Development of a skeletal muscle sheet with direct reprogramming-induced myoblasts on a nanogel-cross-linked porous freeze-dried gel scaffold in a mouse gastroschisis model.

PURPOSE: In this study, we attempted to create skeletal muscle sheets made of directly converted myoblasts (dMBs) with a nanogel scaffold on a biosheet using a mouse gastroschisis model. METHODS: dMBs were prepared by the co-transfection of MYOD1 and MYCL into human fibroblasts. Silicon tubes were implanted under the skin of NOG/SCID mice, and biosheets were formed. The nanogel was a nanoscale hydrogel based on cholesterol-modified pullulan, and a NanoClip-FD gel was prepared by freeze-drying the nanogel. 7 mm in length was created in the abdominal wall of NOG/SCID mice as a mouse gastroschisis model. Matrigel or NanoCliP-FD gel seeded with dMBs was placed on the biosheet and implanted on the model mice. RESULTS: Fourteen days after surgery, dMBs with Matrigel showed a small amount of coarse aggregations of muscle-like cells. In contrast, dMBs with NanoCliP-FD gel showed multinucleated muscle-like cells, which were expressed as desmin and myogenin by fluorescent immunostaining. CONCLUSION: Nanogels have a porous structure and are useful as scaffolds for tissue regeneration by supplying oxygen and nutrients supply to the cells. Combining dMBs and nanogels on the biosheets resulted in the differentiation and engraftment of skeletal muscle, suggesting the possibility of developing skeletal muscle sheets derived from autologous cells and tissues.

Long-Term Outcomes of Infantile Sacrococcygeal Teratoma: Results from a Multi-Institutional Retrospective Observational Study in Japan.

BACKGROUND: Tumor recurrence, anorectal and urinary dysfunction, and lower limb dysfunction after surgery are observed in infantile sacrococcygeal teratoma (SCT). In this paper, a multi-institutional retrospective observational study was conducted to clarify the long-term functional prognosis in Japan. METHODS: This study was conducted using a paper-based questionnaire distributed to 192 facilities accredited by the Japanese Society of Pediatric Surgeons, covering patients who underwent radical surgery at less than 1 year old and who survived for at least 180 days after birth from 2000 to 2019. RESULTS: A total of 355 patients were included in this analysis. Altman type was I-II in 248 and type III-IV in 107, and the median maximum tumor diameter was 6.1 (range: 0.6-36.0) cm. There were 269 mature teratomas, 69 immature teratomas, and 10 malignant tumors. Total resection was performed in 325, subtotal or partial resection in 27, and surgical complications were noted in 54. The median postoperative follow-up was 6.6 (0.5-21.7) years. Eighty-three patients (23.4 %) had functional sequelae, including 62 (17.5 %) with anorectal dysfunction, 56 (13.0 %) with urinary dysfunction, and 15 (4.2 %) with lower limb motor dysfunction. Recurrence occurred in 42 (11.8 %) at a median age of 16.8 (1.7-145.1) months old. Risk factors for dysfunction included preterm delivery, a large tumor diameter, Altman type III-IV, incomplete resection, and surgical complications. Risk factors for recurrence included immature teratoma or malignancy, incomplete resection, and surgical complications. CONCLUSIONS: Postoperative dysfunction was not low at 23.4 %, and 11.8 % of the patients experienced recurrence occurring more than 10 years after surgery, suggesting the need for periodic imaging and tumor markers evaluations in patients with risk factors. It is necessary to establish treatment guidelines for best practice monitoring of the long-term quality of life. LEVEL OF EVIDENCE: Level II Retrospective Study.

Cholangiolocellular carcinoma with rapid progression initially showing abnormally elevated serum alfa-fetoprotein.

Cholangiolocellular carcinoma (CoCC) is a rare malignant liver tumor derived from hepatic progenitor cells, which exist in the canals of Hering. We encountered a case of CoCC with an extremely poor clinical course, initially showing abnormally elevated serum alfa-fetoprotein (AFP). A 72-year-old male presented with a liver tumor and abnormally elevated serum AFP levels (16,399 ng/ml). We preoperatively diagnosed hepatocellular carcinoma and performed extended right hepatectomy, after which the serum AFP levels remarkably decreased to 97 ng/ml. Postoperatively, the disease was pathologically diagnosed as CoCC. Furthermore, immunohistochemical pathological findings were alcian blue negative, cytokeratin (CK) 7 partially positive, CK19 positive, hepatocyte paraffin-1 negative, membranous negative for epithelial membrane antigen, and AFP negative. Fifty-five days later, intra- and extrahepatic recurrence developed, and the patient died 65 days after surgery. Although CoCCs show favorable outcomes, these characteristics of our case were not previously reported. It is necessary to accumulate more information on CoCC.