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PubMed1977

[Cytochemical characteristics of the labrocyte-like cells in the capsule of the plerocercoids of Triaenophorus nodulosus (Pallas, 1781) and Diphyllobothrium dendriticum (Nitzsch, 1824) cestodes].

Out of six fish species examined (Esox lucius, Paracottus kessleri, Perca fluviatilis, Leuciscus leuciscus baicalensis, Coregonus autumnalis migratorius, Thymallus arcticus baicalensis) labrocyte-like cells were detected in Esox lucius, Leuciscus leuciscus baicalensis, Coregonus autumnalis migratotius. The cells contain large metachromatic granules. Histochemical methods revealed in them sulfated and carboxylic acid mucopolysacharides. The amount of labrocyte-like cells in the capsules around plerocercoids of Triaenophrus nodulosis from Esox lucits liver depends on the age of the capsule and that of the plerocercoid. It increases when the connective tissue papsule is forming and decreases again under aging and degeneration of the capsule containing plerocercoid. The amount of labrocyte-like cells in the cestodes capsules of Raillietina increases sharply when they locate in an accidental organ (liver). This demonstrates the acuteness of organ reactivity to a nonspecific helminth.

Animals↗
PubMed1975

Studies on Spirometra theileri (Baer, 1925) n. comb. 2. Pathology of experimental plerocercoid infections.

The pathology associated with the early migratory phase of infection by the sparganum larvae of Spirometra theileri (Baer, 1925) Opuni and Muller, 1974 (Pseudophyllidea:Diphyllobothriidae), has been investigated in TO strain mice and in rhesus monkeys (Macaca mulatta). All infected mice developed haemorrhagic skin lesions and oedema of the joints and often ascites and peritonitis 3-6 weeks after infection. There was a 25% mortality in mice given plerocercoids orally, 37.5% in those injected with procercoids intraperitoneally. From eight weeks after infection larvae in both mice and monkeys were at various stages of encapsulation. One monkey which died three weeks after oral infection with 100 procercoids had developed ascites, haemorrhagic lesions and an acute peritonitis; infarcts were observed in the liver, lungs and spleen. In plerocercoid infections, scolices migrated directly through the duodenal wall within 45 minutes of oral infection in mice and 2 hours in monkeys, causing a minimum of damage apart from small haemorrhagic patches at the sites of penetration. In monkeys an eosinopoenia occurred 7 days after infection (a mean drop from 300 to 150 cells per cu mm), followed by a sudden rise (maximum of 1450 cells per cu mm) lasting from the 3rd to the 7th week. The histopathology and immunopathology associated with the various phases of infection were investigated in both mice and monkeys.

Animals↗
PubMedDate not supplied

[A study on the tegument and sensory receptors of the scolex of a tetraphyllidean cestode plerocercoid, by transmission and scanning electron microscopy (author's transl)].

The ultrastructure of bothridia and the myzorhynchus of a tetraphyllidean cestode plerocercoid is described. Two types of microtriches occur on the tegument of these organs. On the bothridium, the microtriches are lanceolated whereas on the mizorhynchus, they are filamentous. Uniciliated sensory receptors, which consist of a basal bulb contaning one or two electron-dense collars, are observed especially on the bothridia and myzorhynchus. A papilla is also described on the tegument. According to the present study, it is suggested that the rostellum of cyclophyllidean cestodes and the myzorhynchus of the tetraphyllideans are homologous. Moreover, the role in the attachment and sensory perception of the myzorhynchus is revealed.

Animals↗
PubMed1977

Localization of alkaline and acid phosphatase activity in the intestine of healthy breams (Abramis brama l.) and those infected with plerocercoid of tapeworm Ligula intestinalis (Linné 1758).

The examination included 40 breams 4 to 7 years old (18 infected and 22 uninfected). Alkaline and acid phosphatase activity, as shown by the azo-coupling method, has been localized in the oesophagus and the intestine, being the strongest in the epithelium. It was distinctly less intensive in the Lamina propria mucosae and in the intermuscular connective tissue of the oesophagus, in the submucosa, in the cells of AUERBACH plexus and in the blood vessel walls. Besides only the acid phosphatase activity was noted in single (sometimes rather numerous) spherical cells - visible within the epithelium and Lamina propria mucosae. The cells are known as the components of so called "yellow bodies" (melanine macrophage centers) entering particular numerously in the spleen and in the pronephric kidney of infected breams. The activity of both enzymes in the epithelium was considerably weaker in the last third of the intestine, and none in cloaca and in Tunica muscularis all over the length of the intestine (and oesophagus) except for some cells of the connective tissue separating the layers of muscle fibres. No perceptible differences in the activity and localization of both enzymes in the intestine were observed between infected and uninfected fishes examined in different seasons of the year.

Acid Phosphatase↗
PubMed1978

Comparison of the effects of the growth factor produced by Spirometra mansonoides and growth hormone in diabetic-hypophysectomized rats: lipid composition.

The effects of bovine growth hormone and the growth factor produced by plerocercoid larvae of the tapeworm, Spirometra mansonoides, on body growth and lipid composition in diabetic-hypophysectomized rats were compared. The diabetic-hypophysectomized control rats gradually lost weight throughout the experiment but both growth hormone and plerocercoids stimulated marked weight gains. Growth hormone treatment resulted in a loss of depot fat from the epididymal fat pads and caused a reduction of liver and serum cholesterol concentrations but had no effect on triglyceride concentrations of either liver or serum. However, plerocercoid infection resulted in increased weights of the epididymal fat pads and increased liver and serum triglyceride concentrations. Serum cholesterol was slightly increased but liver cholesterol was decreased in the plerocercoid-infected rats. Therefore, in the absence of pituitary hormones and insulin, these growth factors had similar effects on body growth but distinctly different effects on lipid metabolism.

Adipose Tissue↗
PubMed1978

Comparison of the effects of the growth factor produced by Spirometra mansonoides and growth hormone in diabetic-hypophysectomized rats: lymphoid tissue.

Growth and development of the thymus is dependent on secretions from the anterior pituitary, presumably growth hormone. Diabetes mellitus is known to reduce immunological competence. These studies compare the effects of bovine growth hormone (bGH) and the growth factor produced by plerocercoid larvae of the tapeworm, Spirometra mansonoides, on metabolism of lymphoid tissue, thymus and spleen, in hypophysectomized rats made diabetic with a single intraperitoneal injection of alloxan. Whereas the control diabetic-hypophysectomized rats gradually lost weight throughout the experimental period, both bGH and plerocercoid infection caused significant weight gains during the experimental period. The diabetic-hypophysectomized rats treated with bGH had significantly heavier thymuses and spleens than controls. Plerocercoid infection also caused significant increases in thymus weights. Both bGH and plerocercoids stimulated the metabolic activity of thymocytes isolated from treated rats and tested for their ability to incorporate 3H-thymidine into DNA in vitro. Thus, these growth factors have similar effects on the lymphoid tissue of diabetic-hypophysectomized rats which are apparently independent of normal insulin levels. Whether this anabolic effect is direct or mediated by somatomedin remains to be determined.

Animals↗
PubMed2026

"Not flying solo": phylogenetic identification and life-cycle insights of larval cestodes in the European flying squid Todarodes sagittatus (Cephalopoda: Ommastrephidae).

The European flying squid Todarodes sagittatus Lamarck is a widely distributed ommastrephid cephalopod in the Northeast Atlantic and Mediterranean Sea, yet its parasite fauna remains poorly documented in the Mediterranean Sea. In this study, two cestode larvae species infecting T. sagittatus from the Algerian coast (Western Mediterranean) were investigated using an integrative approach combining morphological observations and molecular analyses. A total of 63 squids were examined for parasitic infection. Cestodes in plerocercoid stage were detected in 31 individuals (prevalence of 46%), primarily located within the gastrointestinal tract, including the stomach, intestine, and caecum. Morphological features of the larvae were consistent with members of the order Phyllobothriidea but did not allow identification to the species level. Molecular analysis of the D1-D3 region of the 28S rDNA revealed two distinct larval lineages belonging to the genus Crossobothrium Linton, 1889. One lineage showed 100% sequence identity with the adult cestode Crossobothrium dohrnii (Oerley, 1885), a parasite of hexanchid sharks, confirming the identity of these larvae as plerocercoids of C. dohrnii. The second lineage clustered within the Crossobothrium clade but could not be assigned to a known species and is therefore referred to as Crossobothrium sp. The occurrence of these larvae in T. sagittatus, together with ecological data on squid diet and predator-prey relationships, suggests that this cephalopod acts as an intermediate or paratenic host in the life cycle of hexanchid cestodes. Infection likely occurs through predation on crustaceans acting as first intermediate hosts, while transmission to definitive hosts occurs when infected squids are consumed by sharks. These findings provide the first molecular identification of cestode larvae from T. sagittatus in the Mediterranean and highlight the important role of ommastrephid squids in the trophic transmission of elasmobranch parasites in pelagic ecosystems.

Crossobothrium↗
PubMed1979

[State of Spirometra "sparganum growth factor" research].

The plerocercoids of all Spirometra forms investigated up to now in this regard produce a "Sparganum Growth Factor" (SGF), i.e. one (or more) substance(s) with growth hormone-like effect on certain rodents. The SGF produced by the species S. mansonoides (SGF "mansonoides") is stronger effect than the SGF produced by all the other forms (SGF "non-mansonoides"). The physiological in its effects hitherto investigated mainly with SGT "mansonoides" in the USA are shortly mentioned. In order to get further insights the isolation, purification, and characterization of the SGF are necessary. The both kinds of SGF are also of taxonomic importance.

Animals↗