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  #1  
Old 05-19-2014
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Question Embryo Question for Today

A 3-month-old boy who was born at full term
presents to the pediatrician for evaluation of
his congenital heart condition. His 39-year-old
mother is healthy. She states that the pregnancy
was notable for a decreased level of
α−fetoprotein. The boy has fl at facies, prominent
epicanthal folds, and a simian crease on
each hand. This child most likely has a heart
condition that involves tissue derived from
which of the following structures?

(A) Bulbus cordis
(B) Neural crest cells
(C) Primitive atrium
(D) Primitive ventricle
(E) Truncus arteriosus

what do you think guys??
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Old 05-19-2014
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Quote:
Originally Posted by drpisho View Post
A 3-month-old boy who was born at full term
presents to the pediatrician for evaluation of
his congenital heart condition. His 39-year-old
mother is healthy. She states that the pregnancy
was notable for a decreased level of
α−fetoprotein. The boy has fl at facies, prominent
epicanthal folds, and a simian crease on
each hand. This child most likely has a heart
condition that involves tissue derived from
which of the following structures?

(A) Bulbus cordis
(B) Neural crest cells
(C) Primitive atrium
(D) Primitive ventricle
(E) Truncus arteriosus

what do you think guys??
pt has down syndrome, ASD VSD are main heart probs, i am torn between C and D.
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Old 05-19-2014
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Most common cardiac anomaly is VSD

Which is a defect in the membranous part of the interventricular septum which is derived frim neural crest cells

So i think the answer is B
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  #4  
Old 05-19-2014
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B. Neural crest cells

Endocardial cushion defects are seen in Downs..........

Endocardial cushions are derived from neural crest cells.
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  #5  
Old 05-20-2014
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Correct Answer

Quote:
Originally Posted by medstud. View Post
B. Neural crest cells

Endocardial cushion defects are seen in Downs..........

Endocardial cushions are derived from neural crest cells.
exactly guys, i thought exactly the same way, but here is the answer:

The correct answer is C. Based on the physical
findings and the low α-fetoprotein during
pregnancy, this child most likely has Down’s
syndrome caused by trisomy 21. Down’s syndrome
is associated with many defects of embryology;
the most common cardiac abnormality
is an atrial septal defect of the septum
primum, present in 45% of patients. The atrial
septum develops as an outgrowth of the wall of
the primitive atrium. The primitive atrium also
develops into the trabeculated part of both
atria. The second most common heart defect
in children with Down’s syndrome is ventricular
septal defect, appearing in 35% of patients.

this is from First Aid Q and A and im thinking 2 things:
1.either they got it wrong or 2. their way of "tricking" you was to ask you from what structure is the atrial septum derived... cause it is true that it comes from the primitive atria, however the primitive atria was developed via endocardial cushions which are neural crest cells that have migrated.

ALSO. after this i did some research so to ADD:
#1 MC cardiac defect in Downs: Ostium Primum ASD
#2 MC cardiac defect in Downs: VSD
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  #6  
Old 05-20-2014
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hi guys!Just remember the neural crest defect 3 thinks :
1.Transposition of great vessels
2.Tetralogy of Fallot
3.Persistent truncus arteriosus





FA2014 p.263
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  #7  
Old 05-25-2014
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Vsd - most common heart anomaly and it is most commonly associated with fetal alcohol syndrome
Asd-secundum(90% cases) and primum(10%cases) primus defect is associated with down syndrome...
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