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J Eckert

Publications and source records attributed to J Eckert.

At least 73 records · Page 4Linked to original sources
PubMed1996

Cestodes. Echinococcus.

This article deals with cystic echinococcosis (CE) and alveolar echinococcosis in humans caused by the cestode parasites Echinococcus granulosus and Echinococcus multilocularis. The life cycles of these parasites and their epidemiologic aspects are briefly discussed, and a detailed review is presented on clinical aspects of the diseases, including diagnosis and therapy. Considerable progress has been made in chemotherapy but the results are not yet satisfactory. A new alternative for treatment of CE is puncture of cysts, aspiration of fluid, injection of ethanol, and reaspiration of fluid (PAIR).

Animals↗
PubMed1996

An improved test system for PCR-based specific detection of Echinococcus multilocularis eggs.

For the sensitive detection of eggs of Echinococcus multilocularis in fox faeces by PCR we have evaluated a method based on the previous concentration of helminth eggs by a combination of sequential sieving of faecal samples and flotation of the eggs in zinc chloride solution. The eggs were microscopically detected in the fractions retained in 40 and 20 microns mesh sieves. DNA of the taeniid eggs retained in the 20 microns sieve was obtained after alkaline lysis and PCR was performed using E. multilocularis species-specific primers. Compared to the parasitological findings after examination of the small intestines of the foxes, the specificity of the PCR was 100% (no false-positive result with 20 foxes free of E. multilocularis) and the sensitivity was 94% (33 positive results from total 35 foxes proven to be infected with E. multilocularis). Both false-negative results were obtained with faeces from foxes harbouring immature worms. Using faecal volumes between 2 and 20 ml, no inhibition of PCR was observed as was demonstrated by the amplification of size-modified target in parallel reactions. The tests were undertaken with fresh faeces stored in 70% ethanol, but egg detection by PCR was also possible after inactivation of eggs by freezing the faeces at -80 degrees C for one week or by incubation at +70 degrees C for 2 h.

Animals↗
PubMed1996

[PCR for detection and characterization of parasites (Leishmania, Echinococcus, Microsporodia, Giardia)].

The application of PCR for the diagnosis and the characterisation of parasites is discussed using four examples. (1) A PCR assay that was developed for the detection of Leishmania was shown to be as highly sensitive as in vitro cultivation of the parasites from lymph node aspirates and bone marrow biopsies. (2) Single eggs of Echinococcus multilocularis can principally be detected and identified by PCR. However, a cumbersome sample preparation is inevitable in order to remove PCR-inhibitory substances present in fox faeces. (3) Analysis of the amplified SSU rRNA gene of Encephalitozoon-like isolates from humans, rabbits and farm foxes confirmed for the first time that E. cuniculi-isolates from humans and animals are indistinguishable and that they are of importance as opportunistic parasites in HIV-infected patients. (4) Swiss isolates of Giardia originating from humans, calves, sheep and a dog could be allocated into three distinct genetic groups by analysing several PCR-amplified genes that encode for variant-specific surface proteins. There was no evidence for the presence of host-specific genotypes.

AIDS-Related Opportunistic Infections↗
PubMed1996

[Vaccines against parasitic diseases of domestic animals].

This review presents short information on the present status and some future perspectives of vaccination against parasitoses of domestic animals. For the control of such parasitoses in some European countries only a few vaccines are registered: Paracox and Livacox (for coccidiosis in chickens), Toxovax (for toxoplasmosis in sheep), Pirodog (for babesiosis in dogs) and Dictol (for dictyocaulosis in cattle). These are live vaccines containing attenuated parasites, except Pirodog. As a world-wide innovation in 1994 a vaccine against ixodid tick infestation (Boophilus microplus) in cattle was marketed in Australia under the trade name TickGARD which contains a recombinant protein antigen. A recombinant vaccine against Taenia ovis cysticercosis in sheep was developed in Australia/New Zealand but has not yet been registered. The development of vaccines against further parasitoses of domestic animals is a fascinating and promising field. Present research activities are focussed on molecular antigen vaccines and vector vaccines. First reports (for example regarding leishmaniosis and malaria) indicate that nucleic acid vaccines represent a new potential of development.

Animals↗
PubMed1996

Diagnosis of the Echinococcus multilocularis infection in final hosts.

In view of the considerable public health significance of Echinococcus multilocularis, the causative agent of the highly lethal human alveolar echinococcosis, there is an urgent need for reliable and simple techniques for the diagnosis of the infection in populations of final hosts (foxes, dogs, cats) and also in individual dogs and cats. The standard technique presently used is parsitological examination of the small intestine at necropsy. This reliable technique requires high expenditure and special safety precautions. An alternative approach is coproantigen detection. Recently, in our laboratory an ELISA was evaluated using rabbit and chicken polyclonal antibodies against E. multilocularis antigens (affinity purified coproantigens and somatic adult worm antigens). The specificity of this test (evaluated in 20 foxes and 661 dogs with helmintic infections other than E. multilocularis) was very high (95%-99.5%). Average sensitivity in 35 foxes infected with E. multilocularis was 80%, but reached 93% in foxes with individual worm burdens over 55. A Polymerase Chain Reaction (PCR) was used for detecting DNA of E. multilocular is in faecal samples of foxes after the parasite eggs had been isolated by a sieving procedure. In a total of 55 foxes specificity was 100% and sensitivity 94%. For field application the coproantigen ELISA has the potential of replacing parasite detection at necropsy, and PCR is a valuable method for confirmation of positive coproantigen results and for diagnosis in individual animals. Detection of circulating anti-Em2 antibodies by ELISA may be useful for primary screening of fox populations but antibody prevalence rates do not correlate with prevalence rates of the intestinal infection with E. multilocularis.

Animals↗
PubMed1995

[Human echinococcosis in Switzerland, 1984-1992].

In a retrospective study (1984-1992), new cases of human echinococcosis were registered in Switzerland based on information obtained from (a) questionnaires sent to 294 of the 300 acute hospitals in all parts of the country and to 17 institutes of pathology (268 answers form hospitals: 91%), and (b) from tracing back cases reported under the official notification system since 1 January 1988 by laboratories to the Federal Health Office or recorded at the Institute of Parasitology in Zurich. Cases were regarded as verified if the diagnosis was documented by unequivocal findings (by radiology, ultrasonography, pathomorphology etc. and often by additional detection of anti-Echinococcus antibodies). Patients with antibodies but without reports on further findings were classified as suspected cases. From 1984 to 1992 (9 years), 302 new cases of human echinococcosis were diagnosed in Switzerland and verified in this study, corresponding to an annual average of 34 new cases and a range between 26 and 43 cases. The total number of 302 cases included 228 (75%) of cystic echinococcosis (CE) (Echinococcus granulosus), 65 (22%) of alveolar echinococcosis (AE) (E. multilocularis), and 9 (3%) of non-specified echinococcosis (NSE) (Echinococcus sp.). Among 185 patients with CE and 60 patients with AE and known geographic origin, the ratio of Swiss nationals to foreigners was 25%:75% and 88%:12% respectively. Based on a total population (Swiss nationals and foreigners) of 6.62 million in 1988 and the case numbers of 1984-1992, the following average annual incidence rates per 100,000 inhabitants were calculated: 0.51 for all new cases, 0.38 for CE, 0.11 for AE and 0.01 for NSE. In the 37 years since 1956 there has been steady increase in new cases of CE due to the importation of such cases by foreigners, whereas the case numbers of AE have remained nearly constant with a range between 7 and 10 new cases per year. In our study 258 suspected seropositive patients were registered but not added to the total number of cases, due to the lack of further findings.

Adolescent↗
PubMed1995

Catatonia: short-term response to lorazepam and dopaminergic metabolism.

Therapeutic response to lorazepam and dopaminergic metabolism were investigated in 18 neuroleptically naive acute catatonic patients. They were diagnosed as catatonic according to criteria by Lohr and Rosebush and treated exclusively with lorazepam (2-4 mg) during the first 24 h. Dopaminergic metabolism (plasma HVA, plasma MHPG), anxiety (HAM-A) and parkinsonic/dyskinetic movements (SEPS, AIMS) were measured under standard conditions before initial treatment with lorazepam (day 0) and 24 h after initial treatment (day 1). On day 0 responders to lorazepam treatment (complete remission of catatonic syndrome after 24 h according to Rosebush and Lohr) showed significantly higher (P = 0.004) plasma HVA (130.4 +/- 51.2 pmol/ml; means +/- SD) than non-responders (no remission of catatonic syndrome after 24 h; 73.2 +/- 40.5 pmol/ml; means +/- SD). On day 1 plasma HVA did not differ any more significantly between both groups Clinically, responders showed significantly higher HAM-A (P = 0.025) and AIMS (P = 0.022) scores as well as significantly lower SEPS (P = 0.049) scores than non-responders on day 0. Hence catatonic short-term responders and nonresponders to lorazepam can be distinguished with regard to plasma HVA, anxiety and dyskinetic/parkinsonic movements.

Acute Disease↗
PubMed1995

Pathophysiological studies of sheep during the build-up of immunity against Ostertagia leptospicularis and after a challenge infection.

Four groups of three lambs were used to investigate the pathophysiological changes during the development of a protective immunity against Ostertagia leptospicularis induced by a trickle infection. Three groups (A, B and C) were infected daily with 1000 third-stage larvae (L3) for a period of 26 weeks; group D remained uninfected until challenged. Egg excretion ceased after about 10 weeks in groups A, B and C and at the end of the trickle infection no parasites were found in group A sheep after slaughter. The sheep of groups B and C were highly refractory to two challenge infections, with 100,000 and 200,000 L3, given four and 17 weeks after the end of the trickle infection. Both challenge infections were followed by short term increases in the concentrations of gastrin and pepsinogen in the serum. Group C sheep were immunosuppressed with flumethasone during the second larval challenge and had higher pepsinogen concentrations but similar gastrin concentrations to the untreated sheep of group B.

Animals↗
PubMed1995

In vitro maturation, fertilization and culture to blastocysts of bovine oocytes in protein-free media.

This study examined the role of protein supplementation at the various steps of the in vitro production of bovine embryos derived from two different morphological categories of COC. The basic medium was TCM 199 and was supplemented with hormones during maturation in vitro and either estrous cow serum (ECS), bovine serum albumin (BSA) at various concentrations or polyvinyl-alcohol (PVA). Fertilization in vitro was carried out using frozen-thawed semen or one bull in Fert-talp containing heparin, hypotaurin and epinephrine and either 6 mg/ml BSA or 1 mg/ml PVA. In vitro culture up to the blastocyst stage was performed in TCM 199 supplemented with either ECS, BSA or PVA. The first experiment investigated the influence of different medium-supplements (ECS, BSA or PVA) on nuclear maturation and revealed no significant differences among treatment groups nor between categories of COC (63.9% to 74.9% and 48.9% to 77.0%, respectively). The time course of in vitro fertilization was elucidated in Experiment 2 in medium supplemented with either protein or PVA during maturation and fertilization. Penetration was not affected (70.9% to 79.3% penetration 12 h after onset of oocyte-sperm-co-incubation), but formation of pronuclei was decreased (P < 0.05) 12 and 19 h after onset of oocyte-sperm-co-incubation and was retarded in medium supplemented with PVA (12 h: 63.8 vs 21.4 %; 19 h: 57.5 vs 20.8 %, respectively) while cleavage was not affected. In Experiment 3, six treatment groups were formed in which the two different morphological categories of cumulus-oocyte-complexes (COC) were incubated in basic medium supplemented with 1) ECS during maturation and embryo culture and BSA during fertilization; 2) PVA during maturation and embryo culture, fertilization medium with PVA; 3) PVA during maturation and embryo culture, fertilization medium with BSA; 4) BSA (1 mg/ml) during maturation, fertilization and embryo culture; 5) BSA (6 mg/ml) during maturation, fertilization and embryo culture; and 6) BSA (10 mg/ml) during maturation, fertilization and embryo culture. The rates of cleavage and the development to morulae or blastocysts did not differ (P > 0.05) among treatment groups and between both categories of COC and were showing a high degree of variability (cleavage 54.0% to 65.1% and 41.3% to 55.7%, respectively; morulae 25.3% to 53.0% and 26.0% to 51.2%, respectively; blastocysts 5.4% to 24.7% and 0.6% to 20.3%, respectively). Parthenogenetic activation only rarely occurred in medium containing PVA throughout all steps of in vitro production of bovine embryos (Experiment 4) and led to early cleavage stages (8%), but no development to morula- or blastocyst-stages was observed. It is concluded that 1) formation of pronuclei was retarded in medium lacking protein-supplementation, indicating that BSA is required for regular fertilization in vitro and 2) under our experimental conditions, protein-supplementation is not necessary for maturation and development up to the blastocyst stage in vitro.

Journal Article↗
PubMed1995

Eimeria maxima gametocyte antigens: potential use in a subunit maternal vaccine against coccidiosis in chickens.

Affinity-purified gametocyte antigens (APGA) from Eimeria maxima, emulsified in Freund's adjuvant, were injected intramuscularly into breeding hens on two or three occasions. As a result, progeny of the immunized hens were partially immune to infection with E. maxima, Eimeria tenella and Eimeria acervulina (with a reduction in total oocyst output of 45-63% as compared with progeny of untreated hens). Thus, APGA in Freund's adjuvant appears to have great potential as part of a maternally applied vaccine against coccidiosis. The ability of APGA to induce partial cross-species protection is most probably due to the existence of conserved epitopes in the different species as indicated by comparative Western blots of E. maxima and E. tenella. Surprisingly, Freund's adjuvant by itself also induced significant levels of maternal immunity to coccidiosis (with a 12-35% reduction in oocyst output in the progeny). In contrast to the purified antigens or Freund's alone, crude extracts from gametocytes as well as other developmental stages, induced little if any significant maternal immunity despite provoking the production of large amounts of parasite-specific IgG, including antibodies to APGA. This result indicates that a successful maternal vaccine against coccidiosis requires, in addition to good recognition of protective antigens, the exclusion of irrelevant antigens from the vaccine preparation.

Animals↗
PubMed1995

Cytokine and immunoglobulin subclass responses of rats to infection with Eimeria nieschulzi.

SIV rats infected with a high dose (50,000 oocysts) of Eimeria nieschulzi displayed clinical symptoms of coccidiosis such as diarrhoea (days 6 and 7 post-primary infection) and weight loss (days 6-8 post-primary infection) and were completely immune to challenge with a similar dose. The ability of rats to produce tumour necrosis factor (TNF) in vivo was enhanced during the period of oocyst excretion in the primary infection but significant production of TNF did not occur after challenge infection. Thus, TNF does not appear to be an important factor in resistance to infection with E. nieschulzi but may play some role in resistance to primary infection and in the pathology associated with E. nieschulzi infection. Parasite-specific serum IgM levels (measured by enzyme-linked immunosorbent assay) were also increased during primary infection but returned to background levels at the end of the patent period and were not affected by challenge infection. In contrast to TNF and IgM, serum concentrations of E. nieschulzi-specific IgG1, IgG2a, IgG2b, IgG2c and intestinal tissue levels of IgA did not begin to increase until after day 12 post-primary infection, reached peak levels between days 20 and 30 post-primary infection and were slightly increased by challenge infection.

Animals↗
PubMed1995

Specific IgG1 and IgG2 antibody responses of dogs to Leishmania infantum and other parasites.

Sera from dogs naturally infected with Leishmania infantum were analysed for the IgG subclass specificity of their antibody response by ELISA. Dogs infected with L. infantum produced both IgG1 and IgG2 antibodies with IgG2 being associated with asymptomatic infections and IgG1 being associated with disease (symptomatic dogs, non- or low-responsive to chemotherapy). The differential responses of IgG1 and IgG2 serum antibodies in asymptomatic and symptomatic dogs may indicate a dichotomous immune response to infection with L. infantum. To confirm this, on a broader scale, sera from dogs naturally exposed to an asymptomatic protozoan infection, Toxoplasma gondii, were also analysed as were sera from dogs exposed to the helminths, Dirofilaria immitis and Toxocara canis. Antibodies specific for T. gondii antigen detected in sera from 17 dogs were of the IgG2 subclass only. Both IgG1 and IgG2 antibodies to D. immitis and T. canis were present in the sera of naturally infected dogs but IgG1 appeared to be the predominant subclass. Furthermore, in dogs experimentally infected with T. canis, selective regulation of IgG2 and IgG1 responses was apparent since production of the two subclasses occurred at different times following infection, with IgG2 levels declining as IgG1 levels rose. Thus, the analysis of IgG subsets in parasitized dogs provides evidence of a dichotomous response to infection: IgG2 is associated with asymptomatic protozoan infections and IgG1 is associated with helminth infections and disease caused by protozoan infection.

Animals↗
PubMed1995

Endovascular techniques in adult aortic coarctation: the use of stents for native and recurrent coarctation repair.

PURPOSE: To report initial experiences with stent implantation in the treatment of native and recurrent aortic coarctation in adults. METHODS: Two adult patients were diagnosed with aortic coarctation: in one, the native aorta was involved, and in the other, the stenosis involved a prior coarctation repair. Both patients were offered and selected angioplasty with possible stent implantation as an alternative to surgery. RESULTS: In the patient with recurrent narrowing, thrombolysis and balloon dilation preceded the successful deployment of three Palmaz stents along the grafted segment. In the case of native disease, one Palmaz stent was implanted primarily at the site of a critical, focal stenosis. No complications were encountered, and recovery was uneventful. Follow-up at 12 and 6 months, respectively, showed sustained clinical improvement with resolution of symptoms and excellent hemodynamic values. CONCLUSIONS: The positive outcome in these early cases supports further evaluation of the efficacy of adjunctive or primary stenting for treatment of native or recurrent aortic coarctation in adults.

Aortic Coarctation↗
PubMed1995

Echinococcus multilocularis (Cestoda), the causative agent of alveolar echinococcosis in humans: first record in Poland.

Echinococcus multilocularis, the causative agent of human alveolar echinococcosis, was found for the first time in Poland in 2 of 20 red foxes (Vulpes vulpes), originating from the area of Gdansk (northern Poland). This finding supports the hypothesis that the endemic area of this parasite in central Europe (Belgium, France, Luxembourg, Switzerland, Liechtenstein, Germany, and Austria) is not an isolated focus as previously anticipated but is connected with the large endemic zone in Russia.

Animals↗
PubMed1995

[The status of infection with Toxoplasma gondii in the Swiss population: contribution of a seroepidemiologic study from the Zurich canton].

To obtain information on the seroprevalence of specific antibodies to Toxoplasma gondii at the level of the general population, a study was performed using 4300 serum samples: 3500 samples collected at the blood donor center of Zürich (individuals between 18 and > 65 years old), 500 serum samples from children referred to the University Children's Hospital of Zürich (between 1 month and 17 years old) and 300 maternal sera, collected at delivery (from a mother-child sera collection of the University Children's Hospital of Zürich). Samples were systematically collected by age- (5 years) and sex-groups (sex ratio 1:1), until the desired number was obtained. The crude seroprevalence of specific IgG anti-T. gondii was 52.4% (confidence interval at 95% [p < 0.05]: 50.9-53.9). There were no significant differences between males and females. The seroprevalence of the group of women of childbearing age (between 20 and 40) was 40%. The comparison of this value with the results obtained from 300 maternal sera from the mother-child collection revealed no significant difference between the two groups. On the basis of these results and assuming that the information obtained at the level of the general population in the region of Zürich is representative of Switzerland, it was possible to calculate the required sample size to initiate a national study on seroprevalence of the infection with T. gondii among women at time of delivery.

Adolescent↗
PubMed1994

Prophylaxis of bovine trichostrongylidosis in the alpine region: effect of pasture contamination on infections in calves receiving a morantel sustained-release trilaminate bolus in mid-July.

In the alpine region, mixed grazing systems with cattle of different age, origin and prophylaxis against trichostrongylid infections are most common. Under these conditions the administration of anthelmintic devices to susceptible calves is frequently postponed to June or July to achieve a better protection during the period of increased pasture infectivity in summer and autumn. In a field experiment with 27 first-year grazing calves a morantel sustained-release trilaminate bolus (MSRT, Pfizer) was given to two groups (Groups A and B) of nine naturally infected calves each, on 22 July. Calves of Group B were moved to a clean pasture (B) 1 day later, whereas the calves of Group A remained on the previous pasture (A) together with nine untreated calves (Group C). The contamination with infective larvae (L3) on Pasture A remained below 1000 L3 kg-1 dry matter, which was sufficient to produce clinical parasitic gastroenteritis in five of nine control calves. The MSRT bolus reduced the mean egg output by more than 90% within 14 days after administration and prevented clinical parasitic gastroenteritis in the calves of Groups A and B. Owing to the persisting infection risk on Pasture A, the mean serum pepsinogen levels reached about 3000 mU tyrosine in the calves of Group A in September compared with approximately 2000 mU in Group B grazing the clean pasture. However, the differences in pasture contamination were not reflected in the mean bodyweight of the calves, which were 20 kg heavier at the end of the trial in both MSRT-treated groups compared with the control calves (P < 0.01). As there is a high probability that a moderate larval contamination is present on prealpine and alpine community pastures in summer, the metaphylactic use of an MSRT bolus in mid-July is likely to limit trichostrongylid infections within a subclinical range and thus provides sufficient protection of susceptible calves against parasitic gastroenteritis.

Animals↗