Unit 6 & 7 Zoom Flashcards
Structurally, what do penicillin and cephalosporin have in common?
Do these two antibiotics target the same cell structure?
Beta lactam ring
Yes, it targets the CW in a similar way
(Affects only the structure that’s supposed to be made when the cell divides)
What does Endotoxin lipid A cause?
- Fever
- Shock
- Malaise/lethargy
- Blood pressure drop
- Blood coagulation
What phase of bacterial growth would you think antibiotics, like B-lactams, will be most effective? Why?
What other classes of drugs would also be most effective at the phase of bacterial growth?
Log phase; because these antibiotics prevent new CW to be made; it doesn’t affect already present CW
Those that affect protein and nucleic acid synthesis as well as metabolism would also be effective
What microbe is susceptible to INH and ethambutol?
What does INH do in this microbe?
(Usually given together)
Used against mycobacterium
INH looks like niacin (vitamin B6) so it can’t make NADH, interferes w/ mycolic acid synthesis
Why can’t you use old medication?
With age it becomes less effective
Not full dosage because there’s less
Why shouldn’t you use tetracycline while pregnant?
It binds calcium;
The baby needs calcium for bone and teeth growth
What is an analog?
A molecule that looks similar to another molecule so it should work similarly;
An analog of tetracycline can target protein synthesis and prevent codon recognition
Why do they use a cocktail for HIV?
So it can target multiple sites;
It is less likely for HIV to be resistant to every drug at each site
How might inhibition of tubulin from drugs effect mitosis and flagella?
No microtubule formation -> no cell division
Microtubules are responsible for moving the chromosomes to each side for cell division
No tubulin -> no movement for flagella
How does antibiotic resistance occur?
Antibiotics kill non resistant bacteria but leaves resistant bacteria and that bacteria is able to pass the gene and turn every other bacteria and make them resistant
By what methods can a bacterium acquire antibiotic resistance?
New mutations of chromosomal genes
Acquisition of R plasmids via transformation and conjugation
What does B-lactam target?
The cell wall
What are 4 mechanisms of resistance?
- An enzyme to destroy or inactivate the antibiotic
- Prevent/slow transport of the drug into the cell or pump it out faster than it can work
- Change the drug’s target or change metabolism slightly
- Biofilms can act to protect its community of microbes from antibiotics
What are the 5 stages of infectious disease in order?
- Incubation
- Prodromal
- Illness
- Decline
- Convalescence
Describe the 5 stages of infectious disease
1. Incubation: between the time when you were exposed and the mechanism of disease (no signs or symptoms)
2. Prodromal: when the infectious agent starts multiplying and induces an immune response (innate)
3. Illness: start getting more localized or systemic signs and symptoms of a particular disease (cough, fever, rash, etc.)
4. Decline: when the pathogen number is lowered or reduced in the body and reduction of signs and symptoms (secondary infection may arise cause of weak immune system)
5. Convalescence: body functions are going back to normal (no signs and symptoms, body starts to repair itself)
What are Koch’s postulates?
- Suspected causative agent must be found in every case of the disease and be absent from healthy hosts
- Agent must be isolated and grown outside the host
- When agent is introduced into a healthy, susceptible, host, the host must get the disease
- Same agent must be found in the diseased experimental host
What are limitations of Koch’s postulates?
- Can’t be cultured
- Some diseased cause by a combination of variables (pathogens, environmental, genetics)
- Ethical issues: human only diseases -> can’t infect healthy humans
- Signs/symptoms of infection may occur in different diseases (other)
- Some agents are ignored
Covid:
- Possible modes of transmission
- Signs and Symptoms
- Pandemic, epidemic, endemic?
- Mortality rate thus far
- Zoonotic? Original host?
- Causative Agent
- Vaccines? Preventions?
- Respiratory, droplet transmission, direct contact
- Fever, cough, trouble breathing, headache, sore throat, nausea, muscle aches, fatigue, loss of taste or smell
- Pandemic
- As of June 1, 2024, 1.2 million people in the US have died from covid since the beginning of it
Rate: 302.9 deaths over 1000,000 people - Yes, Zoonotic (maybe bats)
- Sars coV2 virus
- J&J, pfizer, moderna
use ppe, disinfecting, social distance, quarantining
To take care of food and water?
Chlorinated water to wash fruits and veggies
UV light
Cook meat properly and at right temperatures
Prevent cross contamination on cutting boards
To clean water?
Use clean cloth to take out any large debris
Boil water
No heat:
filter water of debris
add about 8 drops of unscented 6% bleach
let sit for 30 mins
What 3 major factors contribute to HAI?
- Exposure to numerous pathogens in hospitals
- Weakened immune systems of ill patients
- Transmission of pathogens among patients & healthcare providers
What line of defense?
Dendritic cell
TLR
Second
Word association
Histamine
Diapedesis
Interferon
Lectin
TLR
Opsonization
Dendritic cell
Histamine: inflammation
Diapedesis: movement
Interferon: chemical defense against viruses
Lectin: complement pathway
TLR: phagocytosis
Opsonization: phagocytes
Dendritic cell: innate system signal to adaptive immune response/cells what they need to look for
First line of defense
Mechanical:
(barrier against microorganisms)
Skin, gut, lungs, eyes/nose/oral
Epithelium/mucus membranes
First line of defense
Mechanical: 2nd row
(barrier against microorganisms)
Skin & Gut
Air flow or fluid
Lungs
Mucociliary escalator
**Eyes/Nose/Oral
Tears, nasal cilia
First line of defense
Chemical
Skin
Fatty acids, defensins, cathelicidins
Gut
Low pH, enzymes (pepsin), defensins, cathelicidins
Lungs
Pulmonary surfactants (lipids and proteins) lining surface or alveolar surface, defensins, cathelicidins
*Eyes/Nose/Oral**
Lysozyme in tears and saliva, defensins, histatins
First line of defense
Microbiota
Skin, gut, lungs, eyes/nose/oral
Normal microbiota
