| Term | Definition |
|---|
| decontamination | destruction/removal/reduction in number of undesirable microbes |
| sepsis | growth of microorganisms in tissues |
| asepsis | techniques that prevent the entry of microorganisms into sterile tissues |
| antiseptic | chemicals applied to body surface to destroy/inhibit vegetative pathogens |
| disinfection | destruction of vegetative pathogens on inanimate objects |
| sanitization | cleansing technique that removes microorganisms and debris from inanimate objects |
| degermation | removes microorganisms and debris from living tissue |
| sterilization | the removal or destruction of all viable microbes |
| mode of action | cell wall/cell membrane/nucleic acid synthesis/protein synthesis/protein function |
| agents that degrade cell wall | PCN, detergents, alcohol |
| agents that degrade cell membrane | surfactants |
| agents that inhibit nucleic acid synthesis | formaldehyde, radiation |
| agent that inhibits protein synthesis | chloramphenicol |
| agents that inhibit protein function | heat, pH, alcohols, acids, phenolics |
| physical control of microorganisms | heat, cold, desiccation, radiation, filtration |
| types of heat | moist heat and dry heat |
| types of moist heat | steam and pressure/tyndallization/pasteurization/boiling water |
| steam and pressure | temps above 100C, destroys spores, sterilizes inanimate objects (glass); ex: autoclave, steam pressure cooker |
| tyndallization | free flowing steam for 30-60 mins (canned food, heat-sensitive media); does NOT destroy spores |
| pasteurization | disinfection of beverages, kills non-spore forming microbes, lowers overall microbe count (ex: milk) |
| types of pasteurization | flash method: 71.6C X 15 sec / batch method: 63-66C X 30 mins |
| spectrum | range of activity of a drug (narrow-polymyxin or broad-PCN, TCN) |
| MIC | minimum inhibitory concentration; lowest concentration that visibly inhibits growth; for bacteriostatic agents |
| MBC | minimum bactericidal concentration; lowest concentration that kills 99.9% of the original inoculum; for bactericidal agents |
| therapeutic index | toxic dose-effective dose; greater ratio = higher index, which is preferred. |
| combination therapy | take advantage of antibiotic synergism |
| cell wall inhibitors | PCN, bacitracin, cephalosporin, vancomycin, cycloserine |
| cell membrane inhibitors | polymyxin (bacteria), polyenes (fungi) |
| protein synthesis inhibitors | TCN, erythromycin, streptomycin, chloramphenicol |
| nucleic acid synthesis inhibitors | rifamycin, quinolones |
| antimetabolites (folic acid synthesis inhibitors) | sulfanilamide, trimethoprim |
| B-lactamase | enzyme that breaks down B-lactam ring in PCN, rendering it ineffective |
| chemotherapeutic agent | termed by Paul Ehrlich, any chemical substance used in medical practice |
| antibiotic agent | produced by microorganisms, inhibits the growth or destroys bacteria |
| synthetic drug | synthesized in a laboratory |
| semisynthetic drug | partly synthesized in a laboratory and partly produced by microorganisms |
| 1st gen cephalosporins | cefazolin, cephalexin; Gram + only |
| 2nd gen cephalosporins | cefoxitin, cefuroxime; more potent than 1st gen, better against Gram - |
| 3rd gen cephalosporins | cefotaxime, ceftriaxone; highly effective against Gram -, but reduced potency for Gram + |
| 4th gen cephalosporins | cefepime, cefpirome; enhanced activity against both Gram + and - |
| cephalosporin resistance | B-lactamase |
| vancomycin | inhibits peptidoglycan synthesis but cannot cross outer membrane (so only effective in Gram +) |
| polymyxins | interact with phospholipids, so disrupt cell membrane |
| amphoteracin B | interacts with sterols in cell membrane of fungi |
| polyenes | antifungal, ex. ketoconazole, spectazole |
| protein synthesis inhibitors - inhibit initiation (30s subunit) | aminoglycoside, TCN, spectinomycin |
| protein synthesis inhibitors - inhibit initiation (50s subunit) | chloramphenicol, macrolides |
| protein synthesis inhibitors - inhibitors of elongation | fusidic acid |
| aminoglycosides | protein synthesis inhibitor; binds to 30s ribosomal subunit; broad sprectrum (gentamicin, tobramycin, neomycin); renal toxic |
| tetracycline (TCN) | broad spectrum, low cost, used for acne/STDs, GI upset |
| chloramphenicol | broad spectrum; aplastic anemia, bone marrow suppression, leukemia, Gray baby syndrome |
| sulfonamides | used in combination with trimethoprim, pneumonia in AIDS patients/traveler's diarrhea, inhibits folic acid synthesis, which leads to no amino acids |
| quinolones | ciprofloxacin/levofloxacin/gatifloxacin/moxifloxacin, inhibits DNA synthesis (no unwinding of DNA) |
| chloramphenicol toxicity | aplastic anemia |
| ethambutol toxicity | visual disturbances |
| isoniazid toxicity | jaundice |
| metronidazole toxicity | antabuse effect in combination with alcohol |
| rifampin toxicity | liver dysfunction, red-orange saliva/sweat/urine |
| vancomycin toxicity | flushing (red man syndrome) |
| antimicrobial resistance | increase in MIC, relative of complete lack of effect of antimicrobial against a previously susceptible microbe |
| true pathogen | an organism that can cause disease in a healthy individual with an intact immune system |
| opportunistic pathogen | an organism that causes disease in an immuno-compromised host and grows in parts of the body that are not native to them |
| virulence | ability to establish itself in the host and cause damage |
| virulence factors | characteristics or structure that increase virulence, like exoenzymes, toxins and capsule |
| exoenzymes | degrade host tissue for nutrition, allows access to deeper tissues (ex. mucinase, keratinase, collagenase, hyaluronidase) |
| mucinase | digests mucus (nose, digestive tract) |
| keratinase | digests keratin (hair, nails) |
| collagenase | digests collagen (connective tissue) |
| hyaluronidase | digests the substance that cements the cells together (ground substance) |
| exotoxins | Gram + and -, highly toxic in small amounts, released when bacteria are still viable |
| endotoxins | Gram -, cell membrane (lipopolysaccharide), fever, released after cell has lysed |
| 1st phase of infection | incubation period |
| 2nd phase of infection | prodromal stage |
| 3rd phase of infection | period of invasion |
| 4th phase of infection | convalescent period |
| incubation period | time from initial contact with infectious agent to the appearance of the first symptoms; bacteria are multiplying but damage is insignificant. Can last several hours or several years (HIV) |
| prodromal stage | vague feelings of discomfort; nonspecific complaints |
| period of invasion | infectious agent multiplies at high level and becomes well established; more specific signs and symptoms |
| convalescent period | as the person begins to respond to infection, symptoms decline |
| localized infection | confined to a specific tissue |
| systemic infection | spread to several sites and tissue fluids, usually in the bloodstream |
| focal infection | infection breaks loose from local infection and is carried to other tissues |
| mixed infection | caused by several microbes (polymicrobial) |
| primary infection | initial infection |
| secondary infection | another infection by a different microbe |
| acute infection | comes on rapidly with severe but short-lived effects |
| chronic infection | progresses and persists over a long period of time |
| signs | objective (ex. fever) |
| symptoms | subjective (ex. I feel achy) |
| syndrome | several signs and symptoms pointing to a specific disease |
| asymptomatic (subclinical) | although infected, there is no sign of infection (ex. HIV) |
| chronic carrier | person with a latent infection who sheds the infectious agent |
| sequelae | long-term damage to tissues/organs |
| prevalence | TOTAL number of cases of disease in a population in a given time |
| incidence | the number of NEW CASES in a population |
| endemic | disease prevalence in a particular geographical area/region |
| epidemic | WIDESPREAD disease in a population EXCEEDS EXPECTED value in a given time period |
| pandemic | epidemic that affects a large proportion of the population over a widespread geographical area |
| mortality rate | total number of DEATHS in a population due to a certain disease |
| morbidity rate | number of people AFFLICTED with a certain disease |
| reservoir | primary habitat of pathogens in the natural world (human or animal carrier, soil, plants, water) |
| source | individual or object from which an infection is acquired |
| carrier | individual who inconspicuously shelters a pathogen and spreads it to others. may or may not have experienced disease due to the microbe |
Combine with other sets
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