The Attachment and Penetration Apparatus of the Miracidium of Schistosoma

1971 ◽  
Vol 45 (2-3) ◽  
pp. 229-235 ◽  
Author(s):  
G. K. Kinoti
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Body Surface ◽  
Leucine Aminopeptidase ◽  
The Body ◽  
Intermediate Hosts ◽  
Free Swimming ◽  
History Of ◽  
Apical Papilla ◽  
Attachment Organ

Preliminary electron microscope observations have shown that in the miracidium of Schistosoma mattheei the surface of the apical epidermal plate consists of branching and anastomosing microvilli. It is suggested that this arboreal arrangement serves to attach the miracidium to the body surface of snail hosts during attempts to penetrate; the apical papilla can therefore be regarded as an attachment organ, functionally analogous to the suckers of the adult schistosome. It is also suggested that the degree of ‘fit’ between the attachment organ and the snail body surface may be an important factor determining the success of attempts by the miracidium to penetrate.Electron microscopy has also shown that the so-called penetration and apical glands are single flask-shaped cells. No endoplasmic reticulum and very few ribosomes were seen in these cells and it is therefore suggested that, in the mature (free-swimming) miracidium, the “glands” are not functional as such; they are simply sacs full of fluid. If they contain histolytic substances they must either have been synthesized at an earlier stage in the life history of the organism or they are synthesized elsewhere and passed into the “glands”.Histochemical attempts to identify leucine aminopeptidase and mucin in the contents of the “glands” of S. mansoni miracidia were unsuccessful. It is concluded that these substances probably do not play any role in the penetration into or attachment on snail intermediate hosts by S. mansoni miracidia.

The life history of the rat lung-worm, Angiostrongylus cantonensis (Chen) (Nematoda: Metastrongylidae).

1955 ◽  
Vol 3 (1) ◽  
pp. 1 ◽  
Author(s):  
MJ Mackerras ◽  
DF Sandars
Keyword(s):  
Pulmonary Arteries ◽  
Blood Stream ◽  
The Body ◽  
Angiostrongylus Cantonensis ◽  
Intermediate Hosts ◽  
Anterior Portion ◽  
Third Stage ◽  
History Of ◽  
The Central Nervous System ◽  
The Right

Adult Angiostrongylus cantonensis live in the pulmonary arteries. Unsegmented ova are discharged into the blood stream, and lodge as emboli in the smaller vessels. First-stage larvae break through into the respiratory tract, migrate up the trachea, and eventually pass out of the body in the faeces. Slugs (Agriolimax laevis) act as intermediate hosts. Two moults occur in the slug, and third-stage larvae appear about the 17th day. The larvae remain within the two cast skins until freed in the stomach of the rat by digestion. They then pass quickly along the small intestine as far as the lower ileum, where they leave the gut and become blood-borne. They congregate in the central nervous system, and have been found there 17 hr after ingestion. The anterior portion of the cerebrum is the most favoured site, and here the third moult takes place on the sixth or seventh day and the final one between the 11th and 13th days. Young adults emerge on the surface of the brain from the 12th to 14th day, and spend the next 2 weeks in the subarachnoid space. From the 28th to 31st days they migrate to the lungs via the venous system, passing through the right side of the heart to their definitive site in the pulmonary arteries. The prepatent period in the rat usually lies between 42 and 45 days.

Echinostoma revolution (Froelich, 1802) Looss, 1899 and Isthmiophora melis (Schrank, 1788) Lühe, 1909 (Echinostomatinae, Digenea): Scanning electron microscopy of the tegumental surfaces

1984 ◽  
Vol 58 (3) ◽  
pp. 187-195 ◽  
Author(s):  
Lesley R. Smales ◽  
Harvey D. Blankespoor
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Topography ◽  
Body Surface ◽  
Secretory Granules ◽  
The Body ◽  
Taxonomic Character ◽  
Secretory Structures ◽  
Unusual Structure ◽  
Scanning Electron

ABSTRACTA detailed study of the surface topography of the echinostomes Echinostoma revolution and Isthmiophora melis has been carried out using SEM. The tegument of the body surface has a cobblestone-like appearance with interspersed pits. The presence of possible secretory granules is noted. Observations of the anterior end reveal that the collar spines are retractable. An unusual structure is described from the ventral gap of the spiny collar of E. revolutum. The origins of this structure and the possible functions of the spiny collar are discussed. The shape and distribution of body spines is described. Differences in cirrus morphology for the two species are described. The taxonomic position of, I. melis and the significance of cirrus morphology as a useful taxonomic character are discussed. Four types of presumed sensory or secretory structures occur—ciliated, domed, button and bilobed papillae. Their distribution is described and possible functions discussed.

scholarly journals Using of the method of electron microscopy for the identification and analysis of clinically implicit pathogenetic manifestations

2018 ◽  
Vol 7 (3) ◽  
pp. 113-116
Author(s):  
L. G. Nikonova ◽  
V. V. Banin ◽  
I. G. Stel'nikova
Keyword(s):  
Diabetes Mellitus ◽  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
B Cells ◽  
Secretory Granules ◽  
Electron Microscopic Examination ◽  
The Body ◽  
Electron Microscopic ◽  
Latent Form ◽  
Insulin Cells

Electron microscopic examination of B cells of pancreatic islets of the pancreas in dogs with normal (n=10) and impaired glucose tolerance (n=10) was performed. Ultrastructural features of the organization of insulin cells associated with an increased requirement of the hormone in the body with the latent form of diabetes mellitus are established. In B cells, signs of functional tension due to unregulated secretion, manifested by the expansion of endoplasmic reticulum cisterns, Golgi complex hypertrophy, an increase in the number of immature secretory granules and vacuoles in the cytoplasm are revealed in B cells.

scholarly journals Insecticidal effect of diatomaceous earth and dolomite powder against Corn weevil Sitophiluszeamais Motschulsky, 1855 (Coleoptera: Curculionidae)

2020 ◽  
Vol 44 (6) ◽  
pp. 490-497
Author(s):  
Alyssa Cristina Oliveira FREITAS ◽  
Adriana Aparecida Sinopólis GIGLIOLLI ◽  
Ronaldo Roberto Tait CALEFFE ◽  
Helio CONTE
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Body Surface ◽  
Diatomaceous Earth ◽  
The Body ◽  
Insecticidal Effect ◽  
Laboratory Conditions ◽  
Inert Dusts ◽  
Stored Grains ◽  
Scanning Electron

Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) which develops inside the grain, is an aggressive pest of stored grains. Here, we evaluated the efficiency of diatomaceous earth (DE), Diatomita CI/325 CX, and dolomite (DOL), Dolomita Dr. Kanyo, against S. zeamais reared on corn under laboratory conditions and observed external alterations on treated insects using scanning electron microscopy (SEM). Insects treated with both DE and DOL were impregnated with particles on the body surface, and they showed 100% mortality after 10 days of exposure. Damages caused by inert dusts may have contributed to dehydration and desiccation, consequently, leading insects to death. Thus, diatomaceous and dolomite were effective against S. zeamais under laboratory conditions.

scholarly journals An unusually elongate endogeic centipede from Sardinia (Chilopoda: Geophilidae)

2016 ◽  
Author(s):  
Lucio Bonato ◽  
Marzio Zapparoli ◽  
Leandro Drago ◽  
Alessandro Minelli
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
Body Surface ◽  
Sensu Stricto ◽  
The Body ◽  
European Species ◽  
Scanning Electron ◽  
Trunk Segments

Endogeophilus ichnusae gen. et sp. nov. (Chilopoda: Geophilidae sensu stricto) is described based on three specimens from two localities in south-western Sardinia, examined by light and scanning electron microscopy. The new centipede resembles the rare Ibero-Pyrenean genus Galliophilus Ribaut & Brolemann, 1927 in some features, especially in the forcipular segment, and the temperate European species Geophilus electricus (Linnaeus, 1758) in other features, especially in the ultimate leg-bearing segment. However, the true affinities of E. ichnusae gen. et sp. nov. are uncertain, because the new species departs significantly from the majority of geophilids for the higher number of legs (91–107 pairs in the specimens examined), the slender trunk segments (the sternites being longer than wide), the relatively stout legs (the tarsus being only about twice as long as wide) and the very short setae (≤ 15 mm) scattered on the body surface. All these features are probably derived and suggest adaptation to a more strictly endogeic habit than other geophilids.

Electron Microscopy of the Hypertrophic Scar

1971 ◽  
Vol 29 ◽  
pp. 302-303
Author(s):  
C. W. Kischer ◽  
H. Linares ◽  
M. Dobrkowsky ◽  
D. L. Larson
Keyword(s):  
Electron Microscopy ◽  
Body Surface ◽  
Hypertrophic Scar ◽  
Normal Skin ◽  
The Body ◽  
Skin Area ◽  
Hypertrophic Scarring ◽  
Loss Of Function ◽  
Reticular Dermis ◽  
Severe Loss

Hypertrophic scarring frequently occurs during or after the healing of deep second degree or third degree burns or equivalent trauma to the body surface. Clinically, the scar begins as a generalized firming or hardening of the skin area with an increased reddening over that of normal skin. These conditions intensify rapidly. The scar elevates and begins contracting, sometimes resulting in serious deformities, grotesque appearance, and severe loss of function.During development of the scar the reticular dermis undergoes an unusual reconstruction. The collagen fibers first become oriented into whorl-like arrangements, which most likely develop further into discrete nodules. The etiology of the hypertrophic scar is unknown. However, since nodular formation is so characteristic for the scar an examination of the nodule itself may suggest etiologic possibilities for the scar.

scholarly journals Some ultrastructural superficial changes in house fly (Diptera: Muscidae) and blow fly (Diptera: Calliphoridae) larvae induced by eucalyptol oil

2004 ◽  
Vol 46 (5) ◽  
pp. 263-267 ◽  
Author(s):  
Kabkaew L. Sukontason ◽  
Kom Sukontason ◽  
Noppawan Boonchu ◽  
Somsak Piangjai
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Musca Domestica ◽  
Body Surface ◽  
House Fly ◽  
The Body ◽  
Blow Fly ◽  
Chrysomya Megacephala ◽  
Bleb Formation ◽  
Scanning Electron

The ultrastructural superficial changes in third instar house fly (Musca domestica) and blow fly (Chrysomya megacephala) induced by eucalyptol oil were observed using scanning electron microscopy. Dipped in 0.902 g/ml eucalyptol for 30 sec, the larvae integument of both species showed significant aberrant appearance of the body surface, particularly swelling integument, bleb formation, partial breach and deformation of spines.

Life history of the nematode Rhabdochona hellichi, a parasite of the barbel in the Jihlava River, Czech Republic

1995 ◽  
Vol 69 (1) ◽  
pp. 59-64 ◽  
Author(s):  
F. Moravec ◽  
T. Scholz
Keyword(s):  
Czech Republic ◽  
The Body ◽  
Seasonal Cycles ◽  
Intermediate Hosts ◽  
Danube Basin ◽  
Mean Intensity ◽  
Barbus Barbus ◽  
History Of ◽  
Caddis Fly ◽  
Very High

AbstractFrom April 1992 until June 1993, the seasonal dynamics of Rhabdochona hellichi (Šrámek 1901) in its definitive host, the barbel (Barbus barbus), was studied in the Jihlava River (the Danube basin), Czech Republic. The parasite occurred in barbel throughout the year (overall prevalence 93% and intensity of infection 1–1384 [mean 78] nematodes per fish), but there were distinct seasonal fluctuations in prevalence and mean intensity values associated with the parasite's seasonal cycle of maturation. Prevalence was very high (usually 100%) during most months of the year, while lowest values were recorded in August and October. The highest values of mean intensity occurred in April. Both prevalence and mean intensity values increased with the body length of the hosts. The parasite exhibited a distinct annual cycle of maturation with egg-producing females present only fmm June until August, whereas larvae occurred in barbel mostly from September until April of the next year. Trichopteran (caddis-fly) larvae of the genus Hydropsyche (H. angustipennis and H. pellucidula) were found as natural intermediate hosts of R. hellichi (prevalence 4%, intensity 1–10 nematode larvae). The strictly seasonal maturation of this nematode may be associated with the temperature regime in the locality and seasonal cycles of maturation of its intermediate hosts.

Fasciola hepatica: surfaces involved in movement of miracidia and cercariae

2001 ◽  
Vol 75 (1) ◽  
pp. 1-5 ◽  
Author(s):  
C.E. Bennett
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Fasciola Hepatica ◽  
Time Lapse ◽  
Ventral Surface ◽  
The Body ◽  
Power Stroke ◽  
Free Swimming ◽  
Lateral Plane ◽  
Scanning Electron

Rapid freezing and substitution with fixative prior to scanning electron microscopy was used to demonstrate the pattern of beat and recovery of the cilia of free swimming miracidia ofFasciola hepatica. There were stages of dexioplectic metachronal co-ordination and the power stroke was approximately 15° anticlockwise from the anterior–posterior axis. Around the circumference of the body of the miracidia there were approximately 12 metachronal waves of power and recovery. Free-swimming cercariae were recorded by time-lapse photography and, after conventional fixation, by scanning electron microscopy. Cercarial tail-beats were to the posterior of the body in the lateral plane at a rate of 8 Hz. The tail has paired lateral ridges positioned to act as leading edges. There is an array of 32 sensory papillae on the mid-ventral surface of the tail. The tegument of the most distal part of the tail is described: it is free of sensory endings and the surface shows a spiral pattern.

Electron microscopic study of cuticular and cellular structures of the body surface of the winter stonefly nymph, Taeniopteryx burksi Ricker and Ross (Plecoptera: Taeniopterygidae)

1985 ◽  
Vol 63 (6) ◽  
pp. 1360-1367 ◽  
Author(s):  
N. N. Kapoor
Keyword(s):  
Electron Microscopy ◽  
Body Surface ◽  
Gland Cell ◽  
Epidermal Cells ◽  
The Body ◽  
Cellular Structures ◽  
Electron Microscopic ◽  
Cell Complexes ◽  
Transmission Electron ◽  
Central Gland

Scanning electron microscopy of the body surface of the stonefly nymph, Taeniopteryx burksi, shows a characteristic pattern of folds bearing microtrichia. Interspersed among the microtrichia are trichoid sensilla, and bulbiform and hemispheroidal structures. The ultrastructure of the bulbous structure is similar to that of the chloride cell complexes of perlid and nemourid larvae. Three specialized epidermal cells were observed when the hemispheroidal structure was examined by transmission electron microscopy. The central gland cell encloses an apical cavity which leads into a curved epicuticular appendage with a terminal pore. The gland cell is surrounded by two specialized epidermal cells.

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