Incidence and risk factors for postoperative common bile duct stones in patients undergoing endoscopic extraction and subsequent cholecystectomy.

BACKGROUND AND AIMS: In patients who undergo cholecystectomy after endoscopic common bile duct (CBD) stone extraction, CBD stones found postoperatively could be problematic. This study aimed to investigate the incidence and risk factors of postoperative CBD stones after cholecystectomy. METHODS: A total of 278 patients (mean age, 59.2 years; 71 men [51.1%]) who underwent endoscopic removal of CBD stones followed by cholecystectomy from January 2013 to December 2017 were included. An endoscopic nasobiliary drainage (ENBD) tube was placed immediately after endoscopic clearance of the CBD stones in all patients until cholecystectomy. An ENBD tubogram was obtained in all patients to determine the presence of postoperative CBD stones. RESULTS: Postoperative CBD stones were detected in 20.1% (56/278). An ENBD tubogram was obtained after an average of 2.42 days postoperatively. Based on univariate analysis, the statistically significant risk factors for postoperative CBD stone were CBD stones >2, CBD stone size >10 mm, cholesterol stone, maximum diameter of CBD >15 mm, treatment with endoscopic sphincterotomy alone, and use of endoscopic mechanical lithotripsy (EML). In multivariate analysis, cholesterol stone, CBD stones >2, CBD stone size >10 mm, and EML were related to postoperative CBD stones after cholecystectomy. CONCLUSIONS: Based on the relatively high rate of postoperative CBD stones after cholecystectomy, careful follow-up should be considered in patients with high-risk factors to detect CBD stones early.

Interaction of a dengue virus NS1-derived peptide with the inhibitory receptor KIR3DL1 on natural killer cells.

Killer immunoglobulin-like receptors (KIRs) interact with human leucocyte antigen (HLA) class I ligands and play a key role in the regulation and activation of NK cells. The functional importance of KIR-HLA interactions has been demonstrated for a number of chronic viral infections, but to date only a few studies have been performed in the context of acute self-limited viral infections. During our investigation of CD8(+) T cell responses to a conserved HLA-B57-restricted epitope derived from dengue virus (DENV) non-structural protein-1 (NS1), we observed substantial binding of the tetrameric complex to non-T/non-B lymphocytes in peripheral blood mononuclear cells (PBMC) from a long-standing clinical cohort in Thailand. We confirmed binding of the NS1 tetramer to CD56(dim) NK cells, which are known to express KIRs. Using depletion studies and KIR-transfected cell lines, we demonstrated further that the NS1 tetramer bound the inhibitory receptor KIR3DL1. Phenotypical analysis of PBMC from HLA-B57(+) subjects with acute DENV infection revealed marked activation of NS1 tetramer-binding natural killer (NK) cells around the time of defervescence in subjects with severe dengue disease. Collectively, our findings indicate that subsets of NK cells are activated relatively late in the course of acute DENV illness and reveal a possible role for specific KIR-HLA interactions in the modulation of disease outcomes.

Synthesis of indolyl-3-acetonitrile derivatives and their inhibitory effects on nitric oxide and PGE2 productions in LPS-induced RAW 264.7 cells.

Arvelexin is one of major constituents of Brassica rapa that exerts anti-inflammatory activities. Several indolyl-3-acetonitrile derivatives were synthesized as arvelexin analogs and evaluated for their abilities to inhibit NO and PGE2 productions in LPS-induced RAW 264.7 cells. Of the indolyl-3-acetonitriles synthesized, compound 2k, which possesses a hydroxyl group at C-7 position of the indole ring and an N-methyl substituent, more potently inhibited NO and PGE2 productions and was less cytotoxic than arvelexin on macrophage cells.

[Two cases of toxic hepatitis caused by arrowroot juice].

Herbal remedies and health foods are widely used, and their side effects have been reported. We describe two cases of symptomatic toxic hepatitis that developed in middle-aged women after ingesting arrowroot juice. The clinical manifestations were nausea, vomiting, and jaundice. The diagnosis of toxic hepatitis was made using the Roussel Uclaf Causality Assessment Method score on the basis of the patient's history and laboratory data. After supportive care, the patients showed rapid improvements of clinical symptoms, laboratory findings, and liver stiffness. Clinicians should be aware that the consumption of arrowroot juice can cause toxic hepatitis.

[A case of advanced hepatocellular carcinoma with portal vein tumor invasion controlled by percutaneous ethanol injection therapy].

Portal vein invasion is a grave prognostic indicator in the setting of hepatocellular carcinoma (HCC). There is currently no effective method for preventing the invasion of HCC into the main portal vein. We report here a case of advanced HCC with portal vein tumor thrombosis that was effectively treated with percutaneous ethanol injection (PEI), having previously enabled subsequent successive transarterial chemoembolization (TACE). A 60-year-old male patient was diagnosed with a huge HCC, based on computed tomography and angiographic findings. Despite two sessions of TACE, the tumor invaded the right portal vein. PEI was performed on the malignant portal vein thrombosis, and three sessions thereof reduced the extent of tumor thrombi in the portal vein. Successive TACEs were performed to treat the HCC in the hepatic parenchyma. The patient was still living 19 months after the first PEI with no evidence of tumor recurrence, and his liver function remained well preserved.

[A case of systemic amyloidosis with pancreatic involvement mimicking autoimmune pancreatitis].

Systemic amyloidosis is a disorder characterized by extracellular deposition of amyloid in various organs and tissues including the kidney, heart, and liver. However, pancreatic involvement is rare, and has not been reported in Korea. Systemic amyloisosis involving pancreas needs to be differentiated from several pancreatic diseases because of diffuse pancreatic enlargement and partial stricture or obstruction of main pancreatic duct. Recently, we experienced a 60-year old man who was suspected as autoimmune pancreatitis or infiltrative disorders on imaging studies, and finally diagnosed as systemic amyloidosis involving pancreas and liver on biopsy examination. We report the case with review of the relevant literatures.

PTEN modulates insulin-like growth factor II (IGF-II)-mediated signaling; the protein phosphatase activity of PTEN downregulates IGF-II expression in hepatoma cells.

The PTEN gene (phosphatase and tensin homologous on chromosome 10) is frequently mutated or deleted in a number of malignancies including human hepatocellular carcinoma (HCC). We reported previously that the hepatitis B virus X (HBx) protein, known to be a causative agent in the formation of HCC, activates insulin-like growth factor II (IGF-II) expression through Sp1 phosphorylation by protein kinase C (PKC) or mitogen-activated protein kinase (MAPK) signaling. In this report we demonstrate that the PTEN effect on HBx induced IGF-II activation in a hepatoma cell line. Expression of PTEN and IGF-II was inversely related in different hepatoma cell lines. PTEN expression induced decreased Sp1 DNA binding by dephosphorylating Sp1 and interfered with transcriptional transactivation of IGF-II by HBx in hepatoma cells. The protein phosphatase activity was involved in PTEN downregulation of IGF-II transcription through downregulation of MAPK, MAPK kinase phosphorylation and PKC translocation. Our data suggest that PTEN blocks Sp1 phosphorylation in response to HBx, by inactivating PKC, MAPK and MAPK kinase which eventually downregulate IGF-II expression, during the formation of HCC.

Activation of insulin-like growth factor II signaling by mutant type p53: physiological implications for potentiation of IGF-II signaling by p53 mutant 249.

The aim of the present study was to investigate the intracellular mediators of the third base mutant of codon 249 in p53 gene (p53mt249) mutation that potentiate IGF-II dependent IGF-I receptor (IGF-IR) signaling. p53mt249 enhanced IGF-II dependent IGF-IR signaling in p53 negative Hep3B hepatoma cells which were specifically prevented by IGF-IR antibody, alpha IR3 and lovastin. p53mt249 increased the number of IGF-II binding sites with no change in the affinity of IGF-IR. Enhanced levels of IGF-IR expression and transcription were identified in p53mt249 transfected Hep3B cells. Pre-transfection of cultured hepatoma cells with p53mt249 resulted in a three to fourfold increase in IGF-IR phosphorylation and downstream mediator IRS-I phosphorylation but, enhanced more than 15-fold after IGF-II treatment, which coincides well with the cell growth and thymidine uptake results. Our results showed that p53mt249 modulate IGF-II dependent IGF-IR signaling by upregulating IGF-IR and potentiating IGF-IRs where IGF-IRs became more sensitive on treatment with IGF-II. We concluded that p53mt249 stimulates IGF-II dependent IGF-IR signaling by upregulating the expression of both ligand (IGF-II) and receptor (IGF-IR) through an autocrine and/or paracrine loop and we outline the physiological significance of potentiation of IGF-IR by p53 mutation in the development of hepatocellular carcinoma (HCC).

[A case of chronic gastrointestinal bleeding from a Meckel's diverticulum detected by wireless capsule endoscopy].

Meckel's diverticulum is an embryonic derivative of the omphalomesenteric duct and the most commonly encountered congenital anomaly of the gastrointestinal tract. Its incidence records about 2%. Among them, only 5% are symptomatic with complications-bleeding, intestinal obstruction, inflammation, and perforation. In particular, bleeding is a common complication and has always been caused by an ulceration of the ileal mucosa adjacent to the acid-producing ectopic mucosa in a Meckel's diverticulum. Wireless capsule endoscopy is a new method enabling non-invasive diagnostic endoscopy of the entire small intestine. We experienced a case of Meckel's diverticulum detected by wireless capsule endoscopy in a 34 year-old man who presented with chronic obscure gastrointestinal bleeding.

Integrin-linked kinase function is required for transforming growth factor beta-mediated epithelial to mesenchymal transition.

The role of integrin-linked kinase (ILK) in transforming growth factor beta (TGFbeta)-mediated epithelial to mesenchymal transition was investigated. A stable transfection of dominant-negative ILK results in the prevention of TGFbeta-mediated E-cadherin delocalization. TGFbeta-mediated phosphorylation of Akt at Ser-473 was inhibited by dominant-negative ILK and PI3K inhibitors, LY294002 and wortmannin. Treatment with TGFbeta stimulated induction of Akt and ILK kinase activity in HaCat control cells. This increased ILK activity by TGFbeta was lowered by PI3K inhibitor, LY294002. In addition, PI3K inhibitor, dominant-negative Akt, and dominant-negative ILK could not block TGFbeta-mediated C-terminal phosphorylation of Smad2. Taken together, these data suggest that PI3K-ILK-Akt pathway that is independent of the TGFbeta-induced Smad pathway is required for TGFbeta-mediated epithelial to mesenchymal transition.

Human hepatitis B virus-X protein alters mitochondrial function and physiology in human liver cells.

The hepatitis B virus-X protein (HBx) regulates fundamental aspects of mitochondrial physiology. We show that HBx down-regulates mitochondrial enzymes involved in electron transport in oxidative phosphorylation (complexes I, III, IV, and V) and sensitizes the mitochondrial membrane potential in a hepatoma cell line. HBx also increases the level of mitochondrial reactive oxygen species and lipid peroxide production. HBx does not activate apoptotic signaling, although it sensitizes hepatoma cells to apoptotic signaling, which is dependent on reactive oxygen species. Increased intrahepatic lipid peroxidation in HBx transgenic mice demonstrated that oxidative injury occurs as a direct result of HBx expression. Therefore, we conclude that mitochondrial dysfunction is a crucial pathophysiological factor in HBx-expressing hepatoma cells and provides an experimental rationale in the investigation of mitochondrial function in rapidly renewed tissues, as in hepatocellular carcinomas.