Recurrence rate of hepatocellular carcinoma in patients with treated hepatocellular carcinoma and hepatitis C virus-associated cirrhosis after ombitasvir/paritaprevir/ritonavir+dasabuvir+ribavirin therapy

Introduction

Recent studies have suggested a higher recurrence rate of hepatocellular carcinoma (HCC) in patients with a history of HCC and hepatitis C virus (HCV)-associated cirrhosis treated with direct-acting antiviral (DAA) agents.

Material and methods

We conducted a prospective analysis of 24 patients with HCV-associated cirrhosis and treated HCC who received ombitasvir/paritaprevir/ritonavir+dasabuvir+ribavirin for 12 weeks. Prior therapies for HCC included resection (9/24 patients), radiofrequency ablation (RFA) (7/24) and trans-arterial chemoembolization (TACE) (8/24). All patients were eligible for treatment if they had no HCC recurrence 6 months after their last procedure. A control group was defined. All patients were followed every 6 months, with dynamic computed tomography and/or magnetic resonance imaging.

Results

The sustained virological response rate per protocol was 21/24 (87.5%). The study group included 14 (59%) males, median age 64 years (51-77), 50% with associated non-alcoholic steatohepatitis and 24% with Child-Pugh A6 points. HCC recurrence rate/100 patient-years was lower in the DAA-HCC group versus control: 5.5 versus 24.6% patient-years for the resection+RFA group (p = 0.044), respectively, and 18.6 versus 72.7% patient-years for TACE group (p = 0.002). Survival without recurrence was higher in the resection+RFA group (45 compared to 18 months (p < 0.001)) and also in the TACE group (44 compared to 11.5 months (p = 0.002)).

Conclusions

DAA therapy significantly reduced the recurrence rate of HCC and improved survival without recurrence in patients with treated HCV-associated HCC.

Splenic Cysts: A Strong Indication for a Minimally Invasive Partial Splenectomy. Could the Splenic Hilar Vasculature Type Hold a Defining Role?

BACKGROUND

The aim of the study is to assess the impact of the splenic hilar vasculature configuration on the amount of remnant splenic parenchyma volume after partial splenectomy for splenic cysts.

METHODS

The data of all patients receiving a splenectomy for a splenic cyst from 2002 to 2016 at the Center of General Surgery and Liver Transplantation of Fundeni Clinical Institute were retrospectively reviewed. The size and location in the splenic parenchyma of the cyst and the splenic hilar vasculature type were assessed for each patient with a splenectomy.

RESULTS

Thirty-one patients with non-parasitic and 32 patients with hydatid cysts were recorded. In cases of centrally located cysts, a total splenectomy was performed for the majority of cases, while in peripheral cysts a spleen-preserving surgery was feasible for most of the patients (p = 0.001). The size of the cyst was significantly higher in the group of patients with a total splenectomy, compared with the group with a partial splenectomy (p = 0.003). In the subgroup with a distributed arterial pattern, preservation of more than 50% of the initial parenchyma was achieved in a significantly higher proportion of patients, compared with the subgroup of patients with a magistral pattern (p = 0.012).

CONCLUSION

Besides cyst size or peripheral location in the splenic parenchyma, the vascular pattern is also considered another decisive factor that associates with successful conservative or minimally invasive approach.

Smoking and Risk Factors in Deep Vein Thrombosis

The incidence of deep vein thrombosis (DVT) as diagnosed by the 125I fibrinogen test (125IFT) was determined in a series of 300 newly admitted medical and 201 surgical patients. 6 medical patients died before 125IFT screening could be completed. The incidence of DVT was l4% in medical patients and 18% in surgical patients. Increasing age, a malignant condition and a past history of thromboembolism all increased the risk of DVT. Increasing levels of cigarette smoking were found to be associated with a reduced incidence of DVT. Although statistical significance was achieved at only the 10% level for this finding it is in agreement with the results from studies on patients with myocardial infarction. The protective effect of cigarette smoking was observed at all ages, and in both medical and surgical patients.

An Attempt to Build a National Prospective Electronic Database for Pancreaticoduodenectomies in Romania - Preliminary Results of the First Year Enrollment

Introduction: National databases for pancreaticoduodenectomies (PD) have contributed to better postoperative outcomes after such complex surgical procedure because the multicentre collection of data allowed more reliable analyses with quality assessment and further improvement of technical issues and perioperative management. The current practice and outcomes after PD are poorly known in Romania because there was no national database for these patients. Thus, in 2016 a national-intent electronic registry for PD was proposed for all Romanian surgical centers. The study aims to present the preliminary results of this national-intent registry for PD after one-year enrollment. Patients Methods: The database was started on October 1st, 2016. Data were prospectively collected with an electronic online form including 102 items for each patient. The registry was opened to all the Departments of Surgery from Romania performing PD, with no restriction. Results: During the first year of enrollment were collected the data of 181 patients with PD performed by 24 surgeons from four surgical centers. The age of patients was 64 years (28 - 81 years), with slightly male predominance (61.3%). Computed tomography was the main preoperative imaging investigation (84.5%). All the PDs were performed by an open approach. The Whipple technique was used in 53% of patients, and a venous resection was required in 14.3% of cases. A posterior approach PD was considered in 16.6% of patients. The stomach was used to treat the distal remnant pancreas in 50.1% of patients. The operative time was 285 min (110 - 615 min), and the estimated blood loss was 400 ml (80 - 3000 ml). The overall morbidity rate was 55.8%, with severe (i.e., grade III-IV Dindo-Clavien) morbidity rate of 10%, and 3.9% in-hospital mortality rate. The overall pancreatic fistula, delayed gastric emptying and hemorrhage rates were 19.9%, 39.8% and 15.5%. Periampullary malignancies were the main indications for PD (78.9%), with pancreatic cancer on the top (48%). Conclusions: To build a prospective electronic online database for PD in Romania appears to be a feasible project and a useful tool to know the current practice and outcomes after PD in our country. However, improvements are still required to encourage a larger number of surgical centers to introduce the data of patients with PD.

Using microRNA Networks to Understand Cancer

Human cancers are characterized by deregulated expression of multiple microRNAs (miRNAs), involved in essential pathways that confer the malignant cells their tumorigenic potential. Each miRNA can regulate hundreds of messenger RNAs (mRNAs), while various miRNAs can control the same mRNA. Additionally, many miRNAs regulate and are regulated by other species of non-coding RNAs, such as circular RNAs (circRNAs) and long non-coding RNAs (lncRNAs). For this reason, it is extremely difficult to predict, study, and analyze the precise role of a single miRNA involved in human cancer, considering the complexity of its connections. Focusing on a single miRNA molecule represents a limited approach. Additional information could come from network analysis, which has become a common tool in the biological field to better understand molecular interactions. In this review, we focus on the main types of networks (monopartite, association networks and bipartite) used for analyzing biological data related to miRNA function. We briefly present the important steps to take when generating networks, illustrating the theory with published examples and with future perspectives of how this approach can help to better select miRNAs that can be therapeutically targeted in cancer.

Circulating miRNAs in sepsis-A network under attack: An in-silico prediction of the potential existence of miRNA sponges in sepsis

Biomarkers based on the molecular mechanism of sepsis are important for timely diagnosis and treatment. A large panel of small non-coding microRNAs was reported to modulate the immune response in sepsis but have not been tested in clinical practice. Large-scale identification of microRNA networks in sepsis might reveal a new biological mechanism that can be also targeted by gene therapy. Therefore, the main objective of this study is to perform a comparison of the miRNA network between septic patients and healthy controls. We used the previously measured levels of expression of 16 different circulating human and viral microRNAs in plasma from 99 septic patients and 53 healthy controls. We used three different computational methods to find correlations between the expressions of microRNAs and to build microRNA networks for the two categories, septic patients and healthy controls. We found that the microRNA network of the septic patients is significantly less connected when compared to miRNA network of the healthy controls (21 edges vs 52 edges, P < 0.0001). We hypothesize that several microRNAs (miR-16, miR-29a, miR-146, miR-155, and miR-182) are being sponged in sepsis explaining the loss of connection in the septic patient miRNA network. This was specific for sepsis, as it did not occur in other conditions characterized by an increased inflammatory response such as in post-surgery patients. Using several target prediction instruments, we predicted potential common sponges for the miRNA network in sepsis from several signaling pathways. Understanding the dynamics of miRNA network in sepsis is useful to explain the molecular pathophysiology of sepsis and for designing therapeutic strategies that target essential components of the immune response pathways.

From mobility to crosstalk. A model of intracellular miRNAs motion may explain the RNAs interaction mechanism on the basis of target subcellular localization

MicroRNAs (miRNAs), 22 nucleotides long molecules with the function to reduce gene expression by inhibiting mRNA translation through partial complementary to one or more messenger RNA (mRNA) molecules. A single miRNA can reduce the expression levels of hundreds of genes and one mRNA can be a target for many miRNAs. Despite the study models used so far, miRNAs and mRNAs cannot be seen as acting in an isolated manner or even "in pairs". They most likely exert their complex actions through numerous overlapping interrelations. One of the models depicting interdependence of intracytoplasmic RNAs is the crosstalk model. It is based on a competition between several target mRNAs which are regulated by the same miRNA. In this paper, we will discuss the mobility mechanism of miRNAs, recently suggested by data from "single particle tracking" experiments. These data suggests that miRNA intracellular mobility may be of "intermittent active transport"(IAT) type. IAT is a mobility model composed by alternation of active transport (AT) and Brownian motion (BM). Based on a mathematical model, we concluded that, AT phase may explain the efficiency in reaching far targets and the BM phase may explain the competition. Furthermore, we suggest that the interaction between miRNAs and their targets depends on the concentration of the molecules, the affinity between the molecules and also on the intracellular localization of the molecules. Hence, the probability that a miRNA interacts with its target depends also on the distance to the target and the macromolecular crowding. Taken together, our data proposes an intracytoplasmic mobility mechanism for miRNA and shows that this model can partially explain the RNA crosstalk.

Robotically performed total mesorectal excision for rectal cancer

BACKGROUND

Rectal cancer is an important health problem, due to the increasing number of new cases and the quality of life issues brought forth by surgical treatment in these patients.

AIM

The aim of the study was to analyse the results of robotic surgery in the treatment of lower and middle rectal cancer,locations in which TME is performed.

MATERIAL AND METHOD

Patients diagnosed with and operated on for rectal cancer by the means of robotic surgery between 2008-2012 at the Fundeni Clinical Institute were retrospectively analysed.

RESULTS

A number of 117 patients with rectal cancer were operated on by robotic surgery, of which 79 (67.52%) were submitted to total mesorectal excision (TME). The most frequently performed surgery was low anterior resection, followed by rectal amputation through abdominoperineal approach.Anastomosis fistula was observed in 9 (11.39%) patients. Local recurrence was encountered in 2 (2.53%) of the robotically performed surgeries.

CONCLUSIONS

1. Robotically assisted total mesorectal excision is feasible, safe and can be performed with a small number of complications and a low local recurrence rate; 2. The main advantages are oncological safety and quality of life; 3.Conversion to open surgery is rarely encountered; 4. Protection loop ileostomy existence allows avoiding reintervention in case anastomotic fistula occurs in patients with low anterior resection. 5. Robotic surgery may become gold standard in the surgical treatment of rectal cancer.

Key principles of miRNA involvement in human diseases

Although rapid progress in our understanding of the functions of miRNA has been made by experimentation and computational approach, a considerable effort still has to be done in determining the general principles that govern the miRNA's mode of action in human diseases. We will further discuss how these principles are being progressively approached by molecular studies, as well as the importance of miRNA in regulating different target genes and functions in specific biological contexts. There is a great demand to understand the principles of context - specific miRNA target recognition in order to design future experiments and models of normal developmental and disease states.

Potentiality of the "Gum Metal" titanium-based alloy for biomedical applications

In this study, the "Gum Metal" titanium-based alloy (Ti-23Nb-0.7Ta-2Zr-1.2O) was synthesized by melting and then characterized in order to evaluate its potential for biomedical applications. Thus, the mechanical properties, the corrosion resistance in simulated body fluid and the in vitro cell response were investigated. It was shown that this alloy presents a very high strength, a low Young's modulus and a high recoverable strain by comparison with the titanium alloys currently used in medicine. On the other hand, all electrochemical and corrosion parameters exhibited more favorable values showing a nobler behavior and negligible toxicity in comparison with the commercially pure Ti taken as reference. Furthermore, the biocompatibility tests showed that this alloy induced an excellent response of MC3T3-E1 pre-osteoblasts in terms of attachment, spreading, viability, proliferation and differentiation. Consequently, the "Gum Metal" titanium-based alloy processes useful characteristics for the manufacturing of highly biocompatible medical devices.

MicroRNAs and ceRNAs: therapeutic implications of RNA networks

INTRODUCTION

A new concept of gene regulation, in which competitive endogenous RNAs (ceRNAs) compete for common microRNAs (miRNAs), suggests that mRNA targets have an active role as key elements in the regulation of miRNA availability within cells. ceRNAs are considered to be natural decoys of miRNA activity and can influence the expression of multiple miRNAs.

AREAS COVERED

A new complex network of indirect interaction among the RNA transcripts competing for the same pool of miRNAs has been described; in this network, the nodes are the targets, and the links between the nodes are the miRNAs the targets have in common, which form smaller subnetworks. The incidence, state and severity of cancer can be evaluated on the basis of this network signature. The study of these new genome-scale regulatory networks involving miRNAs and ceRNAs may provide information that researchers can use to fine-tune these networks to improve responses to cancer therapy and/or develop new therapeutic interventions.

EXPERT OPINION

Combinational approaches based on complex regulatory ceRNA networks (ceRNETs) may be one of the most promising strategies for silencing important mediators of cancer-promoting pathways. Targeting a single miRNA may in fact represent a combined intervention that acts on the feedback and compensatory pathways that can impair treatment response or cause treatment resistance.

Benign cystic neoplasm and endocrine tumours of the pancreas--when and how to operate--an overview

BACKGROUND

The recent evolution of limited local operative procedures for benign pancreatic lesions shifted surgical treatment options to the application of local techniques, although major resections of pancreatic head and left resection are still the standard.

OBJECTIVES

To evaluate the level of evidence of tumour enucleation (EN), pancreatic middle segment resection (PMSR) and duodenum preserving total/subtotal pancreatic head resection (DPPHRt/s), we focus based on present knowledge on indication to surgical treatment evaluating the questions, when and how to operate.

RESULTS

Tumour enucleation is recommended for all symptomatic neuro-endocrine tumours with size up to 2-3 cm and non-adherence to pancreatic main-ducts. EN has been applied predominantly in neuro-endocrine tumours and less frequently in cystic neoplasms. 20% of enucleation are performed as minimal invasive laparascopic procedure. Surgery related severe post-operative complications with the need of re-intervention are observed in about 11%, pancreatic fistula in 33%. The major advantage of EN are low procedure related early post-operative morbidity and a very low hospital mortality. PMSR is applied in two thirds for symptomatic cystic neoplasm and in one third for neuro-endocrine tumours. The high level of 33% pancreatic fistula and severe post-operative complications of 18% is related to management of proximal pancreatic stump. DPPHRt/s is used in 70% for symptomatic cystic neoplasms, for lesions with risk for malignancy and in less than 10% for neuro-endocrine tumours. DPPHRt with segment resection of peripapillary duodenum and intra-pancreatic common bile duct has been applied in one third of patients and in two thirds by complete preservation of duodenum and common bile duct. The level of evidence for EN and PMSR is low because of retrospective data evaluation and absence of RCT results. For DPPHR, 7 prospective, controlled studies underline the advantages compared to partial pancreaticoduodenectomy.

CONCLUSION

The application of tumour enucleation, pancreatic middle segment resection and duodenum preserving subtotal or total pancreatic head resection are associated with low level surgery related early post-operative complications and a very low hospital mortality. The major advantage of the limited procedures is preservation of exo- and endocrine pancreatic functions.

Fractal-like kinetics of intracellular enzymatic reactions: a chemical framework of endotoxin tolerance and a possible non-specific contribution of macromolecular crowding to cross-tolerance

BACKGROUND

The response to endotoxin (LPS), and subsequent signal transduction lead to the production of cytokines such as tumor necrosis factor-α (TNF-α) by innate immune cells. Cells or organisms pretreated with endotoxin enter into a transient state of hyporesponsiveness, referred to as endotoxin tolerance (ET) which represents a particular case of negative preconditioning. Despite recent progress in understanding the molecular basis of ET, there is no consensus yet on the primary mechanism responsible for ET and for the more complex cases of cross tolerance. In this study, we examined the consequences of the macromolecular crowding (MMC) and of fractal-like kinetics (FLK) of intracellular enzymatic reactions on the LPS signaling machinery. We hypothesized that this particular type of enzyme kinetics may explain the development of ET phenomenon.

METHOD

Our aim in the present study was to characterize the chemical kinetics framework in ET and determine whether fractal-like kinetics explains, at least in part, ET. We developed an ordinary differential equations (ODE) mathematical model that took into account the links between the MMC and the LPS signaling machinery leading to ET. We proposed that the intracellular fractal environment (MMC) contributes to ET and developed two mathematical models of enzyme kinetics: one based on Kopelman's fractal-like kinetics framework and the other based on Savageau's power law model.

RESULTS

Kopelman's model provides a good image of the potential influence of a fractal intracellular environment (MMC) on ET. The Savageau power law model also partially explains ET. The computer simulations supported the hypothesis that MMC and FLK may play a role in ET.

CONCLUSION

The model highlights the links between the organization of the intracellular environment, MMC and the LPS signaling machinery leading to ET. Our FLK-based model does not minimize the role of the numerous negative regulatory factors. It simply draws attention to the fact that macromolecular crowding can contribute significantly to the induction of ET by imposing geometric constrains and a particular chemical kinetic for the intracellular reactions.

Robotic surgery for rectal cancer: a single center experience of 100 consecutive cases

BACKGROUND

Minimally invasive techniques have revolutionized the field of general surgery over the few last decades. Despite its advantages, in complex procedures such as rectal surgery, laparoscopy has not achieved a high penetration rate because of its steep learning curve, its relatively high conversion rate and technical challenges. The aim of this study was to present a single center experience with robotic surgery for rectal cancer focusing mainly on early and mid-term postoperative outcome.

METHODS

A series of 100 consecutive patients who underwent robotic rectal surgery between January 2008 and June 2012 was analyzed retrospectively in terms of demographics, pathological data, surgical and oncological outcomes.

RESULTS

Seventy-seven patients underwent robotic sphincter-saving resection, and 23 patients underwent robotic abdominoperineal resection. There were 4 conversions. The median operative time for sphincter-saving procedures was 180 min. The median time for robotic abdominoperineal resection was 160 min. The median distal resection margin of the operative specimen was 3 cm. The median number of retrieved lymph nodes was 14. The median hospital stay was 10 days. In-hospital mortality was nil. The overall morbidity was 30%. Four patients presented transitory postoperative urinary dysfunction. Severe erectile dysfunction was reported by 3 patients. The median length of follow-up was 24 months. The 3-year overall survival rate was 90%.

CONCLUSIONS

Robotic surgery is advantageous for both surgeons (in that it facilitates dissection in a narrow pelvis) and patients (in that it affords a very good quality of life via the preservation of sexual and urinary function in the vast majority of patients and it has low morbidity and good midterm oncological outcomes). In rectal cancer surgery, the robotic approach is a promising alternative and is expected to overcome the low penetration rate of laparoscopy in this field.

Surface characterization and biocompatibility of titanium alloys implanted with nitrogen by Hardion+ technology

In this study, the new Hardion+ micro-implanter technology was used to modify surface properties of biomedical pure titanium (CP-Ti) and Ti-6Al-4V ELI alloy by implantation of nitrogen ions. This process is based on the use of an electron cyclotron resonance ion source to produce a multienergetic ion beam from multicharged ions. After implantation, surface analysis methods revealed the formation of titanium nitride (TiN) on the substrate surfaces. An increase in superficial hardness and a significant reduction of friction coefficient were observed for both materials when compared to non-implanted samples. Better corrosion resistance and a significant decrease in ion release rates were observed for N-implanted biomaterials due to the formation of the protective TiN layer on their surfaces. In vitro tests performed on human fetal osteoblasts indicated that the cytocompatibility of N-implanted CP-Ti and Ti-6Al-4V alloy was enhanced in comparison to that of the corresponding non treated samples. Consequently, Hardion+ implantation technique can provide titanium alloys with better qualities in terms of corrosion resistance, cell proliferation, adhesion and viability.

A clinical case of Fournier gangrene

OBJECTIVE

To present a case of Fournier gangrene and the specific surgical therapy

CASE PRESENTATION

A 71-year old patient with a two days history of pain in the perineal region, swelling, developing necrosis and foul-smelling lesions was examined in emergency settings. The swelling of subcutaneous plane involved the flank regions, mainly on the left side. The investigations were performed (full blood count, blood urea, electrolytes, coagulation profile). A Fournier gangrene was diagnosed and surgery performed under general anesthesia. Broad spectrum antibiotics were given concomitantly. The first surgical procedure consisted in surgical debridement and excision of all the necrotic tissue. Cultures were taken. We performed counter incisions bilaterally on both flanks. The communication through the fascial planes was clearly demonstrated, especially on the left side. A loop colostomy was also performed. Multiple re-excisions were further employed. Due to a precarious evolution, the patient were on mechanical ventilation for 13 days. Inotrope medication was given for a total of 19 days and, the antibiotherapy adapted to the antibiogram (Bacterioides eggerthii was identified). The reconstruction of the perineum was later performed and, after 3 months, the colostomy was closed in good conditions without further complications.

CONCLUSION

Early recognition and aggressive surgical excision are mandatory for success in patients with Fournier gangrene. Colonic diversion can be very useful if employed from the beginning.

Robotic surgery of locally advanced gastric cancer: a single-surgeon experience of 41 cases

The mainstay of curative gastric cancer treatment is open gastric resection with regional lymph node dissection. Minimally invasive surgery is yet to become an established technique with a well defined role. Robotic surgery has by-passed some of the limitations of conventional laparoscopy and has proven both safe and feasible. We present our initial experience with robotic surgery based on 41 gastric cancer patients. We especially wish to underline the advantages of the robotic system when performing the digestive tract anastomoses. We present the techniques of end-to-side eso-jejunoanastomoses (using a circular stapler or manual suture) and side-to-side eso-jejunoanastomoses. In our hands, the results with circular stapled anastomoses were good and we advocate against manual suturing when performing anastomoses in robotic surgery. Moreover, we recommend performing totally intracorporeal anastomoses which have a better post-operative outcome, especially in obese patients. We present three methods of realising the total intracorporeal eso-jejuno-anastomosis with a circular stapler: manual purse-string suture, using the OrVil and the double stapling technique. The eso-jejunoanastomosis is one of the most difficult steps in performing the total gastrectomy, but these techniques allow the surgeon to choose the best option for each case. We consider that surgeons who undertake total gastrectomies must have a special training in performing these anastomoses.