Dr Rahul Kunkulol's Power point Presentations

1. DR.RAHUL

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“Treatment of systemic infections with
specific drugs that selectively suppress
the infecting microorganism without
affecting the host”.

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• Treatment of neoplastic diseases with
drugs is also called as Chemotherapy
• This is due to analogy between the
pathogenic organism and malignant cells

4. :
Naturally occurring substance produced
by the microorganism, that inhibits or
kills other microorganism at very low
concentration
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5. :
Natural, semi-synthetic or synthetic
substance that inhibits the growth or kills
bacteria
Natural, semi-synthetic or synthetic
substance that inhibits the growth or kills
microorganisms.
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6. • Medications used to treat bacterial
infections
• Ideally, before beginning antibiotic
therapy, the suspected areas of infection
should be cultured to identify the
causative organism and potential antibiotic
susceptibilities.
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7. Treatment of an
infection before specific culture
information has been reported or
obtained
Treatment with
antibiotics to prevent an infection, as in
intra-abdominal surgery
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8. • Chemical structure
• Type of action
• Spectrum of activity
• Type of organism against which primarily
active
• Source of antibiotics
• Mechanism of action
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• Sulfonamides
• Tetracycline
• Macrolides
• Aminoglycosides

10. Kill bacteria
Inhibit growth of
susceptible bacteria, rather than killing
them immediately; will eventually lead to
bacterial death
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11. • Antibiotics inhibit
a narrow range of
bacteria
• Preferable when
organism has been
identified
• Antibiotics inhibit
a wide range of
bacteria
• Indicated if
infecting organism
not yet identified
Broad spectrum Narrow spectrum
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14. Antimicrobial agents inhibit 5 essential
bacterial processes
1. Protein synthesis
2. Folic acid synthesis
3. DNA synthesis
4. RNA synthesis
5. Cell wall synthesis
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15. • Ribosome is a protein factory in bacteria takes mRNA in and
produces proteins from them.
• Bacterial ribosome has 2 parts:
• 30S binds to mRNA to translate mRNA into amino acids, which
form proteins
• 50S required for peptide elongation
• 3 phases from mRNA to protein
• Initiation
• Elongation
• Termination
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16. • Macrolides
• Aminoglycosides
• Tetracyclines
• Chloramphenicol
• Oxazolidinones
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17. Dihydropterate
Dihydrofolate
Tetrahydrofolate
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18. • Enzymes required for DNA replication
• Topoisomerase II (DNA gyrase): GyrA and GyrB
• Topoisomerase IV: ParC and ParE
• Quinolones interact/bind to the
topoisomerases, which stops DNA
replication e.g. Nalidixic Acid, Ciprofloxacin
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19. • Forms a stable complex with bacterial
DNA-dependent RNA polymerase
• Prevents chain initiation process of DNA
transcription
• Mammalian RNA synthesis not affected
as RNA polymerase is much less sensitive
to Rifampicin
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22. • Exposure to sub-optimal levels of
antimicrobial
• Exposure to microbes carrying resistance
genes

23. • Prescription not taken correctly
• Antibiotics for viral infections
• Antibiotics sold without medical
supervision
• Spread of resistant microbes in hospitals
due to lack of hygiene

24. • Lack of quality control in manufacture or
outdated antimicrobial
• Poverty or war
• Use of antibiotics in foods

25. • Antibiotics are used in animal feeds and
sprayed on plants to prevent infection and
promote growth
• Multi drug-resistant Salmonella typhi has
been found in 4 states in 18 people who
ate beef fed antibiotics

26. • Infections resistant
to available
antibiotics
• Increased cost of
treatment

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