Reconsidering endemism in the Northeastern Limestone Alps

The restricted distribution of endemic plant species in the Northern Limestone Alps is commonly explained by a severe loss of biotypes and genetic plasticity during Pleistocene glaciation. In the present paper we examine the ecological features of the regional endemic species and plant communities to see if they actually support this interpretation. In particular, we focus on (1) species composition and habitat characteristics of endemic plant communities, (2) the frequency of endemic species in different plant communities and habitat types, (3) the correlation between the frequency of endemic species and the density of the vegetation cover and (4) the altitudinal distribution of endemic species. Concerning endemic plant communities, there is considerable variation in species composition as well as in habitat requirements. Communities of rock, scree and snowbed habitats are characterised by the predominance of endemic or subendemic species, whereas endemic alpine grassland types contain mainly non-endemic plants. Regarding the distribution of endemic plants, no uniform trend could be detected. The endemic species pool contains plants restricted to azonal stands as well as typical species of climax grasslands and widespread generalists. Some endemics distinctly prefer open vegetation types, others predominantly occur in dense grasslands. The bulk of the species considered performs best in the lower alpine zone, some others are especially common in the subalpine zone, whereas only one species showed an occurrence peak in the upper alpine belt. In summary, it may be said that the habitat requirements of endemic plants are rather species-specific and that there are only a few general trends. This fact seems to indicate the complex nature of the phenomenon of regional endemism, which is influenced by a range of factors. The prevailing historical explanation may not be appropriate for every species. Hence, the consideration of current ecological conditions in addition to historical factors may provide a more comprehensive explanation of regional endemism

Molecular differentiation of commercial varieties and feral populations of oilseed rape (Brassica napus L.)

Background For assessing the risk of escape of transgenes from cultivation, the persistence of feral populations of crop plants is an important aspect. Feral populations of oilseed rape, Brassica napus, are well known, but only scarce information is available on their population dynamics, particularly in Central Europe. To investigate genetic diversity, origin and persistence of feral oilseed rape in Austria, we compared variation at nine polymorphic microsatellite loci in eight feral populations with 19 commercial varieties. Results Overall, commercial varieties and feral populations showed a similar pattern of genetic variation and a similar level of observed heterozygosity. The two groups, however, shared less than 50% of the alleles and no multilocus genotype. A significant among-group (commercial varieties versus feral populations) component of genetic variation was observed (AMOVA: FCT = 0.132). Pairwise comparisons between varieties and feral populations showed moderate to very high genetic differentiation (FST = 0.209 - 0.900). The software STRUCTURE also demonstrated a clear separation between commercial varieties and feral samples: out of 17 identified genetic clusters, only one comprised plants from both a commercial variety and feral sites. Conclusions The results suggest that feral oilseed rape is able to maintain persistent populations. The feral populations may have derived from older cultivars that were not included in our analyses or perhaps have already hybridised with related crops or wild relatives. Feral populations therefore have to be considered in ecological risk assessment and future coexistence measures as a potential hybridisation partner of transgenic oilseed rape

A gut bacterial signature in blood and liver tissue characterizes cirrhosis and hepatocellular carcinoma

BackgroundHCC is the leading cause of cancer in chronic liver disease. A growing body of experimental mouse models supports the notion that gut-resident and liver-resident microbes control hepatic immune responses and, thereby, crucially contribute to liver tumorigenesis. However, a comprehensive characterization of the intestinal microbiome in fueling the transition from chronic liver disease to HCC in humans is currently missing.MethodsHere, we profiled the fecal, blood, and liver tissue microbiome of patients with HCC by 16S rRNA sequencing and compared profiles to nonmalignant cirrhotic and noncirrhotic NAFLD patients.ResultsWe report a distinct bacterial profile, defined from 16S rRNA gene sequences, with reduced α-and β-diversity in the feces of patients with HCC and cirrhosis compared to NAFLD. Patients with HCC and cirrhosis exhibited an increased proportion of fecal bacterial gene signatures in the blood and liver compared to NAFLD. Differential analysis of the relative abundance of bacterial genera identified an increased abundance of Ruminococcaceae and Bacteroidaceae in blood and liver tissue from both HCC and cirrhosis patients compared to NAFLD. Fecal samples from cirrhosis and HCC patients both showed a reduced abundance for several taxa, including short-chain fatty acid-producing genera, such as Blautia and Agathobacter. Using paired 16S rRNA and transcriptome sequencing, we identified a direct association between gut bacterial genus abundance and host transcriptome response within the liver tissue.ConclusionsOur study indicates perturbations of the intestinal and liver-resident microbiome as a critical determinant of patients with cirrhosis and HCC

Dietary lipids fuel GPX4-restricted enteritis resembling Crohn’s disease

Abstract: The increased incidence of inflammatory bowel disease (IBD) has become a global phenomenon that could be related to adoption of a Western life-style. Westernization of dietary habits is partly characterized by enrichment with the ω-6 polyunsaturated fatty acid (PUFA) arachidonic acid (AA), which entails risk for developing IBD. Glutathione peroxidase 4 (GPX4) protects against lipid peroxidation (LPO) and cell death termed ferroptosis. We report that small intestinal epithelial cells (IECs) in Crohn’s disease (CD) exhibit impaired GPX4 activity and signs of LPO. PUFAs and specifically AA trigger a cytokine response of IECs which is restricted by GPX4. While GPX4 does not control AA metabolism, cytokine production is governed by similar mechanisms as ferroptosis. A PUFA-enriched Western diet triggers focal granuloma-like neutrophilic enteritis in mice that lack one allele of Gpx4 in IECs. Our study identifies dietary PUFAs as a trigger of GPX4-restricted mucosal inflammation phenocopying aspects of human CD

Numerische Klassifikation und Ordination in der alpinen Vegetationsökologie als Beitrag zur Verknüpfung moderner "Computermethoden" mit der pflanzensoziologischen Tradition

Als Beitrag zur Verknüpfung numerischer Klassifikationsmethoden sowie der objektiven Auswahl der Aufnahmeflächen mit der pflanzensoziologischen Tradition in Mitteleuropa wird eine Studie zur Klassifikation und Identifizierbarkeit hochalpiner Rasengesellschaften (Caricetea curvulae- und Elyno-Seslerietea-Gesellschaften) vorgestellt. Die zentrale Frage ist, ob eine Gruppe konkreter Phytozönosen, die bei der Aufnahme im Gelände mit einem "BRAUN-BLANQUET'schen" Syntaxon identifiziert wurde, auch als homogene Gruppe in einer numerischen Klassifikation erscheint. Zur numerischen Gruppierung wurde das Computerprogramm TWINSPAN verwendet. Das TWINSPAN-Ergebnis wurde mit dem Ergebnis einer numerischen Ordination (mittels Programm DECORANA) kombiniert, um das Resultat der Identifikation mit jenem der numerischen Klassifikation vergleichen zu können. Die Gruppen der numerischen Analyse stimmen in weiten Grenzen mit den Syntaxa des BRAUN-BLANQUET'schen Systems überein. Es kommt also offenbar bei der Anwendung der numerischen Verfahren "nichts Neues" heraus, zumindest nichts grundsätzlich Neues. Diese Tatsache wird erklärt durch die Natur phytosoziologischer Daten als redundantes Informationssystem. Das heißt, eine gegebene Artenkombination impliziert bereits die Mengenverhältnisse, in denen die Arten in einer Gesellschaft miteinander vorkommen. Dadurch wurde bei der traditionellen Klassifikation relativ wenig Information verloren, da durch die Beachtung der Deckungsgrade zumindest der dominanten Arten der Rest an Arten automatisch miteinbezogen war. Das heißt, daß der Hauptvorteil der numerischen Methoden, nämlich die gesamte Artengarnitur für die Klassifikation zu berücksichtigen, eigentlich gar keinen essentiellen Informationsgewinn darstellt. Insgesamt sollte man die numerischen Methoden als eine Art "sauberere" Lösung eines multivariaten Problems betrachten, abgesehen von Vorteilen, die in einer leichteren und schnelleren Bearbeitung der Daten liegen, ebenso wie sie eine objektivere Basis zur Formulierung und Bewertung von Hypothesen liefern.As part of an attempt to combine numerical classification methods as well as objective sampling procedures with the phytosociological tradition of Central Europe, a comparative study was carried out on identification and classification of high-altitude grassland communities in the Alps. The central question was whether a group of concrete phytocoenoses, which had been identified with a particular BRAUN-BLANQUET syntaxon in the field, would appear as a homogeneous group in a numerical classification. For numerical classification the computer program TWINSPAN was used, and for evaluating the identification and classification results, the TWINSPAN output was also displayed in ordination diagrams. The ordination was carried out by the computer program DECORANA. Within broad limits the groups of the numerical analysis coincide with the syntaxa of the BRAUN-BLANQUET-system, identified in the field. This can be explained by the character of phytosociological data as being a redundant information system. By a given species composition in a plant community, the cover values of the species are predetermined. Emphazising mainly character species or dominant species with their cover values, as was done in traditional classification, means nothing more than that little information was lost when ignoring the whole species list. Thus the main feature of the numerical methods, namely to treat the whole species composition, is in fact no essential improvement for classification. The numerical methods should be considered as more sophisticated, and their main advantage will be the easier and accelerated data handling as well as a more objective basis for hypothesis generation

Report on the Committee for Nomina Conservanda, Ambigua, Inversa and Mutata 1

Mit der dritten Auflage des Internationalen Code der Pflanzensoziologischen Nomenklatur wurde ein spezielles Komitee etabliert, um eine Entscheidung der Nomenklaturkommission über eingereichte Vorschläge für nomina ambigua, nomina inversa, nomina mutata und nomina conservanda zu erleichtern und zu beschleunigen. Wir legen hier den ersten Report dieses Komitees vor. Im ersten Teil der Arbeit wird ein kurzer Überblick über die Hauptprobleme mit jeder einzelnen dieser vier Kategorien gegeben. Im zweiten Teil werden 19 Vorschläge diskutiert und eine Empfehlung gegeben, ob der Vorschlag akzeptiert oder abgelehnt werden sollte. Autoren, die einen Vorschlag an die Nomenklaturkommission senden möchten, werden gebeten, diesen Report als Richtlinie zu nutzen.With the 3rd edition of the International Code of Phytosociological Nomenclature, a special Committee was established to faciliate and accelerate the decision of the Nomenclature Commission on submitted proposals for nomina ambigua, nomina inversa, nomina mutata, and nomina conservanda. Here we present the first report of this Committee. In the first part of the paper, a short overview of the major problems related with each of the four categories is given. In the second part, 19 proposals are discussed together with a recommendation whether the proposal should be accepted or rejected. Authors who wish to submit a proposal to the Nomenclature Commission are asked to use this report as a guideline