MDS PREP
The chemical nature of bacterial exotoxins is, a
1. low molecular weight polypeptide
2. lipopolysaccharide complex
3. protein
4. complex carbohydrate
Microbiology
Answer: 2
The chemical nature of bacterial exotoxins is, a
lipopolysaccharide complex
What is the effect of Actinomycin D on orthomyxoviruses?
1) Stimulates multiplication
2) Inhibits multiplication
3) No effect
4) Enhances stability
General Microbiology Answer: 2Actinomycin D is an antibiotic that inhibits RNA synthesis. In the case of orthomyxoviruses, it effectively inhibits their multiplication by preventing the transcription of viral RNA, thereby blocking the virus ability to replicate. Actinomycin D inhibits the multiplication of orthomyxoviruses by blocking RNA synthesis, which is crucial for viral replication.
What is the purpose of using aluminum hydroxide as an adjuvant in the hepatitis B vaccine?
1) To increase the immunogenicity of the vaccine
2) To prevent bacterial contamination
3) To enhance the stability of the vaccine
4) To reduce the amount of antigen needed for immunization
General Microbiology Answer: 1
Aluminum hydroxide is used as an adjuvant in the hepatitis B vaccine to increase the immunogenicity of the vaccine, enhancing the body's immune response to the antigen.
What type of antibodies are known as "coproantibodies"?
1) IgA
2) IgM
3) IgG
4) Antibodies found in feces
General Microbiology Answer: 4Copro antibodies are antibodies found in feces These are typically IgA antibodies that are produced in response to infections in the gastrointestinal tract, including typhoid fever. They can be detected in stool samples and are used in diagnostic tests.
The period from disease initiation to disease detection in non-infectious disease is called -
1. Incubation period
2. Serial interval
3. Latent period
4. Lag time
Microbiology
Answer: 3
Incubation period: This term is typically used for
infectious diseases and refers to the time between exposure to the
infectious agent and the onset of symptoms.
Serial interval: This refers to the time between
successive cases in a chain of transmission, specifically in infectious
diseases.
Latent period: This is the time from the initiation of
the disease process (or exposure to a risk factor) until the disease is
detectable or until symptoms appear. In non-infectious diseases, this period
can be significant, as the disease may be developing without any noticeable
symptoms.
Lag time: This term can refer to various delays in
processes but is not specifically defined in the context of disease
initiation and detection.
What is the commonest subtype of Hepatitis B virus in Thailand?
1) Subtype A
2) Subtype B
3) Subtype C
4) Subtype E
General Microbiology Answer: 4
Subtype B is the most common subtype of Hepatitis B virus found in Thailand, linked to increased risks of chronic infection.
Which of the following is the correct Lancefield group for Streptococcus pyogenes?
1) A
2) B
3) C
4) D
Streptococcus pyogenes is classified as Lancefield group A.
What is the significance of HLA class I antigens in the context of graft rejection and cell mediated cytolysis?
1) They are only involved in cell-to-cell recognition in the immune system.
2) They are the principal antigens that induce an immune response in the host against transplanted tissues.
3) They have no role in graft rejection or cell-mediated immunity.
4) They are only involved in the innate immune response.
General Microbiology Answer: 2
HLA class I antigens are the principal antigens that induce an immune response in the host against transplanted tissues.