Quiz 6 Key (Merged) PDF

Q1. The infectious dose of Francisella tularensis is approximately this many bacteria A. ~10< B. ~100 C. ~1,000 D. ~10,000 Q2. Intracellular Legionella pneumophila prevent lysosome fusion by manipulating this process inside a macrophage: A. Exocytosis B. Autophagy< C. Transcription D. Pha...

Q1. The infectious dose of Francisella tularensis is approximately this many bacteria A. ~10< B. ~100 C. ~1,000 D. ~10,000 Q2. Intracellular Legionella pneumophila prevent lysosome fusion by manipulating this process inside a macrophage: A. Exocytosis B. Autophagy< C. Transcription D. Phagocytosis E. Protein synthesis Q3. What type of device in a local (to Blacksburg) home improvement store was responsible for transmitting Legionella pneumophila to customers in 1996? A. Air conditioning unit B. Drinking fountain C. Wood mulcher D. Plant misting system E. Hot tub < Q4. Legionella pneumophila can be spread from person-to- person by coughing and aerosolization of the bacterium. A. True B. False< Q5. Which capsule type of Haemophilus influenzae cause the most infections? A. A B. B< C. C D. D E. E Q6. Which toxotype of C. perfringens causes human enteritis necroticans (pig-bel)? A. A B. B C. C< D. D E. E Q7. Which Clostridial infection is highly associated with the patient having colon cancer? A. C. difficile B. C. botulinum C. C. perfringens D. C. tetani E. C. septicum< Q8. Tetanus toxin acts primarily at the: A. Spinal cord < B. Brain C. Neuromuscular junction Q9. The toxins Tox A and Tox B of C. difficile are enzymes. What type of chemical reaction do these toxins carry out? A. ADP ribosylation B. Phosphorylation C. Proteolysis D. Glucosylation< E. Dephosphorylation Q10. This food is commonly associated with infant botulism: A. Milk B. Rice C. Bread D. Fruit juice E. Honey< Q1. Which first-line antibiotic, that stops mycolic acid biosynthesis, is administered to people with M. tuberculosis? A. Penicillin B. Isoniazid < C. Streptomycin D. Clindamycin E. Erythromycin Q2. When growing intracellularly, M. tuberculosis reproduces in: A. T cells B. Macrophages< C. B cells D. Neutrophils E. Lung epithelial cells Q3. The C. diphtheria toxin carries out the ADP- ribosylation of what protein in the mammalian cell? A. Adenylate cyclase B. Gs C. EF-2< D. Rac E. Rho Q4. Which species of Mycobacterium can be transmitted to humans by drinking raw milk from infected cows? A. M. avium B. M. tuberculosis C. M. leprae D. M. intracellulare E. M. bovis< Q5. The BCG vaccine (Bacillus Calmette Guerin) was made from what species: A. M. avium B. M. tuberculosis C. M. leprae D. M. intracellulare E. M. bovis< Q6. Erythema migrans refers to the Lyme disease A. Arthritis B. Muscle weakness C. Bulls eye rash< D. Neurological symptoms E. Lack of mobility in joints Q7. Which antibiotic is currently used to treat most cases of syphilis. A. Clindamycin B. Isoniazid C. Streptomycin D. Penicillin< E. Erythromycin Q8. Genus of tick that most commonly transmits Lyme disease in the U.S: A. Pediculus B. Amblyomma C. Ornithodoros D. Ixodes< E. Dermacentor Q9. The first clinical sign of syphilis is the formation of this: A. Insanity B. Gummas C. Blindness D. Chancre< E. Paresis Q10. Spirochete flagella are located here: A. Outer surface B. Peptidoglycan C. Periplasmic space< D. Cytoplasm Legionella  Legionella L. pneumophila-Legionnaire’s Disease L. pneumophila and L. micdadei-Pontiac Fever Flu-like illness, not as serious Figure 21-1 Sources of legionellae for human disease. Figure 21-2 Electron micrographs. A. Uptake of Legionella pneumophila by a macrophage. B. At 4 hours after infection, a single organism in cross section is seen within an endosome that has associated with rough endoplasmic reticulum. Note the studding of the membrane with ribosomes (arrows). C. L pneumophila begin to multiply to large numbers within membrane-bound vesicles (membranes indicated by arrows). Figure 21-3 Key events in the life cycle of L pneumophila. L pneumophila in the flagellate, transmissive form survives in the cell. Survival depends on type II and IV secretion systems that deliver to the cytoplasm bacterial proteins that manipulate host cell biology. Instead of being delivered to lysosomes, the phagosome associates with endoplasmic reticulum in a process akin to autophagy (see text). In the presence of abundant nutrients, the bacteria convert to the noninfectious, replicative form and grow to large numbers in an ever-enlarging membranebound vesicle. Eventually, the depletion of nutrients in the cell activates the RelA and SpoT enzymes, which generate ppGpp. The ppGpp alarmone triggers the transcription of the transmissive phase genes that trigger release from the cell, motility (flagellation), and infectivity (altered trafficking) in the next host cell. Francisella tularensis Tularemia  F. tularensis Associated with animals-humans get accidentally exposed Highly infectious- ~10 bacteria – Found in animals in Northern Hemisphere Lives in macrophage in lymph nodes, causes swelling: – Ulceroglandular: 75-80% of cases Recent discovery- – Can escape the phagosome of macrophages  Haemophilus influenzae The cause of many diseases other than pneumoniae Gram stain Epiglottitis: Suffocation hazard, especially in children  Recap from Lecture 7 Children under two years old do not have an effective antibody response to carbohydrate antigens (i. e., T-cell independent antibody response). So, what do vaccinologists do to provide vaccines for childhood diseases caused by encapsulated bacteria? Lecture 16 Francisella tularensis Gram negative short rods Ð highly pleomorphic. Nonmotile; no flagella. Aerobic. Optimum temperature, 37¡C. Difficult to grow. Medium: blood-glucose-cystine agar. (Requires cysteine or cystine; either one is OK. Legionella requires cysteine and cannot use cystine.) May take up to 3 weeks to grow from clinical specimen. Highly contagious for laboratory personnel (like Brucella in this regard). Only takes as few as 10 cells to cause tularemia. Biosafety level 3. Tularemia Named after Tulare County, California, where organism first isolated in 1912. Disease is a zoonosis. Sources of F. tularensis: Found throughout Northern Hemisphere except for Great Britain. F. tularensis has been recovered from over 100 species of wild mammals Ð including rabbits, hares, squirrels, voles, muskrats, beavers, and deer. Also recovered from at least 9 species of domestic animals including sheep, cattle, and cats. Also isolated from birds, some amphibians and fish, and many arthropods (esp. ticks, deerflies, and mosquitoes). Also has been isolated from mud and from water from streams and wells. In the U.S., the most important sources for human infection are wild rabbits and hares, and ticks. Modes of transmission of F. tularensis: 1. (Major). Direct contact with the infected tissues or body fluids of an infected animal (usually a rabbit). 2. Arthropod vectors. 3. Aerosols 4. (rare) Ingestion 5. infections- Tularemia Ulceroglandular (75-80%) Oculoglandular (1-2%) Glandular (5-10%) Typhoidalb (5-15%) Pulmonary (rare; mainly lab infections) Oropharyngealc (rare) Additional Note: A skin rash may occur in up to 20% of cases of tularemia. Thus tularemia, especially with a history of tick bites, may mimic Rocky Mountain spotted fever, Lyme disease, or other diseases in which a skin rash is produced. Mortality rates: Without treatment, 30% With treatment,