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Final Exam
everything
260
Microbiology
Undergraduate 3
08/30/2011

Additional Microbiology Flashcards

 


 

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Term
Important features of the domain Archaea
Definition
-does not include pathogens
-can survive in many different environments (halophiles=130-150F water, methanogens=animal colons)
-lack peptidoglycan
Term
What is endospore formation?
Definition
-survival mechanism
-makes the bacteria extremely resistant to outside forces
-this is not a reproductive mechanism
Term
Antisepsis (Antiseptic)
Definition
Chemicals applied to the body surfaces to destroy or inhibit vegetative pathogens
-must be safe enough to use on skin or other tissues
Term
7 major methods of sterilization:
Definition
-incineration
-dry oven
-steam/pressure
-ionizing radiation
-gas (ethylene oxide)
-cold sterilization (chemical)
-mechanical filtration of liquids
Term
What is degerming?
Definition
The removal of microbes from a surface by scrubbing.
examples include:
-washing hands
-prepping skin for injection

*this is better than chemical action and reduces the greatest number of microbes.
Term
What is sanitizing?
Definition
Disinfection of public places/items. Reduces the number of pathogenic microbes to an acceptable level in order to meet public health standards.
Term
What are some practical concerns regarding basic microbial control?
Definition
1. Is sterilization required (to meet some public safety standard?)
2. Can the items be reused? or must they be discarded?
3. can the item withstand control methods?
4. is the method suitable for the given application? (i.e. harsh chemicals may not be acceptable for use as antiseptics)
Term
purpose of room filters:
Definition
HEPA filters can filter out pathogens and bacteria from the air.
Term
Carl Von Linnaeus
Definition
-Composed a system of classification based on observed characteristics
-Standardized naming (binomial, latin)
-defined a species as those who successfully interbreed.
Term
Modern Taxonomy
Definition
-DNA based
-Phylogenetic hierarchy
-Descending from a common ancestor
Term
What is an endospore stain used for?
Definition
Identification of clostridium and bacillus. Presence and location of endospore helps to identify the bacterium.
example:
C. Botulinum (terminal)
B. Anthracis (large and central)
Term
Factors affecting the death rate of microbes:
Definition
1. overall number of microbes
2. the type of microbes
3. Temperature & pH
4. concentration of agent used
5. mode of action of agent (is it cidal or static?)
6. presence of organic matter
Term
What is a capsule stain?
Definition
An acidic stain is used on the background and a basic stain is injected into the body of the bacteria. The halo in between is the capsule because it does not react to either acidic or basic stains.
Term
Describe cell division in prokaryotes:
Definition
-reproduce asexually (clone themselves)
-mutations cause diversity, clonal evolution takes place
-conjugation and transformation increase genetic diversity
Term
The rapid evolution of prokaryotes increases infectious disease. How?
Definition
Mutations will continue to outpace original growth of bacteria. Making it harder to fight with specific antibiotics. Which causes the thriving strain of bacteria to continue to infect a population.
Term
Cyanobacteria
Definition
-Is an ancestor of the chloroplast
-Participates in photosynthesis (Makes O2)
-Nitrogen fixation is inhibited by O2

*This bacteria may have been the very start of organelles and more complex structures.
Term
Who was Joseph Lister?
Definition
Used phenol to disinfect before surgery. One of the first to recognize the need to disinfect.
Term
Who was John Snow?
Definition
Associated known cases of cholera with water borne infection.
Term
Who was Alexander Fleming?
Definition
Came up with the idea of the magic bullet to fight disease. In this case, he discovered penicillin, which is an antibiotic.
Term
Who was Semmelweis?
Definition
He was described as the "savior of mothers." He concluded that childbed fever (infections that occurred after childbirth) could be reduced by hand disinfection.
Term
Strep. Pyogenes causes:
Definition
Causes a variety of human illnesses including:
-strep throat (pharyngitis)
-impetigo (a type of skin infection)
-necrotizing fasciitis
-
Term
Brucella abortus:
Definition
faculative intracellular parasites that are carried by animals and mostly affect animals, but can be seen in humans.
Term
Clostridium Difficile:
Definition
Causes severe diarrhea
Term
Vibrio Cholerae:
Definition
The bacteria that causes cholera
Term
Spirillum Minus:
Definition
rat bite fever
Term
Treponema Pallidum:
Definition
the bacteria that causes syphillis
Term
Haemophilis Influenzae:
Definition
the bacteria that causes meningitis
Term
Mycoplasma:
Definition
Gram + bacteria with no cell walls, pleomorphic and is part of the class of bacteria that causes walking pneumonia

*Genetically Gram +, but tests Gram - because there is no peptidoglycan.
Term
Pleomorphism:
Definition
The occurrance of two or more structural forms in an organisms life cycle.
Term
Plasmid:
Definition
DNA molecule separate from the organism that can transfer information

examples: genes, antibiotic resistance
Term
Sanger sequencing:
Definition
Also known as DNA sequencing, Sanger developed rapid DNA sequencing because he discovered that nucleotides pair in a specific way.
example: C--G, A--T etc.
Term
Plasmid:
Definition
DNA molecule separate from the organism that can transfer information

examples: genes, antibiotic resistance
Term
Sanger sequencing:
Definition
Also known as DNA sequencing, Sanger developed rapid DNA sequencing because he discovered that nucleotides pair in a specific way.
example: C--G, A--T etc.
Term
Franklin, Watson and Crick:
Definition
Credited with discovering the structure of DNA.
Term
Hershey and Chase are credited with:
Definition
discovering that DNA is the basis for heredity.
Term
Avery, McCleod and McCarty:
Definition
Said that DNA is the transforming principle. The transforming principle was first described in Griffith's work. But Avery, McCleod and McCarty expanded on this and concluding that DNA was what altered the genetics of known bacterial strains.
Term
Griffith's experiment:
Definition
Used two strains of bacteria and infected rats with it. When the two strains were added to each other their virulence was altered.

This was the beginning of discovering that DNA was transformed and was the transforming principle.
Term
Explain Hershey and Chase's experiment:
Definition
1. Mix radioactive phages with bacteria. The phages will then infect the bacteria.
2. Agitate in a blender to separate phages outside the bacteria from the cells and their contents.
3. Centrifuge the mixture so bacteria collect at the bottom of the tube.
4. Measure remaining radioactivity.

-This proved DNA was the transforming principle.
Term
The central dogma:
Definition
DNA is transcribed by RNA via RNA polymerase. RNA translates RNA code into protein via ribosomes.
Term
How are bacteria identified in general? What kind of tests could we do?
Definition
-metabolism
-shape
-arrangement
-staining
-serology
Term
What is serology?
Definition
Serology is the study of blood serum and other bodily fluids. Usually refers to antibodies in the blood created in response to infection.
Term
What is a bacteriostatic agent?
Definition
Something that inhibits but doesn't necessarily kill bacteria.
Term
Bioterrorism:
Definition
know that post 9/11, the US postal service began irradiating the mail with high voltage electron beams used to kill bacteria after bacillus antracis was found in mail.
Term
How do microbicidal agents work?
Definition
-disrupt cell wall or membrane
-prevent synthesis of nucleic acids
-alter the function of cellular proteins
Term
Microbial death rates when Microbicides are used:
Definition
-constant % of cells die over time
-not all killed simultaneously
-calculating the microbial death rates helps us to tell how long sterilization is required
Term
Methods of microbial control:
Definition
Heat: moist or dry
Radiation: high energy waves can enter bacterial cells and damage them
Filtration: removes microbes from air and liquid
Chemical: antimicrobials such as halogens, alcohols or detergents are used.
Term
Using heat as microbial control:
Definition
Generally, the higher the temperature the more likely the effect is microbicidal. The lower the temperature the more likely it is microbistatic.
Term
How are steam and pressure used for microbial control?
Definition
when high pressure and high temperature are both used, it will kill endospores.
This is also known as autoclaving.
Term
How are refrigeration and freezing used for microbial control?
Definition
refrigeration and freezing act as microbistatics.
the main exception to this is the bacteria listeria. It can survive and reproduce in a refrigerated environment.
Term
How is radiation used to control microbial growth?
Definition
Ionization can disrupt DNA and interfere with protein synthesis.
UV radiation will lead to formation of abnormal bonds (thymine dimers).
Term
Gram staining:
Definition
Gram +: Thick peptidoglycan. Stains purple with crystal violet.
Gram -: Thin peptidoglycan. Stains pink with safranin.

*older cells wont stain correctly.
Term
Acid fast staining (Ziehl-Neelsen):
Definition
Mainly used for myobacterium tumerculosis. This bacteria has a waxy outer membrane composed of mycolic acid which allows for acid fast staining. Methylene blue is used as a counterstain, so acid-fast bacilli stain bright red in contrast.
Term
What is LCMV? Recall from clinical correlates.
Definition
Lymphocytic choriomeningitis virus.
-rodent born (house mouse)
-virus is found in rodent's saliva, urine and feces.
Term
Bdellovibrio:
Definition
Gram - bacteria which enters other Gram - cells in a parasitic fashion using enzymes and a drilling motion.
Has a virus-like lifecycle
-many cells from one infection. Does not host machinery.
Term
S layer (or Surface layer):
Definition
-Layer of protein on the cell surface
-found in bacteria and archaea
-ancient cell wall structure for stability
-attachment
-virulence: prevents immune recognition and attachment to host

*used in nanotechnology: filtration/circuits
Term
3 domains of life:
Definition
Bacteria, Eukarya and Archaea
Term
Azidothymidine (AZT/ZDT), an antiretroviral:
Definition
Thymidine analog (N3 at 3')

-works as a transcriptase inhibitor
-this terminates viral replication.
Term
Translation and transcription occur at the same time in what type of organism?
Definition
prokaryotes
Term
DNA transcription:
Definition
photocopies DNA in the form of RNA.
Term
The genetic code is:
Definition
redundant and universal. this helps the organism to anticipate for transcription or translation mistakes.

ex:
UUU, UUC =Phen.
UUA, UUG =Leu.
Term
DNA translation:
Definition
1. codon recognition
2. peptide bond formation
3. translocation
Term
tRNA:
Definition
2 languages coming together and being translated. Nucleic acids combine to form amino acids. amino acids combine to form proteins.
Term
Mutations:
Definition
Are a heritable change in the DNA sequence. Not all mutations change proteins. This is because there is redundancy built into the genetic code.
Term
Horizontal DNA transfer: Transduction
Definition
Genes can be shared and transferred between organisms. This could help bacteria to encode resistance to certain drugs.
Term
Gene regulation:
Definition
the process by which information from a gene is used in the synthesis of a functional gene product.
Term
How do we control microbes in the environment?
Definition
Historically:
-drying foods
-salting, smoking, pickling
-osmotic control (sugars, salts)
-boiling
-burning
Term
Equine salmonella outbreak:
Definition
-acquired from the hospital (nosocomial)
-after disinfection, salmonella was not found.
--then 2 more cases...
Term
Sometimes microbes are _______ removed from materials but not killed or inhibited.
Definition
mechanically
Term
What is the difference between a -cidal agent and a -static agent?
Definition
cidal: kill microbes by damaging the cell

static: temporarily inhibit reproduction of microbes
Term
Variable resistance of microbes:
Definition
Highest resistance:
-bacterial endospores
-prions

Moderate resistance:
-protozoan cysts
-naked virus
-staph. aureus

Least resistance:
-bac. vegetative cells
-fungal spores
-enveloped virus
-yeast
-protozoan trophozoites
Term
Decontamination:
Definition
the mechanical removal of most microbes
Term
Sterilization:
Definition
Complete removal or destruction of all viable microorganisms. Used on inanimate objects.

*works on everything except prions.
Term
Disinfection:
Definition
The distruction or removal of vegetative pathogens but not bacterial endospores. Usually used only on inanimate objects.

examples include: UV light, heat, alcohol, bleach.
**does not guarantee all pathogens are eliminated.
Term
Methods of microbial control:
Definition
-sterilization
-disinfection
-antisepsis
-decontamination
Term
Main reasons for microbial control:
Definition
limit spread of disease. limit food spoilage.
Term
1980's canine parvovirus epidemic
Definition
-entire litters of puppies died within 24 hours
-humane society and shelters had to close
-bleach was effective but it didn't always work.
--bleach is inactivated by organic matter and the virus was surviving because of this.
Term
Pasteurization:
Definition
Use of heat to kill pathogens and reduce spoilage in food and beverages.
-Historically: 30 min @63C
-Flash pasteurization: 15 seconds @ 72C
-UHT pasteurization: 1 sec @134C
Term
Why is it important to know if an infection is viral or bacterial?
Definition
bacteria can be treated with antibiotics. Viruses cannot.
Term
Biofilm:
Definition
aggregates of microorganisms.
-2/3 of human infections are caused by biofilms which end up in IV fluids and other hospital equipment due to use of improper sterile technique.
Term
Fimbriae:
Definition
-involved in attachment and immune recognition
-uropathogenic (e.coli uses fimbriae to adhere to the urinary tract)
-primary mechanism for virulence of e.coli and staph bacteria.
Term
Spirochetes:
Definition
a corkscrew shaped bacteria.
-motile via axial filaments which are non-immunogenic
-it's corkscrew motion imbeds pathogens into the tissues
-cause diseases such as syphilis, bejel, pinta and yaws.
Term
conjugation (aka cell sex):
Definition
involves partial transfer of DNA from one cell to another.
Term
Chemotaxis:
Definition
bacterial movement
-positive chemotaxis --> movement toward a nutrient
-negative chemotaxis --> movement away from a nutrient
Term
flagella:
Definition
confirs motility to an organism. the number of flagella help in identification.
Term
Can you vaccinate after infection has occurred?
Definition
In some cases, like with rabies, the virus is slow to grow. If you are vaccinated within 5-7 days, your body will become immune.
Term
What is a neoplasm?
Definition
an abnormal mass of tissue
Term
These two anatomical regions of the cell may be bacteria incorporated into the cell, as proposed by endosymbiotic theory:
Definition
-chloroplasts
-mitochondira
Term
Are microbes typically positive or negatively charged?
Definition
most microbes are negatively charged and they will move toward positively charged nutrient sources (via chemotaxis).
Term
How are bacteria quantified in samples?
Definition
# of cfu/volume

*cfu=colony forming units
Term
What is a genome?
Definition
The genome is the total content of DNA. The blueprint for life.
Term
What is a nosocomial infection?
Definition
An infection acquired from the hospital.
Term
How does temperature affect bacteria?
Definition
Temperature alters the shape of enzymes and lipids. Therefore the working enzymes and lipids that are constituent to a bacteria must operate at a specific temperature.
Term
Microaerophiles
Definition
require low oxygen levels to survive
Term
aerotolerant aerobes:
Definition
can use oxygen, but it is not essential.
Term
faculative anaerobic organisms:
Definition
can use respiration (oxygen) but can also switch to fermentation.
Term
Aerobes:
Definition
use oxygen
Term
Anaerobes:
Definition
use of oxygen is toxic
Term
Hydrogen peroxide is broken down by what enzyme?
Definition
Catalase. 2H2O2 --> 2H2O + O2
Term
Superoxide dismutase destroys:
Definition
superoxide radicals. 2O2- + 2H+ --> H2O2 + O2
Term
In ________ different electron acceptors are used in the absence of oxygen.
Definition
fermentation
Term
This disease was first described by John Snow. It affects cell channels and transport (diffusion) systems causing dehydration.
Definition
cholera.
Term
These groups of bacteria are clonal and when plates are grown, massive evolution can occur.
Definition
colonies
Term
Pathogenesis is:
Definition
the manner in which an organism can spread disease.
Term
How can you tell if a bacteria is using the sugar in a medium?
Definition
-it produces acid via fermentation
-it changes in pH (see above)
-might also produce gas
Term
What is the transforming principle?
Definition
DNA. Bacterial DNA was separated into virulent and non-virulent. When they mixed together, the non-virulent became virulent again. This was because the genes of the cells intermingled.
Term
Describe the life cycle of bacteriophages:
Definition
1. phage attaches to bacterial cell
2. phage injects DNA
3. phage DNA directs host cell to make more phage DNA and protein parts. New phages then assemble.
4. Cell lyses and releases new phages
Term
bacteriophage:
Definition
a virus that infects bacteria
Term
How does flagellar movement differ in eukaryotes and prokaryotes?
Definition
eukaryotes: whip-like
prokaryotes: rotating movement
Term
Many cells have glycocalyx. How does this put them at risk?
Definition
Viruses also have glycocalyx with which they can bind with normal glycocalyx. This allows for viruses to bind and invade bacteria.
Term
The outer surface of many cells has a sugar coating composed of polysaccharides bound to proteins. This structure is ________, it functions as a receptor site.
Definition
glycocalyx
Term
Another name for a cell wall constructed of repeating subunits of NAG and NAMs. This cell wall is affected by Beta-lactam drugs that block NAM cross linking in growing cells.
Definition
peptidoglycan
Term
This man identified the antibiotic penicillin which produces the "zone of inhibition."
Definition
Alexander Fleming
Term
Treponema pallidum causes this disease:
Definition
syphilis
Term
Paul Ehrlich first described a "magic bullet." What did he mean by this?
Definition
Antimicrobials. These were first identified when Ehrlich used stains to identify disease causing cells and then later when he was able to kill the disease without killing the person.
Term
What is an attenuated vaccine?
Definition
A vaccine that has elements of disease causing agent which are reduced in virulence. some examples include:
-pasteurella multocida
-chicken cholera
-anthrax
-rabies
Term
What is Edward Jenner known for realizing?
Definition
Jenner realized that people who worked with dairy very rarely contracted smallpox. This is because these people were exposed to cowpox (which is less virulent than smallpox).
Jenner then vaccinated 8 year old James Phipps (he hadn't been previously exposed to either smallpox or cowpox).
Term
SOAP stands for:
Definition
subjective, objective, assessment, plan
Term
Helicobacter pylori infects:
Definition
the lower part of the stomach and causes inflammation in the gastric mucosa. (ulcers)
Term
Barry Marshall first described this bacteria which is Gram -, helical and causes ulcers because it produces urease which alters local pH and causes it to become more alkaline.
Definition
helicobacter pylori
Term
About 50% of people have helicobacter pylori colonies in their stomachs, only __% will get ulcer disease.
Definition
10-15%

*a very small percentage will also get stomach cancer.
Term
Describe the purpose of electron transport:
Definition
molecules carry electrons across the membranes of mitochondria creating a hydrogen gradient which produces energy.
Term
The most common infection in women ages 20-30. Causes an increase in pH in the vagina. This increases risk of STDs and PID.
Definition
Bacterial vaginosis
Term
What 2 bacteria can alter the flora in an environment?
Definition
-clostridium
-bacterial vaginosis
Term
What are the major groups of microbes?
Definition
-bacteria
-algae
-protozoa
-helminths
-fungi
Term
How are microorganisms isolated?
Definition
most does not grow on artificial media. must purify from a complex sample. isolation of causative agent is difficult.
Term
Chemotherapy:
Definition
Development and use of drugs to treat infectious diseases.
Term
What is serology?
Definition
the study of antibodies in blood serum to test for infection.
Term
Why was pasteurization originally invented?
Definition
to treat wine.
Term
Pasteurization:
Definition
fast, low heat which kills organisms but retains flavor.
Term
Describe cell theory:
Definition
all living things are composed of cells. All cells come from other cells.
Term
Robert Hooke discovered:
Definition
cells
Term
Archaea lack this feature of the cell wall:
Definition
peptidoglycan
Term
a good pathogen:
Definition
spreads well
Term
These "true nucleus" cells have organelles and are compartmentalized.
Definition
Eukaryotes
Term
This microbe is comprised of protein and nucleic acid. It requires a host.
Definition
A virus
Term
This type of motility is often seen in food poisoning with such microbes as listeria monocytogenes.
Definition
actin based motility
Term
This microbe grows at relatively low temperatures (allowing it to grow and multiply in refrigerators). It also disproportionately affects pregnant women.
Definition
Listeria Monocytogenes
Term
What is the name of the bacteria that causes flesh eating bacteria?
Definition
Strep. Pyogenes. It causes necrotizing fasciitis. Scarlet fever is also a complication of strep. pyogenes.

* Gram + cocci, it grows in chains recovered from surgical sites.
Term
Whooping cough is caused by:
Definition
Bordetella Pertussis
Term
How does bordetella pertussis make people sick?
Definition
Whooping cough kills cillia and they are unable to move in their usual whip-like fashion.
Term
This disease causes lipid accumulation in brain cells because lysosomes and peroxisomes are not functioning properly.
Definition
Tay-Sachs
Term
This type of agar is both selective and differential. It is selective in the sense that it contains crystal violet which kills Gram + bacteria and it will also host a variety of gram negative bacteria.
Definition
MacConkey agar
Term
What are Koch's postulates?
Definition
1. Causative agent is found in every case of disease which is not in healthy hosts.
2. Agent must be isolated outside of the host.
3. When re-introduced it must cause the same disease.
4. Same agent must be re-isolated from the infected host.
Term
Pathogenesis is described as:
Definition
the mechanism by which a disease is caused
Term
Bacteria and archaea are considered:
Definition
prokaryotes
Term
What component made wine good? What made it go bad?
Definition
good wine had yeast
bad wine had abundant bacteria
Term
This bacteria stains red on an acid-fast test:
Definition
tuberculosis (tubercle bacillus)
Term
This early epidemiologist, tracked cholera in London. He was also an anesthesiologist and the nature of gases helped him to understand how cholera spread through the population.
Definition
John Snow.
Term
Why and how would e.coli act as an indicator organism?
Definition
Poop shouldn't be in the water. If e. coli is present, other more dangerous organisms could also be present.
Term
Hospital hygiene and control of nosocomial infections is known as:
Definition
infection control
Term
What is etiology?
Definition
the study of the cause of diseases
Term
What is epidemiology?
Definition
frequency, distribution and spread of diseases
Term
This deltaproteobacteria is Gram - and forms a community of reproductive structures when food is limited. It's survival structure is called a myxospore.
Definition
Myxobacteria
Term
-stains lysosomes red
-used as a general stain and as a counter stain
-added to growth media for bacteria and cell cultures
-acts as a pH indicator changing from red to yellow between pH 6.8-8.0
Definition
neutral red
Term
What does each letter stand for in the DAMN NIT classification of disease?
Definition
Degenerative
Anomaly
Metabolic
Nutritional
Neoplastic
Inflammatory/Infectious
Traumatic/Toxic
Term
Eukaryotes with both filamentous and cellular forms.
Definition
Fungi
Term
A drug is:
Definition
A chemical that alters physiology in any manner.
Term
Drugs that act against diseases and drugs that are used for treating infections are known as:
Definition
chemotherapeutic agents
Term
A substance produced by natural metabolic processes of some microorganisms that can inhibit or destroy other microorganisms.
Definition
Antibiotic
Term
In the 1900's, 1/3rd of all children died of infectious diseases before the age of 5. Ehrlich termed the use of the word chemotherapy and popularized the concept of the magic bullet. This is the history that led to the discovery of:
Definition
antibiotics
Term
Semi-synthetic antimicrobials:
Definition
These antimicrobials are made by altering the chemical structure of antibiotics. They are often more effective and lost longer and also usually easier to administer.
Term
Synthetic antimicrobials
Definition
antimicrobials that are completely synthesized in the lab.
Term
What is the Kirby-Bauer method?
Definition
It is a test in which antibiotic-impregnated wafers are inserted into cultures of bacteria to test which bacteria are susceptible to which antibiotics.
Term
Why is it important to distinguish the stages of infectious diseases?
Definition
All diseases move through the phases differently and therefore we can differentiate which disease an individual may have based on when and how the signs present themselves.
Term
Stages/phases of disease:
Definition
1. incubation (no signs)
2. prodromal (vague)
3. illness (severe)
4. decline
5. convalescence (no signs)
Term
What is a reservoir?
Definition
a site where pathogens are maintained as a source of infection. (ex: animal, human or non-living)
Term
Zoonoses
Definition
diseases that are naturally spread from animal to host to humans.
via --> meat eating, blood sucking arthropod vectors.
*Usually humans are the dead end.
Term
Human Carriers:
Definition
Are infected asymptomatic individuals who can infect others. Some will eventually become ill. One major example is Typhoid Mary.
Term
How is disease transmitted?
Definition
via vector, reservoir or portal of exit (fecal-oral). fomites: objects that carry infection transiently (ex: towel, toothbrush)
Term
What is a nonliving reservoir?
Definition
a reservoir that is in the soil, water or food.
-microorganisms often contaminate dirt or water by feces or urine.
*this is relevant because smallpox can survive in a nonliving reservoir.
Term
What is epidemiology?
Definition
The study of where and when a transmission occurs in populations. Epidemiology takes into account both incidence of new cases and prevalence (or number of cases).
Term
Types of nosocomial infections:
Definition
exogenous: acquired from health care environment
endogenous: pathogen arising from normal microbiota due to health care setting
latrogenic: via catheters, surgery
Term
Non-specific defenses (immunology)
Definition
1. skin, mucous membranes, chemicals
2. phagocytosis, complement, interferon, inflammation, fever
Term
1st line of defense (skin):
Definition
the skin is both a barrier with constant turnover and it also has a chemical component with salt, lysozyme and sebum (low pH).
It also has dendritic cells which participate in antigen presenting.
Term
What are exotoxins?
Definition
toxins secreted by an microorganism. Can cause major damage to host system.
Term
What is the definition of an infection?
Definition
Invasion of the host by a pathogen.
Term
Describe the process of adhesion:
Definition
Microorganisms attach to cells required to establish colonies.
-Adhesins: ligands typically found on fimbriae, flagella
-block to prevent infection
Term
Toxoplasmosis:
Definition
caused by toxoplasma gondii.
-apicomplexan protozoan
-oocysts are 10-13 micrometers
-it is an intracellular parasite
Term
What is hemozoin?
Definition
a pigment produced by plasmodium from digested host's hemoglobin. This pigment is used to identify malaria in RBC's.
Term
What are the major complications of malaria?
Definition
-neurological damage (cerebral malaria)
-headache, psychotic convulsions, coma, fever of over 108F
-pulmonary edema
-algid malaria (systemic shock)
-blackwater fever (as evidenced in the urine)
Term
Diagnosis and Treatment of malaria:
Definition
-based on the clinical signs
-parasite found in peripheral blood smear
-stain/fluorescent dye
Term
Malaria is transmitted by:
Definition
the bite of an infected anopheles mosquito
Term
What is the relapse period for malaria?
Definition
-could happen weeks, months or years later
-p. vivax & p. ovale reoccur due to dormant hypnozoites in liver cells.
Term
Anemia period of malaria:
Definition
Massive destruction of RBC's, varies by species of malaria but p. falciparum is the most severe.
Term
Inflammatory response period of malaria:
Definition
malaise, muscle pain, headache, loss of appetite, chills, teeth shatter, bed shakes, fever, copious persperation (104-106F), recovery phase (weak, exhausted)
Term
What is the pathogenesis of malaria?
Definition
1. inflammatory response
2. anemia
3. relapse
Term
What is the incubation period of malaria?
Definition
between 10 and 4 weeks (~2 weeks)
Term
P. Knowlesi
Definition
Rare form of malaria often mistaken for P. Malariae
-More common and severe
-fever every 24 hours
-common in SE Asia
-Reservoir: Macaques
Term
P. Ovale
Definition
A very rare strain of malaria also known as "mild tertian malaria."
-found in the tropics, W. Africa, India, Vietnam, Philippines
-Fevers every 48 hours
Term
P. Malariae
Definition
"Quartan Malaria"
-Found in Africa, India, Europe, Brazil, Panama
-Seen in chimps
-~7% malaria cases
-less parasitemia
-fevers every 72 hours
Term
P. Falciparum
Definition
"Malignant tertian"
-most virulent
-50% of cases
-tropics/subtropics
-increased parasitemia
-fevers every 36-48 hours
Term
P. Vivax:
Definition
"Benign tertian malaria"
-found mostly in Asia
-43% of cases
-early onset fevers, every 48 hours.
Term
Malaria is part of a group of parasites called:
Definition
apicomplexa
Term
What are the routes of parasitic infection?
Definition
-eyes
-respiratory tract
-skin
-sex
-vector borne
-fecal/oral
Term
Why could Westernization increase incidence of parasitic disease?
Definition
for example, when westernized societies construct artificial damns on rivers they become stagnant which increases the risk for parasites.
Term
List two major concerns associated with parasites in general:
Definition
1. They cause the most common opportunistic infections in AIDS patients.
2. They cause lyme disease (which is transmitted by ticks)
Term
What are some important facts about humans and parasites?
Definition
1. Humans can be infected with more than 100 parasites. These include flagellates, amoebas, ciliates, worms and lice.
2. Some parasites host other parasites (hyperparasitism)
Term
On parasitic diseases:
Definition
There are more parasitic than non-parasitic organisms that can cause disease. Organisms that are not parasites usually host the parasite.
Term
What are some exceptions to Koch's postulates?
Definition
1. Some pathogens can't be cultured
2. Some diseases are combination and can be caused by multiple pathogens.
3. ethical problems
Term
What are Koch's postulates?
Definition
1. Isolate
2. purify culture
3. must cause the same disease
4. purify the culture again
Term
What is germ theory?
Definition
The theory that a disease is caused by infections of pathogenic organisms.
Term
What does the term etiology mean?
Definition
Etiology is the study of disease
Term
What is a syndrome?
Definition
A group of symptoms and signs that characterize a disease or abnormal condition.
Term
What is a "sign," in terms of diagnosis?
Definition
An objective manifestation of disease that can be observed or measured by others.
example: elevated blood pressure.
Term
What is a "symptom," in terms of diagnosis?
Definition
A subjective characteristic of disease felt only by the patient.
example: itchiness, pain, malaise etc.
Term
When an invading pathogen alters normal functions of the body. That person would be said to be suffering from a:
Definition
disease.
Term
What are some examples of specific immunity?
Definition
antigens such as epitope target a specific area or shape. hapten is a small molecule not recognized but can be complexed. for example: penicillin.
Term
What does Gamma interferon do?
Definition
Stimulate phagocytic activity of macrophages and neutrophils.
Term
Describe the interferon system:
Definition
Infected cells release interferon. This is then sensed by adjacent cells. This shuts down protein synthesis temporarily.
Term
What are the lymphocytes involved in specific defense?
Definition
B cells, T cells and NK cells
Term
How do antibodies work?
Definition
Antibodies are shaped like a T and thus have 2 binding sites on each end. Antigens then bind to each end facilitating agglutination.
In opsonization cells are marked so that antibody cells know to phagocytize them.
Term
What does the antibody IgG do?
Definition
comprises 85% of serum antibody. Can cross the placenta and enter the tissues.
Term
What does IgM do?
Definition
It is the primary response to antigens. It has a structure that is extremely efficient at agglutination.
Term
How are chicken pox and shingles related?
Definition
Chicken pox can cause shingles and vice versa. varicella-zoster virus.
Term
Symbiosis:
Definition
2 organisms living together.
Term
Mutual commensalism:
Definition
one organism benefits while the other is not affected.
Term
Parasitism:
Definition
one organism benefits while the other is harmed.
Term
What are resident microbiota?
Definition
Part of the normal microbiota throughout life. Most are commensal.
Term
Transient microbiota:
Definition
Remain only hours or months. Cannot persist in the body due to competition, defenses, chemical or physical changes.
Term
How do opportunistic pathogens work?
Definition
1. Normal microbiota can cause disease under certain circumstances
2. Conditions provide opportunity for pathogens.
-immune system suppressed
-intro into unusual site
-changes in normal microbiota
Term
How are microbiota acquired?
Definition
-womb is microorganism free
-microbiota develop during the birthing process
-much of one's resident microbiota established in the first year.
Term
What do IgE's do?
Definition
release histamine (allergic reaction)
Term
Contamination (pathogen entry)
Definition
presence of microbes in the body. This is NOT an infection, rather, it simply describes that the microbes are there.
Term
IgA's are found in:
Definition
milk, tears, GI and urinary tracts
Term
Infection results when:
Definition
an organism has evaded the body's external defenses, multiplied and became established.
Term
Pathogenicity vs. virulence:
Definition
the ability of the pathogen to produce infectious disease is the pathogenicity. virulence refers to the degree in which it is in the bloodstream.
Term
CD glycoprotein:
Definition
specific glycoprotein used to distinguish cell types.
example: HIV targets CD4 T cells.
Term
Macrophages
Definition
target invaders and are found throughout the body. Act as scavengers in the first line of defense in active defense and diapedesis.
Term
Mucous membranes as first line of defense:
Definition
provide a minor barrier, high turnover, trap organisms with cilia which move invaders up and out. Lysozyme is also found in the nose and eyes.
Term
What is the agent, transmission, occurence, symptoms and treatment given for shigella?
Definition
agent: shigella sonnei, flexneri or dysenteriae type 1
transmission: fecal oral, food borne
occurrence: 165 M cases, 1 M deaths
symptomps: watery, bloody diarrhea, abdominal pain, fever, vomiting
treatment: supportive antibiotics
Term
How does inflammation and fever influence our defenses?
Definition
Inflammation and fever increase antibodies, increase phagocytosis and increase interferon activity.
Term
Eosinophils:
Definition
elevated levels indicate parasitic infection and allergies. Eosinophils release toxins and RNAase to combat viral infection.
Term
Neutrophils:
Definition
When elevated are an indication of bacterial infection. They are phagocytic.
Term
What is the epidemiology of toxoplasmosis?
Definition
it is cosmopolitan in the human population. It causes complications in immuno-suppressed patients and pregnant women. It is found in feral and exotic cats as well as undercooked meat.
Term
Acute signs of toxoplasmosis:
Definition
-swollen, painful lymph nodes
-fever, headache, muscle pain, anemia, dyspnea
-rarely causes death
-often mistaken for the flu
Term
sub acute signs of toxoplasmosis:
Definition
extensive lesions in the lungs, liver, kidneys, heart, eyes and brain.
Term
Cell mediated immunity:
Definition
defense against intracellular pathogens and abnormal host cells. Does not involve antibodies. (More in notes)
Term
Herd immunity:
Definition
When a vaccination creates disease resistance among a population that is sufficient to limit spread of disease.
Term
Major histocompatibility complex (MHC):
Definition
The basis of self recognition in organ transplant. MHC's hold antigens for presentation to T cells.
Term
T lymphocytes:
Definition
cell mediated immune response. they have a unique t-cell receptor specific to the antigen.
-cytotoxic T's
-helper T's
Term
B lymphocytes:
Definition
make antibodies. There are 300,00 identical receptors per B cell. Each receptor recognizes only one antigen.
Term
lymphatic system:
Definition
immune cells are produced in the bone marrow. they then differentiate into b cells (marrow) or t cells (thymus). lymph nodes then collect cells and then spleen filters the blood.
Term
What is the body's second line of defense?
Definition
-blood stem cells in bone marrow
-variety of other cells such as lymphocytes and antibodies.
Term
lymphocyte editing:
Definition
B/T receptor shapes are randomly generated for self recognition.
Term
Detergents:
Definition
Act as a germicide because they act as surfactants. They must be cationic to be most effective. (quaternary ammonium or "quats"). They work by disrupting the cell membranes.
Term
Alcohol as a germicide:
Definition
Denatures proteins. Disrupts cytoplasmic membranes.
-70-90% used (full strength alcohol is not effective)
-20 minutes
-damages plastic, rubber
Term
phenols as germicide:
Definition
Denature proteins, disrupt cell membranes. Have low toxicity and are therefore less effective against spores.
*pseudomonas has been found in chlorhexadine.
Term
Halogens as germicide:
Definition
highly effective disinfectant and antiseptic.
-betadine scrubs
-inactivates enzyme by oxidation
Term
aldehydes as germicide:
Definition
-causes cross linking of membrane proteins
-disrupts enzyme function
-fast acting, high level disinfectant
Term
Ethylene oxide (gas sterilization) as germicide:
Definition
-blocks DNA replication
-slow acting
-very explosive
Term
hydrogen peroxide as a germicide:
Definition
-relies on direct/indirect actions of oxygen.
-free radical formation is toxic.
Term
What are some complications associated with chicken pox?
Definition
shingles, secondary infections, invasive groupA strep disease, organ dissemination, pneumonia, reyes syndrome, congenital vericella syndrome.
Term
Heavy metals as germicide:
Definition
arsenic, zinc, mercury, silver and copper. All of these elements combine with S atoms in cysteine molecules which results in an altered and non-functioning protein shape.
Term
Diagnosis and treatment of chickenpox:
Definition
clinical, serological and supportive.
-or vaccine vZIG.
Term
chronic signs of toxoplasmosis:
Definition
-host immunity builds up and suppresses tachyzoites
-tissue cysts lie dormant
--if ruptured cause intense hypersensitivity, inflammation
*chronic encephalitis, epilepsy, paralysis, retinal damage
Term
congenital toxoplasmosis:
Definition
-mother contracts while pregnant
-mostly in 3rd trimester
-causes mental retardation
-subclinical form can become active
*most common congenital abnormality in the US.
Term
transmission of toxoplasmosis:
Definition
-raw or undercooked meat containing cysts
-ingesting oocytes from cat feces/soil
-flies, cockroaches, earthworms
Term
sings and symptoms of chicken pox (vericella-zoster herpes virus):
Definition
fever, malaise
macules --> papules --> vesicles --> postule --> crust

*shingles (15-20%)
Term
Transmission of chickenpox:
Definition
-10-28 day incubation
-respiratory or vesicle skin break
-infectious 1 day before rash and during symptoms
-highly infectious
--75% transmission rate
Term
Pathogenesis of chickenpox:
Definition
respiratory --> lymphatic --> skin, respiratory and nerves
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