医学微生物学2.doc

二, 教学目的及要求：医学微生物学是生命科学中的重要学科，是研究病原微生物的形态、结构、生命活动规律以及与机体相互关系的一门重要的基础医学二级学科。为医学生学习临床的感染性疾病、传染病、超敏反应性疾病和肿瘤发生等奠定重要的理论基础。要求学生熟悉微生物学基本理论知识，掌握病原微生物的致病机制及其诊断、预防的主要措施。三, 教学内容：医学微生物学是研究病原微生物的形态、结构、生命活动规律以及与机体相互关系的一门重要的基础医学学科，将为临床各科的感染性疾病、传染病、超敏反应性疾病和肿瘤发生等的学习奠定重要的理论基础。同时,还开设了医学微生物学实验课,培养学生的动手能力和分析问题的能力. 本课程主要讲述微生物的基本概念、各类微生物的生物学特性、感染及抗感染免疫的机理、感染性疾病的诊断、预防和治疗原则。针对五年制医学类本科生，着重介绍与人类疾病相关的各种病原微生物（以常见的病原性细菌和病毒为主）的形态结构、培养特性、生化反应、抗原构造、分类、抵抗力等各种生物学特性，致病机理及所致疾病，病原体的分离培养方法及鉴定原则，相关疾病的预防及治疗原则。通过学习，使同学牢固树立“有菌观念”并掌握无菌操作的原则，学会保护自己，也为将来专业课的学习奠定良好的基础。同时，针对七年制学生的特点，不仅讲述上述知识，而且结合目前临床感染的现状，向同学介绍新现和再现的病原微生物、有关细菌的耐药、微生态平衡与失调、医院内感染及肿瘤相关病毒的知识，以适应七年制教学的要求，拓展学生的视野，提高学生的科学研究能力，培养更高层次的学生。大纲中的英文黑体字内容 ,要求掌握 ; 其他内容要求熟悉 . 第 1 页共 20 页Medical Microbiology Outline for 7 and 8 Years Students, as well as Basic Medicine Students Introduction （1 h）一. Definition, Classification and Characteristics of Microorganisms. (一) Concept: A kind of microorganism which is small bodies, simple structure, not visible by the naked eyes, visible usually only with light microscope or electromicroscope. (二) Classification: 1. Non-cellular type: Virus; 2. Prokaryotic group; 3. Eukaryotic group (三) Characteristics. 二. Relation between Microbes and Human. Be more beneficial than harmful to Human. 三. Developmental history of microbiology (一) Experiential period of microbiology (二) Experimental period of microbiology 1. Morphological period 2. Physiological period: Louis Pasteur; Robert Koch; Iwanovsky (三) Modern Microbiological period. Chap.1 Bacterial Biological Properties (1.5 h) 一. Bacterial Size and Morphology (一) unites of measurement: m (micron or micrometer); nm; (二) Basic morphology: Coccus; Bacillus; Spirillar bacterium; (Vibrio; Spirillum;) (三) Arrangement of bacteria 二. Basic structure of bacteria (一) Cell Wall 第 2 页共 20 页 1. Function 2. Composition. Main component: Peptidoglycan (i.e. mucopeptide) (1)Backbone: ;（2）Side chain;. （3）(Gly)5 peptide cross-bridge : (4) Cell Wall Comparison between Gram+ and Gram-bacteria. (5) L Type bacteria (二) Cell membrane ; Cytoplasma; Nucleus; Mesosome, Chondroid 三. Special structures of bacteria. 1. Capsule 2. Flagellum 3. Pilus or Fimbriae 4. Spore 四. Examination and Staining: Simple staining:; Complex staining: Procedure of Grams Stain; Practical Significance of Grams stain: Bacterial Physiology (2.5 h) 一. Chemical Composition and Physical Characteristics of Bacteria. (Self-learning) 二. Growth and Mutiplication of bacteria (一) Nutritional types of bacteria (二) Basic requirment of bacterial mutiplication 1. Nutriention: water; carbon source; nitrogen source; inorganic salt; growth factors (Enzymes, Amino acid) 2. Optimal pH: 7.8-7.6, 8.5-9 for vibro; 3. Proper Temperature: 4. Definite gaseous: O2, CO2, N2 Anaerobic principles of anaerobes (1) Do not possess cytochrome oxidase nor cytochrome. (2) Do not possess hydrogen peroxidase, catalase and superoxide dismutase (SOD). 三. Methods and speed of bacteria growth. 第 3 页共 20 页 Manner: Simple binary fission Speed: one generation/15-20; one generation/20h. (T.b.) Typical growth curve of bacteria. 1. Lag phase: a period of adaptation; 2. Logarithmic phase: rapid growth 3. Stational phase; 4. Decline phase 四. Cultivation of bacteria (一) Classification of media (二) The phenomenon of bacterial growth (三) Significances of Products of medical importance: 1. Pyrogen : 2. Exotoxins :3. Endotoxins: 4. Antibiotics: 5. Bacteriocin: 6. Vitamin: Chap 2. Bacterial genetics and variation (3 h) 一. Bacterial variation: 1. Morphological and structure change ; 2. Lose of virulence; 3. Antibiotics-resistant variation.; 4. Colonial variation. 二. Genetic basis of bacteria (一) Plasmid: F factor ; R factor; Col factor. (二) Bacteriophage 1. Properties of phage: 2. Relation between host cell and phage: 2.1 Virulent phage; 2.2 Temperate phage (Lysogenic phage) 2.3 Lysogenic state: Prophage; 2.4 Nature of the lysogenic bacteium. 3. Application of phage (三) transposable element (jumping genes) 三. Mechanism of Bacterial Variation. (一) Mutation. (self-learning) 第 4 页共 20 页 (二）Gene transfer and recombination. 1. Transformation: The Naked DNA derive from one cell is taken up by another recipient and DNA recombination can take place. 2. Transduction Gene transfer mediated by a bacteriophage. i.e. the DNA of one bacterial cell is introduced into another recipient by bacteriophage infection. (1) Generalized transduction any of donor genetic information transfer to the chromosome of recipient (2) Restricted transduction Bacteriophage can only transfer certain genes from the donor to recipient cells. 3. Lysogenic Conversion: Some bacteria are infected by a temperate phage and their DNA recombinated together and expressed. 4. Conjugation : Many bacteria can transfer genetic information (chromosome, plasmid) through contact of the two cells by way of sex pili四Practical Significance of Bacterial Variation Diagnosis: nontypical strain; Prevention: vaccine; Clinical treatment. Genetic engineering; Gene thrapy. Chap. 3 Bacterial Drug-Resistance (3 h) 1Introduction Antibiotic resistanc in human and animal; mutiple antibiotic resistance, mar 2. Main mechanisms of antibiotic resistance formation 2.1 Genetic Mechanisms Plasmid Mediated Drug-Resistance Drug-resistance could be transmitted by conjugation. transformation and transduction. Transposon : IS ; Tn ; Mu。 2.2 Biochemical mechanism Target site modification: PBPs ; DNA gyrase; gyrA, gyrB gene mutation. 第 5 页共 20 页 modified enzyme: lactamase extended spectrum lactamase aminoglycoside-modifiled enzymes active efflux pump Change of permeability of bacterial cell wall : porin, OmpF ; OmpC。 Biofilm 3. Common drug-resistant bacteria in hospital infection 4. Prevention and treatment principles Minimal inhibitory concentration , MIC; Minimal bactericidal concentration , MBC Chap.4 Bacterial infection and pathogenesis (3 h) Normal flora and opportunitists 一. Bacterial infection (一) infectious sources. 1. Exogenous infection: patients; carrier; animal. 2. Endogenous infection (二) infectious types 1. Inapparent infection (subclinical infection) 2. Apparent infection: Toxemia; Septicemia; Bacteremia; Pyemia; Endotoxemia.二. Bacterial Pathogenecity Virulence: Invasiveness or Toxigenicity Number of bacterial entry: Portal entry. Bacterial virulence factors LD50 (Lethal Dose 50) the number of microbes that must be administered to kill 50% of the animals. 1. Bacterial related structures: pili, LTA,. capsule,. microcapsule 第 6 页共 20 页 2. Invasive enzyme Hyaluronidase, Coagulase: 3. Bacterial toxin.: Exotoxin ; Endotoxin ; Differentiation of exotoxin and endotoxin 三. Pathogenicity of virulent factors: Superantigen; Pathogenicity island Chap.5 General properties of viruses (3 h) 一Size and shape: 二Structure and composition: Necleocapsid =Nucleic acid +capsid Virion = Nucleocapsid (Naked virus) = Nucleocapsid + Envelope (envelope virus) 三Multiplication: Replication; Replicative cycle 1. Adsorption and penetration; 2. Uncoating:; 3. Biosynthesis: SSRNA+ , SSRNA-, Retrovirus,. mRNA transcription; Early protein translation; Nucleic acid replication; (Progency) mRNA transcription; Late protein translation. 4. Assembly, maturation and release.; release by lysis or budding (二) Growth Curve of virus: Eclipse phase; Logarithmic phase; cell death phase. (三) Interference 四 . Genetics and Variation (一) Viral variation types (二) viral molecular genetics. (三) practice significance of viral variation. 第 7 页共 20 页 1. Research in viral pathogenesis; 2. In diagnosis; 3. In treatment ; 4. In prevention; 5. In genetic engineering.五. Reaction to physical and chemical agents (一) Physical factors: 1. Temperature: Resistant to cold be stored -70; Susceptible to heat 2. pH (二) Chemical factors 六. Classification of viruses 1. Usually according to transmission routes; 2. Subvirus: satellites virus (virusoid 拟病毒); viroid类病毒; prion朊粒. Chap.6 Viral Infection and Pathogenesis (3 h) 一. Infection 1. Transmission and Entrance (1) Horizontal transmission (between individuals): (2) Vertical transmission (mother to baby) 2. Spreading within the host 二. Viral infectious forms: (一) Inapparent viral infection (subclinical infection) (二) Apparent infection (Dominant infection) 三. Viral Pathogenesis: (一) Effect on host cell 1. Cytocidal effect; 2. Steady state infection. Cell membrane effect; 第 8 页共 20 页 3. Cell apoptosis; 4. Integration; 5. Cell transformation; 6. Inclusion body formation (Negribody). (二) Effect on host 1. Direct damage. Polio.v motor neuron 2. Immunopathology Inflammation (Type II、III、IV hypersensitivity) 3. Direct effect on immune system Chap.7 Fungi (2 h) 一. Characteristics: Eucaryotic, including Unicellularyeasts.yeast-like organism, cryptococcus neoformans Multicellularmolds: hyphae spores Sabourauds medium二. Classification and disease 1. Dermatophytes, causing superficial mycoses (skin, hair, nail). 2. Causing opportunistic mycoses (1) Candida albicans: (2) Cryptococcus neoformans 3. Causing allergy; 4. Causing Mycocoxicosis; 5. Causing Cancer-related disease.三. Detection: 1. direct observed by microscope: hair; 2. Culture: 3. Animal inoculation: cryptococcus neoformans. Chap.8 Chlamydia (3 h) C. trachomatis. 1. both DNA+RNA. Binary fission. 2. intracellular multiplication. 第 9 页共 20 页 Elementaly bodyhas infectivity. Initial bodyNo infectious. Mycoplasma 1. procaryotic. smallest (0.20.3um) free-living microorganisms, no cell wall, highly pleomorphic, can pass through filtres that retain most bacteria. 2. Colonies minute (0.2mm), show a “fried-egg appearance” 3. Exist in mouth, respiratory and genito-urinary tracts, common contaminants of tissue-culture. 4. lmportant species: M. pneumoniae -primary atypical pneumonia; M. hominis ; genito-urinary infections.; Ureaplasma urealyticum Spirochete 一. Characteristics: 1. Procaryotic, slender, flexible, helical, actively motile organisms. 2. Not easily to stain, always use: dark-field microscopy for living specimens silver-impregnation for fixed specimens negative stain 二. Classification: three genera of pathogenic spirochetes: 1. Leptospira; 2. Treponema:;3. Borrelia. Rickettsia 1. Procaryotic 2. Obligate intracellular parasites. 3. Most of them infect both human & animals, transmitted by arthropod vectors. 4. Important species: 5. Share common antigens with certain strains of proteus (OX19, OX2, OXk). Weil-Felix test is a famous test to help diagnosis 第 10 页共 20 页 Actinomyces procaryotic. Taxonomic position between Fungi and bacteria. Important speciesA. Israelii “sulfur granules”in pus or tissue are diagnostic Chap. 9 Anti-infection Immunity (3 h) (Human Immunity against Bacterial and Viral Infection) 一. Nonspecific immunity 二. Specific immunity 1. Humoral immunity ;Cellular immunity; 2. Immunity to extracellular bacterium; 3. Immunity to intracellular bacterium; 4. Immunity to exotoxin. 三. Antiviral immunity 1. Non-Specific Immunity (Innate resistance):; 2. Specific Immunity; 3. Synergism of immune factors; 4. Duration of acquired immunity. Chap.10 Microbiological Diagnosis Prevention &Treatment of Bacterial and Viral Infection (3 h)一. Procedure of detection for pathogenic bacteria 1. Sample collection and treatment ; To Smear and Stain; 2. Isolation and Culture; 3. Biological tests; 4. Serological tests. (Identification); 5. Animal tests; 6. Drugsensitive test; 7. Phage typing ; 8. Molecular technology: fingerprinting ,DNA hybridization; PCR 9. Serological diagnosis : For detection of Antibodies.二. Microbiologic diagnosis for virus 1. Sample collection and treatment Rapid diagnosis (Direct identification of virus, viral nucleic acid or viral Ag); 第 11 页共 20 页 Virus particles EM or IEM; Inclusion body microscopy; Immuno-Label techniques; Other Immunoassay: RIA, ELISA, IF; Nucleic acid hybridization technique; Isolation and identification of viruses. 2. Culture method selection and cultivation Animal inoculation ; Egg-embryo inoculation ; Tissue culture (cell culture): Primary cell ; Cell line ; Blind subculture Recognition of virus growing in cell culture: CPE Identification: Serological identification; Nucleic acid identification 3: Serologic diagnosis (detect unknown Ab) methods: 4. Quantification of virus Electron microscopy either alive or inactivated virus Hemagglutination Plaque assay (LD50 , 50% Lethal) )50% effect dose (ID50, TCID50alive virus 三. Prevention (control) and treatment Enhance the immunity (resistance) of human body Pyogenic Coccus（3 h）一Common features and classification .二Comparison between staphylococcus and streptococcus . (一) Biological Characterisation : Morphology and staining ;.Culture;. Ag structure : (二) Pathogenic substances and diseases caused . (三) Microbiological diagnosis . 1 . Stained smear . 2 . Isolation and culture . 、 strain (四) Priniciple of prevention and treatment . 第 12 页共 20 页 Personal hygiene; Carriers; Hospital cross infection; Patients. 三. Pneumococcus (streptococcus pneumoniae) Pathogenisis is relate to capsule Pneumococcal pneumonia 四. Meningococcus Pathogenisis is related to endotoxin and capsule Meningitis 五. Gonococcus: Pathogenisis Enteric bacilli（3 h） Common properties of Enteric bacilli .一Escherichia Coli (E . Coli) (一) Basic properties : (二)Pathogenisis : Apportunitistic bacilli . Pathogenic E . Coli . 一） Pathogenic factors . 1 . Colonization factor (adhesin) 2 . Enterotoxin (Exotoxin) Heat Labile erterotoxin(LT) : ATP CAMP Heat stable enterotoxin(ST) : GTP CGMP 二） diseases . 1 . infection in outside of intestinal tract . Pyogenic diseases : peritonitis , cholecystitis , pyelitis . 2 . diarrhea (三). Diagnostic tests: for pathogen: 1. Specimen: urine, stool , blood. pus. 第 13 页共 20 页 2. isolation and identification: Hygienic tests. 二. Shigella and Salmonella (一) Comparison in biological properties. (二) Pathogenisis. 1. Pathogenic factors. 2. Infection. (三)diagnostic laboratory test Specimens; Procedures: (四) Prevention and Control food. feces. fly. fingers. Vibrio Cholerae（1 h） (Classical biotype and E1 Tor biotype) 一. Basic Properties. 二. Pathogenisis. V. Cholerae hibitate only adherence to the intestinal epithelial cellular surface. not enter into cells and blood. Cholerae enterotoxin: basic structure and pathogenic mechanism. 三. Diagnostic laboratory test. rapid diagnosis; Culture. 四. Prevention Anaerobic bacteria（2 h） (Clostridium) Cl.Tetani ; Cl.Perfringens ; Cl.Botulinum 一Common characteristics Morphology and stain: G+ Bacilli; posses spore. 第 14 页共 20 页 Culture；Resistant；Exotoxin；二. Pathogenicity. *(一) Pathogenic factors: Cl. Tetani Cl. Perfringens Cl.Botulinum Tetanospasmin. Tetanolysin; Exotoxin (12) invasive enzyme; Exotoxin (8) (二) Diseases: 三. Prevention and treatment. 四. Diagnostic laboratory tests. Corynebacterium（1 h） (diphtheria bacilli)一. Basic Properties. *1. Morphology and stain: G+、Club-shaped、 Metachromatic granules. 2. Culture:* Loeffler serum medium. 二. Pathogenisis *1. Pathogenic factors: Exotoxin produced by Lysogenic Corynebacterium. *2. Pathogenic mechanism. diphtheria toxin 3. Diseases. Endocarditis ; Pseudomembrane ; paralysis of the soft palate. 三. Diagnostic laboratory tests: Swab from nose, throat.: Abert stain.; Loeffler serum medium. ; Elek plate test. In vitro 四. Prevention and treatment. Mycobacterium（2 h）一. General characteristics Morphology; Culture.; Resistance 二. Pathogenicity: without exotoxin 、endotoxin and invasive enzymes; 第 15 页共 20 页 三 . Immunity-infecious immunity; old tuberculin (OT),purified protein derivative (PPD); tuberculin test (principle, procedure, results and explanation). 四, Baterial diagnosis Specimens-sputum, pus, CSF, stool, urine, etc. Microscopic examination- Acid fast stain. Culture-solid culture media method; slide culture media method. Animal inoculation-guinea pig. 五, Prevention : BCG vaccination. Influenza virus（2 h）一. Biological properties Morphology and structure Surface antigens: HA, NA Relationship between the antigenic variation and epidemiology Antigenic drift: median or small epidemic Antigenic shift: large scale epidemic Variation of HA and NA of influenza virus二. Pathogenicity and immunity 1Source of infection: patients and carriers. 2. Pathogenesis 3. Laboratory diagnosis Isolation and identification of viruses. Serological diagnosis: HI. NT. 4. Prophylaxis and treatment: personal hygiene; vaccines. Retrovirus （2 h）一. Basic Properties:二. Classification: (3 Subfamilies) 第 16 页共 20 页HIV 一. Introduction: 二. Epidemiology: 三. Pathogenic mechanism and clinical symptoms: CD4 recepter;CCR5;CXCR4 ; T4/T8 1; Cellular Immunity ARC: feve