991 resultados para Pectobacterium carotovorum subsp. brasiliensis
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The species of the genus Kalanchoe (Crassulaceae) are widely used in Brazil as a medicinal product to treat cough, boils, gastritis and other diseases. In this scenario stands out K. brasiliensis, popularly known as coirama or saião. This paper aims at the oral exposure of mice to a hydroalcoholic extract of leaves of Kalanchoe brasiliensis. The animals (total of 100) were divided into 12 groups (6 males and 6 females) for the acute assessment; and groups of 10 for subchronic evaluation. Test groups were treated with doses of 250 mg / kg, 500 mg / kg, 1000 mg / kg and 2000 mg / kg and the control group received 0.9% saline. The animals were observed for 14 days for acute evaluation and 30 days for subchronic evaluation, and in that period analyzed the appearance of clinical signs, changes in weight and consumption of water and food. After the observation period, histopathological analysis of the organs, biochemical serum and haematological parameters for the assessment of the subchronic groups were processed. Differences and changes in body weight were not observed among the groups, nor consumption of water and food, there were no deaths among the groups in the two types of assays. Histopathological analysis showed some alterations compatible with low acute hepatic toxicity. The results of blood glucose, triglycerides, ALT, urea and creatinine showed differences between the control group and the test concentrations studied (p <0.05), but these differences do not show relevant change in the clinical picture of animals. The results showed that the extract K. brasiliensis has low acute toxicity at the doses used and no toxicity when administered for 30 days. This highlights the importance of this species as future and promising candidate for phytotherapics, so has its pharmacological trials completed.
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The Bifibobacterium longum subsp. longum 35624™ strain (formerly named Bifidobacterium longum subsp. infantis) is a well described probiotic with clinical efficacy in Irritable Bowel Syndrome clinical trials and induces immunoregulatory effects in mice and in humans. This paper presents (a) the genome sequence of the organism allowing the assignment to its correct subspeciation longum; (b) a comparative genome assessment with other B. longum strains and (c) the molecular structure of the 35624 exopolysaccharide (EPS624). Comparative genome analysis of the 35624 strain with other B. longum strains determined that the sub-speciation of the strain is longum and revealed the presence of a 35624-specific gene cluster, predicted to encode the biosynthetic machinery for EPS624. Following isolation and acid treatment of the EPS, its chemical structure was determined using gas and liquid chromatography for sugar constituent and linkage analysis, electrospray and matrix assisted laser desorption ionization mass spectrometry for sequencing and NMR. The EPS consists of a branched hexasaccharide repeating unit containing two galactose and two glucose moieties, galacturonic acid and the unusual sugar 6-deoxy-L-talose. These data demonstrate that the B. longum 35624 strain has specific genetic features, one of which leads to the generation of a characteristic exopolysaccharide.
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This study describes further validation of a previously described Peptide-mediated magnetic separation (PMS)-Phage assay, and its application to test raw cows’ milk for presence of viable Mycobacterium avium subsp. paratuberculosis (MAP). The inclusivity and exclusivity of the PMS-phage assay were initially assessed, before the 50% limit of detection (LOD50) was determined and compared with those of PMS-qPCR (targeting both IS900 and f57) and PMS-culture. These methods were then applied in parallel to test 146 individual milk samples and 22 bulk tank milk samples from Johne’s affected herds. Viable MAP were detected by the PMS-phage assay in 31 (21.2%) of 146 individual milk samples (mean plaque count of 228.1 PFU/50 ml, range 6-948 PFU/50 ml), and 13 (59.1%) of 22 bulk tank milks (mean plaque count of 136.83 PFU/50 ml, range 18-695 PFU/50 ml). In contrast, only 7 (9.1%) of 77 individual milks and 10 (45.4%) of 22 bulk tank milks tested PMS-qPCR positive, and 17 (11.6%) of 146 individual milks and 11 (50%) of 22 bulk tank milks tested PMS-culture positive. The mean 50% limits of detection (LOD50) of the PMS-phage, PMS-IS900 qPCR and PMS-f57 qPCR assays, determined by testing MAP-spiked milk, were 0.93, 135.63 and 297.35 MAP CFU/50 ml milk, respectively. Collectively, these results demonstrate that, in our laboratory, the PMS-phage assay is a sensitive and specific method to quickly detect the presence of viable MAP cells in milk. However, due to its complicated, multi-step nature, the method would not be a suitable MAP screening method for the dairy industry.
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Fusarium wilt of banana, caused by the fungal pathogen Fusarium oxysporum f. sp. cubense (Foc), is one of the most destructive diseases of banana. A particularly virulent strain of the pathogen, tropical race 4 (TR4), presents an emerging threat to banana producing regions throughout the world. No commercially acceptable banana cultivar is resistant to TR4 and, as with all strains of the Fusarium wilt pathogen, there is no effective chemical control. Genetic resistance to TR4 has been observed in the diploid wild banana Musa acuminata subsp. malaccensis, which has consequently received attention as a potential source of Fusarium resistance genes. The aim of this research was to determine the pattern of inheritance of the resistance trait by screening plants for resistance to Foc subtropical race 4 (SR4) and TR4. Our results showed that the F1 progeny of self-fertilized malaccensis plants challenged in pot trials against SR4 (VCGs 0120, 0129, 01211) and TR4 (VCG 01213/16) segregated for resistance according to a Mendelian ratio of 3:1 which is consistent with a single dominant gene hypothesis.
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Knowledge of the environmental factors influence on the spatial-temporal variation of fishes is important to fisheries management and conservation. Thus, the aim of this work was to analyze the influence of the abiotical factors on the spatial-temporal distribution of Paralonchurus brasiliensis (Pisces, Sciaenidae) caught by-catch with the shrimp fishing of Ubatuba and Caraguatatuba regions, north coast of São Paulo State. The fishes were captured every month from January to December 2002. Samples were collected by otter trawl at 5, 10, 15, 20, 25, 30 and 35m depths. The temperatures (surface and bottom), salinities (surface and bottom), sediment features and organic matters were verified for each depth. During all period of the study 12.642 specimens of P. brasiliensis were captured at Ubatuba and 17.166 at Caraguatatuba, which totalized the biomass of 267 for the first and 339kg for the other region. The females outnumbered males in fish population. The greatest values of biomass and number of individuals were registered at the summer and autumn seasons, while the lowest values were observed at the winter and spring seasons. The greatest abundances were found from 15 to 25m depth. In this study, it was verified that P. brasiliensis is a coastal waters associate species. The spatialtemporal distribution of P. brasiliensis is affected by intrusion of SACW and depth for the coastal region and by depth and sediment in sheltered areas such as Caraguatatuba
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Ten growth or wood-quality traits were assessed in three nearby Corymbia citriodora subsp. variegata (CCV) open-pollinated family-within-provenance trials (18 provenances represented by a total of 374 families) to provide information for the development of a breeding program targeting both pulp and solid-wood products. Growth traits (diameter at breast high over bark [DBH], height and conical volume) were assessed at 3 and 7 years of age. Wood-quality traits (density [DEN], Kraft pulp yield [KPY], modulus of elasticity [MoE] and microfibril angle [MfA]) were predicted using near-infrared spectroscopy on wood samples collected from these trials when aged between 10 and 12 years. The high average KPY, DEN and MoE, and low average MfA observed indicates CCV is very suitable for both pulp and timber products. All traits were under moderate to strong genetic control. In across- trials analyses, high (>0.4) heritability estimates were observed for height, DEN, MoE and MfA, while moderate heritability estimates (0.24 to 0.34) were observed for DBH, volume and KPY. Most traits showed very low levels of genotype × site interaction. Estimated age–age genetic correlations for growth traits were strong at both the family (0.97) and provenance (0.99) levels. Relationships among traits (additive genetic correlation estimates) were favourable, with strong and positive estimates between growth traits (0.84 to 0.98), moderate and positive values between growth and wood-quality traits (0.32 to 0.68), moderate and positive between KPY and MoE (0.64), and high and positive between DEN and MoE (0.82). However, negative (but favourable) correlations were detected between MfA and all other evaluated traits (−0.31 to −0.96). The genetic correlation between the same trait expressed on two different sites, at family level, ranged from 0.24 to 0.42 for growth traits, and from 0.29 to 0.53 for wood traits. Therefore simultaneous genetic improvement of growth and wood property traits in CCV for the target environment in south-east Queensland should be possible, given the moderate to high estimates of heritability and favourable correlations amongst all traits studied, unless genotype × site interactions are greater than was evident. © 2016 NISC (Pty) Ltd
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O completo desenvolvimento larval de Notolopas brasiliensis é descrito, a partir de material criado em laboratório, com ênfase na morfologia externa de Majoidea e comparado aos demais gêneros de Pisidae. O desenvolvimento larval de N. brasiliensis consiste em dois estágios de zoea e um de megalopa. A duração media de cada estágio foi de 4.2 ± 1.0 dias para a Zoea I e 3.8 ± 0.7 dias para a Zoea II, a megalopa aparece entre 8.1 ± 0.4 dias após a eclosão. Os caracteres previamente utilizados para definir as formas larvais de Pisidae ou são simplesiomórficos ou altamente homoplásticos. Foi observado que não existe um conjunto de caracteres capazes de definir Pisidae até o presente.Contudo foi mostrado que uma combinação de caracteres pode ser utilizada para diferenciar Notolopas dos demais gêneros da família.
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Introducción: A mediados de los años 70’s del siglo pasado el descubrimiento de la tecnología del ADN recombinante marca el inicio de la era de la biotecnología moderna. La implementación de estas tecnologías permitió la utilización de organismos como sistemas de expresión que a lo largo de los años ha generado la producción de una gran variedad de productos biológicos. Dentro de estos sistemas Pichia pastoris es un sistema de expresión ampliamente utilizado debido a sus características tales como la producción de proteínas en grandes cantidades, la liberación de los productos al medio de cultivo, la obtención de productos complejos que requieren modificaciones postraduccionales típicas de los eucariotas o que contienen puentes disulfuro, entre otras. Nocardia brasiliensis es una bacteria parcialmente ácido-alcohol resistente la cual forma colonias granulares, con hifas aéreas escasas, sus colonias exhiben un color anaranjado pardo con bordes en blanco. N. brasiliensis es patógena para el ser humano y es el agente causal del actinomicetoma. El actinomicetoma es una enfermedad crónica generalmente localizada en las extremidades. Se caracteriza por ser un proceso lento de tumefacción con nódulos, abscesos y fístulas.La Superóxido Dismutasa (SOD) es una enzima reductora polimérica que cataliza la conversión del ión superóxido a peróxido de hidrógeno y oxígeno molecular. La SOD ha sido propuesta como un factor de virulencia de microorganismos patógenos, cuya acción consiste en bloquear los efectores oxidativos del estallido respiratorio iniciado por los fagocítos en el fagolisosoma. Este mecanismo ha sido descrito para bacterias de los géneros Mycobacterium, Rhodococcus y Nocardia. Objetivo: producir y caracterizar la Superóxido Dismutasa A (SODA) de Nocardia brasiliensis en Pichia pastoris. Metodología: se realizó el diseño de primers adicionando secuencias de sitios de corte para las enzimas XhoI y AvrII, así como una cola de histidinas en el extremo 5’ para la amplificación del gen sodA de N. brasiliensis a partir del ADN genómico de Nocardia brasiliensis. El amplicón se clonó en el vector de expresión pPIC9. Se llevó a cabo la transformación por electroporación de levaduras Pichia pastoris GS115. La producción de SOD se llevó a cabo en inducciones de 96 h con metanol como agente inductor. Los sobrenadantes se dializaron con membranas de celulosa. Los dializados se observaron por SDS-PAGE y western blot. Se analizó la actividad funcional de la enzima con el SOD Assay kit de Sigma Aldrich. Resultados: Por reacción en cadena de la polimerasa se obtuvo una secuencia de 625 pb correspondiente al gen sodA. El fragmento se ligó al vector de expresión pPIC9 y fue caracterizado con las enzimas de restricción XhoI y AvrII. Las cepas trasformadas de P. pastoris GS115 se caracterizaron con el gen aox1 obteniendo cepas Mut+ y Muts. Los análisis por SDSPAGE mostraron bandas no observadas en el control negativo de expresión mientras en los western blot solo una de las clonas mostró señal. Los análisis de actividad funcional sugieren inhibición de la reacción enzimática infiriendo presencia de la proteína SOD en el medio dializado. Conclusiones: Se logró la construcción del sistema de expresión Pichia pastoris con el casete de expresión de la SOD de N. brasiliensis. Así como la generación de cepas Mut+y Muts. En los ensayos de actividad funcional se observó inhibición de la reacción enzimática.
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299 p.
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Fungi of the genus Paracoccidioides are responsible for paracoccidioidomycosis. The occurrence of drug toxicity and relapse in this disease justify the development of new antifungal agents. Compounds extracted from fungal extract have showing antifungal activity. Extracts of 78 fungi isolated from rocks of the Atacama Desert were tested in a microdilution assay against Paracoccidioides brasiliensis Pb18. Approximately 18% (5) of the extracts showed minimum inhibitory concentration (MIC) values ≤ 125.0 μg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the best results, with an MIC of 15.6 μg/mL. This isolate was identified as Aspergillus felis (by macro and micromorphologies, and internal transcribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and was grown in five different culture media and extracted with various solvents to optimise its antifungal activity. Potato dextrose agar culture and dichloromethane extraction resulted in an MIC of 1.9 μg/mL against P. brasiliensis and did not show cytotoxicity at the concentrations tested in normal mammalian cell (Vero). This extract was subjected to bioassay-guided fractionation using analytical C18RP-high-performance liquid chromatography (HPLC) and an antifungal assay using P. brasiliensis. Analysis of the active fractions by HPLC-high resolution mass spectrometry allowed us to identify the antifungal agents present in the A. felis extracts cytochalasins. These results reveal the potential of A. felis as a producer of bioactive compounds with antifungal activity.
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Despite its ornamental value, some Melocactus species (Cactaceae) are threatened by several factors and only sexual propagation is possible. Thus, artificial seed banks are an appropriate method for their ex situ conservation. Suitable methods to germinate and to monitor viability are necessary for the seeds of these species. This work explored the use of tetrazolium test for monitoring seed viability of two Melocactus species. There was a correlation between the percentage of stained embryos, considering different cover area or tone stain, and the germination percentage. Unviable embryos did not stain. The embryos curved shape can explain the partial stain on the most of cases.
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Dittrichia viscosa subsp. viscosa (Compositae) is found on edges, wood clearings and in waste places of the Iberian Peninsula. Aerial parts of D. viscosa were collected at flowering phase in September-October 2001 around Lisbon, Portugal and the essential oils isolated by hydro-distillation for 4 h using a Clevenger-type apparatus. The oils were analyzed by gas chromatography and gas chromatography-mass spectrometry. Preliminary examination of the essential oils allowed the identification of 32 components. Only four components reached percentages over 5%: fokienol (11.8%), T-muurorol (7.9%), (E)-nerolidol (5.5%) and delta-cadinene (5.0%). The essential oils were tested against Helicobacterpylori and Listeria monocytogenes. Essential oils did not have antimicrobial activity against L. monocytogenes. The essential oil at 0.88 to 22.22 mu g.ml(-1) did not inhibit the growth of H. pylori, affected the growth slightly at 44.40 mu g.ml(-1), and completely inhibited the growth at 88.80 to 133.20 mu g.ml(-1) Results show that use of D. viscosa essential oil in the treatment of gastric disorders caused by H. pylori can be effective.
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Objetivo: Investigar el papel de la angiogénesis durante el desarrollo del actinomicetoma y sobre el actinomicetoma establecido en un modelo experimental. Material y métodos: se determinó si el fenofibrato inhibe el crecimiento de la bacteria mediante la técnica de microdilución en placa. Se administró una suspensión de fenofibrato vía orogástrica cada 24 h durante el establecimiento del actinomicetoma y sobre el actinomicetoma establecido en ratones BALB/c infectados con la cepa N. brasiliensis HUJEG-1 (ATCC 700358). El tratamiento en ambos casos tuvo una duración de 45 días, tiempo en el que se evaluaron las diferencias en inflamación y la evolución clínica de las lesiones, empleando un vernier y la ecuación elipsoidea. También se realizó el análisis histológico en el sitio de la infección mediante tinciones con hematoxilina y eosina. El proceso de angiogénesis fue evaluado a diferentes tiempos en la administración del tratamiento mediante inmunohistoquímica, buscando como marcadores de vasos sanguíneos las moléculas VEGF, eNOS, y LYVE-1, este último como un marcador indirecto del proceso angiogénico. Resultados: se comprobó que el fenofibrato no inhibe el crecimiento de la bacteria a la concentración correspondiente a EC50 en ratones. Las lesiones características de la enfermedad se desarrollaron en un menor número de ratones que recibieron el tratamiento de fenofibrato, durante el establecimiento del actinomicetoma y sobre el actinomicetoma establecido. Además, se observó una disminución en las medidas de inflamación y en la aparición de lesiones histológicas, así como una disminución en el número de vasos sanguíneos en los sitios de la infección. Conclusiones: La angiogénesis contribuye a la patogenia del actinomicetoma por N. brasiliensis; la disminución de la formación de vasos sanguíneos por el tratamiento con fenofibrato limita el grado de la lesión.
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2016
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Em lutas entre peixes residentes e intrusos, residentes geralmente vencem, provavelmente porque valorizam o território mais do que os intrusos. Nós aventamos a hipótese de que ambientes enriquecidos aumentam o valor da área em disputa, levando os residentes a defenderem mais violentamente ambientes enriquecidos de recursos do que ambientes empobrecidos, pois possuiriam mais motivação para mantê-lo. No entanto, no presente estudo, ao testarmos as interações entre intrusos e residentes em acarás, Geophagus brasiliensis, observamos que o enriquecimento ambiental reduz a agressividade e pode levar a cohabitação entre os peixes, sem luta. Adicionalmente, em nossos experimentos, o efeito da residência prévia ocorreu independente da condição de enriquecimento. A diminuição das interações entre os peixes e, consequentemente, a diminuição do nível de agressividade é aqui atribuída aos efeitos da diminuição da visibilidade entre os peixes devido ao aumento de complexidade do ambiente.