1、1. Pass內(nèi)毒素外毒素的主要區(qū)別？ExotoxinEndotoxinExcreted by living cells, mainly by G+ bacteriaIntegral part of G- bacteria cell wall, liberated upon bacteria disintegrationpolypeptideLPS, main toxic part- lipid AHeat-unstableHeat-stable, 160, 24hr destroyStrong antigenicity, induce body to produce antitoxin, e

2、xotoxintoxoidWeak antigenicity, cant convert into toxiodHighly toxicWeakly toxicHigh selection for tissues: neurotoxin, cytotoxin, enterotoxinNon-specific, all endotoxins produce the same symptomsfever; WBC reaction; endotoxemia and shock; DIC.Structure: A subunit-B subunit. A subunit: toxic part; B

3、 subunit: non-toxic, bind receptor of sensitive cellLPS: lipid A, core polysaccharide, specific polysaccharide(O antigen)2.Pass mechanism of cholera pathogenic:霍亂1)pathogenic factor: invasiveness: flagellum, pili; cholera enterotoxin: contain A and B subunits. A subunit-Ag weak, active unit, enters

4、the cell, stimulates adenylate cyclase-cAMP-secreting effect-severe diarrhea; B subunit-Ag high, bound unit, attaches to receptor on epithelial cells of small intestine.2)mechanism: Organisms-oral route(contaminated water, food)-stomach-attach to the small intestine epithelialcells(non-penetration)-

5、multiplication-cholera enterotoxin-adenylate cyclase-cAMP concentration-secreting effect-severe diarrhea(rice-water stools)-rapid dehydration and hypovolaemic shock低血容量休克-die in 1224 hours.Ps. Transmission: polluted water and food, by mouth3.Pass Clostridium tetani- pathogenesis破傷風(fēng)1)condition:Wound+

6、sporeDeep, narrow and contaminated by soil;Necrotic壞死的 tissue;Companied with aerobe or facultative anaerobe infection.2)pathogenic substance:Tetanospasmin破傷風(fēng)痙攣毒素- neurotoxin: proteinTetanolysin破傷風(fēng)溶血毒素3)mechanism:根據(jù)課件整理一下Spores-vegetative bacteria細菌繁殖體-grow locally-tetanospasmin-( along nerve fiber/

7、blood)-anterior horn cells of spinal cord, binds to ganglioside receptor神經(jīng)節(jié)苷酯受體 and blocks release of inhibitory mediators-cause convulsive痙攣的 contraction of voluntary muscle.4.Pass dsDNA病毒的復(fù)制周期答：復(fù)制周期依次包括：吸附。穿入。脫殼。生物合成。組裝、成熟和釋放。Replication cycle: adsorption-penetration-uncoating-biomolecular synthes

8、is-assembly-maturation-release5.Pass HIV致病機制：Pathogenesis: Gp120 of HIV select CD4 molecule of T4 cells;Viruses multiply in T4 cells;Cell-mediated immunodeficiency;Opportunistic infections and tumor occurs;DeathHIV損傷CD4 T細胞的機制：導(dǎo)致CD4 T細胞融合，最終導(dǎo)致細胞的溶解； CTL對CD4 T細胞的直接殺傷作用，抗體介導(dǎo)的ADCC作用，NK細胞的殺傷作用；誘導(dǎo)CD4 T細胞

9、細胞凋亡；HIV復(fù)制產(chǎn)生大量未整合的病毒DNA，抑制細胞正常的生物合成；HIV可作為超抗原激活大量CD4 T細胞。6，gp41與細胞膜上MHC二類分子有同源性homology，誘導(dǎo)產(chǎn)生具有交叉反應(yīng)的自身抗體，致使T細胞損傷。 Destruction of T4 cells is achieved by: Viral replicationSyncytium合胞體 formation via membrane gp120 binding to cell CD4 antigenCytotoxic T cell lysis of infected cellsCytotoxic T cell

10、 lysis of T4 cells carrying gp120 released from infected cells  Antibody-dependent cell cytotoxicity. Induce appoptosis.8.Pass functions of special cell structure of bacteria:1) capsule: slime layer outside the cell wall, composed of polysaccharide or polypeptide.Functions: anti-phagocytos

11、is; adherence; protect from lesions by harmful substances; anti-dry; antigenicity2) flagellum: originate from cell membraneFunctions: motility; antigenicity(H antigen); pathogenicity: some bacteria3) pilus: Common pilus: adhere to surface of cell, associated with pathogenicitySex pilus: transfer gen

12、etic material (DNA) during bacteria conjugation4) spore: resting form, forming: inadequate nutritionFunction: highly resistant to heat, chemicals, dry9. Pass streptococcus 致病物質(zhì)及主要疾病： 1) invasivenessAdhesion: LTA(脂磷壁酸)、M protein-adhere to sensitive cell2) enzyme:Hyaluronidase: split hyaluronic acidba

13、cteria spreadStreptokinase: lyse fibrin, prevent plasma clottingbacteria spreadStreptodornase(鏈道酶): resolve DNAbacteria spread3)toxin-exotoxinStreptolysin(hemolysin)鏈球菌溶血素: destroy blood cellsPyrogenic exotoxin致熱外毒素：superantigen, cause scarlet fever猩紅熱Disease:Pyogenic infection(化膿性感染)Toxin disease:

14、scarlet feverNon-pyogenic infection(1) rheumatic fever(2) acute glomerulonephritis10.Pass what is plasmid? Its features.plasmid is the extrachromosomal genetic elements which is small circular double-stranded DNA molecules. They are capable of self-replication and contain genes that determine many p

15、roperties. Features:1) extra-chromosomal genetic material circle2) ds DNA3) dispensible(非必需的)4) replicated independently5) carry genetic information6) control a wide range of function to bacteriafactor Fcontrol sex pilifactor Rcontrol drug resistance7) transferred between bacteria11.Pass what is lat

16、ent infection. Take HSV as example.Latent infection: virus is usually not detectable but patient may have periodic out-breaks of disease. In this infection, the acute disease is followed by an asymptomatic period during which the virus remains in a latent state.12.Pass distributions and functions of

17、 normal flora1)distributions: skin, oral cavity, intestinal tract, vagina2)functions:antagonism: biological barriernutrient synthesize: VB, VKimmune: enhance and develop the maturation of immune systemanti-caducity(抗衰老)anti-tumor13.Pass 結(jié)核分枝桿菌的傳播途徑和致病因子：1)route: by respiratory tract, digestive tract

18、 or damaged skin.2)pathogenic substances:lipid：A.cord factor: associated with virulence; inhibit migration of leukocyte to form chronic granuloma; bind to mitochondrial membranes, influence the cell respiration B. Phosphatide磷脂: stimulate monocytes proliferation-form tubercleC. Wax D: act as an adju

19、vant, cause DTHD. Sulfatides硫酸腦苷脂: inhibit the fusion of phagosome and lysosomeprotein tuberculin結(jié)核菌素 Tuberculin+waxD-DTH Ag-Ab(no protection)polysaccharide :combine with waxD- cell filtrationmycobactin(分枝菌生長素)致病機制加上這句話：No endotoxin, exotoxin, no capsule, and no invasiveness enzyme致病機制：No endotoxin,

20、 exotoxin, no capsule, and no invasiveness enzyme.加上上面的致病物質(zhì)Primary tuberculosis: organism-respiratory tract-pulmonary alveoli-lesion-lymph nodes-swelling-fibrosis-natural curePost primary tuberculosis: organism-infection again-inflammation-necrosis壞死-tubercle結(jié)節(jié)-fibrosis纖維化14.Pass HBV基因組及其編碼的蛋白。傳染源，傳

21、播途徑長鏈為負鏈，固定長度；短鏈為正鏈，長度可變負鏈negative strand DNA有四個區(qū)：S、C、P、XS：HBsAg, PreS1Ag, PreS2AgC: HBeAg, HBcAgP: DNA polymerase, reverse transcriptase, RNaseHX: HBx(x protein)-associated with tumorSource of infection: patients, HBsAg carrierTransmission way : blood or blood products; sexual contact; vertical tra

22、nsmission(birth, breast-feeding)防治原則：prevention: vaccine: recombinant HBsAg vaccines;serum derived vaccine Treatment: interferon; lamividine etcPass乙肝五項，微生物檢測的成分及意義HBsAg, anti-HBsAg, anti-HBcAg, HBeAg, anti-HBeAgHBsAg: a patient infected with HBV; acute infection recently; a carrierAnti-HBsAg: prote

23、ctive or recoveryAnti-HBcAg: viral multiplication; active infection;infectiousHBeAg:viral multiplication; active infection; infectiousAnti-HBeAg:multiplication and active infection are reduced; has less infectious附：HBc一般不易游離于血循環(huán)中，故不易從患者血清中查出。但HBcAg可在肝細胞膜表面表達，抗原很強，可誘導(dǎo)宿主CTL細胞反應(yīng)，并能刺激機體產(chǎn)生非保護性抗體HBc抗體。HBc

24、AgZ存在于HBV核衣殼表面，或位于感染的肝細胞中，血中不易檢測到，故不用于HBV標(biāo)志物的常規(guī)檢查。15.Pass tuberculin test: using OT or PPD to detect whether it can cause DTH of skin, in order to judge if body has the immunity to tubercle bacillus. Principle: DTH Method: PPD-injection-4872h later-induration硬結(jié), inflamed紅腫 Results: <5mm, no TB in

25、fection; Early stage of primary infection; Severe patient of TB Cell immune function decrease(virus infection, use of immunosuppressive drug)5mm<<15mm, hypersensitivie to TB; immunity>15m, active infection perhapsApplication: basis of BCG inoculation, detect immunity effect Diagnosis of you

26、ng children tuberculosis Epidemiological investigation Cellular immunity test of patients with tumor16.Pass 支原體與細菌L型的比較：MycoplasmaL-bacteriacolonyFried-egg(bigger)Fried-eggMorphologyMany(bigger)manyCell wallnoNo or deletionReason for no cell wallgeneticPhenotype variation, can recoverCell membrane1/

27、3 is cholesterolNo cholesterolLiquid cultureLow milkymilky17.Pass衣原體chlamydia的共同特征：圓形或橢圓形，革蘭陰性同時含有DNA和RNA嚴格真核細胞內(nèi)寄生具有類似格蘭陰性菌的細胞壁必須由宿主細胞提供所有代謝活動的能量來源獨特的life cycle: elementary body, initial body18.Pass 比較原體和始體：Elementary body: infection form, has cell wall, extracellular parasiteInitial body: replicati

28、on form, has no cell wall, intracellular parasite19. Characteristics of IFNs 1. anti-viral functions: 1) act indirectly on virus 2) broad-spectrum antiviral activity 3) host species specific and cellular selective: inhibit viral replication only in the species in which it was produced 4) act in the

29、early stage of viral infection2. anti-tumor 3. immune regulationAntiviral mechanisms:IFN-combine with IFN receptor on cell surface-AVP gene activated-AVP mRNA transcribed-AVP synthesis2,5-A synthetase: degrade mRNA of virusProtein kinase: inhibit protein synthesis of virus21. HA功能hemagglutinin（血凝素）：

30、流感病毒2units: HA1and HA2 * agglutinate human and some animal RBC * be related to the adsorption of viruses (receptor : neuraminic acid神經(jīng)氨酸，即唾液酸受體 ) * antigenicity: show great variability Abs to the HA are protective, neutralize viral infectivity. 22.Pass Effects of viral infection on cells 1）. cytocid

31、al infection (naked viruses) virus which infect and replicate within cells causing the cells to lyse when the progeny virions are releaed. mainly found in naked viruses. CPE (cytopathic effect )細胞病變效應(yīng)2）. steady state infection (enveloped viruses) viruses are produced from the infected cells but the

32、cells are not killed by the process. Lead to: integration of viral Ag in host cell membrane, so the immune system may recognize it as foreign; cell fusion.3）. cell apoptosis virus or viral protein induce the process.4）. viral genome integration integration: integration of the viral genome into cellu

33、lar DNA5）. cell hyperplasia增生 and transformation morphous change loss of contact inhibition immortalization 不朽永生 new antigen6）. inclusion bodyround, oval or irregular-shaped bodies occurring in the cytoplasm or nucleus of virus-infected cells, can be seen under the microscope.23.Pass the mechanism o

34、f bacterial variation.Variation examples:Shape and structure variation;Colony variation:Virulence variation;Resistance variation.(1)Mutation: a stable heritable change of bacterial gene; spontaneous or induced1)point mutation: base replacements;base deletion lost;base insertion 2)multiple mutation:

35、rearrangement(2)genetic transfer:Genetic substance of bacteria is transfered to another bacteria.1)transformation: recipient bacteria directly takes up exogenous DNA of donor bacteria. Competence: bacterial state- at which bacteria can take up DNA from environment in log phase.2)transduction: Gene t

36、ransfer from a donor to a recipient by way of a bacteriophage generalized transduction: any fragment of donor bacteria is transferredspecialized transduction: the fragment near attachment is transferred 3)Conjugation: bacterial DNA is transferred from donor bacteria to recipient bacteria by sex pilu

37、s4)Lysogenic conversion:The presence of prophage DNA constitutes a genetic alteration to the host cell 5)Protoplast fusion24.Pass The Function of Cell Wall 1) protection 2) keep the constant shape 3) antigenicity 4) exchange material25.細菌的致病機制：(1)virulence1) invasiveness:Surface structure:Adhesin: p

38、ili adhesin; no-pili adhesin;Capsule and microcapsule;Flagella;Bacterial biofilm.invasive substance:Invasin;Invasive enzymeimmune escape:Anti-phagocytosis;Produce IgA proteinase;Antigenic shift;Interfere complement activity.2) toxin:exotoxin; endotoxin.(2)infective sites, portal or route(3)infective

39、 numbers(4)the immunity of host26. the mechanism of Drug Resistance.細菌抗藥機制(1) genetic mechanism:1) intrinsic resistance: bacteria absence of the target for the action of the drug.2) acquired resistance: a result of genetic change and subsequent selection by antimicrobial drugs.chromosomal mutationac

40、quisition of plasmid carrying a resistance geneacquisition of transposable element carrying a resistance gene.(2) biochemical mechanism:modified enzymes鈍化酶. Bacteria produce, inactivate the drugs.bacteria develop an altered structural target for the antibacterial drug.bacteria decrease their permeab

41、ility, efflux pump system主動外排.27.Pass 幾種病毒疫苗：Measles-mumps-rubella vaccine, MMRPoliovirusoralRabies virusAll live attenuated vaccine.28.Pass virulence factors of G+ bacteria:(1) structural substance of bacterial: adhesion: LTA脂磷壁酸, ect.(2) capsule and invasive enzyme(3) exotoxin29.Pass pathogenicity

42、 of S. aureus金葡菌的致病1. Pathogenic Factors1). Invasiveness (1) Surface structures SPA capsule Adherence & anti-phagocytosis peptidoglycan teichoic acid (2) Invasive Enzyme Coagulase a) to inhibit the phagocytosis of phagocytes and damage of bactericide substances in serum by coating the organisms

43、with fibrin; b) to prevent bacteria spreadingincluding: free coagulase; bound coagulase.2). Toxin - exotoxin(1) . Staphylolysin: a、b、g、dcytotoxic effects on phagocytic and tissue cells (2).Leukocidin: cytotoxic effects on Killing PMN & MF(3).Enterotoxin:Cause a food poisoning characterized by se

44、vere vomiting and diarrhea;(4). Exfoliatin剝脫素: Cause blistering of skin (5). Toxic shock syndrome toxin-1 (TSST-1): induce TSS2. diseases1) Invasive diseases - pyogenic infection  (1) local infection: skin infection: folliculitis; boil; carbuncle; impetigo (thick pus; limited local area) (2) organ infection: pneumonia; meningitis; endocarditis (3) Systemic infection: septicemia; pyemia2) toxin diseases - exotoxin (1) Food poisoning (enterotoxin)  (2) SSSS (staphylococcal scalded skin syndrome)  (3) TSS (Toxic shock syndrome) 30.Pass pathogenicity of Streptococcus