For elucidation of the taxonomic status of the Japanese Fasciola species, whole mitochondrial DNA of Fasciola hepatica from Australia, F. gigantica from Malaysia, and Fasciola sp. from Japan was digested with three four-base-cutting endonucleases: HinfI, MspI, and RsaI. The resulting digestion patterns showed that for each enzyme there were some bands specific for each geographical isolate and that the Japanese Fasciola sp. shared more bands with F. gigantica than with F. hepatica. Nucleotide sequences of two regions, the second internal transcribed spacer (ITS2) of the nuclear ribosomal RNA cluster and mitochondrial cytochrome c oxidase subunit I (COI), were also compared among them. The ITS2 sequence was highly conserved among the three isolates. F. gigantica and the Japanese Fasciola sp. were identical, but they differed from the Australian F. hepatica at six sites, one of which was a deletion. The COI sequence was less conserved but implied a similar relationship between the isolates. There seems no reason to regard the Japanese Fasciola sp. as anything other than a strain of F. gigantica.
Background and purpose: Several recent randomized controlled trials (RCTs) in non-metastatic castration resistant prostate cancer (nmCRPC) have demonstrated a significant improvement in metastasis-free survival (MFS); however, an improvement in overall survival (OS) is not reported yet. Since the surrogacy of MFS to OS has not been formally investigated in nmCRPC in Japan, this study evaluated the correlation between MFS and OS among a nmCRPC population in Japan. Methods: This is a retrospective longitudinal observational cohort study in patients with nmCRPC using the Japanese Medical Data Vision (MDV) database covering over 20 million patients. A total of 1236 patients with CRPC who had no prior medical history of cancer except prostate cancer and no distant metastasis, and who fulfilled PCWG2 criteria, were identified. Following the identification of nmCRPC, patients' medical records were investigated for subsequent events of metastasis and death. Results: The median follow-up time was 24 months. Median MFS was 28 months (95% CI: 24.0 to 33.0 months) and median OS could not be estimated (95% CI: not estimated). There was a statistically significant correlation between MFS and OS (Pearson's correlation coefficient = 0.62; 95% CI: 0.58-0.65; p