RESUMEN

The aim of this study was to determine the feasibility of combining water quality analysis with different biomarkers to characterise the relationship between anthropogenic contamination and biotic response in the Sinos River, southern Brazil. Wistar rats were studied using three biomarkers combined with physical, chemical and microbiological analysis to assess the effects of pollution at four sampling sites. The induction of oxidative stress was quantified by MDA levels in peripheral blood, lymphocyte DNA damage was determined using the comet assay, and histopathological changes were analysed in the liver. After sampling, animals were allowed to drink the river water during a 48 hours period. No increase in oxidative stress and DNA damage was observed. However, liver damage was observed in the animals exposed to water samples, indicating that the Sinos River is contaminated with hepatotoxic substances. Water analyses confirmed that water quality decreased downriver.

O objetivo deste estudo foi determinar a viabilidade de combinar a análise da qualidade da água com o estudo de biomarcadores para caracterizar a relação entre contaminação antropogênica e resposta biótica no rio dos Sinos, sul do Brasil. Ratos Wistar machos foram estudados usando três biomarcadores combinados com análises físicas, químicas e microbiológicas para determinar os efeitos da poluição em quatro locais de amostragem de água. A indução do estresse oxidativo foi quantificada pelos níveis de MDA no sangue periférico, o dano do DNA linfocitário foi determinado usando o ensaio cometa, e as alterações histopatológicas foram analisadas no fígado. As amostras da água do rio dos Sinos (dos quatro pontos selecionados) foram administradas por via oral (como água para beber) por 48 horas. Nenhum aumento do estresse oxidativo ou do dano do DNA foi observado. Entretanto, dano do tecido hepático foi verificado nos animais expostos à ingestão das amostras da água, indicando que o rio dos Sinos está contaminado com substâncias hepatotóxicas. As análises das amostras de água confirmaram a redução da qualidade da água em direção à foz do rio.

Asunto(s)

RESUMEN

The aim of this study was to determine the feasibility of combining water quality analysis with different biomarkers to characterise the relationship between anthropogenic contamination and biotic response in the Sinos River, southern Brazil. Wistar rats were studied using three biomarkers combined with physical, chemical and microbiological analysis to assess the effects of pollution at four sampling sites. The induction of oxidative stress was quantified by MDA levels in peripheral blood, lymphocyte DNA damage was determined using the comet assay, and histopathological changes were analysed in the liver. After sampling, animals were allowed to drink the river water during a 48 hours period. No increase in oxidative stress and DNA damage was observed. However, liver damage was observed in the animals exposed to water samples, indicating that the Sinos River is contaminated with hepatotoxic substances. Water analyses confirmed that water quality decreased downriver.

O objetivo deste estudo foi determinar a viabilidade de combinar a análise da qualidade da água com o estudo de biomarcadores para caracterizar a relação entre contaminação antropogênica e resposta biótica no rio dos Sinos, sul do Brasil. Ratos Wistar machos foram estudados usando três biomarcadores combinados com análises físicas, químicas e microbiológicas para determinar os efeitos da poluição em quatro locais de amostragem de água. A indução do estresse oxidativo foi quantificada pelos níveis de MDA no sangue periférico, o dano do DNA linfocitário foi determinado usando o ensaio cometa, e as alterações histopatológicas foram analisadas no fígado. As amostras da água do rio dos Sinos (dos quatro pontos selecionados) foram administradas por via oral (como água para beber) por 48 horas. Nenhum aumento do estresse oxidativo ou do dano do DNA foi observado. Entretanto, dano do tecido hepático foi verificado nos animais expostos à ingestão das amostras da água, indicando que o rio dos Sinos está contaminado com substâncias hepatotóxicas. As análises das amostras de água confirmaram a redução da qualidade da água em direção à foz do rio.

RESUMEN

The aim of this study was to determine the feasibility of combining water quality analysis with different biomarkers to characterise the relationship between anthropogenic contamination and biotic response in the Sinos River, southern Brazil. Wistar rats were studied using three biomarkers combined with physical, chemical and microbiological analysis to assess the effects of pollution at four sampling sites. The induction of oxidative stress was quantified by MDA levels in peripheral blood, lymphocyte DNA damage was determined using the comet assay, and histopathological changes were analysed in the liver. After sampling, animals were allowed to drink the river water during a 48 hours period. No increase in oxidative stress and DNA damage was observed. However, liver damage was observed in the animals exposed to water samples, indicating that the Sinos River is contaminated with hepatotoxic substances. Water analyses confirmed that water quality decreased downriver.

Asunto(s)

RESUMEN

The aim of this study was to determine the feasibility of combining water quality analysis with different biomarkers to characterise the relationship between anthropogenic contamination and biotic response in the Sinos River, southern Brazil. Wistar rats were studied using three biomarkers combined with physical, chemical and microbiological analysis to assess the effects of pollution at four sampling sites. The induction of oxidative stress was quantified by MDA levels in peripheral blood, lymphocyte DNA damage was determined using the comet assay, and histopathological changes were analysed in the liver. After sampling, animals were allowed to drink the river water during a 48 hours period. No increase in oxidative stress and DNA damage was observed. However, liver damage was observed in the animals exposed to water samples, indicating that the Sinos River is contaminated with hepatotoxic substances. Water analyses confirmed that water quality decreased downriver.

O objetivo deste estudo foi determinar a viabilidade de combinar a análise da qualidade da água com o estudo de biomarcadores para caracterizar a relação entre contaminação antropogênica e resposta biótica no rio dos Sinos, sul do Brasil. Ratos Wistar machos foram estudados usando três biomarcadores combinados com análises físicas, químicas e microbiológicas para determinar os efeitos da poluição em quatro locais de amostragem de água. A indução do estresse oxidativo foi quantificada pelos níveis de MDA no sangue periférico, o dano do DNA linfocitário foi determinado usando o ensaio cometa, e as alterações histopatológicas foram analisadas no fígado. As amostras da água do rio dos Sinos (dos quatro pontos selecionados) foram administradas por via oral (como água para beber) por 48 horas. Nenhum aumento do estresse oxidativo ou do dano do DNA foi observado. Entretanto, dano do tecido hepático foi verificado nos animais expostos à ingestão das amostras da água, indicando que o rio dos Sinos está contaminado com substâncias hepatotóxicas. As análises das amostras de água confirmaram a redução da qualidade da água em direção à foz do rio.

RESUMEN

The effects of diets with variable zinc levels on the midgut epithelial cells were studied in Oreochromis niloticus L. One hundred and twenty fry of tilapia were apportioned into 4 experimental groups (I, II, III and IV groups), with 30 fish in each treatment, 5 replicate aquaria per treatment containing 6 fish each. The animals of the 4 groups were fed with isonitrogenous (30% crude protein) and isoenergetic (3000 Kcal/Kg of digestible energy) diets with increasing quantities of zinc (44.59; 149.17; 309.93; 599.67 mg Zn/kg of diet), twice a day, for 93 days. Three fish from each group were sacrificed at 36, 66 and 93 days and samples of midgut were removed for ultrastructural analysis. After 93 days of treatment, 3 animals of each experimental group were used for the analysis of zinc concentration by atomic absorption spectrophotometry. The comparative relative index (CRI) revealed that the animals in groups II, III and IV contained, respectively, 1.99%, 34.67% and 22.78% more zinc than the mean concentration in animals from group I. The ultrastructural analysis showed enterocytes with swelling of smooth surfaced endoplasmic reticulum and dilated mitochondria with variable matrix rarefaction and cristae number reduction in the fish exposed to 599.67 mg Zn/Kg of diet at 66 and 93 days of treatment.

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RESUMEN

Annona squamosa Linn., family Annonaceae, is said to show varied medicinal effects, including insecticide, antiovulatory and abortifacient. The purpose of present study was to investigate if A. squamosa seed aqueous extract, in doses higher than that popularly used to provoke abortion, interferes with reproductive performance, and to correlate the ingestion of this extract with possible alterations in rat embryonic implantation. Doses of 300 mg/kg (Treated Group I, n = 17) and 600 mg/kg (Treated Group II, n = 12) body wt. were administered by gavage, during days 1 to 5 of pregnancy (preimplantation period). The control group (n = 13) received water in the same manner, during the same period for comparison with experimental groups. The animals were euthanized on day 10 of pregnancy. Treatment of dams during the preimplantation period showed no signs of toxicity, and no alteration in the corpora lutea, implantations and embryo in terms of development numbers. The percentage of preimplantation and postimplantation losses in treated groups I and II did not differ from those of control. Treatment with aqueous extract of A. squamosa seeds caused no morphological change in the endometrium. The absence of morphological alterations in uterine epithelial cells in treated groups I and II permitted a viable embryonic implantation, as verified by the number of embryos in development at day 10 of pregnancy. Thus, A. squamosa seed aqueous extract did not interfere with the reproductive performance of pregnant rats.

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RESUMEN

En este trabajo analizamos las características histoquímicas de los segmentos mandibular y maxilar del músculo aductor de la mandíbula en la carga. Las fibras musculares fueron clasificadas en tres tipos, de acuerdo con las distintas reacciones de las enzimas mATPasa (con pre-incubación ácida y alcalina) y NADH-TR. En la zona profunda fueron observadas solamente fibres rojas con metabolismo oxidativo. La zona superficial presentó fibras blancas con metabolismo glicólico. En las zonas de transición y profunda, fueron observadas fibras rojas, pequeñas, con metabolismo intermediario, dispuestas alredededor de fibras más grandes. Las fibras rojas fueron predominantes en el músculo A1 y las blancas en el A1a, ambos pertenecientes al segmento maxilar. En el segmento mandibular, el músculo A2 presentó numerosas fibras blancas dispuestas alrededor de muy pocas fibras rojas, las cuales predominaron en el músculo A3

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RESUMEN

The behaviour of cell cultures from 11 to 18 days-old Swiss albino mouse embryo infected with Pixuna virus was studied. Eleven day-old embryo cultures showed to be a permissive system supporting a productive and cytocidal infection. In contrast, the 13 to 18 day-old embryo cultures were also permissive and productive but no evidence of cytopathic effect was observed. D-glucosamine did not affect the infectivity titer of the Pixuna virus when 11 day-old embryo cultures were used. In these cultures the eclipse phase was observed between 15 and 90 min post-absorption (Figure 1).

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RESUMEN

Se estudio el comportamiento de cultivos de embrion de raton albino suizo, entre 11 y 18 dias de gestacion. infectados con el virus Pixuna. El cultivo de embrion de 11 dias resulto permisivo, dando una infeccion productiva y citocidica; el de 12 dias no mostro un efecto citopatico claro, y entre los 13 y los 18 dias, los cultivos resultaron ser permisivos, con una infeccion produtiva pero no citocidica. Se encontro que la fase de eclipse para el virus Pixuna en cultivo de embriones de 11 dias, estuvo entre los 15 y 90 min posteriores a la hora de adsorcion. La D-glucosamina no afecto el titulo infectivo del virus, usando embriones de 11 dias de edad como cultivo

Asunto(s)

RESUMEN

The behaviour of cell cultures from 11 to 18 days-old Swiss albino mouse embryo infected with Pixuna virus was studied. Eleven day-old embryo cultures showed to be a permissive system supporting a productive and cytocidal infection. In contrast, the 13 to 18 day-old embryo cultures were also permissive and productive but no evidence of cytopathic effect was observed. D-glucosamine did not affect the infectivity titer of the Pixuna virus when 11 day-old embryo cultures were used. In these cultures the eclipse phase was observed between 15 and 90 min post-absorption (Figure 1).

RESUMEN

Se estudio el comportamiento de cultivos de embrion de raton albino suizo, entre 11 y 18 dias de gestacion. infectados con el virus Pixuna. El cultivo de embrion de 11 dias resulto permisivo, dando una infeccion productiva y citocidica; el de 12 dias no mostro un efecto citopatico claro, y entre los 13 y los 18 dias, los cultivos resultaron ser permisivos, con una infeccion produtiva pero no citocidica. Se encontro que la fase de eclipse para el virus Pixuna en cultivo de embriones de 11 dias, estuvo entre los 15 y 90 min posteriores a la hora de adsorcion. La D-glucosamina no afecto el titulo infectivo del virus, usando embriones de 11 dias de edad como cultivo

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