MedCosmos Surgery
Surgery Lecture Notes, Books, MCQ and Good Articles
Friday, September 5, 2008
Transplantation MCQ
1. The “father of experimental surgery” who performed pioneering
research, including several transplantation procedures, was:
A. Homer, the Greek who described the Chimaera in his Iliad.
B. Gasparo Tagliacozzi, the Italian who described a method of
reconstructing the nose.
C. John Hunter, the Scot who performed autografts and xenografts.
D. Emrick Ullmann, the Austrian who performed the first successful
renal allograft.
E. Alexis Carrel, the Franco-American who described a successful
technique for vascular anastomosis.
Answer: C
DISCUSSION: All of the descriptions are correct and represent
important contributions to the history of transplantation. However,
the Scottish surgeon John Hunter (1728–1793), is rightfully known as
the father of experimental surgery because of his pioneering
research. Several of his experimental procedures involved
transplantation, including autografting of a cock's spur to its comb
and xenografting of a human tooth to the comb of a cock.
2. Transplantation terminology contains terms to describe the
relationship of the graft donor to the graft recipient. Historical terms
such as “homograft” and “heterograft” have been replaced by less
ambiguous terms. The correct modern terminology for a graft
between genetically nonidentical members of the same species is:
A. Allogeneic graft.
B. Autogeneic graft.
C. Isogeneic graft.
D. Syngeneic graft.
E. Xenogeneic graft.
Answer: A
,3. The modern era of clinical organ transplantation began with the
advent of chemical immunosuppression. The important drug
discovery that produced the initial success of cadaveric
transplantation was:
A. Cyclophosphamide.
B. Azathioprine.
C. Cyclosporine.
D. Antilymphocyte serum.
E. Monoclonal antibody OKT3.
Answer: B
DISCUSSION: All of the listed drugs have immunosuppressive activity
that has proved useful in transplant recipients. However, the
discovery in 1959 by Schwartz and Dameshek that 6-mercaptopurine
blocked antibody production and the subsequent creation by
Hitchings in 1961 of its safe, convenient imidazole derivative named
azathioprine produced the first consistently effective
immunosuppression for successful cadaveric renal transplantation.
4. Which of the following statements correctly characterize the genetic
basis of histocompatibility?
A. Histocompatibility is determined by a series of genes inherited as a
complex and subject to the mendelian rules that characterize
recessive traits.
B. Histocompatibility depends in part on the inheritance of
histocompatibility genes and in part on the inheritance of T-cell
receptor genes.
C. Major histocompatibility genes are polymorphic.
D. Histocompatibility genes are independently segregating and
co-dominant.
E. Histocompatibility is learned.
Answer: CDE
DISCUSSION: Histocompatibility refers to the genetic determinants of
graft rejection. The determinants of overwhelming importance consist
of a series of histocompatibility genes that segregate independently
during meiosis. Each gene has multiple, dominant alleles.
Histocompatibility genes and the proteins they encode are highly
polymorphic (i.e., they exist in multiple forms).
5. The major histocompatibility complex (MHC) includes genes that
encode which of the following proteins?
A. HLA-A.
B. HLA-DR.
C. TAP-1.
,D. 21-Hydroxylase.
E. HLA-L.
Answer: ABCD
DISCUSSION: The major histocompatibility complex (MHC) includes
genes encoding histocompatibility antigens, some other proteins, and
a number of pseudogenes that do not encode proteins. The class I
region encodes more than 15 genes, including the classical transplant
genes A, B, and C as well as HLA-E, F, and G and four pseudogenes, H,
J, K, and L. The class II region contains more than 25 genes, including
those for the transplantation antigens HLA-DR, DQ, and DP. The
region also includes two alpha genes, DMA and DNA, and two beta
genes, DMB and DOB, genes for the low-molecular-weight proteins
(LMPs) LMP2 and LMP3 and for the transporter molecules TAP1 and
TAP2. The class III region, lying between class II and class I, contains
more than 30 genes, among which are the genes encoding the
complement components factor B, C2, and both C4 molecules, both
tumor necrosis factor genes alpha and beta, and the heat shock
proteins Hsp 1H and Hsp 70 2, and 21-hydroxylase.
6. Which of the following distinguish MHC class I from MHC class II
antigens?
A. MHC class I and class II antigens are encoded in different regions of
the MHC complex.
B. MHC class I antigens are expressed on specialized antigen-
presenting cells, whereas MHC class II antigens are expressed on all
cells.
C. MHC class I and class II are members of different supergene
families.
D. MHC class I are considered to be the major histocompatibility
antigens and MHC class II the minor histocompatibility antigens.
E. MHC class I is recognized by the CD8 glycoprotein, whereas MHC
class II is recognized by the CD4 glycoprotein.
Answer: AE
DISCUSSION: MHC class I and class II antigens are encoded by genes
in different regions of the MHC. The genes and the proteins they
encode are homologous to immunoglobulins and thus are members
of the immunoglobulin supergene family. MHC class I antigens are
expressed on the surface of all cells, whereas MHC class II antigens
are largely restricted in expression to antigen-presenting cells and
endothelial cells. Both MHC class I and class II antigens are major
histocompatibility antigens because their incompatibility in the donor
and recipient can lead to very rapid and vigorous rejection of an
allograft. The T cells that have antigen receptors specific for MHC class
I plus peptide express CD8, a co-receptor that binds to the MHC class I
, molecules. The T cells that have antigen preceptors specific for MHC
class II plus peptide express CD4, a co-receptor that binds to MHC
class II molecules.
7. Which of the following characterize the role of the major
histocompatibility antigens in immune responses?
A. The major histocompatibility antigens are critical in antigen
processing and presentation.
B. Major histocompatibility antigens contribute to the maturation of T
cells in the thymus.
C. T cells recognize only foreign antigens that are complexed with
major histocompatibility antigens.
D. Expression of major histocompatibility antigens is increased in
inflammation.
E. Recognition of major histocompatibility antigens is critical to the
development of tolerance.
Answer: ABCDE
DISCUSSION: Once thought to be solely markers of individuality, MHC
antigens are crucial to cell-mediated immune responses. Foreign
antigens taken up by antigen-presenting cells are degraded and then
become complexed with MHC molecules and expressed on the cell
surface, and these events are enhanced in inflammation. Since T cells
recognize only foreign antigens expressed as peptides in association
with MHC antigens, the possibility for recognition is increased as a
consequence of inflammation. Since T cells recognize only antigens
expressed in association with MHC antigens, recognition of these
antigens is critical to the development of tolerance to “self.”
8. The unusual intensity of alloimmune responses reflects which of
the following characteristics?
A. The presence of a peptide-binding groove in the MHC molecule.
B. Recognition of the native structure of allogeneic MHC molecules.
C. The high frequency of T cells able to recognize directly allogeneic
MHC antigens.
D. Stimulation of many T-cell receptors during the interaction of a T
cell with an antigen-presenting cell.
E. The high frequency of antigen-presenting cells able to be
recognized by T cells.
Answer: BCDE
DISCUSSION: Allotransplantation evokes an unusually intense and
rapid cellular immune response. In contrast to conventional cellular
immune responses, in which foreign antigens are recognized only as
peptides in the groove of self MHC antigens, allogeneic MHC antigens
Surgery Lecture Notes, Books, MCQ and Good Articles
Friday, September 5, 2008
Transplantation MCQ
1. The “father of experimental surgery” who performed pioneering
research, including several transplantation procedures, was:
A. Homer, the Greek who described the Chimaera in his Iliad.
B. Gasparo Tagliacozzi, the Italian who described a method of
reconstructing the nose.
C. John Hunter, the Scot who performed autografts and xenografts.
D. Emrick Ullmann, the Austrian who performed the first successful
renal allograft.
E. Alexis Carrel, the Franco-American who described a successful
technique for vascular anastomosis.
Answer: C
DISCUSSION: All of the descriptions are correct and represent
important contributions to the history of transplantation. However,
the Scottish surgeon John Hunter (1728–1793), is rightfully known as
the father of experimental surgery because of his pioneering
research. Several of his experimental procedures involved
transplantation, including autografting of a cock's spur to its comb
and xenografting of a human tooth to the comb of a cock.
2. Transplantation terminology contains terms to describe the
relationship of the graft donor to the graft recipient. Historical terms
such as “homograft” and “heterograft” have been replaced by less
ambiguous terms. The correct modern terminology for a graft
between genetically nonidentical members of the same species is:
A. Allogeneic graft.
B. Autogeneic graft.
C. Isogeneic graft.
D. Syngeneic graft.
E. Xenogeneic graft.
Answer: A
,3. The modern era of clinical organ transplantation began with the
advent of chemical immunosuppression. The important drug
discovery that produced the initial success of cadaveric
transplantation was:
A. Cyclophosphamide.
B. Azathioprine.
C. Cyclosporine.
D. Antilymphocyte serum.
E. Monoclonal antibody OKT3.
Answer: B
DISCUSSION: All of the listed drugs have immunosuppressive activity
that has proved useful in transplant recipients. However, the
discovery in 1959 by Schwartz and Dameshek that 6-mercaptopurine
blocked antibody production and the subsequent creation by
Hitchings in 1961 of its safe, convenient imidazole derivative named
azathioprine produced the first consistently effective
immunosuppression for successful cadaveric renal transplantation.
4. Which of the following statements correctly characterize the genetic
basis of histocompatibility?
A. Histocompatibility is determined by a series of genes inherited as a
complex and subject to the mendelian rules that characterize
recessive traits.
B. Histocompatibility depends in part on the inheritance of
histocompatibility genes and in part on the inheritance of T-cell
receptor genes.
C. Major histocompatibility genes are polymorphic.
D. Histocompatibility genes are independently segregating and
co-dominant.
E. Histocompatibility is learned.
Answer: CDE
DISCUSSION: Histocompatibility refers to the genetic determinants of
graft rejection. The determinants of overwhelming importance consist
of a series of histocompatibility genes that segregate independently
during meiosis. Each gene has multiple, dominant alleles.
Histocompatibility genes and the proteins they encode are highly
polymorphic (i.e., they exist in multiple forms).
5. The major histocompatibility complex (MHC) includes genes that
encode which of the following proteins?
A. HLA-A.
B. HLA-DR.
C. TAP-1.
,D. 21-Hydroxylase.
E. HLA-L.
Answer: ABCD
DISCUSSION: The major histocompatibility complex (MHC) includes
genes encoding histocompatibility antigens, some other proteins, and
a number of pseudogenes that do not encode proteins. The class I
region encodes more than 15 genes, including the classical transplant
genes A, B, and C as well as HLA-E, F, and G and four pseudogenes, H,
J, K, and L. The class II region contains more than 25 genes, including
those for the transplantation antigens HLA-DR, DQ, and DP. The
region also includes two alpha genes, DMA and DNA, and two beta
genes, DMB and DOB, genes for the low-molecular-weight proteins
(LMPs) LMP2 and LMP3 and for the transporter molecules TAP1 and
TAP2. The class III region, lying between class II and class I, contains
more than 30 genes, among which are the genes encoding the
complement components factor B, C2, and both C4 molecules, both
tumor necrosis factor genes alpha and beta, and the heat shock
proteins Hsp 1H and Hsp 70 2, and 21-hydroxylase.
6. Which of the following distinguish MHC class I from MHC class II
antigens?
A. MHC class I and class II antigens are encoded in different regions of
the MHC complex.
B. MHC class I antigens are expressed on specialized antigen-
presenting cells, whereas MHC class II antigens are expressed on all
cells.
C. MHC class I and class II are members of different supergene
families.
D. MHC class I are considered to be the major histocompatibility
antigens and MHC class II the minor histocompatibility antigens.
E. MHC class I is recognized by the CD8 glycoprotein, whereas MHC
class II is recognized by the CD4 glycoprotein.
Answer: AE
DISCUSSION: MHC class I and class II antigens are encoded by genes
in different regions of the MHC. The genes and the proteins they
encode are homologous to immunoglobulins and thus are members
of the immunoglobulin supergene family. MHC class I antigens are
expressed on the surface of all cells, whereas MHC class II antigens
are largely restricted in expression to antigen-presenting cells and
endothelial cells. Both MHC class I and class II antigens are major
histocompatibility antigens because their incompatibility in the donor
and recipient can lead to very rapid and vigorous rejection of an
allograft. The T cells that have antigen receptors specific for MHC class
I plus peptide express CD8, a co-receptor that binds to the MHC class I
, molecules. The T cells that have antigen preceptors specific for MHC
class II plus peptide express CD4, a co-receptor that binds to MHC
class II molecules.
7. Which of the following characterize the role of the major
histocompatibility antigens in immune responses?
A. The major histocompatibility antigens are critical in antigen
processing and presentation.
B. Major histocompatibility antigens contribute to the maturation of T
cells in the thymus.
C. T cells recognize only foreign antigens that are complexed with
major histocompatibility antigens.
D. Expression of major histocompatibility antigens is increased in
inflammation.
E. Recognition of major histocompatibility antigens is critical to the
development of tolerance.
Answer: ABCDE
DISCUSSION: Once thought to be solely markers of individuality, MHC
antigens are crucial to cell-mediated immune responses. Foreign
antigens taken up by antigen-presenting cells are degraded and then
become complexed with MHC molecules and expressed on the cell
surface, and these events are enhanced in inflammation. Since T cells
recognize only foreign antigens expressed as peptides in association
with MHC antigens, the possibility for recognition is increased as a
consequence of inflammation. Since T cells recognize only antigens
expressed in association with MHC antigens, recognition of these
antigens is critical to the development of tolerance to “self.”
8. The unusual intensity of alloimmune responses reflects which of
the following characteristics?
A. The presence of a peptide-binding groove in the MHC molecule.
B. Recognition of the native structure of allogeneic MHC molecules.
C. The high frequency of T cells able to recognize directly allogeneic
MHC antigens.
D. Stimulation of many T-cell receptors during the interaction of a T
cell with an antigen-presenting cell.
E. The high frequency of antigen-presenting cells able to be
recognized by T cells.
Answer: BCDE
DISCUSSION: Allotransplantation evokes an unusually intense and
rapid cellular immune response. In contrast to conventional cellular
immune responses, in which foreign antigens are recognized only as
peptides in the groove of self MHC antigens, allogeneic MHC antigens
