Sensilla on head appendages were studied in detail for the first time in a member of the relict family Hygrobiidae (squeak beetles), closely related to Dytiscidae (diving beetles). Adult and third instar larval stage specimens of Hygrobia hermanni (Fabricius, 1775) were examined using scanning electron microscopy, focusing on antennae, palps and larval mandibles. In total, 37 sensilla subtypes are described, including 22 observed in the adult (basiconica: 3; Böhm's bristles: 2; circumvallate sensilla: 2; coeloconica: 10; ovoid placodea: 3; digitiform placodea: 2) and 16 in the larva (basiconica: 4; campaniformia: 1; chaetica: 4; coeloconica: 5; trichodea: 1; unnamed: 1).
View Article and Find Full Text PDFObjective: To identify correlations between disease recurrence and adherence to NCCN posttreatment surveillance guidelines in patients who develop recurrent uterine cancer.
Methods: Retrospective analysis identified patients (n = 60) with recurrent uterine cancer and at least one surveillance visit with a gynecologic oncologist between 2011 and 2020. Adherence to NCCN guidelines and details of recurrence were recorded.
Objective: To determine whether Black race is associated with treatment and survival among women with low-risk endometrial cancer.
Methods: Black and White women with Stage IA grade 1-2 endometrioid endometrial carcinoma diagnosed from 2010 to 2016 in the SEER 18 dataset were identified (n = 23,431), and clinical and socioeconomic attributes obtained. Five-year cancer-specific survival (CSS) and relative survival (RS) were calculated using SEER*Stat 8.
Water beetles of the families Gyrinidae, Haliplidae, Noteridae, and Dytiscidae (aquatic Adephaga) of the Makay in central-western Madagascar were surveyed in three campaigns during the years 2016-2018. A total of 74 species was collected from 62 sampling sites, all except one being newly recorded from the Makay. ( group) and ( group) (Dytiscidae, Copelatinae) are described and their habitus and male genitalia are illustrated.
View Article and Find Full Text PDFFour new Laccophilus species are described from Madagascar, three belonging to the L. alluaudi-group (Laccophilus leguyaderi sp. nov.
View Article and Find Full Text PDFMegadytes (Bifurcitus) ducalis Sharp, 1882 is the largest diving beetle in the world and has been considered a candidate for the world's rarest insect (Jones 2010). It was described from "Brazil", is only known from the male holotype in the Natural History Museum (London), and typically thought to be extinct. Here we report the finding of 10 additional specimens, all collected at the end of the 19th century, which were discovered incidentally in different historical collections, including drawers with unsorted diving beetle accessions of the Muséum National d'Histoire Naturelle (Paris).
View Article and Find Full Text PDFThe tentacular system of Clytia hemisphaerica medusa (Cnidaria, Hydrozoa) has recently emerged as a promising experimental model to tackle the developmental mechanisms that regulate cell lineage progression in an early-diverging animal phylum. From a population of proximal stem cells, the successive steps of tentacle stinging cell (nematocyte) elaboration, are spatially ordered along a "cellular conveyor belt". Furthermore, the C.
View Article and Find Full Text PDFJellyfish (medusae) are a distinctive life-cycle stage of medusozoan cnidarians. They are major marine predators, with integrated neurosensory, muscular and organ systems. The genetic foundations of this complex form are largely unknown.
View Article and Find Full Text PDFThe species of the genus Copelatus Erichson, 1832 occurring in the Dominican Republic are reviewed. Five species are recorded, with recent collecting data provided for four of them. Copelatus martini sp.
View Article and Find Full Text PDFCanthyporus reebae sp. nov. is described from the south-eastern part of the Itremo mountain range and from the Andringitra massif in central eastern Madagascar.
View Article and Find Full Text PDFResolving the early diversification of animal lineages has proven difficult, even using genome-scale datasets. Several phylogenomic studies have supported the classical scenario in which sponges (Porifera) are the sister group to all other animals ("Porifera-sister" hypothesis), consistent with a single origin of the gut, nerve cells, and muscle cells in the stem lineage of eumetazoans (bilaterians + ctenophores + cnidarians). In contrast, several other studies have recovered an alternative topology in which ctenophores are the sister group to all other animals (including sponges).
View Article and Find Full Text PDFWiley Interdiscip Rev Dev Biol
January 2017
Neurogenesis initiates during early development and it continues through later developmental stages and in adult animals to enable expansion, remodeling, and homeostasis of the nervous system. The generation of nerve cells has been analyzed in detail in few bilaterian model organisms, leaving open many questions about the evolution of this process. As the sister group to bilaterians, cnidarians occupy an informative phylogenetic position to address the early evolution of cellular and molecular aspects of neurogenesis and to understand common principles of neural development.
View Article and Find Full Text PDFCtenophores are non-bilaterian metazoans of uncertain phylogenetic position, some recent studies placing them as sister-group to all other animals whereas others suggest this placement is artefactual and ctenophores are more closely allied with cnidarians and bilaterians, with which they share nerve cells, muscles and gut. Available information about developmental genes and their expression and function in ctenophores is reviewed. These data not only unveil some conserved aspects of molecular developmental mechanisms with other basal metazoan lineages, but also can be expected to enlighten the genomic and molecular bases of the evolution of ctenophore-specific traits, including their unique embryonic development, complex anatomy and high cell type diversity.
View Article and Find Full Text PDFBackground: The Hippo pathway regulates growth rate and organ size in fly and mouse, notably through control of cell proliferation. Molecular interactions at the heart of this pathway are known to have originated in the unicellular ancestry of metazoans. They notably involve a cascade of phosphorylations triggered by the kinase Hippo, with subsequent nuclear to cytoplasmic shift of Yorkie localisation, preventing its binding to the transcription factor Scalloped, thereby silencing proliferation genes.
View Article and Find Full Text PDFStem cells are pivotal for development and tissue homeostasis of multicellular animals, and the quest for a gene toolkit associated with the emergence of stem cells in a common ancestor of all metazoans remains a major challenge for evolutionary biology. We reconstructed the conserved gene repertoire of animal stem cells by transcriptomic profiling of totipotent archeocytes in the demosponge Ephydatia fluviatilis and by tracing shared molecular signatures with flatworm and Hydra stem cells. Phylostratigraphy analyses indicated that most of these stem-cell genes predate animal origin, with only few metazoan innovations, notably including several partners of the Piwi machinery known to promote genome stability.
View Article and Find Full Text PDFThe genus Notomicrus Sharp, 1882 is recorded from Guadeloupe for the first time. Examination of recently collected material revealed the presence of four species, of which three are described as new species so far endemic to Guadeloupe. Notomicrus sabrouxi sp.
View Article and Find Full Text PDFCtenophores are a phylum of non-bilaterian marine (mostly planktonic) animals, characterised by several unique synapomorphies (e.g., comb rows, apical organ).
View Article and Find Full Text PDFEcological developmental biology (eco-devo) explores the mechanistic relationships between the processes of individual development and environmental factors. Recent studies imply that some of these relationships have deep evolutionary origins, and may even pre-date the divergences of the simplest extant animals, including cnidarians and sponges. Development of these early diverging metazoans is often sensitive to environmental factors, and these interactions occur in the context of conserved signaling pathways and mechanisms of tissue homeostasis whose detailed molecular logic remain elusive.
View Article and Find Full Text PDFHydroporus rifensis sp. n. is described from Central Rif in northern Morocco.
View Article and Find Full Text PDFSignalling through the Wnt family of secreted proteins originated in a common metazoan ancestor and greatly influenced the evolution of animal body plans. In bilaterians, Wnt signalling plays multiple fundamental roles during embryonic development and in adult tissues, notably in axial patterning, neural development and stem cell regulation. Studies in various cnidarian species have particularly highlighted the evolutionarily conserved role of the Wnt/β-catenin pathway in specification and patterning of the primary embryonic axis.
View Article and Find Full Text PDFHydroporus galloprovincialis sp. n. is described from Jouques, north-east of Aix-en-Provence in south-eastern France (Provence).
View Article and Find Full Text PDFBackground: Myosin II (or Myosin Heavy Chain II, MHCII) is a family of molecular motors involved in the contractile activity of animal muscle cells but also in various other cellular processes in non-muscle cells. Previous phylogenetic analyses of bilaterian MHCII genes identified two main clades associated respectively with smooth/non-muscle cells (MHCIIa) and striated muscle cells (MHCIIb). Muscle cells are generally thought to have originated only once in ancient animal history, and decisive insights about their early evolution are expected to come from expression studies of Myosin II genes in the two non-bilaterian phyla that possess muscles, the Cnidaria and Ctenophora.
View Article and Find Full Text PDFThe separation of the germ line from the soma is a classic concept in animal biology, and depending on species is thought to involve fate determination either by maternally localized germ plasm ("preformation" or "maternal inheritance") or by inductive signaling (classically termed "epigenesis" or "zygotic induction"). The latter mechanism is generally considered to operate in non-bilaterian organisms such as cnidarians and sponges, in which germ cell fate is determined at adult stages from multipotent stem cells. We have found in the hydrozoan cnidarian Clytia hemisphaerica that the multipotent "interstitial" cells (i-cells) in larvae and adult medusae, from which germ cells derive, express a set of conserved germ cell markers: Vasa, Nanos1, Piwi and PL10.
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