Microplastic in Gastric Fasting Liquid and Associated Gastric Pathology.

OBJECTIVE: To determine the presence of microplastics in the stomach, and the relationship between pathological changes in stomach tissue and microplastics. STUDY DESIGN: An analytical study. Place and Duration of the Study: Department of Internal Medicine, Sorgun State Hospital, Yozgat, Turkiye, from December 2022 to November 2023. METHODOLOGY: Fasting gastric fluid sampling and endoscopic sampling including mucosal and submucosal layers from the antrum were performed. The pH values of the gastric fluids were recorded. Samples were analysed gradually by adding iron solution, hydrogen peroxide, and sodium chloride (NaCl) in a beaker at 75 degrees for 30 minutes. Biopsy materials obtained from antrum were examined histopathologically and reported according to the Sydney classification. The relationship between gastric biopsy results and the presence of microplastic was evaluated using Chi-square test. The significance level was taken as p <0.005. RESULTS: The study included 61 individuals. The presence of microplastics was detected in 17 (27.86%) gastric fluid samples obtained from the individuals. A significant correlation was found between increased activity and inflammation in antrum biopsy and the presence of microplastic (χ2 = 8.55 p = 0.014; χ2 = 25.75, p = 0.001). The relationship between atrophy, metaplasia, and Helicobacter pylori in gastric tissue and the presence of microplastic was statistically insignificant (p >0.05). CONCLUSION: Microplastics were detected in gastric fasting fluid. These materials can cause histopathologic changes and inflammation in the gastric antrum. KEY WORDS: H. pylori, Intestinal metaplasia, Inflammation, Microplastic, Plastic, Sydney classification.

A head-to-head comparison of polymer interaction with mucin from porcine stomach and bovine submaxillary glands.

Native mucus is heterogeneous, displays high inter-individual variation and is prone to changes during harvesting and storage. To overcome the lack of reproducibility and availability of native mucus, commercially available purified mucins, porcine gastric mucin (PGM) and mucin from bovine submaxillary gland (BSM), have been widely used. However, the question is to which extent the choice of mucin matters in studies of their interaction with polymers as their composition, structure and hence physicochemical properties differ. Accordingly, the interactions between PGM or BSM with two widely used polymers in drug delivery, polyethylene oxide and chitosan, was studied with orthogonal methods: turbidity, dynamic light scattering, and quartz crystal microbalance with dissipation monitoring. Polymer binding and adsorption to the two commercially available and purified mucins, PGM and BSM, is different depending on the mucin type. PEO, known to interact weakly with mucin, only displayed limited interaction with both mucins as confirmed by all employed methods. In contrast, chitosan was able to bind to both PGM and BSM. Interestingly, the results suggest that chitosan interacts with BSM to a greater extent than with PGM indicating that the choice of mucin, PGM or BSM, can affect the outcome of studies of mucin interactions with polymers.

Characterization of giant endocrine cells in the fundic stomach of African catfish (Clarias gariepinus) demonstrated by histochemical, immunohistochemical and ultrastructure microscopy methods suggesting their role in immunity.

Endocrine cells in the fundic stomach of Clarias gariepinus were characterized in this work using transmission electron microscopy, immunohistochemistry, and histochemistry. Performic acid mixed with alcian blue pH2.5 and silver stain were among the histochemical stains used for endocrine cells. Endocrine cells can be found in the epithelium, lamina propria, submucosa, muscular layer, serosa, and the area between the stomach glands. Endocrine cells with one or more nuclei were found. Endocrine cells were studied using CD3, CD21, and CD68 in an immunohistochemistry analysis. The expression of the lymphocyte marker CD3 by endocrine cells is remarkable. In addition, they had a strong immunological response to CD21 and CD68, which are characteristics of phagocytic cells. Granules of varied sizes and electron densities are packed densely into the cytoplasm of the cells, as seen by transmission electron microscopy. We propose that endocrine cells play a crucial role in immune defense. The role of endocrine cells in the gut's immune system is an area that needs further investigation.

Two cases of intrathoracic herniation of the gastric tube from the retrosternal route requiring reoperation after oesophagectomy.

Intrathoracic herniation of the gastric tube pulled up through the retrosternal route after oesophagectomy is relatively rare and usually can be managed by conservative treatment.We present two patients who needed reoperation for intrathoracic herniation of gastric tube after minimally invasive oesophagectomy for thoracic oesophageal cancer. Postoperatively, both patients showed herniation and acute twist of the gastric tube. Due to the twist of the gastric tube, one patient had ischaemic change of the proximal tip of the gastric tube, and the other patient showed delayed gastric emptying, both of which led to surgical repairs. In this case report, we discuss why the herniation of gastric tube from the retrosternal route occurs, how to decide to do reoperation and how to prevent this complication.

Dynamic in vitro gastric digestion of skimmed milk using the NERDT, an advanced human biomimetic digestion system.

The main objective of this study was to assess the ability of the NEar Real Digestive Tract (NERDT), a computer-controlled biomimetic in vitro digestion system that considers the biomechanics of the stomach, to reproduce physiologically relevant features of skimmed milk gastric digestion. A second objective was to evaluate the influence of pepsin on the gastric coagulation and emptying of milk proteins from experiments performed with and without pepsin. A mass balance model over the stomach, assuming a perfectly stirred reactor behaviour, has been developed. The results show that the NERDT can adequately reproduce the targeted kinetics of gastric acidification and emptying, with a sieving effect that naturally leads to a delayed emptying of caseins. Milk coagulated earlier and more chyme was emptied towards the end of the experiments in the presence of pepsin than without, hence illustrating the key influence of pepsin on the gastric coagulation of caseins and subsequent hydrolysis and emptying of dairy particles. Overall, this study shows that the NERDT can be adequately controlled to achieve desired gastric digestion conditions, and appears to be a very useful tool to further improve the knowledge of the gastric digestion behaviour of complex foods such as milk.

Inflammation promotes stomach epithelial defense by stimulating the secretion of antimicrobial peptides in the mucus.

The mucus serves as a protective barrier in the gastrointestinal tract against microbial attacks. While its role extends beyond merely being a physical barrier, the extent of its active bactericidal properties remains unclear, and the mechanisms regulating these properties are not yet understood. We propose that inflammation induces epithelial cells to secrete antimicrobial peptides, transforming mucus into an active bactericidal agent. To investigate the properties of mucus, we previously developed mucosoid culture models that mimic the healthy human stomach epithelium. Similar to organoids, mucosoids are stem cell-driven cultures; however, the cells are cultivated on transwells at air-liquid interface. The epithelial cells of mucosoids form a polarized monolayer, allowing differentiation into all stomach lineages, including mucus-secreting cells. This setup facilitates the secretion and accumulation of mucus on the apical side of the mucosoids, enabling analysis of its bactericidal effects and protein composition, including antimicrobial peptides. Our findings show that TNFα, IL1ß, and IFNγ induce the secretion of antimicrobials such as lactotransferrin, lipocalin2, complement component 3, and CXCL9 into the mucus. This antimicrobial-enriched mucus can partially eliminate Helicobacter pylori, a key stomach pathogen. The bactericidal activity depends on the concentration of each antimicrobial and their gene expression is higher in patients with inflammation and H.pylori-associated chronic gastritis. However, we also find that H. pylori infection can reduce the expression of antimicrobial encoding genes promoted by inflammation. These findings suggest that controlling antimicrobial secretion in the mucus is a critical component of epithelial immunity. However, pathogens like H. pylori can overcome these defenses and survive in the mucosa.

How Japanese eels escape from the stomach of a predatory fish.

Predation shapes diversity in the defensive tactics of prey. One specialized defensive tactic is to escape the digestive system of the predator after capture1,2,3,4,5,6,7,8. While most of these defensive tactics involve passive ejection alive from predators' mouths and vents1,2,3,4,5, active escape from the digestive tracts of predators has recently been observed in certain invertebrate species6,7 and fish8. However, no study has yet uncovered the behavioral patterns and escape routes of the prey within a predator's digestive tract. Here, we report the sequential escape processes of the Japanese eel Anguilla japonica from capture to escape via the gills of predatory fish Odontobutis obscura using an X-ray video system. All captured eels had at least one portion of their bodies swallowed into the stomach of the predator. Surprisingly, after being swallowed, most individuals attempted to escape by going back up the digestive tract towards the esophagus and gill, and some of them succeeded in escaping via the predator's gill. Some eels, whose entire bodies were completely inside the stomach, exhibited circling behavior along the stomach, seemingly searching for possible escape routes. An electro-anesthetization experiment revealed that eels utilize various escape routes through gill clefts, rather than just one.

Magnamosis improves the healing of gastrojejunal anastomosis and down-regulates TGF-ß1 and HIF-1α in rats.

This study elucidated the unique pathological features of tissue healing by magnamosis and revealed the changes in landmark molecule expression levels related to collagen synthesis and tissue hypoxia. Forty-eight male Sprague-Dawley rats were divided into the magnamosis and suture anastomosis groups, and gastrojejunal anastomosis surgery was performed. Rats were dissected at 6, 24, and 48 h and 5, 6, 8, 10, and 12 days postoperatively. Hematoxylin, eosin, and Masson's trichrome staining were used to evaluate granulation tissue proliferation and collagen synthesis density at the anastomosis site. Immunohistochemistry was used to measure TGF-ß1 and HIF-1α expression levels. Magnamosis significantly shortened the operation time, resulting in weaker postoperative abdominal adhesions (P < 0.0001). Histopathological results showed a significantly lower granulation area in the magnamosis group than in the suture anastomosis group (P = 0.0388), with no significant difference in the density of collagen synthesis (P = 0.3631). Immunohistochemistry results indicated that the magnamosis group had significantly lower proportions of TGF-ß1-positive cells at 24 (P = 0.0052) and 48 h (P = 0.0385) postoperatively and HIF-1α-positive cells at 24 (P = 0.0402) and 48 h postoperatively (P = 0.0005). In a rat model of gastrojejunal anastomosis, magnamosis leads to improved tissue healing at the gastrojejunal anastomosis, associated with downregulated expression levels of TGF-ß1 and HIF-1α.

Autoimmune gastritis studies and gastric cancer: True renaissance or bibliometric illusion.

A bibliometric analysis of studies dedicated to autoimmune gastritis (AIG) recently published demonstrated a noteworthy surge in publications over the last three years. This can be explained by numerous publications from different regions of the world reporting the results of several studies that stimulated reassessment of our view of AIG as a precancerous condition. Follow-up studies and retrospective analyses showed that the risk of gastric cancer (GC) in AIG patients is much lower than expected if the patients ever being infected with Helicobacter pylori (H. pylori) were excluded. The low prevalence of precancerous lesions, such as the incomplete type of intestinal metaplasia, may explain the low risk of GC in AIG patients because the spasmolytic polypeptide-expressing metaplasia commonly observed in AIG does not involve clonal reprogramming of the gastric gland and can be considered as an adaptive change rather than a true precancerous lesion. However, changes in gastric secretion due to the progression of gastric atrophy during the course of AIG cause changes in the gastric mic-robiome, stimulating the growth of bacterial species such as streptococci, which may promote the development of precancerous lesions and GC. Thus, Streptococcus anginosus exhibited a robust proinflammatory response and induced the gastritis-atrophy-metaplasia-dysplasia sequence in mice, reproducing the well-established process for carcinogenesis associated with H. pylori. Prospective studies in H. pylori-naïve patients evaluating gastric microbiome changes during the long-term course of AIG might provide an explanation for the enigmatic increase in GC incidence in the last decades in younger cohorts, which has been reported in economically developed countries.

Elucidation of Degradation Behavior of Barbiturates in Artificial Gastric Juice: Study on Degradability of Drugs in Stomach (V).

The gastric stability of eight barbiturates (BARs) (barbital, primidone, allobarbital, phenobarbital, cyclobarbital, pentobarbital, secobarbital, and thiobutabarbital (TBB)) was examined in artificial gastric juice using LC/UV detection. Among the eight BARs, only TBB was degraded at higher temperatures. Furthermore, the degradation product of TBB was isolated, structurally analyzed, and finally identified as 5-butan-2-yl-5-ethyl-1,3-diazinane-2,4,6-trione, also known as butabarbital. The study elucidated that butabarbital was formed by substituting the sulfur atom of the carbonyl group at the 2-position of TBB with an oxygen atom under acidic condition.

This is a successful removal of more than 450 pieces of metal objects from a patient's stomach: a case report.

BACKGROUND: Ingestion of foreign bodies may be seen unconsciously or intentionally in patients with mental health problems. Most cases pass through the esophagus slowly; however, in some cases, the tumor may be located in narrower areas of the digestive tract that require endoscopic or surgical intervention. This study describes a rare case of successful removal of more than 450 pieces of metal objects from the stomach of a 36-year-old man via ingestion of foreign bodies at Imam Khomeini Hospital in Ahvaz. CASE PRESENTATION: A 36-year-old male patient (Aryan race) presented with complaints of chronic abdominal pain, frequent vomiting, and intolerance to liquids and food. The patient's companions mentioned a history of gradual ingestion of small metal objects 3 months prior. The patient was conscious and had stable vital signs. In the patient's X-ray and endoscopy, multiple metal objects inside the patient's stomach were observed, causing gastric outlet obstruction. The patient underwent gastrostomy surgery, and 452 screws, nuts, keys, stones, and other metal parts weighing 2900 g were removed from the stomach. Five days after the operation, the patient was transferred to the psychiatric service in good general condition and was diagnosed with psychosis, and her condition returned to normal at follow-up. CONCLUSION: Successful removal of this foreign body is rare. In chronic abdominal pain, especially in the context of psychiatric disorders, attention should be given to the ingestion of foreign bodies. In swallowing large amounts of sharp and metallic foreign objects, surgical intervention is necessary, especially in cases of obstruction, and saves the patient's life.

Interstitial cells of the sip syncytium regulate basal membrane potential in murine gastric corpus.

Smooth muscle cells (SMCs), Interstitial cells of Cajal (ICC) and Platelet-derived growth factor receptor α positive (PDGFRα+) cells form an integrated, electrical syncytium within the gastrointestinal (GI) muscular tissues known as the SIP syncytium. Immunohistochemical analysis of gastric corpus muscles showed that c-KIT+/ANO1+ ICC-IM and PDGFRα+ cells were closely apposed to one another in the same anatomical niches. We used intracellular microelectrode recording from corpus muscle bundles to characterize the roles of intramuscular ICC and PDGFRα+ cells in conditioning membrane potentials of gastric muscles. In muscle bundles, that have a relatively higher input impedance than larger muscle strips or sheets, we recorded an ongoing discharge of stochastic fluctuations in membrane potential, previously called unitary potentials or spontaneous transient depolarizations (STDs) and spontaneous transient hyperpolarizations (STHs). We reasoned that STDs should be blocked by antagonists of ANO1, the signature conductance of ICC. Activation of ANO1 has been shown to generate spontaneous transient inward currents (STICs), which are the basis for STDs. Ani9 reduced membrane noise and caused hyperpolarization, but this agent did not block the fluctuations in membrane potential quantitatively. Apamin, an antagonist of small conductance Ca2+-activated K+ channels (SK3), the signature conductance in PDGFRα+ cells, further reduced membrane noise and caused depolarization. Reversing the order of channel antagonists reversed the sequence of depolarization and hyperpolarization. These experiments show that the ongoing discharge of STDs and STHs by ICC and PDGFRα+ cells, respectively, exerts conditioning effects on membrane potentials in the SIP syncytium that would effectively regulate the excitability of SMCs.

Morphology of the Digestive Tube of the Amazonian Freshwater Stingray Potamotrygon wallacei (Elasmobranchii: Potamotrygonidae): A Stereological Approach.

This work aimed to describe and quantify the tissue components of the digestive tube of the neotropical freshwater stingray, Potamotrygon wallacei. For this, conventional histology and stereological methods were used to estimate tissue volume. The volumes of the four fundamental layers and the tissue components in the stomach (cardiac and pyloric) and spiral intestine were also estimated. In the cardiac stomach, the mucosa layer occupies 44.7% of the total volume of the organ wall. The gastric glands are the main components, and these structures alone represent 49.7% of this layer. This large number of gastric glands suggests a high potential for processing food items with a high protein content. The stereological methods were sensitive enough to show a reduction in the volume of the gastric glands from the cardiac region toward the pyloric region. Gastric glands are absent in the pyloric region of the stomach. However, the muscularis becomes thicker towards the pyloric region. The increase in smooth muscle thickness is due to the thickening of the inner muscular layer. This suggests that the role of the pyloric stomach may be related to the mixing of the chyme and assisting its passage to the spiral intestine. In the spiral intestine, data on the volume of the mucosa layer (and epithelial lining) suggest that the spiral valve has a large absorptive area. In several respects, the morphology of the digestive tube of P. wallacei is similar to that of other batoids. However, its slight morphological variations may be related to the habitat specificity of this species.

A novel compartmental approach for modeling stomach motility and gastric emptying.

The stomach, a central organ in the Gastrointestinal (GI) tract, regulates the processing of ingested food through gastric motility and emptying. Understanding the stomach function is crucial for treating gastric disorders. Experimental studies in this field often face difficulties due to limitations and invasiveness of available techniques and ethical concerns. To counter this, researchers resort to computational and numerical methods. However, existing computational studies often isolate one aspect of the stomach function while neglecting the rest and employ computationally expensive methods. This paper proposes a novel cost-efficient multi-compartmental model, offering a comprehensive insight into gastric function at an organ level, thus presenting a promising alternative. The proposed approach divides the spatial geometry of the stomach into four compartments: Proximal/Middle/Terminal antrum and Pyloric sphincter. Each compartment is characterized by a set of ordinary differential equations (ODEs) with respect to time to characterize the stomach function. Electrophysiology is represented by simplified equations reflecting the "slow wave behavior" of Interstitial Cells of Cajal (ICC) and Smooth Muscle Cells (SMC) in the stomach wall. An electro-mechanical coupling model translates SMC "slow waves" into smooth muscle contractions. Muscle contractions induce peristalsis, affecting gastric fluid flow velocity and subsequent emptying when the pyloric sphincter is open. Contraction of the pyloric sphincter initiates a retrograde flow jet at the terminal antrum, modeled by a circular liquid jet flow equation. The results from the proposed model for a healthy human stomach were compared with experimental and computational studies on electrophysiology, muscle tissue mechanics, and fluid behavior during gastric emptying. These findings revealed that each "ICC" slow wave corresponded to a muscle contraction due to electro-mechanical coupling behavior. The rate of gastric emptying and mixing efficiency decreased with increasing viscosity of gastric liquid but remained relatively unchanged with gastric liquid density variations. Utilizing different ODE solvers in MATLAB, the model was solved, with ode15s demonstrating the fastest computation time, simulating 180 s of real-time stomach response in just 2.7 s. This multi-compartmental model signifies a promising advancement in understanding gastric function, providing a cost-effective and comprehensive approach to study complex interactions within the stomach and test innovative therapies like neuromodulation for treating gastric disorders.

Adverse effects of metamizole on heart, lung, liver, kidney, and stomach in rats.

BACKGROUND: Metamizole is banned in some countries because of its toxicity, although it is widely used in some European countries. In addition, there is limited information on its safety profile, and it is still debated whether it is toxic to the heart, lungs, liver, kidneys, and stomach. AIMS: Our study investigated the effects of metamizole on the heart, lung, liver, kidney, and stomach tissues of rats. METHODS: Eighteen rats were divided into three groups, wassix healthy (HG), 500 mg/kg metamizole (MT-500), and 1000 mg/kg metamizole (MT-1000). Metamizole was administered orally twice daily for 14 days. Meanwhile, the HG group received pure water orally. Biochemical, histopathologic, and macroscopic examinations were performed on blood samples and tissues. RESULTS: Malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), and catalase (CAT) in the lung and gastric tissues of MT-500 and MT-1000 groups were almost the same as those of the HG (p > 0.05). However, MDA levels in the heart and liver tissues of MT-500 and MT-1000 groups were higher (p < 0.05) compared to the HG, while tGSH levels and SOD, and CAT activities were lower (p < 0.05). MDA levels of MT-500 and MT-1000 groups in the kidney tissue increased the most (p < 0.001), and tGSH levels and SOD and CAT activities decreased the most (p < 0.001) compared to HG. Metamizole did not cause oxidative damage in the lung and gastric tissue. While metamizole did not change troponin levels, it significantly increased alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), and creatinine levels compared to HG. Histopathologically, mild damage was detected in heart tissue, moderate damage in liver tissue, and severe damage in renal tissue. However, no histopathologic damage was found in any groups' lung and gastric tissues. CONCLUSION: Metamizole should be used under strict control in patients with cardiac and liver diseases and it would be more appropriate not to use it in patients with renal disease.

Gastric Bezoars: A Retrospective Analysis of 44 Cases.

BACKGROUND Gastric bezoars are a relatively rare condition. We aim to summarize the clinical characteristics and endoscopic features of patients with gastric bezoars, and analyze the treatment process. MATERIAL AND METHODS The medical records of 44 patients with gastric bezoars treated at Henan Provincial People's Hospital from September 2017 to December 2023 were retrospectively reviewed. RESULTS Among the 44 patients, there were 20 males and 24 females. The average age was 55.36±15.17 years. Abdominal pain was the primary symptom in patients with gastric bezoars. Single gastric bezoars were more common than multiple ones, accounting for 86.4% of all cases. Endoscopic examination revealed ulcers in 36 (81.8%) patients, mainly at the gastric angle and antrum. Single ulcers were more common than multiple ulcers, with most ulcer diameters being less than 2 cm. The occurrence of ulcers was not significantly related to patient age or the size of the bezoars. Endoscopic examination confirmed complete clearance of gastric bezoars in 30 patients. In the 26 patients treated successfully under endoscopy, the number of endoscopic treatments ranged from 1 to 4, with an average of 1.27 interventions per patient. The interval for the second endoscopic re-examination ranged from 2 to 6 days, with an average of 3.87±1.22 days. CONCLUSIONS The most common type of gastric bezoar is phytobezoars. There is a close association between ulcer formation and gastric bezoars. Endoscopic therapy combined with oral treatment can effectively treat gastric bezoars. Most patients require only 1 endoscopic treatment to be successful. The appropriate interval for a follow-up endoscopy after the first endoscopic treatment is around 4 days.

Helicobacter pylori induces the expression of Lgr5 and stem cell properties in gastric target cells.

Helicobacter pylori infection predisposes carriers to a high risk of developing gastric cancer. The cell-of-origin of antral gastric cancer is the Lgr5+ stem cell. Here, we show that infection of antrum-derived gastric organoid cells with H. pylori increases the expression of the stem cell marker Lgr5 as determined by immunofluorescence microscopy, qRT-PCR, and Western blotting, both when cells are grown and infected as monolayers and when cells are exposed to H. pylori in 3D structures. H. pylori exposure increases stemness properties as determined by spheroid formation assay. Lgr5 expression and the acquisition of stemness depend on a functional type IV secretion system (T4SS) and at least partly on the T4SS effector CagA. The pharmacological inhibition or genetic ablation of NF-κB reverses the increase in Lgr5 and spheroid formation. Constitutively active Wnt/ß-catenin signaling because of Apc inactivation exacerbates H. pylori-induced Lgr5 expression and stemness, both of which persist even after eradication of the infection. The combined data indicate that H. pylori has stemness-inducing properties that depend on its ability to activate NF-κB signaling.

Multivariate analysis of factors associated with the successful prediction of initial blind placement of a nasointestinal tube in the stomach based on X-ray imaging: a retrospective, single-center study.

BACKGROUND: Patients in the intensive care unit (ICU) are highly susceptible to malnutrition, and while enteral nutrition via nasogastric tube is the preferred method, there is a risk of inadvertent reflux and aspiration. Therefore, clinicians have turned to nasointestinal tubes (NET) for enteral nutrition as an alternative option. But the precise localization of NET presents an ongoing challenge. We proposed an innovative approach to provide a valuable reference for clinicians involved in NET placement. METHOD: Data were obtained retrospectively from the medical records of adult patients with a high risk of aspiration or gastric feeding intolerance who had a NET placed in the ICU of Zhejiang Provincial People's Hospital between October 1, 2017, and October 1, 2023. The collected data were subjected to statistical analysis using SPSS and R software. RESULT: There were 494 patients who met the inclusion and exclusion criteria. The first-pass success rate was 81.4% (n = 402). The success of a patient's initial NET placement was found to be associated with Angle SPC and Distance CP, as determined by univariate analysis (25.6 ± 16.7° vs. 41.9 ± 18.0°, P < 0.001; 40.0 ± 26.2 mm vs. 62.0 ± 31.8 mm, P < 0.001, respectively). By conducting a multivariate regression analysis, we identified a significant association between pyloric types and the success rate of placing NET (OR 29.559, 95%CI 14.084-62.038, P < 0.001). CONCLUSION: Angle SPC, Distance CP, and the type of pylorus are independently associated with successful initial placement of NET. Besides, patients with the outside type of pylorus (OP-type) exhibit a higher rate of initial placement success.