IDR lab Flashcards
Antiseptics are used when and where?
Disinfectants are used when and where?
used to kill bacteria on the external surface of the human body (Antiseptics)
used to kill bacteria on inanimate objects (Disinfectants)
What is the difference between antibiotic/antiseptic?
Antibiotics have a location/target that are specific to a cell
Antiseptics attack anything living i.e. cell membrane
Sterilization does what?
Pasteurization does what?
Sterilization reduces the living cell population to 0
Pasteurization reduces the number of bacteria to a number that is safe to deal with
Heat and radiation destroy cells how?
Alcohol disrupts membranes how?
Heat: denatures proteins, radicals cause oxidant that break and damage organisms
destroy, disrupt cell membranes
Acids and bases disrupt proteins how?
break bonds in DNA, protein folding stays at a certain pH, when changed, unfolding occurs
Disinfectants/Antiseptics are the same ____________ but administered at different ________
Where are they used?
chemical
locations
Antiseptic: used to kill bacteria on the outside of the human body
Disinfectant: used on the surface of inanimate objects
Why does box milk taste different than regular milk?
The box milk was pasteurized at a higher temperature, the taste proteins were destroyed, therefore, taste differently
Bacterial spores can be killed, how?
Autoclave, the pressured is raised
If autoclaving something is not an option, what should be used?
UV light- OR room
Ionizing radiation-plastic catheter kits
Liquid Filtration- keep all the bad stuff out
Name an advantage and disadvantage of filtration?
Advantage: will keep all solution properties intact, wont lose any necessary molecules
Disadvantage: will lose bigger molecules that may or may not be needed
Viruses need what size filter to be stopped?
0.1-0.2 um
What are two methods that count live and dead bacteria?
Hemocytomter/Petroff-Hauser counter
Spectrophotometry –> compared to McFarland Standards
What method counts only live bacteria?
Spread plate/pour plate
What things interfere Spectrophotometry?
Biofilms and Capsules, cannot use urine or sputum samples because they are all ready opaque
What interferes with serial dilution/spread plate?
Bacteria population out of range
Must be between 30 and 300
How does Iodine hurt a solution?
Free radical creation
How does Isopropryl alcohol hurt a cell?
Acetic Acid disrupts a cell how?
Messes up the membrane
Protein Denaturation
__________ are used to study the innate immune system because when they’re less than a week old, ________ have no adaptive immune system
Larval zebrafish
_______________ that have been bred to lack a thymus. They can be used to study the functioning of the immune system with no T-cells. What does these animals lack that control hair follicle growth?
“Nude” mice
No Treg
What is located in the blood plasma?
What is located in the buffy coat?
Antibodies (serum)
White Blood cells
Direct Coombs test does what?
Indirect Coombs test does what?
Mom, baby overlap
Maternal serum is incubated with Rh plus, discover matches with blood bank
____________is a derivative of immunohistochemistry, but using fluorophores attached to antibodies rather than enzymes that will undergo a color change when a reagent is added
Immunofluorescence
______________antibodies made by clones of just one B-cell, so all the antibodies have the exact same CDR/bind in an identical way to an identical epitope
Monoclonal antibody
______________antibodies against the same antigen, but where the antibody-producing plasma cells arose separately, thus the antibodies likely have different CDRs and thus different affinities for that antigen
Polyclonal antibodies
What does FACS stand for?
Fluorescence-activated cell-sorting
What two things should the skin be washed with before taking a blood sample?
70% alcohol
2% Iodine
What way can urine be obtained without contamination?
What can contaminate urine, what bacteria?
Bladder Aspirate
Lactobacillus
What test is the “Gold standard” for establishing what species microbe (bacterial or eukaryotic—not viral) is
What must you have narrowed down in order to make a decision?
Ribosomal RNA Sequencing
Bacterial section
What test shows relatedness of microbes; can be used to determine whether all isolates are the same strain/part of the same outbreak? This test does not identify particular genes
PFGE
Shows whether, at what level, microbial gene is being expressed, WB: protein, rtPCR: transcript, rtPCR can be used to quantify number of viruses with RNA genomes in patient sample?
Western Blot and RT/PCR
Does not show relatedness
What test determines whether microbe has a particular gene, does not establish whether gene is expressed, does not show relatedness of microbes to each other?
PCR
What does MIC mean? Stand for?
What does MBC mean? Stand for?
Minimum inhibitory Concentration, growth stopped
Minimum bactericidal concentration, bacteria killed
The broncho-alveolar lavage is what?
Risk of contamination reduced, but this is a more invasive technique. Only use if patient cannot expectorate sputum or if repeated attempts to collect sputum have had high levels of contamination
Hektoen enteric agar contains iron like TSI slants do, so bacteria that produce H2S (like __________ ) grow into black colonies on these plates
Salmonella
Tellurite-containing blood/chocolate agar: _________________ precipitate out tellurite, turning colonies dark brown or black. _____________ is very good at this, making colonies have a black halo as well.
Corynebacteria
C. diphtheriae
What grows well on chocolate agar? Why is this needed?
H. Flu
The bacteria lack the essential hemolysins to break down the cell and therefore cannot get proper nutrients
Very Fastidious
Eosin-Methylene Blue are necessary for what? What color will show up?
Really good showing gram negative
Metallic Green
What color does Mackoney agar turn when the bacteria ferment?
Pink
rt-PCR allows ___________ with ________ genomes to be studied using PCR, and also allows gene expression (rather than just gene presence/ absence) to be examined
viruses
RNA genomes
Mannitol Salt Agar, turns what color for acidic? The agar turns what color for basic?
Acidic –> yellow, Staph. Aureus
Basic –> red, Micrococcus Luteus
Charcoal-buffered yeast agar grows what bacteria? What does it help do?
Bordetella Pertussis
The agar helps remove the toxins from the bacteria metabolite
The MELISA test examines if the patient’s blood has what?
Memory T cells via the clonal expansion process, via a type 4 HSR reaction
What test is used now to quantify if a patient has TB? What molecule is examined?
MELISA technique, IFN gamma, T-Spot-TB test
Coombs Test is checking what?
Indirect coombs test is checking what?
Hemolytic Anemia
Indirect: serum sickness and Hemolytic disease of the newborn, mom must be Rh negative
In order of the HDNB to happen, what must be the Rh status of mom and the baby?
Mom: Rh negative
Baby: Rh positive
An _______ is an example of a precipitin test that once was used to test for production of specific bacterial toxins, by plating bacterial samples and exposing them to anti-[that toxin] antibody
Elek test
LAMP/PCR uses multiple what in order to make solution?
Multiple Primers
If the CSF has lower than 40 percent glucose, what would the results show or not show?
Bacterial or Fungal Disease
NOT viral, doesnt use up glucose, gets into someone else’s cell
What is the most commonly used automated system?
What is this system based around?
VITEK
McFarland Standards, must all ready know, gram stain, oxygen levels, must be known before testing
The time of flight is used to identify molecules via their molecular signature. What is the basis of the instrument?
Mass Spectroscopy
______________can be used to quantify number of viruses with RNA genomes in patient sample
rtPCR
Iodine affects membranes in what way?
Free radical creation
How much blood should you collect for adults, children, and neonates?
20 mL
10 mL
2 mL
Pleural, pericardial, and peritoneal fluid should or should not be exposed to the air?
Should not be
Kirby Bauer –> bacteria are susceptible or resistance to small circle number?
Bacteria are resistant
If the circle around the disk is large, the bacteria are very susceptible
Macrophage, ____________, Lymphocyte, ___________, bacteria, _________
Neutrophil
Bacterium
Virus
what is the filter size for the typical pore size?
0.1 - 0.2 um
What type of samples can we not use Spectrophotometry on?
Blood, Sputum
What is difference in the temperature via PCR and LAMP PCR?
Lamp PCR is constant, regular PCR, the levels go up and down, Lamp PCR has more primers
What color is MRSA turning?
What color is MSSA turning?
Pink
Blue
Media are selective based on what?
Osmotic Stress
Mannitol Salt Agar will not have respiratory, gut, and vaginal growth. But will have what growth?
Skin
Differential: refers to what change? with respect to an agar
Color
When a western blot goes really dark, what is wrong? How do you fix it?
Antibodies are not specific enough, put milk on it, block membrane
