test number 2 Flashcards
genotype
the specific set of genes that an organism possesses
phenotype
the collection of all observable characteristic due to gene expression
pointmutation
one purine base replaced for another or one pyrimidine base replaced with another
(A&G) or (C&T)
frame shift mutation
one or two base pairs are inadvertently deleted from sequence
a break in one of the dna sequence
addition of deletion of bases
resistant mutation
a mutation that allows a microorganism to resist a certain pathogen, MO, chemical or antibiotic
spontaneous mutations
mutations arising from chance events in the environment
induced mutations
controlled lab experiments
transformation
transfer of plasmids (naked DNA) from one cell to another Live R- survive Live S- death Dead S- survive Live R+ Dead S- deaths
conjucation
occurs between related genera in the same family, transfer of plasmids over a period of contact
transduction
bacteriophage carries genes from one bacteria to another
transcription
mRNA takes opposite base pairs from DNA and gets them ready for translation
translation
3 base pairs from the mRNA are translated into 1 amino acid in the ribosome
gene must be _____ in order for it to produce a gene
activated
Termination sequence for translation is formed in the
DNA templete
antiseptics
used on tissues, used to eliminate MOs and are milder than disinfectants
disinfection
eliminates all or many pathogens in the inanimate objects with the exception of spores
less lethal than sterilization
high level disinfectants
kills spores (chlorine dioxide, H2O2) used with issues of contamination
intermediate disinfectants
does not kill spores but will kill M. Tb, fungi, (alcohol, chlorine)
low level
does not kills spores, TB, viruses, or fungi
sanitation
reduces the numbers of microorganisms on inanimate objects and in the environment to a safe level as judged by public health standards
decontamination
presence of disease producing microorganism
degermination
removal of transient MOS of the skin by mechanical or chemical means
antimicrobial agent
anything that kills or interferes with MOS (antibiotics, disinfectants, UV, intense heat)
critical instruments or devices
risk of acquiring infection if the item is contaminated is high
ex. needles, scaples, transfer forceps, cardiac catheters, implants
semi critical instruments
do not penetrate body cavities
urinary catheters, optic endoscopes
non-critical instruments and devices
face masks, electrodes, x-ray machine
soil
interfering matter ex. feces, blood, saliva, perspiration, urine
thermal death point
the lowest temperature which all mos are killed in 10minutes
time of exposure
in heat treatments longer exposure will compensate for longer exposure time
concentration of disinfectant
more concentrate = shorter killing time
less concentrate= may be bacteriostatic
microbial resistant
spores, TB, vegetative fungi, very resistant
pasteurization
physical method of disinfection destroys vegetative forms while preserving palatability of liquid
ultra pasteurization
134 C in less than 1 second
ultra sterilization
140 C for second- affects the taste
refrigeration
decreases microbial metabolism growth and reproduction
dessication
inhibits microbial growth because metabolism requires water
lypholization
combines freezing and drying for a few minutes
filtration
used for materials that cant be autoclaved
uses a millipore filter
non ionizing radiation
UV/infrared does not penetrate solidds, only disinfects surfaces
ionizing radiation
X-rays/ Gamma rays
changes the structure or chemistry of mos
Halogens
Fluorine, Bromine, Chlorine, Iodine
chlorine
liquid or gaseous
oxidation of enzymes
water treatment and disinfects inanimate objects
(Bleach)
Iodine
alternative to pure chlorine in treating water, cleaning wounds, and skin, long lasting
tincture of iodine
one of the oldest and most effective, low to intermediate level of disinfectant
more reactive than chlorine
used for wounds, and plastic instruments
inactivated by soil
Iodophors
betadine or providone
complexes of iodine or detergent soap
long lasting, non-staining, and non-irritating
used for wound treatment, skin, water, and inanimate objects
phenol
action: coagulates proteins, disrupts cell membranes
used: skin, surgical germicide
not used, high cost, odor, has effects on skin
phenolic derivates- cresols
greater germicidal activity and low toxicity
produced from coal tars
can be mixed with soap
used for environmental surfaces, non critical instruments
hexachlorophene
used commercially. clinically, and at home
used in the 50s and 60s in toothpaste, deodorant, and bath soap
PHisophex- neurotoxic to infants
bacteriostatic, used to control staph and strep
Biguanides
similar in structure to hexachlorophene but not phenol
controls microorganisms on skin and mucous membranes especially MRSA
combined with a detergent or alcohol used as a surgical scrub or wash
Chlorhexidine, Hibiclens, Hibitane
trislocan
added to soaps/ cosmectics/ broad spectrum
heavy metals
high atomic weight, contains either an inorganic or organic compounds found in form of liquids, tinctures, ointments, or soaps
may be toxic or cause allergies
Mercury
skin disinfectants, antiseptics, preservatives, very weak antiseptic, used in cosmetics and eye drops
copper
active agains chlorophill containing organisms, used in swimming pools, aquaria, 1pt/million of water, prevents mild dew in paints
metallic silver
incorporated into catheters, prevents UTIS, venous stasis graft, IVs, surgical site, cavity and tunneling wounds.
colloidal silver
mild germicidal agent in ointments or rinses for the mouth, nose, eyes and vagina
zinc
calamine lotion (zinc oxide + ferric oxide) mouthwash (zinc chloride) antifungal in paints (zinc oxide)
organic solvents
bactericidal, fungicidal, virucidal but not sporocidal
alcohols
uses: skin, instruments, 70% most effective concentration for antimicrobial
effective for tb
ethyl and isopropyl alcohol are the only ones appropriate for microbial control
alcohol is also used to enhance what chemical products?
Zephiran
Aldehydes
actions: reacts with amino and hydroxyl groups in nucleic acids and proteins
uses: cool sterilizing for instruments
unstable/ toxic dilute 1-2%
formaldehyde
used as a preservative
gas form and suspended in water
penetration is poor
used in shampoo and adhesives to sterilize and to disinfect imported fabrics
ethylene oxide
gaseous steralint , sterilizes plastics, catheters, sutures, electronic equipment, mattresses, pillows, heart/lung machines, artificial heart valves, dried or powdered foods
must be mixed wiht CO2 or N2
explodes when mixed with air
highly penetrating and slow acting
proplyene oxide
gaseous stimulant
sterilzation of nuts, powders, starches, and spices
beta propiolactone
similar to ETO. rapid microbial
sterilizes bones and artificial grafts
glutaraldehyde
form of formaldyhede
rapid and broad specrum sterilant
stays good in inorganic matter
used to clean machines
hydrogen peroxide
rinses wounds, scrapes, abrasions, and anaerobic infections
foams and H2O2 is broken into O and water by the catalases in tissues
used for soft contact lenses, utensils, heat sensitive plates, surgical implants
ozone
highly reactive form of o2
disinfection of air and water, used in industrial ACs and cooling towers
supplements chlorine and disinfection of water
neutralizes tastes and odors
peracetic acids
most effective liquid chemical sporocidal agents
leaves no toxic residue
minimally affected by presence of organic matter
effective for endospores and viruses for 30 minutes
kills vegitative bacteria and fungi in 5 minutes
used to sterilize rooms and space shuttles
soap
fatty acid combined with potassium or sodium hydrochloride
PH= 8
not antimicrobial
mechanical washing of skin surface
wetting agents, emulsifies and solubilizes particles clinging to surface
detergent
synthetic chemicals developed for their ability to be strong wetting agents and surface tension reducers
induces leakage from cell membrane
quaternary ammonuim compounds (quats)
not sporocidal
used to disinfect floors, walls and furniture
fungicidal, amoebocidal, virucidal
qualities of an ideal disinfectant
destroys all forms of mos in a practical period of time
nonirritating to tissues; nonallergenic, non toxic
soil does not interfere with its action
leaves no residue
would make effective contact
chemically stable
effective range not easily bypassed by diluting
no disagreeable odor, no stains, inexpensive
phenol coefficients
the standards of effectiveness (phenol)
if higher than 1 more effective than phenol
if lower than 1 less effective than phenol
dilution
cylinders dipped into bacteria dry at 37 C and immersed in disinfectant for 10 minutes then incubated for 48 hours
antibiotic syngerism
combination of 2 antibiotics that have enhanced bactericidal activity when properly tested together
antibiotic antagonism
one antibiotic interferes with the killing action of another antibiotic
beta lactamase
an enzyme that breaks down the beta lactamase ring in penicillins.
hydrolysis of the ring protects bacteria from the antimicrobial action of the antibiotic
prophylaxsis
use of antibiotic for a “just in case” situation
superinfection
destruction of benefical MOs that allows resistant MOs to over grow
5 mechanisms of action for antibiotics
inhibition of cell wall synthesis alteration of cell membrane inhibition of protein synthesis inhibition of nucleic acid synthesis inhibit general metabolic pathways;block pathogens recognition of attachment to host (folate metabolism)
Inhibition of cell wall synthesis
blocks synthesis of intact peptidoglycan by preventing cross linkages
cell walls are less resistant to osmotic pressure
attacks only growing bacterial cells
doesnt attack human cells because they have no peptidoglycan
Drug classes of drugs that block cell wall synthesis
Penicillins Cephalosporins Carbapenems monobactams combination drugs vancomycin bacitran ethamnbutol TB drugs
penicillin G
Inhibition of cell wall synthesis
occurs naturally, acid sensitive, narrow spectrum
semisynthetic penicillin
Inhibition of cell wall synthesis narrow spectrum, good absorption
amoxicillin, ampicillin
Inhibition of cell wall synthesis broad spectrum
nafcillin, methcillin, oxacillin
Inhibition of cell wall synthesis
treat penicillinase producing MOs
cephalosporins
Inhibition of cell wall synthesis same action as penicillin but wider spectrum
divided into generations based on their spectrum of acitivity
normally giving IM or IV
1st generation cephalosporin
Inhibition of cell wall synthesis similar in action to ampicillin
2nd generation cephalosporin
Inhibition of cell wall synthesis less active against G+ more active against G-
3rd generation cephalosporin
Inhibition of cell wall synthesis less active against gram + more active agains gram -
4th generation cephalosporin
Inhibition of cell wall synthesis enhanced toxicity, extended spectrum
carbapenems
Inhibition of cell wall synthesis
broad spectrum
monobactams
Inhibition of cell wall synthesis
synthetic replacement for those allergic to penicillin
crosses placenta and may lead to pseudomonous colitis
combination drugs
beta lactase inhibitor+ amoxicillin
augmentum= amoxicillin+clavulanic acid
vancomycin
Inhibition of cell wall synthesis
gram +
poor absorption
not the best but it is effective against MRSA and c-diff
avapracin
Inhibition of cell wall synthesis
used agriculturally, as a growth promoter
bacitran
Inhibition of cell wall synthesis
prevents cross links from forming in the cell wall
topically for skin ointment, caused by gram +
Tuberculosis drugs
Inhibition of cell wall synthesis
Isoniazid and ethambutol
block mycolic acid and peptidogylcan production
Isonizaid
Inhibition of cell wall synthesis
penetrates macrophages or walled off areas in the lungs
used in combination with rifampin or ethambutol
ethambutol
Inhibition of cell wall synthesis
Always used in combination and used to treat TB
Inhibition of protein synthesis
as a group, these antibiotics bind to the ribosomal subunits
drugs that inhibit protein synthesis
aminoglycosides tetracyclines chloramphenicol macrolides erythroomycins azithromycins clindamycin
aminoglycosides
Inhibition of protein synthesis
amino acids bonded to carbs
bactericail and most toxic
not absorbed orally
aminoglycosides can
accumilate in the body which can lead to future issues
streptomycin
dizziness, long term use may lead to damage of the 8th cranial nerve
gentamycin
less toxic
tobramycin
used for psuedomonas
tetracyclines
absorbed easily, take 30 min before eating, avoid antacids because they can b=hinder absorption
what happens when pregnant women take tetracyclines
yellows discoloration of children under 8
not used in pregnant women bc baby can be born with a full set of teeth
tetracyclines treat
acne, rosacea, anthrax, lyme disease
semisynthetic tetraycline have a longer
retention in the body
chloramphenicol
disrupts protein synthesis in bone marrow cells, first broad spectrum antibiotic developed, accumulates in the CSF, and crosses the blood brain barrier
can accumulate in infants system and cause toxicity (in CVS= grays syndrome)
also may cause aplastic anemia
erythromycin
bacteriostatic
cant penetrate G-B wall
used for patients who are allergic to penicillin
azithromycin
Also known as Zpack
used for STIs only 1 or 2 pills
Clindamycin
used to treat anaerobic infections caused by trauma, surgery or accidents, may cause psuedomonas colitis (C-diff)
Alterations of cell membranes
changes cell membrane permibility
drugs that change the cell membrane
Polymyxins B and E (E is used for UTIs) nephrotoxic topical ointment used to treat gram -
inhibition of nucleic acid synthesis
binds to RNA polymerase (rifampin) or inhibits DNA gyrase (quinolones)
rifampin
used in combination to treat M. TB
used for carriers of N menigitidis
structurally related to macrolides
reaches therapeutic levels in CSF and abcesses
color changes in urine, feces, saliva, sweat or tears
may be hepatotoxic
comes out a rusty color (tears sweat and urine)
why would it be necessary for an antibiotic to cross the blood brain barrier?
to treat leisons/meningitis etc…
rifampin can turn what rusty?
urine/sweat/tears and amniotic fluid
fluoroquinolones
inhibition of protein synthesis
end in cin
synthetic, similar to nalidixic acid
broad spectrum, oral, pentrates tissues well
may cause arthropathy in children, adolescents and PG women
absorption is blocked by antacids
used for patients on chemo, post surgical infections, UTIs and TB
used by chicken farmers, enrofloxacin
inhibition of metabolic pathways
prevents synthesis of folic acid
some hypersensitivities
drugs that inhibit metabolic pathways
sulfa drugs
used to control infection in burn patients
can christalize in the kidneys, have the patient drink tons of water when they take it
antifungal agents
amphotericin B Nystatin grisofulvin synthetic azoles tolnafate echinocandins pentamidine
