Block 1

Question 1

chemotherapeutic agents

Answer 1

non-toxic compounds used internally to treat infection e.g. antibiotics

Question 2

disinfectants

Answer 2

are toxic chemicals that kill microorganisms and are used for treatment of non-living objects e.g. formaldehyde and chlorine

Question 3

Antiseptics

Answer 3

are chemical substances that kill microorganisms/inhibit their growth and are applied to living tissues e.g. 60%-85% ethanol in sanitisers

Question 4

difference between antimicrobials vs antibiotics

Answer 4

antimicrobals are natural or synthetic compunds that kill microorganisms or inhibit their growth whereas antibiotics are chemical compunds produced by microorganisms to inhibit or kill other microorganisms (penicilin)

Question 5

bacteriostatic

Answer 5

substance or treatment that inhibits the growth and reproduction of bacteria without necessarily killing them. used in food production to preserve long-life of foods
-relies on the bodys immune system to remove remove the bacteria

Question 6

bacteriolytic

Answer 6

bacteriolytic agents cause the bacterial cell wall or membrane to rupture, resulting in the complete disintegration of the cell.
-so kills bacteria and removes them from the body
-sometimes can induce the immune system inducing shock due to too much lipopolyscarrides (LPS)

Question 7

bactericidal

Answer 7

directly kills bacteria, as opposed to merely inhibiting their growth.

Question 8

The minimum inhibitory concentration (MIC)

Answer 8

the lowest concentration of the antimicrobial agent that results in inhibition of visible growth of the test organism under standard conditions

Question 9

the minimum bactericidal/ concentration

Answer 9

the minimum bactericidal concentration (MBC) is the lowest concentration of the antimicrobial agent that kills 99.9% of the original inoculum in a given time

Question 10

methods for determining antimicrobial sensitivity

Answer 10

-epsilometer test
micro-dilution test
-measurements of inhibition zones-disc-assay
-kirby-bauer method
-PCR

Question 11

classification of antimicrobals

Answer 11

-based on their structure
-e.g. aminoglycosides,macrolides,tetracyclines
-or can be based of what they target e.g. celll wall synthesis inhibitors=penicillin

Question 12

Narrow-spectrum

Answer 12

antimicrobals are active against a single group of microbes e.g. vanocomycin

Question 13

broad spectrum

Answer 13

antimicrobals act both on gram-positive and gram negative bacteria e.g. quinlones

Question 14

extended spectrum antimicrobals

Answer 14

semi-synthetic antibiotics with wider spectra of activity and resiistant to action of extended-spectrum beta-lacamases (e.g. carbapenems)

Question 15

enhanced spectrum antimicrobals

Answer 15

improved activity against Gram-positive bacteria and anaerobes

Question 16

treatment of fungal infections

Answer 16

-polyenes= interfere with the assembly of the fungal cell wall by inhibiting synthesis of ergosterol
-azoles= targetss ergosterol
-flucytosine=acts as pyrimidine inhibitors and distrpts DNA and protein synthesis in fungi

Question 17

advantage of multiple drug therapy

Answer 17

-it prevents the development of drug resistance
-it is more effective
-it suits for the long-term treatment e.g. in the case of tuberculosis

Question 18

addiditivity

Answer 18

-two drugs do not interact, and their combined outcome is the sum of two individual outcomes

Question 19

synergism

Answer 19

the combined effect of two drugs is greater than the sum of two indivuial outcomes

Question 20

antagonism

Answer 20

the combined effect is less than the addictive effect e.g. one antimicrobal prevents the full effect of other

Question 21

alternative treatments

Answer 21

-phage treatments
-probiotics
-gene therapy

Question 23

antibiotic resistance

Answer 23

-when bacteria,viruses,fungi and parasites change over time and no longer respond to medicines making infections harder to treat and increasing the risk of disease spread,severe illness and death

Question 24

causes of antimicrobal resiatance

Answer 24

-over-prescribing of antibiotics
-pateints not finsihing their treatments
-overuse of antibiotics in livestocks and fish farming
-lack of hygiene and poor sanitation
-lack of new antibiotics being developed

Question 25

population resistomes

Answer 25

the collection of all the genetic elements in a group of microorganisms that give them the ability to resist antibiotics and other antimicrobial agents.

Question 26

innate antimicrobal resistance

Answer 26

the inherent ability of certain microorgaism to resist the effects of antimicrobals agents, -part of the biological mechanism e.g. drug targets are absent -lack of specific metabolic pathways

Question 27

how do microbes acquire antimicrobial resistance

Answer 27

-mutations -DNA transfer via: -Plasmids -phages -transponses -Genomic islands

Question 28

drug inactivation

Answer 28

process where bacteria (or other organisms) destroy or modify a drug, so the drug can no longer kill or stop them from growing. This can happen because bacteria produce enzymes that break down the drug or change its structure, rendering it ineffective. -e.g. B-lacatamases which break down the B-lactam rings making the antibiotics ineffcetive -

Question 29

modification of target

Answer 29

- bacteria change the structure of the specific molecules (targets) that a drug is supposed to bind to and attack. If the target is altered, the drug can no longer bind to it effectively, and thus, it can’t harm the bacteria. e.g. seen in TB drugs