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31.
Don Hayes Jr. Sylvester M. Black Joseph D. Tobias Heidi M. Mansour Bryan A. Whitson 《COPD》2016,13(1):50-56
Introduction: Prevalence of pulmonary hypertension (PH) and its influence on survival in chronic obstructive pulmonary disease (COPD) are not well studied in the lung allocation score (LAS) era.Methods: The UNOS database was queried from 2005 to 2013 to identify first-time adult lung transplant candidates with COPD who were tracked from wait list entry date until death or censoring to determine both prevalence and influence of PH. Using right heart catheterization measurements, mild PH was defined as mean pulmonary artery pressure (mPAP) ≥ 25 mmHg and severe ≥ 35 mmHg.Results: Of 1315 COPD candidates not transplanted, 1243 were used for survival analysis using Cox proportional hazards models, and 1010 (mild PH) and 244 (severe PH) were used for propensity score matching, respectively. A total of 52% (652) of subjects had PH mPAP ≥ 25 mmHg. Univariate analysis revealed significant differences in survival for mild PH (HR = 1.769; 95% CI: 1.331, 2.351; p < 0.001) and severe PH (HR = 3.271; 95% CI: 2.311, 4.630; p < 0.001). Kaplan–Meier survival function demonstrated significant disparities for mild PH (Log-rank test: Chi-square1: 15.87, p < 0.0001) and severe PH (Log-rank test: Chi-square1: 50.13, p < 0.0001). Multivariate Cox models identified significant risk for death for mild PH (HR = 1.987; 95% CI: 1.484, 2.662; p < 0.001) and severe PH (HR = 3.432; 95% CI: 2.410, 4.888; p < 0.001). Propensity score matching confirmed increased mortality hazard associated with mild PH (HR = 2.280; 95% CI: 1.425, 3.649; p = 0.001) and severe PH (HR = 7.000; 95% CI: 2.455, 19.957; p < 0.001).Conclusions: PH is highly prevalent in advanced COPD and associated with a significantly higher risk for mortality. 相似文献
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Hendrika J. Bekema Steven MacLennan Mari Imamura Thomas B.L. Lam Fiona Stewart Neil Scott Graeme MacLennan Sam McClinton T.R. Leyshon Griffiths Andreas Skolarikos Sara J. MacLennan Richard Sylvester Börje Ljungberg James N’Dow 《European urology》2013
Context
Controversy remains over whether adrenalectomy and lymph node dissection (LND) should be performed concomitantly with radical nephrectomy (RN) for locally advanced renal cell carcinoma (RCC) cT3–T4N0M0.Objective
To systematically review all relevant literature comparing oncologic, perioperative, and quality-of-life (QoL) outcomes for locally advanced RCC managed with RN with or without concomitant adrenalectomy or LND.Evidence acquisition
Relevant databases were searched up to August 2012. Randomised controlled trials (RCTs) and comparative studies were included. Outcome measures were overall survival, QoL, and perioperative adverse effects. Risks of bias (RoB) were assessed using Cochrane RoB tools. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach.Evidence synthesis
A total of 3658 abstracts and 252 full-text articles were screened. Eight studies met the inclusion criteria: six LNDs (one RCT and five nonrandomised studies [NRSs]) and two adrenalectomies (two NRSs). RoB was high across the evidence base, and the quality of evidence from outcomes ranged from moderate to very low. Meta-analyses were not undertaken because of diverse study designs and data heterogeneity. There was no significant difference in survival between the groups, even though 5-yr overall survival appears better for the RN plus LND group compared with the no-LND group in one randomised study. There was no evidence of a difference in adverse events between the RN plus LND and no-LND groups. No studies reported QoL outcomes. There was no evidence of an oncologic difference between the RN with adrenalectomy and RN without adrenalectomy groups. No studies reported adverse events or QoL outcomes.Conclusions
There is insufficient evidence to draw any conclusions on oncologic outcomes for patients having concomitant LND or ipsilateral adrenalectomy compared with patients having RN alone for cT3–T4N0M0 RCC. The quality of evidence is generally low and the results potentially biased. Further research in adequately powered trials is needed to answer these questions. 相似文献35.
Crispin Schneider Paul M. Bevis Paul Durdey Michael G. Thomas Paul A. Sylvester Robert J. Longman 《The surgeon》2013,11(3):141-146
AimThe colorectal two-week wait fast track (FT) referral system was nationally implemented in the UK in 2000 to ensure patients with colorectal cancer (CRC) received prompt access to specialized services. The aim of this study was to determine the association between the mechanism of referral to colorectal services and the 5-year outcomes for patients with CRC.MethodsConsecutive patients with newly diagnosed CRC presenting between October 2002 and September 2004 were identified retrospectively. Analysis for survival and recurrence of disease at 5 years from presentation was undertaken. Outcomes for patients were compared between fast track (FT), non-fast track (NFT) and emergency referral (ER) routes, using Kaplan–Meier survival estimates.ResultsOut of 189 patients, 96 (51%) presented via the FT, 41 (22.5%) via the NFT and 52 (27.5%) via the ER referral route. The 5-year overall survival was 52.6% ± 5.1, 41.5% ± 7.7 and 38.5% ± 6.7 for the FT-, NFT- and ER groups respectively (p = 0.075). The 5-year cancer specific survival was 60.3% ± 5.2, 58.8% ± 5.3 and 43.5% ± 7.2 for the FT-, NFT- and ER groups respectively (p = 0.056). Patients referred as emergencies had worse 5-year overall survival; 49.3% ± 4.3 (FT&NFT) vs. 38.5% ± 6.7 (ER) (p = 0.042) and 5-year cancer specific survival 59.8% ± 4.4 (FT&NFT) vs. 43.5% ± 7.2 (ER) (p = 0.016). A total of 136 patients (FT n = 71, NFT n = 34, ER n = 31) underwent potentially curative surgery. Differences in 5-year survival did not reach statistical significance in these patients.ConclusionReferral route to specialist services for patients with CRC via the fast track pathway compared to non-fast track pathway was not associated with improved survival. 相似文献
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Jorg R. Oddens Richard J. Sylvester Maurizio A. Brausi Wim J. Kirkels Cees van de Beek George van Andel Theo M. de Reijke Stephen Prescott J. Alfred Witjes Willem Oosterlinck 《European urology》2014
Background
Although maintenance bacillus Calmette-Guérin (BCG) is the recommended treatment in high-risk non–muscle-invasive bladder cancer (NMIBC), its efficacy in older patients is controversial.Objective
To determine the effect of age on prognosis and treatment outcome in patients with stage Ta T1 NMIBC treated with maintenance BCG.Design, setting, and participants
A total of 957 patients with intermediate- or high-risk Ta T1 (without carcinoma in situ) NMIBC were randomized in European Organization for Research and Treatment of Cancer (EORTC) trial 30911 comparing six weekly instillations of epirubicin, BCG, and BCG plus isoniazid followed by three weekly maintenance instillations over 3 yr.Outcome measurements and statistical analysis
Cox multivariate proportional hazards regression models were used to assess the relative importance of age for recurrence, progression, overall survival, and NMIBC-specific survival with adjustment for EORTC risk scores.Results and limitations
Overall, 822 eligible patients were included: 546 patients in the BCG with or without INH arms and 276 in the epirubicin arm. In patients treated with BCG with or without INH, 34.1% were >70 yr of age and 3.7% were >80 yr. With a median follow-up of 9.2 yr, patients >70 yr had a shorter time to progression (p = 0.028), overall survival (p < 0.001), and NMIBC-specific survival (p = 0.049) after adjustment for EORTC risk scores in the multivariate analysis. The time to recurrence was similar compared with the younger patients. BCG was more effective than epirubicin for all four end points considered, and there was no evidence that BCG was any less effective compared with epirubicin in patients >70 yr.Conclusions
In intermediate- and high-risk Ta T1 urothelial bladder cancer patients treated with BCG, patients >70 yr of age have a worse long-term prognosis; however, BCG is more effective than epirubicin independent of patient age.Patient summary
Intravesical bacillus Calmette-Guérin for non–muscle-invasive bladder cancer is less effective in patients >70 yr of age, but it is still more effective than epirubicin.Trial registration
This study was registered with the US National Cancer Institute clinical trials database (protocol ID: EORTC 30911; http://www.cancer.gov/clinicaltrials/search/view?cdrid=77075&version=HealthProfessional&protocolsearchid=12442243#StudyIdInfo_CDR0000077075). 相似文献40.
The high- and low-affinity receptor binding sites of growth hormone are allosterically coupled 下载免费PDF全文
Walsh ST Sylvester JE Kossiakoff AA 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(49):17078-17083
Growth hormone regulates its biological properties via a sequential hormone-induced receptor homodimerization mechanism. Using a mutagenesis-scanning analysis of 81 single and 32 pairwise double mutations, we show that the hormone's two spatially distal receptor binding sites (Site1 and Site2) are allosterically coupled. These allosteric effects are focused among a relatively few residues centered around the interaction between Asp-116 of the hormone and Trp-169 of the receptor in Site2. A rearrangement of this interaction triggered by mutations in Site1 produces both a major conformation and energetic reorganization of Site2, surprisingly without a reduction in overall binding affinity. Additionally, the data suggest a change in the conformational dynamics of several groups in Site2 that appear to be important in defining the Site2 interaction. Changes in binding energy of the affected Site2 residues usually range in magnitude from 3- to 60-fold, but in one case are as large as 10(4). 相似文献