Lichens as bio-monitors of polycyclic aromatic hydrocarbons: Measuring the impact of features and traffic patterns.

The role of road characteristics, including gradient and speed control devices, in influencing emission dynamics remains to be fully elucidated. Most studies have focused on fuel consumption as an indirect indicator of sector emissions instead of directly quantifying specific pollutants, like polycyclic aromatic hydrocarbons (PAHs). This research approach is often due to the complexities involved in capturing these pollutants and their subsequent analysis. Bio-monitors, such as lichens, offer an economically viable method. Their wide distribution across various habitats enables the comparison of PAH levels in diverse environments. Against this background, The present work analyses the ability of tropical lichens to indicate the effect that traffic patterns and geometric design features of roads (traffic activity, road gradient, traffic control devices, and vehicular speed) have on the emission of PAH concentration. Results showed that PAHs in lichens strongly correlated with the road gradient (Spearman correlation, p<0.005 with R=0.98). Each 1% increase in road gradient implies a rise of 24 ngPAH/gLichen in National Road. Additionally, a trend coherent of PAH concentration with the vehicle speed profile was observed on Panamericana Road. Speed control devices were associated with higher concentrations of PAHs due to acceleration and braking actions that increment fuel consumption. Finally, the results evidenced that lichens helped determine the source of aromatics and their carcinogenic potential using the diagnostic ratio of PAHs and the carcinogenic equivalence sum, respectively.

[Production and evaluation of an antiserum for immunohistochemical detection of rabies virus in aldehyde fixed brain tissues]. / Elaboración y evaluación de un antisuero para la detección inmunohistoquímica del virus de la rabia en tejido cerebral fijado en aldehídos.

INTRODUCTION: The standard procedure for rabies diagnosis requires fresh samples of infected brain to be analyzed by two techniques, direct immunofluorescence and inoculation in mice. Rabies-infected, aldehyde-fixed brain tissues can be examined by immunohistochemistry, but the required commercial antibodies are scarce and expensive. OBJECTIVES: An anti-rabies antiserum was produced and tested to evaluate the effectiveness of rabies antigen detection in aldehyde preserved brain tissue. MATERIALS AND METHODS: Rabbits were inoculated with a rabies vaccine produced in Vero cells (origin-African green monkey kidney). Anti-rabies antiserum was obtained and tested by immunohistochemistry in aldehyde-fixed brain sections of rabies-infected mice. Several experimental conditions were assayed. The usefulness of the antiserum in human pathology samples was also tested. RESULTS: The specificity of the antiserum was demonstrated for immunohistochemical detection of rabies antigen in fixed aldehydes nervous tissue both from experimental material and pathology archival collection. In addition, the antiserum was successful in detecting rabies virus under conditions that have been considered unfavorable for the preservation of antigens. CONCLUSIONS: The inoculation of rabies vaccine in rabbits is an easy and safe procedure for obtaining antiserum useful for the detection of rabies antigen in samples of nervous tissue. Sections obtained on vibratome better preserve the viral antigenicity in comparison with paraffin-embedded tissues. This methods permit less expensive and more rapid immunohistochemical diagnosis of rabies.

Elaboración y evaluación de un antisuero para la detección inmunohistoquímica del virus de la rabia en tejido cerebral fijado en aldehídos / Production and evaluation of an antiserum for immunohistochemical detection of rabies virus in aldehyde fixed brain tissues

Introducción. El procedimiento estándar para el diagnóstico de la rabia requiere de muestras frescas del cerebro infectado, que se estudian mediante las técnicas de inmunofluorescencia directa y la inoculación en ratones. No obstante, a veces se necesita estudiar cerebros infectados con rabia mediante inmunohistoquímica de material fijado en aldehídos, pero los anticuerpos comerciales que se requieren son escasos y costosos. Objetivos. Elaborar un antisuero antirrábico y probar su efectividad para reconocer antígenos de rabia en tejido cerebral preservado en aldehídos. Materiales y métodos. Se inocularon conejos con una vacuna antirrábica producida en células Vero. Se obtuvo un antisuero que fue probado mediante inmunohistoquímica en cortes de cerebro de ratones infectados con rabia, obtenidos en diferentes condiciones experimentales y fijados en aldehídos. Además, se ensayó su utilidad en material de colección histopatológica de casos de rabia humana. Resultados. Se demostró la especificidad del antisuero obtenido para la detección inmunohistoquímica de antígenos de la rabia en tejido nervioso fijado con aldehídos y procedente de material experimental y del archivo histopatológico. Además, el antisuero resultó ser útil para la detección del virus rábico en condiciones que se consideran desfavorables para la preservación de antígenos. Conclusiones. La inoculación de vacuna antirrábica en conejos es un procedimiento fácil y seguro para la obtención de antisuero útil para la detección de antígenos de la rabia en muestras de tejido nervioso. Los cortes obtenidos con vibrátomo preservan mejor la antigenicidad en comparación con los tejidos incluidos en parafina, y permiten acortar el tiempo para hacer el diagnóstico inmunohistoquímico de la rabia.

Introduction. The standard procedure for rabies diagnosis requires fresh samples of infected brain to be analyzed by two techniques, direct immunofluorescence and inoculation in mice. Rabies-infected, aldehyde-fixed brain tissues can be examined by immunohistochemistry, but the required commercial antibodies are scarce and expensive. Objectives. An anti-rabies antiserum was produced and tested to evaluate the effectiveness of rabies antigen detection in aldehyde preserved brain tissue. Materials and methods. Rabbits were inoculated with a rabies vaccine produced in Vero cells (origin-African green monkey kidney). Anti-rabies antiserum was obtained and tested by immunohistochemistry in aldehyde-fixed brain sections of rabies-infected mice. Several experimental conditions were assayed. The usefulness of the antiserum in human pathology samples was also tested. Results. The specificity of the antiserum was demonstrated for immunohistochemical detection of rabies antigen in fixed aldehydes nervous tissue both from experimental material and pathology archival collection. In addition, the antiserum was successful in detecting rabies virus under conditions that have been considered unfavorable for the preservation of antigens. Conclusions. The inoculation of rabies vaccine in rabbits is an easy and safe procedure for obtaining antiserum useful for the detection of rabies antigen in samples of nervous tissue. Sections obtained on vibratome better preserve the viral antigenicity in comparison with paraffin-embedded tissues. This methods permit less expensive and more rapid immunohistochemical diagnosis of rabies.

Análisis de la oontaminación microbiológica (coiformes totales y fecales) en lla bahía de santa marta, caribe Colombiano / Analysis Of The Microbiological Contamination (Total And Fecales Coliforms) In The Bay Of Santa Marta, Colombian Caribbean

Con el fin de realizar un análisis del nivel de contaminación microbiológica y de las principales fuentes de contaminación en la Bahía de Santa Marta (BSM), se colectaron muestras de agua para medir las concentraciones de coliformes totales y fecales en 11 estaciones y dos niveles de profundidad (1 y 20 m). Para la época de mayores precipitaciones se encontraron altos valores de coliformes totales y fecales, en los dos niveles de profundidad; presentándose una condición similar para la época seca. Con base a una escala conceptual se obtuvo que la BSM presenta un grado de contaminación medio para actividades de contacto primario (natación y buceo), sin embargo, existen varias fuentes de contaminación (emisario submarino, río, puerto marítimo, entre otras) que están generando un alto impacto sobre este ecosistema. Los altos valores de contaminación que se registran en la BSM se encuentran asociados a la proximidad que tiene esta a las zonas urbanas.

With the purpose of making an analysis of the microbiological level of contamination and the main sources of contamination in the Bay of Santa Marta (BSM), water samples were collected to measure the concentrations of total and fecals coliforms in 11 stations and two levels of depth (1 and 20 m). For the time of greater precipitations were stops values of total and fecals coliforms, in both depth levels; appearing a similar condition for the dry time. Based on a conceptual scale it was obtained that the BSM presents an average degree of contamination for activities of primary contact (swimming and diving), nevertheless, exist several sources of contamination (submarine emissary, river, seaport, among others) that are generating a high impact on this ecosystem. The high values of contamination that are registered in the BSM find associate to the proximity that has this to the urban zones.