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27872. Ultrastructural study of Sarcocystis muriviperae development in the intestine of its snake hosts
- Creator:
- Paperna, Ilan and Finkelman, Simcha
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Sarcocystis muriviperae, Vipera palaestinae, Coluber jugularis, ultrastructure, endogenous development, microgamonts, macrogamonts, and oocysts
- Language:
- English
- Description:
- The ultrastructure of the endogenous stages - merozoites, microgamonts, macrogamonts and oocysts, of Sarcocystis muriviperae from the snakes Vipera palaestinae and Coluber jugularis is described. Snakes were infected via white mice fed on sporocysts obtained from naturally infected snakes of the same species. Snakes examined 4 days post-infection contained only young and premature gamonts. Infection in snakes sacrificed on day 7 post-infection consisted predominantly of mature microgamonts and macrogamonts; snakes examined on day 10 post-infection revealed only oocysts. The fine structure of the endogenous stages from the two snakes, including size and contents of the wall-forming bodies, was identical, confirming their suggested conspecificity. Observed endogenous stages also conformed in their major details with the same developmental stages of other Sarcocystis species studied from other snakes and mammalian definitive hosts and from in vitro culture. However, they differed from the latter in size and contents of the wall-forming bodies. The observed fertilization process was reminiscent of that described earlier in S. bovicanis.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27873. Ultrastructural study of tergal and posterior sternal glands in Prorhinotermes simplex (Isoptera: Rhinotermitidae)
- Creator:
- Šobotnik, Jan, Weyda, František, and Hanus, Robert
- Type:
- article, model:article, and TEXT
- Subject:
- Ultrastructure, tergal gland, posterior sternal gland, secretory cell class 2, termite, Isoptera, Rhinotermitidae, Prorhinotermes simplex, and imagoes
- Language:
- English
- Description:
- In Prorhinotermes simplex, tergal glands are present on the last three tergites (from the 8th to the 10th) in imagoes of both sexes. In addition, males possess posterior sternal glands of the same structure on sternites 8 and 9. The tergal and the posterior sternal glands consist of four cell types: class 1 and class 2 secretory cells, and class 3 cells with corresponding canal cells. The cytoplasm of class 1 cells contains smooth endoplasmic reticulum, elongated mitochondria and numerous microtubules. Apical parts of these cells are formed by dense and long microvilli with a central ductule. Class 2 cells contain predominantly lucent vacuoles (in females) or lipid droplets (in males). The structure of class 3 cells does not differ from class 3 cells found in other body parts.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27874. Ultrastructure and chemical composition of the proboscis hooks of Acanthocephalus lucii (Müller, 1776) (Acanthocephala: Palaeacanthocephala) using X-ray elemental analysis
- Creator:
- Brázová, Tímea, Poddubnaya, Larisa G., Miss, Noemí Ramírez, and Hanzelová, Vladimíra
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- scanning electron microscopy, energy-dispersive X-ray analysis, transmission electron microscopy, tegument, and hooks
- Language:
- English
- Description:
- The ultrastructure and chemical composition of the proboscis hooks and surrounding tegument of Acanthocephalus lucii (Müller, 1776), a parasite of European perch, Perca fluviatilis Linnaeus, were examined using scanning (SEM) and transmission (TEM) electron microscopy and X-ray microanalysis (EDXA). The blade of middle hooks consists of three layers: an outer homogeneous layer, an inner heterogeneous layer and a central core. TEM observation revealed the presence of hollow tubes, which spaced the central core; fibrous inner hook layer surrounded by an electron-dense margin and the basal tegumental layer filled with electron-dense bodies and outer layer. We found for the first time that the so-called ''epidermal covering'' surrounding of the exposed hook blade (outer hook layer) is a modified striped portion of the tegumental layer and there are no special contact sites between these two morphologically different structures, i.e. striped layer of the syncytial tegument and following proper outer hook layer, which is a homogeneous, moderately electron-dense layer of ~0.3 µm in thickness. The hook root is embedded into subtegumental fibrous layer. X-ray microanalysis of both the surface and internal parts of A. lucii hooks demonstrated the presence of calcium, magnesium, phosphorus and sulphur. The highest concentration of sulphur was recorded at the tip of hooks, whereas the middle part of the hooks was most rich in calcium, phosphorus and magnesium. The proximal part of the hooks contained lower concentrations of sulphur, calcium and phosphorus. In the proboscis tegument, only two elements, calcium and silicon, were found. The differences observed in the chemical composition of the hook ''epidermal covering'' and the proboscis tegument support our ultrastructural findings that the hook tegumental covering is a modified structure compared with that of the general proboscis tegument.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27875. Ultrastructure and localisation of late-sporogonic developmental stages of Sphaerospora ranae (Myxosporea: Sphaerosporidae)
- Creator:
- Jirků, Miloslav and Bartošová-Sojková, Pavla
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Amphibia, Anura, Europe, kidneys, myxospore, Myxozoa, Rana, sporogony, synchronisation, and in situ hybridisation
- Language:
- English
- Description:
- Data on external ultrastructure of myxospores and internal ultrastructure of advanced pseudoplasmodia and myxospores of topotypic samples of Sphaerospora ranae (Morelle, 1929) from Rana dalmatina Bonaparte are provided, together with in situ hybridisation results. In both frogs examined, the infection was restricted to renal tubules and corpuscles. The infection site restriction was confirmed by light and transmission electron microscopy, as well as by in situ hybridisation. In addition, large myxospore masses measuring up to 500 μm were detected in seminal vesicles. Only late-sporogonic stages, i.e. pseudoplasmodia harbouring immature and/or mature myxospores, were observed and analysed. Scanning electron microscopy revealed that spores have smooth surface with exception of posterior valvular bulges, which possess numerous outwards opening internal canals. As revealed by both scanning and transmission electron microscopy, the canals are continuous invaginations of the outer spore surface. Myxospores of S. ranae are characterised by the presence of two uninucleate sporoplasms, bilayered polar capsules, S/H-shaped polar filaments in transversal section and multilayered polar filament eversion pole plugging complex. Ultrastructural observations are discussed in the context of available data for other species of Sphaerospora sensu stricto and apparent synchronisation of myxospore shedding with a brief aquatic breeding phase of vertebrate intermediate host is highlighted.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27876. Ultrastructure and molecular phylogeny of four new species of monoxenous trypanosomatids from flies (Diptera: Brachycera) with redefinition of the genus Wallaceina
- Creator:
- Yurchenko, Vyacheslav, Votýpka, Jan, Tesařová, Martina, Klepetková, Helena, Kraeva, Natalya, Jirků, Milan, and Lukeš, Julius
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Kinetoplastida, Trypanosomatidae, monoxenous kientoplastids, Leishmaniinae, molecular taxonomy, and phylogeny
- Language:
- English
- Description:
- Four new species of monoxenous kinetoplastid parasites are described from Brachycera flies, namely Wallaceina raviniae Votýpka et Lukeš, 2014 and Crithidia otongatchiensis Votýpka et Lukeš, 2014 from Ecuador, Leptomonas moramango Votýpka et Lukeš, 2014 from Madagascar, and Crithidia pragensis Votýpka, Klepetková et Lukeš, 2014 from the Czech Republic. The new species are described here based on sequence analysis of their spliced leader (SL) RNA, glycosomal glyceraldehyde 3-phosphate dehydrogenase (gGAPDH) and small subunit (SSU) rRNA genes, as well as their morphology and ultrastructure. High-pressure freezing and Bernhard's EDTA regressive staining, used for the first time for monoxenous (one host) trypanosomatids, revealed the presence of viral particles with cytosolic localization in one and unique mitochondrial localization in another species. In accordance with previous observations, our results emphasize a discrepancy between morphology and molecular taxonomy of the family Trypanosomatidae. All four newly described species are represented by typical morphotypes (mainly choano- and promastigotes) and are virtually indistinguishable from other monoxenous trypanosomatids by morphology. Nevertheless, they all differ in their phylogenetic affinities. Whereas three of them grouped within the recently defined subfamily Leishmaniinae, which includes numerous representatives of the genera Leishmania Ross, 1903, Crithidia Léger, 1902 and Leptomonas Kent, 1880, the fourth species clusters together with the ''collosoma'' clade (named after ''Leptomonas'' collosoma Wallace, Clark, Dyer et Collins, 1960). Here we demonstrate that the ''collosoma'' group represents the elusive genus Wallaceina Podlipaev, Frolov et Kolesnikov, 1999. We redefine this genus in molecular terms based on similarities of the respective molecular markers and propose to use this taxon name for the group of species of the ''collosoma'' clade.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27877. Ultrastructure and phylogeny of Glugea nagelia sp. n. (Microsporidia: Glugeidae), infecting the intestinal wall of the yellowfin hind, Cephalopholis hemistiktos (Actinopterygii: Serranidae), from the Red Sea
- Creator:
- Abdel-Baki, Abdel-Azeem S, Al-Quraishy, Saleh, Rocha, Sónia, Dkhil, Mohamed A, Casal, Graça, and Azevedo, Carlos
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitické organismy, parasitic organisms, fish parasite, microsporidian, fine structure, rRNA genes, 2, and 59
- Language:
- English
- Description:
- A new microsporidian species of the genus Glugea Thélohan, 1891 parasitising the marine teleost fish Cephalopholis hemistiktos Rüppell, collected from the Red Sea in Saudi Arabia, is described on the basis of microscopic and molecular procedures. Spherical and whitish xenoma were observed adhering to the intestinal wall. The numerous spores contained within these xenoma, were ovoid to pyriform and measured 4.3-6.0 µm (5.1 µm) in length and 1.8-2.9 µm (2.2 µm) in width. The spore's wall was composed of two thick layers, which were thinner in the area contacting the anchoring disk. The latter appeared at the spore's anterior pole, in an eccentric position to the longitudinal axis. A lamellar polaroplast surrounded the uncoiled portion of the polar filament projected to the basal region of the spore, giving rise to 26-29 turns with winding from the base to the anterior zone of the spore. The posterior vacuole, located at the spore's posterior pole, and surrounded by the polar filament coils, was irregular and composed of light material. Molecular analysis of the rRNA genes, including the ITS region, was performed using maximum parsimony, neighbour-joining and maximum likelihood methods. The ultrastructural features observed, combined with the phylogenetic data analysed, suggest this parasite to be a new species of the genus Glugea. This is the first species of this genus to be reported from Saudi Arabia and is herein named Glugea nagelia sp. n., Abdel-Azeem S. Abdel-Baki, Saleh Al-Quraishy, Sónia Rocha, Mohamed A. Dkhil, Graça Casal, Carlos Azevedo., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27878. Ultrastructure of Archigetes sieboldi (Cestoda: Caryophyllidea): relationship between progenesis, development and evolution
- Creator:
- Poddubnaya, Larisa G., Mackiewicz, John S., and Kuperman, Boris I.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Archigetes sieboldi, ultrastructure, progenesis, and evolution
- Language:
- English
- Description:
- Ultrastructural characteristics of progenetic and monoxenic Archigetes sieboldi Leuckart, 1878 from the oligochaete Limnodrilus hoffmeisteri Claparède are described. Our observations demonstrate that progenetic Archigetes sieboldi shares characteristics of both larval (progenetic) and adult stages. The primary larval characteristics are: the presence of a cercomer; a surface filamentous coat covering the whole worm; the presence of the penetration glands and the absence of tegumental ones; wide sarcoplasmic processes connecting the circular and longitudinal external tegumental muscles; the absence of the dense homogenous zone of the basal lamina beneath the epithelial cytoplasm of all reproductive organs and ducts; non-functional gonopores; and an orthogonal plan of nervous system with three pairs of longitudinal nerve trunks. The principle adult characteristics are: oogenesis, spermiogenesis and vitellogenesis that produce fertilized eggs; the uterine glands; a well-developed longitudinal tegumental muscle layer between tegumental cytons; and the presence of different microtriches. As a result of this progenetic development there has been a secondary reduction in the life cycle of A. sieboldi. It is postulated that a similar process of progenesis may have played a major role in the early evolution of the Caryophyllidea by first appearing in a plerocercoid stage of an ancestral strobilate cestode from fish.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27879. Ultrastructure of developmental stages of Hemolivia mariae (Apicomplexa: Haemogregarinidae), natural parasite of the Australian sleepy lizard, in experimentally infected deviant hosts
- Creator:
- Paperna, Ilan and Smallridge, Catherine J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Haemogregarinidae, Hemolivia mariae, ultrastructure, merogony, gametocytes, wall development, and osmiophilic bodies
- Language:
- English
- Description:
- Mabuya vitatta (Olivier) (Scincidae) and Agama stellio (L.) (Agamidae) were infected with Hemolivia mariae Smallridge et Paperna, 1997 by ingestion of tick viscera from Amblyomma limbatum Neumann, fed as nymphs on naturally infected Australian sleepy lizards, Tiliqua rugosa Gray. The unnatural infection apparently interfered with the developmental schedule of the parasites. Transmission electron microscopic images of merogonic stages were obtained, as well as images of early developing gametocytes. Tissue and intraerythrocytic meronts were bound by a hardened wall. Intraerythrocytic gametocytes were lodged in a parasitophorous vacuole, which was filled with granular material, and were bound by a two-membrane wall. Small and large osmiophilic bodies were located in a sub-pellicular position. With differentiation, the wall membranes tightened with the parasitophorous vacuole wall, and the osmiophilic bodies disappeared. The outer parasite membrane consolidated into a thick encasing with distinct sutures. Late infection in A. stellio comprised gametocytes only.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27880. Ultrastructure of glands in a scutaricllid (Platyhelminthes) and possible phylogenetic implications
- Creator:
- Iomini, Carlo, Ferraguti, Marco, and Justine, Jean-Lou
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Platyhelminthes, Temnocephalida, Scutariellidae, ultrastructure, and glands
- Language:
- English
- Description:
- Subepidermal glands of the body of Troglocaridicola sp. (from the cavemicolous shrimp Troglocaris sp. in eastern Italy) were observed by transmission electron microscopy. The reservoir and duct of the glands arc lined with longitudinal microlubulcs. Membrane-bound granules inside the gland show a distinctive pattern: they contain fibres, 18 nm in diameter, regularly arranged in bundles with a 5 nm space between libres. From a survey of the available literature on glands of Platyhelminthes, it is concluded that this structure is known only in this species. Glands with regularly arranged 18 nm fibres, if characteristic for the Scutariellidae, could be considered an autapomorphy of this family, distinguishing it from other members of the Temnocephalida.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public