Urinary Oxalate Excretion and Long-Term Outcomes in Kidney Transplant Recipients

Epidemiologic studies have linked urinary oxalate excretion to risk of chronic kidney disease (CKD) progression and end-stage renal disease. We aimed to investigate whether urinary oxalate, in stable kidney transplant recipients (KTR), is prospectively associated with risk of graft failure. In secondary analyses we evaluated the association with post-transplantation diabetes mellitus, all-cause mortality and specific causes of death. Oxalate excretion was measured in 24-h urine collection samples in a cohort of 683 KTR with a functioning allograft >= 1 year. Mean eGFR was 52 +/- 20 mL/min/1.73 m(2). Median (interquartile range) urinary oxalate excretion was 505 (347-732) mu mol/24-h in women and 519 (396-736) mu mol/24-h in men (p = 0.08), with 302 patients (44% of the study population) above normal limits (hyperoxaluria). A consistent and independent inverse association was found with all-cause mortality (HR 0.77, 95% CI 0.63-0.94, p = 0.01). Cause-specific survival analyses showed that this association was mainly driven by an inverse association with mortality due to infection (HR 0.56, 95% CI 0.38-0.83, p = 0.004), which remained materially unchanged after performing sensitivity analyses. Twenty-four-hour urinary oxalate excretion did not associate with risk of graft failure, post-transplant diabetes mellitus, cardiovascular mortality, mortality due to malignancies or mortality due to miscellaneous causes. In conclusion, in KTR, 24-h urinary oxalate excretion is elevated in 44% of KTR and inversely associated with mortality due to infectious causes

Ruthenium promotion of platinum for the electrocatalytic oxidation of methanol

+178hlm.;24c

Long term monitoring of reactive gases and water soluble aerosol components at a remote field site in the UK

Long term deposition of inorganic reactive gases, such as NH3, HNO3, HCl, SO2 and their aerosol counter parts (NH4+, NO3-, Cl- and SO42-) have been demonstrated to contribute to the eutrophication and acidification of sensitive ecosystems. In addition, inorganic aerosols represent a significant proportion of tropospheric aerosols that have an important impact on human health and the climate system. Currently, PM2.5 and PM10 aerosols are mainly monitored by bulk mass methods. This however gives very little information on the contribution of different aerosol compounds to the total mass and on aerosol sources. In addition, composition data is needed to refine the epidemiological understanding of the aerosol metrics most closely associated with human health impacts. Long term real time measurements of chemically speciated inorganic aerosols and their precursor gases are needed to understand the sources of emissions, and aerosol processes in the atmosphere in order to implement effective emission reduction measures. Furthermore, long-term data sets are necessary to validate national and international chemical transport models, which are used to inform policy. The MARGA (Monitoring instrument for AeRosols and reactive Gases, Applikon Analytical BV, Netherlands) is an instrument that provides long term real time (hourly) measurements of water soluble inorganic aerosols (NH4+, NO3-, SO42-, Cl-) and their gas precursor (NH3, HNO3, HNO2, SO2, HCl). The MARGA is based on a wet chemistry method that utilises rotating annular wet denuders for the capture of reactive trace gases and steam jet aerosol collectors (SJACs) for the collection of soluble aerosols. Analysis is performed by online ion chromatography, providing hourly concentration values. Since June 2006 a MARGA has been operated continuously at the northern UK EMEP supersite ‘Auchencorth Moss’, monitoring the composition of both PM10 and PM2.5 aerosol. The work presented will focus on the MARGA method and the results of long term monitoring