20 research outputs found
Database Survey of Anti-Inflammatory Plants in South America: A Review
Inflammation is a complex event linked to tissue damage whether by bacteria, physical trauma, chemical, heat or any other phenomenon. This physiological response is coordinated largely by a variety of chemical mediators that are released from the epithelium, the immunocytes and nerves of the lamina propria. However, if the factor that triggers the inflammation persists, the inflammation can become relentless, leading to an intensification of the lesion. The present work is a literature survey of plant extracts from the South American continent that have been reported to show anti-inflammatory activity. This review refers to 63 bacterial families of which the following stood out: Asteraceae, Fabaceae, Euphorbiaceae, Apocynaceae and Celastraceae, with their countries, parts used, types of extract used, model bioassays, organisms tested and their activity
TeorÃa de los mercados eficientes : una revisión de la eficiencia del mercado : estudio de la literatura teórica y empÃrica de la teorÃa de los mercados eficientes y de la eficiencia de mercado en su forma débil
Fil: Nadinic, Vladimir. Universidad de San Andrés. Escuela de Negocios; Argentina."Este estudio se centra en la revisión de literatura teórica y empÃrica de La TeorÃa
de los Mercados Eficientes. Se presentan los fundamentos teóricos y empÃricos
sobre los cuales se basa la teorÃa, y se presenta evidencia que respalda la
eficiencia de los mercados, asà como aquella que intenta refutarla.
A su vez, se realiza un estudio empÃrico con el objetivo de encontrar evidencia a
favor o en contra de la forma débil de eficiencia de los mercados. En este estudio
se busca encontrar un patrón en el precio de las acciones, teniendo como
resultado que no se puede encontrar el mismo, apoyando la eficiencia de los
mercados.""Palabas clave: Eficiencia, racionalidad, rendimiento, portafolio, TeorÃa de los
Mercados Eficientes"Fernández Molero, Dieg
Métodos de integración geométrica. Análisis y algoritmos numéricos
El marco teórico donde se desarrolla la genésis de estos métodos son los grupos y álgebras de Lie. Estas estructuras algebraicas, ampliamente estudiadas, dan el entorno propicio para la construcción de nuevos algoritmos simplécticos.
A lo largo de este trabajo, se presentan diversos métodos integración geométrica, algunos ya clásicos, como los basados en la expansión de Magnus, y otros nuevos como el método de Splitting de paso fijo y h-adaptativo, o el método de Voslamber. También se construye un nuevo procedimiento recursivo eficiente, para obtener en forma sistemática y de cantidad arbitraria, los términos necesarios para la fórmula de Zassenhaus, asà como la variante continua de este, conocida como fórmula de Wilcox. Para cada método presentado se analizan sus principales caracterÃsticas, mostrando sus resultados a situaciones de interés, ya sea en la ciencia aplicada o bien como instancias que los pongan a prueba o permitan hacer comparaciones, en especial sobre su precisión y uso de recursos como tiempo de CPU y memoria de computación requeridos, en versiones implementadas en software como, Mathematica o Matlab
FITOCOSMÉTICA SUSTENTABLE. ALTERNATIVA INNOVADORA PARA EL DESARROLLO DE LA REGIÓN
La Facultad fue sede del I Simposio Internacional de Fitocosmética Sustentable abriendo nuevas perspectivas para la investigación, innovación e interacción entre los diferentes sectores
Aeromonas spp. isolated in Cearà - Brazil : genotypic detection of virulence factors and susceptibility in vitro antimicrobial.
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorEspÃcies do gÃnero Aeromonas, encontradas com frequÃncia em ambientes aquÃticos, sÃo importantes patÃgenos humanos. Este estudo teve como objetivo geral isolar cepas clÃnicas e ambientais de Aeromonas spp., assim como, investigar a presenÃa de genes de virulÃncia e avaliar a sensibilidade a antimicrobianos in vitro, bem como, o mecanismo de resistÃncia. As amostras clÃnicas e ambientais foram identificadas por meio de testes bioquÃmicos e metodologia automatizada Vitek2Â (bioMeriÃux). A detecÃÃo de genes de virulÃncia para enterotoxina citotÃxica (act), hemolisina (asa1) e sistema de secreÃÃo III (ascV) foi feita por PCR simples. A sensibilidade aos antimicrobianos seguiu recomendaÃÃes dos documentos M7-A9 e M45-A2 do CLSI. A caracterizaÃÃo do mecanismo de resistÃncia foi realizada mediante testes fenotÃpicos para detecÃÃo de Ã-lactamases. Dos isolados clÃnicos foram identificados dezenove A. hydrophila, trÃs A. veronii bv. sobria e uma A. caviae. As 35 cepas ambientais foram identificadas como A. hydrophila (n=11), A. veronii bv. sobria (n=22), A. veronii bv. veronii (n=1) e A. caviae (n=1). Em relaÃÃo aos genes de virulÃncia das cepas clÃnicas, foram detectados os genes act, asa1 e ascV nas proporÃÃes 69,5; 8,6 e 34,7%, respectivamente. Enquanto nas cepas ambientais foram encontrados os percentuais de 51,4; 45,7 e 54,2%, respectivamente. Observou-se resistÃncia a piperacilina-tazobactam e a amoxicilina-clavulanato, em 3 e 15 cepas clÃnicas, respectivamente. Ademais, houve resistÃncia a ceftazidima, meropenem, imipenem, ciprofloxacina e trimetoprim-sulfametoxazol, com uma cepa resistente a cada antimicrobiano. Quanto Ãs cepas ambientais, detectou-se resistÃncia somente a piperacilina-tazobactam e amoxicilina-clavulanato em 1 e 17 cepas, respectivamente. Em relaÃÃo a detecÃÃo de Ã-lactamases, foi detectada AmpC em doze cepas clÃnicas e sete ambientais. Em suma, apesar de ter sido obtido um maior percentual de resistÃncia em cepas de origem humana, as cepas ambientais tambÃm apresentaram este fenÃmeno e em ambas foram detectados genes de virulÃncia. Portanto, Ã importante realizar o monitoramento do potencial patogÃnico e sensibilidade de isolados ambientais.Aeromonas spp., frequently found in aquatic environments, are important human pathogens. This study had the main objectives of isolating clinical and environmental strains of Aeromonas spp. and investigating the presence of virulence genes, antimicrobial susceptibility in vitro and resistance mechanism. Clinical and environmental samples were identified by biochemical tests and the automated Vitek2Â (bioMeriÃux) method. The virulence genes cytotoxic enterotoxin (act), haemolysin (asa1) and type III secretion system (ascV) were detected by simple PCR. The antimicrobial susceptibility was determined according to the recommendations of M7-A9 and M45-A2 do CLSI. The characterization of resistance mechanism was performed by detection of Ã-lactamases phenotypic tests. From the clinical isolates, 19 A. hydrophila, 3 A. veronii bv. sobria and 1 A. caviae were identified The 35 environmental strains were identified as A. hydrophila (n= 11), A. veronii bv. sobria (n= 22), A. veronii bv. veronii (n= 1) and A. caviae (n= 1). Regarding the virulence genes of clinical strains, the act, asa1 and ascV genes were detected in the proportions 69.5, 8.6 and 34.7%, respectively. The respective percentages for the environmental strains were 51.4, 45.7% and 54.2%. Resistance was observed to piperacillin-tazobactam and amoxicillin-clavulanate in 3 and 15 clinical strains, respectively. Moreover, there was resistance to ceftazidime, meropenem, imipenem, ciprofloxacin and trimethoprim-sulfamethoxazole, with one strain resistant to each antimicrobial agent. As for the environmental strains, resistance was detected only to piperacillin-tazobactam and amoxicillin-clavulanate and, in 1 and 17 strains, respectively. Regarding the detection of Ãâlactamases, AmpC was detected in clinical (n= 12) and environmental strains (n= 7). In short, despite having observing higher percentage of resistance in strains of human origin, environmental strains also showed this phenomenon and virulence genes were detected in both strains. Thus, it is important to monitor the antimicrobial susceptibility and pathogenic potential of the environmental isolates
Computer Physics Communications Efficient computation of the Zassenhaus formula
a b s t r a c t A new recursive procedure to compute the Zassenhaus formula up to high order is presented, providing each exponent in the factorization directly as a linear combination of independent commutators and thus containing the minimum number of terms. The recursion can be easily implemented in a symbolic algebra package and requires much less computational effort, both in time and memory resources, than previous algorithms. In addition, by bounding appropriately each term in the recursion, it is possible to get a larger convergence domain of the Zassenhaus formula when it is formulated in a Banach algebra
Purpurenol, a Highly Oxygenated Coumarin From Pterocaulon-purpurascens
A new 5,6,7,8-tetraoxygenated coumarin, named purpurenol, was isolated from aerial parts of Pterocaulon purpurascens. Its structure was elucidated on the basis of the spectral data and was confirmed by X-ray analysis
Purpurasol, a highly oxygenated coumarin from Pterocaulon purpurascens
A new 6,7,8-trioxygenated coumarin, named purpurasol, was isolated from the aerial parts of Pterocaulon purpurascens. The structural elucidation was performed by spectroscopic analysis including 500 MHz H-1 NMR, C-13 NMR, IR and EI mass spectral data
5-(3-methy-2-butenyloxy)-6,7-methylenedioxy-coumarin, a 5,6,7-trioxygenated Coumarin From Pterocaulon Virgatum
The coumarin 1 [5-(3-methyl-2-butenyloxy)-6,7-methylenedioxycoumarin] and the recently reported 5-methoxy-6,7-methylenedioxycoumarin, have been isolated from a petroleum ether extract of Pterocaulon virgatum. The structure of 1 was determined on the basis of X-ray crystallographic analysis and spectroscopic data