Microwave Inter-Connections and Switching by means of Carbon Nano-tubes

In this work, carbon nanotube (CNT) based interconnections and switches will be reviewed, discussing the possibility to use nanotubes as potential building blocks for signal routing in microwave networks. In particular, theoretical design of coplanar waveguide (CPW), micro‐strip single‐pole‐single‐throw (SPST) and single‐pole‐double‐throw (SPDT) devices has been performed to predict the electrical performances of CNT‐based RF switching configurations. Actually, by using the semiconductor‐conductor transition obtained by properly biasing the CNTs, an isolation better than 30 dB can be obtained between the ON and OFF states of the switch for very wide bandwidth applications. This happens owing to the shape deformation and consequent change in the band‐gap due to the external pressure caused by the electric field. State‐of‐art for other switching techniques based on CNTs and their use for RF nano‐interconnections is also discussed, together with current issues in measurement techniques

MDM2 is a novel E3 ligase for HIV-1 Vif

The human immunodeficiency virus type 1 (HIV-1) Vif plays a crucial role in the viral life cycle by antagonizing a host restriction factor APOBEC3G (A3G). Vif interacts with A3G and induces its polyubiquitination and subsequent degradation via the formation of active ubiquitin ligase (E3) complex with Cullin5-ElonginB/C. Although Vif itself is also ubiquitinated and degraded rapidly in infected cells, precise roles and mechanisms of Vif ubiquitination are largely unknown. Here we report that MDM2, known as an E3 ligase for p53, is a novel E3 ligase for Vif and induces polyubiquitination and degradation of Vif. We also show the mechanisms by which MDM2 only targets Vif, but not A3G that binds to Vif. MDM2 reduces cellular Vif levels and reversely increases A3G levels, because the interaction between MDM2 and Vif precludes A3G from binding to Vif. Furthermore, we demonstrate that MDM2 negatively regulates HIV-1 replication in non-permissive target cells through Vif degradation. These data suggest that MDM2 is a regulator of HIV-1 replication and might be a novel therapeutic target for anti-HIV-1 drug

Current status of tertiary debulking surgery and prognosis after secondary debulking surgery for recurrent Müllerian epithelial cancer in Japan: a retrospective analysis of 164 patients (KCOG-G1402)

BackgroundThis study aimed to evaluate the current status of secondary debulking surgery (SDS) and tertiary debulking surgery (TDS; performed for recurrence after SDS) and to assess the overall survival after recurrence of Müllerian epithelial cancer in Japan. We also evaluated the data of patients who underwent a fourth debulking surgery (i.e., quaternary debulking surgery (QDS)).MethodsWe conducted a retrospective study of 164 patients with recurrent Müllerian epithelial cancers (i.e., ovarian, tubal, and peritoneal cancers). The SDS was performed between January 2000 and September 2014 in 20 Japanese hospitals. Clinicopathological data were collected and analyzed.ResultsOf the 164 patients, 66 patients did not have a recurrence or died after SDS. Ninety-eight patients had a recurrence after SDS. Forty-three of the 98 patients underwent TDS; 55 of the 98 patients did not undergo TDS and were classified into the non-TDS group. The overall survival (OS) after SDS was significantly better in the TDS group than in the non-TDS group. The median OS after SDS was 123 and 42 months in the TDS group and non-TDS group, respectively. Of the 43 patients who received TDS, 11 patients were further treated with QDS. The median OS after SDS was 123 months for patients who underwent QDS.ConclusionsThis multicenter study on the prognosis of post-SDS is apparently the first report on QDS in Japan. Patients undergoing TDS have a good prognosis, compared to patients in the non-TDS group. Novel drugs are being evaluated; however, debulking surgery remains a necessary treatment for recurrence

Successful resection of growing teratoma syndrome in the abdominal wall with reconstruction using tensor fascia lata muscle flap: A case report and literature review

While cancer cure is the primary goal, fertility preservation is also a cornerstone of the underlying principle of treatment for ovarian germ cell tumors. Growing teratoma syndrome (GTS) presents with growth of mature teratomas during or after chemotherapy. We report a case of successful treatment of GTS in the anterior abdominal wall involving reconstruction. A 23-year-old woman with a suspected right ovarian mature teratoma with torsion underwent emergency laparoscopically assisted extracorporeal ovarian cystectomy. Histopathological findings revealed a grade 1 immature teratoma. After two months, postoperative α-fetoprotein (AFP) levels increased, and disseminated lesions developed not only in the pelvic cavity but also in the abdominal wound where the tumor had been extracted using an extracorporeal technique at the time of primary surgery. The patient underwent laparoscopic right salpingo-oophorectomy, excision of multiple peritoneal nodules, and biopsy of abdominal wall mass. The left rectus abdominis muscle tumor could not be removed. All of these nodules were diagnosed as metastatic immature teratomas. Although the patient received three cycles of chemotherapy, the residual tumor in the abdominal wall grew remarkably despite post-chemotherapy normalization of AFP levels. Both rectus abdominis muscles involving the residual tumors were removed and reconstructed using a left tensor fascia lata muscle flap. Histopathologically, the residual tumors were identified as mature teratomas with no immature elements, resulting in GTS. The patient got pregnant without the need of fertility treatment and gave birth uneventfully by cesarean section. Thus, reconstruction with a tensor fascia lata muscle flap facilitated complete removal of GTS while preserving fertility