hackney test three
Terms
undefined, object
copy deck
- Antimicrobial agents
- agents that kill microbes or inhibit their growth.
- Sterilization
- removal or destruction of all forms of microbial life
- commercial sterilization
- exsposure to sufficient heat to kill spores of Clostridium botulinum
- santitization
- reduction of microbes presents to a safe levels
-
microbicidal agents:
bactericidal agents - kills bacteria
- fungicidal agents
- kills fungi
- virucidal
- kills viruses
- microbistatic agents
- effect is temporary and growth resumes when agent or microbes are removed
- disinfection
- destruction of vegetative pathogen present
- Asepsis
- absence of microbes from an area
- identify three different approaches in controlling the growth of microbes.
-
1.to prevent spoilage of food.
2.to prevent microbes from causing disease.
3.to prevent microbial contamination and undesirable alteration of materials. - list the following according to their resistance to antimicrobial agents.1.envelope viruses 2.naked viruses 3.endospores 4.typical vegetative bacteria 5.mycobacteria 6.prions
- prions-endospores-mycobacteria-vegetative bacteria-naked viruses-envelope viruses
- what is the ideal concentration of an antibacterial agent?
- least amount of concentration it takes to kill the microbes
- explain how the following affect the action of chemical agents a. washing and scrubing
- reduces # of microbes especially with foam disinfectant after you wash your hands
- b. heat
- is microbicidal: it increases activity
- c.organic matter
- combines with some agents reducing activity
- list two physical methods of control that are microbastatic
- cold and desiccation (drying)
- identify three targets of physical and chemical agents
- 1.plasma membrane: 2.cell proteins:(enzymes are particularly sensitive)3.nucleic acids: (result in disrupted function and death).
- compare the action and exposure of steam heat and dry heat.
- 1.steam heat is high temp. high presure. dry heat is high temp. longer exposure.
- describe the typical conditions for sterilization using the steam autoclave.
- uses pressurized steam for sterilization typical conditions are 15 psi. (steam presure), 121 degrees C for 15 minutes.
-
define the following terms
1.pasturizations. - using high temp. to kill all pathogens in foods. A disinfectant process.
- 2. equilevant treatment
- methods using different exposure or dosages and getting the same results
- 3. thermal death time
- minimal time required to kill all pathogens in liquid suspention at a given temp.
- 4. decimal reduction time
- time required to kill 90% of bacteria at a given temp.
- 5. ionizing radiation
- x-rays, gamma rays, and high energy e-
- 6. filtration
- a porous barrier used to remove microbes from liquid
- 7. desiccation
- removal of H2O is microbistatic
- membrane filters
- used to remove bacteria and viruses from fluids can sterilize heat-sensitive fluids.
- HEPA filters
- cleans the air used in OR's or homes.
- lyophilization
- dried microbes used for storing
- Describe three pasturazation techniques
- 1. Classic method= 63 degrees C for 30 minutes. 2.(HTST)(high temp. short time 72 degee C for 15 seconds 3. ultra-high temp. 140degree C for less than a second.
- discribe how high pressure kills microbes and how it is used to control their growth.
- high presure will alter proteins by denaturing and kills microbes when in conjuction with heat example: autoclave
- identify the groups of germicides to which the following belong, the action and use of each. 1)ethyl alcohol:
- group:Alcohol action:denature proteins use:solvant: disinfect instruments and degerming skin.
- 2)hexachlorophene
- group:phenolics action: denature proteins and damage membrane use:standard for new agents. use:(bisphenol) effective antibacteria in phisohex (only in prescription)
- 3)lysol
- group:phenolics action:denatures proteins and damages membrane. use:disinfectant of surfaces.
- 4)tincure of iodine
- group:Halogen action:altered proteins, except slower. use;antiseptic used, but not much anymore because too iritating.
- 5)betadine
- group:Halogen (iodophor) action:alter proteins use:antiseptic for skin and less iritating.
- 6)chlorine gas
- group= Chlorines: these fall under Halogens: action=alter proteins use=used to disinfect water supplies
- 7)chloroseptic
- group= Phenolics action= denatures proteins use= throat spray,and anticeptic for surgery
- 8)hypochlorites
- group=Halogens action= alter proteins use=disinfect restrant equipment and swimming pools.
- 9)clorox
- group=Halogens action=alter proteins use=kills HIV and HBV
- 10)silver nitrate
- group=Heavy Metals action=alters proteins at intermediate level use=AgNo3 was used in babies eyes at birth but was replaced with antibiotic salve that inhibits Chlamydia
- 11)copper sulfate
- group=Heavy metals action= alters proteins use=copper sulfate is algicidal
- 12)zinc oxide
- group=Heavy Metals action=alters proteins use= zinc oxide used as antifungal agent in paints
- 13)ceepryn
- group=QUATS QUATS is a low-level antibacteria more effective against gram + bacteria action= damage surface membranes use=antibacterial in mouth wash and contact solutions example:CEEPRYN in cepacol mouthwash.
- 14)triclosan
- group=Phenol action=denatures proteins and damages membranes use= antibacterial agent in soaps
- 15)formalin
- group=Formaldihyde that falls under Aldehydes action=alters proteins use=preserve specimens and as an embalming fluid
- 16)glutaraldehyde
- group=Alderhyde action=alters protreins use=sporocidal at extended exposures
- 17)chlorhexidine
- group=Biguanidines action=damage membrane use=contacts-surgical hand scrub-preoperative skin prep.
- what is cold sterilization?
- ionizing Radiation=action=produces high-energy ions called free radicals which react with DNA and other components killing microbes.used to sterilize plastics and other items killing microbes to preserve foods.