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1.
New Phytol ; 227(6): 1790-1803, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32557686

RESUMO

The long-lived tree species Eschweilera tenuifolia (O. Berg) Miers is characteristic of oligotrophic Amazonian black-water floodplain forests (igapó), seasonally inundated up to 10 months per year, often forming monodominant stands. We investigated E. tenuifolia' growth and mortality patterns in undisturbed (Jaú National Park - JNP) and disturbed igapós (Uatumã Sustainable Development Reserve - USDR, downstream of the Balbina hydroelectric dam). We analysed age-diameter relationships, basal area increment (BAI) through 5-cm diameter classes, growth changes and growth ratios preceding death, BAI clustering, BAI ratio, and dated the individual year of death (14 C). Growth and mortality patterns were then related to climatic or anthropogenic disturbances. Results were similar for both populations for estimated maximum ages (JNP, 466 yr; USDR, 498 yr, except for one USDR tree with an estimated age of 820 yr) and slightly different for mean diameter increment (JNP: 2.04 mm; USDR: 2.28 mm). Living trees from JNP showed altered growth post-1975 and sparse tree mortality occurred at various times, possibly induced by extreme hydroclimatic events. In contrast with the JNP, abrupt growth changes and massive mortality occurred in the USDR after the dam construction began (1983). Even more than 30 yr after dam construction, flood-pulse alteration continues to affect both growth and mortality of E. tenuifolia. Besides its vulnerability to anthropogenic disturbances, this species is also susceptible to long-lasting dry and wet periods induced by climatic events, the combination of both processes may cause its local and regional extinction.


Assuntos
Inundações , Árvores , Florestas
3.
PLoS One ; 12(4): e0175003, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28394937

RESUMO

Wetlands harbor an important compliment of regional plant diversity, but in many regions data on wetland diversity and composition is still lacking, thus hindering our understanding of the processes that control it. While patterns of broad-scale terrestrial diversity and composition typically correlate with contemporary climate it is not clear to what extent patterns in wetlands are complimentary, or conflicting. To elucidate this, we consolidate data from wetland forest inventories in Brazil and examine patterns of diversity and composition along temperature and rainfall gradients spanning five biomes. We collated 196 floristic inventories covering an area >220 ha and including >260,000 woody individuals. We detected a total of 2,453 tree species, with the Amazon alone accounting for nearly half. Compositional patterns indicated differences in freshwater wetland floras among Brazilian biomes, although biomes with drier, more seasonal climates tended to have a larger proportion of more widely distributed species. Maximal alpha diversity increased with annual temperature, rainfall, and decreasing seasonality, patterns broadly consistent with upland vegetation communities. However, alpha diversity-climate relationships were only revealed at higher diversity values associated with the uppermost quantiles, and in most sites diversity varied irrespective of climate. Likewise, mean biome-level differences in alpha-diversity were unexpectedly modest, even in comparisons of savanna-area wetlands to those of nearby forested regions. We describe attenuated wetland climate-diversity relationships as a shifting balance of local and regional effects on species recruitment. Locally, excessive waterlogging strongly filters species able to colonize from regional pools. On the other hand, increased water availability can accommodate a rich community of drought-sensitive immigrant species that are able to track buffered wetland microclimates. We argue that environmental conditions in many wetlands are not homogeneous with respect to regional climate, and that responses of wetland tree communities to future climate change may lag behind that of non-wetland, terrestrial habitat.


Assuntos
Clima , Água Doce , Árvores , Áreas Alagadas , Biodiversidade , Brasil , Análise por Conglomerados , Florestas , Chuva , Análise de Regressão , Temperatura
4.
PLoS One ; 10(4): e0122542, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25837281

RESUMO

Matupás are floating vegetation islands found in floodplain lakes of the central Brazilian Amazon. They form initially from the agglomeration of aquatic vegetation, and through time can accumulate a substrate of organic matter sufficient to grow forest patches of several hectares in area and up to 12 m in height. There is little published information on matupás despite their singular characteristics and importance to local fauna and people. In this study we document the traditional ecological knowledge of riverine populations who live near and interact with matupás. We expected that their knowledge, acquired through long term observations and use in different stages of the matupá life cycle, could help clarify various aspects about the ecology and natural history of these islands that field biologists may not have had the opportunity to observe. Research was carried out in five riverine communities of the Amanã Sustainable Development Reserve (Brazil). Semi-structured interviews were conducted with 45 inhabitants in order to register local understandings of how matupás are formed, biotic/abiotic factors related to their occurrence, the plants and animals that occur on them, their ecological relevance, and local uses. Local people elucidated several little-known aspects about matupá ecology, especially regarding the importance of seasonal dynamics of high/low water for matupás formation and the relevance of these islands for fish populations. Soil from matupás is especially fertile and is frequently gathered for use in vegetable gardens. In some cases, crops are planted directly onto matupás, representing an incipient agricultural experiment that was previously undocumented in the Amazon. Matupás are also considered a strategic habitat for fishing, mainly for arapaima (Arapaima gigas). The systematic study of traditional ecological knowledge proved to be an important tool for understanding this little-known Amazonian landscape.


Assuntos
Florestas , Ilhas , Animais , Brasil , Conservação dos Recursos Naturais , Ecossistema , Peixes , Conhecimento , Rios
5.
J Pharm Biomed Anal ; 99: 89-96, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25108373

RESUMO

Eugenia calycina, which is described as "red pitanga or pitanga cherry of cerrado," is widely distributed in the Cerrado area of Brazil. Its leaf and bark extracts are used in folk medicine for many applications. In this study, the compositions of the major polar compounds of the bark and leaf extracts and their fractions were obtained from a liquid-liquid extraction using hexane, dichloromethane, ethyl acetate, and water. They were then evaluated using electrospray ionization negative FT-ICR mass spectrometry (ESI(-) FT-ICR MS), which revealed a large number of oxygen-containing compounds, such as flavonoids, terpenes, tanins, steroids, and fat acids. The biological activity of these extracts towards several bacterial and fungal strains was then evaluated. The highest activity was found using aqueous fractions, in which the ESI(-) FT-ICR MS analysis revealed compounds with a high content of oxygen (e.g., glycosed flavonoids, tannins, and polyphenolic compounds) against Cryptococcus sp. D (minimum inhibitory concentration [MIC]=15.62µg/mL). Strong activity was also found using the hexanic fractions-in which the ESI(-) FT-ICR MS analysis revealed that the compounds contained a decreased amount of oxygen (e.g., fat acids and steroids)-towards Cryptococcus gatti L48, Cryptococcus neoformans L3 (MIC=31.2µg/mL), and Cryptococcus sp. D (MIC=62.5µg/mL). Therefore, antimicrobial assays using the bark/leaf extracts of E. calycina present prospects for the research of active substances that may be used for the treatment of cryptococcosis, a disease that is common in immunosuppressed patients.


Assuntos
Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Flavonoides/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Syzygium/química , Taninos/isolamento & purificação , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Brasil , Candida/efeitos dos fármacos , Cryptococcus/efeitos dos fármacos , Flavonoides/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Medicina Tradicional , Testes de Sensibilidade Microbiana , Estrutura Molecular , Casca de Planta/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Taninos/farmacologia
6.
Bol. latinoam. Caribe plantas med. aromát ; 12(6): 572-580, nov. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-726591

RESUMO

The leaves of Myrcia tomentosa were collected from five sites and four different months in the Brazilian Cerrado and their essential oils were obtained by hidrodistillation and analyzed by GC/MS. The aim of this work was to evaluate the influence of environmental factors on essential oils composition in the leaves of M. tomentosa. The results were submitted to stepwise Multiple Regression and Canonical Correlation Analysis that indicated a relationship between compounds in essential oils and some environmental factors (foliar nutrients, soil nutrients and climatic data). Cluster Analysis indicated a high chemovariability in the essential oils from different sites, also showed that the collection time had a minor effect on oil composition.


Las hojas de Myrcia tomentosa se obtuvieron de cinco sitios diferentes y cuatro meses en el Cerrado brasileño y sus aceites esenciales fueron obtenidos por hidrodistillation y analizados por GC/MS. El objetivo de este trabajo fue evaluar la influencia de los factores ambientales sobre la composición de los aceites esenciales en las hojas de M. tomentosa. Los resultados fueron sometidos a múltiples etapas de regresión y análisis de correlación canónica indicó que la relación entre los compuestos en los aceites esenciales y algunos factores ambientales (nutrientes foliares, fertilizantes y datos climáticos). El análisis de agrupamiento indicó chemovariability un alto en los aceites esenciales de diferentes sitios, también mostró que el equipo de recolección tuvo un efecto menor sobre la composición del aceite.


Assuntos
Óleos Voláteis/química , Meio Ambiente , Myrtaceae/química , Plantas Medicinais/química , Clima , Fertilidade , Cromatografia Gasosa-Espectrometria de Massas , Folhas de Planta/química , Nutrientes , Micronutrientes , Estações do Ano , Solo
7.
Braz J Biol ; 73(1): 19-28, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23644785

RESUMO

The role of a dominant macrobenthic polychaete, Scolelepis squamata, in the colonisation of defaunated tropical sediments by sandy-beach nematodes was investigated and compared with a previous colonisation experiment carried out on a temperate sandy beach. Experimental cylinders, equipped with lateral windows allowing infaunal colonisation, were filled with defaunated sediment containing two treatments, with and without S. squamata. These cylinders were inserted into microcosms containing sediment with indigenous meiofauna collected from the field. The treatments were incubated in the laboratory at ambient temperature and salinity for 7, 14 and 21 days. The nematode assemblages in both treatments did not differ in composition between treatments and from the natural assemblages, suggesting that all the species were equally able to colonise the experimental cores. The presence of the polychaete did not affect the development of the nematode community composition, in contrast to the results from a previous temperate-beach experiment. However, our results did not indicate whether the difference in results was caused by the different behaviour of the polychaete specimens, or by the different composition and response of the present nematode community.


Assuntos
Praias , Biodiversidade , Sedimentos Geológicos/parasitologia , Poliquetos/classificação , Animais , Brasil , Monitoramento Ambiental , Densidade Demográfica
8.
Rev Bras Fisioter ; 15(5): 406-13, 2011.
Artigo em Inglês, Português | MEDLINE | ID: mdl-22031334

RESUMO

OBJECTIVES: The aim of this study was to determine the social-demographic, clinical, functional and psychological factors associated to activity restriction due to fear of falling in community-dwelling elderly and identify which variables best discriminate groups of elderly with different levels of activity restriction and fear of falling. METHODS: One hundred and thirteen community-dwelling elderly (74.5±7 years old) participated in the study. Activity restriction induced by fear of falling, previous falls, fall related self-efficacy, frailty phenotype, functional capacity, depressive symptoms, health self-perception, socio-demographic and clinical factors were assessed. Descriptive statistics, chi-square, ANOVA and Kruskal Wallis tests were used to analyze the associations between activity restriction due to fear of falling and all other variables. Path analysis (CHAID) method was used to verify which variables better discriminated groups in relation to activity restriction (α=0.05). RESULTS: The participants who reported fear of falling and activity restriction demonstrated higher depression (p=0.038), lower fall related self-efficacy (p<0.001), lower gait velocity (p=0.043) and independence level for instrumental daily living activities (p=0.017), higher number of diseases (p=0.048), worse health self-perception (p=0.040) and more depressive symptom (p=0.023). The best variables to discriminate groups were depression (p=0.004), exhaustion (frailty phenotype) (p=0.010) and social participation activities (p=0.016). CONCLUSION: Activity restriction due to fear of falling may have negative effects on functional capacity and psychological aspects in community-dwelling elderly. Psychosocial factors seem to better discriminate the elderly who avoid activities due to fear of falling.


Assuntos
Acidentes por Quedas , Atividades Cotidianas/psicologia , Medo , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Características de Residência , Inquéritos e Questionários
9.
Braz. j. phys. ther. (Impr.) ; 15(5): 406-413, Sept.-Oct. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-602746

RESUMO

OBJECTIVES: The aim of this study was to determine the social-demographic, clinical, functional and psychological factors associated to activity restriction due to fear of falling in community-dwelling elderly and identify which variables best discriminate groups of elderly with different levels of activity restriction and fear of falling. METHODS: One hundred and thirteen community-dwelling elderly (74.5±7 years old) participated in the study. Activity restriction induced by fear of falling, previous falls, fall related self-efficacy, frailty phenotype, functional capacity, depressive symptoms, health self-perception, socio-demographic and clinical factors were assessed. Descriptive statistics, chi-square, ANOVA and Kruskal Wallis tests were used to analyze the associations between activity restriction due to fear of falling and all other variables. Path analysis (CHAID) method was used to verify which variables better discriminated groups in relation to activity restriction (α=0.05). RESULTS: The participants who reported fear of falling and activity restriction demonstrated higher depression (p=0.038), lower fall related self-efficacy (p<0.001), lower gait velocity (p=0.043) and independence level for instrumental daily living activities (p=0.017), higher number of diseases (p=0.048), worse health self-perception (p=0.040) and more depressive symptom (p=0.023). The best variables to discriminate groups were depression (p=0.004), exhaustion (frailty phenotype) (p=0.010) and social participation activities (p=0.016). CONCLUSION: Activity restriction due to fear of falling may have negative effects on functional capacity and psychological aspects in community-dwelling elderly. Psychosocial factors seem to better discriminate the elderly who avoid activities due to fear of falling.


OBJETIVOS: Determinar os fatores sociodemograficos, clinicos, funcionais e psicologicos associados a restricao de atividades por medo de cair em idosos comunitarios e identificar quais variaveis melhor discriminam os grupos em relacao a restricao de atividades por medo de cair. MÉTODOS: Cento e treze idosos comunitarios (74,5±7 anos) participaram do estudo. Foram avaliados: restricao de atividades por medo de cair, historia de quedas, autoeficacia relacionada as quedas, fenotipo de fragilidade, aspectos sociodemograficos e clinicos, capacidade funcional, depressao e autopercepcao de saude. Estatisticas descritivas, teste qui-quadrado, ANOVA e o teste Kruskal-Wallis foram utilizados para analisar as relacoes entre a restricao de atividades por medo de cair e as outras variaveis. O metodo Chi-Square Automatic Interaction Detection (CHAID) foi utilizado para verificar quais variaveis melhor discriminavam os grupos em relacao a restricao de atividades (α=0,05). RESULTADOS: Idosos que relataram restricao de atividades por medo de cair apresentaram maior autorrelato de depressao (p=0,038), menor autoeficacia em relacao as quedas (p<0,001), menor velocidade de marcha (p=0,043) e nivel de independencia para realizacao de atividades instrumentais de vida diaria (p=0,017), maior numero de doencas (p=0,048), pior autopercepcao de saude (p=0,040) e maior presenca de sintomatologia depressiva (p=0,023). As variaveis que melhor discriminaram os grupos foram depressao (p=0,004), exaustao (fenotipo de fragilidade) (p=0,010) e participacao em atividades sociais (p=0,016). CONCLUSÃO: A restricao de atividades por medo de cair pode ter efeitos negativos na capacidade funcional e nos aspectos psicologicos de idosos comunitarios. Fatores psicossociais parecem discriminar melhor os idosos que apresentam restricao de atividades por medo de cair.


Assuntos
Idoso , Feminino , Humanos , Masculino , Acidentes por Quedas , Atividades Cotidianas/psicologia , Medo , Estudos Transversais , Características de Residência , Inquéritos e Questionários
10.
Rev. bras. farmacogn ; 20(6): 866-870, dez. 2010. graf, tab
Artigo em Português | LILACS | ID: lil-572623

RESUMO

As sementes de guaraná (Paullinia cupana Kunth, Sapindaceae) são utilizadas como estimulante e os principais constituintes químicos são as metilxantinas e os taninos, tais como catequina e epicatequina. Este trabalho teve por objetivo investigar um método por cromatografia líquida de alta eficiência (CLAE) para quantificar, simultaneamente, cafeína, teofilina, teobromina, catequina e epicatequina em pó de guaraná. Os valores obtidos foram comparados com os resultados encontrados no método espectrofotométrico da Farmacopéia Brasileira IV ed. Pelo método cromatográfico, os teores de metilxantinas e taninos totais foram de 4,04 por cento e 1,48 por cento, respectivamente. Os teores de metilxantinas e taninos totais, obtidos pelo método espectrofotométrico, foram de 4,88 por cento e 4,05 por cento, respectivamente. Acredita-se que, nas condições experimentais empregadas, o método espectrofotométrico não foi específico, quantificando outras substâncias fenólicas presentes no guaraná. Portanto, sugere-se o emprego desse método cromatográfico no controle de qualidade do guaraná em pó, por ser preciso, sensível, específico e rápido.


The seeds of Paullinia cupana Kunth, Sapindaceae, are used as a stimulant and the main chemical constituents are the methylxanthines and tannins, as catechin and epicatechin. This study aimed to investigate a method by high performance liquid chromatography (HPLC) to quantify both caffeine, theophylline, theobromine, catechin and epicatechin in powdered of P. cupana. The values obtained were compared with the results of the spectrophotometric method of the Brazilian Pharmacopoeia IV ed. For the chromatographic method, the levels of methylxanthines and total tannins were 4.04 percent and 1.48 percent, respectively. The levels of methylxanthines and total tannins obtained by the spectrophotometric method, were 4.88 percent and 4.05 percent, respectively. It is believed that, under our experimental conditions, the spectrophotometric method was not specific and quantified others phenolic substances present in the P. cupana. Therefore we suggest the use of this chromatographic method in quality control of P. cupana powder, to be accurate, sensitive, specific and fast.

11.
Rev Bras Fisioter ; 14(3): 237-43, 2010.
Artigo em Inglês, Português | MEDLINE | ID: mdl-20730369

RESUMO

OBJECTIVES: To culturally adapt the Falls Efficacy Scale-International (FES-I) and assess its psychometric properties in a sample of community-dwelling elderly Brazilians. METHODS: The instrument was translated into Brazilian Portuguese and culturally adapted to the Brazilian population (FES-I-Brazil) as recommended by the Prevention of Falls Network Europe. FES-I-Brazil was applied to 163 elderly people (73.44+/-5.51 years), and the demographic data and history of falls were also collected. From this group, 58 participants were randomly distributed to evaluate reliability. The reliability was analyzed using the intraclass correlation coefficient (ICC) and the internal consistency, using Cronbach's alpha coefficient (alpha). The internal structure of FES-I-Brazil was evaluated by means of exploratory factor analysis. The logistic regression model was used to determine which tasks on the scale were more relevant for discriminating falls. To analyze the sensitivity and specificity of FES-I-Brazil, the receiver operating characteristic (ROC) curve was used. RESULTS: The internal consistency of FES-I-Brazil was alpha=0.93, and the intra- and inter-examiner reliability were ICC=0.84 and 0.91, respectively. Factor analysis suggested two factors: concern about falling during social activities and activities of daily living (basic and instrumental), and postural control tasks. FES-I-Brazil scores > or = 23 suggested an association with a previous history of sporadic falls, whereas scores > or = 31 suggested an association with recurrent falls. CONCLUSIONS: FES-I-Brazil was shown to be semantically, linguistically and psychometrically appropriate to evaluate the fear of falling in the community-dwelling Brazilian elderly population.


Assuntos
Acidentes por Quedas , Características Culturais , Inquéritos e Questionários , Idoso , Brasil , Estudos Transversais , Feminino , Humanos , Internacionalidade , Masculino , Psicometria
12.
Braz. j. phys. ther. (Impr.) ; 14(3): 237-243, May-June 2010. tab, ilus
Artigo em Inglês, Português | LILACS | ID: lil-555149

RESUMO

OBJETIVOS: Adaptar culturalmente a Falls Efficacy Scale-International (FES-I) e avaliar suas propriedades psicométricas em uma amostra de idosos brasileiros da comunidade. MÉTODOS: Conforme recomendações da Rede Européia de prevenção às quedas, o instrumento foi traduzido para o português do Brasil e adaptado culturalmente para a população brasileira (FES-I-Brasil). A FES-I-Brasil foi aplicada em 163 idosos (73,44±5,51 anos), e foram coletados dados demográficos e relacionados à história de quedas. Dentre esses idosos, 58 foram distribuídos aleatoriamente para avaliação da confiabilidade. A confiabilidade foi analisada pelo Índice de Correlação Intraclasse (ICC) e a consistência interna pelo α de Cronbach. A estrutura interna da FES-I-Brasil foi avaliada pela análise fatorial exploratória. O modelo de regressão logística foi utilizado para identificar quais tarefas da escala eram mais relevantes para discriminar quedas. Para análise de sensibilidade e especificidade da FES-I-Brasil, empregou-se a curva Receiving Operator Characteristic (ROC). RESULTADOS: A consistência interna da FES-I-Brasil foi α=0,93, e a confiabilidade foi ICC=0,84 e 0,91 (intra e interexaminadores, respectivamente). A análise fatorial sugeriu dois fatores que verificavam preocupação em cair durante atividades de socialização e de vida diária (básicas e instrumentais) e tarefas relacionadas ao controle postural. Uma pontuação >23 pontos na FES-I-Brasil sugeriu associação com histórico de queda esporádica, ao passo que uma pontuação >31 pontos ensejou uma associação com queda recorrente. CONCLUSÕES: A FES-I-Brasil apresentou-se semântica, linguística e psicometricamente adequada para avaliar o medo de cair na população de idosos brasileiros da comunidade.


OBJECTIVES: To culturally adapt the Falls Efficacy Scale - International (FES-I) and assess its psychometric properties in a sample of community-dwelling elderly Brazilians. METHODS: The instrument was translated into Brazilian Portuguese and culturally adapted to the Brazilian population (FES-I-Brazil) as recommended by the Prevention of Falls Network Europe. FES-I-Brazil was applied to 163 elderly people (73.44±5.51 years), and the demographic data and history of falls were also collected. From this group, 58 participants were randomly distributed to evaluate reliability. The reliability was analyzed using the intraclass correlation coefficient (ICC) and the internal consistency, using Cronbach's alpha coefficient (α). The internal structure of FES-I-Brazil was evaluated by means of exploratory factor analysis. The logistic regression model was used to determine which tasks on the scale were more relevant for discriminating falls. To analyze the sensitivity and specificity of FES-I-Brazil, the receiver operating characteristic (ROC) curve was used. RESULTS: The internal consistency of FES-I-Brazil was α=0.93, and the intra- and inter-examiner reliability were ICC=0.84 and 0.91, respectively. Factor analysis suggested two factors: concern about falling during social activities and activities of daily living (basic and instrumental), and postural control tasks. FES-I-Brazil scores >23 suggested an association with a previous history of sporadic falls, whereas scores >31 suggested an association with recurrent falls. CONCLUSIONS: FES-I-Brazil was shown to be semantically, linguistically and psychometrically appropriate to evaluate the fear of falling in the community-dwelling Brazilian elderly population.


Assuntos
Idoso , Feminino , Humanos , Masculino , Acidentes por Quedas , Características Culturais , Inquéritos e Questionários , Brasil , Estudos Transversais , Internacionalidade , Psicometria
13.
Braz. j. microbiol ; 40(4): 790-794, Oct.-Dec. 2009. graf
Artigo em Inglês | LILACS | ID: lil-528161

RESUMO

Enzyme application in biotechnological and environmental processes has had increasing interest due to its efficiency, selectivity and mainly for being environmentally healthful, but these applications require a great volume of enzymes. In this work the effect of different concentrations of ethanol and 2,5 - xylidine on growth and production of laccase by Pycnoporus sanguineus was investigated. In a medium containing 200 mg.L-1 of 2,5 - xylidine or 50 g.L-1 of ethanol, the maximum activity of laccase was 2019 U.L-1 and 1035 U.L-1, respectively. No direct correlation between biomass and activity of laccase was observed for any of the inducers used during the tests. Ethanol concentrations, larger than or equal to 20 g.L-1, inhibited the radial growth of P. sanguineus. This study showed that ethanol, which has less toxicity and cost than the majority of the studied inducers, presents promising perspectives for laccase production by P. sanguineus.


Assuntos
Biomassa , Enzimas Reparadoras do DNA/análise , Etanol/análise , Fungos/enzimologia , Fungos/genética , Técnicas In Vitro , Lacase/análise , Ativação Enzimática , Métodos , Fenômenos Biológicos , Métodos
14.
Braz J Microbiol ; 40(4): 790-4, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24031426

RESUMO

Enzyme application in biotechnological and environmental processes has had increasing interest due to its efficiency, selectivity and mainly for being environmentally healthful, but these applications require a great volume of enzymes. In this work the effect of different concentrations of ethanol and 2,5-xylidine on growth and production of laccase by Pycnoporus sanguineus was investigated. In a medium containing 200 mg.L(-1) of 2,5-xylidine or 50 g.L(-1) of ethanol, the maximum activity of laccase was 2019 U.L(-1) and 1035 U.L(-1), respectively. No direct correlation between biomass and activity of laccase was observed for any of the inducers used during the tests. Ethanol concentrations, larger than or equal to 20 g.L(-1), inhibited the radial growth of P. sanguineus. This study showed that ethanol, which has less toxicity and cost than the majority of the studied inducers, presents promising perspectives for laccase production by P. sanguineus.

15.
Rev. bras. farmacogn ; 18(2): 265-278, abr.- jun. 2008. ilus, tab
Artigo em Português | LILACS | ID: lil-488666

RESUMO

O intuito deste trabalho de pesquisa foi obter parâmetros de controle de qualidade para a identificação da matéria-prima vegetal (folha) de Pimenta pseudocaryophyllus (Gomes) L. R. Landrum - Myrtaceae que ocorre no cerrado brasileiro. Para tanto foram coletadas amostras em Minas Gerais - Brasil e no Distrito Federal - Brasil e as exsicatas foram depositadas no Herbário da UFG n. UFG-27.159 e no Herbário Ezechias Paulo Heringer n. 21.745-0, respectivamente. Parte desse material botânico foi preparada para análises macro e microscópicas. Outra parte foi seca, triturada e usada para a triagem fitoquímica. O estudo mostrou que as folhas de P. pseudocaryophyllus são hipoestomáticas, têm grande quantidade de tricomas unicelulares na superfície abaxial, têm cavidades secretoras contendo compostos lipídicos e as células epidérmicas possuem paredes celulares espessas. Na triagem fitoquímica foram detectados compostos fenólicos, taninos e flavonóides. Os taninos foram dosados por diferentes métodos envolvendo reações colorimétricas e de precipitação com proteínas. Os diferentes resultados verificados chamam a atenção para a necessidade de se especificar o método utilizado juntamente com o limite mínimo de taninos totais estabelecido. Os resultados obtidos configuram-se como importantes parâmetros para o controle de qualidade da matéria-prima vegetal e denotam que a espécie em estudo possui um importante potencial fitoterápico que merece ser investigado em estudos farmacológicos e toxicológicos.


The goal of this research was to obtain quality control parameters for the identification of the plant drug of Pimenta pseudocaryophyllus (Gomes) L. R. Landrum that occurs in Brazilian savannah. So, two samples were collected, one in Minas Gerais state - Brazil, and the other one in Brasilia city - DF - Brazil, and the vouchers were deposited in the UFG Herbarium code number UFG-27159 and Ezechias Paulo Heringer Herbarium code number 21745-0, respectively. Part of the botanical material in both samples was prepared for microscopic analysis. The other one was air-dried, crushed to powder and used for phytochemical screening. The study has shown that P. pseudocaryophyllus leaves are hypostomatic, there are abundant unicellular trichomes in abaxial surface, there are secretory cavities with oily content and epidermal cells have thick wall. Tannins, phenolic compounds and flavonoids were detected in the phytochemical screening. The tannins had been quantified by different methods involving colorimetric and protein precipitation reactions, getting different results. This fact calls the attention for the necessity of specifying the method used together with the minimum tannins limit established. The results configure as important parameters for the quality control of the plant material and denote that the species in study take an important potential as herbal medicine that it deserves to be investigated in pharmacologic and toxicologic studies.

16.
Disasters ; 32(2): 303-15, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18380857

RESUMO

Analysis of the National Center for Health Statistics' Compressed Mortality File showed that between 1979 and 2004, natural events caused 21,491 deaths in the United States. During this 26-year period, there were 10,827 cold-related deaths and 5,279 heat-related deaths. Extreme cold or heat accounted for 75 per cent of the total number of deaths attributed to natural events--more than all of deaths resulting from lightning, storms and foods, and earth movements, such as earthquakes and landslides. Cold-related death rates were highest in the states of Alaska, Montana, New Mexico, and South Dakota, while heat-related deaths were highest in the states of Arizona, Missouri, and Arkansas. These deaths occurred more often among the elderly and black men. Other deaths were attributed to lightning (1,906), storms and foods (2,741), and earth movements (738). Most deaths associated with natural events are preventable and society can take action to decrease the morbidity and mortality connected with them.


Assuntos
Desastres/estatística & dados numéricos , Mortalidade , Feminino , Humanos , Raio , Masculino , Fatores de Tempo , Estados Unidos/epidemiologia , Tempo (Meteorologia)
17.
Rev Inst Med Trop Sao Paulo ; 49(2): 123-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17505674

RESUMO

Whooping cough or pertussis was a major cause of childhood morbidity and mortality in the world until the introduction of a whole-cell vaccine in the 1940's. However, since the early 1980's whooping cough cases have increased in many countries, becoming an important problem of public health. This increase may be due to accuracy of laboratory diagnosis and reporting of the disease, a decline in immunity over time, demographic changes, and adaptation of the bacterial population to vaccine-induced immunity. The purpose of this study was to analyze phenotypically and genotypically a collection of 67 Bordetella pertussis isolates recovered during the period 1988-2002 in São Paulo State, Brazil to determine their characteristics and relatedness. All isolates were submitted to susceptibility testing to erythromycin, serotyping, and 56 isolates were analyzed by Pulsed Field Gel Electrophoresis (PFGE). All isolates were susceptible to erythromycin and the majority of them belonged to serotype 1,3. The 56 isolates were classified into 11 PFGE profiles according to the differences in banding patterns. Although more than 60% of the isolates were recovered from patients aged less than three months, almost 15% of them were isolated from adolescents/adults evidencing the increase in the incidence of pertussis among this age group.


Assuntos
Bordetella pertussis/genética , Coqueluche/microbiologia , Adolescente , Adulto , Antibacterianos/farmacologia , Bordetella pertussis/efeitos dos fármacos , Bordetella pertussis/isolamento & purificação , Brasil , Criança , Pré-Escolar , Eletroforese em Gel de Campo Pulsado , Eritromicina/farmacologia , Genótipo , Humanos , Lactente , Recém-Nascido , Testes de Sensibilidade Microbiana , Fenótipo , Sorotipagem
18.
Rev. Inst. Med. Trop. Säo Paulo ; 49(2): 123-125, Mar.-Apr. 2007. tab
Artigo em Inglês | LILACS | ID: lil-449801

RESUMO

Whooping cough or pertussis was a major cause of childhood morbidity and mortality in the world until the introduction of a whole-cell vaccine in the 1940's. However, since the early 1980's whooping cough cases have increased in many countries, becoming an important problem of public health. This increase may be due to accuracy of laboratory diagnosis and reporting of the disease, a decline in immunity over time, demographic changes, and adaptation of the bacterial population to vaccine-induced immunity. The purpose of this study was to analyze phenotypically and genotypically a collection of 67 Bordetella pertussis isolates recovered during the period 1988-2002 in São Paulo State, Brazil to determine their characteristics and relatedness. All isolates were submitted to susceptibility testing to erythromycin, serotyping, and 56 isolates were analyzed by Pulsed Field Gel Electrophoresis (PFGE). All isolates were susceptible to erythromycin and the majority of them belonged to serotype 1,3. The 56 isolates were classified into 11 PFGE profiles according to the differences in banding patterns. Although more than 60 percent of the isolates were recovered from patients aged less than three months, almost 15 percent of them were isolated from adolescents/adults evidencing the increase in the incidence of pertussis among this group of age.


A coqueluche ou pertussis foi a maior causa de morbidade e mortalidade infantil em todo o mundo até a introdução de uma vacina na década de 1940. Entretanto, desde a década de 1980, a coqueluche tornou-se, em muitos países , um importante problema de saúde pública. Este acontecimento pode ser atribuído à melhoria do diagnóstico laboratorial e da notificação da doença, declínio da imunidade no decorrer do tempo, mudanças demográficas ou adaptação da população bacteriana à imunidade induzida pela vacina. O objetivo deste estudo foi analisar as características fenotípicas e genotípicas de uma coleção de 67 cepas de Bordetella pertussis isoladas no período 1988-2002 em São Paulo, Brasil. Todas as cepas foram submetidas à determinação do perfil de resistência à eritromicina, à sorotipagem e 56 cepas à eletroforese em campo pulsado (PFGE). Todas as cepas foram sensíveis à eritromicina e a maioria delas pertencia ao sorotipo 1,3. As 56 cepas foram classificadas em 11 perfis de PFGE com base nas diferenças no padrão de bandas. Embora mais de 60 por cento das cepas tenham sido isoladas de crianças com menos de três meses de idade, cerca de 15 por cento delas era de adolescentes/adultos evidenciando um aumento da incidência da coqueluche nesse grupo etário.


Assuntos
Humanos , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Bordetella pertussis/genética , Coqueluche/microbiologia , Antibacterianos/farmacologia , Brasil , Bordetella pertussis/efeitos dos fármacos , Bordetella pertussis/isolamento & purificação , Eletroforese em Gel de Campo Pulsado , Eritromicina/farmacologia , Genótipo , Testes de Sensibilidade Microbiana , Fenótipo , Sorotipagem
19.
Acta Otolaryngol ; 114(4): 415-22, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7976314

RESUMO

Otitis media was introduced in chinchillas by direct transbullar inoculation with either viable or formalin-inactivated Moraxella (Branhamella) catarrhalis. Both groups of animals developed middle ear fluids (MEF) and severe inflammatory changes in the tubotympanum. Pure cultures of M. catarrhalis were recovered for up to 5 days after inoculation from those animals inoculated with viable bacteria. Significantly elevated anti-M. catarrhalis antibody titers were detected in post-inoculation sera and in MEF or bullar lavages, and an increased number of IgG-bearing cells was also observed in the tubotympanum of these animals. Control chinchillas inoculated with pyrogen-free sterile saline failed to show any signs of otitis media. Our data indicate that viable M. catarrhalis induce acute otitis media in the chinchilla but that the bacteria are rapidly eliminated from the middle ear, precluding its usefulness as a model to study acute otitis media. Moreover, the same concentration of nonviable organisms also induces severe inflammatory changes in the middle ear. These data indicate that the chinchilla may be a useful model for studying the role of nonviable M. catarrhalis or its cell wall components on the induction and persistence of inflammation in the middle ear.


Assuntos
Moraxella catarrhalis , Infecções por Neisseriaceae , Otite Média/microbiologia , Animais , Anticorpos Antibacterianos/biossíntese , Cápsulas Bacterianas/fisiologia , Chinchila , Tecido Conjuntivo/patologia , Modelos Animais de Doenças , Orelha Média/microbiologia , Orelha Média/patologia , Edema/patologia , Tuba Auditiva/microbiologia , Tuba Auditiva/patologia , Imunoglobulina G/biossíntese , Contagem de Leucócitos , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Moraxella catarrhalis/imunologia , Moraxella catarrhalis/isolamento & purificação , Moraxella catarrhalis/fisiologia , Mucosa/patologia , Neutrófilos/patologia , Oligossacarídeos/imunologia , Oligossacarídeos/farmacologia , Otite Média/patologia , Otite Média com Derrame/microbiologia , Otite Média com Derrame/patologia , Fatores de Tempo , Membrana Timpânica/microbiologia , Membrana Timpânica/patologia
20.
Ciênc. cult. (Säo Paulo) ; 46(1/2): 82-5, Jan.-Abr. 1994. tab, graf
Artigo em Inglês | LILACS | ID: lil-172015

RESUMO

Estrogen is essential for growth and development of 30 per cent of malignant breast tumors and concentration of estrogen receptor (ER) is an indicator of hormone dependence. The effects of estradiol-l7beta (E2) on growth promotion and vitamin D (VDR) and progesterone (PR) receptor modulation were evaluated in hormone-dependent (MCF-7, T47D) and -independent (MDA-MB-231) breast carcinoma cells lines. 10(-7)M E2 stimulated the proliferation of MCF-7 and T47D cells the extent of which was correlated to ER content, being sensitive to growth inhibition of 10(-6) M tamoxifen. No effect on growth and PR levels was observed in E2 treated MDA-MB-231 cells. A statistically significant 10(-7)M E(2-)mediated induction of VDR was verified in T47D cells which was abolished by 10(-6)M tamoxifen, revealing an ER-mediated mechanism. 10(-6)M tamoxifen treatment alone upregulated VDR levels in T47D cells, suggesting that this drug may utilize a distinct pathway (ER-independent) for stimulation of VDR content, by a mechanism, now in progress, to be elucidated. These results, taken together, suggest the importance of VDR level assessment as new a prognostic indicator in breast carcinoma.


Assuntos
Humanos , Neoplasias da Mama/tratamento farmacológico , Estradiol/farmacologia , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Receptores de Calcitriol/efeitos dos fármacos , Receptores de Progesterona/efeitos dos fármacos , Tamoxifeno/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Divisão Celular , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias Hormônio-Dependentes/patologia , Células Tumorais Cultivadas/efeitos dos fármacos
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