Aim To investigate the impact of hypoglycaemia, hyperglycaemia and glycaemic variability on arrhythmia susceptibility in people with type 1 diabetes.Materials and Methods Thirty adults with type 1 diabetes were included in a 12-month observational exploratory study. Daytime and night-time incident rate ratios (IRRs) of arrhythmias were determined for hypoglycaemia (interstitial glucose [IG] <3.9 mmol/L), hyperglycaemia (IG >10.0 mmol/L) and glycaemic variability (standard deviation and coefficient of variation).Results Hypoglycaemia was not associated with an increased risk of arrhythmias compared with euglycaemia and hyperglycaemia combined (IG >= 3.9 mmol/L). However, during daytime, a trend of increased risk of arrhythmias was observed when comparing time spent in hypoglycaemia with euglycaemia (IRR 1.08 [95% CI: 0.99-1.18] per 5 minutes). Furthermore, during daytime, both the occurrence and time spent in hyperglycaemia were associated with an increased risk of arrhythmias compared with euglycaemia (IRR 2.03 [95% CI: 1.21-3.40] and IRR 1.07 [95% CI: 1.02-1.13] per 5 minutes, respectively). Night-time hypoglycaemia and hyperglycaemia were not associated with the risk of arrhythmias. Increased glycaemic variability was not associated with an increased risk of arrhythmias during daytime, whereas a reduced risk was observed during night-time.Conclusions Acute hypoglycaemia and hyperglycaemia during daytime may increase the risk of arrhythmias in individuals with type 1 diabetes. However, no such associations were found during night-time, indicating diurnal differences in arrhythmia susceptibility.

Recombinant human erythropoietin (rHuEPO) is ergogenic but micro-doses remain a challenge for anti-doping authorities. Here, we investigated the hypothesis that frequent micro-doses of rHuEPO enhance maximal oxygen consumption (VO2max) and time trial performance and that the combination of immature reticulocyte fraction (IRF) and the Athlete's Biological Passport (ABP) would enhance detection compared to the ABP alone. In a randomized, double-blinded, placebo-controlled design, 34 trained (VO2max: 52 ± 7 ml×min-1×kg-1, mean ± SD) adults received either rHuEPO (rHuEPO: epoetin-β, 9 IU/kg, n = 16) or placebo (PLA: 0.9% NaCl, n = 18) three times a week for four weeks. Before and after the intervention, VO2max, mean power output during a 400-kcal time trial and total hemoglobin mass (tHb) were measured. Venous blood samples were collected before, each week during rHuEPO administration, and 3, 5 and 10 days after the last injection. Hematological values were evaluated using dedicated ABP software. VO2max increased by 4.7% (p<0.01) and tHb increased by 6.8% (p<0.001) in the rHuEPO group when compared to the PLA group where no changes were evident. Mean power output during the time trial increased by 4.0% (p<0.01) in the rHuEPO group with no changes observed in the PLA group. Inclusion of IRF thresholds improved ABP sensitivity from 47% to 73%, yielding a peak sensitivity during the first two weeks of the rHuEPO treatment and 10 days after cessation of treatment. In conclusion, these findings show that four weeks of rHuEPO micro-doses are sufficient to induce considerable ergogenic effects on both VO2max and time trial performance in trained adults. The inclusion of IRF thresholds into the ABP improved sensitivity during treatment and the viability of including IRF into the ABP should be considered although more studies are needed.

Ligation-independent cloning (LIC) allows for cloning of DNA constructs independent of insert restriction sites and ligases. However, any required mutations are typically introduced by additional, time-consuming steps. We present a rapid, inexpensive method for mutagenesis in the 5' LIC site of expression constructs and report on the construction of expression vectors with N-terminal serine, cysteine, threonine, or tyrosine residues after tobacco etch virus (TEV) protease cleavage. In a practical application, the N-terminal serine was oxidized to an aldehyde, subsequently reacted with an amino-oxy functionalized polyethylene glycol (PEG) ligand under aniline catalysis to provide a protein selectively modified at the N-terminus.