Electron microscopical study to assess thein vitroeffects of the synthetic trioxolane OZ78 against the liver fluke,Fasciola hepatica

Parasitology ◽  
2009 ◽  
Vol 136 (11) ◽  
pp. 1325-1337 ◽  
Author(s):  
L. HALFERTY ◽  
J. F. O'NEILL ◽  
G. P. BRENNAN ◽  
J. KEISER ◽  
I. FAIRWEATHER
Keyword(s):  
Endoplasmic Reticulum ◽  
Lipid Droplets ◽  
Fasciola Hepatica ◽  
Microscopical Study ◽  
Granular Endoplasmic Reticulum ◽  
Autophagic Vacuoles ◽  
Transmission Electron ◽  
Electron Microscopical ◽  
Tegumental Syncytium

SUMMARYAdultFasciola hepaticawere incubated for 48 hin vitroin the synthetic peroxide, OZ78 at a concentration of 100 μg/ml and then prepared for scanning and transmission electron microscopy. There was limited disruption to the external fluke surface, with only slight swelling and blebbing of the interspinal tegument in the midbody and ventral tail regions. By contrast, significant disruption was observed to the ultrastructure of the tegument and subtegumental tissues. There was severe swelling of the basal infolds in the tegumental syncytium and the flooding spread internally to affect the subtegumental tissues. In the tegumental system, there was swelling of the cisternae of granular endoplasmic reticulum and of the mitochondria, with the latter showing signs of breaking down. Autophagic vacuoles and lipid droplets were present and the synthesis of tegumental secretory bodies was much reduced. The gastrodermal cells were severely affected, with swelling and degeneration of the mitochondria and the presence of autophagic vacuoles and lipid droplets. The granular endoplasmic reticulum was swollen and vesiculated and the cells contained few secretory bodies. Both the vitelline and testis follicles showed evidence of extensive cellular disruption and degeneration. This study confirms previous data indicating the potential flukicidal activity of OZ78.

A transmission electron microscopical study of the tegument of Maritrema feliui (Digenea: Microphallidae)

2013 ◽  
Vol 58 (4) ◽  
Author(s):  
Zdzisław Świderski ◽  
Isabel Montoliu ◽  
Carlos Feliu ◽  
David Gibson ◽  
Jordi Miquel
Keyword(s):  
Surface Layer ◽  
Plasma Membrane ◽  
Outer Layer ◽  
Microscopical Study ◽  
The Other ◽  
Cytoplasmic Region ◽  
Transmission Electron ◽  
Basal Plasma Membrane ◽  
Basal Plasma ◽  
Electron Microscopical

AbstractThe tegument of the microphallid digenean Maritrema feliui, examined by means of TEM, is described as a syncytial epithelium organised into two layers. The outer layer is an external anucleate, cytoplasmic region connected to a second region composed of nucleate perikarya (cytons) deeply embedded in the surrounding cortical parenchyma. The surface layer of the tegument is covered by a plasma membrane with many deep invaginations, which are apparently pinocytotic. This layer also bears numerous large, electron-dense spines of two types, which are intracellular and attached to the basal plasma membrane. Its cytoplasm is rich in free ribosomes, contains numerous mitochondria, disc-shaped granules frequently arranged in a rouleau, and several large, moderately electron-dense, membranous bodies. The subtegumentary perikarya and their nuclei, which are both flattened, are described in detail, as are their connections with the surface tegument. These perikarya appear to be the source of the disc-shaped granules and some of the other inclusions present in the surface layer. The main characteristics of the tegumental structure of M. feliui are commented upon in relation to the findings of previous publications and their suggested functions.

scholarly journals FURTHER OBSERVATIONS ON THE FINE STRUCTURE OF THE PARIETAL EYE OF LIZARDS

1960 ◽  
Vol 8 (2) ◽  
pp. 483-499 ◽  
Author(s):  
Richard M. Eakin ◽  
Jane A. Westfall
Keyword(s):  
Lipid Droplets ◽  
Ganglion Cells ◽  
Nerve Fibers ◽  
Microscopical Study ◽  
Pigment Cells ◽  
Sceloporus Occidentalis ◽  
Neural Connections ◽  
System A ◽  
Electron Microscopical ◽  
Parietal Eye

An electron microscopical study of the third eye of the Western Fence Lizard, Sceloporus occidentalis, fixed with 1 per cent osmium tetroxide, pH 7.4–7.6, for 16 to 20 hours at 0°C., revealed the following new facts. The fibrillar system of the retinal photoreceptor consists of nine double fibrils enclosed in a sheath. Pigment cells and lens cells possess similar systems. Two short cylindrical centrioles are associated with the fibrillar apparatus: one, from which striated rootlets extend inward, lies at the base of the fibrils, with the other at an oblique angle to the axis of the system. A Golgi complex, whorls of endoplasmic reticulum, lipid (?) droplets, and other organelles and inclusions in the photoreceptors are described. An axon leads from the base of the photoreceptor into the nervous layer of the retina which consists of many nerve fibers and large ganglion cells. Although the pattern of neural connections has not yet been determined, some synapses were found. The parietal nerve consists of about 250 non-medullated fibers. The capsule of the eye usually has a layer of iridocytes, which contain rows of guanine (?) rods. A few parietal eyes of the Granite Night Lizard, Xantusia henshawi, were also examined. Large lipid (?) droplets occur in the bases of their receptoral processes.

Ultrastructural changes to the tegumental system and gastrodermal cells of adult Fasciola hepatica following treatment in vivo with a commercial preparation of myrrh (Mirazid)

2016 ◽  
Vol 91 (6) ◽  
pp. 672-685 ◽  
Author(s):  
M.M.O. Abdelaal ◽  
G.P. Brennan ◽  
A. Abdel-Aziz ◽  
I. Fairweather
Keyword(s):  
Fasciola Hepatica ◽  
Ultrastructural Changes ◽  
Muscle Fibres ◽  
Somatic Muscle ◽  
Secretory Body ◽  
Commercial Preparation ◽  
Transmission Electron ◽  
Body Production ◽  
Tegumental Syncytium

AbstractAn in vivo study in the laboratory rat model has been carried out to monitor changes to the tegument and gut of adult Fasciola hepatica following treatment with myrrh (‘Mirazid’). Rats infected with the triclabendazole-resistant Dutch isolate were dosed orally with Mirazid at a concentration of 250 mg/kg and flukes recovered 2, 3 and 7 days post-treatment (pt). The flukes were processed for examination by scanning and transmission electron microscopy. A variety of changes to the external surface were observed, culminating in the sloughing of the tegumental syncytium. Internal changes to the syncytium and tegumental cell bodies were more severe and were evident from 2 days pt onwards. Swelling of the basal infolds (leading to flooding of the surface layer) and a decline in secretory body production were the major changes seen. The gastrodermal cells were less severely affected than the tegument, pointing to a trans-tegumental route of uptake for Mirazid by the fluke. Some loss of muscle fibres in the main somatic muscle layers was observed, which may be correlated with the decline in movement of flukes seen at recovery.

Fasciola hepatica: surface and internal tegumental changes induced by treatment in vitro with the sulphoxide metabolite of albendazole (‘Valbazen’)

Parasitology ◽  
2003 ◽  
Vol 126 (2) ◽  
pp. 141-153 ◽  
Author(s):  
J. F. BUCHANAN ◽  
I. FAIRWEATHER ◽  
G. P. BRENNAN ◽  
A. TRUDGETT ◽  
E. M. HOEY
Keyword(s):  
Electron Microscopy ◽  
Fasciola Hepatica ◽  
Benzimidazole Derivative ◽  
Microtubule Inhibitors ◽  
Transmission Electron ◽  
Basal Plasma ◽  
Benzimidazole Anthelmintic ◽  
Distinct Increase ◽  
Surface Changes

A morphological study has been carried out to determine the effect of the active sulphoxide metabolite of the benzimidazole anthelmintic, albendazole (ABZ-SO) on the adult liver fluke, Fasciola hepatica. Whole flukes were treated with ABZ-SO for 12 and 24 h at a concentration of 10 μg/ml. The changes in response to drug treatment were examined by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and tubulin immunocytochemistry (ICC). No surface changes were apparent following 12 h ABZ-SO treatment, but localized blebbing was observed after 24 h, which became more extensive towards the posterior region of both surfaces. TEM of sections from the posterior midbody region revealed that ABZ-SO caused the accumulation of secretory bodies in the tegumental cells and in their cytoplasmic connections and, after 24 h, just above the basal plasma membrane. Localized blebbing of the apical membrane also occurred. The morphology of the Golgi complexes within the tegumental cells began to change after 12 h treatment with ABZ-SO and, by 24 h, few complexes were observed. A distinct increase in tubulin immunoreactivity occurred after 12 h treatment, but this decreased after 24 h. The results obtained are consistent with those expected for microtubule inhibition. They are discussed in relation to the action of established microtubule inhibitors, as well as the benzimidazole derivative, triclabendazole.

An Electron Microscopical Study of Neutral Red Granules in Mouse Exocrine Pancreas

1964 ◽  
Vol s3-105 (70) ◽  
pp. 219-226
Author(s):  
JENNIFER M. BYRNE
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Golgi Apparatus ◽  
Normal Tissue ◽  
Exocrine Pancreas ◽  
Ultrastructural Level ◽  
Neutral Red ◽  
Microscopical Study ◽  
Zymogen Granules ◽  
Electron Microscopical

The neutral red granule cycle in the mouse exocrine pancreas was studied with the electron microscope in order to discover what changes appear at an ultrastructural level in cells treated with neutral red. There are no changes in the endoplasmic reticulum, the nucleus, the Golgi apparatus, the zymogen granules, or the mitochondria of stained cells when compared with normal tissue. Osmiophil inclusions are found which in their size and distribution correspond to the neutral red granules seen under the light microscope. Such inclusions are not seen in normal tissue. They resemble morphologically the lysosomes of various tissues.

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