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1.
INTRODUCTIONry-Aminobutyric acid (GABA) is the predomi-nant inhibitory neurotransmitter in the vertebratecentral nervous system (CNS)[1]. Whereas outsidethe CNS, many peripheral tissues have also beenfOund to have GABAergic system[2].The mammalian sperm acrosome reaction (AR)is a modified exocytotic event that is essential to thefertilization process[3]. Two main agOnists of AR,the zona pellucida glycoprotein ZP3[4] and proges-terone[5], have been identified in the oocyte vest-me…  相似文献   

2.
INTRODUCTIONAsaderivativeofvitaminA,RAcaninhibittheproliferati0nofmanymalignantcel1sallde1icitdifferentiationinsometumorce1lsI1-5].RecentstudieshaveshownthatRAmodu1atessynthesisofover4Oproteinsthroughitsnucleicrecept0r[6].Forinstance,RAinducesthesynthesis0ffibronectin(FN)incertaintumorcellsandactivatesthegenecodingfOrB1sllbunitoflaminin(LN)causingitsexpressi0n[7,8].FNandLN'areknownt0bethemostimportantcomponentsofnon-c0llageng1ycoproteinsintheextracellu1armatrixandareclose1yrelatedt…  相似文献   

3.
INTRoDUCTIONDuchenneandBeckermusculardystrophy(DMD,BMD)areX-linkedrecessivedisorders,affectingabout1in33OOlivebornmales[1].ThegenehasbeenlocatedatXp21byidentificationofunusualpatientswithcytogeneticallyvisibledeletionofXp21l2]orbalancedX:autosometranslocation[3].SubsequentlinkagestudiesusingrandomlyclonedDNAprobesfromthisregionconfirmedthelocalizationofthegenetoXp21[4-5].DeletionsoftheDMDgenein17%ofindividualswithDuchennemusculardystrophy(DMD)werefirstdetectedwiththesingle-copyD…  相似文献   

4.
Type 2 diabetes(T2D)is a chronic metabolic disease characterized by insulin resistance and hyperglycemia,which is ultimately linked to the loss of pancreaticβ-cells and their function[1].Understanding the pathological mechanisms ofβ-cell dysfunction in T2D may lead to development of new therapeutic approaches.Recently,compelling evidence suggests that members of the nuclear receptor 4A(NR4A)subgroup play a pivotal role inβ-cell loss[2].Nor1,also known as NR4A3,belongs to the NR4A subfamily,which also includes Nur77(NR4A1)and Nurr1(NR4A2),and is defined as a true orphan nuclear receptor with an unknown endogenous ligand or ligand independent[3].As a regulator of gene expression located in the nucleus,Nor1 exhibits tissue-specific expression,which selectively controls diverse biological processes,including cell proliferation,apoptosis,differentiation,immune homeostasis,and fuel utilization[4].Thus far,it was reported that Nor1 is involved in numerous pathologies such as cancer,inflammatory diseases,and Parkinson’s disease[4].  相似文献   

5.
Toll-like receptors(TLRs)are type I transmembrane proteins that are important components of innate immunity and play essential roles in inducing acquired immune responses[1].These proteins consist of three parts:the cytoplasmic domain,transmembrane domain,and extracellular domain.The extracellular domain is composed of 18–33 leucine-rich repeat(LRR)sequences that enable the host to specifically recognize pathogen-associated molecular patterns and are the core of TLR recognition ligands[2].The cytoplasmic domain is homologous with the interleukin 1 receptor(IL-1R)family and known as the Toll-IL-1 receptor homology domain,which is highly conserved and plays a key role in signal transduction[1].TLR3 recognizes viral dsRNA during immune protection from viruses[3].After the host is infected by a virus,the LRR region of TLR3 recognizes the viral dsRNA,and the Toll/IL-1 receptor(TIR)domain recruits the adaptor protein TIR domain-containing molecule 1(also known as TRIF)for signal cascade transmission[4].The activation of TLR3 finally leads to cytokine secretion,especially the production of type I interferon[4].Lamprey,the most primitive marine jawless vertebrate,is an ideal model for studying vertebrate embryo development,organ differentiation,and immune system evolution[5].Although jawless vertebrates contain three variable lymphocyte receptors,they have not been found to possess the recombinational antigen receptors shared by all jawed vertebrates[6].Compared with that in higher vertebrates,the mechanism of acquired immunity in lampreys is still not complete,and lampreys rely mainly on innate immunity to fight against pathogenic microorganisms.Although TLR3 has been extensively studied in jawed vertebrates,little is known about the molecular evolutionary history and expression patterns of TLR3 in jawless vertebrates.  相似文献   

6.
INTRODUCTIONLivercirrhosisisoftencomplicatedbyhyperdynamiccirculation,whichischaracterizedbyadecreaseinarterialbloodpressureandperipheralvascularresistanceandanincreaseincardiacoutputandsplanchnicbloodnow[1].Thesehaemodynamicdisturbancesareproposedtocontributetothedevelopmelltofportalhypertension,retentionofsodiumandwater,ascitesformationandcorrelatewithprognosisoflivercirrhosis[2].Ithasbeensuggestedthatprimaryarterialvasodilationmayinducethishyperdynamiccirculation[3].Buttheunderlyingmec…  相似文献   

7.
SSKOIDE 《Cell research》1997,7(1):51-59
INTRODUCTIONEpidermalgrowthfactor(EGF)wasinitiallyisolatedandpurifiedfromthesubmaxillarygland(SMG)ofmalemouse[1].Itisapolypeptidecomposedof53aminoacidresidues[2].Itinfluencescellproliferationanddifferentiationandmodulatesthegrowthanddevelopmentofmammalianorgans[3--7].AnoteworthyfindingisthatextirpationofmouseSMGresultsinamarkedreductionofserumEGFconcentrationassociatedwithanimpairedspermatogenesis[3].ThisfindingsuggeststhatEGFmayregulatespermproductionanddifferentiation.Inhumantest…  相似文献   

8.
Apocytochromec(Apocyt.c)istheheme-freeprecursorofcytochromec.Itissynthesizedinthecytosolandpost-translationallyimportedintomitochondriabyfollowingaquiteuniquepath-waycomparedtoothermitochondrialprecursorproteins[1].ItdoesnotpossessacleavableN-terminalpresequence,andneitheramembranepotentialnorATPisrequiredforitsimport[2].Further,noproteinaceouscomponentresponsibleforitsimporthaseverbeenidentified[3,4].Intheintermembranespaceapocyt.cisconvertedintoholocytochromecbycytochromechemelyase(CCHL)…  相似文献   

9.
10.
Ineukaryocyte,themitogen-activatedproteinkinases(MAPKs)playcriticalrolesinmanysignaltransductionprocesses[1].p38signalpathwayisanimportantbranchoftheMAPKs[2].Oneoftheprimaryfunctionsofp38medicatestheinflammatorysignalbyphosphorylatingATF[3].Itisknownthatinhibitingthep38activitycanblockthesignaltransductionofinflammationandsub-sequentlyalleviateinflammatoryresponse[4].Inrecentyears,severalresearchgroupshavetriedtousesomespecificinhibitorsofp38forclinictrial[5—7].IthasbeendemonstratedthatP…  相似文献   

11.
Fang L  Fang J  Chen CQ 《Cell research》2001,11(3):217-222
INTRODUCTIONTumor necrosis factor alpha (TNFa) is apleiotropic cytokine that is mainly produced by acti-vated macrophages and lymphocytes[1]. TNFa ini-tiates inflammatory, immune regulatory and patho-physiologic responses by binding to two distinct cellsurface receptors of TR55 (55 kDa) and TR75 (75kDa)[2]. Both receptors belong to TNF receptorsuperfamily because they share 28% homoIogy andcontain 4 conserved cysteine--rich subdomain in theirextracellular regions[3]. It is the uniqu…  相似文献   

12.
Current progress of China’s free ART program   总被引:5,自引:0,他引:5  
INTRODUCTION At the end of 2003, there were an estimated 840,000 people in China infected with HIV, among whom 80,000 were in need of antiretroviral therapy (ART) [1]. Since 1999, the annual rate of increase in reported HIV infec- tions has been around 30%, with growing numbers of females becoming infected [1]. The transmission of HIV/ AIDS in China has been through intravenous drug use (43. 2%) in the south, southwest, and western provinces; prior commercial blood and plasma selli…  相似文献   

13.
14.
COVID-19 (the COVID-19 is a type of disease and resulted from being infected by virus SARS-CoV-2) pandemic is threatening tens of millions of lives around the world [1]. To date, specific drugs or vaccines are still not available for fighting the SARS-CoV-2. Diagnosis and quarantine are still the effective strategies for preventing the virus from spreading. Up to now, various detection methods for SARS-CoV-2 have been developed [2], which play critical roles in controlling the pandemics. According to the targets to be detected, these methods can be divided into three classes: methods for the nucleic acid [3], antigens [4], and antibodies elicited by the virus in the host [5]. Among these methods, the ones for antigens and antibodies could produce results in 10–15 min [6], which are suitable for point-of-care diagnosis, especially the ones for antibodies [7]. Meanwhile, the asymptomatic cases [8] and the false-negative results of nucleic acid testing [9] make the detection methods based on antibodies the best alternatives. The proteins, used in methods for detection of antibodies elicited by SARS-CoV-2 in the host, are critical agents, which could affect the diagnosis results. Given the strong immunogenicity of the nucleocapsid (N protein), spike protein (S protein), and related domains [10] and the potential diagnosis values, we collected 9 S1 proteins, 3 N proteins, 5 S2-related proteins, and receptor-binding domains (RBDs) from ACROBiosystems (Beijing, China), ABclonal (Wuhan, China), Novoprotein (Shanghai, China), Sino Biological (Beijing, China), and KactusBiosystems (Shanghai, China) and fabricated a protein microarray (Fig. 1A) to assess their diagnosis performance. In addition, other proteins such as the angiotensin converting enzyme 2 (ACE2), envelop protein (E), 3C-like protease, and papain-like protease were also included (Fig. 1B).  相似文献   

15.
INTR0DUCTIONVascularsmoothmusclecellsp0ssessanumber0fNa transportsystems,namelyNa channels,Na -Ca' ,Na -H exchange,andNa -K -2Cl-c0-transp0rt[1].Hypothesizedr0lesf0rthesesystemsincluderegulati0n0fvasculart0ne,cellvolumeandcellproliferation.Inb0thexperimentalandhumanhypertensi0naberrationsinsm00thmusclecell,univalenti0ntransportsystemplayanimp0rtantroleinthepathogenesisandmaintenanceofhypertensi0n[2].Angiotensinc0nvertingenzyme(ACE)inhibitorsandCa2 antagonistsarewidelyusedforthetreatm…  相似文献   

16.
INTRODUCTIONApoptosis is a fundamental important biologicalprocess that is required to maintain the integrity andhomeostasis of multicenular organism[1]. It seemsthat apoptosis is a predominant type of active cendeath in the liver. Endogenous factors, such astransforming growth factor FI (TGF-gi), activin A,CD95 ligand, and tumor necrosis factor (TNF) maybe involved in induction of apoptosis in the liver[2].transforming growth factor P (TGF-P) is amember of a super-family of multifu…  相似文献   

17.
INTRODUCTIONOpioidreceptorsbelongtotheG-protein-coupledreceptorfamilythatischaracterizedbytheseventransmembranespanningdomainsinstructure.Threesubtypesoftheopioidreceptors(H,6,andK)havebeenclonedandcharacterizedthroughtheir1.CorrespondingauthorFunctionalexpressionofORLIandN/OFQduringmouseembryogenesisdistinctaffinitiesfordifferentopioidligands.TheseopioidreceptorsareallcoupledtotheinhibitoryGprotein(Gi)andnegativelyregulateadenylatecyclase[1].Opioidreceptor--likereceptor(ORLI),anew…  相似文献   

18.
Introduction HepatitisCvirus(HCV)isanRNAvirusthatcausesacuteor chronichepatitis,cirrhosis,andhepatocellularcarcinoma(HCC)[1,2].DespiterecentadvancesinthetherapyofHCV,eventhemostrecent combinationofpegylatedalpha-interferonandribavirinfailstoelimi nateinfectioninnearly50%ofthoseinfected[3,4].Nowadays,itis wellknownthatvaccineisstillthemostefficientwaystopreventvirus infection[5].Thestudyingofviralvaccinehasbeenhamperedbythe lackofanefficientcellculturesystem.Asaenvelopeglycoprotein,E2prot…  相似文献   

19.
Phenoloxidase (PO) plays an important role in the de-fense response to the foreign invaders, e.g. pathogens andparasites, in the formation of melanin as well as in cuticlesclerotization in insects [1]. PO is synthesized as azymogen, prophenoloxidase (PPO)…  相似文献   

20.
INTRODUCTIONEstrogen has been known to exert extensive effects via estrogen receptor (ER) on diverse physio-logical and develoPmental functions of the brain[1,2]. It has been observed that the distribution ofthe classical ER subtype-a (ERa) and the recentlycharacterized novel ER subtype--fi (ERg), and theirexpression patterns (ERcr/ERfi) vary greatly amongvarious brain regions[1, 3]. These evidences suggestthat each ER subtype may play a different role inestrogen's effects on the br…  相似文献   

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