Initial Weight Loss Research Articles

Association of short-term and long-term weight loss with the risk of major adverse cardiovascular disease: Community-based cohort study

BackgroundThis study evaluated temporal association of changes in BMI over time with major adverse cardiovascular event (MACE) in Korean middle-aged adults. MethodsBetween 2001 and 2002, 6855 individuals from the Korean Genome and Epidemiology Study were included and followed up until 2014. The main predictor was the change in BMI determined using group-based trajectory modelling (decreasing, stable, and increasing) from the baseline to 4-, 6-, and 8-years of follow-up. The primary outcome was the occurrence of MACE. ResultsDuring the mean 10.2 years follow-up, MACEs occurred in 350 (5.1 %) individuals. The median (interquartile rage) age of study population was 50 (44–59) years. In primary analysis with 4-year trajectory model, decreasing BMI trajectory was associated with a 1.41-fold higher risk of the MACEs (hazard ratio [HR], 1.41; 95 % confidence interval [CI], 1.06–1.91) compared with stable BMI trajectory. In secondary analyses with 6- and 8-year trajectory models, this association disappeared, and the corresponding HRs (95 % CIs) were 1.14 (0.81–1.61) and 0.98 (0.65–1.49), respectively. There were concomitant improvements in cardiometabolic risk factors in decreasing BMI group, but unfavorable risk burden remained up to 4 to 6 years. ConclusionsThe initial 4-year weight loss was paradoxically associated with a higher risk of MACEs, probably due to residual cardiovascular burden. However, this association became null in participants with sustained weight loss ≥ 6 years, suggesting a possible lag effect of weight loss on MACEs.

Diastolic function and cardiovascular risk among patients with severe obesity referred to a lifestyle-program – a pilot study

Objectives. Severe obesity is associated with a high risk of comorbidities and alterations of cardiac structure and function. The primary aim of the study was to investigate the proportion of diastolic dysfunction (DD) at baseline, and changes in cardiac function from baseline (T1) to 6 months follow-up (T2) among participants with severe obesity attending a lifestyle-intervention. The secondary aim was to explore changes in body mass index (BMI), physical fitness (VO2peak) and cardiovascular risk from T1 to T2 and 12 months follow-up (T3). Design. This was an open single-site prospective observational study. Patients were recruited from an obesity clinic to a lifestyle-intervention consisting of three 3-weeks intermittent stays over 12-months period. Echocardiography was performed at T1 and T2 and BMI, VO2peak and cardiovascular risk measured at T1, T2 and T3. Results. Fifty-six patients were included (mean age 45.1 years; BMI 41.9). Six of 52 patients (12%) had grade 1 DD at T1, while five subjects had DD at T2. E/A ratio (11%, p = .005) and mitral deceleration time (9%, p = .014) were improved at T2. A reduction in BMI (–1.8, p < .001) and improvement in VO2peak (1.6 mL/kg min, p = .026) were assessed at T2 and this improvement persisted at T3. The total cardiovascular risk score was not significantly changed. Conclusion. The patients with severe obesity had low prevalence of DD. For all participants, an improvement in diastolic parameters, and an important initial weight loss was observed. Clinical Trial number: NCT02826122

Microencapsulated phase change n-Octadecane with high heat storage for application in building energy conservation

A novel type of microencapsulated phase change materials (microPCMs) with n-Octadecane core shelled by styrene–divinylbenzene copolymer were synthesized by the suspension polymerization. The morphologies and chemical compositions of the microPCMs with four different shell-to-core ratios were analyzed via the scanning electron microscopy and Fourier transform infrared spectroscopy. Based on the measurements from the thermogravimetric analyzers and differential scanning calorimetry, the thermal characteristics of the different microPCMs were analyzed. The results show that the sample microPCMs with 2:1 shell-to-core ratio (microPCM3) has good thermal stability and high heat storage capability, with melting enthalpy and encapsulation efficiency measured at 111.5 ± 0.7 J/g and 51.4 ± 0.7 %, respectively, which are the highest among all the prepared samples. The initial weight loss temperature of the microPCM3 increases to 160.5 ℃ compared to 115.5 ℃ for the pure n-Octadecane. Furthermore, we prepared four different building boards with different microPCM3 contents (0, 10, 20, or 30 wt%) in cement matrix. Compared to the conventional building material, the board with 30 wt% microPCM3 can store 67.82% more heat energy in the typical temperature range of 10–50 °C. We investigated the passive cooling and heating effects of the boards under extreme temperature conditions (10–70 °C), as well as their thermal regulation performance under multiple consecutive thermal cycling experiments. Compared with the cement board without addition of microPCM3, the board with 30 wt% microPCM3 has reduced temperature fluctuation by 59.0% with maximum temperature fluctuation only 23.5 °C. It has shown excellent thermal regulation and thermal insulation properties and is of great application potential in energy-saving buildings.

Abstract 11438: The Inflammatory Proteome, Obesity, and Medical Weight Loss in Humans

Introduction: Most individuals regain weight after medical weight loss via “metabolic adaptation,” the mechanism of which remains unclear. Here, we studied the relation of circulating inflammatory proteins with weight loss and regain to identify a role for inflammation in metabolic adaptation. Methods: We analyzed 74 proteins related to inflammation and native immune regulation (Olink) in plasma from a maximum of 490 participants serially in a trial of medical weight loss maintenance. Linear and mixed effects regression models and t -tests were used to measure cross-sectional and longitudinal association of proteins with weight, with replication in the Framingham Heart Study (FHS). Results: Subjects included (60% women, 35% African American) had initial median weight of 94 kg, with a median loss 8 kg over 6 months of supervised medical weight loss, with subsequent median regain 2 kg over 30 months. We observed broad changes in inflammatory proteins with initial weight loss, many of which also tracked with weight regain (e.g. hepatocyte growth factor, interleukin-18, colony stimulating factor 1; Figure ). While many proteins have been implicated in weight regulation from mouse/human models, several are novel. Proteins associated with weight change involve pathways of angiogenesis, cell cycle regulation and immune response and are secreted from lung, adipose tissue, smooth muscle and others. Several proteins specifying chemotaxis and innate immune responses were associated with different rates of weight regain. Association with prevalent (but not incident) obesity was replicated for several proteins in the FHS. Conclusions: Broad changes in the inflammatory state track with weight (and its change during medical therapy) and may identify specific pathways that modify risk of weight regain. Further studies of innate immune activation in metabolic adaptation in humans to limit weight regain are warranted.

The Timing of Pregnancies After Bariatric Surgery has No Impact on Children’s Health—a Nationwide Population-based Registry Analysis

PurposeBariatric surgery has a favorable effect on fertility in women. However, due to a lack of data regarding children’s outcomes, the ideal time for conception following bariatric surgery is unknown. Current guidelines advise avoiding pregnancy during the initial weight loss phase (12–24 months after surgery) as there may be potential risks to offspring. Thus, we aimed to analyze health outcomes in children born to mothers who had undergone bariatric surgery. The surgery-to-delivery interval was studied.Materials and MethodsA nationwide registry belonging to the Austrian health insurance funds and containing health-related data claims was searched. Data for all women who had bariatric surgery in Austria between 01/2010 and 12/2018 were analyzed. A total of 1057 women gave birth to 1369 children. The offspring’s data were analyzed for medical health claims based on International Classification of Diseases (ICD) codes and number of days hospitalized. Three different surgery-to-delivery intervals were assessed: 12, 18, and 24 months.ResultsOverall, 421 deliveries (31%) were observed in the first 2 years after surgery. Of these, 70 births (5%) occurred within 12 months after surgery. The median time from surgery to delivery was 34 months. Overall, there were no differences noted in frequency of hospitalization and diagnoses leading to hospitalization in the first year of life, regardless of the surgery-to-delivery interval.ConclusionPregnancies in the first 24 months after bariatric surgery were common. Importantly, the surgery-to-delivery interval had no significant impact on the health outcome of the children.Graphical

Weight regain after behavioural weight management programmes and its impact on quality of life and cost effectiveness: Evidence synthesis and health economic analyses.

We used data from a recent systematic review to investigate weight regain after behavioural weight management programmes (BWMPs, sometimes referred to as lifestyle modification programmes) and its impact on quality-of-life and cost-effectiveness. Trial registries, databases and forward-citation searching (latest search December 2019) were used to identify randomized trials of BWMPs in adults with overweight/obesity reporting outcomes at ≥12 months, and after programme end. Two independent reviewers screened records. One reviewer extracted data and a second checked them. The differences between intervention and control groups were synthesized using mixed-effect, meta-regression and time-to-event models. We examined associations between weight difference and difference in quality-of-life. Cost-effectiveness was estimated from a health sector perspective. In total, 155 trials (n > 150 000) contributed to analyses. The longest follow-up was 23 years post-programme. At programme end, intervention groups achieved -2.8kg (95%CI -3.2 to -2.4) greater weight loss than controls. Weight regain after programme end was 0.12-0.32 kg/year greater in intervention relative to control groups, with a between-group difference evident for at least 5 years. Quality-of-life increased in intervention groups relative to control at programme end and thereafter returned to control as the difference in weight between groups diminished. BWMPs with this initial weight loss and subsequent regain would be cost-effective if delivered for under £560 (£8.80-£3900) per person. Modest rates of weight regain, with persistent benefits for several years, should encourage health care practitioners and policymakers to offer obesity treatments that cost less than our suggested thresholds as a cost-effective intervention to improve long-term weight management. The review is registered on PROSPERO, CRD42018105744.

Investigation of the catalytic performance of coal gangue char on biomass pyrolysis in a thermogravimetric analyzer and a fixed bed reactor

• Coal gangue rich in metals was used to prepare char-supported catalysts. • Coal gangue char can reduce the activation energy required for pine pyrolysis. • The yield of gas increased with the increase of the coal gangue char mass ratio. • The liquid product yields decreased by 19.01% at PS and CG mass ratio of 1:2. Developing low-cost and high-performance catalysts is an important part of the development of biomass pyrolysis technologies. In this study, the coal gangue rich in metals was used to directly prepare a char-supported catalyst, and metals in coal gangue were hoped to act as catalytic sites for in-situ biomass catalytic pyrolysis and secondary tar cracking. The influence of coal gangue char on pine pyrolysis behavior and kinetics was investigated in the thermogravimetric analyzer and a fixed bed reactor. The thermogravimetric analysis showed that the addition of coal gangue char caused the movement of the initial weight loss temperature and the maximum weight loss peak of the samples to the high-temperature region. With the increase of the coal gangue char mass ratio, lower apparent activation energies of the samples were achieved in the conversion range of 0.2–0.8. Through fixed-bed isothermal pyrolysis experiments, it was found that the yield of gas increased with the increase of the coal gangue char mass ratio, while the tar yield decreased quickly. The yield of H 2 and CO was significantly improved by the coal gangue char, further confirming the catalytic performance of coal gangue char on the cracking of tar molecules.

Initial BMI and Weight Loss over Time Predict Mortality in Parkinson Disease.

Although weight loss is a frequent symptom in Parkinson disease (PD), there have been few studies on the association between body mass index (BMI) and mortality. The objective of this study was to investigate the association between BMI and change in BMI at diagnosis in patients with PD and all-cause mortality. Cohort study using Korean National Health Insurance Service-Elderly Cohort data. Patients with new-onset PD were selected using the International Classification of Diseases 10th edition code (G20). Then, patients who were diagnosed more than 3 times with PD and had been prescribed anti-parkinsonian medication for ≥30days were included. Those with a combined diagnosis of atypical parkinsonism and secondary parkinsonism were excluded. The primary outcome was all-cause mortality. Anthropometric data, including height and weight, were obtained from the health screening data to calculate BMI. The Cox proportional hazards model was used to assess mortality risk by BMI. Among the 2703 patients with PD, 492 (18.20%) died during the 11-year follow-up period. There was a significant inverse dose-response relationship between baseline BMI and mortality [<18.5kg/m2: hazard ratio (HR), 1.872, 95% CI, 1.338-2.494; 23-25kg/m2: HR, 0.695, 95% CI, 0.546-0.886; 25-30kg/m2: HR, 0.644, 95% CI, 0.476-0.869; ≥30kg/m2: HR, 0.396, 95% CI, 0.165-0.950]. Change in BMI of 10% revealed a significant association with mortality. Subgroup analyses by sex showed a significant inverse dose-response relationship between BMI and all-cause mortality only in women. We demonstrated an inverse dose-response association between BMI at diagnosis and mortality in patients with PD, especially in women. Early detection of PD before weight loss progression and proper management might improve mortality. The small number of obese PD participants in our study should be considered when interpreting and generalizing results.

High-rate of long-term revision surgery due to weight regain after Laparoscopic Gastric Greater Curvature Plication (LGGCP)

PurposeTo present the long-term clinical outcomes of laparoscopic gastric greater curvature plication (LGGCP) in terms of weight loss and revision surgery rate. Material and methodsThis single-center study involved a retrospective analysis of patients that underwent revision surgery after LGGCP due to weight regain. Demographic and anthropometric data, comorbidities, operation time, hospital stays, mortalities, and immediate and long-term postoperative complications were analyzed. Postoperative Body Mass Index (BMI), %total weight loss (TWL), and complications were collected during follow-up. ResultsOf the 75 patients that underwent LGGCP at our hospital from March 2013 to February 2016, 13 (13/75, 17.3%) underwent revision surgery. All patients except one opted for sleeve gastrectomy. The mean interval between LGGCP and revision surgery was 71.0 ± 12.0 months (range, 54.8–93.6), and mean body weight, BMI, and TWL at revision were 89.2 ± 11.3 kg, 33.9 ± 4.2 kg/m2, and 4.7 ± 9.3%, respectively. The main reason for revision was weight regain. Additional problems were chronic intermittent GERD (4/13, 30.8%), dyspepsia (4/13,30.8%), and chronic relapsing melena (1/13, 7.7%). Two patients experienced immediate postoperative complications (Clavien-Dindo II and III). At one year after revision surgery, the mean body weight, BMI, and additional %TWL from revision surgery were 63.0 ± 5.3 kg, 24.0 ± 2.9 kg/m2, and 28.7 ± 8.0%, respectively. One of four patients (1/4, 25%) that complained of GERD before revision surgery, was still on PPI medication at 1 year after revision surgery. ConclusionAlthough LGGCP showed initial acceptable weight loss outcomes, long term (>5 years) follow-up showed that LGGCP is associated with a high rate of revision surgery (17.3%) due to weight regain.

Effects of low-calorie and different weight-maintenance diets on IgG glycome composition.

Obesity-induced inflammation activates the adaptive immune system by altering immunoglobulin G (IgG) glycosylation in a way to produce more proinflammatory antibodies. The IgG glycome has already been well studied, and its alterations are correlated with a high body mass index (BMI) and central adiposity. Still, the IgG N-glycome susceptibility to different dietary regimes for weight control after the initial weight loss has not been studied. To explore changes in IgG glycosylation induced by weight loss and subsequent weight-maintenance diets, we analyzed 1,850 IgG glycomes from subjects in a dietary intervention Diogenes study. In this study, participants followed a low-calorie diet (LCD) providing 800 kcal/d for 8 weeks, followed by one of five weight-maintenance diets over a 6-month period. The most significant alteration of the IgG N-glycome was present 8 weeks after the subjects underwent an LCD, a statistically significant decrease of agalactosylated and the increase of sialylated N glycans. In the follow-up period, the increase in glycans with bisecting GlcNAc and the decrease in sialylated glycans were observed. Those changes were present regardless of the diet type, and we did not observe significant changes between different diets. However, it should be noted that in all five diet groups, there were individuals who prominently altered their IgG glycome composition in either proinflammatory or anti-inflammatory directions.

Biofuel characteristics of chars produced from rapeseed, whitewood, and seaweed via thermal conversion technologies – Impacts of feedstocks and process conditions

Understanding the suitability of different conversion technologies for different types of biomass feedstocks is crucial in delivering the full valorisation of different types of biomass feedstocks. Optimal valorisation pathways can be identified by investigating the formation of products and the most efficient application technologies of these products. This is therefore novel research reporting an extensive comparative study on the biomass processing pathways (hydrothermal conversion, pyrolysis, and torrefaction) for three distinct biomass feedstocks (Rapeseed residue, Whitewood, Seaweed–Laminaria Digitata) to optimise char formation under a wide range of processing conditions and their biofuel characteristics in the bioenergy applications. The results demonstrates that Whitewood gradually decomposes during all three conversion processes to produce chars (hydrochars/biochars) that have a lower O/C-H/C ratio as process temperature increases. The char formation from Whitewood follows the dehydration process in the Van Krevelen diagram. Char formation from Rapeseed residue and L. digitata via pyrolysis also follows a similar dehydration and demethanation pathway at higher temperatures (550 °C for Rapeseed residue and 400 °C for L. digitata). However, char formation from Rapeseed residue and L. digitata via hydrothermal conversion predominantly follows the decarboxylation pathway producing structures with a higher H/C ratio and lower O/C ratio. The intrinsic reactivity analysis of these chars showed that the temperature of initial weight loss and the onset of ignition for the raw biomass sample was shifted to a higher temperature for the chars produced by hydrothermal conversion or pyrolysis, regardless of biomass feedstocks. The chars produced from Whitewood (with hydrothermal conversion, pyrolysis and torrefaction) and Rapeseed residue (with pyrolysis) have a potential application in bioenergy production due to the significant enhancement of char products. However, the chars produced from L. digitata appear less promising for bioenergy applications due to relatively low energy yield, carbon recovery, inferior char structures and a high inherent ash content.

Patterns of body weight change affect weight loss during a multidisciplinary intervention in adolescents with obesity

AimThe current pediatric obesity health challenge necessitates a better understanding of the factors affecting weight loss success during interventions. The aim of this observational study was to test the impact of the rate of initial weight loss and body weight variability on weight loss during a 9-month residential, multidisciplinary weight loss program in adolescents with obesity. MethodsThis retrospective study considered a whole sample of 510 adolescents with obesity (12–16 years, 435 girls). Body weight assessment was performed before (T0) and each week during the 9 months of a multidisciplinary weight loss program. Initial weight change (week 4-W4) and overall weight change at week 12 (T1) and the end of the intervention (T2) were considered. Participants were divided into three groups (tertiles), based on their percentage of weight loss between T0 and W4; and weight variability was expressed by the root mean square error (RMSE) around each participant’s regression line at each considered period (W4, T1, T2). ResultsAdolescents with lower initial weight loss at W4 (tertile 3) displayed the lesser weight loss at T1 and T2 compared with adolescents in tertile 1 and 2. The RMSE was positively associated with the percentage of weight loss of the period considered, but when the analyses were adjusted for age and initial body weight, there was no more significant association. ConclusionsThe rate of weight loss during the first few weeks is crucial for weight loss success, and weight variability is positively associated with weight loss in adolescents with obesity. Overall, results show that initial body weight is a determinant characteristic to consider during a lifestyle intervention. Further studies are thus needed to better understand the relationship between body weight change patterns and weight loss during the dynamic state that is adolescence.

A novel bio‐based, flame retardant and latent imidazole compound—Its synthesis and uses as curing agent for epoxy resins

AbstractComposite industry is constantly seeking multifunctional, high performance and environmentally friendly materials. Herein reported is a novel bio‐based, flame retardant and latent epoxy curing agent synthesized from wood vanillin, phosphate ester and imidazole. Experiment data from combustion test demonstrated that the cured epoxy resin with this new curing agent, designated as VAIP, rendered effective flame retardant property with limit of oxygen of 38.4%, UL‐94 V‐0 rating, total heat release of 48 MJm−2 and peak heat release rate of 435 KWm−2. Thermal mechanical tests showed its significantly higher char yield of 35% at 800°C and thermal stability with the temperature of initial weight loss rate of above 350°C, compared to reference epoxy resins cured by conventional cyano‐imidazole (CEMI). This new phosphorus containing imidazole curing agent also demonstrated potential application in fiber‐reinforced composite by rendering comparable Tg, for both dry and hot‐wet conditions, as well as higher interlaminar and shear strengths, when compared with the reference composite. Dynamic rheological isothermal measurement of the epoxy resin viscosity further concluded that VAIP had significantly better latency of 580 min at 60°C and 14 days at room temperature, resulting in much longer pot life or shelf life for the formulated resins and their prepreg.

Study on the combustion characteristics of bituminous coal modified by typical inorganic acids

Acid fracturing technology is applied to increase the permeability of coal seams to promote gas extraction, but the effects of acid solutions on coal combustion cannot be ignored. This paper focuses on HF, HCl, and HNO3. The Bagchi method determines the mechanism function of each nonisothermal TG stage of acidified coal. Combining FTIR, TG-DTA, and KTA, this paper studies the combustion performance of acidified coal from the perspectives of the coal molecular structure evolution, combustion phenomenon, and kinetics. The results show that inorganic acids can destroy C=O in coal, resulting in the carbonyl groups in the HF, HCl, and HNO3 samples decreasing to 21%, 35%, and 0% of that in the RAW samples, respectively. Inorganic acid significantly enhances the reaction rate and thermal effect of combustion stage and improves the comprehensive combustion performance of coal, and the effect is in the order of HF > HNO3>HCl. Inorganic acids change the most likely mechanism function of initial weight loss stage. The oxidation increase of the HNO3 sample is greater than the corrosion weight loss, resulting in a corrosion ratio of −1.74%. HF and HCl reduce the activation energy of oxidation weight gain stage and increase the spontaneous combustion tendency of coal samples.

Preparation and structure-properties of crosslinking organic montmorillonite/polyurethane as solid-solid phase change materials for thermal energy storage

In order to solve the leakage problem of commonly used polyethylene glycol (PEG) phase change material (PCM), PEG reacted with 4′ 4-diphenylmethane diisocyanate (MDI) to prepare the polyurethane-based solid-solid phase change material (PU-SSPCM) by the two-step solvent method, and the influence of organic montmorillonite (OMMT) on the phase transition property and crystallization capacity of PU-SSPCM was first studied. The solid-solid phase change polyurethane materials were successfully prepared when the molar ratio of PEG to MDI was 0.75, and the organic montmorillonite acted as a crosslinking heterogeneous nucleating agent to improve the temperature control capacity, the crystallization ability and the thermal stability of the solid-solid phase change polyurethane material. When the addition of OMMT was 0.5 wt%, the phase change enthalpy of PU-SSPCM increased to 106.8J/g from 95.46J/g, a constant temperature platform appeared for about 300 s during both the heating and cooling process, thus demonstrating excellent temperature control ability. The relative crystallinity increased to 74.8% from 66.5% and the initial thermal weight loss temperature was increased from 348 °C to 368 °C. • Organic montmorillonite acted as a crosslinking heterogeneous nucleating agent. • Organic montmorillonite enhanced the temperature control capacity the system. • The composites possessed excellent crystallization ability and thermal stability.

The Extent of Lifestyle-Induced Weight Loss Determines the Risk of Prediabetes and Metabolic Syndrome Recurrence during a 5-Year Follow-Up.

It is controversial whether lifestyle-induced weight loss (LIWL) intervention provides long-term benefit. Here, we investigated whether the degree of weight loss (WL) in a controlled LIWL intervention study determined the risk of prediabetes and recurrence of metabolic syndrome (MetS) during a 5-year follow-up. Following LIWL, 58 male participants (age 45–55 years) were divided into four quartiles based on initial WL: Q1 (WL 0–8.1%, n = 15), Q2 (WL 8.1–12.8%, n = 14), Q3 (WL 12.8–16.0%, n = 14), and Q4 (WL 16.0–27.5%, n = 15). We analyzed changes in BMI, HDL cholesterol, triglycerides (TGs), blood pressure, and fasting plasma glucose (FPG) at annual follow-up visits. With a weight gain after LIWL between 1.2 (Q2) and 2.5 kg/year (Q4), the reduction in BMI was maintained for 4 (Q2, p = 0.03) or 5 (Q3, p = 0.03; Q4, p < 0.01) years, respectively, and an increase in FPG levels above baseline values was prevented in Q2–Q4. Accordingly, there was no increase in prediabetes incidence after LIWL in participants in Q2 (up to 2 years), Q3 and Q4 (up to 5 years). A sustained reduction in MetS was maintained in Q4 during the 5-year follow-up. The present data indicate that a greater initial LIWL reduces the risk of prediabetes and recurrence of MetS for up to 5 years.

Are the Effects of Malnutrition on the Gut Microbiota–Brain Axis the Core Pathologies of Anorexia Nervosa?

Anorexia nervosa (AN) is a disabling, costly, and potentially deadly illness. Treatment failure and relapse after treatment are common. Several studies have indicated the involvement of the gut microbiota–brain (GMB) axis. This narrative review hypothesizes that AN is driven by malnutrition-induced alterations in the GMB axis in susceptible individuals. According to this hypothesis, initial weight loss can voluntarily occur through dieting or be caused by somatic or psychiatric diseases. Malnutrition-induced alterations in gut microbiota may increase the sensitivity to anxiety-inducing gastrointestinal hormones released during meals, one of which is cholecystokinin (CCK). The experimental injection of a high dose of its CCK-4 fragment in healthy individuals induces panic attacks, probably via the stimulation of CCK receptors in the brain. Such meal-related anxiety attacks may take part in developing the clinical picture of AN. Malnutrition may also cause increased effects from appetite-reducing hormones that also seem to have roles in AN development and maintenance. The scientific background, including clinical, microbiological, and biochemical factors, of AN is discussed. A novel model for AN development and maintenance in accordance with this hypothesis is presented. Suggestions for future research are also provided.

Long-Term Weight Loss Outcome of Laparoscopic Sleeve Gastrectomy Predicted by the Percentage of Excess Weight Loss at 6 Months in Chinese Patients with Body Mass Index ≥ 32.5 Kg/m2.

PurposeTo evaluate the predictive effect of the initial weight loss on the long-term weight loss in Chinese patients with a body mass index (BMI) ≥ 32.5 kg/m2 who underwent LSG.Patients and MethodsThe follow-up was completed via phone or WeChat for outpatients and at the hospital for inpatients. We evaluated the BMI, percentage of excess weight loss (%EWL), and type 2 diabetes mellitus, hypertension, and hyperlipidemia statuses. Linear and logistic regression analyses were performed on the relationship between the initial and long-term weight loss. The optimal cut-off value was determined by receiver operating characteristic (ROC) curve analysis.ResultsWe enrolled 307 patients, with a median preoperative BMI of 39.68 (35.68, 45.47) kg/m2. %EWL ≥ 50% was regarded as successful weight loss, and 76.55% of the patients lost their weight successfully. (Reviewer #1, comment #4) %EWL at 6 months and 5 years were positively correlated (P < 0.001). Further, the following linear equation could express the relationship: (%EWL5 years = 29.193 + 0.526 × %EWL6 months). %EWL ≥ 58.57% at 6 months was the best predictor of successful weight loss at 5 years after LSG (Reviewer #1, comment #5) (sensitivity, 73.62%; specificity, 73.61%; AUC value, 0.780). Internal verification of the prediction model revealed satisfactory results in terms of discrimination and calibration.ConclusionIn Chinese patients with BMI ≥ 32.5 kg/m2 who underwent LSG, %EWL at 6 months and 5 years were correlated. %EWL ≥ 58.57% at 6 months was a predictor of successful long-term weight loss.

Autopsy of Used Reverse Osmosis Membranes from the Largest Seawater Desalination Plant in Oman.

The Barka desalination plant, commissioned in 2018, is the largest desalination plant in Oman. It has a capacity of 281 MLD with a reverse osmosis (RO) first-pass recovery rate of 46%. As part of the standard operator practice, a membrane autopsy was conducted to determine the cause of reductions in membrane performance. This study investigated fouled membranes (model No. SW30HRLE-440) from two different locations in the membrane rack. Various analytical methods were used to conduct the membrane autopsy. Field-emission scanning electron microscopy/energy-dispersive X-ray (FESEM/EDS) analyses of membrane samples showed major components of inorganic foulants. Moreover, black and salt-like crystals deposited on the membrane surface revealed significant carbon (C) components and oxygen (O), with a small amount of magnesium (Mg), chloride (Cl), sodium (Na), aluminium (Al), and calcium (Ca), respectively. A Fourier transform infrared (FTIR) analysis revealed the presence of long-chain hydrocarbons, carboxylic acids/esters, carbohydrates/polysaccharides, and inorganic foulants. Thermogravimetric analyses (TGA) of the membranes showed a high initial weight loss due to organic and inorganic fouling. X-ray photoelectron (XPS) analyses further confirmed the presence of inorganic and organic foulants on the membrane surfaces. Bacteria identification results showed the presence of Bacillus cereus and Bacillus marisflavi. This paper offers a detailed analysis of the foulants present on the reverse osmosis membrane surface and sub-surface before and after a cleaning process.

Revision of Gastric Plication to Gastric Bypass (Indications and Solutions)

BACKGROUND: Laparoscopic gastric plication (LGP) has gained increased acceptance as initial weight loss operation, but as with any other procedures, insufficient weight loss, early and late complications such as early and late strictures, gastroesophageal reflux and leak and others have been announced as an indication for revision to gastric bypass surgery as the correct solution. AIM: The aim of the study was to recognize the common indications for revision of gastric plication (GP) to RYGP and OAGB in our centers and to evaluate the outcome of treating weight regain, complications, and comorbidities. METHODS: A retrospective study conducted on 54 cases of undesirable results following gastric plication in other centers that were revised to gastric bypass procedures (RYGB and OAGB) from June 2015 to June 2018. Weight regain, gastroesophageal reflux disease not responding to medical treatment, undiagnosed hiatal hernia at surgery, post-operative leak, and strictures are the main categories included as indications for revision to gastric bypass in this study for a period of follow up to 2–5 years regarding weight loss, improvement of GERD and hiatal hernia, improvement of leak, stricture, and axial rotation of stomach. RESULTS: 54 consecutive patients included in this study previously subjected for LPG few years ago. 13 (24%) male and 41 (76%) female patients with mean age of 39.5 years ranging from (21–58) years and BMI from (41–48) Kg/m2. The main indication for revision surgery in the form of gastric bypass procedure (RYGB and OAGB) was weight regain in about 69% of cases. In addition to non-responding GERD to medical treatment (13%), hiatus hernia with plicated stomach migration to the mediastinum (3.7%), local collection secondary to leak (1.85%), stricture at site of plication (1.85%), and one case of axial rotation of the stomach (1.85%). Patient postoperatively done well and a follow-up for up to 3 years after revision surgery was uneventful. Most of our patients have good improvement regarding the inclusion criteria in our study (100% cured GERD, 90% cured leak site, about 90% cured symptomatic and radiological hiatal hernia, 100% cured after early, late strictures, and axial rotation while regarding loss of weight and least comorbidities about 88%). CONCLUSION: Although GP is an established bariatric procedure in treating and solving obesity and its complications, there are certain restrictions and difficulties that makes RYGB superior to GP.