453 research outputs found

    Effect of rhizome exposure to contrasting abiotic conditions on the performance of the invasive macrophyte Hedychium coronarium J. Koenig (Zingiberaceae)

    Get PDF
    Although invasive species are often better competitors than native species, broad environmental tolerance may also drive invasion success. Tolerance to abiotic heterogeneity in riparian ecosystems tends to favour the establishment of alien clonal species, as well as their dispersion by vegetative fragments. Hedychium coronarium J. Koenig is a rhizomatous emergent macrophyte native to Asia and has invaded Neotropical riparian ecosystems. We assessed the effect of H. coronarium rhizome exposure to distinct abiotic conditions on ramet growth. We exposed rhizomes to different desiccation periods (1–90 days), temperatures (15, 25 and 35 °C), and light regimes (0, 12, 16 h) and then assessed the effect of each of these variables on subsequent clonal growth (aboveground biomass production per plant and per ramet, and number and height of ramets) under ambient conditions. While no rhizome survived desiccation periods longer than 30 days, ramet growth among surviving rhizomes was not affected by the period of desiccation. Biomass production per rhizome, ramet biomass, and ramet height were significantly lower at 35 °C than at 25 °C. Constant darkness increased rhizome survival, but decreased ramet growth. Although rhizome exposure to extremes of each abiotic variable may hinder the invasion success of H. coronarium, the subsequent aboveground biomass production of surviving rhizomes did not decrease strongly in response to any treatment. This resilience may contribute to successful establishment of H. coronarium after dispersal through rhizome fragments and to varying abiotic conditions

    Espectroscopía Raman Intensificada por Superficie (SERS) en la identificación de microorganismos que producen biodeterioro: patrimonio edificado con arquitectura en tierra, Vale Histórico Paulista (São Paulo, Brasil)

    Get PDF
    El objetivo de este trabajo es presentar resultados obtenidos mediante análisis por espectroscopía Raman intensificada por superficie (SERS) como herramienta novedosa para la identificación taxonómica de hongos a partir de biofilms formados en paredes de arquitectura en tierra (“pau-a-pique”, “taipa de pilão”, y adobe), en edificaciones históricas del Vale Histórico de São Paulo, representativas del período colonial brasileño, Con el objetivo de abrir la posibilidad de clasificación de hongos mediante SERS, se seleccionaron colonias puras que fueron previamente aislados de las paredes de tierra e identificados por taxonomía clásica y biología molecular. Los géneros estudiados fueron: Trichoderma, Cladosporium, Aspergillus, Neurospora, Fusarium y Penicillium. Las colonias fueron cultivadas en PDA sólido. Se realizaron extractos en acetato de etilo que fueron mezclados con nanopartículas de oro en suspensión coloidal. Se observaron bandas características de grupos funcionales en la región entre 600 y 1800 cm-1 que presentaron diferencias para cada género. Análisis estadísticos de PCA y HCA mostraron relaciones que permitieron hacer asociaciones por género. Este trabajo es el primer reporte de comunidades microbianas a partir de paredes hechas con técnicas de arquitectura en tierra con el uso de Espectroscopía SERS

    Descriptions of two new Pseudophacopteron species (Hemiptera: Psylloidea: Phacopteronidae) inducing galls on Aspidosperma (Apocynaceae) in Brazil

    Get PDF
    Two new species of the large pantropical jumping plant-louse genus Pseudophacopteron Enderlein, 1921 (Hemiptera: Psylloidea: Phacopteronidae) are described from dry woodland habitats in the Midwest, Southeast and South of Brazil. Pseudophacopteron aspidospermi sp. nov. is associated with Aspidosperma australe, P. longicaudatum sp. nov. has been found on Aspidosperma macrocarpon and A. tomentosum (Apocynaceae). Both species induce intralaminar lenticular galls on the leaves of their host trees which have been the subject of several structural, histochemical and ecological publications. Adult males and females, fifth instar immatures and galls are illustrated including diagnostic morphological details, and compared with other Neotropical and Old World species of Pseudophacopteron and Phacopteronidae. The distribution of Pseudophacopteron in the Neotropical Region is briefl y discussed

    An endangered tree fern increases beta-diversity at a fine scale in the Atlantic Forest Ecosystem

    Get PDF
    R.N. and T.S.S. were funded by the Brazilian Government research support agency Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). A.E.M. acknowledges the ERC (BioTIME 250189 and BioCHANGE 727440) and the Royal Society. A.R.K. is funded by the Brazilian Science Without Borders scheme/CAPES (109113-1), D.M.S.M. acknowledges the CNPq (Fellowship of Research productivity 307839/2014-1).Some species make substantial contribution to habitat heterogeneity, supporting species coexistence. Dicksonia sellowiana Hook., an endangered tree fern, is a known phorophyte for epiphytes, has the potential to be such a taxon. We tested the hypothesis that D. sellowiana increases plant diversity in Brazilian Restinga forest, a biodiversity hotspot, by augmenting the habitat heterogeneity at a fine scale. To do this we quantified α-diversity and β-diversity in three habitat types: on the tree fern trunks, immediately beneath the trunks and away from the trunks. In total, 40 ferns were sampled. Overall we recorded 2602 individuals belonging to 61 phanerophyte species in 30 families. The number of individuals sampled varied among habitats but rarefaction showed that richness did not differ. In contrast, species composition varied markedly amongst habitats. Both statistical approaches detected high levels of β-diversity, particularly between the species found in the vicinity of the fern, and those in the samples away from the trunks. Indicator species analysis was used to identify the species characteristic of the different habitats. About 30% of the species were exclusively found in “away plots”, 17% were exclusively “below plots” and 15% were found only on the trunks, 13% were found on the trunks and below them, 12% on “bellow” and “away plots”, 10% of species occurred in all areas and 3% were found on trunks and “away plots”. Our results lead us to conclude that the endangered fern D. sellowiana plays an important role in promoting habitat heterogeneity within the Restinga forest. As this iconic species is threatened, its overexploitation may lead to impoverishment of plant communities. Conservation effort towards both the area and this species are crucial to maintaining Restinga plant diversity.PostprintPeer reviewe

    Patologia da infecção experimental de roedores domésticos com diferentes cepas de Yersinia pestis

    Get PDF
    Os autores estudaram 253 ratos domésticos (Rattus norvegicus e Rattus r. frugivorus), infectados experimentalmente (via subcutânea) com duas cepas de Yersinia pestis (cepas "PEXU-19" e "RANGEL"), isoladas de roedores silvestres capturados no nordeste brasileiro (Exú - Pernambuco) e na Venezuela, respectivamente, as quais foram mantidas em meio de cultura e subinoculadas periodicamente. A sobrevida dos animais infectados variou de dois a sete dias, sendo os sobreviventes sacrificados no 20º dia após a data da inoculação. Para cada uma das duas espécies de rato, foram empregadas cargas infectantes de intensidades diferentes (750 - 4.250; 7.500 - 41.250 e 75.000 - 750.000 bacilos), correspondentes a cada uma das duas cepas de Y. pestis utilizadas. A patologia foi estudada em relação ao fígado, baço, pulmão e linfonodo inguinal, órgãos onde as lesões se mostraram mais exuberantes. As lesões hepáticas foram essencialmente representadas por congestão, necrose coagulativa multifocal e infiltração inflamatória aguda portal e sinusoidal, com formação de microabscessos. No baço ocorreu atrofia acentuada dos folículos linfóides de Malpighi, congestão, hemorragia e esplemite aguda abscedada. No pulmão, foi achado freqüente a pneumonite aguda, ás vezes acompanhada de abscessos. De um modo geral, a cepa PEXU-19 revelou maior poder patogênico que a cepa RANGEL, embora, em relação à espécie de roedor infectado não tenha sido possível surpreender diferenças quanto á sua susceptibilidade frente ás duas cepas Y. pestis utilizadas no presente trabalho.Two hundred and fifty three domestic rats (Rattus norvegicus and Rattus r. frugivorus) were experimentally infected with two different strains of Yersinia pestis ("Pexu-19" and "Rangel") by subcutaneous route. These strains were isolated from wild rodents from Northeast Brazil (Exu, Pernambuco State) and Venezuela, respectively. Thenceforth, they were maintained in culture and subinoculated into susceptible laboratory mice periodically. The survival of the infected rats varied from two to seven days. The animals which live longer were killed twenty days after inoculation. Three different inocula were used in each host (750- 4.250, 7.500 - 41.250 and 75.000 - 750.000 bacilli). the pathological lesions were studied in the liver, spleen, lungs and inguinal lymph node where the lesions were found to be more frequent. The liver lesions consisted of congestion, multifocal coagulative necrosis and acute inflammatory infiltration of portal tracts and sinusoides, with formation of microabscesses. In spleen there was a marked atrophy of the malpighian lymphoid folliches, as well as congestion, haemorrhages and acute splenitis with abscess formation. In lungs, acute pneumonitis was almost invariabby found, sometimes followed by abscess formation. The brazilian strain ("Pexu-19") showed a higher pathogenic power when compared to the venezuelan strain ("Rangel"). However, no difference was detected between the species used as experimental hosts since both of them showed a similar susceptibility to the two strains of Yersinia pestis utilized in the present investigation

    A violência no eixo Brasília-Goiânia

    Get PDF
    Além do desenvolvimento econômico e do crescimento populacional, algumas cidades do eixo Brasília-Goiânia se destacampelos elevados índices de violência. Três regiões merecem destaque: o Distrito Federal, a Área Metropolitana de Brasília e aRegião Metropolitana de Goiás. Neste artigo, analisa-se brevemente a evolução dos homicídios nessas regiões

    Generalized anxiety disorder in a population aged 80 years and older

    Get PDF
    OBJECTIVE: To describe the prevalence of generalized anxiety disorder (GAD) in a community-dwelling population aged 80 years and older. Also, to compare sleep patterns, cognitive function and prevalence rate of other psychiatric conditions between healthy controls and GAD subjects. METHODS: DSM-IV criteria were used to diagnose GAD. A representative random sample of 77 community-dwelling subjects (35%), aged 80 years or more from the rural southern county of Veranopolis, Brazil, was selected. Sleep patterns were assessed using the Pittsburgh Sleep Quality Index and a 2-week sleep/wake diary. Five neuropsychological tests (Buschke-Fuld Selective Reminding Test, CERAD word list, verbal fluency test, and two sub-tests of the Wechsler memory scale) were used for cognitive evaluation. RESULTS: The estimated GAD prevalence was 10.6 percent. GAD was associated with major depression, with a significant greater number of depressive symptoms as measured by the Geriatric Depression Scale and with a significant more frequent occurrence of minor depression. Sleeping patterns and cognition function among GAD subjects were not compromised. The severity of physical diseases was similar in both GAD subjects and healthy controls. GAD was associated with a significantly lower health-related quality of life. CONCLUSIONS: In comparison with previous studies, the prevalence of GAD is higher in the studied population. This disorder is frequently associated with both depressive symptoms and a lower health-related quality of life.OBJETIVOS: Descrever a prevalência de transtorno de ansiedade generalizada (TAG) em uma população de idosos residentes em uma comunidade e com idade acima de 80 anos e comparar os padrões de sono, a função cognitiva e a taxa de prevalência de outros diagnósticos psiquiátricos entre controles normais e sujeitos com TAG. MÉTODOS: Para o diagnóstico de TAG, foram utilizados os critérios do Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Selecionou-se uma amostra randômica e representativa de 77 sujeitos (35%), residentes em uma comunidade, entre todos os idosos com idade acima de 80 anos do município Veranópolis, RS. Os padrões de sono foram aferidos pelo índice de qualidade de sono de Pittsburgh e pelo diário sobre sono/vigília a ser preenchido ao longo de duas semanas. Cinco testes neuropsicológicos foram usados na avaliação cognitiva: teste das lembranças seletivas de Buschke-Fuld; lista de palavras da bateria CERAD (Consortium to Establish a Registry for Alzheimer's Disease); teste de fluência verbal e dois subtestes da escala de memória Wechsler. RESULTADOS: A prevalência estimada de TAG foi de 10,6%, cuja presença estava associada a uma maior ocorrência de depressão clinicamente diagnosticável, com um significativo maior número de sintomas depressivos, quando medidos pela escala de depressão geriátrica, e com uma maior ocorrência de depressão menor. Os padrões de sono e o funcionamento cognitivo, entre sujeitos com TAG, não estavam afetados. A gravidade das doenças físicas não variava entre sujeitos com TAG e os controles normais. A presença de TAG estava associada a um significativo pior padrão de qualidade de vida relativa à saúde. CONCLUSÃO: Em comparação com os estudos prévios, a prevalência de TAG é alta entre a população de idosos mais velhos. Esse transtorno ocorre em freqüente associação com a sintomatologia depressiva e também está associado a um pior padrão de qualidade de vida relativa à saúde.Instituto de Geriatria e Gerontologia Associação de Neuropsicologia do IdosoUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina (UNIFESP/EPM) Departamento de PsiquiatriaUNIFESP-EPM Departamento de NeurologiaUNIFESP-EPM Departamento de PsicobiologiaUNIFESP, EPM, (UNIFESP/EPM) Depto. de PsiquiatriaUNIFESP, EPM Depto. de NeurologiaUNIFESP, EPM Depto. de PsicobiologiaSciEL

    Differential regulation of PGC-1α expression in rat liver and skeletal muscle in response to voluntary running

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The beneficial actions of exercise training on lipid, glucose and energy metabolism and insulin sensitivity appear to be in part mediated by PGC-1α. Previous studies have shown that spontaneously exercised rats show at rest enhanced responsiveness to exogenous insulin, lower plasma insulin levels and increased skeletal muscle insulin sensitivity. This study was initiated to examine the functional interaction between exercise-induced modulation of skeletal muscle and liver PGC-1α protein expression, whole body insulin sensitivity, and circulating FFA levels as a measure of whole body fatty acid (lipid) metabolism.</p> <p>Methods</p> <p>Two groups of male Wistar rats (2 Mo of age, 188.82 ± 2.77 g BW) were used in this study. One group consisted of control rats placed in standard laboratory cages. Exercising rats were housed individually in cages equipped with running wheels and allowed to run at their own pace for 5 weeks. At the end of exercise training, insulin sensitivity was evaluated by comparing steady-state plasma glucose (SSPG) concentrations at constant plasma insulin levels attained during the continuous infusion of glucose and insulin to each experimental group. Subsequently, soleus and plantaris muscle and liver samples were collected and quantified for PGC-1α protein expression by Western blotting. Collected blood samples were analyzed for glucose, insulin and FFA concentrations.</p> <p>Results</p> <p>Rats housed in the exercise wheel cages demonstrated almost linear increases in running activity with advancing time reaching to maximum value around 4 weeks. On an average, the rats ran a mean (Mean ± SE) of 4.102 ± 0.747 km/day and consumed significantly more food as compared to sedentary controls (<it>P </it>< 0.001) in order to meet their increased caloric requirement. Mean plasma insulin (<it>P </it>< 0.001) and FFA (<it>P </it>< 0.006) concentrations were lower in the exercise-trained rats as compared to sedentary controls. Mean steady state plasma insulin (SSPI) and glucose (SSPG) concentrations were not significantly different in sedentary control rats as compared to exercise-trained animals. Plantaris PGC-1α protein expression increased significantly from a 1.11 ± 0.12 in the sedentary rats to 1.74 ± 0.09 in exercising rats (<it>P </it>< 0.001). However, exercise had no effect on PGC-1α protein content in either soleus muscle or liver tissue. These results indicate that exercise training selectively up regulates the PGC-1α protein expression in high-oxidative fast skeletal muscle type such as plantaris muscle.</p> <p>Conclusion</p> <p>These data suggest that PGC-1α most likely plays a restricted role in exercise-mediated improvements in insulin resistance (sensitivity) and lowering of circulating FFA levels.</p

    Crescimento e diferenciação "In vitro" de cepas de Trypanosoma cruzi, isoladas de animais silvestres

    Get PDF
    In the course of this work, four strains of sylvatic Trypanosoma cruzi were studied in regard to their growth and differentiation in LIT medium. R52, R64, and R65 were isolated from individual Didelphis albiventris (Marsupialia) and M226 from Calomys callosus (Rodentia). The evolution of the numerical incresase and morphogenesis of the trypanosome populations in the culture was observed at regular intervals during a period of 312 hours. Differential counts were made of amastigotes, epimastigotes, and trypomastigotes in Neubauer chambers. Results showed that the four strains had characteristic behavior patterns. M226 increased the most and was followed by R65, R52, and then R64.Foram estudadas três cepas de T. cruzi isoladas de Didelphis albiventris (R52, R64 e R65) e uma isolada de Calomys callosus (M226), quanto ao comportamento "In vitro" no meio LIT. A evolução da população dos tripanossomas com relação ao crescimento e morfogênese foi acompanhada por um período de 13 dias (312 horas), em intervalos regulares. As contagens diferenciais, separando-se formas amastigotas, epimastigotas e tripomastigotas, foram realizadas na câmara de Neubauer. Os resultados obtidos levaram à conclusão de que as 4 cepas estudadas têm comportamento distintos. O melhor crescimento obtido ocorreu para a cepa M226, seguindo-se por ordem decrescente a R65, R52 e R64. Os picos das populações ocorreram como segue: M226, entre 192-264 horas; R65 entre 168-240 horas; R52 às 240 horas e R64 entre 264-312 horas
    corecore