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Contains fulltext : 240224.pdf (Publisher’s version ) (Open Access) 29 januari 2021

Contains fulltext : 236351.pdf (Publisher’s version ) (Open Access)

Contains fulltext : 229020.pdf (Publisher’s version ) (Open Access)

The aeroterrestrial, unicellular green alga Spongiochrysis hawaiiensis had been included in the ulvophycean order Cladophorales based on small subunit (SSU) rDNA sequence data, and represents so far the only fully terrestrial member of this order. Other characteristics of S.?hawaiiensis that are atypical for Cladophorales include the presence of large amounts of carotenoids and a budding-like mode of cell division. As the position of this terrestrial, unicellular alga in an order of aquatic, multicellular green algae is unusual, we re-evaluated the phylogenetic relationships of this enigmatic organism based on supplementary SSU rDNA sequences as well as novel large ribosomal subunit (LSU) rDNA and internal transcribed spacer (ITS rDNA) sequences. Additionally, we examined several morphological characters of S.?hawaiiensis, as well as low molecular weight carbohydrate (LMWC) patterns of S.?hawaiiensis and members of the Cladophorales and Trentepohliales as potential chemotaxonomic markers. We found S.?hawaiiensis to be uninucleate. The analysis of the LMWC content detected the presence of the polyol erythritol in S.?hawaiiensis and in the Trentepohliales, while this compound was missing in the Cladophorales. The phylogenetic analyses of the novel sequences placed S.?hawaiiensis in the terrestrial Trentepohliales. This placement is supported by the aeroterrestrial habitat, the presence of large amounts of carotenoids, the uninucleate cells, and the presence of the polyol erythritol as a protective compound against water loss.

Plattenepithelkarzinome von Zunge, Zungengrund sowie Mundboden zeichnen sich nicht selten durch ein tief submuköses Wachstum aus. Trotz möglicherweise eindeutiger Befunde in der Bildgebung kann sich die für die Diagnosesicherung und Therapieplanung essentielle Histologie-Gewinnung mitunter[for full text, please go to the a.m. URL], 84. Jahresversammlung der Deutschen Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie

The Aegagropila clade represents a unique group of cladophoralean green algae occurring mainly in brackish and freshwater environments. The clade is sister to the species-rich and primarily marine Cladophora and Siphonocladus lineages. Phylogenetic analyses of partial LSU and SSU nrDNA sequences reveal four main lineages within the Aegagropila clade, and allow a taxonomic reassessment. One lineage consists of two marine ‘Cladophora’ species, for which the new genus Pseudocladophora and the new family Pseudocladophoraceae are proposed. For the other lineages, the family name Pithophoraceae is reinstated. Within the Pithophoraceae, the earliest diverging lineage includes Wittrockiella and Cladophorella calcicola, occurring mainly in brackish and subaerial habitats. The two other lineages are restricted to freshwater. One of them shows a strong tendency for epizoism, and consists of Basicladia species and Arnoldiella conchophila. The other lineage includes Aegagropila, Pithophora and a small number of tropical ‘Cladophora’ species. The latter are transferred to the new genus Aegagropilopsis. Previously, polypyramidal pyrenoids had been suggested to be apomorphous for this clade, but we report the finding of both polypyramidal and bilenticular pyrenoids in members of the Pithophoraceae, and thus show that this character has no diagnostic value.

The Aegagropila-clade is a unique lineage of algae within the large order Cladophorales and consists of poorly known taxa that mainly occur in brackish and freshwater environments. The clade is sister to the species-rich, primarily marine Cladophora- and Siphonocladus-lineages. Most of its members occur in narrow niches such as on the carapaces of freshwater turtles (some members of Basicladia), on freshwater snails and bivalves (monotypic Arnoldiella and several Basicladia species), on and endophytically in saltmarsh plants and mangrove pneumatophores (some members of Wittrockiella), or on marine intertidal snails (Cladophora conchopheria). Aegagropila linnaei is the best known representative of the lineage and has gained considerable scientific, cultural and economic fame due to the peculiar lake balls formed under specific conditions. The confused taxonomy of the Aegagropila-clade was clarified using methods of molecular phylogenetic inference, resulting in the re-instatement of the Pithophoraceae, descriptions of two new genera and several nomenclatural changes. Phylogenetic analyses led to an understanding of the evolution of the heterotrichous habit as an adaptation to changeable environmental conditions. In selected taxa, topics such as phylogeography and dispersal abilities, historical biogeography and glacial refugia, and ecology and declining populations were studied in detail.

Aim:Aegagropila linnaei is a freshwater macroalga that is generally regarded as a rare species. It is apparently absent from large but seemingly suitable areas of the Northern Hemisphere, implying a limited dispersal potential and an imprint of Pleistocene glaciations in its biogeography. However, despite the popularity of its enigmatic lake ball-form, detailed biogeographical studies of A. linnaei have never been conducted. The main means of reproduction of A. linnaei is fragmentation and akinetes are not formed, supporting the assumption of limited dispersal capacity. The aim of this study was to reconstruct the biogeography of A. linnaei, and to identify possible refugia during glaciations, as well as to evaluate dispersal potential by quantitative desiccation experiments. Location: Palaearctic. Methods: The current distribution of A. linnaei was inferred from herbarium specimens, literature data and recent field observations. All herbarium specimens were morphologically re-examined. Desiccation experiments were performed with vegetative filaments of three isolates of A. linnaei, as no specialized resistant stages are known. For comparison, the widespread freshwater algae Cladophora glomerata and Rhizoclonium sp. were included. Internal transcribed spacer (ITS) ribosomal DNA sequences were generated and a ribotype network was constructed. Results:Aegagropila linnaei was recorded from 283 locations in freshwater and brackish environments. The majority of locations were in central and northern Europe in previously glaciated areas. Desiccation experiments showed that A. linnaei is very susceptible to desiccation. Based on ITS sequences of 34 samples, five different ribotypes were identified. Four of these ribotypes had a restricted distribution. Aegagropila linnaei represents a single species with little genetic variation (0.1–0.5%). Main conclusions This is the most comprehensive study of this species so far, reporting many new locations and tackling several taxonomic problems. Few additional finds were made from North America, and the origin of A. linnaei is inferred to be in Asia. The highest density of its present-day locations is in previously glaciated areas in Europe, where glacial ice-dammed lakes might have functioned as refugia. Low effective long-distance dispersal capacity is inferred, based on high susceptibility to desiccation and its modes of dispersal.

Introduction Inverted Papilloma (IP) is a primary benign but locally aggressive epithelial sinonasal lesion. Etiology of IP is still unknown [ref:15]. This tumour is also known as Schneiderian papilloma, because of the fact that nearly all cases of IP derive from the Schneiderian mucosa[for full text, please go to the a.m. URL], ESBS 2005: Skull Base Surgery: An Interdisciplinary Challenge; 7th Congress of the European Skull Base Society held in association with the 13th Congress of the German Society of Skull Base Surgery

The microfilamentous green alga Uronema curvatum is widely distributed along the western and eastern coasts of the north Atlantic Ocean where it typically grows on crustose red algae and on haptera of kelps in subtidal habitats. The placement of this marine species in a genus of freshwater Chlorophyceae had been questioned. Molecular phylogenetic analysis of nuclear-encoded small and large subunit rDNA sequences reveal that U. curvatum is closely related to the ulvophycean order Cladophorales, with which it shares a number of morphological features, including a siphonocladous level of organization and zoidangial development. The divergent phylogenetic position of U. curvatum, sister to the rest of the Cladophorales, along with a combination of distinctive morphological features, such as the absence of pyrenoids, the diminutive size of the unbranched filaments and the discoid holdfast, warrants the recognition of a separate genus, Okellya, within a new family of Cladophorales, Okellyaceae. The epiphytic Urospora microscopica from Norway, which has been allied with U. curvatum, is revealed as a member of the cladophoralean genus Chaetomorpha and is herein transferred to that genus as C. norvegica nom. nov.