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The skeleton and muscles
Published in Frank J. Dye, Human Life Before Birth, 2019
Two general types of osteogenesis (bone formation) occur: intramembranous ossification and endochondral ossification (ossification is the formation of bone substance). Both types begin with mesenchymal cells (loose connective tissue), which are usually of mesodermal origin. However, the cranial neural crest contributes to bone formation in the head.
Nutrition in pregnancy
Published in Anne Lee, Sally Inch, David Finnigan, Therapeutics in Pregnancy and Lactation, 2019
Cases suggesting a link between excessive vitamin A ingestion during pregnancy and fetal malformations have been reported.52 In 1987, women in the USA were recommended not to take more than 10 000 IU of vitamin A per day.53 Since then two case—control studies have concluded that children born to women consuming vitamin A at levels found in supplements are not at increased risk for birth defects.54,55 A recent prospective study56 investigating birth defects and the intake of vitamin A from food and supplements in almost 23 000 pregnant women found that consumption of less than 10 000 IU of vitamin A appeared safe. However, the authors estimated that the ingestion of larger amounts was associated with birth defects in one in 57 babies. There was a marked increase in incidence of birth defects of structures arising from the cranial neural crest (craniofacial, central nervous system, thymic and heart defects). These data indicate that large doses of vitamin A must be regarded as potentially harmful to the fetus.
Head and Neck
Published in Rui Diogo, Drew M. Noden, Christopher M. Smith, Julia Molnar, Julia C. Boughner, Claudia Barrocas, Joana Bruno, Understanding Human Anatomy and Pathology, 2018
Rui Diogo, Drew M. Noden, Christopher M. Smith, Julia Molnar, Julia C. Boughner, Claudia Barrocas, Joana Bruno
Because cranial neural crest cells contribute to so many structures, genetic defects, or environmental teratogens that affect the proliferation, migration, or interactions of these cells will have widespread effects across the head. For instance, a defect may cause not only hypoplasia (underdevelopment) of oral and facial structures, but also of the ears and the glands that are derived from the branchial arches (thymus, thyroid C cells, and parathyroid glands). Once mesenchymal cells from the neural crest arrive in the arch, these cells interact via intricate back-and-forth signaling with the epidermis to form teeth, nails, hair, salivary, and sweat glands. Thus, ectodermal dysplasia syndromes, which result from genetic disturbances of the signaling process affect all these structures. Moreover, the most posterior stream of migration from the cranial neural crest becomes incorporated into the great outflow vessels of the heart (Plate 3.4). This contribution of neural crest cells to heart development explains why developmental defects of the cranial neural crest often result in heart defects as well as face, jaw, and ear defects. In a direct clinical example, patients with the congenital muscle disease DiGeorge syndrome must be evaluated for heart defects and immune deficiencies as well as facial defects (see Box 3.2 for further information about developmental links between the heart and head and DiGeorge syndrome).
Extracellular Matrix Remodeling During Palate Development
Published in Organogenesis, 2020
Xia Wang, Chunman Li, Zeyao Zhu, Li Yuan, Wood Yee Chan, Ou Sha
Talin (Tln) is one of the important intracellular proteins which activates integrins by binding to its β subunit.93,94 Two Tln isoforms are present in most vertebrates95 and three in zebrafish.96 In zebrafish, tln1 is required for the cranial neural crest cell proliferation during palate morphogenesis.97 In mice, global loss of Tln1 leads to embryonic lethality during gastrulation98, while Tln2 null mice are viable and fertile.99 Conditional mouse models would provide more evidence on how Talin engages in Integrin signal transduction during palate development.
Survival of human periodontal ligament fibroblast cells in Cornisol and HBSS for transportation of avulsed teeth: a comparative ex vivo study
Published in Acta Odontologica Scandinavica, 2021
Shruti Singh, Sandya Kini, Swathi Pai, Rajeshwari H. R., Tina Puthen Purayil
PDFC have clonal proliferation capability and express specific markers of mesenchymal stem cells, embryonic stem cells and neural crest stem cells [11]. The corneal cells and PDFC are said to develop from same pathway of cranial neural crest and have similar gene expressions at cellular level [12]. Both share similar extra-cellular matrix components such as collagen type II, collagen type V, collagen type VI, MMP1 (matrix metalloproteinase 1) and MMP3 (matrix metalloproteinase 3) [13]. Therefore, the media used to preserve corneal cells could also be effective to preserve the viability of PDFC [14].
Extraocular muscle hypoplasia associated with Axenfeld-Rieger syndrome
Published in Strabismus, 2021
Milo De Decker, Catherine Cassiman, Ingele Casteels, Koenraad Devriendt, Patricia Delbeke
Ocular and systemic abnormalities in patients with ARS comprise tissues derived from cranial neural crest cells. In contrast, extraocular muscles develop from the superior and inferior mesodermal complex. Therefore, the association of muscle hypoplasia/aplasia with ARS is not expected.11