Determination of dialysis dose: a clinical comparison of methods.

BACKGROUND: Guidelines recommend regular measurements of the delivered hemodialysis dose Kt/V. Nowadays, automatic non-invasive online measurements are available as alternatives to the conventional method with blood sampling, laboratory analysis, and calculation. METHODS: In a prospective clinical trial, three different methods determining dialysis dose were simultaneously applied: Kt/V(Dau) (conventional method with Daugirdas' formula), Kt/V(OCM) [online clearance measurement (OCM) with urea distribution volume V based on anthropometric estimate], and Kt/V(BCM) [OCM measurement with V measured by bioimpedance analysis (Body Composition Monitor)]. RESULTS: 1,076 hemodialysis patients were analyzed. The dialysis dose was measured as Kt/V(Dau) = 1.74 ± 0.45, Kt/V(OCM) = 1.47 ± 0.34, and Kt/V(BCM) = 1.65 ± 0.42. The difference between Kt/V(OCM) and Kt/V(BCM) was due to the difference between anthropometric estimated V(Watson) and measured V(BCM). Compared to Kt/V(Dau), Kt/V(OCM) was 15% lower and Kt/V(BCM) 5% lower. Kt/V(Dau) was incidentally prone to falsely high values due to operative errors, whereas in these cases OCM-based measurements Kt/V(OCM) and Kt/V(BCM) delivered realistic values. CONCLUSIONS: The automated OCM Kt/V(OCM) with anthropometric estimation of urea distribution volume was the easiest method to use, but Kt/V(BCM) with measured urea distribution volume was closer to the conventional method.

Common ELIXIR Service for Researcher Authentication and Authorisation.

A common Authentication and Authorisation Infrastructure (AAI) that would allow single sign-on to services has been identified as a key enabler for European bioinformatics. ELIXIR AAI is an ELIXIR service portfolio for authenticating researchers to ELIXIR services and assisting these services on user privileges during research usage. It relieves the scientific service providers from managing the user identities and authorisation themselves, enables the researcher to have a single set of credentials to all ELIXIR services and supports meeting the requirements imposed by the data protection laws. ELIXIR AAI was launched in late 2016 and is part of the ELIXIR Compute platform portfolio. By the end of 2017 the number of users reached 1000, while the number of relying scientific services was 36. This paper presents the requirements and design of the ELIXIR AAI and the policies related to its use, and how it can be used for serving some example services, such as document management, social media, data discovery, human data access, cloud compute and training services.

Ghrelin variants influence development of body mass index and plasma levels of total cholesterol in dialyzed patients.

BACKGROUND: Ghrelin is an endogenous hormone expressed predominantly in the stomach. Ghrelin controls growth hormone secretion and also affects the body's energy balance. We analyzed the association of ghrelin variants with body mass index (BMI), albumin as a marker of malnutrition and plasma lipids as risk factors for atherosclerosis in hemodialyzed patients, in whom malnutrition and accelerated atherosclerosis are common complications. METHODS: Ghrelin variants Arg51>Gln and Leu72> Met were analyzed by PCR-RFLP in 210 hemodialyzed patients, prospectively followed up for 15 months. Changes in body mass index, triglycerides, total cholesterol and albumin over time (after 3, 6, 9, 12 and 15 months of dialysis) were analyzed in subgroups divided according to ghrelin genotypes. RESULTS: Carriers of at least one of the Gln51 and Met72 alleles lost body weight more quickly than Arg51Arg/Leu72Leu homozygotes (p<0.01). Carriers of the Gln51 allele were at higher risk of developing high cholesterol levels (p<0.01). CONCLUSIONS: Common ghrelin variants may have an effect on changes in biochemical and anthropometric parameters in hemodialyzed patients over time and could be used in the future to plan individualized therapy.