Detección de Salmonella enterica, desde aves silvestres acuáticas en Chile

Se considera a Salmonella enterica, como el principal agente causal de enfermedades transmitidas por losalimentos (ETA), siendo los productos avícolas, la fuente de infección más frecuente tanto a nivel mundial,como nacional. Sin embargo, se han descrito diversos reservorios silvestres para este patógeno, siendo el rolde las aves silvestres acuáticas (particularmente las que presentan patrones migratorios), un área deinvestigación incipiente en Chile, ya que se desconoce el rol de estas especies en la mantención ydiseminación de Salmonella spp.El objetivo principal de este trabajo, es la detección de Salmonella enterica desde heces frescas de avessilvestres acuáticas, en 5 regiones de Chile.De un total de 918 muestras, recolectadas entre Octubre de 2011 a Septiembre de 2012, se han aislado 28cepas de Samonella enterica, siendo S. Enteritidis (13/28, 46%) y S. Heildeberg (4/28, 14%) los serovaresmás frecuentes. Además se identificó a Salmonella Anatum, Havana, Agona, Infantis, Dublin, Seftenberg yuna cepa Grupo B (I 4, 5, 12:b:).Cabe destacar, que la Gaviota Dominicana (Larus dominicanus), ha sido la especie desde la cual se hanobtenido la mayoría de los aislados positivos. Además, se describen algunas características que explicaríanestos resultados: distribución geográfica amplia, adaptación a diversos ambientes, hábitos alimenticiosoportunistas, entre otras. En consecuencia, se debería considerar como un riesgo real para la Salud Pública,la presencia de Salmonella enterica en esta especie.  

Detection of antimicrobial resistant Salmonella enterica strains in samples of ground hedgehogs (Atelerix albiventris) reared as pets in the urban area of Santiago, Chile

The breeding of exotic pets has become a popular practice in Chile and, within this group of animals, small mammals such as guinea pigs and hedgehogs have gained importance due to their docile behaviour. The most common exotic hedgehog species in Chile is the African pygmy hedgehog (Atelerix albiventris). It has been reported that these pets are reservoirs of some zoonotic pathogens, among which Salmonella enterica constitutes an important threat for the owners. This study aimed to detect the presence of Salmonella strains in faeces from hedgehogs (Atelerix albiventris) admitted to a veterinary clinic in Santiago, Chile, and to characterise the antimicrobial susceptibility of the isolated strains. From 200 animals sampled, S. enterica was detected in 5 hedgehogs, corresponding to serotypes Muenchen (2), Infantis (2) and IV43:z4,z23:- (1). Furthermore, phenotypic antimicrobial resistance was determined in all subsp. enterica isolates. These results suggest that in Chile these exotic pets constitute a potential hazard for public health, therefore, supporting educational campaigns about basic biosecurity measures is necessary, mostly aimed at pet owners and risk groups

Desarrollo de una prueba de ELISA para el diagnóstico de infección por Brucella canis en perros

El diagnóstico definitivo y específico de la brucelosis en caninos causada por Brucella canis (B. canis) serealiza mediante el aislamiento de la bacteria desde muestras patológicas o sangre. Sin embargo, como laenfermedad se caracteriza por presentar periodos abacterémicos, un cultivo negativo no excluye laposibilidad de infección. La alternativa más ampliamente utilizada es la detección de anticuerpos frente a lainfección y debido a que tanto B. ovis y B. canis comparten componentes antigénicos con la cepa vacunaBrucella abortus RB51 (B. abortus CRB51), ésta podría ser usada como antígeno en el diagnósticoserológico de la enfermedad. En el presente estudio, se describe un enzimoinmunoensayo indirecto (ELISAI)para el serodiagnóstico de brucelosis canina utilizando un extracto altamente purificado delipopolisacárido rugoso (LPS-R) de Brucella abortus CRB51, cuyos resultados son comparados con latécnica contra inmunoelectroforesis (CIEF), que utiliza un antígeno extraído de una cepa de B. ovis, quecontiene tanto proteínas como al LPS rugoso. El análisis de los resultados indicó asociación estadística entreambas pruebas (p>0,05) para el diagnóstico de brucelosis canina. Además, ambas pruebas obtuvieron un altoíndice de concordancia (K= 0.961). Estos resultados hacen del ELISA-I propuesto una prueba promisoria alutilizar un antígeno más purificado y entregar resultados cuantitativos.  

Evolution of IFN-gamma response against mycobacterial antigens used for the diagnosis of bovine tuberculosis in BCG vaccinated cattle under a natural transmission setting in central Chile

Bovine tuberculosis (bTB) is a chronic disease of animals mainly caused by Mycobacterium bovis, a zoonotic pathogen that generates economic losses in the milk and meat industry. In central Chile, the Metropolitan Region concentrates dairy herds with the highest bTB prevalence of the country and the official veterinary service has supported the evaluation of the M. bovis Bacillus Calmette-Guerin (BCG) vaccine in this area with the replacement of tuberculin purified protein derivative (PPDs) by the DIVA (Differentiating Infected from Vaccinated Animals) peptides for the bTB diagnosis in the herds. This study aimed to describe the IFN-gamma response against PPDs (bovine and avian PPD) and DIVA antigenic cocktails (ESAT-6/CFP-10 and Rv3615c) in BCG vaccinated 11-month-old heifers under a natural transmission scenario. Sixty-two animals were vaccinated via subcutaneous route with a 2-8 x 105 colony forming units of BCG Russia strain and 60 control animals received sterile saline. Blood sampling was performed at time 0, previous to vaccination, and then at 3, 6, 9, 12, 15 and 18 months post-inoculation. The follow up of the IFN-gamma response in animals determined that the BCG vaccination interferes with the diagnosis of bTB using the traditional bovine PPD between 9 and 12 months post-inoculation. Furthermore, the sensitization with non-tuberculous mycobacteria (NTM) was also interfering the diagnosis relying in PPDs, suggesting the need of using DIVA antigens under this epidemiological condition, whether or not the BCG vaccine is administered in cattle, in order to improve the accuracy of bTB diagnosis in central Chile

Modified Intracellular-Associated Phenotypes in a Recombinant Salmonella Typhi Expressing S. Typhimurium SPI-3 Sequences

A bioinformatics comparison of Salmonella Pathogenicity Island 3 sequences from S. Typhi and S. Typhimurium serovars showed that ten genes are highly conserved. However three of them are pseudogenes in S. Typhi. Our aim was to understand what functions are lost in S. Typhi due to pseudogenes by constructing a S. Typhi genetic hybrid carrying the SPI-3 region of S. Typhimurium instead of its own SPI-3. We observed that under stressful conditions the hybrid strain showed a clear impairment in resistance to hydrogen peroxide and decreased survival within U937 culture monocytes. We hypothesized that the marT-fidL operon, encoded in SPI-3, was responsible for the new phenotypes because marT is a pseudogen in S. Typhi and has a demonstrated role as a transcriptional regulator in S. Typhimurium. Therefore we cloned and transferred the S. Typhimurium marT-fidL operon into S. Typhi and confirmed that invasion of monocytes was dramatically decreased. Finally, our findings suggest that the genomic and functional differences between SPI-3 sequences have implications in the host specificity of Typhi and Typhimurium serovars

Evaluación de producto DPX-QGU42 SE (300 g Famoxadone + 30 g QGU 42 / L) en el control de tizón temprano (Alternaria solani) en el cultivo de la papa (Solanum tuberosum).

45 p.La papa (solanum tuberosum), es uno de los cultivos más fáciles de trabajar y está presente en todo el mundo. A pesar de su sencillez, este, es uno de los cultivos que más destacan, en cuanto a sus propiedades como alimento y cultivo de primera línea en el combate del hambre, en los países pobres y subdesarrollados. En nuestro país, este cultivo es uno de los más importantes para la Agricultura Familiar Campesina, esta maneja aproximadamente el 70% de la producción nacional. De acuerdo a estos alcances, es primordial evaluar alternativas de manejo de las diversas patologías que afectan su desarrollo. Una de las enfermedades más importantes que atacan al cultivo de la papa es Tizón temprano, enfermedad producida por el hongo Alternaria solani, el cual se desarrolla en todos los lugares de producción de papa, como también en nuestro país, el cual puede generar grandes pérdidas, afectando el rendimiento y calidad del producto final En este estudio se evaluó a nivel de campo la efectividad del producto químico DPX – QGU 42 SE, en cuanto al efecto que produce este, sobre la incidencia y severidad de esta enfermedad, en el cultivo de papa. Este producto esta formulado en base a los ingredientes activos Famoxadone + QGU 42 SE (Producto en desarrollo perteneciente a la empresa DuPont), esta fue comparada con los productos que contenían los ingredientes activos Famoxadone, Picoxystrobin y Boscalid. El producto DPX – QGU42 SE, demostró al final de este ensayo ser una formulación que entrega excelentes resultados en cuanto a la reducción de la enfermedad Tizón temprano, cuyo comportamiento es similar a las demás alternativas utilizadas en este estudio:/ABSTRACT: The potato (Solanum tuberosum), is one of the easiest crops to work and it is present worldwide. Despite its simplicity, this is one of the most important crops in terms of their properties as food and it is in the first line as a crop to combat hunger and poverty in underdeveloped countries. In Chile, constitutes one of the most important crops for small farmers which concentrate about 70% of the national production. According to these outcomes, it seems important to evaluate new control alternatives for diseases that affect their development.One of the most important pathologies that infect potato crop it is early blight, a disease caused by the fungus Alternaria solani, which occurs wherever potato is grown, as well as in our country, generating important losses, affecting the yield and quality of the final product. The purpose of this study it was to evaluate the effectiveness at field level of the fungicide DPX - QGU 42 SE, in the control of this disease, measured as incidence and severity of early blight in a potato crop. This product, formulated on the active ingredients Famoxadone + QGU 42 SE (DuPont), was compared to other fungicides containing as active ingredients famoxadone, Picoxystrobin and boscalid. DPX - QGU42 SE, according to the results obtained in this assay, constitutes a good control alternative in terms of early blight incidence and severity reduction, being similar to the other alternatives used in this stud

Significados que le atribuyen un grupo de trabajadoras sexuales pertenecientes a la agrupación Transfemenina Traves en la comuna de Concepción en torno a la organización social como ocupación colectiva desde una mirada de género y patriarcado

Tesis (Terapeuta Ocupacional)En la siguiente investigación se trabajó con una agrupación de mujeres transexuales que ejercen el trabajo sexual. El objetivo principal de este estudio fue conocer y entender los significados de esta organización social como una ocupación colectiva, desde una mirada de género y patriarcado que le atribuye la agrupación Transfemenina Traves de Concepción. Este estudio se realizó porque no existen investigaciones desde la Terapia Ocupacional que aborden las temáticas del trabajo sexual desde una perspectiva social, sino que las investigaciones encontradas sólo se enfocan en la funcionalidad y no en las problemáticas expresadas desde las mismas mujeres que ejercen el trabajo sexual. En el presente trabajo, se pudo evidenciar cómo el sistema patriarcal influye en la cotidianidad de las trabajadoras sexuales debido al estigma y prejuicios existentes hacia ellas, provocando un malestar psicosocial en las integrantes de la agrupación. El principal resultado de la investigación fue entender que la agrupación Transfemenina Traves se convirtió en una ocupación colectiva, ya que las participantes se organizaron bajo un mismo objetivo para lograr el bienestar psicosocial, a pesar de que existen componentes socioculturales perjudiciales para ellas. Este trabajo se basó en el método cualitativo, ya que en el estudio de la agrupación se consideraron sus cualidades y características. Con esta metodología se enfatizó la subjetividad de las integrantes y el significado que éstas le atribuyen a la forma que tienen de organizarse dentro de la agrupación. Con el objetivo de dar coherencia con la metodología cualitativa, se utilizaron entrevistas semiestructuradas y observación de los miembros.In the following research, we worked with a group of transsexual women who practice sex work. The main objective of this work was to know and understand the meaning of a social organization as a collective occupation from a gender and patriarchal perspective, attributed by the group “Transfemenina Traves” from the city of Concepción. This study was conducted because of the nonexistence of research in the Occupational Therapy field addressing the issues of sex work from a social perspective. Past researches only focused on the functionality and not on the problems concerning the women performing sex work. This investigation presents evidence how the patriarchal system influences the daily life of the sex workers due to the stigma and prejudices existing in the society, causing a psychosocial discomfort in the members of the group. The main result of this research was to understand that the group “Transfemenina Traves” became a collective occupation, because the members were organized under a same objective with the aim to achieve a psychosocial wellbeing, even though the sociocultural components harming them. This work was based on a qualitative method, meaning that while studying the group, their qualities and characteristics were considered. With this methodology, the subjectivity of each member was emphasized and the meaning attributed by them to the way they have to organize inside the group. In order of coherence with the qualitative methodology, semistructured interviews and observation of the members were use

Extracorporeal membrane oxygenation improves survival in a novel 24-hour pig model of severe acute respiratory distress syndrome

Indexación: Web of Science; Pub Med CentralExtracorporeal membrane oxygenation (ECMO) is increasingly being used to treat severe acute respiratory distress syndrome (ARDS). However, there is limited clinical evidence about how to optimize the technique. Experimental research can provide an alternative to fill the actual knowledge gap. The purpose of the present study was to develop and validate an animal model of acute lung injury (ALI) which resembled severe ARDS, and which could be successfully supported with ECMO. Eighteen pigs were randomly allocated into three groups: sham, ALI, and ALI + ECMO. ALI was induced by a double-hit consisting in repeated saline lavage followed by a 2-hour period of injurious ventilation. All animals were followed up to 24 hours while being ventilated with conventional ventilation (tidal volume 10 ml/kg). The lung injury model resulted in severe hypoxemia, increased airway pressures, pulmonary hypertension, and altered alveolar membrane barrier function, as indicated by an increased protein concentration in bronchoalveolar fluid, and increased wet/dry lung weight ratio. Histologic examination revealed severe diffuse alveolar damage, characteristic of ARDS. Veno-venous ECMO was started at the end of lung injury induction with a flow > 60 ml/kg/min resulting in rapid reversal of hypoxemia and pulmonary hypertension. Mortality was 0, 66.6 and 16.6% in the SHAM, ALI and ALI + ECMO groups, respectively (p < 0.05). This is a novel clinically relevant animal model that can be used to optimize the approach to ECMO and foster translational research in extracorporeal lung support.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4931177

Specific and non-specific effects of Mycobacterium bovis BCG vaccination in dairy calves

Bovine tuberculosis (bTB) is a chronic disease mainly caused by Mycobacterium bovis, a zoonotic pathogen with economic significance as it leads to reduced milk and meat production, and high costs for control measures. The Bacillus Calmette-Guérin (BCG) vaccine, primarily used to prevent tuberculosis in humans, has also been studied for controlling bTB. While showing effectiveness in preventing M. bovis infection and disease in cattle, the BCG vaccine can induce non-specific effects on the immune system, enhancing responses to infections caused by unrelated pathogens, and also having non-specific effects on lactation. The aim of this study is to describe both the specific and non-specific effects of BCG vaccination in calves from a commercial dairy herd in central Chile. Diagnosis of M. bovis infection was performed through the IFNγ release assay (IGRA) using ESAT6/CFP-10 and Rv3615c antigens. The records of milk production, somatic cell count (SCC), clinical mastitis (CM) and retained placenta (RP) during the first lactation were compared between vaccinated and non-vaccinated animals. The breed (Holstein Friesian [HF] v/s HF × Swedish Red crossbred [HFSR]) and the season (warm v/s cold) were also analyzed as categorical explanatory variables. Results of IGRA showed significant differences between vaccinated and control groups, indicating a vaccine efficacy of 58.5% at 18 months post vaccination in HFSR crossbred animals. Although milk production did not vary, SCC and CM showed differences between groups, associated to the breed and the season, respectively. When analyzing CM and RP as a whole entity of disease, BCG showed protection in all but the cold season variables. Overall, the BCG vaccine induced protective specific and non-specific effects on health parameters, which may be influenced by the breed of animals and the season. These results provide new features of BCG protection, supporting initiatives for its implementation as a complementary tool in bTB control