Background: Microalbuminuria is an early sign of kidney disease in diabetes and indicates cardiovascular risk. We tested if a prespecified urinary proteomic risk classifier (CKD273) was associated with development of microalbuminuria and if progression to microalbuminuria could be prevented with the mineralocorticoid receptor antagonist spironolactone. Methods: Prospective multicentre study in people with type 2 diabetes, normal urinary albumin excretion and preserved renal function in 15 European specialist centres. High-risk individuals determined by CKD273 were randomised 1:1 (interactive web response system) in a double-blind randomised controlled trial comparing spironolactone 25 mg o.d. to placebo. Primary endpoint was development of confirmed microalbuminuria in all individuals with available data. Secondary endpoints included reduction in incidence of microalbuminuria with spironolactone and association between CKD273 and impaired renal function defined as a glomerular filtration rate < 60 ml/min per 1•73 m 2. This study is registered with ClinicalTrials.gov: NCT02040441 and is completed. Findings: From March 25, 2014 to September 30, 2018 we followed 1775 participants, 12% (n=216) had high-risk urinary proteomic pattern of which 209 were included in the trial and assigned spironolactone (n=102) or placebo (n=107). Median follow-up time was 2•51 years (IQR 2•0-3•0). Progression to microalbuminuria was seen in 28•2% of high-risk and 8•9% of low-risk people (P< 0•001) (hazard ratio (HR), 2•48; 95% confidence interval [CI], 1•80 to 3•42 P<0•001, independent of baseline clinical characteristics). A 30% decline in eGFR from baseline was seen in 42 (19•4 %) high-risk participants compared to 62 (3•9 %) low-risk participants, HR 5•15; 95 % CI (3•41 to 7•76; p<0.0001). Development of microalbuminuria was seen in 35 (33%) randomised to placebo and 26 (25%) randomised to spironolactone treatment (HR 0•81, 95% CI, 0•49 to 1•34, P=0•41). Harms: hyperkalaemia was seen in 13 versus 4, and gynaecomastia in 3 versus 0 subjects on spironolactone and placebo, respectively. Interpretation: In people with type 2 diabetes and normoalbuminuria, the urinary proteomic classifier CKD273 was associated with a 2•5 times increased risk for progression to microalbuminuria over a median of 2•5 years, independent of clinical characteristics. Spironolactone did not prevent progression to microalbuminuria in high-risk subjects.

Polybenzimidazoles are promising materials to replace Nafion™ as the electrolyte in HT-PEMFCs. One of their problems is striking the proper balance between the H 3 PO 4 doping level, which controls the proton conductivity, and the long-term stability properties of the membrane. Monomer modification is a promising way to maintain high conductivity levels with reduced doping. Here, we reported a novel and facile approach to obtaining an easy modular and reproducible sulfonation degree. Some aryloxy-based polybenzimidazoles were synthesized and sulfonated with different amounts of -SO 3 H. We prepared many electrolyte membranes by doping the pristine polymers in solutions with different H 3 PO 4 concentrations. The sulfonation degree greatly affected both acid uptake and conductivity. In particular, the membranes holding more protogenic groups absorbed less acid than the monosulfonated ones.However, polysulfonation was particularly efficient in improving proton conductivity at low relative humidity and doping level. We performed MEAs tests at 150 C using H 2 and air as the reactant gases, without any external humidification. We obtained power densities higher than 320 mW cm À2 , with fuel cell performances of approximately 580 mV at 0.2 A cm À2 , independent of the number of sulfonic groups. Preliminary durability tests did not show any membrane degradation over a 190 hour period. The reported membranes are therefore suitable for use in HT-PEMFCs.

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Polybenzimidazoles (PBIs) are promising materials to replace Nafion as the electrolyte in polymer electrolyte membrane fuel cells (PEMFCs). The challenge with these materials is to achieve a good compromise between the H3PO4 doping level and membrane stability. This can be obtained by a proper monomer design, which can lead to better performing membrane electrode assemblies (MEAs), in terms of durability, acid leaching, and electrode safety. Here the easy and inexpensive synthesis of hexafluoropropylidene oxyPBI (F6‐oxyPBI) and bisulfonated hexafluoropropylidene oxyPBI (F6‐oxyPBI‐2SO3H) is reported. The membranes based on F6‐oxyPBI‐2SO3H are more stable in an oxidative environment and more mechanically resistant than standard PBI and F6‐oxyPBI. Whereas the attainable doping levels are low because of fluorine‐induced hydrophobicity, polysulfonation allows high proton conductivity, and fuel cell performances better than those reported for MEAs with F6PBI‐ or PBI membranes with much higher doping levels. In the case of MEA with a F6‐oxyPBI‐2SO3H membrane, a peak power density of 360 mW cm−2 is measured. Fuel cell performances of 604 mV at 0.2 A cm−2 are maintained for 800 h without membrane degradation. Low H2 permeability is measured, which remains almost unaffected during a 1000 h life‐test.

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