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Dive into the research topics where Jennifer N. Choi is active.

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Featured researches published by Jennifer N. Choi.


Hpb Surgery | 2009

Pancreatic Fistula Following Pancreaticoduodenectomy: Clinical Predictors and Patient Outcomes

C. Max Schmidt; Jennifer N. Choi; Emilie S. Powell; Constantin T. Yiannoutsos; Nicholas J. Zyromski; Attila Nakeeb; Henry A. Pitt; Eric A. Wiebke; James A. Madura; Keith D. Lillemoe

Pancreatic fistula continues to be a common complication following PD. This study seeks to identify clinical factors which may predict pancreatic fistula (PF) and evaluate the effect of PF on outcomes following pancreaticoduodenectomy (PD). We performed a retrospective analysis of a clinical database at an academic tertiary care hospital with a high volume of pancreatic surgery. Five hundred ten consecutive patients underwent PD, and PF occurred in 46 patients (9%). Perioperative mortality of patients with PF was 0%. Forty-five of 46 PF (98%) closed without reoperation with a mean time to closure of 34 days. Patients who developed PF showed a higher incidence of wound infection, intra-abdominal abscess, need for reoperation, and hospital length of stay. Multivariate analysis demonstrated an invaginated pancreatic anastomosis and closed suction intraperitoneal drainage were associated with PF whereas a diagnosis of chronic pancreatitis and endoscopic stenting conferred protection. Development of PF following PD in this series was predicted by gender, preoperative stenting, pancreatic anastomotic technique, and pancreas pathology. Outcomes in patients with PF are remarkable for a higher rate of septic complications, longer hospital stays, but in this study, no increased mortality.


Journal of Surgical Research | 2008

The effect of doxorubicin on MEK-ERK signaling predicts its efficacy in HCC.

Jennifer N. Choi; Michele T. Yip-Schneider; Faith Albertin; Chad A. Wiesenauer; Yufang Wang; C. Max Schmidt

BACKGROUND Hepatocellular cancer (HCC) is a leading cause of cancer-related death worldwide. Historically, doxorubicin (DOX) has been widely used against unresectable HCC with variable response rates. MATERIALS AND METHODS We hypothesized that DOX combined with mitogen-activated protein kinase kinase-extracellular signal-regulated kinase (MEK-ERK) targeted therapy may provide enhanced anti-cancer effects. Human HCC cell lines (HepG2, Hep3B) were treated with DOX and MEK enzyme inhibitors, U0126 or PD184161, alone or in combination. Growth, apoptosis, and ERK expression/MEK activity were respectively determined by proliferation assay, DNA fragmentation enzyme-linked immunoassay or fluorochrome inhibitor of caspases, and Western blot. RESULTS DOX (0.01-1 microM) decreased cell proliferation in Hep3B cells (IC(50) approximately 0.12 microM) at 48 to 72 h; DOX was less effective in HepG2 cells (IC(50) approximately 0.25 microM). At early time points (30 min) after DOX treatment of Hep3B cells, MEK activity was unchanged at low doses and decreased at higher doses; after 24 h, phospho-ERK levels increased at higher doses. Contrarily, in HepG2 cells, DOX caused a sustained, dose-dependent increase in phospho-ERK levels at early and late time points. The MEK inhibitor U0126 decreased phospho-ERK in both HCC lines. In contrast to DOX, HepG2 cells were more sensitive than Hep3B cells to U0126. The combination of DOX with U0126 (or PD184161) resulted in greater inhibition of proliferation in HepG2 but not in Hep3B cells. This effect may be mediated in part by enhanced apoptosis. CONCLUSIONS The effect of DOX on early and late induction of MEK activity predicts its chemotherapeutic response in HCC. Furthermore, this effect may also determine the utility of MEK inhibitor combination treatment.


Journal of Surgical Education | 2016

The Feasibility of Real-Time Intraoperative Performance Assessment With SIMPL (System for Improving and Measuring Procedural Learning): Early Experience From a Multi-institutional Trial

Jordan D. Bohnen; Brian C. George; Reed G. Williams; Mary C. Schuller; Debra A. DaRosa; Laura Torbeck; John T. Mullen; Shari L. Meyerson; Edward D. Auyang; Jeffrey G. Chipman; Jennifer N. Choi; Michael A. Choti; Eric D. Endean; Eugene F. Foley; Samuel P. Mandell; Andreas H. Meier; Douglas S. Smink; Kyla P. Terhune; Paul E. Wise; Nathaniel J. Soper; Joseph B. Zwischenberger; Keith D. Lillemoe; Gary L. Dunnington; Jonathan P. Fryer

PURPOSE Intraoperative performance assessment of residents is of growing interest to trainees, faculty, and accreditors. Current approaches to collect such assessments are limited by low participation rates and long delays between procedure and evaluation. We deployed an innovative, smartphone-based tool, SIMPL (System for Improving and Measuring Procedural Learning), to make real-time intraoperative performance assessment feasible for every case in which surgical trainees participate, and hypothesized that SIMPL could be feasibly integrated into surgical training programs. METHODS Between September 1, 2015 and February 29, 2016, 15 U.S. general surgery residency programs were enrolled in an institutional review board-approved trial. SIMPL was made available after 70% of faculty and residents completed a 1-hour training session. Descriptive and univariate statistics analyzed multiple dimensions of feasibility, including training rates, volume of assessments, response rates/times, and dictation rates. The 20 most active residents and attendings were evaluated in greater detail. RESULTS A total of 90% of eligible users (1267/1412) completed training. Further, 13/15 programs began using SIMPL. Totally, 6024 assessments were completed by 254 categorical general surgery residents (n = 3555 assessments) and 259 attendings (n = 2469 assessments), and 3762 unique operations were assessed. There was significant heterogeneity in participation within and between programs. Mean percentage (range) of users who completed ≥1, 5, and 20 assessments were 62% (21%-96%), 34% (5%-75%), and 10% (0%-32%) across all programs, and 96%, 75%, and 32% in the most active program. Overall, response rate was 70%, dictation rate was 24%, and mean response time was 12 hours. Assessments increased from 357 (September 2015) to 1146 (February 2016). The 20 most active residents each received mean 46 assessments by 10 attendings for 20 different procedures. CONCLUSIONS SIMPL can be feasibly integrated into surgical training programs to enhance the frequency and timeliness of intraoperative performance assessment. We believe SIMPL could help facilitate a national competency-based surgical training system, although local and systemic challenges still need to be addressed.


Surgery | 2014

How much guidance is given in the operating room? Factors influencing faculty self-reports, resident perceptions, and faculty/resident agreement

Laura Torbeck; Reed G. Williams; Jennifer N. Choi; Connie C. Schmitz; Jeffrey G. Chipman; Gary L. Dunnington

BACKGROUND Guidance in the operating room impacts resident confidence and ability to function independently. The purpose of this study was to explore attending surgeon guidance practices in the operating room as reported by faculty members themselves and by junior and senior residents. METHODS This was an exploratory, cross-sectional survey research study involving 91 categorical residents and 82 clinical faculty members at two academic general surgery training programs. A series of analyses of variance along with descriptive statistics were performed to understand the impact of resident training year, program, and surgeon characteristics (sex and type of surgery performed routinely) on guidance practices. RESULTS Resident level (junior versus senior) significantly impacted the amount of guidance given as reported by faculty and as perceived by residents. Within each program, junior residents perceived less guidance than faculty reported giving. For senior guidance practices, however, the differences between faculty and resident practices varied by program. In terms of the effects of surgeon practice type (mostly general versus mostly complex cases), residents at both institutions felt they were more supervised closely by the faculty who perform mostly complex cases. CONCLUSION More autonomy is given to senior than to junior residents. Additionally, faculty report a greater amount of change in their guidance practices over the training period than residents perceive. Faculty and resident agreement about the need for guidance and for autonomy are important for achieving the goals of residency training.


Surgery for Obesity and Related Diseases | 2014

Revisional bariatric surgery is more effective for improving obesity-related co-morbidities than it is for reinducing major weight loss.

Daniel T. McKenna; Don J. Selzer; Michael A. Burchett; Jennifer N. Choi; Samer G. Mattar

BACKGROUND Patients having previous bariatric surgery are at risk for weight regain and return of co-morbidities. If an anatomic basis for the failure is identified, many surgeons advocate revision or conversion to a Roux-en-Y gastric bypass. The aim of this study was to determine whether revisional bariatric surgery leads to sufficient weight loss and co-morbidity remission. PATIENTS AND METHODS From 2005-2012, patients undergoing revision were entered into a prospectively maintained database. Perioperative outcomes, including complications, weight loss, and co-morbidity remission, were examined for all patients with a history of a previous vertical banded gastroplasty (VBG) or Roux-en-Y gastric bypass (RYGB). RESULTS Twenty-two patients with a history of RYGB and 56 with a history of VBG were identified. Following the revisional procedure, the RYGB group experienced 35.8% excess weight loss (%EWL) and a 31.8% morbidity rate. For the VBG group, patients experienced a 46.2% %EWL from their weight before the revisional operation with a 51.8% morbidity rate. Co-morbidity remission rate was excellent. Diabetes (VBG:100%, RYGB: 85.7%), gastroesophageal reflux disease (VBG: 94.4%, RYGB: 80%), and hypertension (VBG: 74.2%, RYGB:60%) demonstrated significant improvement. CONCLUSION Revision of a failed RYGB or conversion of a VBG to a RYGB provides less weight loss and a higher complication rate than primary RYGB but provides an excellent opportunity for co-morbidity remission.


Annals of Surgery | 2017

Readiness of US General Surgery Residents for Independent Practice

Brian C. George; Jordan D. Bohnen; Reed G. Williams; Shari L. Meyerson; Mary C. Schuller; Michael Clark; Andreas H. Meier; Laura Torbeck; Samuel P. Mandell; John T. Mullen; Douglas S. Smink; Rebecca E. Scully; Jeffrey G. Chipman; Edward D. Auyang; Kyla P. Terhune; Paul E. Wise; Jennifer N. Choi; Eugene F. Foley; Justin B. Dimick; Michael A. Choti; Nathaniel J. Soper; Keith D. Lillemoe; Joseph B. Zwischenberger; Gary L. Dunnington; Debra A. DaRosa; Jonathan P. Fryer

Objective: This study evaluates the current state of the General Surgery (GS) residency training model by investigating resident operative performance and autonomy. Background: The American Board of Surgery has designated 132 procedures as being “Core” to the practice of GS. GS residents are expected to be able to safely and independently perform those procedures by the time they graduate. There is growing concern that not all residents achieve that standard. Lack of operative autonomy may play a role. Methods: Attendings in 14 General Surgery programs were trained to use a) the 5-level System for Improving and Measuring Procedural Learning (SIMPL) Performance scale to assess resident readiness for independent practice and b) the 4-level Zwisch scale to assess the level of guidance (ie, autonomy) they provided to residents during specific procedures. Ratings were collected immediately after cases that involved a categorical GS resident. Data were analyzed using descriptive statistics and supplemented with Bayesian ordinal model-based estimation. Results: A total of 444 attending surgeons rated 536 categorical residents after 10,130 procedures. Performance: from the first to the last year of training, the proportion of Performance ratings for Core procedures (n = 6931) at “Practice Ready” or above increased from 12.3% to 77.1%. The predicted probability that a typical trainee would be rated as Competent after performing an average Core procedure on an average complexity patient during the last week of residency training is 90.5% (95% CI: 85.7%–94%). This falls to 84.6% for more complex patients and to less than 80% for more difficult Core procedures. Autonomy: for all procedures, the proportion of Zwisch ratings indicating meaningful autonomy (“Passive Help” or “Supervision Only”) increased from 15.1% to 65.7% from the first to the last year of training. For the Core procedures performed by residents in their final 6 months of training (cholecystectomy, inguinal/femoral hernia repair, appendectomy, ventral hernia repair, and partial colectomy), the proportion of Zwisch ratings (n = 357) indicating near-independence (“Supervision Only”) was 33.3%. Conclusions: US General Surgery residents are not universally ready to independently perform Core procedures by the time they complete residency training. Progressive resident autonomy is also limited. It is unknown if the amount of autonomy residents do achieve is sufficient to ensure readiness for the entire spectrum of independent practice.


Journal of Surgical Research | 2009

Ethanol-TGFα-MEK Signaling Promotes Growth of Human Hepatocellular Carcinoma

Matthew Hennig; Michele T. Yip-Schneider; Patrick J. Klein; Sabrina C. Wentz; Jesus M. Matos; Courtney J. Doyle; Jennifer N. Choi; Huangbing Wu; Amanda O'Mara; Alex Menze; Stephen Noble; Iain H. McKillop; C. Max Schmidt

BACKGROUND Chronic ethanol intake is a significant risk factor for the development of cirrhosis and hepatocellular carcinoma (HCC). The effects of ethanol on extracellular signal-regulated kinase (ERK) activation, transforming growth factor alpha (TGF-alpha), and HCC growth were examined in this study. METHODS HepG2, SKHep, Hep3B human HCC cells, or normal human hepatocytes were treated with ethanol (0-100 mM), exogenous TGF-alpha, TGF-alpha neutralization antibody or the MEK inhibitor U0126. TGF-alpha levels were quantified by ELISA. Growth was determined by trypan blue-excluded cell counts. Cell cycle phase distribution was determined by flow cytometry. Protein expression was determined by Western blot. RESULTS Ethanol treatment (10-40 mM) increased ERK activation in HepG2 and SKHep HCC cells but not in Hep3B or human hepatocyte cells. Growth increased in HepG2 (174 +/- 29%, P < 0.05) and SKHep (149 +/- 12%, P < 0.05) cells in response to ethanol treatment. Correspondingly, ethanol increased S phase distribution in these cells. U0126 suppressed ethanol-induced growth increases. Ethanol treatment for 24 h also raised TGF-alpha levels in HepG2 cells (118%-198%) and SKHep cells (112%-177%). Exogenous administration of recombinant TGF-alpha mimicked the ethanol-induced growth in HepG2 and SKHep cells; TGF-alpha neutralization antibody effectively abrogated this effect. The TGF-a neutralization antibody also prevented ERK activation by ethanol in HepG2 cells. CONCLUSIONS These data demonstrate that clinically relevant doses of ethanol stimulate ERK-dependent proliferation of HCC cells. Ethanol up-regulates TGF-alpha levels in HCC cells and enhances growth through cell cycles changes, which appear to be mediated through TGF-alpha-MEK-ERK signaling. Ethanol-MEK signaling in normal hepatocytes is absent, suggesting that ethanol promotion of HCC growth may in part depend upon the acquisition of cancer-specific signaling by hepatocytes.


Neurogastroenterology and Motility | 2018

Idiopathic gastroparesis is associated with specific transcriptional changes in the gastric muscularis externa

Brian Paul Herring; April M. Hoggatt; A. Gupta; S. Griffith; Attila Nakeeb; Jennifer N. Choi; M. T. Idrees; Thomas V. Nowak; D. L. Morris; John M. Wo

The molecular changes that occur in the stomach that are associated with idiopathic gastroparesis are poorly described. The aim of this study was to use quantitative analysis of mRNA expression to identify changes in mRNAs encoding proteins required for the normal motility functions of the stomach.


American Journal of Surgery | 2017

Impact of integrated programs on general surgery operative volume

Amanda R. Jensen; Brianne Leigh Nickel; Scott C. Dolejs; David F. Canal; Laura Torbeck; Jennifer N. Choi

BACKGROUND Integrated residencies are now commonplace, co-existing with categorical general surgery residencies. The purpose of this study was to define the impact of integrated programs on categorical general surgery operative volume. METHODS Case logs from categorical general, integrated plastics, vascular, and thoracic surgery residents from a single institution from 2008 to 2016 were collected and analyzed. RESULTS Integrated residents have increased the number of cases they perform that would have previously been general surgery resident cases from 11 in 2009-2010 to 1392 in 2015-2016. Despite this, there was no detrimental effect on total major cases of graduating chief residents. CONCLUSIONS Multiple integrated programs can co-exist with a general surgery program through careful collaboration and thoughtful consideration to longitudinal needs of individual trainees. As additional programs continue to be created, both integrated and categorical program directors must continue to collaborate to insure the integrity of training for all residents.


Journal of Surgical Education | 2018

Identifying Managerial Roles of General Surgery Coordinators: Making the Case for Utilization of a Standardized Job Description Framework

Brianne Leigh Nickel; Jessica Roof; Scott C. Dolejs; Jennifer N. Choi; Laura Torbeck

OBJECTIVE Residency coordinators are valuable members of the education leadership administration. In General Surgery, program directors must devote time to both their clinical practice and as the leader of the education program for surgical residents. With the introduction of competencies and the Next Accreditation System, the responsibilities of training programs have increased, with much of the necessary day to day management being driven by the residency coordinator. The purpose of this study was to identify the current roles of a residency coordinator in surgery to determine appropriate language for a standardized job description that accurately describes the responsibilities of a program coordinator. DESIGN AND PARTICIPANTS A survey was created and distributed via email to 317 general surgery program coordinators in programs with continued, initial, or pre-accreditation status by the ACGME in October-December 2017. Questions were asked about coordinator demographics, ADS involvement, and communication with program director, recruitment, and professional development. 223 coordinators (70%) completed the survey. RESULTS Thirty-five percent of coordinators reported that their program director expects them to complete the annual ADS update in its entirety with a final review by the program director before submission, whereas 15% stated that the program director expects the program coordinator to input, update, and submit the annual ADS update without oversite from the program director. Fifty percent of program coordinators speak with their program director 2 to 4 days a week, whereas 38% speak with their program director daily. Eighty-nine percent of coordinators reported that their program directors trust them to make appropriate administrative decisions during scheduled or emergent absences. Sixty-nine percent of coordinators strongly agreed that they assist their program directors with collating and analyzing recruitment data post-recruitment season. Eighty-six percent of coordinators regularly participate in one or more professional development activities. Forty-six percent of coordinators stated that they oversee administrative staff in their office, division, or department. CONCLUSION Given the current makeup of todays residency coordinator in general surgery programs, the need for baseline qualifications and a standardized job description allowing for recruitment and retention of a coordinator capable of managing a residency along with a program director. The data from our survey indicate that most coordinators currently perform tasks and take on responsibilities of a manager, but they hold current job descriptions that do not adequately reflect the role. The current proposed ACGME revisions state that there must be a program coordinator for a residency program, citing the coordinator as an integral member of the residency leadership team. Therefore, human resource departments need a job description that identifies level of responsibility, contribution, leadership, and management required of a program coordinator.

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Reed G. Williams

Southern Illinois University School of Medicine

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Andreas H. Meier

State University of New York Upstate Medical University

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