Blood glucose and prognosis in children with presumed severe malaria: is there a threshold for 'hypoglycaemia'?

OBJECTIVES: Hypoglycaemia (glucose <2.2 mmol/l) is a defining feature of severe malaria, but the significance of other levels of blood glucose has not previously been studied in children with severe malaria. METHODS: A prospective study of 437 consecutive children with presumed severe malaria was conducted in Mali. We defined hypoglycaemia as <2.2 mmol/l, low glycaemia as 2.2-4.4 mmol/l and hyperglycaemia as >8.3 mmol/l. Associations between glycaemia and case fatality were analysed for 418 children using logistic regression models and a receiver operator curve (ROC). RESULTS: There was a significant difference between blood glucose levels in children who died (median 4.6 mmol/l) and survivors (median 7.6 mmol/l, P < 0.001). Case fatality declined from 61.5% of the hypoglycaemic children to 46.2% of those with low glycaemia, 13.4% of those with normal glycaemia and 7.6% of those with hyperglycaemia (P < 0.001). Logistic regression showed an adjusted odds ratio (AOR) of 0.75 (0.64-0.88) for case fatality per 1 mmol/l increase in baseline blood glucose. Compared to a normal blood glucose, hypoglycaemia and low glycaemia both significantly increased the odds of death (AOR 11.87, 2.10-67.00; and 5.21, 1.86-14.63, respectively), whereas hyperglycaemia reduced the odds of death (AOR 0.34, 0.13-0.91). The ROC [area under the curve at 0.753 (95% CI 0.684-0.820)] indicated that glycaemia had a moderate predictive value for death and identified an optimal threshold at glycaemia <6.1 mmol/l, (sensitivity 64.5% and specificity 75.1%). CONCLUSIONS: If there is a threshold of blood glucose which defines a worse prognosis, it is at a higher level than the current definition of 2.2 mmol/l.

Simulating Energy Transfer and Upconversion in β-NaYF 4 : Yb 3+ , Tm 3+

The design of upconversion phosphors with higher quantum yield requires a deeper understanding of the detailed energy transfer and upconversion processes between active ions inside the material. Rate equations can model those processes by describing the populations of the energy levels of the ions as a function of time. However, this model presents some drawbacks: energy migration is assumed to be infinitely fast, it does not determine the detailed interaction mechanism (multipolar or exchange), and it only provides the macroscopic averaged parameters of interaction. Hence, a rate equation model with the same parameters cannot correctly predict the time evolution of upconverted emission and power dependence under a wide range of concentrations of active ions. We present a model that combines information about the host material lattice, the concentration of active ions, and a microscopic rate equation system. The extent of energy migration is correctly taken into account because the energy transfer processes are described on the level of the individual ions. This model predicts the decay curves, concentration, and excitation power dependences of the emission. This detailed information can be used to predict the optimal concentration that results in the maximum upconverted emission.

First generation versus second generation drug-eluting stents for the treatment of bifurcations: 5-year follow-up of the LEADERS all-comers randomized trial.

BACKGROUND Historically, percutaneous coronary intervention (PCI) of bifurcation lesions was associated with worse procedural and clinical outcomes when compared with PCI of non-bifurcation lesions. Newer generation drug-eluting stents (DES) might improve long-term clinical outcomes after bifurcation PCI. METHODS AND RESULTS The LEADERS trial was a 10-center, assessor-blind, non-inferiority, all-comers trial, randomizing 1,707 patients to treatment with a biolimus A9(TM) -eluting stent (BES) with an abluminal biodegradable polymer or a sirolimus-eluting stent (SES) with a durable polymer (ClinicalTrials.gov Identifier: NCT00389220). Five-year clinical outcomes were compared between patients with and without bifurcation lesions and between BES and SES in the bifurcation lesion subgroup. There were 497 (29%) patients with at least 1 bifurcation lesion (BES = 258; SES = 239). At 5-year follow-up, the composite endpoint of cardiac death, myocardial infarction (MI) and clinically-indicated (CI) target vessel revascularization (TVR) was observed more frequently in the bifurcation group (26.6% vs. 22.4%, P = 0.049). Within the bifurcation lesion subgroup, no differences were observed in (cardiac) death or MI rates between BES and SES. However, CI target lesion revascularization (TLR) (10.1% vs. 15.9%, P = 0.0495), and CI TVR (12.0% vs. 19.2%, P = 0.023) rates were significantly lower in the BES group. Definite/probable stent thrombosis (ST) rate was numerically lower in the BES group (3.1% vs. 5.9%, P = 0.15). Very late (>1 year) definite/probable ST rates trended to be lower with BES (0.4% vs. 3.1%, P = 0.057). CONCLUSIONS In the treatment of bifurcation lesions, use of BES led to superior long-term efficacy compared with SES. Safety outcomes were comparable between BES and SES, with an observed trend toward a lower rate of very late definite/probable ST between 1 and 5 years with the BES. © 2015 Wiley Periodicals, Inc.