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The glucagon receptor (GCGR) is emerging as an important target in anti-diabetic therapy, especially as part of the pharmacology of dual glucagon-like peptide-1/glucagon (GLP-1/GCG) receptor agonists. However, currently, there are no suitable biomarkers that reliably demonstrate GCG receptor target engagement. Methods Two potent GCG receptor peptide agonists, S01-GCG and S02-GCG, were labeled with positron emission tomography (PET) radionuclide gallium-68. The GCG receptor binding affinity and specificity of the resulting radiopharmaceuticals [68Ga]Ga-DO3A-S01-GCG and [68Ga]Ga-DO3A-S02-GCG were evaluated in HEK-293 cells overexpressing the human GCG receptor and on frozen hepatic sections from human, non-human primate, and rat. In in vivo biodistribution, binding specificity and dosimetry were assessed in rat. Results [68Ga]Ga-DO3A-S01-GCG in particular demonstrated GCG receptor-mediated binding in cells and liver tissue with affinity in the nanomolar range required for imaging. [68Ga]Ga-DO3A-S01-GCG binding was not blocked by co-incubation of a GLP-1 agonist. In vivo binding in rat liver was GCG receptor specific with low non-specific binding throughout the body. Moreover, the extrapolated human effective doses, predicted from rat biodistribution data, allow for repeated PET imaging potentially also in combination with GLP-1R radiopharmaceuticals. Conclusion [68Ga]Ga-DO3A-S01-GCG thus constitutes a first-in-class PET tracer targeting the GCG receptor, with suitable properties for clinical development. This tool has potential to provide direct quantitative evidence of GCG receptor occupancy in humans. Electronic supplementary material The online version of this article (10.1186/s13550-019-0482-0) contains supplementary material, which is available to authorized users.

Ischemic myocardial contracture developed in a 21-year-old man following aortic and mitral valve replacement. The patient's circulation was supported totally for 6 days with an abdominal left ventricular assist device (ALVAD). Cardiac allografting was then undertaken. Samples of myocardium taken at the original operation and 6 days later at transplantation were analyzed ultrastructurally. At the onset of ischemic cortracture, left ventricular abnormalities included hypercontraction of myofibrils, loss of normal A-band and Z-band patterns, mitochondrial swelling with fusion of cristae, interfibrillar edema and glycogen depletion. Capillaries demonstrated swelling of endothelial cells and basement membrane disruption. Six days later, ultrastructural morphology showed further degeneration. The myofibrils remained hypercontracted, but were more fragmented. Degenerative changes in mitochondria were more advanced and calcium deposition in cristae was present. No glycogen was seen. The right ventricular myocardium exhibited significantly fewer ultrastructural abnormalities. The principal right ventricular changes were endothelial swelling and basement membrane disruption. Glycogen granules were present. Ischemic contracture affects the left ventricle more than the right, and the morphology becomes more abnormal with time. To our knowledge, this is the first instance wherein morphologic progressions of the ultrastructural alterations of ischemic contracture have been documented.

OBJECTIVE: The objective of this study was to highlight the relative preference of European gynecologic oncology trainees for workshops that could support and supplement their training needs.METHODS: A Web-based survey was sent to 900 trainees on the European Network of Young Gynaecological Oncologists database in November 2011. Respondents were asked to rate a 13-item questionnaire (using a 1- to 5-point Likert scale) on workshop topics they felt would most benefit their training requirements. Free text space for additional topics was also provided. Descriptive analysis was used to describe the mean scores reported for different items. A complete linkage hierarchical cluster analysis with Dendron plot was used to assess any clustering of data, and Cronbach α was used to assess the internal reliability of the questionnaire.RESULTS: One hundred ninety trainees from 37 countries responded to the survey, giving a 21% response rate. The 3 most important topics reported were laparoscopic surgery; surgical anatomy, and imaging techniques in gynecologic oncology. The Dendron plot indicated 4 different clusters of workshops (research related skills, supportive ancillary skills, related nonsurgical subspecialties, and core surgical skills) reflecting different competencies trainees need to meet. There was no significant association between individual country of training and workshop preference. The mean duration of the workshop preferred by 71% of respondents was 2 days. Cronbach α of the 13-item questionnaire was 0.78, which suggests good internal consistency/reliability.CONCLUSIONS: This report for the first time highlights the relative importance and significance European trainees attach to some of their training needs in gynecologic oncology. Laparoscopic surgery, surgical anatomy, and imaging appear to be the 3 areas of greatest need. The European Society of Gynaecological Oncology, other national specialist societies, and institutions should direct additional training efforts at these areas.