Effect of Autonomous Vehicles on Fatigue Life of Orthotropic Steel Decks.

The fatigue life of orthotropic steel decks (OSDs) is significantly affected by vehicle loads, and the local stress response of OSDs is sensitive to the transverse position of vehicle loads. However, the presence of autonomous vehicles is likely to change the transverse distribution of vehicles within the lane, thereby affecting vehicle-induced fatigue damage to OSDs. Therefore, it is necessary to evaluate the potential effect of autonomous vehicles on the fatigue life of OSDs so that appropriate strategies can be implemented to control the transverse positions of autonomous vehicles passing the bridge deck. To this end, fatigue damages of several typical fatigue details in a conventional OSD (COSD) and a lightweight composite OSD (LWCD) induced by vehicle loads were calculated based on finite element analysis, and their fatigue lives were evaluated based on Miner's Rule, in which different transverse distribution patterns of autonomous vehicles and their proportions in the mixed traffic flow were considered. The results indicate that fatigue lives of both the COSD and the LWCD can be negatively affected by autonomous vehicles traveling across the bridge without any constraints on the transverse distribution, especially when their proportion in the mixed traffic flow exceeds 30%. Compared to the scenario without autonomous vehicles, the fatigue damage of most fatigue details in OSDs may increase by 51% to 210% in the most unfavorable case due to the presence of autonomous vehicles. Nevertheless, it is feasible to extend the fatigue life of OSDs by optimizing the transverse distribution of autonomous vehicles. Specifically, the fatigue life of most fatigue details in the COSD could be extended by more than 86% in the most favorable case when a bimodal Gaussian distribution is adopted as the transverse distribution pattern of autonomous vehicles. Moreover, both the negative and positive effects of autonomous vehicles on the fatigue life of the COSD are more significant than those of the LWCD in most cases. The results can provide references for the maintenance of OSDs under the action of autonomous vehicles.

International expert consensus on laparoscopic pancreaticoduodenectomy.

IMPORTANCE: While laparoscopic pancreaticoduodenectomy (LPD) is being adopted with increasing enthusiasm worldwide, it is still challenging for both technical and anatomical reasons. Currently, there is no consensus on the technical standards for LPD. OBJECTIVE: The aim of this consensus statement is to guide the continued safe progression and adoption of LPD. EVIDENCE REVIEW: An international panel of experts was selected based on their clinical and scientific expertise in laparoscopic and open pancreaticoduodenectomy. Statements were produced upon reviewing the literature and assessed by the members of the expert panel. The literature search and its critical appraisal were limited to articles published in English during the period from 1994 to 2019. The Web of Science, Medline, and Cochrane Library and Clinical Trials databases were searched, The search strategy included, but was not limited to, the terms 'laparoscopic', 'pancreaticoduodenectomy, 'pancreatoduodenectomy', 'Whipple's operation', and 'minimally invasive surgery'. Reference lists from the included articles were manually checked for any additional studies, which were included when appropriate. Delphi method was used to establish expert consensus and the AGREE II-GRS Instrument was applied to assess the methodological quality and externally validate the final statements. The statements were further discussed during a one-day face-to-face meeting at the 1st Summit on Minimally Invasive Pancreatico-Biliary Surgery in Wuhan, China. FINDINGS: Twenty-eight international experts from 8 countries constructed the expert panel. Sixteen statements were produced by the members of the expert panel. At least 80% of responders agreed with the majority (80%) of statements. Other than three randomized controlled trials published to date, most evidences were based on level 3 or 4 studies according to the AGREE II-GRS Instrument. CONCLUSIONS AND RELEVANCE: The Wuhan international expert consensus meeting on LPD has produced a set of clinical practice statements for the safe development and progression of LPD. LPD is currently in its development and exploration stages, as defined by the international IDEAL framework for surgical innovation. More robust randomized controlled trial and registry study are essential to proceed with the assessment of LPD.

MicroRNA-144 suppresses cholangiocarcinoma cell proliferation and invasion through targeting platelet activating factor acetylhydrolase isoform 1b.

BACKGROUND: MicroRNAs are endogenous non-coding RNAs that play important roles in a wide variety of biological processes such as apoptosis, development, aging and cancer. The aberrant expression of miRNAs may contribute to phenotypic features of malignant cells, including resistance to chemotherapy. However, in cholangiocarcinoma (CCA) the correlation between miRNAs and their potential roles in CCA remains unclear. METHODS: MicroRNA profiles were analyzed in three pairs of CCA tumor specimens and non-tumorous-paired biliary tissues using Agilent microRNA microarrays. Expression of selected miRNAs was further confirmed in CCA tissues and CCA cell lines by q-PCR. The effects of miR-144 were evaluated by cell proliferation, migration, transwell, and tumorigenicity assays. Expression of LIS1 (platelet-activating factor acetylhydrolase isoform 1b) was assessed in CCA specimens and CCA cell lines by q-PCR and western blot. Targeting of LIS1 by miR-144 was confirmed by luciferase reporter assays. RESULTS: We found that the expression of 28 miRNAs in CCA tissues was significantly different from their corresponding adjacent normal bile duct tissues. We focused on miR-144 which was significantly down-regulated in CCA tissues. Reintroduction of miR-144 in CCA cell lines not only inhibited cell growth, but also significantly reduced cell migration and invasion capacities compared with controls. Luciferase assays and western blots verified LIS1 as a direct target of miR-144, and knocking-down LIS1 has similar effect with overexpression of miR-144 in CCA cell lines. Moreover, overexpression of miR-144 expression could suppress tumor growth in nude mice. CONCLUSIONS: Our results showed that miR-144 was reduced in CCA tissues and suggested that miR-144 may be an essential suppresser of CCA cell proliferation and invasion through targeting LIS1.

Decitabine inhibits the cell growth of cholangiocarcinoma in cultured cell lines and mouse xenografts.

Decitabine (DAC), an inhibitor of DNA methyltransferase, demonstrates antitumor activities in various types of cancer. However, its therapeutic potential for cholangiocarcinoma (CCA), one of the most aggressive gastrointestinal malignancies, remains to be explored. The present study investigated the antiproliferative effects of DAC on CCA cells in vitro and in vivo. Human CCA cell lines, TFK-1 and QBC939, were used as models to investigate DAC on the cell growth and proliferation of CCA. Cell proliferation was evaluated by Cell Counting Kit-8 assay combined with clonogenic survival assay. Flow cytometry, Hoechst 33342/propidium iodide staining and green fluorescent protein-tagged MAP-LC3 detection were applied to determine cell cycle progression, apoptosis and autophagy. Nude mice with TFK-1 xenografts were evaluated for tumor growth following DAC treatment. DAC was observed to significantly suppress the proliferation of cultured TFK-1 and QBC939 cells, accompanied with enhanced apoptosis, autophagy and cell cycle arrest at G2/M phase. In TFK-1 mouse xenografts, DAC retarded the tumor growth and increased the survival of CCA tumor-bearing mice.

Sodium valproate inhibits the growth of human cholangiocarcinoma in vitro and in vivo.

Background. None of treatment options for Cholangiocarcinoma (CCA), including surgery, adjuvant radiotherapy and chemotherapy, and ultimately liver transplantation, have been shown to substantially improve the survival rate in patients with CCA. Valproic acid (VPA), a histone deacetylase inhibitor, has been shown to display potent antitumor effects. In this study, sodium valproate, the clinically available form of VPA, was tested for its ability to inhibit the growth of cholangiocarcinoma cells, both in vitro and in vivo. Materials and Methods. Cholangiocarcinoma cells (TFK-1, QBC939, and CCLP1) of different origins were treated with sodium valproate to determine their effects on cell proliferation and differentiation, cell cycle regulation, apoptosis, and autophagy. The in vivo effects of sodium valproate on cholangiocarcinoma growth were assessed using a xenograft mouse model injected with TFK-1 cells. Results. Sodium valproate inhibited cholangiocarcinoma cell growth by inducing cell cycle arrest, cell differentiation, and apoptosis; sodium valproate effects were independent of autophagy. Tumor growth inhibition was also observed in vivo using TFK-1 xenografts. Conclusion. The in vitro and in vivo outcomes provide preclinical rationale for clinical evaluation of sodium valproate, alone or in combination with other drugs, to improve patient outcome in cholangiocarcinoma.

[Typing and surgical treatment choice for pancreatic ductal stone].

OBJECTIVE: To explore the improvement of typing and reasonable surgical treatment for pancreatic ductal stone (PDS). METHODS: Totally 89 patients with pancreatic ductul stone treated underwent surgeries from January 2000 to December 2012 were involved into this study. There were 57 male and 32 female patients, the average age was (52 ± 23) years. According to the magnetic resonance cholangiopancreatography imaging and finding during surgery, pancreatolithiasis was classified into three types: type I, the stones were located in the main pancreatic duct; type II, the stones were located both in main and branch pancreatic duct; type III, the stones were diffusely scattered in the branch pancreatic duct; the position of PDS within pancreatic parenchyma were subtitled. In this group, 43 type I PDS were extracted with endoscopic papillotomy or endoscopic pancreatic sphincterotomy, or pancreatolithotomy plus pancreato-jejunal lateral anastomosis with wide anastomotic stoma; 39 type II cases were treated by pancreatolithotomy plus pancreato-jejunal lateral anastomosis or/and resection of pancreatic section; 7 type III PDS were managed with resection of pancreatic section. RESULTS: All surgeries were performed successfully. Among complications, 6 cases (6.7%) were pancreatic leakage which recovered after systematic non-surgical treatment, 2 cases (2.2%) were anastomotic bleeding which led to 1 death, 6 cases (6.7%) were residual pancreatolithiasis in branch pancreatic duct type. Seventy-eight patients were followed up for 6 to 131 months, 57 cases were still alive so far. Five cases were intermittent abdominal pain, 7 cases were diabetes resulted from 2 subtotal pancreatectomy and 5 distal pancreatectomy, 5 cases occurred pancreatolithiasis recurrence and 3 underwent secondary surgeries. CONCLUSIONS: The basis of this modified typing of pancreatolithiasis is the position of stone in pancreatic duct rather than pancreas parenchyma. It is more important and valuable for surgical principle of taking stones out completely and maintaining pancreatic function.

Efficacy of gemcitabine plus platinum agents for biliary tract cancers: a meta-analysis.

The objective of this study was to carry out a meta-analysis of the efficacy of gemcitabine+platinum agent regimens in the treatment of advanced biliary tract cancer (BTC). PubMed and Google Scholar were searched using the following combination of search terms: gemcitabine, oxaliplatin, cholangiocarcinoma, biliary, gallbladder, bile duct. Studies were eligible for inclusion in the meta-analysis if they were randomized trials on the use of gemcitabine plus a platinum agent for the treatment of advanced (unresectable or metastatic cancer) BTC. Outcomes of interest were response rate, overall survival, and progression-free survival. Pooled odds ratios/differences in median survival and 95% confidence intervals (CIs) were determined for each outcome. A total of 47 records were identified in the initial search. Ultimately, three open-label randomized trials (two phase 2 and one phase 3) met the eligibility criteria and were included in the meta-analysis. Two studies compared gemcitabine plus cisplatin with gemcitabine alone, whereas the other study compared gemcitabine plus oxaliplatin with fluorouracil-folinic acid. The total number of patients in the studies ranged from 54 to 410. The overall analyses revealed that all survival outcomes assessed were significantly more favorable for patients treated with gemcitabine plus platinum agents than for patients not treated with this combination. Response rates: odds ratio=2.639, 95% CI=1.210-5.757, Z=2.439, P=0.015; pooled difference in median overall survival=3.822 months, 95% CI=1.798-5.845 months, Z=3.702, P<0.001; pooled difference in median progression-free survival=3.268 months, 95% CI=1.996-4.541 months, Z=5.035, P<0.001. Patients with advanced BTC who are treated with gemcitabine plus platinum agents may experience better survival outcomes compared with patients who are not treated with this combination of chemotherapy.

Emodin regulating excision repair cross-complementation group 1 through fibroblast growth factor receptor 2 signaling.

AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 µmol/L emodin to HepG2/oxaliplatin (OXA) cells, the inhibition rate (IR), 50% inhibitory concentration (IC50) and reversal index (IC50 in experimental group/IC50 in control group) were calculated. For HepG2, HepG2/OXA, HepG2/OXA/T, each cell line was divided into a control group, OXA group, OXA + fibroblast growth factor 7 (FGF7) group and OXA + emodin group, and the final concentrations of FGF7, emodin and OXA in each group were 5 ng/mL, 10 µg/mL and 10 µmol/L, respectively. Single-cell gel electrophoresis was conducted to detect DNA damage, and the fibroblast growth factor receptor 2 (FGFR2), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and excision repair cross-complementing gene 1 (ERCC1) protein expression levels in each group were examined by Western blotting. RESULTS: Compared with the IC50 of 120.78 µmol/L in HepG2/OXA cells, the IC50 decreased to 39.65 µmol/L after treatment with 10 µmol/L emodin; thus, the reversal index was 3.05. Compared with the control group, the tail length and Olive tail length in the OXA group, OXA + FGF7 group and OXA + emodin group were significantly increased, and the differences were statistically significant (P < 0.01). The tail length and Olive tail length were lower in the OXA + FGF7 group than in the OXA group, and this difference was also statistically significant. Compared with the OXA + FGF7 group, the tail extent, the Olive tail moment and the percentage of tail DNA were significantly increased in the OXA + emodin group, and these differences were statistically significant (P < 0.01). In comparison with its parental cell line HepG2, the HepG2/OXA cells demonstrated significantly increased FGFR2, p-ERK1/2 and ERCC1 expression levels, whereas the expression of all three molecules was significantly inhibited in HepG2/OXA/T cells, in which FGFR2 was silenced by FGFR2 shRNA. In the examined HepG2 cells, the FGFR2, p-ERK1/2 and ERCC1 expression levels demonstrated increasing trends in the OXA group and OXA + FGF7 group. Compared with the OXA group and OXA + FGF7 group, the FGFR2, p-ERK1/2, and ERCC1 expression levels were significantly lower in the OXA + emodin group, and these differences were statistically significant. In the HepG2/OXA/T cell line that was transfected with FGFR2 shRNA, the FGFR2, p-ERK1/2 and ERCC1 expression levels were significantly inhibited, but there were no significant differences in these expression levels among the OXA, OXA + FGF7 and OXA + emodin groups. CONCLUSION: Emodin markedly reversed OXA resistance by enhancing OXA DNA damage in HepG2/OXA cells, and the molecular mechanism was related to the inhibitory effect on ERCC1 expression being mediated by the FGFR2/ERK1/2 signaling pathway.

The fibroblast growth factor receptor 2-mediated extracellular signal-regulated kinase 1/2 signaling pathway plays is important in regulating excision repair cross-complementary gene 1 expression in hepatocellular carcinoma.

Excision repair cross-complementary gene 1 (ERCC1) is a downstream regulatory target of fibroblast growth factor receptor 2 (FGFR2); however, the mechanism of its action has not been elucidated. The cascades downstream of FGFR2 include the PKC, Ras/Raf/MEK/ERK, JAK/STAT and PI3K pathways. ERCC1 is considered to be a closely related downstream target gene of extracellular signal-regulated kinase (ERK)1/2, since ERCC1 mRNA and protein levels may be inhibited by the ERK inhibitor U0126. It was hypothesized that FGFR2, which specifically binds with fibroblast growth factor 7 (FGF7), may regulate ERCC1 gene expression through the ERK signaling pathway. The aim of the present study was to explore the association between the regulatory effect of FGFR2 on ERCC1 gene expression and the p-ERK1/2 signaling pathway in a drug-resistant hepatocellular carcinoma (HCC) cell line. The drug-resistant cell line HepG2/OXA and its parental cell line HepG2 were transfected with Bek shRNA in the logarithmic growth phase. Transfected and untransfected HepG2 and HepG2/OXA cells were then stimulated with FGF7 and changes in the protein expression of FGFR2, p-ERK1/2 and ERCC1 was detected with western blot analysis. Following transfection, HepG2/T and HepG2/OXA/T cells were observed to grow stably in a screening medium containing puromycin. The western blot analysis demonstrated a significant decrease in the protein expressions of FGFR2, p-ERK1/2 and ERCC1 in HepG2/T and HepG2/OXA/T cells as compared to untransfected cells. Expression of FGFR2, p-ERK1/2 and ERCC1 in HepG2/OXA cells was significantly increased compared to the parental HepG2 cells. Following stimulation with FGF7, the expression of FGFR2, p-ERK1/2 and ERCC1 was increased, with significant differences between HepG2 and HepG2/OXA cells in the expression of p-ERK1/2 and ERCC1. No differences were detected in the protein levels following Bek shRNA transfection in HepG2/T and HepG2/OXA/T cells. In conclusion, the FGFR2-mediated ERK1/2 signaling pathway in HCC cells plays an important role in the regulation of ERCC1 expression.

Mutual regulation between microRNA-373 and methyl-CpG-binding domain protein 2 in hilar cholangiocarcinoma.

AIM: To investigate the reciprocal modulation between microRNA (miRNA) and DNA methylation via exploring the correlation between miR-373 and methyl-CpG-binding domain protein (MBD)2. METHODS: MiR-373 expression was examined using the TaqMan miRNA assay. Methylation of miR-373 was investigated using methylation-specific polymerase chain reaction, and recruitment of methyl binding proteins was studied using the chromatin immunoprecipitation assay. Mutation analysis was conducted using the QuikChange™ Site-Directed Mutagenesis kit. The activity of miR-373 gene promoter constructs and targeting at MBD2-three prime untranslated region (3'UTR) by miR-373 were evaluated by a dual-luciferase reporter gene assay. RESULTS: In hilar cholangiocarcinoma, miR-373 decreased and was closely associated with poor cell differentiation, advanced clinical stage, and shorter survival. The promoter-associated CpG island of miR-373 gene was hypermethylated and inhibited expression of miR-373. MBD2 was up-regulated and enriched at the promoter-associated CpG island of miR-373. Methylation-mediated suppression of miR-373 required MBD2 enrichment at the promoter-associated CpG island, and miR-373 negatively regulated MBD2 expression through targeting the 3'UTR. CONCLUSION: MiR-373 behaves as a direct transcriptional target and negative regulator of MBD2 activity through a feedback loop of CpG island methylation.

Identification of methylation profile of HOX genes in extrahepatic cholangiocarcinoma.

AIM: To identify methylation profile and novel tumor marker of extrahepatic cholangiocarcinoma (CCA) with high throughout microarray. METHODS: Differential methylation profile was compared between normal bile duct epithelial cell lines and CCA cell lines by methyl-DNA immunoprecipitation (MeDIP) microarray. Bisulfite-polymerase chain reaction (BSP) was performed to identify the methylated allels of target genes. Expression of target genes was investigated before and after the treatment with DNA demethylating agent. Expression of candidate genes was also evaluated by immunofluorescence in 30 specimens of CCA tissues and 9 normal bile duct tissues. RESULTS: Methylation profile of CCA was identified with MeDIP microarray in the respects of different gene functions and signaling pathways. Interestingly, 97 genes with hypermethylated CpG islands in the promoter region were homeobox genes. The top 5 hypermethylated homeobox genes validated by BSP were HOXA2 (94.29%), HOXA5 (95.38%), HOXA11 (91.67%), HOXB4 (90.56%) and HOXD13 (94.38%). Expression of these genes was reactivated with 5'-aza-2'-deoxycytidine. Significant expression differences were found between normal bile duct and extrahepatic CCA tissues (66.67%-100% vs 3.33%-10%). CONCLUSION: HOXA2, HOXA5, HOXA11, HOXB4 and HOXD13 may work as differential epigenetic biomarkers between malignant and benign biliary tissues.

Characterization of 9-nitrocamptothecin liposomes: anticancer properties and mechanisms on hepatocellular carcinoma in vitro and in vivo.

BACKGROUND: Hepatocellular carcinoma (HCC) is the third most common cause of cancer related mortality worldwide. 9-Nitrocamptothecin (9NC) is a potent topoisomerase-I inhibitor with strong anticancer effect. To increase the solubility and stability, we synthesized a novel 9NC loaded liposomes (9NC-LP) via incorporating 9NC into liposomes. In the present study, we determined the effects of 9NC and 9NC-LP on in vitro and in vivo, and the underlying mechanisms. METHODOLOGY/PRINCIPAL FINDINGS: We first analyzed the characteristics of 9NC-LP. Then we compared the effects of 9NC and 9NC-LP on the proliferation and apoptosis of HepG2, Bel-7402, Hep3B and L02 cells in vitro. We also investigated their anticancer properties in nude mice bearing HCC xenograft in vivo. 9NC-LP has a uniform size (around 190 nm) and zeta potential (∼-11 mV), and exhibited a steady sustained-release pattern profile in vitro. Both 9NC and 9NC-LP could cause cell cycle arrest and apoptosis in a dose-dependent and p53-dependent manner. However, this effect was not ubiquitous in all cell lines. Exposure to 9NC-LP led to increased expression of p53, p21, p27, Bax, caspase-3, caspase-8, caspase-9 and apoptosis-inducing factor, mitochondrion-associated 1 and decreased expression of Bcl-2, cyclin E, cyclin A, Cdk2 and cyclin D1. Furthermore, 9NC-LP exhibited a more potent antiproliferative effect and less side effects in vivo. Western blot analysis of the xenograft tumors in nude mice showed similar changes in protein expression in vivo. CONCLUSIONS/SIGNIFICANCE: In conclusion, 9NC and 9NC-LP can inhibit HCC growth via cell cycle arrest and induction of apoptosis. 9NC-LP has a more potent anti-tumor effect and fewer side effects in vivo, which means it is a promising reagent for cancer therapy via intravenous administration.

Cytotoxicity of Triptolide and Triptolide loaded polymeric micelles in vitro.

Triptolide (TP), a diterpenoid triepoxide purified from the Chinese herb Tripterygium wilfordii Hook F is characterized by strong anti-tumor effects on various cancer cells. Except its anti-tumor effects, TP also shows multiple pharmacological side activities, such as anti-inflammatory, immune-suppressive and male anti-fertility. In order to reduce these side effects, especially the immuno-suppressive activity when used to cure cancer, a novel polymeric micelle system containing TP (TP-PM) was constructed. The immune-modulation effects of TP-PM have been evaluated by previous studies. In this study, we compared the cytotoxicity of TP and TP-PM on Jurkat and HT29 cells. Therefore, we determined the cell viability, membrane integrity, cell proliferation, apoptosis, and caspase 3/7 activity after exposure to TP and TP-PM. The results demonstrated that actually low concentrated TP and TP-PM could induce an inhibition of cell growth and proliferation as well as membrane damage in both tumor cell lines. TP and TP-PM induced apoptosis and caused activation of caspase 3/7 even at low concentrations. Both formulations destroyed the membrane of Jurkat cells, nevertheless, TP-PM showed stronger pernicious effects. In general, TP-PM induced in both tested cell lines stronger effects than TP. Therefore, polymeric micelles can be considered as promising carriers for TP in cancer therapy.

miR-373 negatively regulates methyl-CpG-binding domain protein 2 (MBD2) in hilar cholangiocarcinoma.

BACKGROUND: microRNAs (miRNAs) are a class of non-coding, single-stranded RNA molecules that regulate gene expression at the posttranscriptional level. Methyl-CpG-binding domain proteins (MBPs) are transcription repressors through binding to methylated gene promoters. Recent studies have shown that the effect of miRNAs on DNA methylation by targeting DNA methyltransferase (DNMTs) and/or MBPs plays an important role in various human cancers. AIMS: This study focuses on the regulation of MBPs by miR-373 and its downstream effect in hilar cholangiocarcinoma. METHODS: miR-373 was investigated by TaqMan miRNA Assay; mRNA and protein of MBD1, MBD2, and Mecp2 were determined by QuantiTect(®) Primer Assays and Western blotting, respectively; RASSF1A mRNA was measured by SYBR-Green real-time PCR; The targeting at MBD2-3'UTR by miR-373 was evaluated by dual-luciferase reporter gene assay. RESULTS: miR-373 decreased and closely associated with poor cell differentiation, advanced clinical stage, and shorter survival in hilar cholangiocarcinoma; MBD2 exclusively over-expressed and reciprocally related to miR-373; precursor miR-373 inhibited the luciferase activity of MBD2-3'UTR construct; exogenous miR-373 suppressed the expression of MBD2 and enhanced RASSF1A mRNA in QBC(939) cells; anti-miR-373 inhibitor up-regulated the expression of MBD2 and reduced RASSF1A mRNA in HIBEpic cells. CONCLUSIONS: miR-373 is one negative regulator of MBD2. In hilar cholangiocarcinoma, down-expression of miR-373 leads to increase of MBD2, which in turn suppresses the methylation-mediated gene such as RASSF1A.

Methyl-CpG binding protein MBD2 is implicated in methylation-mediated suppression of miR-373 in hilar cholangiocarcinoma.

Aberrant expression of miRNAs is associated with particular cancers showing tissue- and clinical-feature-specificity patterns. Some miRNA genes harboring or being embedded in CpG islands undergo methylation mediated silencing. MBP, methyl CpG binding protein, suppresses transcription through binding to methylated CpG dinucleotides. Expression of miR-373 has been reported to be suppressed in malignant bile duct cell lines. Bioinformatic prediction reveals that the transcription start site (TSS) of miR-373 is implanted in a 402 bp canonical CpG island containing 26 CpG dinucleotides. In this study, we aim to determine the epigenetic regulation of miR-373 gene in hilar cholangiocarcinoma. Taqman microRNA assay shows that down-regulation of miR-373 is closely associated with poor cell differentiation, advanced clinical stage and shorter overall and disease-free survival in hilar cholangiocarcinomas. Methylation analysis shows that the promoter-associated CpG island is hypermethylated which is consistent with the inhibition of miR-373. Chromatin immunoprecipitation (ChIP) assay indicates that down-regulation of miR-373 results from the selective recruitment of MBD2 to methylated CpG islands. In contrast, MBD2 knock-down by use of a specific siRNA promoted the expression of miR-373. Reactivation of miR-373 by pharmacologic induction of 5-aza-CdR and trichostatin A (TSA) led to decreased enrichment of MBD2 at CpG island regions. Enhanced expression of exogenous MBD2 in stable QBC939 cells which stably express pGL4-m373-prom induces strengthened recruitment of MBD2. Our findings suggest that miR-373 is a methylation-mediated gene and the implication of MBD2 in methylation-mediated suppression of miR-373 plays an important role in tumourigenesis and development in hilar cholangiocarcinoma.

[Effect of protecting parathyroid in situ in the operation of total thyroidectomy].

OBJECTIVE: To evaluate the effect of protecting parathyroid glands in situ in the operation of total thyroidectomy by detecting parathyroid hormone after the operation. METHODS: In the surgical team, 1019 consecutive patients with thyroid diseases were treated with total thyroidectomy. During the operation, parathyroid glands were protected in situ with correctly identifying the parathyroid glands, precisely dissecting its envelope and protecting its blood supply. Serum calcium level and parathyroid hormone were measured before and 24 hours after operation. The patients who had symptomatic hypocalcemia or hypoparathyroidism were given supportive treatment and followed-up. RESULTS: At least one of the parathyroid glands was preserved and remained in situ in all cases. Eighty-nine cases (8.7%) had decreased parathyroid hormone levels and 42 cases (4.1%) had complicated symptomatic hypocalcemia. The symptoms of hypocalcemia in all these cases could be controlled by supportive treatment, and serum calcium level and parathyroid hormone had all recovered 1 - 6 months later. If 3 and 4 parathyroid were conserved in situ, the postoperative complication rate was significantly lower than those with 1 and 2 parathyroid conserved (decreased PTH 69/999 vs 20/20, symptoms of hypocalcemia 25/999 vs 17/20, all P < 0.01). CONCLUSION: The techniques to protect parathyroid glands in situ are effective measure to prevent the postoperative hypoparathyroidism in total thyroidectomy.

[Conservative therapy in the treatment of cervical chylous leakage].

OBJECTIVE: To explore and evaluate the combined conservative managements in the treatment of cervical chylous leakage. METHODS: Thirty nine cases of cervical chylous leakage from June 1992 to June 2008 were retrospectively analyzed in this hospital. All of the 39 cases were cured by treating with conservative individualized therapy, including the applying of diet with high calorie, high protein and low fat and fatty food should only contains medium-chain triglycerides, total parenteral nutrition, keep the balance of hydrogen and electrolyte and correct hypoproteinemia, local pressure dressing, high persistent vacuum drainage (-50 approximately -80 kPa) and/or somatostatin analogue. RESULTS: All the cases of chylous leakage happened 2nd to 5th days after the operation. Among the 39 cases, 7 were high flow (drainage>or=500 ml/d) chylous leakage, the amount of drainage reached as high as 1440 ml per day. The time of chylous leakage closure was 3 approximately 12 days, and the mean time was 7 days. No one experienced re-operation, wound hydrops or wound infection. CONCLUSIONS: The conservative individualized therapy may play a key role in the treatment of cervical chylous leakage.

Expression of P-aPKC-iota, E-cadherin, and beta-catenin related to invasion and metastasis in hepatocellular carcinoma.

OBJECTIVES: Atypical protein kinase C iota (aPKC-iota) and its associated intracellular molecules, E-cadherin and beta-catenin, are important for cell polarization in tumorigenesis and progression. Expression of aPKC-iota, P-aPKC-iota (activated aPKC-iota), E-cadherin, and beta-catenin in hepatocellular carcinoma (HCC) was measured, and correlation with clinicopathological characteristics of HCC was analyzed. METHODS: Paraffin-embedded tumor tissue was obtained from patients with HCC after resection without preoperative radiotherapy or chemotherapy. Gene expression was detected by polymerase chain reaction (PCR), and protein expression was detected by immunohistochemistry and Western blot analysis. Expressions of aPKC-iota, P-aPKC-iota, E-cadherin, and beta-catenin were analyzed with relation to the clinicopathological data. RESULTS: The gene and protein expression of aPKC-iota are obviously higher in HCC tissues than that in peritumoral tissues and normal tissues by semiquantitative PCR and immunohistochemistry methods. Accumulation of aPKC-iota in HCC cytoplasm and nucleolus inhibited the later formation of belt-like adherens junctions (AJs) and/or tight junctions (TJs) in cell-cell contact. E-cadherin was reduced and accumulation of cytoplasm beta-catenin was increased in HCC. The expression of aPKC-iota was closely related to pathological differentiation, tumor size, invasion, and metastasis of HCC. CONCLUSION: Accumulation of cytoplasm aPKC-iota may reflect pathological differentiation, invasion, and metastasis potential of HCC. In this regard, our study on HCC revealed the potential usefulness of aPKC-iota, E-cadherin, and beta-catenin as a prognostic marker, closely related to pathological differentiation, invasion, metastasis, and prognosis of HCC.

Significance and expression of atypical protein kinase C-iota in human hepatocellular carcinoma.

BACKGROUND AND OBJECTIVE: Previous studies have indicated that abnormal expression of atypical protein kinase C (aPKC-iota) plays a critical role in occurrence and progression of malignant tumor. This study analyzed the correlation of aPKC-iota with clinicopathology in hepatocarcinoma and Cyclin E and investigated molecular mechanisms of invasion and metastasis of hepatocellular carcinoma. MATERIALS AND METHODS: The expression of the aPKC-iota gene was examined by reverse transcription-polymerase chain reaction in 7 specimens of normal liver tissues and 43 of hepatoma and adjacent tissues. Expression of aPKC-iota and Cyclin E protein was detected using immunohistochemistry and Western blot. Finally, we analyzed the correlation of aPKC-iota with clinicopathologic characteristics and invasion of hepatoma. RESULTS: The expression value (0.844 +/- 0.315) of aPKC-iota gene is obviously higher in hepatoma than the value (0.530 +/- 0.217) in adjacent tissues and the value (0.372 +/- 0.130) in normal tissue (P = 0.009). The positive expression rate (58.1%) of aPKC-iota protein in hepatoma is remarkably higher than the rate (23.3%) of adjacent tissues. The expression of aPKC-iota has a positive correlation with the expression of Cyclin E, differentiation degree, and invasion of tumor (P < 0.05). CONCLUSIONS: Differentiation degree and invasion of hepatoma are related to the expression of aPKC-iota, which plays an important role in invasion and metastasis of hepatoma.

[Prevention and cure of the complications after radical pancreatoduodenectomy].

OBJECTIVE: To investigate the causes and the measures of prevention and cure of the dangerous complications (bleeding, pancreatic fistula, biliary fistula and death) after radical pancreatoduodenectomy (RPD) for periampullary malignant tumor. METHODS: The rate and management of dangerous complications of 156 cases with RPD which were continuous performed by Department of Biliary-Pancreatic Surgery, Affiliated Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology between January 2006 and June 2008 were analyzed retrospectively, including 97 males and 59 females with 37 - 79 years old, the mean age was 56.9 years old. RESULTS: Among the 156 cases with RPD, four patients had massive hemorrhage of gastrointestinal tract due to stress ulcer, two patients had bleeding in the pancreas-intestinal anastomosis after the operation, the rate of postoperative bleeding was 3.9% (6/156). One patient with massive hemorrhage of gastrointestinal tract due to stress ulcer had severe pulmonary infection and ARDS, and died of respiratory failure finally (the overall mortality rate was 0.7%) after ICU for two months. One patients with bleeding in the pancreas-intestinal anastomosis had pancreatic fistula (the rate of pancreatic fistula was 0.7%) 3 days after the second laparotomy to open the jejunum of the pancreas-intestinal anastomosis and make a transfixion of the bleeding points in the stump. Another patient who had the tumor located in the inferior segment of the bile common duct had biliary fistula 11 days after the operation (the rate of biliary fistula was 0.7%). Two patients with fistula had good recovery by expectant treatment of ultrasound-guided puncture and drainage. CONCLUSIONS: Prompt and effective treatment of the complications of bleeding, pancreatic fistula, biliary fistula could maximally decrease the perioperative death rate.