Michael T. Lund

Quantitative vertebral morphometry using neighbor-conditional shape models

A novel method for vertebral fracture quantification from X-ray images is presented. Using pairwise conditional shape models trained on a set of healthy spines, the most likely normal vertebra shapes are estimated conditional on all other vertebrae in the image. The differences between the true shape and the reconstructed normal shape is subsequently used as a measure of abnormality. In contrast with the current (semi-)quantitative grading strategies this method takes the full shape into account, it uses a patient-specific reference by combining population-based information on biological variation in vertebra shape and vertebra interrelations, and it provides a continuous measure of deformity. The method is demonstrated on 212 lateral spine radiographs with in total 78 fractures. The distance between prediction and true shape is 1.0 mm for unfractured vertebrae and 3.7 mm for fractures, which makes it possible to diagnose and assess the severity of a fracture.

Preoperative β‐cell function in patients with type 2 diabetes is important for the outcome of Roux‐en‐Y gastric bypass surgery

Roux‐en‐Y gastric bypass surgery leads to remission of type 2 diabetes in the majority of patients suffering from the disease. The gut hormone glucagon‐like peptide‐1 is believed to be of major importance for the remission process. The present project demonstrates a marked difference in the chance of remission of type 2 diabetes in patients with low or high preoperative β‐cell function in spite of a similar post‐surgery increase in postprandial glucagon‐like peptide‐1 release. Furthermore, post‐surgery intravenous glucose administration, which does not stimulate release of glucagon‐like peptide‐1, leads to increased insulin secretion in the patients with the best preoperative β‐cell function. Together the present findings indicate that patients with type 2 diabetes with high preoperative β‐cell function experience a glucagon‐like peptide‐1‐independent increase in β‐cell function after gastric bypass surgery.

Adipose tissue mitochondrial respiration and lipolysis before and after a weight loss by diet and RYGB.

To study adipose tissue mitochondrial respiration and lipolysis following a massive weight loss.

Immobilization increases interleukin‐6, but not tumour necrosis factor‐α, release from the leg during exercise in humans

•  What is the central question of this study? Does physical inactivity influence the exercise‐induced release of tumour necrosis factor‐α and interleukin‐6 in healthy humans? In young, healthy subjects, we immobilized one leg for 2 weeks, followed by 45 min two‐legged exercise where one leg served as the control and the other was the previously inactive leg. •  What is the main finding and its importance? We found that prior physical inactivity enhances interleukin‐6 release during exercise, and it is released in the blood from the legs during exercise much faster than previously known. However, tumour necrosis factor‐α is not released in the blood with exercise, even from a previously inactive leg.

Hepatic mitochondrial oxidative phosphorylation is normal in obese patients with and without type 2 diabetes

Hepatic insulin resistance in patients with obesity or type 2 diabetes has been suggested to result from hepatic mitochondrial dysfunction. High‐resolution respirometry (HRR) can be used to assess oxidative phosphorylation by measuring the mitochondrial oxygen consumption rate in the individual complexes of the mitochondria. By using HRR, the present study demonstrates no difference in hepatic mitochondrial oxidative phosphorylation among subjects with obesity with or without type 2 diabetes and non‐obese controls. Furthermore, the amount of mitochondria, assessed by the citrate synthase activity, is not different between the three groups. Together the present findings indicate that hepatic mitochondrial oxidative phosphorylation capacity is not impaired in patients with obesity or type 2 diabetes.

A novel method for determining human ex vivo submaximal skeletal muscle mitochondrial function.

The present study utilized a novel method aiming to investigate mitochondrial function in human skeletal muscle at submaximal levels and at a predefined membrane potential. The effect of age and training status was investigated using a cross‐sectional design. Ageing was found to be related to decreased leak regardless of training status. Increased training status was associated with increased mitochondrial hydrogen peroxide emission.

The Effect of Preoperative Type 2 Diabetes and Physical Fitness on Mental Health and Health-Related Quality of Life after Roux-en-Y Gastric Bypass.

Objective. To investigate the predictive value of type 2 diabetes and lack of physical activity for mental health and health-related quality of life after Roux-en-Y gastric bypass. Method. Forty severely obese patients undergoing Roux-en-Y gastric bypass were included in the GASMITO study. Information about physiological and psychological factors was prospectively assessed at four time points, two times prior to surgery and two times after surgery. Measures included oral and intravenous glucose tolerance tests, VO2max test, Symptoms Checklist (SCL-90), Short Form Health Survey 36 (SF-36), Body Image Questionnaire, and a questionnaire assessing sociodemographic factors and medical status. Results. Mean % excess weight loss was 65% (±12) at 18-month follow-up and 50% of the participants with diabetes experienced total remission. Also, significant improvements were observed with regard to physical fitness, mental distress, health-related quality of life, and weight-related body image (p < 0.05). The interaction between follow-up time and type 2 diabetes at baseline significantly predicted six of the thirteen psychological subscales (p < 0.05) and, across the follow-ups, physical fitness level made modest contributions to variations in mental symptoms and HRQOL but not weight-related body image. Conclusion. The results suggest that baseline difference in mental symptoms and physical HRQOL between diabetic and nondiabetic patients declines across follow-ups and resolves around the time of surgery.

Macrophage Area Content and Phenotype in Hepatic and Adipose Tissue in Patients with Obesity Undergoing Roux-en-Y Gastric Bypass

To investigate hepatic and adipose tissue macrophage content in subjects with obesity and the role of adipose tissue macrophages in weight loss‐induced improved insulin sensitivity (IS).