@article {724, title = {Ultrastructure of sperm development in the genus Ditylenchus (Nematoda: Anguinidae)}, journal = {NematologyNematology}, volume = {17}, year = {2015}, pages = {313-324}, author = {Slos, D. and Ensafi, P. and Claeys, M. and Yushin, V.V. and Decraemer, W. and Bert, W.} } @article {219, title = {Transovarial transmission of symbionts in Xiphinema brevicollum (Nematoda : Longidoridae)}, journal = {NematologyNematology}, volume = {2}, year = {2000}, note = {Coomans, A Vandekerckhove, TTM Claeys, MPart 4}, pages = {443-449}, abstract = {Transovarial transmission of bacterial symbionts in Xiphinema brevicollum was examined by means of electron microscopical- and fluorescence microscopical observations of intra-uterine and freshly laid non-embryonated eggs, as well as of embryonated eggs. The symbionts are mainly aggregated near one of the egg poles and this is observed in non-embryonated as well as in embryonated eggs. The bacteria are present in intestinal cells of first stage juveniles that are still enclosed by the egg-shell. In subsequent juvenile developmental stages their number increases and the intestinal cells are filled with the symbionts. Bacteria were not present in the genital primordium. It is hypothesised that the aggregated symbionts at one of the egg poles become enclosed in the E founder cell during embryogenesis and subsequently are distributed to the endodermal daughter cells. The bacteria become enclosed in the ovarial wall through an unknown mechanism only during the later stages of gonad development.}, isbn = {1388-5545}, author = {Coomans, A. and Vandekerckhove, T. T. M. and Claeys, M.} } @article {195, title = {Development and pharyngeal gland activities of Heterodera schachtii infecting Arabidopsis thaliana roots}, journal = {NematologyNematology}, volume = {4}, year = {2002}, note = {Tytgat, T De Meutter, J Vanholme, B Claeys, M Verreijdt, L Gheysen, G Coomans, APart 8}, pages = {899-908}, abstract = {As plant-nematode research continues to use the model host plant Arabidopsis thaliana more and more, we made a detailed life cycle study of Heterodera schachtii on this host, and investigated pharyngeal gland activities at the most crucial steps during the establishment of the parasitic interaction. In our experimental set up, in most cases induction of syncytia occurred during day 2, and the second moult during day 6. In pre-parasitic juveniles, both subventral glands contained numerous secretory granules, which gradually disappeared during intracellular migration of the juvenile through the roots. At the same time, both glands decreased in size and, after induction of the feeding cell, new kinds of secretory granules could be observed in the cytoplasm. During migration and induction of the feeding cell, the dorsal pharyngeal gland continuously increased in size. Secretory granules were already present in the dorsal gland of pre-parasitic juveniles, and a continuous synthesis of these granules was observed thereafter. Once the syncytium was induced, however, different types of secretory granules were formed.}, isbn = {1388-5545}, author = {Tytgat, T. and De Meutter, J. and Vanholme, B. and Claeys, M. and Verreijdt, L. and Gheysen, G. and Coomans, A.} } @article {171, title = {Cuticular structure of three Bunonema species and first description of the male of B. penardi Stefanski, 1914 (Nematoda : Bunonematidae)}, journal = {NematologyNematology}, volume = {6}, year = {2004}, note = {Times Cited: 0 Article English Borgonie, G State Univ Ghent, Dept Biol, Nematol Sect, KL Ledeganckstr 35, B-9000 Ghent, Belgium Cited References Count: 38 889AI BRILL ACADEMIC PUBLISHERS PLANTIJNSTRAAT 2, P O BOX 9000, 2300 PA LEIDEN, NETHERLANDS LEIDEN Part 4}, pages = {473-484}, abstract = {This study reanalyses some morphological and ultrastructural aspects of three Bunonema species. Specimens of B. penardi, B. hessi and B.franzi were studied using light microscopy and SEM. Bunonema franzi was also studied by TEM. The male of B. penardi is described, this being the first record of males in the genus Bunonema. Additional morphometric data on the females of this species are presented. SEM pictures show details of the deviant amphid position within the Bunonematidae. In contrast to earlier reports, our TEM results show that the evagination of the cuticle in ridges and tubercles is due to the thickening of the median zone of the cuticle. Ultrastructural details of the species-specific polygonal mesh network on the right body side are revealed. The rods that constitute this network lie above the epicuticle and are therefore extracuticular}, keywords = {BODY WALL, cuticle, FINE-STRUCTURE, GENUS, light microscopy, microscopy, morphology, Nematoda, PROTEIN, RHABDITIDA, SEM, STOMA, TEM, tubercle, ultrastructure, YOLK}, isbn = {1388-5545}, author = {Van Gansbeke, R. and Bert, W. and Govaerts, A. and Claeys, M. and Van Driessche, R. and Manhout, J. and Borgonie, G.} } @article {172, title = {Cuticular structure of three Bunonema species and first description of the male of B-penardi Stefanski, 1914 (Nematoda : Bunonematidae)}, journal = {NematologyNematology}, volume = {6}, year = {2004}, note = {Van Gansbeke, R Bert, W Govaerts, A Claeys, M Van Driessche, R Manhout, J Borgonie, GPart 4}, pages = {473-484}, abstract = {This study reanalyses some morphological and ultrastructural aspects of three Bunonema species. Specimens of B. penardi, B. hessi and B.franzi were studied using light microscopy and SEM. Bunonema franzi was also studied by TEM. The male of B. penardi is described, this being the first record of males in the genus Bunonema. Additional morphometric data on the females of this species are presented. SEM pictures show details of the deviant amphid position within the Bunonematidae. In contrast to earlier reports, our TEM results show that the evagination of the cuticle in ridges and tubercles is due to the thickening of the median zone of the cuticle. Ultrastructural details of the species-specific polygonal mesh network on the right body side are revealed. The rods that constitute this network lie above the epicuticle and are therefore extracuticular.}, isbn = {1388-5545}, author = {Van Gansbeke, R. and Bert, W. and Govaerts, A. and Claeys, M. and Van Driessche, R. and Manhout, J. and Borgonie, G.} } @article {178, title = {High-pressure freezing and freeze substitution of gravid Caenorhabditis elegans (Nematoda : Rhabditida) for transmission electron microscopy}, journal = {NematologyNematology}, volume = {6}, year = {2004}, note = {Claeys, M Vanhecke, D Couvreur, M Tytgat, T Coomans, A Borgonie, GPart 3}, pages = {319-327}, abstract = {Because chemical fixatives have a profound negative influence on tissue morphology and antigenicity, alternative fixation methods must be applied for some purposes. In this work we used high-pressure freezing (HPF) followed by freeze substitution to maximally preserve antigenicity and morphology. We developed a pipette method for bringing living Caenorhabditis elegans nematodes into the HPF recipient. Using cellulose tubes, it is possible to select individual nematodes for fixation. We were able to HPF complete adults and preserve the morphology in an enhanced fashion compared to chemically fixed tissue. Cellular organelles, especially mitochondria, were much better preserved. Uterine embryos protected by the intact eggshell were excellently preserved without the need for elaborate techniques. Antigenicity with MH27 and ICB4 antiscra was tested. With the MH27 serum, an adequate, reproducible, specific binding pattern with chemically fixed tissue could Only be achieved using purified antibodies, whereas with high-pressure freezing, unpurified MH27 antisera was effective. For ICB4 antisera, a reproducible specific binding pattern was achieved at a concentration of primary antiserum 1000x lower than that for chemically fixed tissue.}, isbn = {1388-5545}, author = {Claeys, M. and Vanhecke, D. and Couvreur, M. and Tytgat, T. and Coomans, A. and Borgonie, G.} } @article {186, title = {Lysosomal and pseudocoelom routing protects Caenorhabditis elegans from ricin toxicity}, journal = {NematologyNematology}, volume = {5}, year = {2003}, note = {Borgonie, G Link, CD Claeys, M Coomans, APart 3}, pages = {339-350}, abstract = {The resistance of the nematode Caenorhabditis elegans towards the highly potent toxin ricin has been studied. Incubation of C. elegans in ricin did not affect life span or progeny production. However, micro-injection of the ricin A-chain into the distal, syncitial gonad caused degeneration and sterility in test specimens, confirming that C. elegans ribosomes are sensitive. Using transmission electron microscopy, it was observed that ricin is effectively internalised into the intestinal cells. When pre-labelled with bold. the toxin reached only the lysosomes. When native toxin was used, the toxin was either routed to the lysosomes or underwent transcytosis to the pseudocoelomatic cavity and incorporation into embryos. None of the ricin reached either the trans Golgi network or the Golgi apparatus. considered essential for toxicity. The observed oral non-toxicity is therefore due to alternate sorting of the toxin. a mechanism not previously observed. The data indicate that, although ricin can opportunistically bind to, and be internalised by, cell surface receptors. these receptors are not sufficient to elicit toxicity.}, isbn = {1388-5545}, author = {Borgonie, G. and Link, C. D. and Claeys, M. and Coomans, A.} } @article {187, title = {Comparative morpho-anatomical studies of the female gonoduct within the Pratylenchidae (Nematoda : Tylenchina)}, journal = {NematologyNematology}, volume = {5}, year = {2003}, note = {Times Cited: 2 Article English Bert, W State Univ Ghent, Dept Biol, Ledeganckstr 35, B-9000 Ghent, Belgium Cited References Count: 33 712QZ BRILL ACADEMIC PUBLISHERS PLANTIJNSTRAAT 2, P O BOX 9000, 2300 PA LEIDEN, NETHERLANDS LEIDEN Part 2}, pages = {293-306}, abstract = {The cellular morphology of the gonoduct of six Pratylenchus species, three Pratylenchoides species, Radopholus similis, Zygorylenchus guevarai, Hirschmanniella loofi and Nacobbus aberrans was revealed by dissection and light microscopy. Except for Nacobbus aberrans, all studied species show an overall similarity in gonoduct construction, i.e., an ovary often ending with a ring of cells, an oviduct formed from two rows of four cells and a 12-celled spermatheca followed by a tricolumella containing 16-24 cells. Pratylenchoides magnicauda and Z guevarai did not diverge from the other Pratylenchidae in this respect, although their gonoduct differs from that of Amplimerlinius and Meloidogyne, both formerly postulated as related genera. The spermatheca structure observed in N. aberrans has not been reported elsewhere in the Nematoda, although the uterus is similar to that reported within the Heteroderinae and Meloidogyninae and the uterus comprises more than 300 cells, enlarging from a tricolumella to a polycolumella. Transmission electron microscopy of Z guevarai revealed details of the cytoplasmatic contact between epithelial cells and the germ cells; a finger-like ovarian wall cell extension was found penetrating the oocyte. The oviduct lacks a preformed lumen and comprises eight cells with highly plicated cell membranes. The spermatheca is constructed from flattened wall cells and is followed by columnar uterus cells where evidence of eggshell formation was demonstrated}, keywords = {CELLS, electron microscopy, ELECTRON-MICROSCOPY, GENUS, gonad, gonoduct, HETERODERINAE, Hirschmanniella, LESION NEMATODE, light microscopy, MELOIDOGYNE, microscopy, morphology, Nacobbus, Nematoda, PENETRANS NEMATA, Pratylenchoides, Pratylenchus, REPRODUCTIVE-SYSTEM, SPERMATHECA, TEM, ultrastructure, Zygotylenchus}, isbn = {1388-5545}, author = {Bert, W. and Van Gansbeke, R. and Claeys, M. and Geraert, E. and Borgonie, G.} }