Rediscovery of Roesleria subterranea from Japan with a discussion of its infraspecific relationships detected using molecular analysis

Roesleria subterranea, a distinctive hypogeous fungus, was collected from unidentified deciduous plant roots in red pine forests. The fungus had been documented several times in the past in Japan, but with no description. A description is given here based on specimens collected in Japan. The sequence of the D1-D2 region of the 28S rDNA obtained from the isolate was identical to those of the European and American specimens. Maximum parsimony analysis incorporating the present data and all other available ITS-5.8S sequences for R. subterranea showed that there are two infraspecific groups. One of them, composed of the isolates from Vitis spp. in Germany, Italy, and USA, was monophyletic. The other group, composed of isolates from deciduous trees in various countries, including Japan, was paraphyletic. The phylogenetic patterns indicate that the host may be more important than geographical distance for the genetic diversification of R. subterranea

Rediscovery of Roesleria subterranea from Japan with a discussion of its infraspecific relationships detected using molecular analysis

Roesleria subterranea, a distinctive hypogeous fungus, was collected from unidentified deciduous plant roots in red pine forests. The fungus had been documented several times in the past in Japan, but with no description. A description is given here based on specimens collected in Japan. The sequence of the D1-D2 region of the 28S rDNA obtained from the isolate was identical to those of the European and American specimens. Maximum parsimony analysis incorporating the present data and all other available ITS-5.8S sequences for R. subterranea showed that there are two infraspecific groups. One of them, composed of the isolates from Vitis spp. in Germany, Italy, and USA, was monophyletic. The other group, composed of isolates from deciduous trees in various countries, including Japan, was paraphyletic. The phylogenetic patterns indicate that the host may be more important than geographical distance for the genetic diversification of R. subterranea

Machine learning-based prediction of conversion coefficients for I-123 metaiodobenzylguanidine heart-to-mediastinum ratio

Purpose: We developed a method of standardizing the heart-to-mediastinal ratio in 123I-labeled meta-iodobenzylguanidine (MIBG) images using a conversion coefficient derived from a dedicated phantom. This study aimed to create a machine-learning (ML) model to estimate conversion coefficients without using a phantom. Methods: 210 Monte Carlo (MC) simulations of 123I-MIBG images to obtain conversion coefficients using collimators that differed in terms of hole diameter, septal thickness, and length. Simulated conversion coefficients and collimator parameters were prepared as training datasets, then a gradient-boosting ML was trained to estimate conversion coefficients from collimator parameters. Conversion coefficients derived by ML were compared with those that were MC simulated and experimentally derived from 613 phantom images. Results: Conversion coefficients were superior when estimated by ML compared with the classical multiple linear regression model (root mean square deviations: 0.021 and 0.059, respectively). The experimental, MC simulated, and ML-estimated conversion coefficients agreed, being, respectively, 0.54, 0.55, and 0.55 for the low-; 0.74, 0.70, and 0.72 for the low-middle; and 0.88, 0.88, and 0.88 for the medium-energy collimators. Conclusions: The ML model estimated conversion coefficients without the need for phantom experiments. This means that conversion coefficients were comparable when estimated based on collimator parameters and on experiments

Mandibular vascular hamartoma in a cat

A 10-year-old cat presented for evaluation with a 1-month history of salivation and oral bleeding. A right mandibular mass was palpated and computed tomography examination revealed entire bone proliferation. Mandibular bone biopsy was performed, and histopathological diagnosis was vascular hamartoma. The cat suddenly died on day 140