205 research outputs found
Identification of three novel Toxoplasma gondii rhoptry proteins
The rhoptries are key secretory organelles from apicomplexan parasites that contain proteins involved in invasion and modulation of the host cell. Some rhoptry proteins are restricted to the posterior bulb (ROPs) and others to the anterior neck (RONs). As many rhoptry proteins have been shown to be key players in Toxoplasma invasion and virulence, it is important to identify, understand and characterise the biological function of the components of the rhoptries. In this report, we identified putative novel rhoptry genes by identifying Toxoplasma genes with similar cyclical expression profiles as known rhoptry protein encoding genes. Using this approach we identified two new rhoptry bulb (ROP47 and ROP48) and one new rhoptry neck protein (RON12). ROP47 is secreted and traffics to the host cell nucleus, RON12 was not detected at the moving junction during invasion. Deletion of ROP47 or ROP48 in a type II strain did not show major influence in in vitro growth or virulence in mice.United States. National Institutes of Health (R01-AI080621
In Vivo Transcriptional Profiling of Listeria monocytogenes and Mutagenesis Identify New Virulence Factors Involved in Infection
Listeria monocytogenes is a human intracellular pathogen able to colonize host tissues after ingestion of contaminated food, causing severe invasive infections. In order to gain a better understanding of the nature of host–pathogen interactions, we studied the L. monocytogenes genome expression during mouse infection. In the spleen of infected mice, ≈20% of the Listeria genome is differentially expressed, essentially through gene activation, as compared to exponential growth in rich broth medium. Data presented here show that, during infection, Listeria is in an active multiplication phase, as revealed by the high expression of genes involved in replication, cell division and multiplication. In vivo bacterial growth requires increased expression of genes involved in adaptation of the bacterial metabolism and stress responses, in particular to oxidative stress. Listeria interaction with its host induces cell wall metabolism and surface expression of virulence factors. During infection, L. monocytogenes also activates subversion mechanisms of host defenses, including resistance to cationic peptides, peptidoglycan modifications and release of muramyl peptides. We show that the in vivo differential expression of the Listeria genome is coordinated by a complex regulatory network, with a central role for the PrfA-SigB interplay. In particular, L. monocytogenes up regulates in vivo the two major virulence regulators, PrfA and VirR, and their downstream effectors. Mutagenesis of in vivo induced genes allowed the identification of novel L. monocytogenes virulence factors, including an LPXTG surface protein, suggesting a role for S-layer glycoproteins and for cadmium efflux system in Listeria virulence
Glutathionylation of Pea Chloroplast 2-Cys Prx and Mitochondrial Prx IIF Affects Their Structure and Peroxidase Activity and Sulfiredoxin Deglutathionylates Only the 2-Cys Prx
Together with thioredoxins (Trxs), plant peroxiredoxins (Prxs), and sulfiredoxins (Srxs) are involved in antioxidant defense and redox signaling, while their regulation by post-translational modifications (PTMs) is increasingly regarded as a key component for the transduction of the bioactivity of reactive oxygen and nitrogen species. Among these PTMs, S-glutathionylation is considered a protective mechanism against overoxidation, it also modulates protein activity and allows signaling. This study explores the glutathionylation of recombinant chloroplastic 2-Cys Prx and mitochondrial Prx IIF from Pisum sativum. Glutathionylation of the decameric form of 2-Cys Prx produced a change in the elution volume after FPLC chromatography and converted it to its dimeric glutathionylated form, while Prx IIF in its reduced dimeric form was glutathionylated without changing its oligomeric state. Mass spectrometry demonstrated that oxidized glutathione (GSSG) can glutathionylate resolving cysteine (Cys174), but not the peroxidatic equivalent (Cys52), in 2-Cys Prx. In contrast, GSSG was able to glutathionylate both peroxidatic (Cys59) and resolving (Cys84) cysteine in Prx IIF. Glutathionylation was seen to be dependent on the GSH/GSSG ratio, although the exact effect on the 2-Cys Prx and Prx IIF proteins differed. However, the glutathionylation provoked a similar decrease in the peroxidase activity of both peroxiredoxins. Despite growing evidence of the importance of post-translational modifications, little is known about the enzymatic systems that specifically regulate the reversal of this modification. In the present work, sulfiredoxin from P. sativum was seen to be able to deglutathionylate pea 2-Cys Prx but not pea Prx IIF. Redox changes during plant development and the response to stress influence glutathionylation/deglutathionylation processes, which may represent an important event through the modulation of peroxiredoxin and sulfiredoxin proteins.This research was supported by MICINN, Spain (BFU2014-52452-P co-financed by FEDER) and Seneca Foundation, Murcia, Spain (Excellence Group 19876/GERM/15).Peer reviewedPeer Reviewe
LA EDUCACIÓN DE LA SEXUALIDAD EN LA FORMACIÓN DE LOS ESTUDIANTES DE LAS ESCUELAS PEDAGÓGICAS
El presente artículo visibiliza una problemática aún presente en la sociedad, a pesar de que cada día se promueven más la aceptación y el respeto a la diversidad sexual. Con la aplicación de métodos como la observación, la entrevista grupal y la encuesta se constató la existencia de conductas y manifestaciones de rechazo y de violencia hacia los estudiantes con orientación sexual homosexual en la Escuela Pedagógica José Martí de la provincia Holguín. Esta contradicción entre lo que desde la teoría está establecido a nivel nacional y lo que realmente está sucediendo en la práctica en el contexto educativo nos motivó a proponer la realización de una campaña de comunicación para promover la aceptación de la diversidad sexual de dichos estudiantes. Para su eficaz puesta en práctica ofrecimos orientaciones metodológicas a los profesores de fácil comprensión y aplicación
La prevención de la violencia escolar, una necesidad en la formación de maestros primarios (Original)
The pretensions of peace, justice and equity among human beings are constantly threatened in their achievement by a current social problem in contemporary society: violence, whose presence in the school space can not be unknown because of the harmful influence it exerts on health and education. It belongs to the teachers to conceive the necessary ways to prevent the appearance of violence manifestations. The research that is presented approaches the theoretical framework of the understanding of the educational process of the Primary Teacher Training School in the prevention of school violence, as well as the singular theoretical elements of the aforementioned process. In this sense, an educational strategy for the prevention of school violence is elaborated from the systemic approach. The studied population includes the 1st year students of the Primary Teachers specialty. This work provides the necessary methodological tools to prevent school violence from the work of the teacher.Las pretensiones de paz, justicia y equidad entre los seres humanos se ven constantemente amenazadas en su consecución por un problema social vigente en la sociedad contemporánea: la violencia, cuya presencia en el espacio escolar no puede ser desconocida por la influencia dañina que ejerce sobre la salud y la educación. Pertenece a los profesores concebir las vías necesarias para prevenir la aparición de manifestaciones violencia. La investigación que se presenta aborda como marco teórico referencial la comprensión del proceso educativo de la Escuela Formadora de Maestros Primarios en la prevención de la violencia escolar, así como los elementos teóricos singulares del proceso aludido. En este sentido se modela una estrategia educativa para la prevención de la violencia escolar, elaborada desde el enfoque sistémico. La población estudiada comprende a los alumnos de 1er año de la especialidad Maestros Primarios. Este trabajo le brinda las herramientas metodológicas necesarias para prevenir la violencia escolar desde la labor del profesor
Dermoid Cyst in the Anterior Fontanel: Case Report
Introduction: Dermoid cysts in the anterior fontanel are rare lesions, problems around 0.1–0.5% of all cranial tumors. It originated during the early stages of development and derived from embryonic epithelial tissue located along the midline. CT and NMR studies are of choice to rule out intracranial extension. They are diagnosed and treated with surgery in childhood. In this article, a review of the literature on this pathology is performed and a clinical case is reported in order to show the results of imaging studies in the Dermoid Cyst in childhood. Case Presentation: Four-month-old female infant with Dermoid Cyst in the Anterior Fontanelle, without neurological compromise who was once a surgery. The surgical piece affected uniform, encapsulated, mobile, soft lesion with clear content. The obstetric history, clinical data, physical examination, imaging and histopathological studies confirmed the diagnosis of Dermoid Cyst, the patient’s postoperative evolution is satisfactory, currently undergoing follow-up by Neuropediatrics. Conclusion: in simple pediatric patients with Dermoid Cyst in the anterior Fontanelle, simple Computerized Axial Skull Tomography is very useful for its diagnosis, as well as the performance of surgical treatment and postoperative follow- up for a favorable evolution and better prognosis.
Keywords: dermoid cyst, anterior fontanelle, congenital inclusion cyst, case report.
RESUMEN
Introducción: La frecuencia de presentación del Quiste Dermoide en fontanela anterior es muy baja y se desarrollan en la etapa embrionaria de la vida en la que el tejido embrionario de la línea media dá lugar a su formación. Los estudios de TAC y RMN son de elección para descartar la extensión intracraneal. Se diagnostican y tratan con cirugía en la niñez. En este artículo se realiza una revisión de la literatura sobre esta patología y se relata un caso clínico con el objetivo de mostrar los resultados de estudios imagenológicos en el Quiste Dermoide en la infancia. Presentación de Caso: Lactante femenina de cuatro meses con Quiste Dermoide de la fontanela anterior sin complicaciones fue intervenida quirúrgicamente. Se realizó excéresis de lesión blanda, encapsulada y movible. Los antecedentes obstétricos, datos clínicos, examen físico, estudios imagenológicos e histopatológico confirmaron el diagnóstico de Quiste tipo Dermoide, la evolución posoperatoria de la paciente es satisfactoria, actualmente en seguimiento por Neuropediatría. Conclusiones: En pacientes pediátricos con Quiste Dermoide en la Fontanela anterior es de gran utilidad la Tomografía Axial Computarizada simple de Cráneo para su diagnóstico, así como, la realización de un tratamiento quirúrgico y el seguimiento postoperatorio para una favorable evolución y mejor pronóstico.
Palabras clave: quiste dermoide, fontanela anterior, quiste de inclusión congénita, informe de caso
Toxoplasma gondii Superinfection and Virulence during Secondary Infection Correlate with the Exact [ROP5 over ROP18] Allelic Combination
The intracellular parasite Toxoplasma gondii infects a wide variety of vertebrate species globally. Infection in most hosts causes a lifelong chronic infection and generates immunological memory responses that protect the host against new infections. In regions where the organism is endemic, multiple exposures to T. gondii likely occur with great frequency, yet little is known about the interaction between a chronically infected host and the parasite strains from these areas. A widely used model to explore secondary infection entails challenge of chronically infected or vaccinated mice with the highly virulent type I RH strain. Here, we show that although vaccinated or chronically infected C57BL/6 mice are protected against the type I RH strain, they are not protected against challenge with most strains prevalent in South America or another type I strain, GT1. Genetic and genomic analyses implicated the parasite-secreted rhoptry effectors ROP5 and ROP18, which antagonize the host’s gamma interferon-induced immunity-regulated GTPases (IRGs), as primary requirements for virulence during secondary infection. ROP5 and ROP18 promoted parasite superinfection in the brains of challenged survivors. We hypothesize that superinfection may be an important mechanism to generate T. gondii strain diversity, simply because two parasite strains would be present in a single meal consumed by the feline definitive host. Superinfection may drive the genetic diversity of Toxoplasma strains in South America, where most isolates are IRG resistant, compared to North America, where most strains are IRG susceptible and are derived from a few clonal lineages. In summary, ROP5 and ROP18 promote Toxoplasma virulence during reinfection
Preparación pedagógica de los profesores de la carrera de Licenciatura en Enfermería en la elaboración de instrumentos evaluativos
Introduction: the assessment of pedagogical training together with the development of teaching competences that should characterize the professors is a social demand of first order, which should be in agreement with the model of health professionals the current society requires. Objective: to characterize the pedagogical training of the Nursing-Specialty Professors in the design of evaluation instruments in the Republic of Venezuela during 2010. Methods: a descriptive and cross-sectional study was carried out comprising 20 professors who belonged to the Academic Committees (the target group and the sample coincided). Theoretical, empiric and statistical methods allowed the study of the problem. Results: the totality of professors polled had teaching experience, prevailing instructors, and 95% had attended to a pedagogy course or to courses of evaluation or quality of written-evaluation instruments, the majority were aware of the difficulties they presented in the design of the type of questions following the established requisites, in the selection of the type of questions according to the contents, and in the design of tables of contents. Conclusions: professors of Nursing Studies, despite their teaching experience, teaching rank and/or training courses passed, pedagogical preparation is required to design evaluation instruments in order to improve quality.Introducción: resulta una exigencia social de primer orden, en relación con los procesos formativos, valorar una capacitación pedagógica del claustro profesoral pensada en términos de las competencias docentes que tienen que caracterizar al profesor, para el desempeño de una docencia comprometida con el modelo profesional en salud que la sociedad actual exige. Objetivo: caracterizar la preparación pedagógica de los profesores de la carrera de Licenciatura en Enfermería en la elaboración de instrumentos evaluativos. República Bolivariana de Venezuela, 2010.Métodos: se realizó un estudio descriptivo, transversal, el universo coincide con la muestra y estuvo constituido por 20 profesores que conforman los Comités Académicos, en cuya ejecución se utilizaron métodos teóricos, empíricos y procedimientos estadísticos que permitieron el estudio del problema. Resultados: la totalidad de los profesores encuestados tenían experiencia docente, predominó la categoría docente de instructor, el 95% había recibido el curso de pedagogía y el curso de evaluación o calidad de instrumentos de evaluación escrita, la mayoría reconocen tener dificultades en los requisitos para la confección de los tipos de preguntas, en la selección del tipo de pregunta en función de los contenidos y en la elaboración de la tabla de contenidos. Conclusiones: los profesores de la carrera de Licenciatura en Enfermería a pesar de la experiencia, categoría docente y la superación recibida se requiere perfeccionar la preparación pedagógica en la elaboración de instrumentos evaluativos en función de mejorar la calidad
Pedagogical preparation for the Nursing-Specialty Professors in the design of evaluation instruments
Introducción: resulta una exigencia social de primer orden, en relación con los procesos formativos, valorar una capacitación pedagógica del claustro profesoral pensada en términos de las competencias docentes que tienen que caracterizar al profesor, para el desempeño de una docencia comprometida con el modelo profesional en salud que la sociedad actual exige. Objetivo: caracterizar la preparación pedagógica de los profesores de la carrera de Licenciatura en Enfermería en la elaboración de instrumentos evaluativos. República Bolivariana de Venezuela, 2010.Métodos: se realizó un estudio descriptivo, transversal, el universo coincide con la muestra y estuvo constituido por 20 profesores que conforman los Comités Académicos, en cuya ejecución se utilizaron métodos teóricos, empíricos y procedimientos estadísticos que permitieron el estudio del problema. Resultados: la totalidad de los profesores encuestados tenían experiencia docente, predominó la categoría docente de instructor, el 95% había recibido el curso de pedagogía y el curso de evaluación o calidad de instrumentos de evaluación escrita, la mayoría reconocen tener dificultades en los requisitos para la confección de los tipos de preguntas, en la selección del tipo de pregunta en función de los contenidos y en la elaboración de la tabla de contenidos. Conclusiones: los profesores de la carrera de Licenciatura en Enfermería a pesar de la experiencia, categoría docente y la superación recibida se requiere perfeccionar la preparación pedagógica en la elaboración de instrumentos evaluativos en función de mejorar la calidad.Introduction: the assessment of pedagogical training together with the development of teaching competences that should characterize the professors is a social demand of first order, which should be in agreement with the model of health professionals the current society requires. Objective: to characterize the pedagogical training of the Nursing-Specialty Professors in the design of evaluation instruments in the Republic of Venezuela during 2010. Methods: a descriptive and cross-sectional study was carried out comprising 20 professors who belonged to the Academic Committees (the target group and the sample coincided). Theoretical, empiric and statistical methods allowed the study of the problem. Results: the totality of professors polled had teaching experience, prevailing instructors, and 95% had attended to a pedagogy course or to courses of evaluation or quality of written-evaluation instruments, the majority were aware of the difficulties they presented in the design of the type of questions following the established requisites, in the selection of the type of questions according to the contents, and in the design of tables of contents. Conclusions: professors of Nursing Studies, despite their teaching experience, teaching rank and/or training courses passed, pedagogical preparation is required to design evaluation instruments in order to improve quality
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