The fine structure of the intestine and hind gut of the larva of Trichinella spiralis

Abstract

The brush border of the intestinal cells of the infective larva of Trichinella spiralis is shown to consist of microvilli. It is suggested that large vesicular complexes in association with Golgi complexes may be responsible for the production of the mucopolysaccharide or mucoprotein filling the lumen of the intestine. Indirect evidence of a latent intranuclear virus infection is presented. The cuticle lining the hind gut, although continuous with the external cuticle, is not similar in structure.I would like to thank Dr D. L. Lee for instruction in all aspects of this work, Professor Boyd for the use of the Anatomy Department electron microscope and the Agricultural Research Council for financial support.

Histochemical and fine structure observations of the intestinal epithelium ofTrichuris suis (Nematoda: Trichuroidea)

“…7, 12, 15, 16). These represent dense, thickened areas of adjacent cell membranes and have been reg~rded as points of attachment in other nematode intestinal cells, e.g.A, lumbricoides (Sheffield, 1964); C. hepatica (Wright, 1963)and Trichinella spiralis (Bruce, 1966).…”

Studies on the movement, the cytology and the associated micro‐organisms of the intestine of Aspiculuris tetraptera (Nematoda)

“…The cells of the intestinal epithelium of Aspiculuris tetraptera are rather similar in their structure to those described for other nematodes (Kessel et aI., 1961;Wright, 1963;Sheffield, 1964;Jamuar, 1966;Bruce, 1966). The most important differences are the presence in A. tetraptera of a network of muscle fibres around the intestinal epithelium, the presence of membrane enclosed bodies which superficially resemble virus particles, and the attachment of micro-organisms to the apical surface of the cell.…”

“…The majority of nematodes have a simple, straight intestine consisting of a one-layered cellular epithelium. These cells bear on their apical (lumen) surface a bacillary layer which recent studies have shown to consist of microvilli (Kessel, Prestage, Sekhon, Smalley & Beams, 1961;Wright, 1963;Sheffield, 1964;Jamuar, 1966;Bruce, 1966). What is not generally realized is that while the basal (pseudocoel) surface of these intestinal cells is covered by a basal lamella in most nematodes (see Chitwood & Chitwood, 1950;Hyman, 1951), there are nematodes which also possess a network of muscle around part or all of the intestine but, according to Chitwood & Chitwood, these are unusual. In most nematodes movement of food along the intestine is brought about by the locomotory activity of the worm and the ingestion of more food which forces digesting food further along the intestine.…”

Can a chondrule precursor survive a shock wave?

“…The surface adhesion is due to van der Waals attraction, which is significantly weaker than the covalent bonding of Si-O. In fact, a small surface energy 0.014 J m −2 is observed (Heim et al 1999) for SiO 2 grains without sintering as compared to the theoretical value (0.58 J m −2 ) for the 110 plane of β cristobalite (Bruce 1966). A grain can roll around an adjacent grain, as shown experimentally (Heim et al 1999).…”