Light and scanning electron microscopical observations of the daughter rediae of Echinostoma trivolvis (Trematoda).
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Animals↗
Biomedical subjects
B Fried
Publications and source records attributed to B Fried.
The expulsion of Echinostoma trivolvis (Trematoda) from ICR mice: scanning electron microscopy of the worms.
Echinostoma trivolvis adults are rejected from ICR mice within 3 weeks postinfection (p.i.) but are retained in golden hamsters for greater than 15 weeks. The present study used scanning electron microscopy (SEM) to examine worm topography in ICR mice, particularly that of the collar spines, and to correlate worm loss with tegumentary changes. The topography of the worm in ICR mice was similar to that observed in previous studies on this echinostome in domestic chick embryos, chickens, and golden hamsters. Observations were made on the pattern of collar spines in 115 worms from ICR mice at 3-14 days p.i. All worms examined at 3 days exhibited extended spines, whereas about 70% of the worms examined at 14 days displayed retracted or missing spines. Eight worms from golden hamsters examined at 14 days p.i. showed extended collar spines. The retraction or loss of collar spines may play a role in the expulsion of E. trivolvis from ICR mice.
Animals↗
Use of an aceto-carmine procedure to examine the excysted metacercariae of Echinostoma caproni and E. trivolvis.
A simple aceto-carmine procedure was developed to relax, fix, stain, and clear excysted metacercariae of Echinostoma caproni and E. trivolvis. This procedure allowed for morphologic details on whole metacercariae comparable to those seen with more elaborate staining procedures. Differences in dimensions and staining intensities between the two species of metacercariae are described.
Animals↗
From front line to home front: a study of secondary traumatization.
While the long-term effects of combat trauma on veterans have been studied extensively, its impact on veterans' wives has yet to be investigated. This study examined the implications of combat-induced psychopathology--wartime combat stress reaction (CSR) and current posttraumatic stress disorder (PTSD)--in a sample of 205 wives of Israeli combat veterans of the 1982 Lebanon war. Results show that both CSR and PTSD were associated with increased psychiatric symptoms in the wives. In addition, current PTSD was particularly found to contribute to impaired social relations among veterans' wives in a broad range of contexts, from inner feelings of loneliness, through impaired marital and family relations, and extending to the wider social network. Implications of these findings for treatment and further research are discussed.
Analysis of Variance↗
Cultivation of excysted metacercariae of Echinostoma caproni to ovigerous adults in the allantois of the chick embryo.
Chemically excysted metacercariae of Echinostoma caproni inoculated into the allantois of domestic chick embryos became ovigerous in that site within 9 days postinoculation. The egg preparation technique of Saville and Irwin was markedly better than that of a modified Zwilling procedure for obtaining large numbers of postinoculation embryos with worm infections. Adults of E. caproni from the allantois were larger and became ovigerous sooner than worms grown on the chorioallantois. Only worms from the allantois produced eggs with fully developed miracidia. Miracidia were released from these eggs, but an insufficient number was available to attempt infections in Biomphalaria glabrata snails.
Allantois↗
Growth, development, pathogenicity, and transplantation of Echinostoma caproni (Trematoda) on the chick chorioallantois.
Excysted metacercariae of Echinostoma caproni were cultivated on the chorioallantoic membrane (CAM) of 6-day-old domestic chick embryos for 2-13 days postinoculation. There was no significant difference in the body area of fixed and stained preovigerous worms from the CAM versus those grown in domestic chicks. However, ovigerous worms from the CAM were significantly smaller than those from chicks. Worm development, i.e., gonadal differentiation, uterine curling, vitellinogenesis, ovigerousness, and oviposition, took 1 day longer on the CAM than in the chick. Histopathologic studies of worms attached to the CAM were done on cryostat and paraffin sections stained with hematoxylin and eosin. Some worms attached to the CAM by their collar spines and acetabulum, whereas others penetrated the chorionic epithelium and encapsulated in the mesenchyme. Pathogenicity to the CAM included hyperplasia of the chorionic epithelium, hemorrhagia, reduced fibrocytes and blood vessels, but increased lymphocytes and eosinophils in the mesenchyme. Attempts to transplant 11-day-old CAM worms to new CAMs were unsuccessful.
Allantois↗
The expulsion of Echinostoma trivolvis and retention of Echinostoma caproni in the ICR mouse: pathological effects.
The infectivity and distribution of Echinostoma trivolvis were studied in female ICR mice each infected with 25 metacercarial cysts. At 7 and 10 days post-exposure worm recoveries were 58.8 and 58.4%, respectively. Worm recovery declined to 38.2% by day 14, to 6.4% by day 21, and 0% by day 28. The distribution of the parasites demonstrated an anteriad shift over time. Comparative histopathological studies were carried out on E. trivolvis and Echinostoma caproni in the mouse. Compared to control and E. trivolvis-infected intestine, mouse intestine infected with E. caproni showed marked dilation and villous atrophy. E. trivolvis-infected intestine showed a nearly two-fold increase in goblet cells compared to control intestine, whereas the intestine of E. caproni-infected mice showed almost complete goblet cell loss. Additionally, there was a marked increase in collagen in the intestinal musculature of the mice infected with E. trivolvis compared to control and E. caproni-infected mice.
Animals↗
Schistosoma japonicum: changes in lipase activity in adults maintained in vitro.
Schistosoma japonicum (Chinese strain) adult worm pairs (10-12 weeks old) were fixed in 4 degrees C absolute acetone or neutral buffered formalin either immediately after recovery from mice, or following incubation for 0.5 or 1.0 h. Males and females were incubated individually in Earle's balanced salt solution at 37 degrees C. Lipase activity was determined in frozen sections by Gomori's method using Tween 80 as substrate. In unincubated males, lipase activity was localized only in the parenchyma; in females it was present in the vitellaria and parenchyma subjacent to the tegument. After 0.5 h incubation, males showed less lipase activity in the parenchyma than unincubated males, and females showed increased activity in the parenchyma subjacent to the tegument, but not in the vitellaria. Following 1.0 h incubation, males showed less lipase activity than previously, and females showed a marked increase in activity, particularly in the parenchyma subjacent to the tegument.
Animals↗
Concurrent infections of Echinostoma caproni and Echinostoma trivolvis in ICR mice.
ICR female mice, 6- to 8-weeks old, were exposed concurrently to 25 metacercarial cysts of Echinostoma caproni and 25 metacercarial cysts of Echinostoma trivolvis and necropsied 10 and 14 days post-infection. Controls consisted of mice exposed singly to either 25 or 50 E. caproni or E. trivolvis cysts. All 23 mice exposed to E. caproni cysts were infected with a total of 331 worms (37.8%), whereas only 11 (37.9%) of 29 mice exposed to E. trivolvis cysts were infected with a total of 77 (6.4%) worms. In the concurrent infections, 13 (59.1%) of 22 mice were infected with both species and the percentage of worm recovery was 72.6% for E. caproni and 14.2% for E. trivolvis. There was no difference in worm distribution of either species in single vs concurrent infections. In concurrent infections at 14 days PI, there was a significant decrease in the body area of worms of both species, when compared to single worm species.
Animals↗
Effects of host age on infection of ICR mice with Echinostoma caproni or E. trivolvis.
There was no significant difference in the number of E. caproni recovered 21 days post-infection from 1-, 2-, 4-, 5-, 6-, 7-, 12-, or 21-month-old ICR mice infected with 25 metacercarial cysts. A range of 10.8-17.3 worms was recovered from mice in the age groups. In a similar experiment with E. trivolvis, there was no significant difference in worms recovered in young vs old mice. A range of 0-1.7 worms was recovered from mice in each age group. Contrary to a previous study on E. caproni in NMRI mice, our results indicate that host age does not affect establishment of E. caproni or E. trivolvis in the ICR mouse.
Age Factors↗
Reversal of dietary-induced hyperlipidemia in Biomphalaria glabrata (Gastropoda).
1. To determine if dietary induced hyperlipidemia in snails could be reversed, thin-layer chromatography studies were done on lipids in the digestive gland-gonad (DGG) complex of Biomphalaria glabrata fed either hen's egg yolk for 2 weeks (Group A), yolk for 1 week followed by leaf lettuce for 1 week (Group B), or lettuce for 2 weeks (Group C). 2. The major lipid fractions in Group A were triacylglycerols, phosphatidylethanolamine, and phosphatidylcholine, along with lesser amounts of sterol esters, methyl esters, free fatty acids, free sterols and unidentified phospholipids. 3. Groups B and C had about one-half the amount of triacylglycerols than Group A and did not show sterol esters or methyl esters. 4. The triacylglycerol increase of the DGG resulting from the hen's egg diet could be reversed by returning the snails to the lettuce diet.
Animals↗
The effects of crowding on adults of Echinostoma caproni in experimentally infected golden hamsters.
Fifty-nine of 60 (98%), 6-month-old male golden hamsters, Mesocricetus auratus, fed 15 (group A), 50 (group B), or 200 (group C) metacercarial cysts of Echinostoma caproni (Digenea: Echinostomatidae) were infected 7-34 days postexposure. The mean number of worms recovered in groups A, B and C were 9, 10, and 50, respectively. The percentage recovery was significantly different between group A (63%) and groups B (21%) and C (23%). The intestine was divided into three equal regions (I, II, III). Worms from group A were located in segments II and III of the small intestine whereas worms from groups B and C were distributed in all three segments. The body area, ovarian and testicular areas of worms from group A were greatest, followed in decreasing order by body and gonadal areas of worms from groups B and C. Echinostoma caproni eggs were found in the faeces of all the hamsters examined from groups A, B and C by days 9, 10 and 11, respectively. Physical damage occurred at the site of attachment of the echinostome. Pathological observations indicated the presence of enlarged lymphatic nodules with lymphocytes being the primary cellular infiltrate at the site of parasite attachment.
Animals↗
Scanning and transmission electron microscopical observations on the tegument of excysted metacercariae and adults of Zygocotyle lunata.
Scanning and transmission electron microscopical observations were made on the tegument of excysted metacercariae and adults of the paramphistome, Zygocotyle lunata (Digenea: Trematoda). In accord with other paramphistomes studied, this species lacks spines and mitochondria in the tegumentary syncytium and associated cytons. The newly excysted metacercarie, which possessed relatively few tegumental papillae, were cylindrical in comparison to adults which were distinctly flat. The adults had large numbers of tegumental papillae in the region of the oral sucker and acetabulum.
Animals↗
A comparison of Echinostoma caproni and Echinostoma trivolvis (Trematoda: Echinostomatidae) adults using isoelectrofocusing.
An isoenzymatic analysis using thin-layer agarose gel isoelectrofocusing on laboratory strains of Echinostoma trivolvis and Echinostoma caproni adults showed characteristic monomorphic phenotypes for phosphoglucomutase and glucose phosphate isomerase. The fixed allelic variation observed between these 2 taxa is consistent with their current classification as distinct species.
Alleles↗
Cultivation of excysted metacercariae of Echinostoma caproni (Trematoda) to ovigerous adults on the chick chorioallantois.
Excysted metacercariae of Echinostoma caproni were cultivated on the chick chorioallantoic membrane (CAM) maintained at 38.5 +/- 1 C and a relative humidity of 60-65%. Of 59 6-day-old embryos, each inoculated with 25 metacercariae, 29 (49.2%) were infected 2-12 days postinoculation. The total number of worms recovered from the infected eggs was 163 or 22.5% of the 725 inoculated metacercariae. Eggs contained from 1 to 12 (average 5.6) worms per CAM. Worm length increased rapidly from an average of 0.5 mm at 2 days to about 3.0 mm at 6 days postinoculation. Ovigerous worms first were seen on day 8 PI, but fluke eggs did not develop embryos. Worm development in ovo lagged about 1 day behind that of in vivo worms. One worm maintained for 17 days on 2 successive CAMs reached 6 mm in length, contained about 100 eggs in its uterus, and laid an additional 100 eggs on the CAM surface.
Allantois↗
Infectivity, growth, and distribution of Echinostoma caproni (Trematoda) in the ICR mouse.
Host-parasite interactions of the intestinal trematode Echinostoma caproni were studied in ICR laboratory mice. All of 40 mice, each fed 25 metacercarial cysts of Echinostoma caproni, were infected 1-20 wk postinfection (PI) with a mean of 17.2 worms/host. At 24 and 29 wk PI only 2 of 6 mice (33%) were infected, with a mean of 4.2 worms/host. Mean body area of worms increased rapidly to about 5 mm2 by week 2, increased less rapidly to 8.8 mm2 by week 12, plateaued until week 24, and then declined. Mean dry weight of worms increased rapidly to about 0.5 mg by week 2, less rapidly to 1.4 mg by week 12, and then plateaued until week 24 PI. From 1 to 8 wk PI most worms localized in the jejunum and ileum; later most worms were in the jejunum and duodenum. Considerable differences were seen in the growth and distribution of E. caproni in the ICR mouse compared with previous studies on this echinostome species in the NMRI mouse.
Animals↗
Exposure of Dugesia tigrina (Turbellaria) to cercariae of Echinostoma trivolvis and Echinostoma caproni (Trematoda).
Laboratory-reared planarians, Dugesia tigrina, were exposed to cercariae of Echinostoma trivolvis or Echinostoma caproni. Of 100 D. tigrina exposed to 2,750 cercariae of E. trivolvis, 29 were infected with a total of 85 encysted metacercariae 24 hr postinfection (PI). None of 40 D. tigrina exposed to 1,100 cercariae of E. caproni was infected with metacercariae 24 hr PI. Cyst structure of E. trivolvis from the parenchyma of D. tigrina varied from normal to abnormal. Metacercariae removed from planarians could be excysted in an alkaline trypsin-bile salts medium. Cercariae of E. trivolvis were not attracted to dialysate material from D. tigrina. Cercariae of E. trivolvis that penetrated, but did not encyst in planarians, voided the contents of their paraesophageal glands. Cercariae of E. caproni lack paraesophageal glands. Secretions of those glands probably are involved in tissue penetration of D. tigrina by E. trivolvis cercariae.
Animals↗
Infectivity, growth, survival, and pathogenicity of Zygocotyle lunata (Trematoda) in experimental rodent hosts.
Laboratory mice, rats, and golden hamsters were fed metacercarial cysts of Zygocotyle lunata to examine infectivity, growth, survival, and pathogenicity of this trematode. All 3 rodent types became infected with Z. lunata. Eggs of Z. lunata were seen in the feces of the hamsters by day 21, in mice by day 26, and in rats by day 44. Eggs teased from worms and embryonated in tap water hatched from day 21 to day 26 for rats and mice and from day 40 to day 45 for hamsters. The body areas of sexually mature worms were similar in all 3 types of rodent species. It was possible to reinfect all 3 species with Z. lunata metacercariae. No sign of clinical amphistomiasis was evident in the experimental animals. The histopathological responses were progressive, and severity was related to the age of the infection and the number of worms in the infection.
Animals↗