Laparoscopic training on virtual-reality simulators or live pigs-a randomized controlled trial.

This randomized controlled trial compared the efficacy of virtual-reality (VR) simulator training and surgical training on live pigs to explore the most effective and evidence-based training modality. Materials and methods: Thirty-six novice surgical residents without independent laparoscopic experience were randomly paired with a peer and randomized into three groups: VR simulator group (dyad training on LapSim VR simulators), pig surgery group (training on live, anesthetized pigs) and control group (training by a lecture on laparoscopic surgery, surgical videos and textbooks). After 6 h of training, all participants performed a simulated cholecystectomy procedure using a pig liver with adherent gallbladder working in pairs. All procedures were video-recorded and the recordings were saved on USB-sticks in a blinded fashion identifiable only by the unique participant number. All video-recordings were scored blindly and independently by two expert raters using the Global Operative Assessment of Laparoscopic Skills (GOALS) assessment instrument. Results: The performances in the three groups were significantly different, P less than 0.001. Both the VR simulation training group and the live pigs training group performed significantly better than the control group, both P values less than 0.001. However, there was no significant difference in the performance of the two simulation-based training groups, P=0.66. Conclusion: Novice surgical trainees can benefit from both VR simulator training and pig surgery simulation compared with traditional studying and there was no significant difference between the two modalities. The authors recommend that VR simulators should be used for basic training of laparoscopic skills and surgery on live animals should be reserved for higher-level surgical training.

An extracorporeal bioartificial liver embedded with 3D-layered human liver progenitor-like cells relieves acute liver failure in pigs.

Clinical advancement of the bioartificial liver is hampered by the lack of expandable human hepatocytes and appropriate bioreactors and carriers to encourage hepatic cells to function during extracorporeal circulation. We have recently developed an efficient approach for derivation of expandable liver progenitor-like cells from human primary hepatocytes (HepLPCs). Here, we generated immortalized and functionally enhanced HepLPCs by introducing FOXA3, a hepatocyte nuclear factor that enables potentially complete hepatic function. When cultured on macroporous carriers in an air-liquid interactive bioartificial liver (Ali-BAL) support device, the integrated cells were alternately exposed to aeration and nutrition and grew to form high-density three-dimensional constructs. This led to highly efficient mass transfer and supported liver functions such as albumin biosynthesis and ammonia detoxification via ureagenesis. In a porcine model of drug overdose-induced acute liver failure (ALF), extracorporeal Ali-BAL treatment for 3 hours prevented hepatic encephalopathy and led to markedly improved survival (83%, n = 6) compared to ALF control (17%, n = 6, P = 0.02) and device-only (no-cell) therapy (0%, n = 6, P = 0.003). The blood ammonia concentrations, as well as the biochemical and coagulation indices, were reduced in Ali-BAL-treated pigs. Ali-BAL treatment attenuated liver damage, ameliorated inflammation, and enhanced liver regeneration in the ALF porcine model and could be considered as a potential therapeutic avenue for patients with ALF.

Overexpressed ACP5 has prognostic value in colorectal cancer and promotes cell proliferation and tumorigenesis via FAK/PI3K/AKT signaling pathway.

The tartrate-resistant acid phosphatase (TRAP/ACP5) correlated with tumor progression in many malignancies. However, the role of ACP5 in colorectal cancer (CRC) has not been thoroughly elucidated. In this study, we sought to identify the role for ACP5 in CRC progression. Immunohistochemistry revealed that high ACP5 expression is positively associated with tumor size, tumor classification, lymph node metastasis, distant metastasis and advanced stage cancer in 285 CRC patients. Moreover, high ACP5 expression was significantly associated with poor overall survival and disease-free survival. Then, ectopic expression of ACP5 promoted tumor cell proliferation and invasion, whereas suppression of ACP5 expression resulted in decreased cell proliferation and invasion in colorectal cell lines in vitro. And, inhibition of ACP5 also inhibited growth of engrafted tumors in vivo. Furthermore, we found that ACP5 overexpression positively regulated p-FAK, p-PI3K and p-AKT in CRC cells. ACP5 depletion showed the opposite effects. What's more, overexpression of FAK in CRC cells could restore the reduced abilities of cell proliferation and invasion caused by siRNAs-ACP5. Finally, we found the inhibition of activity by Akt inhibitors, MK2206, could partially decrease the positive effects of ACP5 on CRC cell proliferation and invasion. In conclusion, our results suggest that overexpressed ACP5 might serve as an indicator for poor prognosis in colorectal cancer patients through regulation of FAK/PI3K/AKT signaling pathway, which might be a potential therapeutic approach for colorectal cancer therapy.

Jagged-1 attenuates LPS-induced apoptosis and ROS in rat intestinal epithelial cells.

Ulcerative colitis (UC) is a chronic, non-specific inflammatory disease that occurs in the colonic mucosa. This study investigated the role of the Notch pathway in affecting the pathogenesis of UC and regulating intestinal epithelial cell proliferation and apoptosis. Caspase-3 activity was measured and flow cytometry was used to detect reactive oxygen species (ROS) content and Ki-67 expression. Flow cytometry was applied to detect apoptosis, proliferation, and ROS content. Under LPS stimulation conditions, the IEC-6 cells were divided into 3 groups, including control, 5 and 10 µg/mL Jagged-1 protein pretreatment. The mRNA and protein expressions of Jagged-1, Notch1, Hes1, and OLFM4 in colon tissues were detected by real-time quantitative PCR (qRT-PCR) and Western blot. The ROS production, Ki-67 expression, and caspase-3 activity were significantly increased, and Jagged-1, Notch1, Hes1, and OLFM4 mRNA and protein levels were obviously elevated in the colon tissue of UC model rats compared with control. LPS treatment apparently up-regulated Jagged-1, Notch1, and OLFM4 expression in IEC-6 cells, resulting in marked enhancement in apoptosis and ROS generation, and reduction of proliferation. Administration of Jagged-1 before LPS stimulation further upregulated the expressions of Notch1 and OLFM4 in IEC cells, weakened apoptosis and ROS production, and alleviated the inhibitory effect of LPS on IEC-6 cell proliferation. UC lesions can activate the Notch signaling pathway in colon tissue, which may play a role in emergency repair. Upregulation of the Notch signaling pathway significantly reduced inflammatory stimuli-induced apoptosis and ROS generation in intestinal epithelial cells, resulting in increased cell proliferation.

Elevated expression of ECT2 predicts unfavorable prognosis in patients with colorectal cancer.

Epithelial cell transforming sequence 2 (ECT2) is a well-studied guanine nucleotide exchange factor for the Rho family GTPase, which has been demonstrated as an oncogene in many types of human cancers. However, little is known about the prognostic value of ECT2 in colorectal cancer (CRC). In current study, we investigated the expression pattern and underlying clinical significance of ECT2 in CRC. ECT2 expression was detected in 345 CRC specimens by immunohistochemistry, and its correlation with clinicopathologic parameters and prognosis of CRC patients were analyzed. Data from Oncomine database and real-time PCR demonstrated that ECT2 expression was elevated in CRC compared with normal tissues. Among the clinical parameters analyzed, high expression level of ECT2 significantly associated with tumor size (P=0.020), serum CEA levels (P = 0.000) and TNM stage (P=0.027). Kaplan-Meier survival analysis showed that patients with high ECT2 expression had a remarkably shorter overall survival. Cox regression analysis revealed that ECT2 expression level was a significant and independent prognostic factor for overall survival rate of CRC patients. These data suggested that ECT2 is an unfavorable biomarker of prognosis in CRC and that ECT2 may be a potential therapeutic candidate for CRC treatment.

[Impact of lysosome-associated protein transmembrane-4 beta on proliferation and invasion of colorectal cancer].

OBJECTIVE: To determine whether lysosome-associated protein transmembrane-4 beta (LAPTM4B) over-expression is associated with the proliferation and invasion in colorectal cancer (CRC). METHODS: Thirty pairs of CRC tissues, containing carcinoma and adjacent tissues, were used for the examination of LAPTM4B mRNA expression by real-time quantitative PCR (qPCR) assays. Then immunohistochemistry was performed to examine LAPTM4B protein expression in 6 pairs of CRC tissues. Over-expression LAPTM4B and low-expression LAPTM4B cell models were constructed with HCT116 CRC cell lines. CCK8 assay was used to detect the proliferation and Transwell assay was used to detect the invasion of the model cells. RESULTS: qPCR and immunohistochemistry results showed that LAPTM4B expression levels in CRC were higher compared to adjacent tissues (all P<0.01). CCK8 and Transwell assays results showed that LAPTM4B promoted proliferation and invasion of HCT116 cell lines model cells (all P<0.01). CONCLUSION: LAPTM4B promotes the proliferation and invasion in CRC patients, and may be used as an important potential marker.

Surgical intervention after catheter removal in a case of refractory peritoneal dialysis-related peritonitis.

Peritonitis is the most common infection in peritoneal dialysis (PD) and has been noted to be not only a cause of mortality but also the leading cause of technique failure in patients maintained on PD. Appropriate management of peritonitis to improve patient outcome has been the focus of clinical practice. We report a case of refractory PD-related peritonitis with surgical intervention intending to control ongoing peritoneal infection despite aggressive antibiotics and timely catheter removal. Exploratory laparotomy was performed in this case, and an encapsulated abscess in the peritoneal and pelvic cavity was obliterated. Adhesiolysis was done simultaneously. Continuous postoperative peritoneal lavage and drainage were implemented. Symptoms dramatically improved after operation, and indwelling tubes were removed several days later. Finally, the patient recovered and switched to permanent hemodialysis without intra-abdominal complications. Our case suggested that appropriate and timely surgical intervention in refractory peritonitis is necessary for saving lives in certain subgroups of patients. Clearly, well-designed studies with large samples are warranted to explore this issue in more detail.

Evidence of positive selection at signal peptide region of interferon gamma.

Interferon gamma (IFNG) is a major cytokine and plays crucial roles in pathogen clearance. About the course of evolution of IFNG, it has been reported that IFNG is being subjected to adaptive selection, which is proved at the level of gene. Neighbor-joining method was used to reconstruct the phylogenetic tree of all IFNG protein-coding sequences. The pair-wise computation of Ka/Ks between every exon homologs, branch-specific model, and site-specific model of the likelihood method were performed to detect positive selection of IFNG. We reported, for the first time, that the signal peptide region of IFNG is under significant positive selection, evolving faster than other parts. We provide evidence at the level of individual exon and individual amino acid site that IFNG is under adaptive evolution, which establishes the basis for further researches about IFNG.

Incidence and mortality of anastomotic dehiscence requiring reoperation after rectal carcinoma resection.

Anastomotic dehiscence (AD) requiring reoperation is the most severe complication following anterior rectal resection. We performed a systematic review on studies that describe AD requiring reoperation and its subsequent mortality after anterior resection for rectal carcinoma. A systematic search was performed on published literature. Data on the definition and rate of AD, the number of ADs requiring reoperation, the mortality caused by AD, and the overall postoperative mortality were pooled and analyzed. A total of 39 studies with 24,232 patients were analyzed. The studies varied in incidence and definition of AD. Systematic review of the data showed that the overall rate of AD was 8.6%, and the rate of AD requiring reoperation was 5.4%. The postoperative mortality caused by AD was 0.4%, and the overall postoperative mortality was 1.3%. We found considerable risk and mortality for AD requiring reoperation, which largely contributed to the overall postoperative mortality.

Evidence of positive selection at codon sites localized in the C-terminal peptide of ORC6.

Origin recognition complex 6 (Orc6) plays a central role in the initiation of DNA replication in all eukaryotic systems. The exact contribution of Orc6 to replication initiation has yet to be elucidated. Here, we analyzed the evolutionary dynamics of Orc6 in 15 vertebrates. Positive selection was detected in the region of exon 6 of the Orc6 gene. Site tests revealed a proportion of codon sites that displayed evidence of positive selection (ω > 1) within the coding sequences of the vertebrate Orc6 gene. Seven positively selected amino acid sites were identified and three were located in exon6. These results suggest that amino acid residues present in the middle region of the protein are more selectively constrained, whereas amino acid residues in the C-terminal peptide of the protein evolve at a faster rate, possibly because of heightened selective pressure during the course of evolution.

Signatures of positive selection in LY96 gene in vertebrates.

As a secreted glycoprotein that binds to the extracellular domain of Toll-like receptor 4 (TLR4), Lymphocyte Antigen 96 (LY96), also called myeloid differentiation 2 (MD2), is required for the activation of TLR4 by lipopolysaccharide (LPS) and plays an important role in innate immunity, which is the first line of defence against microbial infections. Previous studies have proposed that mammalian toll-like receptors (TLRs) have evolved under diversifying selection due to their role in pathogen detection. Given the fact that LY96 is highly functionally linked to TLR4, it would be interesting to test whether LY96 is under the intense pressure of natural selection. To investigate the natural selection hypothesis, we compared the coding sequences from 13 vertebrates and evaluated the molecular evolution of LY96 gene in these species. Result shows that natural selection at exon 4 has indeed played a role in shaping the function of LY96 in the course of evolution. In addition to the study of Nakajima, we found the two branch nodes with Ka/Ks ratios greater than 1: the one leading to cow and pig and the other to rabbit and the primates.

Systematic review of anastomotic leakage rate according to an international grading system following anterior resection for rectal cancer.

BACKGROUND: A generally acceptable definition and a severity grading system for anastomotic leakages (ALs) following rectal resection were not available until 2010, when the International Study Group of Rectal Cancer (ISGRC) proposed a definition and a grading system for AL. METHODS: A search for published data was performed using the MEDLINE database (2000 to December 5, 2012) to perform a systematic review of the studies that described AL, grade AL according to the grading system, pool data, and determine the average rate of AL for each grade after anterior resection (AR) for rectal cancer. RESULTS: A total of 930 abstracts were retrieved; 40 articles on AR, 25 articles on low AR (LAR), and 5 articles on ultralow AR (ULAR) were included in the review and analysis. The pooled overall AL rate of AR was 8.58% (2,085/24,288); the rate of the asymptomatic leakage (Grade A) was 2.57%, that of AL that required active intervention without relaparotomy (Grade B) was 2.37%, and that of AL that required relaparotomy (Grade C) was 5.40%. The pooled rate of AL that required relaparotomy was higher in AR (5.40%) than in LAR (4.70%) and in ULAR (1.81%), which could be attributed to the higher rate of protective defunctioning stoma in LAR (40.72%) and ULAR (63.44%) compared with that in AR (30.11%). CONCLUSIONS: The new grading system is simple that the ALs of each grade can be easily extracted from past publications, therefore likely to be accepted and applied in future studies.

miR-30a suppresses cell migration and invasion through downregulation of PIK3CD in colorectal carcinoma.

BACKGROUND/AIMS: MicroRNAs (miRNAs) play key roles in tumor metastasis. The aim of this study was to determine the regulation and function of miR-30a in colorectal carcinoma (CRC) metastasis. METHODS: The expression of miR-30a was detected in CRC cell lines and samples by qRT-PCR. The anti-metastatic effect of miR-30a was determined by both in vitro and in vivo assays. A luciferase reporter assay was performed to determine target association between miR-30a and phosphoinositide 3-kinase catalytic subunit delta (PIK3CD). RESULTS: miR-30a was significantly downregulated in highly metastatic CRC cell lines and metastatic tissues. Overexpression of miR-30a suppressed CRC cell migration and invasion in vitro and liver metastasis in vivo, whereas miR-30a deletion dramatically promoted cell migration and invasion. Further studies revealed that PIK3CD is a direct target of miR-30a as miR-30a bounds directly to the 3'-UTR of PIK3CD, subsequently reducing its expression. Similar to the restoring miR-30a expression, PIK3CD downregulation inhibited cell migration and invasion, whereas PIK3CD overexpression rescued the suppressive effect of miR-30a. Moreover, significant downregulation of miR-30a in metastatic CRC tissues was found to be inversely correlated with PIK3CD expression. Mechanistic studies revealed that miR-30a down-regulated the expression of key components of the Akt/mTOR pathway, whereas PIK3CD overexpression reversed this negative effect. CONCLUSION: Our findings indicate that miR-30a might function as a metastasis suppressor in CRC. miR-30a may be a potential therapeutic target to block CRC metastasis.