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B Gottstein

Publications and source records attributed to B Gottstein.

187 records · Page 11Linked to original sources

An enzyme-linked immunosorbent assay for diagnostic detection of Taenia saginata copro-antigens in humans.

An immunodiagnostic sandwich enzyme-linked immunosorbent assay (ELISA) was developed for the detection of soluble Taenia saginata antigens in stool samples (copro-antigens) of infected humans, using affinity-purified polyclonal antibodies obtained from rabbits hyperimmunized with excretory/secretory antigens derived from T. saginata maintained in vitro. Investigation of operating characteristics showed very low cross-reactivity with crude antigens from helminths other than Taenia, including Dipylidium caninum and Diphyllobothrium latum. The specificity of the assay was 95% when testing stool samples from 100 persons who were either infected with Ascaris lumbricoides, Trichuris trichiura, hookworms, Enterobius vermicularis or Hymenolepis nana, or who had no intestinal helminthosis detected. Analysis of diagnostic sensitivity demonstrated that in 85% of 34 samples from 23 untreated persons with intestinal T. saginata infection (selected by previous proglottid and/or egg detection) copro-antigens were detected by the T. saginata ELISA. In the same samples, Taenia eggs were detected in 62%. Only 41% of the samples reacted positively in a heterologous T. hydatigena ELISA. Post-treatment control revealed a high concentration of T. saginata copro-antigens for 1-4 d after administration of niclosamide or praziquantel, and negative values 9-17 d after treatment. The Taenia copro-antigens remained detectable by ELISA even after storage of untreated faeces at 25 degrees C for at least 5 d.

Animals↗

Cytologic diagnosis of isolated pancreatic alveolar hydatid disease with immunologic and PCR analyses. A case report.

BACKGROUND: Alveolar hydatid disease (AHD) is a rare and severe parasitic infection caused by the larval stage of the fox tapeworm, Echinococcus multilocularis. AHD mainly involves the liver, and although it may extend progressively to the pancreas, isolated pancreatic localization has not been reported previously. CASE: A 68-year-old white female presented with a multicystic mass in the pancreas. Fine needle aspiration showed some protoscolices, free hooklets and fragments of laminated layer, which are pathognomonic features of echinococcosis. Serologic analyses by an enzyme-linked immunosorbent assay using Em2plus antigen showed high antibody reactivity of the patient's serum, which is indicative of an infection with E multilocularis. Diagnosis was finally confirmed by molecular and immunologic analyses of the cytologic material by polymerase chain reaction and direct immunofluorescence. CONCLUSION: This case illustrates the value of cytology in the identification of echinococcosis, particularly when it involves extrahepatic sites, where the risk of misdiagnosis may be related to its extremely rare occurrence. Precise parasitologic tying of E multilocularis in endemic areas is important.

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Selection, recombination and history in a parasitic flatworm (Echinococcus) inferred from nucleotide sequences.

Three species of flatworms from the genus Echinococcus (E. granulosus, E. multilocularis and E. vogeli) and four strains of E. granulosus (cattle, horse, pig and sheep strains) were analysed by the PCR-SSCP method followed by sequencing, using as targets two non-coding and two coding (one nuclear and one mitochondrial) genomic regions. The sequencing data was used to evaluate hypothesis about the parasite breeding system and the causes of genetic diversification. The calculated recombination parameters suggested that cross-fertilisation was rare in the history of the group. However, the relative rates of substitution in the coding sequences showed that positive selection (instead of purifying selection) drove the evolution of an elastase and neutrophil chemotaxis inhibitor gene (AgB/1). The phylogenetic analyses revealed several ambiguities, indicating that the taxonomic status of the E. granulosus horse strain should be revised.

Animals↗

Is high prevalence of Echinococcus multilocularis in wild and domestic animals associated with disease incidence in humans?

We investigated a focus of highly endemic Echinococcus multilocularis infection to assess persistence of high endemicity in rural rodents, explore potential for parasite transmission to domestic carnivores, and assess (serologically) putative exposure versus infection frequency in inhabitants of the region. From spring 1993 to spring 1998, the prevalence of E. multilocularis in rodents was 9% to 39% for Arvicola terrestris and 10% to 21% for Microtus arvalis. From June 1996 to October 1997, 6 (7%) of 86 feral dogs and 1 of 33 cats living close to the region tested positive for intestinal E. multilocularis infection. Testing included egg detection by coproscopy, antigen detection by enzyme-linked immunosorbent assay (ELISA), and specific parasite DNA amplification by polymerase chain reaction. Thus, the presence of infected domestic carnivores can increase E. multilocularis exposure risk in humans. A seroepidemiologic survey of 2,943 blood donors in the area used specific Em2-ELISA. Comparative statistical analyses of seroprevalence and clinical incidence showed an increase in Em2-seroprevalence from 1986 and 1996-97 but no increase in clinical incidence of alveolar hydatid disease.

Animals↗

Application of random amplified polymorphic DNA (RAPD) assay to the study of mites related to allergic diseases.

In this study, the conditions for the successful application of the random amplified polymorphic DNA (RAPD) assay to differentiate mite populations based on genetic variation were defined. Five species of mites related to allergic diseases were studied: Dermatophagoides pteronyssinus, D. farinae (2 strains), Blomia tropical is, Glycyphagus domesticus and Tyrophagus putrescentiae. The mites were isolated from pure cultures and processed according to the method described in this paper. The banding patterns obtained were different for all the species studied. When the DNA from two different strains of D. farinae were studied, the "fingerprint" banding patterns obtained showed differences between them. The random amplified polymorphic DNA assay may be a useful tool to aid the taxonomic study of mite populations.

Animals↗