Introducción: El parásito Ascaris lumbricoides es el más grande de los nemátodos que parasita el intestino humano. En Venezuela, la infección por Ascaris lumbricoides es la geohelmintiasis de mayor importancia en zonas rurales, por su alta frecuencia y morbilidad. La infección estimula una respuesta de anticuerpos IgA, sin embargo se conoce poco sobre las proteínas responsables de la respuesta para este isotipo. La identificación de estas proteínas podría ayudar al diseño de pruebas para el diagnóstico y la detección en el medio ambiente o en individuos expuestos a este parásito. Nuestro trabajo se basó en identificar proteínas antigénicas en extractos y fracciones de A. lumbricoides para la respuesta especifica IgA en el suero de niños infectados. Materiales y métodos: Fueron evaluados 85 sueros de niños de ambos sexo entre 3 y 14 años de edad, de comunidades rurales del Estado Miranda. Los niños fueron clasificados según el resultado coprológico en tres grupos, Ascaris positivos en heces; Ascaris negativos con otras parasitosis y un grupo libre de parásitos en heces. Las proteínas fueron identificadas por Western Blot y el nivel de anticuerpos IgA medidos por ELISA. Resultados: Se detectaron en el extracto de A. lumbricoides un mínimo de 17 proteínas con pesos moleculares de entre 26 y 205 KDa aproximadamente, siendo reconocidas por el suero de los niños infectados proteínas de 205, 148, 95, 75 y 45KDa. Conclusiones: El presente trabajo permitió medir los niveles de anticuerpos específicos IgA anti-Ascaris e identificar las proteínas responsables de la respuesta IgA.

Introduction: The parasite Ascaris lumbricoides is the largest nematode parasitizing the human intestine. In Venezuela, infection with Ascaris lumbricoides is the most important STH in rural areas, because of its high frequency and morbidity. Infection stimulates an antibody IgA response, however little is known about the proteins responsible for this isotype. The identification of these proteins could aid the design of tests for the diagnosis and detection in the environment or individuals exposed to this parasite. Our work was based on the identification of antigenic proteins in extracts and fractions of A. lumbricoides for specifi c IgA antibody response in serum of infected children. Materials and Methods: A total of 85 sera from children (boys and girls) between 3 and 14 years old, from rural communities in Miranda State. Children were classifi ed according to the stool results in three groups, Ascaris positive in stool; negative for Ascaris, but with other parasites and a group no parasites in feces. Proteins were detected by Western blotting and the IgA antibody levels measured by ELISA. Results: We detected in the extract of A. lumbricoides at least 17 proteins with molecular weights of between 26 and 205 kDa and were recognized by the sera of infected children, proteins of 205, 148, 95, 75 and 45kDa children. Conclusions: This study allowed us to measure the levels of specific IgA anti-Ascaris and identify the proteins responsible of this response.

Clove essential oil, used as an antiseptic in oral infections, inhibits Gram-negative and Gram-positive bacteria as well as yeast. The influence of clove essential oil concentration, temperature and organic matter, in the antimicrobial activity of clove essential oil, was studied in this paper, through the determination of bacterial death kinetics. Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were the microorganisms selected for a biological test. To determine the temperature effect, they were assayed at 21° and 37° C. The concentration coefficient was determined with 0.4%, and 0.2% of essential oil. The influence of the presence of organic matter was determined with 0.4% of essential oil. The results obtained demonstrated that Escherichia coli were more sensitive even though the essential oil exerted a satisfactory action in three cases. In the three microbial species, 0.4% of essential oil at 21º C have reduced the bacterial population in 5 logarithmic orders. Organic matter reduces the antibacterial activity even though the bactericide efficacy was not lost. Clove essential oil can be considered as a potential antimicrobial agent for external use

According to a synecologic characterization of the vegetation in a near area to El Salto, Durango, Mexico, are reported eight vegetation units. This was done according to semi realistic profiles and Dansereau diagrams that describe the physiognomic characteristics of each unit. Also was elaborated a floristic list. The units were ordinated and classified numerically, showing that the latitudinal and topographic gradients influence the floristic composition across the study area.

De acuerdo a la caracterización sinecológica de la vegetación en el área aledaña de El Salto, Durango. Se reportan ocho unidades de vegetación y mediante perfil semirrealista y danserogramas se describen las características fisonómicas de cada una, así como la lista florística, estableciendo su ordenación y clasificación numérica, mostrando que los gradientes latitudinales y topográficos influyen en la composición florística del área de estudio.

Os hospitais utilizam uma grande quantidade de desinfetantes para eliminar microorganismos tanto da pele humana como de superfícies inanimadas. Após sua utilização, esses produtos podem chegar ao esgoto em quantidades residuais. A pressão seletiva exercida pelos antimicrobianos nos efluentes hospitalares propicia a disseminação de linhagens resistentes. Além dos antibióticos, os desinfetantes podem atuar como agentes seletivos de linhagens resistentes aos antimicrobianos. Este trabalho teve como objetivo o estudo do perfil da resistência aos desinfetantes das bactérias lançadas na rede de esgoto pelo efluente hospitalar. Na caracterização microbiológica do efluente do Hospital de Clínicas Buenos Aires, determinou-se a concentração de bactérias heterotróficas, bactérias indicadoras fecais, Pseudomonas sp. e Staphylococcus sp. presentes. A resistência aos desinfetantes empregados no hospital, glutaraldeído, iodo povidona, e clorexidina foi então avaliada. Verificou-se a existência de bactérias resistentes à clorexidina em número variando de 10³ a 10(6) bactérias/100 mL e de bactérias resistentes a outros desinfetantes em uma faixa de variação de 10³ a 10(4) bactérias/100 mL. Bactérias dos gêneros Staphylococcus e Bacillus, e da família Enterobacteriaceae, envolvidas em infecções hospitalares, apresentaram resistência aos desinfetantes testados. Estes resultados indicam que as águas residuárias de hospitais desempenham um papel de grande relevância na disseminação de linhagens bacterianas resistentes aos desinfetantes no meio aquático.

Large quantities of disinfectants are used in hospitals, externally on human skin or to eliminate microorganisms from inanimate objects. After use, residual quantities of these products reach the wastewater, exposing the bacteria that survive in hospital wastewaters to a wide range of biocides that could act as a selective pressure for the development of resistance. Increasing attention has been directed recently to the resistance of bacteria to disinfectants. The aim of this paper was to determine the disinfectant bacterial resistance pattern of the microflora released to the urban sewer system by hospital effluents. The characterization of the waste water microflora was performed by determination of the CFU of heterotrophic bacteria, fecal indicator bacteria, Pseudomonas sp. and Staphylococcus sp., in a Buenos Aires hospital effluent. The bacterial resistance to the disinfectants more frequently used in the hospital practice, glutaraldehyde, chlorhexidine and povidone-iodine, was then evaluated. Disinfectant resistant bacterial strains were isolated and typified. Between 10³ and 10(6) chlorexidine resistant bacteria/100 mL were isolated from the samples. Bacteria resistant to other disinfectants ranged between 10³ and 10(4) /100 mL. The bacterial population resistant to desinfectants to was mainly composed by Enterobacteriaceae, Staphylococcus spp, and Bacillus spp, which are highly associated to nosocomial infections. The results obtained show that the hospital effluents are of importance in the bacterial resistance selection process, particularly in the case of disinfectants.

The aim of the research was to evaluate under greenhouse conditions, the effect of two different levels of soil humidity (20-25% and 50-55%) on the development of Angiosorus solani artificially inoculated in the soil. The two potato (Solanum tuberosum) varieties, Mirka and Cardinal, were considered as resistant and susceptible to the diseasem, respectively. Water in the soil was adjusted periodically to maintain the soil humidity levels constant during the research. A completely randomized experimental design with five replications and one plant per replication was used. Emergence, days between emergence and harvest, disease symptoms, weight and number of tubers at harvest were evaluated. Results were submitted to variance analysis and Fisher’s mean difference test. Results indicated that there were no significant differences (P <= 0.05) between treatments for emergence; on average tubers emerged at 12 days after planting. The period from emergence to harvest showed significant differences (P <= 0.05) between humidity levels with the longer period for the higher humidity level (50-55%). The disease was present only in treatments inoculated with A. solani and mainly in the Cardinal variety. Only one Mirka plant developed disease symptoms. It was not observed effect of soil humidity on the development of the disease

El experimento tuvo como objetivo estudiar bajo condiciones de invernadero, el efecto de dos niveles de humedad en el suelo (20-25% y 50-55%), en el desarrollo del hongo Angiosorus solani inoculado artificialmente al suelo, donde se plantaron dos variedades de papa (Solanum tuberosum) Mirka y Cardinal, consideradas como resistente y susceptible a la enfermedad, respectivamente. Los porcentajes de humedad en el suelo se mantuvieron durante todo el período que duró el ensayo y la reposición de agua se realizó periódicamente en base a diferencias de peso. Se utilizó un diseño experimental completamente al azar con cinco repeticiones y una planta por repetición. Las variables medidas fueron emergencia, días de emergencia a cosecha, presencia de la enfermedad, peso y número de tubérculos a cosecha. Los resultados obtenidos fueron sometidos a análisis de la varianza y prueba de diferencia mínima de Fisher. Los resultados indicaron que no hubo diferencias (P <= 0,05) entre tratamientos para la variable emergencia, con un promedio general para el ensayo de 12 días. El período de emergencia a cosecha presentó diferencias (P <= 0,05) entre los niveles de humedad, con un mayor período para el nivel más alto (50-55%). La enfermedad se presentó sólo en los tratamientos inoculados con el hongo A. solani, principalmente en la variedad Cardinal; sólo en una planta de Mirka se desarrollaron tumores de carbón. No se observó efecto de los niveles de humedad en el suelo sobre el desarrollo del hongo.

Ovos de Enterobius vermicularis foram encontrados em coprólitos humanos coletados no sítio arqueológico de Caserones, Vale da Tarapaca, no Chile, com datações de 400 BC a 800 AD. Este parasito humano já foi encontrado em outros sítios arqueológicios nas Américas e, a partir desses achados, discute-se a sua introdução neste continente.

Enterobius vermicularis eggs were found in human coprolites collected in the archaeological site of Caserones, Tarapaca Valley, Chile, dating from 400 BC to 800 AD. The human pinworm had already been found in other pre-historic archaeological sites in America, and its introduction in this continent is discussed.