Feasibility and Safety of 5G-Based Telerobotic Abdominal Ultrasonography.

OBJECTIVE: Telemedicine can offer services to remote patients regardless of the distance. Fifth-generation (5G) mobile networks may make telemedicine practical because of their low latency. This study aimed to evaluate the feasibility and safety of a novel 5G robot-assisted remote abdominal ultrasound (AUS) telemedicine technology in clinical applications in distant locations. METHODS: We performed 5G-based telerobotic AUS in patients who were located more than 100 km away from the physicians. RESULTS: The telerobotic AUS had a longer examination time than the conditional bedside AUS; however, the complete examination rate was not inferior. None of the volunteers experienced discomfort during the examination and the examination time was acceptable for all. CONCLUSION: Our findings confirm the feasibility and safety of 5G-based telerobotic AUS in clinical practice.

Update on Imaging-based Noninvasive Methods for Assessing Hepatic Steatosis in Nonalcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD), among the most common chronic liver diseases worldwide, affects approximately 25% of the global population. Its incidence is increasing owing to various risk factors, including genetic variation, metabolic health, dietary habits, and microbiota. Hepatic steatosis is a critical histological characteristic of NAFLD. Evaluating liver fat content is vital for identifying and following up with patients at risk of developing NAFLD. NAFLD includes simple liver steatosis and more severe forms such as inflammation, nonalcoholic steatohepatitis, fibrosis, and cirrhosis. The early assessment of fatty liver is important for reversing liver disease progression. Metabolic (dysfunction)-associated fatty liver disease recently replaced NAFLD as the most common hepatic disease worldwide. This article reviews the current state of noninvasive imaging, especially ultrasound, for liver fat quantification.

Characterization of Mammary Tumors Arising from MMTV-PyVT Transgenic Mice.

Among genetically engineered mouse models of breast cancer, MMTV-PyVT is a mouse strain in which the oncogenic polyoma virus middle T antigen is driven by the mouse mammary tumor virus promoter. The aim of the present study was to perform morphologic and genetic analyses of mammary tumors arising from MMTV-PyVT mice. To this end, mammary tumors were obtained at 6, 9, 12, and 16 weeks of age for histology and whole-mount analyses. We conducted whole-exome sequencing to identify constitutional and tumor-specific mutations, and genetic variants were identified using the GRCm38/mm10 mouse reference genome. Using hematoxylin and eosin analysis and whole-mount carmine alum staining, we demonstrated the progressive proliferation and invasion of mammary tumors. Frameshift insertions/deletions (indels) were noted in the Muc4. Mammary tumors showed small indels and nonsynonymous single-nucleotide variants but no somatic structural alterations or copy number variations. In summary, we validated MMTV-PyVT transgenic mice as a multistage model for mammary carcinoma development and progression. Our characterization may be used as a reference for guidance in future research.

Fall Recognition Based on an IMU Wearable Device and Fall Verification through a Smart Speaker and the IoT.

A fall is one of the most devastating events that aging people can experience. Fall-related physical injuries, hospital admission, or even mortality among the elderly are all critical health issues. As the population continues to age worldwide, there is an imperative need to develop fall detection systems. We propose a system for the recognition and verification of falls based on a chest-worn wearable device, which can be used for elderly health institutions or home care. The wearable device utilizes a built-in three-axis accelerometer and gyroscope in the nine-axis inertial sensor to determine the user's postures, such as standing, sitting, and lying down. The resultant force was obtained by calculation with three-axis acceleration. Integration of three-axis acceleration and a three-axis gyroscope can obtain a pitch angle through the gradient descent algorithm. The height value was converted from a barometer. Integration of the pitch angle with the height value can determine the behavior state including sitting down, standing up, walking, lying down, and falling. In our study, we can clearly determine the direction of the fall. Acceleration changes during the fall can determine the force of the impact. Furthermore, with the IoT (Internet of Things) and smart speakers, we can verify whether the user has fallen by asking from smart speakers. In this study, posture determination is operated directly on the wearable device through the state machine. The ability to recognize and report a fall event in real-time can help to lessen the response time of a caregiver. The family members or care provider monitor, in real-time, the user's current posture via a mobile device app or internet webpage. All collected data supports subsequent medical evaluation and further intervention.

Intestinal Ultrasound in Inflammatory Bowel Disease: A Novel and Increasingly Important Tool.

New and efficacious medical therapies have become available that have greatly enhanced clinicians' ability to manage inflammatory bowel diseases (IBDs). IBD activity should be assessed regularly in scheduled examinations as the part of a treat-to-target strategy for IBD care. The gold-standard approach to investigating IBD is colonoscopy, but this is an invasive procedure. Intestinal ultrasound (IUS) has played a crucial role in recent years regarding the assessment of IBD activity because it is noninvasive, safe, reproducible, and inexpensive. IUS findings could inform changes in therapeutic interventions for IBDs; this would necessitate fewer endoscopies and enable faster decision-making processes. Furthermore, patients are accepting and tolerant of IUS examinations. This review outlines the current evidence and gives indication regarding the use of IUS in the management of IBDs.

Is contrast-enhanced endoscopic ultrasound-guided fine needle biopsy better than conventional fine needle biopsy? A retrospective study in a medical center.

BACKGROUND: Contrast-enhanced endoscopic ultrasound-guided fine needle aspiration (CE-EUS-FNA) could help clinicians to precisely locate and puncture lesions, but its effect on the diagnostic yield improvement is controversial. We designed this study to observe the additional benefit of using contrast in EUS-guided tissue sampling while performing fine needle biopsy (FNB) instead of FNA, as FNB results in a higher diagnostic accuracy. METHOD: Patients who underwent EUS-FNB performed by a single medical team from January 2019 to March 2021 were included in this study. We analyzed the cytopathological diagnostic accuracy rate and number of needle passes between groups who underwent FNB with and without contrast. RESULT: We divided 133 patients who were diagnosed with a malignancy into two groups according to whether they underwent CE-EUS-FNB (n = 48) or conventional EUS-FNB (n = 85). The CE-EUS-FNB group had an equal diagnostic accuracy rate with fewer needle passes compared with the conventional EUS-FNB group. There was no significant trend change in the success cytopathological diagnostic rate for experienced endoscopists for EUS-FNA. CONCLUSION: CE-EUS-FNB had fewer needle passes but no additional benefit for diagnostic yield improvement. There was no difficult threshold for CE-EUS-FNB for endoscopists who were well trained in conventional FNA.

Clinical efficacy and safety of peroral endoscopic myotomy for esophageal achalasia: A multicenter study in Taiwan.

BACKGROUND/OBJECTIVE: Peroral endoscopic myotomy (POEM), a novel minimally invasive treatment for esophageal achalasia, is becoming more popular globally because of its efficacy and safety. We aimed to clarify the technical concerns, efficacy, and safety of POEM for treating esophageal achalasia in Taiwan. METHODS: We conducted a retrospective study on consecutive patients with achalasia who underwent POEM between October 2016 and May 2021 at three medical centers in Taiwan. All patients underwent a comprehensive work-up before POEM, including symptom questionnaires, esophagogastroduodenoscopy, timed barium esophagogram (TBE), and high-resolution impedance manometry (HRIM), and were re-evaluated three months after POEM. We compared procedure variables, adverse events, and clinical responses, including Eckardt score ≤3 and TBE and HRIM findings. RESULTS: We analyzed 92 patients in total (54 men; mean age 49.5 years [range: 20-87]; type I/II/III/unclassified: 24/51/1/16). The mean POEM procedure duration was 89.5 ± 38.2 min, though it was significantly longer in patients with prior treatment or sigmoid-type achalasia. In total, 91 patients (98.9%) showed immediate technical success, and the overall clinical success rate at three months after POEM was 95.7%. Nearly 60% of patients experienced adverse events during POEM, but most of these were mild and none required further endoscopic or surgical intervention. During a follow-up period of up to five years (median 25 months), only four patients (4.3%) showed symptomatic recurrence, but none required further treatment. CONCLUSION: POEM is a very effective and safe treatment for Taiwanese patients with achalasia, irrespective of their achalasia subtype or prior treatment failure.

A Structural Comparison of SARS-CoV-2 Main Protease and Animal Coronaviral Main Protease Reveals Species-Specific Ligand Binding and Dimerization Mechanism.

Animal coronaviruses (CoVs) have been identified to be the origin of Severe Acute Respiratory Syndrome (SARS)-CoV, Middle East respiratory syndrome (MERS)-CoV, and probably SARS-CoV-2 that cause severe to fatal diseases in humans. Variations of zoonotic coronaviruses pose potential threats to global human beings. To overcome this problem, we focused on the main protease (Mpro), which is an evolutionary conserved viral protein among different coronaviruses. The broad-spectrum anti-coronaviral drug, GC376, was repurposed to target canine coronavirus (CCoV), which causes gastrointestinal infections in dogs. We found that GC376 can efficiently block the protease activity of CCoV Mpro and can thermodynamically stabilize its folding. The structure of CCoV Mpro in complex with GC376 was subsequently determined at 2.75 Å. GC376 reacts with the catalytic residue C144 of CCoV Mpro and forms an (R)- or (S)-configuration of hemithioacetal. A structural comparison of CCoV Mpro and other animal CoV Mpros with SARS-CoV-2 Mpro revealed three important structural determinants in a substrate-binding pocket that dictate entry and release of substrates. As compared with the conserved A141 of the S1 site and P188 of the S4 site in animal coronaviral Mpros, SARS-CoV-2 Mpro contains N142 and Q189 at equivalent positions which are considered to be more catalytically compatible. Furthermore, the conserved loop with residues 46-49 in animal coronaviral Mpros has been replaced by a stable α-helix in SARS-CoV-2 Mpro. In addition, the species-specific dimerization interface also influences the catalytic efficiency of CoV Mpros. Conclusively, the structural information of this study provides mechanistic insights into the ligand binding and dimerization of CoV Mpros among different species.

Trilostane, a 3ß-hydroxysteroid dehydrogenase inhibitor, suppresses growth of hepatocellular carcinoma and enhances anti-cancer effects of sorafenib.

Background Human 3ß-hydroxysteroid dehydrogenase type 1 (HSD3B1) is an enzyme associated with steroidogenesis, however its' role in hepatocellular carcinoma (HCC) biology is unknown. Trilostane is an inhibitor of HSD3B1 and has been tested as a treatment for patients with breast cancer but has not been studied in patients with HCC. Methods and Results The expression of HSD3B1 in HCC tumors in 57 patients were examined. A total of 44 out of 57 tumors (77.2%) showed increased HSD3B1 expression. The increased HSD3B1 in tumors was significantly associated with advanced HCC. In vitro, the knockdown of HSD3B1 expression in Mahlavu HCC cells by a short hairpin RNA (shRNA) led to significant decreases in colony formation and cell migration. The suppression of clonogenicity in the HSD3B1-knockdown HCC cells was reversed by testosterone and 17ß-estradiol. Trilostane-mediated inhibition of HSD3B1 in different HCC cells also caused significant inhibition of clonogenicity and cell migration. In subcutaneous HCC Mahlavu xenografts, trilostane (30 or 60 mg/kg, intraperitoneal injection) significantly inhibited tumor growth in a dose-dependent manner. Furthermore, the combination of trilostane and sorafenib significantly enhanced the inhibition of clonogenicity and xenograft growth, surpassing the effects of each drug used alone, with no documented additional toxicity to animals. HSD3B1 blockade was found to suppress the phosphorylation of extracellular signal-regulated kinase (ERK). The decreased ERK phosphorylation was reversed by testosterone or 17b-estradiol. Conclusions Trilostane significantly inhibited the growth of HCC by inhibiting HSD3B1 function and augmenting the efficacy of sorafenib.

Endoscopic management of strictures in patients with Crohn's disease - A multi-center experience in Taiwan.

BACKGROUND/PURPOSE: Inflammatory bowel disease (IBD) is a chronic gastrointestinal (GI) disorder that causes relapsing inflammation and severe mucosal damage in the intestine. Crohn's disease (CD)-related stricturing complications are a major cause of surgery, disability, and reduced quality of life. Endoscopic balloon dilation (EBD) has been shown to reliably delay or prevent surgery in patients with stricturing CD. However, cases of EBD performed for stricture in CD in Taiwan are rare. In this study, we want to evaluate the experiences regarding EBD for stricturing CD in Taiwan. METHODS: We conducted a retrospective analysis of 9 medical centers in Taiwan. Patients with CD-related strictures who were treated with EBD were included and analyzed. RESULTS: In nine medical centers, a total of 26 CD patients (19 male, 7 female, mean disease duration 75.4 ± 65.2 months) underwent 42 EBD procedures during the study period. Among the subjects, an 83.3% (35/42) EBD success rate was seen, but 26.9% (7/26) patients underwent surgery after ineffective EBD. In the surgery group, the the small bowel strictures was high compared with the non-surgery group (p = 0.01). There were no significant differences in disease phenotype, disease duration or history of fistulizing disease. In the surgery group, immunosuppressant use was high, and 5-aminosalicylic acid (5-ASA) use was low compared with the non-surgery group. After EBD, the physicians tended to change the drugs, especially increasing the use of biologic agents. CONCLUSION: EBD is a safe and effective procedure for CD-related stricture, with a 83.3% success rate in Taiwan.

Taiwanese consensus recommendations for acute pancreatitis.

The incidence of acute pancreatitis and related health care utilization are increasing. Acute pancreatitis may result in organ failure and various local complications with risks of morbidity and even mortality. Recent advances in research have provided novel insights into the assessment and management for acute pancreatitis. This consensus is developed by Taiwan Pancreas Society to provide an updated, evidence-based framework for managing acute pancreatitis.

Fecal Microbiota Transplantation Prevents Intestinal Injury, Upregulation of Toll-Like Receptors, and 5-Fluorouracil/Oxaliplatin-Induced Toxicity in Colorectal Cancer.

FOLFOX (5-fluorouracil, leucovorin, and oxaliplatin), a 5-fluorouracil (5-FU)-based chemotherapy regimen, is one of most common therapeutic regimens for colorectal cancer. However, intestinal mucositis is a common adverse effect for which no effective preventive strategies exist. Moreover, the efficacy and the safety of fecal microbiota transplants (FMT) in cancer patients treated with anti-neoplastic agents are still scant. We investigated the effect of FMT on FOLFOX-induced mucosal injury. BALB/c mice implanted with syngeneic CT26 colorectal adenocarcinoma cells were orally administered FMT daily during and two days after five-day injection of FOLFOX regimen for seven days. Administration of FOLFOX significantly induced marked levels of diarrhea and intestinal injury. FMT reduced the severity of diarrhea and intestinal mucositis. Additionally, the number of goblet cells and zonula occludens-1 decreased, while apoptotic and NF-κB-positive cells increased following FOLFOX treatment. The expression of toll-like receptors (TLRs), MyD88, and serum IL-6 were upregulated following FOLFOX treatment. These responses were attenuated following FMT. The disrupted fecal gut microbiota composition was also restored by FMT after FOLFOX treatment. Importantly, FMT did not cause bacteremia and safely alleviated FOLFOX-induced intestinal mucositis in colorectal cancer-bearing mice. The putative mechanism may involve the gut microbiota TLR-MyD88-NF-κB signaling pathway in mice with implanted colorectal carcinoma cells.

Is papillary thyroid microcarcinoma a biologically different disease? A propensity score-matched analysis.

BACKGROUND: Papillary thyroid microcarcinoma exhibits an indolent clinical course and could be a candidate for active surveillance in the appropriate setting. It remains unknown whether papillary microcarcinoma is biologically different from larger papillary carcinoma >1 cm. METHODS: We analyzed clinicopathological information and transcriptome data of papillary thyroid cancer samples from The Cancer Genome Atlas. Propensity-score matching was used to construct a matched cohort consisting of 29 microcarcinomas and 58 carcinomas. Principal component analysis and unsupervised hierarchical cluster analysis were carried out to investigate the similarity of gene expression profiles. RESULTS: After adjustment for differences in baseline clinicopathological and genetic factors, transcriptome could be grouped mainly on the basis of tumor class (BRAF-like vs RAS-like) and tumor size (microcarcinoma vs carcinoma). The gene set enrichment analysis showed that extracellular matrix-associated pathways were enriched in the MSigDB database. CONCLUSION: Papillary thyroid microcarcinomas display a distinct gene expression pattern different from the corresponding carcinomas. We hypothesize that tumor microenvironment may play a role in the microcarcinoma/carcinoma phenotypic divergence.

Heme Oxygenase-1 Inhibitors Induce Cell Cycle Arrest and Suppress Tumor Growth in Thyroid Cancer Cells.

Heme oxygenase-1 (HO-1) is induced by a variety of stimuli and plays a multifaceted role in cellular protection. We have shown that HO-1 is overexpressed in thyroid cancer and is associated with tumor aggressiveness. Therefore, we set out to assess the effects of HO-1 inhibitors on the biology of thyroid cancer cells. Two different classes of HO-1 inhibitors were used, including a metalloporphyrin, zinc protoporphyrin-IX (ZnPP), and an azole antifungal agent, ketoconazole. The viability and colony formation of thyroid cancer cells decreased in a concentration- and time-dependent fashion following treatment with HO-1 inhibitors. Cancer cells exhibited a higher sensitivity to HO-1 inhibitors than non-malignant cells. HO-1 inhibitors induced a G0/G1 arrest accompanied by decreased cyclin D1 and CDK4 expressions and an increase in levels of p21 and p27. HO-1 inhibitors significantly increased intracellular ROS levels and suppressed cell migration and invasion. Oxygen consumption rate and mitochondrial mass were increased with ZnPP treatment. Mice treated with ZnPP had a reduced xenograft growth and diminished cyclin D1 and Ki-67 staining in tumor sections. Taken together, HO-1 inhibitors might have therapeutic potential for inducing cell cycle arrest and promoting growth suppression of thyroid cancer cells in vitro and in vivo.

Expression of 3ß-Hydroxysteroid Dehydrogenase Type 1 in Breast Cancer is Associated with Poor Prognosis Independent of Estrogen Receptor Status.

BACKGROUND: Human 3ß-hydroxysteroid dehydrogenase type 1 (HSD3B1) plays a vital role in steroidogenesis in breast tumors and may therefore be a suitable target for treatment of breast cancer. This study investigated the role of HSD3B1 in the pathogenesis of breast cancer in clinical and experimental settings. METHODS: Expression of HSD3B1 in primary tumors of 258 breast cancer patients was evaluated by immunohistochemistry. Screening of breast cancer cell lines indicated that triple-negative MDA-MB-231 cells expressed HSD3B1. The effects from genetic and pharmacologic inhibition of HSD3B1 were assessed in vitro and in vivo. RESULTS: The findings showed that 44% of the 258 breast cancers were HSD3B1-positive. The HSD3B1-positivity was associated with advanced-stage disease (p = 0.009) and reduced recurrence-free survival (p = 0.048) but not with tumor subtype or estrogen receptor status. Silencing of HSD3B1 or treatment with an HSD3B1 inhibitor (trilostane) reduced colony formation in breast cancer cells. Knockdown of HSD3B1 inhibited cell proliferation and migration. Analysis of a murine xenograft tumor model indicated that trilostane significantly slowed tumor growth. CONCLUSIONS: Expression of HSD3B1 in breast cancer is negatively associated with prognosis. The study found HSD3B1 to be a potential therapeutic target for breast cancer independent of estrogen receptor status.

Comparison of telbivudine and entecavir on the change of off- treatment eGFR after 3 years of treatment in non-cirrhotic chronic hepatitis B patients.

BACKGROUND: The change of estimated glomerular filtration rate (eGFR) with off-treatment nucleos(t)ide analogues (NA) in chronic hepatitis B patients (CHB) is unclear. This study is aimed to evaluate the off-treatment eGFR after 3 years of therapy with telbivudine (LdT) or entecavir (ETV) and to assess predictive factors for eGFR improvement. METHODS: From January 2009 to December 2011, we identified NA-naïve patients who were at least 20 years of age diagnosed with compensated CHB. All patients received a 3-year NA treatment and 1 year off-treatment follow-up; the initial selection of patients for LdT or ETV treatment was at the physicians' discretion. An increase of more than 10% in eGFR from the baseline was identified as an improvement. The change of chronic kidney disease stages were recorded and compared with baseline at year 3 and year 4, respectively. RESULTS: This study included two groups consisting of 46 patients each (each with3 years of treatment with LdT or ETV). In LdT-treated patients, the mean eGFR increased from 94.3 ± 28.3 to 104.0 ± 31.2 mL/min/1.73 m2 in year 3 (p = 0.01) and from 104.0 ± 31.2 to 104.0 ± 28.8 mL/min/1.73 m2 in year 4 (p = 0.99). However, in ETV-treated patients, the mean eGFR decreased from 93.1 ± 26.1 to 85.5 ± 25.1 mL/min/1.73 m2 in year 3 (p = 0.0009) and from 85.5 ± 25.1 to 87.7 ± 24.8 mL/min/1.73 m2 in year 4 (p = 0.2). After a multivariate analysis, the predictors for the off-treatment eGFR improvement were the LdT treatment (odds ratio [OR], 3.97 (1.37-11.5), p = 0.01) and pre-treated eGFR (OR, 0.98 (0.95-1.00), p = 0.04). CONCLUSIONS: At year 4, 48.8 and 21.3% patients had an improved eGFR from baseline in LdT and ETV patients, respectively. Telbivudine may have a protective renal effect that can last for one year after treatment in non-cirrhotic CHB patients without a virological breakthrough.

Effect of Perioperative Intravenous Lidocaine Infusion on Acute and Chronic Pain after Breast Surgery: A Meta-Analysis of Randomized Controlled Trials.

OBJECTIVES: Intravenous lidocaine infusion has been shown to reduce postoperative pain among patients undergoing abdominal surgery. This study aimed to evaluate the effects of perioperative lidocaine administration in breast surgery. METHODS: A meta-analysis of randomized controlled trials comparing lidocaine infusion vs. placebo/routine treatment was performed. Standardized mean difference (SMD) or risk ratio (RR) with 95% confidence intervals (CIs) was calculated from pooled data. Random-effects models were used, and heterogeneity was assessed. RESULTS: A total of 4 reports (3 primary studies and 1 extension) with 84 patients randomized to the lidocaine group and 83 patients randomized to the control group were included. There was no difference in pain scores at rest or during activity between the 2 groups from postoperative 2 hours to 3 days. At postoperative 72 hours, the lidocaine group had fewer analgesics consumed (SMD, -0.479; 95% CI, -0.914 to -0.043; P = 0.031). Chronic pain was assessed 3 to 6 months after breast surgery in 51 patients of the lidocaine group and 46 patients of the control group. Patients in the lidocaine group had significantly lower risk for the development of chronic pain (RR, 0.332; 95% CI, 0.141 to 0.781; P = 0.012). CONCLUSION: The results indicate no significant benefits of intravenous lidocaine infusion in terms of acute postoperative pain. Although lidocaine seems to attenuate the risk of chronic pain after breast surgery, there is insufficient evidence to conclude that lidocaine infusion is of proved benefit because the results were based on a limited number of small trials.

Aberrant expression of tumor-associated carbohydrate antigen Globo H in thyroid carcinoma.

BACKGROUND AND OBJECTIVES: The induction of tumor-associated carbohydrate antigen results from altered glycosylation in transformed cells. Globo H is a hexasaccharide glycosphingolipid overexpressed on malignancies of epithelial origin and has become an attractive vaccine target. We aimed to investigate the expression patterns and prognostic value of Globo H in thyroid neoplasms. METHODS: Globo H expression was examined by immunohistochemical analysis using commercial and in-house tissue microarrays. The expression was correlated with clinicopathologic characteristics in papillary thyroid cancer. RESULTS: Normal or benign thyroid lesions were negative for Globo H expression. Globo H was positive in 33% medullary, 24% papillary, 11% undifferentiated, and 8% follicular thyroid cancer. Globo H expression in papillary thyroid cancer was associated with extrathyroidal invasion (P = 0.017), BRAF mutation (P = 0.010), AMES high risk (P = 0.045), and increased ATA risk of recurrence (P = 0.022). CONCLUSIONS: Globo H is specifically expressed in a subset of thyroid malignancies. In papillary thyroid cancer, Globo H expression is associated with invasiveness and BRAF mutation. Immunotherapy targeting Globo H may have potential applications in thyroid cancer. J. Surg. Oncol. 2016;114:853-858. © 2016 2016 Wiley Periodicals, Inc.

A novel artificial tissue simulator for endoscopic submucosal resection training - a pilot study.

BACKGROUND: We developed a novel artificial simulator for endoscopic submucosal dissection (ESD) as a bridge between instructional videos and animal tissue training and aimed to evaluate the feasibility of using an artificial tissue model in ESD training. METHODS: Eight gastroenterology fellows from one medical center were enrolled in this ESD training program. Before and after the simulator training, attendees indicated on a 5-point scale the degree of difficulty in performing the following procedures: lesion marking, mucosal pre-cutting, circumferential incision, submucosal dissection, and hemostasis. After the simulator training, the participants completed a questionnaire regarding their opinions on the degree of realism and the feasibility of using this model for training. RESULTS: After watching an instructional video, attendees felt that the most difficult techniques were submucosal dissection and hemostasis. After using the artificial tissue simulator model, the attendees felt more confident in performing performing lesion marking (p = 0.026) and submucosal dissection (p = 0.037). However, they still felt that hemostasis was the most difficult techniques to master. Overall, the attendees thought the simulator was realistic in simulated lesion marking and its use was feasible for simulated lesion marking and submucosal dissection. CONCLUSION: Our pilot study shows the feasibility of using a novel artificial tissue in performing ESD and we believe that the artificial tissue simulator acts well as a bridge between instructional videos and animal model training. The model is reusable and inexpensive, and could disseminate the techniques of the ESD more easily and quickly.

Ribose-5-phosphate isomerase A regulates hepatocarcinogenesis via PP2A and ERK signaling.

The deregulated nonoxidative pentose phosphate pathway (PPP) is known to promote oncogenesis, but the molecular mechanism remains unknown. Here, we report that human ribose-5-phosphate isomerase A (RPIA) plays a role in human hepatocellular carcinoma (HCC). A significant increase in RPIA expression was detected both in tumor biopsies of HCC patients and in a liver cancer tissue array. Importantly, the clinicopathological analysis indicated that RPIA mRNA levels were highly correlated with clinical stage, grade, tumor size, types, invasion and alpha-fetoprotein levels in the HCC patients. In addition, we demonstrated that the ability of RPIA to regulate cell proliferation and colony formation in different liver cancer cell lines required ERK signaling as well as the negative modulation of PP2A activity and that the effects of RPIA could be modulated by the addition of either a PP2A inhibitor or activator. Furthermore, the xenograft studies in nude mice revealed that the modulation of RPIA in liver cancer cells regulated tumor growth and that NIH3T3 cells overexpressing RPIA exhibited increased proliferation, enhanced colony formation, elevated levels of p-ERK1/2 and accelerated tumor growth. This study provides new insight into the molecular mechanisms by which RPIA overexpression can induce oncogenesis in HCC. Furthermore, it suggests that RPIA can be a good prognosis biomarker and a potential target for HCC therapy.