| 1. |
- Engström, Björn E., et al.
(author)
-
Meal suppression of circulating ghrelin is normalized in obese individuals following gastric bypass surgery
- 2007
-
In: International Journal of Obesity. - : Springer Science and Business Media LLC. - 0307-0565 .- 1476-5497. ; 31:3, s. 476-480
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: It has been proposed that the success of maintained weight loss in morbidly obese subjects following Roux-en-Y gastric bypass (RYGBP) surgery depends on inappropriately low circulating concentrations of the appetite-stimulating peptide ghrelin, being unresponsive to food intake. In this study, this hypothesis was examined. DESIGN: Cross-sectional study with repeated blood samples in 40 subjects after 14 h of prolonged overnight fasting followed by a standardized mixed meal (770 kcal). SUBJECTS: Twenty men and 20 women were included: 10 middle-aged morbidly obese (body mass index (BMI) 43.9+/-3.3 kg/m(2)), 10 middle-aged subjects who had undergone RYGBP at the Uppsala University Hospital (BMI 34.7+/-5.8 kg/m(2)), 10 middle-aged non-obese (BMI 23.5+/-2.2 kg/m(2)) and 10 young non-obese (BMI 22.7+/-1.8 kg/m(2)). MEASUREMENTS: Ghrelin, glucose and insulin levels were analysed pre- and postprandially. RESULTS: In the morbidly obese, ghrelin concentrations were lower in the morning than in the RYGBP group and did not change following the meal. In the RYGBP group, fasting ghrelin levels fell after meal intake and showed similar suppression as both age-matched and young non-obese controls. The RYGBP surgery resulted in an increased meal-induced insulin secretion, which was related to the degree of postprandial ghrelin suppression. CONCLUSION: The present study demonstrates low circulating concentrations of ghrelin and blunted responses to fast and feeding in morbidly obese subjects. Marked weight reduction after RYGBP at our hospital is followed by a normalization of ghrelin secretion, illustrated by increased fasting levels compared to the preoperative obese state and regain of meal-induced ghrelin suppression.
|
|
| 2. |
|
|
| 3. |
- Holdstock, Camilla, et al.
(author)
-
CRP reduction following gastric bypass surgery is most pronounced in insulin-sensitive subjects
- 2005
-
In: International Journal of Obesity. - : Springer Science and Business Media LLC. - 0307-0565 .- 1476-5497. ; 29:10, s. 1275-1280
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: Obesity is frequently associated with insulin resistance, dyslipidemia, hypertension and an increased risk ofcardiovascular disease, reflected in elevated markers of inflammation, in particular C-reactive protein (CRP). To what extent theinsulin resistance or the obesity per se contributes to increased CRP levels is unclear. In morbidly obese patients, gastric bypasssurgery causes marked changes in body weight and improves metabolism, thereby providing informative material for studies onthe regulation of inflammatory markers.DESIGN: Prospective, surgical intervention study of inflammatory markers in morbidly obese subjects.SUBJECTS: In total, 66 obese subjects with mean age 39 y and mean body mass index (BMI) 45 kg/m2 were studied prior to and6 and 12 months following Roux-en-Y gastric bypass (RYGBP) surgery.MEASUREMENTS: Serum concentrations of high sensitivity CRP, serum amyloid A (SAA) and interleukin-6 (IL-6), as well asmarkers of glucose and lipid metabolism.RESULTS: Prior to surgery, CRP levels were elevated compared to the reference range of healthy, normal-weight subjects. CRPcorrelated with insulin sensitivity, as reflected by the homeostatic model assessment (HOMA) index, but not BMI, whencorrected for age and gender. Surgery reduced BMI from 45 to 31 kg/m2 and lowered CRP, SAA and IL-6 levels by 82, 57 and50%, respectively, at 12 months. The reduction in CRP was inversely related to HOMA at baseline independently of the changein body weight (r=-0.36, P=0.005). At 12 months, 140 and 40% reductions in CRP were seen in subjects with HOMA o 4(insulin sensitive) and HOMA49 (insulin resistant) despite similar reductions in BMI. Reductions in SAA and IL-6 tended toparallel the changes in CRP, but were less informative.CONCLUSION: In morbidly obese subjects, gastric bypass surgery lowers energy intake, reduces inflammatory markers andimproves insulin sensitivity. Despite a marked reduction in body weight, only a small effect on CRP levels was seen in insulinresistantpatients, indicating that flexibility of circulating CRP levels is primarily dependent upon insulin sensitivity rather thanenergy supply.
|
|
| 4. |
|
|
| 5. |
- Lind, Lars, et al.
(author)
-
Vasoreactivity is rapidly improved in obese subjects after gastric bypass surgery
- 2009
-
In: International Journal of Obesity. - : Springer Science and Business Media LLC. - 0307-0565 .- 1476-5497. ; 33:12, s. 1390-5
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Obesity is associated with increased risk of cardiovascular disease. We investigated vasoreactivity in conduit and resistance arteries in morbidly obese subjects, and the effect of weight loss after gastric bypass surgery. METHODS: A total of 19 obese subjects (body mass index (BMI): 43.8+/-3.1 kg m(-2), 75% female, mean age 41 years) were investigated before surgery and after 1 and 12 months of surgery. Nineteen non-obese controls matched for age and gender were examined. Vasoreactivity was evaluated by ultrasound to measure flow-mediated dilation (FMD, evaluating a conduit vessel) and pulse-wave analysis with terbutaline provocation (change in reflectance index (RI), evaluating resistance vessels). RESULTS: Before surgery, the obese showed a low change in RI (18+/-12 vs 37+/-15% in controls, P=0.0001), but not significantly regarding FMD (7.9+/-6.4 vs 8.9+/-5.4% in controls). Surgery resulted in a weight loss of 9% at 1 month and 30% at 1 year. Change in RI markedly improved to 36+/-12% at 1 month (P=0.0001 vs baseline) and further to 44+/-11% at 1 year (P=0.014 vs 1 month). FMD did not change significantly. Heart rate and brachial artery diameter were reduced, with no significant change in blood pressure. The improvement in resistance vessel vasodilation, estimated as change in RI, was not correlated to changes in weight or measures of glucose and lipid metabolism. CONCLUSIONS: Obese patients showed impaired vasoreactivity in resistance arteries that was normalized already 1 month after gastric bypass surgery. The basis for this remarkable outcome, not significantly related to changes in body weight and metabolic variables, remains to be clarified.
|
|
| 6. |
- Strand, Robin, 1978-, et al.
(author)
-
A concept for holistic whole body MRI data analysis, Imiomics
- 2017
-
In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 12:2
-
Journal article (peer-reviewed)abstract
- Purpose: To present and evaluate a whole-body image analysis concept, Imiomics (imaging omics) and an image registration method that enables Imiomics analyses by deforming all image data to a common coordinate system, so that the information in each voxel can be compared between persons or within a person over time and integrated with non-imaging data.Methods: The presented image registration method utilizes relative elasticity constraints of different tissue obtained from whole-body water-fat MRI. The registration method is evaluated by inverse consistency and Dice coefficients and the Imiomics concept is evaluated by example analyses of importance for metabolic research using non-imaging parameters where we know what to expect. The example analyses include whole body imaging atlas creation, anomaly detection, and cross-sectional and longitudinal analysis.Results: The image registration method evaluation on 128 subjects shows low inverse consistency errors and high Dice coefficients. Also, the statistical atlas with fat content intensity values shows low standard deviation values, indicating successful deformations to the common coordinate system. The example analyses show expected associations and correlations which agree with explicit measurements, and thereby illustrate the usefulness of the proposed Imiomics concept.Conclusions: The registration method is well-suited for Imiomics analyses, which enable analyses of relationships to non-imaging data, e.g. clinical data, in new types of holistic targeted and untargeted big-data analysis.
|
|
| 7. |
- Strand, Robin, 1978-, et al.
(author)
-
Holistic whole-body MRI image analysis
- 2016
-
In: Symposium of the Swedish Society for Automated Image Analysis, Uppsala, Sweden, (SSBA).
-
Conference paper (other academic/artistic)
|
|
