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Regeneration of esophagus using a scaffold-free biomimetic structure created with bio-three-dimensional printing
Get PDFVarious strategies have been attempted to replace esophageal defects with natural or artificial substitutes using tissue engineering. However, these methods have not yet reached clinical application because
of the high risks related to their immunogenicity or insufficient biocompatibility. In this study, we developed a scaffold-free structure with a mixture of cell types using bio-three-dimensional (3D) printing technology
and assessed its characteristics in vitro and in vivo after transplantation into rats. Normal human dermal fibroblasts, human esophageal smooth muscle cells, human bone marrow-derived mesenchymal stem cells,
and human umbilical vein endothelial cells were purchased and used as a cell source.
After the preparation of multicellular spheroids, esophageal-like tube structures were prepared by bio-3D printing. The structures were matured in a bioreactor
and transplanted into 10-12- week-old F344 male rats as esophageal grafts under general anesthesia. Mechanical and histochemical assessment of the structures were performed.
Among 4 types of structures evaluated, those with the larger proportion of mesenchymal stem cells tended to show greater strength and expansion on mechanical testing and highly expressed α-smooth muscle actin and vascular endothelial growth factor on immunohistochemistry. Therefore, the structure with the larger proportion of mesenchymal stem cells was selected for transplantation. The scaffold-free structures had sufficient strength for transplantation between the esophagus and stomach using silicon stents.The structures were maintained in vivo for 30 days after transplantation. Smooth muscle cells were maintained, and flat epithelium extended and covered the inner surface of the lumen. Food had also passed through the structure.
These results suggested that the esophagus-like scaffold-free tubular structures created using bio-3D printing could hold promise as a substitute for the repair of esophageal defects
Clinical Features of Anti-MDA5 Antibody-positive Rapidly Progressive Interstitial Lung Disease without Signs of Dermatomyositis
Get PDFAnti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody is associated
with rapidly progressive interstitial lung disease (RP-ILD) in patients with clinically amyopathic dermatomyositis (CADM) or dermatomyositis (DM). We herein report three Japanese cases of anti-MDA5 antibody-positive RP-ILD without signs of CADM or DM. High-resolution computed tomography revealed patchy or subpleural distribution of consolidations and/or ground-glass opacities accompanied by traction bronchiectasis.
All patients succumbed to respiratory failure within two months. Anti-MDA5 antibody-positive RP-ILD without signs of CADM or DM should be included in the differential diagnosis of acute/subacute ILD.
Measurement of anti-MDA5 antibody and an intensive immunosuppressive regimen might rescue these patients from RP-ILD
第4級アンモニウムと無機ナノシートを用いたエンテロバクター・クロアカに対する抗菌効果の増強
Get PDF長崎大学学位論文 [学位記番号]博（医歯薬）甲第1134号 [学位授与年月日]平成31年3月20
