aim of the study was to explore the mechanism of mesenchymal stem cell‐derived exosomes (MSC‐EXO) to protect against experimentally induced pulmonary hypertension (PH). Monocrotaline (MCT)‐induced rat model of PH was successfully established by a single intraperitoneal injection of 50 mg/kg MCT, 3 weeks later the animals were treated with MSC‐EXO via tail vein injection. Post‐operation, our results showed that MSC‐EXO could significantly reduce right ventricular systolic pressure (RVSP) and the right ventricular hypertrophy index, attenuate pulmonary vascular remodelling and lung fibrosis in vivo. In vitro experiment, the hypoxia models of pulmonary artery endothelial cell (PAEC) and pulmonary vascular smooth muscle cell (PASMC) were used. We found that the expression levels of Wnt5a, Wnt11, BMPR2, BMP4 and BMP9 were increased, but β‐catenin, cyclin D1 and TGF‐β1 were decreased in MSC‐EXO group as compared with MCT or hypoxia group in vivo or vitro. However, these increased could be blocked when cells were transfected with Wnt5a siRNA in vitro. Taken together, these results suggested that the mechanism of MSC‐EXO to prevent PH vascular remodelling may be via regulation of Wnt5a/BMP signalling pathway.     

Nature of Novel 2D van der Waals Heterostructures for Superior Potassium Ion Batteries

Novel 2D van der Waals heterostructures with innovative bimetallic oxychloride (Bi‐ and Sb‐based oxychloride) nanosheets that are well dispersed on reduced graphene oxide nanosheets, are established through element engineering for superior potassium ion battery (PIBs) anodes. This material displays an exceptional electrochemical performance, obtaining a discharge capacity as high as 360 mAh g^?1 at 100 mA g^?1 after running 1000 cycles for over 9 months with a capacity preservation percentage of 88.5% and achieving a discharge capacity as high as 319 mAh g^?1 at 1000 mA g^?1, in addition to the low charge/discharge plateaus for anodes and promising full cell performance. More significantly, the nature of such 2D van der Waals heterostructures, including the element engineering for morphology control, the function of each component of heterostructures, the mechanism of potassium ion storage, and the process of K⁺ intercalation accompanied with the lattice distortion and chemical bond breakages, is explored in depth. This study is critical for not only paving the way for the practical application of PIBs but also shedding light on fundamentals of potassium ion storage in 2D van der Waals heterostructures.     

Temporal Reliability and Lateralization of the Resting-State Language Network

The neural processing loop of language is complex but highly associated with Broca''s and Wernicke''s areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca''s and Wernicke''s areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca''s area was found to be left lateralized, while the Wernicke''s area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR) on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability.     

PD-L1基因敲除小鼠构建及初步表型验证

目的 程序性死亡配体-1(PD-L1)是免疫调节途径的重要因子,是抗肿瘤免疫疗法中重要的靶标之一。利用CRISPR/Cas9技术成功构建PD-L1基因敲除小鼠模型,并初步分析其表型。方法 构建Cas9和sgRNA载体,并转录获得RNA,通过显微注射方式将RNA注射到C57BL/6小鼠受精卵中,经过鉴定获得F₀代阳性小鼠。F₀代小鼠与野生型C57BL/6小鼠交配获得F₁代杂合子小鼠,再通过F₁代小鼠自交获得F₂代纯合子小鼠品系。随后通过Real-Time PCR和流式实验分别检测PD-L1基因在mRNA和蛋白质水平上的表达情况。结果 Real-Time PCR和流式实验检测结果显示与野生型C57小鼠相比,PD-L1纯合子小鼠的PD-L1 mRNA相对表达水平和细胞上的蛋白质表达均有显著性下降,仅测定到本底的信号,证实已成功构建PD-L1基因敲除小鼠品系,为PD-L1体内基因功能研究提供了新的小鼠模型。     

RACK1对硼替佐米诱导的多发性骨髓瘤细胞凋亡及MAPK/ERK通路的影响

目的:探讨蛋白激酶C受体(Receptor for activated C kinase1,RACK1)对硼替佐米(Bortezomi,Bor)诱导的多发性骨髓瘤(Multiple myeloma,MM)细胞凋亡及MAPK/ERK通路的影响。方法:选取6例岳阳市第一人民医院收治的MM患者及6名正常体检者,用实时荧光定量PCR检测血浆及人MM细胞系中RACK1 m RNA的表达。将MM细胞分为3组:对照组(不干预)、Bor组(75n M的Bor干预12 h)和Bor+siRACK1组(RACK1 si RNA转染24 h后再行Bor干预)。CCK-8法检测各组细胞中的细胞存活率,Hoechest 33342染色检测细胞凋亡,Western Blot检测MAPK/ERK通路相关蛋白表达。结果:与正常体检者相比,MM患者血浆及MM细胞系中RACK1 m RNA表达显著增加(P0.05)。Bor作用12 h、24 h和48 h可显著降低MM细胞的存活率(P0.05)。与对照组相比,Bor组和Bor+siRACK1组细胞存活率显著降低,Bor+siRACK1组细胞存活率明显高于Bor组(P0.05)。Hoechest 33342染色显示对照组细胞核染色均一,未见凋亡小体,Bor组见少量凋亡小体,而Bor+siRACK1组细胞见大量凋亡小体,表现为核固缩或碎块状;与对照组相比,Bor组和Bor+siRACK1组细胞中多发性骨髓瘤细胞凋亡率显著增加(P0.05),Bor+siRACK1组多发性骨髓瘤细胞凋亡率明显高于Bor组(P0.05)。三组间多发性骨髓瘤细胞凋亡率对比差异有统计学意义(P0.05)。与对照组相比,Bor组和Bor+siRACK1组细胞中p-P38和p-ERK的表达显著降低,而Bor+siRACK1组p-P38和p-ERK的表达低于Bor组(P0.05),3组间P38和ERK的表达对比差异无统计学意义(P0.05)。结论:RACK1沉默可增强Bor诱导的MM细胞凋亡及生长抑制,其机制可能与MAPK/ERK途径抑制有关。     

One‐Step Controllable Synthesis of Catalytic Ni4Mo/MoOx/Cu Nanointerfaces for Highly Efficient Water Reduction

Currently, in addition to the electroactive non‐noble metal water‐splitting electrocatalysts, a scalable synthetic route and simple activity enhancement strategy is also urgently needed. In particular, the well‐controlled synthesis of the well‐recognized metal–metal nanointer face in a single step remains a key challenge. Here, the synthesis of Cu‐supported Ni₄Mo nanodots on MoO_x nanosheets (Ni₄Mo/MoO_x) with controllable Ni₄Mo particle size and d‐band structure is reported via a facile one‐step electrodeposition process. Density functional theory (DFT) calculations reveal that the active open‐shell effect from Ni‐3d‐band optimizes the electronic configuration. The Cu‐substrate enables the surface Ni–Mo alloy dots to be more electron‐rich, forming a local connected electron‐rich network, which boosts the charge transfer for effective binding of O‐related species and proton–electron charge exchange in the hydrogen evolution reaction. The Cu‐supported Ni₄Mo/MoO_x shows an ultralow overpotential of 16 mV at a current density of 10 mA cm^?2 in 1 m KOH, demonstrating the smallest overpotential, at loadings as low as 0.27 mg cm^?2, among all non‐noble metal catalysts reported to date. Moreover, an overpotential of 105 mV allows it to achieve a current density of 250 mA cm^?2 in 70 °C 30% KOH, a remarkable performance for alkaline hydrogen evolution with competitive potential for applications.     

燃煤污染型氟中毒患者氟暴露、骨相损伤程度与骨形成标志物的关系

慢性氟暴露是世界范围内的公共卫生问题之一.为研究燃煤污染型氟中毒患者中氟暴露、骨相损伤程度与骨形成标志物血清碱性磷酸酶(ALP)、骨钙素(BGP)之间的相关关系,以贵州省织金县荷花村(燃煤污染型地方性氟中毒病区)和安顺市张官村(非氟暴露村)为调查点,采集环境样品,采用氟离子选择电极法测定环境介质及食物中的氟含量.在知情同意的原则下,对295例氟暴露和85例非氟暴露调查对象进行氟斑牙、氟骨症诊断;收集其尿液及外周血,测定尿氟(UF)浓度、ALP活性和BGP含量.结果表明: 病区环境中大米、辣椒、玉米、饮水、黏土、菜土、煤以及室内外空气氟含量均明显高于对照区,但较以往报道数据降低;随着尿氟浓度的升高,ALP活性、BGP含量显著升高,氟骨症病情差异有统计学意义,氟斑牙病情差异无统计学意义;氟骨症病情与ALP活性、BGP含量呈正相关.表明燃煤污染型低氟暴露可引起人群的骨相损害,且ALP、BGP可用于评估氟骨症患者骨转换情况,在氟骨症的辅助诊断、疗效评估中有着一定的应用价值.     

复方扁咽宁对急性咽炎大鼠疗效及其机制

目的:观察复方扁咽宁对急性咽炎大鼠的治疗作用及其作用机理,为其临床应用提供依据。方法:采用氨水直接喷雾法复制大鼠急性咽炎模型,将其随机分为模型组、复方扁咽宁高、中、低剂量组,另取正常大鼠作为对照,每组10只,高、中、低剂量组剂量(g/kg)分别按28.8、14.4、7.2(生药量计)灌胃药物水提液,正常组与模型组给予等量蒸馏水,观察并记录各组大鼠的症状表现;于末次给药24 h后,腹主动脉采血,ELISA法检测血清中IL-1β及TNF-α的含量,采用HE染色法观察各组大鼠肺组织及肺支气管组织形态,透射电镜法观察气管纤毛形态。结果:模型组急性咽炎表现明显:咽部红肿、充血,气管及肺组织出现病理改变,血清中IL-1β及TNF-α的含量显著升高(与正常组比较,P＜0.05),提示造模成功;与模型组相比,复方扁咽宁低、中、高剂量组急性咽炎的症状如咽部红肿、充血等现象得到明显缓解,肺组织及肺支气管组织形态得到明显的改善,血清中IL-1β及TNF-α的含量显著下降,中剂量组和高剂量组疗效更显著。结论:复方扁咽宁可加速急性咽炎的康复进程,改善支气管及肺的组织形态,其作用机制可能与抑制血清IL-1β和 TNF-α的释放等有关。