Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

COM MOD 2.2 Viruses > Chapter 3.26 Retroviridae, HIV, and AIDS > Flashcards

Chapter 3.26 Retroviridae, HIV, and AIDS Flashcards

1
Q

What are the characteristics of retroviridae?

A

RNA viruses that infect animals and humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 3 big concepts unique to the retroviridae group?

A

Retro- carry reverse transcriptase the converts viral RNA into DNA that can integrate into the host DNA
Grow- oncogenic in humans and animals
Blow- cytotoxic to certain cells, blowing them up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does the Rous sarcoma virus work?

A

oncogenic virus that encodes a protein that phosphorylates tyrosine at ten times the normal rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What cancers are associated with most retroviridae?

A

leukemia and sarcoma

*sometimes called leukemia sarcoma viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is an acute transforming virus?

A

carry intact oncogenes in their viral genome which can integrate into host DNA and cause malignant trandformation
*use sticky ends and integrase enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the most common example of an acute transforming virus?

A

Rous sarcoma virus which has the oncogene src

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are non-transforming viruses?

A

retroviridae that activate host cell proto-oncogenes by integrating viral DNA into key regulatory area
*do not carry oncogenes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What virus is linked to tropical spastic paraparesis?

A

human T-cell leukemia virus (HTLV-1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the shape of human immunodeficiency virus (HIV)?

A

spherical, enveloped virion with cylindrical nucleocapsid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 3 essential retroviral enzymes of HIV?

A

protease, reverse transcriptase, and integrase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the major capsid of HIV?

A

p24 - which is measured in serum to detect early HIV infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the surface glycoproteins of HIV?

A

gp120 and gp41

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the main components of all retrovirus genomes?

A

long terminal repeats, gag gene, pol gene, and env gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the function of long terminal repeats in reverse transcriptases?

A

sticky ends to help insert into host genome and promoter functions to help promote viral DNA transcription

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the function of gag gene?

A

codes for virion’s structural proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the function of pol gene?

A

encodes protease, integrase and reverse transcriptase

**protease is essential for HIV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the function of env gene?

A

codes for envelope proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where is HIV/AIDS most common globally?

A

developing countries specifically Africa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How is the HIV virus transmitted?

A

parenteral route

  1. Sexual activity
  2. Blood product transfusion
  3. Intravenous drug use
  4. Transplacental (mother to fetus)
  5. Health Care providers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How can HIV spread through sexual activity?

A

HIV is present in seminal fluid and vaginal and cervical secretions
Anal intercourse causing rupture to thin rectal wall

21
Q

What lymphocyte is involved in HIV?

A

T helper cells with CD4 lymphocytes

*with co-receptor CCR5 or CXCR4

22
Q

What are the 3 stages of HIV/AIDS?

A
  1. Actue viral illness
  2. Clinical latency
  3. AIDS
23
Q

What is the clinical presentation of a patient with HIV/AIDS in the acute viral illness phase (1)?

A

*1 month after exposure
Symptoms similar to mononucleosis (fever, malaise, lymphadenopathy)
High levels of blood-borne HIV (viremia) that eventually decreases and resolution of symptoms leading to phase 2

24
Q

What occurs during the clinical latency phase (2) of HIV/AIDS?

A

*median of 8 years

HIV continues to replicate and there is a steady destruction of CD4 T helper cells

25
Q

What occurs during the last phase if HIV/AIDS?

A

*median of 2 years followed by death

AIDS develops

26
Q

What opportunistic infections usually only develop in AIDS patients?

A

Candida esophagitis, Pneumocystis carinii pneumonia, Kaposi’s sarcome

27
Q

What can be used to determine severity of HIV infection and prognosis?

A

CD4 counts and viral load

28
Q

What can viral load determine?

A

risk for opportunistic infection

*the higher the plasma HIV RNA levels the greater risk for opportunistic infection

29
Q

What is the hallmark of HIV?

A

gradual depletion of CD4+ T cells leading to weakened immune system and secondary opportunistic infections

30
Q

Why is destruction of CD4+ T cells so significant in HIV/AIDS patients?

A

Because T cells orchestrate activation and recruiting of B cells, macrophages, and neutrophils

31
Q

What are multinucleated giant cells?

A

T cell to T cell fusion allowing a virus (ex. HIV) to pass to infected cells without contacting blood

32
Q

How does HIV affect B cells?

A
  • causes hypergammaglobulinemia- polyclonal activation of B cells
  • causes inability to produce antibodies in response to new antigens
33
Q

How does HIV affect macrophages and monocytes?

A

HIV doesn’t kill them but uses them as reservoirs and macrophages and monocytes can migrate across the blood-brain barrier
*carrier HIV to the CNS

34
Q

What 2 processes occurs through the HIV virus to promote AIDS?

A
  1. Direct viral disease: widespread symptoms (constitutional) across the body and neurological damage
  2. Disease secondary to immunodeficient state: failure to prevent malignancies and increased opportunistic infections
35
Q

What is the constitutional symptoms of an AIDS patient?

A

night sweats, fever, enlarged lymph nodes, severe weight loss
*referred to as “the wasting syndrome”

36
Q

What are the neurologic symptoms in an AIDS patient?

A

encephalopathy resulting in decline in cognitive function (AIDS dementia), meningeal infection, infect the spinal cord, neuropathy of peripheral nerves

37
Q

What malignancies are commonly seen in AIDS patients?

A

B cell lymphoma- often presenting as a brain mass
Kaposi’s sarcoma- usually in homosexual men using HHV-8 (herpes virus)
Non-Hodgkin’s lymphoma, cervical cancer

38
Q

What is the appearance of a Kaposi sarcoma in an AIDS patient?

A

red to purple plaques or nodules that arise on the skin all over the body

39
Q

What is the most common manifestation of AIDS?

A

secondary infection by opportunists- organisms that normally aren’t present with an intact immune system but appear in the absence of T helper cells

40
Q

What bacterial infections are HIV patients more susceptible to?

A

infection by encapsulated organisms from lack of humoral immunity (ex. Strep pneumo)

41
Q

What mycobacterial infections are HIV patients more susceptible to?

A

mycobacterium tuberculosis and mycobacterium avium-intracellulare

42
Q

What fungal infections are HIV patients more susceptible to?

A 
Candida albicans
Cryptococcus neoformans
Histoplasma capsulatum
Coccidioides immitis
Pneumocustis jiroveci pneumonia
43
Q

What viral infections are HIV patients more susceptible to?

A

Herpes zoster- painful vesicles
Epstein-Barr virus- oral hairy leukoplakia (white hairlike projections from tongue)
Herpes Simplex- genital and oral outbreaks
Cytomegalovirus (CMV)- chorioretinitis and blindness

44
Q

What protozoa are HIV patients more susceptible to?

A

Toxoplasma gondii- causes mass lesion in brain

Cryptosporidium, Microsporidia, and Isospora belli- chronic diarrhea

45
Q

How is diagnosis of HIV and AIDS done?

A
  • Viral RNA or antigens can be detected in blood within weeks
  • 3-6 weeks later, antibodies against HIV appear via ELISA
  • Western blot test- light up the antibodies against HIV antigens
  • Rapid testing of blood, plasma, and saliva
46
Q

What clinical presentation occurs in which a physician should suspect HIV/AIDS?

A

when an at-risk individual has constitutional symptoms

*fever, night sweats, generalized adenopathy, recurrent bacterial infections, tuberculosis, skin zoster, or oral thrush

47
Q

What is the CD4+ count when AIDS is diagnosed?

A
48
Q

What are the 3 challenges in developing HIV/AIDS vaccine?

A

rapid mutation of HIV, HIV can transmit from cell to cell, poor animal models

COM MOD 2.2 Viruses (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions