• Development and Reproduction
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• v.27 no.3
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• pp.137-147
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• 2023

Pharyngeal pouches are an important epithelial structure controlling facial skeletal development in vertebrates. A series of pouches arise sequentially in the pharyngeal endoderm through collective cell migration followed by rearrangement of pouch-forming cells. While crucial transcription factors and signaling molecules have been identified in pouch formation, a role for Neuropilins (Nrps) in pouch development has not yet been analyzed in any vertebrates. Nrps are cell surface receptors essential for angiogenesis and axon guidance. In all vertebrates, the two Nrp family members, Nrp1 and Nrp2, are conserved in the genome, with two paralogs for Nrp1 (Nrp1a and Nrp1b) and Nrp2 (Nrp2a and Nrp2b) being identified in zebrafish. Here, I report a potential requirement of Nrp signaling in pouch development in zebrafish. nrp1a and nrp2b were expressed in the developing pouches, with sema3d, a ligand for Nrps, being expressed in the pouches. Knocking down Nrps signaling in the pharyngeal endoderm led to severe defects in pouches and facial cartilages. In addition, blocking Mitogen-activated protein kinase (MAPK) activities, a downstream effector of Nrp signaling, in the pharyngeal endoderm caused similar defects in pouches and facial skeleton to those by knocking down Nrps signaling. My results suggest that Nrp signaling acts for pouch formation through MAPK.

• Archives of Plastic Surgery
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• v.41 no.1
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• pp.12-18
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• 2014

In patients having a short nose with a short septal length and/or severe columellar retraction, a septal extension graft is a good solution, as it allows the dome to move caudally and pushes down the columellar base. Fixing the medial crura of the alar cartilages to a septal extension graft leads to an uncomfortably rigid nasal tip and columella, and results in unnatural facial animation. Further, because of the relatively small and weak septal cartilage in the East Asian population, undercorrection of a short nose is not uncommon. To overcome these shortcomings, we have used the septal extension graft combined with a derotation graft. Among 113 patients who underwent the combined procedure, 82 patients had a short nose deformity alone; the remaining 31 patients had a short nose with columellar retraction. Thirty-two patients complained of nasal tip stiffness caused by a septal extension graft from previous operations. In addition to the septal extension graft, a derotation graft was used for bridging the gap between the alar cartilages and the septal extension graft for tip lengthening. Satisfactory results were obtained in 102 (90%) patients. Eleven (10%) patients required revision surgery. This combination method is a good surgical option for patients who have a short nose with small septal cartilages and do not have sufficient cartilage for tip lengthening by using a septal extension graft alone. It can also overcome the postoperative nasal tip rigidity of a septal extension graft.

• Development and Reproduction
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• v.26 no.1
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• pp.23-36
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• 2022

Pharyngeal pouches, a series of outgrowths of the pharyngeal endoderm, are a key epithelial structure governing facial skeleton development in vertebrates. Pouch formation is achieved through collective cell migration and rearrangement of pouch-forming cells controlled by actin cytoskeleton dynamics. While essential transcription factors and signaling molecules have been identified in pouch formation, regulators of actin cytoskeleton dynamics have not been reported yet in any vertebrates. Cofilin1-like (Cfl1l) is a fish-specific member of the Actin-depolymerizing factor (ADF)/Cofilin family, a critical regulator of actin cytoskeleton dynamics in eukaryotic cells. Here, we report the expression and function of cfl1l in pouch development in zebrafish. We first showed that fish cfl1l might be an ortholog of vertebrate adf, based on phylogenetic analysis of vertebrate adf and cfl genes. During pouch formation, cfl1l was expressed sequentially in the developing pouches but not in the posterior cell mass in which future pouch-forming cells are present. However, pouches, as well as facial cartilages whose development is dependent upon pouch formation, were unaffected by loss-of-function mutations in cfl1l. Although it could not be completely ruled out a possibility of a genetic redundancy of Cfl1l with other Cfls, our results suggest that the cfl1l expression in the developing pouches might be dispensable for regulating actin cytoskeleton dynamics in pouch-forming cells.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.5
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• pp.406-415
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• 2010

Purpose: The secondary correction of cleft lip nasal deformity still presents a difficult surgical problems. The present study was aimed to investigate the usefulness of Bardach's technique for secondary correction of cleft lip nasal deformity. Materials and Methods: The subjects were eight patients with unilateral and bilateral cleft lip nasal deformity, who had secondary correction by using Bardach's rhinoplasty technique. Age range was from 2 to 21 years and mean age was 10.6 years. There were 3 boys and 5 girls. Six patients had bilateral and two patients had unilateral cleft lip. Facial photographs were taken before and twenty days after the operation. By using Adobe photoshop, the columella height and the nostril width were measured from the facial frontal photograph and Worm's eye view. The degree of improvement was calculated and statistically analyzed. Results: The degree of improvement of the columella length and the nostril width after Bardach's technique was $70.39{\pm}50.14%$ and $-22.93{\pm}0.15%$ respectively. Bardach's technique resulted in projecting the nasal tip, lengthening the columella, medially advancing the alar bases, restructuring the lower lateral cartilages, and changing orientation of the nostrils from horizontal to oblique. The profile view shows projection of the nasal tip, lengthening of the columella, and the change in the nasolabial angle. The scars remained at the philtrum were matter little in compared with improvement of the nasal appearance. Conclusion: These results indicate that Bardach's technique is an useful surgical technique for secondary correction of cleft lip nasal deformity.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.630-637
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• 2014

A long nose with a drooping tip is a major aesthetic problem. It creates a negative and aged appearance and looks worse when smiling. In order to rectify this problem, the underlying anatomical causes should be understood and corrected simultaneously to optimize surgical outcomes. The causes of a drooping tip of a long nose are generally classified into two mechanisms. Static causes usually result from malposition and incorrect innate shape of the nasal structure: the nasal septum, upper and lower lateral cartilages, and the ligaments in between. The dynamic causes result from the facial expression muscles, the depressor septi nasi muscle, and the levator labii superioris alaeque nasi muscle. The depressor septi nasi depresses the nasal tip and the levator labii superioris alaeque nasi pulls the alar base upwards. Many surgical methods have been introduced, but partial approaches to correct such deformities generally do not satisfy East Asians, making the problem more challenging to surgeons. Typically, East Asians have thick nasal tip soft tissue and skin, and a depressed columella and alar bases. The authors suggest that multifactorial approaches to static and dynamic factors along with ancillary causes should be considered for correcting the drooping tip of the long noses of East Asians.