[An update on gastroparesis in 2024]. / Le point sur la gastroparésie en 2024.

Gastroparesis is a pathology associating upper digestive symptoms, such as nausea and vomiting, with impaired gastric emptying in the absence of mechanical gastric or duodenal obstruction. It has a major impact on patients' quality of life, can lead to undernutrition, and -increases overall mortality. Several schools of thought converge on the hypothesis of a clinico--pathological spectrum of gastric neuro-muscular dysfunction encompassing gastroparesis and functional dyspepsia, in particular the subtype known as "postprandial distress syndrome". Its management includes non--pharmacological interventions, such as hygienic--dietary measures, pharmacological interventions using prokinetic, antiemetic or neuromodulatory treatments, and endoscopic interventions.

La gastroparésie est une pathologie associant des symptômes ­digestifs hauts, tels que des nausées et des vomissements, à un défaut de la vidange gastrique en l'absence d'une obstruction ­mécanique gastrique ou duodénale. Elle a un fort retentissement sur la qualité de vie des patients, peut amener à la dénutrition et augmente globalement la mortalité. Plusieurs courants de pensée convergent vers l'hypothèse d'un spectre clinicopathologique de dysfonction neuromusculaire gastrique englobant la gastroparésie et la dyspepsie fonctionnelle, notamment du sous-­type appelé « syndrome de détresse postprandiale ¼. Sa prise en charge ­comprend des interventions non pharmacologiques, telles que des mesures hygiénodiététiques, des interventions pharmacologiques à l'aide de traitements procinétiques, anti­émétiques ou encore neuromodulateurs, et des interventions ­endoscopiques.

Inuit population have shorter gastric emptying, higher duodenal motility and altered pan-enteric micromilieu: a comparative study between Greenlandic and Danish populations with and without type 2 diabetes.

Gastrointestinal function plays a pivotal role in nutrient absorption and overall digestive health. Abnormal gastric emptying is closely linked to type 2 diabetes, impacting blood glucose regulation and causing gastrointestinal symptoms. This study aims to investigate and compare segmental transit times, motility indices, and micromilieu between Greenlandic Inuit and Danish individuals with and without type 2 diabetes. We included forty-four Greenlandic Inuit, twenty-three of whom had type 2 diabetes, and age and gender-matched Danish individuals. Segmental transit time, motility, and luminal environment were measured using the SmartPill®. Greenlandic controls displayed shorter gastric emptying time (GET) (163 min), higher gastric median pH (2.0 pH) and duodenal median contractions (18.2 mm Hg) compared to Greenlanders with type 2 diabetes (GET: 235 min, pH:1.9, median duodenal contraction 18.4 mm Hg) and Danish controls (GET: 190, pH:1.2 median duodenal contraction 17.5 mmHg). Despite similar anti-diabetic management efforts, variations in gastrointestinal physiology were evident, highlighting the complexity of diabetes and its interaction with ethnicity, suggesting potential dietary or even genetic influences, emphasising the necessity for personalised diabetes management approaches. Finally, the study opens possibilities for future research, encouraging investigations into the underlying mechanisms linking genetics, diet, and gastric physiology, as an understanding of factors can lead to more effective, tailored strategies for diabetes care and improved digestive health in diverse populations.

Is it necessary to stop glucagon-like peptide-1 receptor agonists prior to endoscopic procedure? A retrospective study.

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1 RA) are effective in diabetes and obesity, reducing hyperglycemia by increasing insulin release and delaying gastric emptying. However, they can cause gastroparesis, raising concerns about aspiration during procedures. Recent guidelines advise discontinuing GLP-1 RA before surgery to reduce the risk of pulmonary aspiration. AIM: To evaluate the effect of GLP-1 RAs on gastric residual contents during endoscopic procedures. METHODS: A retrospective chart review at BronxCare Health System, New York, from January 2019 to October 2023, assessed gastric residue and aspiration in GLP-1 RA patients undergoing endoscopic procedures. Two groups were compared based on dietary status before the procedure. Data included demographics, symptoms of gastroparesis, opiate use, hemoglobin A1c, GLP-1 agonist indication, endoscopic details, and aspiration occurrence. IBM SPSS was used for analysis, calculating means, standard deviations, and applying Pearson's chi-square and t-tests for associations, with P < 0.05 as being significant. RESULTS: During the study, 306 patients were included, with 41.2% on a clear liquid/low residue diet and 58.8% on a regular diet before endoscopy. Most patients (63.1%) were male, with a mean age of 60 ± 12 years. The majority (85.6%) were on GLP-1 RAs for diabetes, and 10.1% reported digestive symptoms before endoscopy. Among those on a clear liquid diet, 1.5% had residual food at endoscopy compared to 10% on a regular diet, which was statistically significant (P = 0.03). Out of 31 patients with digestive symptoms, 13% had residual food, all from the regular diet group (P = 0.130). No complications were reported during or after the procedures. CONCLUSION: The study reflects a significant rise in GLP-1 RA use for diabetes and obesity. A 24-hour liquid diet seems safe for endoscopic procedures without aspiration. Patients with upper gastrointestinal symptoms might have a higher residual food risk, though not statistically significant. Further research is needed to assess risks based on diabetes duration, gastroparesis, and GLP-1 RA dosing, aiming to minimize interruptions in therapy during procedures.

Postoperative delayed gastric emptying: may gut microbiota play a role?

Postoperative delayed gastric emptying is a prevalent complication following surgical procedures, imposing heavy physical and financial burdens on patients. However, current treatment options remain suboptimal. In recent years, an increasing number of studies have highlighted that the gut microbiota and its metabolites are closely associated with postoperative complications. Various factors can disrupt the gut microbiome after surgery. This review discusses the potential mechanisms by which the gut microbiota and their metabolites may contribute to the pathogenesis of postoperative delayed gastric emptying. However, the current knowledge base is limited in terms of fully understanding the exact mechanisms involved. It is therefore evident that further research is required to fully elucidate the role of the gut microbiome in postoperative delayed gastric emptying, with the aim of uncovering new possibilities for preventive measures and therapeutic treatments.

Endoscopic pyloromyotomy for treatment of gastroparesis: A new standard or still an experimental approach?

Gastroparesis (GP) can be a severe and debilitating disease. Its pathophysiology is complex and not completely understood. Two principal mechanisms are responsible for the development of symptoms - gastric hypomotility and pylorospasm. Pylorus targeted therapies aim to decrease presumably elevated pyloric tone - pylorospasm. There is a growing body of evidence about their role in the treatment algorithm of GP. G-POEM (endoscopic pyloromyotomy) is an extensively studied pylorus targeted therapy. Its efficacy ranges between 56 and 80% and the number of recurrences among those with treatment effect seems low. G-POEM is a safe procedure with very low frequency of severe adverse events. At present, G-POEM should not be considered as an experimental approach and may be offered to all patients with refractory and severe GP. Nevertheless, G-POEM is not a first line treatment. Conservative measures such as diet modification and pharmacotherapy should always be tried before G-POEM is considered. Further research must focus on better patient selection as at present there are no standardized criteria. Functional imaging such as impedance planimetry (EndoFlip) may hold promise in this regard.

Impact of advanced age on the gastric emptying of water under fasted and fed state conditions.

Although older people are the main users of oral medications, few studies are reported on the influence of advanced age on gastric emptying rate of non-caloric liquids. This study aimed at evaluating the gastric emptying of 240 ml water in healthy older and young adults in fasted and fed state conditions using the established method of salivary caffeine kinetics. The gastric emptying of water was evaluated in 12 healthy older volunteers (mean age: 73 ± 6 years) and 12 healthy younger volunteers (mean age: 25 ± 2 years) with the ingestion of a rapid disintegrating tablet containing 20 mg of 13C3-caffeine. The gastric emptying of water was assessed indirectly by calculating the AUC ratios of salivary caffeine concentrations in specific time segments. Comparison of the AUC ratios showed no statistically significant difference between young and older volunteers in both fasted and fed state conditions (p > 0.05). Advanced age itself seems to have no relevant effect on gastric emptying of water in either fasted or fed state conditions and the phenomenon of Magenstrasse appears to follow a similar pattern in healthy older adults as in healthy younger adults.

A novel pilot study to evaluate the efficacy and safety of a wireless patch system in patients with chronic nausea and vomiting.

BACKGROUND: Gastric sensorimotor disorders (functional dyspepsia [FD] and gastroparesis [GP]) are prevalent and burdensome. Prolonged ambulatory recording using a wireless patch may provide novel information in these patients. METHODS: Consecutive adult patients (age ≥ 18 years) referred for gastric emptying scintigraphy (GES) were eligible for study inclusion. Patients were excluded if they had prior foregut surgery; were taking opioids or other medications known to affect gastric emptying; had a HgbA1C > 10; or were recently hospitalized. Three wireless motility patches were applied to the skin prior to GES. Patients wore the patches for 6 days while recording meals, symptoms, and bowel movements using an iPhone app. KEY RESULTS: Twenty-three consecutive adults (87% women; mean age = 43.9 years; mean BMI = 26.7 kg/m2) were enrolled. A gastric histogram revealed three levels of gastric myoelectric activity: weak, moderate, and strong. Patients with delayed gastric emptying at 4 h had weak gastric myoelectrical activity. Patients with nausea and vomiting had strong intestinal activity. Those with FD had weak gastric and intestinal myoelectric activity, and a weak meal response in the stomach, intestine, and colon compared to those with nausea alone or vomiting alone. CONCLUSIONS AND INFERENCES: Patients with FD, and those with delayed gastric emptying, had unique gastrointestinal myoelectrical activity patterns. Reduced postprandial pan-intestinal myoelectric activity may explain the symptoms of FD in some patients. Recording gastrointestinal activity over a prolonged period in the outpatient setting has the potential to identify unique pathophysiologic patterns and meal-related activity that distinguishes patients with distinct gastric sensorimotor disease states.

MoPill a novel gastrointestinal positioning system (GPS): New technology to navigate the alimentary tract highway.

BACKGROUND: Evaluation of gut motility in clinical practice is currently limited. A novel medical system (MoPill™) consisting of a capsule that wirelessly transmits radiofrequency signals to assess motility via 3D location, was used to conduct this study. The objectives were to: (1) confirm the safety of the MoPill™ system; (2) compare the 3D location transmitted by the capsule to its location captured by abdominal x-rays; 3 determine gastric emptying (GE), whole gut transit time (WGTT) and segmental transit times. METHODS: The MoPill™ system consists of an electronic capsule (2 × 1.2 cm), eight color-coded adhesive sensors (6 × 5.5 cm), a recorder (15 × 11 × 2 cm), and software on a laptop. Four sensors were applied to the abdomen and four to the back. Healthy subjects who had fasted overnight ingested a 250-calorie protein bar, 17 oz. of water, followed by an activated capsule. No further caloric contents were permitted for the next 5 h. At 1, 5, and 24 h (if the capsule had not been expelled), upright abdominal X-rays (AP and lateral) were obtained to assess the location of the capsule, which was compared to the gastrointestinal positioning system (GPS) location determined by the MoPill™ system. Identification of the capsule's anatomical location by the MoPill™ system was based on (1) the 3D (x, y, z) location; (2) time; (3) trajectory (e.g., going up the right side of the body signified ascending colon); (4) frequency of contractions (e.g., 3 cycles/min for the stomach); and (5) milestone relationship (e.g., pyloric passage must follow the end of gastric contractions). GE was determined first by the end of the 3 cycles/min rhythmic movement of the stomach and then again by pyloric expulsion on 3D location. Small intestine transit was taken as the duration from pyloric expulsion to arrival in the cecum. Colon transit time was determined by calculating the duration from 3D arrival in the cecum to passage of the capsule out of the body (i.e., loss of signal accompanying a bowel movement). KEY RESULTS: Ten healthy subjects (five women; mean age 34; mean BMI 24) were enrolled, and nine provided reliable data. The variation between the x-ray and the estimated (i.e., identified by the MoPill™ system) location of the capsule was within an average of 3.5 cm (range 0.9-9.4 cm). The mean GE was 3.1 h. The small intestine's mean transit time was 4.3 h. The mean colonic transit time was 17.6 h. There were no adverse events recorded during the study. CONCLUSIONS & INFERENCES: MoPill™ is a novel gastrointestinal positional system that accurately identifies the location of a capsule compared to an X-ray. MoPill™ system also recognizes GE, small bowel, colonic, and WGTT as well as segmental gut location and movement characteristics. MoPill™ offers the potential for new insights into GI motility disorders not attainable by current modalities.

Oral stimulation with glucose and fructose, but not sucrose, accelerates gastric emptying in humans.

Postprandial regulation of the gastric emptying (GE) rate plays an important role in food intake. Although oral sweetening with glucose may accelerate GE, the effects of different sweetness intensities of glucose (10% and 20%, w/v) and other energy sweeteners (e.g. fructose and sucrose) remain uncertain. The purpose of this study was to determine the effects of different glucose concentrations (Experiment 1) and different sugars with the same sweet taste intensity (Experiment 2) on postprandial GE. In both experiments, after ingesting a 200 kcal carbohydrate solution containing 50 g of maltodextrin, participants repeatedly sipped, but did not swallow, one of three (water, 10% and 20%, w/v glucose) or four (water and equally sweet 20%, w/v glucose, 12%, w/v fructose, and 14%, w/v sucrose) solutions for 1 min every 5 min over a 30 min period. GE was evaluated by measuring the temporal change in the cross-sectional area of the gastric antrum using ultrasound. In Experiment 1, oral stimulation with 20% (w/v) glucose resulted in greater GE than the control stimulus (i.e. water), but the effect of stimulation with 10% (w/v) glucose on GE was not different from that of the control stimulus. In Experiment 2, stimulation with 20% (w/v) glucose or 12% (w/v) fructose resulted in greater GE than the control stimulus. However, the effect of stimulation with 14% (w/v) sucrose on GE did not differ from that of the control stimulus. Consequently, oral stimulation with glucose or fructose solutions of moderate to high sweetness following a meal facilitates postprandial GE.

Effects of ondansetron on symptoms during a gastric emptying study and enteral lipid challenge and on daily symptoms in diabetic gastroenteropathy.

BACKGROUND: This study compared the effects of ondansetron and placebo in patients with diabetes mellitus and symptoms of dyspepsia (diabetic gastroenteropathy [DGE]). METHODS: We performed a randomized, double-blinded, placebo-controlled study of ondansetron tablets (8 mg) three times daily for 4 weeks in DGE patients. Symptoms were assessed with the Gastroparesis Cardinal Symptom Index daily diaries. Gastric emptying (GE) of solids (scintigraphy) and duodenal lipid infusions (300 kcal over 2 h) were each assessed twice, with placebo and ondansetron. Drug effects on GE, symptoms during the GE study and during lipid infusion, and daily symptoms were analyzed. KEY RESULTS: Of 41 patients, 37 completed both GE studies and one completed 1; 31 completed both lipid infusions and four only placebo; and all 35 randomized patients completed 4 weeks of treatment. Compared to placebo, ondansetron reduced the severity of fullness (p = 0.02) and belching (p = 0.049) during lipid infusion but did not affect GE T1/2. Both ondansetron and placebo improved daily symptoms versus the baseline period (p < 0.05), but the differences were not significant. In the analysis of covariance of daily symptoms during the treatment period, the interaction term between treatment and the acute effect of ondansetron on symptoms during lipid challenge was significant (p = .024). CONCLUSIONS & INFERENCES: Ondansetron significantly reduced fullness during enteral lipid infusion in patients with DGE. Overall, ondansetron did not improve daily symptoms versus placebo. But patients in whom ondansetron improved symptoms during enteral lipid challenge were perhaps more likely to experience symptom relief during daily treatment.

Effect of sex on chronic stress induced alterations in hindbrain catecholaminergic system and autonomic dysfunction resulting in gastrointestinal dysmotility.

It has been reported that the clinical symptoms of functional dyspepsia (FD) exacerbate upon stress while the gender-related factors have been incompletely understood. This study aims to investigate the role of sex in chronic heterotypic stress (CHS)-induced autonomic and gastric motor dysfunction. For CHS, the rats were exposed to the combination of different stressors for 7 consecutive days. Subsequently, electrocardiography was recorded in anesthetized rats to evaluate heart rate variability (HRV) for the determination of autonomic outflow and sympathovagal balance. Solid gastric emptying (GE) was measured in control and CHS-loaded male and female rats. The immunoreactivities of catecholaminergic cell marker tyrosine hydroxylase (TH), choline acetyltransferase (ChAT), corticotropin releasing factor (CRF), and estrogen receptor (ER-α/ß) were evaluated in medullary and pontine brainstem sections by immunohistochemistry. Compared with the controls, CHS significantly delayed GE in males but not in females. There was no significant sex-related difference in parasympathetic indicator HF under either control or CHS conditions. Sympathetic indicator LF was significantly higher in control females compared to the males. The higher sympathetic output in females was found to be attenuated upon CHS; in contrast, the elevated sympathetic output was detected in CHS-loaded males. No sex- or stress-related effect was observed on ChAT immunoreactivity in the dorsal motor nucleus of N.vagus (DMV). In males, greater number of TH-ir cells was observed in the caudal locus coeruleus (LC), while they were more densely detected in the rostral LC of females. Regardless of sex, CHS elevated immunoreactivity of TH throughout the LC. Under basal conditions, greater number of TH-ir cells was detected in the rostral ventrolateral medulla (RVLM) of females. In contrast, CHS remarkably increased the number of TH-ir cells in the RVLM of males which was found to be decreased in females. There was no sex-related alteration in TH immunoreactivity in the nucleus tractus solitarius (NTS) of control rats, while CHS affected both sexes in a similar manner. Compared with females, CRF immunoreactivity was prominently observed in control males, while both of which were stimulated by CHS. ER-α/ß was found to be co-expressed with TH in the NTS and LC which exhibit no alteration related to either sex or stress status. These results indicate a sexual dimorphism in the catecholaminergic and the CRF system in brainstem which might be involved in the CHS-induced autonomic and visceral dysfunction occurred in males.

The role of diet in diabetes gastroparesis treatment: a systematic review and meta-analysis.

Background: Diabetic gastroparesis is a common complication in patient with diabetes. Dietary intervention has been widely used in the treatment of diabetic gastroparesis. The aim of this study is to evaluate the role of diet in the treatment of diabetic gastroparesis. Methods: This systematic review was conducted a comprehensive search of randomized controlled trials using dietary interventions for the treatment of diabetic gastroparesis up to 9 November 2023. The primary outcomes were gastric emptying time and clinical effect, while fasting blood glucose, 2-hour postprandial blood glucose and glycosylated hemoglobin were secondary outcomes. Data analysis was performed using RevMan 5.4 software, and publication bias test was performed using Stata 15.1 software. Results: A total of 15 randomized controlled trials involving 1106 participants were included in this review. The results showed that patients with diabetic gastroparesis benefit from dietary interventions (whether personalized dietary care alone or personalized dietary care+routine dietary care). Compared with routine dietary care, personalized dietary care and personalized dietary care+routine dietary care can shorten the gastric emptying time, improve clinical efficacy, and reduce the level of fasting blood glucose, 2-hour postprandial blood glucose and glycosylated hemoglobin. Conclusions: Limited evidence suggests that dietary intervention can promote gastric emptying and stabilize blood glucose control in patients with diabetic gastroparesis. Dietary intervention has unique potential in the treatment of diabetic gastroparesis, and more high-quality randomized controlled trials are needed to further validate our research results. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023481621.

Nandrolone decanoate impairs gastrointestinal motility and duodenal morphometry in moderately exercised rats.

The misuse of anabolic androgenic steroid associated or not with physical workouts disrupts gastrointestinal (GI) function homeostasis. Our goal was to investigate the effects of nandrolone decanoate (ND) and moderate swimming on the GI transit of solid meals, GI motor contractility, and intestinal histology in rats. Male Wistar rats were allocated to four groups that received intramuscular injections of ND (5.0 mg/kg) or vehicle (60.0 µL) and were submitted or not to swimming sessions (60 min, 5% body weight overload) for 4 weeks. Gastric emptying, intestinal transit, in vitro GI contractility, intestinal morphometry, and duodenal mucosal mast cells were evaluated in all experimental groups. ND treatment accelerated gastric emptying, slowed small intestine transit time, enhanced gastric carbachol-mediated reactivity, decreased crypt depth and villus height, reduced mucosal thickness, and increased the circular and longitudinal muscle layer thickness of the duodenum in sedentary rats. Moderate exercise accelerated intestinal transit time and reduced submucosa thickness. In vehicle-treated animals, a strong negative correlation was found between intestinal transit and mucosal mast cells, which was reversed by ND treatment. Combining ND treatment and swimming accelerated gastric emptying, increased duodenal cholinergic reactivity, inhibited the sodium nitroprusside relaxing response, increased the number of duodenal mast cells, decreased villus height, and increased the thickness of all muscle layers. ND changed the morphological and functional properties of the GI tract over time, with intense dysmotility, especially in sedentary animals, but moderate exercise seemed to have played a compensatory role in these harmful effects in the gut.

Evaluation of the Effect of Thickeners in Enteral Formulas on the Gastric Emptying Rate of Proteins and Carbohydrates Using a Semi-Dynamic Gastric Model.

The emptying rate of specific nutrients in enteral formulas is poorly understood, despite the importance of controlling the emptying rate in tube-fed patients. Because of their viscosity, thickened formulas are widely used to avoid gastric reflux and reduce the burden on caregivers. This study examined how thickeners in enteral formulas affected the gastric emptying rates of proteins and carbohydrates. A semi-dynamic gastric model was used to prepare and digest test enteral formulas that contained either no thickeners or agar (0.2%). The amounts of protein and carbohydrates in each emptied aliquot were determined, and the emptying rate was calculated. We found that agar accelerated protein emptying, and an exploratory experiment with agar (0.5%) suggested the possibility of concentration dependence. Additionally, experiments using gellan gum (0.08%), guar gum (0.2%), or carrageenan (0.08%, 0.2%) suggested that protein emptying could vary depending on the thickener type and that carrageenan might slow it. These results could help with the appropriate selection of thickeners added to liquid foods based on the patient's metabolic profile to manage nutrition, not only for tube-fed patients but also for those with oropharyngeal dysphagia or diabetes.

Low Vitamin D Levels in Patients with Symptoms of Gastroparesis: Relationships with Nausea and Vomiting, Gastric Emptying and Gastric Myoelectrical Activity.

Patients with gastroparesis (Gp) often have diets deficient in calories, electrolytes, and vitamins. Vitamin D levels have been reported to be low in some patients with Gp but has not been systematically studied. AIMS: To determine vitamin D levels and relationships among symptoms, gastric emptying and gastric myoelectrical activity (GMA) in patients with symptoms of Gp. METHODS: 25-hydroxy-vitamin D was measured in patients at enrollment in the Gastroparesis Clinical Consortium Registry. Gastroparesis Cardinal Symptoms Index (GCSI), gastric emptying, and GMA before and after water load satiety test (WLST) were measured. GMA, expressed as percentage distribution of activity in normal and dysrhythmic ranges, was recorded using electrogastrography. RESULTS: Overall, vitamin D levels were low (< 30 ng/ml) in 288 of 513 (56.1%) patients with symptoms of Gp (206 of 376 (54.8%) patients with delayed gastric emptying (Gp) and 82 of 137 (59.9%) patients with symptoms of Gp and normal gastric emptying). Low vitamin D levels were associated with increased nausea and vomiting (P < 0.0001), but not with fullness or bloating subscores. Low vitamin D levels in patients with Gp were associated with greater meal retention at four hours (36% retention) compared with Gp patients with normal vitamin D levels (31% retention; P = 0.05). Low vitamin D in patients with normal gastric emptying was associated with decreased normal 3 cpm GMA before (P = 0.001) and increased tachygastria after WLST (P = 0.01). CONCLUSIONS: Low vitamin D levels are present in half the patients with symptoms of gastroparesis and are associated with nausea and vomiting and gastric neuromuscular dysfunction.

Effect of lixisenatide on liquid gastric emptying in type 2 diabetes - Implications for the use of GLP-1 receptor agonists before procedures.

Gastric emptying of a glucose drink was measured in people with type 2 diabetes given lixisenatide (20 µg/day or placebo) for 8 weeks. Intragastric retention at 240 min (2 (0-11)% vs 48 (3-97)%; P < 0.0001) was much greater with lixisenatide than placebo. Accordingly, lixisenatide may delay liquid gastric emptying markedly.

Surface mapping of gastric motor functions using MRI: a comparative study between humans and rats.

The stomach's ability to store, mix, propel, and empty its content requires highly coordinated motor functions. However, current diagnostic tools cannot simultaneously assess these motor processes. This study aimed to use magnetic resonance imaging (MRI) to map multifaceted gastric motor functions, including accommodation, tonic and peristaltic contractions, and emptying, through a single noninvasive experiment for both humans and rats. Ten humans and 10 Sprague-Dawley rats consumed MRI-visible semisolid meals and underwent MRI scans. We used a surface model to analyze MRI data, capturing the deformation of the stomach wall on ingestion or during digestion. We inferred muscle activity, mapped motor processes, parcellated the stomach into functional regions, and revealed cross-species distinctions. In humans, both the fundus and antrum distended postmeal, followed by sustained tonic contractions to regulate intragastric pressure. Peristaltic contractions initiated from the distal fundus, including three concurrent wavefronts oscillating at 3.3 cycles/min and traveling at 1.7 to 2.9 mm/s. These motor functions facilitated linear gastric emptying with a 61-min half-time. In contrast, rats exhibited peristalsis from the midcorpus, showing two wavefronts oscillating at 5.0 cycles/min and traveling at 0.4 to 0.9 mm/s. For both species, motility features allowed functional parcellation of the stomach along a midcorpus division. This study maps region- and species-specific gastric motor functions. We demonstrate the value of MRI with surface modeling in understanding gastric physiology and its potential to become a new standard for clinical and preclinical investigations of gastric disorders at both individual and group levels.NEW & NOTEWORTHY A novel MRI technique can visualize how the stomach accommodates, mixes, and propels food for digestion in humans and animals alike. Digital models of gastric MRI reveal the functional maps, organization, and distinction of the stomach across individuals and species. This technique holds the unique potential to advance basic and clinical studies of functional gastric disorders.

The effect of pre-operative biliary drainage in resectable periampullary lesions: a systematic review and meta-analysis.

OBJECTIVE: The effect of a pre-operative biliary stent on complications after pancreaticoduodenectomy (PD) remains controversial. MATERIALS AND METHOD: We conducted a meta-analysis according to the preferred reporting items for systematic reviews and meta-analyses guidelines, and PubMed, Web of Science Knowledge, and Ovid's databases were searched by the end of February 2023. 35 retrospective studies and 2 randomized controlled trials with a total of 12641 patients were included. RESULTS: The overall complication rate of the pre-operative biliary drainage (PBD) group was significantly higher than the no-PBD group (odds ratio [OR] 1.46, 95% confidence interval [CI] 1.22-1.74; p < 0.0001), the incidence of post-operative delayed gastric emptying was increased in patients with PBD compared those with early surgery (OR 1.21, 95% CI: 1.02-1.43; p = 0.03), and there was a significant increase in post-operative wound infections in patients receiving PBD with an OR of 2.2 (95% CI: 1.76-2.76; p < 0.00001). CONCLUSIONS: PBD has no beneficial effect on post-operative outcomes. The increase in post-operative overall complications and wound infections urges the exact indications for PBD and against routine pre-operative biliary decompression, especially for patients with total bilirubin < 250 umol/L waiting for PD.

OBJETIVO: El efecto de una endoprótesis biliar pre-operatoria sobre las complicaciones después de la pancreaticoduodenectomía sigue siendo controvertido. MATERIALES Y MÉTODO: Se llevó a cabo un metaanálisis siguiendo las directrices PRISMA y se realizaron búsquedas en PubMed, Web of Science Knowledge y la base de datos de Ovid hasta finales de febrero de 2023. Se incluyeron 35 estudios retrospectivos y 2 ensayos controlados aleatorizados, con un total de 12,641 pacientes. RESULTADOS: La tasa global de complicaciones del grupo drenaje biliar pre-operatorio (PBD) fue significativamente mayor que la del grupo no-PBD (odds ratio [OR]: 1.46; intervalo de confianza del 95% [IC 95%]: 1.22-1.74; p < 0.0001), la incidencia de vaciado gástrico retardado posoperatorio fue mayor en los pacientes con PBD en comparación con los de cirugía precoz (OR: 1.21; IC95%: 1.02-1.43; p = 0.03), y hubo un aumento significativo de las infecciones posoperatorias de la herida en los pacientes que recibieron PBD (OR: 2.2; IC 95%: 1.76-2.76; p < 0.00001). CONCLUSIONES: El drenaje biliar pre-operatorio no tiene ningún efecto beneficioso sobre el resultado posoperatorio. El aumento de las complicaciones posoperatorias globales y de las infecciones de la herida urge a precisar las indicaciones de PBD y a desaconsejar la descompresión biliar pre-operatoria sistemática, en especial en pacientes con bilirrubina total inferior a 250 µmol/l en espera de pancreaticoduodenectomía.

Aggregation structure induced by heat treatments mediated the gastric digestion behavior of soybean protein.

The common belief that heat treatment enhances the gastric digestion of proteins is largely based on findings from animal proteins and may not apply to all proteins, particularly plant proteins. Here, we compared the digestion characteristics of soybean protein isolates (SPI) in an in vitro semi-dynamic digestion model and found distinct effects of heat treatment on the digestion properties of plant proteins. The results revealed that heat-treated SPIs formed clots during the early stages of digestion, although the clots gradually became smaller and looser as digestion progressed, the systems remained turbid at the end of gastric digestion, indicating the lag in their emptying. Furthermore, heat treatment altered the rheological properties of SPI, resulting in increased viscosity and slower gastric emptying. These effects became more pronounced with increasing heat treatment temperatures. The fluorescence spectrum analysis indicated that heat treatment altered its conformation. This led to protein unfolding and exposure of hydrophobic groups, facilitating the formation of larger aggregates during digestion. Additionally, heat treatment exposed more cleavage sites for gastric proteases, increasing the extent of hydrolysis. Elevated levels of free amino acids and a smaller molecular weight distribution further corroborated these findings. These findings contribute to a deeper understanding of the gastric digestion characteristics of plant proteins and the relationship between protein aggregation structure and the digestion process.