Acute nonvariceal upper gastrointestinal (UGI) hemorrhage is a frequent complication associated with significant morbidity and mortality. The most common cause of UGI bleeding is peptic ulcer disease, but the differential diagnosis is diverse and includes tumors; ischemia; gastritis; arteriovenous malformations, such as Dieulafoy lesions; Mallory-Weiss tears; trauma; and iatrogenic causes. Aggressive treatment with early endoscopic hemostasis is essential for a favorable outcome. However, severe bleeding despite conservative medical treatment or endoscopic intervention occurs in 5-10% of patients, requiring surgery or transcatheter arterial embolization. Surgical intervention is usually an expeditious and gratifying endeavor, but it can be associated with high operative mortality rates. Endovascular management using superselective catheterization of the culprit vessel, «sandwich» occlusion, or blind embolization has emerged as an alternative to emergent operative intervention for high-risk patients and is now considered the first-line therapy for massive UGI bleeding refractory to endoscopic treatment. Indeed, many published studies have confirmed the feasibility of this approach and its high technical and clinical success rates, which range from 69 to 100% and from 63 to 97%, respectively, even if the choice of the best embolic agent among coils, cyanaocrylate glue, gelatin sponge, or calibrated particles remains a matter of debate. However, factors influencing clinical outcome, especially predictors of early rebleeding, are poorly understood, and few studies have addressed this issue. This review of the literature will attempt to define the role of embolotherapy for acute nonvariceal UGI hemorrhage that fails to respond to endoscopic hemostasis and to summarize data on factors predicting angiographic and embolization failure.
NSAIDs including loxoprofen increase the risk of UGIB in Japan as in Western countries, with a similar magnitude of association. There was no evidence of biological interaction between NSAIDs and H. pylori infection.
Various growth factors are suggested to be involved in gastric mucosal repair. Our previous studies have shown that exogenous hepatocyte growth factor (HGF) has a proliferative effect on gastric epithelial cells. In the present study, comparison of the maximum proliferative effects and the optimum concentrations of several growth factors revealed that HGF was the most potent mitogen for gastric epithelial cells, as is the case for hepatocytes. Restitution of gastric epithelial cell monolayers was assessed using a round wound restitution model. HGF was the most effective agent for facilitating gastric epithelial restitution among those tested. A binding assay revealed specific binding of HGF to its receptor on gastric epithelial cells. Northern blot analysis confirmed the expression of specific HGF receptor mRNA (c-met) by gastric epithelial cells but not by gastric fibroblasts. To investigate endogenous HGF production, we determined the effect of gastric fibroblast-conditioned medium on epithelial proliferation and restitution. The conditioned medium produced similar effects to HGF and its activity was neutralized by an anti-HGF antibody. In addition, expression of HGF mRNA was detected in gastric fibroblasts but not in gastric epithelial cells. Our immunohistochemical study confirmed these in vitro data by means of demonstrating the existence and localization of HGF at human native gastric mucosa. HGF was localized at fibroblasts under the epithelial cell layer around gastric ulcers. These results suggest that HGF may be a potent endogenous promotor of gastric epithelial cell proliferation and migration, and may contribute to gastric mucosal repair through a paracrine
Acute mesenteric ischemia is a rare life-threatening condition that accounts for approximately one in 1000 hospital admissions. The mortality rate is 50%-69% owing to the absence of specific symptoms and laboratory data, which makes early detection of this condition difficult. If the use of contrast material is possible, biphasic contrast material-enhanced multidetector computed tomography (CT) is the first-line imaging test for early diagnosis of the disease and for differentiation from other causes of acute abdomen. Multidetector CT can depict mesenteric ischemia, its underlying causes, and its severity. Mesenteric ischemia is classified as either acute or chronic. The causes of AMI include arterial embolism, arterial thrombosis, venous thrombosis, and nonocclusive mesenteric ischemia, among which arterial causes are far more common than venous causes. Recently, endovascular procedures such as thrombolysis, thrombectomy, thrombus fragmentation, and stent placement have been successfully and safely performed when the ischemia is reversible. Online DICOM image stacks are available for this article. RSNA, 2018.
The PCM provides better images than the SF. Clinical trials suggest superior detection of both mass and microcalcification by full-field digital PCM over conventional SF mammography.
Although the clinical efficacy of prostaglandins (PGs), especially on gastric mucosal injuries induced by nonsteroidal antiinflammatory drugs, is widely appreciated, their mechanism of action, apart from acid suppression, is quite unclear. In this study, we have established a primary culture system of human gastric fibroblasts and clearly demonstrated that PGs strongly induce the expression of hepatocyte growth factor (HGF) in the fibroblasts, which is mediated by PGE specific receptor, EP2 or EP4. Since HGF facilitates repair and protection of gastric epithelial cells in a paracrine manner, it is assumed that some of the beneficial effects of PGs may be mediated by HGF. To confirm this assumption, we established a simplified in vitro culture gastric mucosal model which consists of gastric epithelial cells and gastric fibroblasts. Using the model, we performed a round wound restitution assay. PGE1 remarkably accelerated restitution which was completely inhibited by anti-HGF antibody, indicating that the action was mediated by HGF. To confirm these in vitro data, we further demonstrated that HGF mRNA expression is downregulated at the edges of nonsteroidal antiinflammatory drug-induced gastric ulcers where PGs should be depleted. In summary, we proposed that gastric fibroblasts are newly recognized targets of PGs, and HGF produced by human gastric fibroblasts may be a key factor for anti-ulcer action of PGs in the stomach. ( J. Clin. Invest. 1996. 98:2604-2611.)
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