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Dive into the research topics where Galen Perdikis is active.

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Featured researches published by Galen Perdikis.


Annals of Surgery | 1994

Laparoscopic Nissen fundoplication is an effective treatment for gastroesophageal reflux disease.

Ronald A. Hinder; Charles J. Filipi; Gerold J. Wetscher; Patricia Neary; Tom R. DeMeester; Galen Perdikis

ObjectveThe open Nissen fundoplication is effective therapy for gastroesophageal reflux disease. In this study, the outcomes in 198 patients treated with the laparoscopic Nissen fundoplication was evaluated for up to 32 months after surgery to ascertain whether similar positive results could be obtained. Summary Background DataTo ensure surgical success, patients were required to have mechanically defective sphincters on manometry and increased esophageal acid exposure on 24-hour pH monitoring. The patients either had severe complications of gastroesophageal reflux disease or had failed medical therapy. These requirements have been found to be necessary to ensure a successful surgical outcome. MethodsThe disease was complicated by ulceration (46), stricture (25) and Barretts esophagus (33). Patients underwent standard Nissen fundoplications identical in every detail to open procedures except that the procedures were carried out by the laparoscopic route. ResultsPerioperative complications included gastric or esophageal perforation (3), pneumothorax (2), bleeding (2), breakdown of crural repair (2) and periesophageal abscess (1). The only mortality occurred from a duodenal perforation. Six patients required conversion to the open procedure. The median hospital stay was 3 days. One hundred patients were observed for follow-up for 6 to 32 months (median 12 months), with outcomes similar to the open Nissen fundoplication. Further surgery was required for two patients who had recurrent gastroesophageal reflux and one who developed an esophageal stricture. Ninety-seven percent are satisfied with their decision to have the operation. ConclusionsThe laparoscopic Nissen fundoplication can be carried out safely and effectively with similar positive results to the open procedure and with all of the advantages of the minimally invasive approach.


Free Radical Biology and Medicine | 1995

Free radical production in nicotine treated pancreatic tissue

Gerold J. Wetscher; Manashi Bagchi; Debasis Bagchi; Galen Perdikis; Paul R. Hinder; Karl Glaser; Ronald A. Hinder

The ability of nicotine to induce oxidative stress in the pancreatic tissue of rats was investigated. Homogenized pancreatic tissue of Sprague-Dawley rats was incubated with nicotine in a dose of 200 ng/mg protein/ml for 15, 30, 45, and 60 min or was incubated for 30 min with nicotine in a dose of 50, 100, 200, 400, and 800 ng/mg protein/ml. Pancreatic tissue was also incubated with 200 ng/mg protein/ml nicotine with or without the scavengers superoxide dismutase (SOD), catalase, SOD+catalase, inactivated SOD, inactivated catalase, or albumin. Incubation with 0.9% NaCl served as control. There was a positive correlation between the duration of nicotine incubation and chemiluminescence (r = 0.6) or lipid peroxidation (r = 0.71) and also between the nicotine dose and chemiluminescence (r = 0.54) or lipid peroxidation (r = 0.66). Thirty minutes incubation of pancreatic tissue with nicotine in a dose of 200 ng/mg protein/ml increased chemiluminescence 5 fold and lipid peroxidation 2.5 fold. This response was dampened by SOD or catalase and abolished by SOD+catalase. Inactivated enzymes or albumin had no scavenging effect. These results demonstrate that nicotine causes oxidative stress to the pancreatic tissue of rats.


American Journal of Surgery | 1995

Reflux esophagitis in humans is mediated by oxygen-derived free radicals☆

Gerold J. Wetscher; Ronald A. Hinder; Debasis Bagchi; Paul R. Hinder; Manashi Bagchi; Galen Perdikis; Thomas R. McGinn

BACKGROUND Oxidative stress in reflux esophagitis was investigated before and after antireflux surgery. PATIENTS AND METHODS Oxidative stress was studied in the distal and proximal esophagus of control patients (without esophagitis, but with other gastrointestinal disorders), of patients with various grades of esophagitis (including Barretts esophagus), and in patients who had a Nissen fundoplication. Oxidative stress was assessed by chemiluminescence, lipid peroxidation (LP), and by measuring superoxide dismutase (SOD). RESULTS Chemiluminescence and LP increased with the degree of esophagitis and was highest in patients with Barretts esophagus; SOD decreased with damage, except in cases of Barretts esophagus associated with mild esophagitis. Chemiluminescence and LP in reflux patients were higher in the distal than in the proximal esophagus, and SOD was lower, whereas no such difference was found in controls. Findings after Nissen fundoplication were similar to those of controls. CONCLUSIONS Reflux esophagitis is mediated by free radicals depleting SOD. Barretts esophagus is a severe form of oxidative damage; in some patients, high SOD levels may prevent severe esophagitis. Antireflux surgery prevents oxidative damage.


Journal of Gastrointestinal Surgery | 1997

Laparoscopic toupet fundoplication for gastroesophageal reflux disease with poor esophageal body motility

Richard J. Lund; Gerold J. Wetcher; Frank Raiser; Karl Glaser; Galen Perdikis; Michael Gadenstätter; Natsuya Katada; Charles J. Filipi; Ronald A. Hinder

Impaired esophageal body motility is a complication of chronic gastroesophageal reflux disease (GERD). In patients with this disease, a 360-degree fundoplication may result in severe postoperative dysphagia. Forty-six patients with GERD who had a weak lower esophageal sphincter pressure and a positive acid reflux score associated with impaired esophageal body peristalsis in the distal esophagus (amplitude <30 mm Hg and >10% simultaneous or interrupted waves) were selected to undergo laparoscopic Toupet fundoplication. They were compared with 16 similar patients with poor esophageal body function who underwent Nissen fundoplication. The patients who underwent Toupet fundoplication had less dysphagia than those who had the Nissen procedure (9% vs. 44%;P=0.0041). Twenty-four-hour ambulatory pH monitoring and esophageal manometry were repeated in 31 Toupet patients 6 months after surgery. Percentage of time of esophageal exposure to pH <4.0, DeMeester reflux score, lower esophageal pressure, intra-abdominal length, vector volume, and distal esophageal amplitude all improved significantly after surgery. Ninety-one percent of patients were free of reflux symptoms. The laparoscopic Toupet fundoplication provides an effective antireflux barrier according to manometric, pH, and symptom criteria. It avoids potential postoperative dysphagia in patients with weak esophageal peristalsis and results teria. It avoids potential postoperative dysphagia in patients with weak esophageal peristalsis and results in improved esophageal body function 6 months after, surgery.


Digestive Diseases and Sciences | 1995

Esophagitis in sprague-dawley rats is mediated by free radicals

Gerold J. Wetscher; Galen Perdikis; David H. Kretchmar; Ronald Stinson; Debasis Bagchi; Elizabeth J. Redmond; Thomas E. Adrian; Ronald A. Hinder

Free radical-mediated esophagitis was studied during duodenogastroesophageal reflux (mixed reflux) or acid reflux in rats. The influence of reflux on esophageal glutathione levels was also examined. Mixed reflux caused more gross mucosal injury than acid reflux. Gross mucosal injury occurred in the mid-esophagus. Total glutathione (GSH) in the esophageal mucosa of control rats was highest in the distal esophagus. The time course of esophageal GSH in rats treated by mixed reflux showed a significant decrease 4 hr after initiation of reflux, followed by a significant increase from the 12th hour on. Mucosal GSH was increased in both reflux groups after 24 hr but significantly more so in the mixed than in the acid reflux group. The free radical scavenger superoxide dismutase (SOD) prevented esophagitis and was associated with decreased GSH levels. GSH depletion by buthionine sulfoximine (BSO) prevented esophagitis and stimulated SOD production in the esophageal mucosa. It is concluded that gastroesophageal reflux is associated with oxidative stress in the esophageal mucosa. The lower GSH levels in the mid-esophagus may predispose to damage in this area. Duodenogastroesophageal reflux causes more damage than pure acid reflux. Oxidative stress leads to GSH depletion of the esophageal mucosa in the first few hours following damage but then stimulates GSH production. GSH depletion by BSO does not worsen esophagitis since it increases the esophageal SOD concentration.


Digestive Diseases and Sciences | 1995

Free radical scavengers prevent reflux esophagitis in rats.

Gerold J. Wetscher; Paul R. Hinder; Debasis Bagchi; Galen Perdikis; Elizabeth J. Redmond; Karl Glaser; Thomas E. Adrian; Ronald A. Hinder

Free radical damage in reflux esophagitis of rats induced by 24-hr duodenojejunal ligation was studied. Oxygen free radicals were selectively blocked. Groups were: sham operation, reflux, reflux+superoxide dismutase (SOD), catalse, dimethylthiourea, allopurinol, and inactivated SOD or inactivated catalase alone or in the combination SOD+catalase or SOD+catalase+dimethylthiourea+allopurinol. Macroscopic esophagitis was inhibited only by SOD, alone or in combination with other agents. Esophageal mucosal lipid peroxidation was 10-fold increased in the reflux group compared to the sham group (P<0.05). This response was damped by SOD>catalase (P<0.05) but not by the inactivated enzymes, dimethylthiourea or allopurinol. SOD+catalase showed no significant improvement on SOD alone. Total inhibition of lipid peroxidation was achieved by combining all scavengers. Total glutathione (GSH) in the esophageal mucosa was stimulated by reflux. This response was inhibited by scavengers equivalent to their efficacy in preventing lipid peroxidation. It is concluded that reflux esophagitis is associated with free radical release with O2− being the main source. Free radicals appear to stimulate GSH production in this prolonged oxidative stress.


American Journal of Surgery | 1997

Respiratory symptoms in patients with gastroesophageal reflux disease following medical therapy and following antireflux surgery.

G. J. Wetscher; Karl Glaser; Ronald A. Hinder; Galen Perdikis; Paul J. Klingler; Tanja Bammer; Thomas Wieschemeyer; Gerhard Schwab; Anton Klingler; Rudolph Pointner

BACKGROUND It is not known whether antireflux surgery is more effective than medical therapy to control respiratory symptoms (RS) in gastroesophageal reflux disease (GERD). METHODS In 21 GERD patients with RS, reflux was assessed by endoscopy, manometry, and pH monitoring. Patients had proton pump inhibitor therapy and cisapride for 6 months. After GERD relapsed following withdrawal of medical therapy, 7 patients with normal esophageal peristalsis had a laparoscopic Nissen fundoplication and 14 with impaired peristalsis a Toupet fundoplication. Respiratory symptoms were scored prior to treatment, at 6 months following medical therapy, and at 6 months after surgery. RESULTS Heartburn and esophagitis were effectively treated by medical and surgical therapy. Only surgery improved regurgitation. Respiratory symptoms improved in 18 patients (85.7%) following surgery and in only 3 patients (14.3%) following medical therapy (P <0.05). Esophageal peristalsis improved following the Toupet fundoplication. CONCLUSION Medical therapy fails to control reflux since it does not inhibit regurgitation. Surgery controls reflux and improves esophageal peristalsis, which contributes to its superiority over medical therapy in the treatment of RS associated with GERD.


Chemico-Biological Interactions | 1997

Interrelationship between cellular calcium homeostasis and free radical generation in myocardial reperfusion injury

Debasis Bagchi; Gerold J. Wetscher; Manashi Bagchi; Paul R. Hinder; Galen Perdikis; Sidney J. Stohs; Ronald A. Hinder; Dipak K. Das

This review describes the interrelationship between two important biological factors, intracellular calcium overloading and oxygen-derived free radicals, which play a crucial role in the pathogenesis of myocardial ischemic reperfusion injury. Free radicals are generated during the reperfusion of ischemic myocardium, and polyunsaturated fatty acids in the membrane phospholipids are the likely targets of the free radical attack. On the other hand, activation of phospholipases can provoke the breakdown of membrane phospholipids which results in the activation of arachidonate cascade leading to the generation of prostaglandins, and oxygen free radicals can be produced during the interconversion of the prostaglandins. In conclusion, it has been emphasized that the two seemingly different causative factors of reperfusion injury, intracellular calcium overloading and free radical generation are, in fact, highly interrelated.


Surgical Clinics of North America | 1997

Management of the failed antireflux operation.

Ronald A. Hinder; Paul J. Klingler; Galen Perdikis; Stephen L. Smith

A further operation is required in a small proportion of patients who have had prior antireflux surgery. This has a surprisingly good chance for success in appropriately evaluated patients. The surgeon must make very specific decisions regarding the surgical approach. The use of laparoscopy for redo surgery is being defined.


Digestive Diseases and Sciences | 1999

Gastric acid blockade with omeprazole promotes gastric carcinogenesis induced by duodenogastric reflux.

Gerold J. Wetscher; Ronald A. Hinder; Tom Smyrk; Galen Perdikis; Thomas E. Adrian; Christoph Profanter

Duodenogastric reflux (DGR) in rats causesgrowth stimulation of the foregut mucosa that ispotentiated by gastric acid blockade. It was the aim ofthis study to investigate if DGR with gastric acidblockade has a higher incidence of carcinomas of theforegut than DGR alone. DGR was induced in 40Sprague-Dawley rats using a split gastroenterostomy. Acardiomyotomy was performed across the gastroesophagealjunction, inducing reflux into the esophagus. Twenty ofthese rats received omeprazole postoperatively. Afterone year 18 rats (90%) with DGR + omeprazole treatmentand 7 rats (35%) with DGR alone developed adenocarcinoma of the stomach (P < 0.05). None of the ratsdeveloped esophageal cancer, but esophageal mucosalhyperplasia was more pronounced in rats receivingomeprazole. Control rats, treated with omeprazole, did not develop carcinomas of the foregut. Inconclusion, gastric acid blockade enhanced DGR-inducedcarcinogenesis of the stomach and promotes growthstimulation of the esophageal mucosa.

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Karl Glaser

University of Innsbruck

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Debasis Bagchi

Creighton University Medical Center

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