Antibiotics, Cancer And Antivirals Random facts Flashcards
Bacterostatic + bacterostatic
No synergy
Sometimes additive
Bacterocidal + bacterocidal
Sometimes synergistic
Almost always additive
Bacterocidal + bacterostatic
Bacterostatic drug inhibits bacterocidal drug
Not inhibited by bacterostatic drug
Polymixin
MOA does not depend on organism replicating
Conjugation
Bacteria sex
Transduction
Pickup DNA from virus
Transformation
Picks up DNA from environment
Ph that I activates penicillins
<6
Acid stable penicillins
Phenoxymethyl penicillin
Dicloxacillin, oxacillin, cloxacillin
Amoxacillin
Not sensitive to Penicillinase
Methicillin
Dicloxacillin, oxacillin, cloxacillin
Nafcillin
Broad spectrum penicillins
Ticaricillom Amoxacillin Piperacillin Carbenicillin Azlocillin
Antibiotics effective against anaerobes
Piperacillin
Clindamycin
Imipenem
3rd gen cephalosporins
First gen cephalosporins
Cephalexin (oral)
Cephazolin (Im)
Similar to broad spectrum penicillins
Not effective against anaerobes
2nd gen cephalosporins
Cefaclor
More effective against gram -
3rd gen cephalosporins
Cefotaxime Cefixime Less effective against gram (+) More effective against gram - and anaerobes Distributes to CNS
4th gen cephalosporins
Cefepime
Function of 14-alpha-sterol demethylase
Lanosterol to ergosterol
Blocked by anole anti fungal drugs
Function of squalene epoxidase
Squalene to lanosterol
Blocked by allylamine anti fungal drugs
Terbinafine
Enhances NMJ blocking drugs
Aminoglycosides
Oral tetracycline
Minocycline
Preferred during pregnancy tetracycline
Oxytetracycline
Chloramphenicol associated bone marrow suppression
Marrow: normlcellular Blood: anemia Dose response: dose related Time of appearance: during treatment Symptoms: anemia Prognosis: recovery
Chloramphenicol associated aplastic anemia
Marrow: hypo plastic, aplastic Blood: pancytopenia Dose response: not dose related Time of appearance: days/months later Symptoms: purpura and or hemorrhage Prognosis: often fatal
First new topical antibiotics approved in 20 years by the FDA
Retamulin-pleuromutilin derivative
Sulfonamide with highest basic and acidic solubility
Sulfisoxazole
Action of dihydrofolate reductase
Reduce dihydrofolate to tetrahydrofolate
Blocked by trimethoprim
Action of dihydrodynthetase
PABA to folate
Blocked by sulfonamides
Action of thymidate synthase
dUMP to dTMP Blocked by flucytosine Uptake by cytosine permeases Delaminated to 5-FU by cytosine deaminase Both only found in mammal cells
Oncogenes
Drive cell proliferation
Normal homologos are termed protooncogenes
Tumor suppressor genes
Prevent cell proliferation
Mutated, silenced or missing in cancer cells
7 hallmarks of cancer
An inflammatory environment Insensitivity to growth inhibitors Self sufficiency in growth signals Limitless replicative potential Sustained angiogenesis Evasion of apoptosis Tissue invasion and metastasis
Cell cycle
G1 phase: synthesis of cellular components needed for DNA synthesis
S phase: DNA synthesis
G2 phase: synthesis of cellular components for mitosis
Mitosis: cell division
G0: prolonged G1 phase neurons and hepatocytes
18-24 hours for rapidly proliferating
Growth fraction
Percent of cells traversing cell cycle
Cycle active drugs
Affect particular point in cell cycle
High growth fraction more sensitive to cycle active drugs
Non cycle active drugs
Affect any part of cell cycle
Low or high growth fractions
Cell kill hypothesis
Kill virtually all cells to have effective treatment.
Use multiple drugs each kills a characteristic percent of target cells
High doses-synergistic
Metabolomics
Analysis of metabolite profiling
E.g sarcosine is a measure of prostate Tumor aggressiveness
More sarcosine= more malignancy
Don’t use which two drugs together since they have similar receptors and there actions can cancel
Macrolides and chrloramphenicol
