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1
Q

Chemicals that affect physiology in any manner are

A

Drugs

2
Q

drugs that act against disease

A

Chemotherapeutic gene

3
Q

impairs normal function of tissue or organ.

A

Disease

4
Q

Drugs that treat infections

A

Antimicrobial agents

5
Q

infective agent, establishes residence in a host

A

Infection

6
Q

“Magic bullets” chemicals killed microbes

A

Paul Ehrlich

7
Q

Discovered sulfanilamide 1st antimicrobial agent which effective against a wide variety of microbe infections

A

Gerhard Domagk

8
Q

Other organisms (streptomyces) produce antimicrobial agents .. coined the term antibiotics

A

Selman waksman

9
Q

Chemically altered antibiotics that are more effective than naturallly occuring ones

A

Semi-syntheetics

10
Q

antimicrobials that are completely synthesized in a lab

A

synthetics

11
Q

(is fundamental) toxic to pathogen, not host

A

Selective toxicity

12
Q

Because prokaryotic bacteria are signigicantly different in structure, composition, and metabolism, antibacterial drugs constitute largest number and diversity of

A

antimicrobial agents

13
Q

Fewer drugs to treat eukaryotic infections, and viruses

A
  • Eukaryotic pathogens are more similar to humans

- Viruses are intracellular parasites of humans

14
Q

Prevent bacteria from increasing amount of peptidoglycan, having no effect on existing peptidoglycan layer
Effective only for growing cells

A

Inhibition of bacterial wall synthesis

15
Q

Most common agents, prevent cross-linkage of NAM subunits

A

Beta-lactams (most prominent) in preventing cross-linkage of NAM

16
Q

Functional group which bind to enzymes that cross-link NAM subunits results in weakend bacterial cell wall and lysis

A

Beta-Lactams

17
Q

Examples of Beta-lactams

A

Penicillans and cephalosporins

18
Q

Beta lactams rings are the functional portion of the ______________.

A

Beta-lactum anti-microbials

19
Q

Inhibition of synthesis of bacterial walls

A
  • Semi-synthetic derivatives of beta-lactams
  • more stable in acidic environment
  • more readily absorbed
  • less susceptible to deactivation
  • more active against more tupes of bacteria
20
Q

Inhibiation of synthesis of bacterial walls

Interfere with particular brdge that link NAM subunits in many gram-postive

A

Vancomycin and Cycloserine

21
Q

Inhibiation of synthesis of bacterial walls

blocks secretion og NAG and NAM from cytoplasm to cell wall

A

Bacitracin

22
Q

Inhibiation of synthesis of bacterial walls

Disrupt mycolic acid (tuberculosis) formation in mycobacterium

A

Isonlazid and ethambutol

23
Q

Inhibition of protein synthesis

Prokaryotic ribosoes

A

70s (30s and 50s)

24
Q

Inhibition of protein synthesis

Eukaryotic ribosomes

A

80s(60s and 40s)

25
Q

Inhibition of protein synthesis

Drugs can selectively target prokaryotic ribosomes, (without affecting Euk. ribsosomes) preventing translation … notranslation, no proteins…. death

A

eukaryotic

26
Q

Inhibition of protein synthesis

Mitochondria of animals and humans contain

A

70s ribosomes

27
Q

Inhibition of protein synthesis

Change shape of 30s subunit

A

Aminoglycosides

28
Q

Inhibition of protein sy

Example of Aminoglycosides

A

(steptomycin and gentamicin

29
Q

Inhibition of protein sy

Black A-site of ribosomes (block tRNA binding)

A

Tetracyclines

30
Q

Inhibition of protein sy

Block enzymatic site of 50s Subunits

A

Chloramphenicol

31
Q

Inhibition of protein synthesis

Bind to a portion of 50s, prevent movement to next codon (3)

A

Lincosamides
Streptogramins
Macrolldes

32
Q

Inhibition of protein synthesis

RNA and ssDANA which bind to complementary mRNA of pathogens

A

Antisense nucleic acids

33
Q

Inhibition of protein synthesis

Block formation of 50s and 30s subunits

A

Antisense nucleic acids

34
Q

Block iniiation of translation

A

Oxazolidinones

35
Q

Disruption of cytoplasmic membranes

Some drugs form channel through cytoplasmic membrane and

A

damage its integrity

36
Q

Disruption of cytoplasmic membranes

(antifungal drugs) form a channel in membrane, destroy integrity

A

Polyenes

37
Q

Disruption of cytoplasmic membranes

Examples of polyenes

A

Amphotericins B attaches to ergasterol in fungal membranes

38
Q

Disruption of cytoplasmic membranes

antifungal drugs) inhibit of synthesis of ergosterol (membrane isnt intact

A

Azole and Allylamines

39
Q

Fungal similar to choresterol

A

Ergosteral

40
Q

Disruption of cytoplasmic membrane by amphotericin B

(bacteria lack sterols), typically not affected polyenes (amphotericin B) interacts with

A

Ergosterol and form apore in fungi

41
Q

inhibition of Metabolic pathways

affect the metabolism of the pathogen and not the host

A

Antimetabolic agents

42
Q

inhibition of Metabolic pathways

Class of antimetabolic drugs, chemically similar to para-aminobenzoic acid (PABA)

A

Sulfonamides

43
Q

inhibition of Metabolic pathways

_______ outcompete for active sites of PABA, and eventually slow production of DNA and RNA,,,, cell death

A

Sulfonamides

44
Q

Inhibtion of Nucleic Acid Synthesis (3)

A
  • Several drugs block DNA replication or mRNA transcription
  • Drugs often affect both eukaryotic and prokaryotic cells
  • Not normally used to treat infections, used in research
45
Q

Inhibtion of Nucleic Acid Synthesis

Interfere with funcation of nucleic acids

A

Nucleotide analogs

46
Q

Inhibtion of Nucleic Acid Synthesis

nucleotide analogs

A

Distort shapes of nucleic acid molecules and prevent further replication, transcription, or translation

  • MOst ofter used a against viruses
  • effective against rapidly dividing cancer cells
47
Q

Sugar and nitrogenous base (missing a PO4^3-)

A

Nucleoside

48
Q

Inhibtion of Nucleic Acid Synthesis

Act against reverse transcriptase enzyme HIV uses in its replcation cycle

A

Reverse transcriptase inhinitors

49
Q

Inhibtion of Nucleic Acid Synthesis

Do not harm peope because humans lack reverse transcriptase

A

Reverse transcriptase inhibitors

50
Q

Inhibtion of Nucleic Acid Synthesis

Prevention of virus attachment

A

Attachment antagonists block viral attachment or receptor proteins so viral pathogen fails to enter host
-New area of antimicrobial development

51
Q

Clinical Cosiderations in prescribing Antimicrobial drugs

Ideal antimicrobial agents

A
  • Readily available
  • enexpensive
  • Chemically stable
  • Easily administered
  • Nontoxic and nonallergenic
  • Selectively toxic against wide range of pathogens
52
Q

number of different pathogens a drug acts against

A

Spectrum of action

53
Q

__________effective against few organisms

A

Narow -spectrum drugs

54
Q

_______________effective against many organisms

A

Broad-spectrum drug

55
Q

May allow for secondary or superinfections to develop because normal microbiota may be killed reducing microbial antoganism

A

Broad-spectrum

56
Q

Specific classes of drugs are used for specific pathogens, some drug can target

A

Multiple pathogens

57
Q

Efficacy is ascertained by

__________: disks of antibiotics are placed on agar with microbial lawn, zone of inhibition is measured

A

Diffesion susceptibility test

58
Q

Efficacy is ascertained by
_____________: broth dilution test of antimicrobials, determines smallest (drug) to inhibit microbe growth and reproduction

A

Minimum nhibitory concentration test

59
Q

Efficacy is ascertained by

___________: broth dilution test of antimicrobials, determines smallest (drug) to kill microbe

A

Minimum bactericidal concentration test

60
Q

Routes of adminstration

______________ of drug for external infections

A

Topical application

61
Q

Efficacy is ascertained by

_________ requires no needels and is self administered

A

Oral route

62
Q

Efficacy is ascertained by

___________ delivers drug via needl into muscle

A

Intramuscular administration

63
Q

Efficacy is ascertained by

____________ delivers drug directly to bloodstream

A

Intravenous adminstration

64
Q

Must know how antimicrobial agent will be distributed to infected tissue

A

Efficacy is ascertained by

65
Q

Safety and Side Effects

Toxicity

A
  • Cause of many toxic reactions poorly understood
  • Drugd may be toxic to kidneys, liver, or nerves
  • Consideration needed when prescribing druug to pregnant woment (drugs pass from placenta to fetus)
66
Q

Safety and Side Effects

Allergies

A

Allergic reactions are rare but may be life threatening

67
Q

Life threatening allergic reactions

A

Anaphylactic shock

68
Q

The development of resistance in populations

A

some pathogens are naturally resistant

69
Q

Resistance by bacteria acqured in 2 ways

A

Mutations of gene may result in resistance

Acquisition of R-plasmid via transformation, transduction, and conjugation

70
Q

Mechanisms of microbial resistance (6)

A

1) producation of enzymes that destroys or deactivates drug
2) slow or prevent entry of drug intio the cell
3) Alter target of drug so it binds less effectively
4) alter their metabolic chemistry
5) pump antimicrobial drugs out of the cell before it can act
6) producation of protien which prevents binding of drigs

71
Q

How B-lactams renderspenicillin inactive

A

B-lactams (penicillinase) breaks covalent bond in lactam ring of penicillin, redering it inactive

72
Q

Multiple resistance and cross resistance

A

Pathogen can acquire resistance to more than one drug

  • Common when R-plamids exchange
  • Develop in hospitals and nursing homes
  • -Constant use of drugs eliminates sensitive cells, resistant strains more prominent
73
Q

Maintain high (drug) in patient for sufficient time; kill all sensitive cells and inhibit other so immune system can destroy

A

Retarding resistance

74
Q

Use antimicrobials only when necessary

  • develop new vaiaionts of exsiting drugs
  • Search for new antibiotics, semi- synthetics, and synthetic
A

retarding resistance

75
Q

Use antimicrobial agents in combination of

A

Synergism

76
Q

1 drug enchances effectiveness of another drug

A

Synergism