Multiple Choice Question Test - XII (Basic Periodontology).

This is a self assessment test consisting of ten questions. Click evaluate to get result.

1. Most leukotoxic strains of A. actinomycetemcomitans are of,

Aggregatibacter actinomycetemcomitans has six recognized serotypes a-f, which are classified into 3 major phylogenetic lineages: (i) serotype b, (ii) serotype c, and (iii) serotype a, d, e and f. Serotype b is found to contain the highly leukotoxic strains and is most commonly seen in patients with localized juvenile periodontitis. Recently serotype g has been identified.

Reference: Brian Henderson, John M. Ward, and Derren Ready; Aggregatibacter (Actinobacillus) actinomycetemcomitans: a triple A* periodontopathogen?; Periodontology 2000; 54(1): 78-105; 2010. 

Serotype a.
Serotype b.
Serotype c.
Serotype d.
Correct Answer - option 2

2. Decay-accelerating factor is present on,

Decay-accelerating factor recognizes C4b and C3b fragments that condense with cell-surface hydroxyl or amino groups when nascent C4b and C3b are locally generated during C4 and c3 activation. Interaction of daf with cell-associated C4b and C3b polypeptides interferes with their ability to catalyze the conversion of C2 and factor B to enzymatically active C2a and Bb and thereby prevents the formation of C4b2a and C3bBb, the amplification convertases of the complement cascade. It is present on all leukocytes, erythrocytes and platelets.

Reference: Medof ME, Walter EI, Rutgers JL, Knowles DM, Nussenzweig V: Identification of the complement decay-accelerating factor (DAF) on epithelium and glandular cells and in body fluids. J Exp Med 1987, 165:848 – 864.

All leukocytes.
All of above.
Correct Answer - option 4

3. Class II MHC molecules have,

In humans, the MHC complex consists of more than 200 genes located close together on chromosome 6. Genes in this complex are categorized into three basic groups: class I, class II, and class III. Class II MHC molecules are composed of two polypeptide chains an α and a β chain of approximately equal length and both chains have four regions:

  • First is the cytoplasmic region which contains sites for phosphoylation and binding to cytoskeletal elements
  • The transmembrane region contains hydrophic amino acids by which the molecule is anchored in the cell membrane
  • A highly conserved α2 domain and a highly conserved β2 domain to which CD4 binds
  • A highly polymorphic peptide binding region formed from the α1 and β1 domains
A long α chain and a short β chain,
A long β chain and a short α chain.
Identical and non-covalently associated polypeptide chains.
Non-identical and non-covalently associated polypeptide chains.
Correct Answer - option 4

4. Half life of C reactive protein (CRP) is,

C reactive protein (CRP) is termed `acute-phase` because the time-course of the rise above normal levels is rapid within 6 hours, peaking at about 48 hours. The half-life of CRP is about 19 hours and relatively constant, so that levels fall sharply after initiation unless the plasma level is maintained high by continued CRP production in response to continued antigen exposure and inflammation. It therefore represents a good marker for disease activity, and to some degree, severity. However, although it is not specific for a single disease process, CRP can be utilised as a tool for monitoring immune activity in patients with a particular disease. In most situations, the factors controlling CRP release and regulation are essentially those controlling inflammation or tissue injury. It is therefore relatively tightly regulated depending on the presence and degree of inflammation, with typical rises and falls in plasma CRP levels, forming a characteristic homeostatic, oscillatory cycle when inflammation occurs.

Reference: Brendon J Coventry et al. CRP identifies homeostatic immune oscillations in cancer patients: a potential treatment targeting tool? Journal of Translational Medicine 2009, 7:102

10 hours.
15 hours.
19 hours.
24 hours.
Correct Answer - option 3

5. Depending upon the duration of drug release, the local drug delivery agents are considered,

The difference between controlled release and sustained release is that controlled release is a perfectly zero order release; that is, the drug releases over time irrespective of concentration. Sustained release implies slow release of the drug over a time period. It may or may not be controlled release.

Sustained release if the duration of drug release is more than 24 hours.
Sustained release if the duration of drug release is less than 24 hours.
Controlled release if the duration of drug release is less than 24 hours.
All of above.
Correct Answer - option 2

6. In latent phase of infection Epstein-Barr virus resides in,

Epstein-Barr virus (EBV) causes in humans infectious  mononucleosis  as  a  "primary"  disease. Burkitt`s  Lymphoma  and  Nasopharyngeal Carcinoma may be considered as "secondary" diseases developing only in persons with long preceeding EBV infection. Following the primary infection with EBV, virus  can  be  isolated  from  the salivary  duct  and from throat swabs for months  or years, and  B-Iymphocytes are lifelong carriers of EBV genomes and can be used to establish lymphoblastoid cell lines.

Reference: H. Wolf, E. Wilmes and G. J. Bayliss. Epstein-Barr Virus: Its Site of Persistence and Its Role in the Development of Carcinomas. Haematology and Blood Transfusion  Vol. 26, 191-196.

Sensory nerve ganglia and monocytes.
B-lymphoctes and salivary glands.
Both of above.
None of above.
Correct Answer - option 2

7. Which of the following is not accurate about Cathepsin G,

Cathepsin G is a neutral serine protease that is expressed and synthesized at the promyelocyte stage of development and is packaged in the azurophil (primary) granules. It has important role at the site of inflammation.

It is a member of Granzyme B family.
It is a serine protease.
It is stored in specific granules of neutrophils.
Cathepsin G promotes E-cadherin/protein kinase D1 (PKD1) complex formation.
Correct Answer - option 3

8. In P.Gingivalis, fimbrillin is encoded by,

Fimbriae (the oligomeric form of fimbrillin) are considered important in the adherence and colonization of Porphyromonas gingivalis in the oral cavity. Fimbrillin is the major subunit protein of fimbriae from this human periodontal pathogen. The fimbrillin is encoded by fimA  gene.

Reference: Hua Xie et al. Regulation of the Porphyromonas gingivalis fimA (Fimbrillin) Gene. Infect Immun. 2000 December; 68(12): 6574–6579.

fimA gene.
fimB gene.
fimC gene.
fimD gene.
Correct Answer - option 1

9. Osteopontin and bone sialo protein have an RGD sequence that recognizes,

Osteopontin and bone sialoprotein, originally characterized as bone sialoproteins I and II. Both proteins also have an RGD sequence that recognizes the vitronectin receptor αvβ3 through which these proteins can mediate cell attachment and activate cell signaling pathways.

Reference: Jaro Sodek & Marc D.Mckee.Molecular and cellular biology of alveolar bone. Periodontology 2000, Vol. 24, 2000, 99–126.

Vitronectin receptor αvβ5.
Vitronectin receptor α2β1.
Vitronectin receptor αvβ3.
All of above.
Correct Answer - option 3

10. Concentration of doxycycline in GCF as compared to serum is,

Tetracyclines, particularly doxycycline , tend to be highly concentrated in the gingival crevicular fluid at levels 5–10 times greater than those found in serum and these antibiotics show substantivity because they bind to the tooth structure and are slowly released as still-active agents.

Reference: Pascale D, Gordon J, Lamster I, Mann P, Seiger M, Arndt W. Concentration of doxycycline in human gingival fluid. J Clin Periodontol 1986: 13: 841–844.

2-4 times greater.
5–10 times greater.
10–15 times greater.
Correct Answer - option 3

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