In Singapore, the highest incidence of gastric cancer occurs in the Chinese (C), with lower rates among Malay (M) and Indian (I) subjects. The purpose of the present paper was to examine whether racial differences in the prevalence of Helicobacter pylori and serum pepsinogen (PG) could account for this difference.
Helicobacter pylori CagA modifies the signalling of host cells and causes gastric diseases. Although CagA is injected into gastric epithelial cells through the type IV secretion machinery, it remains unclear how CagA is transported towards the machinery in the bacterial cytoplasm. In this study, it was determined that the proton-dependent intracytoplasmic transport system correlates with the priming of CagA secretion from H. pylori. The cytotoxicity of neutral-pH- and acidic-pH-treated H. pylori was examined in the AGS cell line. The amount of phosphorylated CagA in AGS cells incubated with acidic-pH- and neutral-pH-treated H. pylori was determined by enzyme immunoassay and Western blot. The production of CagA and adherence of the treated bacteria were examined by enzyme immunoassay and light microscopy, respectively. To clarify how CagA is transported towards the inner membrane of the treated bacteria, the localization of CagA was analysed by immunoelectron microscopy. The proportion of hummingbird cells in the AGS cell line rapidly increased following the inoculation of acidic-pH-treated H. pylori but increased more slowly with neutral-pH-treated H. pylori, and the phenomenon correlated with the amount of phosphorylated CagA in AGS cells. CagA was densely localized near the inner membrane in the acidic-pH-treated bacterial cytoplasm, but this localization was not observed in the neutral-pH-treated bacterial cytoplasm, suggesting that CagA shifts from the centre to the peripheral portion of the cytoplasm as a result of an extracellular decrease in pH. This phenomenon depended on the presence of UreI, a proton-dependent urea channel, but not on the presence of urea. The pH treatments did not enhance CagA production or the adherence of the bacterium to AGS cells. The authors propose that H. pylori possesses a proton-dependent intracytoplasmic transport system that probably accelerates priming for CagA injection.
Rats exposed to stress developed various changes in the gastrointestinal tract and hormones. The present study was designed to compare the impact of tocopherol and tocotrienol on changes that influence gastric and hormonal parameters important in maintaining gastric mucosal integrity in rats exposed to restrain stress. These include gastric acidity, gastric tissue content of parameters such as malondialdehyde, prostaglandin (PGE(2)), serum levels of gastrin and glucagon-like peptide-1 (GLP-1). Sixty male Sprague-Dawley rats (200-250 g) were randomly divided into three equal sized groups, a control group which received a normal rat diet (RC) and two treatment groups each receiving a vitamin deficient diet with oral supplementation of either tocopherol (TF) or tocotrienol (TT) at 60 mg/kg body weight. Blood samples were taken from half the number of rats (non-stressed group) after a treatment period of 28 days before they were killed. The remaining half was subjected to experimental restraint-stress, at 2 hours daily for 4 consecutive days (stressed groups), on the fourth day, blood samples were taken and the rats killed. The findings showed that the gastric acid concentration and serum gastrin level in stressed rats were significantly (P<0.05) reduced compared to the non-stressed rats in the control and TF groups. However, the gastric acidity and gastrin levels in the TT group were comparable in stressed and non-stressed rats. These findings suggest that tocotrienol is able to preserve the gastric acidity and serum gastrin level which are usually altered in stressed conditions. The PGE(2) content and the plasma GLP-1 level were, however, comparable in all stressed and non-stressed groups indicating that these parameters were not altered in stress and that supplementation with TF or TT had no effect on the gastric PGE2 content or the GLP-1 level. The malondialdehyde, an indicator of lipid peroxidation was higher from gastric tissues in the stressed groups compared to the non-stressed groups. These findings implicated that free radicals may play a role in the development of gastric injury in stress and supplementation with either TF or TT was able to reduce the lipid peroxidation levels compared to the control rats. We conclude that both tocopherol and tocotrienol are comparable in their gastro-protective ability against damage by free radicals generated in stress conditions, but only tocotrienol has the ability to block the stress-induced changes in the gastric acidity and gastrin level.
Lesions associated with two species of tapeworms within the digestive tract of wild-caught specimens of the bull shark, Carcharhinus leucas, and the sicklefin weasel shark, Hemigaleus microstoma, from Malaysian Borneo are described. Portions of the glandular stomach and pyloric gut with parasites were removed and fixed in 10% formalin buffered in sea water. Whole mounts, histological sections of tissues with and without worms in situ, and scanning electron microscopy images of detached worms were examined. Both species of cestodes belonged to the trypanorhynch family Tentaculariidae. Heteronybelinia estigmena was found in large numbers parasitizing the pyloric gut of C. leucas; an unidentified tentaculariid was found in relatively small numbers in both the glandular stomach and pyloric gut of H. microstoma. Both species burrowed their scoleces deeply in the mucosa and attached via hooked tentacles and unciniform microtriches of the scolex. The lesions induced by the parasites were marked in both sharks and ranged from acute necrotizing to chronic granulomatous gastroenteritis. Regenerative hyperplasia and intestinal metaplasia of gastric epithelium were also present. The severity and character of pathology was causally linked to the intensity of infection, the attachment mode of the parasites, and to the anatomophysiological relationships within the gut of the host shark.
In recent years, infection of the stomach with the organism Helicobacter Pylori has been found to be the main cause of gastric ulcers, one of the common ailments afflicting humans. Excessive acid secretion in the stomach, reduction in gastric mucosal blood flow, constant intake of non-steroid anti-inflammatory drugs (NSAIDS), ethanol, smoking, stress etc. are also considered responsible for ulcer formation. The prevalent notion among sections of population in this country and perhaps in others is that "red pepper" popularly known as "Chilli," a common spice consumed in excessive amounts leads to "gastric ulcers" in view of its irritant and likely acid secreting nature. Persons with ulcers are advised either to limit or avoid its use. However, investigations carried out in recent years have revealed that chilli or its active principle "capsaicin" is not the cause for ulcer formation but a "benefactor." Capsaicin does not stimulate but inhibits acid secretion, stimulates alkali, mucus secretions and particularly gastric mucosal blood flow which help in prevention and healing of ulcers. Capsaicin acts by stimulating afferent neurons in the stomach and signals for protection against injury causing agents. Epidemiologic surveys in Singapore have shown that gastric ulcers are three times more common in the "Chinese" than among Malaysians and Indians who are in the habit of consuming more chillis. Ulcers are common among people who are in the habit of taking NSAIDS and are infected with the organism "Helicobacter Pylori," responsible for excessive acid secretion and erosion of the mucosal layer. Eradication of the bacteria by antibiotic treatment and avoiding the NSAIDS eliminates ulcers and restores normal acid secretion.
Six groups of adult Sprague-Dawley rats were orally administered with a variety of treatments to elucidate their cytoprotective effects. Absolute ethanol combined with HCl was used to induce gastric lesions in rats. Aqueous and ethanol extracts of Chromolaena odorata, a famous folk herb for treating skin wounds were evaluated to determine their protective effect on gastric mucosa. In this study, aqueous extract and ethanol extract of C. odorata were combined with honey. In addition, honey alone and honey combined with cimetidine were also evaluated. Rat stomachs were examined grossly and histologically. Results were expressed as inhibition percentage. The honey and aqueous extract combination showed the highest inhibition percentage (72.67%) followed by honey and ethanol extract (58.92%), honey and cimetidine (56.55%) and the lowest was honey alone (46.74%). However, there were no significant differences between the effects of aqueous and ethanol extracts of C. odorata and honey in promoting cytoprotective effects and this may be due to the small sample size. Nevertheless, these results suggest that C. odorata and honey may be beneficial in treating induced gastric mucosal injury.
The new millennium has seen distinct changes in the pattern of gastrointestinal disease in the Asia-Pacific region. These changes are important as more than half of the world's population come from the region and therefore impact significantly on the global disease burden. The highest incidence of gastric cancer (GCA) has been reported from Asia and GCA remains a very important cancer. However time-trend studies have shown a decrease in GCA incidence in several countries in Asia. A rise in cardio-esophageal cancers as seen in the West has not been reported. On the other hand, colorectal cancer has been steadily increasing in Asia with age-standardized incidence rates of some countries approaching that of the West. The pattern of acid-related diseases has also changed. Gastroesophageal reflux disease is a fast emerging disease with an increasing prevalence of reflux esophagitis and reflux symptoms. The prevalence of peptic ulcer disease has at the same time declined in step with a decrease in H. pylori infection. Many of the changes taking place mirror the Western experience of several decades ago. Astute observation of the epidemiology of emerging diseases combined with good scientific work will allow a clearer understanding of the key processes underlying these changes. With rapid modernization, lifestyle changes have been blamed for an increase in several diseases including gastroesophageal reflux disease, nonalcoholic fatty liver disease and colorectal cancer. A worrying trend has been the increase in obesity among Asians, which has been associated with an increase in metabolic diseases and various gastrointestinal cancers. Conversely, an improvement in living conditions has been closely linked to the decrease in GCA and H. pylori prevalence.
Gastric cancer is one of the most common cancers and most frequent causes of cancer-related deaths in the world. The overall survival rate is 15-20%. Although the incidence is declining, its prognosis remains poor. The etiological factors and pathogenesis of gastric cancer are not yet fully understood. The integrated research in molecular pathology clarified the details of genetic and epigenetic abnormalities of cancer-related genes in the course of development and progression of gastric cancer. Although epidemiological evidences indicate that environmental factors play a major role in the carcinogenesis, the role of immunological, genetic and immunogenetic factors are thought to contribute to etiopathogenesis of gastric carcinoma. In addition to better understanding of pathogenesis of gastric cancer, the incidence, diagnostic studies and the therapeutic options have also undergone important changes in the last decade. There is ongoing debate regarding the role of adjuvant treatment. In advanced disease, palliation of symptoms, rather than cure, is the primary goal of patient management. Several combination therapies have been developed and have been examined in phase III trials; however, in most cases, they have failed to demonstrate a survival advantage over the reference arm. This review summarizes the newer concepts of molecular biology on gastric carcinogenesis and the new important recommendations for the management of patient with gastric carcinoma.
The great variability in gastric cancer rates across Asia, with very high incidences in Japan and Korea, and exceedingly low incidences in ethnic Malays, whether in Malaysia or Indonesia, appears largely due to variation in Helicobacter pylori infection rates. While between 2% and 10.6% of gastric cancers in a recent Japanese survey were considered to be negative for bacterial infection on the basis of seropositivity and H. pylori-dependent mucosal atrophy, it is notoriously difficult to preclude past infection. The situation is greatly complicated by reported differences in the etiology of gastric cardia and non-cardia cancers. In the Western world there do appear to be tumours arising close to the esophageal-gastric junction which are not related to H. pylori and associated inflammation, but in most Asian populations these appear to be very rare. Therefore preventive efforts, and particularly screening, should be focused on markers of bacterial infection, with avoidance of unnecessary exposure to X-ray radiation.
Synchronous tumors are well documented in the gastrointestinal tract. Various combinations have been studied. There are a few studies, which highlight the incidental finding of the yellow beauty-the "carcinoid" of the duodenum simultaneously occurring with the venomous "diffuse gastric adenocarcinoma". This is a report one such case in a 58 year-old man, who unfortunately died on the 4th postoperative day due to cardiopulmonary arrest.
Background: (13) C – urea breath test (UBT) is sensitive and specific for detection of Helicobacter pylori (H. pylori) infection. Gastric biopsy culture for H. pylori confirms the diagnosis. Here, we analyzed data of all patients who were investigated for H. pylori infection using both tests throughout the year 2005. Materials and Methods : Retrospective data of 377 patients between the ages of 17 – 88 were identified through endoscopy records from January to December 2005. Upper endoscopy, UBT and gastric biopsy culture were performed on all patients simultaneously during each endoscopy session. Patients who had positive UBT and biopsy culture for H. pylori were treated with triple therapy of PPI, amoxicillin and clarithromycin for one week. A repeat of UBT was done at one-month post therapy. Results and Analysis: Twenty-eight patients on the list had no available data on UBT and were omitted from the analysis. Ethnic group Chinese comprised of 45.4% (n=163), followed by Malay, 37.3% (n=134), Indian, 10.6% (n=38) and others, 3.9% (n=14). UBT was positive in 23.7% (n=85)(figure1). H. pylori culture was positive in 19.2% (n=69)(figure1). Sixteen patients with UBT positive had H. pylori culture negative, 18.8% (n=16/85)(figure2). Five patients with H. pylori culture positive had UBT negative, 7.2% (n=5/69)(figure3). Ethnic group Indian had the highest incidence of UBT positive, 47.4% (n=18/38), followed by Others (Sikhs and foreigners) 42.8% (n=6/14), the Chinese 27.6% (n=45/163) and the Malays 11.6% (n= 16/138). UBT positive was the highest in the age group of 50 and above, 64.7% (n=55/85), followed by the age group between 30 to 49, 21.2% (n=18/85) and the age group of 29 and below, 14.5% (n=12/85). Out of the 85 UBT positive patients 91.8% (n=78/85)(figure4) of them responded to the conventional one week of triple therapy (PPI, amoxicillin, clarithromycin) with negative UBT at one-month post therapy compared to only 8.2% (n=7/85)(figure4) who failed with positive UBT at one-month post therapy.
Cryptosporidium fragile sp. n. (Apicomplexa) is described from black-spined toads, Duttaphrynus melanostictus (Schneider) (Amphibia, Anura, Bufonidae) from the Malay Peninsula. The parasitized animals were directly imported from Malaysia and harboured C. fragile at the time of arrival. Oocysts were subspherical to elliptical with irregular contour in optical section, measuring 6.2 (5.5-7.0) x 5.5 (5.0-6.5) microm. Oocyst wall was smooth and colourless in light microscopy. The endogenous development of C. fragile in the stomach of black-spined toad was analysed in detail using light and electron microscopy. Cryptosporidian developmental stages were confined to the surface of gastric epithelial cells. In transmission experiments, C. fragile has not been infective for one fish species, four amphibian species, one species of reptile and SCID mice. Full length small subunit rRNA gene sequence was obtained. Phylogenetic reconstruction revealed distinct status of C. fragile within the clade of species with gastric localisation including Cryptosporidium muris Tyzzer, 1907, Cryptosporidium serpentis Levine, 1980 and Cryptosporidium andersoni Lindsay, Upton, Owens, Morgan, Mead et Blagburn, 2000. Described characteristics differentiate C. fragile from the currently recognized Cryptosporidium species. Our experience with the description of C. fragile has led us to revise the recommended criteria for an introduction of a new Cryptosporidium species name. C. fragile is the first species described and named from an amphibian host. Its prevalence of 83% (15/18) in black-spined toads within the 3 months after importation calls for strict quarantine measures and import regulation for lower vertebrates.
The effects of Carica papaya leaf (CPL) aqueous extract on alcohol induced acute gastric damage and the immediate blood oxidative stress level were studied in rats. The results showed that gastric ulcer index was significantly reduced in rats pretreated with CPL extract as compared with alcohol treated controls. The in vitro studies using 2,2-Diphenyl-1-Picryl-Hydrazyl (DPPH) assay showed strong antioxidant nature of CPL extract. Biochemical analysis indicated that the acute alcohol induced damage is reflected in the alterations of blood oxidative indices and CPL extract offered some protection with reduction in plasma lipid peroxidation level and increased erythrocyte glutathione peroxidase activity. Carica papaya leaf may potentially serve as a good therapeutic agent for protection against gastric ulcer and oxidative stress.
Matched MeSH terms: Stomach Ulcer/chemically induced; Stomach Ulcer/prevention & control
Peritoneal anomalies are common in humans. We report the presence of a cystogastrocolic fold associated with an abnormally small gallbladder in a 50-year-old male cadaver. Presence of this fold is one of the clinically important anomalies, which can result in atrophy of the gallbladder or congenital obstruction of the duodenum.
As in developed societies, the prevalence of Helicobacter pylori has declined rapidly in Asia. This has been shown in both seroprevalence-based and endoscopy-based studies. While the decline in the incidence of gastric cancer has now been observed, a decrease in peptic ulcer disease has not been so clearly evident. This apparent paradox can be explained by an increase in non-H. pylori associated ulcers - such as those related to non-steroidal anti-inflammatory drugs or idiopathic ulcers. The increase of gastroesophageal reflux disease in Asia has been widely observed and commented on and its relationship to the decline in H. pylori speculated upon. However there have been few conclusive studies from Asia on this subject. While the improved diagnosis and elimination of H. pylori has contributed to its decline, a more basic change involving large segments of the Asian population must be responsible. An improvement in hygiene and living conditions that results from more affluent Asian societies is thought to be a possible cause.
This study investigates the effects of tocotrienol (TT) or alpha-tocopherol (TF) supplementation on corticosterone level, noradrenalin level and gastric lesions in rats exposed to restraint stress. Twenty-four male Sprague Dawley rats were randomly assigned into 4 equally sized groups; two control groups were given olive oil, while the treated group was supplemented with either tocotrienol of tocopherol orally at a dose of 60 mg/kg body weight. After 28 days of treatment, one control group, TT group and TF group were subjected to restraint stress, 2 hours daily for 4 consecutive days. After the last exposure to stress, plasma samples were taken to determine the corticosterone and noradrenalin levels, after which the rats were sacrificed. The stomach was excised for the evaluation of gastric lesions. Our findings showed that TT and TF were able to maintain the corticosterone level to the prestress values, while only TT was able to maintain the noradrenalin level in rats exposed to stress. Tocotrienol was found to be better in preventing formation of gastric lesions compared to TF. As a conclusion, the protective effect of vitamin E was related to the ability to inhibit stress induced elevation of corticosterone and noradrenalin levels.
HeIicobacter pylori infection rate was determined in 697 consecutive patients with ulcer, gastritis, duodenitis and non-ulcer dyspepsia by endoscopy at a Malaysian hospital in 1999-2002. Biopsies of the gastric antrum and body were subjected to the urease test, Gram staining of impression smears and culture examination. Infection was defined as a positive result in at least one test. The infection rates were 32.1, 10.4, 20.0 and 16.2% in ulcer, gastritis, duodenitis and non-ulcer dyspepsia patients, respectively. Overall, the prevalence of H. pylori infection was 14.6%, with the rate among the Indian (21.7%), Chinese (19.2%) and Bangladeshi foreign worker (23.1%) groups significantly higher (P<0.05) than that of the Malays (5.8%). Generally, the prevalence rate among males (18.9%) was significantly higher (P<0.001) than that among females (9.0%), but for a particular ethnic group, such trend and significant differences (P<0.05) were observed only among the Malays. In terms of gender, the prevalence rates of Malay males and females were also significantly lower (P<0.05) than those of Chinese and Indians. In conclusion, there is a significant difference in H. pylori infection prevalence rates among ethnic groups (highest in Indians, then Chinese and unusually low in Malays) and gender groups (highest in males) in Malaysia.