Akiko Tani

Regeneration of tracheal epithelium using a collagen vitrigel-sponge scaffold containing basic fibroblast growth factor.

Objectives: Our group has had good results in tracheal mucosal regeneration using a collagen vitrigel–sponge scaffold in an animal model. In this study, the effectiveness of this scaffold with the application of basic fibroblast growth factor (b-FGF) was investigated. Methods: A collagen vitrigel–sponge scaffold was fabricated with simultaneous addition of b-FGF. Three types of collagen vitrigel–sponge scaffolds were made: No b-FGF, 10 ng of b-FGF, and 100 ng of b-FGF. At 3, 5, 7, and 14 days after implantation in rats, the tracheas were removed and histologically evaluated. The regeneration of mucosal epithelium and the subepithelial layer was evaluated. Results: Mucosal epithelium, including pseudostratified epithelium and ciliated cells, regenerated earlier in the scaffolds when b-FGF was applied than when b-FGF was not applied. Regeneration of the subepithelial layer, infiltration of inflammatory cells and fibroblasts, and angiogenesis were promoted earlier in the scaffolds with b-FGF application. Conclusions: Our technique for tracheal reconstruction using collagen vitrigel–sponge scaffolds with b-FGF application affords a feasible approach for accelerating the regeneration of the intraluminal surface and subepithelial layer of tracheal tissue.

Bioengineered prosthesis with allogenic heterotopic fibroblasts for cricoid regeneration

This study aimed to determine the effectiveness of a bioengineered prosthesis with allogenic heterotopic fibroblasts for cricoid regeneration.

Collagen vitrigel scaffold for regenerative medicine of the trachea: Experimental study and quantitative evaluation

Abstract Conclusion: Our technique for tracheal regeneration using a collagen vitrigel scaffold affords a feasible approach for accelerating epithelial regeneration on the intraluminal surface of the host tracheal defect. Objectives: The purpose of the study was to quantitatively evaluate the effectiveness of a collagen vitrigel scaffold for the regeneration of the tracheal epithelium. Methods: The collagen vitrigel scaffold was developed by conjugating a collagen vitrigel membrane to a collagen sponge to promote both epithelial cell growth and mesenchymal cell infiltration. The collagen vitrigel scaffold was implanted into tracheal defects in rats as the vitrigel model, and a conventional collagen sponge was implanted as a control model. The structure of the regenerated tissue was observed and thickness of the epithelium was quantitatively evaluated by histological examination. Results: Histological findings showed the surface of the collagen vitrigel scaffold to be flat in comparison with that of the conventional collagen sponge. At 7, 14, and 28 days post-implantation, the average thickness of the regenerated epithelial layer in the vitrigel model group was greater than that in the control group.

Bioengineered trachea using autologous chondrocytes for regeneration of tracheal cartilage in a rabbit model.

In this study, a bioengineered trachea composed of autologous chondrocytes was developed, and its effect on cartilaginous regeneration was evaluated by implantation into tracheal defects in rabbits.

Regenerative process of tracheal epithelium using a collagen vitrigel sponge scaffold

Our group has developed a collagen vitrigel sponge scaffold containing basic fibroblast growth factor (b‐FGF) for tracheal reconstruction. In this study, we have investigated the regenerative process of tracheal epithelium histologically and morphologically.

Restricted infection of murine cytomegalovirus (MCMV) in neonatal mice with MCMV-induced sensorineural hearing loss

BACKGROUND Congenital infection with human Cytomegalovirus (HCMV) is known to be a causative agent of sensorineural hearing loss (SNHL). OBJECTIVES To clarify the nongenetic etiology of SNHL by identifying the Cytomegalovirus (CMV)-infected region in the cochleae. STUDY DESIGN We established an animal model of SNHL by injecting neonatal Balb/c mice with intracerebral murine Cytomegalovirus (MCMV) within 24h after delivery. RESULTS At 3 weeks of age, unilateral and bilateral SNHL were observed in 24% (5/21) and 29% (6/21) of the mice, respectively. SNHL thereafter progressed, with 79% of mice developing bilateral SNHL by 6 weeks of age. MCMV antigens and DNA were detected in the spiral ganglion, and cells surrounding the meninges and scala tympani at 1 week of age. However, both MCMV antigens and DNA had completely disappeared by 2 weeks of age. It is possible that the MCMV reached the spiral ganglion via cerebrospinal fluid as the result of meningitis, as the stria vascularis was found to be MCMV antigen negative. Myosin VI expression in the outer hair cells was lost at 3 weeks of age. MCMV and myosin VI expression disappeared before and during SNHL progression, respectively. CONCLUSIONS There was a definite lag time between the period in which MCMV antigens/DNA-positive cells were observed and that in which SNHL developed and myosin VI-negative hair cells were observed. Further study is needed to explore the role of MCMV in the loss of myosin VI expression in the outer hair cells.

Heparin cross-linked collagen sponge scaffolds improve functional regeneration of rat tracheal epithelium.

Tracheal epithelial cells maintain airway homeostasis by mediating mucociliary clearance. Following tracheal reconstruction, timely epithelial regeneration is required to prevent respiratory compromise and infectious diseases. To achieve rapid tracheal epithelial regeneration, a heparin cross‐linked collagen sponge containing fibroblast growth factor‐2 (FGF‐2) was prepared as a graft for tracheal reconstruction. The heparin cross‐linked sponge exhibited a high FGF‐2 retaining capacity, and tracheal epithelial and mesenchymal cells cultured in this sponge containing FGF‐2 showed high proliferative capacities. Subsequently, heparin‐free collagen sponge scaffolds (C/F scaffold) and collagen sponge scaffolds cross‐linked with 10 μg/ml heparin retained FGF‐2 (C/H10/F scaffold), and were transplanted into rats with tracheal defects. Invasion of both epithelial and non‐epithelial cells was greater in rats treated with the C/H10/F scaffold at 1 week post‐transplantation than in rats treated with the C/F scaffold. Moreover, at 2 weeks after transplantation, improved cilia formation was observed in the C/H10/F scaffold group, with higher motility and more potent posterior–anterior flow generation than in the C/F scaffold group. These results suggest that heparin improves functional regeneration of tracheal epithelium. Copyright

Chemoselection combined with alternating chemoradiotherapy or surgery for hypopharyngeal cancer

In order to make possible organ preservation, since 2007 our hospital has performed induction chemotherapy (ICT) with cisplatin and 5‐fluorouracil (PF) for hypopharyngeal cancer as chemoselection, followed by alternating chemoradiotherapy (ACRT) with docetaxel, cisplatin, and 5‐fluorouracil in (TPF) good responders and curative surgery was used in poor responders.

Assessment of non-invasive chronic fungal rhinosinusitis by cone beam CT: comparison with multidetector CT findings

OBJECTIVE To investigate the accuracy of cone beam CT (CBCT) to diagnose non-invasive chronic fungal rhinosinusitis. METHODS Preoperative CT evaluation of non-invasive chronic fungal rhinosinusitis was performed by CBCT (3D Accuitomo 170®) and traditional multidetector CT (MDCT) (Aquilion 32®) in 13 and 38 patients with non-invasive chronic fungal maxillary sinusitis, respectively, in different facilities. Detection of intrasinus calcification was compared between these two groups. RESULTS Detection of intrasinus calcification in patients with non-invasive chronic fungal maxillary sinusitis was higher in the MDCT group (84.2%) than the CBCT group (46.2%). CONCLUSION CBCT is inferior to MDCT in detection of intrasinus calcification in patients with non-invasive chronic fungal maxillary sinusitis. CBCT is frequently used in the screening of the paranasal lesion, but it is not enough to evaluate non-invasive chronic fungal maxillary sinusitis alone. STUDY DESIGN Retrospective study.

Parotid lymphangioma associated with facial nerve paralysis

Parotid lymphangioma is a relatively rare disease that is usually detected in infancy or early childhood, and which has typical features. Clinical reports of facial nerve paralysis caused by lymphangioma, however, are very rare. Usually, facial nerve paralysis in a child suggests malignancy. Here we report a very rare case of parotid lymphangioma associated with facial nerve paralysis. A 7‐year‐old boy was admitted to hospital with a rapidly enlarging mass in the left parotid region. Left peripheral‐type facial nerve paralysis was also noted. Computed tomography and magnetic resonance imaging also revealed multiple cystic lesions. Open biopsy was undertaken in order to investigate the cause of the facial nerve paralysis. The histopathological findings of the excised tumor were consistent with lymphangioma. Prednisone (40 mg/day) was given in a tapering dose schedule. Facial nerve paralysis was completely cured 1 month after treatment. There has been no recurrent facial nerve paralysis for eight years.