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P Deplazes

Publications and source records attributed to P Deplazes.

At least 109 records · Page 6Linked to original sources
PubMed1994

Detection of Septata intestinalis in stool specimens and coprodiagnostic monitoring of successful treatment with albendazole.

We describe two patients with AIDS and chronic diarrhea in whom the microsporidian Septata intestinalis was detected with use of light and electron microscopic coprodiagnostic techniques. The ultrastructure of the microsporidian spores found in their stool specimens was distinctly different from that of Enterocytozoon bieneusi, another intestinal microsporidian found in patients infected with human immunodeficiency virus. Electron microscopic examination of duodenal biopsy specimens available from one of the patients enabled identification of S. intestinalis and confirmed the similarity of spores found in feces and in duodenal tissue. Both patients' diarrhea stopped when they were treated with albendazole. Coprodiagnostic monitoring indicated disappearance of the parasites and allowed the diagnosis of a relapse in one patient, who responded well to a second course of treatment.

AIDS-Related Opportunistic Infections↗
PubMed1994

Detection of Echinococcus coproantigens in stray dogs of northern Spain.

An enzyme-linked immunosorbent assay (ELISA) was assessed for its suitability to diagnostically detect Echinococcus coproantigens in fecal samples of dogs infected with E. granulosus. The specificity of the test was determined by investigating fecal samples from 177 Echinococcus-free dogs infected with Taenia spp., 41 dogs with non-taeniid helminths and 24 dogs free of helminth infections. An overall specificity of 97% was determined. The diagnostic sensitivity was in close association to the worm burden of infected individuals: when dogs harboured less than 100 worms, six from 21 samples (29%) were found to be positive in coproantigen ELISA, whereas sensitivity was much higher (23 ELISA-positive from 25 samples = 92%) when dogs had more than 100 worms. Despite the relatively low average sensitivity (63%), the test enabled detection of more than 90% of the biomass of adult Echinococcus present in the respective dog populations. Conclusively, coproantigen detection allows diagnosis of most individual intestinal Echinococcus infections relevant for the egg contamination of the environment and is therefore a valuable tool to determine the relative prevalence of adult stage E. granulosus prevalence in a given endemic area.

Animals↗
PubMed1994

[Case report: dirofilariasis in a dog].

A Siberian Husky from the Milan region was referred to the Clinic for clarification of a history of weight loss and rapid fatigue. On clinical examination increased vesicular sounds and dyspnea after physical excitement and effort were the only abnormal findings demonstrable. Radiologically demonstrated changes of the pulmonary arteries led to a tentative diagnosis of Dirofilariosis. The parasitological diagnosis based on serology and the morphology of microfilariae isolated from the blood indicated an infection by microfilariae and adult stages of Dirofilaria immitis. After premedication with Aspirin, the patient was treated against adult filariae with Caparsolate, and a month later with Ivermectin against the microfilariae. At the time of reexamination, 5 months after initiation of therapy, the dog was clinically healthy and free of any demonstrable infection with Dirofilaria. In a second, clinically normal Husky from the same kennel, isolated Dirofilaria repens microfilariae were demonstrated. This dog was not treated.

Animals↗
PubMed1993

In vitro synthesized immunoglobulin A from nu/+ and reconstituted nu/nu mice against a dominant surface antigen of Giardia lamblia.

Nu/+ mice (ZU.ICR-strain) experimentally infected with Giardia lamblia (clone GS/M-83-H7) cleared the infection by day 45 postinfection (p.i.). Athymic nu/nu mice were reconstituted with immune Peyer's patch lymphocytes obtained from self-healed nu/+ littermates and thus acquired the potential to decrease their intestinal parasite mass. Intestinal B-cells from self-healed nu/+ mice as well as from immune-reconstituted athymic nude mice synthesized in vitro parasite-specific immunoglobulin A (IgA). This IgA was subsequently analyzed by immunoblotting, showing a predominant reaction with the major surface antigen (a 72,000-Da polypeptide) characterizing the Giardia clone in question. The hypothesis on the causative role of intestinal IgA and immune lymphocytes in the control of G. lamblia infection thus deserves further attention.

Animals↗
PubMed1992

Echinococcus multilocularis: immunological study on the "Em2-positive" laminated layer during in vitro and in vivo post-oncospheral and larval development.

Echinococcus multilocularis oncospheres, primary vesicular cysts, and protoscolices were assessed in vitro and in vivo for their potential to synthesize a PAS-positive laminated layer containing monoclonal antibody (mAb) G11-binding Em2 antigen. The presence of Em2 antigen in developed oncospheres and cysts was subsequently correlated to the potential of in vivo development into a secondary metacestode in recipient host mice, which also responded by anti-Em2 serum antibody formation. In contrast, protoscolices failed to develop the "Em2-positive" layer in vitro under the selected experimental conditions. The failure to develop subsequently in vivo into a secondary metacestode was underlined by a lack of anti-Em2 serum antibody formation by the hosts. We furthermore developed a technique to obtain E. multilocularis clones by inoculating single oncospheres into recipient mice.

Animals↗
PubMed1992

Detection of Echinococcus coproantigens by enzyme-linked immunosorbent assay in dogs, dingoes and foxes.

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of Echinococcus coproantigens in fecal samples from dogs, dingoes or foxes infected with either E. granulosus or E. multilocularis. The ELISA was based on protein-A-purified polyclonal antibodies [anti-E. granulosus excretory/secretory (E/S) antigens]. The specificity of the assay as determined in 155 samples derived from carnivores that were free of helminth infection (n = 37) or infected with non-Echinococcus cestodes (n = 76) or with various nematodes (n = 42) was found to be 98% overall. The diagnostic sensitivity was strongly dependent on the homologous worm burden. All 13 samples from foxes harboring greater than 1,000 E. multilocularis worms and 13 of 15 (87%) samples from dogs or dingoes containing greater than 200 E. granulosus worms were ELISA-positive, whereas 34 of 46 samples from foxes harboring less than 1,000 E. multilocularis and 9 of 10 samples from dogs or dingoes bearing less than 200 E. granulosus tested negative. Experimental prepatent infections of dogs with E. granulosus revealed positive ELISA reactions within the prepatent period (10-20 days post-infection) for six animals bearing greater than 1,000 E. granulosus each; a low worm burden (less than 1,000 tapeworms/animal) resulted in ELISA positivity in only 2 of 3 animals at 30 days post-infection at the earliest. All five dogs that had been experimentally infected with E. multilocularis tested positive in the coproantigen ELISA as early as on day 5 post-infection.

Animals↗
PubMed1992

[Parasitological and immunological progress control during and after chemotherapy of canine leishmaniasis].

Promastigote Leishmania-organisms were diagnostically cultivated in vitro from popliteal lymph node aspirates obtained from 32 of in total 36 dogs returning from endemic areas. Isoenzyme analysis (glucosephosphate-isomerase (GPI), phosphoglucomutase (PGM) and glutamate-oxaloacetate-transaminase (GOT) resulted in the identification of Leishmania infantum (syn. Leishmania (L.) infantum) for all 18 isolates investigated. Parasites were still able to be cultivated in vitro in 79% of 28 biopsies (from 15 dogs) even following chemotherapy by Glucantime, independent of the time of sampling and the course of disease after treatment. Dogs with a progressive form of disease (despite chemotherapy) showed only a minor or no reduction (between 0 and 4.8%) of the relative antibody concentration (determined by ELISA), whereas regressive forms of disease (without recurrences observed in the period of 10 to 37 months after therapy) demonstrated a marked reduction of the relative antibody concentration (between 6.7 and 16.2%) within the first 5 to 8 months; thereafter the decrease diminished and changed to a persistent low relative antibody concentration.

Animals↗
PubMed1991

A monoclonal antibody against Echinococcus multilocularis Em2 antigen.

A monoclonal antibody (MAb G11) species-specific to the Em2 antigen of Echinococcus multilocularis was generated for (i) further biological characterization of the Em2 antigen, (ii) easy affinity-purification of Em2 antigen for immunodiagnostic and immunological investigations and (iii) development of a sandwich-ELISA for the detection of Em2 antigen in diagnostic samples and thus species-specific identification of E. multilocularis metacestode material. The MAb G11 was used in an antibody sandwich-ELISA to detect soluble Em2 antigen with a methodical sensitivity of 80 ng E. multilocularis antigen/ml of solution. MAb G11 specifically detected Em2 antigen in all of 15 E. multilocularis-isolates originating from various geographical areas and in none of other helminth isolates (e.g. Echinococcus granulosus, E. vogeli, and others). Further biological analysis by FITC-labelled MAb G11 demonstrated unique binding activity to the laminated layer of the metacestode. Also, oncospheres were binding FITC-labelled MAb G11 on an outer layer synthesized during cultivation in vitro for 13 days after hatching. Application of the MAb G11 antibody sandwich-ELISA for investigation of solubilized oncospheres confirmed the in vitro synthesis of Em2 antigen by oncospheres on day 13 p.i. Adult stages (somatic antigens) and freshly hatched oncospheres were always MAb G11 negative. Solid-phase MAb G11 was used for purification of the corresponding Em2 antigen by affinity chromatography. A preliminary serological evaluation of the Em2(G11) antigen by ELISA revealed identical immunodiagnostic characteristics, compared to Em2 obtained by classical means, thus suggesting the presented method for future isolation of large-scale Em2 antigen.

Animals↗
PubMed1991

Serological (Em2-ELISA) and parasitological examinations of fox populations for Echinococcus multilocularis infections.

Serum or body fluid samples of 1,006 foxes were investigated in an ELISA for antibodies against a highly sensitive and specific antigen (Em2-antigen) of Echinococcus multilocularis. Parasitological examinations of the intestines and simultaneous serological examinations were carried out in 505 foxes: A group of 98 blue foxes (Alopex lagopus) from Norwegian fox farms did not contain intestinal stages of E. multilocularis and was clearly sero-negative in Em2-ELISA. On the other hand in red foxes (Vulpes vulpes) originating from European areas known to be endemic for E. multilocularis the following average prevalence rates were found: 244 foxes from Southern Germany, E. multilocularis prevalence 55% and sero-prevalence 60%; 139 foxes from Austria, E. multilocularis prevalence 4% and sero-prevalence 12%. Serological identification of individual foxes with or without intestinal E. multilocularis infection was not possible. Only serological (no parasitological) examination in 402 foxes originating from endemic areas in Switzerland resulted in a sero-prevalence rate of 37%. Sero-prevalence was only 6% and 4% in 54 and 26 other foxes, respectively, originating from Swiss and German areas where E. multilocularis has not yet been reported. Negative control Norwegian (farmed) silver foxes (n = 43) were all sero-negative. The specificity of the Em2-ELISA was confirmed by negative Em2-serologies with sera from dogs infected with intestinal and tissue dwelling helminth species (with the exception of two from 24 dogs infected with E. granulosus).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Detection of Taenia hydatigena copro-antigens by ELISA in dogs.

A sandwich-ELISA was developed for the detection of soluble Taenia hydatigena antigens in fecal samples of dogs. Affinity-purified polyclonal catching antibodies and alkaline phosphatase-conjugated detecting antibodies were employed, which had been obtained from rabbits hyperimmunized with excretory/secretory antigens derived from in vitro maintained adult Taenia hydatigena. The assay allowed the detection of 800 ng T. hydatigena antigen g-1 of feces as a lower limit. Six helminth-free dogs were each infected with 10 T. hydatigena cysticerci isolated from Swiss sheep. After prepatent periods ranging from 57 to 71 days, the dogs started to excrete Taenia eggs and/or proglottids. The ELISA detected Taenia antigens in all six dogs during the prepatent period starting individually between Day 18 and 45 post-infection (p.i.). Anthelmintic treatment of three dogs at Day 95 p.i. resulted in elimination of the cestodes and within the 5 following days in the disappearance of Taenia antigens from feces. The specificity of the assay was evaluated by testing crude antigens derived from helminths or bacteria. Four Taenia species showed cross-reactivity at concentrations of 5 micrograms protein ml-1. Conversely, no cross-reactions occurred with various antigen batches derived from Echinococcus granulosus, E. multilocularis, Dipylidium caninum, Mesocestoides corti, Diphyllobothrium sp., Toxocara canis and bacterial antigens (Salmonella and Escherichia). Moreover, fecal samples from dogs naturally infected with T. canis (n: 13), hookworms (n: 2), Trichuris vulpis (n: 13) and of 10 dogs with mixed infections with these three nematode groups were tested, and results confirmed the high degree of specificity. The Taenia antigens detectable by this ELISA remained immunologically stable in native feces stored at +25 degrees, +4 degrees or at -20 degrees C for at least 5 days.

Animals↗
PubMed1990

Uniform strobilar development of Echinococcus multilocularis in vitro from protoscolex to immature stages.

The aim of this study was to obtain uniformity in strobilar development of Echinococcus multilocularis from protoscoleces in vitro. The isolate of E. multilocularis used was derived initially from a human case in France and subsequently maintained in the laboratory by intraperitoneal passage in Meriones unguiculatus. Protoscoleces used for culture were obtained using preparative procedures in which parasite tissue was disrupted gently with minimal exposure to pepsin and acidic conditions followed by immediate exposure to pancreatin in alkaline solution. Resultant cultures contained large numbers of evaginated, active, vermiform stages, which exhibited uniform strobilar development with formation of the first proglottid and segment and limited maturation of the first proglottid. All worms that exhibited proglottization subsequently segmented. Further proglottization did not occur and all worms degenerated within a few days following segmentation. The results are discussed in light of current knowledge of the relationships of somatic and germinal processes in Echinococcus. In view of these results, further studies should be encouraged to improve strobilar development of E. multilocularis in vitro.

Animals↗
PubMed1989

[Indirect detection of the infectious agents of selected parasitic diseases in animals by immunologic and molecular biological methods].

In this review the following possibilities of indirect detection of causal agents in selected animal parasitoses are discussed: Detection of serum antibodies by ELISA, IFAT and other test systems in leishmaniasis of dogs, babesiosis of horse, cattle and dog, and in toxoplasmosis of cat and various intermediate host species. In leishmaniasis of dogs the specificity of serodiagnosis can be improved by additional Western-Blot analysis. New approaches are provided by the detection of antigens circulating in serum (i.e. in dirofilariasis of dogs) or excreted in faeces (copro-antigens) (i.e. in intestinal parasitoses). Some of the last mentioned techniques are still under evaluation. A new trend in the diagnosis of parasitoses is the application of DNA technologies for the specific identification of causal agents. Some examples are discussed.

Animals↗