A new platform for laparoscopic training: initial evaluation of the ex-vivo live multivisceral training device.

BACKGROUND: Various training models have been developed for laparoscopic training. Inanimate models including cadavers, ex-vivo simulator, and virtual reality (VR), are less realistic and often fail to display specific events such as bleeding, bile leakage, etc. Animal models provide more realistic experience, but constraints like cost involved, anesthetic requirement, and ethical approval have limited its application. We have designed a new training ex-vivo simulator-Smagister to address these issues. METHODS: The Smagister consists of a normothermic machine perfusion platform, multivisceral organ of porcine abdominal cavity (liver, gallbladder, pancreas, stomach, intestine, kidney, uterus, bladders, etc.), high-definition display, and software system. Blood gas analysis and number of peristalsis per hour were recorded. A questionnaire was used to subjectively assess vitality of the organ cluster every hour. Three laparoscopic procedures including cholecystectomy (LC), enterotomy closure (LEC) and hepatectomy (LLR) were performed on Smagister, with demonstration of specific events for each procedure. Six experts compared the procedures with actual surgery in terms of feasibility to complete procedures and demonstration of complications. RESULTS: The fluctuation of perfusate glucose (6.1-8.2 mmol/L) and lactate (5.82-6.55 mmol/L) suggested metabolic function of the multivisceral organs. The mean number of peristalsis was 2.2/min. The simulated surgical view and anatomic structures closely resembled actual surgery during continuous perfusion (3.5 ± 1.0, 3.8 ± 0.8, respectively). The evaluation scores of haptic feedbacks were 3.8 ± 0.8, resembling live tissue handling. LC, LEC, and LLR were performed well on the Smagister, with clear display of the specific events. All six experts considered Smagister as a suitable training modality for both basic and advanced laparoscopic surgery. CONCLUSION: The amalgamation of live animal model and ex-vivo simulation in Smagister centralizes the virtue of both modalities, expands the training field, and provides high-fidelity laparoscopic training for both novice and senior surgeons.

The PROFILE of assessment program for internal medicine internship of Sun Yat-Sen University.

Objective: To reflectively look at the present methods by which the clinical competence of 5th-year medical students (i.e. interns) in Sun Yat-Sen University (SYSU) are assessed upon finishing internship rotation in internal medicine (IM). Methods: Current procedures for the competence assessment of end-of-rotation IM interns in the First Affiliated Hospital of SYSU were reviewed, along with a point-by-point appraisal based on the PROFILE approach to structured assessment, and, whenever possible, suggestions for future improvement. Results and discussions: On a scale of 1-10, with 10 being the best or the most ideal, our marks for current methods to assess end-of-rotation IM interns in terms of being Programmatic, Real-World, Outcome-based, Formative, Impactful, Learner-engaged, and Evaluation-guaranteed were 7, 9, 3, 4, 6, 8, and 1, respectively. The strengths, weaknesses as well as potential solutions in each of the seven aspects are also discussed separately. Conclusions: Current assessment program for IM internship is strong in being programmatic, real-world, educationally impactful and learner engaged, and has room for further improvement in its time-based arrangements, relative shortage of feedback provision, as well as a systematic lack of quality control measures.

LncRNA FLVCR1-AS1 acts as miR-513c sponge to modulate cancer cell proliferation, migration, and invasion in hepatocellular carcinoma.

In the present study, we aimed to search for dysregulated lnRNAs in Hepatocellular carcinoma (HCC) tissues, and analyze the relationship of its expression level with the clinicopathological feature and patient prognosis. The biological function of FLVCR1-AS1, the identified lncRNA, in the process of HCC development, and progression was investigated in vitro and in vivo. The underlying molecular mechanism was further explored. We determined FLVCR1-AS1 expression in HCC tissues and peri-tumor tissues by bioinformatic analysis, qRT-PCR, Northern blot and in situ hybridization. The relationship between FLVCR1-AS1 expression level and prognosis was determined by analyzing clinical samples. The effects of FLVCR1-AS1 knockdown on HCC cell proliferation, apoptosis, migration, and invasion were investigated by CCK8, FACS, and tanswell assay, respectively. Tumor xenograft model was used to determine the influence of down-regulated FLVCR1-AS1 on tumor growth and metastasis. lncRNA FLVCR1-AS1 was extremely up-regulated in HCC tissues and cell lines. FLVCR1-AS1 expression level was positively correlated with tumor severity. FLVCR1-AS1 knockdown remarkably inhibited HCC cell proliferation, migration, and invasion in vitro and in vivo while induced cell apoptosis. In mechanism, FLVCR1-AS1 acted as a competitive endogenous RNAs to sponge miR-513c which targeted the mRNA of MET for degradation. By directly sponging miR-513c, FLVCR1-AS1 increased MET expression in HCC, and then promoted HCC progression. It was demonstrated that FLVCR1-AS1 played a positive role in HCC development and progression according to the study in its mechanism, function and clinical manifestation, so that it could be expected to become a new target in HCC prevention and treatment.

Serum CYFRA 21-1 in Biliary Tract Cancers: A Reliable Biomarker for Gallbladder Carcinoma and Intrahepatic Cholangiocarcinoma.

BACKGROUND: Biliary tract cancers encompass gallbladder carcinoma, and intrahepatic, perihilar and distal cholangiocarcinoma. Upregulated serum CYFRA 21-1 has been reported in intrahepatic cholangiocarcinoma. AIMS: The present study aimed to explore the clinical significance of serum CYFRA 21-1 in all biliary tract cancer subtypes. METHODS: Serum CYFRA 21-1, carbohydrate antigen 19-9 and carcinoembryonic antigen were quantitated preoperatively, postoperatively and during follow-up in 134 malignant and 52 benign patients. Receiver operator characteristic curves of biomarkers were analyzed. Level of CYFRA 21-1 was correlated with patients' clinicopathological features and follow-up data. RESULTS: CYFRA 21-1 was significantly upregulated in biliary malignancies, and expressional difference existed between these subtypes. Based on the maximal Youden's index, cutoff values were selected (ng/mL): 2.61 for biliary tract cancers (sensitivity 74.6 % and specificity 84.6 %); 3.27 for intrahepatic cholangiocarcinoma (75.6 and 96.2 %) and gallbladder carcinoma (93.7 and 96.2 %); 2.27 for perihilar cholangiocarcinoma (71.0 and 71.2 %); and 2.61 for distal cholangiocarcinoma (63.3 and 84.6 %). CYFRA 21-1 showed better diagnostic performance than other biomarkers in gallbladder carcinoma and intrahepatic cholangiocarcinoma; its performance was not inferior to that of the combination of these three biomarkers and declined after curative resection and re-elevated when tumor recurred, which was correlated with tumor aggressiveness and TNM stage; it was an independent predictor for 1-year recurrence-free survival and overall survival on multivariate analysis. CONCLUSION: Serum CYFRA 21-1 represents a reliable biomarker for gallbladder carcinoma and intrahepatic cholangiocarcinoma.

DNA methylation profiling identifies EYA4 gene as a prognostic molecular marker in hepatocellular carcinoma.

BACKGROUND: DNA hypermethylation plays important roles in carcinogenesis by silencing key genes. This study aims to identify pivotal genes in hepatocellular carcinoma (HCC) by DNA methylation microarray and to assess their prognostic values. MATERIALS AND METHODS: DNA methylation microarray was performed in 45 pairs of HCC and adjacent nontumorous tissues and six normal liver tissues to identify hypermethylated genes in HCC. Potential prognosis-related genes were selected among hypermethylated genes by analyzing influences of methylation levels on disease-free survival (DFS) and overall survival (OS) in 45 patients. Their prognostic values were validated in 154 patients with HCC (including the initial 45 patients) to determine the independent prognostic gene. RESULTS: Altogether, 54 CpG islands in 44 genes were hypermethylated in HCC compared with liver tissues. Among them, methylation levels of ERG and HOXA11 were inversely associated with DFS (both P < 0.050), and methylation levels of EYA4 were inversely related to DFS and OS (both P < 0.050). EYA4 expression was inversely related to tumor size (P < 0.050). Lower EYA4 expression and larger tumor size were independent predictors of both shorter DFS and OS, and higher Barcelona Clinic Liver Cancer (BCLC) staging was an independent predictor of shorter OS (all P < 0.050). CONCLUSIONS: EYA4 functions as a prognostic molecular marker in HCC. Its aberrant hypermethylation and subsequent down-regulation may promote tumor progression.

Reflecting on Experiences of Senior Medical Students' External Clinical Teaching Visits in General Practice Placements: A Pilot Study.

Purpose: Australian general practice training uses external clinical teaching (ECT) visits for formative work-based assessments. ECT visits appoint senior general-practitioners (GPs) observe trainee GPs' consultations, provide feedback, and make performance-enhancing recommendations. As ECT visits are one of the best assessment tools in Australian GP training, there is limited evidence of its use in undergraduate teaching. This study aims to introduce ECT visits and evaluate assessment tools during senior medical students' GP placement. Methods: This study included external and internal GP supervisors and twenty-five Chinese and Australian students during GP placements. The supervisors provided structured in-person feedback, while the ECT assessment tool used a standardised, validated feedback platform to assess every component of a consultation. Students' feedback was recorded and collected by both internal and external supervisors, and then semantically analysed by external supervisors. Results: Twenty-five ECT visit feedbacks were collected and analysed semantically. All participating students rated ECT visits excellently and confirmed the relevance of assessment tools for discussions with supervisors to achieve the designed learning outcomes. Chinese students rated the assessment tools as innovative from a cultural perspective and recommended the ECT visit teaching model and assessment tools to their home university, whereas Australian students suggested more ECT visits during GP placements. Time management was a limitation for both the students and supervisors. Conclusion: ECT visit is an innovative placement teaching model and work-based assessment tool for senior medical students' GP placements, and is rated as the most preferred formative assessment tool. The limitations of this study include small group of students/supervisors and lack of patient feedback; however, all of these limitations can be overcome by involving multiple GP clinics in ongoing large-scale study. ECT visits can be introduced quantitatively into students' GP placement curricula to improve clinical reasoning, learning, and quality assurance with assessments during clinical placements.

Micro-Engineered Organoid-on-a-Chip Based on Mesenchymal Stromal Cells to Predict Immunotherapy Responses of HCC Patients.

Hepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide. Patient-derived organoid (PDO) has great potential in precision oncology, but low success rate, time-consuming culture, and lack of tumor microenvironment (TME) limit its application. Mesenchymal stromal cells (MSC) accumulate in primary site to support tumor growth and recruit immune cells to form TME. Here, MSC and peripheral blood mononuclear cells (PBMC) coculture is used to construct HCC organoid-on-a-chip mimicking original TME and provide a high-throughput drug-screening platform to predict outcomes of anti-HCC immunotherapies. HCC-PDOs and PBMC are co-cultured with MSC and Cancer-associated fibroblasts (CAF). MSC increases success rate of biopsy-derived PDO culture, accelerates PDO growth, and promotes monocyte survival and differentiation into tumor-associated macrophages. A multi-layer microfluidic chip is designed to achieve high-throughput co-culture for drug screening. Compared to conventional PDOs, MSC-PDO-PBMC and CAF-PDO-PBMC models show comparable responses to chemotherapeutic or targeted anti-tumor drugs but more precise prediction potential in assessing patients' responses to anti-PD-L1 drugs. Moreover, this microfluidic platform shortens PDO growth time and improves dimensional uniformity of organoids. In conclusion, the study successfully constructs microengineered organoid-on-a-chip to mimic TME for high-throughput drug screening, providing novel platform to predict immunotherapy response of HCC patients.

Monoamine oxidase A expression is suppressed in human cholangiocarcinoma via coordinated epigenetic and IL-6-driven events.

The secretion of dopamine and serotonin is increased in cholangiocarcinoma, which has growth-promoting effects. Monoamine oxidase A (MAOA), the degradation enzyme of serotonin and dopamine, is suppressed in cholangiocarcinoma via an unknown mechanism. The aims of this study were to (i) correlate MAOA immunoreactivity with pathophysiological parameters of cholangiocarcinoma, (ii) determine the mechanism by which MAOA expression is suppressed and (iii) evaluate the consequences of restored MAOA expression in cholangiocarcinoma. MAOA expression was assessed in cholangiocarcinoma and nonmalignant controls. The control of MAOA expression by promoter hypermethylation was evaluated and the contribution of interleukin-6 (IL-6) signaling to the suppression of MAOA expression was determined. The effects of MAOA overexpression on cholangiocarcinoma growth and invasion were also assessed. MAOA expression is correlated with differentiation, invasion and survival in cholangiocarcinoma. The MAOA promoter was hypermethylated immediately upstream of the start codon in cholangiocarcinoma samples and cell lines but not in nonmalignant counterparts. IL-6 signaling also decreased MAOA expression via a mechanism independent of hypermethylation, involving the regulation of the balance between SP-1 transcriptional activity and its inhibitor, R1 repressor. Inhibition of both IL-6 signaling and DNA methylation restored MAOA levels to those observed in cholangiocytes. Forced MAOA overexpression inhibited cholangiocarcinoma growth and invasion. MAOA expression is suppressed by the coordinated control of promoter hypermethylation and IL-6 signaling. MAOA may be a useful prognostic marker in the management of cholangiocarcinoma, and therapies designed to increase MAOA expression might prove beneficial in the treatment of cholangiocarcinoma.

Indocyanine Green-Guided Intraoperative Imaging to Facilitate Video-Assisted Retroperitoneal Debridement for Treating Acute Necrotizing Pancreatitis.

Video-assisted retroperitoneal debridement (VARD) is a feasible, minimally invasive necrosectomy method for treating severe acute necrotizing pancreatitis, if it does not resolve or is accompanied with infected necrosis in the retroperitoneum. As there are rarely any visually clear separating surface in white light image between necrotic debris and adjacent inflammatory normal tissues due to extensive retroperitoneal adhesions, VARD is accompanied with the risk of vascular injury, external pancreatico-cutaneous or enterocutaneous fistulae. In view of the above disadvantages, we apply real-time intraoperative near-infrared fluorescence imaging with indocyanine green (ICG) during VARD, which enables visualization of the well-perfused adjacent normal tissues. This modified technique (ICG-guided VARD) can provide a clear separating surface during debridement and reduce the risk of vascular or enteric injury. ICG-guided VARD may facilitate surgeons to perform safer debridement in treating severe acute necrotizing pancreatitis.

LncRNA MYCNOS facilitates proliferation and invasion in hepatocellular carcinoma by regulating miR-340.

Hepatocellular carcinoma (HCC) remains one of the most common and aggressive human cancers worldwide. Accumulating evidences indicate that non-coding RNAs are critical regulators implicated in various physiological processes including HCC development. Long non-coding RNA (lncRNA) MYCN opposite-strand (MYCNOS) was reported to be up-regulated in several human cancers, yet its role in HCC progression is still elusive. In the present study, MYCNOS was up-regulated in both HCC tissues and cell lines, and elevated MYCNOS expression was correlated to shorter survival time of HCC patients. We knocked down MYCNOS expression using short hairpin RNAs specifically targeting MYCNOS. MYCNOS knockdown significantly inhibited proliferation in HCC cells in vitro accompanied by exacerbated cell apoptosis; it also suppressed tumor growth in mouse model in vivo. Besides, the migration and invasion of HCC cells were remarkably inhibited after MYCNOS knockdown. In addition, MYCNOS acted as a negative regulator of miR-340 in HCC cells, and all effects of MYCNOS knockdown were abrogated by further miR-340 inhibition. We also discovered that oncogene phosphatidylinositol-3, 4, 5-trisphosphate-dependent Rac exchange factor 2 (PREX2) was a downstream target of miR-340, and PREX2 expression was positively correlated to that of MYCNOS in HCC tissues. In conclusion, our findings demonstrated that MYCNOS knockdown inhibited HCC progression through regulating miR-340.

Multifunctional MoS2 nanosheets with Au NPs grown in situ for synergistic chemo-photothermal therapy.

The treatment of cancer has always been a worldwide problem. The combination of chemotherapy and other therapies would be a promising therapy strategy. Photothermal therapy (PTT) does not cause serious side effects and has dual control of time and space, which was considered to be a good method for combination with chemotherapy. Here, we modified multifunctional nanosheets based on in-situ gold nanoparticles (Au NPs) grown molybdenum disulfide (MoS2) to combine their excellent photothermal conversion and drug loading capabilities. More importantly, the target peptide cRGD modified nanosheets have good selectivity to tumor cells rich in integrin receptors, and drug loading and drug release tests showed that it could carry enough chemotherapeutic drugs and had excellent photo controlled release performance. In vitro cell experiments showed that the drug-loaded multifunctional nanosheets had good anti-tumor effect under 808 nm laser irradiation. Therefore, the multifunctional nanosheets designed in this paper have great potential in the study of targeted drug release and chemo-photothermal therapy combined therapy, and are of great significance for in vivo and clinical research.

Activation of c-Jun predicts a poor response to sorafenib in hepatocellular carcinoma: Preliminary Clinical Evidence.

We determined the mitogen-activated protein kinase (MAPK) gene expression profile of acquired resistance in sorafenib-sensitive hepatocellular carcinoma (HCC) cells and aimed to identify c-Jun as an important molecule mediating the efficacy of sorafenib. Differences in gene expression of the MAPK signaling between untreated and sorafenib-treated HCC cell lines were investigated using real-time polymerase chain reaction array. Western blot and real-time PCR further evaluated the expression of c-Jun. Pathological specimens from 50 patients with advanced HCC were collected to measure p-c-Jun expression. Sorafenib-resistant HCC cells demonstrated greater levels of basal c-Jun mRNA and protein compared with sorafenib-sensitive HCC cells. Sorafenib activated p-c-Jun in a dose- and time-dependent manner in PLC/PRF/5 and MHCC97H cell lines. Decreased expression levels of 6 genes after sorafenib treatment suggested a robust inhibitory impact of sorafenib on MAPK signaling in HCC cells. c-Jun and p-c-Jun expression levels were inversely correlated with the efficacy of sorafenib; a high expression level of p-c-Jun was associated with resistance to sorafenib and poor overall survival in patients with clinical HCC. p-c-Jun may act as a biomarker for predicting responses of sorafenib treatment, thus advocating targeting of JNK/c-Jun signaling as an optimal therapeutic strategy in a subset of HCC.

EYA4 functions as tumor suppressor gene and prognostic marker in pancreatic ductal adenocarcinoma through ß-catenin/ID2 pathway.

Eye absent homolog 4 (EYA4) was initially found as key gene in controlling eye development in Drosophila. We recently found that EYA4 was an independent prognostic factor in hepatocellular carcinoma. Its biological functions in malignancies remained unknown. The present study aimed at investigating its biological functions, molecular mechanisms and prognostic values in pancreatic ductal adenocarcinoma (PDAC). Overexpression of EYA4 in PDAC cells inhibited proliferation and invasion in vitro and tumor growth in vivo. Depletion of EYA4 in PDAC cells enhanced proliferation and invasion in vitro and tumor growth in vivo. Mechanistically, armed with the serine/threonine-specific protein phosphatase activity, EYA4 dephosphorylated ß-catenin at Ser675, blocked ß-catenin nuclear translocation and inhibited ID2 transactivation. Consistently, EYA4 expression inversely correlated with the levels of p-Ser675-ß-catenin and ID2 in tissues. EYA4 expression in PDAC tissues was significantly reduced as compared with adjacent non-tumoral tissues. EYA4 expression was an independent prognostic factor in PDAC, with a lower EYA4 level in association with shorter long-term survival and disease-free time. We showed that EYA4 functioned as tumor suppressor gene in PDAC via repressing ß-catenin/ID2 activation, and was an independent prognostic factor in PDAC.

Application of ultrasonic to speciation analysis of heavy metals in soil.

In order to reduce the operation time and improve the extraction efficiency, ultrasonic energy by means of ultrasonic bath was used to the modified Tessier sequential extraction for speciation analysis of heavy metals in soil. Extractable contents of Cu, Fe, Mn, Ni, Pb and Zn were measured by atomic absorption spectroscopy (AAS). The merit of the ultrasonic extraction (UE) applied to the modified Tessier method is not only that the operation time for the first 4 fractions was reduced from ca. 18 h to 8 h, comparing with conventional extraction (CE), but also the extraction efficiency was higher. The results for both of UE and CE were consistent. The extractable Cu, Ni and Zn in the sample No. 1 were mainly associated with the third fraction (Fe-Mn oxides fraction), and fourth fraction (organic matter fraction) in the sample No.2. The extractable Fe and Mn were all mainly associated with the third fraction, and Pb the fourth fraction in both of the samples. The effects of concentration of hydroxylamine chloride on the capability for the extraction of studied metals were also studied.

Inhibition of Wnt signaling induces cell apoptosis and suppresses cell proliferation in cholangiocarcinoma cells.

The aim of the present study was to explore possible gene therapy for hilar cholangiocarcinoma by detecting the activation of the Wnt signaling pathway in 4 cholangiocarcinoma cell lines and inhibiting its expression by RNA interference (RNAi) targeting key factors of this pathway. The expression levels of the Wnt pathway-related factors, Wnt2, Wnt3, ß-catenin and transcription factor 4, and its target genes, c-myc and cyclin D1, in 4 cholangiocarcinoma cell lines were detected by RT-PCR, western blotting and immunofluorescence microscopy. After transfection of siRNAs targeting Wnt2 and ß-catenin into FRH0201 cells, the expression of the Wnt pathway-related factors and its target genes was again detected, and the cell cycle distribution, apoptosis and proliferation were analyzed by flow cytometry and MTT assay. Activation of the Wnt pathway and the expression of its target genes were detected in all 4 cell lines at various levels. After siRNA transfection, the expression of the target genes in the FRH0201 cells was significantly downregulated. In addition, the Wnt pathway was blocked, cell apoptosis was enhanced and cell proliferation was suppressed. In conclusion, the Wnt signaling pathway is activated in cholangiocarcinoma cells. RNAi technology targeting Wnt2 and ß-catenin may be a possible gene therapy for hilar cholangiocarcinoma.

Killing effects of different physical factors on extracorporeal HepG2 human hepatoma cells.

OBJECTIVE: To determine the killing effects on extracorporeal HepG2 cells under different temperatures, pressures of permeability and lengths of treatment time. METHOD: According to different temperatures, pressures of permeability and lengths of treating time, extracorporeal HepG2 cells of human hepatoma cell-line were grouped to 80 groups. Cell index (CI) as the measurement of killing effect were calculated by monotetrazolium (MTT) methods, i.e., CI = 1 - (the OD value in treated group - the OD value in blank control group)/(mean of untreated control group - mean of blank control group). According to the factorial design, data were fed into SPSS 10.0 and analyzed by three-way ANOVA (analysis of variance). RESULT: Temperature, pressure of permeability and length of treating time all had effects on the CI (cell index) level. Length of treating time was the most influential factor of the three. Additionally, any two of them all had statistically significant interactive effects on the CI level. When treated for 5-30 min, destilled water at 46 degrees C stably generated the highest CI. CONCLUSION: The "46 degrees C-destilled water-60 min" was considered as the optimal combination of conditions which lead to highest CI. We suggest exerting celiac lavage for 15 min with stilled water at 40 degrees C-43 degrees C in surgical practice as a hyperthermia treatment to achieve ideal killing effects on free cancer cells, which is feasible, practical, and clinically effective.