THE MORPHOLOGY, HISTOLOGY, AND FINE STRUCTURE OF THE ADULT STAGE OF THE CYCLOPHYLLIDEAN TAPEWORM Hymenolepis diminuta

Lumsden, Richard D.; Specian, Robert D.

doi:10.1016/b978-0-12-058980-7.50008-7

Cited by 79 publications

(50 citation statements)

References 103 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The protonephridial system of T. parva larvae resembles, to a great extent, that described from adult (OEwiderski et al 1973, Lumsden and Specian 1980, Lumsden and Hildreth 1983 and larval cestodes (Xylander 1987(Xylander , 1992OEwiderski et al 2002a;OEwiderski and Mackiewicz 2004). Circularly-arranged, minute pores or "nephrostomes", as described from three species of cyclophyllideans (OEwiderski et al 1973), are between the endings of the outer row of digitiform processes arising from the nephridial funnel and the surface of the leading edge of the flame cell.…”

Section: Protonephridial Systemmentioning

confidence: 79%

“…The cytoplasmic projections with characteristic large, electron-dense, spherical granules (type-1) observed between scolex muscles and, in particular, within the sucker musculature of T. parva (see Figs 12,[14][15][16][17][18][19] resemble those described in the proximity of the acetabular myocytons of Hymenolepis diminuta (Rudolphi, 1819) (see Specian et al 1979, Lumsden andSpecian 1980); they were believed to originate from the multipolar cells filled with the same type of electron-opaque secretory granules found in perinuclear regions. Initially, these cells were interpreted as unicellular endocrine glands (Specian et al 1979), probably because of their epithelial origin; however, at the ultrastructural level, these glands were considered as exhibiting many "non-neural" characteristics.…”

Section: Functional Correlates: Possible Role Of Regulatory Peptides mentioning

confidence: 83%

“…Initially, these cells were interpreted as unicellular endocrine glands (Specian et al 1979), probably because of their epithelial origin; however, at the ultrastructural level, these glands were considered as exhibiting many "non-neural" characteristics. According to Specian et al (1979) and Lumsden and Specian (1980), the activity of these cells was of a neuroendocrinetype that had the possibility of establishing a direct communication with the adjacent muscular tissue via a gap junction. The secreted material might function as a long-acting modulator of acetabular muscle activity (Specian et al 1979).…”

Section: Functional Correlates: Possible Role Of Regulatory Peptides mentioning

confidence: 99%

See 2 more Smart Citations

Post-embryonic development and ultrastructural characteristics of the polycephalic larva of Taenia parva Baer, 1926 (Cyclophyllidea, Taeniidae)

Z¹,

Miquel²,

Młocicki³

et al. 2007

Acta Parasitologica

View full text Add to dashboard Cite

Post-embryonic development and fully-formed polycephalic larvae of Taenia parva Baer, 1926 were examined by light (LM) and transmission electron microscopy (TEM). Three developmental stages were recognised: (1) an early stage of exogenous budding at the surface of the central vesicle; (2) a stage of polycephalic cyst development accompanied by segmentation of the growing larval strobile and an obvious decrease in the size of the central vesicle; (3) fully-formed larval strobile and invaginated scoleces. In fully-developed encysted polycephalic larvae, there are usually 14-24 segmented larval strobilae, each terminating with an invaginated scolex; larval strobilae arise from a common central vesicle and remain attached posterior to it during the entire development. The number of segments varies between 109 and 120 per larval strobila. The polycephalic larvae examined closely resemble the strobilocercus type of taeniid larvae. The structure of developing and fully-formed larvae was examined by TEM. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles and medullary parenchyma of larvae exhibit general similarity with the same structures in adults at both LM and TEM levels. The morphogenesis of the larva of T. parva is compared with that of the polycephalic larvae of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually-multiplying cestode larvae (mesocestoidids, hymenolepidids and dilepidids).

show abstract

Section: Protonephridial Systemmentioning

confidence: 79%

Section: Functional Correlates: Possible Role Of Regulatory Peptides mentioning

confidence: 83%

Section: Functional Correlates: Possible Role Of Regulatory Peptides mentioning

confidence: 99%

See 1 more Smart Citation

Post-embryonic development and ultrastructural characteristics of the polycephalic larva of Taenia parva Baer, 1926 (Cyclophyllidea, Taeniidae)

Z¹,

Miquel²,

Młocicki³

et al. 2007

Acta Parasitologica

View full text Add to dashboard Cite

show abstract

“…There is immense variety, however, in the form and arrangements of these structures: they appear as bullet-shaped projections in neat arrays in the adult Transversotrema patialense or as serrated spines in Microphallus (5). The evolutionary relations of these structures are also intriguing: it is an interesting fact that another major group of parasitic flatworms, the tapeworms (cestodes), are covered with very small, slender, flexible microvilli (microtriches) that also consist of hexagonally packed actin filaments (6). Many of the attachment or ornamental spines or hooks so characteristic of parasites of widely different species (e.g.…”

mentioning

confidence: 99%

Schistosome surface spines are "crystals" of actin.

Cohen¹,

Reinhardt²,

Castellani³

et al. 1982

The Journal of Cell Biology

View full text Add to dashboard Cite

T h e c h a r a c t e r i s t i c s p i n e s o n t h e s u r f a c e o f t h e s c h i s t o s o m e f l a t w o r m t e g u m e n t c o n s i s t o f h e x a g o n a l l y p a c k e d a c t i n f i l a m e n t s . E l e c t r o n m i c r o s c o p y o f i s o l a t e d s p i n e s s h o w s t h a t t h e i r s t r u c t u r e is v e r y s i m i l a r t o t h a t o f o t h e r b u n d l e s o f a c t i n c r o s s -l i n k e d w i t h an a d d i t i o n a l p r o t e i n .One of the most severe and widespread of human diseases is caused by the parasitic schistosome flatworm. The life cycle of this blood fluke involves asexual larval reproduction in an intermediate snail host, giving rise to the infectious free-swimming cercarial form. After penetrating the human tissue, the worms develop into adults that become situated in the gut or bladder veins; the female generally lodges--in permanent copulation-in the ventral groove of the male worm. The surface of the male is studded with prominent rigid intracellular spines that may be critical in attachment.Our attention was drawn to these structures by the report that they consist of a "crystalline protein" (sic) (l). The size of the male worm (1-1.5 cm long and 1-mm thick) and the size of the spines (-2.5-3 #m in length) make it feasible to examine these structures by negative staining in the electron microscope. Scraping the surface with a sharp blade readily produces spines--often, however, in low yield. When negatively stained with uranyl acetate, these structures are seen to be comprised ofactin filaments aligned in register axially and spaced laterally in a regular array. The axial period is 385 A, and is divided into three bands (Fig. I a, c). This image is, in fact, very similar to that given by other actin bundles in a variety of systems. [1,0] view, the axial repeat shows two weak stain-excluding stripes due to protein cross-bridges between actin filaments, and one bright node (where the bridge is obscured by a filament lying directly over it). In the [1,1] view, three equivalent stripes are seen in each axial repeat (see reference 3 for details). The projected lateral repeat in the spine ( a ) is ~100 ,g, corresponding to a spacing between filaments of 100(2/~/3) = 116 g,. Insert in a shows the optical diffraction pattern of the lower portion of the spine in a. The pattern shows off meridional reflections on the 1st, 6th, and 7th layer lines characteristic of the actin helix. An additional meridional reflection is present on the 3rd layer line due to the crossbridges. Note that additional actin layer lines (generally not seen) are present. They are due to the contribution of the cross-bridges. Other weak reflections midway between layer lines indicate a longer true repeat of the structure. The actin bundles in the spines could be preserved by freezing the worms in liquid nitrogen in a mixture of 50% glycerol, 50% actin buffer (5 mM NaPO4, pH 7.4, 50 mM NaCl, 0.5 mM ATP.Na2, 0.5 mM CaCI2, 3 mM NAN3). Specimens negatively stained with 1% uranyl ace...

show abstract

“…The presence of internal leptotriches which extend from the flame cell cytoplasm into the lumen around the flame cells does not exist in trematodes which possess external leptotriches (McCullough and Fairweather, 1991). The present external leptotriches in N. kashmirensis have been demonstrated in another cestodes, as in the amphilinid, Austramphilina elongate (Rohde and Georgi, 1983); the cyclophyllidean ,Hymenolepis diminuta (Lumsden and Specian, 1980); and the tetraphyllidea, Trilocularia acanthiaevulgaris (McCullough and Fairweather,1991).…”

Section: Discussionmentioning

confidence: 89%

Ultrastructural studies of the tegument and excretory system of the cestode Nematotaenia kashmirensis (Fotedar, 1966) infecting the toad Bufo regularis in Egypt.

Kabbany

2009

Egypt. J. of Aquatic Biolo. and Fish.

View full text Add to dashboard Cite

THE MORPHOLOGY, HISTOLOGY, AND FINE STRUCTURE OF THE ADULT STAGE OF THE CYCLOPHYLLIDEAN TAPEWORM Hymenolepis diminuta

Cited by 79 publications

References 103 publications

Post-embryonic development and ultrastructural characteristics of the polycephalic larva of Taenia parva Baer, 1926 (Cyclophyllidea, Taeniidae)

Post-embryonic development and ultrastructural characteristics of the polycephalic larva of Taenia parva Baer, 1926 (Cyclophyllidea, Taeniidae)

Schistosome surface spines are "crystals" of actin.

Ultrastructural studies of the tegument and excretory system of the cestode Nematotaenia kashmirensis (Fotedar, 1966) infecting the toad Bufo regularis in Egypt.

Contact Info

Product

Resources

About