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Paraconduit hiatal hernia (PCHH) is a known complication of esophagectomy with significant morbidity. PCHH may be more common with the transition to a minimally invasive approach and improved survival. We studied the PCHH occurrence following minimally invasive esophagectomy to determine the incidence, treatment, and associated risk factors.We retrospectively reviewed records of patients who underwent esophagectomy at an academic tertiary care center between 2013-2020. We divided the cohort into those who did and did not develop PCHH, identifying differences in demographics, perioperative characteristics and outcomes. We present video of our laparoscopic repair with mesh.Of 49 patients who underwent esophagectomy, seven (14%) developed PCHH at a median of 186 d (60-350 d) postoperatively. They were younger (57 versus 64 y, P0.01), and in cases of resection for cancer, more likely to develop tumor recurrence (71% versus 23%, P= 0.02). There was a significant difference in 2-y cancer free survival of patients with a PCHH (PCHH 19% versus no hernia 73%, P0.01), but no significant difference in 5-y overall survival (PCHH 36% versus no hernia 68%, P= 0.18). Five of seven PCHH were symptomatic and addressed surgically. Four PCHH repairs recurred at a median of 409 d.PCHH is associated with younger age and tumor recurrence, but not mortality. Safe repair of PCHH can be performed laparoscopically with or without mesh. Further studies, including systematic video review, are needed to address modifiable risk factors and identify optimal techniques for durable repair of post-esophagectomy PCHH.

Obesity promotes insulin resistance associated with liver inflammation, elevated glucose production, and type 2 diabetes. Although insulin resistance is attenuated in genetic mouse models that suppress systemic inflammation, it is not clear whether local resident macrophages in liver, denoted Kupffer cells (KCs), directly contribute to this syndrome. We addressed this question by selectively silencing the expression of the master regulator of inflammation, NF-κB, in KCs in obese mice. We used glucan-encapsulated small interfering RNA particles (GeRPs) that selectively silence gene expression in macrophages in vivo. Following intravenous injections, GeRPs containing siRNA against p65 of the NF-κB complex caused loss of NF-κB p65 expression in KCs without disrupting NF-κB in hepatocytes or macrophages in other tissues. Silencing of NF-κB expression in KCs in obese mice decreased cytokine secretion and improved insulin sensitivity and glucose tolerance without affecting hepatic lipid accumulation. Importantly, GeRPs had no detectable toxic effect. Thus, KCs are key contributors to hepatic insulin resistance in obesity and a potential therapeutic target for metabolic disease.—Tencerova, M., Aouadi, M., Vangala, P., Nicoloro, S. M., Yawe, J. C., Cohen, J. L., Shen, Y., Garcia-Menendez, L., Pedersen, D. J., Gallagher-Dorval, K., Perugini, R. A., Gupta, O. T., Czech, M. P. Activated Kupffer cells inhibit insulin sensitivity in obese mice.

Eradication of Helicobacter pylori prior to Roux-en-Y gastric bypass (RYGB) has been advocated as a measure to reduce the complications of anastomotic ulceration. However, evidence to support a causal relationship between preoperative H. pylori status and postoperative anastomotic ulceration is weak. Intraoperative gastric biopsies were obtained on consecutive patients who underwent laparoscopic RYGB at our institution from December 2007 to June 2010. These samples were analyzed by Warthin–Starry stain for H. Pylori organisms. Retrospective chart review was conducted to determine the preoperative presence of acid dyspepsia and acid suppression therapy and to determine postoperative ulcer symptoms, smoking, NSAID or steroid use, and compliance with ulcer prophylaxis. The incidence of ulcer visualization, perforation, and stricture were obtained from a prospectively collected database. Fisher’s exact test was used for analyzing associations between discrete groups. Multiple logistic regression was used to assess associations between anastomotic ulcer complications and potential predictors. Histologic evaluation for H. pylori was available in 708 of the 728 patients who underwent RYGB. Fourteen patients were lost to follow up leaving 694 patients available for review. H. pylori was positive in 66 (9.5 %) patients who did not go on to receive definitive treatment for eradication. Marginal ulcers or related late complications were seen in a total of 113 (16.3 %) patients. In the H. pylori positive group, five patients (7.6 %) developed ulcer complications compared to 108 (17.1 %) in the H. pylori negative group (p = 0.05). Groups were not different in terms of preoperative demographics, postoperative ulcer prophylaxis compliance, steroid, NSAIDs, and cigarette use. The presence of H. pylori infection at the time of RYGB was found to be associated with a significantly lower incidence of anastomotic ulcer complications postoperatively. This study brings into question efforts and expense allocated to identify and eradicate H. pylori prior to RYGB.

Background The purpose of the study is to investigate the association of preoperative glucose optimization prior to a Roux-en-Y gastric bypass (RYGB) and diabetes remission. Methods The study is a retrospective review of 245 patients with a history of diabetes type II and a RYGB from 2008 to 2012 at UMass Memorial Hospital. Results Patients that benefited from glucose optimization prior to RYGB were more likely to achieve diabetes remission 1 year after surgery. The preoperative glucose optimization intervention demonstrated that when patients decreased their HbA1c prior to surgery by 1 %, these individuals were 68 % more likely to remit (p=0.015). Duration of diabetes (p=0.005) and insulin use (p

PURPOSE OF REVIEW Roux-en-Y gastric bypass (RYGB) leads to remission of type 2 diabetes mellitus (T2DM) in a majority of patients. This is prompting investigation of RYGB, and other bariatric operations as interventional therapies for T2DM. RECENT FINDINGS The impact of RYGB is due to an increase in the release of gastrointestinal hormones in response to a meal [glucagon-like peptide, peptide YY, oxyntomodulin]. This effect involves the parasympathetic nervous system. These same hormones are responsible for an early increase in β-cell secretion of insulin, leading to early remission of T2DM following RYGB. Progressive weight loss leads to a later improvement in peripheral insulin sensitivity, which is required for later remissions, and is responsible for re-emergence of T2DM in individuals who regain weight in long-term follow-up. As the success of bariatric surgery has prompted the emergence of the concept that T2DM is reversible, we offer a theory to predict reversibility of diabetes after bariatric surgery that is based on baseline beta cell function. SUMMARY This review will improve the understanding of the physiology of bariatric surgery and its impact on T2DM, stimulate investigations into new avenues to treat T2DM, and allow better selection of nonobese individuals for interventional therapy of T2DM.

Background— Adipose tissue expands in response to excess caloric intake, but individuals prone to deposit visceral instead of subcutaneous adipose tissue have higher risk of metabolic disease. The role of angiogenesis in the expandability of human adipose tissue depots is unknown. The objective of this study was to measure angiogenesis in visceral and subcutaneous adipose tissue and to establish whether there is a relationship between obesity, metabolic status, and the angiogenic properties of these depots. Methods and Results— Angiogenic capacity was determined by quantifying capillary branch formation from human adipose tissue explants embedded in Matrigel, and capillary density was assessed by immunohistochemistry. Subcutaneous adipose tissue had a greater angiogenic capacity than visceral tissue, even after normalization to its higher initial capillary density. Gene array analyses revealed significant differences in expression of angiogenic genes between depots, including an increased subcutaneous expression of angiopoietin-like protein 4, which is proangiogenic in an adipose tissue context. Subcutaneous capillary density and angiogenic capacity decreased with morbid obesity, and subcutaneous, but not visceral, adipose tissue angiogenic capacity correlated negatively with insulin sensitivity. Conclusions— These data imply that subcutaneous adipose tissue has a higher capacity to expand its capillary network than visceral tissue, but this capacity decreases with morbid obesity. The decrease correlates with insulin resistance, suggesting that impairment of subcutaneous adipose tissue angiogenesis may contribute to metabolic disease pathogenesis.

Background Obesity is a strong risk factor for resistance to insulin-mediated glucose disposal, a precursor of type 2 diabetes and other disorders. However, not all obese individuals are insulin resistant. We sought to identify the molecular pathways that might cause obesity-associated insulin resistance in humans by studying the morbidly obese who were insulin sensitive versus insulin resistant, thereby eliminating obesity as a variable. Methods Combining gene expression profiling with computational approaches, we determined the global gene expression signatures of omental and subcutaneous adipose tissue samples obtained from similarly obese patients undergoing gastric bypass surgery. Results Gene sets related to chemokine activity and chemokine receptor binding were identified as most highly expressed in the omental tissue from insulin-resistant compared with insulin-sensitive subjects, independent of the body mass index. These upregulated genes included chemokines (C-C motif) ligand 2, 3, 4, and 18 and interleukin-8/(CC-X motif) ligand 8 and were not differentially expressed in the subcutaneous adipose tissues between the 2 groups of subjects. Insulin resistance, but not the body mass index, was associated with increased macrophage infiltration in the omental adipose tissue, as was adipocyte size, in these morbidly obese subjects. Conclusion Our findings have demonstrated that inflammation of the omental adipose tissue is strongly associated with insulin resistance in human obesity even in subjects with similar body mass index values.

Background Obesity is associated with a pathologic predominance of sympathetic over parasympathetic tone. With respect to the heart, this autonomic dysfunction presents as a decreased heart rate variability (HRV), which has been associated with increased cardiovascular morbidity. Gastric bypass (GB) reduces cardiovascular mortality, and, thus, could beneficially affect the HRV. We sought to identify the factors predictive of HRV in a severely obese population of undergoing GB at a university hospital in the United States. Methods The data of all patients presenting for GB were included in a prospective database. The homeostatic model of assessment (HOMA) was used to calculate the insulin resistance and glucose disposition index. A 24-hour Holter monitor was used to assess the HRV. Measurements were repeated at 2 weeks and 6 months postoperatively. The correlations between variables were determined using linear mixed models. Results We studied 30 patients undergoing GB. All exhibited some degree of reduced HRV that improved postoperatively. The HOMA-insulin resistance inversely correlated with the HRV, and the HOMA-glucose disposition index directly correlated with the parameters of HRV in our longitudinal models. Weight, body mass index, excess body weight, gender, and age did not correlate with HRV. Improvements in HRV correlated with reductions in the average heart rate, underscoring a postoperative increase in relative vagal tone. Conclusion HRV in the severely obese is better predicted by the degree of insulin resistance, than by the degree of obesity, age, or gender. GB led to an improvement in HRV, the magnitude of which correlated with the change in insulin resistance and glucose disposition index, but not with weight loss.

Background As the number of laparoscopic adjustable gastric bands (LAGBs) placed has increased, the number of patients requiring removal of the device has also increased. Methods The data from our institution, a U.S. university medical center, were reviewed to determine the feasibility, patient characteristics, and early results of converting patients from LAGB to laparoscopic Roux-en-Y gastric bypass. Results A total of 350 patients underwent LAGB placement at our institution from 2001 to 2008. Of these, 26 required conversion to laparoscopic Roux-en-Y gastric bypass for the following reasons: slippage, poor weight loss, LAGB intolerance, esophageal dilation, infection, and gastric ischemia. All conversions were completed laparoscopically. The average operating time and length of stay was 160 minutes and 3 days, respectively. Three complications developed. The average interval to conversion was 29 months. The average follow-up after conversion was 18 months. The average percentage of excess body weight loss at conversion was 23%. At 12 months after conversion, the patients had achieved an average percentage of excess body weight loss of 56% from their pre-LAGB weight. Conclusion The increasing popularity of the LAGB has led to a considerable number of revisions of the device. Our early experience has shown that converting patients from LAGB to laparoscopic Roux-en-Y gastric bypass is feasible and safe and can offer patients substantial additional weight loss.

Purpose The purpose of this study was to review the etiology and computed tomography (CT) findings of small-bowel obstruction (SBO) in patients who have undergone bariatric laparoscopic Roux-en-Y gastric bypass (LGBP) surgery. Materials and methods Prospectively entered data from a surgical database of 835 consecutive patients who underwent antecolic-antegastric LGBP for morbid obesity from June 1999 to April 2005 in a single institution were retrospectively reviewed. A total of 42 cases of bowel obstruction were observed in 41 patients. Surgical proof was available in 38 cases, and 4 cases had characteristic imaging features and/or clinical follow-up. Seventeen CT scans were reviewed to determine cause and level of obstruction, and this was correlated with surgical findings and clinical follow-up. Results Internal hernia was the most common (13 cases) and also the most frequently missed etiology of SBO on CT scans, with the diagnosis being made prospectively in only 2 of 6 cases, in which CT was done. Adhesions, ventral hernia, postoperative ileus, and jejunojejunal (JJ) anastomotic strictures, in that order, were the other commonly observed etiologies for SBO, with 11, 7, 5, and 4 cases, respectively. Some causes of SBO post-LGBP (JJ anastomotic stricture and postoperative ileus) developed relatively early, whereas others (internal hernia) tended to develop later or had a bimodal distribution (adhesions and ventral hernia). Fifteen (36%) of 42 cases had SBO at or near the level of jejunojejunostomy site; causes included internal hernia (5 cases), adhesions/kinking of small bowel (5 cases), JJ anastomotic stricture (4 cases), and JJ intussusception (1 case). Conclusion The time interval between LGBP and development of SBO might provide a useful clinical clue to its etiology. The JJ level is an important location for SBO post-LGBP because of a variety of causes, and special attention must be paid to this site at imaging of post-LGBP patients.

The traditional therapy for perforated sigmoid diverticulitis with peritonitis is emergency colectomy usually with colostomy. We report laparoscopic exploration with peritoneal lavage as an alternative in seven patients who required emergency surgery for diverticulitis. Six patients presented with diffuse peritonitis and one with a failure of percutaneous therapy. All patients were explored laparoscopically and the peritoneal cavity was lavaged with saline in addition to receiving intravenous antibiotics. Patient demographics, clinical response, length of stay, and complications were recorded. Six patients had resolution of peritonitis resolved and patients were discharged from the hospital. One of these patients who developed a pelvic abscess required a percutaneous drainage postoperatively. This patient ultimately returned 3 months later with recurrent symptoms and underwent colectomy with primary anastomosis. One patient failed to improve initially and underwent colectomy with primary anastomosis on the same admission. Five patients subsequently had elective sigmoid resections, four laparoscopic and one open. Mean length of stay was 7.7 days. There was no mortality. We conclude that laparoscopic exploration and peritoneal lavage can be performed safely in patients with diffuse, purulent peritonitis. Using this approach, most patients with purulent peritonitis can avoid emergent laparotomy with the risk of colostomy, and the need for a second surgery.

Storage of energy as triglyceride in large adipose-specific lipid droplets is a fundamental need in all mammals. Efficient sequestration of fat in adipocytes also prevents fatty acid overload in skeletal muscle and liver, which can impair insulin signaling. Here we report that the Cide domain-containing protein Cidea, previously thought to be a mitochondrial protein, colocalizes around lipid droplets with perilipin, a regulator of lipolysis. Cidea-GFP greatly enhances lipid droplet size when ectopically expressed in preadipocytes or COS cells. These results explain previous findings showing that depletion of Cidea with RNAi markedly elevates lipolysis in human adipocytes. Like perilipin, Cidea and the related lipid droplet protein Cidec/FSP27 are controlled by peroxisome proliferator-activated receptor γ (PPARγ). Treatment of lean or obese mice with the PPARγ agonist rosiglitazone markedly up-regulates Cidea expression in white adipose tissue (WAT), increasing lipid deposition. Strikingly, in both omental and s.c. WAT from BMI-matched obese humans, expression of Cidea, Cidec/FSP27, and perilipin correlates positively with insulin sensitivity (HOMA-IR index). Thus, Cidea and other lipid droplet proteins define a novel, highly regulated pathway of triglyceride deposition in human WAT. The data support a model whereby failure of this pathway results in ectopic lipid accumulation, insulin resistance, and its associated comorbidities in humans.

Use of laparoscopy in penetrating trauma has been well established; however, its application in blunt trauma is evolving. The authors hypothesized that laparoscopy is safe and feasible as a diagnostic and therapeutic modality in both the patients with penetrating and blunt trauma. Trauma registry data and medical records of consecutive patients who underwent laparoscopy for abdominal trauma were reviewed. Over a 4-year period, 43 patients (18 blunt trauma / 25 penetrating trauma) underwent a diagnostic laparoscopy. Conversion to laparotomy occurred in 9 (50%) blunt trauma and 9 (36%) penetrating trauma patients. Diagnostic laparoscopy was negative in 33% of blunt trauma and 52% of penetrating trauma patients. Sensitivity/specificity of laparoscopy in patients with blunt and penetrating trauma was 92%/100% and 90%/100%, respectively. Overall, laparotomy was avoided in 25 (58%) patients. Use of laparoscopy in selected patients with blunt and penetrating abdominal trauma is safe, minimizes nontherapeutic laparotomies, and allows for minimal invasive management of selected intra-abdominal injuries.

The association of adrenal pheochromocytoma and brown fat has been described in the pathology literature and scantily in the radiology literature. We present a case of diffuse collection of brown fat in both perinephric spaces associated with left adrenal pheochromocytoma, and describe the computed tomography and magnetic resonance imaging findings.

Cultured adipocyte cell lines are a model system widely used to study adipose function, but they exhibit significant physiological differences compared with primary cells from adipose tissue. Here we report short interfering RNA-based methodology to selectively attenuate gene expression in mouse and human primary adipose tissues as a means of rapidly validating findings made in cultured adipocyte cell lines. The method is exemplified by depletion of the PTEN phosphatase in white adipose tissue (WAT) from mouse and humans, which increases Akt phosphorylation as expected. This technology is also shown to silence genes in mouse brown adipose tissue. Previous work revealed upregulation of the mitochondrial protein UCP1 in adipose cells from mice lacking the gene for the transcriptional corepressor RIP140, whereas in cultured adipocytes, loss of RIP140 has a little effect on UCP1 expression. Application of our method to deplete RIP140 in primary mouse WAT elicited markedly increased oxygen consumption and expression of UCP1 that exactly mimics the phenotype observed in RIP140-null mice. This ex-vivo method of gene silencing should be useful in rapid validation studies as well as in addressing the depot- and species-specific functions of genes in adipose biology.

Laparoscopic adrenalectomy (LA) is a preferred method for the removal of small adrenal masses. However, the role of LA for surgical treatment of large adrenal masses is less established. We evaluated the outcomes of LA for large (>/=5 cm) adrenal masses. We retrospectively reviewed 24 consecutive patients who underwent LA for large adrenal masses at a tertiary care university hospital. The average age of the 24 patients was 49 years, and each underwent laparoscopic resection of a large adrenal mass. All LAs were performed via a lateral transperitoneal approach. The average (+/- standard deviation) size of the masses was 6.8 +/- 1.5 cm (range, 5-11). Pathologic diagnoses included adrenal cortical adenoma (10 cases), pheochromocytoma ( 7), cyst/pseudocyst ( 3), myolipoma ( 2), and adrenal cortical hyperplasia ( 2). Statistical analysis was performed with a two-sample t test. The average operating time was 178 +/- 55 minutes (range, 120-300), and average blood loss was 87 +/- 69 mL (range, 20-300); the averages were nonsignificantly greater in the right LA group than in the left LA group (203 vs. 166 minutes, P = 0.89; 124 vs. 77 mL, P = 0.14). The average duration of nothing-by-mouth (NPO) status was 0.7 days (range, 0-4), and the average time until return to a regular diet was 1.74 +/- 0.9 days (range, 1-5). The average length of stay was 2.5 +/- 1.9 days (range, 1-10). One patient had a transient episode of pseudomembranous colitis. There were no conversions to open adrenalectomy and no major morbidities or mortalities. LA is safe and effective for surgical treatment of large adrenal masses. Both right and left large adrenal masses can be approached laparoscopically with equal success. The role of minimally invasive approaches to adrenal malignancies necessitates further investigation.

The 26S proteasome degrades proteins that regulate transcription factor activation, cell cycle progression, and apoptosis. In cancer, this may allow for uncontrolled cell division, promoting tumor growth, and spread. We examined whether selective inhibition of the 26S proteasome with PS-341, a dipeptide boronic acid analogue, would block proliferation and induce apoptosis in human pancreatic cancer. Proteasome inhibition significantly blocked mitogen (FCS) induced proliferation of BxPC3 human pancreatic cancer cells in vitro, while arresting cell cycle progression and inducing apoptosis by 24 h. Accumulation of p21Cip1-Waf-1, a cyclin dependent kinase (CDK) inhibitor normally degraded by the 26S proteasome, occurred by 3 h and correlated with cell cycle arrest. When BxPC3 pancreatic cancer xenografts were established in athymic nu/nu mice, weekly administration of 1 mg/kg PS-341 significantly inhibited tumor growth. Both cellular apoptosis and p21Cip1-Waf-1 protein levels were increased in PS-341 treated xenografts. Inhibition of tumor xenograft growth was greatest (89%) when PS-341 was combined with the tumoricidal agent CPT-11. Combined CPT-11/PS-341 therapy, but not single agent therapy, yielded highly apoptotic tumors, significantly inhibited tumor cell proliferation, and blocked NF-κB activation indicating this systemic therapy was effective at the cancer cell level. 26S proteasome inhibition may represent a new therapeutic approach against this highly resistant and lethal malignancy. J. Cell. Biochem. 82: 110–122, 2001. © 2001 Wiley-Liss, Inc.

In liver transplantation, activation of NFkappaB occurs upon reperfusion, yet few data exist regarding NFkappaB activation during cold ischemia. We hypothesized that activation of NFkappaB may initially occur during cold ischemia, prior to reperfusion, and serve as an important determinant of postreperfusion function. To test this hypothesis, serial biopsies during porcine liver harvest were obtained immediately upon laparotomy, upon completion of dissection, after 45 and 120 min of cold ischemia, and 60 and 180 min after reperfusion. Nuclear extracts were isolated for Western blot analysis of NFkappaB. Hepatic function was assessed through bile output and sorbitol dehydrogenase (SDH) activity. NFkappaB expression was maximal at 45 min of cold ischemia and decreased by 120 min. The expression at 120 min of cold ischemia correlated with markers of postreperfusion function, namely bile flow and SDH activity. During reperfusion a second distinct peak occurred at 180 min. Increased expression of NFkappaB at 180 min of reperfusion correlated directly with prior expression at 120 min during cold ischemia and with increased SDH activity. These data indicate that nuclear expression of NFkappaB demonstrate two distinct peaks of activity, one during cold ischemia and one after reperfusion. Enhanced expression of NFkappaB during cold ischemia not only correlates directly with NFkappaB expression during reperfusion, but also correlates inversely with postreperfusion graft function.

Background. Genetic mutations found in pancreatic cancer (K- ras, p16, p53) lead to inappropriate cellular proliferation. Mitogens stimulate proliferation via the phosphatidylinositol 3-kinase (PI3K)- and/or the p44/42-mitogen-activated protein kinase [p44/42-MAPK or extracellular signal-regulated kinase (ERK)] signaling pathways. We examined whether inhibition of either PI3K or ERK could limit proliferation in human pancreatic cancer. Methods. Proliferation was stimulated in quiescent human pancreatic cancer cell lines (BxPC3 and Panc-1) by 10% fetal calf serum (FCS). In certain samples, PD98059 (an ERK inhibitor) or LY294002 (a PI3K inhibitor) was also added. AKT phosphorylation (indicating PI3K activity) and ERK phosphorylation (ERK activation) were determined by Western blot. Cell viability was determined by MTT assay. Cell cycle progression and apoptosis were determined by flow cytometry. A two-tailed t test was used for statistical analysis of the data (significance P Results. LY294002 inhibited the PI3K pathway without affecting ERK activation in response to serum. PD98059 inhibited the ERK pathway specifically. In both BxPC-3 and Panc-1 cell lines, LY294002 inhibited serum-induced proliferation. This was associated with G 1 cell cycle arrest and with an increase in the rate of apoptosis. PD98059 inhibited proliferation only in BxPC3 cells, and to a lesser degree than did LY294002. Conclusions. PI3K signaling appears to be necessary for G 1 -to-S phase progression and proliferation in pancreatic cancer cells. ERK plays a lesser role in mitogen-induced proliferation. Pharmacological inhibition of PI3K may decrease proliferation, increase apoptosis, and potentially confer therapeutic benefit in pancreatic cancer.

Background: Tumor necrosis factor (TNF-α)–induced apoptosis is limited by coactivation of nuclear factor kappa B (NF-kb)–dependent antiapoptotic genes. Nuclear translocation of NF-kB requires degradation of ubiquitinated phospho-IkB-a by the 26S proteasome. We examined whether inhibition of the ubiquitin-proteasome pathway enhances TNF-α–induced apoptosis in BxPC-3 human pancreatic cancer cells. Methods: Serum-starved BxPC-3 cells (12 hours) were pretreated or not for 50 minutes with PSI (30 μmol/L), a peptide aldehyde known to inhibit specifically the chymotrypsin-like activity of the 26S proteasome. Cells were subsequently stimulated with recombinant human TNF-α (400 units/mL). Western blots were performed using antibodies to IκB-α and phospho-IκB-α. Level of apoptosis was determined by two methods: enzyme-linked immunosorbent assay detection of interhistone DNA fragments and flow cytometry with propidium iodide staining. Results: TNF-α–induced degradation of IκB-α was inhibited by PSI. Phospho-IκB-α accumulation was observed 20 minutes after TNF-α stimulation. Apoptosis relative to constitutive levels was significantly increased after PSI pretreatment, as measured by DNA fragmentation (P ≤ .05 by Student t test). Percent apoptosis by flow cytometry confirmed marked increases in apoptotic cell fractions from 5.9% (untreated) to 6.8% (TNF-α alone), 16.4% (PSI alone), and 18.9% (PSI and TNF-α). Conclusions: PSI enhances both constitutive and TNF-α–induced apoptosis through inhibition of IκB-α degradation in BxPC-3 human pancreatic cancer cells. (Surgery 1999;371-7.)

Introduction. Transcriptional activation of the TNF-α gene in LPS-stimulated macrophages is dependent upon nuclear factor kappa-B (NF-κB) activity. Salicylates may interfere with NF-κB activity through a MAPK (mitogen-activated protein kinase)-dependent process. These studies investigate the effects of sodium salicylate (NaSal) on TNF-α production and MAPK activation in macrophages. Methods. Rat peritoneal macrophages were pretreated or not with sodium salicylate or ibuprofen for 1 h and then stimulated with 100 ng/ml LPS. Six hours following stimulation, cell viability was assessed by MTT assay. At specified time intervals after LPS stimulation, supernatant TNF-α was measured by ELISA. Western blots of cell lysates were performed for analysis of total and activated (phosphorylated) MAPKs. Results. Salicylate and LPS, alone or combined, did not significantly alter macrophage viability. Salicylate, but not ibuprofen, significantly reduced TNF-α production in LPS-stimulated macrophages. LPS-stimulated activation of ERK and SAPK/JNK was inhibited by NaSal pretreatment. NaSal treatment of macrophages activated p38 MAPK independent of LPS stimulation. Pretreatment of samples with the specific p38 MAPK inhibitor, SB203580, did not significantly alter TNF-α production in either LPS or NaSal and LPS-treated samples. Conclusions. Salicylates alter MAPK signaling and suppress TNF-α production in LPS-stimulated macrophages. Salicylate-induced control of inflammatory mediator production in macrophages may, in part, underlie the clinically significant anti-inflammatory effects of these compounds.

Adenocarcinoma of the pancreas carries a grave prognosis for affected patients. Certain oncogenes (K-ras and HER-2/neu) are mutated in a large proportion of these aggressive tumors. Adenocarcinoma of the pancreas has also been associated with loss of tumor suppressor genes (p53, DPC4, p16/MTS), either by deletion or by mutation and loss of function. Growth factors (EGF, TGF-alpha, HGF) and growth factor receptors (EGF-R, c-met, CCK) are expressed at levels not found in the normal pancreas. Finally, factors important for angiogenesis (FGF, integrins, selectins) are likely to play an important role in the growth and metastasis of clinically relevant tumors. This review attempts to summarize and assimilate current research into the molecular and cellular biology of pancreatic cancer.

Obese individuals may have normal insulin-glucose homeostasis, insulin resistance, or diabetes mellitus. Whereas gastric bypass cures insulin resistance and diabetes mellitus, its effects on normal physiology have not been described. We studied insulin resistance and beta-cell function for patients undergoing gastric bypass.One hundred thirty-eight patients undergoing gastric bypass had fasting insulin and glucose levels drawn on days 0, 12, 40, 180, and 365. Thirty-one (22%) patients with diabetes mellitus were excluded from this analysis. Homeostatic model of assessment was used to estimate insulin resistance, insulin sensitivity, and beta-cell function. Based on this model, patients were categorized as high insulin resistance if their insulin resistance was2.3.Body mass index did not correlate with insulin resistance. Forty-seven (34%) patients were categorized as high insulin resistance. Correction of insulin resistance for this group occurred by 12 days postoperatively. Sixty (43%) patients were categorized as low insulin resistance. They demonstrated an increase of beta-cell function by 12 days postoperatively, which returned to baseline by 6 months. At 1 year postoperatively, the low insulin resistance group had significantly higher beta-cell function per degree of insulin sensitivity.Adipose mass alone cannot explain insulin resistance. Severely obese individuals can be categorized by degree of insulin resistance, and the effect of gastric bypass depends upon this preoperative physiology.

Background: Weight loss after bariatric surgery varies and depends on many factors, such as time elapsed since surgery, baseline weight, and co-morbidities. Methods: We analyzed weight data from 494 patients who underwent laparoscopic Roux-en-Y gastric bypass (RYGBP) by one surgeon at an academic institution between June 1999 and December 2004. Linear regression was used to identify factors in predicting % excess weight loss (%EWL) at 1 year. Results: Mean patient age at time of surgery was 44 ± 9.6 (SD), and the majority were female (83.8%). The baseline prevalence of co-morbidities included 24% for diabetes, 42% for hypertension, and 15% for hypercholesterolemia. Baseline BMI was 51.5 ± 8.5 kg/m2. Mean length of hospital stay was 3.8 ± 4.6 days. Mortality rate was 0.6%. Follow-up weight data were available for 90% of patients at 6 months after RYGBP, 90% at 1 year, and 51% at 2 years. Mean %EWL at 1 year was 65 ± 15.2%. The success rate (≥50 %EWL) at 1 year was 85%. Younger age and lower baseline weight predicted greater weight loss. Males lost more weight than females. Diabetes was associated with a lower %EWL. Depression did not significantly predict %EWL. Conclusion: The study demonstrated a 65 %EWL and 85% success rate at 1 year in our bariatric surgery program. Our finding that most pre-surgery co-morbidities and depression did not predict weight loss may have implications for pre-surgery screening.

Background Exaggerated activation of peritoneal immunity after major abdominal surgery activates peritoneal macrophages (PMs), which may lead to a relative local immunosuppression. Although laparoscopy (L) is known to elicit a smaller attenuation of peritoneal host defenses, compared with open (O) surgery, effects of the hand-assisted (HA) approach have not been investigated to date. Methods Eighteen pigs underwent a transabdominal nephrectomy via O, HA, or L approach. PMs were harvested at 4, 12, and 24 hours through an intraperitoneal drain and stimulated in vitro with lipopolysaccharide. The production of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) by the purified macrophage cultures was measured with the use of a standard enzyme-linked immunosorbent assay technique. Statistical comparison was performed by using analysis of variance and Student t test. Results In vitro lipopolysaccharide–induced IL-6 and TNF-α production by PMs increased over the 24-hour period in all 3 groups. Stimulated PMs harvested at 12 and 24 hours postoperatively secreted higher levels of IL-6 in the O group, compared with both the HA group (P = .02, P = .01) and L group (P = .04, P = .001). PMs harvested at 4, 12 and 24 hours postoperatively also produced more TNF-α in O group, compared with both the HA group (P = .03, P = .03, and P = .01) and L group (P = .01, P = .05 and P = .03). There was no significant difference between H and L groups in production of either cytokine. Conclusions Abdominal surgery attenuates peritoneal host defenses regardless of the surgical approach employed. However, for the first time, we demonstrated that the HA approach, similar to laparoscopy, is superior to open surgery in the degree of PM activation. Overall, in addition to clinical benefits of minimal access, HA surgery may confer an immunologic advantage over laparotomy.

The use of a laparoscopic hand-assist device may aid in the identification of accessory spleens (ASs) and provide similar benefits to a conventional laparoscopic procedure. A patient with previous splenectomy for immune thrombocytopenic pupusa (ITP) and recurrent thrombocytopenia is reported. A computed tomography scan and RBC scan identified several nodules consistent with ASs. Initial laparoscopic exploration could not identify all the ASs seen on preoperative imaging. A hand-assist device was placed and a total of five nodules of splenic tissue were identified without conversion to laparotomy. The patient had a brief and uncomplicated postoperative course with a return of platelet counts to 350,000 at 1-month follow-up. We propose that in the scenario of recurrent ITP following laparoscopic splenectomy, repeat laparoscopy is the first step once an AS is identified by preoperative imaging. If the AS is not identified at laparoscopy, the insertion of a hand-assist device is an alternative to a full laparotomy.

Hand-assisted laparoscopic surgery (HALS) devices may be well suited to splenectomy in cases of splenomegaly.All cases of HALS for splenectomy between 1997 and 2001 were reviewed. Patient characteristics, operative details, and morbidity and mortality were analyzed.HALS for splenectomy was performed in 54 patients. A total of 39 patients with massive splenomegaly (MS) (600 g) were identified. The average weight of the MS group was 1285 +/- 505 g. There was one (3%) conversion. Operative time was 159 +/- 65 min, estimated blood loss was 257 +/- 240 ml, and length of hospital stay was 5.4 +/- 2.9 days. Morbidity was limited to 13 patients (24%), and there were two postoperative mortalities (5.1%).HALS for splenectomy in the setting of splenomegaly is feasible and safe. For the surgeon considering a laparoscopic approach in the setting of splenomegaly, a hand-assisted technique is ideally suited for removal of the enlarged spleen.

Background. FRAP-p70s6K signaling regulates mitogenic responses to growth factors in eukaryotic cells. Constitutive p70s6K activation occurs in some human malignancies and may contribute to dysregulated cell growth. We examined whether inhibition of this pathway affects mitogen-induced proliferation and cell cycle progression of human pancreatic cancer cells in vitro. Methods. Quiescent BxPC3 and Panc-1 human pancreatic cancer cells treated with or without 20 ng/mL rapamycin (FRAP inhibitor) were repleted with 10% FCS to induce cell cycle entry. Proliferation was measured with MTT assay. Cell cycle and apoptosis were determined by FACS analysis. Phosphorylation of p70s6K, Akt, and cdc2 was evaluated by Western blot. Statistical analysis was by two-tailed t test (P < 0.05). Results. Rapamycin (Rapa) inhibited the phosphorylation of p70s6K while inducing G1 cell cycle arrest (P < 0.005). In both cell lines, Rapa inhibited serum-induced proliferation (P < 0.05) without affecting apoptosis. Cdc2 phosphorylation was inhibited by 15 min with Rapa (not shown), consistent with cell cycle arrest. Akt phosphorylation was not affected, indicating FRAP specificity of Rapa. Conclusions. FRAP-p70s6K signaling appears to be necessary for G1-to-S phase progression and proliferation in pancreatic cancer cells. This supports earlier work demonstrating a similar regulatory role for PI-3′ kinase, an upstream activator of FRAP-p70s6K.

Evidence tends to support a relative preservation of the systemic immune response with laparoscopy as compared with laparotomy. However, the role of hepatic macrophages, or Kupffer cells, in modulating this immune advantage is unknown. This study investigated the functions of Kupffer cells after either laparoscopy or laparotomy in a rat model.Rats underwent laparoscopy, laparotomy, or control operations. Kupffer cells were harvested, cultured, and stimulated with lipopolysaccharide. Culture supernatants were analyzed for tumor necrosis factor (TNF-alpha) and interleukin-6 (IL-6). Cytoplasmic lysates were analyzed for activation of two mitogen-activated protein kinases (MAPKs).Production of TNF-alpha and IL-6 was similar in laparoscopy, laparotomy, and control groups. Both laparotomy and laparoscopy showed increased activation of p38 MAPK as compared with controls. Activation of ERK1/2 was decreased during laparotomy as compared with laparoscopy.Although cytokine production was similar in the laparoscopy and laparotomy groups, changes in MAPK activation suggest that intracellular pathways are more affected during laparotomy than during laparoscopy.

The mutations most common in pancreatic cancer decrease the ability to control G1 to S cell cycle progression and cellular proliferation. In colorectal cancer cells, nonsteroidal anti-inflammatory drugs inhibit proliferation and induce cell cycle arrest. We examined whether sodium salicylate, an aspirin metabolite, could inhibit proliferation in human pancreatic cancer cell lines (BxPC3 and Panc-1). Quiescent cells were treated with medium containing 10% fetal calf serum, with or without salicylate. Cellular proliferation was measured by MTT assay and bromodeoxyuridine incorporation. The fractions of cells in G0/G1, S, and G2/M phases of the cell cycle were quantitated by fluorescence-activated cell sorting. Results were compared between groups by two-tailed t test. Cyclin D1 expression was determined by Western blot analysis and prostaglandin E2 expression by enzyme-linked immunosorbent assay. Serum-starved cells failed to proliferate, with most arrested in the G1 phase. Salicylate significantly inhibited serum-induced progression from G1 to S phase, cellular proliferation, and the expression of cyclin D1. The concentrations at which 50% of serum-induced proliferation was inhibited were 1.2 mmol/L (Panc-1) and 1.7 mmol/L (BxPC3). The antiproliferative effect of sodium salicylate was not explained by inhibition of prostaglandin E2 production. This study provides further evidence in a noncolorectal cancer model for the antineoplastic effects of nonsteroidal anti-inflammatory drugs.

Tumor necrosis factor (TNF-alpha)-induced apoptosis is limited by its coactivation of nuclear factor kappa B (NF-kappaB)-dependent anti-apoptotic genes. Sodium salicylate (NaSal) inhibits NF-kappaB activation by limiting phosphorylation and degradation of its bound inhibitor protein, IkappaB-alpha. We examined whether NaSal enhances TNF-alpha-induced apoptosis in cultured human pancreatic cancer cell lines.Two cultured human pancreatic cancer cell lines were studied. PANC-1 and BxPC-3 cells were serum-starved for 12 h, pretreated or not for 1 h with NaSal (5-20 mM), and then stimulated with recombinant human TNF-alpha (400 units/ml). Western blots of cytoplasmic lysates were performed to demonstrate IkappaB-alpha phosphorylation and degradation. Western blots of nuclear extracts were performed to assess nuclear translocation of NF-kappaB. In separate cultures, apoptosis was measured 4.5 h after TNF-alpha stimulation by both ELISA detection of interhistone DNA fragments and flow cytometry with propidium iodide staining.TNF-alpha induced IkappaB-alpha phosphorylation and degradation, which was inhibited by NaSal in both cell lines. TNF-alpha-induced apoptosis (DNA fragmentation) increased significantly when BxPC-3 cells were pretreated with NaSal. Flow cytometry confirmed this, demonstrating increases in apoptotic cell fractions: 8.5% (untreated), 9.3% (TNF-alpha alone), 14.9% (15 mM NaSal), and 22.9% (NaSal and TNF-alpha). In contrast, no increases in apoptosis were measured in the PANC-1 cell line among the various treatment groups.NaSal enhances TNF-alpha-induced apoptosis while inhibiting IkappaB-alpha phosphorylation and degradation in BxPC-3 human pancreatic cancer cells.

Hypothesis An analysis of patients undergoing laparoscopic Roux-en-Y gastric bypass (RYGB) may identify factors predictive of complication and of suboptimal weight loss. Design Inception cohort. Setting Metropolitan university hospital. Patients One hundred eighty-eight consecutive patients with severe obesity who met National Institutes of Health consensus guidelines for bariatric surgery. Interventions Laparoscopic RYGB. Main Outcome Measures Complications requiring therapeutic intervention and percentage of excess body weight lost at 1 year after surgery. Results Of the 188 patients who underwent laparoscopic RYGB, 50 (26.6%) developed complications that required an invasive therapeutic intervention, including 2 deaths. The average follow-up was 351 days (range, 89-1019 days). Multivariate analysis by stepwise logistic regression identified surgeon experience, sleep apnea ( P = .003; odds ratio, 3.0; 95% confidence interval, 1.3-7.1), and hypertension ( P = .07; odds ratio, 2.0; 95% confidence interval, 1.0-4.0) as predictors of complications. The most common complication requiring therapeutic intervention was stricture at the gastrojejunal anastomosis, occurring in 27 patients (14.4%). Of the 115 patients who underwent surgery more than 1 year previously, 1-year follow-up data were available for 93 (81%). The body mass index (weight in kilograms divided by the square of height in meters) decreased from 53 ± 8 preoperatively to 35 ± 6 at 1 year. The mean ± SD percentage of excess body weight lost at 1 year was 61% ± 14%. Diabetes mellitus was negatively correlated with percentage of excess body weight lost at 1 year ( P = .06). Conclusions Surgeon experience, sleep apnea, and hypertension are associated with complications after laparoscopic RYGB. Diabetes mellitus may be associated with poorer postoperative weight loss.