Unit 4 (Ch. 14, 15, 16, 17)

___________ is caused by a Gram-positive resident, Propionibacterium, which uses sebum as a nutrition source.

Acne

Which general category of drugs is the most selectively toxic?

Antibacterial drug

Antiviral drugs can be used to target which of the following steps in viral replication? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Assembly Uncoating Penetration

Choose the true statement(s) about gas gangrene and cutaneous anthrax. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Both diseases present with tissue necrosis due to the production of exotoxins. The bacteria responsible for each of these diseases are naturally found in soil and can cause disease by infecting a wound. Both diseases are caused by Gram-positive, endospore-forming rods.

Which of the following susceptibility tests is able to determine both the minimum inhibitory concentration and the minimum bactericidal concentration?

Broth dilution test

Which of the following statements regarding the CRISPR-Cas9 system is/are true? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

CRISPR-Cas9 is currently being investigated for use in correcting human genetic disorder such as hemophilia and sickle cell anemia. Binding of guide RNA to a target DNA sequence triggers the CRISPR-Cas9 system to cut the target DNA sequence.

Which of the following microorganisms are among the top three urgent drug-resistant bacterial threats to health in the United States? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Carbapenem-resistant Enterobacteriaceae (CRE) Clostridium difficile

Genetic and chemical modifications are often performed on antimicrobial drugs. Which of the following statements explains the advantage of performing such drug modifications? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Chemical modifications can allow for certain antimicrobial resistance mechanisms to be circumvented. Chemical editing may allow for enhanced drug production. Chemical modification may allow for extended drug capacities such as expanded spectrum of activity and increased stability.

Choose the true statement(s) regarding the characteristics of smallpox compared to the characteristics of chickenpox. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Chickenpox lesions are small, elevated and filled with a clear fluid whereas smallpox lesions are domed, solid, deep, and have a center dimple. Smallpox lesions tend to develop on the palms of the hands and soles of the feet, whereas chickenpox lesions often appear on the torso. Smallpox is caused by the variola major virus whereas chickenpox is caused by the varicella-zoster virus.

Which of the following statements describes why children are more susceptible to otitis media compared to adults? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Children have narrower Eustachian tubes than adults. Children have less efficient drainage of fluid from the Eustachian tubes into the throat.

Which of the following actions would most likely result in exposure to Hantavirus within the United States?

Cleaning a previously undisturbed barn known to house deer mice

The main causative agent of gas gangrene is ___________.

Clostridium perfringens

Which of the following describes why a drug may appear effective against a pathogen in clinical susceptibility tests but ineffective in a real-life context? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Compared to controlled susceptibility tests, the drug may be less active in a real-life context either due to drug inactivation by body processes or as a result of drug solubility issues. Unlike in controlled clinical susceptibility tests, the number of bacteria varies between tissue samples. In clinical susceptibility tests, drug concentration is well controlled compared to a real-life context.

Choose the true statement(s) about cutaneous candidiasis. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Cutaneous candidiasis is caused by the yeast species Candida albicans. Diabetics are more susceptible to cutaneous candidiasis due to high blood sugar levels, which promote yeast growth. Cutaneous candidiasis presents with a red macular rash that is itchy and burns.

Which of the following are primary mechanisms through which microorganisms evade antimicrobial drugs? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Drug target alterations Drug inactivation Reducing drug concentration inside of the cell

Which of the following is a valid challenge when designing new antimicrobial drugs? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Economically, there is little return on investment for discovering a new antimicrobial therapy. Identifying a new antimicrobial is a costly effort. Identifying new antimicrobials is a time-consuming process.

Select the Pseudomonas aeruginosa virulence factors. To be marked correct, you'll need to select all virulence factors, as there may be more than one correct answer.

Endotoxin production Make pyocyanin Metabolize detergents

Which of the following statements is/are true regarding viral delivery for gene therapy? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Engineered adenoviruses and retroviruses are the most common viruses used in gene therapy. Adenoviruses are less likely than retroviruses to integrate into a host genome, providing less potential for gene editing.

Which of the following anatomical sites is part of the upper respiratory tract? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Epiglottis Paranasal sinuses

Your patient has a stubborn case of athlete's foot. After treatment with an antifungal agent, you observe fungal cell lysis as a result of improperly built plasma membranes. Which of the following antifungal drugs was most likely used during treatment?

Fluconazole

Which of the following statements about the 1998 publication in The Lancet pertaining to autism and vaccines is true?

Following the publication, there was a drop in childhood vaccination rates in the United States and United Kingdom, and a subsequent increase in outbreaks of rare, vaccine-preventable diseases.

Which of the following statements accurately describes recombinant vector vaccine synthesis?

Genetic material from the pathogen is placed inside of a harmless virus, which is then introduced into the body.

Choose the true statement(s) about bacterial conjunctivitis. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Haemophilus influenza is one of the most common causes of bacterial conjunctivitis. Bacterial conjunctivitis presents with a green or yellow pus-like discharge.

Choose the true statement(s) regarding herpes simplex virus 1. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Herpes simplex virus 1 causes oral herpes and is characterized by cold sores. Herpes simplex virus 1 migrates to the trigeminal nerve and remains latent until subsequent reactivation.

An adult patient with an influenza infection can be distinguished from an adult patient with a common cold based on the presence of which symptom/sign of infection?

High, prolonged fever

Which of the following statements describes why sulfa drugs do not interfere with mammalian biological pathways?

Humans do not independently synthesize folic acid (the target of sulfa drugs), but acquire it from their diet.

Select the Streptococcus pyogenes virulence factors. To be marked correct, you'll need to select all virulence factors, as there may be more than one correct answer.

Hyaluronic acid capsule M-protein

Which of the following techniques relies on the use of fluorescent-tagged antibodies? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Immunofluorescence assay Flow cytometry

Which of the following statements describe (an) advantage(s) of performing an immunological test over a biochemical test? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Immunological tests can be used for pathogens that are difficult to culture in a laboratory. Immunological tests take less time to perform than biochemical tests. Immunological tests can identify obligate intracellular parasites such as viruses.

Which of the following is/are caused by Staphylococcus aureus? To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Impetigo Scalded skin syndrome Cellulitis

Which of the following is/are caused by Streptococcus pyogenes? To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Impetigo Toxic shock syndrome Necrotizing fasciitis

Which of the following actions should be taken to limit the spread of antimicrobial resistance? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

In developing countries, healthcare agencies should have increased regulation of antimicrobial drug use. Increased handwashing practices and consistent use of aseptic techniques should be performed in healthcare settings.

Choose the true statement(s) about leishmaniasis. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

In visceral leishmaniasis, the pathogen disseminates throughout the body. In mucocutaneous leishmaniasis, lesions develop in mucous membranes of the nose or mouth.

Which of the following agricultural practices may promote antimicrobial drug resistance? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Including antimicrobials in animal feed Use of manure-based fertilizers Use of manure-contaminated water

Choose the true statement(s) regarding the impact of the MMR (measles, mumps, rubella) vaccine. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Infants who are unable to be vaccinated are not protected against measles unless a high percentage of the population is vaccinated with the MMR. Prior to the availability of a measles vaccination, between 3 and 4 million people in the U.S. contracted measles each year. Before the MMR vaccine, each year there were about 1,000 cases of chronic disabilities due to measles encephalitis.

Which of the following signs and symptoms can be observed during progression of diphtheria? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Loss of consciousness Formation of a pseuodomembrane in the throat Bull neck

Which of the following is not a Staphylococcus aureus virulence factor?

M-protein Correct: Coagulase, A polysaccharide capsule, Exfoliative toxin

Walking pneumonia is a respiratory illness caused by Mycoplasma pneumoniae. M. pneumoniae is a unique bacterial pathogen in that it lacks a cell wall. Based on the microorganism's unique properties, which of the following drugs could be an appropriate treatment for a patient with walking pneumonia?

Macrolide

Which of the following antiprotozoan drugs could be given to a patient suffering from toxoplasmosis?

Metronidazole

During a pertussis infection, the pathogenic bacterium Bordatella pertussis produces tracheal cytotoxin, which destroys cilia. Which of the following would most likely result from ciliary destruction?

Mucus would accumulate in the respiratory tract.

Your elderly patient presents with shortness of breath, fever, wheezing upon inhalation, and chest pain. Her case history reveals that her symptoms were preceded by cold-like symptoms and a persistent dry cough. Based on her initial symptoms, penicillin (an antimicrobial drug that hydrolyzes peptidoglycan found in bacterial cell walls) was prescribed and shown to be ineffective. A sputum sample taken from the patient reveals that the pathogen does not have a cell wall. Based on this information, which of the following pathogens is most likely the causative agent of the infection?

Mycoplasma pneumoniae

Bacitracin is made naturally by the bacterium Bacillus subtilis and is primarily only used to target skin infections caused by Gram-positive bacteria. This type of chemotherapeutic drug would best be characterized as a(n) ____________.

Narrow-spectrum antibiotic

Which of the following routes of drug administration is ideal?

Orally

Which of the following is/are caused by Pseudomonas aeruginosa? To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Otitis externa Wound infections

Your patient has sinusitis, and the bactericidal drug Augmentin (amoxicillin and clavulanic acid) is given as treatment. Which of the following is a valid concern when using this drug? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Overgrowth of pathogens such as Clostridium difficile due to killing of normal flora Drug-induced liver injury

Which of the following is an example of an antibiotic?

Penicillin G produced naturally by the mold Penicillium

Your 3-year-old patient presents to you with high fever, shaking chills, cough, chest pain, and shortness of breath. The patient's mother stated that symptoms began suddenly last night. The patient is up to date on all vaccinations. Based on this information, which of the following diseases did your patient most likely contract?

Pneumococcal pneumonia

Which of the following is the mode of action through which polymixin B kills bacterial cells?

Polymixin B disrupts outer membrane and plasma membrane structure.

Which of the following is incorrectly paired? To be marked correct, you'll need to select all incorrectly paired statements, as there may be more than one correct answer.

Primary lesion: Indirectly associated with a disease and have diverse origins; Vesicular rash: rash of large purple spots that evolve from bleeding in skin layers (subcutaneous bleeding); Ulcer: Type of primary skin lesion Correct: Maculopapular rash: Seen in rubella, this rash features small slightly raised lesions that overlay or are interspersed with flat discolored areas of the skin.

Choose the true statement(s) about keratitis. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Protozoan keratitis is caused by Acanthamoeba. Keratitis is severe inflammation of the cornea. Keratitis can be caused by viral, bacterial, fungal, and parasitic species.

Which of the following statements provides the best definition for the term herd immunity?

Provided that a sufficient percentage of the rest of the population is vaccinated, non-vaccinated individuals, such as premature babies and immune-compromised patients, have protection against various diseases.

Which of the following primary skin lesions is a raised lesion that contains pus and is found below the skin surface?

Pustule

Praziquantel is an antihelmnithic drug that works through which of the following mechanisms of action?

Pyrantel paralyzes the parasite, allowing it to detach from host tissues.

Your 10-month-old, pediatric patient presents with sore throat, runny nose, difficulty breathing, tachycardia, and wheezing. The patient received an effective influenza vaccine 4 months ago. Upon evaluation with a stethoscope, crackling is heard during inhalation. Nucleic acid probes reveal that the pathogen has an RNA genome. Your patient is most likely afflicted with which of the following illnesses?

Respiratory Syncytial Virus (RSV)

Which of the following methods is/are needed in order to successfully generate and propagate recombinant DNA? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Restriction enzyme digests of both the vector and target DNA sequence Transformation of recombinant vector into a suitable host

Human Immunodeficiency Virus-1 (HIV-1) is an RNA virus with a long incubation period. Due to the long time needed for disease symptoms to develop, disease progression can alternatively be measured by detection of HIV genetic material in the bloodstream of infected patients. Which of the following molecular methods would be most appropriate for disease detection of HIV-1 in patient's bloodstream?

Reverse-transcriptase polymerase chain reaction

Which of the following is the mechanism through which rifampin works?

Rifampin blocks RNA polymerase, preventing transcription.

Which of the following diseases is incorrectly matched with its characteristics?

Roseola: rare childhood infection that tends to present without a fever Correct: Fifth disease: caused by a parvovirus and presents with a red facial rash; Hand, foot, and mouth disease: mild disease that is mainly caused by coxsackievirus A16 and enterovirus 71; Rubella: also known as German measles and presents with a rash and swollen lymph nodes

Which of the following statements is true concerning severe acute respiratory syndrome (SARS)? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

SARS has an incubation of between 2-10 days. The 2003 SARS outbreak had a mortality rate of roughly 10 percent.

You wish to set up a DNA microarray to study which genes are implicated in breast cancer. You fluorescently label normal breast tissue with a green fluorophore and tumor breast tissue with a red fluorophore. You see that your gene labeled SASH1 fluoresced green while your gene labeled HER2 fluoresced red. Taken together, these results indicate that:

SASH1 is underexpressed in breast cancer patients, whereas HER2 is overexpressed is breast cancer patients.

Which of the following is desirable in an ideal drug? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Selective toxicity Oral administration

Which of the following statements concerning restriction enzymes is true?

Some restriction enzymes generate overhangs in the target DNA sequence upon digestion, whereas other restriction enzymes perform blunt cuts.

Upon performing a Kirby-Bauer disc diffusion test using Staphylococcus aureus, you observe no zone of inhibition with penicillin and a 15mm zone of inhibition with vancomycin. Based on these observation, which of the following conclusions is valid?

Staphylococcus aureus is resistant to penicillin but may or may not be sensitive to vancomycin.

Choose the true statement(s) about the skin's normal microbiota. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Staphylococcus species are prevalent on the skin. Normal microbiota reside on the epidermis as well as in sweat glands and sebaceous glands. Pseudomonas species are prevalent on the skin.

Which of the following diseases is caused by Streptococcus pyogenes? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Streptococcal pharyngitis Scarlet fever Impetigo

Which of the following mycoses is/are the most pressing to treat? To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Subcutaneous mycoses.

Which of the following is needed in order to perform a direct ELISA? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Substrate Enzyme-linked detection antibody

A strain of Chlamydia trachomatis appears to have acquired a mutation in the 30S (small) ribosomal subunit, preventing drug binding. Other than the mutation in the small ribosomal subunit, its ribosome structure appears otherwise unchanged. Based on this mutation, which of the following drugs would you expect to see decreased efficacy with this mutant strain?

Tetracycline

Which of the following statements is true regarding the 1918 Spanish influenza? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

The 1918 Spanish influenza was one of the deadliest influenza pandemics. The increased mortality observed in the young adult population infected with the 1918 Spanish influenza was most likely due to an overwhelming immune response resulting in cytokine storms.

Unlike the Kirby-Bauer disc diffusion test, the E-test can provide which of the following information?

The E-test can provide the minimum inhibitory concentration for a given drug.

Which of the following is an example of intrinsic resistance?

The bacterium Bacillus cereus produces endospores during environmentally harsh conditions, enabling it to survive cooking processes.

Choose the false statement(s) about the eyes. To be marked correct, you'll need to select all false statements, as there may be more than one correct answer.

The cornea is a transparent membrane that covers the eyeball and lines the eyelids. The eyes do not harbor resident microbiota. Correct: Resident microbiota of the eyes include Staphylococcus and Corynebacterium. Tears include lysozyme, which breaks down bacterial cell walls.

Which of the following statements is true concerning Alexander Fleming and his antimicrobial discovery?

The first antibiotic was discovered by accident when a contaminating mold killed a culture of Staphylococcus aureus.

Upon performing a Mantoux tuberculin skin test, a 15-mm zone of induration is observed. The patient has a normal chest X-ray and does not report feeling ill. The vaccination history of the patient is unknown. Which of the following scenarios explains the patient's test results, given her case history? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

The patient has latent tuberculosis. The patient has been vaccinated against tuberculosis.

Which of the following statements concerning the early history of vaccinations is true?

The practice of variolation involved blowing a powder made of dried scabs of smallpox lesions into a healthy individual's nose.

Which of the following statements concerning adjuvants is true?

The precise mechanisms that adjuvants use to increase immunogenicity are not yet fully understood, but adjuvants may stimulate cytokine release and encourage antigen uptake and processing by antigen-presenting cells

Choose the false statement(s) about protective skin characteristics. To be marked correct, you'll need to select all false statements, as there may be more than one correct answer.

The skin's high pH and low salt concentration are effective weapons against microorganisms.

Which of the following statements regarding immunoprecipitation reactions is true?

The zone of equivalence in an immunoprecipitation reaction is the area where there is an equal or roughly equal amount of antigen and antibody molecules.

Choose the true statement(s) regarding chickenpox. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

There are vaccines against chickenpox and shingles. Chickenpox is caused by a herpes family virus (Herpesviridae family).

Choose the true statement(s) regarding ways that Streptococcus pyogenes can be differentiated from Staphylococcus aureus. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

These organisms can be differentiated by the catalase test. These organisms can be differentiated by using a microscope to view their cell arrangement.

Which of the following dermatophytic infections are correctly matched with their afflicted skin region? To be marked correct, you'll need to select all correctly matched statements, as there may be more than one correct answer.

Tinea corporis is a body-wide skin infection. Tinea cruris is an infection of the groin.

________________ is caused by a Chlamydia species and is the leading cause of preventable microbial blindness.

Trachoma

Which of the following measures demonstrates a minimum inhibitory concentration (MIC)?

Using an E-test, the MIC is the point on the strip that intersects the start of the zone of inhibition.

Which of the following statements concerning vaccinations is correct?

Vaccinations stimulate immunological memory, allowing for a strong secondary response.

Your patient has osteomyelitis caused by a strain of Staphylococcus aureus (a Gram-positive bacterium) that naturally produces beta-lactamase. Which of the following treatments would be the most effective?

Vancomycin

Choose the true statement(s) about warts. To be marked correct, you'll need to select all true statements, as there may be more than one correct answer.

Warts are a result of deregulated host cell division that causes abnormal cell growth. Warts are spread by direct contact. Warts are caused by viruses.

Which of the following is a classic sign of croup?

Wheezing or loud breathing associated with a blocked or narrowed airway

Gene maps can reveal which of the following types of information? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.

Which genes are needed for normal cellular function Quick identification of a gene that encodes a desired protein for gene cloning How virulence factors are acquired through horizontal gene transfer mechanisms

You inoculate a nasal swab from an otherwise healthy patient onto a general-purpose medium and incubate the sample at human body temperature. After a sufficient incubation period, which of the following would you most likely observe?

You should observe predominantly Firmicutes such as Staphylococcus sp. growing on the general-purpose medium.

Which of the following results would you expect from an interferon-gamma release assay from a patient suffering from an active tuberculosis infection?

You would expect T lymphocytes to release high levels of interferon gamma.

Your pediatric patient presents with severe coughing fits with intermittent gasping for air. Two weeks prior to his clinical presentation, your patient exhibited common cold symptoms such as runny nose, watery eyes, and moderate cough. Based on the patient's case history, which of the following statements is most likely true for the progression of disease in this patient?

Your patient will most likely have intense coughing fits for up to one additional month, followed by less frequent coughing spells the following month.

In which of the following scenarios may a bactericidal drug be chosen over a bacteriostatic drug?

Your pediatric patient has bacterial meningitis caused by the Gram-positive bacterium Streptococcus agalactiae.

In one variation of the influenza vaccine, hemagglutinin and neuraminidase are isolated from the viral particle and are then mixed with GEM particles, an adjuvant. This type of vaccine is known as a(n):

purified, subunit vaccine.

You perform a plaque reduction neutralization test on a patient who is recovering from a suspected case of Dengue fever, caused by Dengue virus. You observe that there is increased number of plaques on the test plate compared to the control. These results indicate that:

the patient lacks antibodies to Dengue virus.