RESUMEN Objetivo. Estimar la prevalencia del tracoma en poblaciones indígenas y no indígenas en determinadas zonas del estado de Maranhão, en el nordeste de Brasil. Métodos. Se trató de una encuesta de ámbito poblacional con muestreo probabilístico. Para el diagnóstico del tracoma, se realizó un examen ocular externo con una lupa frontal de 2,5X aumentos. Se estimó la prevalencia de la inflamación tracomatosa folicular (TF) en la población infantil de 1 a 9 años y la prevalencia de la triquiasis tracomatosa (TT) en la población de 15 años o más. Se obtuvieron las frecuencias relativas de las características sociodemográficas y ambientales. Resultados. En el estudio participaron 7 971 personas, 3 429 de poblaciones no indígenas y 4 542 de poblaciones indígenas. La prevalencia de la TF en las poblaciones no indígenas e indígenas fue de 0,1% y 2,9%, respectivamente, en tanto que la de la TT en las poblaciones indígenas fue de 0,1%. Conclusiones. La prevalencia de la TF y la TT en las dos unidades de evaluación del estado de Maranhão estuvo dentro de los límites recomendados para la eliminación del tracoma como problema de salud pública. Sin embargo, la prevalencia de la TF fue mayor en la unidad de evaluación indígena, lo que indica una mayor vulnerabilidad de esta población a la enfermedad. La prevalencia de la TF inferior al 5,0% implica una reducción de la transmisión, que puede haber sido consecuencia tanto de la mejora de las condiciones socioeconómicas como de la aplicación de la estrategia SAFE de la Organización Mundial de la Salud.

ABSTRACT Objective. To estimate the prevalence of trachoma in indigenous and non-indigenous populations in selected areas of the state of Maranhão, in northeastern Brazil. Methods. This was a population-based survey with probabilistic sampling. For the diagnosis of trachoma, external ocular examination was performed using head magnifying loupes, at 2.5X magnification. The prevalence of trachomatous inflammation – follicular (TF) in children aged 1–9 years and the prevalence of trachomatous trichiasis (TT) in the population aged ≥15 years were estimated. Relative frequencies of sociodemographic and environmental characteristics were obtained. Results. The study included 7 971 individuals, 3 429 from non-indigenous populations and 4 542 from indigenous populations. The prevalence of TF in non-indigenous and indigenous populations was 0.1% and 2.9%, respectively, and the prevalence of TT among indigenous populations was 0.1%. Conclusions. The prevalence of TF and TT in the two evaluation units in the state of Maranhão were within the limits recommended for the elimination of trachoma as a public health problem. However, the prevalence of TF was higher in the indigenous evaluation unit, indicating a greater vulnerability of this population to the disease. The prevalence of TF of below 5.0% implies a reduction in transmission, which may have resulted from improved socioeconomic conditions and/or the implementation of the World Health Organization SAFE strategy.

RESUMO Objetivo. Estimar a prevalência do tracoma em populações indígenas e não indígenas em áreas selecionadas do estado do Maranhão, na região Nordeste do Brasil. Métodos. Inquérito de base populacional com amostragem probabilística. Para o diagnóstico de tracoma, foi realizado exame ocular externo com o auxílio de lupas binoculares com ampliação de 2,5×. Foram estimadas a prevalência de inflamação tracomatosa folicular (TF) em crianças de 1 a 9 anos de idade e a prevalência de triquíase tracomatosa (TT) na população com idade ≥15 anos. Foram obtidas as frequências relativas das características sociodemográficas e ambientais. Resultados. O estudo incluiu 7 971 indivíduos (3 429 de populações não indígenas e 4 542 de populações indígenas). A prevalência de TF nas populações não indígenas e indígenas foi de 0,1% e 2,9%, respectivamente, e a prevalência de TT entre as populações indígenas foi de 0,1%. Conclusões. A prevalência de TF e TT nas duas unidades de avaliação no estado do Maranhão ficou dentro dos limites recomendados para a eliminação do tracoma como problema de saúde pública. No entanto, a prevalência de TF foi maior na unidade de avaliação indígena, indicando uma maior vulnerabilidade dessa população à doença. A prevalência de TF abaixo de 5,0% implica uma redução na transmissão, que pode ter sido resultado de melhores condições socioeconômicas e da implementação da estratégia SAFE da Organização Mundial da Saúde.

ABSTRACT Vitellogenins (Vtg) are glycolipophosphoproteins synthesized by oviparous vertebrates as yolk proteins precursors. These proteins have been studied for their role in reproduction and in endocrine disruption. In this work, we report the first proteomic study towards the characterization of Vtg from Pseudoplatystoma fasciatum, Piaractus brachypomus and Colossoma macropomum. Male specimens of each of the three fish species were estradiol-induced (experimental) and non-induced (control). The initial Vtg characterization was made by 2D protein gel electrophoresis of both groups The identification of the high molecular weight spots, presumed to be Vtgs, was assessed by MALDI-TOF mass spectrometry analysis. A post-translational modification study was performed by differential staining of 2D gels in order to visualize phosphoproteins and glycoproteins. Plasma samples from the three species, induced with estrogen, showed three high molecular weight spots with variable isoelectric points. Post-translational modifications showed that Vtgs from P. brachypomus and C. macropomum presented a phosphorylated and glycosylated subunit, while the same subunit in P. fasciatum was only glycosylated. This characterization will help in the development of reliable immunoassays, which could be used for studies of endocrine disruption or for the improvement of artificial spawning, by uncovering the time of fish maturation or sex determination.

La coagulación causa la coalescencia de material suspendido, lo cual generalmente se logra adicionando sustancias químicas al agua. Sin embargo, dado que algunas de estas sustancias se han asociado a problemas de salud, diversos investigadores estudian como alternativa coagulantes naturales obtenidos de especies vegetales. Por esta razón, se evaluó la efectividad de un coagulante extraído del cardón Stenocereus griseus en la potabilización del agua. Para ello, se recolectaron muestras de agua cruda natural en la planta de tratamiento Pueblo Viejo (estado Zulia, Venezuela) y a partir de éstas se prepararon aguas diluidas con turbiedades iniciales de 20, 30, 40, 50, 60, 70, 80, 90 y 100 NTU. Estas aguas fueron tratadas con diferentes dosis (300, 400, 500 y 600 ppm) del coagulante natural. Se evaluaron los parámetros pH, turbidez, color y alcalinidad en las aguas crudas y en las tratadas. Después de aplicar las dosis óptimas del coagulante (300, 400, 500 y 600 ppm), los porcentajes de remoción de turbidez oscilaron entre 14,50 y 80,42% antes de la simulación de la filtración y entre 69,27 y 96,46% luego de ello. Esto demostró la efectividad del coagulante extraído de Stenocereus griseus (Haw.) Buxb. en la potabilización de agua.

The coagulation causes suspended material coalescence, which generally is done by adding chemical substances to the water. Nevertheless, since some of these substances have been associated to health problems, several researchers study as an alternative natural coagulants obtained from vegetables species. For this reason, it was evaluated the effectiveness of a coagulant extracted from the cactus Stenocereus griseus in water purification. For this, there were collected samples of natural crude water at the treatment plant of Pueblo Viejo (Zulia state, Venezuela) and from them they were prepared diluted waters with initial turbidity of 20, 30, 40, 50, 60, 70, 80, 90, and 100 NTU. These waters were treated with different doses (300, 400, 500, and 600 ppm) of natural coagulant. pH, turbid, color, and alkalinity parameters were evaluated in the crude and treated waters. After the coagulant optimum dose was applied (300, 400, 500, and 600 ppm), turbidity removal percentages oscillated between 14.50 and 80.42% before purification simulation and between 69.27 and 96.46% after it. This demonstrated the effectiveness of the coagulant extracted from Stenocereus griseus (Haw.) Buxb. in water purification.

Se realizó un estudio entomológico con el fin de conocer las especies flebotominas presentes en dos focos endémicos de leishmaniasis visceral americana (LVA) del estado Lara, Venezuela. Las capturas de flebotominos se realizaron, de enero 1998 a marzo 2000, en dos áreas endémicas localizadas en el municipio Torres: La Rinconada (10° 15’ N-69° 57’ W) y San Esteban (10° 54’ N-69° 55’ W). Para ello se colocó la trampa de luz Shannon, entre las 19: 00 y 22: 00 h, y 4 trampas de luz CDC durante toda la noche en el peridomicilio y, además, se realizó la búsqueda activa manual en sus refugios naturales. En La Rinconada se capturaron 7.488 ejemplares, pertenecientes a ocho especies flebotominas, de los cuales 6.782 fueron hembras y 706, machos. Lutzomyia pseudolongipalpis fue la especie predominante (94,59%). En San Esteban fueron capturados 1.032 ejemplares, de los cuales 842 fueron hembras y 190 machos. El 97,96% de los ejemplares fueron identificados como L. pseudolongipalpis. Ninguna de las hembras capturadas en las localidades endémicas estudiadas mostró la presencia de promastigotes de Leishmania spp. en su tracto digestivo. Debido al marcado predominio de L. pseudolongipalpis y la escasa presencia de L. evansi en estas áreas endémicas, L. pseudolongipalpis pudiera tener un rol importante en la transmisión de la leishmaniasis visceral en las localidades estudiadas.

An entomological study was undertaken to know the presence of phlebotomine species in two endemic foci of American Visceral Leishmaniasis (AVL) at Lara State, Venezuela. The captures of phlebotomine sand flies were carried out, from January 1998 to March 2000, in two endemic areas localized at the Torres municipality: La Rinconada (10° 15’ N-69° 57’ W) and San Esteban (10° 54’ N-69° 55’ W). For this purpose the Shannon light trap was used, between 19: 00 and 22: 00 h, and 4 CDC light traps left overnight at the peridomicily and, besides, active manual searches in its natural refuges was carried out. At La Rinconada, 7,488 specimens of eight phlebotomine species were caught out of which 6,782 were females and 706, males. Lutzomyia pseudolongipalpis was the predominant species (94.59%). At San Esteban 1,032 specimens were captured of which 842 were females and 190 males. The 97.96% of the specimens were identified as L. pseudolongipalpis. None of the females captured at the endemic localities that were studied showed the presence of Leishmania spp. promastigotes in their digestive tract. Due to the predominance of L. pseudolongipalpis and the low presence of L. evansi at these endemic areas, L. pseudolongipalpis should be regarded as having an important role in the transmission of American visceral leishmaniasis in the localities that were studied.

Different antigenic extracts of Taenia solium and Taenia crassiceps were evaluated in connection with the detection of antibodies in patients with neurocysticercosis aimed at selecting immunorelevant antigens for the diagnosis of neurocysticercosis by means of the immunoenzimatic assay and immunoblotting. The vesicular fluid of T. crassiceps proved to be more sensitive (100%) and specific (86%). On using the immunoblotting technique it was also observed that this extract was the most sensitive and specific. Within the protein profile of the antigen the band of 18 kDa was mostly recognized by the serum and cerebrospinal fluid of patients with neurocysticercosis. The vesicular fluid of T. crassiceps represents an alternative in the optimization of the diagnosis of neurocysticercosis in the serum and cerebrospinal fluid and in the substitution of T. solium antigens due to its high sensitivity and specificity and to its easy obtention under controlled laboratory conditions.

Se evaluaron diferentes extractos antigénicos de Taenia solium y de Taenia crassiceps en la detección de anticuerpos en pacientes con neurocisticercosis, con el objetivo de seleccionar antígenos inmunorrelevantes para el diagnóstico de la neurocisticercosis por medio del ensayo inmunoenzimático e immunoblotting. El fluido vesicular de T. crassiceps mostró ser más sensible (100 %) y específico (86 %). Por medio del immunoblotting se observó también, que este extracto fue el más sensible y específico. Dentro del perfil proteico del antígeno, la banda mayormente reconocida por el suero y líquido cefalorraquídeo de pacientes con neurocisticercosis fue la de 18 kDa. El fluido vesicular de la T. crassiceps por su alta sensibilidad y especificidad y por su facilidad de obtención en condiciones controladas de laboratorio, representa una alternativa en la optimización del diagnóstico de la neurocisticercosis en el suero y líquido cefalorraquídeo y en la sustitución de los antígenos de T. solium.