Infection And Disease

Front 1

The autoimmune disease most closely associated with anti-nuclear antibodies is:

a) Systemic lupus erythematosus

b) Myasthenia gravis

c) Type 1 Diabetes

d) Hashimoto's disease

e) Rheumatoid arthritis

Back 1

a) Systemic lupus erythematosus

Front 2

Wiskott-Aldrich syndrome is best described as being a disease associated with:

a) Non-organ specific autoimmunity

b) Organ-specific autoimmunity

c) Type 1 hypersensitivity

d) Secondary immunodeficiency

e) Primary immunodeficiency

Back 2

e) Primary immunodeficiency

(Secondary immunodeficiencies are caused by external agents, such as the HIV virus for AIDS)

Front 3

Mutations in which gene are most commonly associated with SCID?

a) RAG-1

b) ADA

c) RAG-2

d) JAK-3

e) Gamma-c

Back 3

e) Gamma-c

Front 4

The molecule most closely associated with killing of target cells by cytotoxic T lymphocytes is:

a) Membrane attack complex (MAC)

b) CD8

c) Granzyme B

d) TCR

e) MHC Class I

Back 4

c) Granzyme B

Although most cytotoxic T-cells are CD8+ and therefore recognise peptides presented by MHC class I molecules, this is not the single best answer

Front 5

Cell-mediated immunity is a term most often used when describing responses involving:

a) Eosinophils

b) Neutrophils

c) T cells

d) B cells

E) NK cells

Back 5

c) T cells

Front 6

The part of an IgG antibody that binds complement component C1q is best described as the:

a) complement receptor

b) Heavy chain

c) constant region

d) c-gamma domain

e) Fc

Back 6

e) Fc

The Fc part of IgG comprises the C1q-binding C g 2 domain together with the Cg3 domain.

Front 7

Type 1 Hypersensitivity is most closely associated with:

a) Il-4

b) Leukocytes

c) Antibodies

d) Mast cells

e) Il-5

Back 7

d) Mast cells

Front 8

HLA-B27 is best described as being a :

a) MHC class I molecule

b) Hetrodimer

c) Glycoprotein

d) HLA class I molecule

e) peptide binding molecule

Back 8

d) HLA class I molecule

Front 9

The cell type most closely associated with chronic inflammation is the:

a) NK cell

b) Mast cell

c) B cell

d) Basophil

e) Macrophage

Back 9

Macrophage

Front 10

Which one of the following statements about English law is correct?

a) All cases of all infectious diseases must be reported to the authorities?

b) A patient with TB can be detained in hospital without their consent

c) Civil cases are decided out of court and only criminal cases are decided within the court system

d) The public heath (control of infectious diseases) act is an example of common law

e) Judges can decide to disregard statutes and make a common sense judgement

Back 10

a) A patient with TB can be detained in hospital without their consent

Front 11

Following a routine, non complicated, surgical procedure scar formation is usually the result of:

a) early mobility

b) Infection

c) Wound dehiscence

d) Healing by secondary intention

e) Basement membrane disruption as part of surgery

Back 11

e) Basement membrane disruption as part of surgery

Front 12

Lazarus' Transactional Model of Stress states that:

a) Stress puts people at risk of becoming ill

b) Stress occurs when the perceived demands of the environment exceed the individual's perceived capacity to cope

c) Stress in small amounts can promote physical and psychological well-being

d) Stress occurs when the demands of the environment exceed the individual's capacity to cope

e) Both positive and negative life events can cause stress

Back 12

Stress occurs when the perceived demands of the environment exceed the individual's perceived capacity to cope

Front 13

Negative staining using India ink is used with a light microscope to visualise:

a) Flagella

b) Capsules

c) Spirochaetes

d) Endospores

e) Pilli/fimbriae

Back 13

b) Capsules

Front 14

Aspergillus species are important in medicine because they:

A. Are thermophiles that can survive being at 55ºc

B. Can invade lungs and blood vessals in immunocompromised people

C. Are ubiquitous environmental fungi

D. Grow as filaments in a mycelium

E. Produce asexual spores known as conidia

Back 14

b) can invade lungs and blood vessals in immunocompromised people

Front 15

The most important characteristic of Entamoeba histolytica is that it:

A. Can cause severe dysentery

B. Can cause mild or asymptomatic diarrhoea

C. May be acquired via anal sexual activity

D. Produces cysts which survive in the environment

E. Is common in subtropical and tropical countries

Back 15

a) can cause severe dysentery

(dysentery = infection of the intestines resulting in severe diarrhoea with the presence of blood and mucus in the faeces).

Front 16

Which one of the following statements is correct?

Select one:

A. If you know the proportion of a population that has a disease, the prevalence can be calculated

B. Molecular epidemiology is appropriate for studying viral but not bacterial infections

C. Seroepidemiology requires serum samples rather than plasma samples

D. The number of cases of a viral disease per 100,000 people is referred to as the incidence

E. Epidemiology is exclusively the study of epidemics

Back 16

The correct answer is: If you know the proportion of a population that has a disease, the prevalence can be calculated

Front 17

Which one of the following statements is correct?

Select one:

A. Enveloped viruses are generally resistant to chloroform

B. Icosahedral capsids possess twenty faces and twelve vertices

C. HBV, retroviruses and picornaviruses are the only types of virus to contain reverse transcriptase

D. Prions contain either DNA or RNA but never both

E. Adenovirus particles exhibit helical symmetry

Back 17

Icosahedral capsids possess 20 faces and 12 vertices

Front 18

Pattern recognition receptors (PRR) include which of the following?

A Lipopolysaccharide (LPS)

B Pathogen-associated molecular patterns (PAMPs)

C Lipoteichoic acid

D Lectin-like molecules

E Unmethylated CpG sequences

Back 18

The correct answer is D. Many PRR are lectin-like in that they recognize exposed microbial sugars. Gram-negative bacteria produce LPS, the biologically active lipid A moiety of which is recognized by LPS-binding protein (LBP); the LBP-LPS complex is captured by the CD14 scavenger molecule on phagocytic cells which then become activated through Toll-like receptor-4 (TLR4). PAMPs are recognized by the pattern recognition receptors. Lipoteichoic acid is produced by Gram-positive bacteria and acts as a PAMP. Unmethylated guanosine-cytosine dinucleotide sequences in bacterial DNA are an example of a PAMP linked to intracellular infection.

Front 19

A polymorphonuclear neutrophil (PMN):

A Is a bone marrow stem cell

B Is closely similar to a mast cell

C Contains microbicidal cytoplasmic granule

sD Is not a professional phagocytic cell

E Has granules that stain with eosin

Back 19

The correct answer is C. The granules contain a wide spectrum of microbicidal agents. The bone marrow hematopoietic stem cell is the precursor of the formed elements of the blood which include the PMN. The granular polymorphonuclear cell which stains with basic dyes (i.e., the basophil) is similar to a mast cell. The major professional phagocytic cells are the neutrophils and the macrophages. The word neutrophil implies that the granules stain neither with acid nor basic dyes. The eosinophil has granules that stain with the acid dye eosin and is important in defense against parasitic infections.

Front 20

Which of the following is NOT produced following activation of the NADPH oxidase microbicidal pathway?

A O2−

B O2

C H2O2

D NO

E OH

Back 20

The correct answer is D. NO is produced following the induction of nitric oxide synthase. O2− is the superoxide anion obtained by addition of an electron to molecular oxygen by the cytochrome b558oxidase system. Oxygen is utilized as a substrate to which cytochrome b558 transfers an electron from NADPH. Hydrogen peroxide is generated from O2− and, although not as active as the free radicals, is more stable and therefore diffuses further. The hydroxyl radical is one of the most reactive free radicals known and is formed by the reduction of H2O2, for example following its reaction with Fe2+.

Front 21

Which of the following statements is TRUE of interferons?

A Interferons are found only in mammalian species

B Interferons are divided into five main families

C Interferons induce enzyme synthesis in the target cell

D Interferons only affect infected cells

E Interferons are specific for individual viruses

Back 21

The correct answer is C. Derepression of genes in the target cell result in the synthesis of a protein kinase and an endonuclease. Interferons are present in birds, reptiles, and fishes as well as higher animals. There are three main families of interferons: α, β, and γ. In fact, the interferons render cells unable to support viral replication, thereby establishing a cordon sanitaire around the site of a virus infection so restraining its spread. Interferons were first recognized by the phenomenon of viral interference in which an animal infected with one virus resists superinfection by a second unrelated virus.

Front 22

Natural killer (NK) cells do NOT:

A Respond to interferon

B Contain perforin

C Contain tumor necrosis factor (TNF)

D Kill only by damaging the target cell outer membrane

E Contain serine proteases

Back 22

The correct answer is D. Perforin inserts into the target cell membrane thereby facilitating entry of TNF and granzymes into the target cell. Their activity is stimulated by interferon. They contain perforin, which is released on contact with a target, inserts itself into the target cell membrane, and creates a pore through which granzymes are transferred into the target cell. TNF produced by NK cells contributes to the killer function. NK cells contain a number of serine proteases of the granzyme family, one of which, granzyme B, can split procaspase 8 and thereby activate apoptosis in the target cell.

Front 23

Of the following, which is the way in which toxoplasma is spread?

1) Insect vectors

2) Milk

3) Transplacental

4) Aerosol droplets

5) Direct person-to-person contact

Back 23

= Transplacental

Front 24

The best description relating to emerging infections and disease is that:

1) Influenza virus H5N1 is the result of genetic reassortment between pig & human influenza viruses

2) Emergence requires infection and transmission

3) Influenza pandemics occur because of antigenic drift

4) Legionnaire’s disease is transmitted by ticks5) Most emerging infections are drug resistantQ4 The antiviral agent aciclovir (ACV) is best descr

Back 24

=Emergence requires infection and transmission

Front 25

The single best example of a strategy used by microbes to avoid the immunesystem is:

1) The intracellular habitat of staphylococcus

2) Antigenic shift by influenza

3) Binding of IgA by staphylococcal protein

4) Enhancement of MHC expression

5) Killing of CD8+ cells by HIV

Back 25

Antigenic shift by influenza

Front 26

Immunological tolerance can result from:

1) Positive selection of T-cells in the thymus

2) T-cell activation

3) Activity of FoxP3+T-cells

4) Apoptosis of eosinophils

5) Secretion of IL-2 and TNF

Back 26

Activity of FoxP3+ T-cells

Front 27

The single best description of the innate immune response is:

1) Innate immune responses do not adapt

2) Innate immune responses are exclusively mediated by phagocytic cells

3) The genetic code for innate immune receptors does not vary between people.

4) Toll-like receptor 4 can recognise a variety of different bacterial pathogens

5) Innate immune receptors only recognise non-self molecules

Back 27

= Toll like receptor 4 can recognise a variety of different bacterial pathogens

(1 is incorrect becauseUpregulationof TLR receptors occurs.)

Front 28

Which of the following is the single best example of a virus that can be transmittedvia contaminated drinking water?:

1) Hepatitis A

2) Hepatitis B

3) Herpes simplex virus

4) Human immunodeficiency virus

5) Papillomavirus

Back 28

=1) Hepatitis A

Front 29

Which one of the following diseases is the best example of a zoonosis caused by anarbovirus?:1) Dengue

2) Yellow fever

3) Rabies

4) Tick borne encephalitis

5) Human immunodeficiency virus

Back 29

Denguetransmits human to human. Is not a zoonosis. Yellowfever can be a zoonosis if it is jungle yellow fever. In a town, urban yellowfever exists, which can be a zoonosis but at the same time can also not be azoonosis.Rabies isnot transmitted by mosquitos, transmitted by dogs. So not a zoonosistransmitted by a arbovirus, is a zoonosis transmitted by an animal.

= Tick borne encephalitis

Front 30

Which of the following viruses can establish latency by integrating into the hostgenome?:

1) Varicella-zoster virus

2) Cytomegalovirus

3) Influenza virus

4) Human immunodeficiency virus

5) Respiratory syncytial virus

Back 30

= human immunodeficiency virus