Successful treatment of a pancreatic schwannoma by spleen-preserving distal pancreatectomy

Schwannomas are neurogenic tumors that arise from the neural sheaths of peripheral nerves.These tumors can be located in any area of the human body;the most common locations are the head,neck,trunk and extremities.Pancreatic schwannomas are very rare.Over the past 40 years,only 67 cases of pancreatic schwannomas have been reported in the English literature.Here we present a case of pancreatic schwannoma in a 62-year-old male.The tumor was revealed by ultrasound and computed tomography in the neck and body of the pancreas.An accurate diagnosis was difficult to obtain preoperatively.The patient consented to the performance of a laparotomy,and the mass was found in the neck and body of the pancreas and successfully treated using a spleenpreserving distal pancreatectomy with splenic artery and vein preservation.The procedure has only been reported in one other case of pancreatic schwannoma;here we present the second reported case.Macroscopically,the tumor was well circumscribed,gray-white in color and3.3 cm×2.8 cm in size.Microscopically,the tumor cells were spindle-shaped and had a palisading arrangement with no atypia,which are results compatible with a benign tumor.Both hypercellular and hypocellular areas were visible.Immunohistochemically,the tumor cells were strongly positive for S-100 protein.The tumor was definitively diagnosed as a schwannoma of the pancreatic neck and body.The patient was followed for 72 mo and has been doing well without any complications.

Successful treatment of a giant ossified benign mesenteric schwannoma

Primary benign schwannoma of the mesentery is extremely rare. To date, only 9 cases have been reported in the English literature, while mesenteric schwannoma with ossified degeneration has not been reported thus far. In the present study, we present the first giant ossified benign mesenteric schwannoma in a 58-year-old female. Ultrasound, computed tomography and magnetic resonance imaging were used, but it was still difficult to determine the definitive location and diagnose the mass. By laparotomy, a 10.0 cm × 9.0 cm × 9.0 cm giant mass was found in the mesentery and was then completely resected. Microscopically, the tumour located in the mesentery mainly consisted of spindleshaped cells with a palisading arrangement. Some areas of the tumour were ossified, and a true metaplastic bone formation was observed, with the presence of bone lamellae and osteoblasts. Immunohistochemical investigation of the tumour located in the mesentery showed that the staining for the S-100 protein was strongly positive, while the stainings of SMA, CD34, CD117 and DOG-1 were negative. The cell proliferation index, measured with Ki67 staining, was less than 3%. Finally, a giant ossified benign mesenteric schwannoma was diagnosed. After surgery, the patient was followed up for a period of 43 mo, during which she remained well, with no evidence of tumour recurrence.

High crystalline quality of SiGe fin fabrication with Si-rich composition area using replacement fin processing

A high crystalline quality of SiGe fin with an Si-rich composition area using the replacement fin processing is systematically demonstrated in this paper.The fin replacement process based on a standard FinFET process is developed.A width of less than 20-nm SiGe fin without obvious defect impact both in the direction across the fin and in the direction along the fin is verified by using the high angle annular dark field scanning transmission electron microscopy and the scanning moiréfringe imaging technique.Moreover,the SiGe composition is inhomogenous in the width of the fin.This is induced by the formation of 111 facets.Due to the atomic density of the 111 facets being higher,the epitaxial growth in the direction perpendicular to these facets is slower than in the direction perpendicular to 001.The Ge incorporation is then higher on the 111 facets than on the 001 facets.So,an Si-rich area is observed in the central area and on the bottom of SiGe fin.

Expression of Cytokeratin,Actin and Endocrine Hormones in Human Hatched Blastocyst Implantation Model in vitro

Objective To investigate the expression of cytokeratin,actin and hCG,E2 and P of human hacthed blastocysts in the model.Methods Human hatched blastocysts were co-cultured with human endometrial decidualization stromal cell monolayer.The process of orientation,attachment,outgrowth and invasion in morphology were observed.Immunofluorescence staining for cytokeratin and actin,immunofluorescence measurement of hCG and radioimmunoassay measurement of E2 and P were performed.Results Blastocysts attached to stromal cell layer after 5h in co-culture.After 24h in co-culture,the trophoblast protruded from two opposite poles of the blastocyst and underwent outgrowth into the stromal cell monolayer,blastocyst became bigger and invaded finally into the stromal cells.After 48h in co-culture,cytokeratin staining was only visible in trophoblast but not stromal cells,actin staining was visible in both of trophoblast and stromal cells with distinct conformation and structure.Stromal cells had prominent linear actin filaments,aligned along the long axis of the cells.Cytokeratin staining in trophoblast cells was localized in short filaments arranged in a mesh.hCG,E2 and P levels in the supernate of stromal cell-blastocyst co-culture were higher than the supernate from blastocyst cultured only （P〈0.01）.Conclusion An implantation model for the reflection of the process of human blastocysts attachment,outgrowth and invasion into stromal cells has been established in vitro.Cytokeratin,actin and hCG,E2 and P take place corresponding changes in the human implantation blastocyst cells.