Gregory O'Grady

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BACKGROUND The significance of gastric dysrhythmias remains uncertain. Progress requires a better understanding of dysrhythmic behaviors, including the slow wave patterns that accompany or promote them. The aim of this study was to use high-resolution spatiotemporal mapping to characterize and quantify the initiation and conduction of porcine gastric(More)
One approach for achieving runtime adaptability in software is to use application frameworks that are tailored for the development of self-adaptive systems. In this paper, we present the <i>Graph-based Runtime Adaptation Framework</i> (GRAF), which enables adaptivity by creating, managing, and interpreting graph-based models of software at runtime. Having a(More)
BACKGROUND & AIMS Interstitial cells of Cajal (ICC) generate slow waves. Disrupted ICC networks and gastric dysrhythmias are each associated with gastroparesis. However, there are no data on the initiation and propagation of slow waves in gastroparesis because research tools have lacked spatial resolution. We applied high-resolution electrical mapping to(More)
BACKGROUND & AIMS Chronic unexplained nausea and vomiting (CUNV) is a debilitating disease of unknown cause. Symptoms of CUNV substantially overlap with those of gastroparesis, therefore the diseases may share pathophysiologic features. We investigated this hypothesis by quantifying densities of interstitial cells of Cajal (ICCs) and mapping slow-wave(More)
Slow waves coordinate gastric motility, and abnormal slow-wave activity is thought to contribute to motility disorders. The current understanding of normal human gastric slow-wave activity is based on extrapolation from data derived from sparse electrode recordings and is therefore potentially incomplete. This study employed high-resolution (HR) mapping to(More)
BACKGROUND The pig is a popular model for gastric electrophysiology studies. However, its normal baseline gastric activity has not been well characterized. High-resolution (HR) mapping has recently enabled an accurate description of human and canine gastric slow wave activity, and was employed here to define porcine gastric slow wave activity. METHODS(More)
BACKGROUND Evidence from animal studies suggests that gastrointestinal motility is impaired in acute pancreatitis. Enteral nutrition, and more specifically nasogastric tube feeding, has emerged as a key treatment modality in patients with acute pancreatitis, but its effect on motility has not been investigated in this setting. The aim was to validate the(More)
BACKGROUND Until recently, investigations of the normal patterns of motility of the healthy human colon have been limited by the resolution of in vivo recording techniques. METHODS We have used a new, high-resolution fiber-optic manometry system (72 sensors at 1-cm intervals) to record motor activity from colon in 10 healthy human subjects. KEY RESULTS(More)
BACKGROUND Colorectal cancer surgery, and rectal surgery in particular, has benefited from increased regionalization and subspecialization. With increasing focus on dedicated colorectal units in tertiary centres, the role of smaller provincial hospitals in colorectal cancer surgery has been of topical interest. Little data of relevance to this issue are(More)
AIM The high incidence rates of colorectal cancer (CRC) in New Zealand (NZ) are well publicised. Minimal information is available comparing national extent of this disease at time of diagnosis with other countries, especially countries now performing screening for CRC. Just how late do our cancers present? What is the difference compared with other(More)