chapter 12 and 13 (week 5) learning objectives

What are antibiotics

are substances produced by the natural metabolic processes of some microorganisms that can inhibit or destroy other microorganisms

What are synthetic drugs

Are synthesized entirely in the lab through chemical reactions

What are semisynthetic antimicrobial drugs

Chemically modified in the laboratory after being isolated from natural sources

What is the spectrum of a antimicrobial drug

range of activity of a drug

What is the narrow spectrum of antimicrobial drugs

drugs– effective on a small range of microbes They Target a specific cell component found only in certain microbes

What is the broad spectrum of antimicrobial drugs

drugs– greatest range of activity TheyTarget cell components common to most pathogens

What do penicillins do to the cell wall

Interrupt the completion of the cell wall

Are penicillins narrow or broad spectrum

can be narrow-spectrum or broad-spectrum, which depends on how far they penetrate

What acts against gram positive and negative bacteria

Amoxixillan

Cephalosporin antibiotics are __

Similar to penicillins in structure and mode of action, Versatile, and causes fewer allergic reactions

What is drug resistance

is an adaptive response in which microorganisms begin to tolerate an amount of drug that would ordinarily be inhibitory

How does drug resistance developed

1. Spontaneous mutations in critical chromosomal genes

2. Acquisition of new genes or sets of genes via transfer from another species

What are exogenous agents

Agents that originate from source outside the body

What are endogenous agents

Agents that already exist on or in the body (normal flora)

What are the steps of infection

1. entry through the portal of entry

2. adhesion

3. evasion of host defenses

What are the stages of clinical infection

1. Incubation

2. Prodromal stage

3. Period if invasion

4. Convalescent period

               

What occurs in the incubation period

time from initial contact with the infectious agent to the appearance of first symptoms

What occurs in the prodromal stage

vague feelings of discomfort; head and muscle aches, fatigue, upset stomach, malaise

What happens during the period of invasion

multiplies at high levels, becomes well-established; more specific signs and symptoms

What occurs in the convalescent period

as person begins to respond to the infection, symptoms decline

What is a localized infection

Microbes enter the body and remain confined to a specific tissue

What is a systemic infection

infection spreads to several sites and tissue fluids usually in the bloodstream

What is a mixed infection

several microbes grow simultaneously at the infection site - polymicrobial

What is an acute infection

comes on rapidly, severe but short-lived effects

What is a chronic infection

progress and persist over long period of time

What are the signs of inflammation

Edema

Granulomas and abscesses

Lymph nodes

What is edema

Accumulation of fluid

What are granulomas and abscesses

Walled off collections of inflammatory cells and microbes

What is lymphadenitis

Swollen lymph nodes