Social inequality in lifestyle, motivation to change lifestyle and received health advice in individuals with diabetes: A nationwide study.

Aims: The aim was to investigate the association between socioeconomic position (SEP) and physical activity, alcohol consumption and smoking, motivation to change lifestyle and health advices from general practitioners (GPs) in individuals with diabetes. Methods: Data were provided by the Danish National Health Survey 2013 and 7504 adults (⩾ 40 years) with diabetes were included. Educational level was used as SEP indicator and categorized into low, middle and high SEP. Dependent variables included physical activity, alcohol consumption, smoking, motivation to change lifestyle and GP lifestyle advices. Multiple logistic regression analyses adjusted for age, body mass index and ethnic background were performed. Results: Higher SEP were associated with reduced odds of being physically inactive (middle SEP odds ratio (OR) men 0.58 (95% confidence intervals 0.47-0.72) and women 0.59 (0.47-0.75)) and non-smoking (middle SEP OR men 0.74 (0.59-0.93) and high SEP OR women 0.54 (0.38-0.77)) compared to participants with a low SEP. Alcohol consumption above the recommended maximum was associated with high SEP in men, OR 1.83 (1.30-2.61). Elevated SEP was associated with a motivation to increase physical activity levels (middle SEP OR men 1.45 (1.19-1.76) and women 1.35 (1.09-1.67)), high SEP was associated with none advice from GPs regarding smoking cessation among women, OR 0.47 (0.25-0.89). Conclusions: Socioeconomic position was strongly associated with lifestyle in individuals with diabetes. The most pronounced inequalities were found in physical activity levels, smoking status and the motivation to become more physically active. Municipalities and GPs may need a greater focus on SEP in interventions to change lifestyle in individuals with diabetes.

Crystal structure of tetrameric human Rabin8 GEF domain.

Rab GTPases and their effectors, activators and guanine nucleotide exchange factors (GEFs) are essential for vesicular transport. Rab8 and its GEF Rabin8 function in formation of the cilium organelle important for developmental signaling and sensory reception. Here, we show by size exclusion chromatography and analytical ultracentrifugation that Rabin8 exists in equilibrium between dimers and tetramers. The crystal structure of tetrameric Rabin8 GEF domain reveals an occluded Rab8 binding site suggesting that this oligomer is enzymatically inactive, a notion we verify experimentally using Rabin8/Rab8 GEF assays. We outline a procedure for the purification of active dimeric Rabin8 GEF-domain for in vitro activity assays.

Purification and crystal structure of human ODA16: Implications for ciliary import of outer dynein arms by the intraflagellar transport machinery.

Motile cilia protrude from cell surfaces and are necessary to create movement of cells and fluids in the body. At the molecular level, cilia contain several dynein molecular motor complexes including outer dynein arms (ODAs) that are attached periodically to the ciliary axoneme, where they hydrolyse ATP to create the force required for bending and motility of the cilium. ODAs are preassembled in the cytoplasm and subsequently trafficked into the cilium by the intraflagellar transport (IFT) system. In the case of the green alga Chlamydomonas reinhardtii, the adaptor protein ODA16 binds to ODAs and directly to the IFT complex component IFT46 to facilitate the ciliary import of ODAs. Here, we purified recombinant human IFT46 and ODA16, determined the high-resolution crystal structure of the ODA16 protein, and carried out direct interaction studies of IFT46 and ODA16. The human ODA16 C-terminal 320 residues adopt the fold of an eight-bladed ß-propeller with high overall structural similarity to the Chlamydomonas ODA16. However, the small 80 residue N-terminal domain, which in Chlamydomonas ODA16 is located on top of the ß-propeller and is required to form the binding cleft for IFT46, has no visible electron density in case of the human ODA16 structure. Furthermore, size exclusion chromatography and pull-down experiments failed to detect a direct interaction between human ODA16 and IFT46. These data suggest that additional factors may be required for the ciliary import of ODAs in human cells with motile cilia.

Advantages of an optical nanosensor system for the mechanistic analysis of a novel topoisomerase I targeting drug: a case study.

The continuous need for the development of new small molecule anti-cancer drugs calls for easily accessible sensor systems for measuring the effect of vast numbers of new drugs on their potential cellular targets. Here we demonstrate the use of an optical DNA biosensor to unravel the inhibitory mechanism of a member of a new family of small molecule human topoisomerase I inhibitors, the so-called indeno-1,5-naphthyridines. By analysing human topoisomerase I catalysis on the biosensor in the absence or presence of added drug complemented with a few traditional assays, we demonstrate that the investigated member of the indeno-1,5-naphthyridine family inhibited human topoisomerase I activity by blocking enzyme-DNA dissociation. To our knowledge, this represents the first characterized example of a small molecule drug that inhibits a post-ligation step of catalysis. The elucidation of a completely new and rather surprising drug mechanism-of-action using an optical real time sensor highlights the value of this assay system in the search for new topoisomerase I targeting small molecule drugs.