RESUMO A atividade antibacteriana do extrato alcaloidal das folhas de Croton bonplandianum Baill., além dos principais compostos isolados, esparsiflorina e crotsparina, foi testada contra Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae e Pseudomonas aeruginosa. Foi utilizado o método de microdiluição em placa empregando resazurina como indicador da viabilidade celular. Os compostos isolados foram identificados por técnicas espectroscópicas, principalmente RMN 1D e 2D. O extrato alcaloidal foi ativo principalmente contra S. aureus e P. aeruginosa. Crotsparina mostrou-se inativa contra todos os micro-organismos testados, enquanto esparsiflorina apresentou atividade moderada, a qual foi similar à do extrato bruto. Pseudomonas aeruginosa foi a mais sensível das bactérias testadas, com CIM de 0,141 mg/mL. Os resultados sugerem que a atividade do extrato pode ser devida em grande medida pela presença de esparsiflorina. Apesar de a CIM da esparsiflorina não ter se aproximado daquela apresentada pelos agentes antimicrobianos em uso clínico, tal composto ainda pode compor um protótipo interessante para o desenvolvimento de novas substâncias antibacterianas.

ABSTRACT The antibacterial activity of the alkaloid extract from the leaves of Croton bonplandianum Baill. and its main compounds, sparsiflorine and crotsparine, was tested against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa by the resazurin microtitre-plate method. Pure compounds were identified by spectroscopic techniques, mainly 1D and 2D NMR. The alkaloid extract showed activity particularly against the S. aureus and P. aeruginosa. Regarding the pure compounds, the crotsparine was inactive against the microorganisms assayed, whereas the sparsiflorine indicated a moderate activity similar to the alkaloid extract. The Pseudomonas aeruginosa was the most sensitive of the tested microorganisms with MIC of 0.141 mg/mL. The results suggest that the activity of the extract may be credited mainly to the presence of the sparsiflorine. Although the activity of the sparsiflorine does not get close to the antimicrobial drugs in clinical use, it still could be a lead compound for the development of new antibacterial substances.

Thirty five percent of cancer cases are associated with a bad diet. Studies performed in the region show a high frequency of bad alimentary habits. The alimentary behavior of the Paraguayan population has not been studied systematically yet, although it is well known that our population prefers red meats, barbecues and fried foods and eat relatively low amounts of fruits and vegetables. This study was developed to determine the frequency of alimentary habits associated to the risk of developing cancer in public servants and investigate the possible association between those habits and sex. This is a cross-sectional observational descriptive study that applied an alimentary questionnaire to interview 150 public servants between April and May 2010; subjects were randomly selected from those working at eight public offices previously chosen by convenience. The weekly and daily frequencies of consumption of different food categories were recorded and the subjects were grouped in levels according to the recommendations of international organizations. The sample was made up of 72% men with an average age 35 years. Fifty two percent of the respondents declared daily eating of vegetables, but only 9% reached the optimum level. The consumption of such foods was low or absent in 60% of the individuals, and 64% consumed red meats with very high frequency. In the analyzed sample, there was a high frequency of inappropriate alimentary habits and a low consumption of healthy food associated with cancer prevention, which reveals the necessity of implementing educative programs focused on this issue.

El 35% de los casos de cáncer está asociado a una mala alimentación. Estudios realizados en la región muestran una elevada frecuencia de malos hábitos alimentarios. El comportamiento alimentario de la población paraguaya aun no ha sido estudiado de manera sistemática, aunque es de público conocimiento el gusto de nuestra población por las carnes rojas, el asado y los alimentos fritos, así como el bajo consumo relativo de frutas y hortalizas. Este trabajo se realizó para determinar la frecuencia de hábitos alimentarios vinculados al riesgo de desarrollar cáncer en funcionarios públicos de Asunción, e indagar la posible asociación entre dichos hábitos y el sexo. Es un estudio observacional descriptivo, transversal, en el que utilizando una encuesta alimentaria se entrevistaron, entre abril y mayo de 2010, 150 funcionarios seleccionados aleatoriamente de ocho oficinas públicas, previamente seleccionadas por conveniencia. Se registró la frecuencia semanal y diaria de consumo de diferentes categorías de alimentos y los individuos fueron agrupados en niveles según adecuación a las recomendaciones de organismos internacionales. La muestra estuvo constituida por 72% de varones, siendo la media de edad 35 años. El 52% declaró consumir hortalizas diariamente, alcanzando el consumo óptimo solo el 9%. Se encontró un consumo bajo o nulo de estos alimentos en el 60 % de los encuestados, y también se observó que el 64% consumía en exceso carnes rojas. En la muestra analizada hay elevada frecuencia de hábitos alimentarios inapropiados y bajo consumo de alimentos saludables vinculados a la prevención del cáncer, lo que revela la necesidad de implementar programas específicos de educación nutricional.

ABSTRACT A comparative study was performed to evaluate the in vitro antihelmintic activity of different formulations extracted from the Stevia rebaudiana Bertoni (SRB) plant, and the stevioside by the technique of motility and survival soil worms, a free life nematode used as a biologic model, according to the measurement of the variable time of survival or death expressed in minutes. The SRB's formulations were: aqueous solution, 1% and 10% ethanol extracts of the 10% aqueous extract. The stevioside (powder) was diluted to use at 0.5mg % and 0.5g %. Commercial formulations of 1% and 10% albendazole, 10% mebendazole 10% and a 5% saline solution were used as positive and negative controls respectively. The qualitative evaluation of the assay showed evident antihelmintic activity of SRB in the 1% and 10% alcoholic extract as well as in the 10% aqueous extract. Mebendazole also showed activity but in lower proportion and it alto took ten times more to be evident.

RESUMEN Se realizó un estudio comparativo para evaluar la actividad anti helmíntica in vitro de varias formulaciones de la planta Stevia rebaudiana Bertoni (SRB), ka'á he'ê, y el steviósido según la técnica de motilidad y supervivencia de la lombriz de la tierra utilizada como modelo biológico, nematodo de vida libre; según la medida de la variable tiempo de supervivencia o muerte expresada en minutos. Las formulaciones de las Stevia rebaudiana Bertoni (SRB) fueron: en solución acuosa, del extracto etanólico al 1 y 10% del extracto acuoso al 10%. El steviósido (polvo) en solución utilizado fue al 0,5 mg% y 0,5 g%. Los formulados comerciales en solución: Albendazol al 1 y 10%; Mebendazol al 10% como controles positivos y como control negativo: Solución de suero fisiológico al 5%. La evaluación cualitativa del ensayo demostró actividad antihelmíntica evidente de la SRB en solución del extracto alcohólico el 1% y al 10% y la solución del extracto acuoso al 10% así como el Mebendazol pero éste en mucho menor proporción y en 10 veces más tiempo.

An investigation was carried out in La Palma town, Pinar del Rio, with the objective of evaluating the role played by the formal production and improved seed distribution system of main grains: bean (Phaseolus vulgaris, L.), maize (Zea mays, L.) and rice (Oryza sativus, L.), to support town´s food security. Thus, historical records of grain seed entry to the urban farm within the latest seven years were analyzed concerning the varieties introduced, prices and quantities sold. For data analysis, tendency performance graphs were plotted and correlations analyses were performed. It was recorded that agriculture of main grains from La Palma is carried out over 94.8 % with farm-produced seeds whereas the formal seed system has given a poor contribution to town´s food security, providing only 4.08 % of improved seed to maize, 5.20 % to bean and 0 % to rice.

Se llevó a cabo una investigación en el municipio La Palma, Pinar del Río, con el objetivo de valorar el papel que ha jugado el sistema formal de producción y distribución de semillas mejoradas de granos principales: frijol (Phaseolus vulgaris, L.), maíz (Zea mays, L.) y arroz (Oryza sativus, L.), en apoyo a la seguridad alimentaria de este municipio. Para ello, se analizaron los registros históricos de la entrada de semillas de estos granos a través de la granja urbana durante los últimos siete años, referentes a variedades introducidas, precios y cantidades vendidas. Para el análisis de los datos, se plotearon gráficos de comportamiento tendencial y se realizaron análisis de correlación. Se encontró que la agricultura de los granos principales de La Palma se lleva a cabo en más de un 94.8 % con semillas de producción campesina y que el sistema formal de semillas ha tenido un aporte pobre a la seguridad alimentaria de este municipio, contribuyendo con un 4.08 % de semilla mejorada para el cultivo del maíz, 5.20 % para el del frijol y 0 % para el arroz.

OBJETIVO: Propor uma metodologia para caracterizar proficiência na pesquisa de bacilos álcool-ácido resistentes (BAAR) em baciloscopias de escarro para diagnóstico da tuberculose, assim como determinar o número necessário de baciloscopias para estabelecer essa proficiência, a qualidade da transcrição dos resultados, as causas das discordâncias nas leituras (leitor e/ou microscópio utilizado) e o critério de classificação de resultados baciloscópicos que causa maior dificuldade na caracterização de proficiência. MÉTODOS: Quatrocentas baciloscopias de escarro para diagnóstico da tuberculose foram analisadas, mediante leituras duplo-cegas, por seis profissionais que usualmente efetuam leitura/supervisão de baciloscopias realizadas na rede básica de saúde. A amostragem foi determinada visando a obter, no mínimo, 90% de concordância nas leituras duplo-cegas, erro alfa de 5% e precisão de 3%. Os resultados foram analisados mediante concordância observada/índice kappa. RESULTADOS: Constataram-se 13 erros de transcrição dos resultados (0,27%). A concordância aumentou quando as três categorias distintas de resultados baciloscópicos positivos (BAAR+, BAAR++ e BAAR+++) foram agrupadas ou foram excluídos da análise os exames com resultados inconclusivos. A quantificação da carga bacilar foi o critério de classificação que causou maior dificuldade para caracterização de proficiência. A qualidade do microscópio utilizado foi importante para o aumento da concordância. A estabilização dos valores de concordância somente foi obtida a partir da leitura de 75 baciloscopias. CONCLUSÕES: O uso de leituras baciloscópicas duplo-cegas utilizando-se painel composto por 75 lâminas (36 negativas, 4 inconclusivas e 35 positivas) mostra-se adequado para caracterizar a proficiência em baciloscopia para diagnóstico da tuberculose quando essa proficiência pretende reproduzir a rotina laboratorial.

OBJECTIVE: To propose a methodology for characterizing proficiency in sputum smear microscopy for acid-fast bacilli (AFB) in the diagnosis of tuberculosis and to determine the number of microscopies necessary to establish this proficiency, as well as the quality of the transcription of results, the causes of the discrepancies in the readings (rater or microscope used), and the criterion for classification of microscopy results that poses the most difficulty in characterizing proficiency. METHODS: Four hundred sputum smear microscopies for the diagnosis of tuberculosis were analyzed through double-blind readings by six professionals who usually read/supervise microscopies performed in public health care facilities. The sample was stratified to obtain, at least, a reliability of 90% in the double-blind readings, an alpha error of 5%, and a precision of 3%. The results were analyzed using observed reliability and the kappa index. RESULTS: Thirteen errors (0.27%) were found in the transcription of results. Reliability increased when the three distinct categories of positive results (AFB+, AFB++, and AFB+++) were grouped or when inconclusive results were excluded from the analysis. The quantification of the bacterial load was the classification criterion that posed the most difficulty in establishing proficiency. Using higher quality microscopes increased reliability. Reliability values stabilized only from the reading of 75 microscopies onward. CONCLUSIONS: Double-blind sputum smear microscopy readings using a panel containing 75 slides (36 negative, 4 inconclusive, and 35 positive) proved to be appropriate for characterizing proficiency in sputum smear microscopy for the diagnosis of tuberculosis when such proficiency is intended to reproduce laboratory routine.

This research work was aimed at understanding the principles regulating farmers’ maize varietal selection and adoption in poorly-benefited agricultural systems by the formal seed system. The experiment was conducted in a grower’s farm from La Palma, Pinar del Río. Free selection of 55 maize genotypes from six provinces of the country, both of the formal and informal sectors, was available. Then, 70 kg.ha-1 of a mixture of 20 % NPK and 80 % organic manure were fertilized. Irrigation was applied twice, so that the field remained without weed. 83 farmers participating in the selection process were surveyed, in order to gather some information about their most important selection criteria and, at the same time, evaluate 20 descriptors, such as yield and its components, tolerance to weevil and plant height. As a complement of all data recorded, individual interviews were performed to farm selectors, to deepen on their knowledge background about the selection process. For data processing, the analysis of proportions, Kendall’s non-parametric correlation and graph representations were used. Farmers select their own varieties by ‘practical correlation’, with the help of qualitative characters as the biological markers of their main objective and insect resistance after harvest. The ‘ear shape’ character is the most important selection criteria in this maize production system

El presente trabajo se realizó con el objetivo de comprender los principios que regulan la selección y adopción de variedades de maíz por campesinos, en sistemas agrícolas poco beneficiados por el sistema formal de semillas. La experiencia se llevó a cabo en la finca de un productor de La Palma, Pinar del Río. Se facilitó la libre selección de 55 materiales de maíz de seis provincias del país, procedentes tanto del sector formal como del informal. La fertilización fue de 70 kg.ha-1 de una mezcla compuesta por el 20 % de NPK y 80 % de abonos orgánicos. Los riegos se realizaron en dos momentos y el experimento se mantuvo libre de plantas fuera de lugar. Se aplicó una encuesta a los 83 campesinos participantes en el proceso de selección, para colectar información acerca de los criterios más importantes para ellos y, al mismo tiempo, se evaluaron 20 descriptores, entre los que se encontraban el rendimiento y sus componentes, la susceptibilidad al gorgojo y altura de la planta. Como complemento a los datos registrados, se realizaron entrevistas individuales a campesinos seleccionadores, para profundizar en las bases del conocimiento del proceso de selección practicado. Para el procesamiento de los datos se utilizó el análisis de proporciones, la correlación no paramétrica (Kendall) y representaciones gráficas. Se encontró que los campesinos eligen sus variedades por ‘correlación práctica’, auxiliándose de caracteres cualitativos, como los marcadores biológicos de su objetivo principal y la resistencia a los insectos en poscosecha. El carácter “forma de la mazorca” es el criterio de selección más importante en este sistema de producción de maíz

In this paper we describe and evaluate the main features of the uRT51 processor. The uRT51 processor was designed for embedded real-time control applications. It is a processor architecture that incorporates the specific functions of a real-time system in hardware. It was described using synthesizable VHDL and it was implemented on FPGA devices. We describe how the uRT51 processor supports time, events, task and priorities. The performance of the uRT51 processor is evaluated using a control application as a case study. The experiments show that the uRT51 processor scheduling features outperform the ones obtained using a traditional RTOS-based real-time system.