Abstract Leptospirosis remains as a major public health problem nowadays, mainly affecting vulnerable communities with low socioeconomic resources. In this study, the molecular detection of pathogenic leptospires from environmental samples (water and mud) from northern Argentina (Formosa, Salta, Santiago del Estero, Misiones and Chaco provinces) is described. Samples were obtained from regions with varied climatological features, all inhabited by vulnerable communities. From the 89 samples that were analyzed, 24.7% showed molecular evidence of the presence of pathogenic leptospires. Prevalence by sample type was: 27.8% in water samples and 11.8% in mud samples. All the sampled regions showed at least one positive sample. This result highlights the need of further research regarding leptospirosis in different regions of Argentina.

Resumen La leptospirosis continúa siendo hoy en día un problema para la salud pública, principalmente en poblaciones de bajos recursos socioeconómicos. En este trabajo se presenta la detección de leptospiras patógenas en muestras ambientales (aguas y barros) provenientes de regiones del norte argentino (provincias de Formosa, Salta, Santiago del Estero, Misiones y Chaco) con variadas características climatológicas habitadas por poblaciones vulnerables. De las 89 muestras analizadas, en el 24,7% fue posible detectar molecularmente la presencia de leptospiras patógenas. La prevalencia por tipo de muestra fue de 27,8% para las aguas y 11,8% para los barros. Todas las localidades muestreadas presentaron al menos una muestra positiva a alguna de las pruebas realizadas, por lo que el presente trabajo refleja la necesidad de profundizar los estudios de la leptospirosis en distintas regiones de la Argentina.

Abstract Molecular tools have improved conventional veterinary diagnosis. Acid nucleic extraction is a key step for downstream applications. This work aimed to compare the DNA extraction method Chelex-100 resin (M1) with Whatman® cards (M2), phenol-chloroform (M3), or commercial kits (M4), and to determine the most sensitive and inexpensive one for its diagnosis of animal pathogens that, despite their economic or zoonotic relevance, receive little attention. DNA was isolated from urine, organs, semen, blood and intestinal mucous, from the bacteria Leptospira interrogans serovar Pomona Pomona (by M1 and M2), Brucella melitensis (by M1, M3 and M4), and Salmonella ser. Abortusequi (by M1 and M4), and the parasites Leishmania spp. (by M1, M3 and M4), and Eimeria spp. (by M1 and M3), respectively. The sensitivity of each method was assayed by Polymerase Chain Reaction (PCR). The M1 showed similar sensitivity for Salmonella ser. Abortusequi, Leishmania spp., and Eimeria spp., being better for L. interrogans serovar Pomona Pomona and slightly lower for B. melitensis. For the first time, a simple and economic method was successfully employed for extracting DNA from these animal pathogens, especially important in low-resource settings, contributing to the diagnosis of leptospirosis, brucellosis, leishmaniasis, and coccidiosis; as well as to the molecular epidemiology of salmonellosis in stallion from semen samples.

Bovine leptospirosis is an important zoonotic disease whose molecular diagnosis is widely reported. However, there is not a unique method of extraction of DNA for pathogenic leptospires using clinical samples. In this study, bovine urine was contaminated with pure culture of L. interrogans serovar Pomona Pomona in order to compare three of them: M1.) Chelex-100 resin, M2.) FTA Whatman paper and M3.) boiling of the sample (in-house protocol), being the first one the most sensitive when used in diagnostic PCR, detecting up to 2x102 leptospiras/mL. The methodology proposed in this study turned out to have good performance for the detection of leptospires in animal clinical samples, although it should be applied to a greater number of samples and in different stages of the pathology.

La leptospirosis bovina es una importante enfermedad zoonótica cuyo diagnóstico molecular está ampliamente divulgado. Sin embargo, no existe un método único de extracción de ADN para leptospiras patógenas a partir de muestras clínicas. En este trabajo se utilizó orina bovina contaminada con cultivo de L. interrogans serovar Pomona Pomona para analizar el mejor método comparando: M1.) resina Chelex-100, M2.) papel FTA Whatman y M3.) hervido de la muestra (protocolo casero). De estas tres técnicas, la primera (M1) presentó la mayor sensibilidad al realizar la PCR de diagnóstico, detectándose hasta 2x102 leptospiras/mL. La metodología aquí planteada resultó tener buen rendimiento para la detección de leptospiras en muestras clínicas animales, aunque es necesario su validación con mayor número y diversidad de muestras.

Este trabalho reporta o estudo de compostos binários do dicarboxilato 1,4-bis(3-carbóxi-3-oxo-prop-1-enil)benzeno, C6H4(-CH=CH-CO-COO-)2 , com os cátions metálicos Ag+ e Pb2+, obtidos a partir de soluções aquosas do ligante e dos nitratos dos cátions metálicos, em proporções estequiométricas. Para a caracterização e o estudo do processo de decomposição térmica desses compostos foram empregadas Espectrofotometria de Absorção na Região do Infravermelho com Transformada de Fourier (FT-IR), Análise Elementar (C, H), Complexometria com EDTA, Termogravimetria (TG) e Calorimetria Exploratória Diferencial (DSC).

This work reports the study of solid binary compounds of the 1,4-bis(3-carboxy-3-oxo-prop-1-en-1-yl)benzene dicarboxilate [Bis-BP], C6H4(-CH=CH-CO-COO-)2 , with the metal ions Ag+ and Pb2+. The compounds were obtained from adition of aqueous solutions of the metal ions to the aqueous solution of the ligand, in stoichometric ratio. Characterization and study of the process of thermal decomposition of these compounds were performed by Fourier Transform Infrared Spectroscopy (FT-IR), Elemental Analysis (C, H), EDTA Tritation, Thermogravimetry (TG) and Differencial Scanning Calorimetry(DSC).