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Burkhardt P, Colgren J, Medhus A, Digel L, Naumann B, Soto-Angel JJ, Nordmann EL, Sachkova MY, Kittelmann M. Syncytial nerve net in a ctenophore adds insights on the evolution of nervous systems. Science 2023; 380:293-297. [PMID: 37079688 DOI: 10.1126/science.ade5645] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
A fundamental breakthrough in neurobiology has been the formulation of the neuron doctrine by Santiago Ramón y Cajal, which stated that the nervous system is composed of discrete cells. Electron microscopy later confirmed the doctrine and allowed the identification of synaptic connections. In this work, we used volume electron microscopy and three-dimensional reconstructions to characterize the nerve net of a ctenophore, a marine invertebrate that belongs to one of the earliest-branching animal lineages. We found that neurons in the subepithelial nerve net have a continuous plasma membrane that forms a syncytium. Our findings suggest fundamental differences of nerve net architectures between ctenophores and cnidarians or bilaterians and offer an alternative perspective on neural network organization and neurotransmission.
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Affiliation(s)
- Pawel Burkhardt
- Michael Sars Centre, University of Bergen, 5008 Bergen, Norway
| | - Jeffrey Colgren
- Michael Sars Centre, University of Bergen, 5008 Bergen, Norway
| | - Astrid Medhus
- Michael Sars Centre, University of Bergen, 5008 Bergen, Norway
| | - Leonid Digel
- Michael Sars Centre, University of Bergen, 5008 Bergen, Norway
| | - Benjamin Naumann
- Institut für Biowissenschaften, Allgemeine und Spezielle Zoologie, Universität Rostock, 18055 Rostock, Germany
| | | | | | | | - Maike Kittelmann
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, UK
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2
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Göhde R, Naumann B, Laundon D, Imig C, McDonald K, Cooper BH, Varoqueaux F, Fasshauer D, Burkhardt P. Choanoflagellates and the ancestry of neurosecretory vesicles. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190759. [PMID: 33550951 PMCID: PMC7934909 DOI: 10.1098/rstb.2019.0759] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/26/2020] [Indexed: 01/08/2023] Open
Abstract
Neurosecretory vesicles are highly specialized trafficking organelles that store neurotransmitters that are released at presynaptic nerve endings and are, therefore, important for animal cell-cell signalling. Despite considerable anatomical and functional diversity of neurons in animals, the protein composition of neurosecretory vesicles in bilaterians appears to be similar. This similarity points towards a common evolutionary origin. Moreover, many putative homologues of key neurosecretory vesicle proteins predate the origin of the first neurons, and some even the origin of the first animals. However, little is known about the molecular toolkit of these vesicles in non-bilaterian animals and their closest unicellular relatives, making inferences about the evolutionary origin of neurosecretory vesicles extremely difficult. By comparing 28 proteins of the core neurosecretory vesicle proteome in 13 different species, we demonstrate that most of the proteins are present in unicellular organisms. Surprisingly, we find that the vesicular membrane-associated soluble N-ethylmaleimide-sensitive factor attachment protein receptor protein synaptobrevin is localized to the vesicle-rich apical and basal pole in the choanoflagellate Salpingoeca rosetta. Our 3D vesicle reconstructions reveal that the choanoflagellates S. rosetta and Monosiga brevicollis exhibit a polarized and diverse vesicular landscape reminiscent of the polarized organization of chemical synapses that secrete the content of neurosecretory vesicles into the synaptic cleft. This study sheds light on the ancestral molecular machinery of neurosecretory vesicles and provides a framework to understand the origin and evolution of secretory cells, synapses and neurons. This article is part of the theme issue 'Basal cognition: multicellularity, neurons and the cognitive lens'.
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Affiliation(s)
- Ronja Göhde
- Sars International Centre for Molecular Marine Biology, University of Bergen, 5006 Bergen, Norway
| | - Benjamin Naumann
- Institute of Zoology and Evolutionary Research, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Davis Laundon
- Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Cordelia Imig
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, 37075 Gottingen, Germany
| | - Kent McDonald
- Electron Microscope Laboratory, University of California, Berkeley, CA 94720, USA
| | - Benjamin H. Cooper
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, 37075 Gottingen, Germany
| | - Frédérique Varoqueaux
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Dirk Fasshauer
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Pawel Burkhardt
- Sars International Centre for Molecular Marine Biology, University of Bergen, 5006 Bergen, Norway
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Levit GS, Hoßfeld U, Naumann B, Lukas P, Olsson L. The biogenetic law and the Gastraea theory: From Ernst Haeckel's discoveries to contemporary views. J Exp Zool B Mol Dev Evol 2021; 338:13-27. [PMID: 33724681 DOI: 10.1002/jez.b.23039] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 02/08/2021] [Accepted: 02/18/2021] [Indexed: 12/28/2022]
Abstract
More than 150 years ago, in 1866, Ernst Haeckel published a book in two volumes called Generelle Morphologie der Organismen (General Morphology of Organisms) in the first volume of which he formulated his biogenetic law, famously stating that ontogeny recapitulates phylogeny. Here, we describe Haeckel's original idea as first formulated in the Generelle Morphologie der Organismen and later further developed in other publications until the present situation in which molecular data are used to test the "hourglass model," which can be seen as a modern version of the biogenetic law. We also tell the story about his discovery, while traveling in Norway, of an unknown organism, Magosphaera planula, that was important in that it helped to precipitate his ideas into what was to become the Gastraea theory. We also follow further development and reformulations of the Gastraea theory by other scientists, notably the Russian school. Elias Metchnikoff developed the Phagocytella hypothesis for the origin of metazoans based on studies of a colonial flagellate. Alexey Zakhvatin focused on deducing the ancestral life cycle and the cell types of the last common ancestor of all metazoans, and Kirill V. Mikhailov recently pursued this line of research further.
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Affiliation(s)
- Georgy S Levit
- AG Biologiedidaktik, Friedrich-Schiller-Universität Bienenhaus, Jena, Germany
| | - Uwe Hoßfeld
- AG Biologiedidaktik, Friedrich-Schiller-Universität Bienenhaus, Jena, Germany
| | - Benjamin Naumann
- Institut für Zoologie und Evolutionsforschung, Friedrich-Schiller-Universität, Jena, Germany
| | - Paul Lukas
- Institut für Zoologie und Evolutionsforschung, Friedrich-Schiller-Universität, Jena, Germany
| | - Lennart Olsson
- Institut für Zoologie und Evolutionsforschung, Friedrich-Schiller-Universität, Jena, Germany
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Naumann B, Schweiger S, Hammel JU, Müller H. Parallel evolution of direct development in frogs - Skin and thyroid gland development in African Squeaker Frogs (Anura: Arthroleptidae: Arthroleptis). Dev Dyn 2021; 250:584-600. [PMID: 33354814 DOI: 10.1002/dvdy.275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Cases of parallel evolution offer the possibility to identify adaptive traits and to uncover developmental constraints on the evolutionary trajectories of these traits. The independent evolution of direct development from the ancestral biphasic life history in frogs is such a case of parallel evolution. In frogs, aquatic larvae (tadpoles) differ profoundly from their adult forms and exhibit a stunning diversity regarding their habitats, morphology and feeding behaviors. The transition from the tadpole to the adult is a climactic, thyroid hormone (TH)-dependent process of profound and fast morphological rearrangement called metamorphosis. One of the organ systems that experiences the most comprehensive metamorphic rearrangements is the skin. Direct-developing frogs lack a free-swimming tadpole and hatch from terrestrial eggs as fully formed froglets. In the few species examined, development is characterized by the condensed and transient formation of some tadpole-specific features and the early formation of adult-specific features during a "cryptic" metamorphosis. RESULTS We show that skin in direct-developing African squeaker frogs (Arthroleptis) is also repatterned from a tadpole-like to an adult-like histology during a cryptic metamorphosis. This repatterning correlates with histological thyroid gland maturation. A comparison with data from the Puerto Rican coqui (Eleutherodactylus coqui) reveals that the evolution of direct development in these frogs is associated with a comparable heterochronic shift of thyroid gland maturation. CONCLUSION This suggests that the development of many adult features is still dependent on, and possibly constrained by, the ancestral dependency on thyroid hormone signaling.
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Affiliation(s)
| | - Susan Schweiger
- Institut für Zoologie und Evolutionsforschung, Jena, Germany
| | - Jörg U Hammel
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung, Außenstelle am DESY, Hamburg, Germany
| | - Hendrik Müller
- Institut für Zoologie und Evolutionsforschung, Jena, Germany.,Zentralmagazin Naturwissenschaftlicher Sammlungen, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany.,Department of Life Sciences, The Natural History Museum, London, UK
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Naumann B, Reip HS, Akkari N, Neubert D, Hammel JU. Inside the head of a cybertype – three-dimensional reconstruction of the head muscles of Ommatoiulus avatar (Diplopoda: Juliformia: Julidae) reveals insights into the feeding movements of Juliformia. Zool J Linn Soc 2019. [DOI: 10.1093/zoolinnean/zlz109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractThe origin and diversification of the arthropod head is one of the major topics in the field of evolutionary morphology of Arthropoda. Among the major arthropod groups, Myriapoda and, more precisely Diplopoda, are generally poorly studied regarding their head anatomy. However, this group is of pivotal importance to understand the evolutionary functional morphology of the arthropod head. In this study, we investigate the complete musculoskeletal system of the diplopod head with a detailed description of the cephalic anatomy of the recently described species Ommatoiulus avatar. The comparison of our data with the literature on the few other species available show that the morphology of the musculoskeletal system within Juliformia, a subgroup of the Diplopoda, is relatively conservative. Using video recordings of the feeding movements in addition to the anatomical data, we revise the mechanism of the mandibular movements in Juliformia. There was a controversy whether mandibular abduction is an active process, facilitated by contraction of an abductor muscle, or if it is a passive process, mediated by tentorial and gnathochilarial movements not involving a direct abduction by muscular contraction. We show that mandibular abduction in Ommatoiulus is an active movement involving the contraction of an abductor muscle. This is similar to the mandibular abduction in other arthropod groups.
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Affiliation(s)
- Benjamin Naumann
- Institute of Zoology and Evolutionary Research, Friedrich-Schiller-University, Jena, Germany
- Leibniz Institute on Aging – Fritz Lipmann Institute, Jena, Germany
| | - Hans S Reip
- Department of Soil Zoology, Senckenberg Museum of Natural History, Görlitz, Germany
| | - Nesrine Akkari
- 3rd Zoological Department, Natural History Museum Vienna, Vienna, Austria
| | - David Neubert
- Institute of Zoology and Evolutionary Research, Friedrich-Schiller-University, Jena, Germany
| | - Jörg U Hammel
- Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany
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Abstract
Choanoflagellates are the closest unicellular relatives of animals (Metazoa). These tiny protists display complex life histories that include sessile as well as different pelagic stages. Some choanoflagellates have the ability to form colonies as well. Up until recently, these colonies have been described to consist of mostly identical cells showing no spatial cell differentiation, which supported the traditional view that spatial cell differentiation, leading to the co-existence of specific cell types in animals, evolved after the split of the last common ancestor of the Choanoflagellata and Metazoa. The recent discovery of single cells in colonies of the choanoflagellate Salpingoeca rosetta that exhibit unique cell morphologies challenges this traditional view. We have now reanalyzed TEM serial sections, aiming to determine the degree of similarity of S. rosetta cells within a rosette colony. We investigated cell morphologies and nuclear, mitochondrial, and food vacuole volumes of 40 individual cells from four different S. rosetta rosette colonies and compared our findings to sponge choanocytes. Our analysis shows that cells in a choanoflagellate colony differ from each other in respect to cell morphology and content ratios of nuclei, mitochondria, and food vacuoles. Furthermore, cell disparity within S. rosetta colonies is slightly higher compared to cell disparity within sponge choanocytes. Moreover, we discovered the presence of plasma membrane contacts between colonial cells in addition to already described intercellular bridges and filo-/pseudopodial contacts. Our findings indicate that the last common ancestor of Choanoflagellata and Metazoa might have possessed plasma membrane contacts and spatial cell disparity during colonial life history stages.
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Affiliation(s)
- Benjamin Naumann
- Institute of Zoology and Evolutionary Research, Friedrich Schiller University Jena, Jena, Germany
| | - Pawel Burkhardt
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
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Konheiser J, Müller SE, Magin A, Naumann B, Ferrari A. Source term calculation and validation for 18F-production with a cyclotron for medical applications at HZDR. J Radiol Prot 2019; 39:906-919. [PMID: 31216517 DOI: 10.1088/1361-6498/ab2ae8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this document we present the calculation and experimental validation of a source term for 18F-production with a cyclotron for medical applications operating at 18 MeV proton energy and 30 μA proton current. The Monte Carlo codes MCNP6 and FLUKA were used for the calculation of the source term. In addition, the radiation field around the 18O-enriched water target was simulated with the two codes. To validate the radiation field obtained in the simulation, an experimental program has been started using activation samples which are placed close to the water target during an 18F-production run of the cyclotron. After the irradiation, the samples are analysed and the resulting activation is compared to Monte Carlo calculations of the expected sample activation. We find good agreement between simulations and experimental results, with most calculation to experiment (C/E) ratios well between 0.6 and 1.4.
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Affiliation(s)
- J Konheiser
- Helmholtz-Zentrum Dresden-Rossendorf, D-01328 Dresden, Germany
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Naumann B, Schmidt J, Olsson L. FoxN3
is necessary for the development of the interatrial septum, the ventricular trabeculae and the muscles at the head/trunk interface in the African clawed frog,
Xenopus laevis
(Lissamphibia: Anura: Pipidae). Dev Dyn 2019; 248:323-336. [DOI: 10.1002/dvdy.25] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 02/18/2019] [Accepted: 02/22/2019] [Indexed: 12/22/2022] Open
Affiliation(s)
- Benjamin Naumann
- Institut für Zoologie und EvolutionsforschungFriedrich‐Schiller‐Universität Jena Germany
| | - Jennifer Schmidt
- Institut für Zoologie und EvolutionsforschungFriedrich‐Schiller‐Universität Jena Germany
| | - Lennart Olsson
- Institut für Zoologie und EvolutionsforschungFriedrich‐Schiller‐Universität Jena Germany
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9
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Naumann B, Englert C. Dispersion/reaggregation in early development of annual killifishes: Phylogenetic distribution and evolutionary significance of a unique feature. Dev Biol 2018; 442:69-79. [PMID: 30040922 DOI: 10.1016/j.ydbio.2018.07.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/17/2018] [Accepted: 07/17/2018] [Indexed: 01/08/2023]
Abstract
Annual killifishes are members of the Aplocheiloidea and live in ephemeral habitats that desiccate regularly during the dry season and refill during the rainy season. Populations of these fishes survive the dry season by producing drought-resistant diapausing eggs that are buried in the substrate. When the pool refills during the rainy season the juveniles hatch, grow rapidly and reproduce until the pool desiccates again during the next dry season. The association with such unpredictable habitats has led to the evolution to a variety of developmental adaptations such as a dispersed/reaggregation phase of the deep blastomeres, three possible diapause stages, extreme tolerance to high salinity and anoxia, an efficient DNA repair system and an extremely short life span. Here, we review the course of the dispersed/reaggregation phase, its evolution and phylogenetic distribution and diversity within the Aplocheiloidea. The phenomenon of blastomere dispersion/reaggregation in these fishes was first described in the 1960s and 70s. Blastomeres of most teleost fishes segregate into three groups that give rise to the enveloping cell layer, the yolk syncytial layer and the deep blastomeres that will form the embryo itself. When epiboly commences, the deep blastomeres form a more or less coherent cell sheet with a so called embryonic shield at it marginal zone marking the area where gastrulation takes place. In annual killifishes, the deep blastomeres segregate when epiboly starts and disperse when epiboly commences. After epiboly has been completed, the deep blastomeres are randomly distributed and migrate all over the enveloping cell layer. After several days they start to reaggregate and form the actual embryo that starts gastrulation. The evolutionary origin and mechanism behind this peculiar developmental pathway have puzzled developmental biologists for almost 50 years. However, several of these annual killifishes (Nothobranchius furzeri, Austrofundulus limnaeus, Austrolebias charrua and Austrolebias bellottii) have become model organisms in studies on developmental physiology, aging and stress tolerance. This has led to the establishment of modern genetic techniques such as transgenesis and cell fate mapping that are now used to tackle questions about the origin and mechanisms behind the dispersal/reaggregation phase.
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Affiliation(s)
- Benjamin Naumann
- Institute of Zoology and Evolutionary Research, Jena, Germany; Leibniz Institute on Aging - Fritz Lipmann Institute, Jena, Germany.
| | - Christoph Englert
- Leibniz Institute on Aging - Fritz Lipmann Institute, Jena, Germany; Institute of Biochemistry and Biophysics, Jena, Germany
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10
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Naumann B, Olsson L. Three-dimensional reconstruction of the cranial and anterior spinal nerves in early tadpoles of Xenopus laevis (Pipidae, Anura). J Comp Neurol 2018; 526:836-857. [PMID: 29218708 DOI: 10.1002/cne.24370] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 11/22/2017] [Accepted: 11/26/2017] [Indexed: 01/29/2023]
Abstract
Xenopus laevis is one of the most widely used model organism in neurobiology. It is therefore surprising, that no detailed and complete description of the cranial nerves exists for this species. Using classical histological sectioning in combination with fluorescent whole mount antibody staining and micro-computed tomography we prepared a detailed innervation map and a freely-rotatable three-dimensional (3D) model of the cranial nerves and anterior-most spinal nerves of early X. laevis tadpoles. Our results confirm earlier descriptions of the pre-otic cranial nerves and present the first detailed description of the post-otic cranial nerves. Tracing the innervation, we found two previously undescribed head muscles (the processo-articularis and diaphragmatico-branchialis muscles) in X. laevis. Data on the cranial nerve morphology of tadpoles are scarce, and only one other species (Discoglossus pictus) has been described in great detail. A comparison of Xenopus and Discoglossus reveals a relatively conserved pattern of the post-otic and a more variable morphology of the pre-otic cranial nerves. Furthermore, the innervation map and the 3D models presented here can serve as an easily accessible basis to identify alterations of the innervation produced by experimental studies such as genetic gain- and loss of function experiments.
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Affiliation(s)
- Benjamin Naumann
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität, Jena, Germany
| | - Lennart Olsson
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität, Jena, Germany
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11
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Warth P, Hilton EJ, Naumann B, Olsson L, Konstantinidis P. Development of the muscles associated with the mandibular and hyoid arches in the Siberian sturgeon, Acipenser baerii (Acipenseriformes: Acipenseridae). J Morphol 2017; 279:163-175. [PMID: 29068071 DOI: 10.1002/jmor.20761] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 09/24/2017] [Accepted: 09/29/2017] [Indexed: 01/10/2023]
Abstract
The skeleton of the jaws and neurocranium of sturgeons (Acipenseridae) are connected only through the hyoid arch. This arrangement allows considerable protrusion and retraction of the jaws and is highly specialized among ray-finned fishes (Actinopterygii). To better understand the unique morphology and the evolution of the jaw apparatus in Acipenseridae, we investigated the development of the muscles of the mandibular and hyoid arches of the Siberian sturgeon, Acipenser baerii. We used a combination of antibody staining and formalin-induced fluorescence of tissues imaged with confocal microscopy and subsequent three-dimensional reconstruction. These data were analyzed to address the identity of previously controversial and newly discovered muscle portions. Our results indicate that the anlagen of the muscles in A. baerii develop similarly to those of other actinopterygians, although they differ by not differentiating into distinct muscles. This is exemplified by the subpartitioning of the m. adductor mandibulae as well as the massive m. protractor hyomandibulae, for which we found a previously undescribed portion in each. The importance of paedomorphosis for the evolution of Acipenseriformes has been discussed before and our results indicate that the muscles of the mandibular and the hyoid may be another example for heterochronic evolution.
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Affiliation(s)
- Peter Warth
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität Jena, Germany
| | - Eric J Hilton
- Department of Fisheries Science, Virginia Institute of Marine Science, College of William & Mary, Gloucester Point, Virginia
| | - Benjamin Naumann
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität Jena, Germany
| | - Lennart Olsson
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität Jena, Germany
| | - Peter Konstantinidis
- Department of Fisheries and Wildlife, Oregon State University, Corvallis, Oregon
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12
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Naumann B, Warth P, Olsson L, Konstantinidis P. The development of the cucullaris muscle and the branchial musculature in the Longnose Gar, (Lepisosteus osseus, Lepisosteiformes, Actinopterygii) and its implications for the evolution and development of the head/trunk interface in vertebrates. Evol Dev 2017; 19:263-276. [PMID: 29027738 DOI: 10.1111/ede.12239] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The vertebrate head/trunk interface is the region of the body where the different developmental programs of the head and trunk come in contact. Many anatomical structures that develop in this transition zone differ from similar structures in the head or the trunk. This is best exemplified by the cucullaris/trapezius muscle, spanning the head/trunk interface by connecting the head to the pectoral girdle. The source of this muscle has been claimed to be either the unsegmented head mesoderm or the somites of the trunk. However most recent data on the development of the cucullaris muscle are derived from tetrapods and information from actinopterygian taxa is scarce. We used classical histology in combination with fluorescent whole-mount antibody staining and micro-computed tomography to investigate the developmental pattern of the cucullaris and the branchial muscles in a basal actinopterygian, the Longnose gar (Lepisosteus osseus). Our results show (1) that the cucullaris has been misidentified in earlier studies on its development in Lepisosteus. (2) Cucullaris development is delayed compared to other head and trunk muscles. (3) This developmental pattern of the cucullaris is similar to that reported from some tetrapod taxa. (4) That the retractor dorsalis muscle of L. osseus shows a delayed developmental pattern similar to the cucullaris. Our data are in agreement with an explanatory scenario for the cucullaris development in tetrapods, suggesting that these mechanisms are conserved throughout the Osteichthyes. Furthermore the developmental pattern of the retractor dorsalis, also spanning the head/trunk interface, seems to be controlled by similar mechanisms.
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Affiliation(s)
- Benjamin Naumann
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität, Jena, Germany
| | - Peter Warth
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität, Jena, Germany
| | - Lennart Olsson
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität, Jena, Germany
| | - Peter Konstantinidis
- Department of Fisheries and Wildlife, Oregon State University, Corvallis, Oregon
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13
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Warth P, Hilton EJ, Naumann B, Olsson L, Konstantinidis P. Development of the skull and pectoral girdle in Siberian sturgeon,Acipenser baerii, and Russian sturgeon,Acipenser gueldenstaedtii(Acipenseriformes: Acipenseridae). J Morphol 2017; 278:418-442. [DOI: 10.1002/jmor.20653] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 12/23/2016] [Accepted: 12/30/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Peter Warth
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität Jena; Germany
| | - Eric J. Hilton
- Department of Fisheries Science; Virginia Institute of Marine Science, College of William & Mary; Gloucester Point Virginia
| | - Benjamin Naumann
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität Jena; Germany
| | - Lennart Olsson
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität Jena; Germany
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14
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Konheiser J, Naumann B, Ferrari A, Brachem C, Müller SE. Source terms, shielding calculations and soil activation for a medical cyclotron. J Radiol Prot 2016; 36:819-831. [PMID: 27725341 DOI: 10.1088/0952-4746/36/4/819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Calculations of the shielding and estimates of soil activation for a medical cyclotron are presented in this work. Based on the neutron source term from the 18O(p,n)18F reaction produced by a 28 MeV proton beam, neutron and gamma dose rates outside the building were estimated with the Monte Carlo code MCNP6 (Goorley et al 2012 Nucl. Technol. 180 298-315). The neutron source term was calculated with the MCNP6 code and FLUKA (Ferrari et al 2005 INFN/TC_05/11, SLAC-R-773) code as well as with supplied data by the manufacturer. MCNP and FLUKA calculations yielded comparable results, while the neutron yield obtained using the manufacturer-supplied information is about a factor of 5 smaller. The difference is attributed to the missing channels in the manufacturer-supplied neutron source terms which considers only the 18O(p,n)18F reaction, whereas the MCNP and FLUKA calculations include additional neutron reaction channels. Soil activation was performed using the FLUKA code. The estimated dose rate based on MCNP6 calculations in the public area is about 0.035 µSv h-1 and thus significantly below the reference value of 0.5 µSv h-1 (2011 Strahlenschutzverordnung, 9 Auflage vom 01.11.2011, Bundesanzeiger Verlag). After 5 years of continuous beam operation and a subsequent decay time of 30 d, the activity concentration of the soil is about 0.34 Bq g-1.
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Affiliation(s)
- J Konheiser
- Helmholtz-Zentrum Dresden-Rossendorf, Postfach 510119, 01314 Dresden, Germany
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Konstantinidis P, Warth P, Naumann B, Metscher B, Hilton EJ, Olsson L. The Developmental Pattern of the Musculature Associated with the Mandibular and Hyoid Arches in the Longnose Gar,Lepisosteus osseus(Actinopterygii, Ginglymodi, Lepisosteiformes). COPEIA 2015. [DOI: 10.1643/ot-14-195] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Sahre P, Kaden M, Schönmuth T, Pawelke J, Naumann B, Reichelt U. Dose contributions due to radiation scattered by air (skyshine) in the case of x-ray machines. KERNTECHNIK 2013. [DOI: 10.3139/124.110267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Radiation transport simulations had to be done in preparation of operation of the X-ray tube ISOVOLT 320 kV/13mA in a special laboratory. At first simulation was done without shielding the roof of the laboratory, showing a dose rate maximum of more than 100 mSv/h. This dose rate results in a skyshine dose rate of at most 2 μSv/h in the surrounding of the building without shielding the roof. For similar geometries the skyshine is negligible for dose rates at the unshielded roof of less than 3 mSv/h (exclusion area).
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Affiliation(s)
- P. Sahre
- Nuclear Engineering and Analytics Rossendorf, Verein für Kernverfahrenstechnik und Analytik Rossendorf e.V. Postf. 510119, 01314 Dresden, Germany
| | - M. Kaden
- Nuclear Engineering and Analytics Rossendorf, Verein für Kernverfahrenstechnik und Analytik Rossendorf e.V. Postf. 510119, 01314 Dresden, Germany
| | | | - J. Pawelke
- Helmholtz-Zentrum Dresden-Rossendorf
- Technische Universität Dresden
- OncoRay Dresden
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Klosterhuis H, Baumgarten E, Beckmann U, Erbstösser S, Lindow B, Naumann B, Widera T, Zander J. [Quality assurance of rehabilitation by the German pension insurance: an overview]. REHABILITATION 2010; 49:356-67. [PMID: 21140319 DOI: 10.1055/s-0030-1268433] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The German pension insurance has in recent years developed a comprehensive programme for quality assurance in rehabilitation, and has implemented the programme into routine practice. Different aspects of rehabilitation are evaluated with differentiated instruments. Issues dealt with inter alia include the quality of rehabilitative care in a narrower sense, the structure and organisation of the rehabilitation centres, as well as quality from the patients' perspective. On the whole, positive results predominate. Big differences in quality however have been found between the rehabilitation centres. The data collections and data evaluations carried out make a continuous process of quality assurance reporting possible for use by rehabilitation centres and pension insurance agencies. This will enable targeted initiatives for quality improvement. The methods and procedures of quality assurance are enhanced at regular intervals, and the scope of quality assurance is extended. Thus, rehab quality assurance is also expanded to cover ambulant rehabilitation or rehabilitation of children and young people.
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Sell JF, Gearba MA, Patterson BM, Genda T, Naumann B, Knize RJ. Enhancement of Rb fine-structure transfer in 4He due to three-body collisions. Opt Lett 2010; 35:2146-2148. [PMID: 20596175 DOI: 10.1364/ol.35.002146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Using ultrafast laser excitation and time-correlated single-photon counting techniques, we have measured the collisional mixing rates between the rubidium 5(2)P fine-structure levels in the presence of (4)He gas. A nonlinear dependence of the mixing rate with (4)He density is observed. We find Rb fine-structure transfer is primarily due to binary collisions at (4)He densities of < or = 10(19) cm(-3), while at greater densities, three-body collisions become significant. We determine a three-body collisional transfer rate coefficient (5(2)P(3/2) --> 5(2)P(1/2)) of 1.25(9)x10(-32) cm(6)/s at 22 degrees C.
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Affiliation(s)
- J F Sell
- Laser and Optics Research Center, U.S. Air Force Academy Department of Physics, USAF Academy, Colorado 80840, USA.
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Ekman CA, Naumann B. ON THE PRESENCE OF MAST CELLS IN THYROID GLANDS FROM GUINEA-PIG AND FROM MAN, UNDER DIFFERENT CONDITIONS. ACTA ACUST UNITED AC 2009; 22:271-7. [DOI: 10.1111/j.1699-0463.1945.tb04063.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Naumann B, Pollmann H, Herrmann FH, Wulff K, Schröder W. Molecular characterization of the novel FX mutation IVS7-1G>A. Hamostaseologie 2008. [DOI: 10.1055/s-0037-1621630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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Grobusch MP, Lell B, Schwarz NG, Gabor J, Dornemann J, Potschke M, Oyakhirome S, Kiessling GC, Necek M, Langin MU, Klein Klouwenberg P, Klopfer A, Naumann B, Altun H, Agnandji ST, Goesch J, Decker M, Salazar CLO, Supan C, Kombila DU, Borchert L, Koster KB, Pongratz P, Adegnika AA, Glasenapp IV, Issifou S, Kremsner PG. Intermittent preventive treatment against malaria in infants in Gabon--a randomized, double-blind, placebo-controlled trial. J Infect Dis 2007; 196:1595-602. [PMID: 18008242 DOI: 10.1086/522160] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2007] [Accepted: 05/30/2007] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Intermittent preventive treatment aims to maximize the protective effects of malaria chemoprophylaxis while minimizing the deleterious effects. METHODS In Gabon, 1189 infants received either sulfadoxine-pyrimethamine (SP; 250 and 12.5 mg, respectively) or placebo at 3, 9, and 15 months of age. Children were actively followed-up until 18 months of age. RESULTS In the intention-to-treat population at 18 months of follow-up, 84 children (17%) in the SP group had > or =1 episode of anemia, versus 108 (21%) in the placebo group (protective efficacy, 22% [95% confidence interval {CI}, -1% to 40%]; P=.06). In the intervention group, there were 66 episodes during 485 person-years at risk, compared with 79 episodes during 497 years in the placebo group (protective efficacy, 17% [95% CI, -24% to 45%; P=.36). The effects were similar at 12 months of follow-up. The study drug was safe and well tolerated. CONCLUSIONS The intervention was efficacious, producing a reduction in risk for anemia but a smaller effect against malaria. It is a valuable additional tool to control malaria in a highly vulnerable age group. Remaining important questions are currently being addressed in further studies. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT00167843.
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Affiliation(s)
- Martin P Grobusch
- Medical Research Unit, Albert Schweitzer Hospital, Lambarene, Gabon.
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Altstadt E, Beckert C, Freiesleben H, Galindo V, Grosse E, Junghans A, Klug J, Naumann B, Schneider S, Schlenk R, Wagner A, Weiss FP. A photo-neutron source for time-of-flight measurements at the radiation source ELBE. ANN NUCL ENERGY 2007. [DOI: 10.1016/j.anucene.2006.11.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
Malignant tumors of the hepatobiliopancreatic system are not curable in > 60%. For this reason, palliation plays an important therapeutic role. Indications are mainly obstructive jaundice, duodenal obstruction and pain. Assessment of the tumor's morphology and resectability is often possible only by surgical exploration. If necessary and feasible, non-curable malignancies are treated synchronously during this operation. In preoperatively proven distant metastases or local non-resectability, interventional procedures are preferred. They are efficient, at least primarily, and mostly correlated with little patient discomfort. A surgical biliary bypass obviously leads to improved long-term palliation. Especially in Klatskin tumors, palliative resection may be useful. Generally the patients benefit from palliation depends on minor therapeutic discomfort and long-lasting control of symptoms.
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Affiliation(s)
- H D Saeger
- Klinik und Poliklinik für Viszeral-, Thorax- und Gefässchirurgie, Universitätsklinikum Carl Gustav Carus, Technischen Universität Dresden
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Ableev VG, Dzhemukhadze S, Naumann B, Nomofilov AA, Piskunov NM, Sharov VI, Shmakov SY, Sitnik IM, Strokovsky EA, Strunov LN, Tesch S, Uzhinskii VV, Zaporozhets SA. Diffraction scattering of alpha-particles on nuclei at 17.9 GeV/c. ACTA ACUST UNITED AC 1991. [DOI: 10.1007/bf01303832] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Schlesinger RB, Naumann B, Chen LC. A system for measurement of radioactive aerosol retention in the lungs of rabbits. Health Phys 1982; 42:73-77. [PMID: 7056651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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