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1.
Asian J Endosc Surg ; 17(4): e13392, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39379049

ABSTRACT

PURPOSE: We investigated the relationship between the resected stomach measurements, the incidence of delayed gastric emptying (DGE), and food residue 1 year after surgery in patients who underwent laparoscopic pylorus-preserving gastrectomy (PPG). MATERIALS AND METHODS: The DGE group included 10 patients fasting due to nausea, vomiting, abdominal distension, or remnant stomach distension on radiographs; the control group included 36 patients without these symptoms. We compared the size and length of lesser and greater curvatures of the resected stomach and endoscopic findings after 1 year. RESULTS: No significant differences were observed between groups in terms of sex, body mass index, gross type, histology, tumor progression, number of dissected lymph nodes, operating time, or blood loss. The DGE group was older, had a longer postoperative stay, and showed a smaller size and shorter greater curvature of the resected stomach than the control group (p < 0.01 for all). No difference was observed in the length of the lesser curvature of the resected stomach. In addition, there were no disparities in residual food, degree and extent of gastritis, or bile reflux 1 year after gastrectomy. CONCLUSIONS: Measurements of the resected stomach suggest that preventing DGE may be achievable by removing a larger area of the greater curvature and/or stomach during laparoscopic PPG. This implies potential surgical strategy improvements for better outcomes. Further multicenter trials are needed to validate and refine techniques.


Subject(s)
Gastrectomy , Gastric Emptying , Laparoscopy , Pylorus , Stomach Neoplasms , Humans , Gastrectomy/methods , Female , Male , Laparoscopy/methods , Middle Aged , Aged , Gastric Emptying/physiology , Stomach Neoplasms/surgery , Pylorus/surgery , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Retrospective Studies , Adult , Organ Sparing Treatments/methods
2.
Elife ; 132024 Oct 15.
Article in English | MEDLINE | ID: mdl-39404608

ABSTRACT

Motor systems operate over a range of frequencies and relative timing (phase). We studied the role of the hyperpolarization-activated inward current (Ih) in regulating these features in the pyloric rhythm of the stomatogastric ganglion (STG) of the crab, Cancer borealis, as temperature was altered from 11°C to 21°C. Under control conditions, rhythm frequency increased monotonically with temperature, while the phases of the pyloric dilator (PD), lateral pyloric (LP), and pyloric (PY) neurons remained constant. Blocking Ih with cesium (Cs+) phase advanced PD offset, LP onset, and LP offset at 11°C, and the latter two further advanced as temperature increased. In Cs+ the frequency increase with temperature diminished and the Q10 of the frequency dropped from ~1.75 to ~1.35. Unexpectedly in Cs+, the frequency dynamics became non-monotonic during temperature transitions; frequency initially dropped as temperature increased, then rose once temperature stabilized, creating a characteristic 'jag'. Interestingly, these jags persisted during temperature transitions in Cs+ when the pacemaker was isolated by picrotoxin, although the temperature-induced change in frequency recovered to control levels. Overall, these data suggest that Ih plays an important role in maintaining smooth transitory responses and persistent frequency increases by different mechanisms in the pyloric circuitry during temperature fluctuations.


Subject(s)
Brachyura , Temperature , Animals , Brachyura/physiology , Pylorus/physiology , Ganglia, Invertebrate/physiology , Neurons/physiology
4.
Am J Case Rep ; 25: e944624, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39238181

ABSTRACT

BACKGROUND The pediatric population, due to its distinct anatomy and physiology, often presents with unique mechanisms of trauma, leading clinicians to encounter diverse and sometimes unexpected injuries. Whether these injuries result from blunt or penetrating trauma, they may involve intra-abdominal organs in pediatric patients. Additionally, there are occasional occurrences where injuries affect rare sites such as the pylorus in an isolated manner within this age group. Clinicians must be prepared to address a wide range of injury patterns to ensure optimal outcomes for pediatric patients experiencing trauma to intra-abdominal structures such as the pylorus. CASE REPORT We report a 19-month-old boy who presented with abdominal pain, crying, and repeated vomiting of gastric contents after a wardrobe fell on his upper torso. His vital signs were stable except that he was tachycardiac. Upon investigation, abdominal computed tomography (CT) revealed pneumoperitoneum, free peritoneal fluid, and inflammatory changes in the intestinal wall, suggesting hollow viscus injury. Exploratory laparotomy was performed, and complete transection of the pyloric area of the stomach was identified. The pancreatic and biliary ducts were intact. On postoperative day 5, an upper gastrointestinal (UGI) contrast study prior to initiating oral feeding was done and showed normal findings with no contrast leakage. His postoperative course was unremarkable. CONCLUSIONS Isolated pyloric injuries following blunt trauma are rare with no known case reports in pediatric age group. High morbidity and mortality rates can result from traumatic gastrointestinal injuries including the involvement of pylorus. Therefore, accurate diagnosis and prompt management are essential for an improved outcome.


Subject(s)
Abdominal Injuries , Pylorus , Wounds, Nonpenetrating , Humans , Male , Wounds, Nonpenetrating/complications , Pylorus/injuries , Infant , Abdominal Injuries/complications , Tomography, X-Ray Computed , Laparotomy
5.
Scand J Gastroenterol ; 59(10): 1159-1165, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39189721

ABSTRACT

BACKGROUND/AIMS: During esophagectomy for malignancy, the anterior and posterior branches of the vagus nerve are transected in order to achieve surgical radicality. This leads to loss of central nervous system-control of the pylorus which may lead to delayed gastric emptying. We aimed to investigate the feasibility of the EndoFLIP technique for assessment of pyloric biomechanical properties in patients undergoing esophagectomy. METHODS: A feasibility study in six patients undergoing surgery was conducted. EndoFLIP measurements were carried out preoperative (Pre-op), after surgical resection (Post-op) and following prophylactic balloon dilatation of the pylorus (Post-dil). By measuring the cross-sectional area and pressure of the pylorus the pyloric compliance and the incremental pressure-strain elastic modulus (Ep) were calculated. RESULTS: Placing the catheter in the pyloric region was successfully achieved in all six patients. No complications were observed. Resection of the esophagus increased the incremental pyloric elastic modulus (Ep) from 0.59 ± 0.18 kPa to 0.99 ± 0.34 kPa (p = 0.03). After dilatation, the Ep was reduced to 0.53 ± 0.23 kPa (p = 0.04), which was close to Pre-op (p = 0.62). The pyloric compliance showed a similar pattern as that found for Ep. CONCLUSION: The EndoFLIP system holds promise for assessment of biomechanics of the pyloric region in patients undergoing esophagectomy for cancer.


Subject(s)
Esophageal Neoplasms , Esophagectomy , Feasibility Studies , Pylorus , Humans , Esophagectomy/adverse effects , Esophagectomy/methods , Pylorus/surgery , Male , Middle Aged , Aged , Esophageal Neoplasms/surgery , Female , Elastic Modulus , Gastric Emptying , Vagus Nerve
6.
eNeuro ; 11(9)2024 Sep.
Article in English | MEDLINE | ID: mdl-39134416

ABSTRACT

Ionic current levels of identified neurons vary substantially across individual animals. Yet, under similar conditions, neural circuit output can be remarkably similar, as evidenced in many motor systems. All neural circuits are influenced by multiple neuromodulators, which provide flexibility to their output. These neuromodulators often overlap in their actions by modulating the same channel type or synapse, yet have neuron-specific actions resulting from distinct receptor expression. Because of this different receptor expression pattern, in the presence of multiple convergent neuromodulators, a common downstream target would be activated more uniformly in circuit neurons across individuals. We therefore propose that a baseline tonic (non-saturating) level of comodulation by convergent neuromodulators can reduce interindividual variability of circuit output. We tested this hypothesis in the pyloric circuit of the crab, Cancer borealis Multiple excitatory neuropeptides converge to activate the same voltage-gated current in this circuit, but different subsets of pyloric neurons have receptors for each peptide. We quantified the interindividual variability of the unmodulated pyloric circuit output by measuring the activity phases, cycle frequency, and intraburst spike number and frequency. We then examined the variability in the presence of different combinations and concentrations of three neuropeptides. We found that at mid-level concentration (30 nM) but not at near-threshold (1 nM) or saturating (1 µM) concentrations, comodulation by multiple neuropeptides reduced the circuit output variability. Notably, the interindividual variability of response properties of an isolated neuron was not reduced by comodulation, suggesting that the reduction of output variability may emerge as a network effect.


Subject(s)
Brachyura , Neurons , Neuropeptides , Animals , Brachyura/physiology , Neuropeptides/metabolism , Neurons/physiology , Male , Ganglia, Invertebrate/physiology , Action Potentials/physiology , Pylorus/physiology
7.
Surg Endosc ; 38(10): 6046-6052, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39134721

ABSTRACT

BACKGROUND: Delayed gastric emptying (DGE) is a common complication after esophagectomy. BOTOX injections and pyloric surgeries (PS), including pyloroplasty (PP) and pyloromyotomy (PM), are performed intraoperatively as prophylaxis against DGE. This study compares the effects of pyloric BOTOX injection and PS for preventing DGE post-esophagectomy. METHODS: We retrospectively reviewed Moffitt's IRB-approved database of 1364 esophagectomies, identifying 475 patients receiving BOTOX or PS during esophageal resection. PS was further divided into PP and PM. Demographics, clinical characteristics, and postoperative outcomes were compared using Chi-Square, Fisher's exact test, Wilcoxon rank-sum, and ANOVA. Propensity-score matching was performed between BOTOX and PP cohorts. RESULTS: 238 patients received BOTOX, 108 received PP, and 129 received PM. Most BOTOX patients underwent fully minimally invasive robotic Ivor-Lewis esophagectomy (81.1% vs 1.7%) while most PS patients underwent hybrid open/Robotic Ivor-Lewis esophagectomy (95.7% vs 13.0%). Anastomotic leak (p = 0.57) and pneumonia (p = 0.75) were comparable between groups. However, PS experienced lower DGE rates (15.9% vs 9.3%; p = 0.04) while BOTOX patients had less postoperative weight loss (9.7 vs 11.45 kg; p = 0.02). After separating PP from PM, leak (p = 0.72) and pneumonia (p = 0.07) rates remained similar. However, PP patients had the lowest DGE incidence (1.9% vs 15.7% vs 15.9%; p = < 0.001) and the highest bile reflux rates (2.8% vs 0% vs 0.4%; p = 0.04). Between matched cohorts of 91 patients, PP had lower DGE rates (18.7% vs 1.1%; p = < 0.001) and less weight loss (9.8 vs 11.4 kg; p = < 0.001). Other complications were comparable (all p > 0.05). BOTOX was consistently associated with shorter LOS compared to PS (all p = < 0.001). CONCLUSION: PP demonstrates lower rates of DGE in unmatched and matched analyses. Compared to BOTOX, PS is linked to reduced DGE rates. While BOTOX is associated with more favorable LOS, this may be attributable to difference in operative approach. PP improves DGE rates after esophagectomy without improving other postoperative complications.


Subject(s)
Botulinum Toxins, Type A , Esophagectomy , Postoperative Complications , Pylorus , Humans , Esophagectomy/adverse effects , Esophagectomy/methods , Female , Male , Retrospective Studies , Middle Aged , Pylorus/surgery , Botulinum Toxins, Type A/administration & dosage , Postoperative Complications/prevention & control , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Gastroparesis/prevention & control , Gastroparesis/etiology , Aged , Intraoperative Care/methods , Pyloromyotomy/methods , Gastric Emptying/drug effects , Propensity Score , Injections , Anastomotic Leak/prevention & control , Anastomotic Leak/etiology , Anastomotic Leak/epidemiology
8.
J Med Case Rep ; 18(1): 397, 2024 Aug 24.
Article in English | MEDLINE | ID: mdl-39180137

ABSTRACT

BACKGROUND: Gastric adenomyoma is a rare benign tumor composed of glandular structures and smooth muscle fibers. While some classify gastric adenomyoma as a hamartoma, others view it as an abortive form of heterotopic pancreas. Despite its benign nature, there is a risk of malignant transformation. Predominantly found in the antrum, gastric adenomyoma affects all ages but is most common in adults aged 40-60 years. Symptoms are nonspecific, and its similarity to other lesions complicates diagnosis. This paper aims to provide a review of medical literature on gastric adenomyoma and its diagnosis and treatment methods, along with presenting an additional case report on the same topic. CASE PRESENTATION: We present the case of a 55-year-old Syrian man who experienced vomiting, weight loss, and chronic partial constipation. An obstructing mass in the pylorus was detected, and then an open surgery was performed to excise the lesion. A biopsy of the resected mass was obtained for histopathological examination. The final diagnosis of the lesion was pyloric-region adenomyoma with severe pyloric stenosis. After the successful surgery, the patient recovered without any recurrence or complications. CONCLUSIONS: Several diagnostic approaches are available, including radiological studies, endoscopic examination, and fine needle aspiration guided by endoscopic ultrasonography. Treatment options involve endoscopic submucosal dissection and complete laparotomy resection. Further studies and thorough reviews are recommended to better understand the best clinical practices. Practitioners should consider gastric adenomyoma when encountering a mural gastric lesion.


Subject(s)
Adenomyoma , Gastric Outlet Obstruction , Stomach Neoplasms , Humans , Male , Middle Aged , Adenomyoma/pathology , Adenomyoma/surgery , Adenomyoma/complications , Adenomyoma/diagnostic imaging , Gastric Outlet Obstruction/etiology , Gastric Outlet Obstruction/surgery , Stomach Neoplasms/complications , Stomach Neoplasms/pathology , Stomach Neoplasms/diagnosis , Stomach Neoplasms/surgery , Pylorus/pathology , Pylorus/surgery , Vomiting/etiology , Treatment Outcome
9.
Pathol Oncol Res ; 30: 1611823, 2024.
Article in English | MEDLINE | ID: mdl-39165646

ABSTRACT

Objective: The topic of this meta-analysis is the comparison of gastric conduit esophageal reconstructions with or without pyloroplasty. Background: Surgical procedures, especially minimal invasive esophagectomy (MIE) can be a curative treatment in the early stages of esophageal cancer. Previously, intraoperative pyloroplasty was routinely performed, but nowadays it became debated again in the light of minimally invasive esophagectomy. Methods: A comprehensive search was performed in multiple databases to identify randomized controlled trials investigating the topic. Two independent authors performed the selection based on predefined criteria. Statistical analysis was performed to assess any significant difference, then the bias and quality of the data were estimated. Results: Nine relevant RCTs consisting of 529 patients with esophageal cancer were identified. No significance was found in mortality [odds ratio (OR): 0.85; p = 0.642], anastomosis leakage (OR: 0.57; p = 0.254), respiratory morbidity (OR: 0.51; p = 0.214) and vomiting (OR: 0.74; p = 0.520), however the results about gastric emptying time (GET) were controversial (weighted mean difference (WMD): -67.71; p = 0.009, OR: 2.75; p = 0.072). Significant heterogeneity was not detected except for GET. Trial sequential analyses (TSA) show that a certain conclusion would require more data except in the binary variables of GET. Conclusion: We conclude that the pyloric drainage procedure is not routinely necessary, but further well-designed studies would be needed, especially in Europe.


Subject(s)
Drainage , Esophageal Neoplasms , Esophagectomy , Randomized Controlled Trials as Topic , Humans , Esophagectomy/methods , Esophageal Neoplasms/surgery , Drainage/methods , Pylorus/surgery
10.
Best Pract Res Clin Gastroenterol ; 71: 101910, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39209413

ABSTRACT

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.


Subject(s)
Gastroparesis , Pyloromyotomy , Pylorus , Gastroparesis/surgery , Gastroparesis/physiopathology , Gastroparesis/therapy , Gastroparesis/etiology , Humans , Pyloromyotomy/methods , Pyloromyotomy/adverse effects , Treatment Outcome , Pylorus/surgery , Pylorus/physiopathology , Gastric Emptying , Patient Selection , Recurrence
11.
Scand J Gastroenterol ; 59(9): 1035-1038, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39105565

ABSTRACT

OBJECTIVES: Gastroparesis that is refractory to standard dietary and medical management may benefit from surgical treatment with gastric electrical neurostimulation, which has shown promise in reducing symptoms of the disease. Pyloroplasty may serve an adjunctive role to a gastric stimulator, but the precise benefit remains unclear. The present study compares reported rates of symptom improvement following gastric neurostimulator implantation with and without pyloroplasty. MATERIALS AND METHODS: A single center retrospective analysis of consecutive patients who received operative management for symptom refractory gastroparesis from 1 January 2020 to 31 December 2021 was performed. Subjects were assigned to cohorts based on treatment with gastric electrical stimulation alone (GES-only) or combined with pyloroplasty (GES + PP). A survey-based assessment was administered post-operatively that evaluated cardinal symptoms of gastroparesis (nausea, vomiting, early satiety) before and after treatment. RESULTS: In total, 42 patients (15 GES-only, 27 GES + PP) were included in the study. Both groups reported a high degree of improvement in global symptom control following surgery (93% vs 81%) with no differences between treatment cohorts (p = 0.09). Early satiety demonstrated better improvement in patients who received gastric stimulation alone (p = 0.012). Subgroup analysis of diabetic gastroparesis patients showed a 2.2% decrease in hemoglobin A1c levels in the GES + PP group (p-0.034). CONCLUSIONS: Symptom reduction in refractory gastroparesis appears to improve after placement of a gastric neurostimulator with or without the addition of a pyloroplasty procedure.


Subject(s)
Electric Stimulation Therapy , Gastroparesis , Humans , Gastroparesis/therapy , Gastroparesis/etiology , Retrospective Studies , Female , Male , Middle Aged , Electric Stimulation Therapy/methods , Adult , Pylorus/surgery , Treatment Outcome , Aged , Blood Glucose/metabolism , Blood Glucose/analysis , Combined Modality Therapy
13.
BMJ Case Rep ; 17(7)2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39074943

ABSTRACT

A term male baby was born vaginally to a primi mother. An antenatal ultrasound revealed polyhydramnios and a distended stomach in the baby. At birth, the baby had well-defined areas of peeling skin on the face and blisters on the forearm region. The abdominal X-ray revealed a single gastric bubble, which is consistent with pyloric atresia and needs surgery. Pyloroplasty was initially performed, but it was unsuccessful. Therefore, a feeding jejunostomy and gastrostomy were performed. However, the baby developed sepsis and septic shock and died at about 2 months of age. Skin biopsy revealed cleavage above the lamina densa, and genetic analysis indicated heterozygosity in ITGB4 exons 10 and 16, which are associated with epidermolysis bullosa junctionalis and pyloric atresia.


Subject(s)
Pylorus , Humans , Infant, Newborn , Male , Pylorus/abnormalities , Pylorus/pathology , Fatal Outcome , Epidermolysis Bullosa, Junctional/genetics , Epidermolysis Bullosa, Junctional/pathology , Epidermolysis Bullosa, Junctional/complications , Gastric Outlet Obstruction/etiology , Gastric Outlet Obstruction/surgery , Integrin beta4/genetics
14.
Adv Neonatal Care ; 24(4): 374-381, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38986126

ABSTRACT

BACKGROUND: Enteral feeding by a transpyloric tube in critically ill infants is indicated when there is a failure in gastric feeding. However, there is a wide variability regarding the insertion technique. PURPOSE: To perform a systematic review of the methods for inserting a transpyloric feeding tube in newborns and infants. DATA SOURCES: Nine databases, without date or language restrictions, accessed in September 2021. STUDY SELECTION: A systematic review of experimental and nonexperimental studies, according to the "Patient/problem; Intervention; Comparison; Outcome" strategy and the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" guidelines. The clinical question was about the measurement and insertion techniques, as well as the success rates of properly placing a transpyloric tube in newborns and infants. DATA EXTRACTION: Two authors (N.M.Q. and J.F.S.) analyzed 6 observational descriptive prospective studies, all of them published in peer-reviewed indexed medical journals and one in the official journal of the National Association of Neonatal Nurses. RESULTS: The success rate varied between 70% and 100%. There was an important variability in the type of tube, measurement method, and insertion techniques. It was found that the most common strategies to achieve proper positioning were glabella-calcaneal measurements, gastric air insufflation, and right lateral decubitus. IMPLICATIONS FOR PRACTICE: A transpyloric catheter insertion protocol needs to be established in each neonatal unit, according to the literature findings. IMPLICATIONS FOR RESEARCH: Randomized controlled studies that evaluate the gastric air insufflation technique and other adjuvant measures could elucidate the knowledge gap concerning the correct positioning of transpyloric tubing in newborns and infants.


Subject(s)
Enteral Nutrition , Intubation, Gastrointestinal , Pylorus , Humans , Infant, Newborn , Enteral Nutrition/methods , Intubation, Gastrointestinal/methods , Infant
15.
Pediatr Surg Int ; 40(1): 161, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38916663

ABSTRACT

INTRODUCTION: We sought to determine the effectiveness and utility of two-dimensional shear-wave sonoelastography (2D-SW-SE) in the diagnosis and postoperative follow-up of infantile hypertrophic pyloric stenosis (IHPS). MATERIALS AND METHODS: Twenty-three infants were included in the study, 13 in the IHPS group and 10 in the control group (CG). Preoperative B-mode ultrasonography measurements (longitudinal length and single-wall thickness of the pylorus) and 2D-SW-SE measurements (pylorus tissue stiffness and shear-wave propagation speed) were compared between the groups. The infants with IHPS then underwent Ramstedt pyloromyotomy and were invited for follow-ups on the tenth day and the first, third, and sixth months postoperatively. Measurements taken at the follow-ups were compared with the preoperative values. RESULTS: No differences were found between the groups regarding age, gender, body weight, or week of birth. The pyloric lengths in the IHPS group were longer than in the CG (p < 0.001), and the single-wall thicknesses were thicker (p < 0.001). The pylorus in the IHPS group was four times stiffer than in the CG (27.4 kPa versus 7.66 kPa), and the shear-wave propagation speed in the tissue was higher (1.34 m/s versus 2.69 m/s; p < 0.001). Both values decreased over time in the IHPS group and were normal by the third postoperative month. CONCLUSIONS: 2D-SW-SE can be used as an assistive imaging tool alongside B-mode ultrasound for diagnosing IHPS. It can also be used to identify inadequate surgery by detecting whether the pyloric tissue has softened at follow-up.


Subject(s)
Elasticity Imaging Techniques , Pyloric Stenosis, Hypertrophic , Humans , Pyloric Stenosis, Hypertrophic/diagnostic imaging , Pyloric Stenosis, Hypertrophic/surgery , Elasticity Imaging Techniques/methods , Male , Female , Infant , Follow-Up Studies , Infant, Newborn , Pylorus/diagnostic imaging , Pylorus/surgery , Pyloromyotomy/methods , Treatment Outcome
17.
eNeuro ; 11(6)2024 Jun.
Article in English | MEDLINE | ID: mdl-38834302

ABSTRACT

Linked rhythmic behaviors, such as respiration/locomotion or swallowing/chewing, often require coordination for proper function. Despite its prevalence, the cellular mechanisms controlling coordination of the underlying neural networks remain undetermined in most systems. We use the stomatogastric nervous system of the crab Cancer borealis to investigate mechanisms of internetwork coordination, due to its small, well-characterized feeding-related networks (gastric mill [chewing, ∼0.1 Hz]; pyloric [filtering food, ∼1 Hz]). Here, we investigate coordination between these networks during the Gly1-SIFamide neuropeptide modulatory state. Gly1-SIFamide activates a unique triphasic gastric mill rhythm in which the typically pyloric-only LPG neuron generates dual pyloric-plus gastric mill-timed oscillations. Additionally, the pyloric rhythm exhibits shorter cycles during gastric mill rhythm-timed LPG bursts, and longer cycles during IC, or IC plus LG gastric mill neuron bursts. Photoinactivation revealed that LPG is necessary to shorten pyloric cycle period, likely through its rectified electrical coupling to pyloric pacemaker neurons. Hyperpolarizing current injections demonstrated that although LG bursting enables IC bursts, only gastric mill rhythm bursts in IC are necessary to prolong the pyloric cycle period. Surprisingly, LPG photoinactivation also eliminated prolonged pyloric cycles, without changing IC firing frequency or gastric mill burst duration, suggesting that pyloric cycles are prolonged via IC synaptic inhibition of LPG, which indirectly slows the pyloric pacemakers via electrical coupling. Thus, the same dual-network neuron directly conveys excitation from its endogenous bursting and indirectly funnels synaptic inhibition to enable one network to alternately decrease and increase the cycle period of a related network.


Subject(s)
Brachyura , Ganglia, Invertebrate , Neurons , Neuropeptides , Animals , Brachyura/physiology , Neuropeptides/pharmacology , Neuropeptides/metabolism , Neurons/physiology , Neurons/drug effects , Ganglia, Invertebrate/physiology , Ganglia, Invertebrate/drug effects , Action Potentials/physiology , Action Potentials/drug effects , Nerve Net/physiology , Nerve Net/drug effects , Male , Feeding Behavior/physiology , Feeding Behavior/drug effects , Pylorus/physiology , Pylorus/drug effects , Periodicity
19.
Obes Surg ; 34(7): 2391-2398, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38780835

ABSTRACT

BACKGROUND: One anastomosis gastric bypass (OAGB) is recognized as a standard procedure in metabolic surgery. However, concerns about postoperative bile reflux and nutritional risks are prevalent. Comparatively, sleeve gastrectomy with loop duodenojejunal bypass (SG + LoopDJB) bypasses an equivalent length of the foregut as OAGB while maintaining pyloric function. The role of pylorus function remains to be further elucidated regarding these metabolic procedures' therapeutic outcomes and side effects. METHOD: A retrospective study was conducted in our center to compare the surgical safety and 1-year outcomes of OAGB and SG + LoopDJB regarding type 2 diabetes mellitus (T2DM) remission, weight loss, gastrointestinal disorders, and nutritional status in T2DM patients matched by gender, age, and BMI. RESULTS: The baseline characteristics were comparable between groups. Compared with OAGB, SG + LoopDJB had longer operative time and length of stay (LOS) but similar major postoperative complications. At 1-year follow-up, OAGB has similar diabetes remission (both 91.9%), weight loss effect (28.1 ± 7.1% vs. 30.2 ± 7.0% for %TWL), and lipidemia improvement to SG + LoopDJB (P > 0.05). However, OAGB presented a higher incidence of hypoalbuminemia (11.9% vs. 2.4%, P = 0.026) but a low incidence of gastroesophageal reflux disease (GERD) symptoms (9.5% vs. 26.2%, P = 0.046) than SG + LoopDJB. There was no statistical difference regarding other gastrointestinal disorders and nutritional deficiencies between groups. CONCLUSION: Both OAGB and SG + LoopDJB show comparable, favorable outcomes in weight loss, T2DM remission, and lipidemia improvement at the 1-year follow-up. Pylorus preservation, while increasing surgical difficulty and the risk of de novo GERD, may reduce the risk of postoperative hypoalbuminemia.


Subject(s)
Diabetes Mellitus, Type 2 , Duodenum , Gastrectomy , Gastric Bypass , Obesity, Morbid , Pylorus , Weight Loss , Humans , Diabetes Mellitus, Type 2/surgery , Female , Male , Retrospective Studies , Pylorus/surgery , Gastric Bypass/methods , Gastrectomy/methods , Middle Aged , Treatment Outcome , Duodenum/surgery , Obesity, Morbid/surgery , Adult , Postoperative Complications/epidemiology , Jejunum/surgery , Operative Time , Length of Stay/statistics & numerical data , Anastomosis, Surgical/methods , Nutritional Status
20.
J Neurophysiol ; 132(1): 184-205, 2024 07 01.
Article in English | MEDLINE | ID: mdl-38776457

ABSTRACT

Oscillatory networks underlying rhythmic motor behaviors, and sensory and complex neural processing, are flexible, even in their neuronal composition. Neuromodulatory inputs enable neurons to switch participation between networks or participate in multiple networks simultaneously. Neuromodulation of internetwork synapses can both recruit and coordinate a switching neuron in a second network. We previously identified an example in which a neuron is recruited into dual-network activity via peptidergic modulation of intrinsic properties. We now ask whether the same neuropeptide also modulates internetwork synapses for internetwork coordination. The crab (Cancer borealis) stomatogastric nervous system contains two well-defined feeding-related networks (pyloric, food filtering, ∼1 Hz; gastric mill, food chewing, ∼0.1 Hz). The projection neuron MCN5 uses the neuropeptide Gly1-SIFamide to recruit the pyloric-only lateral posterior gastric (LPG) neuron into dual pyloric- plus gastric mill-timed bursting via modulation of LPG's intrinsic properties. Descending input is not required for a coordinated rhythm, thus intranetwork synapses between LPG and its second network must underlie coordination among these neurons. However, synapses between LPG and gastric mill neurons have not been documented. Using two-electrode voltage-clamp recordings, we found that graded synaptic currents between LPG and gastric mill neurons (lateral gastric, inferior cardiac, and dorsal gastric) were primarily negligible in saline, but were enhanced by Gly1-SIFamide. Furthermore, LPG and gastric mill neurons entrain each other during Gly1-SIFamide application, indicating bidirectional, functional connectivity. Thus, a neuropeptide mediates neuronal switching through parallel actions, modulating intrinsic properties for recruitment into a second network and as shown here, also modulating bidirectional internetwork synapses for coordination.NEW & NOTEWORTHY Neuromodulation can enable neurons to simultaneously coordinate with separate networks. Both recruitment into, and coordination with, a second network can occur via modulation of internetwork synapses. Alternatively, recruitment can occur via modulation of intrinsic ionic currents. We find that the same neuropeptide previously determined to modulate intrinsic currents also modulates bidirectional internetwork synapses that are typically ineffective. Thus, complementary modulatory peptide actions enable recruitment and coordination of a neuron into a second network.


Subject(s)
Brachyura , Neuropeptides , Synapses , Animals , Brachyura/physiology , Synapses/physiology , Neuropeptides/metabolism , Neuropeptides/pharmacology , Neurons/physiology , Ganglia, Invertebrate/physiology , Oligopeptides/pharmacology , Nerve Net/physiology , Pylorus/physiology , Male , Action Potentials/physiology
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