Esophageal and gastric cancers are both common and deadly. Patients present most often after disease progression and survival is therefore poor. Due to demographic variability and recent changes in disease incidence, ...Esophageal and gastric cancers are both common and deadly. Patients present most often after disease progression and survival is therefore poor. Due to demographic variability and recent changes in disease incidence, much emphasis has been placed on studying risk factors for both esophageal and gastric cancers. However, with increasing understanding of these diseases, low survival rates persist and continued intensive studies are necessary to optimize treatment plans. This review article discusses updates in the evolving epidemiology, clinical presentation, risk factors, and diagnostic and treatment modalities of esophageal and gastric cancers.展开更多
The incidence and mortality of gastric cancer have fallen dramatically in US and elsewhere over the past several decades. Nonetheless, gastric cancer remains a major public health issue as the fourth most common cance...The incidence and mortality of gastric cancer have fallen dramatically in US and elsewhere over the past several decades. Nonetheless, gastric cancer remains a major public health issue as the fourth most common cancer and the second leading cause of cancer death worldwide. Demographic trends differ by tumor location and histology. While there has been a marked decline in distal, intestinal type gastric cancers, the incidence of proximal, diffuse type adenocarcinomas of the gastric cardia has been increasing, particularly in the Western countries. Incidence by tumor sub-site also varies widely based on geographic location, race, and socioeconomic status. Distal gastric cancer predominates in developing countries, among blacks, and in lower socioeconomic groups, whereas proximal tumors are more common in developed countries, among whites, and in higher socio-economic classes. Diverging trends in the incidence of gastric cancer by tumor location suggest that they may represent two diseases with different etiologies. The main risk factors for distal gastric cancer include Helicobacter pylori (H pylori) infection and dietary factors, whereas gastroesophageal reflux disease and obesity play important roles in the development of proximal stomach cancer. The purpose of this review is to examine the epidemiology and risk factors of gastric cancer, and to discuss strategies for primary prevention.展开更多
AIM: To identify the clinicopathological characteristics of lymph node-negative gastric carcinoma, and also to evaluate outcome indicators in the lymph node-negative patients.METHODS: Of 2848 gastric carcinoma patie...AIM: To identify the clinicopathological characteristics of lymph node-negative gastric carcinoma, and also to evaluate outcome indicators in the lymph node-negative patients.METHODS: Of 2848 gastric carcinoma patients, 1524 (53.5%) were lymph nede-negative. A statistical analysis was performed using the Cox model to estimate outcome indicators. RESULTS: There was a significant difference in the recurrence rate between lymph nede-negative and lymph node-positive patients (14.4% vs 41.0%, P〈0.001). The 5-year survival rate was significantly lower in lymph node-positive than in lymph node-negative patients (31.1% vs 77.4%, P〈0.001). Univariate analysis revealed that the following factors influenced the 5-year survival rate: patient age, tumor size, depth of invasion, tumor location, operative type, and tumor stage at initial diagnosis. The Cox proportional hazard regression model revealed that tumor size, serosal invasion, and curability were independent, statistically significant, prognostic indicators of lymph node-negative gastric carcinoma. CONCLUSION: Lymph node-negative patients have a favorable outcome attributable to high curability, but the patients with relatively large tumors and serosal invasion have a poor prognosis. Curability is one of the most reliable predictors of long-term survival for lymph nodenegative gastric carcinoma patients.展开更多
The human gastrointestinal (GI) tract is colonized by non-pathogenic commensal microflora and frequently exposed to many pathogenic organisms. For the maintenance of GI homeostasis, the host must discriminate betwee...The human gastrointestinal (GI) tract is colonized by non-pathogenic commensal microflora and frequently exposed to many pathogenic organisms. For the maintenance of GI homeostasis, the host must discriminate between pathogenic and non-pathogenic organisms and initiate effective and appropriate immune and inflammatory responses. Mammalian tolllike receptors (TLRs) are members of the patternrecognition receptor (PRR) family that plays a central role in the initiation of innate cellular immune responses and the subsequent adaptive immune responses to microbial pathogens. Recent studies have shown that gastrointestinal epithelial cells express almost all TLR subtypes characterized to date and that the expression and activation of TLRs in the GI tract are tightly and coordinately regulated. This review summarizes the current understanding of the crucial dual roles of TLRs in the development of host innate and adaptive immune responses to GI infections and the maintenance of the immune tolerance to commensal bacteria through downregulation of surface expression of TLRs in intestinal epithelial cells.展开更多
To investigate the effects of leptin (1-20μg/kg) on acidified ethanol (AE)- and indomethacin (Indo)-induced gastric lesions in rats and compare it with ranitidine, lansoprazole, and omeprazole and to determine ...To investigate the effects of leptin (1-20μg/kg) on acidified ethanol (AE)- and indomethacin (Indo)-induced gastric lesions in rats and compare it with ranitidine, lansoprazole, and omeprazole and to determine its mechanisms of actions.METHODS: Gastric ulcers, which were approximately 1 mm in width, formed in the glandular portion of the gastric mucosa produced by oral administration of either AE or Indo were taken as ulcer index. The inhibitory effect of subcutaneous administration of leptin, two proton pump inhibitors (PPIs) lansoprazole and omeprazole, or H2-receptor antagonist ranitidine 30 min before AE or Indo was evaluated.A radioimmunoassay was used to determine the PGE2 concentration in the homogenate of the glandular portion of the stomach. We performed histological study of the glandular stomach for the evaluation of total, acidic, and sulfated mucus content.RESULTS: Subcutaneous administration of leptin, two PPI slansoprazole and omeprazole or H2-receptor antagonist ranitidine 30 min before AE or Indo produced a dosedependent and reproducible inhibition of gastric ulcers (GUs). This inhibition was found to be more potent than other antagonists used. In N^G-nitro L-arginine methyl ester (L-NAME)-pretreated animals, the ulcer prevention ability of leptin in AE-induced ulcer was significantly reduced,compared to rats without L-NAME pretreatment. However,the ulcer prevention ability of leptin was not altered by L-NAME treatment in Indo-induced ulcers. Leptin produced a dose-dependent increase in PGE2 level in the gastric glandular tissues. Leptin also increased mucus secretion.CONCLUSION: The results of the present study show that leptin inhibits GU formation by AE or Indo in a dosedependent and reproducible manner in rats. The results also suggest that leptin prevents ulcer formation by increasing the activities of the cyclo-oxygenase and/or nitric oxide pathways and by increasing mucus secretion.展开更多
Bleeding from gastric varices has been successfully treated by endoscopic modalities. Once the bleeding from the gastric varices is stabilized, endoscopic treatment and/or interventional radiology should be performed ...Bleeding from gastric varices has been successfully treated by endoscopic modalities. Once the bleeding from the gastric varices is stabilized, endoscopic treatment and/or interventional radiology should be performed to eradicate varices completely. Partial splenic artery embolization is a supplemental treatment to prolong the obliteration of the veins feeding and/or draining the varices. The overall incidence of bleeding from gastric varices is lower than that from esophageal varices. No studies to date have defi nitively characterized the causal factors behind bleeding from gastric varices. The initial episodes of bleeding from esophageal varices or gastric varices without prior treatment may be at least partly triggered by a violation of the mucosal barrier overlying varices. This is especially likely in the case of varices of the fundus. In view of the high rate of hemostasis achieved among bleeding gastric varices, treatment should be administered in selective cases. Among untreated cases, steps to prevent gastric mucosal injury confer very important protection against gastric variceal bleeding.展开更多
AIM: To investigate the microsatellite instability (MSI) in cancer and pre-cancerous lesions of the stomach and its mechanisms underlying the development of gastric cancer.METHODS: Thirty-six gastric cancer samples we...AIM: To investigate the microsatellite instability (MSI) in cancer and pre-cancerous lesions of the stomach and its mechanisms underlying the development of gastric cancer.METHODS: Thirty-six gastric cancer samples were obtained from patients undergoing surgery. Forty-one gastric mucosa samples with dysplasia and 51 with intestinal metaplasia (IM) were obtained from patients with chronic gastritis undergoing gastro-endoscopy. Genomic DNA was extracted from the samples. Silver staining single strand conformation polymorphis-polymerize chain reaction (SSCP-PCR) was used to screen MSI markers at 5 loci (Bat-25, Bat-26, D5S346, D17S250, and D2S123)in fresh tissues and formalin-fixed, paraffin-embedded samples and their corresponding normal gastric mucosa.RESULTS: The abnormal shifting of the single-strand DNA (MSI) was identified in 21 out of 36 (58.3%) gastric cancers.Seven cases showed high-level MSI (two or more loci altered) and 14 showed low-level MSI (one locus altered).Gastric cancer with MSI had a tendency to be located in the distal stomach. MSI was also detected in 11 out of 41(26.8%) dysplasia samples and in 9 of 51 (17.6%) IM samples respectively. Three cases of dysplasia and one case of IM showed high-level MSI. Eight cases of dysplasia and 8 cases of IM displayed low-level MSI. MIS in IM was found only in moderate or severe-grade IM. No association was detected between MSI and dysplasia grade.CONCLUSION: Accumulation of MSI in dysplasia and intestinal metaplasia of gastric mucosa may be an early molecular event during gastric carcinogenesis and may contribute to the acquisition of transformed cell phenotype and the development of gastric cancer.展开更多
Metastatic breast cancer involving the hepatobiliary tract or ascites secondary to peritoneal carcinomatosis has been well described. Luminal gastrointestinal tract involvement is less common and recognition of the ra...Metastatic breast cancer involving the hepatobiliary tract or ascites secondary to peritoneal carcinomatosis has been well described. Luminal gastrointestinal tract involvement is less common and recognition of the range of possible presentations is important for early and accurate diagnosis and treatment. We report 6 patients with a variety of presentations of metastatic breast cancer of the luminal gastrointestinal tract. These include oropharyngeal and esophageal involvement presenting as dysphagia with one case of pseudoachalasia, a linitis plastica-like picture with gastric narrowing and thickened folds, small bowel obstruction and multiple strictures mimicking Crohn’s disease, and a colonic neoplasm presenting with obstruction. Lobular carcinoma, representing only 10% of breast cancers is more likely to metastasize to the gastrointestinal tract. These patients presented with gastrointestinal manifestations after an average of 9.5 years and as long as 20 years from initial diagnosis of breast cancer. Given the increased survival of breast cancer patients with current therapeutic regimes, more unusual presentations of metastatic disease, including involvement of the gastrointestinal tract can be anticipated.展开更多
AIM: To investigate the dynamic functional and ultrastructural changes of gastric parietal cells induced by water immersion-restraint stress (WRS) in rats.METHODS: WRS model of Sprague-Dawley (SD) rats was estab...AIM: To investigate the dynamic functional and ultrastructural changes of gastric parietal cells induced by water immersion-restraint stress (WRS) in rats.METHODS: WRS model of Sprague-Dawley (SD) rats was established. Fifty-six male SD rats were randomly divided into control group, stress group and post-stress group. The stress group was divided into 1, 2 and 4 h stress subgroups. The post-stress group was divided into 24, 48 and 72 h subgroups. The pH value of gastric juice, ulcer index (UI) of gastric mucosa and H^+, K^+- ATPase activity of gastric parietal cells were measured. Ultrastructural change of parietal cells was observed under transmission electron microscope (TEM).RESULTS: The pH value of gastric juice decreased time-dependently in stress group and increased in post-stress group. The H^+, K^+-ATPase activity of gastric parietal cells and the UI of gastric mucosa increased time-dependently in stress group and decreased in poststress group. Compared to control group, the pH value decreased remarkably (P = 0.0001), the UI and H^+, K^+- ATPase activity increased significantly (P = 0.0001, P = 0.0174) in 4 h stress subgroup. UI was positively related with stress time (r = 0.9876, P 〈 0.01) but negatively with pH value (r = -0.8724, P 〈 0.05). The parietal cells became active in stress group, especially in 4 h stress subgroup, in which plenty of intracellular canalicular and mitochondria were observed under TEM. In post-stress group, the parietal cells recovered to resting state.CONCOUSION: The acid secretion of parietal cells is consistent with their ultrastructural changes during the development and healing of stress ulcer induced by WRS and the degree of gastric mucosal lesions, suggesting gastric acid play an important role in the development of stress ulcer and is closely related with the recovery of gastric mucosal lesions induced by WRS.展开更多
A 69-year-old male with chronic lymphocytic leukemia presented with iron deficiency anemia and post-prandial abdominal fullness. Endoscopy showed a large polyp on a stalk, protruding through the pylorus into the duode...A 69-year-old male with chronic lymphocytic leukemia presented with iron deficiency anemia and post-prandial abdominal fullness. Endoscopy showed a large polyp on a stalk, protruding through the pylorus into the duodenum causing intermittent gastric outlet obstruction. While prolapsing gastric antral polyps are usually benign and hyperplastic, inflammatory or regenerative in type, excisional snare polypectomy here led to complete resolution of his symptoms, but showed a malignant polyp.展开更多
Gastric carcinoma remains a common disease worldwide with a dismal prognosis. Therefore, it represents a very important health problem. It occurs with a high incidence in Asia and is one of the leading causes of cance...Gastric carcinoma remains a common disease worldwide with a dismal prognosis. Therefore, it represents a very important health problem. It occurs with a high incidence in Asia and is one of the leading causes of cancer death in the world. Although the incidence and mortality of gastric carcinoma are decreasing in many countries,gastric cancer still represents the second most frequent malignancies in the world and the fourth in Europe. The 5-year survival rate of gastric carcinoma is low. The etiology and pathogenesis are not yet fully known. The study of gastric cancer is important in clinical medicine as well as in public health. Over the past 15 years,integrated research in molecular pathology has clarified the details of genetic and epigenetic abnormalities of cancer-related genes in the course of the development and progression of gastric cancer. Gastric cancer, as all cancers, is the end result of the interplay of many risk factors as well as protective factors. Although epidemiological evidence indicates that environmental factors play a major role in gastric carcinogenesis, the role of immunological, genetic, and immunogenetic factors are thought to contribute to the pathogenesis of gastric carcinoma. Among the environmental factors,diet and Helicobacter pylori are more amenable to intervention aimed at the prevention of gastric cancer.The aim of the present paper is to review and include the most recent published evidence to demonstrate that only a multidisciplinary approach will lead to the advancement of the pathogenesis and prevention of gastric cancer. On the immunogenetic research it is clear that evidence is accumulating to suggest that a genetic profile favoring the proinflammatory response increases the risk of gastric carcinoma.展开更多
TO THE EDITOR Sir, I read with great interest the recently published article in the World Journal of Gastroenterology by Jin and co-workers on the cloning and characterization of porcine aquaporin 1 water channel from...TO THE EDITOR Sir, I read with great interest the recently published article in the World Journal of Gastroenterology by Jin and co-workers on the cloning and characterization of porcine aquaporin 1 water channel from the pig liver and studies on its expression in the porcine gastrointestinal system. The authors should be congratulated for making this important and valuable contribution to the field of aquaporin biology and porcine gastrointestinal physiology. However, there are a number of unresolved issues and controversies concerning the expression of aquaporins (especially aquaporin 1) in the gastrointestinal system that are worthy of additional comment and discussion by Jin and co-workers.展开更多
AIM: To evaluate the efficacy of CT-maximum intensity projection (CT-MIP) in the detection of gastric varices and their infiowing and outflowing vessels in patients with gastric varices scheduled to undergo balloon...AIM: To evaluate the efficacy of CT-maximum intensity projection (CT-MIP) in the detection of gastric varices and their infiowing and outflowing vessels in patients with gastric varices scheduled to undergo balloonoccluded retrograde transvenous obliteration (B-RTO). METHODS: Sixteen patients with endoscopically confirmed gastric varices were included in this study. All patients were evaluated with CT-MIP using threedimensional reconstructions, before and after B-RTO. RESULTS: CT-MIP clearly depicted gastric varices in 16 patients (100%), the left gastric vein in 6 (32.5%), the posterior gastric vein in 12 (75.0%), the short gastric veins in 13 (81.3%), gastrorenal shunts in 16 (100%), the hemiazygos vein (HAZV) in 4 (25.0%), the pericardiophrenic vein (PCPV) in 9 (56.3%), and the left inferior phrenic vein in 9 patients (56.3%). Although flow direction itself cannot be determined from CT-MIP, this modality provided clear images of the inflowing and the outflowing vessels. Moreover, in one patient, short gastric veins were not seen on conventional angiographic portography images of the spleen, but were clearly revealed on CT-MIP. CONCLUSION: We suggest that CT-MIP should be considered as a routine method for detecting and diagnosing collateral veins in patients with gastric varices scheduled for B-RTO. Furthermore, CT-MIP is more useful than endoscopy in verifying the early therapeutic effects of B-RTO.展开更多
AIM: To investigate retrospectively the clinical and endoscopic features of bleeding Dieulafoy's lesions and to assess the short- and long-term effectiveness of endoscopic treatment.METHODS: Twenty-three patients ...AIM: To investigate retrospectively the clinical and endoscopic features of bleeding Dieulafoy's lesions and to assess the short- and long-term effectiveness of endoscopic treatment.METHODS: Twenty-three patients who had gastrointestinal bleeding from Dieulafoy's lesions underwent endoscopic therapy. Demographic data, mode of presentation, riskfactors for gastrointestinal bleeding, blood transfusion requirements, endoscopic findings, details of endoscopic therapy, recurrence of bleeding, and mortality rates were collected and analyzed retrospectively.RESULTS: Hemostasis was attempted by dextrose 50% plus epinephrine in 10 patients, hemoclipping in 8 patients,heater probe in 2 patients and ethanolamine oleate in 2 patients. Comorbid conditions were present in 17 patients (74%). Overall permanent hemostasis was achieved in 18 patients (78%). Initial hemostasis was successful with no recurrent bleeding in patients treated with hemoclipping, heater probe or ethanolamine injection. In the group of patients who received dextrose 50% plus epinephrine injection treatment, four (40%) had recurrent bleeding and one (10%) had unsuccessful initial hemostasis.Of the four patients who had rebleeding, three had unsuccessful hemostasis with similar treatment. Surgical treatment was required in five patients (22%) owing to uncontrolled bleeding, recurrent bleeding with unsuccessful retreatment and inability to approach the lesion. One patient (4.3%) died of sepsis after operation during hospitalization. There were no side-effects related to endoscopic therapy. None of the patients in whom permanent hemostasis was achieved presented with rebleeding from Dieulafoy's lesion over a mean long-term follow-up of 29.8 mo.CONCLUSION: Bleeding from Dieulafoy's lesions can be managed successfully by endoscopic methods, which should be regarded as the first choice. Endoscopic hemoclipping therapy is recommended for bleeding Dieulafoy's lesions.展开更多
AIM: To study the effects of indomethacin on the isolated transverse and longitudinal rat gastric fundus strips.METHODS: The strips were suspended in an organ bath containing oxygenated Krebs solution, and contractile...AIM: To study the effects of indomethacin on the isolated transverse and longitudinal rat gastric fundus strips.METHODS: The strips were suspended in an organ bath containing oxygenated Krebs solution, and contractile responses to electrical field stimulation were recorded on a physiograph in an isotonic manner after administration of cumulative concentrations of indomethacin. The effects of indomethacin on the strips pretreated with KATP channel modulators, diazoxide and glybenclamide were studied.RESULTS: Treatment of the transverse strips with indomethacin resulted in a concentration-dependent inhibitory response. In longitudinal strips, biphasic responses were seen, which included a stimulatory response at low concentrations of indomethacin, followed by an inhibitory response at higher concentrations.Diazoxide pre-treatment inhibited the stimulatory response of longitudinal strips. Glybenclamide pre-treatment not only blocked inhibitory effect of the low concentrations of indomethacin on transverse strips, but also increased the amplitude of contractions. Moreover, the drug decreased the amplitude of contractions in longitudinal strips.CONCLUSION: Responses of the isolated longitudinal and transverse rat gastric fundus strips to indomethacin are not similar, and are influenced by KATP channel modulators.展开更多
Several hundred species of bacteria inhabit the gut, and affect its cell biology, morphology and homeostasis. Many bacteria are however potential pathogens, especially if the integrity of the epithelial barrier is phy...Several hundred species of bacteria inhabit the gut, and affect its cell biology, morphology and homeostasis. Many bacteria are however potential pathogens, especially if the integrity of the epithelial barrier is physically or functionally breached. Conversely, the interaction between host and commensal microbes can confer important health benefits. This has led to commercial and public interest in 'probiotics', live microbes principally taken as food supplements. Might probiotics also be used in disease therapy? Experimental evidence that probiotics modulate gut physiology, particularly barrier integrity and immunological function, underpins exciting new gastroenterological research. We discuss below the scientific basis for probiotic effects and present a critical perspective for their use in relation to gastrointestinal disease.展开更多
文摘Esophageal and gastric cancers are both common and deadly. Patients present most often after disease progression and survival is therefore poor. Due to demographic variability and recent changes in disease incidence, much emphasis has been placed on studying risk factors for both esophageal and gastric cancers. However, with increasing understanding of these diseases, low survival rates persist and continued intensive studies are necessary to optimize treatment plans. This review article discusses updates in the evolving epidemiology, clinical presentation, risk factors, and diagnostic and treatment modalities of esophageal and gastric cancers.
文摘The incidence and mortality of gastric cancer have fallen dramatically in US and elsewhere over the past several decades. Nonetheless, gastric cancer remains a major public health issue as the fourth most common cancer and the second leading cause of cancer death worldwide. Demographic trends differ by tumor location and histology. While there has been a marked decline in distal, intestinal type gastric cancers, the incidence of proximal, diffuse type adenocarcinomas of the gastric cardia has been increasing, particularly in the Western countries. Incidence by tumor sub-site also varies widely based on geographic location, race, and socioeconomic status. Distal gastric cancer predominates in developing countries, among blacks, and in lower socioeconomic groups, whereas proximal tumors are more common in developed countries, among whites, and in higher socio-economic classes. Diverging trends in the incidence of gastric cancer by tumor location suggest that they may represent two diseases with different etiologies. The main risk factors for distal gastric cancer include Helicobacter pylori (H pylori) infection and dietary factors, whereas gastroesophageal reflux disease and obesity play important roles in the development of proximal stomach cancer. The purpose of this review is to examine the epidemiology and risk factors of gastric cancer, and to discuss strategies for primary prevention.
文摘AIM: To identify the clinicopathological characteristics of lymph node-negative gastric carcinoma, and also to evaluate outcome indicators in the lymph node-negative patients.METHODS: Of 2848 gastric carcinoma patients, 1524 (53.5%) were lymph nede-negative. A statistical analysis was performed using the Cox model to estimate outcome indicators. RESULTS: There was a significant difference in the recurrence rate between lymph nede-negative and lymph node-positive patients (14.4% vs 41.0%, P〈0.001). The 5-year survival rate was significantly lower in lymph node-positive than in lymph node-negative patients (31.1% vs 77.4%, P〈0.001). Univariate analysis revealed that the following factors influenced the 5-year survival rate: patient age, tumor size, depth of invasion, tumor location, operative type, and tumor stage at initial diagnosis. The Cox proportional hazard regression model revealed that tumor size, serosal invasion, and curability were independent, statistically significant, prognostic indicators of lymph node-negative gastric carcinoma. CONCLUSION: Lymph node-negative patients have a favorable outcome attributable to high curability, but the patients with relatively large tumors and serosal invasion have a poor prognosis. Curability is one of the most reliable predictors of long-term survival for lymph nodenegative gastric carcinoma patients.
基金Supported by the National Research Council Canada and the National Institutes of Health, United States
文摘The human gastrointestinal (GI) tract is colonized by non-pathogenic commensal microflora and frequently exposed to many pathogenic organisms. For the maintenance of GI homeostasis, the host must discriminate between pathogenic and non-pathogenic organisms and initiate effective and appropriate immune and inflammatory responses. Mammalian tolllike receptors (TLRs) are members of the patternrecognition receptor (PRR) family that plays a central role in the initiation of innate cellular immune responses and the subsequent adaptive immune responses to microbial pathogens. Recent studies have shown that gastrointestinal epithelial cells express almost all TLR subtypes characterized to date and that the expression and activation of TLRs in the GI tract are tightly and coordinately regulated. This review summarizes the current understanding of the crucial dual roles of TLRs in the development of host innate and adaptive immune responses to GI infections and the maintenance of the immune tolerance to commensal bacteria through downregulation of surface expression of TLRs in intestinal epithelial cells.
基金Supported by the Faculty of Medicine and Health Sciences Research Grant, UAE University, United Arab Emirates
文摘To investigate the effects of leptin (1-20μg/kg) on acidified ethanol (AE)- and indomethacin (Indo)-induced gastric lesions in rats and compare it with ranitidine, lansoprazole, and omeprazole and to determine its mechanisms of actions.METHODS: Gastric ulcers, which were approximately 1 mm in width, formed in the glandular portion of the gastric mucosa produced by oral administration of either AE or Indo were taken as ulcer index. The inhibitory effect of subcutaneous administration of leptin, two proton pump inhibitors (PPIs) lansoprazole and omeprazole, or H2-receptor antagonist ranitidine 30 min before AE or Indo was evaluated.A radioimmunoassay was used to determine the PGE2 concentration in the homogenate of the glandular portion of the stomach. We performed histological study of the glandular stomach for the evaluation of total, acidic, and sulfated mucus content.RESULTS: Subcutaneous administration of leptin, two PPI slansoprazole and omeprazole or H2-receptor antagonist ranitidine 30 min before AE or Indo produced a dosedependent and reproducible inhibition of gastric ulcers (GUs). This inhibition was found to be more potent than other antagonists used. In N^G-nitro L-arginine methyl ester (L-NAME)-pretreated animals, the ulcer prevention ability of leptin in AE-induced ulcer was significantly reduced,compared to rats without L-NAME pretreatment. However,the ulcer prevention ability of leptin was not altered by L-NAME treatment in Indo-induced ulcers. Leptin produced a dose-dependent increase in PGE2 level in the gastric glandular tissues. Leptin also increased mucus secretion.CONCLUSION: The results of the present study show that leptin inhibits GU formation by AE or Indo in a dosedependent and reproducible manner in rats. The results also suggest that leptin prevents ulcer formation by increasing the activities of the cyclo-oxygenase and/or nitric oxide pathways and by increasing mucus secretion.
文摘Bleeding from gastric varices has been successfully treated by endoscopic modalities. Once the bleeding from the gastric varices is stabilized, endoscopic treatment and/or interventional radiology should be performed to eradicate varices completely. Partial splenic artery embolization is a supplemental treatment to prolong the obliteration of the veins feeding and/or draining the varices. The overall incidence of bleeding from gastric varices is lower than that from esophageal varices. No studies to date have defi nitively characterized the causal factors behind bleeding from gastric varices. The initial episodes of bleeding from esophageal varices or gastric varices without prior treatment may be at least partly triggered by a violation of the mucosal barrier overlying varices. This is especially likely in the case of varices of the fundus. In view of the high rate of hemostasis achieved among bleeding gastric varices, treatment should be administered in selective cases. Among untreated cases, steps to prevent gastric mucosal injury confer very important protection against gastric variceal bleeding.
基金Supported by the Science and Technology Committee Foundation of Jiangsu Province, No. BS98028
文摘AIM: To investigate the microsatellite instability (MSI) in cancer and pre-cancerous lesions of the stomach and its mechanisms underlying the development of gastric cancer.METHODS: Thirty-six gastric cancer samples were obtained from patients undergoing surgery. Forty-one gastric mucosa samples with dysplasia and 51 with intestinal metaplasia (IM) were obtained from patients with chronic gastritis undergoing gastro-endoscopy. Genomic DNA was extracted from the samples. Silver staining single strand conformation polymorphis-polymerize chain reaction (SSCP-PCR) was used to screen MSI markers at 5 loci (Bat-25, Bat-26, D5S346, D17S250, and D2S123)in fresh tissues and formalin-fixed, paraffin-embedded samples and their corresponding normal gastric mucosa.RESULTS: The abnormal shifting of the single-strand DNA (MSI) was identified in 21 out of 36 (58.3%) gastric cancers.Seven cases showed high-level MSI (two or more loci altered) and 14 showed low-level MSI (one locus altered).Gastric cancer with MSI had a tendency to be located in the distal stomach. MSI was also detected in 11 out of 41(26.8%) dysplasia samples and in 9 of 51 (17.6%) IM samples respectively. Three cases of dysplasia and one case of IM showed high-level MSI. Eight cases of dysplasia and 8 cases of IM displayed low-level MSI. MIS in IM was found only in moderate or severe-grade IM. No association was detected between MSI and dysplasia grade.CONCLUSION: Accumulation of MSI in dysplasia and intestinal metaplasia of gastric mucosa may be an early molecular event during gastric carcinogenesis and may contribute to the acquisition of transformed cell phenotype and the development of gastric cancer.
文摘Metastatic breast cancer involving the hepatobiliary tract or ascites secondary to peritoneal carcinomatosis has been well described. Luminal gastrointestinal tract involvement is less common and recognition of the range of possible presentations is important for early and accurate diagnosis and treatment. We report 6 patients with a variety of presentations of metastatic breast cancer of the luminal gastrointestinal tract. These include oropharyngeal and esophageal involvement presenting as dysphagia with one case of pseudoachalasia, a linitis plastica-like picture with gastric narrowing and thickened folds, small bowel obstruction and multiple strictures mimicking Crohn’s disease, and a colonic neoplasm presenting with obstruction. Lobular carcinoma, representing only 10% of breast cancers is more likely to metastasize to the gastrointestinal tract. These patients presented with gastrointestinal manifestations after an average of 9.5 years and as long as 20 years from initial diagnosis of breast cancer. Given the increased survival of breast cancer patients with current therapeutic regimes, more unusual presentations of metastatic disease, including involvement of the gastrointestinal tract can be anticipated.
基金Supported by the Key Project of Military Medicine during the 10th five-year Plan period, PLA, China, No. 01Z059
文摘AIM: To investigate the dynamic functional and ultrastructural changes of gastric parietal cells induced by water immersion-restraint stress (WRS) in rats.METHODS: WRS model of Sprague-Dawley (SD) rats was established. Fifty-six male SD rats were randomly divided into control group, stress group and post-stress group. The stress group was divided into 1, 2 and 4 h stress subgroups. The post-stress group was divided into 24, 48 and 72 h subgroups. The pH value of gastric juice, ulcer index (UI) of gastric mucosa and H^+, K^+- ATPase activity of gastric parietal cells were measured. Ultrastructural change of parietal cells was observed under transmission electron microscope (TEM).RESULTS: The pH value of gastric juice decreased time-dependently in stress group and increased in post-stress group. The H^+, K^+-ATPase activity of gastric parietal cells and the UI of gastric mucosa increased time-dependently in stress group and decreased in poststress group. Compared to control group, the pH value decreased remarkably (P = 0.0001), the UI and H^+, K^+- ATPase activity increased significantly (P = 0.0001, P = 0.0174) in 4 h stress subgroup. UI was positively related with stress time (r = 0.9876, P 〈 0.01) but negatively with pH value (r = -0.8724, P 〈 0.05). The parietal cells became active in stress group, especially in 4 h stress subgroup, in which plenty of intracellular canalicular and mitochondria were observed under TEM. In post-stress group, the parietal cells recovered to resting state.CONCOUSION: The acid secretion of parietal cells is consistent with their ultrastructural changes during the development and healing of stress ulcer induced by WRS and the degree of gastric mucosal lesions, suggesting gastric acid play an important role in the development of stress ulcer and is closely related with the recovery of gastric mucosal lesions induced by WRS.
文摘A 69-year-old male with chronic lymphocytic leukemia presented with iron deficiency anemia and post-prandial abdominal fullness. Endoscopy showed a large polyp on a stalk, protruding through the pylorus into the duodenum causing intermittent gastric outlet obstruction. While prolapsing gastric antral polyps are usually benign and hyperplastic, inflammatory or regenerative in type, excisional snare polypectomy here led to complete resolution of his symptoms, but showed a malignant polyp.
基金Supported by the Foundation of Immunogenetics and Cluster I of VU University Medical Center, Amsterdam
文摘Gastric carcinoma remains a common disease worldwide with a dismal prognosis. Therefore, it represents a very important health problem. It occurs with a high incidence in Asia and is one of the leading causes of cancer death in the world. Although the incidence and mortality of gastric carcinoma are decreasing in many countries,gastric cancer still represents the second most frequent malignancies in the world and the fourth in Europe. The 5-year survival rate of gastric carcinoma is low. The etiology and pathogenesis are not yet fully known. The study of gastric cancer is important in clinical medicine as well as in public health. Over the past 15 years,integrated research in molecular pathology has clarified the details of genetic and epigenetic abnormalities of cancer-related genes in the course of the development and progression of gastric cancer. Gastric cancer, as all cancers, is the end result of the interplay of many risk factors as well as protective factors. Although epidemiological evidence indicates that environmental factors play a major role in gastric carcinogenesis, the role of immunological, genetic, and immunogenetic factors are thought to contribute to the pathogenesis of gastric carcinoma. Among the environmental factors,diet and Helicobacter pylori are more amenable to intervention aimed at the prevention of gastric cancer.The aim of the present paper is to review and include the most recent published evidence to demonstrate that only a multidisciplinary approach will lead to the advancement of the pathogenesis and prevention of gastric cancer. On the immunogenetic research it is clear that evidence is accumulating to suggest that a genetic profile favoring the proinflammatory response increases the risk of gastric carcinoma.
文摘TO THE EDITOR Sir, I read with great interest the recently published article in the World Journal of Gastroenterology by Jin and co-workers on the cloning and characterization of porcine aquaporin 1 water channel from the pig liver and studies on its expression in the porcine gastrointestinal system. The authors should be congratulated for making this important and valuable contribution to the field of aquaporin biology and porcine gastrointestinal physiology. However, there are a number of unresolved issues and controversies concerning the expression of aquaporins (especially aquaporin 1) in the gastrointestinal system that are worthy of additional comment and discussion by Jin and co-workers.
文摘AIM: To evaluate the efficacy of CT-maximum intensity projection (CT-MIP) in the detection of gastric varices and their infiowing and outflowing vessels in patients with gastric varices scheduled to undergo balloonoccluded retrograde transvenous obliteration (B-RTO). METHODS: Sixteen patients with endoscopically confirmed gastric varices were included in this study. All patients were evaluated with CT-MIP using threedimensional reconstructions, before and after B-RTO. RESULTS: CT-MIP clearly depicted gastric varices in 16 patients (100%), the left gastric vein in 6 (32.5%), the posterior gastric vein in 12 (75.0%), the short gastric veins in 13 (81.3%), gastrorenal shunts in 16 (100%), the hemiazygos vein (HAZV) in 4 (25.0%), the pericardiophrenic vein (PCPV) in 9 (56.3%), and the left inferior phrenic vein in 9 patients (56.3%). Although flow direction itself cannot be determined from CT-MIP, this modality provided clear images of the inflowing and the outflowing vessels. Moreover, in one patient, short gastric veins were not seen on conventional angiographic portography images of the spleen, but were clearly revealed on CT-MIP. CONCLUSION: We suggest that CT-MIP should be considered as a routine method for detecting and diagnosing collateral veins in patients with gastric varices scheduled for B-RTO. Furthermore, CT-MIP is more useful than endoscopy in verifying the early therapeutic effects of B-RTO.
文摘AIM: To investigate retrospectively the clinical and endoscopic features of bleeding Dieulafoy's lesions and to assess the short- and long-term effectiveness of endoscopic treatment.METHODS: Twenty-three patients who had gastrointestinal bleeding from Dieulafoy's lesions underwent endoscopic therapy. Demographic data, mode of presentation, riskfactors for gastrointestinal bleeding, blood transfusion requirements, endoscopic findings, details of endoscopic therapy, recurrence of bleeding, and mortality rates were collected and analyzed retrospectively.RESULTS: Hemostasis was attempted by dextrose 50% plus epinephrine in 10 patients, hemoclipping in 8 patients,heater probe in 2 patients and ethanolamine oleate in 2 patients. Comorbid conditions were present in 17 patients (74%). Overall permanent hemostasis was achieved in 18 patients (78%). Initial hemostasis was successful with no recurrent bleeding in patients treated with hemoclipping, heater probe or ethanolamine injection. In the group of patients who received dextrose 50% plus epinephrine injection treatment, four (40%) had recurrent bleeding and one (10%) had unsuccessful initial hemostasis.Of the four patients who had rebleeding, three had unsuccessful hemostasis with similar treatment. Surgical treatment was required in five patients (22%) owing to uncontrolled bleeding, recurrent bleeding with unsuccessful retreatment and inability to approach the lesion. One patient (4.3%) died of sepsis after operation during hospitalization. There were no side-effects related to endoscopic therapy. None of the patients in whom permanent hemostasis was achieved presented with rebleeding from Dieulafoy's lesion over a mean long-term follow-up of 29.8 mo.CONCLUSION: Bleeding from Dieulafoy's lesions can be managed successfully by endoscopic methods, which should be regarded as the first choice. Endoscopic hemoclipping therapy is recommended for bleeding Dieulafoy's lesions.
文摘AIM: To study the effects of indomethacin on the isolated transverse and longitudinal rat gastric fundus strips.METHODS: The strips were suspended in an organ bath containing oxygenated Krebs solution, and contractile responses to electrical field stimulation were recorded on a physiograph in an isotonic manner after administration of cumulative concentrations of indomethacin. The effects of indomethacin on the strips pretreated with KATP channel modulators, diazoxide and glybenclamide were studied.RESULTS: Treatment of the transverse strips with indomethacin resulted in a concentration-dependent inhibitory response. In longitudinal strips, biphasic responses were seen, which included a stimulatory response at low concentrations of indomethacin, followed by an inhibitory response at higher concentrations.Diazoxide pre-treatment inhibited the stimulatory response of longitudinal strips. Glybenclamide pre-treatment not only blocked inhibitory effect of the low concentrations of indomethacin on transverse strips, but also increased the amplitude of contractions. Moreover, the drug decreased the amplitude of contractions in longitudinal strips.CONCLUSION: Responses of the isolated longitudinal and transverse rat gastric fundus strips to indomethacin are not similar, and are influenced by KATP channel modulators.
文摘Several hundred species of bacteria inhabit the gut, and affect its cell biology, morphology and homeostasis. Many bacteria are however potential pathogens, especially if the integrity of the epithelial barrier is physically or functionally breached. Conversely, the interaction between host and commensal microbes can confer important health benefits. This has led to commercial and public interest in 'probiotics', live microbes principally taken as food supplements. Might probiotics also be used in disease therapy? Experimental evidence that probiotics modulate gut physiology, particularly barrier integrity and immunological function, underpins exciting new gastroenterological research. We discuss below the scientific basis for probiotic effects and present a critical perspective for their use in relation to gastrointestinal disease.