Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
82 Cards in this Set
- Front
- Back
|
1. what is the purpose of differential media?
2. give an example |
1. distinguishes microorganisms based on their metabolic activity
2. Simmons Citrate agar |
|
|
1. what is the purpose of the selective/differential media?
2. give an example |
1. has both selective and differential media characteristics.
2. Mannitol salt agar |
|
|
1. describe the Mannitol salt agar.
2. what organism is grown on it and why? |
1.its 7.5 % mannitol salt
2. its selective because only staphylococcus grow on it due its salt, and differentail because only S. Aureus can ferment mannitol turning plate from pink to yellow |
|
|
Which media are used for growing GRAM POSITIVE baceria
|
phenyl ethyl alcohol/ blood (PEA/PEAB)
Columbia colistin, naladixic acid (CNA) |
|
|
1.what is the medium used for Corynebacterium diptheriae?
2. what are the other variations of this medium 3. how do the colonies appear and why? |
1.Tinsdale medium (inhibits gram + and -)
2.but C. diptheriae is resistant chocolate tellurite, loefflers medium 3. black with dark gray halos because they convert tellurite > tellurium |
|
|
1. what organisms do we grow on Egg Yolk Medium
2. what is the appearance of these organisms |
1. C. Perfringens which has lecithinase activity which converts phospholipids >diglycerides.
2. diglycerides appear as zones of opalescence surrounding the colonies |
|
|
1. describe the Thayer Martin Agar?
2. what organisms do we grow on the plate and how do we distinguish them |
1. blood agar base containing antibiotics and salts
2. n. gonorrhoeae appears grayish white mucoid n. meningitidis appears blue-gray mucoid |
|
|
what agar media is used for gram negatives
|
macconkey
eosin methylene blue (EMB) Hektoen Enteric Agar Xylose lysine desoxycholate Agar |
|
|
1. what kind of organisms does Macconkey grow?
2. how does E.cloi appear on this |
1. grows gram- because of bile salts
2. e-coli ferments lactose and turns plate from orange to dark pink all of this make this a selective/differentail plate |
|
|
1. what kind of organisms does EMB agar grow?
2. how does E.coli appear of this |
1. gram- because of methylene blue and eosin.
2. E.coli ferments lactose and appears metallic green |
|
|
1.what kind of bugs do we use Hektoen Enteric Agar for and why?
|
salmonella and shigella which are gram- because it has bile salts which inhibit all gram+ and most gram - except these 2
|
|
|
how are salmonella and shigella distinguished in Hektoen Enteric agar
|
lactose fermentors will turn the plate yellow because they make acid
salmonella (nonfermenter) turns it black by reducing the hydrogen sulfide |
|
|
1. what bugs to we grow on a Xylose Lysine Desoxycholate Agar?
|
gram negative salmonella and shigella becuase sodium desoxylate prevents gram +
|
|
|
1.how are salmonella and shigella distinguished from each other on the a Xylose Lysine Desoxycholate Agar
|
salmonella engages in xylose fermentation and H2S production, and lysine decarboxylation.
sulfide from H2S reacts with Iron and makes colonies black |
|
|
1. what organism is isolated on Bordet-Gengou (BG) agar?
|
BG agar is made of Potato-glycerol based with 15-20% defibrinated blood
selective for Bordetella pertussis |
|
|
1. what organism is isolated on Buffered charcoal yeast extract agar (BCYE)
|
contains Yeast extract, charcoal and salts
Selective for Legionella sp. |
|
|
1. what is the key ingredient that we need to isolate Legionella
|
Alpha-ketoglutarate
|
|
|
1. what organism grows on Thiosulfate citrate-bile salts agar (TCBS)
|
Vibrio sp
|
|
|
1. what organism grows on Cefsulodin-Irgasan-Novobiocin (CIN) agar
2. what do the colonies look like |
1. Yersinia sp.
2. red-pigmented “bullseye” in the middle of each colony |
|
|
1. describe Lowenstein-Jensen Agar
2.what organism grows on it? |
1.Egg-based medium. Contaminants inhibited by malachite green
2.Mycobacterium sp |
|
|
1. describe the Middlebrook Agar.
2. what its advantage over Lowenstein-Jensen Agar |
1. Contains OADC (oleic acid-dextrose-citrate) enrichment which Chemically simulates egg components
2. Isoniazid-resistant strains of Mycobacterium sp grow better |
|
|
1. what organism is isolated on MES (Ureaplasma Agar)
2. why do we use this agar? |
1. Ureaplasma urealyticum
2 Contains horse serum which Supplies cholesterol needed for stabilizing them and Urea which is a required nutrient |
|
|
1. what is the catalase activity of staphylococcus and streptococcus
|
staphylococcus catalse+ streptococcus catalase -
|
|
|
1. how do we distinguish s. Aureus from others ?
|
1. perform a coagulase test, S. Aureus is coagulase +
|
|
|
1. what does the oxidase test detect ? 2 what organism do we use it for?
|
1. detects cytochrome oxidase enzyme.
2. Neisseria |
|
|
1. what does the Indole test detect ?
2.what organism do we use it for? |
1. activity of the tryptophanase enzyme on tryptophan, turning kovacs reagent red.
2. E. Coli |
|
|
1. what does the urease test detect?
2. what organism do we use it for? |
1. Detects activity of urease which hydrolyzes urea releasing ammonia urning medium from orange to pink
2. Proteus sp. |
|
|
1. what organism is detected with the Bile Esculin test?
|
Group D streptococci Enterococcus which can hydrolyze esculin a bile salt. this turns medium from orange to black
|
|
|
1. what organism is detected with the Optochin Test – P disc test?
|
Streptococcus pneumoniae because its sensitive to Optochin and will not grow around it
|
|
|
1. what organism is detected with the Bacitracin – A disc test?
|
group A streptococci from other groups of beta-hemolytic streptococci.
S. pyogenes is resistant to this |
|
|
what are some deratophyte fungi
|
Microsporum
Epidermophyton Trichophyton |
|
|
What are the steps for direct microscopic examination of Fungal diseases
|
1. treat with 10-20% KOH which dissolves everything except the Fungi
2. stain with crystal violet oe lactophenol cotton blue |
|
|
what is India Ink used for?
what do you have to be carefull of when using india ink |
1. for detection of Cryptococcus Neoformans in CSF. the bugs have a clear area around them.
2. WBC reseble c.neoformans |
|
|
1. what is Periodic acid-Schiff stain used for?
|
1. detection of fungal elements in tissue specimens.
fungi appear red |
|
|
1. what is Grocott-Gomori methenamine-silver nitrate stain
used for? |
1. to stain fungi such as Candida, Histoplasma, Blastomyces.
fungi appeak black |
|
|
what is Giemsa stain used for
|
Detects Histoplasma capsulatum in blood or bone marrow
Stains yeast a purple-blue surrounded by clear halo |
|
|
what is Masson-Fontana stain used for
|
Stains melanin in the cell wall of fungi a brown color
|
|
|
what is Phospholipid ester-linked fatty acid analysis PLFA used for?
|
Can be used to identify groups of microorganisms through their phospholipids, and microrganism viability.
|
|
|
1.what is the role of crystal violet
2. what is the role of grams iodine 3. role of 95 etoh 4. what is the role of safranin |
1. primay stain- stains everything purple
2. mordant- locks in he color 3.de-stains gram- 4. counterstain, gram- (pink) gram+ purple |
|
|
1. for what organism do we use a Acid Fast- Akaziehl-neelsen for?
2. what dye do we use in this stain? why? 3. what are the de-stainers and counterstains used for? |
1. mycobacterium Sp.
2. carbol-fuschin red because its lipid soluble 3. de-stainer: acid alcohol. counter stain: methyl blue |
|
|
1. what is a differential stain?
2. what kind of medium do we use for this? 3. what are the dyes we use with this? 4. how will the organism appear |
1. looks for extracelluar capsule
2. skim milk medium 3. congo red, crystal violet 4. unstained capsule appears as a halo |
|
|
1. what stain is used for flagella?
2. what dye is used spores? 3.what is used as counterstain for spores |
1. liefson's
2. Malachite green for endospres 3. Safranin for vegetative bacteria |
|
|
1. what is B-hemolysis
2. name 2 bacteria that do this |
1. leaves clear areas around colony
2. S. Pyogenes, S. Aureus |
|
|
1. What is a-hemolysis
2. what is an an example of an microorganism that does this? |
1. leaves green areas around colonies
2. S. Pneumoniae |
|
|
1. what is selective media?
2. give an example of selective agent |
1. favors growth of one kind of microrganism over other
2. dyes, antibiotics, |
|
|
what is the key factor of type I hypersensitivity
|
its immediate
|
|
|
1.what kind of antigens for type 1.
2.what kind of cells respond to this antigen ? 3.what is the effector mechanism |
1.soluble antigen
2. Th2 B-cells 3. mast cell degranulation when exposed to the same antigen a second time |
|
|
what are some examples of Type 1 hypersensitivity rxn
|
allergic rhinitis
asthma systemic anaphylaxis |
|
|
what cytokine does a Th2 differentiation need
|
IL4
|
|
|
where are mast cells made and where do they mature.
where are mast cells typically found? |
made in B.M, Mature in tissues
near blood vessels, nerves, and beneath epithelia |
|
|
what is the mast cell receptor that binds to IGE? and how tight is this bond?
|
FceRI, and its so tight they are considered one molecule
|
|
|
what are the 2 steps in the release of mast cells products
|
1. they release the granules they have
2. they make more stuff for immediate release, but not to fill granules |
|
|
what is the reaction seen to mast cells degranulation on the skin
|
Wheel and flare
wheel is the center part flare is the surrounding part |
|
|
what is the key product that is immediately released from mast cells
what are the products synthesized after the initial vesicle release |
Histmine
TNF-a, IL-3,4,5, GMCSF, LTC,D,E |
|
|
what is the role of the following things?
1. TNFa 2. IL-4 3.IL3,5, GM-CSF 4. LT C4,D4,E4 |
1. promotes inflammation
2. amplifies Th2 response 3. eosinophil production and activation 4. mucus secretion, + vascular permeability. + smooth muscle contract |
|
|
what is the role of Leukotrienes and how does their potency compare to Histamine
|
1. smooth muscle ontraction
2. increased vascular permeability 3. mucus secretion they are 10x more potent than histamin |
|
|
what cells are the basophils related to developmentally and functionally.
where are the basophils located |
functionally related to mast cells, developmentally with eosinophils
located in the blood, recruited to the tissue |
|
|
where are the eosinophils located?
what is their expansion dependent on? what kind of receptor to they express and when? |
reside in mucosal and epithelial tissue.
mast cells releasing IL-5. EceRI after they get activated |
|
|
why are eosinophils kept in low numbers?
|
because they release large amounts of peroxidase, collagenase, Major basic protein, and others which are all very toxic to the cell
|
|
|
1what are the factors released by the eosinophils after initial activation
|
1. IL3,5 GMCSF which cause bonemarrow to make more eosinophils and to activate them.
2. Leukotriene C4,D4,E4 which cause SM contraction, +vascular permeability |
|
|
what does a patient with Eosinophilia (12-24%) most likely have?
|
parasites, worms.
|
|
|
how does histamin affect the following:
1. Arteries 2. cardiac 3.Smooth muscle 4. capilary permeability |
1. vasodialation
2. stimulation 3. constriction 4. increased vascular permeability |
|
|
what are the classic type I hypersensitivity reactions
|
allergic asthma
allergic rhinitis/ hay fever food allergies insect sting allergies |
|
|
what is the meadiator for allergic asthma
what do they cause in a patient |
histamine, heparin
airway constriction, mucus secretion |
|
|
what are some factors that cause subepitheial fibrosis
|
tryptase
chymase cathepsin G carboxypeptidase |
|
|
what is the difference between viral and bacterial rhinitis
|
viral is watery while bacterial is yellow in color and thicker
|
|
|
what is the difference between food intolerance and toxicity Vs. allergies
|
food intolerance and toxicity are not immidiate.
food allergies are type1 and immidiate |
|
|
what are some of the oral allergy syndromes
|
allergic eosinophilic esophagitis
food protein induced proctocolitis food protein induced enteropathy food protein induced enterocolitis |
|
|
what is the emergent treatment of systemic anaphylaxis
what is the delayed treatment for systemic anaphylaxis |
Epinephrine
Iv fluids, anti histamines, corticosteroids |
|
|
what are the tests used to diagnose Type 1 reactions
|
Serum IgE levels
Skin prick testing for specific IgE |
|
|
what is the goal of desensitization when it comes to allergy testing
|
to induce a change from IgE to IgG1
|
|
|
what are the antibodies generated in Type II hypersensitivity.
what are they directed against |
IGM, or IgG
directed against self surface antigens or extra cellular matrix proteins. that are fixed. |
|
|
what happens when Type II hypersensitivity antibodies bind to antigen
|
1. complement of FcR mediated uptake and destruction of cells or local inflammation and tissue damage
|
|
|
what are the primary targets of for incidental drug modification like those of penicillin allergies
|
erythrocytes and platelets
|
|
|
what are the drugs that are most likely to cause drug induced Anemia or Thrombocytopenia.
|
penicillin
quinidine methyldopa |
|
|
what are some Type II hypersensitivity reactions
|
Autoimmune Hemolytic Anemia
Goodpasteurs syndrome Graves Diseases Myasthenia Gravis |
|
|
what is the target of the antibodies generated in type III hypersensitivity?
what is the problem with Type III reactions |
soluble antigens
Antigen-Ab complex is not 2 abs to each antigen so its insufficient to fix complement, so it sediments causing inflammation in vessels and tubules |
|
|
what is the antibody produced in Type III.
what ate classic type III hypersensitivity reactions? |
IgG.
Arthus reaction, serum sickness |
|
|
what is the differences between type I Hypersensitivity and Arthus reaction
|
its IgG dependant and the timing is 1-2 hours after the injection
|
|
|
how long does it take for a serum sickness reaction to show
|
7-10 days
|
|
|
1.what is the mediator of type IV hypersensitivity.
2.what kind of antigens does the body ammount an immune response to? 3. how much antigen is required for this? |
1. Th1, Th2 or CTL t-cells
2. soluble antigen 3. 100-1000 times more antigen than that required for antibody mediated hypersensitivities |
|
|
what are the classic examples of type IV hypersensitivity
|
skin responses such as:
TB skin test poison ivy type I diabetes, MS, IBS, autoimmune myocarditis, Guillian-Barre syndrome. |
