In vivo and in vitro 31P-NMR Study of the Phosphate Transport and Polyphosphate Metabolism in Hebeloma cylindrosporum in Response to Plant Roots Signals.

We used in vivo and in vitro phosphorus-31 nuclear magnetic resonance (31P-NMR) spectroscopy to follow the change in transport, compartmentation and metabolism of phosphate in the ectomycorrhizal fungus Hebeloma cylindrosporum in response to root signals originating from host (Pinus pinaster) or non-host (Zea mays) plants. A device was developed for the in vivo studies allowing the circulation of a continuously oxygenated mineral solution in an NMR tube containing the mycelia. The in vitro studies were performed on fungal material after several consecutive treatment steps (freezing in liquid nitrogen; crushing with perchloric acid; elimination of perchloric acid; freeze-drying; dissolution in an appropriate liquid medium).

The host plant Pinus pinaster exerts specific effects on phosphate efflux and polyphosphate metabolism of the ectomycorrhizal fungus Hebeloma cylindrosporum: a radiotracer, cytological staining and 31 P NMR spectroscopy study.

Ectomycorrhizal (ECM) association can improve plant phosphorus (P) nutrition. Polyphosphates (polyP) synthesized in distant fungal cells after P uptake may contribute to P supply from the fungus to the host plant if they are hydrolyzed to phosphate in ECM roots then transferred to the host plant when required. In this study, we addressed this hypothesis for the ECM fungus Hebeloma cylindrosporum grown in vitro and incubated without plant or with host (Pinus pinaster) and non-host (Zea mays) plants, using an experimental system simulating the symbiotic interface. We used 32 P labelling to quantify P accumulation and P efflux and in vivo and in vitro nuclear magnetic resonance (NMR) spectroscopy and cytological staining to follow the fate of fungal polyP. Phosphate supply triggered a massive P accumulation as newly synthesized long-chain polyP in H. cylindrosporum if previously grown under P-deficient conditions. P efflux from H. cylindrosporum towards the roots was stimulated by both host and non-host plants. However, the host plant enhanced 32 P release compared with the non-host plant and specifically increased the proportion of short-chain polyP in the interacting mycelia. These results support the existence of specific host plant effects on fungal P metabolism able to provide P in the apoplast of ectomycorrhizal roots.

A Spanish-language patient safety questionnaire to measure medical and nursing students' attitudes and knowledge / Un cuestionario en espanol sobre seguridad del paciente para medir las actitudes y los conocimientos de los estudiantes de medicina y enfermería

OBJECTIVE: To design and validate a questionnaire for assessing attitudes and knowledge about patient safety using a sample of medical and nursing students undergoing clinical training in Spain and four countries in Latin America. METHODS: In this cross-sectional study, a literature review was carried out and total of 786 medical and nursing students were surveyed at eight universities from five countries (Chile, Colombia, El Salvador, Guatemala, and Spain) to develop and refine a Spanish-language questionnaire on knowledge and attitudes about patient safety. The scope of the questionnaire was based on five dimensions (factors) presented in studies related to patient safety culture found in PubMed and Scopus. Based on the five factors, 25 reactive items were developed. Composite reliability indexes and Cronbach's alpha statistics were estimatedfor each factor, and confirmatory factor analysis was conducted to assess validity. After a pilot test, the questionnaire was refined using confirmatory models, maximum-likelihood estimation, and the variance-covariance matrix (as input). Multiple linear regression models were used to confirm external validity, considering variables related to patient safety culture as dependent variables and the five factors as independent variables. RESULTS: The final instrument was a structured five-point Likert self-administered survey (the "Latino Student Patient Safety Questionnaire") consisting of 21 items grouped into five factors. Compound reliability indexes (Cronbach's alpha statistic) calculated for the five factors were about 0.7 or higher. The results of the multiple linear regression analyses indicated good model fit (goodness-of-fit index: 0.9). Item-total correlations were higher than 0.3 in all cases. The convergent-discriminant validity was adequate. CONCLUSIONS: The questionnaire designed and validated in this study assesses nursing and medical students' attitudes and knowledge about patient safety. This instrument could be used to indirectly evaluate whether or not students in health disciplines are acquiring and thus likely to put into practice the professional skills currently considered most appropriate for patient safety.

OBJETIVO: Diseñar y validar un cuestionario de evaluación de las actitudes y los conocimientos en materia de seguridad del paciente con una muestra de estudiantes de medicina y enfermería que reciben formación médica en Espana y en cuatro países de América Latina. MÉTODOS: En este estudio transversal se llevó a cabo una revisión bibliográfica y se encuestó a un total de 786 estudiantes de medicina y enfermería de ocho universidades de cinco países (Chile, Colombia, El Salvador, Espana y Guatemala) con objeto de elaborar y corregir un cuestionario en espanol sobre conocimientos y actitudes en materia de seguridad del paciente. El ámbito del cuestionario se basó en cinco dimensiones (factores) presentadas en estudios relacionados con la cultura de la seguridad del paciente encontrados en PubMed y Scopus. Con base en los cinco factores, se elaboraron 25 ítems reactivos. Se calcularon los índices de fiabilidad compuesta y alfa de Cronbach para cada factor, y se realizó un análisis factorial confirmatorio para evaluar la validez. Tras una prueba piloto se corrigió el cuestionario mediante modelos confirmatorios, el cálculo de la máxima probabilidad y la matriz de variancia-covariancia (como insumo). Se utilizaron modelos de regresión lineal múltiple para confirmar la validez externa, considerando las variables relacionadas con la cultura de seguridad del paciente como variables dependientes y los cinco factores como variables independientes. RESULTADOS: El instrumento final fue una encuesta autoadministrada mediante escala de Likert estructurada en cinco puntos ("Cuestionario de Seguridad del Paciente para Estudiantes Latinos"), que consta de 21 ítems agrupados en cinco factores. Los índices de fiabilidad compuesta (prueba estadística de alfa de Cronbach) calculados para los cinco factores fueron aproximadamente de 0,7 o superiores. Los resultados de los análisis de regresión lineal múltiple indicaron un buen ajuste del modelo (índice de bondad de ajuste: 0,9). Las correlaciones ítem-total fueron superiores a 0,3 en todos los casos. La validez convergente y discriminatoria fue adecuada. CONCLUSIONES: El cuestionario disenado y validado en este estudio evalúa las actitudes y los conocimientos de los estudiantes de enfermería y medicina en materia de seguridad del paciente. Este instrumento podría utilizarse para evaluar indirectamente si los estudiantes de disciplinas de la salud están adquiriendo, y por lo tanto, es probable que pongan en práctica, las habilidades profesionales consideradas actualmente como más apropiadas para la seguridad del paciente.