Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CESTODE INFECTIONS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,027 records · Page 57Linked to original sources
PubMed2003

Spermiogenesis in the proteocephalidean cestode Proteocephalus torulosus (Batsch, 1786).

Spermiogenesis of the proteocephalidean cestode Proteocephalus torulosus (Batsch, 1786) was examined for the first time using transmission electron microscopy. Spermiogenesis begins with the formation of a distal cytoplasmic protrusion, a differentiation zone, at the periphery of the early spermatid. This differentiation zone is lined with cortical microtubules and contains two centrioles aligned along the same axis. Subsequently, each centriole is associated with the striated root and the intercentriolar body appears between them. A flagellar bud arises from each centriole, growing later as a free flagellum. Simultaneously, a median cytoplasmic process (MCP) develops distally to the flagella. The two flagella, which are of unequal length, become longer and rotate towards the MCP. At this stage, two arching membranes appear at the base of the differentiation zone. The nucleus elongates and when both flagella are fused with the MCP, the nucleus subsequently migrates into the MCP. Finally, the advanced spermatids detach from a condensing residual cytoplasm at the level of the arching membranes.

Animals↗
PubMed2003

Ultrastructure of spermiogenesis and the spermatozoon in the genus Joyeuxiella Fuhrmann, 1935 (Cestoda, Cyclophyllidea, Dipylidiidae): comparative analysis of J. echinorhynchoides (Sonsino, 1889) and J. pasqualei (Diamare, 1893).

This paper describes the ultrastructure of spermiogenesis and the mature spermatozoon of two Dipylidiidae cestodes, Joyeuxiella echinorhynchoides and J. pasqualei. In both species, spermiogenesis follows the type III described by Bâ and Marchand for the cyclophyllideans. Nevertheless, it is interesting to note the presence of striated roots associated with the centrioles. The spermatozoon presents the same ultrastructural features in J. echinorhynchoides and J. pasqualei. The apical cone in the anterior extremity of the sperm is more than 2.0 microm long in both J. echinorhynchoides and J. pasqualei. Both species present a single crest-like body, 150 nm thick in J. echinorhynchoides and 75 nm thick in J. pasqualei. The cortical microtubules are spiralled at an angle of 40-45 degrees to the spermatozoon axis in both Joyeuxiella species. A periaxonemal sheath and glycogen granules are also described in the mature sperm. We also describe, for the first time, the disposition of glycogen granules in two opposed and spiralled cords in cestodes and the formation of the periaxonemal sheath in the final stage of spermiogenesis.

Animals↗
PubMed2003

Reinvestigation of the spermatozoon ultrastructure of the cestode Proteocephalus longicollis (Zeder, 1800), a parasite of salmonid fish.

The reinvestigation of the fine structure of the mature spermatozoon of the proteocephalidean tapeworm Proteocephalus longicollis, a parasite of salmonid fish, has shown new characters not described previously for this species. They include a helicoidal crested body, 60-100 nm thick and localised at the anterior extremity of the spermatozoon. Also new is the finding that cortical microtubules in P. longicollis spermatozoon are of two types. The nucleus situated in the middle part of the gamete is rod-shaped anteriorly, but it is wound around one of the axonemes posteriorly. It is newly observed that both the anterior and posterior extremities of the spermatozoon of P. longicollis contain a single axoneme. The ultrastructural characteristics of the mature spermatozoon of P. longicollis coincide in their main features with those of the spermatozoon of P. torulosus, a parasite of cyprinid fish.

Animals↗
PubMed2004

Ultrastructural particularities of the spermatozoon of the cestode Electrotaenia malopteruri (Fritsch, 1886) (Proteocephalidae: Gangesiinae), a parasite of Malapterurus electricus (Siluriformes: Malapteruridae) from the river Nile, Egypt.

The fine structure of the mature spermatozoon of the tapeworm Electrotaenia malopteruri (Fritsch, 1886), a member of a supposedly primitive group of proteocephalidean tapeworms (Proteocephalidae: Gangesiinae), was studied by transmission electron microscopy for the first time. The mature spermatozoon of E. malopteruri is filiform, tapers at both extremities, and contains two axonemes of 9+"1" trepaxonematan type. A helicoidal crested body (60-150 nm thick) is present at the anterior extremity of the gamete. The twisting cortical microtubules (CM) line the periphery of the spermatozoon continuously. The nucleus, a fine cord of moderately condensed chromatin, occupies the middle part (region III) of the spermatozoon. The slightly electron-dense cytoplasm contains electron-dense granules in regions II and III and becomes more electron-dense at the end of region IV. The anterior and posterior extremities of the spermatozoon contain a single axoneme. Two modes of disorganisation of the axoneme at the posterior end of the mature spermatozoa are described for the first time in cestodes. The present data also indicate that the sperm ultrastructure of E. malapteruri shows some characters typical for onchobothriid tetraphyllideans, but it resembles that of Cyclophyllidea in the arrangement of twisting of the CM.

Animals↗
PubMed2004

The phylogeny of diphyllobothriid tapeworms (Cestoda: Pseudophyllidea) based on ITS-2 rDNA sequences.

Phylogenetic analysis of sequences of the ITS-2 rRNA genes of 20 samples of pseudophyllidean cestodes of the family Diphyllobothriidae (Ligula, Digramma, Diphyllobothrium, and Schistocephalus) from different hosts and geographical regions revealed that: (1) the inclusion of ligulids (previously family Ligulidae) to the Diphyllobothriidae is correct; (2) Schistocephalus appears as the most basal taxon of the Diphyllobothriidae, well separated from Ligula and Digramma, thus supporting the validity of Schistocephalinae Dubinina, 1962; (3) Digramma belonged with samples of Ligula, thus suggesting its invalidity as a genus; and (4) isolates of Ligula, presumably belonging to Ligula intestinalis, are paraphyletic, indicating that this species may represent a complex of separate taxa. Our results indicate the necessity for a taxonomic revision of the family Diphyllobothriidae.

Animals↗
PubMed2004

Characterization of development-related genes for the cestode Bothriocephalus acheilognathi.

Differential gene expression of mature and immature Bothriocephalus acheilognathi cestodes was analyzed using the suppression subtractive hybridization technique. Five mature-associated cDNAs were isolated and characterized. Virtual Northern blot and RT-PCR analyses confirmed that four of the five genes were upregulated in mature parasites. The sequence analysis revealed that one gene encoded the structural protein chorion precursor, and the three encoded functional proteins homologous to yolk ferritin, sodium/hydrogen exchanger and muscin-like protein. Another gene appeared to be specific to B. acheilognathi, encoding a putative metal-bound protein. Although results obtained in the present study are preliminary, the information about the five genes may provide clues for further investigation on the decline in parasite numbers during the maturation of B. acheilognathi.

Amino Acid Sequence↗
PubMed2004

Cadmium and lead concentrations in Gallegoides arfaai (Cestoda: Anoplocephalidae) and Apodemus sylvaticus (Rodentia: Muridae) from Spain.

Information on parasites of vertebrates living in terrestrial ecosystems as sentinels for heavy metal environmental pollution is scarce. The aim of the present study was to assess the concentration of cadmium and lead using the model Apodemus sylvaticus/Gallegoides arfaai in order to test the potential suitability of G. arfaai as a sentinel organism for lead and cadmium under natural field conditions. Samples of 15 A. sylvaticus as well as whole specimens of G. arfaai were analysed for both elements by inductively coupled plasma mass spectrometry. The level of cadmium in G. arfaai was always much lower than in the tissues of A. sylvaticus. Contrarily, values for lead in G. arfaai were found to be 6, 20 and 24-fold higher than in the kidney, liver and muscle of A. sylvaticus. We propose the model A. sylvaticus/G. arfaai as a promising bioindication system to evaluate environmental lead exposure in terrestrial habitats, especially for non-urban areas.

Animals↗
PubMed2004

Ultrastructural characters of the spermatozoon of the cestode Corallobothrium solidum Fritsch, 1886 (Cestoda: Proteocephalidea), a parasite of the electric catfish Malapterurus electricus.

The fine structure of the mature spermatozoon of the corallobothriine tapeworm Corallobothrium solidum Fritsch, 1886 (Cestoda: Proteocephalidea) from the electric catfish Malapterurus electricus from the Nile River in Egypt was studied by transmission electron microscopy for the first time. The filiform spermatozoon of C. solidum contains two axonemes of unequal length and a typical 9 + "1" trepaxonematan pattern. A single helicoidal crested body (30-200 nm thick) is localized at the anterior extremity of the gamete. The cortical microtubules line the periphery of the cell, largely parallel to the long axis of the spermatozoon and exhibiting signs of twisting at the beginning of region II. The nucleus, in the form of an electron-dense (largely in gametes of testes) and/or fibrous cord (largely in gametes from male reproductive ducts and seminal vesicle), coils in a spiral through the middle part (region III) of the spermatozoon. The cytoplasm contains electron-dense granules in regions II, III and partly in region IV. The cytoplasm of some spermatozoa exhibits an apparently higher electron-density at the end of the nucleated region (III), and continuously toward the middle part of region IV. The anterior and posterior extremities of the spermatozoa have a single axoneme. The ultrastructural features of the mature spermatozoon of C. solidum mostly coincide with those of the spermatozoon of other proteocephalideans, especially the gangesiine Electrotaenia malopteruri parasitizing the same host.

Animals↗
PubMed2005

Ultrastructure of the spermatozoon of Raillietina (Raillietina) baeri (Cyclophyllidea, Davaineidae) an intestinal parasite of the multimammate rat, Mastomys huberti (Rodentia, Muridae).

The mature Raillietina (Raillietina) baeri spermatozoon exhibits an apical cone of electron-dense material about 2.5 microm long and 0.5 microm wide and two helicoidal crest-like bodies roughly 100-125 nm thick. The latter are of different lengths, spiralized and stand in an angle of about 50 degrees with the spermatozoon axis. The axoneme is of the 9 + "1" pattern and does not reach the posterior extremity of the gamete. The nucleus is an electron-dense cord coiled in a spiral around the axoneme. The cytoplasm exhibits a posterior densification and contains few small electron-dense granules in regions I, II and V of the spermatozoon. In regions III and IV, it is divided into irregular compartments by walls of electron-dense material. The cortical microtubules are spiralized and make an angle of 40-50 degrees to the spermatozoon axis. In this work, we describe, for the first time, a spermatozoon of a davaineidaean cestode parasitic of mammals. This has enabled us to show a wide apical cone, which has never been described before in a cyclophyllidean species the spermatozoon of which has two crest-like bodies.

Animals↗
PubMed2005

Comparative study on the accumulation of heavy metals in different organs of tench (Tinca tinca L. 1758) and plerocercoids of its endoparasite Ligula intestinalis.

Concentrations of heavy metals (Cu, Fe, Zn, Mn, Cr, Pb and Cd) in some organs of tench and tissues of its parasite found in Kovada Lake (Turkey) were analyzed using atomic absorption spectrophotometry and subsequently compared with the data from sediments and water. Only Cu, Fe, Zn and Mn were detected in water, sediment, plerocercoids of Ligula intestinalis and fish samples, while levels of Cr, Pb and Cd were below the detection limits. Four elements were found at higher concentrations in the plerocercoid than in different fish tissues (muscle, liver and gill), being 1.6-37.4 times higher than that measured in muscle, liver and gill. Significant positive (for Cu) and negative (for Fe, Zn and Mn) correlations were found between the quantity of heavy metals in water and tissues of L. intestinalis plerocercoids while there were significant positive (for Cu and Zn) and negative (for Fe and Mn) correlations between the quantity of heavy metals in bottom sediment and tissues of L. intestinalis plerocercoids. Cestodes were found suitable to reflect the amount heavy metals in sediments, providing more reliable information about the actual pollution of the reservoirs.

Animals↗
PubMed2005

Effects of a combinations of emodepside and praziquantel on parasites of reptiles and rodents.

A new combination of two anthelmintic compounds containing emodepside and praziquantel (Profender, Bayer AG, Levekusen, Germany) was tested in pet rodents and reptiles. Topical application of the two compounds led to the quick disappearance of nematodes and cestodes from a broad spectrum of hosts including mice, jirds, snakes, anole lizards, turtles, monitor lizards, etc. In reptiles the dosage had to be increased, since the thick outer layer of the epidermis hinders the penetration of the compounds. In animals with an extremely thick epidermis (e.g. monitor lizards, leguans) the new product was applied under the armpits.

Administration, Topical↗
PubMed1996

Intraspecific variability of Proteocephalus exiguus La Rue, 1911 (Cestoda: Proteocephalidae) as studied by the random amplified polymorphic DNA method.

The intraspecific variability of Proteocephalus exiguus, a common fish cestode, was studied by the random amplified polymorphic DNA method. Isolates from four distant localities and four host species were investigated using eight arbitrary decamer oligonucleotides as primers. A relatively high variation of RAPD fingerprints from individual strobila was detected. The constant fragments observed in all isolates detected by eight primers characterized the species studied.

Animals↗
PubMed1999

A chromosome study of the tapeworm Bathybothrium rectangulum (Bloch, 1782) (Cestoda: Pseudophyllidea).

The diploid number 2n = 18 was revealed in Bathybothrium rectangulum, a specific parasite of barbels (Barbus spp.). All chromosome pairs were biarmed (pairs 1, 4, 7, 8, and 9 were metacentric; pairs 2, 3, and 6 were meta-submetacentric; and pair 5 was submetacentric) and small (from 1.49 to 2.95 microm). The C-banding method revealed pericentromeric heterochromatin in pairs 1, 3, 5, and 7; distinct C-bands in pairs 2, 4, 8, and 9; and a slight band in short arms of pairs 1 and 6. The karyotype of B. rectangulum is discussed with respect to the irresolute taxonomic position of B. rectangulum within the Pseudophyllidea.

Animals↗
PubMed2001

Spermiogenesis in the pseudophyllid cestode Eubothrium crassum (Bloch, 1779).

Spermiogenesis of the pseudophyllidean tapeworm Eubothrium crassum has been described by the aid of transmission electron microscopy for the first time. Initially, early spermatids form a distal cytoplasmic protrusion, a differentiation zone containing a small electron-dense, apically oriented region. Out of this region, two centrioles with rootlets develop. The centrioles become orientated in the same plane with the appearance of an intercentriolar body. Now, the long axes of the rootlets are parallel with each other and with the long axis of the nucleus. Two flagella of subsequently unequal length are formed very rapidly. Simultaneously, a median cytoplasmic process (MCP) develops distal to the flagella. Two arching membranes appear at the base of the differentiation zone. Each flagellum, still being in contact with an intercentriolar body, rotates to a position parallel with the MCP. The nucleus migrates very rapidly into the MCP at this stage. Subsequently, the two flagella fuse with the MCP. Finally, the basal bodies with the rootlets detach from the flagella, the intercentriolar body changes its structure and spermatids are pinched off from a condensing residual cytoplasm at the level of the arching membranes.

Animals↗
PubMed2005

Redescription of Houssayela sudobim (Woodland, 1935) (Cestoda: Proteocephalidea), a parasite of Pseudoplatystoma fasciatum (Pisces: Siluriformes) from the River Amazon.

The proteocephalidean cestode Houssayela sudobim (Woodland, 1935), the type and only species of Houssayela Rego, 1987, is redescribed on the basis of re-examination of its type-specimens and freshly collected material found in the intestine of the barred sudobim Pseudoplatystoma fasciatum (Siluriformes: Pimelodidae) from the River Amazon in Peru. The validity of the genus is confirmed, but its diagnosis is amended because suckers possess four pairs of cone-shaped (papilla-like) projections on their anterior margins (rather than 16, as reported in the original description), the actual number of testes is more than 400 in a proglottis (not 150 as given by Woodland, 1935) and the vitelline follicles form one dorsolateral medullary band and one lateral cortical band on both sides of proglottides. In addition, the distal (terminal) portion of the vagina has a double sphincter and the cirrus-sac has very thick walls; neither of these characteristics was mentioned in the original description. The specimen collected in Peru represents the first record of the species since its original description in 1935.

Animals↗
PubMed2005

Redescription of Cetorhinicola acanthocapax Beveridge & Campbell, 1988 (Cestoda: Trypanorhyncha) from the basking shark Cetorhinus maximus (Gunnerus).

Cetorhinicola acanthocapax Beveridge & Campbell, 1988 is redescribed based on adult specimens collected from a basking shark Cetorhinus maximus (Gunnerus) off the east coast of New Zealand. Both the mature and gravid segments are described for the first time, and the first scanning electron micrographs of the armature and scolex microtriches are provided. Novel features include the opening of the vagina anterior to the cirrus-sac and the extension of the vagina anterior to the cirrus-sac. Pectinate microtriches are present on the anterior quarter of the pars pedunculus scolecis scattered between filiform microtriches; the bothrial margins are covered with tridigitate microtriches, while the adherent surface of the bothria have pectinate microtriches. The additional morphological features described are consistent with a close association between Cetorhinicola Beveridge & Campbell, 1988 and the Eutetrarhynchoidea Guiart, 1927.

Animals↗
PubMed2005

Morphological characterisation of Andrya Railliet, 1893, Neandrya n. g. and Paranoplocephala Lühe, 1910 (Cestoda: Anoplocephalidae) in rodents and lagomorphs.

The taxonomic significance of the main morphological features of the 25 species allocated to Andrya Railliet, 1893 and Paranoplocephala Lühe, 1910 is re-evaluated in the light of the recent molecular phylogenetic hypotheses for anoplocephaline cestodes. The present analysis and the existing phylogenetic data suggest that the structure and complexity of the early uterus are not, as previously assumed, the main phylogenetic or systematic determinants for anoplocephaline cestodes. Instead, the position of the early uterus with respect to other organs, combined with the morphology of the female genitalia, appear to allow a fairly straightforward discrimination of the three genera recognised here, without contradicting current phylogenetic hypotheses. A new genus, Neandrya n. g., is proposed for N. cuniculi (Blanchard, 1891) n. comb. (previously in Andrya), amended diagnoses are provided for Andrya and Paranoplocephala and a diagnostic key to these three genera is presented.

Animals↗
PubMed2005

Aploparaksis kornyushini n. sp. (Cestoda: Hymenolepididae), a parasite of the woodcock Scolopax rusticola (L.), and its life-cycle.

Aploparaksis kornyushini n. sp. is described from a woodcock Scolopax rusticola L. from Lithuania, Russia (Tver' Region) and the Ukraine. Initially, one specimen of this tapeworm was described and figured by Kornyushin (1975) as A. scolopacis Yamaguti, 1935 together with another specimens belonging to the latter species. A. kornyushini n. sp. and A. scolopacis are morphologically very similar species. They can be distinguished by the slightly different length of the rostellar hooks and by the shape of the cirrus, which lacks basal bulbus in the new species. A. kornyushini can be readily distinguished from the remaining species of Aploparaksis Clerc, 1903 from woodcocks by the structure of its fully-developed embryophore, which has polar thickenings and two large or a few smaller lateral projection; this combination of characters is unknown for embryophores other Aploparaksis spp. (except for A. scolopacis). The life-cycle of A. kornyushini was studied under experimental conditions in Lithuania. The metacestodes were located under the chlorogogenous tissue of the intestine of Dendrobaena octaedra (Lumbricidae). The metacestode exhibits a pattern of postembryonal development typical for the cysticercoid modification termed an 'ovoid diplocyst'.

Animals↗