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I n 2009, Krum et al 1 described a new catheter-based treatment of essential hypertension resistant to multiple antihypertensive drugs. They performed bilateral, percutaneous, catheter-based radiofrequency (RF) ablation of the renal artery in 45 patients. At 9 months after the procedure, a 24/11-mm Hg mean decrease in systemic blood pressure (BP) was measured in 20 patients. More recently, the Symplicity HTN investigators reported the treatment of 153 patients with RF catheter ablation of the renal artery at 19 medical centers.2,3 At 12 months after the procedure, BP measured in an ambulatory setting was lowered by a mean of 23/11 mm Hg in 64 patients and decreased further by 32/14 mm Hg at 24 months in 18 patients.The putative mechanisms of RF catheter ablation of the renal artery are attributed to an attenuation of sympathetic nervous activity.1-4 However, the details of the functional effects of RF ablation of the renal artery and a marker of the optimal target site and end point of an effective RF application have not been clearly identified. To further study the role of the renal autonomic nerves and RF ablation of the renal artery in the regulation of BP, we electrically stimulated the renal arterial nerves before and after RF catheter ablation from inside the renal artery in dogs. Methods Animal PreparationThis study was approved by the animal studies subcommittee of our institutional review board and was in compliance with the guidelines of the National Institutes of Health for the care and use of laboratory animals. The experiments were performed in 8 intubated and artificially ventilated beagles, weighing between 10.5 and 13.0 kg, anesthetized with a 17.5-mg/kg IV bolus, followed by a maintenance dose of 3.0 to 5.0 mg/kg per hour of sodium thiopental. Abstract-Radiofrequency (RF) catheter ablation of the renal artery is therapeutic in patients with drug-refractory essential hypertension. This study was designed to examine the role of the renal autonomic nerves and of RF application from inside the renal artery in the regulation of blood pressure (BP). An open irrigation catheter was inserted into either the left or right renal artery in 8 dogs. RF current (17±2 watts) was delivered to one renal artery. Electrical autonomic nerve stimulation was applied to each renal artery before and after RF ablation. BP, heart rate, indices of heart rate variability, and serum catecholamines were analyzed. Before RF ablation, electrical autonomic nerve stimulation of either renal artery increased BP from 150±16/92±15 to 173±21/105±16 mm Hg. After RF ablation, BP increased similarly when the nonablated renal artery was electrically stimulated, although the rise in BP was attenuated when the ablated renal artery was stimulated. Serum catecholamines and sympathetic nerve indices of heart rate variability increased when electrical autonomic nerve stimulation was applied before RF ablation and to the nonablated renal artery after RF ablation, although it changed minimally when the ablated renal artery was stimulated, sugg...

Six cases of type A gastritis associated with multiple carcinoids and/or endocrine cell micronests (ECM) in the atrophic fuindic mucosa were examined light microscopically, immunohistochemically, and ultrastructurally. The ECM and carcinoids were mainly composed of enterochromaffin-like (ECL) cells. The cells were hyperplastic only in the atrophic fundic glands and pseudopyloric glands, but not in the intestinal metaplastic gland. It is suggested that the development of both the ECM and the carcinoids is highly related to the atrophic change of the fundic mucosa and a trophic action of subsequently raised serum gastrin in type A gastritis and that the both lesions arise from the pseudopyloric glands or atrophic fundic glands. In addition, the definition of neoplastic ECM (microcarcinoid) of the stomach was made with comparative study on both the cases with ECM and multiple carcinoids and the cases with ECM alone.

This randomized clinical trial assesses whether etoposide plus cisplatin or irinotecan plus cisplatin is a more effective treatment regimen in terms of overall survival in patients with advanced neuroendocrine carcinoma of the digestive system.