In Vitro Protein Expression Profile of Campylobacter jejuni Strain NCTC11168 by Two-dimensional Gel Electrophoresis and Mass Spectrometry

Objective To investigate the protein expression profiles of the major food‐borne pathogen Campylobacter jejuni NCTC11168.Methods Membrane and soluble cellular proteins were extracted from the genome‐sequenced C.jejuni strain NCTC11168.Protein expression profiles were determined using two‐dimensional gel electrophoresis（2‐DE）.All the detected spots on the 2‐DE map were subjected to matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry（MALDI‐TOF/TOF） analysis.Results A total of 537 and 333 spots were detected from the whole cell and membrane‐associated proteins of C.jejuni NCTC11168 cultured on Columbia agar medium at 42 ℃ by 2‐DE and Coomassie Brilliant Blue staining,respectively.Analyses of whole cell and membrane‐associated proteins included 399 and 133 spots,respectively,which included 182 and 53 functional proteins identified by MALDI‐TOF/TOF analysis.Conclusion The comprehensive expression protein profiles of C.jeuni NCTC11168 obtained in this study will be useful for elucidating the roles of these proteins in further pathogenesis investigation.

Proteome Analysis of Neisseria meningitidis Serogroup Strains C Associated with Outbreaks in China

Objective During 2003-2005, an outbreak of meningitis due to Neisseria meningitidis serogroup C occurred in China. With the aim to find strain clues result in the final epidemics, the ancestral strain 053442, a clinical isolate, and a carrier strain 053426 with different gene type were analyzed. Methods Clinical strain 053442 and carrier strain 053426 were cultured on GC agar plates under the same condition. Two-dimensional electrophoresis was performed using the pH 3–10 nonlinear IPG strips of 24 cm length, and all the protein spots were identified by matrix-assisted laser desorption/ionization time of flight spectrometry. Results 502 and 380 protein spots were identified in 053426 and 053442 respectively, relating to 266 and 202 different genes covering a wide range of cellular functions. The express volume and number of proteins involved in energy metabolism, protein synthesis and amino acid biosynthesis in 053426 were higher than in 053442. Virulence factor Opa, Opc and a series of proteins involved in pilus assembly and retraction were identified in 053442, which appear to be of primary importance in colonization and invasion of human cells. Compared to 053442, virulence protein species were less in 053426, with lower express volumes too. No Opa and Opc were detected in 053426. Conclusion The different protein expression profiles of the clinical strain 053442 and carrier strain 053426 in the present study provide some clues of the different pathogenicity of the two strains, which may account for result in the final epidemics.

High Capacity Data Hiding in Encrypted Image Based on Compressive Sensing for Nonequivalent Resources

To fulfill the requirements of data security in environments with nonequivalent resources,a high capacity data hiding scheme in encrypted image based on compressive sensing(CS)is proposed by fully utilizing the adaptability of CS to nonequivalent resources.The original image is divided into two parts:one part is encrypted with traditional stream cipher;the other part is turned to the prediction error and then encrypted based on CS to vacate room simultaneously.The collected non-image data is firstly encrypted with simple stream cipher.For data security management,the encrypted non-image data is then embedded into the encrypted image,and the scrambling operation is used to further improve security.Finally,the original image and non-image data can be separably recovered and extracted according to the request from the valid users with different access rights.Experimental results demonstrate that the proposed scheme outperforms other data hiding methods based on CS,and is more suitable for nonequivalent resources.

颈动脉内膜剥脱改良根治术(分叉上移术)初步探索

颈动脉内膜剥脱术(CEA)是治疗颅外段颈动脉狭窄、预防缺血性脑卒中发生的重要手术方式。经过70年的发展,CEA的有效性和安全性已通过多项大型临床随机对照试验验证,并衍生出多种手术方式。传统CEA的颈动脉切口为颈总动脉至颈内动脉的纵向切口,由于直接原位缝合术后易发生再狭窄,因而通常需使用补片。目前,临床主要应用的术式是补片成形CEA和外翻式CEA,各有优劣,关于其手术经验和改良方案已有研究报道。颈动脉内膜剥脱改良根治术(分叉上移术)是结合CEA的手术原理及临床经验而提出的手术方式,其特点在于无需使用补片,术后的融合管腔直径大,具备临床研究价值,但较难处理高位颈动脉病变,其有效性、安全性及适用人群尚需进一步进行临床试验的探索。由于重建颈动脉分叉,该术式也具有推广至其他累及颈动脉分叉的颈部病变(如颈动脉体瘤)的潜在价值。本文主要针对其应用背景、临床应用现状及技术要点加以述评,以期能够为临床工作和研究提供参考。

Forecasting S&P 500 Stock Index Using Statistical Learning Models

Forecasting the movement of stock market is a long-time attractive topic. This paper implements different statistical learning models to predict the movement of S&P 500 index. The S&P 500 index is influenced by other important financial indexes across the world such as commodity price and financial technical indicators. This paper systematically investigated four supervised learning models, including Logistic Regression, Gaussian Discriminant Analysis (GDA), Naive Bayes and Support Vector Machine (SVM) in the forecast of S&P 500 index. After several experiments of optimization in features and models, especially the SVM kernel selection and feature selection for different models, this paper concludes that a SVM model with a Radial Basis Function (RBF) kernel can achieve an accuracy rate of 62.51% for the future market trend of the S&P 500 index.

左生殖静脉-下腔静脉转流术治疗胡桃夹综合征合并精索静脉曲张一例

胡桃夹综合征是一种罕见疾病,可导致患者出现蛋白尿、肾功能受损及生殖静脉曲张等系列症状。传统开放手术方式首选左肾静脉转位术,但手术创伤较大,术后近、远期并发症较多,影响患者生活质量。本文报道1例胡桃夹综合征合并左精索静脉曲张的男性青年患者,采用左生殖静脉-下腔静脉转流术并左精索静脉高位结扎术的手术方式,取得了良好治疗效果。该手术方式为胡桃夹综合征合并精索静脉曲张患者提供了新的治疗思路,值得临床借鉴。

月经紊乱,下肢浮肿,急性肾损伤--罕见盆腔占位的“瘤栓事件”

低级别子宫内膜间质肉瘤(low-grade endometrial stromal sarcoma,LG-ESS)是一种罕见的子宫恶性肿瘤,在所有子宫恶性肿瘤中占比不足1%,目前国内外尚无关于LG-ESS导致急性完全性下腔静脉阻塞的报道。2020年11月,北京协和医院血管外科接诊1例LG-ESS患者,临床表现为月经紊乱、右下肢凹陷性水肿、突发恶心、少尿、肌酐升高,影像学提示下腔静脉完全性阻塞,通过多学科协作共同决策,采用分期手术联合内分泌治疗成功救治该患者,其诊疗过程体现了多学科协作在疑难重症患者诊治中的重要作用。

Recombinant vascular basement-membrane-derived multifunctional peptide inhibits angiogenesis and growth of hepatocellular carcinoma

AIM: To investigate the anti-angiogenic and antitumor activities of recombinant vascular basement membrane-derived multifunctional peptide (rVBMDMP) in hepatocellular carcinoma (HCC). METHODS: HepG2, Bel-7402, Hep-3B, HUVE-12 and L-02 cell lines were cultured in vitro and the inhibitory effect of rVBMDMP on proliferation of cells was detected by MTT assay. The in vivo antitumor efficacy of rVBMDMP on HCC was assessed by HepG2 xenografts in nude mice. Distribution of rVBMDMP, mechanism by which the growth of HepG2 xenografts is inhibited, and microvessel area were observed by proliferating cell nuclear antigen (PCNA) and CD31 immunohistochemistry. RESULTS: MTT assay showed that rVBMDMP markedly inhibited the proliferation of human HCC (HepG2, Bel-7402, Hep-3B) cells and human umbilicalvein endothelial (HUVE-12) cells in a dose-dependent manner, with little effect on the growth of L-02 cells. When the IC50 was 4.68, 7.65, 8.96, 11.65 and 64.82 μmol/L, respectively, the potency of rVBMDMP to HepG2 cells was similar to 5-fluorouracil (5-FU) with an IC50 of 4.59 μmol/L. The selective index of cytotoxicity to HepG2 cells of rVBMDMP was 13.8 (64.82/4.68), which was higher than that of 5-FU [SI was 1.9 (8.94/4.59)]. The VEGF-targeted recombinant humanized monoclonal antibody bevacizumab (100 mg/L) did not affect the proliferation of HepG2, Bel-7402, Hep-3B and L-02 cells, but the growth inhibitory rate of bevacizumab (100 mg/L) to HUVE-12 cells was 87.6% ± 8.2%. Alternis diebus intraperitoneal injection of rVBMDMP suppressed the growth of HepG2 xenografts in a dose-dependent manner. rVBMDMP (1, 3, 10 mg/kg) decreased the tumor weight by 12.6%, 55.9% and 79.7%, respectively, compared with the vehicle control. Immunohistochemical staining of rVBMDMP showed that the positive area rates (2.2% ± 0.73%, 4.5% ± 1.3% and 11.5% ± 3.8%) in rVBMDMP treated group (1, 3, 10 mg/kg) were significantly higher than that (0.13% ± 0.04%) in the control group (P < 0.01). The positive area rates (19.0% ± 5.7%, 12.2% ± 3.5% and 5.2% ± 1.6% ) of PCNA in rVBMDMP treated group (1, 3, 10 mg/kg) were significantly lower than that (29.5% ± 9.4%) in the control group (P < 0.05). rVBMDMP at doses of 1, 3 and 10 mg/kg significantly reduced the tumor microvessel area levels (0.26% ± 0.07%, 0.12% ± 0.03% and 0.05% ± 0.01% vs 0.45% ± 0.15%) in HepG2 xenografts (P < 0.01), as assessed by CD31 staining. CONCLUSION: rVBMDMP has effective and unique anti-tumor properties, and is a promising candidate for the development of anti-tumor drugs.

基于Al_(0.8)Sc_(0.2)N压电薄膜MEMS声波器件的研制

该文介绍了一种由5×5个半径为200μm圆形阵列组成,应用于水听器的高性能压电微机电系统(MEMS)声波器件,尺寸为3 mm×3 mm。采用钪掺杂(质量分数为20%)增强了AlN薄膜的压电系数,并通过双电极结构配置及优化结构尺寸来增强声压作用下的电信号输出,以实现压电MEMS声波器件具有更好的接收灵敏度。声波器件在空气中的接收灵敏度为-166.8 dB(Ref.1 V/μPa),比相同结构基于AlN薄膜的声波器件约高2.6 dB。在50 Hz~3 kHz带宽范围内,器件灵敏度曲线变化小于1.5 dB,具有平坦的声学响应。结果表明,基于Al_(0.8)Sc_(0.2)N薄膜的压电MEMS声波器件具有更高的接收灵敏度,经水密封装制成的水听器可应用于管道泄漏探测及海洋噪声监测等工程中。

高淳油菜花期低温连阴雨灾害评估

花期是油菜生长的关键时期,为定量评估油菜花期低温连阴雨灾害的影响,本文通过分析1970—2019年高淳油菜产量和灾情数据,构建了油菜气候产量与油菜花期低温连阴雨指数的回归模型。研究表明,1970—2019年高淳油菜产量和年极端最低气温均呈升高趋势,油菜花期低温天数呈下降趋势,≤10℃的低温天数下降趋势更为明显;油菜花期低温天数与产量有一定的相关性,花期最低气温及油菜花期低温天数的变化趋势,可能与全球气候变暖背景有关,油菜花期平均气温的升高和低温天数的减少有助于提高油菜产量;近50 a中有1/5的年份未出现连阴雨,这些年份油菜生长较好;油菜花期连阴雨日数和低温连阴雨指数均呈下降趋势,油菜花期低温连阴雨指数与气候产量存在明显的反比关系。油菜花期低温连阴雨对油菜品质等特征的影响尚待进一步研究。

A novel strategy for screening mutations in the voltage-gated sodium channel gene of Aedes albopictus based on multiplex PCR-mass spectrometry minisequencing technology

Background The current prevention and control strategy forAedes albopictus heavily relies on comprehensive management, such as environmental management and chemical control. However, the wide application of pyrethroids has facilitated the development of insecticide resistance, primarily via mutations in the voltage-gated sodium channel (VGSC) gene. This study aims to develop a novel strategy for detecting mutations in the VGSC gene inAe. albopictus using multiplex PCR-mass spectrometry (MPCR-MS) minisequencing technology.Methods We established a new strategy for detecting mutations in the VGSC gene inAe. albopictus using MPCR-MS minisequencing technology. MPCR amplification and mass probe extension (MPE) were first used, followed by single nucleotide polymorphism (SNP) typing mass spectrometry, which allows the simultaneous detection of multiple mutation sites of the VGSC gene in 96 samples ofAe. albopictus. A total of 70 wild-collectedAe. albopictus were used to evaluate the performance of the method by comparing it with other methods.Results Three target sites (1016, 1532, 1534) in the VGSC gene can be detected simultaneously by double PCR amplification combined with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry, achieving a detection limit of 20 fg/μl. We applied this method to 70 wild-collectedAe. albopictus, and the obtained genotypes were consistent with the routine sequencing results, suggesting the accuracy of our method.Conclusions MPCR-MS minisequencing technology provides a sensitive and high-throughput approach toAe. albopictus VGSC gene mutation screening. Compared with conventional sequencing, this method is economical and time-saving. It is of great value for insecticide resistance surveillance in areas with a high risk of vector-borne disease.

Biomimetic construction of oriented lamellar Col/nHAP composite scaffolds and mediation of macrophages to promote angiogenesis and bone regeneration

Pore characteristics have been identified as key design parameters for osteoimmunomodulation.The strategy reported here is to create an appropriate immune microenvironment by regulating pore characteristics of scaffolds,thereby promoting early angiogenesis and enhancing osteogenesis.A series of collagen/nanohydroxyapatite(Col/nHAP)composite scaffolds with ordered lamellar structures and different layer spacings were prepared by mimicking the ordered lamellar topology of the bone matrix.Our research indicated that the layer spacing and ordered topology of the scaffold exerted an important influence on phenotype transformation of macrophages and the secretion of angiogenic factors.The Col/nHAP-O(135)with large layer spacing not only supported cell attachment and diffusion in vitro,but also promoted early angiogenesis by timely switching from M1 to M2 macrophage phenotype.In vivo data showed that the layer spacing and the ordered structure of the scaffold synergistically regulated the inflammatory response and triggered macrophages to secrete more angiogenesis related cytokines.Col/nHAP-O(135)considerably promoted the neovascularization and new bone formation in the defect site,indicating that Col/nHAPO(135)could significantly enhance the osteogenic activity of stem cells with the involvement of macrophages.

tRNA来源的小RNA在心血管疾病中的研究进展

转运RNA来源的小RNA(tsRNA)是一类由转运RNA特异性断裂产生的新型非编码RNA,具有多种调控机制,参与多种疾病的发生、发展过程。近年来,多项研究证实tsRNA在心血管疾病中发挥重要作用。该文主要对tsRNA生物学发生、调控机制及其在心血管疾病中的研究进展进行综述,以期为心血管疾病诊治提供新的研究方向。

Decoy-state method for quantum-key-distribution-based quantum private query

The quantum private query(QPQ)is a quantum solution for the symmetrically private information retrieval problem.We study the security of quantum-key-distribution-based QPQ with weak coherent pulses.The result shows that multiphoton pulses have posed a serious threat to the participant’s privacy in QPQ protocols.Then we propose a decoy-state method that can help the honest participant detect the attack by exploiting multiphoton pulses and improving the key distillation process to defend against such attack.The analysis demonstrates that our decoy-state method significantly improves the security of the QPQ with weak coherent pulses,which solves a major obstacle in the practical application of the QPQ.

High-payload completely reversible data hiding in encrypted images by an interpolation technique

本文提出一种新型的高容量密文图像可逆信息隐藏方法。与直接在密文图像中嵌入数据不同,内容拥有者首先利用插值技术在加密前估算出嵌入的位置并生成地图;其次,数据隐藏者根据位置地图,通过翻转密文图像的最高有效位来嵌入额外的数据。在接收端口,接收者在提取嵌入数据和重构图像前先解密图像。实验结果表明该方法可实现完全可逆,即数据提取和图像恢复都无误。此外,与现有大多数密文图像可逆隐藏方案相比,本方案可实现更高的嵌入容量。

The physics of fast radio bursts

In 2007, a very bright radio pulse was identified in the archival data of the Parkes Telescope in Australia, marking the beginning of a new research branch in astrophysics. In 2013, this kind of millisecond bursts with extremely high brightness temperature takes a unified name, fast radio burst(FRB). Over the first few years, FRBs seemed very mysterious because the sample of known events was limited. With the improvement of instruments over the last five years, hundreds of new FRBs have been discovered.The field is now undergoing a revolution and understanding of FRB has rapidly increased as new observational data increasingly accumulate. In this review, we will summarize the basic physics of FRBs and discuss the current research progress in this area.We have tried to cover a wide range of FRB topics, including the observational property, propagation effect, population study,radiation mechanism, source model, and application in cosmology. A framework based on the latest observational facts is now under construction. In the near future, this exciting field is expected to make significant breakthroughs.

Tightness and sweet spot formation in moldic-pore-type dolomite reservoirs: The middle Ordovician Majiagou Formation in the eastern Ordos Basin, central China

The diagenetic evolution of the moldic-pore-containing gypsum dolomites of the Middle Ordovician Majiagou Formation in the eastern Ordos Basin,central China,was studied by means of petrological,mineralogical,and geochemical analyses,to improve our understanding of heterogeneity in high-quality reservoirs.The aim of the study was to elucidate the processes that resulted in reservoir tightness and the formation of sweet spots,to guide future exploration.Results show that the moldic-pore-containing gypsum dolomites are the most favorable reservoir in the study area,with a mean porosity of 4.96%and a mean permeability of 0.748 mD.The development and preservation of gypsum moldic pores were the main factors causing reservoir heterogeneity.Specifically,moldic pore development was controlled by the sedimentary microfacies,whereas pore preservation was related to dissolution and filling during telogenetic diagenesis.There were three main dissolution-filling stages that took place in three settings:penecontemporaneous,epigenetic,and burial.These processes controlled the formation of reservoir sweet spots.Early-consolidated dolomite deposits were frequently exposed to the atmosphere in the penecontemporaneous environment under the influence of high-frequency sedimentary cycles,which led to the dissolution of evaporite minerals and consequent formation of gypsum moldic pores,accompanied by infilling by freshwater calcite.During epigenesis,the porosity initially increased due to karstification,then significantly decreased because of calcite infilling resulting from long subaerial exposure(120 Myr),which contributed to reservoir heterogeneity.Finally,during burial the high-temperature and high-pressure conditions led to chemical compaction and continuous tightening of the reservoir,although some burial dissolution also took place.In conclusion,the variable paleo-topography resulted in differences in the intensity of pore filling among the blocks in the study area,resulting in reservoir heterogeneity.

Disease X Testing:The results of an international external quality assessment exercise

The United Nations Secretary-General Mechanism(UNSGM)for investigation of the alleged use of chemical and biological weapons is the only established international mechanism of this type under the UN.The UNGSM may launch an international investigation,relying on a roster of expert consultants,qualified experts,and analytical laboratories nominated by the member states.Under the framework of the UNSGM,we organized an external quality assurance exercise for nominated laboratories,named the Disease X Test,to improve the ability to discover and identify new pathogens that may cause possible epidemics and to determine their animal origin.The“what-if”scenario was to identify the etiological agent responsible for an outbreak that has tested negative for many known pathogens,including viruses and bacteria.Three microbes were added to the samples,Dabie bandavirus,Mammarenavirus,and Gemella spp.,of which the last two have not been taxonomically named or published.The animal samples were from Rattus norvegicus,Marmota himalayana,New Zealand white rabbit,and the tick Haemaphysalis longicornis.Of the 11 international laboratories that participated in this activity,six accurately identified pathogen X as a new Mammarenavirus,and five correctly identified the animal origin as R.norvegicus.These results showed that many laboratories under the UNSGM have the capacity and ability to identify a new virus during a possible international investigation of a suspected biological event.The technical details are discussed in this report.

经腹膜后第十肋部分切除治疗CrawfordⅣ型胸腹主动脉瘤及复杂腹主动脉瘤初探

目的评价一种部分切除第十肋腹膜后入路显露CrawfordⅣ型胸腹主动脉瘤及复杂腹主动脉瘤的手术方式。方法回顾性分析2014年至2019年7例通过部分切除第十肋腹膜后入路治疗Crawford IV型胸腹主动脉瘤及复杂腹主动脉瘤患者的临床资料及随访数据。结果7例经腹膜后入路手术的主动脉瘤患者1例(14.3%)合并马凡综合征,5例进行了左肾动脉重建(71.4%)。所有患者术后未出现心肺并发症及肾衰竭等严重并发症,住院期间术前及术后血清肌酐差异无统计学意义(P=0.205)。随访未发现远期血管狭窄。结论部分切除第十肋腹膜后入路可避免切开胸膜和横膈,在膈下完成主动脉的显露,具有较小的创伤和较低的并发症风险。

日本血吸虫虫卵排泄分泌物中具有诊断价值的抗原分子的初步鉴定

目的鉴定日本血吸虫虫卵分泌排泄物(ESA)中有血吸虫病诊断价值蛋白分子,为建立新的高敏感性和特异性的日本血吸虫病诊断方法奠定基础。方法日本血吸虫尾蚴感染家兔后42d,解剖家兔,取肝脏,匀浆后收集虫卵,置于PBS中,4℃过夜,收集上清,制备虫卵排泄分泌物。以虫卵排泄分泌物包被酶标板,采用ELISA检测不同感染度、不同感染时间小鼠血清抗体滴度。同时以虫卵ESAELISA分别检测血吸虫病患者血清、健康人血清和弓形虫病患者血清,观察虫卵ESA用于血吸虫病诊断的敏感性和特异性及交叉反应性。通过一维电泳免疫印迹、二维电泳免疫印迹和飞行质谱分析,鉴定虫卵ESA中具有诊断潜能的蛋白分子。结果ELISA检测结果显示血吸虫感染小鼠血清中抗虫卵ESA抗体IgG水平随着感染时间的延长而升高,且与血吸虫感染度呈正相关,在感染早期即检出相应抗体。虫卵ESA检测血吸虫病患者血清的敏感性为97.2%,检测健康人血清的特异性为95.2%,与弓形虫病患者血清的交叉反应性为25.0%。一维电泳免疫印迹试验显示血吸虫感染兔血清可识别170×103、150×103、130×103、100×103、72×103、70×103、30×103ku左右的ESA蛋白;二维电泳免疫印迹试验显示血吸虫感染兔血清可识别8个蛋白斑点,质谱分析其中1个蛋白斑点为日本血吸虫主要的虫卵蛋白P40。结论日本血吸虫虫卵排泄分泌抗原具有一定的血吸虫病诊断与早期诊断价值,虫卵的主要蛋白P40可能是一个具有诊断潜能的抗原分子。