Performance of the Assays for Hepatitis B Virus DNA using the μTASWako g1 in Comparison with the COBAS TaqMan Test

BACKGROUND

The quantification of hepatitis B virus (HBV) DNA is used to monitor antiviral treatment for HBV infection. Recently, an HBV-DNA quantification reagent and assay protocol have been developed for the µTASWako g1 (Fujifilm Wako Pure Chemical Corporation, Osaka, Japan), a fully automated genetic analyzer that uses PCR-capillary electrophoresis. We evaluated the performance of the newly developed µTASWako HBV-DNA assay using standard and clinical samples.

METHODS

The performance of µTASWako HBV-DNA was evaluated using 3rd World Health Organization International Standard for HBV. Thereafter, we evaluated the correlation between the serum HBV DNA concentrations obtained using the µTASWako HBV-DNA and the Roche Cobas AmpliPrep/COBAS TaqMan HBV test, version 2.0 (CAP/CTM HBV test v.2.0) using 190 serum samples from possible HBV carriers.

RESULTS

The limit of detection of the µTASWako HBV-DNA was 7.1 IU/mL and that of the CAP/CTM HBV test v.2.0 was 14.6 IU/mL. Seventy-six of the 190 samples yielded values between 1.3 - 7.8 log IU/mL from both assays. The correlation between the results of the assays for these samples was good, with a Deming regression equation of y = 0.929x + 0.041, 95% confidence intervals (CI) for the slope and intercept of 0.892 - 1.12 and -0.474 - 0.110, respectively, and a correlation coefficient r = 0.924. In the low concentration range of 1.3 - 4.0 log IU/mL (n = 64), the Deming regression equation was y = 0.893x + 0.126, and the 95% CIs for the slope and intercept were 0.915 - 1.342 and -0.930 - 0.025, respectively, and r = 0.809. There was also a close correlation for HBV DNA genotype C (n = 41), with a Deming regression equation of y = 0.975x - 0.048, 95% CIs of the slope and intercept of 0.872 - 1.183 and -0.591 - 0.188, respectively, and r = 0.950. The correlations of the four HBV DNA level categories (not detected, < LLOQ (< 1.3 log IU/mL), 1.3 - 3.2 log IU/mL, and ≥ 3.3 log IU/mL) between the two assays for the 190 samples was also compared, and the overall concordance rate was 81.6% (155/190), with a κ statistic of 0.73 (standard error, 0.040; 95% CI, 0.647 - 0.803).

CONCLUSIONS

The µTASWako HBV-DNA has a performance comparable with that of the CAP/CTM HBV test, v.2.0. Thus, µTASWako HBV-DNA is useful for the monitoring of HBV infection.

First report of New Delhi metallo-β-lactamase-1-producing Acinetobacter soli in Japan

New Delhi metallo-β-lactamase (NDM)-producing gram-negative rods, including Acinetobacter species, are a global problem but have rarely been isolated in Japan. To our knowledge, this is the first study to isolate an NDM-1-producing Acinetobacter soli strain, KUH106, in Japan. We analyzed this strain using next-generation sequencing to examine the plasmid carrying NDM-1. This plasmid, named pKUH106_NDM1, is 41,135 bp in length and contains genetic contexts with the structure ISAba14-aph(3')-VI-ISAba125-blaNDM-1ble-MBL. Comparative analysis of the plasmid revealed that it resembled the plasmids of Acinetobacter detected in various countries, such as the A. soli isolate from Taiwan and the Acinetobacter baumannii isolate from a healthcare facility in Osaka Prefecture, Japan. These results suggest that blaNDM-1 may spread via this plasmid in Acinetobacter species. This phenomenon needs to be confirmed through the genetic analysis of A. baumannii and other carbapenem-resistant Acinetobacter species. In particular, blaNDM-1 and other resistance genes must be investigated, and the spread of these genes in the community must be cautioned.

Antimicrobial Susceptibility to 27 Drugs and the Molecular Mechanisms of Macrolide, Tetracycline, and Quinolone Resistance in Gemella sp

Gemella is a catalase-negative, facultative anaerobic, Gram-positive coccus that is commensal in humans but can become opportunistic and cause severe infectious diseases, such as infective endocarditis. Few studies have tested the antimicrobial susceptibility of Gemella. We tested its antimicrobial susceptibility to 27 drugs and defined the resistant genes using PCR in 58 Gemella strains, including 52 clinical isolates and six type strains. The type strains and clinical isolates included 22 G. morbillorum, 18 G. haemolysans (GH) group (genetically indistinguishable from G. haemolysans and G. parahaemolysans), 13 G. taiwanensis, three G. sanguinis, and two G. bergeri. No strain was resistant to beta-lactams and vancomycin. In total, 6/22 (27.3%) G. morbillorum strains were erythromycin- and clindamycin-resistant ermB-positive, whereas 4/18 (22.2%) in the GH group, 7/13 (53.8%) G. taiwanensis, and 1/3 (33.3%) of the G. sanguinis strains were erythromycin-non-susceptible mefE- or mefA-positive and clindamycin-susceptible. The MIC90 of minocycline and the ratios of tetM-positive strains varied across the different species-G. morbillorum: 2 µg/mL and 27.3% (6/22); GH group: 8 µg/mL and 27.8% (5/18); G. taiwanensis: 8 µg/mL and 46.2% (6/13), respectively. Levofloxacin resistance was significantly higher in G. taiwanensis (9/13 69.2%) than in G. morbillorum (2/22 9.1%). Levofloxacin resistance was associated with a substitution at serine 83 for leucine, phenylalanine, or tyrosine in GyrA. The mechanisms of resistance to erythromycin and clindamycin differed across Gemella species. In addition, the rate of susceptibility to levofloxacin differed across Gemella sp., and the quinolone resistance mechanism was caused by mutations in GyrA alone.

Evaluation of the Analytical Performance of the Fully Automated Gene Analyzer µTASWako g1 for the Detection of SARS-CoV-2

BACKGROUND

The worldwide spread of coronavirus disease 2019 (COVID-19) has led to an urgent need for nucleic acid amplification test (NAAT) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Because NAAT has many manual processes, results may vary depending on the operator. Therefore, it has been required to develop a fully automated testing device and reagent that detects genetic material from SARS-CoV-2. The µTASWako g1 system (FUJIFILM Wako Pure Chemical Corporation, Osaka, Japan), a genetic analyzer, provides results in 75 minutes by performing a fully automated PCR process.

METHODS

We evaluated the analytical and clinical performance of the µTASWako g1 system for the detection of SARS-CoV-2 RNA.

RESULTS

The µTASWako g1 system had the limit of detection at 2,000 copies/mL using a known concentration of RNA. In clinical samples, the µTASWako g1 system had a sensitivity of 88.0% and 100% specificity compared to conventional RT-PCR. The µTAS Wako g1 system could detect three variants of concern carrying spike mutations including N501Y, E484K, and L452R.

CONCLUSIONS

As the assay on the µTASWako g1 system is highly accurate for the detection of SARS-CoV-2 regardless of the experience of operator, it can be widely applicable in clinical laboratories.

Study on the Mechanism of False Low Measurement of IgG-Binding (Affinity) IgM Type M Protein by Turbidimetric Immunoassay

BACKGROUND

The purpose of this study was to investigate the immunological and physical characteristics of IgM-λ type M-protein from patients who were measured low in the turbidimetric immunoassay (TIA) IgM assay without error codes for high concentration to determine the cause of the false low levels and to clarify the mechanism of their occurrence.

METHODS

Materials were IgM patient samples and 8 serum samples from other IgM M-protein patients as controls. Patient samples were assayed by the TIA method, in which five manufacturers and six models (two reagent manufacturers) share the principle, and the BN ProSpec method (nephelometric method), which has a different principle. Dilution linearity tests, IgG addition experiments, isoelectric point electrophoresis, and hydrophobic chromatography were performed on patients and subjects. In addition, the binding capacity of γ-globulin by BIACORE was also examined.

RESULTS

The reaction curve of the patient IgM curved downward when the concentration of IgM exceeded 20 g/L, and no error code was obtained. In the measurement by the TIA method of five manufacturers and six models, patient IgM was measured at a false low level with no error code obtained in undiluted dilution by any of the instruments and reagents, but could be measured without any problem by the nephelometric method. In addition, in the patient IgG addition experiment, only patient IgM showed a false low level under high IgG concentration. Furthermore, the binding capacity of patient IgM to γ-globulin (IgG) by BIACORE was significantly higher than that of the control IgM-type M protein.

CONCLUSIONS

Patient IgM has an affinity (binding capacity) for IgG and forms an IgM-IgG complex under conditions of high IgG concentration. It was speculated that this complex inhibited the reaction with the anti-IgM antibody and the absorbance of the second reaction did not increase, suggesting a false low.

Oltipraz ameliorates the progression of steatohepatitis in Nrf2-null mice fed a high-fat diet

Oltipraz, a synthetic dithiolethione, has chemopreventive effect through nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Nrf2 is known to be involved in the development of experimental steatohepatitis in rodents. In this study, to evaluate the effect of oltipraz on lipid and bile acid metabolism, wild-type and Nrf2-null mice were fed the standard diet (containing 4% soybean oil) with or without oltipraz. Based on these results, we examined the effect of oltipraz on the experimental steatohepatitis in high-fat diet (containing 4% soybean oil and 20% lard) fed Nrf2-null mice. Oltipraz induced hepatic mRNA expression of peroxisome proliferator-activated receptor α, carnitine palmityl transferase 1, and bile salt export pump by Nrf2 independent mechanisms. In Nrf2-null mice fed a high-fat diet for 12 weeks, moderate to severe inflammation and fibrosis were observed. Oral administration of oltipraz suppressed the degree of inflammation and fibrosis in Nrf2-null mouse liver fed a high-fat diet. These histopathological findings approximately corresponded to the data of mRNA expression of tumor necrosis factor α, monocyte chemoattractant protein-1, Timp-1, and collagen type 1α1. These results indicated that oltipraz administration ameliorated liver injury by Nrf2 independent manner in a model of steatohepatitis generated by Nrf2-null mice with high-fat diet.

Regulation of the expression of cholesterol transporters by lipid-lowering drugs ezetimibe and pemafibrate in rat liver and intestine

Ezetimibe and pemafibrate are lipid-lowering drugs and promote reverse cholesterol transport. However, it is unknown whether cholesterol is mainly excreted by hepatobiliary excretion or by non-biliary transintestinal cholesterol efflux (TICE). We evaluated the effects of ezetimibe and pemafibrate on hepatic and intestinal cholesterol transporter regulation in Sham-operated rats, and examined the effects of these drugs on TICE in bile duct-ligated rats. Seven-week-old male Sprague-Dawley rats were treated as follows for two weeks: 1) Sham, Sham operation; 2) BDL, bile duct ligation; 3) E-Sham, Sham + ezetimibe; 4) E-BDL, BDL + ezetimibe; 5) P-Sham, Sham + pemafibrate; and 6) P-BDL, BDL + pemafibrate. Blood, liver, jejunum, and feces were collected 72 h post-surgery. Hepatic cholesterol levels were decreased in P-Sham and E-Sham, and were lower in E-BDL and P-BDL than in BDL. Fecal cholesterol levels increased in E-Sham and P-Sham compared with Sham, and were higher in E-BDL and P-BDL than in BDL. In liver, Abcg5 mRNA showed induction in E-Sham, Abcg5 and Abca1 mRNA were induced in P-Sham, Abcg5 mRNA was reduced in E-BDL, and Abca1 mRNA was increased in P-BDL. In jejunum, Abcg5 mRNA was induced in E-Sham. Abcg8 mRNA was induced in E-Sham and P-Sham. NPC1L1 mRNA showed reduced expression in P-Sham and P-BDL. SR-B1 mRNA was reduced in P-Sham, and the expression decreased in P-BDL. LDL receptor mRNA was induced in BDL and P-BDL. Ezetimibe and pemafibrate may promote TICE by increasing Abcg5/g8, while pemafibrate may inhibit intestinal cholesterol absorption by decreasing SR-B1 and NPC1L1.

Performance evaluation of leukocyte differential on the hematology analyzer Celltac G compared with two hematology analyzers, reference flow cytometry method, and two manual methods

BACKGROUND

The automated hematology analyzer Celltac G (Nihon Kohden) was designed to improve leukocyte differential performance. Comparison with analyzers using different leukocyte detection principles and differential leukocyte count on wedge film (Wedge-Diff) shows its clinical utility, and comparison with immunophenotypic leukocyte differential reference method (FCM-Ref) shows its accuracy performance.

METHODS

For method comparison, 598 clinical samples and 46 healthy volunteer samples were selected. The two comparative hematology analyzers (CAAs) used were XN-9000 (Sysmex) and CELL-DYN Sapphire (Abbott). The FCM-Ref provided by the Japanese Society for Laboratory Hematology was selected, and a flow cytometer Navios (Beckman-Coulter) was used. In manual differential, two kinds of automated slide makers were used: SP-10 (Sysmex) for wedge technique and SPINNER-2000 (Lion-Power) for spinner technique. The spinner technique avoids the issue of Wedge-Diff smudge cells by removing the risk of breaking cells and non-uniformity of blood cell distribution on films (Spinner-Diff).

RESULTS

The Celltac G showed sufficient comparability (r = 0.67-1.00) with the CAAs for each leukocyte differential counting value at 0.00-40.87(10⁹ /L), and sufficient comparability (r = 0.73-0.97) with FCM-Ref for each leukocyte differential percentage at 0.4-78.5. The identification ratio of the FCM-Ref in CD45-positive cells was 99.7% (99.4% to 99.8%). Differences were found between FCM-Ref/Celltac G/XN-9000/Spinner-Diff and Wedge-Diff for monocytes and neutrophils. The appearance ratio of smudge cells on wedge and spinner film was 12.5% and 0.5%.

CONCLUSION

The Celltac G hematology analyzer's leukocyte differential showed adequate accuracy compared with the CAAs, FCM-Ref, and two manual methods and was considered suitable for clinical use.

Platelet count evaluation compared with the immunoplatelet reference method and performance evaluation of the hematology analyzer Celltac G

INTRODUCTION

The hematology analyzer, Celltac G (Nihon Kohden), designed to improve platelet count (Plt) accuracy, is equipped with new sheath flow control technology. Clinical evaluation of the Celltac G was assessed by comparability with XN-9000 (Sysmex Corporation) and CELL-DYN Sapphire (Abbott Diagnostics). The accuracy of all three analyzers, which use different measuring principles, was compared with the immunoplatelet reference method (FCM-Ref).

METHODS

Repeatability and within-laboratory imprecision were assessed using 10 clinical fresh whole blood samples and three control materials with differing levels. Carryover was evaluated using 6 clinical fresh whole blood samples. For method comparison between the three analyzers, 388 samples were used. Plt accuracy among the three analyzers was evaluated using 54 blood samples, including 42 samples with a platelet count less than 50x10⁹ /L. The International Council for Standardization in Haematology method for Plt was used as the FCM-Ref.

RESULTS

The Celltac G showed sufficient performance with regard to imprecision, carryover, and comparability. The Analytical Measurement Interval (AMI) and linearity for all parameters of Plt were validated within 4.6 to 809.1 (×10⁹ /L). All hematology analyzers showed some disagreement in Plt when compared with the immunoplatelet reference method.

CONCLUSION

The Celltac G hematology analyzer is suitable for clinical use. Platelet count evaluation of the three analyzers suggests the need to determine a reportable measurement interval (RMI) in the clinical laboratory for adequate reporting of a Plt from multiple different values.

Glycosylated Bence Jones Protein with Poor Thermal Reactivity in Heat Coagulation Tests

BACKGROUND

We experienced a patient with multiple myeloma whose urine contained a considerable amount of Bence Jones protein (BJP), which demonstrated poor thermal reactivity in heat coagulation test. The mechanism for this phenomenon was assessed.

METHODS

Immunoelectrophoretic analyses reveal that a band corresponding to BJP in the urine had 2,600 Dalton by reduction after glycosidase treatment, but not after sialidase treatment. In addition, the glycosidase-treated urine tested positive in heat coagulation test.

CONCLUSIONS

Glycosylation of the immunoglobulin light chain, which has rarely been seen, is the cause of the unexpected behavior of this patent's BJP in heat coagulation tests.

Epidemiological and molecular characterization of invasive Streptococcus pneumoniae isolated following introduction of 7-valent conjugate vaccine in Kinki region, Japan, 2008-2013

Streptococcus pneumoniae is one of the most common bacteria causing community-acquired pneumonia and meningitis. The use of 7-valent pneumococcal conjugate vaccine (PCV7) has reduced the incidence of pneumococcal disease while changing pneumococcal population through herd immunity and non-vaccine pneumococci replacement. This study investigated molecular epidemiologic characteristics of pneumococcal strains in the Kinki region of Japan from 2008 to 2013. A total of 159 invasive pneumococcal isolates were characterized by serotyping, antibiotic susceptibility testing, PCR analysis of penicillin-binding protein genes, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE). In adult populations, pediatric PCV7 introduction decreased isolates expressing PCV7 serotypes via herd immunity and increased isolates expressing non-PCV7 serotypes. The rate of penicillin resistance and isolates with alterations in all three pbp genes was higher in PCV7 type isolates than in non-PCV7 type isolates. In MLST analysis, all of serotype 19F isolates were of the same sequence type, ST236, which is the antimicrobial-resistant clone Taiwan^19F-14, and the majority of serotypes 23F and 19A isolates were of ST1437 and ST3111 respectively, which are the predominant clones of antimicrobial-resistant pneumococci in Japan. In PFGE profiles, serotype 6B-ST2224, serotype 19F-ST236, serotype 19A-ST3111, and serotype 23F-ST1437 formed six separate clusters composed of genetically identical strains, and genetically identical serotype 22F-ST433 formed two different clusters between the pre- and post-PCV7 period. The results of molecular analysis suggest the spread and persistence of these identical antimicrobial resistant clones in the Kinki region and genetic changes of epidemic clone serotype 22F-ST433 before and after pediatric PCV7 introduction.

Gender-divergent expression of lipid and bile acid metabolism related genes in adult mice offspring of dams fed a high-fat diet

Maternal high-fat diet (HFD) consumption during pregnancy and lactation affects metabolic outcomes and lipid metabolism of offspring in later life in a gender-specific manner. However, it is not known whether maternal HFD alters bile acid metabolism in adult mice offspring. The purpose of this study was to elucidate the relationship between maternal HFDinduced metabolic diseases and bile acid metabolism in male and female adult mice offspring. Female mice were fed either standard chow (C) or HFD (H) for 10 weeks pre-pregnancy until lactation. After weaning, offspring were fed a chow diet until 11 weeks of age, then challenged with either C or H diet for 4 weeks, and divided into eight groups in accordance with mother's and offspring's diets: male(M) CC, MHC, MCH, MHH, female(F) CC, FHC, FCH, and FHH. MHH showed greater weight gain compared to FHH. Liver weight was higher in MHH than in FHH. Serum total cholesterol levels were higher in MHH than in MHC, and tended to be higher in MHH than in FHH. Serum glucose levels were higher in MHH than in MHC. Hepatic triglyceride levels were higher in MHH than in MHC. Hepatic mRNA expression of bile acid uptake transporters Oatp1a1 and Oatp1b2 was increased in MHH, compared to MCH. Hepatic mRNA expression of HMGCoAR, Cyp7a1, Sult2a1, and Oatp1a4 was increased in FHH, compared to FCH. In conclusion, maternal HFD consumption may promote bile acid synthesis, sulfation and excretion in female offspring fed a HFD, which may confer resistance to HFDinduced metabolic phenotypes.

Laboratory surveillance of antimicrobial resistance and multidrug resistance among Streptococcus pneumoniae isolated in the Kinki region of Japan, 2001-2015

The 7-valent pneumococcal conjugate vaccine (PCV7) was introduced among children in Japan in 2010. There are no long-term multicenter surveillance studies of antimicrobial resistance in S. pneumoniae before and after the introduction of PCV7. Therefore, we examined chronological trends in antimicrobial resistance among 4534 strains of S. pneumoniae isolated from both children and adults in the Kinki region of Japan during 2001-2015. High-level penicillin and third-generation cephalosporin resistance in S. pneumoniae increased among both children and adults during the period before the introduction of PCV7 (2001-2010). Besides penicillin and cephalosporin, pneumococcal carbapenem and macrolide resistance increased among children. The rate of resistance to these antibiotics was higher among children than among adults. The introduction of PCV7 decreased the rate of non-susceptibility to β-lactam antibiotics and the rate of multidrug resistant S. pneumoniae among children, but not among adults.

Evaluation of menstrual cycle-related changes in 85 clinical laboratory analytes

OBJECTIVE

The menstrual cycle-related changes in clinical laboratory values were analysed by use of data obtained in the Asian multicentre study aimed at derivation of common reference intervals for 85 major clinical laboratory tests.

METHODS

Among 1876 healthy female volunteers, 893 had regular menstruation. They were classified into five groups according to dates between sample collection and the start of the last menstrual cycle: early follicular phase (1-6 days), late follicular phase (7-12 days), ovulatory phase (13-16 days), early luteal phase (17-22 days), and late luteal phase (23-31 days). Multiple linear regression analysis was performed to evaluate the menstrual cycle-related changes in test results. The magnitude was expressed as a standard deviation ratio of between-phase standard deviation to between-individual standard deviation based on nested ANOVA.

RESULTS

Aside from obvious changes for four sex hormones (oestradiol, progesterone, follicle-stimulating hormone, and luteinizing hormone), we observed statistically significant menstrual cycle-related changes in the following tests (standard deviation ratio >0.15): Na, Cl, creatine kinase, C-reactive protein, serum amyloid A, carbohydrate antigen 125, and parathyroid hormone were higher during the early follicular phase, while insulin, total cholesterol, and white blood cell were higher during the luteal phase. Significant associations of those test items with the four sex hormones were revealed.

CONCLUSIONS

The menstrual cycle-related changes in laboratory test results were revealed in some commonly tested items other than sex hormones. The findings are of interest in understanding female physiology in relation to hormonal changes, but the magnitude of changes is rather small and not very relevant in interpreting test results.

Role of Nrf2 in the alteration of cholesterol and bile acid metabolism-related gene expression by dietary cholesterol in high fat-fed mice

Nuclear factor-E2-related factor 2 (Nrf2) is a regulator of lipid metabolism as well as various cytoprotective enzymes and may be involved in the pathogenesis of non-alcoholic fatty liver disease. Although, bile acids affect lipid metabolism, the role of Nrf2 in bile acid metabolism remains unclear. In this study, it was tested how Nrf2 modulates lipid and bile acid homeostasis in liver in response to changes of cholesterol absorption under high-fat diet using Nrf2-null mice. Eight-week-old male wild-type and Nrf2-null mice (n = 6/group) were divided into three groups fed the following diets: 1) control diet containing 4% soybean oil and 16% lard, 2) control diet plus ezetimibe, 3) control diet plus cholesterol. Blood and livers were removed after 4 weeks feeding. High cholesterol diet increased hepatic expression of liver X receptor α target genes related to fatty acid metabolism (FAS, ACC1, SREBP-1c, SCD-1c and CD36), cholesterol transport (Abcg5/abcg8) and bile acid synthesis (Cyp7a1) in wild type mice. However, these genes were not induced in Nrf2-null mice. These findings suggest that Nrf2 has a relation to liver X receptor α and controls the regulation of gene expressions related to lipid and bile acid metabolism.

[Relationship between serum hCG and urinary hCG in cases of pregnancy, abortion, and hydatidiform mole]

Human chorionic gonadotropin (hCG) is generally quantified in serum, but spot urine samples are also used to assess hCG levels in Japan. The purpose of the present study was to elucidate whether urinary hCG can be used clinically as a substitute for serum hCG. A total of 189 samples of serum and spot urine were collected from patients, including cases of normal pregnancy (NP) -13, abortion (AB) -21, extrauterine pregnancy (EP) 25, and hydatidiform mole (MOL) -7, during medical treatment and comparisons were made concerning serum and urinary hCG levels. The histogram of relative urinary/serum hCG(U-hCG.act/S-hCG) of the samples showed a wide distribution of values, but tended to converge to a narrow distribution by creatinine correction (U-hCG.cor/S-hCG). U-hCG.cor/S-hCG of the AB, EP, and MOL groups decreased 1 day to 14 days or was no earlier than 15 days postoperatively compared to preoperatively. The alteration of serum Intact/Total tended to be similar to that of U-hCG.cor/S-hCG in clinical course. The presented case indicated that U-hCG.act/S-hCG did not correspond to serum hCG levels. Because urinary hCG levels are inconsistent depending on whether spot urine is concentrated or diluted, the levels of hCG in spot urine do not always correlate with serum levels of hCG. Therefore, the data of urinary hCG should be interpreted after creatinine correction. Overall, it is recommended to determine serum hCG levels rather than creatinine corrected urinary hCG levels, considering that the relative urinary/serum hCG was not constant postoperatively.

Ezetimibe increases hepatic iron levels in mice fed a high-fat diet

Accumulating evidence suggests that ezetimibe may be a promising agent for treatment of nonalcoholic fatty liver disease and steatohepatitis (NAFLD/NASH). Phlebotomy and dietary iron restriction reduce serum transaminase in NAFLD/NASH patients. Recent studies have shown that a mutual effect exists between lipid metabolism and iron metabolism. Accordingly, we examined the effect of ezetimibe on iron metabolism in mice fed a high-fat diet with or without iron. We fed C57BL/6 mice the following diets for 12 weeks. Experiment 1 comprised [1] a control diet (C), [2] C plus ezetimibe (0.3 mg/day; 4 weeks) (CE), [3] a high-fat diet (H), and [4] H plus ezetimibe (HE). Experiment 2 comprised [1] C containing carbonyl iron (average; 22.4 mg/day; 6 weeks) (CI), [2] CI plus ezetimibe (CIE), [3] H containing carbonyl iron (HI), and [4] HI plus ezetimibe (HIE). Blood, livers, and duodenum were removed after 12 weeks. In experiment 1, the hepatic iron levels were higher in HE than H, whereas there was no difference between C and CE. Hepatic mRNA expression of transferrin receptor 1 and 2, ferritins, and hepcidin were increased more in CE than C, and more in HE than H. In the duodenum, divalent metal transporter 1, ferritin H, and hephaestin mRNA levels were increased in CE compared with C. In experiment 2, hepatic iron concentrations were higher in HIE than HI. Hepatic mRNA expression of ferritin L and hepcidin were increased in HIE compared with HI. In duodenum, ferritin L mRNA was increased in HIE compared with CIE. Ezetimibe induced hepatic iron uptake transporter expression in mice fed a high-fat diet, causing increased hepatic iron concentrations.

Dysregulated expression of fatty acid oxidation enzymes and iron-regulatory genes in livers of Nrf2-null mice

BACKGROUND AND AIM

Hepatic excessive iron may play a role in the pathogenesis of non-alcoholic steatohepatitis (NASH). Nrf2 is a master regulator of antioxidative responses. However, the role of Nrf2 in lipid and iron homeostasis remains unclear. Accordingly, it was examined how Nrf2 regulates lipid-related and iron-regulatory genes after feeding a high-fat diet (HFD) with iron.

METHODS

Wild-type and Nrf2-null mice were fed the following diets: (i) control diet (4% soybean oil) for 12 weeks, (ii) control diet for 8 weeks followed by control diet containing 0.5% carbonyl iron for 4 weeks, (iii) HFD (4% soybean oil and 16% lard) for 12 weeks, (iv) HFD for 8 weeks followed by HFD containing 0.5% carbonyl iron for 4 weeks. Blood and livers were removed after 12 weeks.

RESULTS

Nrf2-null control mice exhibited a tendency towards higher hepatic triglycerides compared to wild-type control mice. Hepatic malondialdehyde was higher and hepatic iron levels tended to be higher in Nrf2-null mice than wild-type counterparts while on a HFD. The HFD with iron synergistically induced mRNA expression of Pparα targets, including Acox and Cpt1 in wild-type mice, yet the induction was diminished in Nrf2-null mice. Hepatic hepcidin and ferroportin 1 mRNA expression were increased in wild-type mice after feeding a HFD with iron, but were unchanged in any group of Nrf2-null mice.

CONCLUSIONS

Nrf2 deletion dysregulates hepatic mRNA expression of β-oxidation enzymes and iron-related genes, possibly causing a trend for increased hepatic triglyceride and iron concentrations. Nrf2 may have roles in the progression of NASH.

[Divergence between measured values of total IgG and subclass IgGs (sum of IgG1-IgG4) in IgG4-related disease]

In systemic IgG4-related disease, an elevation of the serum IgG4 level(IgG4: 135 mg/dl or higher) and IgG4-positive plasma cell infiltration occurs. Since the total IgG and sum of subclasses, IgG1 through IgG4, were markedly different in a patient suspected of having Mikuliez's disease, we investigated the relationship between total IgG and sum of IgG subclasses. The subjects were healthy individuals, and low IgG4, high IgG4, hyper-gamma globulinemia and hypo-y globulinemia groups. Total IgG was measured using 'N-assay TIA IgG-SH' (Nittobo) and Hitachi 7700, and IgG subclasses were measured using BS-NIA reagent (Binding Site) and BN II (Siemens). Designation of total IgG and the sum of IgG subclasses was established in the healthy control subjects. However the total IgG level and sum of IgG1-4 levels were different when the balance among the IgG subclasses was lost. In case such as :1) the IgG4 level was high and 2) IgG1-type M protein was present. These results indicate that the reevaluation of measured data is necessary when the IgG4 concentration is high and the difference between total IgG concentration and the sum of IgG subclasses is large.

Dietary fish oil regulates gene expression of cholesterol and bile acid transporters in mice

AIM

  Fish oil rich in n-3 polyunsaturated fatty acids is known to affect hepatic lipid metabolism. Several studies have demonstrated that fish oil may affect the bile acid metabolism as well as lipid metabolism, whereas only scarce data are available. The aim of this study was to investigate the effect of fish oil on the gene expression of the transporters and enzymes related to bile acid as well as lipid metabolism in the liver and small intestine.

METHODS

  Seven-week old male C57BL/6 mice were fed diets enriched in 10% soybean oil or 10% fish oil for 4 weeks. After 4 weeks, blood, liver and small intestine were obtained.

RESULTS

  Hepatic mRNA expression of lipids (Abcg5/8, multidrug resistance gene product 2) and bile acids transporters (bile salt export pump, multidrug resistance associated protein 2 and 3, organic solute transporter α) was induced in fish oil-fed mice. Hepatic Cyp8b1, Cyp27a1 and bile acid CoA : amino acid N-acyltransferase were increased in fish oil-fed mice compared with soybean-oil fed mice. Besides, intestinal cholesterol (Abcg5/8) and bile acid transporters (multidrug resistance associated protein 2 and organic solute transporter α) were induced in fish oil-fed mice.

CONCLUSION

  Fish oil induced the expression of cholesterol and bile acid transporters not only in liver but in intestine. The upregulation of Abcg5/g8 by fish oil is caused by an increase in cellular 27-HOC through Cyp27a1 induction. The hepatic induction of bile acid synthesis through Cyp27a1 may upregulate expression of bile acid transporters in both organs.

[The values of multi-laboratories serum values evaluation]

The members of 23 laboratories, ten clinical laboratory centers and thirteen hospital laboratories in the Kinki District participated in share their clinical laboratory data. In this joint work, we cross-checked twenty-seven serum values, and all data from the 23 laboratories well accorded; however, several values, such as urea nitrogen, calcium, and albumin needed to be standardized to share the laboratory data.

[Efforts of medical technologists for cancer patients--a questionnaire survey following a lecture meeting: "cancer treatment and clinical examinations" for cancer patients and their families]

As interprofessional work in cancer treatment becomes increasingly important, medical technologists are required to play active roles as part of the team. The cancer center of our hospital organized a lecture meeting, "The 6th Lecture Meeting: Living Together," for cancer patients and their families, and a medical technologist presented a lecture entitled: "Cancer treatment and clinical examinations." According to the results of a questionnaire survey conducted following the meeting, most participants were able to understand the lecture and were satisfied with it. Based on the opinions expressed by meeting participants and the questionnaire results, medical technologists initiate the following services and activities: 1. They explain the results of white blood cell and neutrophil counts of patients on chemotherapy and/or radiation therapy; and 2. provide medical examinations and consultation at outpatient chemotherapy centers. We believe that these efforts will help improve cancer treatment and further contribute to interprofessional health care.

Influenza A virus abrogates IFN-gamma response in respiratory epithelial cells by disruption of the Jak/Stat pathway

The innate immunity to viral infections induces a potent antiviral response mediated by interferons (IFN). Although IFN-gamma is detected during the acute stages of illness in the upper respiratory tract secretions and in the serum of influenza A virus-infected individuals, control of influenza A virus is not dependent upon IFN-gamma as evidenced by studies using anti-IFN-gamma Ab and IFN-gamma(-/-) mice. Thus, we hypothesized that IFN-gamma is not critical in host survival because influenza A virus has mechanisms to evade the antiviral activity of IFN-gamma. To test this, A549 cells, an epithelial cell line derived from lung adenocarcinoma, were infected with influenza virus strain A/Aichi/2/68 (H3N2) (Aichi) and/or stimulated with IFN-gamma to detect IFN-gamma-stimulated MHC class II expression. Influenza A virus infection inhibited IFN-gamma-induced up-regulation of HLA-DRalpha mRNA and the IFN-gamma induction of class II transactivator (CIITA), an obligate mediator of MHC class II expression. Nuclear translocation of Stat1alpha upon IFN-gamma stimulation was significantly inhibited in influenza A virus-infected cells and this was associated with a decrease in Tyr701 and Ser727 phosphorylation of Stat1alpha. Thus, influenza A virus subverts antiviral host defense mediated by IFN-gamma through effects on the intracellular signaling pathways.

Effect of cholesterol, cholic acid and cholestyramine administration on the intestinal mRNA expressions related to cholesterol and bile acid metabolism in the rat

BACKGROUND AND AIM

To evaluate the importance of cholesterol and bile acid concentrations in the intestinal lumen to cholesterol homeostasis, we investigated the effect of cholesterol-, bile salt- or cholestyramine-administration on the regulation of intestinal mRNA related to cholesterol and bile acid metabolism.

METHODS

Male Wistar rats fed on standard laboratory chow (AIN-93) were allocated into four experimental groups: (i) control group; (ii) cholesterol group (CH), which was fed cholesterol in diet (2% [w/w]) for 14 days; (iii) cholic acid (CA) group, which was fed CA in diet (1% [w/w]) for 14 days; (iv) cholestyramine (CT) group, which was fed CT in diet (5% [w/w]) for 14 days. Blood, liver and small intestine were obtained after 14 days. Serum lipids and bile acids were measured by colorimetric assays, and hepatic and intestinal mRNA relating to lipid and bile acid metabolism was studied by reverse transcription-polymerase chain reaction.

RESULTS

Intestinal ABCG8, liver X receptor alpha, small heterodimer partner (SHP) and sterol regulatory element binding protein 1c (SREBP-1c) mRNA expressions were markedly increased in the CH group. Intestinal multidrug resistance associated protein (MRP) 2 and MRP3 mRNA expressions were markedly increased in the CA group. In the CT group intestinal MRP2, ABCG5, ABCG8, SHP and SREBP-1c mRNA expressions were markedly decreased.

CONCLUSION

The bile acid availability in the intestinal lumen alters the expression of various intestinal mRNA relating to not only bile acid metabolism, but also lipid metabolism. Though the mechanism of the intestinal SHP elevation is unclear, cholesterol feeding may affect the intestinal bile acid metabolism via intestinal SHP expression.

Effects of osthol on blood pressure and lipid metabolism in stroke-prone spontaneously hypertensive rats

Osthol, a coumarin compound, was isolated from the dried fruits of Cnidium monnieri (Umbelliferae) and the effect of dietary osthol on hypertension and lipid metabolism was examined in stroke-prone spontaneously hypertensive rats (SHRSP). Six-week-old male SHRSP were fed the experimental diet containing 0.05% osthol by weight for 4 weeks with free access to the diet and water. Elevation of systolic blood pressure was significantly suppressed on and after 3 weeks. In addition, significant decreases in cholesterol and triglyceride contents in the liver were recognized without any significant changes in serum lipids profiles. A comparative study on hepatic mRNA expression indicated that osthol induced a significant increase in 3-hydroxy-3-methylglutaryl coenzymeA (HMG-CoA) reductase mRNA expression, which may lead to decrease in hepatic cholesterol pool through inhibition of the enzyme activity. Moreover, osthol induced a significant increase in acyl-CoA oxidase mRNA expression associated with an increase in carnitine palmitoyl transferase 1a mRNA expression, which suggests the acceleration of beta-oxidation of hepatic fatty acids. This may be responsible, at least in part, for the reduction of hepatic triglyceride content in SHRSP. These beneficial effects of osthol could be useful for both prevention of atherosclerosis and suppression of hepatic lipid accumulation.

BENEFICIAL EFFECT OF XANTHOANGELOL, A CHALCONE COMPOUND FROM ANGELICA KEISKEI, ON LIPID METABOLISM IN STROKE-PRONE SPONTANEOUSLY HYPERTENSIVE RATS

1. Recently, we reported that 4-hydroxyderricin, one of the major chalcones in Angelica keiskei extract (ethyl acetate extract from the yellow liquid of stems), exerted hypotensive and lipid regulatory actions in stroke-prone spontaneously hypertensive rats (SHRSP). In the present study, we isolated xanthoangelol, another major chalcone in A. keiskei extract, and examined the effect of dietary xanthoangelol on blood pressure and lipid metabolism in SHRSP. 2. Six-week-old male SHRSP were fed diets containing 0.02% or 0.1% xanthoangelol (0.02 and 0.10 Xan, respectively) for 7 weeks, with free access to the diet and water. There were no significant changes in daily food intake, bodyweight or systolic blood pressure throughout the experimental period. Serum total cholesterol levels tended to decrease in the two experimental groups (albeit not significantly), which was due to a dose-dependent decrease in the cholesterol content of the low-density lipoprotein (LDL) fraction. These results suggest that dietary xanthoangelol decreases serum LDL levels. 3. In the liver, significant dose-dependent decreases in relative liver liver weight and total triglyceride content were seen in the 0.02 and 0.10 Xan groups. In addition, a significant decrease in total cholesterol content was found in the 0.10 Xan group, which may be due to an elevation of faecal cholesterol excretion in addition to the decrease in liver weight. 4. Investigation of the hepatic mRNA expression of proteins involved in lipid metabolism indicated that there was a significant increase in peroxisome proliferator-activated receptor (PPAR) alpha mRNA expression associated with the tendency for increases in acyl-coenzyme A (CoA) synthetase and acyl-CoA oxidase mRNA expression in the 0.10 Xan group, which may be responsible, at least in part, for the decrease in hepatic triglyceride content in the xanthoangelol-treated rats. In addition, a significant increase in LDL receptor mRNA expression in the 0.10 Xan group may be responsible, at least in part, for the decrease in serum LDL levels in the xanthoangelol-treated rats. 5. In conclusion, dietary xanthoangelol results in a reduction of serum LDL levels and decreases in total cholesterol and triglyceride contents in the liver of SHRSP. These beneficial effects are more effective following consumption of diet containing 0.10% xanthoangelol.

Effect of bile duct obstruction on the expression of intestinal mRNA related to cholesterol and bile acid metabolism in the rat

BACKGROUND AND AIM

The liver and small intestine play an important role in maintaining cholesterol and bile acid balance within the body. The purpose of this study was to evaluate the effect of bile duct ligation (BDL) on the expression of intestinal and hepatic genes that are important for cholesterol and bile acid metabolism.

METHODS

Rats were allocated to the BDL group or the sham operation group. Blood, liver and small intestine were obtained after 24, 72 and 168 h from both groups. Serum and hepatic lipids were measured by colorimetric assays and hepatic and intestinal mRNA related to lipid metabolism was studied by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Hepatic apolipoprotein (Apo) AIV, multidrug resistant protein (Mrp)2, adenosine triphosphate (ATP) binding cassette transporter (Abc)g5 and Abcg8 expression constantly decreased after BDL. Intestinal Apo AIV, Apo CIII, Mrp2, Abcg5 and Abcg8 expression remarkably decreased 24 h after BDL and recovered 72 and 168 h after BDL. Hepatic small heterodimer partner (Shp) expression did not change after BDL. Conversely, intestinal Shp expression remarkably decreased 24 h after BDL (16% of sham operation) and slightly recovered 168 h after BDL (58% of sham operation).

CONCLUSION

Several intestinal mRNA expressions important for lipid (Apo AIV, Apo CIII, Abcg5 and Abcg8) and bile acid (Mrp2 and Shp) metabolism were decreased in the early phase of obstructive jaundice and the expression of these intestinal mRNA recovered in the late phase of obstructive jaundice.

Alteration of the expression of adenosine triphosphate-binding cassette transporters associated with bile acid and cholesterol transport in the rat liver and intestine during cholestasis

BACKGROUND AND AIM

Multidrug resistance protein 2 (Mrp2), Mrp3, adenosine triphosphate-binding cassette transporter g5 (Abcg5) and adenosine triphosphate-binding cassette transporter g8 (Abcg8) have been identified as bile acid or cholesterol transporter in the enterocytes as well as hepatocytes. The purpose of the present study was to evaluate intestinal and hepatic adenosine triphosphate-binding cassette transporter expressions during cholestasis.

METHODS

Experiment 1: Rats were subjected to bile duct ligation or sham operation. Blood, liver and small intestines were obtained 24 and 72 h after operation. Experiment 2: Rats were divided into four groups as follows: (i) control group; (ii) diosgenin group (fed with diosgenin in diet [1%(wt/wt)] for 7 days); (iii) ethinyl estradiol group (received ethinyl estradiol [5 mg/kg daily] for 5 days); and (iv) diosgenin-ethinyl estradiol group (received ethinyl estradiol and diosgenin). After treatment, blood, bile, liver and intestines were obtained. The mRNA related to lipid and bile acid metabolism was analyzed by reverse transcription polymerase chain reaction.

RESULTS

Intestinal Mrp2 and Abcg5/Abcg8 mRNA expression remarkably decreased 24 h after bile duct ligation (43% and 61%/54% of sham operation) and recovered 72 h after bile duct ligation (103% and 95%/83% of sham operation). Intestinal Mrp3 mRNA expression did not change after bile duct ligation. Intestinal Mrp2 mRNA expression was remarkably increased in diosgenin and diosgenin-ethinyl estradiol groups in comparison with the control group. There were no significant differences in intestinal Mrp3 mRNA expression among the four groups. Hepatic Mrp3 mRNA expression was remarkably increased in the D, EE and DE groups in comparison with the control group (531%, 321% and 1160% of control, respectively, P < 0.01). Hepatic Abcg5 and Abcg8 mRNA expression decreased in ethinyl estradiol and diosgenin-ethinyl estradiol groups compared with the control group and there were no differences in intestinal Abcg5 and Abcg8 mRNA expressions among the four groups.

CONCLUSION

Bile duct ligation affects not only hepatic but also the intestinal Mrp2 and Abcg5 and Abcg8 expressions. Intestinal Mrp2 mRNA level was regulated by factor in the lumen (e.g. diosgenin feeding). Cholestasis by ethinyl estradiol treatment was enhanced by diosgenin and the increase in hepatic Mrp3 mRNA level might affect the enhancement.

Effects of pravastatin and bezafibrate on biliary lipid excretion and hepatic expression of Abcg5 and Abcg8 in the rat

BACKGROUND AND AIM

Multidrug resistance associated gene product 2 (Mdr2) is believed to have a significant role in biliary cholesterol and phospholipid secretions. Both pravastatin and bezafibrate resulted in Mdr2 induction, but increased cholesterol secretion was observed only in pravastatin treatment. To explore the mechanism, the hepatic expression of genes that are responsible for the metabolism of the lipids was studied.

METHODS

Rats were divided into three experimental groups: (i) the control group; (ii) the bezafibrate group, which was fed a diet containing 0.45% bezafibrate for 5 days; and (iii) the pravastatin group, which was fed a diet containing 0.1% pravastatin for 5 days. Serum, hepatic and biliary lipids were measured by colorimetric assays and hepatic mRNA related to lipid metabolism was studied by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

In the bezafibrate group biliary phospholipid secretion was increased although cholesterol secretion was not increased. In the pravastatin group, biliary cholesterol and phospholipid secretions were significantly increased. The biliary cholesterol/phospholipid ratio was decreased in the bezafibrate group, but the ratio did not change in the pravastatin group. Hepatic Mdr2, Abcg5 and Abcg8 mRNA expression was remarkably increased in the pravastatin group in comparison with the control group (184%, 264% and 247% of control value, respectively). In the bezafibrate group the hepatic gene expression of Mdr2 was increased (157% of control value), but there were no significant changes in hepatic Abcg5 and Abcg8 mRNA expression compared with the control group.

CONCLUSIONS

Compared with Mdr2, Abcg5 and Abcg8 seem to be more essential transporters for biliary secretion of cholesterol. Pravastatin upregulated Abcg5/Abcg8 while bezafibrate did not, which appears to explain the different effects of these compounds on biliary lipid secretion.

Phytosterol additives increase blood pressure and promote stroke onset in salt-loaded stroke-prone spontaneously hypertensive rats

1. To assess the effect of dietary phytosterol on stroke and the lifespan of salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP), we investigated the effects of the addition of phytosterol to soybean oil (phytosterol content: 0.3%) on stroke onset, lifespan following onset of stroke and overall lifespan compared with canola oil (phytosterol content: 0.9%). 2. Six-week-old male SHRSP were fed a test diet prepared by the addition of canola oil (CA diet), soybean oil (SO diet), soybean oil plus 0.6% phytosterol (SO + 0.06P diet) or soybean oil plus 4.5% phytosterol (SO + 0.45P diet) as a 10% fat source. 3. Systolic blood pressure (SBP) increased in the SO + 0.06P and SO + 0.45P groups compared with the SO group and the increase was dependent on the amount of phytosterol added, indicating that the addition of phytosterol to soybean oil may promote an increase in SBP in salt-loaded SHRSP. 4. The onset of stroke was shortest in the SO + 0.45P group and survival after the onset of stroke was shortest in the CA group. Consequently, the SO + 0.45P and CA groups showed marked lifespan shortening, indicating that a fivefold greater amount of phytosterol was required to produce an effect equivalent to that of canola oil. 5. Investigation of the mRNA expression of ATP-binding cassette (ABC) transporters involved in intestinal phytosterol absorption indicated significant decreases in the intestinal mRNA expression of Abcg5 and Abcg8 in SHRSP and Wistar-Kyoto rats compared with Wistar rats. 6. In conclusion, the addition of phytosterol to soybean oil elevated SBP and promoted the onset of stroke, which may cause a reduction in survival time. However, a fivefold greater amount of phytosterol was required to produce an effect that was equivalent to the survival time-shortening effect of canola oil. The significant decrease in the intestinal mRNA expression of Abcg5 and Abcg8 in SHRSP may be responsible, at least in part, for the unfavourable effects observed following the addition of phytosterol.

Regulation of biliary cholesterol secretion is associated with abcg5 and abcg8 expressions in the rats: effects of diosgenin and ethinyl estradiol

In this study, we evaluate the effect of diosgenin, ethinyl estradiol and these co-administration on changes of lipoprotein metabolism and expression of hepatic genes those are important for cholesterol metabolism including the recently identified abcg5 and abcg8 in male Wistar rats. Rats were subjected to four experimental groups: (1) control group, (2) diosgenin group, which was fed the diet containing 1% diosgenin for 7 days, (3) ethinyl estradiol group, which received ethinyl estradiol in a dose of 5 mg/kg daily for 5 days, (4) diosgenin-ethinyl estradiol group, which received ethinyl estradiol treatment and was fed the diet containing 1% diosgenin. Diosgenin-feeding induced the hepatic abcg5/abcg8 expressions and biliary cholesterol secretion. Ethinyl estradiol administration reduced hepatic abcg5/abcg8 expressions and biliary cholesterol secretion. There was a positive correlation between hepatic expressions of abcg5/abcg8 and biliary cholesterol secretion. These findings strongly suggest that abcg5 and abcg8 are key proteins for biliary cholesterol excretion. Diosgenin-feeding did not affect the hepatic abcg5/abcg8 expressions and biliary cholesterol excretion in ethinyl estradiol-treated rat. Serum bile acid and bilirubin were higher and biliary bile acid and bilirubin secretions were lower in diosgenin-ethinyl estradiol group than those in ethinyl estradiol group. This finding suggests that diosgenin enhances the cholestatic effect of ethinyl estradiol in the rat. In conclusion, alteration of biliary cholesterol secretion is related to the expressions of hepatic abcg5 and abcg8 in diosgenin- or ethinyl estradiol-treated rat.

Serum platelet-activating factor acetylhydrolase (PAF-AH) activity in patients with hyperbilirubinemic hepatobiliary disease

Platelet-activating factor acetylhydrolase (PAF-AH) is an enzyme that catalyzes hydrolysis of PAF and is important for regulation of serum PAF concentration. Twenty-seven patients with hyperbililubinemic hepatobiliary diseases (eight patients with liver cirrhosis, five with acute hepatitis and 14 with obstructive cholestasis) were studied. Serum PAF-AH activity was elevated in hyperbilirubinemic condition associated with liver cirrhosis, obstructive cholestasis or acute hepatitis. There was a significant correlation of serum PAF-AH activity with serum cholesterol (r=0.891, P=0.014 in liver cirrhosis, r=0.813, P=0.002 in obstructive cholestasis) or low density lipoprotein (LDL) cholesterol (r=0.771, P=0.007 in obstructive cholestasis). Serum PAF-AH activity/cholesterol ratio and PAF-AH activity/LDL cholesterol ratio were elevated in the three types of hyperbilirubinemic liver disease. LDL cholesterol increased and PAF-AH/LDL cholesterol ratio decreased in acute hepatitis after remission. On the other hand, LDL cholesterol decreased and PAF-AH/LDL cholesterol ratio did not change after treatment in obstructive cholestasis. These findings suggest that, though serum LDL is a factor influencing serum PAF-AH activity in obstructive jaundice, other factors, i.e. reduced biliary PAF-AH excretion, may also influence serum PAF-AH activity in hyperbilirubinemic hepatobiliary diseases.

Effect of obstructive jaundice on the regulation of hepatic cholesterol metabolism in the rat. Disappearance of abcg5 and abcg8 mRNA after bile duct ligation

The purpose of this study is to evaluate the effect of bile duct ligation (BDL) on changes of lipoprotein metabolism and hepatic gene expressions that are important for cholesterol metabolism. In male rats serum, very low-density lipoprotein cholesterol, low-density lipoprotein cholesterol and apolipoproteins B and E increased after 5 days of BDL compared with those of sham operation (control) group. Serum apolipoprotein A-IV concentration in the BDL group was lower than that in the control group. In both groups, there was no difference in hepatic lipid concentrations. Hepatic mRNA expressions of scavenger receptor B1, microsomal triglyceride transfer protein (mtp), HMG-coA reductase, cholesterol 7alpha-hydroxylase and multidrug resistance gene product 2 in the BDL group were significantly higher than that in the control group. The adipocyte determination and differentiation 1 mRNA expression in the BDL group was significantly lower than that in the control group. abcg5 and abcg8 mRNA expressions were remarkably decreased in the BDL group. In conclusion, in obstructive jaundice, metabolism of lipoprotein and proteins that are important for lipid metabolism are drastically changed probably for maintaining the hepatic lipid concentration. The remarkable down-regulation of the abcg5 and abcg8 may be an adaptive change reflecting the inability of biliary cholesterol excretion.

Effect of clinical clerkship on students’ attitudes toward medical learning in Japan: a case study at Kinki University School of Medicine

A 20-item questionnaire was administered to 253 physicians and 111 medical students, who did not have previous clinical clerkship experience, upon completion of their clinical clerkship. Medical students responded that they enjoyed their clinical clerkships but felt pressured and physically tired. Ninety percent of these medical students developed expectations for their career choice during their clinical clerkship. Only 18% of physicians felt that they allowed students enough chance to participate in clinical practice. We must emphasize that the success of any clinical clerkship system depends on an effective communication system between physicians and medical students.

Increased renal expression of bilirubin glucuronide transporters in a rat model of obstructive jaundice

Regulation of bilirubin glucuronide transporters during hyperbilirubinemia in hepatic and extrahepatic tissues is not completely clear. In the present study, we evaluated the regulation of the bilirubin glucuronide transporters, multidrug resistance-associated proteins (MRP)2 and 3, in rats with obstructive jaundice. Bile duct ligation (BDL) or sham operation was performed in Wistar rats. Liver and kidneys were removed 1, 3, and 5 days after BDL (n = 4, in each group). Serum and urine were collected to measure bilirubin levels just before animal killing. MRP2 And MRP3 mRNA expressions were determined by real-time RT-PCR. Protein expression of MRP2 and MRP3 was determined by Western blotting. Renal MRP2 function was evaluated by para-aminohippurate (PAH) clearance. The effect of conjugated bilirubin, unconjugated bilirubin, human bile, and sulfate-conjugated bile acid on MRP2 gene expression was also evaluated in renal and hepatocyte cell lines. Serum bilirubin and urinary bilirubin excretion increased significantly after BDL. In the liver, the mRNA expression of MRP2 decreased 59, 86, and 82%, and its protein expression decreased 25, 74, and 93% compared with sham-operated animals after 24, 72, and 120 h of BDL, respectively. In contrast, the liver expression of MRP3 mRNA increased 138, 2,137, and 3,295%, and its protein expression increased 560, 634, and 612% compared with sham-operated animals after 24, 72, and 120 h of BDL, respectively. On the other hand, in the kidneys, the mRNA expression of MRP2 increased 162, 73, and 21%, and its protein expression increased 387, 558, and 472% compared with sham-operated animals after 24, 72, and 120 h of BDL, respectively. PAH clearance was significantly increased after BDL. The mRNA expression of MRP2 increased in renal proximal tubular epithelial cells after treatment with conjugated bilirubin, sulfate-conjugated bile acid or human bile. Upregulation of MRP2 in the kidneys and MRP3 in the liver may be a compensatory mechanism to improve bilirubin clearance during obstructive jaundice.

Endoscopic band ligation for control of nonvariceal upper GI hemorrhage: comparison with bipolar electrocoagulation

BACKGROUND

Despite advances in endoscopic treatment methods for upper GI hemorrhage, hemostasis is often difficult to achieve. This study evaluated the usefulness of endoscopic band ligation for upper GI hemorrhage exclusive of hemorrhage from chronic gastroduodenal ulcer and varices.

METHODS

This prospective study included 27 patients who underwent endoscopic band ligation and 31 patients in whom bipolar electrocoagulation was performed for upper GI hemorrhage. In both groups, the causes of hemorrhage included Dieulafoy's ulcer, Mallory-Weiss tear, gastric ulcer after polypectomy, and gastric angiodysplasia. Patients with esophageal varices and those with chronic gastroduodenal ulcer were excluded.

RESULTS

Hemostasis was achieved in all 27 patients in the endoscopic band ligation group and in 26 of 31 patients (83.9%) in the bipolar electrocoagulation group. The median procedure time required for achieving hemostasis was 17.0 minutes (interquartile range: 11.5-23.5) in the endoscopic band ligation group versus 27.0 minutes (interquartile range: 20.5-40.0) in the electrocoagulation group. No major complications occurred in either group.

CONCLUSION

Endoscopic band ligation is efficient, simple, and safe. Therefore, this technique should be considered as a treatment option for nonvariceal, nonchronic gastroduodenal ulcer upper GI hemorrhage.

Increased expression of multidrug resistance-associated protein 1 (mrp1) in hepatocyte basolateral membrane and renal tubular epithelia after bile duct ligation in rats

Components of the multidrug resistance-associated protein (mrp) family mediate the adenosine triphosphate (ATP)-dependent transport of conjugated organic anions in the liver. Of these, mrp1 and mrp2 have been shown to have similar substrate specificity and nucleotide sequence. The intracellular localization and distribution of mrp1 under normal condition and cholestasis have not been as yet completely elucidated. To clarify this point, in the present study we evaluated the intracellular localization of mrp1 in rat liver and kidney after bile duct ligation (BDL). Bile duct was ligated in Wistar rats. Sequential staining of mrp1 by immunofluorescence was carried out in rat liver and kidneys 1, 3, and 5 days after bile duct ligation using confocal laser scanning microscopy. Weak granular staining of mrp1 was observed in cytoplasm of control rat hepatocytes. In addition to increased cytoplasm staining of mrp1, belt-and granule-like staining of mrp1 in basolateral membrane of hepatocytes was also shown after BDL. Furthermore, mrp1 immunofluorescence increased over time after BDL. No specific immunoflurescence of mrp1 was detected in control rat kidney. However, mrp1-positive staining was observed in epithelia of some renal tubules after BDL. This study showed that mrp1 immunofluorescence increased in hepatocyte basolateral membrane and cytoplasm and epithelia of some renal tubules after BDL. This increased mrp1 expression may be an adaptive response to impairment of hepato-biliary organic anion transport during obstructive cholestasis.

Two cases of histopathologically advanced (stage IV) early gastric cancers

We report two cases of early gastric cancer with distant metastases (stage IV). At our institute 1428 cases of primary gastric cancer were resected between 1980 and 1997; 536 were diagnosed as early gastric cancer based on the resected specimens (304 cases of mucosal cancer, Tis--TNM classification--and 232 of submucosal cancer, T1). 528 of these 536 cases were classified as histological stage I, six as stage II, none as stage III and two as stage IV. The incidence of stage IV early gastric cancer was 0.14% of all gastric cancers and 0.37% of the early gastric cancers. The two patients with stage IV early gastric cancer were women. Both tumors were defined as early cancer because they were confined to the submucosa. One was a type 0 IIc + III early cancer, histologically classifiable as a small, moderately differentiated adenocarcinoma (tub2 according to the Japanese Classification of Gastric Carcinoma, G2; TNM classification: ICD-O C16), size 10 x 8 mm; the other was a surface spreading type 0 IIc, classifiable as a signet-ring cell carcinoma (sig, G3), size 50 x 35 mm. Stage IV factors were N3 in the first and ovarian metastasis (Krukenberg tumor) in the second case.

Recent advances in bilirubin metabolism research: the molecular mechanism of hepatocyte bilirubin transport and its clinical relevance

Bilirubin is taken up from blood into hepatocytes by sinosuidal membrane transporters and then excreted into bile through the bile canalicular membrane mainly as bilirubin glucuronides. (1) Mechanism of bilirubin uptake into hepatocytes: many organic anions are incorporated into hepatocytes by organic anion transporting polypeptides (rat, oatp1, oatp2, oatp3; human, OATP), liver-specific transporter (rlst/HLST), and/or by organic anion transporters (OAT2, OAT3). Oatp1 and HLST transport bilirubin monoglucuronide. However, a transporter of unconjugated bilirubin in the sinusoidal membrane has not as yet been identified. Unconjugated bilirubin may also go across the hepatocyte sinusoidal membrane by a diffusion process. (2) Intrahepatic transport and conjugation of bilirubin: ligandin carries bilirubin to the endoplasmic reticulum (ER) of hepatocytes. In the ER, bilirubin is conjugated by bilirubin uridine diphosphate (UDP)-glycosyltransferase (bilirubin UGT; UGT1A1) to form mono- and diglucuronides of bilirubin. (3) Transport mechanism of bilirubin glucuronides across the hepatocyte canalicular membrane: at the canalicular membrane, bilirubin glucuronides are excreted into bile by multidrug resistance-associated protein 2 (MRP2), a member of the ATP-binding cassette transporter family. (4) Regurgitation of bilirubin glucuronides into blood: MRP3, which is located in the lateral membrane, transports bilirubin glucuronides into blood under conditions of impaired biliary bilirubin excretion.

Characterization of ATP-dependent monoglucuronosyl bilirubin transport across rat canalicular membrane vesicles

Bilirubin conjugates are secreted from hepatocytes into bile. Monoglucuronosyl bilirubin is an endogenous substrate for the multidrug resistance protein 2, which is located in rat hepatocyte canalicular membrane. We have characterized this ATP-dependent transport using rat canalicular membrane vesicles. Monoglucuronosyl bilirubin, 3H-labeled in the glucuronosyl moiety, was synthesized enzymatically using recombinant UDP-glycosyltransferase 1A1, and was stabilized with ascorbate. The rate for ATP-dependent transport of monoglucuronosyl bilirubin (at 0.5 µM) was 7.3+/-1.1 pmol mg protein(-1) min(-1) and the K(m) value was 1.3+/-0.4 µM. This is the first time to demonstrate this kinetic constant of monoglucuronosyl bilirubin for the rat hepatocyte canalicular membrane. The K(m) value is similar to one for recombinant rat multidrug resistance protein 2.