Frequency of IFNγ-producing T cells correlates with seroreactivity and activated T cells during canine Trypanosoma cruzi infection.

Vaccines to prevent Trypanosoma cruzi infection in humans or animals are not available, and in many settings, dogs are an important source of domestic infection for the insect vector. Identification of infected canines is crucial for evaluating peridomestic transmission dynamics and parasite control strategies. As immune control of T. cruzi infection is dependent on humoral and cell-mediated immune responses, we aimed to define a serodiagnostic assay and T cell phenotypic markers for identifying infected dogs and studying the canine T. cruzi-specific immune response. Plasma samples and peripheral blood mononuclear cells (PBMCs) were obtained from forty-two dogs living in a T. cruzi-endemic region. Twenty dogs were known to be seropositive and nine seronegative by conventional serologic tests two years prior to our study. To determine canine seroreactivity, we tested sera or plasma samples in a multiplex bead array against eleven recombinant T. cruzi proteins. Ninety-four percent (17/18) of dogs positive by multiplex serology were initially positive by conventional serology. The frequency of IFNγ-producing cells in PBMCs responding to T. cruzi correlated to serological status, identifying 95% of multiplex seropositive dogs. Intracellular staining identified CD4+ and CD8+ T cell populations as the sources of T. cruzi lysate-induced IFNγ. Low expression of CCR7 and CD62L on CD4+ and CD8+ T cells suggested a predominance of effector/effector memory T cells in seropositive canines. These results are the first, to our knowledge, to correlate T. cruzi-specific antibody responses with T cell responses in naturally infected dogs and validate these methods for identifying dogs exposed to T. cruzi.

Pharmacokinetic and pharmacodynamic properties of enrofloxacin in southern crested caracaras (Caracara plancus).

To determine the dosage of enrofloxacin in southern crested caracaras (Caracara plancus), plasma concentrations of enrofloxacin were measured by high-performance liquid chromatography after intravenous (IV) (5 mg/kg) and intramuscular (IM) (10 mg/kg) administration. This compound presented a relatively high volume of distribution (2.09 L/kg), a total body clearance of 0.24 L/kg x h, and a long permanence as shown by an elimination half-life of 7.81 hours after IV administration and a terminal half-life of 6.58 hours after IM administration. The areas under the concentration-time curves (AUC) were 21.92 and 34.38 microg x h/mL for IM and IV administration, respectively. Enrofloxacin was rapidly absorbed after IM administration with a time to reach maximum concentration of 0.72 hours and bioavailability of 78.76%. After IM administration, the peak drug concentration (C(max)) was 3.92 microg/mL. Values of minimum inhibitory concentration (MIC), C(max), and AUC have been used to predict the clinical efficacy of a drug in treating bacterial infections, with a C(max)/MIC value of 10 and an AUC/MIC ratio of 125-250 associated with optimal bactericidal effects. By using the study data and a MIC breakpoint of 0.25 microg/mL, values of C(max)/MIC were 13.74 and 15.94 and for AUC/MIC were 90.73 and 139.63, for the IV and IM routes respectively. For the treatment of infectious diseases caused by microorganisms with MIC < or = 0.25 microg/mL, the calculated optimal dosages were 7.5 and 9.5 mg/kg q24h by the IV and IM routes, respectively. For less susceptible bacteria, a dose increase should be evaluated. To treat caracara by the IV route against microorganisms with MIC < or = 0.25 microg/mL, the dose should be higher than the 5 mg/kg used in our study, but possible side effects derived from an increase in the IV dose and efficacy in sick birds should be assessed.

Factores ecoambientales relacionados con potenciales reservorios de Leptospira spp. en la Reserva Ecológica Costanera Sur, Buenos Aires, Argentina / Eco-environmental Factors Related to Potential Reservoirs of Leptospira spp. in the Costanera Sur Ecological Reserve, Buenos Aires, Argentina

Resumen Las modificaciones ambientales generan entornos de interfaz en los que la transmisión de Leptospira spp. puede verse afectada. Con el objetivo de identificar y analizar variables ecoambientales asociadas a potenciales reservorios de Leptospira spp. en la Reserva Ecológica Costanera Sur (RECS) (Buenos Aires, Argentina) y áreas urbanizadas contiguas, se realizó un muestreo por conveniencia en líneas transectas, estratificado y proporcionado. Fueron capturados 170 mamíferos de 11 especies y se analizó la presencia de Leptospira spp. por serología, cultivo y PCR. En áreas conservadas, se registraron mayormente Didelphis albiventris y Deltamys kempi, mientras que Oligoryzomys flavescens también fue hallado en áreas degradadas, y Rattus norvegicus solo fue encontrada en áreas degradadas. No se detectó Leptospira spp. en los mamíferos silvestres. Un perro sin tenedor responsable resultó positivo por serología. Las condiciones ambientales de la RECS sugieren un ecosistema poco propicio para Rattus, evidenciando la importancia de la conservación de áreas naturales en entornos urbanos.

Abstract Environmental modifications generate interface environments in which Leptospira spp. transmission may be affected. In order to identify and analyze eco-environmental variables associated with potential reservoirs of Leptospira spp. in the Reserva Ecológica Costanera Sur (RECS) (Buenos Aires, Argentina) and adjacent urbanized areas, a stratified and proportionate transect line convenience sampling was carried out. A total of 170 mammals of 11 species were captured and analyzed for the presence of Leptospira spp. by serology, culture and PCR. In conserved areas, Didelphis albiventris and Deltamys kempi were mostly recorded, while Oligoryzomys flavescens was also found in degraded areas, and Rattus norvegicus was only found in degraded areas. Leptospira spp. were not detected in wild mammals. One dog without a responsible keeper tested positive by serology. The environmental conditions of the RECS suggest a poor ecosystem for Rattus, demonstrating the importance of the conservation of natural areas in urban environments.

Molecular identification of Anaplasma marginale in two autochthonous South American wild species revealed an identical new genotype and its phylogenetic relationship with those of bovines.

BACKGROUND: Anaplasma marginale is a well-known cattle pathogen of tropical and subtropical world regions. Even though, this obligate intracellular bacterium has been reported in other host species different than bovine, it has never been documented in Myrmecophaga tridactyla (giant anteater) or Hippocamelus antisense (taruca), which are two native endangered species. METHODS: Samples from two sick wild animals: a Myrmecophaga tridactyla (blood) and a Hippocamelus antisense (blood and serum) were studied for the presence of A. marginale DNA through msp5 gene fragment amplification. Further characterization was done through MSP1a tandem repeats analysis and MLST scheme and the genetic relationship among previously characterized A. marginale sequences were studied by applying, eBURST algorithm and AMOVA analysis. RESULTS: Anaplasma marginale DNA was identified in the Myrmecophaga tridactyla and Hippocamelus antisense samples. Through molecular markers, we identified an identical genotype in both animals that was not previously reported in bovine host. The analysis through eBURST and AMOVA revealed no differentiation between the taruca/anteater isolate and the bovine group. CONCLUSIONS: In the present publication we report the identification of A. marginale DNA in a novel ruminant (Hippocamelus antisense) and non-ruminant (Myrmecophaga tridactyla) host species. Genotyping analysis of isolates demonstrated the close relatedness of the new isolate with the circulation population of A. marginale in livestock. Further analysis is needed to understand whether these two hosts contribute to the anaplasmosis epidemiology.

Trans-sialidase inhibition assay detects Trypanosoma cruzi infection in different wild mammal species.

The detection of Trypanosoma cruzi infection in mammals is crucial for understanding the eco-epidemiological role of the different species involved in parasite transmission cycles. Xenodiagnosis (XD) and hemoculture (HC) are routinely used to detect T. cruzi in wild mammals. Serological methods are much more limited because they require the use of specific antibodies to immunoglobulins of each mammalian species susceptible to T. cruzi. In this study we detected T. cruzi infection by trans-sialidase (TS) inhibition assay (TIA). TIA is based on the antibody neutralization of a recombinant TS that avoids the use of anti-immunoglobulins. TS activity is not detected in the co-endemic protozoan parasites Leishmania spp and T. rangeli. In the current study, serum samples from 158 individuals of nine wild mammalian species, previously tested by XD, were evaluated by TIA. They were collected from two endemic areas in northern Argentina. The overall TIA versus XD co-reactivity was 98.7% (156/158). All 18 samples from XD-positive mammals were TIA-positive (co-positivity, 100%) and co-negativity was 98.5% (138/140). Two XD-negative samples from a marsupial (Didelphis albiventris) and an edentate (Dasypus novemcinctus) were detected by TIA. TIA could be used as a novel tool for serological detection of Trypanosoma cruzi in a wide variety of sylvatic reservoir hosts.

trans-Sialidase neutralizing antibody detection in Trypanosoma cruzi-infected domestic reservoirs.

The detection of Trypanosoma cruzi infection in domestic dogs and cats is relevant to evaluating human transmission risks and the effectiveness of insecticide spraying campaigns. However, the serological assays routinely used are associated with cross-reactivity in sera from mammals infected with Leishmania spp. We used a trans-sialidase inhibition assay (TIA) for T. cruzi diagnosis in serum samples from 199 dogs and 57 cats from areas where these types of infections are endemic. TIA is based on the antibody neutralization of recombinant trans-sialidase, an enzyme that is not detected in the coendemic Leishmania species or Trypanosoma rangeli parasites. T. cruzi infection was also evaluated by conventional serology (CS) (indirect immunofluorescence, indirect hemagglutination, enzyme-linked immunosorbent assay, and immunochromatographic dipstick test) and xenodiagnosis. Sera from 30 dogs and 15 cats from areas where these organisms are not endemic and 5 dogs with visceral leishmaniasis were found to be nonreactive by TIA and CS. Samples from dogs and cats demonstrated 91 and 95% copositivities between TIA and CS, whereas the conegativities were 98 and 97%, respectively. Sera from xenodiagnosis-positive dogs and cats also reacted by TIA (copositivities of 97 and 83%, respectively). TIA was reactive in three CS-negative samples and was able to resolve results in two cat serum samples that were CS inconclusive. Our study is the first to describe the development of trans-sialidase neutralizing antibodies in naturally infected dogs and cats. High CS conegativity and the absence of trans-sialidase neutralization in dog sera from areas where leishmaniasis is not endemic and from dogs with visceral leishmaniasis support TIA specificity. The TIA may be a useful tool for T. cruzi detection in the main domestic reservoirs.

Preeclampsia leve: cuidados en casa / Home care in mild pre - eclampsia

El presente estudio tiene como objetivo detectar las necesidades de cuidado percibidas por gestantes con diagnóstico de preeclampsia leve que manejan su patología en casa. Se realizó una investigación cualitativa descriptiva exploratoria entrevistando mujeres gestantes con este diagnóstico atendido en el Hospital de San José de Bogotá DC. Para determinar el número que se necesitaba se tuvo en cuenta el principio de saturación, el cual se cumplió con ocho pacientes. El análisis de los datos fue hecho por edición y fundamentado en la teoría de suplencia o ayuda a través del modelo de necesidades humanas para la vida y la salud, como núcleo en la acción de enfermería de Virginia Henderson, en el cual se encontró que estas enfermas requieren un estricto cuidado en el manejo de cuatro necesidades básicas que son fisiológicas, de seguridad, de amor y pertenencia, y de autorrealización. En cada una de ellas las más relevantes fueron: toma de tensión arterial, tranquilidad, afecto de su familia y más información acerca de la patología que padecen. La realidad vista en la presente investigación genera gran expectativa frente a la importancia de la participación del enfermero profesional en el cuidado de la gestante con la patología mencionada, tanto en el área de promoción y prevención como en el diagnóstico precoz, tratamiento oportuno y limitación del daño.

The purpose of this study is to detect the perceptions on required care of women with mild pre-eclampsia who handle their condition at home. A qualitative, descriptive, exploratory research was undertaken surveying women with this diagnosis seen at the San José Hospital in Bogotá D.C. The saturation principle was used to determine the required number, which was met by eight patients. Data analysis was performed by edition and was based on the substitution theory or help through human necessities for life and health, as the fundamentals of the Virginia Henderson theories, which found that this condition requires strict management of four essential necessities, that is, physiological needs, love assurance, emotional bonds (attachment) and self-realization. The most relevant in each of them were: taking of blood pressure, tranquility, receiving love and reassurance from their families and being more informed about their condition. The actual results of this research cause great expectations as to the importance of the nursing professional in the care of these patients, especially in the promotion of health and prevention of disease as well as on timely diagnosis and treatment and limitation of harm.