六价铬激活mTOR蛋白诱导大鼠急性肾损伤

目的探讨哺乳动物雷帕霉素靶蛋白(mTOR)在六价铬[Cr(Ⅵ)]所致大鼠急性肾损伤(AKI)中的作用。方法42只雄性SD大鼠随机分为正常对照组(单次ip给予生理盐水)、不同剂量Cr(Ⅵ)处理组〔单次ip给予Cr(Ⅵ)5或10 mg·kg-1〕、雷帕霉素(Rap)干预组〔隔日1次(共4次)ip给予Rap 2 mg·kg-1,而后ip给予Cr(Ⅵ)5或10 mg·kg-1〕和NAC干预组〔连续3 d,每日1次ip NAC 300 mg·kg-1,而后ip给予Cr(Ⅵ)5或10 mg·kg-1〕。Cr(Ⅵ)处理48 h后,分别称取大鼠体质量和肾质量,计算肾系数;HE染色后,在显微镜下采用AutoCAD软件计算肾小管损伤面积百分比;ELISA法检测血清肌酐(Scr)和尿中性粒细胞明胶酶相关脂质运载蛋白(NGAL)水平;紫外分光光度法检测肾组织中谷胱甘肽(GSH)和丙二醛(MDA)水平;Western印迹法检测肾组织中磷酸化mTOR(p-mTOR)、磷酸化p70核糖体蛋白S6激酶(p-p70S6K)和活化的胱天蛋白酶3蛋白表达水平。结果与正常对照组相比,Cr(Ⅵ)10 mg·kg-1组大鼠肾质量和肾系数明显增加(P<0.05);Cr(VI)5和10 mg·kg-1组Scr、尿NGAL水平、肾小管损伤平均面积百分比和MDA含量明显升高(P<0.05),肾组织中p-mTOR、p-p70S6K和活化胱天蛋白酶3蛋白表达水平明显上调(P<0.05),GSH含量明显降低(P<0.05)。与同剂量Cr(Ⅵ)处理组相比,Rap或NAC干预组Scr、肾小管损伤面积百分比、肾组织p-mTOR、p-p70S6K和活化的胱天蛋白酶3表达水平均明显下调(P<0.05)。与NAC干预组比较,Rap干预组Scr、肾小管损伤平均面积百分比和活化的胱天蛋白酶3表达水平明显降低(P<0.05),而氧化应激标志物MDA水平无明显差异。结论Cr(Ⅵ)可诱导mTOR磷酸化激活导致AKI,mTOR抑制剂Rap可有效拮抗Cr(Ⅵ)引起的AKI。

Low dose bisphenol A impairs spermatogenesis by suppressing reproductive hormone production and promoting germ cell apoptosis in adult rats

Bisphenol A （BPA）, an estrogenic chemical, has been shown to reduce sperm count; however, the underlying mechanisms remain unknown. Herein, we show that oral administration of BPA （2 μg/kg） for consecutive 14 days in adult rats （BPA rats） significantly reduced the sperm count and the number of germ cells compared to controls. The serum levels of testosterone and follicle-stimulating hormone （FSH）, as well as the level of GnRH mRNA in BPA rats were lower than those of control rats. Testosterone treatment could partially rescue the reduction of germ cells in BPA rats. Notably, the number of apoptotic germ cells was significantly increased in BPA rats, which was insensitive to testosterone. Furthermore, the levels of Fas, FasL and caspase-3 mRNA in the testicle of BPA rats were increased in comparison with controls. These results indicate that exposure to a low dose of BPA impairs spermatogenesis through decreasing reproductive hormones and activating the Fas/FasL signaling pathway.

Effect of BaNH,CaNH,Mg3N2 on the activity of Co in NH3 decomposition catalysis

Development of active and non-noble metal-based catalyst for H2 production via NH3 decomposition is crucial for the implementation of NH3 as a H2 carrier.Co-based catalysts have received increasing attention because of its high intrinsic activity and moderate cost.In this work,we examined the effect of BaNH,CaNH and Mg3 N2 on the catalytic activity of Co in the NH3 decomposition reaction.The H2 formation rate ranks the order as Co-BaNH>Co-CaNH>Co-Mg3 N2≈Co/CNTs within a reaction temperature range of 300-550℃.It is worth pointing out that the H2 formation rate of Co-BaNH at 500℃reaches20 mmolH2 gcat-1 min-1,which is comparable to those of the active Ru/Al2 O3(ca.17 mmolH2 gcat-1 min1)and Ru/AC(21 mmolH2 gcat-1 min-1)catalysts under the similar reaction conditions.In-depth research shows that Co-BaNH exhibits an obviously higher intrinsic activity and much lower Ea(46.2 kJ mol-1)than other Co-based catalysts,suggesting that BaNH may play a different role from CaNH,Mg3 N2 and CNTs during the catalytic process.Combined results of XRD,Ar-TPD and XAS show that a[Co-N-Ba]-like intermediate species is likely formed at the interface of Co metal and BaNH,which may lead to a more energy-efficient reaction pathway than that of neat Co metal for NH3 decomposition.

Regulatory role of sorting nexin 5 in protein stability and vesicular targeting of vesicular acetylcholine transporter to synaptic vesicle-like vesicles in PC12 cells

Accurate targeting of vesicular acetylcholine transporter(VAChT)to synaptic vesicles(SVs)is indispensable for efficient cholinergic transmission.Previous studies have suggested that the dileucine motif within the C-terminus of the transporter is sufficient for its targeting to SVs.However,the cytosolic machinery underlying specific regulation of VAChT trafficking and targeting to SVs is still unclear.Here we used the C-terminus of VAChT as a bait in a yeast two-hybrid screen to identify sorting nexin 5(SNX5)as its novel interacting protein.SNX5 was detected in the SVs enriched LP2 subcellular fraction of rat brain homogenate and showed strong colocalization with VAChT in both brain sections and PC12 cells.Binding assays suggested that the C-terminal domain of VAChT can interact with both BAR and PX domain of SNX5.Depletion of SNX5 enhanced the degradation of VAChT and the process was mediated through the lysosomal pathway.More importantly,we found that,in PC12 cells,the depletion of SNX5 expression significantly decreased the synaptic vesicle-like vesicles(SVLVs)localization of VAChT.Therefore,the results suggest that SNX5 is a novel regulator for both stability and SV targeting of VAChT.

Underground location algorithm based on random forest and environmental factor compensation

Aiming at the poor location accuracy caused by the harsh and complex underground environment,long strip roadway,limited wireless transmission and sparse anchor nodes,an underground location algorithm based on random forest and compensation for environmental factors was proposed.Firstly,the underground wireless access point(AP)network model and tunnel environment were analyzed,and the fingerprint location algorithm was built.And then the Received Signal Strength(RSS)was analyzed by Kalman Filter algorithm in the offline sampling and real-time positioning stage.Meanwhile,the target speed constraint condition was introduced to reduce the error caused by environmental factors.The experimental results show that the proposed algorithm solves the problem of insufficient location accuracy and large fluctuation affected by environment when the anchor nodes are sparse.At the same time,the average location accuracy reaches three meters,which can satisfy the application of underground rescue,activity track playback,disaster monitoring and positioning.It has high application value in complex underground environment.

下调ALK2对人乳腺癌MDA-MB-468细胞增殖、侵袭和迁移能力的影响

目的:通过表达siALK2的重组腺病毒Ad-siALK2,下调人乳腺癌MDA-MB-468细胞ALK2的表达,研究其对MDA-MB-468细胞增殖、侵袭和迁移能力的影响。方法:以重组腺病毒Ad-siALK2感染MDA-MB-468细胞为实验组,空载病毒(RFP)作为感染对照,并设空白对照组,通过倒置荧光显微镜观察和RT-PCR检测病毒在MDA-MB-468细胞中的表达水平,通过MTT、平板集落形成、细胞划痕和Transwell侵袭实验检测细胞的增殖、集落形成、迁移及侵袭能力。结果:倒置荧光显微镜观察显示Ad-siALK2感染MDA-MB-468细胞的荧光效率高;RT-PCR证实Ad-siALK2感染的MDA-MB-468细胞ALK2的mRNA表达显著下降;MTT法、平板集落形成实验、细胞划痕实验及Transwell侵袭实验证实MDA-MB-468细胞Ad-siALK2组相比对照组细胞的增殖活力、集落形成率及划痕愈合率均显著降低(P<0.05),穿膜细胞数也明显减少(P<0.05)。结论:下调ALK2表达后可以在体外抑制人乳腺癌MDA-MB-468细胞的增殖、迁移与侵袭,为后续实验研究奠定了基础。

Luminal/extracellular domains of chimeric CI-M6PR-C proteins interfere with their retrograde endosome-to-TGN trafficking in the transient expression system

The membrane trafficking of cation-independent mannose 6-phosphate receptor（CI-M6PR） between the transGolgi network（TGN） and endosomal compartments is not only critical for maintaining lysosomal function but also a well-known event for understanding molecular and cellular mechanisms in retrograde endosome-to-TGN trafficking.Although it has been well established in literature that the C-terminus of bovine CI-M6PR determines its retrograde trafficking,it remains unclear whether the luminal domain of the protein plays a role on these sorting events.In this study,we found that partial deletion of luminal domain of human CI-M6PR mistargeted the mutant protein to nonTGN compartments.Moreover,replacing the luminal domain of both bovine and human CI-M6PR with that from irrelevant membrane proteins such as CD8 or Tac also altered the TGN targeting of the chimeric proteins.On the other hand,only short sequence from HA fused with the transmembrane domain and C-terminus of the receptor,HA-hCIM6PR-tail,resulted in its preferential targeting to TGN as for the full length receptor,strongly suggesting that sorting of the receptor may be influenced by luminal sequence.Furthermore,using this luminal truncated form of HA-hCIM6 PR as a model cargo,we found that the trafficking of the chimeric protein was regulated by the retromer complex through interacting with SNX5.In conclusion,our study strongly suggested that the disrupted luminal domain from hCI-M6PR or other irrelevant membrane proteins interfere with the process of membrane trafficking and TGN targeting of CI-M6PR.

Cartilage Repair by Joint Distraction and Motion Using an External Fixator for Massive Cartilage Defect

The objective of the present study was to investigate our novel methods for the repair of massive cartilage defects by joint distraction and motion using an external fixator. In this study, we used a rabbit model of massive articular cartilage defect in order to evaluate the effectiveness of using joint distraction and motion with a ring-type external fixator. This external fixator has a hinged joint with a center of rotation along the femoral transepicondylar axis, which allows the knee joint to freely flex and extend. Mesenchymal cells from bone marrow, induced by spongialization, were differentiated into mature chondrocytes and formed hyaline-like cartilage as a result of joint distraction and movement. The transplantation of autologous cells expanded from bone-marrow-derived mesenchymal cells, concentrated autologous bone marrow aspirate, and concentrated autologous peripheral blood cells were all effective in promoting cartilage repair. The quality of the cartilage after long-term joint distraction for 6 months was inferior to that after 12 weeks. In general, weight bearing on the regenerated cartilage promoted cartilage repair, although this effect differed based on when gradual weight bearing was begun. Specifically, gradual weight bearing beginning at 9 weeks produced superior results to that beginning at 6 weeks. Our methods provide an optimal environment for cartilage regeneration.

以岗位胜任力为导向的医学检验人才培养教学改革与实践

分析地方医学院校医学检验技术专业岗位胜任力培养中存在的主要问题,并对人才培养方案、协同育人机制、课程教学体系、考核评价方式进行改革和实践,初步构建以岗位胜任力为导向的医学检验人才培养模式,旨在切实提高医学检验人才的岗位胜任力。

临床血液学检验线上教学的探索与实践

临床血液学检验是医学检验技术专业的主干课程,教学任务是培养学生血液系统疾病的临床检验能力。疫情期间为保证线上教学质量,课程教学团队积极行动,在分析课程建设现状和学情的基础上,采用超星尔雅平台在线学习、钉钉直播、QQ平台发布资源和答疑等多种方式开展教学,同时还组织了小组学习、病例讨论等特色教学活动,并对线上教学管理和学业成绩评价方式进行改革。

Retrograde trafficking of VMAT2 and its role in protein stability in non-neuronal cells

Increasing evidence suggests that the impaired neuroprotection of vesicular monoamine transporter 2（VMAT2）contributes to the pathogenesis of Parkinson＇s disease.That has been linked to aberrant subcellular retrograde trafficking as strongly indicated by recent genomic studies on familial Parkinson＇s diseases.However,whether VMAT2 function is regulated by retrograde trafficking is unknown.By using biochemistry and cell biology approaches,we have shown that VMAT2 was stringently localized to the trans-Golgi network and underwent retrograde trafficking in non-neuronal cells.The transporter also interacted with the key component of retromer,Vps35,biochemically and subcellularly.Using specific siRNA,we further showed that Vps35 depletion altered subcellular localization of VMAT2.Moreover,siRNA-mediated Vps35 knockdown also decreased the stability of VMAT2 as demonstrated by the reduced half-life.Thus,our work suggested that altered vesicular trafficking of VMAT2 may play a vital role in neuroprotection of the transporter as well as in the pathogenesis of Parkinson＇s disease.

Distinctive roles of Rac1 and Rab29 in LRRK2 mediated membrane trafficking and neurite outgrowth

Parkinson＇s disease（PD） associated leucine-rich repeat kinase 2（LRRK2） mutants have shown pathogenic effects on a variety of subcellular processes. Two small GTPases Rac1 and Rab29 have been indicated as possible downstream effectors participating in LRRK2 signaling but their detail mechanisms remain unclear. In this study, we have used biochemical and cell biology approaches to address whether two GTPases interact with LRRK2 and hence function differently in LRRK2 mediated pathogenesis. Here we show that Rac1 and Rab29 specifically interact with LRRK2 with higher affinity for Rab29 and with different preference in functional domain binding. Mutant Rab29 but not Racl alters the endosome-to-TGN retrograde trafficking of a cargo protein cation-independent mannose-6-phosphate receptor（CI-M6 PR） and its stability. On the other hand, overexpressed wild type Rab29 but not Racl rescued the altered retrograde membrane trafficking induced by the pathogenic mutant LRRK2^（G2019 S）. Furthermore,both Rac1 and Rab29 rescued neurite shortening in differentiated SH-SY5 Y cells induced by LRRK2^（G2019 S）. Our study strongly suggests that Rac1 and Rab29 are involved in distinct functions as downstream effectors in LRRK2 signaling pathways.

Inhibitory role of peroxiredoxin 2 in LRRK2 kinase activity induced cellular pathogenesis

Parkinson’s disease(PD) is a major neurodegenerative disease. One of the known genetic contributors to PD pathogenesis is leucine-rich repeat kinase 2(LRRK2) whose mutations with elevated kinase activity could lead to both familial and sporadic PD. However, how the pathogenic kinase activity of LRRK2 is regulated remains largely unclear. Here we report that peroxiredoxin 2(Prx2) was identified as a novel interacting protein to LRRK2 with preferential expression in dopaminergic neurons over other Prx proteins. We also confirmed that Prx2 interacted with LRRK2 through its COR domain and its overexpression significantly decreased the kinase activity of mutant LRRK2. Functionally, overexpressed Prx2 rescued the transfected cells from LRRK2 mutant induced apoptotic processes. Importantly, overexpressed Prx2 reversed the altered subcellular distribution of cationindependent mannose 6-phosphate receptor(CI-M6 PR) induced by PD-mutant LRRK2. Our results suggest that,by interacting with LRRK2, Prx2 may play an inhibitory role in the LRRK2 mediated cellular toxicity in PD by inhibiting its kinase activity.

Comprehensive evaluation of an ionic liquid based deep purification process for NH_(3)-containing industrial gas

Ammonia(NH_(3))emission has caused serious environment issues and aroused worldwide concern.The emerging ionic liquid(IL)provides a greener way to efficiently capture NH_(3).This paper provides rigorous process simulation,optimization and assessment for a novel NH_(3)deep purification process using IL.The process was designed and investigated by simulation and optimization using ionic liquid[C_(4)im][NTF_(2)]as absorbent.Three objective functions,total purification cost(TPC),total process CO_(2)emission(TPCOE)and thermal efficiency(ηeff)were employed to optimize the absorption process.Process simulation and optimization results indicate that at same purification standard and recovery rate,the novel process can achieve lower cost and CO_(2)emission compared to benchmark process.After process optimization,the optimal functions can achieve 0.02726$/Nm~3(TPC),311.27 kg CO_(2)/hr(TP-COE),and 52.21%(ηeff)for enhanced process.Moreover,compared with conventional process,novel process could decrease over$3 million of purification cost and 10000 tons of CO_(2)emission during the life cycle.The results provide a novel strategy and guidance for deep purification of NH_(3)capture.

Node Search Contributions Based Long-Term Follow-Up Specific Individual Searching Model

In this paper,we introduce a long-term follow-up specific individual searching(SIS)model.This model introduces the concept of node search contributions by considering the characteristics of the network structure.A node search contribution indicates the ability of a certain node to correctly guide the search path and successfully complete an SIS.The influencing factors of node search contributions have three components:the individual influence index,attribute similarity,and node search willingness.On the basis of node search contributions and the PeopleRank idea,this paper proposes an SIS model based on node search contribution values and conducts comparison experiments with several mainstream SIS algorithms in three aspects:the search failure rate,the minimum number of search hops,and the search size.The experimental results verify the advanced nature and operability of the model proposed in this paper,which presents theoretical and practical significance to the quantitative study of the SIS process.

Extended culture of day 3 embryos improves live birth rate in in vitro fertilization-embryo transfer

To the Editor:Embryo development at the early cleavage stage is a complex and well-orchestrated biological process.During in vitro fertilization-embryo transfer(IVF-ET),embryos are routinely stratified according to morphological criteria and transferred on the morning of day 3 after fertilization.This stage of embryonic development is mainly regulated by maternal factors because the embryonic genome has not yet been fully activated.[1]Day 3 is a key period for embryos to accomplish embryonic genome activation(EGA).Embryos with higher developmental potential initiate EGA for subsequent development and implantation,while non-viable embryos undergo arrest.

儿童口腔感染美丽筒线虫1例

患儿,男,4岁,湖南怀化人2020年7月12日患儿刷牙时从口中吐出一条细长的虫体(图1),未见牙龈出血,遂将虫体置于纯净水中保存。7月13日至怀化市第一人民医院就诊,自述无任何不适.既往体健、无消化道疾病、无寄生虫病等病史。常居住于怀化市鹤城区,多与父母居住,偶于农村奶奶家居住.奶奶家常有鼠、蟑螂出没,无外地久居史;无饮生水、无生食昆虫、肉类、蔬菜的习惯,但有吸手指头的嗜好.

Design and Implementation of a Chinese Pulse Condition Acquisition System

Nowadays, with improvements in the quality of life, people are paying more attention to their health. Traditional Chinese medicine offers great advantages for daily care. In this paper, we present the development of a remote health care system, namely, Chinese Pulse Condition Acquisition System （CPCAS）, based on the principle of Chinese pulse diagnosis in Chinese medicine and a wireless sensor network. We designed a remote health care terminal with a mini-pulse collection bench to overcome the challenge of differences in pulse characters of different people. An effective measured pressure control algorithm is proposed to achieve a balance between control accuracy and control time. The special signal conditioning circuit showed good performance in analog pulse signal processing. We also performed significant research to address the challenges of symptom recognition. Other distinctive features of this system include the following： intelligent sensing, a wireless health care network, effective energy management, small size, lightweight, and the ability to be networked for remote management. In this paper, we have introduced the design and implementation of CPCAS. We also demonstrate the use of the system and give evaluations on this system by several experiments. Our results indicate that CPCAS has significant practical feasibility.

Mechanical properties and microstructure of multilayer graphene oxide cement mortar

This study reports on the effects of multilayer graphene oxide(MGO)on compressive strength,flexural strength,and microstructure of cement mortar.The cement mortar was prepared with type P.II.52.5 Portland cement,standard sand,and MGO.Four mixes were prepared with inclusion of MGO(0%,0.02%,0.04%,and 0.06%by weight of cement).The testing result shows that the compressive of GO-cement mortar increased by 4.84%–13.42%,and the flexural strength increased by 4.37%–8.28%at 3 d.GO-cement mortar’s compressive strength and flexural strength at 7 d increased by 3.84%–12.08%and 2.54%–13.43%,respectively.MGO made little contribution to the increases of compressive strength and flexural strength of cement mortar at 28 d.The results of X-ray diffraction(XRD),scanning electron microscope(SEM),and nitrogen(N2)adsorption/desorption tests show that the types of hydration products and crystal grain size did not change after adding MGO.Still,it can help to improve the microstructure of the cement mortar via regulating hydration products and can provide more condensed cores to accelerate hydration.Furthermore,the regulating action of MGO for the microstructure of cement mortar at an early age was better than that at 28 d.

Generation of CRISPR/Cas9-mediated lactoferrin-targeted mice by pronuclear injection of plasmid pX330

Lactoferrin is a member of the transferrin family of multifunctional iron binding glycoproteins.While numerous physiological functions have been described for lactoferrin,the mechanisms underlying these functions are not clear.To further study the functions and mechanisms of lactoferrin,we modified the lactoferrin promoter of mice using the CRISPR/Cas9 system to reduce or eliminate lactoferrin expression.Seven mice with lactoferrin promoter mutations were obtained with an efficiency of 24%(7/29)by injecting the plasmid pX330,expressing a small guide RNA and human codonoptimized SpCas9,into fertilized eggs of mice.Plasmid integration and off-targeting of pX330 were not detected.These results confirmed that pronuclear injection of a circular plasmid is a feasible and efficient method for targeted mutagenesis in mice.