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Research paper thumbnail of Metformin Use Is Inversely Associated with Prevalent, but Not Incident Colorectal Adenomas

Digestive Diseases and Sciences

Chemoprevention for colorectal neoplasia has attracted growing interest, with multiple medication... more Chemoprevention for colorectal neoplasia has attracted growing interest, with multiple medications investigated. Metformin may decrease the overall incidence of cancer in patients with diabetes and may decrease the incidence of colorectal cancer. We aimed to determine the impact of metformin use on the behavior of colorectal adenomas in a US veteran population. All patients with at least two high-quality colonoscopies between January 1997 and December 2013 at Veterans Affairs New York Harbor Healthcare System were identified. Outpatient prescription records were used to determine metformin exposure, and colonoscopy findings were recorded. Multivariable logistic regression was used to determine factors associated with adenoma detection on baseline and interval colonoscopy. In total, 1869 patients with two successive colonoscopies (median 4.5 years) were included. Four hundred and sixty patients had metformin exposure prior to baseline and/or interval colonoscopy. Overall adenoma detection rate was 59.7% at baseline and 45.9% at interval colonoscopy. On multivariable analysis, metformin use was associated with decreased adenoma prevalence at baseline (OR 0.68; 95% CI 0.51–0.92; p = 0.015). Metformin did not impact adenoma incidence at interval colonoscopy whether prescribed before baseline (OR 1.26; 95% CI 0.60–2.67), after baseline (OR 1.25; 95% CI 0.91–1.72), or before and after baseline (OR 1.14; 95% CI 0.82–1.58). In this retrospective analysis of an average-risk cohort, metformin use was associated with a decreased prevalence of colorectal adenomas at baseline colonoscopy. This inverse association did not persist on interval colonoscopy. Prospective studies are needed to evaluate potential chemoprotective effects of metformin over time.

Research paper thumbnail of Comprehensive meta-analysis of randomized controlled trials of Lactated Ringer’s versus Normal Saline for acute pancreatitis

Pancreatology

INTRODUCTION Fluid resuscitation is the keystone of treatment for acute pancreatitis. Though clin... more INTRODUCTION Fluid resuscitation is the keystone of treatment for acute pancreatitis. Though clinical guidelines and expert opinions agree on large volume resuscitation, debate remains on the optimal fluid type. The most commonly used fluids are Lactated Ringer's (LR) and Normal Saline (NS), but the studies published to date comparing LR vs NS yield conflicting results. We aimed to identify and quantitatively synthesize existing high quality data of the topic of fluid type or acute pancreatitis resuscitation. METHODS In collaboration with the study team, an information specialist performed a comprehensive literature review to identify reports addressing type of fluid resuscitation. Studies were screened using the Covidence system by two independent reviewers in order to identify Randomized controlled trials comparing LR versus NS. The main outcome was the development of moderately severe or severe pancreatitis and additional outcomes included local complications, ICU admission, and length of stay. Pooled odds ratios were estimated using the random effects model and standardized mean difference to compare continuous variables. RESULTS We reviewed 7964 abstracts and 57 full text documents. Four randomized controlled trials were identified and included in our meta-analyses. There were a total of 122 patients resuscitated with LR versus 126 with NS. Patients resuscitated with LR were less likely to develop moderately severe/severe pancreatitis (OR 0.49; 95 % CI 0.25-0.97). There was no difference in development of SIRS at 24 or 48 h or development of organ failure between the two groups. Patients resuscitated with LR were less likely to require ICU admission (OR 0.33; 95 % CI 0.13-0.81) and local complications (OR 0.42; 95 % CI 0.2-0.88). While there was a trend towards shorter hospitalizations for LR (SMD -0.18, 99 % CI -0.44-0.07), it was not statistically significant. CONCLUSION Resuscitation with LR reduces the development of moderately severe-severe pancreatitis relative to NS. Nevertheless, no difference in SIRS development or organ failure underscores the need for further studies to verify this finding and define its mechanism.

Research paper thumbnail of ASGE guideline on the management of cholangitis

Gastrointestinal Endoscopy

Research paper thumbnail of Lactated Ringers vs Normal Saline Resuscitation for Mild Acute Pancreatitis: A Randomized Trial

Gastroenterology, 2021

The standard method to train the Higher Order Neural Networks (HONN) is the well-known Backpropag... more The standard method to train the Higher Order Neural Networks (HONN) is the well-known Backpropagation (BP) algorithm. Yet, the current BP algorithm has several limitations including easily stuck into local minima, particularly when dealing with highly non-linear problems and utilise computationally intensive training algorithms. The current BP algorithm is also relying heavily on the initial weight values and other parameters picked. Therefore, in an attempt to overcome the BP drawbacks, we investigate a method called Modified Cuckoo Search-Markov chain Monté Carlo for optimising the weights in HONN and boost the learning process. This method, which lies in the Swarm Intelligence area, is notably successful in optimisation task. We compared the performance with several HONN-based network models and standard Multilayer Perceptron on four (4) time series datasets: Temperature, Ozone, Gold Close Price and Bitcoin Closing Price from various repositories. Simulation results indicate that this swarm-based algorithm outperformed or at least at par with the network models with current BP algorithm in terms of lower error rate.

Research paper thumbnail of Fr311 LACTATED RINGER'S DECREASES MODERATELY SEVERE/SEVERE PANCREATITIS: COMPREHENSIVE META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS

Research paper thumbnail of S0091 Admission Outcomes and Risk Factors for Patients Presenting With Acute Pancreatitis and Concomitant Diabetic Ketoacidosis

American Journal of Gastroenterology, 2020

Research paper thumbnail of S0928 ERCP for Gallstone Pancreatitis in Fluid Sensitive Patients Is Associated With Increased Rates of Volume Overload Without Increased Rates of Post-ERCP Pancreatitis

American Journal of Gastroenterology, 2020

Research paper thumbnail of Su1250 – Feasibility of Gastric Intestinal Metaplasia Surveillance in a High Risk American Cohort

Research paper thumbnail of Su1558 A SYSTEMATIC REVIEW AND META-ANALYSIS OF ENDOSCOPIC VERSUS PERCUTANEOUS MANAGEMENT OF CHOLANGITIS

Gastrointestinal Endoscopy, 2020

Research paper thumbnail of Su1474 INFLUENCE OF PRE-EXISTING DIABETES MELLITUS ON ACUTE PANCREATITIS OUTCOMES

Research paper thumbnail of Sa1362 INCREASED FLUID RATE HASTENS RECOVERY OF ACUTE KIDNEY INJURY IN ACUTE PANCREATITIS

Research paper thumbnail of 835 Lactated Ringer's Solution Versus Normal Saline in the Management of Acute Pancreatitis: A Double-Blind Randomized Controlled Trial

Research paper thumbnail of Meta-Analysis and Systematic Review of Initial Endoscopic Therapy for Cholangitis

American Journal of Gastroenterology, 2019

Research paper thumbnail of Assessing the Impact of Metformin Use on Colonic Polyp Behavior

American Journal of Gastroenterology, 2018

Research paper thumbnail of Conversion of a surgically arthrodesed knee to a total knee arthroplasty - Is it worth it? A Systematic Review

The Journal of Arthroplasty, 2016

Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a s... more Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a select group of patients who are not satisfied with their results. However, there is a paucity of literature on this topic. A systematic review of literature was performed to (1) describe the overall demographic characteristics; (2) evaluate the clinical outcomes; (3) determine the overall rate of complications; and (4) evaluate the overall satisfaction of patients who underwent conversion of an arthrodesed knee to TKA. A comprehensive literature search was systematically performed to evaluate all studies included in the literature until July 2015. The specific search terms used were "fusion knee" and "arthrodesis knee," which revealed a total of 2206 studies. A review and selection of these abstracts were then performed based on inclusion and/or exclusion criteria; a total of 10 articles were used for final review. There were a total of 98 surgically arthrodesed knees that subsequently underwent TKA. Patients had a mean age of 55 years and were followed up for a mean of 5 years. Using a random effects model, there was an overall complication rate of 47%, an overall revision rate of 25%, and an overall failure rate of 11%. However, most patients were overall satisfied with the procedure. Fusion takedown is a challenging procedure that should only be performed by experienced surgeons after extensive discussion with the patients. The clinical outcomes are good with overall patient satisfaction, but complication rates are high including risk of repeat fusion or amputation.

Research paper thumbnail of Synthetic dendrimeric peptide active against biofilm and persister cells of Pseudomonas aeruginosa

Applied microbiology and biotechnology, Jan 27, 2015

Antimicrobial dendrimeric peptides (AMDP) are a relatively new class of agents displaying repetit... more Antimicrobial dendrimeric peptides (AMDP) are a relatively new class of agents displaying repetitive functional groups on a branched core. Previously, we have investigated the length requirement for antimicrobial activity of peptides consisting of repeated arginine (R) and tryptophan (W) side chains and found that even short linear RW repeats are active, providing a starting point for a de novo design of multivalent structures. In this study, we synthesized and tested a new synthetic dendrimer, 2D-24, for its antimicrobial activity against Pseudomonas aeruginosa, including the wild-type PAO1 and its mucoid mutant PDO300. This synthetic AMDP was found to kill planktonic cells of both PAO1 and PDO300 in a dose-dependent manner, with nearly complete killing of both strains observed when treated with 50 μM of this agent. In addition to planktonic cells, 2D-24 was also found to kill biofilm cells of both strains in a dose-dependent manner. For example, treatment with 30 μM 2D-24 led to 9...

Research paper thumbnail of Conversion of a surgically arthrodesed knee to a total knee arthroplasty - Is it worth it? A Systematic Review

The Journal of Arthroplasty, 2016

Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a s... more Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a select group of patients who are not satisfied with their results. However, there is a paucity of literature on this topic. A systematic review of literature was performed to (1) describe the overall demographic characteristics; (2) evaluate the clinical outcomes; (3) determine the overall rate of complications; and (4) evaluate the overall satisfaction of patients who underwent conversion of an arthrodesed knee to TKA. A comprehensive literature search was systematically performed to evaluate all studies included in the literature until July 2015. The specific search terms used were "fusion knee" and "arthrodesis knee," which revealed a total of 2206 studies. A review and selection of these abstracts were then performed based on inclusion and/or exclusion criteria; a total of 10 articles were used for final review. There were a total of 98 surgically arthrodesed knees that subsequently underwent TKA. Patients had a mean age of 55 years and were followed up for a mean of 5 years. Using a random effects model, there was an overall complication rate of 47%, an overall revision rate of 25%, and an overall failure rate of 11%. However, most patients were overall satisfied with the procedure. Fusion takedown is a challenging procedure that should only be performed by experienced surgeons after extensive discussion with the patients. The clinical outcomes are good with overall patient satisfaction, but complication rates are high including risk of repeat fusion or amputation.

Research paper thumbnail of Metformin Use Is Inversely Associated with Prevalent, but Not Incident Colorectal Adenomas

Digestive Diseases and Sciences

Chemoprevention for colorectal neoplasia has attracted growing interest, with multiple medication... more Chemoprevention for colorectal neoplasia has attracted growing interest, with multiple medications investigated. Metformin may decrease the overall incidence of cancer in patients with diabetes and may decrease the incidence of colorectal cancer. We aimed to determine the impact of metformin use on the behavior of colorectal adenomas in a US veteran population. All patients with at least two high-quality colonoscopies between January 1997 and December 2013 at Veterans Affairs New York Harbor Healthcare System were identified. Outpatient prescription records were used to determine metformin exposure, and colonoscopy findings were recorded. Multivariable logistic regression was used to determine factors associated with adenoma detection on baseline and interval colonoscopy. In total, 1869 patients with two successive colonoscopies (median 4.5 years) were included. Four hundred and sixty patients had metformin exposure prior to baseline and/or interval colonoscopy. Overall adenoma detection rate was 59.7% at baseline and 45.9% at interval colonoscopy. On multivariable analysis, metformin use was associated with decreased adenoma prevalence at baseline (OR 0.68; 95% CI 0.51–0.92; p = 0.015). Metformin did not impact adenoma incidence at interval colonoscopy whether prescribed before baseline (OR 1.26; 95% CI 0.60–2.67), after baseline (OR 1.25; 95% CI 0.91–1.72), or before and after baseline (OR 1.14; 95% CI 0.82–1.58). In this retrospective analysis of an average-risk cohort, metformin use was associated with a decreased prevalence of colorectal adenomas at baseline colonoscopy. This inverse association did not persist on interval colonoscopy. Prospective studies are needed to evaluate potential chemoprotective effects of metformin over time.

Research paper thumbnail of Comprehensive meta-analysis of randomized controlled trials of Lactated Ringer’s versus Normal Saline for acute pancreatitis

Pancreatology

INTRODUCTION Fluid resuscitation is the keystone of treatment for acute pancreatitis. Though clin... more INTRODUCTION Fluid resuscitation is the keystone of treatment for acute pancreatitis. Though clinical guidelines and expert opinions agree on large volume resuscitation, debate remains on the optimal fluid type. The most commonly used fluids are Lactated Ringer's (LR) and Normal Saline (NS), but the studies published to date comparing LR vs NS yield conflicting results. We aimed to identify and quantitatively synthesize existing high quality data of the topic of fluid type or acute pancreatitis resuscitation. METHODS In collaboration with the study team, an information specialist performed a comprehensive literature review to identify reports addressing type of fluid resuscitation. Studies were screened using the Covidence system by two independent reviewers in order to identify Randomized controlled trials comparing LR versus NS. The main outcome was the development of moderately severe or severe pancreatitis and additional outcomes included local complications, ICU admission, and length of stay. Pooled odds ratios were estimated using the random effects model and standardized mean difference to compare continuous variables. RESULTS We reviewed 7964 abstracts and 57 full text documents. Four randomized controlled trials were identified and included in our meta-analyses. There were a total of 122 patients resuscitated with LR versus 126 with NS. Patients resuscitated with LR were less likely to develop moderately severe/severe pancreatitis (OR 0.49; 95 % CI 0.25-0.97). There was no difference in development of SIRS at 24 or 48 h or development of organ failure between the two groups. Patients resuscitated with LR were less likely to require ICU admission (OR 0.33; 95 % CI 0.13-0.81) and local complications (OR 0.42; 95 % CI 0.2-0.88). While there was a trend towards shorter hospitalizations for LR (SMD -0.18, 99 % CI -0.44-0.07), it was not statistically significant. CONCLUSION Resuscitation with LR reduces the development of moderately severe-severe pancreatitis relative to NS. Nevertheless, no difference in SIRS development or organ failure underscores the need for further studies to verify this finding and define its mechanism.

Research paper thumbnail of ASGE guideline on the management of cholangitis

Gastrointestinal Endoscopy

Research paper thumbnail of Lactated Ringers vs Normal Saline Resuscitation for Mild Acute Pancreatitis: A Randomized Trial

Gastroenterology, 2021

The standard method to train the Higher Order Neural Networks (HONN) is the well-known Backpropag... more The standard method to train the Higher Order Neural Networks (HONN) is the well-known Backpropagation (BP) algorithm. Yet, the current BP algorithm has several limitations including easily stuck into local minima, particularly when dealing with highly non-linear problems and utilise computationally intensive training algorithms. The current BP algorithm is also relying heavily on the initial weight values and other parameters picked. Therefore, in an attempt to overcome the BP drawbacks, we investigate a method called Modified Cuckoo Search-Markov chain Monté Carlo for optimising the weights in HONN and boost the learning process. This method, which lies in the Swarm Intelligence area, is notably successful in optimisation task. We compared the performance with several HONN-based network models and standard Multilayer Perceptron on four (4) time series datasets: Temperature, Ozone, Gold Close Price and Bitcoin Closing Price from various repositories. Simulation results indicate that this swarm-based algorithm outperformed or at least at par with the network models with current BP algorithm in terms of lower error rate.

Research paper thumbnail of Fr311 LACTATED RINGER'S DECREASES MODERATELY SEVERE/SEVERE PANCREATITIS: COMPREHENSIVE META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS

Research paper thumbnail of S0091 Admission Outcomes and Risk Factors for Patients Presenting With Acute Pancreatitis and Concomitant Diabetic Ketoacidosis

American Journal of Gastroenterology, 2020

Research paper thumbnail of S0928 ERCP for Gallstone Pancreatitis in Fluid Sensitive Patients Is Associated With Increased Rates of Volume Overload Without Increased Rates of Post-ERCP Pancreatitis

American Journal of Gastroenterology, 2020

Research paper thumbnail of Su1250 – Feasibility of Gastric Intestinal Metaplasia Surveillance in a High Risk American Cohort

Research paper thumbnail of Su1558 A SYSTEMATIC REVIEW AND META-ANALYSIS OF ENDOSCOPIC VERSUS PERCUTANEOUS MANAGEMENT OF CHOLANGITIS

Gastrointestinal Endoscopy, 2020

Research paper thumbnail of Su1474 INFLUENCE OF PRE-EXISTING DIABETES MELLITUS ON ACUTE PANCREATITIS OUTCOMES

Research paper thumbnail of Sa1362 INCREASED FLUID RATE HASTENS RECOVERY OF ACUTE KIDNEY INJURY IN ACUTE PANCREATITIS

Research paper thumbnail of 835 Lactated Ringer's Solution Versus Normal Saline in the Management of Acute Pancreatitis: A Double-Blind Randomized Controlled Trial

Research paper thumbnail of Meta-Analysis and Systematic Review of Initial Endoscopic Therapy for Cholangitis

American Journal of Gastroenterology, 2019

Research paper thumbnail of Assessing the Impact of Metformin Use on Colonic Polyp Behavior

American Journal of Gastroenterology, 2018

Research paper thumbnail of Conversion of a surgically arthrodesed knee to a total knee arthroplasty - Is it worth it? A Systematic Review

The Journal of Arthroplasty, 2016

Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a s... more Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a select group of patients who are not satisfied with their results. However, there is a paucity of literature on this topic. A systematic review of literature was performed to (1) describe the overall demographic characteristics; (2) evaluate the clinical outcomes; (3) determine the overall rate of complications; and (4) evaluate the overall satisfaction of patients who underwent conversion of an arthrodesed knee to TKA. A comprehensive literature search was systematically performed to evaluate all studies included in the literature until July 2015. The specific search terms used were "fusion knee" and "arthrodesis knee," which revealed a total of 2206 studies. A review and selection of these abstracts were then performed based on inclusion and/or exclusion criteria; a total of 10 articles were used for final review. There were a total of 98 surgically arthrodesed knees that subsequently underwent TKA. Patients had a mean age of 55 years and were followed up for a mean of 5 years. Using a random effects model, there was an overall complication rate of 47%, an overall revision rate of 25%, and an overall failure rate of 11%. However, most patients were overall satisfied with the procedure. Fusion takedown is a challenging procedure that should only be performed by experienced surgeons after extensive discussion with the patients. The clinical outcomes are good with overall patient satisfaction, but complication rates are high including risk of repeat fusion or amputation.

Research paper thumbnail of Synthetic dendrimeric peptide active against biofilm and persister cells of Pseudomonas aeruginosa

Applied microbiology and biotechnology, Jan 27, 2015

Antimicrobial dendrimeric peptides (AMDP) are a relatively new class of agents displaying repetit... more Antimicrobial dendrimeric peptides (AMDP) are a relatively new class of agents displaying repetitive functional groups on a branched core. Previously, we have investigated the length requirement for antimicrobial activity of peptides consisting of repeated arginine (R) and tryptophan (W) side chains and found that even short linear RW repeats are active, providing a starting point for a de novo design of multivalent structures. In this study, we synthesized and tested a new synthetic dendrimer, 2D-24, for its antimicrobial activity against Pseudomonas aeruginosa, including the wild-type PAO1 and its mucoid mutant PDO300. This synthetic AMDP was found to kill planktonic cells of both PAO1 and PDO300 in a dose-dependent manner, with nearly complete killing of both strains observed when treated with 50 μM of this agent. In addition to planktonic cells, 2D-24 was also found to kill biofilm cells of both strains in a dose-dependent manner. For example, treatment with 30 μM 2D-24 led to 9...

Research paper thumbnail of Conversion of a surgically arthrodesed knee to a total knee arthroplasty - Is it worth it? A Systematic Review

The Journal of Arthroplasty, 2016

Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a s... more Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a select group of patients who are not satisfied with their results. However, there is a paucity of literature on this topic. A systematic review of literature was performed to (1) describe the overall demographic characteristics; (2) evaluate the clinical outcomes; (3) determine the overall rate of complications; and (4) evaluate the overall satisfaction of patients who underwent conversion of an arthrodesed knee to TKA. A comprehensive literature search was systematically performed to evaluate all studies included in the literature until July 2015. The specific search terms used were "fusion knee" and "arthrodesis knee," which revealed a total of 2206 studies. A review and selection of these abstracts were then performed based on inclusion and/or exclusion criteria; a total of 10 articles were used for final review. There were a total of 98 surgically arthrodesed knees that subsequently underwent TKA. Patients had a mean age of 55 years and were followed up for a mean of 5 years. Using a random effects model, there was an overall complication rate of 47%, an overall revision rate of 25%, and an overall failure rate of 11%. However, most patients were overall satisfied with the procedure. Fusion takedown is a challenging procedure that should only be performed by experienced surgeons after extensive discussion with the patients. The clinical outcomes are good with overall patient satisfaction, but complication rates are high including risk of repeat fusion or amputation.