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101.
Falk GW 《Seminars in gastrointestinal disease》2001,12(3):186-195
A variety of abnormalities contribute to the development of gastroesophageal reflux disease (GERD) including transient lower esophageal sphincter relaxation, low esophageal sphincter pressure, presence of a hiatal hernia, diminished esophageal clearance of refluxed gastric contents, and alterations in esophageal mucosal resistance. Helicobacter pylori infection clearly plays a role in the pathogenesis of peptic ulcer disease and mucosa associated lymphoma of the stomach and is a definite risk factor for distal gastric cancer. The role of H. pylori infection in GERD remains controversial and incompletely understood. Although H. pylori infection does not cause reflux disease, circumstantial evidence suggests that it may protect against the development of GERD and its complications in some patients. The most likely mechanism whereby H. pylori infection protects against GERD is by decreasing the potency of the gastric refluxate in patients with corpus predominant gastritis. A variety of implications of H. pylori infection on GERD treatment have also arisen in recent years. These focus on the risk of gastric atrophy while on proton pump inhibitor therapy and the efficacy of proton pump inhibitors before and after eradication of H. pylori. This article puts into perspective our current understanding of the complex, incompletely understood relationship between H. pylori infection and GERD. 相似文献
102.
Increased interleukin 8 expression in the colon mucosa of patients with inflammatory bowel disease. 总被引:32,自引:3,他引:32 下载免费PDF全文
To test whether there is a difference in the expression of interleukin 8 (IL8) between Crohn's disease and ulcerative colitis and to determine the main site of its synthesis this study analysed IL8 in mucosal biopsy specimens of patients with Crohn's disease and ulcerative colitis by enzyme linked immunosorbent assay (ELISA) and by in situ hybridisation. IL8 was measured by ELISA in 38 normal control patients, eight inflammatory control patients, 55 Crohn's disease biopsy specimens (26 patients), and 67 ulcerative colitis biopsy specimens (35 patients). IL8 mRNA was determined in samples by in situ hybridisation using a specific IL8 RNA probe. IL8 protein was significantly increased in macroscopically inflamed specimens of Crohn's disease (median 118 pg/specimen, p < 0.0001), ulcerative colitis (median 140 pg/specimen, p < 0.001), and inflammatory controls (median 30 pg/specimen, p = 0.010) compared with normal controls (median 4 pg/specimen). IL8 was also increased in uninflamed specimens of Crohn's disease (median 46 pg/specimen, p < 0.001) but not of ulcerative colitis patients (median 9 pg/specimen, p = 0.3). IL8 protein in the mucosa correlated significantly with macroscopic inflammation in Crohn's disease (r = 0.47, p < 0.001) and in ulcerative colitis (r = 0.60, p < 0.001). IL8 mRNA was detected by in situ hybridisation in 31 of 55 biopsy specimens (56%) of Crohn's disease patients, in 38 of 67 specimens of ulcerative colitis patients (57%), in five of eight inflammatory controls (63%) and in five of 38 normal controls (13%). Mucosal IL8 mRNA expression correlated with mucosal IL8 protein (r = 0.46, p < 0.001). IL8 mRNA was only detected in inflammatory cells of the interstitium but not in mucosal epithelial cells. IL8 is produced mainly in the lamina propria of the colon in inflammatory bowel disease and correlates with mucosal inflammation. 相似文献
103.
Rivoirard Romain Moncharmont Coralie Assouline Avi Auberdiac Pierre Mery Benoite Falk Alexander Tuan Annède Pierre Trone Jane-Chloé Guy Jean-Baptiste Vial Nicolas Fournel Pierre Merrouche Yacine Chargari Cyrus Magné Nicolas 《European archives of oto-rhino-laryngology》2015,272(3):719-725
European Archives of Oto-Rhino-Laryngology - In the field of radiotherapy, there is very little scientific data on the management of nonagenarians, especially in patients aged 90 years or... 相似文献
104.
105.
A critical review of the diagnosis and management of Barrett's esophagus: the AGA Chicago Workshop 总被引:35,自引:0,他引:35
Sharma P McQuaid K Dent J Fennerty MB Sampliner R Spechler S Cameron A Corley D Falk G Goldblum J Hunter J Jankowski J Lundell L Reid B Shaheen NJ Sonnenberg A Wang K Weinstein W;AGA Chicago Workshop 《Gastroenterology》2004,127(1):310-330
BACKGROUND & AIMS: The diagnosis and management of Barrett's esophagus (BE) are controversial. We conducted a critical review of the literature in BE to provide guidance on clinically relevant issues. METHODS: A multidisciplinary group of 18 participants evaluated the strength and the grade of evidence for 42 statements pertaining to the diagnosis, screening, surveillance, and treatment of BE. Each member anonymously voted to accept or reject statements based on the strength of evidence and his own expert opinion. RESULTS: There was strong consensus on most statements for acceptance or rejection. Members rejected statements that screening for BE has been shown to improve mortality from adenocarcinoma or to be cost-effective. Contrary to published clinical guidelines, they did not feel that screening should be recommended for adults over age 50, regardless of age or duration of heartburn. Members were divided on whether surveillance prolongs survival, although the majority agreed that it detects curable neoplasia and can be cost-effective in selected patients. The majority did not feel that acid-reduction therapy reduces the risk of esophageal adenocarcinoma but did agree that nonsteroidal antiinflammatory drugs are associated with a cancer risk reduction and are of promising (but unproven) value. Participants rejected the notion that mucosal ablation with acid suppression prevents adenocarcinoma in BE but agreed that this may be an appropriate strategy in a subgroup of patients with high-grade dysplasia. CONCLUSIONS: Based on this review of BE, the opinions of workshop members on issues pertaining to screening and surveillance are at variance with published clinical guidelines. 相似文献
106.
Brunilda Alushi Frederik Beckhoff David Leistner Marcus Franz Markus Reinthaler Barbara E. Stähli Andreas Morguet Hans R. Figulla Torsten Doenst Francesco Maisano Volkmar Falk Ulf Landmesser Alexander Lauten 《JACC: Cardiovascular Imaging》2019,12(4):591-601
Objectives
The authors investigated the development of pulmonary hypertension (PH), predictors of PH regression, and its prognostic impact on short, mid-, and long-term outcomes in patients undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS).Background
PH represents a common finding in patients with AS. Although TAVR is frequently associated with regression of PH, the predictors of reversible PH and its prognostic significance remain uncertain.Methods
In this study, 617 consecutive patients undergoing TAVR between 2009 and 2015 were stratified per baseline tertiles of pulmonary artery systolic pressure (PASP) as follows: normal (PASP <34 mm Hg), mild-to-moderate (PASP ≥34 mm Hg and <46 mm Hg), and severe PASP elevation (PASP ≥46 mm Hg). After TAVR, 520 patients with PH at discharge were stratified according to the presence or absence of PASP reduction. Primary outcome was all-cause mortality at 30 days, 1 year, and long-term follow-up at a maximum of 5.9 years.Results
In patients with both mild-to-moderate and severe PH at baseline, PASP decreased significantly at discharge (ΔPASP 3.0 ± 9.3 mm Hg and 12.0 ± 10.0 mm Hg, respectively) and 1 year (ΔPASP 5.0 ± 9.7 mm Hg and 18.0 ± 14.0 mm Hg, respectively). At a median follow-up of 370 days (interquartile range [IQR]: 84 to 500 days), the risk of all-cause mortality was similar among baseline PASP groups at all time intervals evaluated. After TAVR, a significant regression of PH was observed in 46% of patients. Contrarily, patients with residual PH had a higher risk of all-cause mortality at 30 days (hazard ratio [HR]: 3.49, 95% confidence interval [CI]: 1.74 to 6.99; p < 0.001), 1 year (HR: 3.12, 95% CI: 2.06 to 4.72; p < 0.001), and long-term (HR: 2.47, 95% CI: 1.74 to 3.49; p < 0.001). Left ventricular ejection fraction (LVEF) >40% (odds ratio [OR]: 3.56, 95% CI: 2.24 to 5.65; p < 0.001), baseline PASP ≥46 mm Hg (OR: 3.26, 95% CI: 2.07 to 5.12; p < 0.001), absence of concomitant tricuspid regurgitation (TR) ≥ moderate (OR: 0.53, 95% CI: 0.34 to 0.84; p < 0.001), and logistic EuroSCORE <25% (OR: 1.59, 95% CI: 1.04 to 2.45; p = 0.03) were independent predictors of PASP reduction.Conclusions
In most patients with PH and AS, TAVR is associated with a significant early and late reduction of PASP. Patients with reversible PH after TAVR are at lower risk of all-cause mortality at early, mid-, and long-term follow-up. Therefore, the presence of PH should not preclude treatment with TAVR. 相似文献107.
Different response to balloon angioplasty of carotid and coronary arteries: effects on acute platelet deposition and intimal thickening 总被引:4,自引:0,他引:4
Juan Jose Badimon Antonio Fernandez Ortiz Beat Meyer Alessandra Mailhac John T Fallon Erling Falk Lina Badimon James H Chesebro Valentin Fuster 《Atherosclerosis》1998,140(2):307-314
PTCA is a well-established intervention to reduce the severity of atherosclerotic coronary stenosis. Its primary success rate is seriously handicapped by the high incidence of late restenosis. Given the clinical and social importance of this proliferative process, new strategies are needed to prevent or reduce restenosis. Several animal models as well as different arteries have been used to study neointimal proliferation after arterial injury. A number of agents have shown to reduce neointimal proliferation after arterial injury in the carotids and iliac arteries of rodent models. Unfortunately, these results have not been replicated in humans. We have compared the acute and late response to vascular injury of the carotid and coronary arteries in the pig. Arterial injury was induced by performing balloon angioplasty of the carotid (elastic) and coronary (muscular) arteries in swine. Acute platelet-thrombus formation was evaluated by quantitation of Indium-labeled platelets deposited on the injured segments 1 h after procedure. Measurement of intimal area was performed by morphometry of the most stenotic cross-section at 28 days after balloon angioplasty. Platelet deposition after mild and severe injury in carotids (4±1 and 56±13×106 platelets/cm2, respectively) and coronaries (15±5 and 141±20×106 platelets/cm2, respectively) are significantly greater in deep, than in mild injury (P<0.005), and significantly greater in coronary than in carotid arteries after deep injury (P<0.05). Likewise, late neointima formation was significantly greater (P<0.05) after mild and severe injury in coronary (17±0.5 and 56 ±2%, respectively) than in carotid arteries (5±0.5 and 12±1%, respectively). Acute platelet-thrombus formation and late neointimal thickening are modulated by the degree of injury induced during the interventions; and after disruption of the internal elastic lamina, coronary arteries always had significantly more acute thrombus and neointimal thickening. This study emphasizes the importance of the animal species, the type of injury and the artery chosen for studies on restenosis post interventions. 相似文献
108.
Dr. Doris H. B. Palvio M.D. Erik Steen Kristensen M.D. Erling Falk M.D. 《Diseases of the colon and rectum》1985,28(10):746-748
A case of a carcinoid tumor arising in a Meckel's diverticulum is reported. By the time of detection, the tumor had spread
to the mesentery causing ischemia of the small intestine due to the associated vascular elastosis. 相似文献
109.
Ming Jiang Wei-Yao Ku Zhongren Zhou Evan S. Dellon Gary W. Falk Hiroshi Nakagawa Mei-Lun Wang Kuancan Liu Jun Wang David A. Katzka Jeffrey H. Peters Xiaopeng Lan Jianwen Que 《The Journal of clinical investigation》2015,125(4):1557-1568
Tissue homeostasis requires balanced self-renewal and differentiation of stem/progenitor cells, especially in tissues that are constantly replenished like the esophagus. Disruption of this balance is associated with pathological conditions, including eosinophilic esophagitis (EoE), in which basal progenitor cells become hyperplastic upon proinflammatory stimulation. However, how basal cells respond to the inflammatory environment at the molecular level remains undetermined. We previously reported that the bone morphogenetic protein (BMP) signaling pathway is critical for epithelial morphogenesis in the embryonic esophagus. Here, we address how this pathway regulates tissue homeostasis and EoE development in the adult esophagus. BMP signaling was specifically activated in differentiated squamous epithelium, but not in basal progenitor cells, which express the BMP antagonist follistatin. Previous reports indicate that increased BMP activity promotes Barrett’s intestinal differentiation; however, in mice, basal progenitor cell–specific expression of constitutively active BMP promoted squamous differentiation. Moreover, BMP activation increased intracellular ROS levels, initiating an NRF2-mediated oxidative response during basal progenitor cell differentiation. In both a mouse EoE model and human biopsies, reduced squamous differentiation was associated with high levels of follistatin and disrupted BMP/NRF2 pathways. We therefore propose a model in which normal squamous differentiation of basal progenitor cells is mediated by BMP-driven NRF2 activation and basal cell hyperplasia is promoted by disruption of BMP signaling in EoE. 相似文献
110.
Raimund HM Preidl Tobias Ebker Martin Raithel Falk Wehrhan Friedrich W Neukam Philipp Stockmann 《BMC gastroenterology》2014,14(1):1-6