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Broglio KR, Connor JT, Meurer WJ, Durkalski VL, Johnston KC. Abstract TP236: The Stroke Hyperglycemia Insulin Network Effort (SHINE) Trial: A Case Study of a Bayesian Trial Design. Stroke 2013. [DOI: 10.1161/str.44.suppl_1.atp236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction:
The “Adaptive Designs Accelerating Promising Trials into Treatments (ADAPT-IT)” project is a collaborative effort supported by the NIH and FDA to explore how adaptive clinical trial design might improve the evaluation of drugs and medical devices. We use the NINDS-supported Neurological Emergencies Treatment Trials network as a "laboratory" in which to study the development of adaptive clinical trial designs. The Stroke Hyperglycemia Insulin Network Effort (SHINE) trial was fully funded by the NIH-NINDS at the start of ADAPT-IT and is a currently ongoing phase III trial of tight glucose control in hyperglycemic acute ischemic stroke patients. Within ADAPT-IT, a Bayesian alternative design was developed. The primary endpoint is a severity-adjusted dichotomized 90-day modified Rankin scale (mRS).
Objective:
To present both designs and compare their operating characteristics.
Methods:
10000 trials are simulated under treatment effects ranging from 0% to 7%. We present the mean sample size and probabilities of trial success or futility.
Results:
The SHINE trial design includes a group sequential procedure with 4 interim analyses to monitor for early efficacy and futility. A maximum of 1400 patients provide 80% power to detect a 7% absolute difference between treatment arms with an overall Type I error rate of 5%. The expected sample size is 1050 patients. This design also incorporates sample size re-estimation and response adaptive randomization. The Bayesian alternative would enroll a maximum of 1400 patients, equally randomized, but employs more frequent interim looks based on predictive probabilities and incorporates a longitudinal model of the primary endpoint. This design has similar power and Type I error and would enroll a mean of 733 and 979 patients under the null and alternative hypotheses respectively.
Conclusions:
Simulations suggest that the designs have similar power and Type I error. The Bayesian alternative, with more frequent looks, has a greater chance of stopping early for overwhelming efficacy or futility. The Bayesian alternative will be retrospectively executed upon completion of SHINE to later compare the designs based on their use of patient resources, time, and strength of conclusions in a real world setting.
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Connor JT, Lewis RJ, Berry DA, Berry SM. FDA recalls not as alarming as they seem. ARCHIVES OF INTERNAL MEDICINE 2011; 171:1044-1046. [PMID: 21670380 DOI: 10.1001/archinternmed.2011.242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
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Lewis RJ, Connor JT, Teerlink JR, Murphy JR, Cooper LT, Hiatt WR, Brass EP. Application of adaptive design and decision making to a phase II trial of a phosphodiesterase inhibitor for the treatment of intermittent claudication. Trials 2011; 12:134. [PMID: 21612611 PMCID: PMC3126735 DOI: 10.1186/1745-6215-12-134] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 05/25/2011] [Indexed: 12/02/2022] Open
Abstract
Background Claudication secondary to peripheral artery disease (PAD) is associated with substantial functional impairment. Phosphodiesterase (PDE) inhibitors have been shown to increase walking performance in these patients. K-134 is a selective PDE 3 inhibitor being developed as a potential treatment for claudication. The use of K-134, as with other PDE 3 inhibitors, in patients with PAD raises important safety and tolerability concerns, including the induction of cardiac ischemia, tachycardia, and hypotension. We describe the design, oversight, and implementation of an adaptive, phase II, dose-finding trial evaluating K-134 for the treatment of stable, intermittent claudication. Methods The study design was a double-blind, multi-dose (25 mg, 50 mg, and 100 mg of K-134), randomized trial with both placebo and active comparator arms conducted in the United States and Russia. The primary objective of the study was to compare the highest tolerable dose of K-134 versus placebo using peak walking time after 26 weeks of therapy as the primary outcome. Study visits with intensive safety assessments were included early in the study period to provide data for adaptive decision making. The trial used an adaptive, dose-finding strategy to efficiently identify the highest dose(s) most likely to be safe and well tolerated, based on the side effect profiles observed within the trial, so that less promising doses could be abandoned. Protocol specified criteria for safety and tolerability endpoints were used and modeled prior to the adaptive decision making. The maximum target sample size was 85 subjects in each of the retained treatment arms. Results When 199 subjects had been randomized and 28-day data were available from 143, the Data Monitoring Committee (DMC) recommended termination of the lowest dose (25 mg) treatment arm. Safety evaluations performed during 14- and 28-day visits which included in-clinic dosing and assessments at peak drug concentrations provided core data for the DMC review. At the time of review, no subject in any of the five treatment arms (placebo, three K-134-containing arms, and cilostazol) had met pre-specified definitions for resting tachycardia or ischemic changes on exercise ECG. If, instead of dropping the 25-mg K-134 treatment arm, all arms had been continued to full enrollment, then approximately 43 additional research subjects would have been required to complete the trial. Conclusions In this phase II, dose-finding trial of K-134 in the treatment of stable intermittent claudication, no concerning safety signals were seen at interim analysis, allowing the discontinuation of the lowest-dose-containing arm and the retention of the two highest-dose-containing arms. The adaptive design facilitated safe and efficient evaluation of K-134 in this high-risk cardiovascular population. Trial registration ClinicalTrials.gov: NCT00783081
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Shermock KM, Connor JT, Lavallee DC, Streiff MB. Assessment of agreement between INR measures must correspond to a clinical reality. Clin Chim Acta 2010; 411:1384-5; author reply 1386-7. [DOI: 10.1016/j.cca.2010.05.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Revised: 03/22/2010] [Accepted: 05/10/2010] [Indexed: 10/19/2022]
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Luce BR, Kramer JM, Goodman SN, Connor JT, Tunis S, Whicher D, Schwartz JS. Rethinking randomized clinical trials for comparative effectiveness research: the need for transformational change. Ann Intern Med 2009; 151:206-9. [PMID: 19567619 DOI: 10.7326/0003-4819-151-3-200908040-00126] [Citation(s) in RCA: 257] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Shermock KM, Connor JT, Lavallee DC, Streiff MB. Clinical decision-making as the basis for assessing agreement between measures of the International Normalized Ratio. J Thromb Haemost 2009; 7:87-93. [PMID: 19017256 DOI: 10.1111/j.1538-7836.2008.03225.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND The now classic approach of Bland and Altman is often used to assess the level of agreement between International Normalized Ratio (INR) measures. However, we are concerned that this method does not define agreement in a clinically meaningful way. Agreement between measures should be characterized explicitly in terms of clinical decisions that result from INR measures. OBJECTIVES To develop and validate an extension of the Bland-Altman method to assess agreement between INR measures, based explicitly on the way clinicians make decisions. METHODS AND RESULTS We developed a clinically based graphical method to estimate the level of agreement between measures of INR. We identified clinically relevant INR ranges using epidemiologic and clinical evidence regarding risk and expected outcome at different INR ranges. Clinical decisions were expected to agree within these INR ranges and, therefore, the ranges became the basis for establishing agreement between measures. We used paired INR measures and resultant clinical decisions measured during a previous prospective study to validate and compare the accuracy of our model to those of Bland and Altman's and other published models. Our method more accurately predicts when warfarin dosing decisions differ than the Bland-Altman method (P < 0.02). Our method is also superior to other published methods, particularly at the important task of identifying when measures lead to discrepant clinical decisions. CONCLUSIONS We introduced and validated an improvement of the Bland-Altman method to assess agreement between INR measures. Our model is superior because it is based explicitly on factors that influence clinical decision-making.
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Abstract
Scientific and medical authors tend to be biased toward submitting "statistically significant" findings for publication. Journals show a similar bias in publishing such "positive" studies. The large number of publications in medical research means that, in a field obsessed with controlling Type I error rates, we have journals with an abundance of Type I errors. Failing to publish studies that do not show a treatment or exposure effect creates a literature conspicuously absent of trials necessary for unbiased meta-analyses and systematic reviews. Furthermore, by shelving or rejecting studies with nonstatistically significant outcomes, authors and editors censor the most important contributors to medical research: our consenting volunteers.
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Lucey MR, Connor JT, Boyer TD, Henderson JM, Rikkers LF. Alcohol consumption by cirrhotic subjects: patterns of use and effects on liver function. Am J Gastroenterol 2008; 103:1698-706. [PMID: 18494835 DOI: 10.1111/j.1572-0241.2008.01837.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE We investigated patterns of use of alcohol and its clinical effects among cirrhotic subjects who participated in a randomized clinical trial comparing the efficacy of transjugular intravenous portosystemic shunt and distal splenorenal shunt. METHODS There were 132 cirrhotic subjects, 78 with alcoholic liver disease (ALD), who were followed for a median of 49 months (range 2-93 months). Alcohol use was assessed by patient questionnaire, with corroboration by family members. RESULTS Twenty-eight subjects (21%) were drinking at study entry and 60 subjects (45%) drank during follow-up. Heavy drinking (>4 drinks/day) was recorded in 25 ALD subjects, but in no non-ALD subjects (P < 0.0001). Drinking by ALD subjects was associated with a 153% increase in gamma-glutamyl transpeptidase (GGT) (P < 0.0001). The frequencies of death (46%vs 30%), ascites (33%vs 20%), encephalopathy (56%vs 42%), and variceal bleeding (11%vs 3%) were greater in the ALD group. In a Cox proportional hazards model only "ever heavy drinking" was associated with death (P= 0.0099), while recent heavy drinking increased the hazard of variceal hemorrhage dramatically (odds ratio 10.85). CONCLUSIONS Whereas most cirrhotic subjects, alcoholic or not, did not drink during 5 yr of observation, heavy alcohol use occurred exclusively in ALD patients. Alcohol use by ALD subjects was associated with elevations in GGT and was linked to death and with rebleeding from shunt dysfunction.
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Abstract
Clinical studies are used to make generalizations about a population of interest. Bias can be defined as the systematic error in study design or implementation, leading to inaccurate generalizations about this population. There is a potential for bias in all of the clinical studies on sodium phosphate colonoscopy preparation, and this bias may lead to the differing conclusions regarding safety drawn by the authors. A review of some of the relevant literature is presented, as well as a discussion of propensity score analysis, a technique used to help clarify the causal pathway in nonrandomized studies. Based on the available information, it is reasonable to follow the recommendations contained in the consensus document of the American Society of Colon and Rectal Surgeons, American Society for Gastrointestinal Endoscopy, and Society of American Gastrointestinal and Endoscopic Surgeons regarding sodium phosphate colonoscopy preparation.
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Hustey FM, Mion LC, Connor JT, Emerman CL, Campbell J, Palmer RM. A Brief Risk Stratification Tool to Predict Functional Decline in Older Adults Discharged from Emergency Departments. J Am Geriatr Soc 2007; 55:1269-74. [PMID: 17661968 DOI: 10.1111/j.1532-5415.2007.01272.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVES To determine the effectiveness of the six-item Triage Risk Screening Tool (TRST) to assess baseline functional status and predict subsequent functional decline in older community-dwelling adults discharged home from the emergency department (ED). DESIGN Secondary data analysis of a randomized, controlled trial. SETTING EDs of two urban academic hospitals. PARTICIPANTS Six hundred fifty community-dwelling adults aged 65 and older presenting to the ED and discharged home. Patients were categorized a priori as "high risk" if they had cognitive impairment or two or more risk factors on the TRST. MEASUREMENTS Functional status: summed activity of daily living (ADL) and instrumental activity of daily living (IADL) scores at baseline, 30 days, and 120 days. Self-perceived physical health: standardized physical health component of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Functional decline: loss of one or more ADLs and one or more IADLs from ED baseline at 30 and 120 days. Decline in self-perceived physical health: follow-up SF-36 standardized physical health component scores four or more points lower than baseline. RESULTS TRST scores correlated with baseline ADL impairments, IADL impairments, and self-perceived physical health at all endpoints (P<.001). A TRST score of two or more was moderately predictive of decline in ADLs or IADLs (30-day ADL area under the receiver operating characteristic curve (AUC)=0.64; 95% confidence interval (CI)=0.56-0.72; 120-day ADL AUC=0.66; 95% CI=0.58-0.74) but not perceived physical health. CONCLUSION The TRST identifies baseline functional impairment in older ED patients and is moderately predictive of subsequent functional decline after an initial ED visit. The TRST provides a valid proxy measure for assessing functional status in the ED and may be useful in identifying high-risk patients who would benefit from referrals for further evaluation or surveillance upon ED discharge.
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Falk GW, Thota PN, Richter JE, Connor JT, Wachsberger DM. Barrett's esophagus in women: demographic features and progression to high-grade dysplasia and cancer. Clin Gastroenterol Hepatol 2005; 3:1089-94. [PMID: 16271339 DOI: 10.1016/s1542-3565(05)00606-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Barrett's esophagus is traditionally considered a disease of older white men. The aims of this study were to compare the demographic features of Barrett's esophagus in men and women and to determine the prevalence and incidence of high-grade dysplasia and cancer in these patients. METHODS All patients enrolled in the Cleveland Clinic Barrett's Esophagus Registry from 1979-2002 were studied. Age, ethnicity, number of endoscopies, hiatal hernia size, length of Barrett's segment, and prevalence and incidence of high-grade dysplasia and cancer were compared between men and women. RESULTS There were 839 patients in the registry (628 men and 211 women). Barrett's segment length was greater in men than in women (mean, 5.06 +/- 4.2 vs 4.05 +/- 3.27 cm, respectively; P = .003). There were no significant differences for other parameters. There were 114 prevalence cases of high-grade dysplasia or cancer (96 men, 18 women). Women were less likely to have prevalent high-grade dysplasia or cancer than men (odds ratio, 0.52; 95% confidence interval, 0.31-0.88; P = .015). There were 13 incidence cases of high-grade dysplasia or cancer (11 men, 2 women) during a mean follow-up of 4.72 years, which was similar in both genders with an incidence rate of 1 in 179 patient-years of follow-up for women and 1 in 91 patient-years of follow-up in men. CONCLUSIONS Twenty-five percent of patients in our registry are women. The length of Barrett's esophagus is greater in men than in women, but other features are similar. The prevalence of high-grade dysplasia/cancer in women is approximately half that of men. Incidence rates for high-grade dysplasia/cancer are similar in men and women, although the number of cases is small.
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Gorgun E, Remzi FH, Montague DK, Connor JT, O'Brien K, Loparo B, Fazio VW. Male sexual function improves after ileal pouch anal anastomosis. Colorectal Dis 2005; 7:545-50. [PMID: 16232233 DOI: 10.1111/j.1463-1318.2005.00895.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE Restorative Proctocolectomy and Ileal Pouch Anal Anastomosis has become the gold standard surgical therapy for the majority of patients with mucosal ulcerative colitis. However sexual functional disturbances after this procedure can be a concern for patients. Therefore the aim of this study was to determine the outcome of sexual-function related quality of life in male patients undergoing restorative proctocolectomy. METHODS One hundred and twenty-two male patients who underwent restorative proctocolectomy with ileal pouch anal anastomosis between 1995 and 2000 were evaluated by the validated International Index of Erectile Function (IIEF) scoring instrument. This index scale examines sexual function in five categories. These are erectile function, orgasmic function, sexual desire, intercourse satisfaction and overall satisfaction. The IIEF instrument was administered after surgery and then scores before and after RP/IPAA were evaluated and compared. The significance of age at the time of the surgery, type of surgery, type of anastomotic technique (mucosectomy vs stapled) and septic complications on sexual functional outcome were also investigated. RESULTS Mean age at the time of the surgery was 39.9 +/- 11.5 years. The mean follow-up period (time between pouch surgery and IIEF completed) was 3.6 +/- 1.8 years. There was statistically significant improvement in 4 of 5 categories of sexual function (erectile function, sexual desire, intercourse satisfaction, and overall satisfaction) where patients had improved scores after surgery compared to prior to surgery. The mean erectile function score increased pre to post surgery by 2.12 points (P = 0.02), which indicates better sexual results. Anastomotic technique and septic complication did not influence the results, however, older age had a negative impact on results. CONCLUSIONS Despite some adverse sexual functions, male patients who undergo RP/IPAA for the surgical management of their colitis may preserve or improve their overall sexual functional outcome.
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Shen B, Porter EM, Reynoso E, Shen C, Ghosh D, Connor JT, Drazba J, Rho HK, Gramlich TL, Li R, Ormsby AH, Sy MS, Ganz T, Bevins CL. Human defensin 5 expression in intestinal metaplasia of the upper gastrointestinal tract. J Clin Pathol 2005; 58:687-94. [PMID: 15976333 PMCID: PMC1770712 DOI: 10.1136/jcp.2004.022426] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Upper gastrointestinal tract intestinal metaplasia (IM) is termed Barrett's oesophagus (BO) or gastric intestinal metaplasia (GIM), depending on its location. BO and GIM are associated with chemical exposure resulting from gastro-oesophageal reflux and chronic Helicobacter pylori infection, respectively. Paneth cells (PCs), characterised by cytoplasmic eosinophilic granules, are found in a subset of IM at these sites, but histology may not accurately detect them. AIM To determine human defensin 5 (HD5; an antimicrobial peptide produced by PCs) expression in BO and GIM, and to investigate its association with H pylori infection. METHODS Endoscopic biopsies from 33 patients with BO and 51 with GIM, and control tissues, were examined by routine histology and for H pylori infection and HD5 mRNA and protein expression. RESULTS In normal tissues, HD5 expression was specific for PCs in the small intestine. Five patients with BE and 42 with GIM expressed HD5, but few HD5 expressing cells in IM had the characteristic histological features of PCs. Most HD5 positive specimens were H pylori infected and most HD5 negative specimens were not infected. CONCLUSIONS HD5 immunohistochemistry was often positive in IM when PCs were absent by conventional histology. Thus, HD5 immunohistochemistry may be superior to histology for identifying metaplastic PCs and distinguishing GIM from BO. The higher frequency of HD5 expression in GIM than in BO is associated with a higher frequency of H pylori infection, suggesting that in IM PCs may form part of the mucosal antibacterial response.
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Harrison AM, Davis S, Reid JR, Morrison SC, Arrigain S, Connor JT, Temple ME. Neonates with hypoplastic left heart syndrome have ultrasound evidence of abnormal superior mesenteric artery perfusion before and after modified Norwood procedure. Pediatr Crit Care Med 2005; 6:445-7. [PMID: 15982432 DOI: 10.1097/01.pcc.0000163674.53466.ca] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To a) describe superior mesenteric artery resistive index, as an estimate of perfusion, before and after modified Norwood; and b) assess incidence of diastolic flow reversal in the superior mesenteric artery before and after modified Norwood. DESIGN Prospective observational trial. SETTING Children's hospital pediatric intensive care unit. PATIENTS Ten newborns with hypoplastic left heart syndrome. INTERVENTIONS Ultrasound documentation of superior mesenteric artery diastolic flow direction and measurement of superior mesenteric artery resistive index 24-48 hrs before and 24-48 hrs after modified Norwood. MEASUREMENTS AND MAIN RESULTS Seven males and three females were enrolled. There was no change between the superior mesenteric artery resistive index pre- vs. postoperatively-0.99 (95% confidence interval, 0.85, 1.12) vs. 1.07 (95% confidence interval, 1.0, 1.15) (p = .13). Incidence of retrograde diastolic blood flow in the superior mesenteric artery was not different pre- vs. postoperatively (70% vs. 50%, p = .41). No patients developed necrotizing enterocolitis and all survived to hospital discharge. CONCLUSIONS Ultrasound measurements in neonates with hypoplastic left heart syndrome suggest that superior mesenteric artery perfusion, as measured by resistive index, is impaired. Superior mesenteric artery diastolic flow reversal is common before and immediately after modified Norwood.
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Takagaki M, McCarthy PM, Inoue M, Chung M, Connor JT, Dessoffy R, Ochiai Y, Howard M, Doi K, Kopcak M, Mazgalev TN, Fukamachi K. Myocardial compliance was not altered after acute induction of atrial fibrillation in sheep. Med Sci Monit 2005; 11:BR147-153. [PMID: 15917708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Accepted: 01/10/2005] [Indexed: 05/02/2023] Open
Abstract
BACKGROUND Although left ventricular (LV) contractility in atrial fibrillation (Af) is known to change in a beat-to-beat fashion, little is known about the changes in LV compliance in Af. MATERIAL/METHODS We experimentally induced tachycardic Af (average heart rate - 154 beats per minute) in 18 sheep. LV volume and pressure were simultaneously monitored using a conductance catheter. LV end-diastolic volume (V(ED)) and pressure (P(ED)) were plotted in a beat-to-beat fashion and fitted to the following exponential equation (P(ED)=gamma x e(b x V(ED))) in each animal. A random effects model was constructed to determine if the intercepts and slopes differ. RESULTS In all animals, those plots after the induction of Af fit quite well to the exponential function (r=0.834+/-0.184) by gating short preceding interval (RR1) beats. By simply taking the natural logarithm of both sides in the equation, the linear relationship (ln(P(ED)) =alpha+ betaxV(ED), where a = lng) was observed in all animals before (normal sinus rhythm, NSR) and after the induction of Af. Only two of 18 intercepts and four of 18 slopes deviate between NSR and Af. Most interestingly, the random effects model clearly detailed that the average animal had intercepts and slopes that were not discernibly different between NSR and Af. CONCLUSIONS Unlike LV contractility, myocardial compliance did not change after the acute induction of Af. These interesting results may give us insights into the understanding of the physiology in acute rapid Af.
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Jeng BH, Shadrach KG, Meisler DM, Hollyfield JG, Connor JT, Koeck T, Aulak KS, Stuehr DJ. Immunohistochemical detection and Western blot analysis of nitrated protein in stored human corneal epithelium. Exp Eye Res 2005; 80:509-14. [PMID: 15781278 DOI: 10.1016/j.exer.2004.10.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2004] [Accepted: 10/28/2004] [Indexed: 10/26/2022]
Abstract
While the production of nitric oxide by human corneas in storage has recently been demonstrated, protein nitration as a result of this production has not been demonstrated. In this study, nitrated protein accumulation in the epithelium of stored human corneas was assessed. One half of five donor corneas maintained in storage media for 3 days were prepared for immunohistochemical studies. The other halves remained in storage media for 7 additional days and were also processed for immunohistochemistry. Mouse monoclonal antibody to nitrotyrosine adducts was used to define the localisation of these epitopes. The density of antibody staining was observed and quantified on a digital camera system and statistically analysed. Immunostaining in the epithelium was greater in tissues recovered after 10 days in storage compared to the intensity of staining after 3 days of storage (p<0.0001). No staining was evident in the epithelium in sections exposed to non-immune mouse IgG. Western blot analysis was performed on epithelial cells scraped from corneal surfaces of one-half of four donor corneas in storage for 3 days and from the other half at 10 days of storage. Nitrated BSA was used as a positive control. After extraction and homogenisation, identical protein concentrations of each sample were loaded per lane on 10% gels and subjected to SDS-PAGE. Proteins were blotted and probed with the anti-nitrotyrosine antibody. Western blot immunoreactivity was detected in epithelial samples at the 3 and 10 day recovery times with the latter samples showing greater staining intensity. Nitrated protein, thought to indicate toxic peroxynitrite formation, accumulates in the human corneal epithelium with time of storage. Our study shows that there is an association between increased nitrated protein and storage time.
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Zutshi M, Delaney CP, Senagore AJ, Mekhail N, Lewis B, Connor JT, Fazio VW. Randomized controlled trial comparing the controlled rehabilitation with early ambulation and diet pathway versus the controlled rehabilitation with early ambulation and diet with preemptive epidural anesthesia/analgesia after laparotomy and intestinal resection. Am J Surg 2005; 189:268-72. [PMID: 15792748 DOI: 10.1016/j.amjsurg.2004.11.012] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Revised: 11/19/2004] [Accepted: 11/19/2004] [Indexed: 11/20/2022]
Abstract
BACKGROUND Multimodal postoperative care regimens accelerate recovery after abdominal surgery. The benefit of thoracic epidural (TE) analgesia over patient-controlled analgesia (PCA) remains unproven when used with a fast-track postoperative care plan. METHODS Fifty-six patients undergoing major intestinal resection, and on a fast-track postoperative care plan, were randomized to preemptive TE or PCA. Patients were evaluated at standard time points for pain score, quality of life (Short Form-36), and complications. Oral analgesia was substituted for TE and PCA on the second postoperative day. Discharge criteria were identical for both groups. RESULTS Six patients (20.6%) had a failed epidural. There was no difference in length of stay (5.8 versus 6.2 days, TE versus PCA, P = .55), total length of stay (including readmissions), pain scores, quality of life, complications, or hospital costs at any time point. CONCLUSION TE offers no advantage over PCA for patients undergoing major intestinal resections who are on a fast-track postoperative care plan using PCA.
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Harrison AM, Yaldoo DT, Fiesler CM, Connor JT. Pre-to-post race changes in self-reported depression scores in ultra-distance triathletes - a pilot study. SOUTH AFRICAN JOURNAL OF SPORTS MEDICINE 2004. [DOI: 10.17159/2413-3108/2003/v15i3a222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
SA Sports Medicine Vol.15(3) 2003: 11-16
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Shen B, Zuccaro G, Gramlich TL, Gladkova N, Trolli P, Kareta M, Delaney CP, Connor JT, Lashner BA, Bevins CL, Feldchtein F, Remzi FH, Bambrick ML, Fazio VW. In vivo colonoscopic optical coherence tomography for transmural inflammation in inflammatory bowel disease. Clin Gastroenterol Hepatol 2004; 2:1080-7. [PMID: 15625653 DOI: 10.1016/s1542-3565(04)00621-4] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Transmural inflammation, a distinguishing feature of Crohn's disease (CD), cannot be assessed by conventional colonoscopy with mucosal biopsy. Our previous ex vivo study of histology-correlated optical coherence tomography (OCT) imaging on colectomy specimens of CD and ulcerative colitis (UC) showed that disruption of the layered structure of colon wall on OCT is an accurate marker for transmural inflammation of CD. We performed an in vivo colonoscopic OCT in patients with a clinical diagnosis of CD or UC using the previously established, histology-correlated OCT imaging criterion. METHODS OCT was performed in 40 patients with CD (309 images) and 30 patients with UC (292 images). Corresponding endoscopic features of mucosal inflammation were documented. Two gastroenterologists blinded to endoscopic and clinical data scored the OCT images independently to assess the feature of disrupted layered structure. RESULTS Thirty-six CD patients (90.0%) had disrupted layered structure, whereas 5 UC patients (16.7%) had disrupted layered structure (P < .001). Using the clinical diagnosis of CD or UC as the gold standard, the disrupted layered structure on OCT indicative of transmural inflammation had a diagnostic sensitivity and specificity of 90.0% (95% CI: 78.0%, 96.5%) and 83.3% (95% CI: 67.3%, 93.3%) for CD, respectively. The kappa coefficient in the interpretation of OCT images was 0.80 (95% CI: 0.75, 0.86, P < .001). CONCLUSIONS In vivo colonoscopic OCT is feasible and accurate to detect disrupted layered structure of the colon wall indicative of transmural inflammation, providing a valuable tool to distinguish CD from UC.
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Lynch AC, Delaney CP, Senagore AJ, Connor JT, Remzi FH, Fazio VW. Clinical outcome and factors predictive of recurrence after enterocutaneous fistula surgery. Ann Surg 2004; 240:825-31. [PMID: 15492564 PMCID: PMC1356488 DOI: 10.1097/01.sla.0000143895.17811.e3] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Recent experience with surgery for enterocutaneous fistulae (ECF) at a specialist colorectal unit is reviewed to define factors relating to a successful surgical outcome. SUMMARY BACKGROUND DATA ECF cause significant morbidity and mortality and need experienced surgical management. Previous publications have concentrated on mortality resulting from fistulae, while factors affecting recurrence have not previously been a focus of analysis. METHODS Records were reviewed of patients who had ECF surgery (1994-2001). Management strategy involved early drainage of sepsis and nutritional support prior to elective ECF repair, with selective defunctioning proximal stoma formation. RESULTS A total of 205 patients were available (89 males, 43%; median age, 51 years; range, 16-86) years). ECF were related to Crohn's disease in 95, ulcerative colitis in 18, diverticular disease in 17, carcinoma in 25 (16 after radiotherapy), mesh ventral hernia repair in 21, and other causes in 29. Forty-one (20%) had undergone attempted fistula repair at other institutions. Initial management included CT-guided drainage of an intra-abdominal abscess in 23 patients, and total parenteral nutrition in 74 (36%). A total of 203 patients had definitive ECF repair. Forty-four had oversewing or wedge resection of the fistula, and 159 had resection and reanastomosis of the involved small bowel segment or ileocolic anastomosis. Ninety-day operative mortality was 3.5%. A total of 42 (20.5%) patients developed ECF recurrence within 3 months. Multivariate analysis demonstrated that recurrence was more likely after oversewing (36%) than resection (16%, P = 0.006). CONCLUSIONS A strategy of drainage of acute sepsis, maintenance of nutritional support prior to surgery, and selective use of PS allows for primary closure in 80% of complicated ECF. Resection should be performed when feasible.
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Guardino JM, Vela MF, Connor JT, Richter JE. Pneumatic dilation for the treatment of achalasia in untreated patients and patients with failed Heller myotomy. J Clin Gastroenterol 2004; 38:855-60. [PMID: 15492600 DOI: 10.1097/00004836-200411000-00004] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
BACKGROUND Laparoscopic Heller myotomy (HM) has become an increasingly preferred modality to treat achalasia. However, the treatment course after a failed myotomy is controversial with fears that pneumatic dilation (PD) has high perforation risk. GOAL To compare success and safety of graded PD with Rigiflex balloons in achalasia patients without a prior HM (untreated cases) and those with a failed HM. STUDY A total of 108 patients were retrospectively evaluated: 96 untreated cases (53 male, 43 female, mean age 51 years) and 12 failed HM(7 male, 5 female, mean age 54 years). Symptoms (dysphagia and regurgitation) and physiologic studies, lower esophageal sphincter pressure (LESP) and timed barium swallow, assessed pre- and post-PD. Success was defined as: 1) symptom improvement to </=2 to 4 times per week, and 2) >/=80% decrease in 5-minute barium column height from initial timed barium swallow. RESULTS A total of 139 PDs performed (117 untreated cases, 22 failed HM): 2 perforations in untreated cases and none in failed HM group. Baseline demographics were similar, but failed HM patients had significantly lower LESP and timed barium swallow columns. Despite less LES resistance, failed HM group (symptom and physiologic success: 50% and 10%) did not do as well after PD as compared with untreated cases (symptom and physiologic success: 74% and 52%, respectively). Five failed HM patients had good symptom relief after PD compared with poor responders these patients were older (>50 years) and had LESP >17 mm Hg. CONCLUSIONS PD perforation risk is not higher after HM. Despite lower LES pressure, patients undergoing PD after failed HM do not do as well as untreated cases. Factors predicting better outcome include older age and higher LES pressure.
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Abstract
As is common in current biomedical research, about 85% of original contributions in The American Journal of Gastroenterology in 2004 have reported p-values. However, none are reported in this issue's article by Abraham et al. who, instead, rely exclusively on effect size estimates and associated confidence intervals to summarize their findings. Authors using confidence intervals communicate much more information in a clear and efficient manner than those using p-values. This strategy also prevents readers from drawing erroneous conclusions caused by common misunderstandings about p-values. I outline how standard, two-sided confidence intervals can be used to measure whether two treatments differ or test whether they are clinically equivalent.
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Abstract
OBJECTIVE Laparotomy is the treatment of choice in Peutz-Jeghers Syndrome (PJS) patients for endoscopically irretrievable symptomatic polyps and polyp-related complications. During the last decade, we have operated on majority of the PJS patients with the purpose of removing all the gastrointestinal polyps (clean sweep), when an operation was indicated. The aim of this study is to evaluate the effect of clean sweep technique on the need for repeated surgery compared to a problem focused approach. PATIENTS AND METHODS All patients with PJS treated in our institution since 1964 were studied. They were placed into two groups; those who had a problem-focused operation and those who were operated with the purpose of removing all small and large intestinal polyps. Demographics, presentation, follow-up period and the need for recurrent surgery were compared. RESULTS We identified 11 patients (4 males, 7 females). Eight patients (5 females; median age 18.5) had problem-focused surgery for bleeding-anaemia (n = 3) or obstruction-intussusception (n = 5). These patients required 23 further operations within 87 patient-follow-up-years (2.64 operations per 10 years). Three patients (2 females; median age 6) were operated for bleeding-anaemia (n = 1) or obstruction-intussusception (n = 2) using the 'clean sweep' approach. These patients did not require any further surgery within 21 patient-follow-up-years. The gender, presentation and follow-up periods were similar between the groups. However, the 'clean sweep' technique appears to have reduced the need for further operations when it is compared with problem-focused approach (P = 0.01). CONCLUSION To reduce the need for abdominal surgery and consequent problems in PJS patients, an attempt to remove all detected polyps (clean sweep technique) may be beneficial in these patients.
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