Exam 3 Chapter 11-15 Flashcards
What are the three major factors that contributed to the decline in deceases in the 20th century?
1- Improved water and sanitation treatment
2- vaccines
3- Antimicrobial drugs and antibiotics
What is the goal of Antimicrobial Therapy?
To destroy the disease-causing organisms without harming the host cell
Antibiotic
A natural product made by one microbe that inhibits or destroys another microbe
Antimicrobial drug
Made in the laboratory
Synthetic products made in the lab
Semi-Synthetic drug
Product made by the bacteria or mold, and is chemically altered to increase the effectiveness
The goal of Antimicrobial drugs
Cellular microbe: the goal is to disrupt the cell structure or process
A virus: Antimicrobial drugs works by stopping viral replication.
Why must Antimicrobial drugs be selective toxic?
Must be able to specifically inhibit or destroy the microbe or virus, NOT the host cell
What does it mean when a drug has a spectrum of activity?
A group of organisms that is it useful to treat.
A narrow spectrum antibiotic or drug
A limited group it can treat. Or targets a specific group
A broad spectrum of antibiotics or drug
Treats a wider group. Or more than one groups
Bacteriostatic or Bacteriocidal
Static: slows down the growth of bacteria
Cidal: destroys the bacteria
Depends on the organism, agent or concentration
Administration of drug intake:
- Topically(on the skin)
- Orally(pills or liquid medicine)
- Injection
- IV
The largest spectrum of antibiotics are?
Tetracycline
Who discoverer penicillin?
Alexander Fleming in 1928
Result: Many diseases that were once huge problems are rare today.
How can antibiotics work?
- Inhibits cell wall synthesis
- Inhibits protein synthesis
- Inhibits of nucleic acids
- Disruption of cell membrane( cells becomes leaky)
- Inhibition of a key metabolic pathway(eg. folic acid synthesis)
Inhibiting of cell wall synthesis
Penicillin.
- naturally occurring
- semi-synthetic penicillin. benefits: increased spectrum of activity (group of organisms it is used to treat) & is more resistant to penicillinase.
Cell Wall inhibitors
Block synthesis and repair:
Penicillin
Cephalosporin
Carbapenems
Vancomycin
Bacitracin
Fosfomycin
Isoniazid
Inhibiting of protein synthesis
Causes loss of selective permeability
-Polymyxins
-Deptomycin
Inhibiting of nucleic acids. DNA/RNA
-Inhibits replication and transcription
-Inhibits gyrase (unwinding enzyme): Quinolone
-Inhibits RNA polymers: Rifampin
Inhibition of cell wall: Bacitracin
Inhibits the lipid carrier involved in transporting across cell membrane to build the cell wall structure
Inhibition of cell wall: Vancomycin
Stops the elongation of peptidoglycan
Inhibition of cell wall: Isoniazid and Ethambutol
