Metabolic Surgery Supporting Aftercare via Group-Intervention (MeSSAGES): study protocol of a randomised controlled trial.

INTRODUCTION: Obesity is a constantly rising and cost-intensive medical issue worldwide. Severe obesity often needs surgery to promote weight loss, but due to the rapid therapeutic success after the surgery, many patients lack the awareness of the need to consistently maintain the postoperative care. However, therapeutic success and psychological well-being can be increased through group interventions and social support of the group members. Therefore, aftercare via group intervention is a promising approach. In this prospective randomised controlled study, the self-efficacy in a social media-based interactive, psychoeducational intervention is to be tested. METHODS AND ANALYSIS: The intervention group will complete a social media-supported group intervention for 6 weeks with weekly postings of educative contents and the possibility to exchange in groups via anonymous avatars. The control group will receive treatment as usual (TAU) after the obesity surgery as recommended in the German S3-guidelines Obesity Surgery and Metabolic Surgery. We will examine the effectiveness of a social media-supported intervention group, and therefore, the change in self-efficacy expectation. For the primary outcome, we will perform a mixed analysis of variance with time as the within-subject factor (times of measurement T0-T4) and the group assignment as the between-subject factor (intervention +TAU vs TAU group). ETHICS AND DISSEMINATION: The study was approved by the Medical Association North Rhine (Ärztekammer Nordrhein, 2020031) and the patient enrolment will begin in July 2021. TRIAL REGISTRATION NUMBER: DRKS00018089.

Identification of Patients with Pancreatic Cancer by Electron Paramagnetic Resonance Spectroscopy of Fatty Acid Binding to Human Serum Albumin.

An effective biological marker for pancreatic adenocarcinoma (PAC) is not available so far. Here, we investigate how electron paramagnetic resonance (EPR) spectroscopy of spin-labeled fatty acid (FA) molecules binding to human serum albumin (HSA) in human serum is a suitable method for the identification of patients with PAC through detection of PAC-induced changes of FA binding to albumin. The functionality of HSA to bind FA is investigated in serum samples of 35 patients with PAC, 26 patients with benign pancreatic tumors (BPD), and 24 healthy individuals by continuous wave (CW) EPR spectroscopy by simply dissolving 16-DOXYL stearic acid as spin-labeled FA. It is found that FA binding to HSA in PAC is significantly modified when compared with healthy and BPD individuals. The PAC group could best be discriminated from the healthy group based on EPR characteristics at the loading ratio of 1:4 (HSA:FA), while patients with PAC and BPD are distinguishable at a loading ratio of 1:6. Using nanoscale distance measurements through double electron-electron resonance (DEER), it is found that the distribution of FAs in the HSA of one PAC patient is similar to that of FAs in healthy individuals. Combining all EPR spectroscopic data, this leads to a tentative molecular interpretation of only small changes in hydration at the protein's surface as origin of the detectable characteristics for PAC patients. Thus, EPR of FA/HSA binding is a simple and promising tool for clinical detection of patients with PAC and needs to be tested with larger ensembles of different patient groups.

Fatty Acid Binding to Human Serum Albumin in Blood Serum Characterized by EPR Spectroscopy.

One of the functions of Human Serum Albumin (HSA) is binding and transport of fatty acids. This ability could be altered by the presence of several blood components such as toxins or peptides - which in turn alters the functionality of the protein. We aim at characterizing HSA and its fatty acid binding in native serum environment. Native ligand binding and deviations from normal function can be monitored by electron paramagnetic resonance (EPR) spectroscopy using spin labeled fatty acids (FAs). Blood serum from healthy individuals is used to examine healthy HSA in its natural physiological conditions at different loading ratios of protein to FAs. Among the EPR spectroscopic parameters (like hyperfine coupling, line shape, rotational correlation time and population of different binding sites) the rotational correlation time is found to differ significantly between binding sites of the protein, especially at loading ratios of four FAs per HSA. Although differences are observed between individual samples, a general trend regarding the dynamics of healthy HSA at different loading ratios could be obtained and compared to a reference of purified commercially available HSA in buffer.