For over a decade, endoscopic hemostatic powders have been used to manage upper gastrointestinal bleeding (UGIB). Various preclinical benchtop and animal models have been developed to evaluate these devices. Multiple companies have released hemostatic powders to market, assessing their safety and efficacy using an established porcine gastric vessel bleed model. This model simulates an aggressive arterial bleed, allowing prototypes to be tested under challenging conditions. It requires a surgeon to insert an artery segment into the gastric lumen and puncture it to produce a bleed. In our study, we tested a control group not included in prior research. We aimed to evaluate the relationship between intragastric pressure and bleed severity by injecting gas used to deliver hemostatic powder to the bleed site, without administering hemostatic powder. Our results indicate that elevated intragastric pressures alone can cause bleed cessation. Additional findings suggest that other factors in the model can lead to false positive hemostasis. This study highlights flaws in the porcine gastric vessel bleed model and underscores the need to develop more robust models for testing hemostatic devices, as no valid endoscopic bleed model currently exists. These experiments stress the importance of vetting preclinical models before acquiring efficacy data.

Maintenance of integrity and function of the gastric mucosa (GM) requires a high regeneration rate of epithelial cells during the whole life span. The health of the gastric epithelium highly depends on redox homeostasis, antioxidant defense and activity of detoxifying systems within the cells as well as robustness of blood supply. Bioactive products of lipid peroxidation, in particular second messengers of free radicals, the bellwether of which is 4-hydroxynonenal (HNE), are important mediators in physiological adaptive reactions and signaling but they are also thought to be implicated in the pathogenesis of numerous gastric diseases. Molecular mechanisms and consequences of increased production of HNE and its protein adducts in response to stressors during acute and chronic gastric injury are well studied. However, several important issues related to the role of HNE in gastric carcinogenesis, tumor growth and progression, the condition of GM after eradication of Helicobacter pylori, or the relevance of antioxidants for HNE-related redox homeostasis in GM still need more studies and new comprehensive approaches. In this regard, preclinical studies and clinical intervention trials are required, which should also include the use of state-of-the-art analytical techniques such as HNE determination by immunohistochemistry and ELISA as well as modern mass-spectroscopy methods.

This is growing recognition of early onset gastrointestinal (GI) malignancies in young adults