ABSTRACT
High-throughput fluorescence polarization immunoassays (FPIAs) for mycotoxin were conducted using a portable FP analyzer with a microdevice. Simultaneous FPIA measurements for 8 different deoxynivalenol (DON) concentrations in 12 chambers (total of 96 samples) and high-throughput FPIA measurements for single DON concentrations in more than 500 chambers were conducted. The results indicated that simultaneous FPIAs for 96 independent samples and for 500 samples were possible by FP imaging. The FP analyzer has a size of 65 cm (W 35 cm × D 15 cm × H 15 cm) and costs less than $5000. The sample volume was 1 nL. Furthermore, it is expected that sample reaction and FP detection can be automatically conducted with the analyzer by changing the microdevice and the software. Its features such as low cost and portability will contribute to on-site measurement and point-of-care testing. Additionally, the high-throughput feature will contribute to the study of molecular interactions based on FP measurements.
ABSTRACT
Fluorescence polarization (FP) offers easy operation and rapid processing, making it implementable in molecular interaction analysis. Previously we have developed a unique FP measurement system using a liquid crystal (LC) layer and an image sensor. The system is based on a principle of synchronized detection between the switching rate of the LC layer and the sampling rate of the CCD. The FP system realized simultaneous multiple sample detection; however, the measurement precision was lower than that of the conventional FP apparatus. The main drawbacks were low light transmittance of the LC layer and insufficient synchronization between the LC layer and CCD. In this paper, we developed a new FP analyzer based on LC-CCD synchronization detection. By using a newly designed LC with high transmittance and improving synchronization, the performance of the system has been dramatically improved. Additionally, we reduced the cost by using an inexpensive CCD and an LED as the excitation source. Simultaneous FP immunoassay of multiple samples of prostaglandin E2 was performed. The error rate of the FP system is reduced from 16.9% to 3.9%, as comparable to the commercial conventional FP system.
ABSTRACT
A case of recurrent pancreatic cancer effectively responded to S-1 and irinotecan combined with third-line chemotherapy (IRIS) with PSK. The patient was a 75-year-old female. In October 2007, a pancreatoduodenectomy was performed, followed with 6 courses of systemic adjuvant chemotherapy of gemcitabine (GEM). Three months after finishing the adjuvant chemotherapy, a recurrence of para-aortic lymph node metastasis was confirmed. We resumed the second-line chemotherapy of S-1/GEM (GS) with PSK. GS therapy was continued for about 3 years, until the recurrent lesion was found to have increased after 30 courses. Nevertheless, we continued up to 39 courses. In November 2011, we started third-line chemotherapy using S-1/irinotecan (IRIS) with PSK. The regimen was S-1 of 80 mg/body/day, continuously administered for day 1-14th, followed by a discontinuation for 2 weeks. CPT-11 100 mg/body/day was administered on day 1 and 15th; and PSK of 3 g/ body/day was continued, until it resulted in increased recurrent lesions. After the end of 4 courses, recurrent lesions started to respond partially. Currently, the patient is being treated as an outpatient. This case indicates that IRIS (S-1/CPT-11) is an effective therapy when pancreatic cancer fails to respond to GS therapy.
