Shared Flashcard Set

Details

Protozoa – Trypanosoma and Antigenic Variation
Human Para 3
96
Other
Undergraduate 4
12/18/2014

Additional Other Flashcards

 


 

Cards

Term
What is the kinetoplast?
Definition
Organelle found within mitochondria. Consists of DNA. Involved in metamorphosis
Term
Where is it located?
Definition
Inner surface of the mito membrane
Term
What are the two components of ktDNA and how are they arranged
Definition
Maxi circle and mini circle. Known as the concentrated mess-interconnected complex network.
Term
What are the three major kinetoplastid infections in humans?
Definition
HAT, Chagas disease, and Leishmanaisis
Term
What four morphological forms can occur in the various kinetoplastid life cycles?
Definition
amastigote, promasticgote, epimastigote, trypmastigote
Term
Does the amastigote have a flagellum?
Definition
No
Term
What is the kinetosome
Definition
Outer surface of the mito membrane - anchors the flagellum-gives rise to the kinetoplastid.
Term
What is the kinetoplast, where is it found, and what function does it have?
Definition
Organelle within the mitochondria that is in the inner surface of the mito membrane. It aids in metamorphosis.
Term
Does the amastigote have a nucleus?
Definition
Yes very posterior
Term
Does the promastigote have a flagellum?
Definition
Yes
Term
Does this form have an undulating membrane?
Definition
No
Term
Where is the promastigote found?
Definition
In insect vector and in culture
Term
Are the kinetosome/kinetoplast anterior or posterior to the nucleus in this form
Definition
Anterior
Term
Does the epimastigote have a flagellum?
Definition
yes
Term
Does this form have an undulating membrane?
Definition
yes
Term
Are the kinetosome/kinetoplast anterior or posterior to the nucleus in this form?
Definition
Anterior
Term
Does the trypomastigote have a flagellum?
Definition
yes
Term
Does this form have an undulating membrane?
Definition
yes
Term
Are the kinetosome/kinetoplast anterior or posterior to the nucleus in this form?
Definition
Posterior
Term
What the four basic types of this form
Definition
metacyclic,slender, stumpy,
Term
Into what two sections is the genus Trypanosoma divided
Definition
Section salivaria and sterocercaria
Term
Section Salivaria is also known as what?
Definition
anterior station developement.
Term
Species in this section develop in what part of the vector?
Definition
digestive tract
Term
Section Stercoraria is also known as
Definition
posterior setation
Term
Species in this section develop in what part of the vector?
Definition
hind gut
Term
Trypanosoma brucei is found in which section?
Definition
Salivaria
Term
What is the vector?
Definition
Glossina
Term
What stage of the parasite is infective to humans?
Definition
metacylic trypamastigote
Term
What stage lives in the blood of the human?
Definition
stumy tyrps- do not multiply
Term
Where do the trypomastigotes multiply
Definition
slender tryp- flies midgut
Term
What does its posterior end look like
Definition
blunt
Term
What stage is infective to Glossina?
Definition
stumpy tryp
Term
life cycle of T. brucei.
Definition
Glossina injects metacyclic tyrps to hosts slender tyrps in blood with bunt posterior end and undergo binary fissionstumpy tyrps are formed in blood that do not divide  ingested by glossina  develop into epimastigote become metacyclic tyrps and injected back into a human being.
Term
How many subspecies of T. brucei are there?
Definition
3
Term
How can they be differentiated?
Definition
Differ in their definitive host and the pathology that they cause
Term
What is the common name of Glossina? What does that name mean?
Definition
tsetse-destructive to cattle.
Term
How can this fly be identified?
Definition
meat cleaver cell on its wings
Term
Where in Africa is this fly most prevalent?
Definition
Tropical Africa btw 15 n and 15s fly belt
Term
What disease is caused by T. brucei brucei?
Definition
Nagana
Term
What animals are infected?
Definition
Livestock, antelope, no humans
Term
What two subspecies of T. brucei cause African Sleeping Sickness in humans?
Definition
T.B rhodisiense and T.B gambiense
Term
What are the differences in their morphology?
Definition
No differences
Term
What are the geographical distributions of T. b. gambiense and T. b. rhodesiense?
Definition
TBR- East Africa TBG- west Africa
Term
Which infects native game reservoir hosts?
Definition
T.B rhodesiense
Term
Which infects native game reservoir hosts?
Definition
T.B rhodesiense
Term
Which subspecies causes most cases of sleeping sickness
Definition
T.B gambesiense – west African Sleeping sickness.
Term
What are the two stages of human African trypanosomiasis?
Definition
1st- hemolymphatic stage. 2nd meningo-encephalic stage
Term
Where is the parasite found in each stage?
Definition
Hemolymphatic stage: parasite in peripheral circulate in lymph system enter tissue fluid
Meningo-encephalic stage : crosses blood brain barrier and enters the brain
Term
What happens in either infection if it is not treated?
Definition
TBR progresses rapidly –chancre sore at bite site most people develop a fever, experience headache, jot aches, enlarged lymph nodes
In ½ weeks after infection invades CNS neural deterioration, neurological problems, death within months.
TBG progresses more slowly After 1 or two years, CNS involvement personality changes, daytime sleepiness, confusion, partial paralysis, balance after three years death.
Term
What is the rate of disease progression in T. b. rhodesiense?
Definition
rapid
Term
What is the rate of disease progression in T. b. gambiense?
Definition
Progresses more slowly
Term
What is a chancre?
Definition
in tbr it’s a sore at the bite site
Term
What symptoms occur in each stage of infection?
Definition
TBR: chancre sore at bite site
Fever, experience headache, join aches, enlarged lymph nodes. W/in 1 or 2 weeks, invades CNS, neural deterioration, neurological problems, death within months.
TBG: progresses more slowly
Early in infection -: mild symptoms –malaise, lymph nodes swollen, weight loss
After 1 to 2 years CNS involvement, personality changes, daytime sleepiness, confusion, partial paralysis, balance
3 years - death
Term
What is Winterbottom’s sign?
Definition
Can be used for diagnosis. Swollen lymph nodes a base
Sign recognized by slave traders in slaves. These infected slaves were thrown overboard.
Term
In which subspecies is the parasite load in the blood higher?
Definition
TBR much easier to detect in blood=high load
Term
Why is serologic testing used only to detect T. b. gambiense infections?
Definition
Detection of antibodies. It is harder to detect it in the blood b/c the load is not that high.
Term
Why must cerebrospinal fluid be examined in all sleeping sickness infections?
Definition
To find if cns involvement has occurred. Determines which drug to be used.
Term
Who should receive treatment for sleeping sickness?
Definition
All positives. Untreated cases lead to death.
Term
What factors will determine which drug should be used?
Definition
TBG or TBR and disease stage.
Term
What are the four drugs which can be used to treat sleeping sickness?
Definition
1. Pentamidinne- drug that does not cross the blood brain barrier. Work in stage 2. Recommended for stage 1 and for tbg. Widely available in US.
2. Suramin: does not cross blood brain barrier
1st stage of tbg and tbr
Toxic
anaphalytic shock
Kidney failure
3. Melarsoprol = mel B – crosses the blood brain barrier
Last stage tbr and tbg

4. eflornithine – recent drug
Also crosses the blood brain barrier
Against tbg not tbr
AKA resurrection drug – wakes up people from comatose- expensive
Term
What is a drawback to using melarsoprol?
Definition
Has arsenic thus highly toxic
Term
Why is eflornithine known as the “resurrection drug”?
Definition
Awakens comatosed patients
Term
How long and why do patients require follow up examinations?
Definition
2 years
To prevent relapse
Term
What is the main method of prevention and control of sleeping sickness
Definition
Minimize contact with tsetse flies
Term
What type of clothing should be worn to minimize testes fly bites?
Definition
Long sleeves/long pants/neutral colors
Term
Why are tsetse flies often found inside vehicles?
Definition
Flies are attracted to motion and dust
Term
What is sterile insect technique?
Definition
Lab raised flies. Male flies are sterilized via irradiation helps eliminate fly population.
Term
What is antigenic variation?
Definition
Major obstacle in vaccine development. Tryps can hide from host immune system by disguising itself as one of the host cells. Long slender tyrps have surface coat that consists of single protein= varian surface glycoprotein. Tryps multiply in blood and host mounts effective immune response against tryps with particular VSG . removes almost all of the parasite with tht VSG coat. 41% of the tryps survive – posess variant VSG – temporarily unrecognized
Term
The surface coat of T. brucei blood trypomastigotes consists primarily of a single protein which is known as the
Definition
VSG_-varient surface glycoprotein
Term
Does the immune system recognize this protein
Definition
Yes
Term
Does the immune response remove all of the parasite
Definition
Nope.
Term
If not, how many are left?
Definition
41% left
Term
How are the waves of infection produced?
Definition
new varient
Term
Draw a graph with numbers of trypomastigotes on the y-axis and time on the x-axis to describe the relationship between the trypomastigote population and the host immune response.
Definition
Looks like a bell curve – the unrecognized tryp goes up and then finally is recognized and the number comes down.
Term
What is a variant antigenic type?
Definition
Each population that survives with VSG genes, only one at a time.
Term
How many genes are involved in antigenic variation?
Definition
1000 VSG genes
Term
Trypanosoma cruzi is found in which section?
Definition
Stercoceria
Term
What is the vector?
Definition
Kissing bug - cone nosed bug
Term
What stage of the parasite is infective to humans?
Definition
Metacyclic trypomastigotes
Term
How does the parasite enter the human?
Definition
When host scratch or rub fecal droplet containing 1000s of metacyclic trypomstigotes.
Term
What is the intracellular stage of the parasite?
Definition
Enter cells and become amastigotes enter spleen, liver, lymphatics, and all muscle.
Term
What stage is infective to the vector
Definition
Trypomastigotes
Term
life cycle of T. cruzi.
Definition
Kissing bug takes blood meal, swells up and defecates on the skin with metacyclic trypsenter host and transform into amastigotes and enter spleen, liver, lymphatics, and all muscle, amstigotes go through binary fission  only stage that multiplies in mammalian host (if in cardiac cluster, amastigotes are called pseudocyst)  host cell lyses, amstigotes released and invade other cells , some amstigotes transform in blood which is infective to vector, in vector- epimastigotes in midgut multiple, move to hindgut and transform into metacyclic tryps.
Term
What is distinctive about the posterior end and kinetoplast of T. cruzi trypomastigotes?
Definition
Pointed kinetolast and large posterior.
Term
Is this species capable of antigenic variation?
Definition
No tryps can be destroyed by antibodies
Term
How does this affect the number of trypomastigotes in the blood?
Definition
Very low number in blood as they are actually in cells in the amstigote form.
Term
What is a chagoma?
Definition
Acute infection causes local inflammation at the site of the bite.
Term
What is Romana’s sign?
Definition
Acute infection in which metacyclic trps enter eye, cause edema of eyelids and conjunctiva and result in fever swelling of lymh glands, fatigue, anemia,
Term
What is a pseudocyst?
Definition
If an amastigote is found in cardiac muscle cell, cluster of amstigotes in cardiac muscle.
Term
What symptoms are associated with the acute stages of T. cruzi infection?
Definition
chagoma and ramona’s sign
Term
What is the common outcome of infection in children?
Definition
What is the common outcome of infection in children?
Term
What organs are most commonly affected in chronic infections
Definition
Musce cells intestinal tract esophagus, colon, heart
The amastigotes produce
Term
The amastigotes produce
Definition
neurotoxin which results in loss of muscle function
Term
What happens in the intestinal tract?
Definition
In smooth muscle, peristalisis is diminished with esophagus and colon losing tone.
Term
What are megaesophagus and megacolon?
Definition
Result from perstalisis diminished with esophagus and colon lose tone
Term
What happens in the heart?
Definition
Muscle don’t contract normal, enlargement and flabbiness decreased pumping, heart failure.
Supporting users have an ad free experience!