introduction to medical...
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Introduction to Medical Microbiology
Di Qu (瞿涤)
MOH&MOE Key Lab of Medical Molecular VirologySchool of Basic Medical Sciences
Shanghai Medical College of Fudan University复旦大学上海医学院分子病毒学
教育部/卫生部重点实验室
Chapter 1, 3
• WHAT IS MICROBIOLOGY?
• WHAT IS MEDICAL MICROBIOLOGY?
• WHO STUDIES MEDICAL MICROBIOLOGY?
• WHY DO WE STUDY IT?
• WHERE DO WE STUDY IT?
• WHAT KNOWLEDGE WILL A STUDENT GAIN FROM
THIS COURSE?
• HOW DO WE STUDY IT?
Textbook: Jawetz et al. Medical Microbiology 26th ed.
How to use the textbook, it is not a easy book for beginner.Attending the lectures, and on time!Follow the lecture notes and keywords, read the textbook, and add more information to you notebook;Pay attention to the summary or objectives in the end of each chapter, and go through the review questionsIf there any questions, just ask;You may “catch” me in the lab after 4:00 pm at weekday or weekends morning (54237524) ; [email protected]: at the end of lecture ppt. or on elearningStudents: hand out on elearning in 2 weeks after lecture (deadline set on the elearning), email not acceptableTeacher: Feedback in 2 weeks (after the deadline for handing the homework) 3
Key WordsMedical microbiologyPROKARYOTES Eubacteria : Bacteria Mycoplasma,
Chlamydia, Spirochetes, Rickettsia, Actinomycetes
ARCHAEAEUKARYOTES: Fungi NOT CELL Virus Prion
Micro-organisms (or microbes for short) affect every aspect of life on Earthcan be friend or foe
– In all environments– Many beneficial aspects– Related to life processes
(food web, nutrient cycling…)– Only a minority are pathogenic， majority are
completely harmless– Most of our problems are caused by microbes
We couldn’t live without them, but they could live without us
http://pinterest.com/aswimm/microbiome/
We are not aloneThe Human Microbiome project: -DIVERSE
Healthy Soil Microbes, Healthy People
Microorganisms can be friend or foe
Microbes influence the evolution of hosts
Microbes interacting with hosts
http://pinterest.com/aswimm/microbiome/
Microbes and humans
Very few microbes are always pathogenic
Many microbes are potentially pathogenic
Most microbes are never pathogenic
Commensalism and symbiosis are presented as part of a continuum, distinguished by the identification of specific benefits derived by one or both members of a host-bacterial partnership.
共存 共生
Spectrum of virulence
Poliomyelitis in a child0.1-1% of infections are clinically apparent
Rubella50% of infections are clinically apparent
Rabies100% of infections are clinically apparent
The iceberg concept of infectious disease
Asymptomatic infection
Classicalclinical disease
Less severe disease
Medical microbiology Study of causative agents of human infectious diseases
and reactions to the infections.
Etiology, pathogenesis, laboratory diagnosis, specific
treatment and control of infection (immunization).
Biologic Relationships of Pathogenic Microorganisms
Figure 3-3 in Chapter 3, p.48
Based on rRNA data
Why no Virus in the “tree”?
PROKARYOTES
BACTERIA ARCHAEA
EUKARYOTES-Fungi -Plants-Animals
Eubacter-"True" bacteria -human pathogens-clinical or environmental-one kingdomArchaea -Environmental organisms
Chapter 3, p.43
真细菌 古细菌
VirusPrions
14
Kingdom PathogenicMicroorganisms
Type of Cells Knownspecies
Estimatedtotal species
Animal Helminths EukaryoticPlant None EukaryoticProtist Protozoa Eukaryotic
Fungi Eukaryotic 69,000 1,500,000Prokaryote Bacteria Prokaryotic 4760 40,000Not cell Viruses Noncellular 5,000 130,000
Viroids NoncellularPrions Noncellular
Biologic Relationships of Pathogenic Microorganisms
Characteristic Viruses Bacteria FungiCells No Yes YesSizediameter (mm)
0.02–0.2 1–5 3–10 (yeasts)
Nucleic acidChromosome
DNA or RNANo
DNA and RNAOne
DNA and RNAMore than one
Type of nucleus
None Prokaryotic, no nuclear membrane
Eukaryotic,withnuclear membrane
Ribosomes Absent 70S 80SMitochondria Absent Absent Present
Nature of outer surface
Protein capsid and lipoprotein envelope
Rigid wall containing peptidoglycan
Rigid wall containing chitin
Motility None Some NoneMethod of replication
Not binary fission Binary fission Budding or mitosis
Comparison of Medical Important Microbes
Medical Microbes are diverse-In genomes, in phenotypes, in metabolism…
Microbes cause disease in human:
Eukaryocytes : Fungi
Prokaryocytes: Bacteria
Major categories and Group of Bacteria:
common bacteria, Mycoplasma, Chlamydia, Spirochetes, Rickettsia, Actinomycetes
Viruses
Prions
Characteristic
Bacteria Spirochetes
Mycoplasma
Chlamydia
Rickettsia
Size(mm)
0.5~3.0 6~20 0.2~0.3 0.2~0.4 0.3~0.5
Cell wall yes yes No yes yesCell wall compositions
Cell wallwithpeptidoglycan
Outermembrane + cellwall
Sterol inthe cellmembrane
Similar to G -
bacteria
Share common antigen with B. proteus
Multiplication
Binaryfission
Binaryfission
Binaryfission
Intracellular,Binaryfission
Intracellular,Binaryfission
Filtration - - + + +
Major Categories of Bacteria
Viruses- no cellular structure, contain only either RNA or DNA as genome , rely on enzymes of hosts,
can only replicate in cells
MicroscopeElectron microscopeScan electron microscopeConfocal microscope
Taxonomic Ranks
Strain: one single isolate Type: sub-set of species Species: related strains Genus: related species Family: related genera
Formal Rank Example (E. coli)Kingdom ProkaryotaeDivision GracilicutesClass ScotobacteriaOrder EubacterialesFamily EnterobacteriaceaeGenus EscherichiaSpecies coliSubtype Escherichia coli O157: H7
Taxonomy Classification Identification Nomenclature
Capital lettersmall letter
BacillusB. anthracis
Clostridium tetaniC. Tetani
E. coli
20
Bacteria classification or identification
Growth
Morphology
Biochemical test
-Chemical Fingerprinting
Immunological test
-Serotyping
Genetic analysis
-Genotyping
- 16S ribosomal RNA
Virus classification different
Medical microbiology• Bacteriology – the science of bacteria, the causative
agents of a member of infectious diseases.• Virology – the science of viruses, non-cellular living
systems, capable of causing infectious diseases in man.• Mycology – the study of fungi pathogenic for man.• Anti-infection Immunology – the science which
concerned with mechanisms of body protection againstpathogenic microorganisms and foreign cells andsubstances.
Everyone has being infected experience
Microbes Infections in human
Clinical laboratoryPathologyImmunologyPharmcologyVaccinologyBiotechnologyResearchMicrobial Forensics…
Internal MedicineLemology（Infectious diseases）
PediatricsGynecologyObstetrics UrologySurgeryOtorhinolaryngologyGeneral medical practitioner…
* The first Nobel Prize in Physiology or Medicine.
Selected Novel Prizes in Physiology or Medicine1901* von Behring Diphtheria antitoxin1902 Ross Malaria transmission1905 Koch TB bacterium1908 Metchnikoff Phagocytes1945 Fleming, Chain, Florey Penicillin1952 Waksman Streptomycin1969 Delbrück, Hershey, Luria Viral replication1975 Baltimore, Dulbecco,
TeminTumor virus and RTase
1987 Tonegawa Antibody genetics1997 Prusiner Prions2005 Marshall, Warren Helicobacter and ulcers
2008 Barré-Sinoussi and Luc Montagnier
HIV
Hausen Papilloma and viruses
Where we study the Medical Microbiology Class room Medical Microbiogical Laboratory Clinics- self learning
http://www.udel.edu/mls/micro-lab.htm
Lectures, experiments, discussion and visiting hospital laboratory
Where the pathogenic microbes are from?
Reservoir: source of organisms– Humans– Animals (zoonoses)– Environment
Contact– direct– indirect
Droplet -aerosol Vehicle Vector
Emerging Infectious Disease
http://www.who.int/topics/emerging_diseases/en/
http://www.cdc.gov/
Nosocomial Infections
• Hospital-acquired• 5-15% of patients
acquire infection
PatientsTo patients
Doctors/Nurse/StaffsEquipment…
Global Handwashing Day2008-
•A lab coat or a large Lab shirt to cover yourself•NO eating… in the laboratory•Safety
Washing hands
The Keys to Learn Medical Microbiology
•Biological characteristics ( morphology, structure, metabolism, genetics, proteins)
•Related to pathogenesis
•Related to immune responses
•Useful for diagnosis
•Useful for prevention
•Useful for treatment
•(Useful for other purposes- Energy production, Oil clearance ,excellent model for study of life sciences)
Final grades determined according to the ratios in thefollowing：
Lecture exam-60% (midterm 20%, final 40%）;
Experiment exam-20%;
Attendance -10% (leave needed if you can not attend alecture)
Homework-10%（each lecture gives 2-3 questions, students choose some of those as homework, submit the homework to elearning before the deadline. Total 10 for the course)
http://www.mcgraw-hill.com.cn/digital/database.html-AccessMedicine: www.accessmedicine.com-Textbook
Download pictures, summary/objectivehttp://www.microbiologyonline.org.uk/home (SGM)
AccessMedicine: www.accessmedicine.com；AccessSurgery: www.accesssurgery.com 。读者在贵校的IP地址范围内，直接登录网址即可访问资源。其中，教师和学生互动的Custom Curriculum这个模块，因为是个性化的服务，所以需要授课老师或者学生先在网站上注册个人账号，随后才能使用。其中老师的个人账号可以设置教学课程，需要更严格一些的管理，所以在注册之后，请把账号相关信息发给我，我这边需要在后台激活一下，才可以使用。学生账号不能设置课程，也无需在后台激活。
• WHAT IS MICROBIOLOGY?
• WHAT IS MEDICAL MICROBIOLOGY?
• WHO STUDIES MEDICAL MICROBIOLOGY?
• WHY DO WE STUDY IT?
• WHERE DO WE STUDY IT?
• WHAT KNOWLEDGE WILL A STUDENT GAIN FROM
THIS COURSE?
• HOW DO WE STUDY IT?
Textbook: Jawetz et al. Medical Microbiology 26th ed.
