ABSTRACT
The solidification behavior of poly(vinylidene fluoride) (PVDF) solution during membrane preparation by thermally induced phase separation (TIPS) was investigated. Apparatus newly developed in our laboratory was used to quantitatively measure membrane stiffness during phase separation. In this apparatus, a cooling polymer solution, placed on a stage, is moved upwards and the surface of the polymer solution contacts a sphere attached to the tip of a needle. The displacement of a blade spring attached to the needle is then measured by a laser displacement sensor. Different phase separation modes, such as liquid-liquid (L-L) phase separation and solid-liquid (S-L) phase separation (polymer crystallization) were investigated. In the case of S-L phase separation, the stiffness of the solution surface began to increase significantly just before termination of crystallization. In contrast, L-L phase separation delayed solidification of the solution. This was because mutual contact of the spherulites was obstructed by droplets of polymer-lean phase formed during L-L phase separation. Thus, the solidification rate was slower for the L-L phase separation system than for the S-L phase separation system.
ABSTRACT
BACKGROUND: Olfactory neuroblastoma is a rare malignant neoplasm of the nasal cavity and of the paranasal sinus. In the treatment of patients with advanced olfactory neuroblastoma, the combination of craniofacial resection with radiotherapy and/or chemotherapy has significantly improved the survival rate. However, locoregional recurrence and distant metastasis frequently occur, irrespective of the aggressiveness of therapy. We report our experience on the outcomes of olfactory neuroblastoma in patients treated with concurrent chemoradiotherapy (CCRT). PATIENTS AND METHODS: We retrospectively analyzed the cases of seven patients with olfactory neuroblastoma, treated in the past 15 years. Six patients were treated with CCRT, consisting of cisplatin (60 mg/m(2), day 4), 5-fluorouracil (600 mg/m(2), given over 24 h for 5 days, days 1-5), methotrexate (30 mg/m(2), day 1) and leucovorin (20 mg/m(2), days 1-5) (PFML). One patient was treated with radiotherapy and neoadjuvant chemotherapy, which consisted of a combination of three drugs: cyclophosphamide (360 mg/m(2), day 1), cisplatin (60 mg/m(2), day 4), 5-fluorouracil (600 mg/m(2), given over 24 h for 5 days, days 1-5) (PFC). Salvage surgery was performed in the primary remaining site. RESULTS: The overall 5-year survival rates were 3/6 for patients treated with CCRT using PFML and 2/5 for patients with Kadish stage C olfactory neuroblastoma. The locoregional response rate was 4/6. CONCLUSION: In our limited experience, CCRT with PFML had therapeutic efficacy as a primary treatment, while surgical treatment and postoperative radiotherapy have been the main treatment modalities.
