Chronologic changes in clinical and survival features of pancreatic ductal adenocarcinoma since 2000: A single-center experience with 2,029 patients

BACKGROUND

To identify chronologic changes in clinical and survival features of pancreatic ductal adenocarcinoma based on diagnosis and treatment strategy development since 2000.

METHODS

Among 2,029 patients enrolled in this study, 746 and 1,283 were treated between 2000 and 2009 (group 1) and between 2010 and 2016 (group 2), respectively. We used patient clinicopathologic, biologic, and molecular factors to assess the prognostic factors.

RESULTS

Group 2 had a better survival outcome than group 1 (median survival time: 24.9 versus 18.4 months; 5-year survival rate: 27.6% versus 22.3%). The tendency for early diagnosis (lower CA19-9 levels, smaller size, and earlier T stage), use of neoadjuvant chemotherapy, decreased morbidity, early recovery (lesser hospital stay and more minimally invasive surgery), and standardization of surgical techniques appeared to improve patient survival. Multivariable analysis for prognosis revealed that tumor biologic factors (increased preoperative serum CA19-9 level, tumor size, tumor differentiation, N stage, and presence of lymphovascular invasion), operational factors (status of the resection margin, type of operation, and year of operation), and genetic factors (K-ras mutations) correlated with patient survival.

CONCLUSION

Early diagnosis and combined efforts, such as neoadjuvant chemotherapy and an established system of patient care, have gradually enhanced patient survival after operative resection for pancreatic ductal adenocarcinoma. Hence, multiplex prognostic parameters could provide additional information for improved prognostic estimation of pancreatic cancer exhibiting heterogeneous results.

Metformin-associated Chemopreventive Effects on Recurrence After Hepatic Resection of Hepatocellular Carcinoma: From In Vitro to a Clinical Study

BACKGROUND/AIM

We investigated metformin-induced cytotoxic effects in vitro and assessed the chemopreventive effects of metformin in patients undergoing hepatic resection (HR) for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

This study consisted of laboratory and clinical studies.

RESULTS

In vitro study using HCC cell lines revealed noticeable cytotoxic effects of metformin, that were largely weaker than those of sorafenib. In the clinical study, no statistical differences were found in tumor recurrence or overall survival between metformin and control groups. In contrast, there was a non-significant difference in tumor recurrence between metformin and propensity score-matched control groups, but there was a significant difference in overall patient survival. Metformin administration was an independent risk factor for patient survival.

CONCLUSION

In conclusion, our in vitro laboratory study demonstrated the presence of cytotoxic effects of metformin. Metformin administration was associated with reduced tumor recurrence and helped induce significant improvements in overall patient survival in patients who underwent HR for HCC.

Multiplexed gene expression profiling identifies the FGFR4 pathway as a novel biomarker in intrahepatic cholangiocarcinoma

Background

The fibroblast growth factor receptor 4 (FGFR4) pathway is an essential regulatory component of bile acid synthesis, and its relationship with hepatocellular carcinoma (HCC) has been reported. We investigated the gene expression and clinical significance of FGFR4 and related pathways in intrahepatic cholangiocarcinoma (iCCA).

Results

The median age was 56 years (range 30–78) and 34 patients (74%) were male. Six patients (13%) had hepatitis B virus infection, with or without liver cirrhosis. Overall survival was significantly associated with FGFR4 (p = 0.004), FGF19 (p = 0.047), FGF21 (p = 0.04), and KLB (p = 0.03) expression. In the multivariate analysis with potential prognostic factors, high expression of FGF19, FGF21, and FGFR4 was significantly associated with better survival. In the analysis using the TCGA iCCA dataset, mRNA overexpression of at least 1 of the FGFR4-related genes was significantly associated with better disease-free survival (p = 0.02).

Materials and Methods

We assessed the expression of 98 genes in formalin-fixed paraffin embedded tumor tissue specimens from 46 patients with surgically resected iCCA using a NanoString platform. This included 10 FGF pathway genes (e.g. FGFR1-4, KLB, FGF3, 4, 19, 21, and 23), 19 distal marker genes (e.g. CYP7A1 and CYP17A1), 31 genes relevant to HCC and iCCA (e.g. AFP, TS), 18 copy number variation matched genes, and 20 control genes. Log-transformation of gene expression was performed for normalization and statistical analysis. Overall survival was correlated with gene expression (< median vs. ≥ median) using a log-rank test. The prognostic impact of FGFR4-related genes was validated using the public TCGA dataset for iCCA.

Conclusions

Our results indicate that mRNA expression of FGFR4-related genes may be a biomarker to define the distinctive molecular phenotype of iCCA. Future preclinical and clinical validation is required to define the role of the FGFR4 pathway in iCCA.

Validation of the Eighth American Joint Committee on Cancer Staging System for Distal Bile Duct Carcinoma

PURPOSE

T category of the eighth edition of the American Joint Committee on Cancer (AJCC) staging system for distal bile duct carcinoma (DBDC) was changed to include tumor invasion depth measurement, while the N category adopted a 3-tier classification system based on the number of metastatic nodes.

Materials and Methods

To validate cancer staging, a total of 200 surgically resected DBDCs were staged and compared according to the seventh and eighth editions.

RESULTS

T categories included T1 (n=37, 18.5%), T2 (n=114, 57.0%), and T3 (n=49, 24.5%). N categories included N0 (n=133, 66.5%), N1 (n=50, 25.0%), and N2 (n=17, 8.5%). Stage groupings included I (n=33, 16.5%), II (n=150, 75.0%), and III (n=17, 8.5%). The overall 5-year survival rates (5-YSRs) of T1, T2, and T3 were 59.3%, 42.4%, and 12.2%, respectively. T category could discriminate patient survival by both pairwise (T1 and T2, p=0.011; T2 and T3, p < 0.001) and overall (p < 0.001) comparisons. The overall 5-YSRs of N0, N1, and N2 were 47.3%, 17.0%, and 14.7%, respectively. N category could partly discriminate patient survival by both pairwise (N0 and N1, p < 0.001; N1 and N2, p=0.579) and overall (p < 0.001) comparisons. The overall 5-YSRs of stages I, II, and III were 59.0%, 35.4%, and 14.7%, respectively. Stages could distinguish patient survival by both pairwise (I and II, p=0.002; II and III, p=0.015) and overall (p < 0.001) comparisons. On multivariate analyses, T and N categories (p=0.014 and p=0.029) and pancreatic invasion (p=0.006) remained significant prognostic factors.

CONCLUSION

The T andNcategories of the eighth edition AJCC staging system for DBDC accurately predict patient prognosis.

Leptin, leptin receptors and hypoxia-induced factor-1α expression in the placental bed of patients with and without preeclampsia during pregnancy

The mechanism underlying the pathogenesis of preeclampsia (PE) has been previously investigated but remains to be elucidated. Among numerous biomarkers that are associated with the pathogenesis of PE, leptin is most frequently investigated. Although studies concerning the association between PE and the expression of leptin in the serum and placenta have been conducted, the results are conflicting and inconsistent. Furthermore, the expression of leptin and its receptors in the placental bed and their association with PE, to the best of our knowledge, has not been previously reported. Therefore, to determine the association between the expression of leptin and its receptor, and pathogenesis and onset period of PE, placental bed tissues were obtained from cesarean section deliveries. The mRNA and protein expression levels of leptin and its receptor were investigated in normal pregnancies (n=18), pregnancies complicated with early‑onset PE (n=9) and late‑onset PE (n=9) by reverse transcription‑quantitative polymerase chain reaction and western blotting, respectively. The results demonstrated that the mRNA and protein expression of leptin in the placental bed was significantly increased in the PE groups compared with normal controls and was associated with the onset period of PE. Furthermore, as evidenced by immunostaining, leptin was upregulated in endothelial cells of the placental bed in the PE groups, with a particularly strong upregulation in activated endothelial cells from patients with early‑onset PE. The results of the present study indicate that altered expression of leptin in the placental bed may contribute to the pathogenesis of PE.

Improved Battery Performance of Nanocrystalline Si Anodes Utilized by Radio Frequency (RF) Sputtered Multifunctional Amorphous Si Coating Layers

Despite the high theoretical specific capacity of Si, commercial Li-ion batteries (LIBs) based on Si are still not feasible because of unsatisfactory cycling stability. Herein, amorphous Si (a-Si)-coated nanocrystalline Si (nc-Si) formed by versatile radio frequency (RF) sputtering systems is proposed as a promising anode material for LIBs. Compared to uncoated nc-Si (retention of 0.6% and Coulombic efficiency (CE) of 79.7%), the a-Si-coated nc-Si (nc-Si@a-Si) anodes show greatly improved cycling retention (C_50th/C_first) of ∼50% and a first CE of 86.6%. From the ex situ investigation with electrochemical impedance spectroscopy (EIS) and cracked morphology during cycling, the a-Si layer was found to be highly effective at protecting the surface of the nc-Si from the formation of solid-state electrolyte interphases (SEI) and to dissipate the mechanical stress upon de/lithiation due to the high fracture toughness.

Renoprotective Effects of Carbon Monoxide-Releasing Molecule 3 in Ischemia-Reperfusion Injury and Cisplatin-Induced Toxicity

BACKGROUND

We investigated the effects of a soluble carbon monoxide-releasing molecule (CORM) in cisplatin-induced cytotoxicity and ischemia-reperfusion injury (IRI) in vitro.

METHODS

The effects of CORM-3 (12.5-200 μM) were assessed in normal kidney epithelial cells (HK-2, LLC-PK1) and renal cancer cells (Caki-1, Caki-2) subjected to cisplatin (50-200 μM) or IRI. To induce IRI, cells were placed in an anaerobic chamber (37°C, 95% nitrogen, 5% carbon dioxide) for 48 hours. Cells were transferred to complete medium and incubated at 37°C, 5% carbon dioxide for 6 hours. Cell viability (CCK assays), tumor necrosis factor (TNF)-α messenger RNA (mRNA) levels (quantitative reverse-transcriptase polymerase chain reaction), and protein expression of cleaved-caspase 3 and oxidative stress markers (including Erk1/2, JNK, and P38; Western blot) were assessed.

RESULTS

Viability after IRI was approximately 40% of control. Protective effects of CORM-3 in the IRI model were dose-dependent. Cell viability was 40% recovered in 200-μM CORM-3-pretreated cells compared with control. The protective effects of CORM-3 in cells exposed to cisplatin for 24 hours were weaker than in the IRI model. TNF-α mRNA was induced by stimulated IRI or cisplatin exposure; CORM-3 pretreatment attenuated the rise in TNF-α mRNA. IRI or cisplatin-induced activated oxidative stress markers decreased in CORM-3-pretreated cells. CORM-3 reduced expression of the apoptotic marker cleaved-caspase 3.

CONCLUSION

Our data demonstrate the protective effects of CORM-3 in cisplatin cytotoxicity and IRI in both normal kidney cells and renal cancer cells in vitro. CORM-3 exerts these effects by ameliorating inflammatory and oxidative stress pathways.

Differential Expression Patterns of Irf3 and Irf7 in Pediatric Lymphoid Disorders

Interferon regulatory factors (IRFs) are multifunctional transcriptional factors. To define the role of IRFs in lymphoid disorders, we determined the expression patterns of IRF3 and IRF7 by immunohistochemistry in 5 normal lymph nodes, 12 reactive hyperplastic lymph nodes, and 27 pediatric lymphomas. IRF3 was prominently expressed in the nuclei of the histiocytes, and was expressed very weakly in the cytoplasm of most of the lymphocytes of the normal lymph nodes. However, IRF7 was expressed strongly in the nuclei of over 50% of the lymphocytes throughout the normal lymph nodes, but the histiocytes and fibroblasts were spared. In the reactive hyperplastic lymph nodes, the number of IRF3- and IRF7-positive cells in the nuclei was elevated. In the lymphomas, the number of IRF3-positive cells in the nucleus appeared to have decreased, and the cells were scattered throughout the lymphoma tissue in no specific pattern. However, in most cases the number of IRF7-positive cells was elevated.

These results suggested that IRF3 was activated principally in the histiocytes and T cells under inflammatory conditions, but IRF3 activation was attenuated in cases of lymphoma. However, the number of IRF7-positive cells was found to be elevated in the reactive hyperplastic lymph nodes and pediatric lymphoma.

Ginseng for improving semen quality parameters: A protocol of systematic review

BACKGROUND

The aim of this systematic review is to determine whether ginseng is effective in improving sperm quality.

METHODS AND ANALYSIS

Twelve databases will be searched from their inception to the present date: PubMed, EMBASE, AMED, the Cochrane Library, 5 Korean medical databases (KoreaMed, DBpia, OASIS, the Research Information Service System [RISS], and the Korean Studies Information Service System [KISS]), and 3 Chinese medical databases (China National Knowledge Infrastructure [CNKI], the Wanfang Database, and the Chinese Scientific Journals Database [VIP]). We will include all prospective clinical trials including randomized controlled trials (RCTs), controlled trials, and uncontrolled observational studies. We will exclude case study and case series, and retrospective studies in which healthy men or men with subfertility are treated with any type of ginseng. We will exclude studies comparing the 2 different forms of ginseng. The selection of the studies, data abstraction, and validations will be performed independently by 2 researchers. The risk of bias of the RCTs will be evaluated using the Cochrane's risk of bias assessment tool.

ETHICS AND DISSEMINATION

The findings will be disseminated to appropriate audiences via peer-reviewed publications and conference presentations. Our review will provide readers the opportunity to access studies originally published in East Asian languages that they would otherwise be unable to read.

TRIAL REGISTRATION NUMBER

PROSPERO 2017 CRD42017078797.

Hepatocellular Carcinoma Arising in a Huge Hepatocellular Adenoma with Bone Marrow Metaplasia

Hepatocellular adenoma (HCA) is the most common type of benign liver tumor, and its major complication is malignant transformation to hepatocellular carcinoma (HCC). Here, we report a case of HCC arising in HCA with bone marrow metaplasia in a 24-year-old Korean woman who presented with abdominal discomfort. A huge liver mass was found on abdominal ultrasonography. She underwent surgical hepatic resection, and the resected specimen was entirely involved by a 20-cm-sized tumor. Histological review revealed a well differentiated HCC arising from inflammatory HCA with β-catenin nuclear positivity and bone marrow metaplasia that contained hematopoietic cells. This case was unique because malignant transformation, inflammatory type HCA, β-catenin nuclear staining, and bone marrow metaplasia were simultaneously observed. Additionally, it should be noted that a large HCA with β-catenin activation can undergo malignant transformation and should be surgically resected in a timely manner.

Plasma indoxyl sulfate concentration predicts progression of chronic kidney disease in dogs and cats

Indoxyl sulfate is a protein-bound uremic toxin that increases as the severity of impaired renal function increases in humans, laboratory animals, dogs and cats. An elevation of indoxyl sulfate is related to prognosis among people with chronic kidney disease. However, whether indoxyl sulfate is able to predict the progression of chronic kidney disease in dogs and cats has not been previously studied. In the present study, 58 cats and 36 dogs with chronic kidney disease were enrolled. Plasma indoxyl sulfate was measured by high performance liquid chromatography. Renal progression was defined as an increase by one International Renal Interest Society (IRIS) stage and/or a rise in serum creatinine concentration of 0.5mg/dL during the same stage within a 3-month period. Compared with the non-progression groups, across different stages of renal failure, the baseline plasma indoxyl sulfate concentration was increased in the renal progression group (P<0.05), especially for IRIS stages 2 and 3 animals. The area under the receiver operator characteristic curves of indoxyl sulfate, when predicting renal progression, was above 0.75 for both dogs and cats. Indoxyl sulfate concentrations were also correlated with the increase of blood urea nitrogen, serum creatinine, and phosphate and the decrease of hematocrit among cats; while in dogs, concentrations were only correlated with the increase of phosphate concentrations. Indoxyl sulfate served as a biomarker of progression risk in dogs and cats with chronic kidney disease.

Prognostic Implication of Inflammation-based Prognostic Scores in Patients with Intrahepatic Cholangiocarcinoma Treated with First-line Gemcitabine plus Cisplatin

Background We aimed to comprehensively evaluate the prognostic value of inflammation-based prognostic scores, including the modified Glasgow Prognostic Score (mGPS), neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR), exclusively in patients with advanced intrahepatic cholangiocarcinoma (iCCA). Methods Between May 2010 and April 2015, 305 patients with histologically documented unresectable or metastatic iCCA were treated with first-line gemcitabine plus cisplatin (GemCis). Among these, 257 patients had complete data for inflammation-based prognostic scores and were included. Results Median age was 59 (range: 27-78) years, and 158 patients (61.5%) were males. High mGPS was independently associated with poor progression-free survival (PFS; mGPS ≥1 vs. 0: median, 3.9 vs. 5.5 months; P = 0.001) and overall survival (OS; mGPS ≥1 vs. 0; median, 6.9 vs. 14.1 months; P = 0.002) in the multivariate analysis. Regarding high NLR (> median) and PLR (> median), although a potential association existed with poor PFS or OS in the univariate analysis, these did not remain as significant in the multivariate analyses. Conclusion The current study suggests that mGPS might be the relevant prognostic index that could stratify the survival outcomes of patients with unresectable or metastatic iCCA who received first-line GemCis.

Oral Administration of (S)-Allyl-l-Cysteine and Aged Garlic Extract to Rats: Determination of Metabolites and Their Pharmacokinetics

(S)-Allyl-l-cysteine is the major bioactive compound in garlic. (S)-Allyl-l-cysteine is metabolized to (S)-allyl-l-cysteine sulfoxide, N-acetyl-(S)-allyl-l-cysteine, and N-acetyl-(S)-allyl-l-cysteine sulfoxide after oral administration. An accurate LC-MS/MS method was developed and validated for the simultaneous quantification of (S)-allyl-l-cysteine and its metabolites in rat plasma, and the feasibility of using it in pharmacokinetic studies was tested. The analytes were quantified by multiple reaction monitoring using an atmospheric pressure ionization mass spectrometer. Because significant quantitative interference was observed between (S)-allyl-l-cysteine and N-acetyl-(S)-allyl-l-cysteine as a result of the decomposition of N-acetyl-(S)-allyl-l-cysteine at the detector source, chromatographic separation was required to discriminate (S)-allyl-l-cysteine and its metabolites on a reversed-phase C₁₈ analytical column with a gradient mobile phase consisting of 0.1% formic acid and acetonitrile. The calibration curves of (S)-allyl-l-cysteine, (S)-allyl-l-cysteine sulfoxide, N-acetyl-(S)-allyl-l-cysteine, and N-acetyl-(S)-allyl-l-cysteine sulfoxide were linear over each concentration range, and the lower limits of quantification were 0.1 µg/mL [(S)-allyl-l-cysteine and N-acetyl-(S)-allyl-l-cysteine] and 0.25 µg/mL [(S)-allyl-l-cysteine sulfoxide and N-acetyl-(S)-allyl-l-cysteine sulfoxide]. Acceptable intraday and inter-day precisions and accuracies were obtained at three concentration levels. The method satisfied the regulatory requirements for matrix effects, recovery, and stability. The validated LC-MS/MS method was successfully used to determine the concentration of (S)-allyl-l-cysteine and its metabolites in rat plasma samples after the administration of (S)-allyl-l-cysteine or aged garlic extract.

Hypoxia induced phosphorylation of estrogen receptor at serine 118 in the absence of ligand

The estrogen receptor (ER) plays an important role in breast cancer development and progression. Hypoxia modulates the level of ERα expression and induces ligand-independent transcriptional activation of ERα, which is closely related with the biology of breast carcinomas. Since phosphorylation itself affects the transcriptional activity and stabilization of ERα, we examined changes in ERα phosphorylation under hypoxic conditions. Hypoxia induced phosphorylation of ERα at serine residue 118 (S118) in the absence of estrogen through the mitogen-activated protein kinase (MAPK)/ERK1/2 pathway. Cell proliferation was significantly decreased under normoxia or hypoxia when ERα harboring the S118A mutation was overexpressed. Our previous studies showed that ER degradation is the most prominent phenomenon under hypoxia. E2-induced ER protein downregulation is dependent on phosphorylation of S118. However, hypoxia-induced ERα degradation did not involve S118 phosphorylation. Our study implies the existence of a differential mechanism between E2 and hypoxia-mediated ERα protein degradation. Understanding the mechanistic behavior of ER under hypoxia will likely facilitate understanding of endocrine therapy resistance and development of treatment strategies for breast cancer.

YH12852, a potent and highly selective 5-HT4 receptor agonist, significantly improves both upper and lower gastrointestinal motility in a guinea pig model of postoperative ileus

BACKGROUND

Postoperative ileus (POI) is a transient gastrointestinal (GI) dysmotility that commonly develops after abdominal surgery. YH12852, a novel, potent and highly selective 5-hydroxytryptamine 4 (5-HT₄ ) receptor agonist, has been shown to improve both upper and lower GI motility in various animal studies and may have applications for the treatment of POI. Here, we investigated the effects and mechanism of action of YH12852 in a guinea pig model of POI to explore its therapeutic potential.

METHODS

The guinea pig model of POI was created by laparotomy, evisceration, and gentle manipulation of the cecum for 60 seconds, followed by closure with sutures under anesthesia. Group 1 received an oral administration of vehicle or YH12852 (1, 3, 10 or 30 mg/kg) only, while POI Group 2 was intraperitoneally pretreated with vehicle or 5-HT₄ receptor antagonist GR113808 (10 mg/kg) prior to oral dosing of vehicle or YH12852 (3 or 10 mg/kg). Upper GI transit was evaluated by assessing the migration of a charcoal mixture in the small intestine, while lower GI transit was assessed via measurement of fecal pellet output (FPO).

KEY RESULTS

YH12852 significantly accelerated upper and lower GI transit at the doses of 3, 10, and 30 mg/kg and reached its maximal effect at 10 mg/kg. These effects were significantly blocked by pretreatment of GR113808 10 mg/kg.

CONCLUSION AND INFERENCES

Oral administration of YH12852 significantly accelerates and restores delayed upper and lower GI transit in a guinea pig model of POI. This drug may serve as a useful candidate for the treatment of postoperative ileus.

Gaseous Nanocarving-Mediated Carbon Framework with Spontaneous Metal Assembly for Structure-Tunable Metal/Carbon Nanofibers

Vapor phase carbon (C)-reduction-based syntheses of C nanotubes and graphene, which are highly functional solid C nanomaterials, have received extensive attention in the field of materials science. This study suggests a revolutionary method for precisely controlling the C structures by oxidizing solid C nanomaterials into gaseous products in the opposite manner of the conventional approach. This gaseous nanocarving enables the modulation of inherent metal assembly in metal/C hybrid nanomaterials because of the promoted C oxidation at the metal/C interface, which produces inner pores inside C nanomaterials. This phenomenon is revealed by investigating the aspects of structure formation with selective C oxidation in the metal/C nanofibers, and density functional theory calculation. Interestingly, the tendency of C oxidation and calculated oxygen binding energy at the metal surface plane is coincident with the order Co > Ni > Cu > Pt. The customizable control of the structural factors of metal/C nanomaterials through thermodynamic-calculation-derived processing parameters is reported for the first time in this work. This approach can open a new class of gas-solid reaction-based synthetic routes that dramatically broaden the structure-design range of metal/C hybrid nanomaterials. It represents an advancement toward overcoming the limitations of intrinsic activities in various applications.

The effects and mechanism of action of methane on ileal motor function

BACKGROUND

Methane has been associated with constipation-predominant irritable bowel syndrome, slowing intestinal transit time by augmenting contractile activity. However, the precise mechanism underlying this effect remains unclear. Therefore, we investigated the mechanisms underlying the effect of methane on contractile activity, and whether such effects are mediated by nerve impulses or muscular contraction.

METHODS

We connected guinea pig ileal muscle strips to a force/tension transducer and measured amplitudes of contraction in response to electrical field stimulation (EFS; 1, 2, 8, 16 Hz) following methane infusion in the presence of tetradotoxin (TTX), atropine, guanethidine, or GR 113808. We then performed calcium imaging using Oregon Green 488 BAPTA-1 AM in order to visualize changes in calcium fluorescence in response to EFS following methane infusion in the presence of TTX, atropine, or a high K⁺ solution.

KEY RESULTS

Methane significantly increased amplitudes of contraction (P<.05), while treatment with TTX abolished such contraction. Methane-induced increases in amplitude were inhibited when lower-frequency (1, 2 Hz) EFS was applied following atropine infusion (P<.05). Neither guanethidine nor GR 113808 significantly altered contraction amplitudes. Methane significantly increased calcium fluorescence, while this increase was attenuated following atropine infusion (P<.05). Although calcium fluorescence was increased by the high K⁺ solution under pretreatment with TTX, the intensity of fluorescence remained unchanged after methane infusion.

CONCLUSIONS AND INFERENCES

The actions of methane on the intestine are influenced by the cholinergic pathway of the enteric nervous system. Our findings support the classification of methane as a gasotransmitter.

Prognostic effect of transarterial chemoembolization-induced complete pathological response in patients undergoing liver resection and transplantation for hepatocellular carcinoma

Transarterial chemoembolization (TACE)-induced complete pathological response (CPR) is known to improve postresection outcomes of hepatocellular carcinoma (HCC). We aimed to assess the prognostic effects of CPR after preoperative TACE for HCC in patients who underwent hepatic resection (HR) or liver transplantation (LT). The clinical outcomes of patients showing CPR after HR (n = 110) or LT (n = 233) were analyzed. The control groups comprised patients with minimal recurrence risk as naïve single HCC ≤ 2 cm for HR (n = 476), and 1 or 2 HCCs ≤ 2 cm for LT (n = 184). Among HR study patients, 1-, 3-, and 5-year tumor recurrence rates were 18.5%, 50.6%, and 58.7% respectively, which were higher than those of controls (P < 0.001). The 1-, 3-, and 5-year patient survival rates were 97.8%, 82.0%, and 69.1%, respectively, which were lower than those of controls (P < 0.001). Among LT study patients, 1-, 3-, and 5-year tumor recurrence rates were 4.1%, 7.9%, and 7.9%, respectively, which were higher than those of controls (P = 0.019). The 1-, 3-, and 5-year patient survival rates were 92.7%, 89.2%, and 86.9%, respectively, which were not different than those of controls (P = 0.11). LT recipients had lower recurrence and higher survival rates compared with HR patients (P < 0.001). The tumor recurrence site was mainly intrahepatic in HR patients. There was no difference between the incidences of extrahepatic recurrence in the HR study group and all-site recurrence in the LT study group (P = 0.61). We concluded that the prognostic effect of TACE-induced CPR for HCC patients appears to be limited to downstaging. LT recipients benefited more from CPR than HR patients. Liver Transplantation 23 781-790 2017 AASLD.

Circadian Clock Is Involved in Regulation of Hepatobiliary Transport Mediated by Multidrug Resistance-Associated Protein 2

There has been a growing interest in circadian regulation of the expression and function of drug transporters. In this study, we investigated circadian rhythm in the expression and function of multidrug resistance-associated protein 2 (Mrp2) in mouse liver and involvement of circadian clock in their regulations by using the circadian clock genes (period 1 and period 2) knockout mice. The mRNA and protein expression of Mrp2, P-glycoprotein, and breast cancer resistance protein was measured in the mouse liver at different times of the day. Circadian variation of hepatobiliary excretion of phenolsulfonphthalein, a model substrate of Mrp2, was also investigated in mice. Circadian oscillation of Mrp2 protein expression was clearly observed in the mouse liver with levels down at the light phase and up at the dark phase. The cumulative biliary excretion and biliary clearance of phenolsulfonphthalein from the liver to the bile was 2.37- and 1.74-fold greater in mice administered during the dark phase than in those administered during the light phase, respectively. The circadian oscillation in mRNA expression of Mrp2 disappeared in period 1 and period 2 double knockout mice. These results suggest that the expression and function of Mrp2 show the circadian rhythm, controlled by circadian clock genes.

Probabilistic Fatigue Life Updating for Railway Bridges Based on Local Inspection and Repair

Railway bridges are exposed to repeated train loads, which may cause fatigue failure. As critical links in a transportation network, railway bridges are expected to survive for a target period of time, but sometimes they fail earlier than expected. To guarantee the target bridge life, bridge maintenance activities such as local inspection and repair should be undertaken properly. However, this is a challenging task because there are various sources of uncertainty associated with aging bridges, train loads, environmental conditions, and maintenance work. Therefore, to perform optimal risk-based maintenance of railway bridges, it is essential to estimate the probabilistic fatigue life of a railway bridge and update the life information based on the results of local inspections and repair. Recently, a system reliability approach was proposed to evaluate the fatigue failure risk of structural systems and update the prior risk information in various inspection scenarios. However, this approach can handle only a constant-amplitude load and has limitations in considering a cyclic load with varying amplitude levels, which is the major loading pattern generated by train traffic. In addition, it is not feasible to update the prior risk information after bridges are repaired. In this research, the system reliability approach is further developed so that it can handle a varying-amplitude load and update the system-level risk of fatigue failure for railway bridges after inspection and repair. The proposed method is applied to a numerical example of an in-service railway bridge, and the effects of inspection and repair on the probabilistic fatigue life are discussed.