ABSTRACT
OBJECTIVES: This study was carried out in order to evaluate the efficacy of the recently developed picobirnavirus (PBV) sets of primers and to establish the phylogenetic relationships of Argentine strains with PBV strains isolated in China and the USA. METHODS: Thirteen fecal specimens tested as positive for PBV by polyacrylamide gel electrophoresis were analyzed by reverse transcription-polymerase chain reaction assays using primers target to the genomic segments 2 of PBV strains isolated in China and the USA. The amplicons were sequenced and analyzed. RESULTS: Primers derived from the China strain produced amplicons in only 4 of the 13 specimens (30.76%). No sample was revealed as positive with the primers derived from the US strain. DNA sequencing of polymerase chain reaction products differed in nucleic acid and amino acid sequences by 13.9-42.28% and 18.1-51.1%, respectively. Despite this strain diversity, three domains of conserved nucleotide sequences as well as the amino acid motif D-S-D typical of RNA-dependent RNA polymerase gene of double-strand RNA viruses were identified. Comparatively, these conserved regions were also identified in homologous PBV strains from the USA and China. Phylogenetic analysis showed no time or geographic clustering. CONCLUSIONS: These findings provide evidence that PBV may represent an emerging heterogeneous group of viruses.
Subject(s)
Genome, Viral , Picobirnavirus/genetics , Adolescent , Adult , Amino Acid Sequence , Argentina , Base Sequence , China , DNA, Viral/genetics , Female , Genetic Variation , Humans , Male , Middle Aged , Molecular Sequence Data , Phylogeny , Picobirnavirus/classification , Picobirnavirus/isolation & purification , Picobirnavirus/pathogenicity , RNA Virus Infections/virology , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid , United StatesABSTRACT
El suero de 176 pacientes con antecedentes epidemiológicos o signos radiológicos y clínicos de hidatidosis fue sometido a contrainmunoelectroforesis (CIEF) e inmunoensayo enzimático (ELISA), utilizándose para ambas técnicas un antígeno semipurificado obtenido de los quistes de pacientes. Los resultados se compararon con los obtenidos por estudios radiológicos complementarios y se corroboraron mediante el examen de los quistes resecados. La biopsia confirmó el diagnóstico de hidatidosis en 65 (37%) pacientes y reveló la presencia de otras enfermedades en los 111 (63%) pacientes restantes. De los 176 pacientes estudiados, 36 (20,4%) tuvieron resultados positivos en la CIEF y 62 (35,2%) en el ELISA. Los resultados de ambas técnicas mostraron una excelente correlación con el diagnóstico posquirúrgico, ya que no hubo un solo resultado positivo falso y el ELISA produjo resultados negativos falsos en tres (4,6%) pacientes con quistes infectados, infértiles o con algún grado de calcificación. Por último se describe la estandarización de un microELISA fácil de usar y barato.
The sera of 176 patients with epidemiologic antecedents or radiologic and clinical signs of hydatidosis were tested by counterimmunoelectrophoresis (CIE) and enzyme-linked immunoassay (ELISA). A semipurified antigen from cysts of human origin was used for both techniques. The results were compared with those obtained from complementary radiologic studies and were confirmed by examination of excised cysts. Biopsy confirmed the diagnosis of hydatidosis in 65 patients (37%) and revealed the presence of other diseases in the remaining 111 (63%). Of the original 176 patients, 36 (20.4%) were positive by CIE and 62 (35.2%) by ELISA. Both techniques showed an excellent correlation with postsurgical diagnosis; neither produced any false positives, and the ELISA gave false negative results for only three patients (4.6%) with cysts that were infected, infertile, or calcified to some degree. The paper describes standardization of an inexpensive and easy-to-use microELISA.
