985 resultados para Gastric Mucosa -- microbiology
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The presence of an RNA virus in a South American subgenus of the Leishmania parasite, L. (Viannia), was detected several decades ago but its role in leishmanial virulence and metastasis was only recently described. In Leishmania guyanensis, the nucleic acid of Leishmania RNA virus (LRV1) acts as a potent innate immunogen, eliciting a hyper-inflammatory immune response through toll-like receptor 3 (TLR3). The resultant inflammatory cascade has been shown to increase disease severity, parasite persistence, and perhaps even resistance to anti-leishmanial drugs. Curiously, LRVs were found mostly in clinical isolates prone to infectious metastasis in both their human source and experimental animal model, suggesting an association between the viral hyperpathogen and metastatic complications such as mucocutaneous leishmaniasis (MCL). MCL presents as chronic secondary lesions in the mucosa of the mouth and nose, debilitatingly inflamed and notoriously refractory to treatment. Immunologically, this outcome has many of the same hallmarks associated with the reaction to LRV: production of type 1 interferons, bias toward a chronic Th1 inflammatory state and an impaired ability of host cells to eliminate parasites through oxidative stress. More intriguing, is that the risk of developing MCL is found almost exclusively in infections of the L. (Viannia) subtype, further indication that leishmanial metastasis is caused, at least in part, by a parasitic component. LRV present in this subgenus may contribute to the destructive inflammation of metastatic disease either by acting in concert with other intrinsic "metastatic factors" or by independently preying on host TLR3 hypersensitivity. Because LRV amplifies parasite virulence, its presence may provide a unique target for diagnostic and clinical intervention of metastatic leishmaniasis. Taking examples from other members of the Totiviridae virus family, this paper reviews the benefits and costs of endosymbiosis, specifically for the maintenance of LRV infection in Leishmania parasites, which is often at the expense of its human host.
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PURPOSE OF REVIEW: Many chemotherapeutic drugs, including fluoropyrimidines, platinums, CPT-11, taxanes and adriamycin have single-agent activity in advanced gastric cancer. Although combination chemotherapy has been shown to be more effective than single agents, response rates between 30 and 50% have not fulfilled their promise as progression-free survival from the best combinations ranges between 3 and 7 months and overall survival between 8 and 11 months. The development of targeted therapies in gastric cancer clearly stays behind the integration of these novel agents into new treatment concepts for patients with colorectal cancer. This review summarizes the experience and major recent advances in the development of targeted therapies in advanced gastric cancer. RECENT FINDINGS: Recent publications on targeted therapies in gastric cancer are limited to nonrandomized phase I or II trials. The majority of agents tested were angiogenesis inhibitors or agents targeting the epidermal growth factor receptors epidermal growth factor receptor 1 and HER2. SUMMARY: Adequately powered, randomized phase III trials are necessary to define the clinical role of targeted therapies in advanced gastric cancer. Biomarker studies to correlate with treatment outcomes will be critical to identify patients who benefit most from chemotherapy and targeted therapy.
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In a randomised trial comparing early enteral feeding by gastric and post-pyloric routes, White and colleagues have shown that gastric feeding is possible and efficient in the vast majority of critically ill patients. But the authors' conclusion that gastric is equivalent to post-pyloric is true in only the least severe patients. Given the extra workload and costs, post-pyloric is now clearly indicated in case of gastric feeding failure.
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Carcinoembryonic antigen (CEA) was identified in perchloric acid (PCA)_extract from normal colon mucosa by 2 immunological criteria: a line of identity in double diffusion and a parallel inhibition curve in radioimmunoassay (RIA), both with reference colon carcinoma-CEA (CEA-Tu). The average concentration of CEA in normal colon mucosa (CEA-No) was 35 times lower than in primary large bowel carcinomas and 230 times lower than in metastatic colon or rectum carcinomas. CEA-No was purified from PCA extracts of normal colon mucosa by Sephadex G-200 filtration and immunoadsorbent columns. Purified CEA-No had quatitatively the same inhibition activity in RIA as the British Standard CEA coded 73/601. Purified CEA-No was labelled with 125I. The percentage of binding of labelled CEA-No to a specific goat anti-CEA-Tu antiserum was similar to that of CEA-Tu. Labelled CEA-No could be used as radioactive tracer in RIA as well as labelled CEA-Tu. The physico-chemical properties of purified CEA-Tu as demonstrated by Sepharose 6 B filtration, SDS Polyacrylamide gel analysis and cesium chloride density gradient, were found to be almost identical to those of reference CEA-Tu. Preliminary results showed that CEA-No and CEA-Tu contained the same types of carbohydrates in similar proportions. A rabbit antiserum against CEA-No was obtained which demonstrated the same specificity as conventional anti-CEA-Tu antisera.
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We report here the case of a 55 year old female that underwent surgery for a well differentiated squamous cell carcinoma of the esophagus (middle third). Four months after surgery, she complains of neck pain, for which she is prescribed non steroidal antiinflammatory drugs (NSAID). A CT-scan and a Barium swallow are then normal. After three weeks of treatment, the patient is admitted on emergency to the Intensive Care Unit for a resuscitation hematemesis and atrial fibrillation with a fast ventricular response. The symptoms are stabilized after the transfusion of a few packed red blood cells. A few hours later, however, a massive hematemesis recurs and the patient dies despite intense resuscitation measures. Autopsy reveals three gastric ulcers, one of which had perforated through the cardiac left ventricular wall
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We have investigated in vitro, the effects of glucagon-like peptide-1-(7-36) amide (GLP-1-(7-36) amide), oxyntomodulin and glucagon on two rabbit parietal cell-enriched fractions (F3, F3n), with parietal cell contents of 60% and 88%, respectively. Histamine (10(-5) M) stimulated [14C]aminopyrine accumulation to an amount of 850% in excess of the basal level, whereas GLP-1-(7-36) amide (10(-7) M) and oxyntomodulin (10(-6) M) induced increases of 50% and 30%, respectively. With a histamine concentration of 10(-6) M, [14C]aminopyrine accumulation was stimulated to 498% in excess of the basal level; GLP-1-(7-36) amide (10(-7) M) and oxyntomodulin (10(-7) M) induced increases of 18% and 15%, respectively. With these parameters, oxyntomodulin[19-37] and glucagon were without effect. Specific binding of [125I]GLP-1-(7-36) amide to parietal cell plasma membranes was inhibited dose-dependently by GLP-1-(7-36) amide, oxyntomodulin and glucagon with inhibitory concentrations of 0.25 nM, 65 nM and 800 nM, respectively. No specific binding of [125I]oxyntomodulin or [125I]glucagon was detectable. GLP-1-(7-36) amide receptor mRNA was only detected in parietal cell-enriched fractions. GLP-1-(7-36) amide, oxyntomodulin and glucagon stimulated parietal cell cAMP production to similar maximal levels with median values close to 0.28 nM, 10.5 nM and 331.7 nM, whereas oxyntomodulin[19-37] had no effect. The maximal cAMP production induced by GLP-1-(7-36) amide, oxyntomodulin or glucagon was additive to that induced by histamine.(ABSTRACT TRUNCATED AT 250 WORDS)
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BACKGROUND: Gastroesophageal reflux and progressive esophageal dilatation can develop after gastric banding (GB). HYPOTHESIS: Gastric banding may interfere with esophageal motility, enhance reflux, or promote esophageal dilatation. DESIGN: Before-after trial in patients undergoing GB. SETTING: University teaching hospital. PATIENTS AND METHODS: Between January 1999 and August 2002, 43 patients undergoing laparoscopic GB for morbid obesity underwent upper gastrointestinal endoscopy, 24-hour pH monitoring, and stationary esophageal manometry before GB and between 6 and 18 months postoperatively. MAIN OUTCOME MEASURES: Reflux symptoms, endoscopic esophagitis, pressures measured at manometry, esophageal acid exposure. RESULTS: There was no difference in the prevalence of reflux symptoms or esophagitis before and after GB. The lower esophageal sphincter was unaffected by surgery, but contractions in the lower esophagus weakened after GB, in correlation with preoperative values. There was a trend toward more postoperative nonspecific motility disorders. Esophageal acid exposure tended to decrease after GB, with fewer reflux episodes. A few patients developed massive postoperative reflux. There was no clear correlation between preoperative testing and postoperative esophageal acid exposure, although patients with abnormal preoperative acid exposure tended to maintain high values after GB. CONCLUSIONS: Postoperative esophageal dysmotility and gastroesophageal reflux are not uncommon after GB. Preoperative testing should be done routinely. Low amplitude of contraction in the lower esophagus and increased esophageal acid exposure should be regarded as contraindications to GB. Patients with such findings should be offered an alternative procedure, such as Roux-en-Y gastric bypass.
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Many mucosal pathogens invade the host by initially infecting the organized mucosa-associated lymphoid tissue (o-MALT) such as Peyer's patches or nasal cavity-associated lymphoid tissue (NALT) before spreading systemically. There is no clear demonstration that serum antibodies can prevent infections in o-MALT. We have tested this possibility by using the mouse mammary tumor virus (MMTV) as a model system. In peripheral lymph nodes or in Peyer's patches or NALT, MMTV initially infects B lymphocytes, which as a consequence express a superantigen (SAg) activity. The SAg molecule induces the local activation of a subset of T cells within 6 days after MMTV infection. We report that similar levels of anti-SAg antibody (immunoglobulin G) in serum were potent inhibitors of the SAg-induced T-cell response both in peripheral lymph nodes and in Peyer's patches or NALT. This result clearly demonstrates that systemic antibodies can gain access to Peyer's patches or NALT.
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OBJECTIVE: To evaluate, during the first postoperative year in obese pre-menopausal women, the effects of laparoscopic gastric banding on calcium and vitamin D metabolism, the potential modifications of bone mineral content and bone mineral density, and the risk of development of secondary hyperparathyroidism. SUBJECTS: Thirty-one obese pre-menopausal women aged between 25 and 52 y with a mean body mass index (BMI) of 43.6 kg/m(2), scheduled for gastric banding were included. Patients with renal, hepatic, metabolic and bone disease were excluded. METHODS: Body composition and bone mineral density (BMD) were measured at baseline, 6 and 12 months after gastric banding using dual-energy X-ray absorptiometry. Serum calcium, phosphate, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, bilirubin, urea, creatinine, uric acid, proteins, parathormone, vitamin D(3), IGF-1, IGF-BP3 and telopeptide, as well as urinary telopeptide, were measured at baseline and 1, 3, 6, 9 and 12 months after surgery. RESULTS: After 1 y vitamin D3 remained stable and PTH decreased by 12%, but the difference was not significant. Serum telopeptide C increased significantly by 100% (P<0.001). There was an initial drop of the IGF-BP3 during the first 6 months (P<0.05), but the reduction was no longer significant after 1 y. The BMD of cortical bone (femoral neck) decreased significantly and showed a trend of a positive correlation with the increase of telopeptides (P<0.06). The BMD of trabecular bone, at the lumbar spine, increased proportionally to the reduction of hip circumference and of body fat. CONCLUSION: There is no evidence of secondary hyperparathyroidism 1 y after gastric banding. Nevertheless biochemical bone markers show a negative remodelling balance, characterized by an increase of bone resorption. The serum telopeptide seems to be a reliable parameter, not affected by weight loss, to follow up bone turnover after gastroplasty.
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Crohn's disease (CD), a major form of human inflammatory bowel disease, is characterized by primary immunodeficiencies. The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma) is essential for intestinal homeostasis in response to both dietary- and microbiota-derived signals. Its role in host defense remains unknown, however. We show that PPARgamma functions as an antimicrobial factor by maintaining constitutive epithelial expression of a subset of beta-defensin in the colon, which includes mDefB10 in mice and DEFB1 in humans. Colonic mucosa of Ppargamma mutant animals shows defective killing of several major components of the intestinal microbiota, including Candida albicans, Bacteroides fragilis, Enterococcus faecalis, and Escherichia coli. Neutralization of the colicidal activity using an anti-mDefB10 blocking antibody was effective in a PPARgamma-dependent manner. A functional promoter variant that is required for DEFB1 expression confers strong protection against Crohn's colitis and ileocolitis (odds ratio, 0.559; P = 0.018). Consistently, colonic involvement in CD is specifically linked to reduced expression of DEFB1 independent of inflammation. These findings support the development of PPARgamma-targeting therapeutic and/or nutritional approaches to prevent colonic inflammation by restoring antimicrobial immunity in CD.
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Gastric cancer incidence and mortality decreased substantially over the last decades in most countries worldwide, with differences in the trends and distribution of the main topographies across regions. To monitor recent mortality trends (1980-2011) and to compute short-term predictions (2015) of gastric cancer mortality in selected countries worldwide, we analysed mortality data provided by the World Health Organization. We also analysed incidence of cardia and non-cardia cancers using data from Cancer Incidence in Five Continents (2003-2007). The joinpoint regression over the most recent calendar periods gave estimated annual percent changes (EAPC) around -3% for the European Union (EU) and major European countries, as well as in Japan and Korea, and around -2% in North America and major Latin American countries. In the United States of America (USA), EU and other major countries worldwide, the EAPC, however, were lower than in previous years. The predictions for 2015 show that a levelling off of rates is expected in the USA and a few other countries. The relative contribution of cardia and non-cardia gastric cancers to the overall number of cases varies widely, with a generally higher proportion of cardia cancers in countries with lower gastric cancer incidence and mortality rates (e.g. the USA, Canada and Denmark). Despite the favourable mortality trends worldwide, in some countries the declines are becoming less marked. There still is the need to control Helicobacter pylori infection and other risk factors, as well as to improve diagnosis and management, to further reduce the burden of gastric cancer.
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Objective: Impaired blood flow of the gastric tube represents a major cause of anastomotic leakage after esophageal resection. In order to improve local vascularisation, preoperative embolization (PE) of the left gastric artery has recently been proposed. The aimof this study was to assess our initial experience of this novel approach with a particular focus on anastomotic leakage.Methods: A consecutive series of 102 patients (81 male, 21 female, median age 64 years) underwent resection (82 Ivor-Lewis procedures, 9 transhiatal resections, 11 triple incisions) for esophageal malignancies at our institution from 2000 to 2009. Since 2004, PE was used selectively in 19 patients 21 days prior to elective esophagectomy. Selection criteria were normal gastric vascular anatomy, no pre-existing vascular disease, i.e. atheromatosis of the celiac trunk or superior mesenteric artery, and resectability of the tumor. PE was performed under local anesthesia on a dedicated system in a standard fashion. Following percutaneous transfemoral visceral angiography to identify gastric vascular anatomy, embolization was performed either with 5-F or with coaxial 3-F catheters and fibered metal coils. We analyzed retrospectively patient's data, operative data, and outcome from a prospective database.Results: The overall anastomotic leakage rate was 18・6% (19/102 patients); cervical anastomosis had a leak rate of 25% compared to intrathoracic anastomosis leak rate of 18・2%. While 17 of 83 patients without PE developed anastomotic leakage (20・5%), there were only 2 of 19 patients after PE revealing an anastomotic leakage (10・5%). Otherwise, patients with PE had no more other complications. There was only one PE-related complication (i.e. partial splenic necrosis).Mean hospital stay was 25 days versus 27 days for patients with PE and without PE, respectively. The mortality rate was 7・8% (8/102 patients), whereby four deaths were related to anastomotic leakage (1 and 3 patients with PE and without PE, respectively).Conclusion: PE is an interesting novel approach to improve gastric blood flow in order to minimize anastomotic leakage. Its application is safe and technically easy. Our preliminary experience revealed a decrease of the anastomotic leakage rate of almost 50%.