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1

Ultrastructure of spermatogenesis of the anoplocephalid cestode Gallegoides arfaai [Mobedi et Ghadirian, 1977] Tenora et Mas-Coma, 1978

100%
Miquel J., Swiderski Z., Mlocicki D., Eira C., Marchand B.
Acta Parasitologica
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2005
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tom 50
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nr 2
Spermatogenesis in Gallegoides arfaai is similar to that described for other cestode species. Six incomplete synchronic cytokineses occur: four mitotic and two meiotic cell divisions. The primary spermatogonium divides forming two secondary spermatogonia. All further divisions occur simultaneously, resulting in a rosette of four tertiary, then eight quaternary spermatogonia and sixteen primary spermatocytes. The first meiotic division forms thirty-two secondary spermatocytes and after the second meiotic division sixty-four spermatids are formed. Spermiogenesis begins with the formation of a differentiation zone in the form of a conical projection of cytoplasm delimited by a ring of arching membranes. Within this area there are two centrioles, a centriolar adjunct and vestigial striated rootlets. During spermiogenesis, only one of the centrioles develops an axoneme that grows directly into the cytoplasmic extension. The other centriole remains oriented in a cytoplasmic bud and posteriorly aborts. The nucleus elongates and moves into the cytoplasmic extension. Granular material present in each sperm originates from electron-dense material present in the periphery of the spermatid. In the final stage of spermiogenesis two crest-like bodies appear at the Bâse of the spermatid. Finally, the ring of arching membranes constricts and the young spermatozoon detaches from the residual cytoplasm. In order to increase homogeneity in the designation of the non-typical striated rootlets previously described, in this study we propose to group them under the common designation of "vestigial striated rootlets" and its importance is discussed according to previous findings of related structures in other cyclophyllideans.
2
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Ultrastructure of the tegument of the anoplocephalid cestode Mosgovoyia ctenoides [Railliet, 1890] Beveridge, 1978

100%
Mlocicki D., Eira C., Zebrowska J., Miquel J., Swiderski Z.
Wiadomości Parazytologiczne
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2004
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tom 50
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nr 3
3

Fertilization in the cestode Gallegoides arfaai [Mobedi et Ghadirian, 1977] Tenora et Mas-Coma, 1978 [Cyclophyllidea, Anoplocephalidae]

84%
Swiderski Z., Conn D. B., Miquel J., Mlocicki D.
Acta Parasitologica
|
2004
|
tom 49
|
nr 2
Fertilization in the anoplocephalid cestode Gallegoides arfaai with uniflagellate spermatozoa was examined by means of light and transmission electron microscopy. Fertilization in this species occurs in the oviduct lumen or in the fertilization canal proximal to the ootype, where the formation of the embryonic capsule precludes sperm contact with the oocyte. Cortical granules are not present in the cytoplasm of oocytes of this species. However, two other types of large bodies containing granular material, one of homogeneous moderate electron density and one of heterogeneous moderate electron density, are present in the perinuclear cytoplasm of the oocytes. Spermatozoa coil spirally around the oocytes and syngamy occurs by lateral fusion of oocyte and sperm plasma membranes. In the ootype, one vitellocyte associates with the fertilized oocyte, forming a membranous capsule which encloses both cell types. In this stage, spirally coiled sperm flagella adhere partly to the external oocyte surfaces, and partially enter into the perinuclear cytoplasm. Usually, several loops of the spermatozoon occur within the oocyte cytoplasm. The electron-dense sperm nucleus becomes progressively electron-lucent within the oocyte cytoplasm after entry. Simultaneously with chromatin decondensation, the elongate sperm nucleus changes shape, forming a spherical male pronucleus, which attains the size of the female pronucleus. Cleavage begins immediately after pronuclear fusion.
4

Ultrastructure of oncospheral hook formation in the cestode Mosgovoyia ctenoides [Railliet, 1890] Beveridge, 1978 [Cyclophyllidea, Anoplocephalidae]

84%
Mlocicki D., Swiderski Z., Conn D. B., Eira C., Miquel J., Baranowska-Korczyc A.
Acta Parasitologica
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2005
|
tom 50
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nr 2
The ultrastructure of oncospheral hook formation in the anoplocephalid cestode Mosgovoyia ctenoides (Railliet, 1890) Beveridge, 1978, is described. The hook morphogenesis takes place inside the six symmetrically arranged hook-forming cells, the oncoblasts. They show characteristic large nuclei of semilunar shape, localized at one pole of the embryo. At the beginning of the hook formation, the "hook-forming centre" appears in the cytoplasmic part of each oncoblast. It consists of numerous free ribosomes and polyribosomes surrounded by several mitochondria and Golgi complexes. The hook-forming centre is involved in synthesis of an electron-dense, undifferentiated hook primordium, which undergoes progressive differentiation and elongation into the fully developed hook. A fully formed oncospheral hook consists of the three parts: blade, shank, and base. Each hook, at the site of its protrusion from the oncosphere, is surrounded by two electron-dense rings interconnected by a circular septate junction. The hook material consists of two or three layers that differ in electron density: (1) a moderately electron-dense core, (2) a middle layer of low electron density, and (3) a highly osmiophilic cortex. Wide bands of hook muscles are attached to the basal and collar parts of the hook. The hook blades project outside of the oncospheral body into a large cavity delimited by the hook region membrane attached at this pole directly to the oncospheral surface. In the fully developed oncosphere of M. ctenoides, the three pairs of oncospheral hooks and their muscles form a complex "hook muscle system", responsible for coordinated hook action. The differentiation and ultrastructure of oncospheral hooks in the oncospheres of M. ctenoides are compared to those described in other cestode species.
5

Taxonomy and genetic divergence of Paranoplocephala kalelai [Tenora, Haukisalmi et Henttonen, 1985] [Cestoda, Anoplocephalidae] in the grey-sided vole Myodes rufocanus in Northern Fennoscandia

67%
Haukisalmi V., Hardman L. M., Niemimaa J., Henttonen H.
Acta Parasitologica
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2007
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tom 52
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nr 4
Paranoplocephala kalelai (Tenora, Haukisalmi et Henttonen, 1985) is an anoplocephalid cestode that primarily parasitizes the grey-sided vole Myodes rufocanus (syn. Clethrionomys rufocanus) in northern Fennoscandia. In a preliminary molecular phylogenetic analysis, the cytochrome oxidase I (mtDNA) sequences of P. kalelai formed two divergent sublineages originating from two different localities in northern Finland and northern Norway. The present data confirm the existence of two strongly supported clades and show that their geographic distributions are overlapping in northernmost Finland. Relatively deep genetic divergence and coexistence of the two main clades at one of the localities suggest that the material may include two biological species. However, because the specimens representing the two mtDNA clades of P. kalelai are not morphometrically sufficiently differentiated and because the mtDNA clade of the specimens from the type locality is unknown, they are not assigned to different species. Comparison with the existing phylogeographic data of M. rufocanus suggests that the genetic structure of this host-specific cestode reflects the glacial and post-glacial history of its primary host. A redescription is presented for P. kalelai.
6

Ultrastructural study of the embryonic development of the anoplocephalid cestode Anoplocephaloides dentata, an intestinal parasite of Arvicolidae rodents. I. Egg envelope formation

67%
Swiderski Z., Ndiaye P. I., Tkach V., Miquel J., Marchand B., Chomicz L., Sereda M. J.
Acta Parasitologica
|
2001
|
tom 46
|
nr 3
7

Ultrastructural study of the embryonic development of the anoplocephalid cestode Anoplocephaloides dentata, an intestinal parasite of Arvicolidae rodents. II. Differentiation and cellular organisation of the oncosphere

67%
Swiderski Z., Ndiaye P. I., Miquel J., Tkach V., Marchand B., Chomicz L., Grytner-Ziecina B., Sereda M. J.
Acta Parasitologica
|
2001
|
tom 46
|
nr 4
8

Anoplocephalid cestodes of wood rats [Neotoma spp.] in the Western U.S.A.

67%
Haukisalmi V., Rausch R. L.
Acta Parasitologica
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2006
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tom 51
|
nr 2
This study reviews the taxonomy of anoplocephaline cestodes of wood rats, Neotoma cinerea, N. fuscipes and N. mexicana (Sigmodontinae) in the western and south-western U.S.A. The anoplocephaline fauna included five species, only one of which, Andrya neotomae Voge, 1946, was relatively common and occurred in all three host species. Other species were Paranoplocephala freemani Haukisalmi, Henttonen et Hardman, 2006, P. primordialis (Douthitt, 1915), both host-generalist species of North American rodents, and two apparently undescribed species of Paranoplocephala s. str. Aprostatandrya octodonensis Babero et Cattan, 1975 from the indigenous South American rodent Octodon degus is regarded as a junior synonym of A. neotomae. A redescription is provided for A. neotomae.
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