Myxozoa + Polypodium : A Common Route to Endoparasitism

0000-0001-7279-715XCopyright © 2016 Elsevier B.V. or its licensors or contributors. The attached document is the authors' final accepted/submitted version of the journal article. You are advised to consult the publisher's version if you wish to cite from it

Redistributing ill-defined causes of death – a case study from the BURDEN 2020-project in Germany

Background The cause of death statistics in Germany include a relatively high share (26% in 2017) of ill-defined deaths (IDD). To make use of the cause of death statistics for Burden of Disease calculations we redistribute those IDD to valid causes of death. Methods The process of proportional redistribution is described in detail. It makes use of the distribution of the valid ICD-codes in the cause of death data. We use examples of stroke, diabetes, and heart failure to illustrate how IDD are reallocated. Results The largest increases in the number of deaths for both women and men were found for lower respiratory infections, diabetes mellitus, and stroke. The numbers of deaths for these causes more than doubled after redistribution. Conclusion This is the first comprehensive redistribution of IDD using the German cause of death statistics. Performing a redistribution is necessary for burden of disease analyses, otherwise there would be an underreporting of certain causes of death or large numbers of deaths coded to residual or unspecific codes.Peer Reviewe

Structural basis of mitochondrial membrane bending by the I-II-III2-IV2 supercomplex

Mitochondrial energy conversion requires an intricate architecture of the inner mitochondrial membrane1. Here we show that a supercomplex containing all four respiratory chain components contributes to membrane curvature induction in ciliates. We report cryo-electron microscopy and cryo-tomography structures of the supercomplex that comprises 150 different proteins and 311 bound lipids, forming a stable 5.8-MDa assembly. Owing to subunit acquisition and extension, complex I associates with a complex IV dimer, generating a wedge-shaped gap that serves as a binding site for complex II. Together with a tilted complex III dimer association, it results in a curved membrane region. Using molecular dynamics simulations, we demonstrate that the divergent supercomplex actively contributes to the membrane curvature induction and tubulation of cristae. Our findings highlight how the evolution of protein subunits of respiratory complexes has led to the I-II-III2-IV2 supercomplex that contributes to the shaping of the bioenergetic membrane, thereby enabling its functional specialization

A critical review of the Exit-Voice-Loyalty-Neglect literature: limitations, key challenges and directions for future research

The study of human behaviour holds a prominent role in organizational behavior literature. For almost 45 years, the exit, voice, loyalty and neglect typology has attracted scholars' interest and has been linked to employee responses towards dissatisfaction and problematic events in the workplace. This paper reviews the literature and identifies and addresses key theoretical and methodological deficiencies that the exit, voice, loyalty and neglect typology faces that have been either ignored or undeveloped. Moreover, by unpicking this typology as currently portrayed in the existing literature, it proposes key challenges that need to be addressed and provides directions for future research

Phylogenetische Bedeutung mesodermaler und neuronaler Strukturen bei Bryozoa

The position of the Bryozoa in the phylogenetic system is uncertain. While modern analyses of DNA sequence data place Bryozoa within Lophotrochozoa, most traditional morphological approaches argue for a common ancestry with deuterostomes. However, many characters used for this inference are only insufficiently investigated, causing problems in the assignment of character states. In the present study, aspects of bryozoan embryonic development as well as larval and adult morphology are investigated in order to enhance the morphological data set. The results are presented in five chapters which are based on two published and three submitted papers. In previous accounts, Phylactolaemata were found to show a considerable morphological distance to Stenolaemata and Gymnolaemata. Some of their characters were interpreted as being plesiomorphic, inherited from a common ancestor of Bryozoa, Phoronida, and Brachiopoda. In chapter 2 “Ganglion ultrastructure in phylactolaemate Bryozoa: Evidence for a neuroepithelium”, earlier speculations about a hollow cerebral ganglion, which arises by invagination can be confirmed. Chapter 3 “Body cavities in phylactolaemate Bryozoa” deals with the question of trimery of coelomic cavities, which had been hypothesized as a common character of tentaculates and deuterostomes. Recent studies, however, argue to refute this for Brachiopoda and Phoronida. In addition to this, it is shown by the present results that the epistome in phylactolaemates does contain a secondary body cavity, but this is confluent with the trunk coelom. Hence, there is no trimery in Phylactolaemata. Chapter 4 “Muscular systems of gymnolaemate bryozoan larvae” addresses the question, whether planktotrophic or lecithotrophic larvae can be regarded as ancestral for Bryozoa. Three- dimensional structure of musculature of larvae of five species, representing different types, has been investigated using fluorescence staining and confocal laser scanning microscopy. Musculature turns out to be of phylogenetic significance. In combination with existing data from the literature, the results support the idea of a multiple independent evolution of lecithotrophic from planktotrophic larvae. In Chapter 5 “Serotonergic and FMRFamidergic nervous systems in gymnolaemate bryozoan larvae” are examined in order to facilitate comparisons with equivalent data which have become available for many lophotrochozoan and deuterostome taxa during the last years. These data have successfully been applied in phylogenetic approaches, however, the currently available data in Bryozoa are inconsistent. Larval nervous systems of different species are examined using immunohistochemistry, confocal laser scanning microscopy and transmission electron microscopy. An ancestral pattern is proposed, which shows resemblance to larval nervous systems in annelids, molluscs and kamptozoans, but not to deuterstomes, phoronids and brachiopods. In chapter 6 “Origin of the Mesoderm in Membranipora membranacea”, embryonic stages of a planktotrophic cyphonautes larva are examined. Earlier studies on bryozoan embryology had assumed the mesoderm to originate from a quartet of cells at the vegetal pole of the embryo. Since these cells were also found to give rise to endoderm, this had been interpreted as a link to mesoderm formation in deuterostomes. However, these investigations were mostly done on lecithotrophic larvae, which are likely to be derived within Bryozoa. The present results show the mesoderm to originate by proliferation of an ectodermal cell into the blastocoel. In later stages, this cell gives rise to the larval musculature. This pattern is also present in spiralians. The results of the present study do not support a deuterostome affinity of Bryozoa, but argue for a position in the lophotrochozoa. No characters supporting sister-group relationships to brachiopods, phoronids or kamptozoans could be identified.Die Stellung der Bryozoa im phylogenetischen System der Metazoa ist nicht hinreichend geklärt. Während auf DNA-Sequenzdaten beruhende phylogenetische Analysen auf eine Zugehörigkeit zu den Lophotrochozoa hindeuten, hat die Mehrzahl der Analysen morphologischer Daten bisher für eine nähere Verwandtschaft zu den Deuterostomia gesprochen. Einige der für diese Analysen benutzten Merkmale sind allerdings unzureichend untersucht, was eine eindeutige Kodierung der Merkmalszustände erschwert. In der vorliegenden Arbeit werden Aspekte der Embryonalentwicklung, sowie der Larval- und Adultanatomie untersucht, um den vorhandenen Satz bekannter morphologischer Daten zu ergänzen. Die Ergebnisse werden in einzelnen Kapiteln präsentiert, die inhaltlich zwei bereits publizierten sowie drei eingereichten Artikeln entsprechen. In bisherigen phylogenetischen Betrachtungen wurden einige Merkmale der Phylactolaemata, welche eine gewisse morphologische Distanz zu den Gymnolaemata und Stenolaemata aufweisen, als Plesiomorphien interpretiert, die auf einen gemeinsamen Vorfahren von Bryozoa, Phoronida und Brachiopoda zurückzuführen sind. In Kapitel 2: „Ganglion ultrastructure in phylactolaemate Bryozoa: Evidence for a neuroepithelium“ können ältere Vermutungen erhärtet werden, wonach das Cerebralganglion bei den Phylactolaemata hohl ist und durch eine Invagination des Pharynxepithels entsteht. In Kapitel 3: „Body cavities in phylactolaemate Bryozoa“ wird der Frage nach einer Trimerie der Coelomräume nachgegangen, welche als gemeinsames Merkmal der Tentakulata und Deuterostomia hypothetisiert wurde. Nachdem neuere Studien diesen Zustand für die Phoronida und die Brachiopoda bereits widerlegt haben, kann hier gezeigt werden, dass im Epistom der Phylactolaemata zwar eine sekundäre Leibeshöhle auftritt, diese allerdings mit dem Körpercoelom konfluent ist. Eine Trimerie ist somit nicht vorhanden. Dem Kapitel 4 „Muscular systems of gymnolaemate bryozoan larvae“ liegt die bisher nicht eindeutig geklärte Frage zugrunde, ob lecithotrophe oder planktotrophe Larven für die Bryozoa als ursprünglich anzusehen sind. Die dreidimensionale Struktur der Muskulatur von Larven fünf verschiedener Arten, welche unterschiedliche Typen repräsentieren, wird mit Hilfe von Fluoreszenzfärbungen und konfokaler Laser-Scanning-Mikroskopie untersucht. Es zeigt sich, dass die Muskulatur als phylogenetisch informatives Merkmal verwendet werden kann. In Kombination mit bisher vorhandenen Daten unterstützen diese Ergebnisse die Theorie einer mehrfach unabhängigen Evolution lecithotropher aus planktotrophen Larven. Das Kapitel 5 „Serotonergic and FMRFamidergic nervous systems in gymnolaemate bryozoan larvae“ behandelt den Aufbau des larvalen Nervensystems. Während vergleichbare Merkmale in den letzten Jahren für eine Vielzahl von Teilgruppen der Lophotrochozoa und der Deuterostomia erhoben wurden und ein phylogenetisches Signal zu zeigen scheinen, sind die bisherigen Befunde für die Bryozoa inkonsistent. Die Nervensysteme von Larven verschiedener Bryozoenarten werden mit Hilfe von Immunhistochemie, konfokaler Laser Scanning-Mikroskopie und Transmissionselektronenmikroskopie untersucht. Es kann ein gemeinsames Muster erarbeitet werden, welches deutliche Übereinstimmungen zu den larvalen Nervensystemen der Annelida, Mollusca und Kamptozoa, nicht hingegen zu denen der Deuterostomia, Phoronida und Brachiopoda zeigt. Das Kapitel 6 „Origin of the Mesoderm in Membranipora membranacea“ wird an Entwicklungsstadien der planktotrophen Cyphonauteslarve von M. membranacea (Cheilostomata) die Herkunft des Mesoderms untersucht. In bisherigen, allerdings unzureichend dokumentierten, Befunden wurde das mesodermale Zellmaterial auf, am vegetativen Pol des Embryos gelegene, prospektive Endodermzellen zurückgeführt, was als Übereinstimmung zur Mesodermherkunft in den Deuterostomia interpretiert wurde. Diese Daten wurden jedoch durchweg an lecithotrophen Larven erhoben, welche mit einiger Sicherheit als abgeleitet innerhalb der Bryozoa angesehen werden können. In der untersuchten Art kann hingegen gezeigt werden, dass hier das Mesoderm aus einer ins Blastocoel proliferierenden Ektodermzelle entsteht, die durch Teilungen später die gesamte larvale Muskulatur bildet. Bei den Spiralia wird ein Teil des Mesoderms auf ähnliche Weise gebildet. Die in dieser Arbeit untersuchten Merkmale liefern keine neuen Argumente für eine Zuordnung der Bryozoa zu den Deuterostomia, sondern lassen sich im Gegenteil mit einer Einordnung in die Lophotrochozoa in Einklang bringen. Direkte Hinweise auf mögliche Schwestergruppenbeziehungen zu den Brachiopoda, Phoronida oder Kamptozoa sind indes nicht auffindbar

Diversification and repeated morphological transitions in endoparasitic cnidarians (Myxozoa: Malacosporea)

Malacosporeans are a poorly known myxozoan clade that uniquely demonstrates a tissue level of organisation. Thus, when exploiting their invertebrate hosts (freshwater bryozoans) they occur as non-motile sacs or vermiform stages capable of active swimming. We combine phylogenetic analyses of SSU and LSU rDNA with morphological observations to substantially enhance understanding of malacosporean diversification. The phylogenetic analyses incorporate the widest taxon sampling and geographic cover to date, reveal four novel malacosporean lineages and several putatively new species, one with a novel morphology of irregular, bulbous sacs and no musculature. This lineage currently forms the earliest branch of malacosporeans. Vermiform stages may have been lost or gained several times within the Malacosporea, even in cases where SSU sequence divergence is very low. Yet, sac and vermiform Buddenbrockia plumatellae appear to be separate species, an inference also supported by their utilisation of different bryozoan hosts. Cryptic speciation is also apparent with two novel, genetically divergent lineages (novel lineage 2 and Buddenbrockia sp. 4) being morphologically indistinguishable from known species. Finally, we provide evidence that fredericellid bryozoans are the main hosts for Tetracapsuloides bryosalmonae and are therefore most relevant for research on the ecology and management of Proliferative Kidney Disease of salmonid fish. © 2014 Elsevier Inc

Years of life lost to death

Die Kenntnis darüber, welche Erkrankungen und Todesursachen er-heblich zu den durch Sterblichkeit verlorenen Lebensjahren („years of life lost“, YLL) beitragen, kann zur besseren Fokussierung entsprechender Präventions- und Versorgungsprogramme beitragen. Im Rahmen des Projekts BURDEN 2020 am Robert Koch-Institut wurden die YLL deutschlandweit für spezifische Todesursachen ermittelt.Peer Reviewe