Clinical and genetic basis of hypertensive nephrosclerosis. NEFROSEN Study

Justificación: Se conoce como nefroesclerosis la enfermedad renal crónica (ERC) que complica la hipertensión arterial (HTA) esencial. La ausencia de correlación entre el control de la HTA y la progresión a ERC terminal sugiere la existencia de una enfermedad intrínseca y primitiva. Recientemente se ha asociado con polimorfismos del gen MYH9 en individuos afroamericanos. El objetivo del trabajo que presentamos es determinar si algún polimorfismo de dicho gen se relaciona en raza caucásica con la asociación de HTA esencial y nefroesclerosis y, además, conocer los marcadores de progresión a ERC terminal. Será un estudio retrospectivo que comparará a pacientes con nefroesclerosis frente a pacientes con HTA esencial sin enfermedad renal y, además, se incluirán pacientes con nefroesclerosis y progresión de la enfermedad renal frente a los que se mantienen estables. Métodos: Entre octubre de 2009 y octubre de 2010 se incluirán 500 pacientes con ERC (estadios 3-5) atribuida a nefroesclerosis según criterios clínicos habituales, y 300 pacientes afectados de HTA esencial (FGe >60 ml/min/1,73 m2 ; microalbuminuria <300 mg/g). Para el estudio genético también se incluirán 200 controles sanos de población general. Habrá dos cortes del estudio, la primera visita en el hospital y la visita final (en estadio 5 el inicio del tratamiento sustitutivo constituirá el final del seguimiento). Se registrarán datos clínicos y analíticos, y se recogerán muestras de sangre para el estudio genético. Discusión: Nuestro estudio, con la doble vertiente genética y clínica, tratará de determinar si en la raza caucásica existe relación entre el diagnóstico de nefroesclerosis y el gen MYH9, y estudiará, además, los posibles marcadores de progresión.Background: Hypertensive nephrosclerosis is a chronic kidney disease (CKD) associated to essential hypertension. The lack of correlation between strict control of hypertension and progression of CKD suggests an intrinsic and primary disease. New evidence suggests that MYH9 gene alterations are associated with nephrosclerosis in African Americans. The aim of this study is to investigate whether a polymorphism of MYH9 in Caucasians is linked to the association of essential hypertension and nephrosclerosis. The secondary objective is to identify the clinical risk factors of progression to end-stage renal disease (ESRD). This is a retrospective study that will compare patients with nephrosclerosis versus essential hypertensives without renal disease, and also patients with nephrosclerosis and impaired renal function versus those that are stable. Methods: Between October 2009 and October 2010, 500 patients stages 3-5 CKD attributed to nephrosclerosis according to usual clinical criteria, and 300 essential hypertensives (eGFR > 60 mL/min/1.73m2 ; microalbuminuria study. There will be two sections of the study, first and final visit to the clinic (stage 5, the start of replacement therapy will be the end of follow-up). Clinical and laboratory data will be recorded, and blood samples will be collected. Discussion: Our study will seek to determine if there exists a relationship between the diagnosis of nephrosclerosis and MYH9 gene in the Caucasian race, and to study possible risk factors for progression to ESRD, on both clinical and genetic basis

Resistencia antimicrobiana de Streptococcus spp. aislado de mastitis clínica en tambos de la Región Mar y Sierras, Argentina

Streptococcus dysgalactiae, and S. uberis are the most prevalent Streptococcus species isolated from clinical\nmastitis. Most of all antimicrobials administered on dairy farms are for treating mastitis. Considering that antimicrobial resistance can vary between regions, it is crucial to monitor the susceptibility of microorganisms to antimicrobials used. Particularly, it is known that clinical mastitis caused by S. uberis frequently do not respond to antimicrobial therapy and that this pathogen causes recurrent infections. The general aim was to evaluate the antimicrobial susceptibility of S. uberis and S. dysgalactiae isolates from 23 dairy farms located in the Cuenca Mar y Sierras, Argentina, for the main antimicrobials used in this region, and characterize the dairy farms from which the pathogens come. A total of 39 S. uberis and S. dysgalactiae strains were isolated and tested for susceptibility to 5 antibiotics using a disc diffusion method. Results showed frequencies of AMR to tetracycline of 26 %, pirlimycin 18 %, rifaximin 15 %, penicillin 8 %, and kanamycin 5 %, the detection of resistance to all the antibiotics in S. uberis, and that the multi-resistant isolates belonged to dairy farms that carry out antimicrobial treatments in an empirical manner.Fil: Bottini, E. CONICET. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Investigación Veterinaria de Tandil (CIVETAN). Laboratorio de Microbiología Clínica y Experimental. Buenos Aires, ArgentinaFil: Gerez, G. CONICET. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Investigación Veterinaria de Tandil (CIVETAN). Laboratorio de Inmunoquímica y Biotecnología. Buenos Aires, ArgentinaFil: Hernandez, L.B. CONICET. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Investigación Veterinaria de Tandil (CIVETAN). Laboratorio de Inmunoquímica y Biotecnología. Buenos Aires, ArgentinaFil: Monteavaro, C. CONICET. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Investigación Veterinaria de Tandil (CIVETAN). Laboratorio de Microbiología Clínica y Experimental. Buenos Aires, ArgentinaFil: Sanso, A.M. CONICET. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Investigación Veterinaria de Tandil (CIVETAN). Laboratorio de Inmunoquímica y Biotecnología. Buenos Aires, ArgentinaStreptococcus dysgalactiae y S. uberis son las especies de Streptococcus más frecuentemente aisladas de mastitis clínica. La mayoría de los antimicrobianos administrados en los tambos se usan para tratar infecciones intramamarias. Teniendo en cuenta que la resistencia a los antimicrobianos puede variar entre regiones, es crucial monitorear la susceptibilidad de los microorganismos a los antimicrobianos utilizados. En particular, se sabe que la mastitis clínica causada por S. uberis, con frecuencia, no responde fácilmente a la terapia antimicrobiana y, que este patógeno tiende a causar infecciones recurrentes. El objetivo fue evaluar la susceptibilidad antimicrobiana de aislamientos de S. uberis y de S. dysgalactiae obtenidos en 23 tambos de la Cuenca Mar y Sierras, Argentina, y caracterizar los tambos de donde provienen. Se aislaron 39 cepas de S. uberis y S. dysgalactiae y se analizó la susceptibilidad a 5 antibióticos mayormente utilizados en la región mediante difusión en disco. Los resultados mostraron frecuencias de resistencia a tetraciclina de 26 %, pirlimicina 18 %, rifaximina 15 %, penicilina 8 % y kanamicina 5 %, la detección de resistencia a todos los antibióticos en S. uberis y que los aislamientos multirresistentes pertenecieron a tambos que realizan tratamientos antimicrobianos de manera empírica

Variations in the carbohydrate expression pattern and in lesions of the uterine horns of BALB/c mice infected with different Tritrichomonas foetus isolates

Bovine tritrichomonosis, a sexually transmitted disease caused by the protozoan Tritrichomonas foetus, is characterized by producing reproductive alterations in cattle. Carbohydrates on the surface of the uterine epithelium are involved in the process of adhesion and colonization of the protozoan. The murine model has proved to be an inexpensive, practical and representative alternative to study the lesions produced in the natural host. For this work, during the first stage, 6–8 week old female BALB/c mice were inoculated with 24 different T. foetus isolates in order to classify them according to their pathogenicity. Then, seven isolates were selected and processed with lectin histochemistry to determine if the differences in pathogenicity corresponded to the changes found in the uterine carbohydrate expression pattern. In this work, we demonstrate the differences in the expression of the carbohydrate pattern between infected and uninfected mice. In addition, within the group of infected mice, differences were found in the degree of pathogenicity of the isolates, thus evidencing their biological variability.Fil: Falcón, Juan Esteban. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Laboratorio de Histología y Embriología Descriptiva, Experimental y Comparada (LHYEDEC); . Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Rivero, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnología y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnología y Desarrollo; ArgentinaFil: Doumecq, María Laura. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Soto, P.. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Monteavaro, C. E.. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Woudwyk, Mariana Andrea. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Laboratorio de Histología y Embriología Descriptiva, Experimental y Comparada (LHYEDEC); . Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Barbeito, Claudio Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Laboratorio de Histología y Embriología Descriptiva, Experimental y Comparada (LHYEDEC)

Experimentally induced intravaginal Tritrichomonas foetus infection in a mouse model Infecção experimental intravaginal com Tritricho-monas foetus em modelo camundongo

The interest to develop research on the host-parasite relationship in bovine tritrichomonosis has accomplished the use of experimental models alternative to cattle. The BALB/c mouse became the most appropriate species susceptible to vaginal Tritrichomonas foetus infection requiring previous estrogenization. For the need of an experimental model without persistent estrogenization and with normal estrous cycles, the establishment and persistence of vaginal infection on BALB/c mouse with different concentrations of T. foetus in two experimental groups was evaluated. Group A was treated with 5mg of b-estradiol 3-benzoate to synchronize the estrous, 48 hours before the T. foetus vaginal inoculation, and Group B was inoculated in natural estrus. At 5-7 days after treatment, estrogenic effect decreased allowing all animals to cycle regularly during the experiment. From the first week post-infection, samples of vaginal mucus were taken from all animals during 34 weeks, in order to evaluate the course of infection and the stage of the estrus cycle. Group A showed 93.6% of infected animals, and Group B showed 38%. Different doses of T. foetus were assayed to establish the vaginal infection, with a persistence of 34 weeks. Although different behavior was observed in each subgroup belonging to either Group A or Group B, there were no significant differences among the infecting doses used. The b-estradiol 3-benzoate treatment had a favorable effect on the establishment of the infection (P<0.0001), but it did not influence its persistence (P=0.1097). According to the results, an experimental mouse model is presented, appropriate for further studies on mechanisms of pathogenicity, immune response, protective evaluation of immunogen and therapeutic effect of drugs.<br>A necessidade de esclarecer a relação agente-hospedeiro na tricomoníase bovina deu motivo para o uso de modelos experimentais alternativos ao bovino. O camundongo BALB/c resultou como espécie mais adequada para a infeção vaginal com Tritrichomonas foetus, requerendo uma estrogenização prévia. Visando a necessidade de um modelo experimental sem estrogenização persistente e com ciclos estrais normais, foi avaliada a instalação e persistência da infeção vaginal no camundongo BALB/c com diferentes quantidades de T. foetus, em dois grupos experimentais. O Grupo A foi tratado com 5µg de 3-benzoato de beta estradiol, para sincronizar o estro, 48 h antes da inoculação vaginal com T. foetus, e o Grupo B foi inoculado durante o estro natural. O efeito do 3-benzoato de beta estradiol decresceu gradualmente. A totalidade dos animais ciclaram regularmente após 5-7 dias pós-tratamento. Após a primeira semana pós-infecção, todos os animais foram amostrados durante 34 semanas, para avaliar o andamento da infeção vaginal e o estádio de cío. O Grupo A apresentou 93,6% de animais infetados e o Grupo B 38%. Com diferentes dosagens de T. foetus se obteve a instalação e persistência da infecção vaginal durante 34 semanas. Embora tenham-se registrados diferentes comportamentos entre cada um dos lotes dos Grupos A e B, não houveram diferenças significativas entre as doses infectantes. O tratamento com 3-benzoato de beta estradiol teve efeito favorável na instalação da infecção (P<0,0001), porém não teve influência na persistência (P= 0,1097). Em função dos resultados obtidos, apresenta-se um modelo experimental em camundongo, adequado para aprofundar estudos sobre mecanismos de patogenicidade, resposta imune, avaliação protetora de imunógenos e o efeito terapêutico de fármacos

Emerging biodegradable materials: starch- and protein-based bio-nanocomposites

This article provides a broad overview on the natural polymer-based bio-nanocomposite properties, processing and application. Bio-nanocomposites prepared with natural biopolymers, such as starch and protein, can be formed using a melt intercalation or a solvent intercalation method. Incorporation of layered silicates into the biopolymer matrices results in improved mechanical properties, water vapor barrier properties, and thermal stability of the resulting bio-nanocomposites without sacrificing biodegradability due to their nanometer size dispersion. Consequently, even though natural polymer-based bio-nanocomposite is in its infancy, it has a huge potential in the future