Wyniki wyszukiwania - Biblioteka Nauki

1

Spermatological characteristics of the enigmatic monogenean Dictyocotyle coeliaca Nybelin, 1941 (Monopisthocotylea: Monocotylidae) reveal possible adaptation to endoparasitism

100%

Brunanska M. , Mackiewicz J. S. , Poddubnaya L. G.

Acta Parasitologica

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2017

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tom 62

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nr 1

2

Comparative ultrastructure of mature spermatozoa in Proteocephalidean cestodes, parasites of freshwater fish

100%

Brunanska M. , Scholz T. , Ibraheem M. H.

Wiadomości Parazytologiczne. Suplement

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2004

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tom 50

3

Ultrastructure of the vitellarium in the digeneans Phyllodistomum angulatum (Plagiorchiida, Gorgoderidae) and Azygia lucii (Strigeida, Azygiidae)

100%

Poddubnaya L. G. , Brunanska M. , Swiderski Z. , Gibson D. I.

Acta Parasitologica

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2012

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tom 57

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nr 3

EN

Fine structural features of the vitellarium of two digeneans, Phyllodistomum angulatum and Azygia lucii, are documented and compared with those of other digenean species. The cytodifferentiation of immature vitelline cells (vitellocytes) assumes the production and subsequent accumulation in their cytoplasm of several inclusions. Mature vitelline cells of P. angulatum are characterized by the presence of vitelline clusters (∼2.7 μm in diameter, with ∼100 vitelline globules of ∼0.35 μm in diameter) and osmiophobic, saturated lipid droplets (∼2-3 μm in diameter), and in A. lucii vitelline clusters of the same diameter include much fewer vitelline globules (∼50 globules of ∼0.5 μm in diameter), osmiophilic lipid droplets and α-glycogen. In both P. angulatum and A. lucii, interstitial cells are also present within the vitellarium. Two types of contact sites (septate and tight junctions) between adjoining interstitial cells also occur in both digenean species. Judging from the present and previous ultrastructural studies, it is suggested that there are three potential discriminatory characters of the digenean vitellarium (the number of different types of cell components within the vitellarium, the presence and type of junctional complexes between these cells, and the isolation of the vitellarium from the surrounding tissue) which may prove useful for a better understanding of the biology and evolutionary history of the different digenean groups.

4

Ultrastructure of the oncospheral envelopes in the pseudophyllidean cestode Eubothrium salvelini [Schrank, 1790]

100%

Swiderski Z. , Brunanska M. , Mlocicki D. , Conn D. B.

Acta Parasitologica

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2005

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tom 50

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nr 4

EN

The aim of this study is to describe the ultrastructure of oncospheral envelopes in the pseudophyllidean cestode Eubothrium salvelini, a parasite of salmonid fishes. Our results indicate that the eggs of E. salvelini differ in their ultrastructure from those of the majority of the Pseudophyllidea. The entire embryonic development, including differentiation of the mature, infective oncosphere of E. salvelini takes place in the uterus and not in the aquatic environment, as is common for other pseudophyllideans. Egg maturation is not simultaneous; together with mature eggs containing fully differentiated oncospheres, can be found numerous small immature, nonfertilized and nonviable abortive eggs. The normally developing eggs of E. salvelini are large, oval and nonoperculated. Three envelopes surround the infective hexacanths: (1) the eggshell; (2) the outer envelope originating from macromere fusion; (3) the inner envelope formed by numerous mesomeres which usually persist in the mature eggs. Our observations confirm that both the outer and the inner envelopes of E. salvelini eggs are cellular in origin and syncytial in nature. The typical oncospheral membrane was not observed in this species. New data on the origin and ultrastructure of oncospheral envelopes may present useful criteria for phylogenetic analysis of lower cestodes. Ontogenetic characters, such as ultrastructural aspect of morphogenesis of infective larval stages, are proposed as phylogenetic indicators in studies of cestode evolution.

5

Cytochemical and ultrastructural study on vitellogenesis in caryophyllidean cestode Khawia armeniaca [Cholodkovski, 1915]

100%

Swiderski Z. , Brunanska M. , Poddubnaya L. G. , Mackiewicz J. S.

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nr 1

EN

Vitellogenesis in Khaxvia armeniaca was examined by means of transmission electron microscopy (TEM) and cytochemical staining with periodic acid-thiosemicarbazide-silver proteinate (PA-TSC-SP) for specific detection of glycogen at the ultrastructural level. Mature vitelline follicles consist of cells in various stages of development, progressing from immature cells of gonial type near the periphery to mature vitellocytes towards the centre. Maturation of vitelline cells is characterized by: (1) increase in cell volume; (2) increase in nuclear surface area restoring the N/C ratio; (3) nucleolar transformation; (4) extensive development of large parallel cisternae of GER, the shell-protein producing units; (5) development of Golgi complexes engaged in shell-granule/shell-globule vitelline material formation and package; (6) formation and storage of glycogen in the cytoplasm; (7) simultaneous, independent formation and storage of intranuclear glycogen; (8) continuous fusion of small shell-granules into larger shell-globules that fuse into large shell-globule clusters with a progressive increase in the number and size of the latter; and (9) degeneration of GER in the medial layer of vitellocyte cytoplasm with degenerative changes and accumulation of glycogen and shell-globule clusters within the cytoplasm, associated with a massive accumulation of glycogen in the nucleus. The functional significance of the large amount of nuclear and cytoplasmic glycogen and numerous shell-globule clusters is analysed. The ultrastructural aspect of vitellogenesis is compared with that in other monozoic and polyzoic cestodes. Conclusions concerning the interrelationships of vitellogenesis patterns and ultrastructural cytochemistry of mature vitellocytes to the various types of embryogenesis, are drawn and discussed.

6

Ultrastructural studies on the reproductive system of progenetic Diplocotyle olrikii [Cestoda, Spathebothriidea]: Ovarian tissue

100%

Poddubnaya L. G. , Mackiewicz J. S. , Brunanska M. , Scholz T.

Acta Parasitologica

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2005

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tom 50

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nr 3

EN

The ultrastructure of the ovary and oogenesis are described from the immature and sexually mature female reproductive system of the progenetic spathebothriidean tapeworm, Diplocotyle olrikii from the body cavity of Gammarus oceanicus. Two types of cells are described: germinal (oogonia, oocytes) and interstitial. A comparison is made of the fine structure of oogonia, early and advanced maturing oocytes and mature oocytes. Two types of inclusions, cortical granules and lipid droplets, are produced by maturing oocytes, and remain in the cytoplasm of mature oocytes within the ovovitelline duct lumen while only lipid droplets are evident in the oocyte cytoplasm of intrauterine eggs. The fate and possible functions of both inclusions are discussed. The interstitial component of the ovary is a syncytium. The maturing oocyte surface is prolonged into lamellae, forming a lamellar mesh with adjacent germ cells and close association of interstitial mitochondria. Deep invaginations of the ovarian basement layer between numerous folds of ovarian lobules facilitate close contact of the interstitium and sarcoplasmic glycogen-rich processes with maturing oocytes. Synchronism in maturity among all of the oocytes in the ovary is shown at different stages of oogenesis. Such a pattern of oogenesis results in the production of many eggs at the same stage of development and is considered an adaptation for the dissemination of fertilized eggs that occurs only at the death of the gammarid host.

7

Fine structure of egg-forming complex ducts, eggshell formation and supporting neuronal plexus in progenetic Diplocotyle olrikii [Cestoda, Spathebothriidea]

88%

Poddubnaya L. G. , Mackiewicz J. S. , Swiderski Z. , Brunanska M. , Scholz T.

Acta Parasitologica

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2005

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tom 50

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nr 4

EN

Ultrastructural descriptions of the oviduct, fertilization canal, seminal receptacle, ovovitelline duct, vitelline reservoir, ootype, Mehlis' gland, proximal uterus, and neurosecretory elements associated with egg-forming ducts are given for the progenetic spathebothriidean tapeworm, Diplocotyle olrikii from the body cavity of Gammarus oceanicus. The functional significance of cortical granules of the oocyte, as necessary elements for joining vitelline material to an oocyte in the ovovitelline duct, is established. The proximal ootype has a vesicular epithelium and is the site of initial, nascent eggshell formation. Precursors of nascent eggshell are vesicles, synthesized in both the proximal ootype wall and vitelline cytoplasm that become associated with the newly formed shell. Major shell structure comes from subsequent deposition of shell globules from a disintegration of vitelline clusters. Mehlis' gland has a single secretory cell type. Secretory granules from Mehlis' gland become associated with the developing egg that passes through to the distal ootype and proximal uterus where egg-formation is completed. It is not known, however, whether Mehlis' gland secretion promotes breakdown of free vitelline cells, liberation of shell globules, confluence of shell globules on the developing eggshell or provides further structural components for the shell. Despite some differences in ootype morphology, the basic process of eggshell formation in D. olrikii may share much in common with the Pseudophyllidea and Caryophyllidea. Small vesicles and dense-core vesicles are in nerve terminals near duct musculature. Nerve terminals with large dense vesicles are described near, in, and within the seminal receptacle, fertilization canal and distal ootype. The possible physiological effects of exocrine neurosecretions are discussed.

8

Ultrastructure and cytochemistry of vitellogenesis in Wenyonia virilis Woodland, 1923 [Cestoda, Caryophyllidea]

75%

Swiderski Z. , Mlocicki D. , Mackiewicz J. S. , Miquel J. , Ibraheem M. H. , Brunanska M.

Acta Parasitologica

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2009

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tom 54

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nr 2

131-142

EN

Vitellogenesis in Wenyonia virilis was examined by transmission electron microscopy (TEM), including the cytochemical detection of glycogen at the ultrastructural level with the periodic acid-thiosemicarbazide-silver proteinate (PA-TSC-SP) technique. Mature vitelline follicles have cells in various stages of development, progressing from immature cells of gonial type near the periphery of the follicle to maturing and mature vitellocytes towards the centre. Maturation is characterized by: (1) increase in cell volume; (2) increase in nuclear surface area restoring the N/C (nucleo-cytoplasmic) ratio; (3) nucleolar transformation; (4) extensive development of parallel cisternae of GER, the shell-protein producing units; (5) development of Golgi complexes, engaged in shell-granule/shell-globule formation and packaging; (6) synthesis and storage of glycogen in the cytoplasm; (7) simultaneous, independent formation and storage of intranuclear glycogen; (8) continuous fusion of small shell-granules into larger shell-globules and fusion of these into large shell-globule clusters with a progressive increase in the number and size of the latter; and (9) disintegration of GER in the medial layer of vitellocyte cytoplasm, degenerative changes and accumulation of glycogen and shell-globule clusters within the cytoplasm. The functional significance of numerous shell-globule clusters and the relatively small amount of nuclear and cytoplasmic glycogen is analysed. Unlike vitellogenesis of other caryophyllids, the nuclear glycogen of mature vitellocytes in W. virilis is randomly dispersed in the nucleoplasm and never forms a high central accumulation, the so-called “nuclear vacuole”. The nutritive function of vitellocytes appears greatly reduced in W. virilis, a fact perhaps related to the intrauterine development of the early embryos. The ultrastructure of vitellogenesis in W. virilis is compared with that in other lower cestodes, both monozoic and polyzoic. Conclusions concerning interrelationships of the vitellogenesis pattern of the ultrastructural cytochemistry of mature vitellocytes of W. virilis to intrauterine embryonation, absence of uterine glands and an extensive uterus characteristic for this species, are drawn and discussed.