Keith D. Gray

Systemic nf-κB activation in a transgenic mouse model of acute pancreatitis

Abstract Background. Transcription factor NF-κB has been implicated in numerous human inflammatory diseases. Acute pancreatitis can result in remote tissue injury, but the involved mechanisms are unknown. This study evaluates the role of systemic NF-κB activation in the pathogenesis of lung inflammation in a transgenic pancreatitis model. Materials and methods. Using transgenic mice expressing photinus luciferase controlled by an NF-κB-dependent promoter, luciferase activity was measured in pancreas, liver, and lung tissues as a surrogate marker of NF-κB activity. Luciferase activity was measured by in vivo bioluminescence and correlated to an in vitro luciferase assay of organ homogenates. Following measurement of luciferase activity in uninjured animals, these animals were fed a choline-deficient, ethionine supplemented diet for 48 h to induce pancreatitis, and luciferase activity was then measured at 48, 60, 72, and 96 h. Lung inflammation was determined by total nucleated cell counts in bronchoalveolar lavage (BAL) fluid. Results. Bioluminescence detected increased luciferase activity over the upper abdominal region at 48 and 60 h (P Conclusion. In this model, NF-κB binding activity is increased in the liver and lung. These data suggest that the liver modulates pancreatitis-induced systemic inflammatory response syndrome (SIRS) and suggest strategies to reduce multisystem injury.

Activation of nuclear factor kappa B and severe hepatic necrosis may mediate systemic inflammation in choline-deficient/ethionine-supplemented diet-induced pancreatitis

Objectives: We hypothesized that hepatic injury is associated with severe acute pancreatitis (SAP) and may result in lung injury through nuclear factor kappa B (NF-&kgr;B)-dependent inflammatory mediators. The study characterizes the timing and determines the involvement of selected cytokines and chemokines in the pathogenesis of hepatocellular injury associated with SAP. Methods: The SAP was induced in C57BL/6 mice by feeding a choline-deficient/ethionine-supplemented diet. The mice were killed at 12-hour intervals for 96 hours. Terminal deoxynucleotidyl transferase-mediated nick-end labeling staining was used to determine the extent of hepatic apoptosis. The NF-&kgr;B activation in nuclear protein extracts from liver tissue was measured using a sensitive RelA enzyme-linked immunoadsorbent assay. Tumor necrosis factor &agr;, interleukin 6, macrophage inflammatory protein (MIP) 2, and keratinocyte-derived chemokine (KC) levels in homogenates of liver and lung tissues were measured by enzyme-linked immunoadsorbent assay. The SAP-associated neutrophil lung inflammation was measured as tissue myeloperoxidase activity. Results: The SAP and subsequent liver injury were confirmed by histological analysis and rises in plasma amylase and transaminase levels. Severe hepatocellular apoptosis was detected at 36 and 48 hours after the diet initiation by terminal deoxynucleotidyl transferase-mediated nick-end labeling staining (P < 0.05) and subsequently progressed to hepatic necrosis. Liver NF-&kgr;B activation was detected at 36 hours (P < 0.05) and followed by a sharp increase in hepatocellular levels of interleukin 6, MIP-2, and KC at 72 hours and thereafter (P < 0.05). Levels of MIP-2 and KC in lung tissue were also elevated at 72 hours (P < 0.05) and closely correlated with increased myeloperoxidase activity and increased inflammatory cell infiltrate in the lung. Conclusions: Choline-deficient/ethionine-supplemented diet-induced SAP is accompanied with hepatocellular apoptosis and eventual necrosis. This injury is associated with the hepatic NF-&kgr;B activation leading to the production of NF-&kgr;B-dependent cytokines and chemokines in the liver, which may mediate the lung injury.

Primary Cutaneous Melanoma Arising in a Long-Standing Irradiated Keloid

Ionizing radiation has been used therapeutically for a variety of clinical conditions, including treatment of hypertrophic keloids. Keloids may rarely be associated with malignancy, but the use of low-dose ionizing radiation is associated with an increased risk of cutaneous malignancies. We describe a case in which a primary desmoplastic melanoma arose in a long-standing, previously irradiated keloid.

Contralateral Prophylactic Mastectomy: Characteristics Influencing Utilization

Purpose: Breast conservation has been shown to have similar mortality rates as compared to mastectomy. We hypothesized that variables involving the patient, tumor and surgeon influence the treatment a patient may choose. Methods: Retrospective review of a prospectively maintained database of all patients who underwent surgical treatment for breast cancer between 2000 and 2009 was performed. Multivariate logistic regression models were used to compare characteristics associated with breast conservation therapy (BCT) and contralateral prophylactic mastectomy (CPM). Results: Of 1826 patients, 806 underwent BCT and 207 underwent CPM. Exclusion criteria included unilateral mastectomy (n=761), bilateral disease, stage IV disease, and incomplete records. Larger average tumor size and number of lymph nodes examined were associated with CPM (both p<0.0001). There were higher odds of patients who underwent CPM when younger than 40 (OR=3.1), less than 50 years of age (OR=2.5), with a history of breast cancer (OR=4.7), lobular histology (OR=2.3), invasive histology (OR=2.1), and multi-centric (OR=8.2). Patients treated by surgeons with greater than 10 years of experience were less than half as likely to undergo CPM (OR=0.4), however when treated by a surgeon not subspecialty trained in surgical oncology the patient was more likely to undergo CPM (OR=3.4). Conclusions: Our study is one of the first to evaluate patient comorbidities, personal history of breast cancer, and length of surgeon experience and the influence each may have on usage of CPM. Our data also suggest that there may be a training gap to bridge for general surgeons, because more surgery is becoming subspecialized.