Ultrastructure of initial nasal process cell fusion in spontaneous and 6-aminonicotinamide-induced mouse embryo cleft lip

Teratology ◽  
1983 ◽  
Vol 28 (1) ◽  
pp. 91-101 ◽  
Author(s):  
D. G. Trasler ◽  
L. Ohannessian
2015 ◽  
Vol 20 (5) ◽  
pp. 118-125 ◽  
Author(s):  
Daniela Gamba Garib ◽  
Julia Petruccelli Rosar ◽  
Renata Sathler ◽  
Terumi Okada Ozawa

Introduction:Cleft lip and palate are craniofacial anomalies highly prevalent in the overall population. In oral clefts involving the alveolar ridge, variations of number, shape, size and position are observed in maxillary lateral incisors. The objective of this manuscript is to elucidate the embryonic origin of maxillary lateral incisors in order to understand the etiology of these variations.Contextualization: The hypothesis that orofacial clefts would split maxillary lateral incisor buds has been previously reported. However, recent studies showed that maxillary lateral incisors have dual embryonic origin, being partially formed by both the medial nasal process and the maxillary process. In other words, the mesial half of the lateral incisor seems to come from the medial nasal process while the distal half of the lateral incisor originates from the maxillary process. In cleft patients, these processes do not fuse, which results in different numerical and positional patterns for lateral incisors relating to the alveolar cleft. In addition to these considerations, this study proposes a nomenclature for maxillary lateral incisors in patients with cleft lip and palate, based on embryology and lateral incisors position in relation to the alveolar cleft.Conclusion:Embryological knowledge on the dual origin of maxillary lateral incisors and the use of a proper nomenclature for their numerical and positional variations renders appropriate communication among professionals and treatment planning easier, in addition to standardizing research analysis.


Science ◽  
1983 ◽  
Vol 220 (4603) ◽  
pp. 1300-1302 ◽  
Author(s):  
J McGrath ◽  
D Solter

2019 ◽  
Vol 5 (10) ◽  
pp. eaax4199 ◽  
Author(s):  
João Frade ◽  
Shoma Nakagawa ◽  
Paola Cortes ◽  
Umberto di Vicino ◽  
Neus Romo ◽  
...  

Cells with high ploidy content are common in mammalian extraembryonic and adult tissues. Cell-to-cell fusion generates polyploid cells during mammalian development and tissue regeneration. However, whether increased ploidy can be occasionally tolerated in embryonic lineages still remains largely unknown. Here, we show that pluripotent, fusion-derived tetraploid cells, when injected in a recipient mouse blastocyst, can generate diploid cells upon ploidy reduction. The generated diploid cells form part of the adult tissues in mouse chimeras. Parental chromosomes in pluripotent tetraploid cells are segregated through tripolar mitosis both randomly and nonrandomly and without aneuploidy. Tetraploid-derived diploid cells show a differentiated phenotype. Overall, we discovered an unexpected process of controlled genome reduction in pluripotent tetraploid cells. This mechanism can ultimately generate diploid cells during mouse embryo development and should also be considered for cell fusion–mediated tissue regeneration approaches.


2013 ◽  
Vol 14 (2) ◽  
pp. 332-338
Author(s):  
P Sudhakar ◽  
Sai Prakash Adusumilli ◽  
Bhaskar Mummidi ◽  
KV Baburam Reddy ◽  
CH Hanumantha Rao ◽  
...  

ABSTRACT Aim The present case report describes the importance of interdisciplinary approach and gives an understanding on management of an adolescent with unilateral cleft lip and palate. Background Failure of fusion between medial nasal process and maxillary process or between the palatal process leads to the formation of clefts. Clefts are result of genetic or environmental factors or a combination of both. Common dental problems associated with clefts includes anterior and posterior crossbites, hypodontia, malformation and abnormal eruption pattern. Case report A girl, aged 15 years reported with a chief complaint of unesthetic appearance of her maxillary anterior teeth. She had unilateral cleft lip and palate and had received cheiloplasty and palatoplasty when she was in young age and rhinoplasty when she was 14 years of age. At pretreatment evaluation, she had concave profile with maxillary arch constriction and oroantral fistula and mesially tipped maxillary left canine. Conclusion This patient's treatment was unconventional, but it was successful in significantly improving her masticatory function and smile, along with favorable dental and facial results. Generalized esthetics and function were significantly improved in this patient without orthognathic surgery, and treatment results were stable 3 years after the appliance removal. Clinical considerations, sequencing of treatment phases as shown in this case report can be utilized while treating an adolescent with cleft lip and palate. Clinical significance If the skeletal discrepancy is mild and esthetic concerns are minimal, dental compensation by orthodontic treatment alone might be recommended. The cephalometric analysis and prediction tracings provide further information for deciding whether a patient can be treated by orthodontics alone, or by orthodontics and an orthognathic surgical procedure. A change in axial inclination of the teeth can camouflage the skeletal relationship adequately. However, one should be cautious in a growing patient, because he or she might outgrow the dental correction so that ultimately skeletal surgery would be indicated. How to cite this article Adusumilli SP, Sudhakar P, Mummidi B, Reddy KVB, Rao CHH, Raju BHVRK. Interdisciplinary Treatment of an Adolescent with Unilateral Cleft Lip and Palate. J Contemp Dent Pract 2013;14(2):332-338.


Development ◽  
1981 ◽  
Vol 63 (1) ◽  
pp. 53-66
Author(s):  
Guillermo Millicovsky ◽  
Malcolm C. Johnston

Epithelial cells of the C57B1/6J mouse embryo participate in a temporal sequence of events associated with the approximation, fusion and consolidation of components of the facial primordia into a definitive structure. These cells lose their surface microvilli, and after a brief period of quiescence they begin to fill the grooves separating facial constituents by producing a series of surface projections that increase in size and complexity as the process of fusion nears termination. Cessation of surface activity and the restoration of epithelial microvilli indicate the end of the temporal sequence. Significantly, the epithelial cells of rimary palates of embryos with genetically- and phenytoin-induced cleft lip remain unchanged and do not participate in fusion. This epithelial sequence has not been described previously and we suggest that all of its steps may be critical to the normal development of the mammalian face.


Author(s):  
Elizabeth S. Priori ◽  
T. Shigematsu ◽  
B. Myers ◽  
L. Dmochowski

Spontaneous release of type C virus particles in long-term cultures of mouse embryo cells as well as induction of similar particles in mouse embryo cell cultures with IUDR or BUDR have been reported. The presence of type C virus particles in cultures of normal rat embryos has not been reported.NB-1, a culture derived from embryos of a New Zealand Black (NB) rat (rats obtained from Mr. Samuel M. Poiley, N.C.I., Bethesda, Md.) and grown in McCoy's 5A medium supplemented with 20% fetal calf serum was passaged weekly. Extracellular virus particles similar to murine leukemia particles appeared in the 22nd subculture. General appearance of cells in passage 23 is shown in Fig. 1. Two budding figures and one immature type C virus particle may be seen in Fig. 2. The virus particles and budding were present in all further passages examined (currently passage 39). Various stages of budding are shown in Figs. 3a,b,c,d. Appearance of a mature virus particle is shown in Fig. 4.


Author(s):  
Marc Lenburg ◽  
Rulang Jiang ◽  
Lengya Cheng ◽  
Laura Grabel

We are interested in defining the cell-cell and cell-matrix interactions that help direct the differentiation of extraembryonic endoderm in the peri-implantation mouse embryo. At the blastocyst stage the mouse embryo consists of an outer layer of trophectoderm surrounding the fluid-filled blastocoel cavity and an eccentrically located inner cell mass. On the free surface of the inner cell mass, facing the blastocoel cavity, a layer of primitive endoderm forms. Primitive endoderm then generates two distinct cell types; parietal endoderm (PE) which migrates along the inner surface of the trophectoderm and secretes large amounts of basement membrane components as well as tissue-type plasminogen activator (tPA), and visceral endoderm (VE), a columnar epithelial layer characterized by tight junctions, microvilli, and the synthesis and secretion of α-fetoprotein. As these events occur after implantation, we have turned to the F9 teratocarcinoma system as an in vitro model for examining the differentiation of these cell types. When F9 cells are treated in monolayer with retinoic acid plus cyclic-AMP, they differentiate into PE. In contrast, when F9 cells are treated in suspension with retinoic acid, they form embryoid bodies (EBs) which consist of an outer layer of VE and an inner core of undifferentiated stem cells. In addition, we have established that when VE containing embryoid bodies are plated on a fibronectin coated substrate, PE migrates onto the matrix and this interaction is inhibited by RGDS as well as antibodies directed against the β1 integrin subunit. This transition is accompanied by a significant increase in the level of tPA in the PE cells. Thus, the outgrowth system provides a spatially appropriate model for studying the differentiation and migration of PE from a VE precursor.


Author(s):  
A.E. Sutherland ◽  
P.G. Calarco ◽  
C.H. Damsky

Cell-extracellular matrix (ECM) interactions mediated by the integrin family of receptors are critical for morphogenesis and may also play a regulatory role in differentiation during early development. We have examined the onset of expression of individual integrin subunit proteins in the early mouse embryo, and their roles in early morphogenetic events. As detected by immunoprecipitation, the α6, αV, β1, and β3 subunits are detected as early as the 4-cell stage, α5 at the hatched blastocyst stage and αl and α3 following blastocyst attachment. We tested the role of these integrins in the attachment and migratory activity of two cell populations of the early mouse embryo: the trophoblast giant cells, which invade the uterine stroma and ultimately contribute to the chorio-allantoic placenta, and the parietal endoderm, which migrates over the inner surface of the trophoblast and ultimately forms Reichert's membrane and the parietal yolk sac. Experiments were done in serum-free medium on substrates coated with laminin (Ln) and fibronectin (Fn). Trophoblast outgrowth occurs on Ln and its E8 fragment (long arm), but not on the E1’ fragment (cross region) (Figs. 1, 2 ). This outgrowth is inhibited by anti-E8, anti-Ln, and by the anti-β1 family antiserum anti-ECMR, but not by anti-αV or the function-perturbing GoH3 antibody that recognizes the α6/β1 integrin, a major Ln (E8) receptor. This suggests that trophoblast outgrowth on Ln or E8 is mediated by a different β1 integrin such as α3/β1. Early stages of trophoblast outgrowth (up to 48 hours) on Fn are inhibited by anti-Fn and by function-perturbing anti-αV antibodies, whereas at later times outgrowth becomes insensitive to anti-αV but remains sensitive to the anti-β1 family antiserum anti-ECMr, indicating that trophoblast cells modulate their interaction with Fn during outgrowth. Trophoblast outgrowth on vitronectin (Vn) is sensitive to anti-αV antibodies throughout the 5-day period examined.


2019 ◽  
Vol 4 (5) ◽  
pp. 878-892
Author(s):  
Joseph A. Napoli ◽  
Linda D. Vallino

Purpose The 2 most commonly used operations to treat velopharyngeal inadequacy (VPI) are superiorly based pharyngeal flap and sphincter pharyngoplasty, both of which may result in hyponasal speech and airway obstruction. The purpose of this article is to (a) describe the bilateral buccal flap revision palatoplasty (BBFRP) as an alternative technique to manage VPI while minimizing these risks and (b) conduct a systematic review of the evidence of BBFRP on speech and other clinical outcomes. A report comparing the speech of a child with hypernasality before and after BBFRP is presented. Method A review of databases was conducted for studies of buccal flaps to treat VPI. Using the principles of a systematic review, the articles were read, and data were abstracted for study characteristics that were developed a priori. With respect to the case report, speech and instrumental data from a child with repaired cleft lip and palate and hypernasal speech were collected and analyzed before and after surgery. Results Eight articles were included in the analysis. The results were positive, and the evidence is in favor of BBFRP in improving velopharyngeal function, while minimizing the risk of hyponasal speech and obstructive sleep apnea. Before surgery, the child's speech was characterized by moderate hypernasality, and after surgery, it was judged to be within normal limits. Conclusion Based on clinical experience and results from the systematic review, there is sufficient evidence that the buccal flap is effective in improving resonance and minimizing obstructive sleep apnea. We recommend BBFRP as another approach in selected patients to manage VPI. Supplemental Material https://doi.org/10.23641/asha.9919352


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