advanced micro final exam

chp 15-18, 21-24

what’s the difference between a sign and a symptom?

• sign: something that’s observed externally (ex: temp, color, heart rate)

• symptom: something that’s observed internally (ex: pain, nausea)

based on the name, what does dermatitis refer to?

***

what makes a disease: infectious, communicable, and contagious?

• infectious: caused by direct effect of a pathogen

• communicable: capable of being spread from person to person

• contagious: easily spread from person to person

describe a scenario that could lead to a patient contracting an iatrogenic disease

catherization is perfomed on an elderly patient. the provider accidentally contaminated their sterile gloves by touching a non sterile tray. they don’t change gloves and insert the catheter into the patient’s body. the bacteria from the catheter enters the patient’s body and ultimately forms the iatrogenic disease

• diseas contracted as the result of a medical procedure

describe a scenario that could lead to a patient contracting a nonsomical infection?

catherization is performed on a patient with a bloodstream infection but improper aseptic technique was used. the provider may have touched non sterilized objects in the area or didn’t frequently wash hands. this can cause sepsis

• infection acquired in hospital setting

rabies is transmitted when an infected animal bites a human. therefore, rabies is a…?

zoonotic disease

what are Koch’s postulates set up to determine? where does Koch fall short?

• four experimental critertia used to determine if a microorganism is a causative agent for a specific disease

• one pathogen does NOT cause one disease → one gene cause one disease

what is the difference between pathogenicity and virulence?

• pathogenicity: ability of a microbial agent to cause disease

• virulence: degree to which an organism is pathogenic

how are median infectious dose (ID50) and median lethal dose (LD50) calculated? does a pathogen with a low value for ID50 always have a low value for LD50?

• median infectious dose (ID50): # of pathogen cells/virions required to cause an active infection in 50% of inoculated animals

• median lethal dose (LD50): # of pathogen cells, virions, or amount of toxin required to kill 50% of infected animals

• a pathogen with a low value fro ID50 does NOT always have a low value for LD50

SARS-CoV-2, the causative agent of COVID-19, can cause disease whether a person has a robust microbiome and immune system or not. Is SARS-CoV-2 a primary pathogen or an opportunistic pathogen?

primary pathogen

primary pathogen vs. opportunistic pathogen

• primary pathogen: cause disease in a host regadless of resident microbiota or immune system

• opportunistic pathogen: cause disease in situations that compromise the host’s defense

Clostridium difficile is often present in the gut microbiome without causing disease. However, when a person depletes their microbiome after prolonged use of antibiotics, C.difficile can rapidly take over the gut and cause illness. Is C. difficile a primary pathogen or an opportunistic pathogen?

opportunistic pathogen

what are the stages of pathogenicity, in order?

1. exposure (contact): pathogen comes in contact with the host thru portal of entry (mucosus membrane of respiratory tract, GI, GE)

2. adhesion: pathogen attaches to cells of the body using adhesins

3. invasion: pathogen produce exoenzymes/toxins that aid in damaging host tissues

4. infection: pathogen overcomes immune defense and infects the host

a patient who recently had the flu has come to your clinic with a bad case of bacterial pneumonia. It seems that the recent flu infection they had led to a decrease in their immune defenses of their respiratory tract. What type of infection is the bacterial pneumonia in this case—primary or secondary?

secondary infection (infection stems from primary)

primary vs. secondary infection

• primary infection: caused by one pathogen

• secondary infection: caused by another pathogen somtimes stem from a primary infection

Enterohemorrhagic Escherichia coli produces a particular protein on its fimbriae that allow the cells to attach to the mannose glycans expressed on intestinal epithelial cells. What type of virulence factor is it using in this example?

adhesion

what is adhesin?

a protein or glycoprotein found on the surface of a pathogen that attaches to receptors on a host cell

hyaluronidase is secreted by Clostridium perfringens in order to degrade hyaluronic acid. What kind of virulence factor is Hyaluronidase, specifically?

a spreading factor that’s used to degrade hyaluronic acid (breakdown the gate)

which kind of bacterial toxin is produced by many gram-negative bacteria, is toxic in high doses due to its triggering of a large immune response, and is composed of a lipopolysaccharide?

endotoxin (lipopolysaccharide found on the outer membrane of gram-negative bacteria)

which type of exotoxin is composed of two subunits: one to bind to host cells and one to interfere with an intracellular target?

intracellular targeting toxins:

• A subunit (active): enters the cell cytoplasm and inteferes with specific internal cellular function it targets

• B subunit (binding): cellular specificity of the toxin and mediates initial attachtachment of the toxin to specific cell receptors

how do bacteria that produce superantigens affect their host? what is the mechanism?

trigger a cytokine storm that can excessively produce cytokines that elicit a strong inflammatory response

→ causes life threatning high fevers, low blood pressure, multi-organ failure, shock, and death (harms host while keeping bacteria alive)

which virulence factor causes the alteration of surface proteins that prevent the host immune system from recognizing the pathogen?

antigentic variation

what’s the difference between morbidity and mortality?

• morbidity: state of being diseased

• mortality: death due to a disease

why aren’t disease prevalence and disease incidence always equal?

they measure different levels of diseases in populations

• prevalence: # or proportion of individuals with a particular illness in a given population at a point in time

• incidence: # or proportion of new casess of a disease in a period of time

contrast sporadic diseases, endemic diseases, epidemic diseases, and pandemic diseases

• sporadic diseases: are seen occasionally and without geographic concentration (ex: tetanus, rabies, plague)

• endemic diseases: are constantly present (at low levels) in a population in a particular geographic region (ex: malaria in certain regions)

• epidemic diseases: a larger than expected number of cases occurs in a short time within a geographic region (ex: COVID in 2019 or bad flu season)

• pandemic diseases: epidemics that occur on a worldwide scale (ex: COVID-19 by early 2020)

what is a notifiable disease? what is a physician’s responsibility when treating a patient who has a notifiable disease?

• notifiable (reportable) disease: diseass that’s considered to be of public health importance on a national scale

→ physician needs to legally report to state, local, or national public health authorities because of contagiousness and severity

Typhoid Mary was a cook who was believed to have infected 51-122 people with Salmonella typhi, several of whom died from typhoid fever. She carried Salmonella typhi asymptomatically. She cooked for several different families, contaminating the food through poor practices, then moving onto the next family. Describe this case in epidemiological terms. What type of source spread took place? What type of carrier was Mary? What was the route of transmission?

• common source spread: occurs when there is a single source for all individuals affected

• carrier type: healthy/asymptomatic → she harbored and shed Salmonella typhi bacteria in her body without showing symptoms

• route of transmission: fecal-oral route → bacteria from her GI tract transfers via unwashed hands into food/drinks she prepared

what distinguishes the innate nonspecific immune system from the adaptive specific immune system?

Provide an example of each of the following types of physical defense

Physical barrier
b. Mechanical defense
c. Microbiome

Chemical defenses produced _______________________ are produced by human cells.
An example is ________________________.

hemical defenses produced _______________________ are produced by cells in the
microbiome. An example is __

AMPs stand for _____________________ ___________________. One family of AMPs
are the ____________________, which are produced by epithelial cells throughout thebody as well as by cellular defenses like macrophages and neutrophils. These AMPs
combat microorganisms by damaging their plasma membrane

What are the main protein chemical mediators found in plasma?

__________-_____________ ______________ are produced in the liver and secreted
into the blood in response to inflammatory molecules from the immune system

What are the three ways the complement system can be activated?

What are the 4 main results of complement activation?

What is the main function of cytokines, and how is this broken into 3 categories? (hint,
think about how they’re like hormones of the immune system)

a. main function

b

c

d

what is the main function of chemokine (a type of cytokine) ?

how do Type I interferons defend against viruses ?

where are leukocytes formed

______________________ are leukocytes characterized by a lobed nucleus and
granules in the cytoplasm. These include _______________________,
____________________, ______________________

How do neutrophil extracellular traps (NETs) work?

How are mast cells similar to basophils? How are they different?

How do natural killer cells “know” which cells to kill?

What is apoptosis?

The largest of the white blood cells are the _________________. When these cells leave
the bloodstream and enter a specific body tissue, they differentiate into tissue-specific
phagocytes called ________________ and __

how do phagocytes destroy pathogens?

Recognition of pathogens often takes place by the use of phagocyte receptors that bind
molecules commonly found on pathogens, known as _______________-
________________ ________________

how do leukocytes mive from blood vessel into tissues ?

what are the steps. of phagocytosis?

what are the 5 signs of inflammation

Which is stronger and faster—the primary response or the secondary response of adaptive
immunity?

The two major cell types involved in adaptive specific immunity are _______________,
which mature in bone marrow, and __________________ which mature in the thymus

what’s the difference between humoral inmmunit y and cellular immunity

how are antigens similar to PAMPs? how are they different?

Antigens typically contain multiple ____________________. These structures are what
are recognized by antibodies

what are the 5 primary functions of antibodies

_______________ _____________________ ___________________ is a collection of
genes coding for glycoprotein molecules expressed on the surface of all nucleated cells.

a. _____________ molecules are expressed on all nucleated cells and are essential
for the presentation of normal “self” antigens.
b. _____________ molecules are expressed only on the surface of antigen-
presenting cells. Antigen presentation of these molecules is essential for
activation of T cells.

how do antigen-presenting cells primarily destroy pathogens?

what are the 3 major classes of T cell and what is the main function of each?

what’s the difference between T cell receptors and B cell reeptos with respec to antigen recognition ze

what is the role of plasma cels in the adaptive specific immune sytem

what is antibody calss swithicng and why is it important

why does the primary response of the immune system have a longer lag period than the secondary response

what is herd immunity and hoe do vaccines fit into herd immunity

provide an example of each of the following mechanisms of acquisition of immunity

Natural active immunity
b. Natural passive immunity
c. Artificial active immunity
d. Artificial passive immunity

what is the risk associated with a live attenuated vaccine?

what types of vaccine result in long lasting immunity

why do some vaccines require more frequent boosters

describe the microbiome of the skin. What are the challenges members of your skin
microbiota face? What are 3 common microbes found here?

Describe the microbiome of the respiratory tract. What are the challenges members of
your respiratory tract microbiota face? What are 3 common microbes found here?

Describe the microbiome of the urogenital tract. What are the challenges members of
urogenital tract microbiota face? What is the major role of the healthy microbiota
members in the vagina?

Describe the microbiome of the digestive tract. What are the challenges members of your
digestive tract microbiota face? Why is the large intestine still prime real estate for so
many microbes?