Keywords: 30-40 Flashcards
30 Examples of antigenic or phase variation (6)
Plasmodium falciparum (malaria)
Borrelia burgdorferi (Lyme disease)
Neisseria meninigitidis (meningitis)
Salmonella (flagellar phase variation, food borne illness)
Haemophilus influenzae (respiratory infection)
Helicobacter pylori (gastric ulcers)
30 Microbes that escape the phagosome to live in the cytoplasm (4)
Listeria monocytogenes
Trypanasoma cruzi
Shigella
Rickettsia
32 Toxins:
Definition
Types of organisms that make toxins
Two types
Bacterial exotoxins
- Type
- Amount relative to endotoxin
- Bacterial cell toxin production
- Better toxin producers: gram+/-
- Good for…
Types
- Mycotoxin
- Neurotoxin
- Enterotoxin
- Hemolysin
biological molecules that can kill in small quantities
bacteria & some fungi & parasites
- Endotoxin: part of LPS or LOS, heat-stable
- Exotoxin: heat-labile
- proteins
- active in smaller amounts than endotoxin
- one bacterial cell can make >1 toxin
- gram+ bacteria are better toxin producers
- vaccine targets
- fungal
- nervous system
- GI system
- lyses RBCs
32 Drugs Against
Drugs with some activity against Pseudomonas
Resistance
For P-Ts, Carb not Erta & FQ not Moxi TACC PA
Piperacillin/tazobactam Carbapenems (not Erta) Fluoroquinolones (not Moxi) Ticarcillin-clavulanate Aztreonam Cefepime Ceftazidime Polymyxins Aminoglycosides
Quinolones, aztreonam, & others
32 Comparision of T-cell Stimulation by Conventional Antigens vs. Superantigens:
Conventional antigen
- T cell response
- Cytokine release
- Next
- Result
Superantigen
- T cell response
- Cytokine release
- Next
- Result
- small subset of T cells respond
- desirable release of cytokines like IL-2
- T cell : B cell interactions
- antibody formation
- massive T cell response
- excess release of IL-2, etc.
- strong release of TNF & other proinflammatory cytokines
- shock, fever
35 Most common health problems in travelers (4)
Main cause of morbidity
- diarrhea
- respiratory infections
- skin disorders
- febrile illnesses
accidents
35 Causes of the symptoms of infection in returned travelers:
1) Eco-challenge in Borneo
2) Swimming in Lake Malawi
3) Unprotected MSM in Amsterdam
4) Beach vacation in Bermuda
5) Camping in rural Cambodia
6) Exploring food from street vendors in Bangkok
7) Spelunking in Mexico
1) leptospirosis
2) schistosomiasis
3) HIV, Lymphogranuloma venereum, HSV, syphilis
4) cutaneous larva migrans
5) Japanese encephalitis
6) hepatitis A, E, typhoid fever
7) histoplasmosis
35 Duration:
Short exposure during travel increases the incidence of… (4)
Long exposure to the local environment or people increases the risk of… (2)
- influenza
- diarrhea,
- upper respiratory infections (URI’s)
- non-travel related illness
- tuberculosis
- parasitic diseases such as amebic liver abscess or strongyloidiasis
35 Causes of illness in returning travelers:
Most common (9)
Most urgent (4) - All cause...
– Malaria – Infected insect bite – Diarrhea – Upper respiratory illness (URI) – Dengue – Typhoid – Chikungunya – Hepatitis A – Rickettsial infection
– Malaria
– Typhoid
– Amebic liver abscess
– Viral Hemorrhagic Fever
Fever
35 Common etiologies in returning travelers:
Fever (5)
Diarrhea
- Bacterial (4)
- Protozoa (3)
- Viral (2)
Confusion (4)
Jaundice (4)
- Malaria
- Dengue Fever
- Typhoid fever
- Acute schistosomiasis (Katayama fever)
- Leptospirosis
- E. coli, Salmonella, Shigella, Vibrio cholerae
- Giardia, Cryptosporidium, Entameba
- Norovirus, Rotavirus
- Viral encephalitis (Japanese encephalitis, West Nile virus)
- Meningococcal meningitis
- Typhoid fever
- Malaria
- Hepatitis A
- Hepatitis B
- Hepatitis E
- Yellow fever
36 Antiretroviral Therapy of HIV-1:
Nucleoside analog reverse transcriptase inhibitors (NRTIs)
- Mechanism of action
- Examples (5)
- Some known adverse effects (3)
Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
- Mechanism of action
- Examples (2)
- Some known adverse effects (3)
Protease Inhibitors (PIs)
- Mechanism of action
- Examples (2)
- Some known adverse effects (1)
Fusion Inhibitors
- Mechanism of action
- Examples (1)
Integrase inhibitors/ Integrase Strand Transfer Inhibitors (INSTI)
- Mechanism of action
- Examples (1)
Entry inhibitors
- Mechanism of action
- Examples (1)
Combination ARTs
- Examples (1)
Nu
- Bogus substrate for RT, terminates DNA chain
- Zidovudine, Lamivudine, Emtricitabine, Abacavir, Tenofovir
- Bone marrow suppression (Zid), renal insufficiency (Ten), hypersensitivity reaction (Aba)
No
- Non-competitive inhibitor, freezes enzyme so it can’t catalyze polymerization
- Efavirenz, Nevirapine
- Dizziness, vivid dreams, rash
P
- Compete w/ normal substrate for binding protease, blocking its activity
- Ritonavir (pharmacologic booster), Atazanavir
- Mild hyperbilirubinemia
F
- Binds gp41 protein, blocks fusion of viral & host membrane, administered subcutaneously
- Enfuvirtide
I
- HIV integrase is essential for proviral DNA integration into host chromosomal DNA, well-tolerated
- Raltegravir
E
- Occupies the CCR5 HIV-1 co-receptor and blocks virus entry, not active against virus that can use the alternate CXCR4 HIV-1 co-receptor
- Maraviroc
C
- Atripla: Efavirenz, Tenofovir, & Emtricitabine
36 Antiretroviral Therapy of HIV-1:
Benefits of ART (5)
Antiretrovial Therapy
- Duration
- Recommended for… (5)
ART Drug Combinations
- Backbone
- Plus…
- Pregnant women
B
- Increases CD4+ T cell counts
- Delays progression
- Decrease risk for consequences of chronic immune activation
- Prolongs survival
- Decreases transmissibility
A
- Lifelong treatment, drug compliance necessary
- Symptomatic HIV/AIDS, CD4+ < 500, nephropathy, Hepatitis B, & pregnant women
A
- Dual NRTI backbone: Tenofovir + Emtricitabine
- Plus:
o An NNRTI: Efavirenz
o A Ritonavir-boosted protease inhibitor: Atazanavir or Darunavir
o An integrase inhibitor: Raltegravir
- For pregnant women: Efavirenz?
39 Pathogens that Establish a Persistent or Latent Infection:
Bacteria (2)
Protozoa (3)
Viral (10)
- Mycobacteria
- Treponema
- Plasmodium
- Toxoplasma
- Trypanosomes
- EBV
- HSV-1
- HSV-2
- CMV
- VZV
- KSHV
- HIV
- HBV
- HCV
- HPV
40 Immunologic Response to Vaccines:
Primary immune response
Upon challenge with a microbe…
Live vaccines
Subunit or killed vaccines
Most vaccines
Best case scenario
Safety issues (2)
Herd immunity (2)
- takes 7-10 days
- in the absence of an actual infection, the cells become memory cells
a secondary response, which is much faster and more robust, is mounted and the infection is eliminated or disease is averted
induce antibodies as well as effector T cells
induce antibody responses
inducing a strong antibody response that can inactivate the toxin or prevent viruses from entering cells
prior infection (once) protects against subsequent infection
- acellular pertussis vaccine is now used instead of the killed whole pertussis vaccine, because there are many fewer side effects
- inactivated polio vaccine is used now instead of live attenuated polio vaccine
- when a large group of people are vaccinated, there is little reservoir for the infectious agent
- some live vaccines can be passed to other, non-vaccinated individuals
40 Vaccines not available for some of the world’s biggest killers (8)
Tuberculosis Malaria HIV Worm infections Diarrheal diseases Respiratory infections Sexually transmitted diseases Trypanosomal infections
