33 results on '"Stack WA"'
Search Results
2. Chimeric Monoclonal Antibody cA2 to Tumor Necrosis Factor α for Crohn's Disease
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Stack Wa and Hawkey Cj
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Crohn's disease ,Tumor Necrosis Factor-alpha ,business.industry ,Recombinant Fusion Proteins ,Antibodies, Monoclonal ,Monoclonal antibody ca2 ,General Medicine ,medicine.disease ,Crohn Disease ,medicine ,Cancer research ,Humans ,Tumor necrosis factor alpha ,business - Published
- 1998
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3. Novel approaches to inflammatory bowel disease
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McKaig, BC, primary and Stack, WA, additional
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- 1998
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4. Adult human colonic subepithelial myofibroblasts (HCSM) regulate epithelial secretory response and barrier function via distinct pathways
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Beltinger, J, primary, Makh, S, additional, Stack, WA, additional, Hawkey, CJ, additional, and Mahida, YR, additional
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- 1998
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5. Nitric oxide donating flurbiprofen (HCT 1026) causes less endoscopic damage in healthy volunteers than flurbiprofen
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Donnelly, MT, primary, Stack, WA, additional, Courtauld, EM, additional, Garlick, N, additional, Del Soldato, P, additional, and Hawkey, CJ, additional
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- 1998
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6. NSAIDs and CagA positive H. pylori but not CagA negative H. pylori as independent risk factors for bleeding peptic ulcers
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Stack, WA, primary, Hawkey, GM, additional, Atherton, JC, additional, Pearson, G, additional, Everitt, S, additional, Fielding, K, additional, Logan, RFA, additional, and Hawkey, CJ, additional
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- 1998
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7. Dose response study comparing endoscopic damage of three different doses of ketoprofen with one dose of ibuprofen
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Donnelly, MT, primary, Stack, WA, additional, Richardson, P, additional, Courtauld, EM, additional, Lange, R, additional, and Hawkey, CJ, additional
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- 1998
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8. Blood in the stomach as a surrogate for clinical end points in GI bleeding trials
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Hawkey, GM, primary, Stack, WA, additional, Cole, AT, additional, Long, RG, additional, Logan, RFA, additional, and Hawkey, CJ, additional
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- 1998
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9. Nicroencapsulated aspirin, asacard, reduces endoscopic damage in healthy volunteers compared to conventional encapsulated aspirin
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Donnelly, MT, primary, Stack, WA, additional, Richardson, P, additional, Courtauld, EM, additional, Allan, LM, additional, Kiff, PS, additional, and Hawkey, CJ, additional
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- 1998
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10. Randomised controlled trial of CDP571 antibody to tumour necrosis factor-α in Crohn's disease
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Stack, WA, primary, Mann, SD, additional, Roy, AJ, additional, Heath, P, additional, Sopwith, M, additional, Freeman, J, additional, Holmes, G, additional, Long, R, additional, Forbes, A, additional, Kamm, MA, additional, and Hawkey, CJ, additional
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- 1997
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11. Activation of Phagocytes Stimulates Human Colonic Ion Transport in Vitro
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Stack, WA, primary, Keely, SJ, primary, O'Donoghue, DP, primary, Baird, AW, primary, and Hawkey, CJ, primary
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- 1994
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12. A randomised controlled trial of ursodeoxycholic acid vs placebo in addition to an endoprosthetic stent for defiant common bile duct stones
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Stack, Wa, Craig, J., Vautier, G., Muller, F., Ryder, Sd, and robin spiller
13. NSAIDs and CagA positive H. pyloribut not CagA negative H. pylorias independent risk factors for bleeding peptic ulcers
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Stack, WA, Hawkey, GM, Atherton, JC, Pearson, G, Everitt, S, Fielding, K, Logan, RFA, and Hawkey, CJ
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- 1998
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14. Disseminated cryptococcal infection initially presenting as cryptococcal cellulitis in an HIV-negative patient on long-term steroids.
- Author
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Kerr C, Stack WA, Sadlier C, and Jackson A
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- Administration, Intravenous, Aged, Animals, Anti-Bacterial Agents therapeutic use, Antifungal Agents therapeutic use, Cellulitis diagnostic imaging, Cellulitis pathology, Columbidae, Cryptococcosis pathology, Cryptococcus neoformans isolation & purification, Humans, Male, Mycoses pathology, Rare Diseases, Skin pathology, Treatment Outcome, Upper Extremity pathology, Cellulitis etiology, Cryptococcosis etiology, Cryptococcus isolation & purification, Mycoses etiology
- Abstract
Cryptococcosis is an invasive fungal infection caused by encapsulated yeasts of the Cryptococcus species. Inoculation usually occurs by inhalation through the respiratory tract, where it can then spread haematogenously to various sites, such as the central nervous system or the skin, in susceptible patients. We present the case of a 68-year-old male patient on long-term steroids who presented with a right upper limb cellulitis not responding to antibiotics. This was subsequently diagnosed as cryptococcal cellulitis on an urgent skin biopsy. Wound swabs and blood cultures, which were initially negative, were repeated and confirmed the presence of disseminated cryptococcal disease. The patient's neighbours kept racing pigeons and this was hypothesised as a potential source of infection., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2018. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2018
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15. Disruption of colonic barrier function and induction of mediator release by strains of Campylobacter jejuni that invade epithelial cells.
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Beltinger J, del Buono J, Skelly MM, Thornley J, Spiller RC, Stack WA, and Hawkey CJ
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- Cell Line, Tumor, Dinoprostone metabolism, Humans, Interleukin-8 metabolism, L-Lactate Dehydrogenase metabolism, Mannitol metabolism, Models, Biological, Adenocarcinoma pathology, Bacterial Translocation physiology, Campylobacter jejuni pathogenicity, Cell Membrane Permeability physiology, Colonic Neoplasms pathology, Epithelial Cells microbiology, Epithelial Cells pathology
- Abstract
Aim: To study the mechanisms by which Campylobacter jejuni (C. jejuni) causes inflammation and diarrhea. In particular, direct interactions with intestinal epithelial cells and effects on barrier function are poorly under-stood., Methods: To model the initial pathogenic effects of C. jejuni on intestinal epithelium, polarized human colonic HCA-7 monolayers were grown on permeabilized filters and infected apically with clinical isolates of C. jejuni. Integrity of the monolayer was monitored by changes in monolayer resistance, release of lactate dehydrogenase, mannitol fluxes and electron microscopy. Invasion of HCA-7 cells was assessed by a modified gentamicin protection assay, translocation by counting colony forming units in the basal chamber, stimulation of mediator release by immunoassays and secretory responses in monolayers stimulated by bradykinin in an Ussing chamber., Results: All strains translocated across monolayers but only a minority invaded HCA-7 cells. Strains that invaded HCA-7 cells destroyed monolayer resistance over 6 h, accompanied by increased release of lactate dehydrogenase, a four-fold increase in permeability to [(3)H] mannitol, and ultrastructural disruption of tight junctions, with rounding and lifting of cells off the filter membrane. Synthesis of interleukin (IL)-8 and prostaglandin E(2) was increased with strains that invaded the monolayer but not with those that did not., Conclusion: These data demonstrate two distinct effects of C. jejuni on colonic epithelial cells and provide an informative model for further investigation of initial host cell responses to C. jejuni.
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- 2008
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16. Increased risk of myocardial infarction as first manifestation of ischaemic heart disease and nonselective nonsteroidal anti-inflammatory drugs.
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Hawkey CJ, Hawkey GM, Everitt S, Skelly MM, Stack WA, and Gray D
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- Adult, Aged, Aged, 80 and over, Case-Control Studies, Female, Humans, Male, Middle Aged, Myocardial Infarction chemically induced, Prospective Studies, Risk Factors, Anti-Inflammatory Agents, Non-Steroidal adverse effects, Aspirin adverse effects, Cyclooxygenase 2 Inhibitors adverse effects, Myocardial Ischemia chemically induced, Naproxen adverse effects
- Abstract
Aims: Selective cyclooxygenase (COX)-2 inhibitors have recently been implicated as enhancing risk of myocardial infarction (MI). Nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) are also effective COX-2 inhibitors, so we investigated the hypothesis that they too increase risk of MI., Methods: We conducted a case-control study with direct structured interview of cases and controls. Cases were all subjects (N = 205) with a first nonfatal MI who had no previously recognized cardiovascular disease. Community controls (N = 258) were randomly selected from the same practice as the index case. Hospital controls (N = 205) were those admitted at the same time as index cases for nonmyocardial conditions not influenced by NSAID use. The effects of aspirin, NSAIDs and previously recognized influences on MI were investigated by unconditional logistic regression analysis., Results: NSAID use was associated with an increase risk of MI with an odds ratio of 1.77 (1.03, 3.03) vs. community controls and 2.61 (1.38, 4.95) vs. hospital controls. These values were 5.00 (1.18, 21.28) and 7.66 (0.87, 67.48), respectively, in aspirin users. Results were similar when naproxen was grouped with aspirin. Odds ratios for smoking and for use of antidiabetic medication were 3.91 (2.52, 6.04) and 3.92 (1.25, 12,33), respectively, vs. community controls., Conclusions: Like selective COX-2 inhibitors, non-selective NSAIDs [corrected] are associated with an increased risk of MI. The extent to which this reflects interference with aspirin warrants further investigation.
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- 2006
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17. Interactions between Helicobacter pylori and other risk factors for peptic ulcer bleeding.
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Stack WA, Atherton JC, Hawkey GM, Logan RF, and Hawkey CJ
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- Adult, Aged, Anti-Inflammatory Agents, Non-Steroidal adverse effects, Aspirin adverse effects, Bacterial Proteins genetics, Case-Control Studies, Duodenal Ulcer chemically induced, Duodenal Ulcer complications, Duodenal Ulcer etiology, Duodenal Ulcer microbiology, Female, Helicobacter Infections drug therapy, Helicobacter Infections microbiology, Helicobacter pylori genetics, Humans, Male, Middle Aged, Odds Ratio, Peptic Ulcer Hemorrhage chemically induced, Peptic Ulcer Hemorrhage complications, Risk Factors, Smoking adverse effects, Antigens, Bacterial, Helicobacter Infections complications, Helicobacter pylori pathogenicity, Peptic Ulcer Hemorrhage etiology, Peptic Ulcer Hemorrhage microbiology
- Abstract
Aim: To investigate the role of Helicobacter pylori, expressing the virulence marker CAGA (cytotoxin associated gene product A) in ulcer complications and its interaction with nonsteroidal anti-inflammatory drugs (NSAIDs) and other risk factors., Design: Case control study using conditional logistic regression analysis., Setting: University and City Hospitals, Nottingham., Subjects: 203 consecutive patients with ulcer bleeding and 203 age- and sex-matched controls., Results: Ulcer bleeding was more likely with positive H. pylori serology (odds ratio = 3.3, 95% CI: 1.7--6.6 for CagA positive, but only OR = 1.6, 95% CI: 0.7-3.7 for CagA negative serology), current smoking (OR 2.2, 95% CI: 1.04-4.7), aspirin < or = 300 mg daily (OR 7.7, 95% CI: 2.8-20.6), all other nonsteroidal anti-inflammatory drugs (NSAIDs: OR 10.6, 95% CI: 3.1-35.7 for < or = 1 defined daily dose lower and OR 22.6, 95% CI: 6.2-82.0 for higher doses) and past ulcer history (OR 5.6, 95% CI: 2.3-14.1). Aspirin < or = 300 mg daily was used by 25.1% of patients vs. 7.4% of controls. Smoking only enhanced risk in the presence of H. pylori, with a synergistic interaction (interaction odds ratio = 4.9, 2.4-9.9, P=0.002). Conversely, risks with non-aspirin NSAIDs were reduced in the presence of H. pylori, particularly if CagA-positive (interaction odds ratio=0.21, 0.05-0.9, P=0.03)., Conclusions: CagA positive H. pylori infection is associated with an increased risk of ulcer bleeding. The risk from non-aspirin NSAIDs is even higher, but is less in H. pylori infected people. Low-dose aspirin is now commonly associated with ulcer bleeding.
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- 2002
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18. Nocardia asteroides lung abscess in acute ulcerative colitis treated with cyclosporine.
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Stack WA, Richardson PD, Logan RP, Mahida YR, and Hawkey CJ
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- Acute Disease, Aged, Colitis, Ulcerative drug therapy, Humans, Lung Abscess complications, Lung Abscess diagnostic imaging, Male, Nocardia Infections complications, Nocardia Infections diagnostic imaging, Opportunistic Infections complications, Opportunistic Infections diagnostic imaging, Radiography, Colitis, Ulcerative complications, Cyclosporine therapeutic use, Immunosuppressive Agents therapeutic use, Lung Abscess diagnosis, Nocardia Infections diagnosis, Nocardia asteroides, Opportunistic Infections diagnosis
- Abstract
Cyclosporine is a potent suppresser of cell-mediated immunity that is mainly used in organ transplantation to prevent rejection. It is also being used increasingly outside of transplantation and probably is the only new treatment to have made an impact in acute ulcerative colitis (UC) resistant to steroid therapy. We describe a case of Nocardia asteroides lung abscess in a patient treated with cyclosporine for acute steroid resistant UC that was successfully managed with antibiotics and by discontinuing cyclosporine. With increasing use of cyclosporine for acute UC it is to be anticipated that opportunistic infections such as Nocardia will be more frequently encountered in the future.
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- 2001
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19. Dose-dependent effects of ketoprofen on the human gastric mucosa in comparison with ibuprofen.
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Donnelly MT, Richardson P, Hawkey CJ, Courtauld E, and Stack WA
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- Administration, Oral, Adult, Anti-Inflammatory Agents, Non-Steroidal administration & dosage, Cross-Over Studies, Dose-Response Relationship, Drug, Double-Blind Method, Drug Administration Schedule, Female, Gastric Mucosa pathology, Humans, Ibuprofen administration & dosage, Ketoprofen administration & dosage, Male, Prostaglandins biosynthesis, Self Medication, Stomach Ulcer chemically induced, Stomach Ulcer pathology, Therapeutic Equivalency, Anti-Inflammatory Agents, Non-Steroidal adverse effects, Gastric Mucosa drug effects, Ibuprofen adverse effects, Ketoprofen adverse effects
- Abstract
Background: As non-steroidal anti-inflammatory drugs (NSAIDs) become available for over-the-counter use, it is important to define doses that would not cause undue gastroduodenal damage during the short periods for which self-medication with NSAIDs is licensed., Aim: To establish what dose of ketoprofen most closely resembles the maximum dose of ibuprofen (400 mg t.d.s.) licensed for self-medication., Methods: We studied healthy volunteers in a double-blind double-dummy randomized crossover study. Each subject took, over four separate 10-day dosing periods, ibuprofen 400 mg t.d.s., ketoprofen 12.5 mg t.d.s., ketoprofen 25 mg t.d.s. or ketoprofen 50 mg t.d.s. Mucosal injury was assessed by endoscopy at baseline and on the 3rd and 10th day of each dosing period. Ex vivo gastric mucosal prostaglandin (PG) E2 evoked by vortex mixing was measured by radioimmunoassay. Serum thromboxane was also measured by radioimmunoassay., Results: Ketoprofen 50 mg t.d.s. suppressed prostaglandin synthesis to a significantly greater extent than ibuprofen and caused significantly more gastroduodenal injury. The profile of prostaglandin synthesis and injury on ketoprofen 12.5 mg t.d.s. most closely resembled that of ibuprofen 400 mg t.d.s., Conclusions: Ketoprofen 12.5 mg t.d.s. is an appropriate dose for self-medication, which is likely to be similar to ibuprofen 400 mg t. d.s. in its effects on the stomach and duodenum.
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- 2000
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20. Current pharmacotherapy for inflammatory bowel disease.
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McKaig BC and Stack WA
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- Clinical Trials as Topic, Colitis, Ulcerative drug therapy, Crohn Disease drug therapy, Humans, Gastrointestinal Agents therapeutic use, Inflammatory Bowel Diseases drug therapy
- Abstract
Ulcerative colitis (UC) and Crohn's disease (CD), collectively termed inflammatory bowel disease (IBD), are chronic spontaneously relapsing enteropathies of unknown aetiology. Pharmacotherapy for IBD has essentially been unchanged for over twenty years, with therapy based around 5-aminosalicylic acid (5-ASA) preparations, corticosteroids, antibiotics and immunosuppression. Much of the controversy surrounding optimal use of these drugs in IBD arises as a consequence of methodological deficiencies in many of the early trials combined with the difficulty in consistent patient selection due to the heterogeneous nature of both UC and CD. More recently, well-designed clinical trials have attempted to provide an 'evidence based' approach to managing IBD which, in time, will allow optimisation of current therapies and accurate evaluation of novel agents. Over the past two decades, improved research methodology has considerably increased our molecular understanding of the aetiopathogenesis of IBD which has ultimately lead to the development of specific mediator directed or 'designer' drug therapy for IBD. This review evaluates the literature on current IBD therapy, summarises the important recent studies which have made an impact on clinical practice, and examines the risks and benefits of the novel agents which are currently under investigation in clinical trials of IBD therapy.
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- 1999
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21. Human colonic subepithelial myofibroblasts modulate transepithelial resistance and secretory response.
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Beltinger J, McKaig BC, Makh S, Stack WA, Hawkey CJ, and Mahida YR
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- Biological Transport drug effects, Bradykinin pharmacology, Carbachol pharmacology, Cell Line, Coculture Techniques, Colon cytology, Cyclooxygenase 1, Cyclooxygenase 2, Electric Impedance, Fibroblasts cytology, Fibroblasts drug effects, Fibroblasts metabolism, Humans, Intestinal Mucosa metabolism, Ions, Isoenzymes metabolism, Membrane Proteins, Muscle, Smooth cytology, Muscle, Smooth drug effects, Muscle, Smooth metabolism, Prostaglandin-Endoperoxide Synthases metabolism, Transforming Growth Factor beta metabolism, Transforming Growth Factor beta physiology, Colon physiology, Fibroblasts physiology, Intestinal Mucosa physiology, Muscle, Smooth physiology
- Abstract
The epithelium of the gastrointestinal tract transports ions and water but excludes luminal microorganisms and toxic molecules. The factors regulating these important functions are not fully understood. Intestinal myofibroblasts lie subjacent to the basement membrane, at the basal surface of epithelial cells. We recently showed that primary cultures of adult human colonic subepithelial myofibroblasts express cyclooxygenase (COX)-1 and COX-2 enzymes and release bioactive transforming growth factor-beta (TGF-beta). In this study we have investigated the role of normal human colonic subepithelial myofibroblasts in the regulation of transepithelial resistance and secretory response in HCA-7 and T84 colonic epithelial cell lines. Cocultures of epithelial cells-myofibroblasts and medium conditioned by myofibroblasts enhanced transepithelial resistance and delayed mannitol flux. A panspecific antibody to TGF-beta (but not piroxicam) antagonized this effect. In HCA-7 cells, myofibroblasts downregulated secretagogue-induced change in short-circuit current, and this effect was reversed by pretreatment of myofibroblasts with piroxicam. In contrast to HCA-7 cells, myofibroblasts upregulated the agonist-induced secretory response in T84 cells. This study shows that intestinal subepithelial myofibroblasts enhance barrier function and modulate electrogenic chloride secretion in epithelial cells. The enhancement of barrier function was mediated by TGF-beta. In contrast, the modulation of agonist-induced change in short-circuit current was mediated by cyclooxygenase products. These findings suggest that colonic myofibroblasts regulate important functions of epithelial cells via distinct secretory products.
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- 1999
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22. Immunosuppressive therapy for ulcerative colitis: results of a nation-wide survey among consultant physician members of the British Society of Gastroenterology.
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Stack WA, Williams D, Stevenson M, and Logan RF
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- Azathioprine adverse effects, Azathioprine therapeutic use, Cyclosporine adverse effects, Cyclosporine therapeutic use, Humans, Referral and Consultation, Colitis, Ulcerative drug therapy, Immunosuppressive Agents therapeutic use
- Abstract
Background: The role of immunosuppressive therapy in ulcerative colitis remains controversial. There is little information available on how frequently immunosuppressives are used, the circumstances, dose and duration of use and perceived benefit., Methods: A postal survey was sent to consultant gastroenterologist members of the British Society of Gastroenterology., Results: Questionnaires were returned by 81% of the 496 UK consultants approached. Azathioprine use was frequent, with 93% reporting previous use and 86% use within the past year. Although 95% usually prescribed a < or =2 mg/kg dose, only 39% were prepared to prescribe higher doses. There was marked variation in duration of use, with 46% using azathioprine for <2 years and 17% continuing it for 4 years or longer. Consultants with more experience of azathioprine in ulcerative colitis used it at higher maintenance doses for longer periods, and in patients with less extensive disease. Cyclosporin use was reported by 47% of those caring for ulcerative colitis patients, with 36% having used it at least once in the past year. However, 65% of users estimated that fewer than 50% of patients subsequently avoided colectomy. On stopping cyclosporin only 21% always introduced an alternative immunosuppressive, while 23% never did so. Potentially serious side-effects attributable to azathioprine and cyclosporin were reported by 36% and 45% of users of each drug, respectively., Conclusions: This survey reveals considerable variation in the amount and pattern of immunosuppressive use in ulcerative colitis, with serious side-effects commonly seen. There is a pressing need for further randomized controlled trials to provide reliable evidence as to how immunosuppressive therapy should be used in ulcerative colitis.
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- 1999
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23. TGF-alpha reduces bradykinin-stimulated ion transport and prostaglandin release in human colonic epithelial cells.
- Author
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Beltinger J, Hawkey CJ, and Stack WA
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- Arachidonic Acid pharmacology, Carbachol pharmacology, Cell Line, Colforsin pharmacology, Colon, Cyclic AMP metabolism, Cyclooxygenase 1, Cyclooxygenase 2, Dinoprostone pharmacology, Humans, Intestinal Mucosa drug effects, Kinetics, Membrane Potentials drug effects, Membrane Potentials physiology, Membrane Proteins, Time Factors, Transforming Growth Factor alpha physiology, Bradykinin pharmacology, Chlorides metabolism, Dinoprostone biosynthesis, Intestinal Mucosa physiology, Isoenzymes metabolism, Prostaglandin-Endoperoxide Synthases metabolism, Transforming Growth Factor alpha pharmacology
- Abstract
The effect of chronic exposure to transforming growth factor-alpha (TGF-alpha) on bradykinin-stimulated acute prostanoid production and ion secretion in monolayers of HCA-7 colony 29 colonic epithelial cells has been studied. Monolayers synthesized prostaglandin E2 (PGE2) at a basal rate of 2.10 +/- 0.31 pg. monolayer-1. min-1 over 24 h. Bradykinin (10(-8)-10(-5) M) dose dependently increased acute PGE2 release by three orders of magnitude. This was associated with a rise in cAMP from 1.60 +/- 0.14 to 2.90 +/- 0.1 pmol/monolayer (P < 0.02) and a dose-dependent increase in short-circuit current (SCC). When monolayers were primed by a 24-h exposure to TGF-alpha, basal PGE2 release rose to 6.31 +/- 0.38 pg. monolayer-1. min-1 (TGF-alpha concn 10 ng/ml; P = 0.001). However, the stimulation of acute prostaglandin release, intracellular cAMP, and increased SCC by bradykinin was significantly reduced by preincubation with TGF-alpha. Priming with PGE2 (10(-8)-10(-6) M) over 24 h mimicked the effect of TGF-alpha on bradykinin-induced changes in cAMP and SCC. These data suggest that enhanced chronic release of prostaglandins in response to stimulation with TGF-alpha may downregulate acute responses to bradykinin. In vivo, TGF-alpha could have an important modulatory function in regulating secretion under inflammatory conditions.
- Published
- 1999
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24. Novel treatments in inflammatory bowel disease.
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Pathmakanthan S and Stack WA
- Subjects
- Humans, Gastrointestinal Agents therapeutic use, Inflammatory Bowel Diseases drug therapy
- Abstract
Recent advances in inflammatory bowel disease therapeutics have led to improved formulations of existing treatments and new indications for established drugs. Truly novel therapies based on recent understanding of pathogenesis are also being developed. These new treatments and their likely impact on the management of inflammatory bowel disease in the future are discussed.
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- 1999
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25. Lack of effectiveness of the platelet-activating factor antagonist SR27417A in patients with active ulcerative colitis: a randomized controlled trial. The Platelet Activating Factor Antagonist Study Group in Ulcerative Colitis.
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Stack WA, Jenkins D, Vivet P, and Hawkey CJ
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- Adult, Double-Blind Method, Female, Humans, Male, Middle Aged, Colitis, Ulcerative drug therapy, Platelet Activating Factor antagonists & inhibitors, Thiazoles therapeutic use
- Abstract
Background & Aims: Platelet-activating factor (PAF) is increased during relapse of ulcerative colitis. In animal models of experimental colitis, specific inhibition of PAF has reduced inflammation. The aim of this study was to evaluate the efficacy and safety of the PAF antagonist SR27417A in moderately active UC., Methods: A double-blind multicenter trial was conducted during a 28-day period in hospital outpatients with an exacerbation of ulcerative colitis. Patients were randomized to receive 10 mg/day SR27417A or placebo, and both groups were also given 2.4 g mesalazine. Patient classification at the end of the treatment period was based on sigmoidoscopy and clinical scores., Results: One hundred fifty-one subjects entered the study (75 placebo and 76 SR27417A). The remission rate between placebo- and SR27417A-treated patients at 28 days was not significantly different (29.0% and 35.6% respectively; P = 0.44). Similarly, 49.2% treated with SR27417A had a definite or possible improvement of their symptom score compared with 48.3% of those treated with placebo (P = 0.43). Four subjects in the placebo group and 5 subjects in the SR27417A group discontinued the drug treatment because of adverse events. No significant adverse events were thought to be caused by SR27417A., Conclusions: Although the specific PAF antagonist SR27417A is safe in humans, there is no evidence of efficacy in the treatment of acute ulcerative colitis.
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- 1998
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26. Short- and long-term outcome of patients treated with cyclosporin for severe acute ulcerative colitis.
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Stack WA, Long RG, and Hawkey CJ
- Subjects
- Cyclosporine adverse effects, Female, Follow-Up Studies, Humans, Male, Time Factors, Treatment Outcome, Colitis, Ulcerative drug therapy, Cyclosporine therapeutic use, Immunosuppressive Agents therapeutic use
- Abstract
Background: Recent evidence suggests that the immunosuppressive drug cyclosporin may be of benefit in treating patients with severe colitis who are steroid resistant. Although cyclosporin appears to be effective in reducing colectomy rates in the short term, few data are available on the long-term follow-up of such patients., Aim: To investigate the short- and long-term outcome of patients with severe steroid-resistant ulcerative colitis treated with cyclosporin who were otherwise being considered for colectomy., Methods: Twenty-two patients with severe steroid-resistant exacerbations of ulcerative colitis who were being considered for colectomy were treated with cyclosporin (4 mg/kg i.v.) daily for 7 days followed by oral treatment (6 mg/kg/day) if colectomy was avoided., Results: Twenty of 22 patients (91%) avoided colectomy during their initial hospital admission. With a mean follow-up period of 39 months (range 31-59), eight of these patients have subsequently relapsed and required colectomy and 12 patients have avoided colectomy (53%). Of the 12 patients avoiding colectomy, seven have successfully been weaned on to azathioprine while five are maintained on an aminosalicylate alone. None of these long-term responders require maintenance corticosteroids. The main side-effects during treatment with cyclosporin were headaches (six patients, 27%), paraesthesia and tremors (four patients, 18%) and hypertension (four patients, 18%). Two patients developed renal impairment on cyclosporin which resolved on lowering the dose. In no case was cyclosporin discontinued because of an adverse reaction. No clinical or laboratory features could be identified that predicted which patients treated with cyclosporin would later require colectomy., Conclusion: This study shows that cyclosporin is a viable alternative to emergency colectomy in severe ulcerative colitis in the short term. Although these benefits are not maintained in all patients, more than half were found to avoid colectomy in the longer term.
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- 1998
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27. Safety and efficacy of rabeprazole in combination with four antibiotic regimens for the eradication of Helicobacter pylori in patients with chronic gastritis with or without peptic ulceration.
- Author
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Stack WA, Knifton A, Thirlwell D, Cockayne A, Jenkins D, Hawkey CJ, and Atherton JC
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- 2-Pyridinylmethylsulfinylbenzimidazoles, Amoxicillin therapeutic use, Anti-Ulcer Agents adverse effects, Benzimidazoles adverse effects, Clarithromycin therapeutic use, Double-Blind Method, Drug Therapy, Combination adverse effects, Female, Gastritis drug therapy, Helicobacter Infections complications, Humans, Male, Metronidazole therapeutic use, Middle Aged, Omeprazole analogs & derivatives, Peptic Ulcer drug therapy, Rabeprazole, Time Factors, Treatment Outcome, Anti-Ulcer Agents therapeutic use, Benzimidazoles therapeutic use, Drug Therapy, Combination therapeutic use, Gastritis microbiology, Helicobacter Infections drug therapy, Helicobacter pylori, Peptic Ulcer microbiology, Proton-Translocating ATPases antagonists & inhibitors
- Abstract
Objectives: Rabeprazole is a new fast acting proton pump inhibitor that has recently been proven to be effective in the treatment of peptic ulceration and reflux esophagitis. The aim of this study was to evaluate rabeprazole in combination with antibiotics for the eradication of Helicobacter pylori (H. pylori) in patients with chronic active gastritis with or without peptic ulcer disease., Methods: Seventy-five H. pylori-infected patients were randomized in a double-blind fashion to receive a 7-day treatment regimen consisting of: RAC, RAM, RCM, or RC (R=rabeprazole 20 mg b.d., A=amoxycillin 1 g b.d., C=clarithromycin 500 mg b.d., M=metronidazole 400 mg b.d.). Randomized patients were H. pylori-positive by gastric biopsy urease test, histology and 13C urea breath test (13C-UBT). H. pylori eradication was assessed by 13C-UBT, 4 and 8 wk after finishing treatment. Endoscopy with histology and culture for antibiotic sensitivity testing was performed pretreatment and if treatment failed., Results: On an intention-to-treat analysis, treatment success was: RCM 100%, RAC 95%, RAM 90%, and RC 63%. The most common side effects were loose stools, headache, and taste disturbance, but there were no serious adverse events related to the study medication. The two patients failing RAM treatment had metronidazole-resistant strains before and after treatment. None of the pretreatment H. pylori isolates from six patients failing RC were clarithromycin resistant, but three of five successfully cultured posttreatment had developed clarithromycin resistance., Conclusion: Rabeprazole-based triple therapy with two antibiotics for 1 wk is safe and effective in eradicating H. pylori. Dual therapy with clarithromycin is less successful, and the majority of treatment failures develop clarithromycin resistance.
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- 1998
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28. Proton pump inhibitors. Pharmacology and rationale for use in gastrointestinal disorders.
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Richardson P, Hawkey CJ, and Stack WA
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- Animals, Enzyme Inhibitors adverse effects, Humans, Enzyme Inhibitors therapeutic use, Gastrointestinal Diseases drug therapy, Proton Pump Inhibitors
- Abstract
Proton pump inhibitors (PPIs) are drugs which irreversibly inhibit proton pump (H+/K+ ATPase) function and are the most potent gastric acid-suppressing agents in clinical use. There is now a substantial body of evidence showing improved efficacy of PPIs over the histamine H2 receptor antagonists and other drugs in acid-related disorders. Omeprazole 20 mg/day, lansoprazole 30 mg/day, pantoprazole 40 mg/day or rabeprazole 20 mg/day for 2 to 4 weeks are more effective than standard doses of H2-receptor antagonists in healing duodenal and gastric ulcers. Patients with gastric ulcers should receive standard doses of PPIs as for duodenal ulcers but for a longer time period (4 to 8 weeks). There is no conclusive evidence to support the use of a particular PPI over another for either duodenal or gastric ulcer healing. For Helicobacter pylori-positive duodenal ulceration, a combination of a PPI and 2 antibacterials will eradicate H. pylori in over 90% of cases and significantly reduce ulcer recurrence. Patients with H. pylori-positive gastric ulcers should be managed similarly. PPIs also have efficacy advantages over ranitidine and misoprostol and are better tolerated than misoprostol in patients taking nonsteroidal anti-inflammatory drugs (NSAIDs). In endoscopically proven gastro-oesophageal reflux disease, standard daily doses of the PPIs are more effective than H2-receptor antagonists for healing, and patients should receive a 4 to 8 week course of treatment. For severe reflux, with ulceration and/or stricture formation, a higher dose regimen (omeprazole 40 mg, lansoprazole 60 mg, pantoprazole 80 mg or rabeprazole 40 mg daily) appears to yield better healing rates. There is little evidence that PPIs lead to resolution of Barrett's oesophagus or a reduction of subsequent adenocarcinoma development, but PPIs are indicated in healing of any associated ulceration. In Zollinger-Ellison syndrome, PPIs have become the treatment of choice for the management of gastric acid hypersecretion.
- Published
- 1998
- Full Text
- View/download PDF
29. Specific mediator-directed therapy for gastrointestinal diseases.
- Author
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Stack WA and Hawkey CJ
- Subjects
- Animals, Antibodies therapeutic use, Cyclosporine therapeutic use, Humans, Interleukin-1 antagonists & inhibitors, Interleukin-10 genetics, Interleukin-2 antagonists & inhibitors, Leukotriene Antagonists, Lipoxygenase Inhibitors, Mice, Mice, Knockout, Oligonucleotides, Antisense therapeutic use, Platelet Activating Factor antagonists & inhibitors, Prostaglandins therapeutic use, Reactive Oxygen Species physiology, Thromboxanes antagonists & inhibitors, Tumor Necrosis Factor-alpha antagonists & inhibitors, Tumor Necrosis Factor-alpha immunology, Cytokines antagonists & inhibitors, Gastrointestinal Diseases therapy
- Abstract
A number of inflammatory mediators--such as proinflammatory cytokines, lipid derived eicosanoids and reactive oxygen metabolites--are elevated in chronic bowel inflammation. Existing drugs for Crohn's disease and ulcerative colitis, for example aminosalicylates and corticosteroids, work at many sites in the inflammatory cascade to control disease activity. These drugs may be associated with significant side-effects and do not always control the disease. Therefore there is an impetus to develop treatments which are safer and more specific for bowel inflammation. Specific inhibitors of inflammatory mediators have recently become available and some have been shown to be effective in animal models of bowel inflammation. Although far fewer data are currently available on specific mediator-directed therapy of intestinal inflammation in humans, early clinical trials in inflammatory bowel disease have given mixed results. It remains to be determined whether or not this strategy of specific mediator inhibition is an alternative to current therapy for chronic bowel inflammation in humans.
- Published
- 1997
- Full Text
- View/download PDF
30. Nitric oxide donating compounds stimulate human colonic ion transport in vitro.
- Author
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Stack WA, Filipowicz B, and Hawkey CJ
- Subjects
- Colon drug effects, Humans, Intestinal Mucosa drug effects, Intestinal Mucosa metabolism, Nitric Oxide antagonists & inhibitors, Nitric Oxide pharmacology, Penicillamine metabolism, S-Nitroso-N-Acetylpenicillamine, Vasodilator Agents metabolism, Colon metabolism, Ion Transport drug effects, Nitroprusside metabolism, Penicillamine analogs & derivatives
- Abstract
Background: Nitric oxide (NO) has been recently implicated as a possible mediator of bowel inflammation and has also been shown to stimulate electrogenic chloride secretion in rat and guinea pig intestine. This study therefore investigated the effect on two NO donors, sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine (SNAP) on human colonic ion transport., Methods: Changes in short circuit current (delta SCC) in response to nitric oxide donating compounds were measured in muscle stripped normal human colon mounted in Ussing chambers. The ion species and intracellular mechanisms responsible for delta SCC evoked by SNP were investigated., Results: Basolateral SNP caused a progressive rise in delta SCC over the range 10(-7) to 10(-4)M (ED50 = 2.5 x 10(-5)M). SNAP 10(-4)M also evoked a qualitatively similar delta SCC compared with SNP 10(-4)M. Basolateral SNP evoked a greater delta SCC than apical and this was significantly attenuated by bumetanide 10(-4)M (52.9 +/- 10.1%) and in chloride free media (68.3 +/- 7.3%). delta SCC response to SNP was not significantly changed by basolateral 4-acetamido-4'-isothio-cyano-2,2'disulphonic acid stillbene (SITS 10(-3)M) an inhibitor of sodium/bicarbonate exchange, or apical amiloride 10(-5)M an inhibitor of sodium absorption. SNP induced delta SCC was also significantly reduced by piroxicam (mean (SEM)) 10(-5)M (57.9 (11.9)%), nordihydroguaretic acid 10(-4)M (48.0 (12.9)%), tetrodotoxin (TTX 10(-6)M, 52.3 (9.1)%), and practically abolished by TTX and piroxicam together (96.8 (3.3)%)., Conclusion: NO donors stimulate human colonic ion transport in vitro. For SNP, increased delta SCC is at least due in part to chloride secretion, and the response seems to be transduced through enteric nerves and by local prostanoid synthesis. This study provides evidence that NO may be another important mediator of ion transport in human colon.
- Published
- 1996
- Full Text
- View/download PDF
31. Regulation of ion transport by histamine in human colon.
- Author
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Keely SJ, Stack WA, O'Donoghue DP, and Baird AW
- Subjects
- Arachidonic Acid pharmacology, Cimetidine pharmacology, Colon drug effects, Eicosanoids metabolism, Histamine Agonists pharmacology, Histamine H2 Antagonists pharmacology, Humans, In Vitro Techniques, Intestinal Mucosa drug effects, Intestinal Mucosa metabolism, Ion Channels drug effects, Receptors, Histamine drug effects, Colon metabolism, Histamine physiology, Ion Channels metabolism
- Abstract
Histamine, added to the basolateral side of voltage clamped human colon in vitro, induced a rapid onset, transient inward short circuit current which was concentration dependent over the range 0.01-3 mM. This response was largely due to electrogenic chloride section since it was virtually abolished by bumetanide or by chloride replacement in the bathing solutions. Responses were unaffected by amiloride or acetazolamide. Neither the histamine H2 receptor agonist dimaprit (1 mM) nor the histamine H3 receptor agonist S-(+)-alpha-methyl histamine (1 mM) altered short circuit current. Responses to histamine were significantly reduced by the histamine H1 receptor antagonist mepyramine (1-10 microM) but not altered by the histamine H2 receptor antagonist cimetidine (100 microM) or by the histamine H3 receptor antagonist thioperamide (1 microM). Short circuit current responses to histamine were not altered by tetrodotoxin (1 microM). Piroxicam (10 microM) and nordihydroguaiaretic acid (100 microM) were without effect when used individually but significantly reduced responses to histamine when used simultaneously. These results indicate that histamine stimulates chloride secretion across human colonic epithelium by a mechanism which is mediated exclusively via histamine H1 receptors. This action does not involve intrinsic nerves but appears to be dependent upon eicosanoid synthesis.
- Published
- 1995
- Full Text
- View/download PDF
32. Immune regulation of human colonic electrolyte transport in vitro.
- Author
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Stack WA, Keely SJ, O'Donoghue DP, and Baird AW
- Subjects
- Antibodies, Anti-Idiotypic pharmacology, Bumetanide pharmacology, Diarrhea metabolism, Eosinophils metabolism, Humans, In Vitro Techniques, Ion Transport drug effects, Macrophages metabolism, Mast Cells metabolism, N-Formylmethionine Leucyl-Phenylalanine pharmacology, Neutrophils metabolism, Piroxicam pharmacology, Pyrilamine pharmacology, Stimulation, Chemical, Chlorides metabolism, Colon metabolism, Immune System physiology, Intestinal Mucosa metabolism
- Abstract
The role of lamina propria cells in regulating human colonic ion transport was investigated in vitro. Normal human colonic mucosae were mounted in Ussing chambers, and short circuit current changes (delta SCC) were monitored in response to immune cell activation. Anti-human immunoglobulin E (anti-IgE) and formyl-Methionyl-Leucyl-Phenylalanine (fMLP) were used to stimulate mast cells and phagocytes respectively. Anti-IgE (100 micrograms/ml) and fMLP (100 microM) evoked rapid onset, inward delta SCC (mean (SEM) max delta SCC 19.3 (2.8) and 29.4 (4.7) microA/0.63 cm2 respectively). A pharmacological approach was used to identify the charge carrying ion species and to characterise mediators involved in the SCC response. Responses to each secretagogue were significantly attenuated by bumetanide, indicating that the delta SCC was at least partly due to electrogenic chloride secretion. Piroxicam reduced the delta SCC to mast cell and phagocyte activation by 91.1 (3.4)% and 48.2 (25.2)% respectively, implicating eicosanoids as mediators of the responses. Mepyramine (100 microM) reduced the SCC responses to anti-IgE by 79.6 (12.0)% but did not significantly alter delta SCC responses to fMLP. Desensitisation to repeated anti-IgE or fMLP stimulation, and cross desensitisation between each of the stimuli, were features of immune cell activation. In summary, we have shown that activation of immune cells can stimulate electrogenic chloride secretion. Such events in vivo will result in gradient driven secretory diarrhoea, which may occur as a protective response to enteric-dwelling parasites, or as a feature of local bowel inflammation.
- Published
- 1995
- Full Text
- View/download PDF
33. Cytomegalovirus myocarditis following liver transplantation.
- Author
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Stack WA, Mulcahy HE, Fenelon L, and Hegarty JE
- Subjects
- Adult, Cytomegalovirus genetics, Cytomegalovirus Infections virology, DNA, Viral analysis, Echocardiography, Electrocardiography, Female, Humans, Opportunistic Infections virology, Polymerase Chain Reaction, Cytomegalovirus Infections diagnosis, Liver Transplantation, Myocarditis diagnosis, Opportunistic Infections diagnosis, Postoperative Complications diagnosis
- Abstract
Cytomegalovirus (CMV) infections are commonly found in patients on immunosuppressive therapy following liver transplantation. However, acute myocarditis is an extremely rare manifestation of CMV infection in this setting. We report the case of a patient who developed acute myocarditis with severe biventricular failure with a cardiac ejection fraction of less than 10%, 6 weeks following orthotopic liver transplantation. Systemic CMV infection was diagnosed on the basis of a clinical viraemia, the presence of CMV antigen in urine, blood, and throat swab, and an associated four-fold rise in serum antibody titres to CMV. A full recovery ensued following treatment with standard anti-cardiac failure therapy and a 10 day course of intravenous ganciclovir.
- Published
- 1994
- Full Text
- View/download PDF
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