Insights into sensitizing and eliciting capacity of gastric and gastrointestinal digestion products of shrimp(Penaeus vannamei)proteins in BALB/c mice

Shrimp(Penaeus vannamei)proteins have been shown an allergenic potential;however,little information is available on the sensitizing and eliciting capacity of shrimp protein digestion products.In this study,a BALB/c mice model was used to explore the allergenicity of shrimp protein sample(SPS)and their gastric and gastrointestinal digestion products(GDS/GIDS).As compared with the SPS groups,the GDS/GIDS groups caused lower specific immunoglobulins(Ig E/Ig G1)levels(P<0.05),but higher than the control groups,indicating that the digestion products sensitized the mice.Meanwhile,spleen index,mouse mast cell protease-1(m MCP-1)concentration and proportion of degranulated mast cells were significantly reduced in the GDS/GIDS groups(P<0.05);simultaneously,allergic symptoms,vascular permeability and histopathological changes of tissues were alleviated.Nevertheless,the allergenicity of digestion products cannot be eliminated and still cause systemic allergic reactions in mice.The study showed that the digestion products of shrimp still had high sensitizing and eliciting capacity.

菌中之冠——银耳

银耳原产中国,可药食两用,历来深受人们喜爱,素有菌中之冠的美誉。论文以拟人化手法通过一场“黄白”银耳的庭审官司,悬念丛生地展开故事情节,形象生动地科普了银耳的外观、生活环境、栽培技术、功能应用以及与香灰菌的“伴生”关系等内容,并及时制止了一起“假燕窝”事件、当庭教育了造假者,以维护银耳世界的公平和良性竞争环境。旨在传播科学知识,弘扬科学精神,培养学生的职业道德观和社会责任感。

Ginsenoside Rc:A potential intervention agent for metabolic syndrome

Ginsenoside Rc,a dammarane-type tetracyclic triterpenoid saponin primarily derived from Panax ginseng,has garnered significant attention due to its diverse pharmacological properties.This review outlined the sources,putative biosynthetic pathways,extraction,and quantification techniques,as well as the pharmacokinetic properties of ginsenoside Rc.Furthermore,this study explored the pharmacological effects of ginsenoside Rc against metabolic syndrome(MetS)across various phenotypes including obesity,diabetes,atherosclerosis,non-alcoholic fatty liver disease,and osteoarthritis.It also highlighted the impact of ginsenoside Rc on multiple associated signaling molecules.In conclusion,the anti-MetS effect of ginsenoside Rc is characterized by its influence on multiple organs,multiple targets,and multiple ways.Although clinical investigations regarding the effects of ginsenoside Rc on MetS are limited,its proven safety and tolerability suggest its potential as an effective treatment option.

医学图像运动伪影校正的实验课程设计

医学图像处理是生物医学工程本科专业的一门重要课程,它主要利用数学、计算机科学和信息学等工具对医学成像设备产生的医学图像进行处理和加工,已成为医学研究、临床疾病诊断中一个不可或缺的工具和技术手段。但是在实际教学中,如何有效设计医学图像处理实验课程,培养学生发现问题和解决问题的能力,使学生将理论知识应用到临床实践当中面临巨大的挑战。图像退化与复原是医学图像处理中的重要内容,本实验课程围绕医学图像退化及复原中的运动伪影校正这一关键问题,以临床磁共振成像图像为数据来源,进行系统实验课程设计,通过该实验课程的学习,学生不但理解了图像退化及复原原理,掌握医学图像信息处理技能,还提高了设计实验、分析问题解决问题的能力,真正做到理论与临床实践相结合。

Ionic liquids for high performance lithium metal batteries

The pursuit of high energy density has promoted the development of high-performance lithium metal batteries.However,it faces a serious security problem.Ionic liquids have attracted great attention due to their high ionic conductivity,non-flammability,and the properties of promoting the formation of stable SEI films.Deeply understanding the problems existing in lithium metal batteries and the role of ionic liquids in them is of great significance for improving the performance of lithium metal batteries.This article reviews the effects of the molecular structure of ionic liquids on ionic conductivity,Li^(+)ion transference number,electrochemical stability window,and lithium metal anode/electrolyte interface,as well as the application of ionic liquids in Li-high voltage cathode batteries,Li-O_(2) batteries and Li-S batteries.The molecular design,composition and polymerization will be the main strategies for the future development of ionic liquid-based electrolytes for high performance lithium metal battery.

Organic anion transporters also mediate the drug–drug interaction between imipenem and cilastatin

This study aimed to clarify that organic anion transporters(OATs)mediate the drug–drug interaction(DDI)between imipenem and cilastatin.After co-administration with imipenem,the plasma concentrations and the plasma concentration-time curve(AUC)of cilastatin were significantly increased,while renal clearance and cumulative urinary excretion of cilastatin were decreased.At the same time,imipenem significantly inhibited the uptake of cilastatin in rat kidney slices and in human OAT1(hOAT1)-HEK293 and human OAT3(hOAT3)-HEK293 cells.Probenecid,p-aminohippurate,and benzylpenicillin inhibited the uptake of imipenem and cilastatin in rat kidney slices and in hOAT1-and hOAT3-HEK 293 cells,respectively.The uptakes of imipenem and cilastatin in hOAT1-and hOAT3-HEK 293 cells were significantly higher than that in mock-HEK-293 cells.Moreover,the K m values of cilastatin were increased in the presence of imipenem with unchanged V max,indicating that imipenem inhibited the uptake of cilastatin in a competitive manner.When imipenem and cilastatin were co-administered,the level of imipenem was higher compared with imipenem alone both in vivo and in vitro.But,cilastatin significantly inhibited the uptake of imipenem when dehydropeptidase-1(DPEP1)was silenced by RNAi technology in hOAT1-and hOAT3-HEK 293 cells.In conclusion,imipenem and cilastatin are the substrates of OAT1 and OAT3.OAT1 and OAT3 mediate the DDI between imipenem and cilastatin.Meanwhile,cilastatin also reduces the hydrolysis of imipenem by inhibiting the uptake of imipenem mediated by OAT1 and OAT3 in the kidney as a complement.

Operational procedures of auricular point sticking technology

As an external treatment technique of traditional Chinese medicine(TCM),auricular point sticking,which is rooted in holographic biology theory and TCM viscera and meridian theory,is a safe and effective treatment method.This article introduces the technology overview and development process.The auricular point sticking technique for constipation is taken as an example to specify the basic requirements,assessment,operational points,acupoint selection and matters needing attention during the implementation of the auricular acupressure technique,providing a reference for the operating procedures of this technique in the clinical treatment of other diseases such as insomnia,diarrhea,colds,hypertension,headache,and dysmenorrhea.

石墨烯结构的二维光子晶体禁带特性研究

本文设计了圆形、六边形两种散射元并引用二维石墨烯的蜂窝状结构,基于对光子晶体禁带的研究,利用平面波展开法,对这二种散射元构建的蜂窝状光子晶体的禁带特性进行模拟计算。分别得到了在TE和TM两种电磁场模式下光子晶体的禁带宽度,对相对禁带宽度关于散射元结构参数变化的关系做了分析,依据相对禁带宽度的大小,得到了相对禁带最大的模型。

Piperacillin enhances the inhibitory effect of tazobactam on β-lactamase through inhibition of organic anion transporter 1/3 in rats

To assess the mechanism of the pharmacokinetic interaction between piperacillin and tazobactam,renal excretion and pharmacokinetic studies of piperacillin/tazobactam were investigated in normal and bacteremia rats.A bacteremia model was established to investigate the pharmacokinetic properties of piperacillin and tazobactam under different conditions.Renal slices were taken to examine the uptake of piperacillin and tazobactam.Pharmacokinetic studies ofβ-lactamase in rats were performed to study the contribution of rOat1/3 to the inhibition of tazobactam onβ-lactamase.The AUC(from 2.93±0.58 to 6.52±1.44 mg·min/ml)and the plasma clearance(CL P)(from 2.41±1.20 to 0.961±0.212 ml/min/kg)of tazobactam were both altered after the intravenous coadministration of piperacillin and tazobactam in the bacteremia rats.The renal clearance(CL R)of tazobactam decreased from 1.30±0.50 to 0.361±0.043 ml/min/kg.In summary,there was a beneficial interaction between piperacillin and tazobactam mediated by rOat1 and rOat3.Piperacillin enhances the inhibitory effect of tazobactam onβ-lactamase through the inhibition of rOat1 and rOat3 in rats.The contribution rate of rOat1/3 for the synergistic effect was 20%when the two drugs were coadministered.

The transporters of intestinal tract and techniques applied to evaluate interactions between drugs and transporters

Most drug products on the global pharmaceutical market are administered orally.The absorption of oral drug in the intestine is an important factor to determine the drug bioavailability.There are many intestinal transporters expressed on the small intestine and the transporters can be classified into two major families,SLC family and ABC family.They mediate drug absorption,distribution,excretion and drugedrug interaction.Understanding the transport mechanism can improve the effectivity and safety of drug and guide clinical rational use of drugs.The roles of drug transporters can be assessed in vitro and in vivo,using techniques spanning from cellular expression systems to gene knockout animals.The purposes of this article were to introduce the main transporters in the intestinal tract,to explain the transport mechanism and to compare the limitations and applications of techniques used to evaluate interactions of drugs and transporters.

Device design based on the covalent homocouplingof porphine molecules

Porphine has a great potential application in molecular electronic devices.In this work,based on the density functional theory(DFT)and combining with nonequilibrium Green's function(NEGF),we study the transport properties of the molecular devices constructed by the covalent homocoupling of porphine molecules conjunction with zigzag graphene nanoribbons electrodes.We find that different couple phases bring remarkable differences in the transport properties.Different coupling phases have different application prospects.We analyze and discuss the differences in transport properties through the molecular energy spectrum,electrostatic difference potential,local density of states(LDOS),and transmission pathway.The results are of great significance for the design of porphine molecular devices in the future.

Potassium transporter OsHAK9 regulates seed germination under salt stress by preventing gibberellin degradation through mediating OsGA2ox7 in rice

Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9.Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress.OsHAK9 is highly expressed in germinating seed embryos.Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K^(+)efflux in salt-exposed germinating seeds for the balance of K^(+)/Na^(+).Disruption of OsHAK9 significantly reduced gibberellin 4(GA4)levels,and the germination defective phenotype of oshak9a was partly rescued by exogenous GA_(3)treatment under salt stress.RNA sequencing(RNA-seq)and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress,and the expression of OsGA2ox7 was significantly inhibited by salt stress.Null mutants of OsGA2ox7 created using clustered,regularly interspaced,short palindromic repeat(CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress.Overall,our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7,which provides a novel clue about the relationship between GA and OsHAKs in rice.

Hexamerin and allergen are required for female reproduction in the American cockroach,Periplaneta americana

Reproduction is of great importance for the continuation of the species.In insects,the fat body is the major tissue for nutrient storage and involved in vitellogenesis,which is essential for female reproduction.Here,2 proteins,hexamerin and allergen,were separated from the fat bodies of adult female American cockroaches(Periplaneta americana)and identified as storage proteins,encoding for 733 amino acids with molecular weight of 87.88 kDa and 686 amino acids with molecular weight of 82.18 kDa,respectively.The encoding genes of these 2 storage proteins are mainly expressed in the fat body.RNA interference-mediated knockdown of Hexamerin and Allergen in the early stage of the first reproductive cycle in females suppressed vitellogenesis and ovarian maturation,indicating that these storage proteins are involved in controlling reproduction.Importantly,the expression of Hexamerin and Allergen was repressed by knockdown of the juvenile hormone(JH)receptor gene Met and the primary response gene Kr-h1,and was induced by methoprene,a JH analog,in both in vivo and in vitro experiments.Altogether,we have determined that hexamerin and allergen are identified as storage proteins and play an important role in promoting female reproduction in the American cockroach.The expression of their encoding genes is induced by JH signaling.Our data reveal a novel mechanism by which hexamerin and allergen are necessary for JH-stimulated female reproduction.

Optimizing depth of field in 3D light-field display by analyzing and controlling light-beam divergence angle

A concept of divergence angle of light beams(DALB)is proposed to analyze the depth of field(DOF)of a 3D light-field display system.The mathematical model between DOF and DALB is established,and the conclusion that DOF and DALB are inversely proportional is drawn.To reduce DALB and generate clear depth perception,a triple composite aspheric lens structure with a viewing angle of 100°is designed and experimentally demonstrated.The DALB-constrained 3D light-field display system significantly improves the clarity of 3D images and also performs well in imaging at a 3D scene with a DOF over 30 cm.

北京大学重离子物理研究所40年发展历程

北京大学重离子物理研究所是在北京大学原技术物理系的基础上发展起来的.北京大学技术物理系成立于1955年(初期称物理研究室),是我国第一个核科学研究和人才培养基地,几十年来为国家培养了5000多名核科学技术人才.20世纪80年代初,针对当时核科学与技术的发展形势,北京大学酝酿成立重离子物理研究所.

陈佳洱与北京大学重离子物理研究所的粒子加速器研究

陈佳洱是我国著名的加速器物理学家.1958年,他带领年轻教师和学生在北京大学技术物理系建成了我国第一台30 MeV电子感应加速器,并于次年调试出束.20世纪60年代,在英国访问工作期间,他在国际上首次提出了诊断等时性回旋加速器越隙共振的实验判据,并发展了用可控的局域性一次谐波有效地抑制越隙共振振幅增长的方法.

直流-射频超导光阴极电子枪

直流-射频超导(direct current-superconducting radio frequency,DC-SRF)光阴极电子枪是由北京大学射频超导加速器实验室提出并发展的一种连续波电子源,可产生MHz及以上重复频率、皮秒至亚皮秒脉冲、Me V能量的电子束.作为一类重要的超导型光阴极电子枪,DC-SRF将具有高量子效率的半导体光阴极与射频超导加速腔分离,成功地解决了二者之间的兼容问题,并具有结构紧凑、暗电流低等优点.DC-SRF光阴极电子枪的研发经历了样机、DC-SRF-I及DC-SRF-II三个阶段,其中,DC-SRF-I于2014年实现稳定载束运行,并开展了系列应用实验;DCSRF-II于2021年建成,2022年实现100 p C束团电荷量、1 MHz重复频率的连续波模式运行,暗电流小于1 pA,归一化发射度达到亚mm-mrad级,综合性能指标处于领先地位.本文总结DC-SRF电子枪的研究工作,主要内容包括DCSRF-I电子枪、DC-SRF-II电子枪、光阴极与驱动激光等.

气道黏液栓对支气管哮喘患者的影响及管理要点

目的探讨气道黏液栓对支气管哮喘(简称哮喘)患者的影响及管理要点。方法本研究为横断面研究。根据纳入及排除标准,选取2020年1月至2022年6月在北京大学第三医院门诊就诊,确诊哮喘并进行胸部CT检查的患者100例,收集患者病史和一般资料、胸部CT结果、肺功能、呼出气一氧化氮(FeNO)测定、血常规、过敏原总IgE、烟曲霉M3过敏原特异性IgE抗体检测结果等临床资料,根据胸部CT结果将哮喘患者分为有黏液栓组和无黏液栓组,统计气道黏液栓的分布和基于支气管肺段的黏液栓评分,分析气道黏液栓和临床病史、哮喘急性发作、肺功能[包括支气管舒张试验前后用力肺活量占预计值的百分比(FVC%预计值)、第1秒用力呼气容积占预计值的百分比(FEV_(1)%预计值)、FEV_(1)/FVC、呼气峰值流量占预计值的百分比(PEF%预计值)、最大呼气中期流量(MMEF)及剩余25%、50%、75%肺活量时的最大呼气流量占预计值的百分比(MMEF%预计值、MEF_(25)%预计值、MEF_(50)%预计值、MEF_(75)%预计值)]、FeNO、外周血嗜酸性粒细胞(Eos)数量之间的关系,通过logistic回归模型分析气道黏液栓是否是哮喘急性发作的危险因素,并探讨对应的管理策略。结果100例哮喘患者中有黏液栓组24例,无黏液栓组76例。黏液栓组气道黏液栓的分布以双下肺多见(左肺下叶30.53%、左肺上叶9.16%、右肺下叶29.01%、右肺中叶14.50%、右肺上叶16.80%),黏液栓评分(4.42±3.12)分;体重指数(BMI)、入组前1年内因哮喘急性发作就医次数、FeNO、外周血Eos均显著高于无黏液栓组[(24.95±4.34)比(23.22±2.91)kg/m^(2)、0(0,1)比0(0,0)次、97(37,169)比31(18,59)ppb(1 ppb=1×10^(-9))、0.41(0.15,0.70)比0.18(0.09,0.37)×10^(9)/L](均P<0.05);FVC%预计值、FEV_(1)%预计值、FEV_(1)/FVC、PEF%预计值、MEF_(50)%预计值、MEF_(25)%预计值、MMEF%预计值、MEF_(75)%预计值均显著低于无黏液栓组[(87.49±19.32)%比(97.34±14.24)%、(76.49±19.58)%比(91.07±18.33)%、(72.44±10.91)%比(79.48±8.13)%、(82.36±24.46)%比(93.83±18.27)%、(53.03±24.81)%比(75.75±27.15)%、(46.47±22.92)%比(64.09±25.90)%、(50.28±23.73)%比(74.53±26.80)%、(71.30±27.55)%比(89.92±26.82)%](均P<0.05);气道黏液栓评分和患者体重、入组时外周血Eos数量均呈正相关(r=0.413、0.478;均P<0.05),和FVC%预计值、FEV_(1)%预计值呈负相关(r=-0.576、-0.465;均P<0.05)。Logistic回归分析显示,气道黏液栓评分是哮喘急性发作的危险因素(OR=1.269,95%CI:1.031~1.562;P=0.024)。结论哮喘患者具有较高的气道黏液栓发生率,并与Eos炎症水平、体型相关。气道黏液栓可促进患者气流阻塞、哮喘急性发作。临床可针对气道黏液栓制定相应哮喘管理策略,延缓哮喘病情进展,减少急性发作次数。

Developmental toxicity and programming alterations of multiple organs in offspring induced by medication during pregnancy

Medication during pregnancy is widespread,but there are few reports on its fetal safety.Recent studies suggest that medication during pregnancy can affect fetal morphological and functional development through multiple pathways,multiple organs,and multiple targets.Its mechanisms involve direct ways such as oxidative stress,epigenetic modification,and metabolic activation,and it may also be indirectly caused by placental dysfunction.Further studies have found that medication during pregnancy may also indirectly lead to multi-organ developmental programming,functional homeostasis changes,and susceptibility to related diseases in offspring by inducing fetal intrauterine exposure to too high or too low levels of maternal-derived glucocorticoids.The organ developmental toxicity and programming alterations caused by medication during pregnancy may also have gender differences and multi-generational genetic effects mediated by abnormal epigenetic modification.Combined with the latest research results of our laboratory,this paper reviews the latest research progress on the developmental toxicity and functional programming alterations of multiple organs in offspring induced by medication during pregnancy,which can provide a theoretical and experimental basis for rational medication during pregnancy and effective prevention and treatment of drug-related multiple fetal-originated diseases.

Gestational dexamethasone exposure impacts hippocampal excitatory synaptic transmission and learning and memory function with transgenerational effects

The formation of learning and memory is regulated by synaptic plasticity in hippocampal neurons.Here we explored how gestational exposure to dexamethasone,a synthetic glucocorticoid commonly used in clinical practice,has lasting effects on offspring's learning and memory.Adult offspring rats of prenatal dexamethasone exposure(PDE)displayed significant impairments in novelty recognition and spatial learning memory,with some phenotypes maintained transgenerationally.PDE impaired synaptic transmission of hippocampal excitatory neurons in offspring of F1 to F3 generations,and abnormalities of neurotransmitters and receptors would impair synaptic plasticity and lead to impaired learning and memory,but these changes failed to carry over to offspring of F5 and F7 generations.Mechanistically,altered hippocampal miR-133a-3p-SIRT1-CDK5-NR2B signaling axis in PDE multigeneration caused inhibition of excitatory synaptic transmission,which might be related to oocyte-specific high expression and transmission of miR-133a-3p.Together,PDE affects hippocampal excitatory synaptic transmission,with lasting consequences across generations,and CDK5 in offspring's peripheral blood might be used as an early-warning marker for fetal-originated learning and memory impairment.