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Dive into the research topics where Alex Escalona is active.

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Featured researches published by Alex Escalona.


Surgical Endoscopy and Other Interventional Techniques | 2009

Open label, prospective, randomized controlled trial of an endoscopic duodenal-jejunal bypass sleeve versus low calorie diet for pre-operative weight loss in bariatric surgery

Michael Tarnoff; Leonardo Rodriguez; Alex Escalona; Almino Cardoso Ramos; Manoel Galvao Neto; Munir Alamo; E. Reyes; Fernando Pimentel; Luis Ibáñez

BackgroundThe duodenal-jejunal bypass sleeve (DJBS) has been shown to achieve a completely endoscopic duodenal exclusion without the need for stapling. This report is the first randomized controlled trial for weight loss.MethodsIn a 12-week, prospective, randomized study, subjects received either a low fat diet and the DJBS or a low fat diet control (no device). Twenty-five patients were implanted with the device and 14 received the control. The groups were demographically similar. Both groups received counseling at baseline only, which consisted of a low calorie diet, and exercise/behavior modification advice. No additional counseling occurred in either group. Measurements included starting and monthly body weight and serum blood tests. The device group also had a plain abdominal film post implant, a monthly KUB and a 4-week post explant EGD.ResultsTwenty device (80%) subjects maintained the DJBS without a significant adverse event for the 12-week duration. At 12 weeks, the mean excess weight loss was 22% and 5% for the device and control groups, respectively (p < 0.001). Five subjects (20%) were endoscopically explanted early secondary to upper GI (UGI) bleeding (n = 3), anchor migration (n = 1) and sleeve obstruction (n = 1). The UGI bleeding occurred at a mean of 13.8 days post implant. EGD was performed in each of these cases with no distinct bleeding source identified. No blood transfusion was required. The migration occurred on day 47 and manifested as abdominal pain. The subject with the sleeve obstruction presented with abdominal pain and vomiting on day 30. Eight subjects (40%) underwent the 4 week post explant EGD at which time mild degrees of residual duodenal inflammation was noted.ConclusionThe DJBS achieves noninvasive duodenal exclusion and short term weight loss efficacy. Longer term randomized controlled sham trials for weight loss and treatment of T2DM are underway.


Annals of Surgery | 2012

Weight Loss and Metabolic Improvement in Morbidly Obese Subjects Implanted for 1 Year With an Endoscopic Duodenal-Jejunal Bypass Liner

Alex Escalona; Fernando Pimentel; Allan Sharp; Pablo Becerra; Milenko Slako; Dannae Turiel; Rodrigo Muñoz; Claudia Bambs; Sergio Guzmán; Luis Ibáñez; Keith S. Gersin

Objective:To evaluate safety, weight loss, and cardiometabolic changes in obese subjects implanted with the duodenal-jejunal bypass liner (DJBL) for 1 year. Background:The DJBL is an endoscopic implant that mimics the duodenal-jejunal bypass component of the Roux-en-Y gastric bypass. Previous reports have shown significant weight loss and improvement in type 2 diabetes for up to 6 months. Methods:Morbidly obese subjects were enrolled in a single arm, open label, prospective trial and implanted with the DJBL. Primary endpoints included safety and weight change from baseline to week 52. Secondary endpoints included changes in waist circumference, blood pressure, lipids, glycemic control, and metabolic syndrome. Results:The DJBL was implanted endoscopically in 39 of 42 subjects (age: 36 ± 10 years; 80% female; weight: 109 ± 18 kg; BMI: 43.7 ± 5.9 kg/m2); 24 completed 52 weeks of follow-up. Three subjects could not be implanted due to short duodenal bulb. Implantation time was 24 ± 2 minutes. There were no procedure-related complications and there were 15 early endoscopic removals. In the 52-week completer population, total body weight change from baseline was −22.1 ± 2.1 kg (P < 0.0001) corresponding to 19.9 ± 1.8% of total body weight and 47.0 ± 4.4% excess of weight loss. There were also significant improvements in waist circumference, blood pressure, total and low-density lipoprotein cholesterol, triglycerides, and fasting glucose. Conclusions:The DJBL is safe when implanted for 1 year, and results in significant weight loss and improvements in cardiometabolic risk factors. These results suggest that this device may be suitable for the treatment of morbid obesity and its related comorbidities. This study was registered at www.clinicaltrials.gov (NCT00985491).


Obesity Surgery | 2005

Gastric Cancer after Roux-en-Y Gastric Bypass

Alex Escalona; Sergio Guzmán; Luis Ibáñez; Luis Meneses; Alvaro Huete; Antonieta Solar

Roux-en-Y gastric bypass (RYGBP) is one of the most commonly performed surgical procedures for morbid obesity. Several complications that may develop in the short- and long-term have been reported. We present a patient who presented with cancer in the bypassed stomach 8 years after RYGBP. Although the development of this lesion is rare and only a few cases have been reported, there are aspects worthy of discussion. Several monitoring, diagnostic and therapeutic alternatives are analyzed.


Surgery for Obesity and Related Diseases | 2010

Endoscopic removal of eroded adjustable gastric band: lessons learned after 5 years and 78 cases

Manoel Galvao Neto; Almino Cardoso Ramos; Josemberg Marins Campos; Abel H. Murakami; Marcelo Falcão; Eduardo G. de Moura; Luis Fernando Evangelista; Alex Escalona; Natan Zundel

BACKGROUND One of the complications of laparoscopic adjustable gastric banding is intragastric erosion, leading to a revisional procedure to remove the band. Our aim was to present the procedure and results of endoscopic band removal in a 5-year multicenter experience from the Gastro Obeso Center and Universidade de São Paulo, São Paulo, and Universidade Federal de Pernambuco, Recife, Brazil. METHODS From 2003 to 2008, 82 patients were diagnosed with band erosion. The clinical data concerning the endoscopic procedure were prospectively recorded and retrospectively reviewed. RESULTS The average preoperative body mass index was 43.2 kg/m(2) (range 34-50). At the diagnosis of intragastric erosion, the body mass index was 24-41 kg/m(2) (average 31.8). The erosion occurred an average of 16.3 months (range 6-36) postoperatively. The symptoms included pain in 25 (31%), port infection in 21 patients (27%), and weight regain in 20 (25%), and 12 patients (15%) were asymptomatic. Endoscopic removal was possible for 78 patients (95%). In 85% of patients, the band was removed in the first session, with an average duration of 55 minutes (range 25-150). Five cases of pneumoperitoneum occurred after the procedure. Of these, 3 were treated conservatively, 1 was treated by laparoscopy, and 1 was treated by abdominal puncture using the Veress needle. CONCLUSION Endoscopic removal of eroded laparoscopic adjustable gastric banding is safe and effective. It can be used as a first choice procedure in clinical practice.


Obesity Surgery | 2004

Wernicke's Encephalopathy after Roux-en-Y Gastric Bypass

Alex Escalona; Gustavo Pérez; Francisca León; Catherine Volaric; Patricio Mellado; Luis Ibáñez; Sergio Guzmán

Complications of bariatric operations include the development of nutritional deficiencies. If protracted vomiting is added, severe vitamin depletion could arise such as thiamine deficiency, resulting in the development of Wernickes encephalopathy (WE). This article describes the rapid onset of WE in a 6-week postoperative morbidly obese woman. Because the occurrence of micronutrient deficiencies is infrequent, although reports are increasing, symptoms may be misdiagnosed leading to possible irreversible effects on the central nervous system. The importance of a prompt diagnosis of this serious complication and of adequate therapy is emphasized.


Surgery for Obesity and Related Diseases | 2010

Initial human experience with restrictive duodenal-jejunal bypass liner for treatment of morbid obesity

Alex Escalona; Ricardo Yañez; Fernando Pimentel; Manoel Galvão; Almino Cardoso Ramos; Dannae Turiel; Camilo Boza; Diego Awruch; Keith S. Gersin; Luis Ibáñez

BACKGROUND The duodenal-jejunal bypass liner is an endoscopically placed and removable intestinal liner that creates a duodenal-jejunal bypass, leading to diabetes improvement and weight loss. The aim of the present study was to evaluate the clinical effects and safety of the duodenal-jejunal bypass liner combined with a restrictor orifice (flow restrictor). METHODS The device was endoscopically implanted in 10 patients (body mass index 40.8 +/- 4.0 kg/m(2)) and removed after 12 weeks. Dilation of the restrictor orifice was performed as clinically indicated with a 6-, 8-, or 10-mm diameter through-the-scope balloon. The measured outcomes included the percentage of excess weight loss, total weight loss, adverse events, and gastric emptying (GE) at baseline, weeks 4 and 12 of implantation, and 3-5 months after device removal. GE was measured by scintigraphy at 1, 2, and 4 hours after implantation. RESULTS The percentage of excess weight loss and total weight loss at explantation was 40% +/- 3% (range 21-64%) and 16.7 +/- 1.4 kg (range 12.0-26.0), respectively. The 4-hour GE was 98% +/- 1% at baseline, 72% +/- 6% at 4 weeks (P = 0.001 versus baseline), and 84% +/- 5% at 12 weeks (P <.05 versus baseline). After explantation, the rate of GE returned to normal in 7 of 8 subjects, but remained slightly delayed in 1 subject (84% at 4 hours). Episodes of nausea, vomiting, and abdominal pain required endoscopic dilation of the restrictor orifice with a 6-mm through-the-scope balloon in 7 patients and a 10-mm balloon in 1, with no clinically significant adverse events. CONCLUSION Endoscopic implantation of a combination flow restrictor and duodenal-jejunal bypass liner induced substantial weight loss. The implanted patients exhibited delayed GE that was reversed after device removal.


Surgery for Obesity and Related Diseases | 2010

Laparoscopic Roux-en-Y gastric bypass versus laparoscopic adjustable gastric banding: five years of follow-up

Camilo Boza; Cristian Gamboa; Diego Awruch; Gustavo Pérez; Alex Escalona; Luis Ibáñez

BACKGROUND Bariatric surgery is an effective treatment for morbid obesity. Laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic adjustable gastric banding (LAGB) are commonly performed procedures. The aim of the present study was to evaluate and compare the long-term outcomes after LRYGB and LAGB. METHODS We studied the data from a prospective database of all patients undergoing LRYGB or LAGB with 5 years of follow-up. RESULTS From July 2001 to September 2003, 91 and 62 patients underwent LRYGB and LAGB, respectively. Of these patients, 73.6% of the LRYGB and 91.9% of the LAGB patients had 5 years of follow-up. Of the 91 and 62 patients, 89% and 82% were women, respectively. The mean age and body mass index was 34.5 ± 11.0 years and 39.6 ± 4.9 kg/m(2) for the LRYGB group and 38.4 ± 13.1 years and 35.8 ± 4.0 kg/m(2) for the LAGB group, respectively. The mean operative time was 150 ± 58 minutes for LYRGB and 73 ± 23 minutes for LAGB (P <.05). The conversion and reoperation rate was 8% and 4.3%, respectively, for the LRYGB group versus 0% for the LAGB group. Early postoperative complications were observed in 12 and 1 patient (P = .014) after LRYGB and LAGB, respectively. Late complications developed in 33 and 17 patients after LYRGB and LAGB, respectively (P = NS). The percentage of excess weight loss at 5 years postoperatively was 92.9% ± 25.6% and 59.1% ± 46.8% (P <.001) for LRYGB and LAGB, respectively. Surgical failure (percentage of excess weight loss <50%) at 5 years was 6% for LRYGB and 45.6% for LAGB. A late reoperation was needed in 24.1% of the LAGB patients. CONCLUSION A greater percentage of excess weight loss at 1 and 5 years was observed after LRYGB than LAGB. The LAGB group had a >40% rate of surgical failure and a 24.1% reoperation rate at 5 years of follow-up.


World Journal of Surgery | 2005

Prospective randomized study of T-tube versus biliary stent for common bile duct decompression after open choledocotomy.

Gustavo Pérez; Alex Escalona; Nicolás Jarufe; Luis Ibáñez; Paola Viviani; Carlos García; Carlos Benavides; José Salvadó

The T-tube has been the alternative of choice for decompression following common bile duct (CBD) exploration. The development of laparoscopic surgery has suggested using a biliary stent as an alternative to the T-tube following choledochotomy. The purpose of this prospective randomized study was to compare clinical results obtained from patients who underwent open CBD exploration using a biliary stent versus those from patients with a T-tube for decompression. Between September 2000 and June 2002 a total of 81 patients were randomly assigned to a biliary stent or a T-tube as the decompression method following choledochotomy. An open CBD exploration was performed when CBD stones were suspected, in both elective and emergency settings. The length of the postoperative hospital stay was 6.8 ± 4.7 days for patients with the T-tube and of 5.2 ± 3.3 days for, patients with the biliary stent (p = 0.19). Postoperative complications were observed in 13 patients (30 %) with the T-tube and in 4 patients (11% ) with the biliary stent (p = 0.03). One patient with a biliary stent was reoperated because of an intraabdominal abscess, and another patient was reoperated because of biliary peritonitis following T-tube removal. Three patients (7%) with a biliary stent and one patient (3%) with a T-tube were rehospitalized. There were no deaths. The T-tube and biliary stent were removed 27.1 ± 10.8 days and 34.9 ± 12.9 days after surgery, respectively (p = 0.24). The biliary stent is a safe alternative to the T-tube as a biliary decompression method following an open CBD exploration.


Liver International | 2011

Overexpression of 11β-hydroxysteroid dehydrogenase type 1 in visceral adipose tissue and portal hypercortisolism in non-alcoholic fatty liver disease.

Roberto Candia; Arnoldo Riquelme; Rene Baudrand; Cristian A. Carvajal; Mauricio Morales; Nancy Solís; Margarita Pizarro; Alex Escalona; Gonzalo Carrasco; Camilo Boza; Gustavo Pérez; Oslando Padilla; Jaime Cerda; Carlos E. Fardella; Marco Arrese

The enzyme 11β‐hydroxysteroid‐dehydrogenase type 1 (11β‐HSD1) catalyses the reactivation of intracellular cortisol. We explored the potential role of 11β‐HSD1 overexpression in visceral adipose tissue (VAT) in non‐alcoholic fatty liver disease (NAFLD) assessing sequential changes of enzyme expression, in hepatic and adipose tissue, and the occurrence of portal hypercortisolism in obese mice. 11β‐HSD1 expression was also assessed in tissues from obese patients undergoing bariatric surgery.


Metabolism-clinical and Experimental | 2011

Overexpression of hepatic 5α-reductase and 11β-hydroxysteroid dehydrogenase type 1 in visceral adipose tissue is associated with hyperinsulinemia in morbidly obese patients

Rene Baudrand; José Miguel Domínguez; Cristian A. Carvajal; Arnoldo Riquelme; Carmen Campino; Stefano Macchiavello; Milan Bozinovic; Mauricio Morales; Margarita Pizarro; Nancy Solís; Alex Escalona; Camilo Boza; Marco Arrese; Carlos E. Fardella

11-β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts cortisone to cortisol, mainly in the liver and visceral adipose tissue (VAT), and has been implicated in several metabolic disorders. The absence of systemic hypercortisolism in central obesity could be due to increased inactivation of cortisol to its tetrahydrometabolites by the hepatic enzymes 5α- and 5β-reductases. Our aim was to assess the expression of the reductases in the liver and of 11β-HSD1 in the liver and VAT in morbidly obese patients and to analyze their association with clinical, anthropometric, and biochemical parameters. Hepatic and VAT samples were obtained during bariatric surgery. 5α- and 5β-reductases, 11β-HSD1, and 18S expression was measured using real-time polymerase chain reaction. Anthropometric and biochemical variables were analyzed. Forty-one patients were recruited (age, 41.8 ± 10.6 years; body mass index, 42.1 ± 6.6 kg/m(2); 71% women). The expression of hepatic 5α- and 5β-reductases was positively correlated (r = +0.53, P = .004), and their expression levels were correlated with hepatic 11β-HSD1 expression (r = +0.61, P < .001 for 5α-reductase and r = +0.50, P < .001 for 5β-reductase). Hepatic 5α-reductase was associated with insulin (r = +0.34, P = .015). Visceral adipose tissue 11β-HSD1 expression was associated with glucose (r = +0.37, P = .025) and insulin (r = +0.54, P = .002). Our results showed that 5α-reductase and VAT 11β-HSD1 expressions were associated with insulinemia. These findings suggest that overexpression of 5α-reductase, through a higher inactivation of cortisol in the liver, could have a protective role in preserving hepatic sensitivity to insulin. The overexpression of liver reductases in obesity could be an adaptive response to an increase in cortisol production by the liver and visceral 11β-HSD1 to avoid systemic hypercortisolism.

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Gustavo Pérez

Pontifical Catholic University of Chile

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Camilo Boza

Pontifical Catholic University of Chile

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Fernando Pimentel

Pontifical Catholic University of Chile

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Fernando Crovari

Pontifical Catholic University of Chile

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Sergio Guzmán

Pontifical Catholic University of Chile

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Nicolas Devaud

Pontifical Catholic University of Chile

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Cristian Gamboa

Pontifical Catholic University of Chile

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Dannae Turiel

Pontifical Catholic University of Chile

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