Prospective Evaluation of Ultrasound and Colour Duplex Imaging for the Assessment of Surgical Resectability of Pancreatic Tumours

Langenbeck's Archives of Surgery / Deutsche Gesellschaft Für Chirurgie. Dec, 2003  |  Pubmed ID: 12910422

This study was performed to evaluate colour duplex imaging (CDI) for the assessment of resectability of pancreatic tumours (PTs).

Management and Outcome of Hemorrhage Due to Arterial Pseudoaneurysms in Pancreatitis

Surgery. Mar, 2005  |  Pubmed ID: 15746787

Arterial pseudoaneurysm formation in pancreatitis is a rare complication. The optimal treatment modality is controversial. Operative treatment and interventional treatment, either alone or as a temporizing method with a later operation, are options.

Effect of Oxygenated Perfluorocarbons on Isolated Rat Pancreatic Islets in Culture

Cell Transplantation. 2005  |  Pubmed ID: 16285252

One impediment for a wider application of islet transplantation is the limited number of donor pancreata for islet isolation. A more efficient utilization of available organs could in part alleviate this problem. Perfluorocarbons (PFCs) have a high oxygen solubility coefficient and maintain high oxygen partial pressures for extended time. They serve also as oxygen "reservoirs" for harvested organs in pancreas organ transplantation. The aim of this study was to test whether the use of PFCs could also be beneficial for the secretory activity and overall viability of cultured purified islets before transplantation. Purified rat islets were cultured in static conditions with or without oxygen-saturated PFCs for 1 or 7 days. Cell death and apoptosis were assessed by trypan blue staining, DNA strand breaks, and caspase 3/7 activity. mRNA levels of insulin and ICA512/IA-2, a membrane marker of secretory granules (SGs), were quantitated by real-time PCR, whereas insulin content and secretion were measured by RIA. Polypyrimidine tract binding protein (PTB), which promotes SG biogenesis, was assessed by Western blotting. The number of SGs and the ultrastructural appearance of beta5-cells were analyzed by cryoimmunoelectronmicroscopy for insulin. Various parameters, including caspase activity, insulin and ICA512/IA-2 mRNA levels, PTB expression, number of secretory granules, and ultrastructural appearance did not significantly differ between control and PFC-cultured islets. On the other hand, PFC culture islets showed significantly increased DNA fragmentation and a reduced insulin stimulation index at both time points compared to control islets. While advantageous for the transport of human harvested organs, the use of PFH in the culture may be comparable to and/or not provide advantage over conventional protocols for culture of islets for transplantation.

CAMP-dependent Phosphorylation of PTB1 Promotes the Expression of Insulin Secretory Granule Proteins in Beta Cells

Cell Metabolism. Feb, 2006  |  Pubmed ID: 16459313

Glucose stimulates the exocytosis of insulin secretory granules of pancreatic beta cells. Granule stores are quickly refilled by activation of posttranscriptional mechanisms that enhance the biosynthesis of granule components. Rapid replacement of granules is important to sustain insulin secretion, since new granules appear to be preferentially released. Posttranscriptional regulation of granule biogenesis includes the glucose-induced nucleocytoplasmic translocation of polypyrimidine tract binding protein 1 (PTB1), which binds mRNAs encoding granule proteins, and thus promotes their stabilization and translation. Glucagon-like peptide 1 (GLP-1) potentiates glucose-stimulated insulin gene expression and secretion by increasing cAMP levels in beta cells. Here, we show that elevation of cAMP levels causes the protein kinase A-dependent phosphorylation and nucleocytoplasmic translocation of PTB1, thereby preventing the rapid degradation of insulin mRNA and enhancing the expression of various granule proteins. Taken together, these findings identify PTB1 as a common downstream target of glucose and GLP-1 for the posttranscriptional upregulation of granule biogenesis.

Synergy of Glucose and Growth Hormone Signalling in Islet Cells Through ICA512 and STAT5

Nature Cell Biology. May, 2006  |  Pubmed ID: 16622421

Nutrients and growth hormones promote insulin production and the proliferation of pancreatic beta-cells. An imbalance between ever-increasing metabolic demands and insulin output causes diabetes. Recent evidence indicates that beta-cells enhance insulin gene expression depending on their secretory activity. This signalling pathway involves a catalytically inactive receptor tyrosine phosphatase, ICA512, whose cytoplasmic tail is cleaved on glucose-stimulated exocytosis of insulin secretory granules and then moves into the nucleus, where it upregulates insulin transcription. Here, we show that the cleaved cytosolic fragment of ICA512 enhances the transcription of secretory granule genes (including its own gene) by binding to tyrosine phosphorylated signal transducers and activators of transcription (STAT) 5 and preventing its dephosphorylation. Sumoylation of ICA512 by the E3 SUMO ligase PIASy, in turn, may reverse this process by decreasing the binding of ICA512 to STAT5. These findings illustrate how the exocytosis of secretory granules, through a retrograde pathway that sustains STAT activity, converges with growth hormone signalling to induce adaptive changes in beta-cells in response to metabolic demands.

Prospective Evaluation of the Retrograde Percutaneous Translaryngeal Tracheostomy (Fantoni Procedure) in a Surgical Intensive Care Unit: Technique and Results of the Fantoni Tracheostomy

Head & Neck. Apr, 2006  |  Pubmed ID: 16284980

Controversy surrounds the safety and practicality of the retrograde percutaneous translaryngeal tracheostomy (Fantoni procedure) compared with other percutaneous methods.

Location of Liver Metastases Reflects the Site of the Primary Colorectal Carcinoma

Scandinavian Journal of Gastroenterology. 2008  |  Pubmed ID: 17918001

The present study was designed to investigate whether the different venous return of different locations of colorectal carcinomas affects the lobar distribution of metastases to the liver, due to the "streaming" within the portal vein.

Color Doppler Imaging Predicts Portal Invasion by Pancreatic Adenocarcinoma

Annals of Surgical Oncology. Apr, 2008  |  Pubmed ID: 18095029

Tumor infiltration of the intima of the portal vein (PV) and superior mesenteric vein (SMV) by pancreatic adenocarcinoma is classically considered a criterion for unsuitability for resection and poor prognosis. This study was performed to evaluate modern color duplex imaging (CDI) for the assessment of PV/SMV infiltration by pancreatic adenocarcinomas.

ICA512 Signaling Enhances Pancreatic Beta-cell Proliferation by Regulating Cyclins D Through STATs

Proceedings of the National Academy of Sciences of the United States of America. Jan, 2008  |  Pubmed ID: 18178618

Changes in metabolic demands dynamically regulate the total mass of adult pancreatic beta-cells to adjust insulin secretion and preserve glucose homeostasis. Glucose itself is a major regulator of beta-cell proliferation by inducing insulin secretion and activating beta-cell insulin receptors. Here, we show that islet cell autoantigen 512 (ICA512)/IA-2, an intrinsic tyrosine phosphatase-like protein of the secretory granules, activates a complementary pathway for beta-cell proliferation. On granule exocytosis, the ICA512 cytoplasmic domain is cleaved and the resulting cytosolic fragment (ICA512-CCF) moves into the nucleus where it enhances the levels of phosphorylated STAT5 and STAT3, thereby inducing insulin gene transcription and granule biogenesis. We now show that knockdown of ICA512 decreases cyclin D1 levels and proliferation of insulinoma INS-1 cells, whereas beta-cell regeneration is reduced in partially pancreatectomized ICA512-/- mice. Conversely, overexpression of ICA512-CCF increases both cyclin D1 and D2 levels and INS-1 cell proliferation. Up-regulation of cyclin D1 and D2 by ICA512-CCF is affected by knockdown of STAT3 and STAT5, respectively, whereas it does not require insulin signaling. These results identify ICA512 as a regulator of cyclins D and beta-cell proliferation through STATs and may have implication for diabetes therapy.

Resection of Colorectal Liver Metastases: is a Resection Margin of 3 Mm Enough? : a Multicenter Analysis of the GAST Study Group

World Journal of Surgery. Sep, 2008  |  Pubmed ID: 18521661

A safety margin of > or =10 mm is generally accepted in surgery for colorectal metastases. It is reasonable that modern methods of liver parenchyma dissection may allow for a reduction in this distance.

Prognostic Factors and Evaluation of a Clinical Score for Predicting Survival After Resection of Colorectal Liver Metastases

Liver International : Official Journal of the International Association for the Study of the Liver. Jan, 2009  |  Pubmed ID: 18673436

Patient outcome after resection of colorectal liver metastases can be predicted by various prognostic factors. Aims: Development of a model for risk stratification based on analysis of prognostic factors.

Colorectal Liver Metastasis Surgery: Analysis of Risk Factors Predicting Postoperative Complications in Relation to the Extent of Resection

International Journal of Colorectal Disease. Jun, 2009  |  Pubmed ID: 19214537

Despite advances in diagnosis and treatment, the rate of complications after resection for colorectal liver metastases remains high. An awareness of risk factors is essential for the rates of morbidity and mortality to fall to optimal levels.

Curative Resection of a Primarily Unresectable Acinar Cell Carcinoma of the Pancreas After Chemotherapy

World Journal of Surgical Oncology. 2009  |  Pubmed ID: 19239719

Acinar cell carcinoma (ACC) represents only 1-2% of pancreatic cancers and is a very rare malignancy. At the time of diagnosis only 50% of the tumors appear to be resectable. Reliable data for an effective adjuvant or neoadjuvant treatment are not available.

Surgical Therapy of Intrapancreatic Metastasis from Renal Cell Carcinoma

Pancreatology : Official Journal of the International Association of Pancreatology (IAP) ... [et Al.]. 2009  |  Pubmed ID: 19468247

Pancreatic metastases from renal cell carcinoma (RCC) are clinically rare but highly resectable. The aim of this article is to identify patients who profit from pancreatic resection of RCC despite the invasiveness of the surgery.

Who Profits from Neoadjuvant Radiochemotherapy for Locally Advanced Esophageal Carcinoma?

Journal of Gastroenterology and Hepatology. May, 2009  |  Pubmed ID: 19655439

Patients suffering from locally advanced esophageal carcinoma are generally treated using multimodal therapies. This prospective, non-randomized trial was performed to evaluate the survival benefit of neoadjuvant radiochemotherapy prior to surgery in comparison with surgery only.

Quantitative Perfusion Analysis of Transabdominal Contrast-enhanced Ultrasonography of Pancreatic Masses and Carcinomas

Gastroenterology. Dec, 2009  |  Pubmed ID: 19715694

Preoperative differential diagnosis of pancreatic ductal adenocarcinoma (PDAC) and focal masses in patients with chronic pancreatitis (CP) can be challenging. There are fine differences in the vascularization of these lesions; ultrasound contrast agents can aid in their differentiation. We evaluated the value of software-aided quantitative analysis of transabdominal contrast-enhanced ultrasonography for differential diagnosis of PDAC vs focal masses.

Palliative Treatment of Obstructive Jaundice in Patients with Carcinoma of the Pancreatic Head or Distal Biliary Tree. Endoscopic Stent Placement Vs. Hepaticojejunostomy

JOP : Journal of the Pancreas. 2010  |  Pubmed ID: 21068488

Palliative procedures play an important role in the treatment of malignancies of the pancreatic head/distal biliary tree, as only 20-30% can be cured by surgical resection.

Impaired Insulin Turnover in Islets from Type 2 Diabetic Patients

Islets. Jan-Feb, 2010  |  Pubmed ID: 21099291

Failure of pancreatic β-cells contributes to the development of type 2 diabetes. Besides evidence of reduced glucose-stimulated insulin secretion and β-cell mass, little information is available about the molecular deficits of human diabetic islets. Islets were isolated from macroscopically normal pancreatic tissue from 8 patients with type 2 diabetes and 17 matched non-diabetic patients who underwent pancreatic surgery. Insulin content and insulin secretion were measured before and after islet stimulation with 25 mM glucose for 2 hours. In parallel, we also investigated the subcellular localization of polypyrimidine tract-binding protein 1 (PTBP1), whose nucleocytoplasmic translocation is involved in the rapid posttranscriptional up-regulation of insulin biosynthesis following islet stimulation with glucose and GLP-1. Glucose stimulated insulin secretion was decreased, albeit not significantly, in type 2 diabetic islets compared to non-diabetic islets. Stimulation increased the total amount of insulin (islet insulin content + secreted insulin) in islet preparation from non-diabetic patients, but not from type 2 diabetic subjects. Furthermore, the nuclear levels of PTBP1 were decreased in stimulated non-diabetic islets, but not in type 2 diabetic islets. These results suggest that impairment of rapid insulin increase in response to glucose is a specific trait of type 2 diabetic islets. Nuclear retention of PTBP1 is likely to play a role in this deficit, which in turn can contribute to impaired insulin secretion in type 2 diabetes. Overall, these data highlight the importance of investigating mechanisms of insulin biosynthesis and degradation to gain insight into the pathogenesis of type 2 diabetes.

Transabdominal Contrast-enhanced Ultrasonography of Pancreatic Cancer

Pancreatology : Official Journal of the International Association of Pancreatology (IAP) ... [et Al.]. 2011  |  Pubmed ID: 21464583

Since its introduction, contrast-enhanced ultrasonography (CEUS) has significantly extended the value of ultrasonography (US). CEUS can be used to more accurately determine pancreatic lesions compared to conventional US or to characterize lesions already detectable by US. Thus, CEUS can aid in the differential diagnosis of pancreatic tumors. Using US contrast media, it is possible to visually detect microvessels in the majority of pancreatic ductal adenocarcinomas. Thus, the use of quantitatively evaluated transabdominal CEUS can help in the differentiation of patients with mass-forming pancreatitis from patients with pancreatic adenocarcinomas. In neuroendocrine pancreatic tumors, different enhancement patterns can be observed in relation to the tumor mass: larger ones show a rapid early enhancement sometimes combined with necrotic central structures, and smaller ones disclose a capillary-blush enhancement. Pseudocysts, the most widespread cystic lesions of the pancreas, are not vascularized. They do not show any signal in CEUS and remain entirely anechoic in all phases, while true cystic pancreatic tumors usually have vascularized septa and parietal nodules. In summary, CEUS is effective for differentiating solid pancreatic tumors in most cases. CEUS is safe and cost effective and can better discriminate solid from cystic pancreatic lesions, thereby directing further imaging modalities.

Chronic Pancreatitis: Early Results of Pancreatoduodenectomy and Analysis of Risk Factors

Pancreas. Aug, 2011  |  Pubmed ID: 21487322

Although mortality after pancreatoduodenectomy for chronic pancreatitis has declined, the complication rate remains high. Today, there is an increasing need to base clinical decisions on the available scientific evidence to provide the best available treatment for the patients. Therefore, we retrospectively analyzed comprehensive preoperative and postoperative characteristics of patients undergoing pancreatic head resection for chronic pancreatitis and performed an outcome analysis to provide prospective selection or managing criteria that could improve the early surgical results.

Hepatocyte Nuclear Factor (HNF) 4α Expression Distinguishes Ampullary Cancer Subtypes and Prognosis After Resection

Annals of Surgery. Aug, 2011  |  Pubmed ID: 21494118

To investigate biological differences and prognostic indicators of different ampullary cancer (AC) subtypes.

Risk Factors for Morbidity and Mortality After Single-layer Continuous Suture for Ileocolonic Anastomosis

International Journal of Colorectal Disease. Mar, 2011  |  Pubmed ID: 20697722

The study was designed to determine the suitability of a single-layer continuous anastomosis for ileo-colonic anastomoses and to determine perioperative risk factors for morbidity and mortality in a teaching hospital.

Colorectal Liver Metastases: an Update on Palliative Treatment Options

Journal of Gastrointestinal and Liver Diseases : JGLD. Mar, 2012  |  Pubmed ID: 22457864

Only approximately 30% of patients with colorectal cancer liver metastasis qualify for curative therapy, which is in most cases liver lesion resection. Due primarily to the extent of the tumors and patient comorbidities, palliative therapy remains the only option in non-resection cases. Palliation enables local, symptomatic control and prolonged survival in some cases. As established methods are continuously improved, new palliative therapy methods are tested in clinical trials and subsequently introduced into clinical practice. The present review provides an overview of current colorectal liver metastasis treatment when resection is not an option. This review gives the basis for an interdisciplinary decision making process for the treatment of liver metastasis.

Google Goes Cancer: Improving Outcome Prediction for Cancer Patients by Network-based Ranking of Marker Genes

PLoS Computational Biology. 2012  |  Pubmed ID: 22615549

Predicting the clinical outcome of cancer patients based on the expression of marker genes in their tumors has received increasing interest in the past decade. Accurate predictors of outcome and response to therapy could be used to personalize and thereby improve therapy. However, state of the art methods used so far often found marker genes with limited prediction accuracy, limited reproducibility, and unclear biological relevance. To address this problem, we developed a novel computational approach to identify genes prognostic for outcome that couples gene expression measurements from primary tumor samples with a network of known relationships between the genes. Our approach ranks genes according to their prognostic relevance using both expression and network information in a manner similar to Google's PageRank. We applied this method to gene expression profiles which we obtained from 30 patients with pancreatic cancer, and identified seven candidate marker genes prognostic for outcome. Compared to genes found with state of the art methods, such as Pearson correlation of gene expression with survival time, we improve the prediction accuracy by up to 7%. Accuracies were assessed using support vector machine classifiers and Monte Carlo cross-validation. We then validated the prognostic value of our seven candidate markers using immunohistochemistry on an independent set of 412 pancreatic cancer samples. Notably, signatures derived from our candidate markers were independently predictive of outcome and superior to established clinical prognostic factors such as grade, tumor size, and nodal status. As the amount of genomic data of individual tumors grows rapidly, our algorithm meets the need for powerful computational approaches that are key to exploit these data for personalized cancer therapies in clinical practice.

[In Process Citation]

Zentralblatt Für Chirurgie. Aug, 2012  |  Pubmed ID: 22933001

Contrast-enhanced Ultrasonography in Pancreas Transplantation

Transplantation. Jan, 2013  |  Pubmed ID: 23222819

Pancreas transplantation remains a major surgery with potential complications that require reliable imaging despite impaired kidney function. Contrast-enhanced ultrasonography (CEUS) has been proven to be an indispensable tool in the evaluation of the native pancreas. Here, CEUS studies are extended to pancreas transplants for the first time.