Potential therapeutic targets discovery by transcriptome analysis of an in vitro human gastric signet ring carcinoma model.

BACKGROUND: Loss of E-cadherin expression is frequently observed in signet ring carcinoma (SRCC). People with germline mutations in CDH1, which encodes E-cadherin, develop diffuse gastric cancer at a higher rate. Loss of E-cadherin expression is thus assumed to trigger oncogenic development. METHODS: To investigate novel therapeutic targets for gastric SRCC, we engineered an E-cadherin-deficient SRCC model in vitro using a human gastric organoid (hGO) with CDH1 knockout (KO). RESULTS: CDH1 KO hGO cells demonstrated distinctive morphological changes similar to SRCC and high cell motility. RNA-sequencing revealed up-regulation of matrix metalloproteinase (MMP) genes in CDH1 KO hGO cells compared to wild type. MMP inhibitors suppressed cell motility of CDH1 KO hGO cells and SRCC cell lines in vitro. Immunofluorescent analysis with 95 clinical gastric cancer tissues revealed that MMP-3 was specifically abundant in E-cadherin-aberrant SRCC. In addition, CXCR4 molecules translocated onto the cell membrane after CDH1 KO. Addition of CXCL12, a ligand of CXCR4, to the culture medium prolonged cell survival of CDH1 KO hGO cells and was abolished by the inhibitor, AMD3100. In clinical SRCC samples, CXCL12-secreting fibroblasts showed marked infiltration into the cancer area. CONCLUSIONS: E-cadherin deficient SRCCs might gain cell motility through upregulation of MMPs. CXCL12-positive cancer-associated fibroblasts could serve to maintain cancer-cell survival as a niche. MMPs and the CXCL12/CXCR4 axis represent promising candidates as novel therapeutic targets for E-cadherin-deficient SRCC.

Histidine-Rich Glycoprotein Alleviates Liver Ischemia/Reperfusion Injury in Mice With Nonalcoholic Steatohepatitis.

Hepatic ischemia/reperfusion injury (IRI) is a major complication of liver surgery and transplantation, especially in patients with nonalcoholic steatohepatitis (NASH). The mechanism of NASH susceptibility to IRI has not been fully clarified. We investigated the role of liver-produced histidine-rich glycoprotein (HRG) in NASH IRI. A NASH mouse model was established using C57BL/6J mice fed a methionine-choline-deficient diet (MCDD) for 6 weeks. The MCDD and standard diet groups were exposed to 60 minutes of partial hepatic ischemia/reperfusion (I/R). We further evaluated the impact of HRG in this context using HRG knockdown (KD) mice. IRI increased HRG expression in the standard diet group, but not in the MCDD group after I/R. HRG expression was inversely correlated with neutrophil infiltration and the formation of neutrophil extracellular traps (NETs). HRG KD mice showed severe liver injury with neutrophil infiltration and the formation of NETs. Pretreatment with supplementary HRG protected against I/R with the inhibition of neutrophil infiltration and the formation of NETs. In vitro, hepatocytes showed that the expression of HRG was upregulated under hypoxia/reoxygenation conditions, but not in response to oleic acid-treated hepatocytes. The decrease in HRG expression in fatty hepatocytes was accompanied by decreased farnesoid X receptor and hypoxia inducible factor 2 alpha subunit expression. HRG is a hepatoprotective factor during hepatic IRI because it decreases neutrophil infiltration and the formation of NETs. The decrease in HRG is a cause of susceptibility to IRI in steatotic livers. Therefore, HRG is a new therapeutic target for minimizing liver damage in patients with NASH.

Surgical Navigation Improves Renal Parenchyma Volume Preservation in Robot-Assisted Partial Nephrectomy: A Propensity Score Matched Comparative Analysis.

PURPOSE: We investigated the relationship between the surgical navigation system and postoperative parenchyma preservation volume, and assessed the feasibility of image guided surgery in robot-assisted partial nephrectomy. MATERIALS AND METHODS: We developed surgical navigation with registration between real-time endoscopic images using 3-dimensional virtual reality models for robot-assisted partial nephrectomy. Surgical outcomes of 44 (nonsurgical navigation group) and 102 (surgical navigation group) patients between June 2013 and December 2018 were retrospectively analyzed. To adjust for potential baseline confounders propensity score matching (1:1) was performed. Renal parenchymal preservation rate and extraparenchymal volume with a tumor including functional and oncological outcomes ("trifecta" defined as warm ischemia time of less than 25 minutes, no complications and negative surgical margins; "pentafecta" defined as trifecta plus greater than 90% preservation of estimated glomerular filtration rate at 12 months postoperatively and chronic kidney disease up staging) were evaluated using volumetric analysis and compared. RESULTS: After matching, 42 patients were allocated to each group. No significant differences in baseline characteristics; complications; and intraoperative, trifecta and pentafecta outcomes were observed between the 2 groups. Pathological T stages were significantly different between the groups (T1a/T1b/T2a or more 25/10/7 in the nonsurgical navigation group vs 35/7/0 in the surgical navigation group, p=0.003). Extraparenchymal volumes and parenchyma volume preservation rates were significantly higher in the surgical navigation group (21.4 vs 17.2 ml, p=0.041 and 83.5% vs 90.0%, p=0.042, respectively). Surgical navigation was positively associated with improved parenchyma preservation volume (p=0.003). CONCLUSIONS: Surgical navigation preserves renal parenchyma in robot-assisted partial nephrectomy and may contribute to improvement in postoperative renal function.

Adipose tissue-derived stromal cells are sources of cancer-associated fibroblasts and enhance tumor progression by dense collagen matrix.

Although recent studies revealed that adipose tissue accelerates pancreatic tumor progression with excessive extracellular matrix, key players for desmoplasia in the adipose microenvironment remains unknown. Here, we investigated the roles of adipose tissue-derived stromal cells (ASCs) in desmoplastic lesions and tumor progression by in vitro and in vivo experiments. In a three-dimensional (3-D) organotypic fat invasion model using visceral fat from CAG-EGFP mice, GFP-positive fibroblastic cells infiltrated toward cancer cells. When tumor cells were inoculated into transplanted visceral fat pads in vivo, tumor weights and stromal components were enhanced compared to subcutaneous and orthotopic tumor cells inoculated without fat pads. Expression of αSMA in established human ASCs was lower compared to cancer associated fibroblasts, and the 3-D collagen matrices produced by ASCs cultured in cancer cell-conditioned medium changed from loose to dense structures that affected the motility of cancer cells. Microarray analyses revealed upregulation of S100A4 in ASCs, while S100A4-positive stromal cells were observed at extrapancreatic invasion sites of human pancreatic cancer. The present findings indicate that ASCs are recruited to extrapancreatic invasion sites and produce dense collagen matrices that lead to enhanced tumor progression. Both inhibition of ASCs recruitment and activation could lead to a novel antistromal therapy.

Efficacy of Novel Multispectral Imaging Device to Determine Anastomosis for Esophagogastrostomy.

BACKGROUND: Biomedical imaging devices that utilize the optical characteristics of hemoglobin (Hb) have become widespread. In the field of gastroenterology, there is a strong demand for devices that can apply this technique to surgical navigation. We aimed to introduce our novel multispectral device capable of intraoperatively performing quantitative imaging of the oxygen (O2) saturation and Hb amount of tissues noninvasively and in real time, and to examine its application for deciding the appropriate anastomosis point after subtotal or total esophagectomy. MATERIALS AND METHODS: A total of 39 patients with esophageal cancer were studied. Tissue O2 saturation and Hb amount of the gastric tube just before esophagogastric anastomosis were evaluated using a multispectral tissue quantitative imaging device. The anastomosis point was decided depending on the quantitative values and patterns of both the tissue O2 saturation and Hb amount. RESULTS: The device can instantaneously and noninvasively quantify and visualize the tissue O2 saturation and Hb amount using reflected light. The tissue Hb status could be classified into the following four types: good circulation type, congestion type, ischemia type, and mixed type of congestion and ischemia. Postoperative anastomotic failure occurred in 2 cases, and both were mixed cases. CONCLUSIONS: The method of quantitatively imaging the tissue O2 saturation and Hb level in real time and noninvasively using a multispectral device allows instantaneous determination of the anastomosis and related organ conditions, thereby contributing to determining the appropriate treatment direction.

Japanese periodical nationwide epidemiologic survey of aberrant portal hemodynamics.

AIM: Idiopathic portal hypertension (IPH), extrahepatic portal obstruction (EHO), and Budd-Chiari syndrome (BCS) are characterized by aberrant portal hemodynamics of unknown etiology. The aim of this study was to explore trends in the descriptive epidemiology of these diseases through periodical nationwide surveys. METHODS: Nationwide epidemiologic surveys were undertaken in 1999, 2005, and 2015 using the same protocol. The survey targets were selected from all departments of gastrointestinal medicine, surgery, pediatrics, and pediatric surgery in Japan by stratified random sampling according to the number of beds. We asked each department to complete a mail-back questionnaire on the annual numbers of patients with IPH, EHO, and BCS during the preceding year. RESULTS: The estimated number of BCS patients increased from 280 (95% confidence interval, 200-360) in 1999 survey to 410 (300-530) in 2015 survey, whereas the number of IPH and EHO patients has remained largely unchanged during the 15 years (IPH was approximately 1000; EHO was approximately 770 in 2015 survey). The mean age at symptom onset was approximately 45 years for IPH, 30 years for EHO, and 40 years for BCS over the past 15 years. Those who described disease aggravation from the time of diagnosis accounted for approximately 10% of IPH, 15% of EHO, and 20% of BCS patients in each of the three surveys. CONCLUSIONS: In Japan, the prevalence of BCS is increasing, while those of IPH and EHO appear to be stable. Clinical characteristics, including prognoses, have remained largely unchanged in the past 15 years.

Colorectal endoscopic submucosal dissection using novel articulating devices: a comparative study in a live porcine model.

BACKGROUND AND AIMS: Colonic endoscopic submucosal dissection (ESD) is time-consuming and bears a high risk of perforation. The aim of the present study was to compare the safety and efficacy between novel articulating devices and conventional ESD in live porcine colon models. METHODS: Thirty ESDs in ten pigs were carried out at three different locations (15, 25, and 35 cm from the anus) by the conventional method (n = 15) and by the new method (n = 15). Procedure times, adverse events (perforation, bleeding), and damage to the muscular layer were recorded, and the ESD time per unit area of the specimens was calculated. RESULTS: The perforation rate using the conventional method was 6.7% (1/15), whereas that using the new method was 0.0%. The number of sites of muscular damage was significantly lower in the new than conventional method (6 vs. 37, respectively; P = 0.024). The mean procedure time was significantly shorter in the new than conventional method (4.6 ± 2.0 vs. 7.0 ± 4.1 min/cm2, respectively; P = 0.042). CONCLUSIONS: Use of the new ESD method allows for reduced adverse events and a shortened resection time.

Autophagy Is Required for Activation of Pancreatic Stellate Cells, Associated With Pancreatic Cancer Progression and Promotes Growth of Pancreatic Tumors in Mice.

BACKGROUND & AIMS: Pancreatic stellate cells (PSCs) change from a quiescent to activated state in the tumor environment and secrete extracellular matrix (ECM) molecules and cytokines to increase the aggressiveness of tumors. However, it is not clear how PSCs are activated to produce these factors, or whether this process can be inhibited. PSCs have morphologic and functional similarities to hepatic stellate cells, which undergo autophagy to promote fibrosis and tumor growth. We investigated whether autophagy activates PSCs, which promotes development of the tumor stroma and growth of pancreatic tumors in mice. METHODS: We used immunofluorescence microscopy and immunohistochemistry to analyze pancreatic tumor specimens from 133 patients who underwent pancreatectomy in Japan from 2000 to 2009. PSCs were cultured from pancreatic tumor tissues or tissues of patients with chronic pancreatitis; these were analyzed by immunofluorescence microscopy, immunoblots, quantitative reverse transcription polymerase chain reaction, and in assays for invasiveness, proliferation, and lipid droplets. Autophagy was inhibited in PSCs by administration of chloroquine or transfection with small interfering RNAs. Proteins were knocked down in immortalized PSCs by expression of small hairpin RNAs. Cells were transplanted into pancreatic tails of nude mice, and tumor growth and metastasis were quantified. RESULTS: Based on immunohistochemical analyses, autophagy was significantly associated with tumor T category (P = .018), histologic grade (P = .001), lymph node metastases (P < .001), stage (P = .009), perilymphatic invasion (P = .001), and perivascular invasion (P = .003). Autophagy of PSCs was associated with shorter survival times of patients with pancreatic cancer. PSC expression of microtubule-associated protein 1 light chain 3, a marker of autophagosomes, was associated with poor outcomes (shorter survival time, disease recurrence) for patients with pancreatic cancer (relative risk of shorter survival time, 1.56). Immunoblots showed that PSCs from pancreatic tumor samples expressed higher levels of markers of autophagy than PSCs from chronic pancreatitis samples. Inhibitors of autophagy increased the number of lipid droplets of PSCs, indicating a quiescent state of PSCs, and reduced their production of ECM molecules and interleukin 6, as well as their proliferation and invasiveness in culture. PSCs exposed to autophagy inhibitors formed smaller tumors in nude mice (P = .001) and fewer liver metastases (P = .018) with less peritoneal dissemination (P = .018) compared to PSCs not exposed to autophagy inhibitors. CONCLUSIONS: Autophagic PSCs produce ECM molecules and interleukin 6 and are associated with shorter survival times and disease recurrence in patients with pancreatic cancer. Inhibitors of PSC autophagy might reduce pancreatic tumor invasiveness by altering the tumor stroma.

A novel histological examination with dynamic three-dimensional reconstruction from multiple immunohistochemically stained sections of a PD-L1-positive colon cancer.

AIMS: Programmed cell death-ligand 1 (PD-L1) expression is observed in patients with microsatellite instability-high (MSI-H) colon cancer, which is susceptible to immune checkpoint blockade. The aim of this study was to investigate the interrelationship between PD-L1-positive cells and cytotoxic T cells, lymphatic vessels and vascular endothelium by using histological examination with the three-dimensional (3D) reconstruction of a PD-L1-positive colon cancer. METHODS AND RESULTS: Serial sections of MSI-H colon cancer tissue were stained with haematoxylin and eosin (H&E) and Masson trichrome stains; immunohistochemical analysis of PD-L1, CD8, D2-40 and CD31 was performed. Several 3D models of MSI-H colon cancer were reconstructed with a 3D data visualisation system. Moreover, 18 serial sections were stained with PD-L1, cytokeratin AE1/AE3, CD45, CD31, CD68 and H&E in the same case to confirm that PD-L1 was expressed on tumour cells, CD31-positive cells and macrophages in the invasive frontal region. Notably, there was a peak in the expression of PD-L1 and CD31 in the invasive frontal region. D2-40-positive cells were abundant in the overall tumour stroma, and CD8-positive cells infiltrated the tumour parenchyma. PD-L1 was expressed on tumour cells in the parenchyma and other cells in the stroma. Additional staining of 18 consecutive sections revealed that the other cells were CD68-positive and CD45-positive macrophages and CD31-positive proliferating vascular endothelial cells. CONCLUSIONS: We confirmed that PD-L1 was highly expressed in the invasive frontal region in 3D models of MSI-H colon cancer tissue. This method can be useful for accurately evaluating the localisation of immune checkpoint molecules.

A new robotic-assisted flexible endoscope with single-hand control: endoscopic submucosal dissection in the ex vivo porcine stomach.

BACKGROUND: Difficulties in endoscopic operations and therapeutic procedures seem to occur due to the complexity of operating the endoscope dial as well as difficulty in performing synchronized movements with both hands. We developed a prototype robotic-assisted flexible endoscope that can be controlled with a single hand in order to simplify the operation of the endoscope. The aim of this study was to confirm the operability of the robotic-assisted flexible endoscope (RAFE) by performing endoscopic submucosal dissection (ESD). METHODS: Study 1: ESD was performed manually or with RAFE by an expert endoscopist in ex vivo porcine stomachs; six operations manually and six were performed with RAFE. The procedure time per unit circumferential length/area was calculated, and the results were statistically analyzed. Study 2: We evaluated how smoothly a non-endoscopist can move a RAFE compared to a manual endoscope by assessing the designated movement of the endoscope. RESULTS: Study 1: En bloc resection was achieved by ESD using the RAFE. The procedure time was gradually shortened with increasing experience, and the procedure time of ESD performed with the RAFE was not significantly different from that of ESD performed with a manual endoscope. Study 2: The time for the designated movement of the endoscope was significantly shorter with a RAFE than that with a manual endoscope as for a non-endoscopist. CONCLUSIONS: The RAFE that we developed enabled an expert endoscopist to perform the ESD procedure without any problems and allowed a non-endoscopist to control the endoscope more easily and quickly than a manual endoscope. The RAFE is expected to undergo further development.

A new innovative laparoscopic fundoplication training simulator with a surgical skill validation system.

PURPOSE: We developed and validated a specific laparoscopic fundoplication simulator for use with the objective endoscopic surgical skills evaluation system. The aim of this study was to verify the quality of skills of surgeons. MATERIALS AND METHODS: We developed a 1-year-old infant body model based on computed tomography data and reproduced pneumoperitoneum model based on the clinical situation. The examinees were divided into three groups: fifteen pediatric surgery experts (PSE), twenty-four pediatric surgery trainees (PSN), and ten general surgeons (GS). They each had to perform three sutures ligatures for construction of Nissen wrap. Evaluate points are time for task, the symmetry of the placement of the sutures, and the uniformity of the interval of suture ligatures in making wrap. And the total path length and velocity of forceps were measured to assess bi-hand coordination. RESULTS: PSE were significantly superior to PSN regarding total time spent (p < 0.01) and total path length (p < 0.01). GS used both forceps faster than the other groups, and PSN used the right forceps faster than the left forceps (p < 0.05). PSE were shorter with regard to the total path length than GS (p < 0.01). PSE showed most excellent results in the symmetry of the wrap among three groups. CONCLUSION: Our new model was used useful to validate the characteristics between GS and pediatric surgeon. Both PSE and GS have excellent bi-hand coordination and can manipulate both forceps equally and had superior skills compared to PSN. In addition, PSE performed most compact and accurate skills in the conflicted operative space.

Improving the strength of sutureless laser-assisted vessel repair using preloaded longitudinal compression on tissue edge.

BACKGROUND AND OBJECTIVE: Little is known about the approximation of coapted edges in sutureless laser-assisted vessel welding. Tissue shrinkage by laser irradiation may cause coapted edges to separate, reducing strength of welding. This may be avoided by preloaded longitudinal compression on the tissue edges to be welded. This study compared welding strength with and without preloaded compression in ex vivo animal experiments. MATERIALS AND METHODS: This study evaluated 24 samples of harvested porcine carotid arteries, each having a length of 3 cm and an inner diameter of 1.0-2.0 mm. A half circumferential incision was made at the center of each sample. A steel shaft 2.0 mm in diameter was inserted into each sample to approximate the incised edges. The samples were longitudinally compressed to 6 mm. Incision sites were repaired by irradiation with a 970-nm diode laser. No glue or die was used. The repair strength was evaluated by measuring the bursting point (BP) of all samples. In a pilot study, the welding conditions, including power, duration, and interval of the laser spots, were tested by trial and error in 18 samples, including six treated under optimum conditions. As a control group, six samples were welded under optimum conditions, but without compression. RESULTS: Optimum conditions, consisting of 2.4 W power, 30-second duration, and 1-mm intervals of laser spots, yielded the highest BP (623 ± 236 mmHg), which was significantly higher than in the control group without compression (204 ± 208 mmHg, P = 0.009). Defining BP > 400 mmHg as successful repair, the success rates in the compression and control groups were 83% and 17%, respectively. CONCLUSION: Preloaded longitudinal compression on the coapted edges may be important for sutureless laser-assisted vessel repair and anastomosis and may affect the strength of welding. Lasers Surg. Med. 49:533-538, 2017. © 2017 Wiley Periodicals, Inc.

Novel imaging using a touchless display for computer-assisted hepato-biliary surgery.

PURPOSE: We developed a touchless display system that allows the user to control the medical imaging software via hand gestures in the air. We conducted this study to verify the effectiveness of this novel touchless display system as a tool for assisting with surgical imaging. METHODS: The patient's computed tomography (CT) data are generally observed on a display during surgery. The "Dr. aeroTAP" touchless display system was developed to generate virtual mouse events based on the position of one hand. We conducted comparative analyses of using the Dr. aeroTAP vs. using a regular mouse (control group) by measuring the time to select a 3D image from 24 thumbnail images on a screen (study 1) and to then see the CT image on the DICOM viewer (study 2). RESULTS: We used the Dr. aeroTAP in 31 hepato-biliary operative procedures performed at our hospital. In study 1, which measured the time required to select one of 24 thumbnails, there were significant differences between the mouse and Dr. aeroTAP groups for all five surgeons who participated (P < 0.001). In study 2, there were also significant differences in the time required for CT DICOM images to be displayed (P < 0.001). CONCLUSIONS: The touchless interface proved efficient for allowing the observation of surgical images while maintaining a sterile field during surgery.

CD146 attenuation in cancer-associated fibroblasts promotes pancreatic cancer progression.

Cancer-associated fibroblasts (CAFs) are heterogeneous cell populations that influence tumor initiation and progression. CD146 is a cell membrane protein whose expression has been implicated in multiple human cancers. CD146 expression is also detected in pancreatic cancer stroma; however, the role it plays in this context remains unclear. This study aimed to clarify the function and significance of CD146 expression in pancreatic cancer. We performed immunohistochemical staining to investigate the prevalence of CD146 expression in stromal fibroblasts in pancreatic cancer. We also examined the influence of CD146 on CAF-mediated tumor invasion and migration and CAF activation using CD146 small interfering RNA or overexpression plasmids in primary cultures of CAFs derived from pancreatic cancer tissues. CD146 expression in CAFs was associated with high-grade pancreatic intraepithelial neoplasia and low histological grade invasive ductal carcinoma of the pancreas, while patients with low CD146 expression had a poorer prognosis. Blocking CD146 expression in CAFs significantly enhanced tumor cell migration and invasion in a co-culture system. CD146 knockdown also promoted CAF activation, possibly by inducing the production of pro-tumorigenic factors through modulation of NF-κB activity. Consistently, overexpression of CD146 in CAFs inhibited migration and invasion of co-cultured cancer cells. Finally, CD146 expression in CAFs was reduced by interaction with cancer cells. Our findings suggest that decreased CD146 expression in CAFs promotes pancreatic cancer progression. © 2015 Wiley Periodicals, Inc.

Splenectomy enhances the therapeutic effect of adipose tissue-derived mesenchymal stem cell infusion on cirrhosis rats.

BACKGROUND & AIMS: Clinical studies suggest that splenectomy improves liver function in cirrhotic patients, but the influence of splenectomy on stem cell transplantation is poorly understood. This study investigated the effect of splenectomy on stem cell infusion and elucidated its mechanism. METHODS: Rat adipose tissue-derived mesenchymal stem cells were infused into cirrhosis rats with or without splenectomy, followed by the assessment of the in vivo distribution of stem cells and pathological changes. Stromal cell-derived factor-1 and hepatocyte growth factor expression were also investigated in splenectomized cirrhosis patients and rats. RESULTS: Splenectomy, prior to cell infusion, improved liver function and suppressed fibrosis progression more efficiently than cell infusion alone in the experimental cirrhosis model. Stromal cell-derived factor-1 and hepatocyte growth factor levels after splenectomy were increased in patients and rats. These upregulated cytokines significantly facilitated stem cell motility, migration and proliferation in vitro. C-X-C chemokine receptor type 4 neutralization weakened the promotion of cell migration by these cytokines. The infused cells integrated into liver fibrosis septa and participated in regeneration more efficiently in splenectomized rats. Direct coculture with stem cells led to inhibition of hepatic stellate cell proliferation. In addition, hepatocyte growth factor induced hepatic stellate cell apoptosis via the c-jun N-terminal kinase-p53 pathway. CONCLUSIONS: Splenectomy prior to cell infusion enhanced the therapeutic effect of stem cells on cirrhosis, which involved upregulation of stromal cell-derived factor-1 and hepatocyte growth factor after splenectomy.

Evaluation of the 10-year history of a 2-day standardized laparoscopic surgical skills training program at Kyushu University.

PURPOSE: Laparoscopic and open surgical skills differ distinctly from one another. Our institute provides laparoscopic surgical skills training for currently active surgeons throughout Japan. This study was performed to evaluate the effectiveness of our 2-day standardized laparoscopic surgical skills training program over its 10-year history. METHODS: We analyzed the data on trainee characteristics, outcomes of skills assessments at the beginning and end of the program, and self-assessment after 6 months using a questionnaire survey. RESULTS: From January 2004 to December 2013, 914 surgeons completed the 2-day training program. Peaks in postgraduate years of experience occurred at years 2, 8, and 17. Suturing and knot tying times were significantly shorter at the end than beginning of the program (p < 0.001). However, the numbers of misplaced and loose sutures, maximum misplacement distance, and number of injuries to the rubber sheet were significantly higher at the end of the program (p < 0.001). A questionnaire at 6 months post-training revealed significant improvements in the overall skills and forceps manipulation (p < 0.0001) and a significantly shorter mean operation time for laparoscopic cholecystectomy (p < 0.001). CONCLUSION: Our 2-day training program for active Japanese surgeons is thus considered to be effective; however, continued voluntary training is important and further outcomes assessments are needed.

Preoperative simulation regarding the appropriate port location for laparoscopic hepaticojejunostomy: a randomized study using a disease-specific training simulator.

PURPOSE: We verified the appropriate port location for laparoscopic hepaticojejunostomy using a comprehensive laparoscopic training simulator. METHODS: We developed a hepaticojejunostomy model, consist of common hepatic duct and intestine and participants required to place two sutures precisely using two different port locations (A: standard port location, B: modified port location). The order of tasks was randomly determined using the permuted block method (Group I: Task A â†’ Task B, Group II: Task B â†’ Task A). The time for task completion and total number of errors were recorded. In addition, we evaluated the spatial paths and velocity of both forceps. Statistical analyses were performed using a statistical software program. RESULTS: The time for the task, the total error score, and the spatial paths and velocity of both forceps were not significantly different between groups I and II. Furthermore, the port location and order of tasks (group I or group II) did not significantly affect the results. In contrast, there were significant differences in the performance between experts and novices, who were classified as such based on the total number of experienced endoscopic surgeries. CONCLUSION: Preoperative port simulation in advanced surgery using our artificial simulator is feasible and may facilitate minimally invasive surgery for children.

Design and Function of Engineered Protein Nanocages as a Drug Delivery System for Targeting Pancreatic Cancer Cells via Neuropilin-1.

We describe the development of neuropilin 1-binding peptide (iRGD)-nanocages that specifically target human pancreatic cancer cells in which an iRGD is joined to the surface of naturally occurring heat shock protein (HSP) cages. Using a genetic engineering approach, the iRGD domain was joined to the C-terminal region of the HSP cage using flexible linker moieties. The characteristics of the interdomain linkages between the nanocage and the iRGD domain play an important role in the specificity and affinity of the iRGD-nanocages for their target cells. An engineered L30-iRGD-nanocage with 30 amino acid linkers, (GGS)10, showed greater binding affinity for pancreatic cancer cells relative to that of other linkers. Furthermore, a moderately hydrophobic anticancer drug, OSU03012, was successfully incorporated into the L30-iRGD-nanocage by heating the mixture. The OSU03012-loaded L30-iRGD-nanocage induced cell death of pancreatic cancer cells by activating the caspase cascade more effectively than the same concentrations of free OSU03012. The iRGD-nanocages show great potential as a novel nanocarrier for pancreatic cancer-targeted drug delivery.

Gastric endoscopic submucosal dissection using novel 2.6-mm articulating devices: an ex vivo comparative and in vivo feasibility study.

BACKGROUND AND STUDY AIMS: The conventional procedure of endoscopic submucosal dissection (ESD) is technically demanding. This study investigated the efficiency of novel articulating devices (maximum diameter 2.6 mm), which can be used with commercially available, standard endoscopes. PATIENTS AND METHODS: In an ex vivo comparative study, eight endoscopists were divided into novices and experienced operators, and performed ESD using new devices and the conventional setup. An in vivo animal experiment was performed by two experts. Procedure times for incision and dissection were recorded, and unit times for circumferential length and area of specimens were calculated. RESULTS: All procedures were successfully completed with en bloc resection. In the ex vivo study, the unit procedure times for incision and dissection by novices were significantly shorter using the new system (P < 0.01 and P < 0.05), whereas there was no significant difference for experienced endoscopists. Perforation occurred during one procedure in which the new system was used. The in vivo experiments were successfully completed without adverse events. CONCLUSIONS: ESD using novel articulating devices was feasible. These devices were able to reduce the procedure time for novices.