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Anthony N Kalloo

Publications and source records attributed to Anthony N Kalloo.

23 records · Page 2Linked to original sources
PubMed2003

Intrasphincteric nitric oxide reduces sphincter of Oddi motility in an endoscopic porcine model.

Nitric oxide (NO), a potent nonadrenergic, noncholinergic mediator of gastrointestinal smooth muscle, causes relaxation of the category I pump like sphincter of Oddi (SO) (eg, opossum, rabbit) and category II resistor like SO (eg, pig, human). Topical administration of a NO donor induces SO relaxation in humans, and parenteral administration of sodium nitroprusside (SNP) decreases sphincter contractility in pig SO. The aim of this study is to evaluate the effect of intrasphincteric SNP injection on pig SO. Under general anesthesia, two pigs received intrasphincteric saline injection (1 ml) and six pigs received intrasphincteric SNP (0.5 microg/ml) injection into the SO. All injections were administered into the major papilla using a 5-mm sclerotherapy needle through the duodenoscope. Endoscopic biliary manometry was performed using the standard station pull-through technique and SO pressures were recorded before and after injection. Intrasphincteric saline injection did not significantly change the mean SO motility index (MI) (197 vs 198). However, intrasphincteric SNP reduced both the mean SO basal pressure (P = 0.002) and the mean SO MI (226 vs 109; P = 0.002). The effect of intrasphincteric SNP lasted up to 45 min and did not cause significant lowering of systemic blood pressure. This is the first study to demonstrate that intrasphincteric SNP results in significant reduction in both SO basal pressure and SO MI in the porcine model. The endoscopic intrasphincteric administration of NO donor drugs is technically feasible and without observed systemic side effects.

Animals↗
PubMed2003

Endoscopic cryotherapy for the treatment of bleeding mucosal vascular lesions of the GI tract: a pilot study.

BACKGROUND: Thermal therapy is the cornerstone of endoscopic treatment of bleeding mucosal lesions of the GI tract. However, there is a 20% failure rate and contact devices may be cumbersome in the treatment of large bleeding areas. A pilot study was conducted to evaluate the safety and efficacy of endoscopic cryotherapy for bleeding mucosal vascular lesions. METHODS: Patients with recurrent bleeding from diffuse mucosal vascular lesions were treated with cryotherapy and had endoscopic and clinical follow-up. RESULTS: Twenty-six patients with gastric and duodenal arteriovenous malformations (n = 7), watermelon stomach (n = 7), radiation-induced gastritis (n = 5), and radiation-induced proctitis (n = 7) were treated with mean of 3.4 (1.6) sessions. The best results were achieved in patients with radiation-induced proctitis, with cessation of bleeding in all 7 patients. Cryotherapy was also effective in patients with multiple arteriovenous malformations (86%) and watermelon stomach (71%). It was less effective in patients with radiation-induced damage to stomach and duodenum, although all patients in this group were debilitated because of disseminated malignancy. CONCLUSIONS: Cryotherapy is a safe and effective treatment for bleeding from diffuse mucosal lesions of the GI tract. Bleeding from radiation-induced proctitis and multiple arteriovenous malformations is particularly responsive to endoscopic cryotherapy.

Aged↗
PubMed2002

Accuracy and reliability of the endoscopic classification of portal hypertensive gastropathy.

BACKGROUND: There is no consensus regarding the endoscopic classification of the severity of portal hypertensive gastropathy. This study compared the accuracy and reproducibility of the 2-category classification system (2-CCS) with the 3-category classification system (3-CCS). METHODS: Ninety-eight endoscopic pictures of portal hypertensive gastropathy and 22 of nonspecific gastritis were selected. Eight duplicate sets were generated, each in a different random order. These were shown to 6 experienced endoscopists during 2 sessions 1 week apart with 4 slide sets at each session. Each picture was scored by using either the 2-CCS or 3-CCS. Kappa statistics and percent agreement were used to estimate the reproducibility and agreement. RESULTS: The mean percentage agreement among the 4 separate readings for each observer was significantly lower for the 3-CCS compared with the 2-CCS (mean [standard deviation] = 33.5% [8.9%] vs. 64.9% [9.1%]; p = 0.0001). The mean (SD) interobserver kappa values were 0.44 (0.03) for the 3-CCS and 0.52 (0.04) for the 2-CCS (p = 0.02), and the respective intraobserver kappa values were 0.43 (0.1) and 0.63 (0.06) (p = 0.002). CONCLUSIONS: Even though both the 2-CCS and 3-CCS have substantial limitations with regard to specificity and reliability, there were better agreement and reproducibility with the simpler classification system for portal hypertensive gastropathy.

Gastric Mucosa↗