Jeremy Theal | University of Toronto (original) (raw)

Papers by Jeremy Theal

Sa1504 “Shaken, Not Stirred.” Towards Standardized Synoptic Reporting in GI Endoscopy Electronic Medical Records (EMRs)

Gastrointestinal Endoscopy, 2015

Hepatitis B Virus Replication in Damaged Endothelial Tissues of Patients with Extrahepatic Disease

The American Journal of Gastroenterology, 2005

Hepatitis B virus (HBV) infection may be complicated by extrahepatic manifestations such as polya... more Hepatitis B virus (HBV) infection may be complicated by extrahepatic manifestations such as polyarteritis nodosa (PAN), glomerulonephritis, polymyositis, and dermatitis, but the etiology of these processes is not yet clear. HBV replication has been demonstrated in a variety of extrahepatic tissues and cell types, but the possible pathogenetic role of extrahepatic HBV replication has not been fully explored in patients with extrahepatic manifestations of HBV infection. In this case series, immunohistochemistry and in situ hybridization studies were performed on extrahepatic tissues from one HBsAg-positive patient with PAN and another HBsAg-positive patient with polymyositis, using HBsAg-seronegative control subjects with the same vasculitic disorders as controls. Tissue samples from the two study patients had detectable HBV RNA, replicative intermediates of HBV DNA, as well as HBsAg and HBcAg localized to vascular endothelium. In contrast, HBsAg-negative control patients had no tissue reactivity. Our results suggest that patients with HBV-related extrahepatic disease have evidence of viral replication in damaged extrahepatic endothelial tissues. While further studies would be required to support a hypothesis of causality, these findings suggest a role for both immune complex deposition and viral replication within diseased endothelial tissue in the pathogenesis of these poorly understood extrahepatic disorders.

A randomized, controlled crossover trial of ondansetron in patients with primary biliary cirrhosis and fatigue

Hepatology, 2005

Fatigue is common in primary biliary cirrhosis (PBC). Altered central serotonergic neurotransmiss... more Fatigue is common in primary biliary cirrhosis (PBC). Altered central serotonergic neurotransmission may be involved in its pathogenesis. This multicenter, randomized, double-blind, placebo-controlled, crossover trial evaluated the efficacy of ondansetron, a selective 5-HT3 receptor subtype antagonist, for treating fatigue in PBC. A crossover design was chosen, allowing subjects to serve as their own controls-appropriate to evaluate fatigue, a subjective symptom. Sixty patients with clinically stable PBC, a Fatigue Severity Score (FSS) > 4, and no other identifiable cause for fatigue were enrolled. Subjects were randomized to receive ondansetron (4 mg) or placebo orally 3 times daily for 4 weeks (period 1). Subjects then crossed over, after a minimum 1-week washout period, for a further 4 weeks of ondansetron or placebo (period 2). Fatigue was measured at the beginning and end of each period by using the FSS and Fatigue Impact Scale (FIS). Six patients withdrew; the remaining 54 subjects had a mean baseline FSS of 5.55 (+/-0.1). Response to study medication in period 1 versus period 2 was not uniform; thus, it was necessary to analyze the trial periods separately. In period 1, there was no significant additional fatigue reduction on ondansetron over placebo. During period 2, FSS and FIS decreased significantly on ondansetron versus placebo (P = .001). However, period 2 results were invalidated because drug side effects unblinded subjects (constipation affected 63.0% of patients taking ondansetron, versus 13.3% on placebo). In conclusion, ondansetron administration did not confer clinically significant fatigue reduction when compared with placebo in our study population.

Gastrointestinal Endoscopy, 2004

Background: The aim of this study was to determine whether digital video is suitable for the docu... more Background: The aim of this study was to determine whether digital video is suitable for the documentation of colonoscopy. Standards are required for the visual documentation of endoscopic findings and to optimize image quality while limiting file size and bandwidth requirements. Methods: Video recordings of colonoscopy procedures were encoded using a common video compression method at selected data rates and resolutions. Twelve reviewers were selected, each of whom was assigned 8 video review sessions, each consisting of 5 colonoscopy procedures. The reviewers rated the following: level of confidence that the cecum was demonstrated, subjective quality of the video compared with actual videocolonoscopy, and whether the video was of ''diagnostic quality.'' Results: Reviewers were confident that the cecum was demonstrated in all cases except at the lowest data rate. The 1.0 Mbps standard interchange format video provided an optimal balance between quality and file size. Conclusions: For the documentation of colonoscopy, 1.0 Mbps is acceptable and results in a file size of 7.5 Mbytes/min, which is manageable for most modern hospital and telehealth networks.

CPOE with evidence-based clinical decision support improves patient outcomes: the journey to date for a Canadian hospital

Healthcare quarterly (Toronto, Ont.), 2014

Sa1504 “Shaken, Not Stirred.” Towards Standardized Synoptic Reporting in GI Endoscopy Electronic Medical Records (EMRs)

Gastrointestinal Endoscopy, 2015

Hepatitis B Virus Replication in Damaged Endothelial Tissues of Patients with Extrahepatic Disease

The American Journal of Gastroenterology, 2005

Hepatitis B virus (HBV) infection may be complicated by extrahepatic manifestations such as polya... more Hepatitis B virus (HBV) infection may be complicated by extrahepatic manifestations such as polyarteritis nodosa (PAN), glomerulonephritis, polymyositis, and dermatitis, but the etiology of these processes is not yet clear. HBV replication has been demonstrated in a variety of extrahepatic tissues and cell types, but the possible pathogenetic role of extrahepatic HBV replication has not been fully explored in patients with extrahepatic manifestations of HBV infection. In this case series, immunohistochemistry and in situ hybridization studies were performed on extrahepatic tissues from one HBsAg-positive patient with PAN and another HBsAg-positive patient with polymyositis, using HBsAg-seronegative control subjects with the same vasculitic disorders as controls. Tissue samples from the two study patients had detectable HBV RNA, replicative intermediates of HBV DNA, as well as HBsAg and HBcAg localized to vascular endothelium. In contrast, HBsAg-negative control patients had no tissue reactivity. Our results suggest that patients with HBV-related extrahepatic disease have evidence of viral replication in damaged extrahepatic endothelial tissues. While further studies would be required to support a hypothesis of causality, these findings suggest a role for both immune complex deposition and viral replication within diseased endothelial tissue in the pathogenesis of these poorly understood extrahepatic disorders.

A randomized, controlled crossover trial of ondansetron in patients with primary biliary cirrhosis and fatigue

Hepatology, 2005

Fatigue is common in primary biliary cirrhosis (PBC). Altered central serotonergic neurotransmiss... more Fatigue is common in primary biliary cirrhosis (PBC). Altered central serotonergic neurotransmission may be involved in its pathogenesis. This multicenter, randomized, double-blind, placebo-controlled, crossover trial evaluated the efficacy of ondansetron, a selective 5-HT3 receptor subtype antagonist, for treating fatigue in PBC. A crossover design was chosen, allowing subjects to serve as their own controls-appropriate to evaluate fatigue, a subjective symptom. Sixty patients with clinically stable PBC, a Fatigue Severity Score (FSS) > 4, and no other identifiable cause for fatigue were enrolled. Subjects were randomized to receive ondansetron (4 mg) or placebo orally 3 times daily for 4 weeks (period 1). Subjects then crossed over, after a minimum 1-week washout period, for a further 4 weeks of ondansetron or placebo (period 2). Fatigue was measured at the beginning and end of each period by using the FSS and Fatigue Impact Scale (FIS). Six patients withdrew; the remaining 54 subjects had a mean baseline FSS of 5.55 (+/-0.1). Response to study medication in period 1 versus period 2 was not uniform; thus, it was necessary to analyze the trial periods separately. In period 1, there was no significant additional fatigue reduction on ondansetron over placebo. During period 2, FSS and FIS decreased significantly on ondansetron versus placebo (P = .001). However, period 2 results were invalidated because drug side effects unblinded subjects (constipation affected 63.0% of patients taking ondansetron, versus 13.3% on placebo). In conclusion, ondansetron administration did not confer clinically significant fatigue reduction when compared with placebo in our study population.

Gastrointestinal Endoscopy, 2004

Background: The aim of this study was to determine whether digital video is suitable for the docu... more Background: The aim of this study was to determine whether digital video is suitable for the documentation of colonoscopy. Standards are required for the visual documentation of endoscopic findings and to optimize image quality while limiting file size and bandwidth requirements. Methods: Video recordings of colonoscopy procedures were encoded using a common video compression method at selected data rates and resolutions. Twelve reviewers were selected, each of whom was assigned 8 video review sessions, each consisting of 5 colonoscopy procedures. The reviewers rated the following: level of confidence that the cecum was demonstrated, subjective quality of the video compared with actual videocolonoscopy, and whether the video was of ''diagnostic quality.'' Results: Reviewers were confident that the cecum was demonstrated in all cases except at the lowest data rate. The 1.0 Mbps standard interchange format video provided an optimal balance between quality and file size. Conclusions: For the documentation of colonoscopy, 1.0 Mbps is acceptable and results in a file size of 7.5 Mbytes/min, which is manageable for most modern hospital and telehealth networks.

CPOE with evidence-based clinical decision support improves patient outcomes: the journey to date for a Canadian hospital

Healthcare quarterly (Toronto, Ont.), 2014