In utero betamethasone affects 3ß-hydroxysteroid dehydrogenase and inhibin-α immunoexpression during testis development.

Prenatal glucocorticoids, commonly used in women at risk of preterm delivery, can predispose the newborn to disease in later life. Since male reproductive function is likely to reflect testis development during fetal life, we studied the effects of prenatal glucocorticoids on two key intra-testicular factors that play roles in cellular proliferation and differentiation, 3ß-hydroxysteroid dehydrogenase (3ß-HSD) and inhibin-α. Pregnant sheep (n=42) were treated with betamethasone (0.5 mg/kg) or saline (control) at 104, 111 and 118 days of gestation (DG). Testicular tissue was sampled from fetuses at 121 and 132DG, and from lambs at 45 and 90 postnatal days (PD). Within the betamethasone treated group, 3ß-HSD immunostaining area was greater at 121DG than at 90PD (P=0.04), but the intensity of immunostaining was higher at 90PD than at 121DG (P=0.04), 132DG (P=0.04) and 45PD (P=0.03). Control animals showed no changes in 3ß-HSD area or intensity of immunostaining. No significant differences were observed between treated and control animals in immunostaining area, but immunostaining was more intense in the treated group than in the control group at 90PD (P=0.03). For inhibin-α, the proportion of immunostaining area declined in treated offspring from 121DG to 45PD, in contrast to control values, but recovered fully by 90PD, concomitantly with the onset of spermatogenesis. In conclusion, prenatal betamethasone increased the postnatal testicular expression of inhibin-α but reduced the expression of 3ß-HSD. These effects could compromise androgen-mediated testicular development and therefore adult capacity for spermatogenesis.

Viabilidad de huevos de helmintos en biosólidos

El trabajo consistió en determinar el tiempo de almacenamiento (deshidratación natural en zona de clima templado) necesario para que los lodos acumulados en las lagunas de sedimentación, pudiesen ser utilizados en la agricultura sin riesgo sanitario, para lo cual se estudio la viabilidad de los huevos de helmintos a través del tiempo. Dado que la concentración de huevos de helmintos parásitos en los lodos de la localidad de Alcorta, prov. de Santa Fe, fue baja (1-2 huevos/g MS) se decidio adicionar huevos de Ascaris artificialmente, para estudiar su viabilidad

Viabilidad de huevos de helmintos en biosólidos

El trabajo consistió en determinar el tiempo de almacenamiento (deshidratación natural en zona de clima templado) necesario para que los lodos acumulados en las lagunas de sedimentación, pudiesen ser utilizados en la agricultura sin riesgo sanitario, para lo cual se estudio la viabilidad de los huevos de helmintos a través del tiempo. Dado que la concentración de huevos de helmintos parásitos en los lodos de la localidad de Alcorta, prov. de Santa Fe, fue baja (1-2 huevos/g MS) se decidio adicionar huevos de Ascaris artificialmente, para estudiar su viabilidad

Investigating helminth eggs and Salmonella sp. in stabilization ponds treating septage.

Sludge management arises as a relevant problem after being accumulated in primary ponds of septage treatment plants. One of the most attractive options for sludge disposal is its use in agriculture and then specific guidelines regarding hygienic quality must be fulfilled. This study aimed at evaluating the storage time needed to inactivate Ascaris eggs and Salmonella in sludge accumulated in a primary pond treating septage. Raw septage exhibited very low concentrations of viable Ascaris eggs, thus experiments with Ascaris suum eggs spiking were conducted. The concentration of Ascaris eggs in the solids accumulated at the bottom of the pond was 20 eggs/g of total solids (g TS) at the time of pond closure. Although it decreased, some eggs remained viable (0.59 mean viable eggs/g TS) up to 20 months of in-pond storage of the biosolids. Salmonella survival was studied after developing an analytical method that inhibited the native flora. Sludge was seeded with Salmonella enteritidis. An equation adequately describing Salmonella die-off in biosolids subjected to 115 days of in-pond storage/dewatering, was found to be represented by the regression: y = log MPN Salmonella/g TS = 6.67 x t(-0.086), with t = storage time elapsed in days. The initial concentration was 7.0 x 10(6) MPN/g TS and the removal efficiency was 99%.

Isolation of Salmonella sp. in sludge from septage treatment plant.

Waste stabilization ponds (WSP) are an often-used option to treat faecal sludges collected from on-site sanitation systems. Since agricultural use is one of the most attractive options for sludge disposal, specific guidelines on the hygienic sludge quality must be fulfilled, such as for viable helminth eggs and Salmonella sp. Although Salmonella isolation methods are well known for other types of samples, they are not suitable for faecal sludge. The reason can be attributed to the co-existence of a native bacterial sludge flora masking Salmonella development, especially if this bacteria is present at low concentrations. In order to select the best methodology for Salmonella recovery from septage sludge, different culture media were assayed at different incubation periods and temperatures. The proposed methodology for Salmonella recovery from sludge can be summarised as follows: (1) enrichment in Rappaport-Vassiliadis broth at 43 degrees C, 48 hours, and (2) isolation in XLD agar at 40 degrees C, 24 hours. Identification of suspected colonies by biochemical tests: TSI, LIA, urease and serological confirmation with Group O Antigen.

Remoción biológica de hierro y manganeso, una tecnología apropiada

El estudio tuvo como objetivo el desarrollo de un proceso adecuado de remoción de hierro y manganeso en aguas subterráneas, para ser usado en el diseño de plantas para pequeñas y medianas poblaciones. El sistema estudiado comprende las siguientes etapas: aeración, prefiltración ascendente en mantos de grava, y filtración lenta en arena. Los ensayos en plantas piloto utilizaron dos calidades de aguas subterráneas, y en pruebas previas a los mismos se detectó la presencia de bacterias del hierro en agua cruda. Los ensayos demostraron que la prefiltración juega un rol preponderante en la línea de tratamiento

The challenge of faecal sludge management in urban areas--strategies, regulations and treatment options.

In urban centres of industrialising countries, the majority of houses are served by on-site sanitation systems such as septic tanks and unsewered toilets. The faecal sludges (FS) collected from these systems are usually discharged untreated into the urban and peri-urban environment, posing great risks to water resources and to public health. Contrary to wastewater management, the development of strategies to cope with faecal sludges, adapted to the conditions prevailing in developing countries, have long been neglected. The authors describe the current situation and discuss selected issues of FS management. A proposal is made for a rational setting of sludge quality or treatment standards in economically emerging countries. The authors stipulate that regulatory setting should take into account local economic, institutional and technical conditions. Defining suitable treatment options as critical control points in securing adequate sludge quality is better than setting and relying on numerical sludge quality standards. A separate section is devoted to the practice and to regulatory aspects of (faecal) sludge use in Argentina. An overview of treatment options, which may prove sustainable in less industrialized countries is provided. Planted sludge drying beds are one of these options. It has been piloted in Thailand for four years and details on its performance and operation are presented along with data on the hygienic quality of treated biosolids.

Cotreatment of sewage and septage in waste stabilization ponds.

A one year study was carried out in a waste stabilization ponds system where septage and sewage are cotreated. The system consists of two septage ponds which operate alternately followed by two ponds in series which receive the combined effluent. The septage ponds also act as evaporation ponds for the accumulated sludge. The monitoring program was divided in two phases. The results of the first phase indicate that the effluent of septage ponds has an adequate quality to be discharged into the waste stabilization ponds designed to treat sewage and that is possible to use the septage ponds to dry the accumulated sludge. Further investigation is needed to find suitable post-treatment of the sludge in order to use it in agriculture.

Remoción de plancton en el proceso filtración rápida

Se presentan los primeros resultados de un proyecto de investigación iniciado en el Centro de Ingeniería Sanitaria conjuntamente con el Ente Regulador de Servicios Sanitarios, relacionado con la exigencia de ausencia de zoo y fitoplancton establecidas en las Normas de calidad de agua potable vigentes en la Pcia. de Santa Fe. Se realizaron ensayos de filtración en un filtro piloto, divididos en dos etapas, laboratorio y campo. Los objetivos fueron determinar la influencia de la velocidad de filtración en la remoción de organismos planctónicos y la evaluación del contaje de microorganismos como herramienta de control del proceso de filtración. No es conveniente utilizar velocidades de filtración mayores a 10 m/h. El trabajo tambien se encuentra en la revista ISA 38

Experiencias de eliminación de hierro y manganeso desarrolladas en la provincia de Santa Fe

En el presente trabajo se intenta dar una visión de la situación en la que se encuentra la pcia. de Santa Fe en cuanto al problema del hierro y manganeso en las fuentes subterráneas por una parte y además experiencias sobre tratamiento para su eliminación en agua potable y en efluentes industriales. Los tratamientos utilizados fundamentalmente consisten en procesos de aeración natural seguida de agregado de oxidantes químicos. Por otra parte se presenta un anteproyecto de planta de eliminación de hierro realizado en Las Toscas donde se utiliza filtración directa