Insulin concentration is critical in culturing human neural stem cells and neurons.

Cell culture of human-derived neural stem cells (NSCs) is a useful tool that contributes to our understanding of human brain development and allows for the development of therapies for intractable human brain disorders. Human NSC (hNSC) cultures, however, are not commonly used, mainly because of difficulty with consistently maintaining the cells in a healthy state. In this study, we show that hNSC cultures, unlike NSCs of rodent origins, are extremely sensitive to insulin, an indispensable culture supplement, and that the previously reported difficulty in culturing hNSCs is likely because of a lack of understanding of this relationship. Like other neural cell cultures, insulin is required for hNSC growth, as withdrawal of insulin supplementation results in massive cell death and delayed cell growth. However, severe apoptotic cell death was also detected in insulin concentrations optimized to rodent NSC cultures. Thus, healthy hNSC cultures were only produced in a narrow range of relatively low insulin concentrations. Insulin-mediated cell death manifested not only in all human NSCs tested, regardless of origin, but also in differentiated human neurons. The underlying cell death mechanism at high insulin concentrations was similar to insulin resistance, where cells became less responsive to insulin, resulting in a reduction in the activation of the PI3K/Akt pathway critical to cell survival signaling.

Gene expression profile and enrichment pathways in different stages of bladder cancer.

Bladder cancer is a highly heterogeneous neoplasm. We examined the gene expression profile in 3 bladder cancer stages (Ta, T1, T2) using expression microarray analysis of 40 bladder tumors. Differentially expressed genes were found by the t-test, with <0.005 as the significance threshold. KEGG pathway-enrichment analysis was used to study the signaling pathways of the genes. We found 36 genes that could be used as molecular markers for predicting the transition from Ta-T1 to T1-T2. Among these, 11 overlapped between Ta-T1 and T1-T2 stages. Six genes were down-regulated at the Ta-T1 stage, but were up-regulated at the T1-T2 stage (ANXA5, ATP6V1B2, CTGF, GEM, IL13RA1, and LCP1); 5 genes were up-regulated at the Ta-T1 stage, but down-regulated at the T1-T2 stage (ACPP, GNL1, RIPK1, RAPGEF3, and ZER1). Another 25 genes changed relative expression levels at the T1-T2 stage. These genes (including COL1A1, COL1A2, FN1, ITGA5, LGALS1, SPP1, VIM, POSTN, and COL18A1) may be involved in bladder cancer progression by affecting extracellular matrix-receptor interaction and focal adhesion. The cytokine-cytokine receptor interaction, neuroactive ligand-receptor interaction, and calcium-signaling pathway were associated with bladder cancer progression at both the Ta-T1 and T1-T2 stages.

The role of liver transplantation for intrahepatic cholangiocarcinoma: a single-center experience.

BACKGROUND/AIM: Intrahepatic cholangiocarcinoma (ICC) is not a widely accepted indication for liver transplantation (LT). The present study describes our institutional experience with patients who underwent transplantation for ICC. METHODS: A retrospective analysis was performed on 11 consecutive patients with ICC who underwent LT between October 2003 and November 2008 at our institution. RESULTS: At a median patient follow-up interval of 10 months (2-56), the median survival time was 9 months (2.5-53). The perioperative mortality and the recurrence rate were 0 and 45.5%, respectively. Five patients are currently alive 10, 12, 41, 51 and 53 months after LT, respectively. One patient died 3 months after LT as a result of bile leak and toxic shock, and 5 patients died of tumor recurrences at 2.5, 8, 8, 9 and 10 months post-LT, respectively. The 1-, 2-, 3- and 4-year disease-free survival rates and overall survival rates of all the patients were 51.9, 51.9, 51.9 and 51.9%, and 50.5, 50.5, 50.5 and 50.5%, respectively. CONCLUSION: With better and strict patient selection, the prognosis of LT for ICC could be improved. ICC patients with lymph node involvement, vascular or bile duct invasion are contraindicated for LT.

Rapid and sensitive enzyme-linked immunosorbent assay and immunochromatographic assay for the detection of chlortetracycline residues in edible animal tissues.

Two rapid and sensitive enzyme-linked immunosorbent assays (ELISA) and an immunochromatographic assay (ICA) for the detection of chlortetracycline (CTC) residues in edible animal tissues were developed based on a monoclonal antibody (MAb) produced by using the chlortetracycline-bovine serum albumin (CTC-BSA) conjugate as the immunogen. A total of 50% inhibiting concentration (IC(50)) of the modified ELISA was 0.66 ng ml(-1) and the recoveries from spiked chicken muscle and liver were 78.8-92.2% and 80.3-90.2%, respectively. The corresponding coefficient variations (CVs) were 3.2-9.5% and 6.5-10.2%. The detection limit was 0.06 ng g(-1) in chicken muscle and 0.07 ng g(-1) in liver. However, the detection limit of ICA was 0.12 ng ml(-1), and the recoveries in negative samples spiked at concentrations of 10, 50 and 100 ng g(-1) ranged from 79.0% to 88.6% for muscle samples and from 75.2% to 87.0% for liver samples. The cut-off values for the test lines were 80 ng g(-1) and the analysis can be completed within 5-10 min. Comparisons with an HPLC method were performed by testing 200 swine muscle samples and chicken muscle samples from local markets, and an agreement rate of 99.5% was obtained between the three methods.

Single-center experience of therapeutic management of hepatic artery stenosis after orthotopic liver transplantation. Report of 20 cases.

BACKGROUND/AIMS: Hepatic artery stenosis (HAS) is a potentially life-threatening complication of liver transplantation because the associated mortality and morbidity rates are high. Surgical reconstruction was recommended as first choice of treatment and interventional radiologic techniques have been introduced recently. However, the mid- or long-term outcomes of HAS were unclear. The purpose of this study was to evaluate the efficacy of interventional therapy and clinical outcomes of HAS following liver transplantation. METHODS: A retrospective analysis was performed for 20 cases of HAS documented by angiography from October 2003 to August 2007 at the authors' institution. All patients underwent transluminal interventional therapy including percutaneous transluminal angioplasty and endovascular stent placement. The technical results, hepatic artery patency and clinical outcome were reviewed. RESULTS: All patients were treated with interventional management. Technical and immediate success was 100%. Of 8 patients with early HAS (within 1 month of transplantation), 1 underwent retransplantation due to deterioration of liver function. One died of acute liver failure waiting for retransplantation. Of 12 patients with late HAS (after 1 month of liver transplantation), 1 died of severe sepsis 38 days after transplantation. Five patients underwent late retransplantation due to ischemic-type biliary strictures or recurrent attacks of cholangitis. One of these patients died 11 days after retransplantation. The median follow-up of all 20 patients was 14.4 months after liver transplantation. The Kaplan-Meier curve of patency showed that cumulated primary patency of hepatic artery interventional treatment at 3, 6 and 12 months was 94, 87 and 79%, respectively. Two patients died of causes unrelated to HAS. Three patients developed recurrent HAS and were successfully treated with second interventional therapy. Eight patients (40%) developed ischemic-type biliary strictures and 7 underwent endoscopic treatment or percutaneous transhepatic cholangiodrainage. Graft function in 5 patients improved. The Kaplan-Meier curve of survival showed that the 1- and 2-year cumulated survival rates of early and late HAS were 87.5 and 43.8% and 81.5 and 61.1%, respectively. There was no significant difference in 1- and 2-year survival rates between early and late HAS (log-rank test, p = 0.928). CONCLUSION: Interventional therapy is an effective treatment for both early and late HAS with excellent short- and mid-term outcomes, while without irreversible graft dysfunction resulted from HAS. However, the patients have a high incidence of ischemic-type biliary lesions.

A single-center experience of retransplantation for liver transplant recipients with a failing graft.

With the accumulation of orthotopic liver transplantation (OLT) recipients, an increased number of patients with graft failure need retransplantation (re-OLT). This study was undertaken to examine our clinical experience of re-OLT for patients with poor graft function after primary transplantation at a single center. We analyzed retrospectively, the clinical data of 32 re-OLTs in 31 patients at our center from January 2004 to February 2007, including indications and causes of death, timing of retransplantation, and surgical techniques. The indications included bile leak (2 cases), biliary stricture (16 cases), recurrence of hepatocellular carcinoma (HCC) (5 cases), hepatic artery stenosis (4 cases), hepatic artery thrombosis (HAT) (2 cases), and hepatitis B recurrence (3 cases). The rate of re-OLT was 4.29%. All patients underwent modified piggyback liver transplantations with cadaveric allografts. No intraoperative mortality and acute rejection occurred. Overall, 17 of 31 patients (54.8%) died after re-OLT with survival times ranging from 2 weeks to 28 months. Another 14 patients were cured with survival times of 4 to 32 months. The perioperative mortality rate of patients who underwent re-OLT between 8 and 30 days after their initial transplantation was highest (66.7%). The most common cause of death after re-OLT was sepsis (47.1%), multiple-organ failure (17.6%), and recurrence of HCC (17.6%), whereas the majority of deaths posttransplantation were sepsis-related (54%) within 1 year. Re-OLT is the only therapeutic option for a failing liver graft. Proper indications and optimal operative time, advanced surgical procedures, reasonable individual immunosuppression regimens, and effective perioperative anti-infection treatments contribute to the improved survival of patients after re-OLT.

Purification and characterization of three different types of bile salt hydrolases from Bifidobacterium strains.

Bile salt hydrolases were purified to electrophoretic homogeneity from Bifidobacterium bifidum ATCC 11863, Bifidobacterium infantis KL412, Bifidobacterium longum ATCC 15708, Bifidobacterium longum KL507, and Bifidobacterium longum KL515. Three different types (A, B, and C) of bile salt hydrolase (BSH) were revealed during the purification study, exhibiting the type-specific characteristics in their electrophoretic migration and elution profiles from anion exchange and hydrophobic interaction chromatographic columns. The subunit molecular mass estimated by sodium dodecylsulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) was around 35 kDa, and the native molecular mass in all five Bifidobacterium strains was estimated to be between 130 and 150 kDa by gel filtration chromatography, indicating that all BSH enzymes have tetrameric structure. From the isoelectric focusing, an isoelectric point value of 4.45 was obtained with BSH (type B) from B. bifidum ATCC 11863 and the other BSH (types A and C) showed the similar pI values around 4.65. N-Terminal amino acid sequencing for the proteins of types A and C revealed that 6 out of 20 amino acid residues were different, and highly conserved residues were identified in both N-terminal sequences of types A and C. All BSH enzymes from five strains hydrolyzed six major human bile salts, and they showed a better deconjugation rate on glycine-conjugated bile salts than on taurine-conjugated forms.