[Accreditation and certification of skull base centres in Germany by the German Society for Skull Base Surgery (Gesellschaft für Schädelbasischirurgie, GSB). German version]

The German Society for Skull Base Surgery (Gesellschaft für Schädelbasischirurgie, GSB) has developed a protocol for the certification of GSB skull base centres. The development of such a protocol has led to numerous open and sometimes controversial discussions among the GSB members. The various critical discussion points will be reviewed and the ensuing results, which will then be included in the accreditation protocol, presented. The current GSB accreditation protocol will be presented and explained in an international comparison.

Sorbicillactone A: a structurally unprecedented bioactive novel-type alkaloid from a sponge-derived fungus

This chapter deals with the discovery of sorbicillactone A, as an illustrative example of the fruitful cooperation within BIOTECmarin--its isolation and chemical characterization, and its biological activities. Sorbicillactone A was isolated from a strain of Penicillium chrysogenum cultured from a sample of the Mediterranean sponge Ircinia fasciculata; it possesses a unique bicyclic lactone structure, seemingly derived from sorbicillin. Among the numerous known sorbicillin-derived structures, it is the first found to contain nitrogen and thus the first representative of a novel type of 'sorbicillin alkaloids', apparently originating from a likewise remarkable biosynthesis. Furthermore, the compound exhibits promising activities in several mammalian and viral test systems, in particular a highly selective cytostatic activity against murine leukemic lymphoblasts (L5178y) and the ability to protect human T cells against the cytopathic effects of HIV-1. These properties qualify sorbicillactone A or one of its derivatives for animal and (hopefully) also future therapeutic human trials.

New natural products from the sponge-derived fungus Aspergillus niger

Fractionation of the EtOAc extract of a static culture of Aspergillus niger isolated from the Mediterranean sponge Axinella damicornis yielded eight secondary metabolites, out of which seven compounds (2-8) proved to be new natural products, whereas one was identified as the known fungal pigment cycloleucomelone (1). The new compounds included the 3,3'-bicoumarin bicoumanigrin (2), the structurally unusual 4-benzyl-1H-pyridin-6-one derivatives aspernigrins A and B (3 and 4), and pyranonigrins A-D (5-8), the latter featuring a novel pyrano[3,2-b]pyrrole skeleton hitherto unprecedented in nature. All structures were elucidated on the basis of extensive one- and two-dimensional NMR spectroscopic studies ((1)H, (13)C, COSY, HMQC, HMBC, NOE difference spectra) and mass spectral analysis. For the two chiral molecules 4 and 5, the absolute configurations were established by quantum chemical calculations of their circular dichroism (CD) spectra. In each case, two independent methods, i.e., a molecular dynamics approach taking into consideration the molecular flexibility, and a conformational analysis followed by Boltzmann weighting of the single CD spectra calculated for the conformers thus obtained, led to identical results without the need of any empirical comparison of chiroptical data reported for reference compounds. Bicoumanigrin (2) showed moderate cytotoxicity against human cancer cell lines in vitro. In addition, aspernigrin B (4) was found to display a strong neuroprotective effect against glutamic acid.

Anthraquinones and betaenone derivatives from the sponge-associated fungus Microsphaeropsis species: novel inhibitors of protein kinases

An undescribed fungus of the genus Microsphaeropsis, isolated from the Mediterranean sponge Aplysina aerophoba, produces two new betaenone derivatives (1, 2) and three new 1,3,6, 8-tetrahydroxyanthraquinone congeners (5-7). The structures of the compounds were established on the basis of NMR spectroscopic and mass spectrometric data and by CD spectroscopy. This is the first report wherein the (1)H and (13)C NMR data of the betaenone congeners are fully and unambiguously assigned on the basis of two-dimensional NMR spectroscopy. Furthermore, we describe the first elucidation of the absolute configuration of 1-(2'-anthraquinonyl)ethanols such as 5 and 6, by quantum chemical calculation of their circular dichroism (CD) and comparison with experimentally measured spectra. Moreover, it was shown that compounds 1, 5, 6, and 7 are inhibitors of PKC-epsilon, CDK4, and EGF receptor tyrosine kinases.

Molecular phylogeny of labyrinthulids and thraustochytrids based on the sequencing of 18S ribosomal RNA gene

Labyrinthulids and thraustochytrids are unicellular heterotrophs, formerly considered as fungi, but presently are recognized as members in the stramenopiles of the kingdom Protista sensu lato. We determined the 18S ribosomal RNA gene sequences of 14 strains from different species of the six genera and analyzed the molecular phylogenetic relationships. The results conflict with the current classification based on morphology, at the genus and species levels. These organisms are separated, based on signature sequences and unique inserted sequences, into two major groups, which were named the labyrinthulid phylogenetic group and the thraustochytrid phylogenetic group. Although these groupings are in disagreement with many conventional taxonomic characters, they correlated better with the sugar composition of the cell wall. Thus, the currently used taxonomic criteria need serious reconsideration.

Ochroconis humicola causing muscular black spot disease of Atlantic salmon (Salmo salar)

A dematiaceous hyphomycete was isolated from black discoloured areas of the somatic musculature of a specimen of Atlantic salmon. The fungus caused an endogenous mycosis and obviously must be classified as a facultative or opportunistic pathogen of marine fish. The optimum temperature for the strain was in the range between 20 and 25 °C, and the temperature tolerance for growth ranged from 10 to almost 37 °C. The morphological and physiological investigation revealed that the pathogen belongs to the genus Ochroconis de Hoog et von Arx, which is synonymous with Scolecobasidium Abbott. However, the definite species identification raised some difficulties, because the characteristics of our pathogenic isolate H 14 670 variably matched with at least four of the known species within the Ochroconis – Scolecobasidium — Dactylaria complex, i.e., O. humicola, O. constrictum, O. gallopavum, and O. simplex. Because of this multispecies affinity and taking into account the actual confused taxonomic state within this group of hyphomycetes, especially with regard to the pathogenic strains, the identification of the present isolate as O. humicola remains with some reservation. Key words: Atlantic salmon (Salmo salar L.), Dactylaria, fish disease, marine fungi, Ochroconis humicola, opportunistic fungi, Scolecobasidium.