A Samoan Hebeloma with phylogenetic ties to the western Pacific

Hebeloma ifeleletorum is described as a new species from American Samoa. Based on analyses of ITS and combined nLSU-ITS datasets H. ifeleletorum clusters with but is distinct from described species that have been placed in the genus Anamika by some. The phylogenetic relationship of H. ifeleletorum to the genus Anamika from Asia and to other species from Australia and New Caledonia suggests that H. ifeleletorum has origins in the western Pacific

Consensus classification of posterior cortical atrophy

INTRODUCTION: A classification framework for posterior cortical atrophy (PCA) is proposed to improve the uniformity of definition of the syndrome in a variety of research settings. METHODS: Consensus statements about PCA were developed through a detailed literature review, the formation of an international multidisciplinary working party which convened on four occasions, and a Web-based quantitative survey regarding symptom frequency and the conceptualization of PCA. RESULTS: A three-level classification framework for PCA is described comprising both syndrome- and disease-level descriptions. Classification level 1 (PCA) defines the core clinical, cognitive, and neuroimaging features and exclusion criteria of the clinico-radiological syndrome. Classification level 2 (PCA-pure, PCA-plus) establishes whether, in addition to the core PCA syndrome, the core features of any other neurodegenerative syndromes are present. Classification level 3 (PCA attributable to AD [PCA-AD], Lewy body disease [PCA-LBD], corticobasal degeneration [PCA-CBD], prion disease [PCA-prion]) provides a more formal determination of the underlying cause of the PCA syndrome, based on available pathophysiological biomarker evidence. The issue of additional syndrome-level descriptors is discussed in relation to the challenges of defining stages of syndrome severity and characterizing phenotypic heterogeneity within the PCA spectrum. DISCUSSION: There was strong agreement regarding the definition of the core clinico-radiological syndrome, meaning that the current consensus statement should be regarded as a refinement, development, and extension of previous single-center PCA criteria rather than any wholesale alteration or redescription of the syndrome. The framework and terminology may facilitate the interpretation of research data across studies, be applicable across a broad range of research scenarios (e.g., behavioral interventions, pharmacological trials), and provide a foundation for future collaborative work

The Effects of Silvicultural Treatments on Occurrence of Mycorrhizal Sporocarps in a Pinus contorta Forest: A Preliminary Study

A preliminary survey was conducted to evaluate the effects of thinning and clearcutting, followed by replanting, on mycorrhizal fungi. A total of 48 species of mycorrhizal fungi was recorded for the study site. Suillus brevipes and S. tomentosus were the dominant species. Data from the survey indicate that thinning reduced the total number of species as compared to an undisturbed stand. Some fungi were adversely affected by thinning while others were positively affected. Members of the Hygrophoraceae appeared to be most susceptible to mild disturbance such as thinning. While clearcutting had a negative impact on the total number of sporocarps of mycorrhizal fungi, Suillus brevipes increased in percent abundance as severity of disturbance increased

Solubilization and Mineralization of Lignin by White Rot Fungi

The white rot fungi Lentinula edodes, Phanerochaete chrysosporium, Pleurotus sajor-caju, Flammulina velutipes, and Schizophyllum commune were grown in liquid media containing (14)C-lignin-labelled wood, and the formation of water-soluble (14)C-labelled products and (14)CO(2), the growth of the fungi, and the activities of extracellular lignin peroxidase, manganese peroxidase, and laccase were measured. Conditions that affect the rate of lignin degradation were imposed, and both long-term (0- to 16-day) and short-term (0- to 72-h) effects on the production of the two types of product and on the activities of the enzymes were monitored. The production of (14)CO(2)-labelled products from the aqueous ones was also investigated. The short-term studies showed that the different conditions had different effects on the production of the two products and on the activities of the enzymes. Nitrogen sources inhibited the production of both products by all species when differences in growth could be discounted. Medium pH and manganese affected lignin degradation by the different species differently. With P. chrysosporium, the results were consistent, with lignin peroxidase playing a role in lignin solubilization and manganese peroxidase being important in subsequent CO(2) production