ABSTRACT
Fargesia nitida is a cold-resistant evergreen bamboo and is a pioneer plant in the secondary succession after the native trees were destroyed in the eastern Tibetan Plateau. However, little is known about the effects of this plant on soil conditions and about its microbiomes. Aiming at learning the interactions among the soil characteristics, the plants and the microbes in relation to the plant succession, a study on cultivated microbes associated with the rhizocompartments of F. nitida was performed in the present study to reveal the preference of this plant to the root associated microbes, in comparison with that associated with the successive spruce (Picea asperata Mast.) trees. The results demonstrated that growth of F. nitida could improve the soil nutrient contents, especially increasing total nitrogen, NH4+-N, total carbon, and microbial biomass carbon, and maintained more soil bacteria than the successive spruce trees. Based upon the study of F. nitida root-associated cultivated microbial community, the nutrient improvement in F. nitida growing soils might be from the root endophytic bacteria, which presented greater abundance (3.8, 1.7, and 12.6 folds) than that of bacteria in its rhizosphere, root zone soil, and spruce root zone soil, respectively. Pseudomonas members, especially species related to P. baetica and P. vancouverensis, were strongly selected by F. nitida as root endophytes.
ABSTRACT
Introducción: Durante la pandemia por influenza A(H1N1), Chile alcanzó una de las tasas de casos más alta del mundo. Nuestro hospital recibió numerosos afectados el 2009 y 2010. Evaluamos el impacto de ventilación en posición prono (VPP) extendida, en las variables respiratorias de pacientes con SDRA grave secundario a influenza, y comparamos estos resultados con los obtenidos en otras series de VPP. Métodos: Estudio prospectivo, intervencional en UCI. Los pacientes recibieron oseltamivir y antibióticos y fueron manejados según protocolos (ventilatorio y no ventilatorio). Aquellos con criterios de SDRA grave fueron pronados hasta un índice de oxigenación <10. Se registraron parámetros de intercambio gaseoso, ventilatorios y desenlaces clínicos. Resultados: 12 pacientes con SDRA grave (edad 46+/-12 años, 7 hombres, APACHE II 17+/-6, SOFA 9+/-3) requirieron VPP, que se instauró a las 14(7-39) horas de ventilación mecánica (VM) y se mantuvo por 72(54-96) horas. Ningún paciente experimentó complicaciones mayores. La PaO2:FiO2 mejoró de 82(63-101) mmHg a 145(138-223) mmHg, (p<0.001). El tiempo en VM fue 20+/-13 días y en UCI 22+/-13 días. La mortalidad hospitalaria fue 25 por ciento y no cambió en el seguimiento de más de 8 meses. Este comportamiento con VPP fue similar al observado en otras series de SDRA grave. Conclusión: Los resultados obtenidos sugieren que la VPP resultó segura y se asoció a mejoría del intercambio gaseoso en pacientes con SDRA por influenza A(H1N1). Aunque el número reducido de pacientes no permite sacar mayores conclusiones, la VPP extendida podría ser de utilidad en los casos más graves causados por esta nueva influenza.
Introduction: During pandemic for influenza A(H1N1), Chile achieved one of the highest rates of infection worldwide. On 2009 and 2010, our hospital received a large number of infected patients. We evaluated the impact of extended prone position ventilation (PPV) on respiratory variables from severe ARDS patients secondary to this influenza. We also compared these results with those obtained with PPV in other series. Methods: Prospective, interventional study, performed in a mixed-ICU. Patients received oseltamivir and antibiotics, and were treated according to protocols (ventilatory and non-ventilatory). Severe ARDS patients were proned until oxygenation index was < 10. Oxygen exchange, ventilatory parameters and clinical outcomes were registered. Results: 12 severe ARDS patients (46+/-12 y.o., 7 men, APACHE II 17+/-6, SOFA 9+/-3) required PPV, which was started 14(7-39) hours after mechanical ventilation (MV) initiation, and it was maintained for 72(54-96) straight hours. No major complication was described. Three patients needed two periods of PPV. PaO2:FiO2 improved significantly with PPV from 82(63-101) mmHg to 145(138-223) mmHg, (p<0.001). Time on MV was 20+/-13 days, and LOS in UCI was 22+/-13 days. Hospital mortality was25 percent and remained unchanged for at least 8 month of follow-up. PPV had the same effect than in other severe ARDS series. Conclusion: Our results suggest PPV is safe and it was associated with improvement in oxygen exchange in ARDS secondary to A(H1N1) influenza. Although the small number of patients does not allow drawing any major conclusion, we believe PPV can be useful to treat severe ARDS cases due to influenza infection.