Effects of copper sulphate on in vitro encystment of the cercariae of Echinostoma caproni

2004 ◽  
Vol 78 (4) ◽  
pp. 371-372 ◽  
Author(s):  
B. Fried ◽  
J.L. Schneck
Keyword(s):  
Emergency Response ◽  
Cyst Wall ◽  
Copper Sulphate ◽  
Bile Salts ◽  
Spring Water ◽  
Echinostoma Caproni ◽  
Parorchis Acanthus ◽  
High Concentrations

AbstractThe effects of various concentrations of copper sulphate were studied on in vitro encystment of Echinostoma caproni in a Locke's–artificial spring water (ASW) (1:1) medium. Cercariae were killed in 10,000 mg l−1 CuSO4 in Locke's–ASW (1:1) within 24 h and extruded cystogenous material to produce an abnormal cyst wall. The ‘emergency response’ of encystment to high concentrations of copper reported for Parorchis acanthus cercariae did not occur in E. caproni. Concentrations of 1000 mg l−1 and 100 mg l−1 CuSO4 in Locke's–ASW (1:1) also killed the cercariae without encystment by 48 h. A concentration of 10 mg l−1 CuSO4 in Locke's–ASW (1:1) allowed for normal in vitro encystment within 48 h and these cysts were capable of excystation in a trypsin–bile salts medium.

Cercarial tail loss in Echinostoma caproni: the influence of in vivo encystment and copper sulphate

2005 ◽  
Vol 79 (2) ◽  
pp. 177-178 ◽  
Author(s):  
B. Fried ◽  
J.L. Schneck
Keyword(s):  
Copper Sulphate ◽  
Biomphalaria Glabrata ◽  
Spring Water ◽  
Echinostoma Caproni ◽  
Tail Loss ◽  
Water Ph

AbstractEchinostoma caproni tail loss was studied in vitro in the presence of the toxicant copper sulphate (CuSO4) in concentrations ranging from 1 to 10 000 mg l?1 in standardized artificial spring water (pH 7.4, osmolarity 34 mOsm kg?1 H2O, Ca2+ 20 mg l?1) at 23°C. Tail loss was also studied in the absence of toxicants during in vivo encystment of the cercariae in juvenile Biomphalaria glabrata. As the concentration of CuSO4 increased, the percentage of cercarial tail loss increased. By 2 h in 10 000 mg l?1, 1000 mg l?1 and 100 mg l?1 CuSO4, 50%, 23% and 13%, respectively, of the cercariae had lost their tails. In the in vivo studies, by 1 h PI, 59±5% of cercariae had lost their tails and only 4±1% of the cercariae were actively swimming in the multi-well dishes. At 3 h PI, 72±3% of the cercariae began to form cysts within the snails.

Changes in the Binding of Radioactive Conjugated Bile Salts to Serum Proteins in Cholestatic Jaundice

1983 ◽  
Vol 65 (1) ◽  
pp. 77-84 ◽  
Author(s):  
A. Chitranukroh ◽  
B. H. Billing
Keyword(s):  
Fatty Acids ◽  
Liver Disease ◽  
Bile Salts ◽  
Serum Proteins ◽  
Cholestatic Liver Disease ◽  
Normal Individuals ◽  
High Concentrations ◽  
Conjugated Bile Salts ◽  
Centrifugal Ultrafiltration

1. A micro-partition centrifugal ultrafiltration technique has been used to monitor the percentage of[14C]glycocholate,[3H]glycochenodeoxycholate and[3H]glycochenodepxycholate-3-sulphate bound to serum proteins of patients with cholestatic liver disease. 2. in comparison with normal individuals the percentage of binding of [14C]glycocholate and, to a lesser extent, of [3H]glycochenodeoxycholate and [3H]glycochenodeoxycholate-3-sulphate was reduced. 3. The binding of [14C]glycocholate was inversely related to the serum bile salt and bilirubin concentrations. in contrast, the binding of [3H]glycochenodeoxycholate and [3H]glycochenodeoxycholate-3-sulphate were not altered by the severity of the cholestasis. 4. Studies in vitro indicated that the reduction in the binding of [14C]glycocholate in cholestatic liver disease was not due to high concentrations of bile salts, unconjugated bilirubin or fatty acids.

Effects of temperature on survival, infectivity and in vitro encystment of the cercariae of Echinostoma caproni

2003 ◽  
Vol 77 (3) ◽  
pp. 235-238 ◽  
Author(s):  
B. Fried ◽  
E.L. Ponder
Keyword(s):  
Spring Water ◽  
Helisoma Trivolvis ◽  
Echinostoma Caproni ◽  
Maximal Life Span ◽  
Different Temperatures ◽  
Effects Of Temperature ◽  
Effects Of Aging ◽  
C 78 ◽  
Infective Period

AbstractThe effects of temperature on survival, infectivity and in vitro encystment of Echinostoma caproni cercariae in artificial spring water (ASW) were studied. Effects of aging cercariae in ASW at various temperatures showed that at 23°C cercariae achieved 50% survival in 24 h, compared to 92 h at 12°C. Cercariae aged in ASW at 28 and 37.5°C showed 50% survival at 16 and 10 h, respectively. Cercariae aged at different temperatures for various times were used to infect juvenile Helisoma trivolvis (Colorado strain) snails maintained in ASW at 23°C. Index of infectivity was based on counting encysted metacercariae in the snails at 8 to 12 h post-infection. Cercariae aged at 23, 28 and 37.5°C showed 50% encystment at 6, 8 and 4 h, respectively. Cercariae aged at 4°C showed 50% encystment in 10 h and cercariae aged at 12°C showed 50% encystment beyond 16 h. Cercariae showed maximal longevity and infectivity in snails when aged at 12°C in ASW. For E. caproni, as in other digeneans, the infective period of cercariae is markedly shorter than the maximal life-span at any given temperature. Studies on in vitro encystment of E. caproni cercariae in Locke's solution:ASW (1:1) showed that encystment was optimal at 23°C (78% encystment) and that it declined to 44% at 28°C and became almost nil (0.02%) at 12 or 37.5°C.

Light microscopic observations of Echinostoma caproni metacercariae during in vitro excystation

1995 ◽  
Vol 69 (3) ◽  
pp. 253-257 ◽  
Author(s):  
R.L. Ursone ◽  
B. Fried
Keyword(s):  
Light Microscopy ◽  
Bile Salts ◽  
Extrinsic Factors ◽  
Echinostoma Caproni ◽  
Allopatric Species ◽  
Saline Pretreatment ◽  
Intrinsic And Extrinsic Factors

AbstractLight microscopy was used to study excystation of Echinostoma caproni metacercariae in various media. Optimal excystation was observed in an alkaline trypsin-bile salts medium (TB) at 40 ± 1°C. The percentage of excystation in TB medium declined following either acid pepsin or acid saline pretreatment. Excystation rarely occurred in either trypsin or bile salts alone. Dissolution of the outer cyst occurred in TB medium thus facilitating excystation. Activation of the larva within the inner cyst led to its eventual release through an aperture in the mucoid plug region. Excystation of this species was facilitated by both intrinsic and extrinsic factors. There were considerable differences in excystation events between this species and the related allopatric species, E. trivolvis

Tributyltin and copper effects on encystment and in vitro excystment of Parorchis acanthus larvae

2003 ◽  
Vol 77 (4) ◽  
pp. 291-296 ◽  
Author(s):  
S.C. Bennett ◽  
S.W.B. Irwin ◽  
S.M. Fitzpatrick
Keyword(s):  
Emergency Response ◽  
Detrimental Effect ◽  
Lower Percentage ◽  
Natural Seawater ◽  
Nucella Lapillus ◽  
Larval Stages ◽  
Low Concentrations ◽  
Parorchis Acanthus ◽  
Copper Effects

AbstractEffects of tributyltin (TBT) and copper (Cu) on cercariae and metacercariae of the trematode Parorchis acanthus (Digenea: Philophthalmidae) were investigated. Cercariae released by the dogwhelk, Nucella lapillus were maintained in natural seawater (SW) or solutions of TBT or Cu ranging from 0.001–100 μg l−1 and 1–6 mg l−1 respectively before they encysted. Over 79% of the cercariae encysted in control and test solutions. Low concentrations of TBT reduced encystment success more than low concentrations of Cu. The percentage of cercariae that formed cysts in the highest concentrations of both pollutants was higher than in the controls, perhaps representing an ‘emergency response’ to the pollutants. Before being induced to excyst in vitro, metacercariae were left in the heavy metal solutions for 3 weeks. Metacercariae exposed as cercariae to TBT and Cu achieved lower percentage excystment success than those that had encysted in SW. Cyst walls provided greater protection against Cu than TBT. It was concluded that TBT and Cu had a detrimental effect on the larval stages of P. acanthus at the higher concentrations used but the cyst wall afforded an element of protection if formed in unpolluted seawater before the larval stages were subjected to the pollutants.

An in vitro study of the forcible ejection of the metacercaria of the strigeid digenean Apatemon (Australapatemon) minor Yamaguti, 1933 by rapid inward expansion of the cyst wall

1989 ◽  
Vol 63 (1) ◽  
pp. 63-71 ◽  
Author(s):  
G. C. Kearn ◽  
G. Cleveland ◽  
S. Wilkins
Keyword(s):  
Definitive Host ◽  
Cyst Wall ◽  
Bile Salts ◽  
In Vitro Study ◽  
Vitro Study ◽  
Metacercarial Cyst ◽  
A Minor

ABSTRACTIt has been established that the wall of the metacercarial cyst of the strigeid digenean Apatemon (Australapatemon) minor from the leech Erpobdella octoculata shares with Apatemon (Apatemon) gracilis the remarkable ability to expel the metacercaria forcibly from the cyst, an event which presumably occurs when the cysts are eaten by the bird definitive host. When cysts of A. minor are treated in vitro with a solution containing a mixture of bile salts and trypsin following pretreatment with acid pepsin, the metacercaria is expelled in an explosive manner through a canal at the narrow end of the pear-shaped cyst. This expulsion is produced by a sudden and substantial inward expansion of the birefringent wall, as a consequence of which the cyst lumen is virtually eliminated. Expulsion of the metacercaria in this explosive manner also occurs when similarly pretreated cysts are exposed to either bile salts alone or to trypsin, but cysts treated with the latter take longer to respond. When the cyst wall is perforated with a needle, inward expansion of the wall occurs and the metacercaria is forcibly ejected through the perforation. A variety of other pretreatments and treatments was tested but pepsin appears to be the most effective “primer”, apparently producing localized changes which permit the exit of the metacercaria. These observations are discussed in relation to the mechanism of expulsion.

In vitro excystment of the metacercaria of Bucephalus haimeanus from the common goby (Pomatoschistus microps)

1996 ◽  
Vol 70 (3) ◽  
pp. 193-200
Author(s):  
H. El-Mayas ◽  
G.C. Kearn
Keyword(s):  
Intermediate Host ◽  
Definitive Host ◽  
Cyst Wall ◽  
Bile Salts ◽  
Acidic Media ◽  
Distinctive Features ◽  
Second Intermediate Host ◽  
The Common ◽  
Common Goby

AbstractThe structure of the metacercarial cyst wall and excystment in vitro were studied in the bucephalid digenean Bucephalus haimeanus. Optimum excystment occurred in a mixture of 1% trypsin and 1% bile salts at pH 7.8, following a 15 min pretreatment with 1% pepsin at pH 2.0. Enzymes (pepsin, trypsin) facilitated excystment, but were not essential, since some of the active metacercariae perforated the cyst wall in their absence. Other distinctive features were the weak development of the cyst wall, the occurrence of some excystment in strongly acidic media, ability to survive for at least 2 h in acidic media (pH 2.0) and total inactivity and failure to excyst in bile salts. The possible significance of these features is considered in relation to the location of the cysts in the liver of the second intermediate host, the common goby (Pomatoschistus microps), and conditions experienced by the cysts when the goby is eaten by the definitive host, the bass (Morone labrax). Excystment occurred readily at temperatures from 10 to 40°C, but percentage and speed of excystment were reduced at 5°C.

In vitro excystment of the metacercaria of Cryptocotyle concavum from the common goby Pomatoschistus microps

1995 ◽  
Vol 69 (4) ◽  
pp. 285-297 ◽  
Author(s):  
H. El-Mayas ◽  
G.C. Kearn
Keyword(s):  
Electron Microscopy ◽  
Cyst Wall ◽  
Bile Salts ◽  
Anterior Extremity ◽  
Distilled Water ◽  
Transmission Electron ◽  
The Common ◽  
Common Goby ◽  
Wall Following

AbstractThe metacercaria of the heterophyid digenean Cryptocotyle concavum (Creplin, 1825) Lühe 1899, as seen by light and transmission electron microscopy, from the common goby (Pomatoschistus microps) is enclosed within a rigid cyst wall composed of four layers of parasite origin surrounded by a host-derived capsule. The encysted parasite contains anterior glands with secretion-filled ducts opening at the anterior extremity of the ‘head’. Excystment in vitro occurred most readily at 40–42°C on treatment with alkaline bile salts following pretreatment with acid pepsin. After 1 min in pepsin, the metacercaria became intermittently active, periods of rotation lasting 1–3 sec alternating with quiescent periods of 20–40 sec. Metacercariae excysted, some in less than 1 min, after transfer to bile salts. The metacercaria emerged through a hole, which appeared in the cyst wall at the site of application of the ‘head’ of the parasite. Some of the anterior gland ducts of excysted metacercariae were empty, indicating that their secretions are involved in penetrating the cyst wall. Following pretreatment in acid pepsin, no excystment occurred in EBSS (Earle's balanced salt solution) ranging in pH from 2.0 to 4.0, but above pH 4.0, excystment increased, reaching a maximum between pH 7.5 and 8.5. Pepsin and bile salts were not essential for excystment and metacercariae emerged, although less readily, in alkaline EBSS with or without acid EBSS pretreatment. Some emerged in distilled water with no pretreatment. Although no excystment occurred in acid pepsin or in EBSS at pH 2.0 and already-excysted metacercariae were rapidly killed by acid (pH 2.0), acid pepsin pretreatment enhanced excystment in alkaline bile salts.

In Vitro Effects of Ethanol on Rabbit Platelet Aggregation, Secretion of Granule Contents, and Cyclic AMP Levels in the Presence of Prostacyclin

1989 ◽  
Vol 61 (02) ◽  
pp. 254-258 ◽  
Author(s):  
Margaret L Rand ◽  
Peter L Gross ◽  
Donna M Jakowec ◽  
Marian A Packham ◽  
J Fraser Mustard
Keyword(s):  
Cyclic Amp ◽  
Inhibitory Effect ◽  
Rabbit Platelet ◽  
Inhibitory Effects ◽  
Low Concentrations ◽  
Rabbit Platelets ◽  
High Concentrations ◽  
In Vitro Effects ◽  
Aggregation Of Platelets

SummaryEthanol, at physiologically tolerable concentrations, inhibits platelet responses to low concentrations of collagen or thrombin, but does not inhibit responses of washed rabbit platelets stimulated with high concentrations of ADP, collagen, or thrombin. However, when platelet responses to high concentrations of collagen or thrombin had been partially inhibited by prostacyclin (PGI2), ethanol had additional inhibitory effects on aggregation and secretion. These effects were also observed with aspirin- treated platelets stimulated with thrombin. Ethanol had no further inhibitory effect on aggregation of platelets stimulated with ADP, or the combination of ADP and epinephrine. Thus, the inhibitory effects of ethanol on platelet responses in the presence of PGI2 were very similar to its inhibitory effects in the absence of PGI2, when platelets were stimulated with lower concentrations of collagen or thrombin. Ethanol did not appear to exert its inhibitory effects by increasing cyclic AMP above basal levels and the additional inhibitory effects of ethanol in the presence of PGI2 did not appear to be brought about by further increases in platelet cyclic AMP levels.

Aggregation of Cat Platelets in Vitro

1970 ◽  
Vol 23 (03) ◽  
pp. 601-620 ◽  
Author(s):  
Th. B Tschopp
Keyword(s):  
Adenosine Monophosphate ◽  
Blood Collection ◽  
Base Line ◽  
Reversible Aggregation ◽  
Low Concentrations ◽  
Irreversible Aggregation ◽  
High Concentrations ◽  
Two Phases ◽  
Improved Technique

SummaryAggregation of cat platelets in the citrated plasma is examined by means of Born’s absorptiometer. A marked tendency of the platelets of this species to spontaneous aggregation necessitated first of all the development of an improved technique of blood collection.A hypothesis according to which 5-HT is released from the platelets, explains the absence of oscillations on the base line of the absorptiometer, the absence of platelet swelling, when ADP is added, and the effect of stirring on the aggregation curves in cat PRP. The average volume of cat platelets amounts to 10.46 μ3 when directly fixed in the blood, when fixed from PRP to 12.17 μ3, when fixed from stirred PRP to 13.51 μ3.In low concentrations (0.3-2 μM) ADP produce reversible aggregation; in narrowly restricted, individually dissimilar mean concentrations irreversible aggregation in two phases and in high concentrations, irreversible aggregation in one phase. Like ADP serotonin produces 2 phase irreversible aggregation in concentrations of 3-10 μM, but unlike ADP, the aggregation velocity decreases again with high 5-HT concentrations (>100 μM). Adrenaline does not produce aggregation and it is likely that adenosine and adenosine monophosphate inhibit the aggregation by serotonin but not by ADP. Species differences in the aggregation of human, rabbit and cat platelets are discussed.

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