Non-invasive positive pressure ventilation in pneumonia outside Intensive Care Unit: An Italian multicenter observational study.

BACKGROUND AND OBJECTIVE: Non-Invasive Ventilation (NIV) represents a standard of care to treat some acute respiratory failure (ARF). Data on its use in pneumonia are lacking, especially in a setting outside the Intensive Care Unit (ICU). The aims of this study were to evaluate the use of NIV in ARF due to pneumonia outside the ICU, and to identify risk factors for in-hospital mortality. METHODS: Prospective, observational study performed in 19 centers in Italy. Patients with ARF due to pneumonia treated outside the ICU with either continuous positive airway pressure (CPAP) or noninvasive positive pressure ventilation (NPPV) were enrolled over a period of at least 3 consecutive months in 2013. Independent factors related to in-hospital mortality were evaluated. RESULTS: Among the 347 patients enrolled, CPAP was applied as first treatment in 176 (50.7%) patients,NPPV in 171 (49.3%). The NPPV compared with CPAP group showed a significant higher PaCO2 (55 [47-78] vs 37 [32-43] mmHg, p < 0.001), a lower arterial pH (7.30 [7.21-7.37] vs 7.43 [7.35-7.47], p < 0.001), higher HCO3- (28 [24-33] vs 24 [21-27] mmol/L, p < 0.001). De-novo ARF was more prevalent in CPAP group than in NPPV group (86/176 vs 31/171 patients,p < 0.001). In-hospital mortality was 23% (83/347). Do Not Intubate (DNI) order and Charlson Comorbidity Index (CCI) ≥3 were independent risk factors for in-hospital mortality. CONCLUSIONS: Outside ICU setting, CPAP was used mainly for hypoxemic non-hypercapnic ARF, NPPV for hypercapnic ARF. In-hospital mortality was mainly associated to patients' basal status (DNI status, CCI) rather than the baseline degree of ARF.

Willow seedlings from photooxidized seeds accelerate cotyledon death and anticipate first leaf emergence: a histological and biochemical study following germination.

In willow seeds, photooxidative damage is mainly restricted to the outer cotyledonary tissues, significantly reducing normal germination. Here we analyzed the damage generated in cotyledonary tissues and investigated whether the increase in reactive oxygen species (ROS) generation in seedlings from photooxidized seeds can affect the morphogenetic capacity of the shoot apical meristem. Seeds were photooxidized under different light intensities and the evolution of the damage during seedling growth was studied by light and transmission electron microscopies. The level of lipid peroxidation and changes in antioxidant capacity were measured following the time course of superoxide dismutase, catalase, ascorbate peroxidase and guaiacol peroxidase enzyme activities, and the effect of photooxidative stress on the genesis of new leaf primordia and lateral roots was examined. Early and active endocytosis and autophagy, changes in chloroplast morphology, as well as the accumulation and diffusion of ROS all play important roles in the early cell death observed in cotyledonary tissues. Following germination, seedlings from photooxidized seeds anticipated the emergence of first leaves, which complemented the altered functionality of the damaged cotyledons.

Partitioning of soil water among tree species in a Brazilian Cerrado ecosystem.

Source water used by woody perennials in a Brazilian savanna (Cerrado) was determined by comparing the stable hydrogen isotope composition (deltaD) of xylem sap and soil water at different depths during two consecutive dry seasons (1995 and 1996). Plant water status and rates of water use were also determined and compared with xylem water deltaD values. Overall, soil water deltaD decreased with increasing depth in the soil profile. Mean deltaD values were -35 per thousand for the upper 170 cm of soil and -55 per thousand between 230 and 400 cm depth at the end of the 1995 dry season. Soil water content increased with depth, from 18% near the surface to about 28% at 400 cm. A similar pattern of decreasing soil water deltaD with increasing depth was observed at the end of the 1996 dry season. Patterns consistent with hydraulic lift were observed in soil profiles sampled in 1995 and 1997. Concurrent analyses of xylem and soil water deltaD values indicated a distinct partitioning of water resources among 10 representative woody species (five deciduous and five evergreen). Among these species, four evergreen and one deciduous species acquired water primarily in the upper soil layers (above 200 cm), whereas three deciduous and one evergreen species tapped deep sources of soil water (below 200 cm). One deciduous species exhibited intermediate behavior. Total daily sap flow was negatively correlated with xylem sap deltaD values indicating that species with higher rates of water use during the dry season tended to rely on deeper soil water sources. Among evergreen species, minimum leaf water potentials were also negatively correlated with xylem water deltaD values, suggesting that access to more readily available water at greater depth permitted maintenance of a more favorable plant water status. No significant relationship between xylem water deltaD and plant size was observed in two evergreen species, suggesting a strong selective pressure for small plants to rapidly develop a deep root system. The degree of variation in soil water partitioning, leaf phenology and leaf longevity was consistent with the high diversity of woody species in the Cerrado.