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Transmission based on flows becomes more and more popular in teleinformatics networks. To guarantee proper quality of service, to enable multipath transmissions, or just to increase transmission effectiveness in a network, traffic should be sent as flows. Flow-aware networking architecture is one of the possible concepts to realize flow-based transmissions. In this paper, the efficient congestion control mechanism (ECCM) is proposed to improve transmission in flow-aware networks (FAN). The mechanism makes it possible to minimize acceptance delay of streaming flows (served with high priority) without deteriorating other transmissions in the network. It is confirmed by simulation experiments that the implementation of FAN with the ECCM mechanism is a promising solution for the Future Internet. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Liver transplantation is a well-established treatment of patients with end-stage liver disease and selected liver tumors. Remarkable progress has been made over the last years concerning nearly all of its aspects. The aim of this study was to evaluate the evolution of long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery (Medical University of Warsaw). Material and methods. Data of 1500 liver transplantations performed between 1989 and 2014 were retrospectively analyzed. Transplantations were divided into 3 groups: group 1 including first 500 operations, group 2 including subsequent 500, and group 3 comprising the most recent 500. Five year overall and graft survival were set as outcome measures. Results. Increased number of transplantations performed at the site was associated with increased age of the recipients (p<0.001) and donors (p<0.001), increased rate of male recipients (p<0.001), and increased rate of piggyback operations (p<0.001), and decreased MELD (p<0.001), as well as decreased blood (p=0.006) and plasma (p<0.001) transfusions. Overall survival was 71.6% at 5 years in group 1, 74.5% at 5 years in group 2, and 85% at 2.9 years in group 3 (p=0.008). Improvement of overall survival was particularly observed for primary transplantations (p=0.004). Increased graft survival rates did not reach the level of significance (p=0.136). Conclusions. Long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery are comparable to those achieved in the largest transplant centers worldwide and are continuously improving despite increasing recipient age and wider utilization of organs procured from older donors. [ABSTRACT FROM AUTHOR]

Background. The aim of a research was an assessment of a colorectal neoplasmatic leasons risk in group of diabetes type 2 patients in comparison to healthy patients. Material and methods. We analysed 239 patients without diabetes (151 women, 88 men; 61.8 ± 15.5 years) and 43 with diabetes (26 women, 17 men; 66.4 ± 12.2 years) who underwent colonoscopy between May 2005 and December 2006. Tissue samples taken from observed leasons were histologicaly evaluated. The χ2, U Mann-Whitney’s test and logistic regression were used in statistical analysys. Results. Impact on the prevalence of adenocarcinoma have: presence of diabetes, masculine sex (OR: 2.8) and age (OR: 1.04 on every 5 years more). In group of diabetes type 2 patients in compare to control group the prevalence of adenocarcinoma was higher (P = 0.02). Impact of diabetes type 2 as an adnocarcinoma risk factor was independent from age, WHR, waist circumference and obesity measured with BMI. Coincidence of diabetes type 2 alters the risk of adenocarcinoma 3 times (95%CI: 1.9–9.3). We payed attention on high coincidence of polyps and adenocarcinoma in analysed group. Within all histological types of polyps the hyperplastic one dominated in analysed group and that was statistically important (P = 0.0039). Conclusions. Diabetes type 2 alters the prevalence risk of adenocarcinoma (OR: 3.0) independently from sex, age, waist circumference and BMI. We did not find positive correlation between the presence of diabetes and colon polyps. [ABSTRACT FROM AUTHOR]

Introduction: Approximately 20% of cases of colorectal cancer are accompanied by acute colonic obstruction. While emergency colonic surgery is associated with high mortality and morbidity rates, placement of a self-expanding metal stent (SEMS) has been suggested as an alternative method. The SEMS placement can serve as either a definitive treatment in palliative cases or a bridge to surgery., Aim: To summarize the experience of our center in the treatment of malignant colonic obstruction using SEMS placement., Material and Methods: A retrospective review was conducted of all patients who underwent a SEMS placement for colorectal stricture in the study period. The procedures were performed under fluoroscopic guidance with colonoscopic assistance, and uncovered stents were used in all patients., Results: The study population consisted of 28 patients treated with SEMS placement due to malignant colonic obstruction. The majority of procedures were performed with palliative intent. The overall technical success rate was 96.5%, and clinical success was achieved in all of the successfully placed SEMSs. One fatal complication due to colonic perforation occurred. In the bridge-to-surgery group, all patients experienced tumor resection with no stoma creation., Conclusions: The SEMS placement is an optimal treatment in the vast majority of acute colonic obstruction cases. Due to the possibility of potentially fatal complications, SEMS procedures should be performed by proficient endoscopists.

Unlabelled: Liver transplantation is a well-established treatment of patients with end-stage liver disease and selected liver tumors. Remarkable progress has been made over the last years concerning nearly all of its aspects. The aim of this study was to evaluate the evolution of long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery (Medical University of Warsaw)., Material and Methods: Data of 1500 liver transplantations performed between 1989 and 2014 were retrospectively analyzed. Transplantations were divided into 3 groups: group 1 including first 500 operations, group 2 including subsequent 500, and group 3 comprising the most recent 500. Five year overall and graft survival were set as outcome measures., Results: Increased number of transplantations performed at the site was associated with increased age of the recipients (p<0.001) and donors (p<0.001), increased rate of male recipients (p<0.001), and increased rate of piggyback operations (p<0.001), and decreased MELD (p<0.001), as well as decreased blood (p=0.006) and plasma (p<0.001) transfusions. Overall survival was 71.6% at 5 years in group 1, 74.5% at 5 years in group 2, and 85% at 2.9 years in group 3 (p=0.008). Improvement of overall survival was particularly observed for primary transplantations (p=0.004). Increased graft survival rates did not reach the level of significance (p=0.136)., Conclusions: Long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery are comparable to those achieved in the largest transplant centers worldwide and are continuously improving despite increasing recipient age and wider utilization of organs procured from older donors.

Unlabelled: Resection of the gall-bladder is still the most common surgical procedure performed at general surgery departments. The laparoscopic method used in the majority of cases offers considerable benefits but at the same time is associated with an increased rate of bile duct complications. So far, a slim female aged 25-50 years was a typical patient with a iatrogenic bile duct injury. The aim of the study was to identify the age of patients with iatrogenic bile duct injuries as well as the clinical course observed in recent years., Material and Methods: Gender and age structure of patients admitted to the Department of General, Transplant and Liver Surgery between the beginning of 2011 and June 2014 and treated for iatrogenic bile duct injuries, complications of laparoscopic cholecystectomy, were analysed. The patients were referred to the department as a reference centre., Results: In the group of 186 patients, females predominated (69.4%) and the mean age was 52 years. A considerable increase in the mean age of patients treated in 2014 as compared with previous years was seen. This was related to an increased rate of bile duct injuries in patients aged over 70 years, who accounted for about 25% of the group. In previous years, bile duct injuries in patients of such an advanced age happened considerably less frequently., Conclusions: A iatrogenic bile duct injury in an elderly person may prove a fatal complication. A repair surgery, i.e. the biliary-enteric anastomosis, is a major and burdensome procedure, particularly in the case of patients aged over 70 years. Special caution during laparoscopic cholecystectomy is advised in this population, and the slightest doubts should lead to conversion.

Hemangiomas are the most common benign primary hepatic neoplasms, often being incidentally discovered. In most of the cases they are small and asymptomatic. It is widely accepted that clinical intervention is indicated only for symptomatic hemangiomas. We present a case of an asymptomatic giant hemangioma managed by enucleation due to its atypical localization. The hemangioma, originally located in segment 5, was now described in Computer Tomography (CT) Imaging as separating the gallbladder from the liver parenchyma. A careful evaluation of images revealed proximity to the portal vein (PV), right hepatic artery (RHA), right hepatic duct (RHD) and right branch of the portal vein (RBPV). Thus, in the case of an emergent operation, surgical maneuvers in the area of the altered hepatic anatomy and proximity to the hemangioma itself, would in fact increase the risk endangering the patient's life. After patient's consent, a surgical enucleation en block with the gall-bladder was performed. It is of great importance that specifically selected, asymptomatic patients diagnosed with a giant hemangioma, with the above mentioned or similar localization should be considered for surgical treatment.

Anatomic variations of the right biliary system are one of the most common risk factors for sectoral bile duct injury (BDI) during cholecystectomy. Isolated right posterior BDI may in particular be a challenge for both diagnosis and management. Herein we describe two cases of isolated right posterior sectoral BDI that took place during laparoscopic cholecystectomy. Despite effective external biliary drainage from the liver hilum in both cases, there was a persistent biliary leak observed which was not visible on endoscopic retrograde cholangiogram. Careful evaluation of images from both endoscopic and magnetic resonance cholangiograms revealed the diagnosis of an isolated right posterior sectoral BDI. These were treated with a delayed bisegmental (segments 6 and 7) liver resection and a Roux-en-Y hepaticojejunostomy respectively with good outcomes at 24 and 4 mo of follow-up. This paper discusses strategies for prevention of such injuries along with the diagnostic and therapeutic challenges it offers.

Introduction: Cirrhosis related to hepatitis C virus (HCV) and hepatitis B virus (HBV) infection is the most frequent indication for liver transplantation worldwide. Progress in prophylaxis of posttransplant HBV recurrence has led to major improvements in long-term outcomes of patients after liver transplantation. Conversely, impaired posttransplant survival of patients with HCV infection was reported in several studies, mainly due to recurrence of viral infection. The purpose of this study was to compare long-term results of liver transplantation between patients with HBV monoinfection, HCV monoinfection and HBV/HCV coinfection., Material and Methods: A total of 1090 liver transplantations were performed in the Department of General, Transplant and Liver Surgery in cooperation with the Department of Immunology, Internal Medicine, and Transplantology at the Transplantation Institute Medical University of Warsaw between December 1994 and May 2012. After exclusion of patients with cirrhosis of non-viral etiology, patients with malignant tumors, and patients with acute liver failure, the final study cohort comprised 209 patients with HBV (HBV+/HCV- subgroup; n = 56) or HCV (HBV-/HCV+ subgroup; n = 119) monoinfection or HBV/HCV coinfection (HBV+/HCV+; n = 34). These subgroups of patients were compared in terms of long-term results of transplantations, defined by 5-year patient and 5-year graft survival estimates., Results: Overall and graft survival rates after 5-years for the whole study cohort were 74.5% and 72.6%, respectively. Five-year overall survival was 70.4% for patients within the HBV+/HCV- subgroup, 77.8% for patients within the HBV-/HCV+ subgroup, and 68.5% for patients within the HBV+/HCV+ subgroup. The corresponding rates of graft survival were 67.0%, 76.3%, and 68.5% for patients within the HBV+/HCV-, HBV-/ HCV+, and HBV+/HCV+ subgroups, respectively. Observed differences were non-significant, both in terms of overall (p = 0.472) and graft (p = 0.461) survival rates., Conclusions: Both overall and graft survival rates after liver transplantations performed in the Department of General, Transplant and Liver Surgery in cooperation with the Department of Immunology, Internal Medicine, and Transplantology at the Transplantation Institute Medical University of Warsaw in patients with HBV and HCV infection are comparable to those reported by other European and American centers. In contrast to other studies, obtained results do not confirm the negative impact of HCV infection on long-term outcomes of patients.

The Aim of the Study: was to analyze indications and results of the first one thousand liver transplantations at Chair and Clinic of General, Transplantation and Liver Surgery, Medical University of Warsaw., Material and Methods: Data from 1000 transplantations (944 patients) performed at Chair and Clinic of General, Transplantation and Liver Surgery between 1994 and 2011 were analyzed retrospectively. These included 943 first transplantations and 55 retransplantations and 2 re-retransplantations. Frequency of particular indications for first transplantation and retransplantations was established. Perioperative mortality was defined as death within 30 days after the transplantation. Kaplan-Meier survival analysis was used to estimate 5-year patient and graft survival., Results: The most common indications for first transplantation included: liver failure caused by hepatitis C infection (27.8%) and hepatitis B infection (18%) and alcoholic liver disease (17.7%). Early (< 6 months) and late (> 6 months) retransplantations were dominated by hepatic artery thrombosis (54.3%) and recurrence of the underlying disease (45%). Perioperative mortality rate was 8.9% for first transplantations and 34.5% for retransplantations. Five-year patient and graft survival rate was 74.3% and 71%, respectively, after first transplantations and 54.7% and 52.9%, respectively, after retransplantations., Conclusions: Development of liver transplantation program provided more than 1000 transplantations and excellent long-term results. Liver failure caused by hepatitis C and B infections remains the most common cause of liver transplantation and structure of other indications is consistent with European data.