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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469273

RESUMO

Abstract The objective of this study was to assess air quality in relation to vehicular traffic flow in cities located at different elevations in the Bodoquena microregion, state of Mato Grosso do Sul, Brazil. To do so, a micronucleus test was carried out using the TRAD-MCN bioassay on young Tradescantia buds collected from February to November 2018 in seven cities of the microregion with different traffic flow intensities. Meteorological parameters were evaluated, and vehicular traffic was counted to determine traffic flow in each city. With data from the Shuttle Radar Topography Mission (SRTM) and processing in Esri ArcGIS® software version 10.5.1, the regions was mapped based on an Elevation Model. Morphoanatomical analyses were performed according to standard methodology. Measurements were taken of thickness, length and width of tissues and structures, including the upper and lower cuticle, upper and lower epidermis, hypodermis and mesophyll. The greatest traffic flow was found in the cities of Bodoquena, Guia Lopes da Laguna, Jardim, and Porto Murtinho, with the period from 5:00 to 6:00 p.m. showing the highest traffic flow. The greatest frequency of mutagenic alterations was found in the city of Guia Lopes da Laguna, although the results did not differ significantly from Bonito, Caracol, and Jardim. Throughout the biomonitoring, the summer and autumn seasons showed the greatest micronuclei frequencies in all evaluated cities. Variations in the tissue/structure thickness was observed across cities and seasons, but with a decrease in thickness during autumn. In general, the tissues/structures were smaller for the cities of Nioaque and Porto Murtinho, while the anatomical and morphological characteristics of leaf length and thickness showed no differences among cities. We found limited correlation between micronuclei frequency and traffic flow, supporting the hypothesis that although mutagenic alterations are observed in T. pallida, in this microregion the changes are numerically lower when compared to other regions of the state. In light of the genotoxic and morphoanatomical factors assessed herein, the Bodoquena microregion appears to be well preserved in terms of air quality, presenting low micronuclei frequency and a limited reduction in tissues and leaf structures, regardless of the season.


Resumo O objetivo deste trabalho foi avaliar a qualidade do ar com base no fluxo veicular das cidades localizadas em diferentes altitudes na microrregião da Bodoquena, no estado de Mato Grosso do Sul, Brasil. Para tal, foi realizado o teste de micronúcleo, por meio do bioensaio TRAD-MCN em botões jovens de Tradescantia coletadas no período entre fevereiro a novembro de 2018 em sete cidades da microrregião da Bodoquena, com diferentes intensidades de fluxo veicular. Foram avaliados os parâmetros meteorológicos, os veículos foram contados para determinar o tráfego de veículos em cada cidade e altitude. A partir da topografia Shuttle Radar (SRTM) e processamento no software Esri ArcGIS® versão 10.5.1 foi possível mapear a área com base no Modelo de Elevação. As análises morfoanatômicos foram realizadas conforme metodologia padrão. As mensurações de espessura, comprimento, largura dos tecidos e estruturas como a cutícula superior, cutícula inferior, face superior e face inferior da epiderme, hipoderme e mesófilo foram avaliadas. O maior fluxo veicular foi encontrado nas cidades de Bodoquena, Guia Lopes da Laguna, Jardim e Porto Murtinho. O horário das 17:00 às 18:00h foi o que apresentou maiores fluxo de veículos. A maior frequência de alterações mutagênicas foi encontrada na cidade de Guia Lopes, não diferindo de Bonito, Caracol e Jardim. Ao longo do biomonitoramento observou-se que as estações de verão e outono foram as que apresentaram maiores frequências de micronúcleo independente da cidade avaliada. Observou-se que a correlação entre a frequência de micronúcleos e o fluxo veicular foi baixa, apoiando a tese de que essa microrregião, embora apresente alterações mutagênicas em T. pallida, as alterações numericamente são pequenas quando comparadas a outras regiões do estado de Mato Grosso do Sul. Observou-se uma variação na espessura dos tecidos/estruturas que é variável entre as diferentes cidades e estações do ano. De forma geral os tecidos/estrutura apresentaram redução na espessura para as cidades de Nioaque e Porto Murtinho quanto aos aspectos anatômicos e morfológicos, sendo que, para o comprimento e espessura foliar não foi observado diferenças entre as cidades. Em relação as estações do ano, observou-se que no outono a espessura dos tecidos/estruturas são menores. Diante dos fatores genotóxicos e morfoanatômicos aqui avaliados, a microrregião da Bodoquena parece estar bem preservada em termos de qualidade do ar, apresentando baixa frequência de micronúcleos e redução limitada de tecidos e estruturas foliares, independentemente da estação do ano.

2.
Braz J Biol ; 84: e250100, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34932674

RESUMO

The objective of this study was to assess air quality in relation to vehicular traffic flow in cities located at different elevations in the Bodoquena microregion, state of Mato Grosso do Sul, Brazil. To do so, a micronucleus test was carried out using the TRAD-MCN bioassay on young Tradescantia buds collected from February to November 2018 in seven cities of the microregion with different traffic flow intensities. Meteorological parameters were evaluated, and vehicular traffic was counted to determine traffic flow in each city. With data from the Shuttle Radar Topography Mission (SRTM) and processing in Esri ArcGIS® software version 10.5.1, the regions was mapped based on an Elevation Model. Morphoanatomical analyses were performed according to standard methodology. Measurements were taken of thickness, length and width of tissues and structures, including the upper and lower cuticle, upper and lower epidermis, hypodermis and mesophyll. The greatest traffic flow was found in the cities of Bodoquena, Guia Lopes da Laguna, Jardim, and Porto Murtinho, with the period from 5:00 to 6:00 p.m. showing the highest traffic flow. The greatest frequency of mutagenic alterations was found in the city of Guia Lopes da Laguna, although the results did not differ significantly from Bonito, Caracol, and Jardim. Throughout the biomonitoring, the summer and autumn seasons showed the greatest micronuclei frequencies in all evaluated cities. Variations in the tissue/structure thickness was observed across cities and seasons, but with a decrease in thickness during autumn. In general, the tissues/structures were smaller for the cities of Nioaque and Porto Murtinho, while the anatomical and morphological characteristics of leaf length and thickness showed no differences among cities. We found limited correlation between micronuclei frequency and traffic flow, supporting the hypothesis that although mutagenic alterations are observed in T. pallida, in this microregion the changes are numerically lower when compared to other regions of the state. In light of the genotoxic and morphoanatomical factors assessed herein, the Bodoquena microregion appears to be well preserved in terms of air quality, presenting low micronuclei frequency and a limited reduction in tissues and leaf structures, regardless of the season.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Tradescantia , Poluentes Atmosféricos/toxicidade , Monitoramento Biológico , Brasil , Monitoramento Ambiental , Testes para Micronúcleos , Mutagênicos , Tradescantia/genética , Emissões de Veículos/toxicidade
3.
Nefrología (Madr.) ; 31(4): 464-470, jul.-ago. 2011. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-103227

RESUMO

Antecedentes: La isquemia-reperfusión es causa fundamental de complicaciones renales. La lesión más frecuente es la necrosis tubular aguda (NTA). En modelos de isquemia-reperfusión se ha demostrado que el precondicionamiento oxidativo con ozono ejerce un efecto modulador del estado redox de las células renales, al estimular los mecanismos antioxidantes endógenos. Trabajos más recientes, que han empleado el postcondicionamiento isquémico, han obtenido resultados similares. Objetivos: Evaluar el efecto del poscondicionamiento oxidativo con ozono sobre la morfología y la función renal en un modelo de isquemia-reperfusión en ratas. Métodos: Se utilizaron 40 ratas Wistar hembras con un peso entre 150 y 200 g, divididas al azar en cuatro grupos (control negativo, control positivo, oxígeno y ozono). Los grupos control positivo, oxígeno y ozono fueron sometidos a 60 minutos de isquemia y 10 días de reperfusión. Durante la reperfusión al grupo oxígeno se le administraron 26 mg/kg de peso corporal de oxígeno y al grupo ozono, 0,5 mg/kg de peso corporal de ozono, por vía rectal. Al final del experimento se tomaron muestras de orina y de sangre para las pruebas de función renal y se extrajeron los riñones para el estudio histológico. Resultados: El grupo ozono no mostró diferencias significativas en los valores de fracción de filtración y proteinuria con respecto al grupo control negativo. Los valores de intensidad de filtrado glomerular, flujo plasmático renal y creatinina mostraron una mejoría ligera en comparación con los grupos oxígeno y control positivo. El grupo ozono mostró de forma significativa un menor daño histológico global que los grupos control positivo y oxígeno. Conclusiones: El poscondicionamiento con ozono tuvo un efecto protector (AU)


Background: Ischaemia-reperfusion is one of the main causes of kidney complications. The most frequent lesion is acute tubular necrosis. Ozone oxidative preconditioning exerts a modulatory effect of redox state of renal cells in models of ischaemia-reperfusion, by stimulating endogenous antioxidant mechanisms. Similar results have been obtained in more recent studies using ischaemic postconditioning. Objectives: To evaluate the effect of ozone oxidative postconditioning on renal function and morphology in an ischaemia-reperfusion rat model. Methods: We used forty female Wistar rats weighing between 150g-200g randomly divided into 4 groups (negative control, positive control, oxygen and ozone). The groups: positive control, oxygen and ozone were subjected to 60 minutes of ischaemia and 10 days of reperfusion. During reperfusion, the oxygen group was given 26mg/kg body weight of oxygen, and the ozone group 0.5mg/kg body weight of ozone, rectally. At the end of the experiment urine and blood samples were taken for renal function tests and kidneys were removed for histological study. Results: The ozone group showed no significant differences for filtration fraction and proteinuria compared to the negative control group. The glomerular filtrate rate, renal plasma flow and creatinine showed a slight improvement in comparison with oxygen and positive control groups. The ozone group showed significantly less overall histological damage than the positive control and oxygen groups. Conclusions: Ozone postconditioning showed to have a protective effect in preserving renal function and morphology (AU)


Assuntos
Animais , Ratos , Necrose Tubular Aguda/prevenção & controle , Ozônio/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Testes de Função Renal , Modelos Animais de Doenças
4.
Nefrologia ; 31(4): 464-70, 2011.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-21738249

RESUMO

BACKGROUND: Ischaemia-reperfusion is one of the main causes of kidney complications. The most frequent lesion is acute tubular necrosis. Ozone oxidative preconditioning exerts a modulatory effect of redox state of renal cells in models of ischaemia-reperfusion, by stimulating endogenous antioxidant mechanisms. Similar results have been obtained in more recent studies using ischaemic postconditioning. OBJECTIVES: To evaluate the effect of ozone oxidative postconditioning on renal function and morphology in an ischaemia-reperfusion rat model. METHODS: We used forty female Wistar rats weighing between 150g-200g randomly divided into 4 groups (negative control, positive control, oxygen and ozone). The groups: positive control, oxygen and ozone were subjected to 60 minutes of ischaemia and 10 days of reperfusion. During reperfusion, the oxygen group was given 26mg/kg body weight of oxygen, and the ozone group 0.5mg/kg body weight of ozone, rectally. At the end of the experiment urine and blood samples were taken for renal function tests and kidneys were removed for histological study. RESULTS: The ozone group showed no significant differences for filtration fraction and proteinuria compared to the negative control group. The glomerular filtrate rate, renal plasma flow and creatinine showed a slight improvement in comparison with oxygen and positive control groups. The ozone group showed significantly less overall histological damage than the positive control and oxygen groups. CONCLUSIONS: Ozone postconditioning showed to have a protective effect in preserving renal function and morphology.


Assuntos
Isquemia/tratamento farmacológico , Rim/irrigação sanguínea , Ozônio/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Administração Retal , Animais , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos , Feminino , Taxa de Filtração Glomerular , Rim/patologia , Rim/fisiopatologia , Necrose Tubular Aguda/tratamento farmacológico , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/patologia , Necrose Tubular Aguda/prevenção & controle , Masculino , Oxigênio/administração & dosagem , Oxigênio/uso terapêutico , Ozônio/administração & dosagem , Proteinúria/etiologia , Proteinúria/prevenção & controle , Distribuição Aleatória , Ratos , Ratos Wistar , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia
5.
Theor Appl Genet ; 104(6-7): 916-925, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12582596

RESUMO

As an approach to isolate novel cereal promoters, promoterless uidA constructs and particle bombardment were used to transform tritordeum. Five of eight transgenic lines containing uidA sequences showed evidence of promoter tagging. Expression of uidA was detected in four lines as: constitutive expression, expression in short cells of the epidermis of the spikelets, expression in pollen grains and in cells of the epidermis of the spikelet, and expression in anther primordia and pollen grains. In the fifth line, the uidA was shown by RT-PCR to be transcribed, but no GUS activity was detected. The different patterns of uidA expression indicate that different regulatory sequences were tagged in each of these lines. Analysis of the progeny resulting from self-fertilisation of the primary tagged plants, indicate that the transgenes integrated at one or two loci and the patterns of expression were stably inherited. To our knowledge, this is the first report of promoter tagging in cereals by direct gene transfer.

6.
Plant Mol Biol ; 42(4): 615-22, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10809007

RESUMO

The promoterless maize ubiquitin first exon and intron fragment can drive gusA expression in immature tritordeum inflorescences and immature wheat scutella. In fluorescence assays, this fragment induces gusA expression in tritordeum inflorescences to 50 times higher than background. The activity of the complete promoter, exon and intron cassette was up to 20000-fold higher than background but the maize ubiquitin promoter in isolation had very low activity. A construct with the maize alcohol dehydrogenase first exon and intron had low activity, visible in histochemical assays. Both intron sequences have promoter-like features and in the ubiquitin intron there is a sequence homologous to the opaque-2-binding box. We suggest that the combination of these elements may explain the promoter activity detected in these introns.


Assuntos
Glucuronidase/genética , Hordeum/genética , Íntrons/genética , Triticum/genética , Álcool Desidrogenase/genética , Regulação Enzimológica da Expressão Gênica , Técnicas Genéticas , Glucuronidase/metabolismo , Estruturas Vegetais/genética , Plantas Geneticamente Modificadas , Plasmídeos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Zea mays/enzimologia
7.
Z Naturforsch C J Biosci ; 54(11): 963-71, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10627996

RESUMO

A gene coding for a soluble protein with homology to the beta subunit of the nicotinic acetylcholine receptor from goldfish was isolated from a cDNA library of Haementeria ghilianii salivary glands. Comparison of the leech protein sequence with the database showed that the N terminus has high homology with the extracellular portion of acetylcholine receptor beta subunits, whilst the C terminus, highly charged, has homology to proteins which may be involved in chelating divalent cations. The leech protein was expressed in mammalian cells and the product compared to the native protein. Both proteins are glycosylated and form polymers which are disrupted by heat but not by reducing agents. A role for this protein in salivary gland secretion is suggested.


Assuntos
Receptores Nicotínicos/química , Receptores Nicotínicos/genética , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Biblioteca Gênica , Carpa Dourada , Hemoglobinas/química , Sanguessugas , Substâncias Macromoleculares , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas e Peptídeos Salivares/isolamento & purificação , Schistosoma mansoni/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
8.
Appl Environ Microbiol ; 54(4): 903-9, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16347612

RESUMO

Ethanol stimulated the leakage of amino acids and 260-nm-light-absorbing compounds from cells of Saccharomyces cerevisiae. The efflux followed first-order kinetics over an initial period. In the presence of lethal concentrations of ethanol, the efflux rates at 30 and 36 degrees C were an exponential function of ethanol concentration: k(e) = k(e)e, where k(e) and k(e) are the efflux rate constants, respectively, in the presence of a concentration X of ethanol or the minimal concentration of ethanol, X(m), above which the equation was applicable, coincident with the minimal lethal concentration of ethanol. E is the enhancement constant. At 36 degrees C, as compared with the corresponding values at 30 degrees C, the efflux rates were higher and the minimal concentration of ethanol (X(m)) was lower. The exponential constants for the enhancement of the rate of leakage (E) had similar values at 30 or 36 degrees C and were of the same order of magnitude as the corresponding exponential constants for ethanol-induced death. Under isothermic conditions (30 degrees C) and up to 22% (vol/vol) ethanol, the resistance to ethanol-induced leakage of 260-nm-light-absorbing compounds was found to be closely related with the ethanol tolerance of three strains of yeasts, Kluyveromyces marxianus, Saccharomyces cerevisiae, and Saccharomyces bayanus. The resistance to ethanol-induced leakage indicates the possible adoption of the present method for the rapid screening of ethanol-tolerant strains. The addition to a fermentation medium of the intracellular material obtained by ethanol permeabilization of yeast cells led to improvements in alcohol fermentation by S. cerevisiae and S. bayanus. The action of the intracellular material, by improving yeast ethanol tolerance, and the advantages of partially recycling the fermented medium after distillation were discussed.

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