RETROPERITONEAL SCHWANNOMA : A CASE REPORT AND REVIEW OF THE LITERATURE

Reported herein is a rare case of retroperitoneal schwannoma in a patient without von Recklinghausen's disease. This patient was free of symptoms, and the tumor was found by chance during a periodical physical examination. Complete excision of the tumor was performed, and as of this writing, 36 months after the operation, the patient is free of the disease. In addition, a review was carried out on the 121 cases of retroperitoneal schwannoma reported in the Japanese literature from 1981 to 1992. In this series, malignant tumors were seen in 26.4% of all cases, and when this tumor was found in association with von Recklinghausen's disease, the malignancy rate increased to 52.9%. Thirty seven percent of the patients with malignant tumors had died at the time of writing of their case report, and their mean survival period was 18 months after the first surgical treatment. All the patients with benign tumors underwent complete resection and had a good prognosis

Effluent Markers Related to Epithelial Mesenchymal Transition with Adjusted Values for Effluent Cancer Antigen 125 in Peritoneal Dialysis Patients

Objectives. Epithelial mesenchymal transition (EMT) is important for peritoneal deterioration. We evaluated the association between peritoneal solute transport rate (PSTR) and effluent markers related to EMT with adjusted values for effluent cancer antigen 125 (CA125). Methods. One hundred five incident peritoneal dialysis (PD) patients on PD for 25 (12–68) months with biocompatible solutions were included in the study. Fast peritoneal equilibration test was used to evaluate PSTR. Effluent hepatocyte growth factor (HGF), bone morphogenic protein-7 (BMP-7), vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), and CA125 at 4 h were measured. Results. Patients with dialysate/plasma creatinine ≧0.82 showed significantly higher effluent HGF (240 versus 133 pg/mL, P < .001), VEGF, IL-6, and IL6/CA125 levels than the others but no significant differences in effluent HGF/CA125, BMP-7, and BMP7/CA125 were observed. Conclusion. Increase in the effluent HGF levels as a compensatory mechanism is a marker of peritoneal deterioration, but controversy remains regarding adjusted value for CA125

IEEE TRANSACTION ON ELECTRON DEVICES

The modern power electronics era started with the commercialization of the silicon controlled rectifier (SCR) in 1957, since when power electronics systems have been installed in a wide range of applications from appliances to traction and utility systems as the technology has advanced. Meanwhile, simulation tools have played an important role in the research and development of power semiconductors and power electronics systems. As power devices and power electronics become increasingly important technologies in today’s electric society, it is worth examining the overall integration of power electronics design. This paper reviews the history of simulation technology with reference to power device modeling and discusses the future of power electronics system design

HVDC system for a data center equipped with SiC power devices

SiC power devices have attracted attention as the next-generation semiconductor devices that surpass silicon devices. The SiC has some superior physical properties when compared with the conventional silicon, and is expected to operate with lower on-resistance and under higher temperature. Furthermore the SiC device has higher thermal conductivity and then has the prominent feature of heat dissipation. Among many expected applications of SiC, this paper presents the application to the power supply system for the information and communication system such as a data center. Firstly, the development of a high power-density technology for a 5-kW isolated DC-DC converter using a hybrid-pair of Si-MOSFET and SiC-SBD is reported. Secondly, a new type DC circuit breaker using SiC-SIT is introduced