Establishment of genetically diverse patient-derived xenografts of colorectal cancer.

Preclinical compounds tested in animal models often show limited efficacy when transitioned into human clinical trials. As a result, many patients are stratified into treatment regimens that have little impact on their disease. In order to create preclinical models that can more accurately predict tumor responses, we established patient-derived xenograft (PDX) models of colorectal cancer (CRC).

Minimally invasive colorectal resection for benign pathology is associated with persistent proangiogenic plasma compositional changes.

Background: Minimally invasive colorectal resection for cancer is associated with increased plasma levels of numerous proangiogenic proteins for 3 to 4 weeks postoperatively, and plasma from postoperative weeks 2 and 3 stimulates proangiogenic endothelial cell behavior in vitro. It is unknown if similar plasma changes occur after minimally invasive colorectal resection for benign pathology.

Objective: The aim of this study is to assess 1) plasma levels of angiopoetin-2, placental growth factor, and soluble vascular cell adhesion molecule-1 after minimally invasive colorectal resection for benign pathology and 2) postoperative plasma's effects on in vitro endothelial cell proliferation (branch point formation), migration, and invasion.

Bioabsorbable staple line reinforcement in restorative proctectomy and anterior resection: a randomized study.

Background: Anastomotic complications, including leaks, strictures/stenoses, and bleeding, cause considerable mortality and morbidity after colorectal surgery.

Objective: The aim of this study was to assess whether the use of a synthetic, bioabsorbable staple line reinforcement material with circular staplers would reduce postoperative anastomotic leakage in patients with a colorectal, coloanal, or ileoanal anastomosis.

Design: This was a randomized study that compared outcomes in patients in whom the reinforcement material was used with those in patients who were not given the material.

Anastomotic leaks: technique and timing of detection.

Background: Despite the proven benefits of laparoscopic colorectal surgery, the rate of anastomotic leaks has not changed. This study looks at the time of presentation of anastomotic leaks between laparoscopic and open colectomies.

Methods: Retrospective chart review was performed between July 2008 and 2012.

Outcomes of ileocolic resection and right hemicolectomies for Crohn's patients in comparison with non-Crohn's patients and the impact of perioperative immunosuppressive therapy with biologics and steroids on inpatient complications.

Background: The purpose of this study was to compare medication use and complication rates between Crohn's disease (CD) and non-CD patients undergoing ileocolic resections and right hemicolectomies.

Methods: A review of patients who underwent ileocolic resections and right hemicolectomies from January 1, 2003, through December 31, 2010, was performed. Data collected included demographics and clinical information, biologics use (eg, infliximab, adalimumab), other medication use (eg, steroids), complications, and mortality.

Plasma from the second and third weeks after open colorectal resection for cancer stimulates in vitro endothelial cell growth, migration, and invasion.

Introduction: Angiogenesis is central to wound healing and tumor growth. Postoperative (postop) plasma from weeks 2 and 3 after minimally invasive colorectal resection (MICR) stimulates endothelial cell (EC) migration (MIG), invasion (INV), and proliferation (all vital to angiogenesis) compared with preoperative (preop) plasma results and may promote postop tumor growth. The purpose of this study was to determine whether plasma from open colorectal resection (OCR) patients has similar proangiogenic EC effects in vitro.

Citrulline: a potential immunomodulator in sepsis.

Background: Sepsis leads to a complex systemic response of cytokines (both pro- and anti-inflammatory) and more recently recognized adipokine mediators. Endothelial nitric oxide (NO) may be a key component in regulating this response, but the pharmacologic manipulation of endothelial NO via L-arginine supplementation or inhibitors has provided inconsistent clinical data related to outcomes. These failures are related to the metabolism of L-arginine in the liver, toxicity of L-arginine, and asymmetric dimethylarginine inhibition, all of which may explain the "arginine paradox.

Serum adiponectin, resistin, and circulating soluble receptor for advanced glycation end products in colectomy patients.

Aim: Surgical trauma and associated complications are frequently related to physiological stress during colectomy. This study evaluated the response of adiponectin, resistin, and circulating soluble receptor for advanced glycation end products (sRAGE) in colectomy patients with or without an enhanced recovery protocol.

Method: Serum samples were collected from 44 colectomy patients at 3 timframes.

Minimally invasive colorectal resection is associated with a rapid and sustained decrease in plasma levels of epidermal growth factor (EGF) in the colon cancer setting.

Background: Epidermal growth factor (EGF) stimulates tumor growth directly via tumor cell EGF receptors or indirectly via its proangiogenic effects. This study's purpose was to determine the impact of minimally invasive colorectal resection (MICR) on postoperative (postop) plasma EGF levels in the colorectal cancer (CRC) and benign disease settings and to see if preoperative (PreOp) EGF levels are altered in cancer patients.

Methods: MICR patients with benign pathology (n = 40) and CRC (n = 48) had blood samples taken PreOp and on postoperative days (POD) 1 and 3.

Colorectal resection is associated with persistent proangiogenic plasma protein changes: postoperative plasma stimulates in vitro endothelial cell growth, migration, and invasion.

Introduction: Plasma vascular endothelial growth factor (VEGF) levels are elevated for weeks after minimally invasive colorectal resection (MICR). Decreased plasma angiopoietin-(Ang) 1 and increased Ang-2 levels have been noted on postoperative days (POD) 1 and 3. These proangiogenic changes may stimulate tumor growth postoperatively (postop).

Preoperative considerations and creation of normal ostomies.

Stomas provide fecal diversion in emergent and elective settings. Preoperative planning and counseling are extremely important to the creation of an acceptable and functional ostomy for the surgeon and patient. Proper site selection will help decrease the incidence of postoperative complications.

Laparoscopic vs. hand-assisted laparoscopic sigmoidectomy for diverticulitis.

Introduction: Sigmoid colectomy for diverticulitis can be technically challenging because of severe inflammation in the left-lower quadrant and pelvis. We hypothesized that hand-assisted laparoscopic technique may facilitate laparoscopic completion of this surgery while retaining the short-term benefits associated with "pure" laparoscopic surgery, in which an incision is made only for extracting the specimen. This study was designed to compare the outcomes of patients who underwent totally laparoscopic or hand-assisted laparoscopic sigmoidectomy for diverticulitis.

Effects of a laparoscopic course on student interest in surgical residency.

Background: The number of surgical residency applicants has been declining. Early introduction of the discipline of surgery is thought to stimulate early interest in surgical residency. This study investigated the hypothesis that a laparoscopic skills course introduced in preclinical years would stimulate student interest in entering surgical residency.

Anorectal anatomy and embryology.

The anal canal is complex in its anatomy and its embryologic origin. The intricate and changing histology of the anal canal explains the different types of anal cancer. In addition, an understanding of the venous and the lymphatic drainage of the anal canal helps to explain its methods of dissemination.

IFN-gamma production is specifically regulated by IL-10 in mice made tolerant with anti-CD40 ligand antibody and intact active bone.

We have developed a strategy to induce tolerance to allografts, involving cotransplantation of allogeneic intact active bone and transient anti-CD40 ligand mAb therapy. Tolerance induced by this approach in C57BL/6 mice receiving BALB/c hearts is not mediated by deletional mechanisms, but by peripheral regulatory mechanisms. Tolerance is associated with diminished ex vivo IFN-gamma production that is donor specific, and a reduction in the frequency of IFN-gamma-producing cells.

Acute xenograft rejection mediated by antibodies produced independently of TH1/TH2 cytokine profiles.

There is substantial support for the hypothesis that T(H)1 cytokine responses are critical for the normal elaboration of allograft rejection. Recent studies by Wang et al. (1) underscore the importance of T(H)2 responses in xenograft rejection and revealed that T(H)1 cytokines, IL-12 and interferon-gamma (IFN-gamma), can negatively regulate the development of humoral responses necessary for xenograft rejection.

A pilot study comparing percutaneous decompression with decompressive laparotomy for acute abdominal compartment syndrome in thermal injury.

Abdominal Compartment Syndrome (ACS) has multiple causes, and decompressive laparotomy has been the most frequent modality to prevent worsening cardiovascular, respiratory, and renal function. This pilot study evaluated the utility of percutaneous drainage (PD) of peritoneal fluid compared with decompressive laparotomy in burn patients. A 26-month review was conducted.