Laparoscopic gastric banding

Introduction: Laparoscopic gastric banding (LGB) is currently the most popular purely restrictive bariatric operation in Europe and many other countries. It has a low operative morbidity, but is associated with a substantial late complication rate. Many late complications have been attributed to technical errors or to the learning curve. The aim of this paper is to present our results with gastric banding after the learning curve in order to disclose the true incidence of long-term complications. Methods: LGB was introduced in our department in December 1995. Thirty patients were operated on until June 1997 using the early banding technique (band within the lesser sac), at which time the surgical technique was slightly modified in order to place the band above the lesser sac. Then another 300 patients underwent LGB using either the Lapband or the SAGB system. This report focuses on the latter patients. All the data were collected prospectively. Results: The series includes 300 patients (257 women and 43 men) with a mean age of 38.3 years (19-64). The mean initial weight was 119.2 kg (57-179), initial body mass index (BMI) was 43.3 kg/m2 (21-64), and initial excess weight was 96.5% (0-191). The mean duration of surgery was 90 min, decreasing over time to a mean of 75 min for the last 50 cases. Early overall morbidity was 6.6%. Major complications occurred in 7 patients (2.3%). Excess weight loss (EWL) was at least 50% in 66% of the patients after 2 years, averaging 60%, with no substantial change until 4 years, and the BMI stabilized between 30 and 31 kg/m2. Forty-nine patients developed a total of 52 long-term complications, of which 23 (7.6%) were related only to the port or catheter. Band erosion occurred in 17 (5.6%), pouch dilatation with slippage in 8 (2.6%), and infection in 4 (1.3%) patients. Fifty-five reoperations were necessary. Twenty-five of these were related only to the port. The band was removed from 26 (9%) patients, of whom 17 were converted to Roux-en-Y gastric bypass. Conclusions: LGB gives satisfactory results in terms of weight loss in about two-thirds of the patients. Even beyond the learning curve, the long-term morbidity is not negligible, but is acceptable compared to other procedures such as vertical banded gastroplasty. Conversion to gastric bypass is possible when complications occur and can be performed when the band is removed in most case

Compliance of the L5-S1 spinal unit: a comparative study between an unconstrained and a partially constrained system

A comparison between an unconstrained and a partially constrained system for in vitro biomechanical testing of the L5-S1 spinal unit was conducted. The objective was to compare the compliance and the coupling of the L5-S1 unit measured with an unconstrained and a partially constrained test for the three major physiological motions of the human spine. Very few studies have compared unconstrained and partially constrained testing systems using the same cadaveric functional spinal units (FSUs). Seven human L5-S1 units were therefore tested on both a pneumatic, unconstrained, and a servohydraulic, partially constrained system. Each FSU was tested along three motions: flexion-extension (FE), lateral bending (LB) and axial rotation (AR). The obtained kinematics on both systems is not equivalent, except for the FE case, where both motions are similar. The directions of coupled motions were similar for both tests, but their magnitudes were smaller in the partially constrained configuration. The use of a partially constrained system to characterize LB and AR of the lumbosacral FSU decreased significantly the measured stiffness of the segment. The unconstrained system is today's "gold standard” for the characterization of FSUs. The selected partially constrained method seems also to be an appropriate way to characterize FSUs for specific applications. Care should be taken using the latter method when the coupled motions are importan

Investigating the post-yield behavior of mineralized bone fibril arrays using a 3D non-linear finite element unit-cell model

Data availability: Data will be made available on request.Copyright © 2023 The Authors. In this study, we propose a 3D non-linear finite element (FE) unit-cell model to investigate the post-yield behavior of mineralized collagen fibril arrays (FAY). We then compare the predictions of the model with recent micro-tensile and micropillar compression tests in both axial and transverse directions. The unit cell consists of mineralized collagen fibrils (MCFs) embedded in an extrafibrillar matrix (EFM), and the FE mesh is equipped with cohesive interactions and a custom plasticity model. The simulation results confirm that MCF plays a dominant role in load bearing prior to yielding under axial tensile loading. Damage was initiated via debonding in shear and progressive sliding at the MCF/EFM interface, and resulted in MCF pull-out until brittle failure. In transverse tensile loading, EFM carried most of the load in pre-yield deformation, and then mixed normal/shear debonding between MCF and EFM began to form, which eventually produced brittle delamination of the two phases. The loading/unloading FE analysis in compression along both axial and transverse directions demonstrated perfect plasticity without any reduction in elastic modulus, i.e., damage due to the interfaces as seen in micropillar compression. Beyond the brittle and ductile nature of the stress–strain curves, in tensile and compressive loading, the simulated post-yield behavior and failure mechanism are in good quantitative agreement with the experimental observations. Our rather simple but efficient unit-cell FE model can reproduce qualitatively and quantitatively the mechanical behavior of bone ECM under tensile and compressive loading along the two main orientations. The model's integration into higher length scales may be useful in describing the macroscopic post-yield and failure behavior of trabecular and cortical bone in greater detail.Swiss Government Excellence Scholarship, Grant/Award Number (2021.0686)

The role of the gut microbiome in eye diseases.

The gut microbiome is a complex ecosystem of microorganisms and their genetic entities colonizing the gastrointestinal tract. When in balanced composition, the gut microbiome is in symbiotic interaction with its host and maintains intestinal homeostasis. It is involved in essential functions such as nutrient metabolism, inhibition of pathogens and regulation of immune function. Through translocation of microbes and their metabolites along the epithelial barrier, microbial dysbiosis induces systemic inflammation that may lead to tissue destruction and promote the onset of various diseases. Using whole-metagenome shotgun sequencing, several studies have shown that the composition and associated functional capacities of the gut microbiome are associated with age-related macular degeneration, retinal artery occlusion, central serous chorioretinopathy and uveitis. In this review, we provide an overview of the current knowledge about the gut microbiome in eye diseases, with a focus on interactions between the microbiome, specific microbial-derived metabolites and the immune system. We explain how these interactions may be involved in the pathogenesis of age-related macular degeneration, retinal artery occlusion, central serous chorioretinopathy and uveitis and guide the development of new therapeutic approaches by microbiome-altering interventions for these diseases

Laparoscopic gastric banding.

INTRODUCTION: Laparoscopic gastric banding (LGB) is currently the most popular purely restrictive bariatric operation in Europe and many other countries. It has a low operative morbidity, but is associated with a substantial late complication rate. Many late complications have been attributed to technical errors or to the learning curve. The aim of this paper is to present our results with gastric banding after the learning curve in order to disclose the true incidence of long-term complications. METHODS: LGB was introduced in our department in December 1995. Thirty patients were operated on until June 1997 using the early banding technique (band within the lesser sac), at which time the surgical technique was slightly modified in order to place the band above the lesser sac. Then another 300 patients underwent LGB using either the Lapband or the SAGB system. This report focuses on the latter patients. All the data were collected prospectively. RESULTS: The series includes 300 patients (257 women and 43 men) with a mean age of 38.3 years (19-64). The mean initial weight was 119.2 kg (57-179), initial body mass index (BMI) was 43.3 kg/m2 (21-64), and initial excess weight was 96.5% (0-191). The mean duration of surgery was 90 min, decreasing over time to a mean of 75 min for the last 50 cases. Early overall morbidity was 6.6%. Major complications occurred in 7 patients (2.3%). Excess weight loss (EWL) was at least 50% in 66% of the patients after 2 years, averaging 60%, with no substantial change until 4 years, and the BMI stabilized between 30 and 31 kg/m2. Forty-nine patients developed a total of 52 long-term complications, of which 23 (7.6%) were related only to the port or catheter. Band erosion occurred in 17 (5.6%), pouch dilatation with slippage in 8 (2.6%), and infection in 4 (1.3%) patients. Fifty-five reoperations were necessary. Twenty-five of these were related only to the port. The band was removed from 26 (9%) patients, of whom 17 were converted to Roux-en-Y gastric bypass. CONCLUSIONS: LGB gives satisfactory results in terms of weight loss in about two-thirds of the patients. Even beyond the learning curve, the long-term morbidity is not negligible, but is acceptable compared to other procedures such as vertical banded gastroplasty. Conversion to gastric bypass is possible when complications occur and can be performed when the band is removed in most cases

Precision of bone mechanoregulation assessment in humans using longitudinal high-resolution peripheral quantitative computed tomography in vivo.

Local mechanical stimuli in the bone microenvironment are essential for the homeostasis and adaptation of the skeleton, with evidence suggesting that disruption of the mechanically-driven bone remodelling process may lead to bone loss. Longitudinal clinical studies have shown the combined use of high-resolution peripheral quantitative computed tomography (HR-pQCT) and micro-finite element analysis can be used to measure load-driven bone remodelling in vivo; however, quantitative markers of bone mechanoregulation and the precision of these analyses methods have not been validated in human subjects. Therefore, this study utilised participants from two cohorts. A same-day cohort (n = 33) was used to develop a filtering strategy to minimise false detections of bone remodelling sites caused by noise and motion artefacts present in HR-pQCT scans. A longitudinal cohort (n = 19) was used to develop bone imaging markers of trabecular bone mechanoregulation and characterise the precision for detecting longitudinal changes in subjects. Specifically, we described local load-driven formation and resorption sites independently using patient-specific odds ratios (OR) and 99 % confidence intervals. Conditional probability curves were computed to link the mechanical environment to the remodelling events detected on the bone surface. To quantify overall mechanoregulation, we calculated a correct classification rate measuring the fraction of remodelling events correctly identified by the mechanical signal. Precision was calculated as root-mean-squared averages of the coefficient of variation (RMS-SD) of repeated measurements using scan-rescan pairs at baseline combined with a one-year follow-up scan. We found no significant mean difference (p < 0.01) between scan-rescan conditional probabilities. RMS-SD was 10.5 % for resorption odds, 6.3 % for formation odds, and 1.3 % for correct classification rates. Bone was most likely to be formed in high-strain and resorbed in low-strain regions for all participants, indicating a consistent, regulated response to mechanical stimuli. For each percent increase in strain, the likelihood of bone resorption decreased by 2.0 ± 0.2 %, and the likelihood of bone formation increased by 1.9 ± 0.2 %, totalling 38.3 ± 1.1 % of strain-driven remodelling events across the entire trabecular compartment. This work provides novel robust bone mechanoregulation markers and their precision for designing future clinical studies

Evaluation of Load-To-Strength Ratios in Metastatic Vertebrae and Comparison With Age- and Sex-Matched Healthy Individuals.

Vertebrae containing osteolytic and osteosclerotic bone metastases undergo pathologic vertebral fracture (PVF) when the lesioned vertebrae fail to carry daily loads. We hypothesize that task-specific spinal loading patterns amplify the risk of PVF, with a higher degree of risk in osteolytic than in osteosclerotic vertebrae. To test this hypothesis, we obtained clinical CT images of 11 cadaveric spines with bone metastases, estimated the individual vertebral strength from the CT data, and created spine-specific musculoskeletal models from the CT data. We established a musculoskeletal model for each spine to compute vertebral loading for natural standing, natural standing + weights, forward flexion + weights, and lateral bending + weights and derived the individual vertebral load-to-strength ratio (LSR). For each activity, we compared the metastatic spines' predicted LSRs with the normative LSRs generated from a population-based sample of 250 men and women of comparable ages. Bone metastases classification significantly affected the CT-estimated vertebral strength (Kruskal-Wallis, p < 0.0001). Post-test analysis showed that the estimated vertebral strength of osteosclerotic and mixed metastases vertebrae was significantly higher than that of osteolytic vertebrae (p = 0.0016 and p = 0.0003) or vertebrae without radiographic evidence of bone metastasis (p = 0.0010 and p = 0.0003). Compared with the median (50%) LSRs of the normative dataset, osteolytic vertebrae had higher median (50%) LSRs under natural standing (p = 0.0375), natural standing + weights (p = 0.0118), and lateral bending + weights (p = 0.0111). Surprisingly, vertebrae showing minimal radiographic evidence of bone metastasis presented significantly higher median (50%) LSRs under natural standing (p < 0.0001) and lateral bending + weights (p = 0.0009) than the normative dataset. Osteosclerotic vertebrae had lower median (50%) LSRs under natural standing (p < 0.0001), natural standing + weights (p = 0.0005), forward flexion + weights (p < 0.0001), and lateral bending + weights (p = 0.0002), a trend shared by vertebrae with mixed lesions. This study is the first to apply musculoskeletal modeling to estimate individual vertebral loading in pathologic spines and highlights the role of task-specific loading in augmenting PVF risk associated with specific bone metastatic types. Our finding of high LSRs in vertebrae without radiologically observed bone metastasis highlights that patients with metastatic spine disease could be at an increased risk of vertebral fractures even at levels where lesions have not been identified radiologically

Regional sociocultural differences as important correlate of physical activity and sedentary behaviour in Swiss preschool children

Regional differences in physical activity in school-aged children and adults even within one country with the same political and health care system have been observed and could not be explained by sociodemographic or individual variables. We analysed whether such differences were already present in preschool children.; Swiss children from 84 childcare centres in five cantons (Aargau, Bern, Fribourg, Vaud, Zurich) comprising about 50% of the population of the country participated. Physical activity was quantified with accelerometers (ActiGraph, wGT3X-BT) and potential correlates were assessed with measurements at the childcare centre or questionnaires. Mixed regression models were used to test associations between potential correlates of total physical activity (TPA), moderate-to-vigorous physical activity (MVPA), light physical activity (LPA) or sedentary behaviour with a special focus on regional differences.; 394 of 476 children (83%) provided valid physical activity data (at least 2 weekdays and 1 weekend day with 10 h recording; mean age 3.9 ± 0.7 years, 54% boys) with 26% and 74% living in the French- and German-speaking parts of Switzerland, respectively. Days consisted of (mean ± standard deviation) 1.5 ± 0.5 h MVPA, 5.0 ± 0.6 h LPA, and 6.3 ± 0.8 h sedentary behaviour with an average of 624 ± 150 counts/min TPA. TPA and MVPA (but not sedentary behaviour or LPA) increased with age, were higher in boys and children with better motor skills. Despite controlling for individual characteristics, familial factors and childcare exposure, children from the French-speaking part of Switzerland showed 13% less TPA, 14% less MVPA, 6% less LPA and 8% more sedentary behaviour than German-speaking children.; Beside motor skills and non-modifiable individual factors, the regional sociocultural difference was the most important correlate of phyical activity and sedentary behaviour. Therefore, regionally adapted public health strategies may be needed

The Swiss Preschoolers’ health study (SPLASHY): objectives and design of a prospective multi-site cohort study assessing psychological and physiological health in young children

Background: Children’s psychological and physiological health can be summarized as the child’s thinking, feeling, behaving, eating, growing, and moving. Children’s psychological and physiological health conditions are influenced by today’s life challenges: Thus, stress exposure and lack of physical activity represent important health challenges in older children. However, corresponding evidence for young children is scarce. The aim of Swiss Preschoolers’ Health Study (SPLASHY) is to examine the role of stress and physical activity on children’s psychological and physiological health, particularly on cognitive functioning, psychological well-being, adiposity and motor skills in children at an early stage of childhood. We will also assess the role of child and environmental characteristics and aim to define sensitive time points. Methods/design: In a total of 84 child care centers, children at preschool age (2–6 years) are recruited and are assessed immediately and one year later. Assessments include direct measurements of the children in the child care centers and at home as well as assessments of children’s behavior and environmental factors through informants (parents and child care educators). Discussion: SPLASHY is one of the first studies in early childhood aiming to investigate the influence of stress and physical activity on children’s psychological and physiological health in a community-based longitudinal design

The relationship of parenting style and eating behavior in preschool children

Background: Eating behavior represents individual appetitive traits which are related to the individual's regulation of food intake. Eating behavior develops at an early age. There is some evidence that parenting styles might impact on the child's eating behavior. The aim of this study was to investigate the relationship of different dimensions of positive and negative parenting styles with the child's eating behavior at a critical age period of the child's early development. Methods: Parents of 511 preschool children (aged 2-6 years) completed the Children Eating Behavior Questionnaire and the Alabama Parenting Questionnaire. Results: Analyses revealed that different dimensions of negative parenting styles were associated with eating behavior of the child. In details, inconsistent parenting showed a consistent association with eating behavior of a child (i.e. higher emotional eating, higher food responsiveness, higher food fussiness, higher satiety responsiveness and more enjoyment of food), whereas corporal punishment was associated with more emotional overeating and more food responsiveness but less satiety responsiveness. Further, powerful implementation was related to higher food responsiveness and less enjoyment of food and low monitoring was associated with higher emotional overeating and more slowness in eating. There was no such consistent association of positive parenting and eating behavior. Conclusions: More negative parenting styles were associated with eating behavior which is more often related to potential weight problems in a long term, whereas positive parenting did not show such a consistent relationship with eating behavior. Negative parenting should be in the focus of prevention and treatment of eating behavior problems in young children. Trial registration: ISRCTN41045021 (06/05/2014). Keywords: Eating behavior; Parenting style; Preschool; SPLASH