Unit 3 Eukaryal Microbe Pathogenesis Flashcards Preview

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Flashcards in Unit 3 Eukaryal Microbe Pathogenesis Deck (55):
1

Why are treatments against eukaryotic pathogens limited?

So what is preferred?

Our cells are eukaryotic

Avoid infection in the first place

2

Regardless of pathogen type, the microbe must gain access to a susceptible host, evade or overcome host defenses, get nutrients, and exit the body

!

3

Malaria is caused by a...

It is called (the microbe)

Protozoan (eukaryotic)

P. Falciparum

4

This microbe needs to infect two or more species to complete its life cycle

P. Falciparum

5

Female mosquitoes for malaria serve as the ____ host, where sexual replication occurs in the salivary glands and is released as it starts to take blood meal

Definitive Host

6

Humans in malaria serve as _____ hosts, asexual replication and differentiation occur here

Intermediate Hosts

7

Can mosquitoes get infected by a malaria infected human?

Yes, part of its life cycle

8

This protozoan is simpler, the life cycle is in a single species. Cysts in contaminated water are ingested. Cramps and violent diarrhea are symptoms.

G. Lamblia (Giardia)

9

Cysts from giardia develop within human into

These replicate in the small intestine and produce new cysts in the ____

New cysts are eliminated in the host's

Trophozoites

Large Intestine

Feces

10

Animals tend to be more tolerant of the g. lamblia pathogen. It's more persistent in humans.

Rarer in more developed areas of the world (no water sanitation)

!

11

What is the other name for giardia?

Beever Fever

(their fecal material is in the water supply because they damn it, has cysts)

12

Some eukaryal microbes only cause disease if the immune responses are

What are some examples?

impaired (immunocompromised)

HIV/AIDS, or immunosuppression from drug therapies or another disease state

13

Is AIDS only caused by HIV?

No, it is an immunodeficiency syndrome that can be caused by radiation, chemicals, chemotherapy, or autoimmune disorders coupled with meds

14

This disease is caused a yeast fungus, yeast is usually part of our normal flora. It is an opportunistic infection associated with AIDS that leaves a white coating around the lips

What is the name of the microbe?

Thrush

Candida Albicans

15

If a baby is infected with cadida albicans (thrush), it should go away eventually with treatment. In adults, it probably means they are

Immunocompromised

16

This is a type of fungi that causes pneumonia, but rarely in healthy individuals. It can even be a part of their normal flora. Only occurs in immunocompromised individuals (HIV infected)

Pneumocystis jirovecii

17

This is a protozoan that can lead to taxoplasmosis, causes encephalitis in immunosuppressed individuals which is much more severe. Associated with a cat's fecal material. Dangerous if you're pregnant, can cross placenta and infect the baby.

Taxoplasma gondii

18

This is a protozoan associated with gastroenteritis, again a bigger problem if you're immunosuppressed, leads to chronic violent diarrhea

Cryptosporidium muris

19

This is a method eukaryal pathogens use of periodically changing/switching surface proteins on the immune system which confuses and delays immune responses. Difficult to make a vaccine

What protozoans exhibit this evasion strategy?

Antigenic Variation

Trypanosomes

20

These two trypanosomes are associated with chronic and acute sleeping sickness

Spread by the ___ fly

Trypanosoma brucei gambiense (Chronic)

Trypanosoma brucei rhodesiense

Tsetse Fly

21

This trypanosoma is spread by the kissing bug, that causes chagas disease which damages the heart and vital organs, can lead to death.

Tyrpanosoma cruzi

22

This trypanosoma is caused by a sandfly and causes dermal leishmaniasis, affects the skin

Leishmania major

23

Malaria, caused by ____, ultimately causes the death of red blood cells aka ____ in humans as infecting them is part of its life cycle. Inflammation (fever,aches, pains) can become a large problem as well as anemia, clogged capillaries, among other things which cause tissue damage

P. Falciparum

Erythrocytes

24

Malaria is a global problem, 300-500 million people are infected per year and 1 million die from malaria each year

In the US, when was malaria a big problem?

How did they get rid of it?

!!

The Civil War

Chemicals and dumping oil in mosquito reservoirs (things we can't do now)

25

In the replication of plasmodium falciparum, within humans, ______ are released (burst out) from infected erythrocytes and ingested by feeding mosquitoes

Gametocytes

26

Within mosquitoes, gametocytes differentiate in gametes, fuse and form a diploid ookinete which forms an oocyst and undergoes meiosis, producing haploid

Sporozoites (this is the important part to remember)

27

These can be transmitted to humans when an infected mosquito bites

Sporozoites

28

What do sporozoites initially infect?

They replicate to release _______, which ultimately infect erythrocytes and are later released as _____

Liver Cells

Merozoites

gametocytes

29

So in sum, what are released into human bloodstream via the mosquito salivary glands?

Sporozoites

30

The effects (symptoms) of P. Falciparum on humans is mostly a result of destruction of ____

Erythrocytes (red blood Cells)

31

The destruction of red blood cells caused by P. falciparum leads to

Anemia

32

How does the p. falciparum parasite (merozoites) attach to the red blood cells?

Merozoite surface proteins (MSPs)

Suggests a method for treatment

33

Mutant or deficient forms of MSPs limit the invasive potential of P. falciparum strains

!

34

Once inside an erythrocyte, merozoites obtain hemoglobin from the host cell through their

Digestion of hemoglobin releases

Cytostomes (protozoan version of a mouth)

Heme (iron part)

35

The merozoitic parasite converts heme into nontoxic

Hemozoin

36

What's the best route to prevent infection with P. falciparum

Getting rid of the mosquitoes

For example, insecticide treated mosquito blocking sleeping nets to prevent the transmission of P. Falciparum

37

This antimalarial drug blocks the formation of hemozoin, leaving a toxic com,pound in the parasites

Is resistance becoming a problem?

Better understanding of ___ may yield better treatments

Better diagnostic tools may provide earlier treatment with better outcomes

Chloroquine

Yes.

MSPs

38

What is the other treatment for malaria that isn't chlorquine

Vaccines.

39

These are macroscopic parasites that are not miscroscopic, but their eggs or larvae are. They share many attributes of their microscopic eukaryal pathogenic counterparts

Helminths (worms)

40

Do helmints need to enter, attach, and obtain nutrients?

They tend to cause disease as the obtain _____

Yes

Food (from the individual)

41

This is the most common worm, can cause intestinal blockage. Places with little access to medical care it is especially harmful

Roundworm

42

This helminth leads to organ damage in the digestive tract

Schistosomes

43

This worm causes elephantiasis by blocking the lymph vessels, where tissue fluids accumulate

Lymphatic Filariae

44

This is the infection caused by the roundworm that infects over 1.5 billion people

What route is it spread through?

Ascariasis

Fecal Oral Route

45

Where do the pathogens of ascariasis (roundworm) typically mature, which affects the host's (human's) ability to absorb nutrients

The small intestine

46

Ascariasis typically manifests as.....

slower growth and decreased weight gain in children! Big problem in countries where there is limited food, especially bad in children because of their increased base metabolic rate

Can also lead to life threatening situation by blocking the intestine

47

What would lead to less infection of the roundworm?

Sanitation/sewage treatment

48

People that get infected with roundworms, etc have less autoimmune disorders of the gut like Crohn's disease.

!

Can treat autoimmune disease by adding eggs of worms that don't ultimately cause infection

49

This is an infection in over 200 million people worldwide caused by the larvae of the flatworm. Long term infections can damage organs via inflammation, resulting in malnutrition and devopmental problems. Transmission can occur via contaminated water

Schistosomiasis

50

Is the life cycle of schistosoma sp more or less complex than ascaris?

Why?

More complex

Freshwater snails are an intermediate host

51

Can eukaryal pathogens affect evolution?

Yes

52

What is the example of humans and evolution in response to eukaryal pathogens?

What type of evolution is it?

P. Falciparum (malaria)

Co-evolution

53

THis disease results from hemoglobin mutation. Under certain conditions, red blood cells take on an abnormal shape leading to their destruction

Sickle Cell Disease

54

Why is the sickle cell trait widely carried in genomes of individuals of African and Mediterranean descent?

Malaria can't infect people with sickle cell of heterozygous individuals because they are protected from it

55

If you have both normal genes for Hb, are you more or less susceptible to malaria?

If you have both genes for sickled Hb, what occurs?

If you have heterozygous genes, what occurs?

More.

Sickle Cell disease (less flexible red blood cells that clog the capillaries)

You are immune to sickle cell but carry the gene for sickle cell disease