Shape optimization of continua using NURBS as basis functions

The present paper introduces a numerical solution to shape optimization problems of domains in which boundary value problems of partial differential equations are defined. In the present paper, the finite element method using NURBS as basis functions in the Galerkin method is applied to solve the boundary value problems and to solve a reshaping problem generated by the H1 gradient method for shape optimization, which has been developed as a general solution to shape optimization problems. Numerical examples of linear elastic continua illustrate that this solution works as well as using the conventional finite element method.This paper was presented in WCSMO-9, Shizuoka

Gastric lipomatosis treated by total gastrectomy: a case report

Abstract Background Gastric lipomatosis is characterized by multiple gastric lipomas or a diffuse gastric infiltration of the submucosal or subserosal layer by the adipose tissue; diffuse-type gastric lipomatosis is an extremely rare condition. Here, we present the case of a patient with gastric lipomatosis treated by total gastrectomy. Case presentation A 54-year-old man diagnosed with gastric submucosal tumor in 2008 was referred to our hospital for further examination and treatment in September 2016. Upper gastrointestinal endoscopy revealed a submucosal tumor with an associated ulcer on the anterior wall of the lower body of the stomach. A compressing mass was observed on the anterior wall of the greater curvature and the posterior wall of the stomach. Following a biopsy of the submucosal tumor and ulcer, lipoma without malignancy was diagnosed by microscopy. A giant gastric lipoma was suspected because endoscopic ultrasound revealed a high-echoic lesion on the antral wall that extended to the stomach. Therefore, total gastrectomy was performed, and gastric lipomatosis was confirmed by a histological examination of the resected specimen. Conclusions Surgical treatment is a highly effective treatment for symptomatic gastric lipomatosis with extensive involvement or multiple lipomas and can be used for patient diagnosis

Transplantation of hybrid adipose-derived stem cell sheet with autologous peritoneum: An in vivo feasibility study

Introduction: In regenerative medicine, cell sheet engineering has various advantages, including the retention of cells at the transplantation site for a longer period and the local delivery of growth factors and cytokines. Adipose-derived stem cell (ASC) is widely used owing to their various functions such as wound healing, immunomodulation, and nerve regeneration, in addition to their ability to differentiate into adipocytes, chondrocytes, and osteoblasts. ASC sheet generated using cell sheet engineering is considered effective in preventing anastomotic leakage, a serious postoperative complication in gastrointestinal surgery. However, the ASC sheet is too soft, thin, and brittle to handle with laparoscopic forceps during the operation. Therefore, we considered using the peritoneum, which is stiff and easy to collect while operating, as an alternative support. In this study, we explored the feasibility of using the peritoneum as a support for the precise transplantation of ASC sheets during surgery. Methods: ASCs were isolated from the subcutaneous fat of the inguinal region of Sprague-Dawley (SD) transgenic rats expressing green fluorescent protein. ASCs were cultured until passage 3, seeded in temperature-responsive culture dishes, and the resulting ASC sheet was harvested at more than 80% confluency. Non-transgenic SD rats were used for transplant experiments. The wall peritoneum was harvested from SD rats following laparotomy, and hybrid adipose-derived stem cell (HASC) sheet was prepared by laminating the peritoneum with ASC sheet. The cell sheets were transplanted on the backs of SD rats following the incision. On post-transplantation days 3 and 7, the specimens were extracted. ASC and HASC sheets were then compared macroscopically and histopathologically. Results: HASC sheet transplantation was macroscopically and histopathologically more effective than ASC sheet transplantation. The peritoneum provided sufficient stiffness as a support for precise transplantation. Conclusion: The newly developed HASC sheet, which combine the advantages of ASC sheet with those of the peritoneum, could be more useful for clinical application than the ASC sheet alone