ABSTRACT
Se comparó en cobayos la seguridad, inmunogenicidad y eficácia protectora de um lote de vacuna Candid #1 (C#1) fabricada en Estados Unidos de América (EE.UU.) y distintos lotes de la misma vacuna fabricados en Argentina (Arg.). El lote TSI 5-1-92 (EE.UU) y los lotes Exp N3, 7A y 8A (Arg) fueron inoculados (0.5ml, IM) en cobayos de 250400g. Para cada ensayo diez animales recibieron solución fisiológica y sirvieron como control. Todos fueron desafiados con la cepa patógena P23790 de vírus Junin. Se registro: a) temperatura rectal, b) peso corporal , c) presencia de anticuerpos neutralizantes (AcNT) pré y post-vacunación, d) respuesta al desafio . Todos los animales vacunados desarrollaron AcNT anti vírus Junin (rango= 4081920 y sobrevivieron al desafio. En cada grupo control 810 animales murieron (dia 23.3+_ 5.4 post- desaportada y los diferentes lotes de C#1 producidos en Argentina.
Subject(s)
Guinea Pigs , Animals , Hemorrhagic Fever, American/drug therapy , Junin virus/drug effects , Vaccines, Attenuated/therapeutic use , Viral Vaccines/therapeutic use , Argentina , Case-Control Studies , Chlorocebus aethiops , Confidence Intervals , Disease Models, Animal , Drug Evaluation, Preclinical , Hemorrhagic Fever, American/immunology , Junin virus/immunology , Vero Cells , Vaccines, Attenuated/immunology , Viral Vaccines/immunologyABSTRACT
O artigo não apresenta resumo.
ABSTRACT
The condition factor for nine species of tropical freshwater fish of the Characidae family in the upper Paraná River floodplain is described. Fish were caught over a period of 12 months (February 1993 to March 1994). Knowledge of the nine species is important for adequate management and maintenance of the biological equilibrium of the ecosystem
Subject(s)
Animals , Fishes , Brazil , Environment , Fishes , Fresh Water , Population Dynamics , Seasons , Species SpecificityABSTRACT
The condition factor for nine species of tropical freshwater fish of the Characidae family in the upper Paraná River floodplain is described. Fish were caught over a period of 12 months (February 1993 to March 1994). Knowledge of the nine species is important for adequate management and maintenance of the biological equilibrium of the ecosystem.
O fator de condição foi descrito para 9 espécies de peixes da família Characidae de água doce tropical na planície de inundação do alto rio Paraná. Os peixes foram capturados em um período de 12 meses (de fevereiro de 1993 a março de 1994). O conhecimento dessas nove espécies é extremamente importante para a obtenção de um adequado manejo e manutenção do equilíbrio biológico do ecossistema.
ABSTRACT
The active coexistence of two pathogenic arenaviruses, Junin (JUNV) and lymphocytic choriomeningitis (LCMV), in the same region of Argentina, has been known since the early 70s, and records of clinical and subclinical human infections by one and/or the other agent have been continuously produced for the last 25 years. Anti-LCMV antibody is currently searched only by indirect immunofluorescence, a test that shows cross reactions among a number of arenaviruses yielding, in the cases of LCMV and JUNV consecutive infections, a concomitant seroconversion for both viruses, as an inconclusive diagnostic result. In contrast, neutralization (NT) tests reveal arenavirus antibodies directed to unique epitopes on these virus envelopes, thus allowing to disclose the sequence in the cases of consecutive infections. In this paper, the characteristics of neutralization (NT) test for LCMV in cell cultures are described, as well as its performance in the field diagnosis of LCMV human infections. The native LCMV strain Cba An 13065 was inoculated on L-929 cell (ATCC CCL 1), and procedures were followed to perform a constant virus-variable serum NT test. Final points of sera titrations were expressed as the maximal serum dilution that yielded 75
of pfu inhibition. This NT test was assayed on paired serum samples of 36 patients with confirmed Argentine hemorrhagic fever (AHF) (a disease caused by JUNV), who had had a known previous contact with LCMV through IFI. The use of this one test led to confusing diagnosis of the disease due to concomitant seroconversion for JUNV and LCMV. By using NT test, it was shown that: some of them were possibly not infected by LCMV, and that 30/36 cases (83.3
) had a pre-existing level of LCMV antibody, with titers in the range of 5 to 640, remaining unchanged 60 days after the clinical AHF. This shows that NT antibodies to LCMV are not influenced by the outcome of the immune response to JUNV, thus confirming the efficiency of NT test as identificator among arenaviruses. To assess the performance of this NT test in individuals having only IFI antibodies to LCMV, 126 serum samples obtained through serological surveillance in a rural area of Argentina, were used. It was found that NT had improved coincidence with IFI as IFI titers increased. Interpretations were based on the pan-arenavirus antibody response obtained by using IFI as the only test. Results presented herein prove that the described NT test is a valuable tool for the detection of LCMV infections, particularly when a previous infection with LCMV has to be demonstrated during the acute phase of Argentine hemorrhagic fever.