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[Serial observations of a pulmonary echinococcus, with rupture into the bronchial system (author's transl)].

The radiological course of an echinococcus cyst of the lung before and after rupture is described, together with the cytological and histological findings. The resultant tissue changes and appropriate treatment (lobectomy) are discussed. In the presence of the appropriate radiological changes, eosinophil granulocytes in the sputum suggest cyst rupture, even in the absence of echinococcus tissue. However, bronchial asthma or Löffler's infiltrates should be excluded clinically. They delayed appearance of peripheral blood eosinophilia after cyst rupture and the development of an eosinophilic broncho-pneumonia is noteworthy.

Adult

Detection of the Echinococcus granulosus diagnostic arc 5 in sera from patients with surgically-confirmed E. multilocularis infection.

The Echinococcus granulosus diagnostic arc 5 was revealed by sera from an Alaskan and a Swiss patient with surgically confirmed E. multilocularis infections. The possibility of each patient harboring a concurrent infection with both parasites may be disregarded on the basis of radiologic, scintillographic and surgical data. This conclusion is compatible with ecologic and epidemiologic considerations. These observations suggest that the immunoelectrophoresis test based on arc 5 positivity is not E. granulosus-specific as originally described.

Adult

Humoral response to sheep red blood cells in C57L/J mice during early and chronic stages of infection with Echinococcus multilocularis cysts.

C57L/J male mice infected with Echinococcus multilocularis cysts were challenged intraperitoneally at 4, 8, and 12 weeks postinfection (p.i.) with 3 x 10(9) sheep erythrocytes. The direct plaque forming cells, 2-mercaptoethanol (2-ME) sensitive (4-day sera) and 2-ME-resistant (8-day sera) haemagglutinin responses were significantly elevated at eight and 12 weeks p.i. as compared to controls or the fourweeks postinfected mice. Possible mechanisms of immunopotentiation in the chronically infected mice is discussed in relation to the larval cyst mass, splenomegaly, and B cell hyperplasia in the lymphoid tissues during the course of infection.

Animals

Partial purification and properties of ovine liver Echinococcus granulosus protoscolices phospholgucose isomerase.

Echinococcus granulosus protoscolex is the actual larval stage of the cestode causing echinococcosis both in man and animals. In the present report, certain properties of phosphoglucose isomerase from the ovine liver E. granulosus protoscolices have been studied and compared with those of the hydatid cyst fluid and the healthy ovine liver enzymes. The protoscolices enzyme prepared in a manner similar to the hydatid cyst fluid and the ovine liver enzymes exhibited the following properties: (1) pH optimum of 8.2 (2) KM value of 0.23 mM, (3) the enzyme was inhibited in the presence of high concentrations of alpha-D-glucose 6-phosphate, (4) no detectable inhibition of the enzyme was observed in the presence of phosphate ion up to 4.1 mM, (5) the protoscolices enzyme was less thermostable as compared to the hydatid cyst fluid and the ovine liver enzymes, (6) the protoscolices enzyme had a lower Ki value (0.7 mM) as compared to either the hydatid cyst fluid (1.1 mM) or the ovine liver enzymes (4.6 mM) when 6-phosphogluconic acid was used as a competitive inhibitor.

Animals

Strain differences in Echinococcus granulosus, with special reference to the status of equine hydatidosis in the United Kingdom.

The genetics of speciation in the genus Echinococcus are briefly discussed. As the organism is a hermaphrodite and multiplies asexually in the larval stage, the genetic mechanism for the ready production of new strains is inherent in the life-cycle. Some biological, biochemical and nutritional differences between the horse and sheep strains are examined. The sheep strain may be grown to sexual maturity, in vitro, in a diphasic system; the horse strain fails to grow in such a system. Differences have also been demonstrated between the soluble proteins of the two strains. The sheep strain is infective to man but, probably, non-infective to horses. The horse strain (which is now the major strain in the U.K and Ireland) appears to be poorly infective to sheep and may prove to be non-infective to man. The importance of determining the basic characteristics of other strains of E. granulosus are also stressed.

Animals

Detection of antibodies against Echinococcus granulosus arc 5 antigens by double diffusion test.

This report deals with an evaluation of a double diffusion (DD5) test which employs a control antiserum against Echinococcus granulosus arc 5 antigens to recognize arc 5-positive sera by a reaction of identity. The DD5 test was more sensitive than the immuno-electrophoresis (IEP5) test based on the same positivity criterion and was equally specific for the immunodiagnosis of human hydatidosis. Its greater simplicity suggest its application as a substitute for the IEP5 test in diagnosis, particularly areas. The application of both DD5 and latex agglutination tests is recommended for hydatid immunodiagnosis on the basis of the present findings.

Antibodies

Studies on the mechanism of lysis of Echinococcus granulosus protoscoleces incubated in normal serum.

Brood capsules were obtained from freshly collected cysts of equine and ovine strains of Echinococcus granulosus. Protoscoleces were freed from brood capsules either by mechanical disruption or pepsin-HCI digestion. Preparations of protoscoleces studied included: mechanically released protoscoleces without further treatment, or incubated either in HCI pH 2.0 or in evaginating solution (containing Na taurocholate) for 24 h; pepsin-HCI released protoscoleces without further treatment or incubated in evaginating solution for 24 h or 7 days. Half of each preparation of ovine protoscoleces was fixed in absolute methanol. All fresh preparations of protoscoleces lysed rapidly when incubated in normal human serum. Studies with a fluorescein isothiocyanate (FITC) labelled sheep anti-human C3 antiserum revealed the presence of C3 on the surface of lysing protoscoleces. Antibody could not be detected on the surface of any of the preparations of fresh or methanol-fixed protoscoleces using direct or indirect fluorescent antibody tests suggesting that the classical pathway of complement activation was not involved in the lytic process. Strong evidence for lysis by the alternate pathway of complement activation was the lysis of protoscoleces which had been treated with pepsin-HCI and lysis of protoscoleces in guinea-pig serum deficient in C4 component of complement.

Animals

Ultrastructural immunocytochemical localization of two hydatid fluid antigens (antigen 5 and antigen B) in the brood capsules and protoscoleces of ovine and equine Echinococcus granulosus and E. multilocularis.

The unlabelled antibody method was used in the ultrastructural localization of two hydatid fluid antigens, antigen 5 and antigen B, in brood capsules and protoscoleces of Echinococcus granulosus and E. multilocularis. Antigen 5 was found in the parenchyma cells of the protoscolex and brood capsule wall and to a lesser extent in the walls of the flame cells and collecting ducts of the excretory system and in the surrounding interstitial material. It is suggested that, while some excretion of this antigen may occur from the protoscolex, it could also be liberated into the cystic cavity by degeneration of protoscoleces and parenchymal cells of the brood capsule wall. Antigen B was found mainly in the distal cytoplasm and perinuclear cytoplasm of the tegument anterior to the suckers. It is apparently secreted to the outside and was present in the brood capsule contents; it adheres to the anterior surface and the posterior periodic acid-Schiff (PAS)-positive glycocalyx of the protoscolex and to the inner surface of the brood capsule wall. The protoscolex tegument posterior to the suckers was negative. The parenchyma cells of the protoscolex and brood capsule wall were also positive although the intensity of the reaction product was variable.

Animals

[Echinococcus multilocularis causing extensive biliary obstruction (author's transl)].

Infection of man by Echinococcus multilocularis occurs relatively seldom, most commonly localizing in the liver in the manner of a malignant tumour. A case of alveolar hydatid disease is reported presenting with extensive biliary obstruction, and a large cavitation in the liver due to necrosis. A review of epidemiology, clinical and roentgenological findings is given.

Celiac Artery

Protection of cotton rats against experimental Echinococcus multilocularis infections with BCG cell walls.

Previous works has indicated that cotton rats treated with Mycobacterium bovis strain BCG are effectively protected against an infection with the metastatically proliferating metacestodes of Echinococcus multilocularis. In an attempt to induce a similar protection in the absence of tubercular granulomatous lesions, cotton rats were treated with BCG cell walls. A single injection of 150 micrograms of cell walls, emulsified in mineral oil-Tween-saline, 2 weeks before the inoculation of the parasite completely protected the animals against infection with E. multilocularis. This protection was correlated with an increase in the numbers of monocytes and, as judged by acid phosphatase activity, an activation of these cells. This study shows that BCG cell walls are as effective in protecting animals against E. multilocularis as the viable organism.

Animals

Permeability studies on taenid metacestodes: I. Uptake of proteins by larval stages of Taenia taeniaeformis, T. crassiceps, and Echinococcus granulosus.

Host immunoglobulins of several different classes were detected within the bladder fluids of Taenia taeniaeformis, T. crassiceps, and Echinococcus granulosus. Radioiodinated proteins were taken up in vitro by larvae of both T. taeniaeformis and T. crassiceps and were shown to retain their physicochemical and antigenic characteristics. Rates of uptake were similar in the 2 species and were not related to the molecular weight of the proteins. Immunoglobulins were taken up both in vitro and in vivo by larvae of T. taeniaeformis. Absorbed immunoglobulins were shown to retain both antigen binding capacity and biologic functions associated with the Fc portion of the molecules. Not all cysts of E. granulosus contained detectable host proteins. Uptake of 125I occurred when hydatid cysts were exposed to labeled proteins in vitro, but it appeared that rapid degradation of the labeled carrier led to the appearance of dialysable fragments. This may be attributable to proteolysis within the bladder fluid. We conclude that taeniid metacestodes are capable of absorbing a variety of proteins, and that these macromolecules can retain their structural and functional integrity following transport. This absorptive capacity accounts for the presence of host serum components within bladder fluids.

Animals

Further observations on the specificity of antigen 5 of Echinococcus granulosus.

The presence of IgE antibodies to antigen 5 of Echinococcus granulosus was detected by means of radioimmunoelectrophoresis in the sera of two of six patients infected with E. multilocularis. Sera from three of these patients gave a precipitin band in gel diffusion tests identical to that produced by a monospecific rabbit anti-E. granulosus antigen 5 serum, when tested against whole hydatid fluid. Sera from 19 individuals infected with Fasciola hepatica, 20 with Schistosoma mansoni, and 5 with with Taenia saginata showed no detectable antibodies against antigen 5 of E. granulosus, The monospecific rabbit anti-E. granulosus antigen 5 serum did not react in immunodiffusion with homologous antigen when absorbed with either 4 mg/ml of whole hydatid fluid or with 200 mg/ml of a soluble E. multilocularis extract. Absorption of the monospecific antiserum with crude antigens of either F. hepatica, Onchocerca volvulus, S. mansoni, or T. saginata did not abolish the reaction with antigen 5. It appears, therefore, that antigen 5 can no longer be considered specific for E. granulosus, but is also present in E. multilocularis. In the light of this observation, some reevaluation of immunodiagnostic tests in hydatid disease will be necessary.

Antibody Formation

Antigenic characterization of Echinococcus granulosus cysts.

Limited numbers of antigens were detected in the structural components of Echinococcus granulosus cysts by double diffusion and immunoelectrophoresis tests using homologous and heterologous antisera without antibody activity to host serum contaminants. Although antigens common to the germinal membranes, laminated layers and protoscoleces were demonstrated, no evidence was found of antigen sharing between the laminated layer and hydatid fluid from fertile and sterile cysts. These fluids, however, had antigenic determinants in common with protoscoleces. Antigens responsible for the formation of a characteristic cathodic are were detected but only in the three structural cyst components. In contrast, E. granulosus arc 5 antigens were found solely in hydatid fluid. These observations suggest that these two antigen groups are of somatic and metabolic origin, respectively. The results are discussed in terms of current knowledge of the immunobiology of hydatid cysts.

Animals

Comparative antigenic characterisation of Echinococcus granulosus and Taenia hydatigena cyst fluids by immunoelectrophoresis.

Hydatid cyst fluid from Echinococcus granulosus (HCF) and cyst fluid from Taenia hydatigena (TCF) cysts were compared in reciprocal immunoelectrophoresis (IEP) tests using homologous and heterologous antisera which were free of antibodies to host serum contaminants. The antigens for the E granulosus arc 5 were demonstrated in TCF. Antibody activity to these and other antigens common to HCF and TCF was removed from homologous antisera by absorptions with the heterologous antigenic preparation. Antigens not shared by the two metacestodes fluids were then demonstrated by IEP tests. These findings are discussed in terms of their significance to phylogenetic and immunodiagnostic studies of these parasites in their immediate hosts.

Animals

Epidemiological analysis of factors influencing rate of progress in Echinococcus granulosus control in New Zealand.

The factors influencing the rate of progress in Echinococcus granulosus control in New Zealand were analysed by hydatid control area using stepwise multiple regression techniques. The results indicated that the rate of progress was related positively to initial E. granulosus prevalence in dogs and the efficiency with which local authorities implemented national control policy, and negatively to the Maori proportion in the local population and the number of dogs per owner. Problems in analysis of the New Zealand data are discussed and improved methods of monitoring progress in hydatid disease control programmes are described.

Animals

[Kinetics of the serological response in the experimental primary hydatid disease of mice infected with Echinococcus granulosus embryophores (author's transl)].

A serological response kinetics study was carried out in CF-1 mice orally infected with Echinococcus granulosus embryophores using immuno-electrophoresis, double diffusion, latex agglutination and passive hemagglutination. Starting from the 76th day after the infection, serum antibodies reach the minimum detectable level by immunoelectrophoresis test. Band number 5, now considered as specific for E. granulosus, was proved to be the first precipitating system exhibited in this test. Double diffusion, latex agglutination and passive hemagglutination tests developed positive results later (125--144 days after infection). Correlation between serologic and anatomo-pathologic findings suggest that hydatid cyst fluid presence in the cysts is necessary for circulating antibodies production.

Animals