多重TaqMan荧光定量PCR检测仔猪先天性震颤相关病毒方法的建立与应用

旨在研究能够快速、准确、灵敏地鉴别、诊断引起仔猪先天性震颤的猪非典型瘟病毒(Atypical porcine pestivirus,APPV)、猪瘟病毒(Classical swine fever virus,CSFV)、猪圆环病毒3型(Porcine circoviruses type 3,PCV-3)及猪捷申病毒1型(Porcine teschovirus 1,PTV-1)的方法。通过对GenBank中登录的APPV的NS3基因序列、CSFV的E2基因序列、PCV-3的ORF2基因序列和PTV-1的VP1基因序列进行分析,设计针对4种病毒的特异性引物和TaqMan水解探针。通过对反应条件和反应程序进行优化,拟建立针对仔猪先天性震颤相关病毒的多重TaqMan荧光定量PCR检测方法。结果显示,研究得到的多重TaqMan荧光定量PCR检测方法能够特异性检测APPV、CSFV、PCV-3和PTV-1,而与其他病原无交叉反应;该研究方法对APPV、CSFV、PCV-3和PTV-1的最低检测量分别为1μl 9.2×10^2拷贝、48拷贝、56拷贝和17拷贝。重复性试验结果显示,组内、组间变异系数均小于2.10%,重复性和稳定性较为突出。用该方法对273份临床样品进行检测,结果显示,APPV、CSFV、PTV-1和PCV-3的阳性率分别为20.5%、2.9%、1.5%和10.6%,其中APPV、CSFV二者共同感染的检出率为1.5%,APPV、PCV-3二者共同感染的检出率为4.4%,APPV、PTV-1二者共同感染的检出率为1.5%,APPV、CSFV、PCV-3共同感染的检出率为1.1%。该检测方法操作简单、耗时短、不易对环境造成污染,检测结果灵敏、准确,基于该方法对四川地区仔猪先天性震颤相关病毒共感染情况进行的流行病学调查,可以为后期研究提供重要的数据基础。

Growth induction of hepatic stimulator substance in hepatocytes through its regulation on EGF receptors

The cytosolic liver-specific growth factor-hepatic stimulator substance (HSS) has been shown to be able to amplify the rat hepatocyte proliferation responded to EGF. In order to get more insight into the mechanism, the regulatory effect of HSS on EGF-receptor(EGF-R) and the receptor phosphorylation at molecular level was studied. HSS partially purified from weanling rat liver was given to cultured hepatocytes and its influence on EGF-R specific binding and internalization as well as mRNA expression were investigated. The results showed that preincubation of hepatocytes with HSS could lead to an increase in [125I]-EGF binding to its receptors and inhibit EGFinduced receptor down-regulation. Furthermore, the overexpression of EGF-R mRNA stimulated by HSS was seen during 2-12 h after the incubation. Additionally, it was demonstrated with human hepatoma sMMC-7721 cells in Western blot that the EGF-R expression and the receptor autophosphorylation were increased with dose/timedependency after HSS treatment. These results strongly suggest that the mechanism of HSS action on hepatocyte growth might be related to its modulation on EGF-R and receptor-mediated signaling transduction.

Development and Application of Oil-Spill Risk Assessment Model for Offshore Pipeline

To the potential oil-spill risk caused by offshore pipeline more attention has been paid after the Dalian oil spill incident from oil-pipeline explosion. Since then an issue about how to prevent and control the sudden oil-spill from the offshore pipeline has been raised. In this paper, we proposed an optimized model to analyze the main causes(probability) of spill and the consequence with the fuzzy comprehensive assessment model. Considering the complicated assessment process for oil-spill, the assessment factor system involving the spill probability and consequence was established based on the operative manual and statistic leakage/damage data of offshore pipeline in order to estimate the integrated spill risk score automatically. The evaluated factors of spill probability could be grouped into five aspects: corrosion, fatigue, national damage, third party, and operational fault; the consequence evaluated factors of spill included hazard of oil and impact-controlling capability. With some modifications based on experts' opinions, each of the evaluated factors in our work was developed with a relative weight and evaluation criterion. A test example for an offshore pipeline in the Bohai waters was described to show how the model can be used for an actual case in more detail. By using the oil-spill risk assessment model, it is easy to determine the risk level associated with the ongoing activity and management level and hence to take the risk mitigation action immediately.

Analysis of impacting factors on polarimetric SAR oil spill detection

Polarimetric synthetic aperture radar （SAR） oil spill detection parameters conformity coefficient （μ）, Muller matrix parameters （｜C｜,B0 ）, the eigenvalues of simplified coherency matrix （λnos） and the influence of SAR observing parameters, ocean environment and noise level are investigated. Radarsat-2 data are used to make systematic analysis of polarimetric parameters for different incidences, wind speeds, noise levels and the ocean phenomena （oil slick and look likes）. The influence of the SAR observing parameters, the ocean environment and the noise level on the typical polarimetric SAR parameter conformity coefficient has been analyzed. The results indicate that conformity coefficient cannot be simply used for oil spill detection, which represents the image signal to the noise level to some extent. When the signals are below the noise level for the oil slick and the look likes, the conformity coefficients are negative; while the signals above the noise level corresponds to positive conformity coefficients. For dark patches （low wind and biogenic slick） with the signal below the noise, polarization features such as conformity coefficient cannot separate them with oil slick. For the signal above the noise, the oil slick, the look likes （low wind and biogenic slick） and clean sea all have positive conformity coefficients, among which, the oil slick has the smallest conformity coefficient, the look likes the second, and the clean sea the largest value. For polarimetric SAR data oil spill detection, the noise plays a significant role. So the polafimetric SAR data oil spill detection should be carried out on the basis of noise consideration.

Constructing the wolfberry(Lycium spp.) genetic linkage map using AFLP and SSR markers

Genetic linkage maps are important for quantitative trait locus(QTL) and marker-assisted selection breeding. The wolfberry(Lycium spp.) is an important food and traditional medicine in China. However, few construction genetic linkage maps have been reported because of the lack of genomic and genetic resources. In this study, a population of 89 F1 seedings was derived from a cross between two heterozygous parents, L. chinense var. potaninii ‘BF-01’(female)and L. barbarum var. auranticarpum ‘NH-01’(male), in order to construct a genetic linkage map using simple sequence repeat(SSR) and amplified fragment length polymorphism(AFLP) markers based on the double pseudo-test cross mapping strategy. The resulting genetic map consisted of 165 markers(74 AFLPs and 91 SSRs) distributed across 12 linkage groups and spanned a total length of 557.6 cM with an average distance of 3.38 cM between adjacent markers.The 12 linkage groups contained 3 to 21 markers and ranged in length from 8.6 to 58.3 cM. Twenty-nine segregated markers distributed in the map were mainly located on LG4 and LG9 linkage groups at P<0.05. This is the first linkage map of Lycium species using SSR and AFLP markers, which can serve as basis for improving genes and selective breeding of the genome assembly.

An experimental study on oil droplet size distribution in subsurface oil releases

Oil droplet size distribution （ODSD） plays a critical role in the rising velocity and transport of oil droplets in subsurface oil releases. In this paper, subsurface oil release experiments were conducted to study ODSD under different experimental conditions in a laboratory water tank observed by two high-speed cameras in March and April 2017. The correlation formulas Oh=lO.2Re-~ and Oh=39.2Re-1 （Re represents Reynolds number and Oh represents Ohnesorge number） were established to distinguish the boundaries of the three instability regimes in dimensionless space based on the experimental results. The oil droplet sizes from the experimental data showed an excellent match to the Rosin-Rammler distribution function with determination coefficients ranging from 0.86 to 1.00 for Lvda 10-1 oil. This paper also explored the influence factors on and change rules ofoil droplet size. The volume median diameter d50 decreased steadily with increasing jet velocity, and a sharp decrease occurred in the laminar-breakup regime. At Weber numbers （We） 〈100, the orifice diameter and oil viscosity appeared to have a large influence on the mean droplet diameter. At 100〈We〈1 000, the oil viscosity appeared to have a larger influence on the relative mean droplet diameter.

叶黄素对兔创伤性颞下颌关节强直的预防作用研究

目的:探讨叶黄素对兔创伤性颞下颌关节强直的作用。方法:将16只新西兰大白兔随机分为空白对照组及叶黄素干预组(实验组),所有实验动物均在保护关节囊的前提下建立创伤性颞下颌关节强直模型。术后实验组口服叶黄素10 mg·kg^(-1)·d^(-1),连续给药4周。比较2组动物的最大开口度、体重、组织学、影像学、骨代谢指标等方面的差异。采用GraphPad Prism 9.4.0软件包对数据进行统计学分析。结果:术后实验组动物体重、开口度、血清骨钙素浓度、CT测量的髁突表面积及体积显著高于对照组(P<0.05)。组织形态学观察显示,2组实验动物髁突残端可见编织骨和新生骨,纤维中有时可见软骨化生灶,偶可见肉芽组织和陈旧性出血。实验组髁突纤维层增厚,细胞增殖活跃,细胞层次更加明显。结论:叶黄素对创伤性颞下颌关节强直的发生有一定预防作用,其作用机制可能与叶黄素促进骨形成、提高血清骨钙素浓度等有关。

基于IPRAN网络演进的5G回传承载方案探讨

随着互联网技术的发展,高能效、高效率、覆盖范围广、资源利用率高的通信网络技术优势已成为网络演进过程中持续追求的目标。本文通过分析5G回传承载方案的研究现状,建立5G回传承载的目标构架,并基于IPRAN网络演进,对5G回转承载方案的两大组成部分展开讨论,着重分析了功能增强承载方案中的EVPN技术、Segment Routing技术、网络切片技术与SND技术等核心技术,提出相关可行性建议,希望可以为相关从业人员提供参考。

Characteristics of platinum-group elements in basalts from spreading axis of Mariana Trough

Total platinum-group elements （PGEs） abundances in basalts from the spreading axis of Mariana Trough ranged from 0.418 × 10^9 to 1. 022 × 10^-9, and primitive mantle-normalized PGE patterns are of positive slope showing the relative enrichment of PPGE （ platinum, palladium, rhodium） and gold relative to IPGE. Compared with other mantle-originated rocks, these basalts have lower PGE contents and wider ranges of primitive mantle-normalized ratios of palladium content to iridium one, palladium content to platinum one and palladium content to gold one exhibiting relative platinum and iridium depletion. Characteristics of PGE patterns indicated that the studied Mariana Trough basalts originated from low partial melting, and the MORB mantle beneath the spreading center had been contaminated by the are-island mantle. In the aspect of trace elements, Mariana Trough basalts showed the enrichment of LILE, lead and LREE, indicating that they had been influenced by subduetion compositions. All these demonstrated that Mariana Trough basalts are products of partial melting from a mixed mantle （ the contamination of MORB mantle by are-island mantle）.

An h-Adaptivity DG Method on Locally Curved Tetrahedral Mesh for Solving Compressible Flows

For the numerical simulation of compressible flows,normally different mesh sizes are expected in different regions.For example,smaller mesh sizes are required to improve the local numerical resolution in the regions where the physical variables vary violently(for example,near the shock waves or in the boundary layers)and larger elements are expected for the regions where the solution is smooth.h-adaptive mesh has been widely used for complex flows.However,there are two difficulties when employing h-adaptivity for high-order discontinuous Galerkin(DG)methods.First,locally curved elements are required to precisely match the solid boundary,which significantly increases the difficulty to conduct the"refining"and"coarsening"operations since the curved information has to be maintained.Second,h-adaptivity could break the partition balancing,which would significantly affect the efficiency of parallel computing.In this paper,a robust and automatic h-adaptive method is developed for high-order DG methods on locally curved tetrahedral mesh,for which the curved geometries are maintained during the h-adaptivity.Furthermore,the reallocating and rebalancing of the computational loads on parallel clusters are conducted to maintain the parallel efficiency.Numerical results indicate that the introduced h-adaptive method is able to generate more reasonable mesh according to the structure of flow-fields.

Expression of Hepatitis B Surface Antigen Gene in Ginseng Cells

The recombinant plasmid pBIBSa containing the HBsAg DNA fragment was transferred into Agrobacterium tumefaciens strain LBA4404 directly. Ginseng cells were transfected with A. tumefaciens carrying pBIBSa and the ginseng cell lines carrying HBsAg-S gene were obtained. The presence of target gene in the transfect cells was confirmed by PCR and RT-PCR. A clear band at the site of 700 bp was observed by agarose electrophoresis analysis of the samples containing the target gene. HBsAg expressed by the transgenic ginseng cells was detected by Western blot. Maximum expression levels of 184 ng HBsAg/g FW and 0. 009% of the total soluble proteins were observed by ELISA. HBsAg in ginseng cells was located both on the cell membrane and in the nuclei.

猪肉及制品中HEV、PEDV和PDCoV三重qPCR方法的建立与应用

人兽共患病引发的动物源性食品安全事件频发,为从食品原料源头上控制和保障其食用安全,控制猪肉及其制品消费成本,本研究构建了可同时检测猪肉及制品中戊型肝炎病毒(Hepatitis E virus,HEV)、猪流行性腹泻病毒(Porcine epidemic diarrhea virus,PEDV)和猪δ冠状病毒(Porcine delta corona virus,PDCoV)三重实时荧光定量PCR(Real-time Quantitative PCR,qPCR)方法。结果表明,三重qPCR方法只能扩增出3种目的病毒的特异性基因片段,特异性好;对HEV、PEDV和PDCoV三种病毒的最低检测限分别为6.02、6.98、6.92 copies/μL;组内和组间变异系数(CV%)在0.10%~3.00%之间,重复性好。将所建立方法应用于248份出口猪肉及制品和282份生猪粪拭子的检测,同时以相应病毒标准检测方法进行平行检测,结果显示猪肉及制品中三种病毒的检出率均为0%,与标准方法检测结果一致。生猪粪拭子中,该方法对PEDV、PDCoV和HEV三种病毒的检出率分别为1.06%、3.19%、0.35%,标准方法检出率分别为1.06%、3.19%、0%。研究表明,建立的三重qPCR检测方法能准确快速地检测猪肉及制品或生猪样品中三种病毒,为保障生鲜猪肉及其制品市场流通和阻断病毒食源性传播提供技术支持。

SARS-CoV-2 Omicron变异株多重微滴式数字PCR定量方法的建立及应用

【目的】为建立精准、高效的多重微滴式数字PCR(droplet digital PCR,ddPCR)定量分析检测方法,开发可同时鉴别新型冠状病毒(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)ORF1ab基因、N基因、E基因以及Omicron变异株S基因的检测体系,提高病毒性传染疾病的诊断效率及传播风险监测能力。【方法】通过筛选保守基因序列并设计特异性引物与探针,优化反应体系和扩增程序,对该方法的特异性、灵敏度及稳定性进行评价。以临床样本为实验材料,利用建立的ddPCR方法进行检测和验证,确定阳性检出率。【结果】多重ddPCR反应体系中,各对引物探针对目的片段均能有效扩增,SARS-CoV-2 ORF1ab基因、N基因、E基因以及Omicron变异株S基因灵敏度检测下限分别为0.59、0.68、1.44、1.03 copies/μL。在20份临床样本的核酸检测中,共检出16份阳性样本,阳性率达80%(16/20),经荧光定量PCR方法复测符合率一致。【结论】研究建立的多重ddPCR方法特异性强、灵敏度高,可实现对临床样本中微量新冠病毒的精确定量检测。

杨树KT、HAK、KUP基因家族鉴定及钾肥处理对杨树生长的影响

KT、HAK、KUP基因家族是植物进行K^(+)转运的最大蛋白系统。以毛果杨(Populus trichocarpa Torr.&Gray)全基因组数据为基础,利用生物信息学方法对杨树KT、HAK、KUP家族进行了全基因组鉴定,并在毛果杨全基因组中鉴定出20个KT、HAK、KUP家族成员。理化性质预测分析表明:KT、HAK、KUP基因家族成员均为疏水性蛋白,等电点在5.30~9.16;亚细胞定位预测显示家族成员蛋白集中在细胞质膜上。应用拟南芥和杨树构建系统进化树显示,KT、HAK、KUP基因家族可分为5个亚家族。基因结构及基序(motif)分析表明,KT、HAK、KUP基因进化过程相对保守。顺式作用元件分析表明,KT、HAK、KUP基因家族成员含有诸多与激素、逆境胁迫的响应元件。杨树不同钾离子浓度处理下,植株的净生长情况呈现了显著的差异,说明钾元素对杨树生长影响较大。

后牙高嵌体和[牙合]贴面修复的4年临床随访

目的:对比后牙高嵌体和[牙合]贴面修复体在不同性别、不同牙位、活髓牙和根管治疗牙上的4年临床成功率,探讨与全冠对比这种修复方式的优劣及更细化的适应证。方法:对2016—2019年由同一位术者诊治的共102位患者的124颗患牙进行前磨牙及磨牙计算机辅助设计/计算机辅助制造(computer aided design/computer aided manufacturing,CAD/CAM)二硅酸锂增强玻璃陶瓷高嵌体或者[牙合]贴面修复,其中活髓牙43颗,根管治疗牙81颗,咬合面修复体厚度为1.5 mm。在修复4年后进行回顾性调查,记录修复体生存率、修复体失败原因、患者满意率,比较活髓牙和根管治疗牙之间、修复牙位之间的修复体生存率。结果:活髓牙和剩余牙体组织较多的根管治疗牙修复4年后的生存率分别为95.5%和90.0%,平均生存率为91.9%。活髓牙的生存率高于根管治疗牙,但是差异无统计学意义,牙位之间生存率差异无统计学意义。失败原因有修复体崩瓷或折裂、修复体脱落、基牙劈裂、邻接触点下方继发龋,以及邻接触点松弛导致食物嵌塞等。患者总体满意率为91.5%。结论:玻璃陶瓷高嵌体和[牙合]贴面的4年生存率低于全冠修复体,并发症多于单冠修复体,应根据基牙牙髓活力和牙体组织剩余量来慎重选择其适应证,牙体组织剩余过少时最好选择桩核冠来进行修复,应保证修复体充分强度和厚度,预防食物嵌塞的发生,由于基牙预备量少,有对牙髓和牙周组织刺激小等优点,可推荐为试用修复方式。

枸杞LbaHY5基因克隆、亚细胞定位及表达分析

为研究枸杞LbaHY5基因的性质及功能,探明LbaHY5在枸杞果实发育中的作用,以宁夏枸杞宁杞1号为试材,采用生物信息学、亚细胞定位及qRT-PCR等方法对LbaHY5的结构和功能进行初步分析,结果表明:LbaHY5开放阅读框全长为483 bp,编码160个氨基酸,分子质量为17.52 ku,等电点为9.69,属于亲水性蛋白。保守结构和多序列比对分析显示,LbaHY5蛋白含有bZIP结构域,属于bZIP家族成员。进化树分析表明,枸杞LbaHY5蛋白与茄科植物如番茄、马铃薯等的HY5蛋白高度同源。此外,启动子分析表明,该基因启动子区域富含多种功能元件,这些元件分别与光信号、激素信号以及非生物胁迫应答等过程相关。亚细胞定位结果显示,LbaHY5蛋白定位在细胞核上。qRT-PCR检测发现,LbaHY5基因在花中表达量最高,茎中最低,且在果实发育时期表达量呈现逐渐上升趋势。研究表明LbaHY5可能参与枸杞花器官和果实生长发育。

猫犬主要过敏原蛋白的最新研究进展

猫犬过敏原可引发症状严重程度不一的过敏反应,诱发人类鼻炎和哮喘等,危害严重。在犬猫的皮屑、毛发、唾液、舌下腺等提取物中发现有多种致敏原。在很多公共场所(如医院、学校、办公室等)检测到的过敏原浓度足以引发过敏性疾病或者使症状加重,这些症状困扰着爱猫犬人士。目前,针对猫犬过敏最有效的治疗方法依然是过敏原特异性免疫疗法。本综述主要对当前犬猫过敏原的种类、异源表达、治疗方法的研究进展进行总结,并对过敏制剂的应用进行了展望,这为解决犬猫过敏症这一难题提供了新的思路。

台风“艾克”(2008)的海面风场模型研究

台风风场模拟的准确性对台风风场后报工作具有重要意义,目前通过参数模型构建台风边界层的海面风场是较快速且常用的方法之一。以2008年侵入墨西哥湾的大西洋第8号台风“艾克”为例,选取多种参数模型对比研究台风风场模拟的效果。实验结果表明,台风风场模型的选择对台风风场模拟效果具有显著影响。采用Jelesnianski-1风廓线模型即可较好地再现“艾克”台风风场的时空特征;此外,具有可变系数的Holland等气压模型风场和Miller等风廓线模型风场则具有较好的适用性,通过调整可变系数使得参数风场的风廓线贴合实际台风案例。整体而言,基于理想模型的参数风场能基本反映台风核心区域的海面风场特征,但对外围背景风场模拟效果不甚理想,而分析及再分析风场数据则能较好地反映台风外围的背景风场,因此采用参数风场与分析及再分析风场融合的方式构建台风风场,可显著提高台风“艾克”风场的数值模拟效果。

Beijing's Rapidly Expanding Highway Network

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