Embryology of CNS and Spinal Cord (Anencephaly, Spina Bifida) for USMLE Step 1
34.3 هزار بار بازدید -
10 سال پیش
-
This video we will cover
This video we will cover embryology of CNS as well as some of the related pathology and pathophysiology of anencephaly and spinabifida. We will allso look into the development of the spinal cord and the neural crest cells. This is in preparation for USMLE Step 1.
INitially there is three plates. The top plates is the epiblast and below is the hypoblast. Above there is the amniotic cavity and below the primitive yolk sac.
The primitive plate attaches the epiblast with the hypoblast. The primitive streak and node start going down and form the notochord. This forms the trilaminar disk and then it is called ectoderm, mesoderm and endoderm. The notochord begins secreting growth factors which stimulate the ectoderm to start raising up because of the growth factors from notochord. This creates a folded and depression above the notochord. The neural crest cells develop from the top portion. These edges grow towards each other and fuse to form the Neural Tube. Before fusion the neural crest cells went away and formed many other things.
The neural tube forms spinal cord and the notochord forms nucleus polposis. Anterior neural pore doesn't develop then it is called anencephaly which has Increase AFP and AChe. ssociated iwth Low folate and Maternal DM. If posterior notochord is not developed, then you can get Spina Bifida. Anterio 25 and posterio 27th day.
CNS DEVELOPMENT
3 pirmary swellings - prosencephalon, mesencephalon and the rhombencephalon. There are 5 secondary swelling. Prosencephalon becomes telencephalon and diencephalon. Telencephalon becomes cerebrum. Diencephalon becomes third ventricle. Midbrain from mesencephalon. Rhombencephaolon becomes metencephalon and myelincephalon. Mesencephalon becomes PONs and cerebellum. And the myelencephalon becomes medulla.
SPINAL CORD DEVELOPMENT
INitially there is three plates. The top plates is the epiblast and below is the hypoblast. Above there is the amniotic cavity and below the primitive yolk sac.
The primitive plate attaches the epiblast with the hypoblast. The primitive streak and node start going down and form the notochord. This forms the trilaminar disk and then it is called ectoderm, mesoderm and endoderm. The notochord begins secreting growth factors which stimulate the ectoderm to start raising up because of the growth factors from notochord. This creates a folded and depression above the notochord. The neural crest cells develop from the top portion. These edges grow towards each other and fuse to form the Neural Tube. Before fusion the neural crest cells went away and formed many other things.
The neural tube forms spinal cord and the notochord forms nucleus polposis. Anterior neural pore doesn't develop then it is called anencephaly which has Increase AFP and AChe. ssociated iwth Low folate and Maternal DM. If posterior notochord is not developed, then you can get Spina Bifida. Anterio 25 and posterio 27th day.
CNS DEVELOPMENT
3 pirmary swellings - prosencephalon, mesencephalon and the rhombencephalon. There are 5 secondary swelling. Prosencephalon becomes telencephalon and diencephalon. Telencephalon becomes cerebrum. Diencephalon becomes third ventricle. Midbrain from mesencephalon. Rhombencephaolon becomes metencephalon and myelincephalon. Mesencephalon becomes PONs and cerebellum. And the myelencephalon becomes medulla.
SPINAL CORD DEVELOPMENT
10 سال پیش
در تاریخ 1393/07/04 منتشر شده
است.
34,306
بـار بازدید شده