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1.
Lancet ; 400(10359): 1195-1205, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36216006

RESUMO

BACKGROUND: Allopurinol is a urate-lowering therapy used to treat patients with gout. Previous studies have shown that allopurinol has positive effects on several cardiovascular parameters. The ALL-HEART study aimed to determine whether allopurinol therapy improves major cardiovascular outcomes in patients with ischaemic heart disease. METHODS: ALL-HEART was a multicentre, prospective, randomised, open-label, blinded-endpoint trial done in 18 regional centres in England and Scotland, with patients recruited from 424 primary care practices. Eligible patients were aged 60 years or older, with ischaemic heart disease but no history of gout. Participants were randomly assigned (1:1), using a central web-based randomisation system accessed via a web-based application or an interactive voice response system, to receive oral allopurinol up-titrated to a dose of 600 mg daily (300 mg daily in participants with moderate renal impairment at baseline) or to continue usual care. The primary outcome was the composite cardiovascular endpoint of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death. The hazard ratio (allopurinol vs usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis (excluding randomly assigned patients later found to have met one of the exclusion criteria). The safety analysis population included all patients in the modified intention-to-treat usual care group and those who took at least one dose of randomised medication in the allopurinol group. This study is registered with the EU Clinical Trials Register, EudraCT 2013-003559-39, and ISRCTN, ISRCTN32017426. FINDINGS: Between Feb 7, 2014, and Oct 2, 2017, 5937 participants were enrolled and then randomly assigned to receive allopurinol or usual care. After exclusion of 216 patients after randomisation, 5721 participants (mean age 72·0 years [SD 6·8], 4321 [75·5%] males, and 5676 [99·2%] white) were included in the modified intention-to-treat population, with 2853 in the allopurinol group and 2868 in the usual care group. Mean follow-up time in the study was 4·8 years (1·5). There was no evidence of a difference between the randomised treatment groups in the rates of the primary endpoint. 314 (11·0%) participants in the allopurinol group (2·47 events per 100 patient-years) and 325 (11·3%) in the usual care group (2·37 events per 100 patient-years) had a primary endpoint (hazard ratio [HR] 1·04 [95% CI 0·89-1·21], p=0·65). 288 (10·1%) participants in the allopurinol group and 303 (10·6%) participants in the usual care group died from any cause (HR 1·02 [95% CI 0·87-1·20], p=0·77). INTERPRETATION: In this large, randomised clinical trial in patients aged 60 years or older with ischaemic heart disease but no history of gout, there was no difference in the primary outcome of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death between participants randomised to allopurinol therapy and those randomised to usual care. FUNDING: UK National Institute for Health and Care Research.


Assuntos
Doença da Artéria Coronariana , Gota , Infarto do Miocárdio , Isquemia Miocárdica , Acidente Vascular Cerebral , Idoso , Alopurinol/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Feminino , Gota/tratamento farmacológico , Humanos , Masculino , Infarto do Miocárdio/tratamento farmacológico , Isquemia Miocárdica/tratamento farmacológico , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento , Reino Unido , Ácido Úrico
2.
Lancet ; 396(10264): 1745-1757, 2020 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-33181081

RESUMO

BACKGROUND: Febuxostat and allopurinol are urate-lowering therapies used to treat patients with gout. Following concerns about the cardiovascular safety of febuxostat, the European Medicines Agency recommended a post-licensing study assessing the cardiovascular safety of febuxostat compared with allopurinol. METHODS: We did a prospective, randomised, open-label, blinded-endpoint, non-inferiority trial of febuxostat versus allopurinol in patients with gout in the UK, Denmark, and Sweden. Eligible patients were 60 years or older, already receiving allopurinol, and had at least one additional cardiovascular risk factor. Those who had myocardial infarction or stroke in the previous 6 months or who had severe congestive heart failure or severe renal impairment were excluded. After a lead-in phase in which allopurinol dose was optimised towards achieving a serum urate concentration of less than 0·357 mmol/L (<6 mg/dL), patients were randomly assigned (1:1, with stratification according to previous cardiovascular events) to continue allopurinol (at the optimised dose) or start febuxostat at 80 mg/day, increasing to 120 mg/day if necessary to achieve the target serum urate concentration. The primary outcome was a composite of hospitalisation for non-fatal myocardial infarction or biomarker-positive acute coronary syndrome; non-fatal stroke; or cardiovascular death. The hazard ratio (HR) for febuxostat versus allopurinol in a Cox proportional hazards model (adjusted for the stratification variable and country) was assessed for non-inferiority (HR limit 1·3) in an on-treatment analysis. This study is registered with the EU Clinical Trials Register (EudraCT 2011-001883-23) and ISRCTN (ISRCTN72443728) and is now closed. FINDINGS: From Dec 20, 2011, to Jan 26, 2018, 6128 patients (mean age 71·0 years [SD 6·4], 5225 [85·3%] men, 903 [14·7%] women, 2046 [33·4%] with previous cardiovascular disease) were enrolled and randomly allocated to receive allopurinol (n=3065) or febuxostat (n=3063). By the study end date (Dec 31, 2019), 189 (6·2%) patients in the febuxostat group and 169 (5·5%) in the allopurinol group withdrew from all follow-up. Median follow-up time was 1467 days (IQR 1029-2052) and median on-treatment follow-up was 1324 days (IQR 870-1919). For incidence of the primary endpoint, on-treatment, febuxostat (172 patients [1·72 events per 100 patient-years]) was non-inferior to allopurinol (241 patients [2·05 events per 100 patient-years]; adjusted HR 0·85 [95% CI 0·70-1·03], p<0·0001). In the febuxostat group, 222 (7·2%) of 3063 patients died and 1720 (57·3%) of 3001 in the safety analysis set had at least one serious adverse event (with 23 events in 19 [0·6%] patients related to treatment). In the allopurinol group, 263 (8·6%) of 3065 patients died and 1812 (59·4%) of 3050 had one or more serious adverse events (with five events in five [0·2%] patients related to treatment). Randomised therapy was discontinued in 973 (32·4%) patients in the febuxostat group and 503 (16·5%) patients in the allopurinol group. INTERPRETATION: Febuxostat is non-inferior to allopurinol therapy with respect to the primary cardiovascular endpoint, and its long-term use is not associated with an increased risk of death or serious adverse events compared with allopurinol. FUNDING: Menarini, Ipsen, and Teijin Pharma Ltd.


Assuntos
Alopurinol/administração & dosagem , Doenças Cardiovasculares/complicações , Febuxostat , Supressores da Gota , Gota/tratamento farmacológico , Idoso , Dinamarca , Febuxostat/administração & dosagem , Febuxostat/efeitos adversos , Feminino , Supressores da Gota/administração & dosagem , Supressores da Gota/efeitos adversos , Hospitalização , Humanos , Masculino , Estudos Prospectivos , Suécia , Resultado do Tratamento , Reino Unido , Ácido Úrico/sangue
3.
Gastroenterology ; 152(2): 389-397.e2, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27845055

RESUMO

Autologous hematopoietic stem cell transplantation (HSCT) and mesenchymal stromal cell therapy have been proposed for patients with refractory Crohn's disease (CD) and fistulizing CD, respectively. Will these highly advanced techniques be available only for select patients, at specialized centers, or is further clinical development justified, with the aim of offering widespread, more definitive therapeutic options for often very difficult to treat disease? Patients with CD who are eligible for HSCT have typically been failed by most approved therapies, have undergone multiple surgeries, and have coped with years of disease activity and poor quality of life. The objective of HSCT is to immediately shut down the immune response and allow the transplanted stem cells to develop into self-tolerant lymphocytes. For patients with fistulizing CD, mesenchymal stromal cell therapy deposits MSCs locally, into fistulizing tracts, to down-regulate the local immune response and induce wound healing. Recent trials have produced promising results for HSCT and mesenchymal stromal cell therapy as alternatives to systemic therapies and antibiotics for patients with inflammatory bowel diseases, but are these immunotherapies ready for prime time?


Assuntos
Doença de Crohn/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Fístula Intestinal/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Doença de Crohn/complicações , Humanos , Doenças Inflamatórias Intestinais/terapia , Fístula Intestinal/etiologia , Tolerância a Antígenos Próprios , Cicatrização
4.
Digestion ; 92(2): 83-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26278889

RESUMO

BACKGROUND: REG3α has been recently shown to be a highly accurate biomarker for graft-versus-host-disease (GvHD). Given the unmet need of such biomarkers in Crohn's disease (CD) and the similarities between CD and GvHD, we aimed at investigating the role of serum REG3α as a diagnostic and prognostic biomarker in CD patients undergoing autologous hemopoetic stem cell transplantation (HSCT) in the multicenter Autologous Stem Cell Transplantation International Crohn's Disease (ASTIC) trial and to compare it to C-reactive protein (CRP). METHODS: Stored serum samples from the ASTIC trial were analyzed using a commercially available human PAP1 ELISA-kit to measure REG3α levels. CRP was available from prior analysis in the ASTIC trial. These levels were correlated with clinical and endoscopic disease activity as well as overall clinical and endoscopic outcome 1 year after autologous HSCT. RESULTS: One hundred thirty two serum samples were available for analysis. The mean concentration of REG3α was 101.8 ng/ml (95% CI 22.6-258.3). No significant elevation of REG3α was found among patients with active disease compared to those in remission (106.3 vs. 91.4). Patients with moderate to severe endoscopic disease activity showed substantially, although not significantly elevated REG3α levels compared to those in remission (95.4 vs. 52.4, p = 0.052). Baseline serum REG3α levels of patients without clinical or endoscopic remission 1 year after HSCT were not elevated compared to those in remission (63.1 vs. 66.9, and 68.4 vs. 59.2, respectively). In contrast, CRP was significantly elevated in patients with active disease compared to patients in remission (14.1 vs. 6.0 mg/dl, p = 0.032). In addition, CRP was elevated, although not significantly, in patients with severe endoscopic disease compared to those in endoscopic remission (18.7 vs. 4.1, p = 0.062). Furthermore, baseline CRP was reduced in patients with clinical and endoscopic remission after HSCT compared to those without remission, although not significantly (8.8 vs. 21.4, n.s. and 8.1 vs. 12.4, n.s.). CONCLUSION: Given the divergent findings compared to GvHD, we conclude that serum REG3α is not an accurate diagnostic and predictive biomarker in CD patients undergoing HSCT. In contrast, CRP is a valuable biomarker in order to differentiate active disease from remission. However, CRP does not seem to be of prognostic value for HSCT outcome.


Assuntos
Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Proteína C-Reativa/análise , Doença de Crohn/sangue , Doença de Crohn/diagnóstico , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/uso terapêutico , Lectinas Tipo C/sangue , Adulto , Biomarcadores/sangue , Colonoscopia , Doença de Crohn/terapia , Ciclofosfamida/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Feminino , Filgrastim/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Associadas a Pancreatite , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Transplante Autólogo , Adulto Jovem
5.
JAMA ; 314(23): 2524-34, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26670970

RESUMO

IMPORTANCE: Case reports and series suggest hematopoietic stem cell transplantation (HSCT) may benefit some patients with Crohn disease. OBJECTIVE: To evaluate the effect of autologous HSCT on refractory Crohn disease. DESIGN, SETTING, AND PARTICIPANTS: Parallel-group randomized clinical trial conducted in 11 European transplant units from July 2007 to September 2011, with follow-up through March 2013. Patients were aged 18 to 50 years with impaired quality of life from refractory Crohn disease not amenable to surgery despite treatment with 3 or more immunosuppressive or biologic agents and corticosteroids. INTERVENTIONS: All patients underwent stem cell mobilization before 1:1 randomization to immunoablation and HSCT (n = 23) or control treatment (HSCT deferred for 1 year [n = 22]). All were given standard Crohn disease treatment as needed. MAIN OUTCOMES AND MEASURES: Sustained disease remission at 1 year, a composite primary end point comprising clinical remission (Crohn Disease Activity Index (CDAI) <150 [range, 0-600]), no use of corticosteroids or immunosuppressive or biologic drugs for at least the last 3 months, and no endoscopic or radiological evidence of active (erosive) disease anywhere in the gastrointestinal (GI) tract. Secondary outcomes were individual components of the primary composite outcome and other measures of disease activity, laboratory results, quality of life and functional status, and GI tract imaging. RESULTS: Twenty-three patients underwent HSCT and 22 received standard Crohn disease treatment (controls). Sustained disease remission was achieved in 2 patients undergoing HSCT (8.7%) vs 1 control patient (4.5%) (absolute difference, 4.2% [95% CI, -14.2% to 22.6%]; P = .60). Fourteen patients undergoing HSCT (61%) vs 5 control patients (23%) had discontinued immunosuppressive or biologic agents or corticosteroids for at least 3 months (difference, 38.1% [95% CI, 9.3% to 59.3%]; P = .01). Ten vs 2 patients had a CDAI less than 150 (remission) at the final evaluation, 8 (34.8%) vs 2 (9.1%) for 3 or more months (difference, 25.7% [95% CI, 1.1% to 47.1%]; P = .052). Eight (34.8%) vs 2 (9.1%) patients were adjudicated free of active disease on endoscopy and radiology at final assessment (difference, 25.7% [95% CI, 1.1% to 47.1%]; P = .054). There were 76 serious adverse events in patients undergoing HSCT vs 38 in controls. One patient undergoing HSCT died. CONCLUSIONS AND RELEVANCE: Among adult patients with refractory Crohn disease not amenable to surgery who had impaired quality of life, HSCT, compared with conventional therapy, did not result in a statistically significant improvement in sustained disease remission at 1 year and was associated with significant toxicity. These findings do not support the widespread use of HSCT for patients with refractory Crohn disease. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00297193.


Assuntos
Doença de Crohn/terapia , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas/métodos , Adulto , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Indução de Remissão , Fatores de Tempo , Condicionamento Pré-Transplante/métodos , Transplante Autólogo , Resultado do Tratamento
6.
Health Psychol ; 43(2): 77-88, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38059932

RESUMO

OBJECTIVE: This trial explored the psychological and immunological effects of two brief interventions, targeting improving positive mood, administered to older adults immediately prior to influenza vaccination. The primary aim was to examine whether the interventions resulted in greater positive mood compared to usual care, and if so, which was superior. Secondary outcomes included antibody responses to vaccination and feasibility of collecting clinical outcome data (e.g., respiratory infections). METHOD: Six hundred and fifty-four older adults (65-85 years) participated in a three-arm, parallel, randomized controlled trial between September 2019 and May 2020. Immediately prior to receiving an adjuvanted trivalent influenza vaccine (Fluad, Seqirus UK Ltd), participants viewed one of two brief (15-min) video-based positive mood interventions (one fixed content, one allowing participant choice) or received usual care. State affect was measured immediately prior to, and following, intervention exposure or usual care. Antibody responses were measured prevaccination and 4 weeks postvaccination. Clinical outcomes were extracted from primary care records for 6 months following vaccination. RESULTS: Both interventions were equally effective at improving mood prior to vaccination compared to usual care. Antibody responses were highly robust with postvaccination seroprotection rates of > 88% observed for all vaccine strains. Antibody responses did not significantly differ between groups. Clinical outcome data were feasible to collect. CONCLUSIONS: Brief psychological interventions can improve mood prior to vaccination. However, altering antibody responses to highly immunogenic adjuvanted vaccines may require more targeted or prolonged interventions. The provision of choice did not notably enhance the interventions impact on mood or antibody outcomes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Vacinas contra Influenza , Influenza Humana , Idoso , Humanos , Adjuvantes Imunológicos , Afeto , Anticorpos Antivirais , Influenza Humana/prevenção & controle , Vacinação , Idoso de 80 Anos ou mais
7.
Health Technol Assess ; 28(18): 1-55, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38551218

RESUMO

Background: Allopurinol is a xanthine oxidase inhibitor that lowers serum uric acid and is used to prevent acute gout flares in patients with gout. Observational and small interventional studies have suggested beneficial cardiovascular effects of allopurinol. Objective: To determine whether allopurinol improves major cardiovascular outcomes in patients with ischaemic heart disease. Design: Prospective, randomised, open-label, blinded endpoint multicentre clinical trial. Setting: Four hundred and twenty-four UK primary care practices. Participants: Aged 60 years and over with ischaemic heart disease but no gout. Interventions: Participants were randomised (1 : 1) using a central web-based randomisation system to receive allopurinol up to 600 mg daily that was added to usual care or to continue usual care. Main outcome measures: The primary outcome was the composite of non-fatal myocardial infarction, non-fatal stroke or cardiovascular death. Secondary outcomes were non-fatal myocardial infarction, non-fatal stroke, cardiovascular death, all-cause mortality, hospitalisation for heart failure, hospitalisation for acute coronary syndrome, coronary revascularisation, hospitalisation for acute coronary syndrome or coronary revascularisation, all cardiovascular hospitalisations, quality of life and cost-effectiveness. The hazard ratio (allopurinol vs. usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis. Results: From 7 February 2014 to 2 October 2017, 5937 participants were enrolled and randomised to the allopurinol arm (n = 2979) or the usual care arm (n = 2958). A total of 5721 randomised participants (2853 allopurinol; 2868 usual care) were included in the modified intention-to-treat analysis population (mean age 72.0 years; 75.5% male). There was no difference between the allopurinol and usual care arms in the primary endpoint, 314 (11.0%) participants in the allopurinol arm (2.47 events per 100 patient-years) and 325 (11.3%) in the usual care arm (2.37 events per 100 patient-years), hazard ratio 1.04 (95% confidence interval 0.89 to 1.21); p = 0.65. Two hundred and eighty-eight (10.1%) participants in the allopurinol arm and 303 (10.6%) participants in the usual care arm died, hazard ratio 1.02 (95% confidence interval 0.87 to 1.20); p = 0.77. The pre-specified health economic analysis plan was to perform a 'within trial' cost-utility analysis if there was no statistically significant difference in the primary endpoint, so NHS costs and quality-adjusted life-years were estimated over a 5-year period. The difference in costs between treatment arms was +£115 higher for allopurinol (95% confidence interval £17 to £210) with no difference in quality-adjusted life-years (95% confidence interval -0.061 to +0.060). We conclude that there is no evidence that allopurinol used in line with the study protocol is cost-effective. Limitations: The results may not be generalisable to younger populations, other ethnic groups or patients with more acute ischaemic heart disease. One thousand six hundred and thirty-seven participants (57.4%) in the allopurinol arm withdrew from randomised treatment, but an on-treatment analysis gave similar results to the main analysis. Conclusions: The ALL-HEART study showed that treatment with allopurinol 600 mg daily did not improve cardiovascular outcomes compared to usual care in patients with ischaemic heart disease. We conclude that allopurinol should not be recommended for the secondary prevention of cardiovascular events in patients with ischaemic heart disease but no gout. Future work: The effects of allopurinol on cardiovascular outcomes in patients with ischaemic heart disease and co-existing hyperuricaemia or clinical gout could be explored in future studies. Trial registration: This trial is registered as EU Clinical Trials Register (EudraCT 2013-003559-39) and ISRCTN (ISRCTN 32017426). Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 11/36/41) and is published in full in Health Technology Assessment; Vol. 28, No. 18. See the NIHR Funding and Awards website for further award information.


The purpose of the ALL-HEART study was to determine whether giving allopurinol to people with ischaemic heart disease (also commonly known as coronary heart disease) would reduce their risk of having a heart attack, stroke or of dying from cardiovascular disease. Allopurinol is a medication usually given to patients with gout to prevent acute gout flares. It is not currently used to treat ischaemic heart disease. We randomly allocated people aged over 60 years with ischaemic heart disease to take up to 600 mg of allopurinol daily (in addition to their usual care) or to continue with their usual care. We then monitored participants for several years and recorded any major health events such as heart attacks, strokes and deaths. We obtained most of the follow-up data from centrally held electronic hospital admissions and death records, making the study easier for participants and more cost-efficient. We asked participants in both groups to complete questionnaires to assess their quality of life during the study. We also collected data to determine whether there was any economic benefit to the NHS of using allopurinol in patients with ischaemic heart disease. There was no difference in the risk of heart attacks, strokes or death from cardiovascular disease between the participants given allopurinol and those in the group continuing their usual care. We also found no difference in the risks of other cardiovascular events, deaths from any cause or quality-of-life measurements between the allopurinol and usual care groups. The results of the ALL-HEART study suggest that we should not recommend that allopurinol be given to people with ischaemic heart disease to prevent further cardiovascular events or deaths.


Assuntos
Síndrome Coronariana Aguda , Gota , Infarto do Miocárdio , Isquemia Miocárdica , Acidente Vascular Cerebral , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Alopurinol/uso terapêutico , Análise Custo-Benefício , Qualidade de Vida , Estudos Prospectivos , Ácido Úrico , Isquemia Miocárdica/tratamento farmacológico , Gota/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico
8.
Lancet Gastroenterol Hepatol ; 9(4): 333-345, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38340759

RESUMO

BACKGROUND: A previous controlled trial of autologous haematopoietic stem-cell transplantation (HSCT) in patients with refractory Crohn's disease did not meet its primary endpoint and reported high toxicity. We aimed to assess the safety and efficacy of HSCT with an immune-ablative regimen of reduced intensity versus standard of care in this patient population. METHODS: This open-label, multicentre, randomised controlled trial was conducted in nine National Health Service hospital trusts across the UK. Adults (aged 18-60 years) with active Crohn's disease on endoscopy (Simplified Endoscopic Score for Crohn's Disease [SES-CD] ulcer sub-score of ≥2) refractory to two or more classes of biological therapy, with no perianal or intra-abdominal sepsis or clinically significant comorbidity, were recruited. Participants were centrally randomly assigned (2:1) to either HSCT with a reduced dose of cyclophosphamide (intervention group) or standard care (control group). Randomisation was stratified by trial site by use of random permuted blocks of size 3 and 6. Patients in the intervention group underwent stem-cell mobilisation (cyclophosphamide 1 g/m2 with granulocyte colony-stimulating factor (G-CSF) 5 µg/kg) and stem-cell harvest (minimum 2·0 × 106 CD34+ cells per kg), before conditioning (fludarabine 125 mg/m2, cyclophosphamide 120 mg/kg, and rabbit anti-thymocyte globulin [thymoglobulin] 7·5 mg/kg in total) and subsequent stem-cell reinfusion supported by G-CSF. Patients in the control group continued any available conventional, biological, or nutritional therapy. The primary outcome was absence of endoscopic ulceration (SES-CD ulcer sub-score of 0) without surgery or death at week 48, analysed in the intention-to-treat population by central reading. This trial is registered with the ISRCTN registry, 17160440. FINDINGS: Between Oct 18, 2018, and Nov 8, 2019, 49 patients were screened for eligibility, of whom 23 (47%) were randomly assigned: 13 (57%) to the intervention group and ten (43%) to the control group. In the intervention group, ten (77%) participants underwent HSCT and nine (69%) reached 48-week follow-up; in the control group, nine (90%) reached 48-week follow-up. The trial was halted in response to nine reported suspected unexpected serious adverse reactions in six (46%) patients in the intervention group, including renal failure due to proven thrombotic microangiopathy in three participants and one death due to pulmonary veno-occlusive disease. At week 48, absence of endoscopic ulceration without surgery or death was reported in three (43%) of seven participants in the intervention group and in none of six participants in the control group with available data. Serious adverse events were more frequent in the intervention group (38 in 13 [100%] patients) than in the control group (16 in four [40%] patients). A second patient in the intervention group died after week 48 of respiratory and renal failure. INTERPRETATION: Although HSCT with an immune-ablative regimen of reduced intensity decreased endoscopic disease activity, significant adverse events deem this regimen unsuitable for future clinical use in patients with refractory Crohn's disease. FUNDING: Efficacy and Mechanism Evaluation Programme, a Medical Research Council and National Institute for Health Research partnership.


Assuntos
Doença de Crohn , Transplante de Células-Tronco Hematopoéticas , Insuficiência Renal , Adulto , Humanos , Doença de Crohn/tratamento farmacológico , Padrão de Cuidado , Medicina Estatal , Úlcera/etiologia , Resultado do Tratamento , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Ciclofosfamida/efeitos adversos , Fator Estimulador de Colônias de Granulócitos/uso terapêutico
9.
Dig Dis Sci ; 57(6): 1624-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22327240

RESUMO

INTRODUCTION: Interpretation of video capsule data is time-consuming. Olympus capsule endoscopy (CE) software systems are equipped with auto-speed-adjusted and express-selected playback modes and overview function in an effort to reduce reading times. The clinical efficacy of these new playback features is unknown. Our objective was to evaluate the diagnostic yield and reading times of these new playback features. METHODS: This was a retrospective cohort study involving two experienced CE readers who analysed the CE procedures using either overview with express-selected or overview with auto-speed-adjusted modes. All CE videos were read blinded using Olympus Endocapsule software at 15 frames per second. The findings were then compared with those obtained when the CE procedures were read with conventional methods. RESULTS: Seventy patients (36 male, 34 female) with a mean age of 51 ± 22 years were included in the study. Clinically significant findings were found for 40/70 (57%) patients. Use of overview function alone resulted in recognition of 32/40 (80%) clinically significant findings; when overview function was combined with express-selected or auto-speed-adjusted methods 39/40 (97.5%) clinically significant findings were recognised. The average reading time for overview with auto-speed-adjusted mode (34 ± 10 min) was significantly (p = 0.001) more than for overview with express-selected mode (19 ± 5 min). CONCLUSIONS: The reading time for overview with express-selected mode was significantly lower than for overview with auto-speed-adjusted mode, with few unrecognised clinically significant lesions. These new playback systems can efficaciously reduce reading times of CE but need further evaluation in prospective multicentre studies.


Assuntos
Automação , Endoscopia por Cápsula/métodos , Competência Clínica , Gastroenteropatias/diagnóstico , Adulto , Idoso , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
10.
Rheumatol Adv Pract ; 6(3): rkac086, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36407800

RESUMO

Objective: The aim was to test the feasibility of a randomized controlled trial exploring whether omega-3 fatty acid supplementation limits gout flares during treat-to-target urate-lowering treatment (T2T-ULT). Methods: Adults with at least one gout flare in the past 12 months and serum urate (SU) ≥360 µmol/l were recruited from general practices (primary method) and randomly assigned 1:1 to receive omega-3 fatty acid supplementation (4 g/day) or placebo for 28 weeks. At week 5, participants began T2T-ULT. The primary outcome was drop-out rate. Secondary outcomes were recruitment rate, outcome data completeness, the number, severity and duration of gout flares between weeks 5 and 28, and study drug compliance. Results: Ninety-five per cent of randomized participants (n = 60) completed all study visits. The primary method recruitment rate was 2.2%. Fifty and 42 participants achieved SU < 360 and 300 µmol/l (6 and 5 mg/dl), respectively. The number of gout flares [median (interquartile range): active 1 (0-2) and placebo 1 (0-2)], flare duration [mean (s.d.): active 7.00 (4.52) days and placebo 7.06 (8.14) days] and time to first flare [hazard ratio (95% CI) 0.97 (0.50, 1.86)] were comparable between both arms. Study drug compliance was high and comparable in both arms [median (interquartile range) returned capsule count: active 57 (26-100) and placebo 58 (27-154)]; red blood cell omega-3 fatty acid index increased twofold in the active arm and remained unchanged in the control arm. Conclusion: The study demonstrated feasibility and provided useful metrics for conducting a community-based gout flare prophylaxis trial. Study registration: ISRCTN; https://www.isrctn.com/; ISRCTN79392964.

11.
Trials ; 23(1): 140, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35164864

RESUMO

BACKGROUND: The Helicobacter Eradication Aspirin Trial (HEAT) is a multicentre, double blind, randomised controlled trial investigating whether Helicobacter (H.) pylori eradication reduces hospitalisation for peptic ulcer bleeding. Recruited participants were aged 60 and over and taking aspirin (≤325 mg daily) for at least four months prior to consent. Based on results of a pilot study, a sample size calculation predicted 6600 H. pylori-positive randomised participants would be required, from 33,000 volunteers, recruited from 170,000 invited patients. Methodology was therefore designed for recruitment of large numbers of patients from primary care using a novel electronic search tool, automated mail-out and electronic follow-up. Recruitment started in 2012 and completed in 2017. METHODS: All participants were recruited from GP practices, with assistance from the UK Clinical Research Network (UKCRN). H. pylori-positive participants were randomised to one week of eradication treatment or placebo. Recruitment was managed using a bespoke web-based database that communicated directly with a programmed search tool downloaded at participating practices. The primary endpoint is hospitalisation due to peptic ulcer bleeding. The trial will end when 87 adjudicated events have occurred, identified from searches of GP databases, review of secondary care admission data and mortality data, and reported events from randomised participants and GPs. RESULTS: HEAT has recruited participants from 1208 GP practices across the UK. Of the 188,875 invitation letters sent, 38,771 returned expressions of interest. Of these, 30,166 patients were consented to the trial, of whom 5355 H. pylori-positive participants (17.8% of those consented) were randomised. Mean age at consent was 73.1 ± 6.9 (SD) years and 72.2% of participants were male. Of the randomised (H. pylori-positive) participants, 531 have died (as of 17 Sep 2020); none of the deaths was due to trial treatment. CONCLUSION: The HEAT trial methodology has demonstrated that recruitment of large numbers of patients from primary care is attainable, with the assistance of the UKCRN, and could be applied to other clinical outcomes studies. TRIAL REGISTRATION: ClinicalTrials.gov ; registration number NCT01506986 . Registered on 10 Jan 2012.


Assuntos
Aspirina , Helicobacter , Idoso , Aspirina/efeitos adversos , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Atenção Primária à Saúde , Resultado do Tratamento
12.
Trials ; 23(1): 331, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35449015

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is a very common long-term condition and powerful risk factor for cardiovascular disease (CVD). Low-dose aspirin is of proven benefit in the secondary prevention of myocardial infarction (MI) and stroke in people with pre-existing CVD. However, in people without CVD, the rates of MI and stroke are much lower, and the benefits of aspirin in the primary prevention of CVD are largely balanced by an increased risk of bleeding. People with CKD are at greatly increased risk of CVD and so the absolute benefits of aspirin are likely to be greater than in lower-risk groups, even if the relative benefits are the same. Post hoc evidence suggests the relative benefits may be greater in the CKD population but the risk of bleeding may also be higher. A definitive study of aspirin for primary prevention in this high-risk group, recommended by the National Institute for Health and Care Excellence (NICE) in 2014, has never been conducted. The question has global significance given the rising burden of CKD worldwide and the low cost of aspirin. METHODS: ATTACK is a pragmatic multicentre, prospective, randomised, open-label, blinded endpoint adjudication superiority trial of aspirin 75 mg daily vs. standard care for the primary prevention of CVD in 25,210 people aged 18 years and over with CKD recruited from UK Primary Care. Participants aged 18 years and over with CKD (GFR category G1-G4) will be identified in Primary Care and followed up using routinely collected data and annual questionnaires for an average of 5 years. The primary outcome is the time to first major vascular event (composite of non-fatal MI, non-fatal stroke and cardiovascular death [excluding confirmed intracranial haemorrhage and other fatal cardiovascular haemorrhage]). Deaths from other causes (including fatal bleeding) will be treated as competing events. The study will continue until 1827 major vascular events have occurred. The principal safety outcome is major intracranial and extracranial bleeding; this is hypothesised to be increased in those randomised to take aspirin. The key consideration is then whether and to what extent the benefits of aspirin from the expected reduction in CVD events exceed the risks of major bleeding. DISCUSSION: This will be the first definitive trial of aspirin for primary CVD prevention in CKD patients. The research will be of great interest to clinicians, guideline groups and policy-makers, in the UK and globally, particularly given the high and rising prevalence of CKD that is driven by population ageing and epidemics of obesity and diabetes. The low cost of aspirin means that a positive result would be of relevance to low- and middle-income countries and the impact in the developed world less diluted by any inequalities in health care access. TRIAL REGISTRATION: ISRCTN: ISRCTN40920200 . EudraCT: 2018-000644-26 . CLINICALTRIALS: gov: NCT03796156.


Assuntos
Doenças Cardiovasculares , Infarto do Miocárdio , Insuficiência Renal Crônica , Acidente Vascular Cerebral , Adolescente , Adulto , Aspirina/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/prevenção & controle , Feminino , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Humanos , Masculino , Estudos Multicêntricos como Assunto , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/prevenção & controle , Inibidores da Agregação Plaquetária/efeitos adversos , Prevenção Primária/métodos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico , Acidente Vascular Cerebral/tratamento farmacológico
13.
Clin Gastroenterol Hepatol ; 9(8): 684-687.e1, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21642015

RESUMO

BACKGROUND & AIMS: Fat wrapping and mesenteric hypertrophy are characteristics of Crohn's disease (CD). In patients with CD, mesenteric adipose tissue releases higher levels of adiponectin, which could up-regulate production of tumor necrosis factor-α and increase the risk for aggressive disease. We investigated whether a higher ratio of visceral to subcutaneous fat was associated with complicated (fistulating or stricturing) CD. METHODS: We identified patients with a confirmed diagnosis of CD who had computed tomography scans of their abdomens (n = 50). Areas of subcutaneous and visceral fat were measured in 1 cross-sectional scan that was taken at the level of the umbilicus. The mesenteric fat index (MFI), defined as the ratio of areas of visceral to subcutaneous fat, was compared between patients with complicated (strictures and fistulas) and inflammatory CD. RESULTS: The mean age of the patients with complications (n = 29) was 49.3 ± 15.6 years, and in patients with inflammatory CD (n = 21) it was 37.7 ± 19.1 years. The MFI was significantly higher (P = .001) in patients with complicated disease (0.67 ± 0.29) than in those with uncomplicated disease (0.23 ± 0.10) and was the only variable that remained significantly different on multivariate analysis. The area under the receiver operating curve for the MFI was 0.95 (95% confidence interval, 0.89-1.0), and an MFI of 0.29 identified patients with complicated CD with 93% sensitivity and 81% specificity. CONCLUSIONS: A high ratio of areas of visceral to subcutaneous fat (MFI) is a marker of aggressive CD. Further studies are needed to determine the roles of adipose tissue in pathogenesis of CD.


Assuntos
Gordura Abdominal/patologia , Biomarcadores , Distribuição da Gordura Corporal/métodos , Doença de Crohn/diagnóstico , Doença de Crohn/patologia , Gordura Subcutânea/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Abdominal , Tomografia Computadorizada por Raios X
15.
BMC Microbiol ; 9: 28, 2009 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-19193236

RESUMO

BACKGROUND: Campylobacter jejuni, the commonest cause of bacterial diarrhoea worldwide, can also induce colonic inflammation. To understand how a previously identified heat stable component contributes to pro-inflammatory responses we used microarray and real-time quantitative PCR to investigate the transcriptional response to a boiled cell extract of Campylobacter jejuni NCTC 11168. RESULTS: RNA was extracted from the human colonocyte line HCA-7 (clone 29) after incubation for 6 hours with Campylobacter jejuni boiled cell extract and was used to probe the Affymetrix Human Genome U133A array. Genes differentially affected by Campylobacter jejuni boiled cell extract were identified using the Significance Score algorithm of the Bioconductor software suite and further analyzed using the Ingenuity Pathway Analysis program. The chemokines CCL20, CXCL3, CXCL2, Interleukin 8, CXCL1 and CXCL6 comprised 6 of the 10 most highly up-regulated genes, all with Significance Scores > or = 10. Members of the Tumor Necrosis Factor alpha/Nuclear Factor-kappaB super-family were also significantly up-regulated and involved in the most significantly regulated signalling pathways (Death receptor, Interleukin 6, Interleukin 10, Toll like receptor, Peroxisome Proliferator Activated Receptor-gamma and apoptosis). Ingenuity Pathway Analysis also identified the most affected functional gene networks such as cell movement, gene expression and cell death. In contrast, down-regulated genes were predominantly concerned with structural and metabolic functions. CONCLUSION: A boiled cell extract of Campylobacter jejuni has components that can directly switch the phenotype of colonic epithelial cells from one of resting metabolism to a pro-inflammatory one, particularly characterized by increased expression of genes for leukocyte chemoattractant molecules.


Assuntos
Campylobacter jejuni/química , Campylobacter jejuni/imunologia , Fatores Quimiotáticos/imunologia , Colo/imunologia , Células Epiteliais/imunologia , Perfilação da Expressão Gênica , Linhagem Celular , Quimiocinas/biossíntese , Fatores Quimiotáticos/isolamento & purificação , Colo/citologia , Regulação para Baixo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/imunologia , Regulação para Cima
16.
Scand J Gastroenterol ; 44(1): 85-92, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18821132

RESUMO

OBJECTIVE: To evaluate whether there is any appreciable difference in imaging characteristics between high-resolution magnification white-light endoscopy (WLE-Z) and narrow-band imaging (NBI-Z) in Barrett's oesophagus (BE) and if this translates into superior prediction of histology. MATERIAL AND METHODS: This was a prospective single-centre study involving 21 patients (75 areas, corresponding NBI-Z and WLE-Z images) with BE. Mucosal patterns (pit pattern and microvascular morphology) were evaluated for their image quality on a visual analogue scale (VAS) of 1-10 by five expert endoscopists. The endoscopists then predicted mucosal morphology based on four subtypes which can be visualized in BE. Type A: round pits, regular microvasculature; type B: villous/ridge pits, regular microvasculature; type C: absent pits, regular microvasculature; type D: distorted pits, irregular microvasculature. The sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV) and accuracy (Acc) were then compared with the final histopathological analysis and the interobserver variability calculated. RESULTS: The overall pit and microvasculature quality was significantly higher for NBI-Z, pit: NBI-Z=6, WLE-Z=4.5, p < 0.001; microvasculature: NBI-Z=7.3, WLE-Z=4.9, p < 0.001. This translated into a superior prediction of histology (Sn: NBI-Z: 88.9, WLE-Z: 71.9, p < 0.001). For the prediction of dysplasia, NBI-Z was superior to WLE-Z (chi(2)=10.3, p < 0.05). The overall kappa agreement among the five endoscopists for NBI-Z and WLE-Z, respectively, was 0.59 and 0.31 (p < 0.001). CONCLUSIONS: NBI-Z is superior to WLE-Z in the prediction of histology in BE, with good reproducibility. This novel imaging modality could be an important tool for surveillance of patients with BE.


Assuntos
Esôfago de Barrett/patologia , Esofagoscopia/métodos , Esôfago/patologia , Aumento da Imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/diagnóstico , Esôfago/irrigação sanguínea , Feminino , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador , Luz , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/diagnóstico , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade
17.
Clin Drug Investig ; 29(10): 677-87, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19715384

RESUMO

BACKGROUND AND OBJECTIVE: Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for the treatment of pain in rheumatic disorders and chronic pain syndromes. Their use is, however, limited by gastrointestinal (GI) toxicity, including upper GI symptoms, ulcers and related complications. Using data from the NASA/SPACE studies, we have reviewed the efficacy and tolerability of esomeprazole (20 or 40 mg once daily) in the management (i.e. short-term resolution plus long-term prevention of relapse) of upper GI symptoms in users of continuous daily NSAIDs. METHODS: The NASA/SPACE programme comprised four double-blind, placebo-controlled studies in NSAID users. Two studies evaluated the efficacy of esomeprazole for upper GI symptom relief over 4 weeks. Those patients with symptom relief were then enrolled into a further two studies that assessed efficacy over 6 months. RESULTS: In the 4-week studies, more patients in the esomeprazole groups achieved relief from upper GI symptoms at week 4 compared with placebo (p<0.05). The proportion of patients with symptom relapse at 6 months was lower with esomeprazole 20 mg and 40 mg than with placebo (p

Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Esomeprazol/uso terapêutico , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/tratamento farmacológico , Inibidores da Bomba de Prótons/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Ácido Gástrico/metabolismo , Gastroenteropatias/epidemiologia , Helicobacter pylori , Humanos , Estimativa de Kaplan-Meier , Ensaios Clínicos Controlados Aleatórios como Assunto , Prevenção Secundária , Estômago/microbiologia , Resultado do Tratamento
18.
Trials ; 20(1): 467, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31362765

RESUMO

BACKGROUND: Acute gastrointestinal (GI) bleeding is an important cause of mortality worldwide. Bleeding can occur from the upper or lower GI tract, with upper GI bleeding accounting for most cases. The main causes include peptic ulcer/erosive mucosal disease, oesophageal varices and malignancy. The case fatality rate is around 10% for upper GI bleeding and 3% for lower GI bleeding. Rebleeding affects 5-40% of patients and is associated with a four-fold increased risk of death. Tranexamic acid (TXA) decreases bleeding and the need for blood transfusion in surgery and reduces death due to bleeding in patients with trauma and postpartum haemorrhage. It reduces bleeding by inhibiting the breakdown of fibrin clots by plasmin. Due to the methodological weaknesses and small size of the existing trials, the effectiveness and safety of TXA in GI bleeding is uncertain. The Haemorrhage ALleviation with Tranexamic acid - Intestinal system (HALT-IT) trial aims to provide reliable evidence about the effects of TXA in acute upper and lower GI bleeding. METHODS: The HALT-IT trial is an international, randomised, double-blind, placebo-controlled trial of tranexamic acid in 12,000 adults (increased from 8000) with acute upper or lower GI bleeding. Eligible patients are randomly allocated to receive TXA (1-g loading dose followed by 3-g maintenance dose over 24 h) or matching placebo. The main analysis will compare those randomised to TXA with those randomised to placebo on an intention-to-treat basis, presenting the results as effect estimates (relative risks) and confidence intervals. The primary outcome is death due to bleeding within 5 days of randomisation and secondary outcomes are: rebleeding; all-cause and cause-specific mortality; thromboembolic events; complications; endoscopic, radiological and surgical interventions; blood transfusion requirements; disability (defined by a measure of patient's self-care capacity); and number of days spent in intensive care or high-dependency units. Subgroup analyses for the primary outcome will consider time to treatment, location of bleeding, cause of bleed and clinical Rockall score. DISCUSSION: We present the statistical analysis of the HALT-IT trial. This plan was published before the treatment allocation was unblinded. TRIAL REGISTRATION: Current Controlled Trials, ID: ISRCTN11225767. Registered on 3 July 2012; Clinicaltrials.gov, ID: NCT01658124. Registered on 26 July 2012.


Assuntos
Antifibrinolíticos/uso terapêutico , Hemorragia Gastrointestinal/tratamento farmacológico , Ácido Tranexâmico/uso terapêutico , Antifibrinolíticos/efeitos adversos , Interpretação Estatística de Dados , Método Duplo-Cego , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/mortalidade , Humanos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Ácido Tranexâmico/efeitos adversos , Resultado do Tratamento
19.
Clin Gastroenterol Hepatol ; 6(5): 536-44, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18242145

RESUMO

BACKGROUND & AIMS: The selective cyclooxygenase-2 inhibitor lumiracoxib has been shown to reduce endoscopically detected ulcers and ulcer complications in the upper gastrointestinal tract compared with nonselective nonsteroidal anti-inflammatory drugs. We investigated whether lumiracoxib would reduce small-bowel injury compared with naproxen plus omeprazole. METHODS: Healthy volunteers were randomized to receive lumiracoxib 100 mg once daily, naproxen 500 mg twice daily plus omeprazole 20 mg once daily, or placebo in a 16-day double-blind, parallel-group study. Small-bowel mucosal injury and inflammation were assessed by video capsule endoscopy, the lactulose:L-rhamnose permeability assessment, and the fecal calprotectin test. RESULTS: Of 152 randomized subjects, 139 completed the study with valid video capsule endoscopies (lumiracoxib, n = 47; naproxen plus omeprazole, n = 45; placebo, n = 47). Compared with placebo, an increased number of subjects on naproxen plus omeprazole had small-bowel mucosal breaks (77.8% vs 40.4%, P < .001), with increased permeability (P = .023) and increased fecal calprotectin (increase, 96.8 vs 14.5 mg/kg for placebo; P < .001). With lumiracoxib, 27.7% of subjects had small-bowel mucosal breaks (P = .196 vs placebo; P < .001 vs naproxen), there was no increase in permeability (P = .157 vs placebo; P = .364 vs naproxen), and no increase in fecal calprotectin (-5.7 mg/kg; P = .377 vs placebo; P < .001 vs naproxen). CONCLUSIONS: As assessed by 3 different measures, acute small-bowel injury on lumiracoxib treatment is less frequent than with naproxen plus omeprazole and similar to placebo.


Assuntos
Inibidores de Ciclo-Oxigenase/efeitos adversos , Diclofenaco/análogos & derivados , Intestino Delgado/efeitos dos fármacos , Naproxeno/efeitos adversos , Omeprazol/efeitos adversos , Úlcera/induzido quimicamente , Administração Oral , Adulto , Idoso , Cápsulas Endoscópicas , Estudos Cross-Over , Inibidores de Ciclo-Oxigenase/administração & dosagem , Diclofenaco/administração & dosagem , Diclofenaco/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Endoscopia Gastrointestinal/métodos , Feminino , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Masculino , Pessoa de Meia-Idade , Naproxeno/administração & dosagem , Omeprazol/administração & dosagem , Probabilidade , Valores de Referência , Medição de Risco , Úlcera/patologia
20.
Cell Signal ; 19(5): 1071-80, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17254749

RESUMO

Cullin-based E3 ligases are a large family of ubiquitin ligases with diverse cellular functions. They are composed of one of six mammalian cullin homologues, the Ring finger containing protein Roc1/Rbx1 and cullin homologue-specific adapter and substrate recognition subunits. To be active, cullin-based ligases require the covalent modification of a conserved lysine residue in the cullin protein with the ubiquitin-like protein Nedd8. To characterize this family of E3 ligases in intact cells, we generated a cell line with tetracycline-inducible expression of a dominant-negative mutant of the Nedd8-conjugating enzyme Ubc12, a reported inhibitor of cullin neddylation. Using this cell line, we demonstrate that the substrate recognition subunit Skp2 and the adaptor protein Skp1 are subject to Ubc12-dependent autoubiquitination and degradation. In contrast, cullin protein stability is not regulated by neddylation in mammalian cells. We also provide evidence that Cul1 and Cul3, as well as their associated substrate recognition subunits Skp2 and Keap1, respectively, homooligomerize in intact cells, suggesting that cullin-based ligases are dimeric. Cul3, but not Cul1 homooligomerization is dependent on substrate recognition subunit dimer formation. As shown for other E3 ubiquitin ligases, dimerization may play a role in regulating the activity of cullin-based E3 ligases.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Culina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Proteínas de Transporte , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p27 , Dimerização , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch , Camundongos , Proteína NEDD8 , Proteínas Quinases Associadas a Fase S/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Tetraciclina/farmacologia , Fatores de Transcrição/metabolismo , Ubiquitinas/metabolismo
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