Biomedical subjects

Miyuki Nakaji

Publications and source records attributed to Miyuki Nakaji.

15 recordsLinked to original sources

PubMed2005

Multiple hypervascular liver nodules in a heavy drinker of alcohol.

A case of hypervascular nodules in the liver, but without hepatitis B or C virus infection in a 38-year-old woman with a history of alcohol abuse is presented. An ultrasound disclosed 1-2-cm hypoechoic tumors in the right and left lobes. Magnetic resonance imaging showed high-intensity tumors at both the T1-weighted and T2-weighted sequences. Incremental dynamic computed tomography and hepatic angiography revealed hypervascular tumors. Ultrasound-guided needle biopsy revealed no evidence of hepatocellular carcinoma, metastatic liver cancer, hemangioendothelioma, inflammatory pseudotumors or pseudolymphoma, but demonstrated stellate-scar fibrosis septa, which contained small unpaired arteries without hyperplasia dividing the nodule. Moreover, marked pericellular fibrosis, neutrophilic infiltration and Mallory bodies were observed in the cytoplasm. There was no evidence of bile duct proliferation. From these findings, the diagnosis of alcohol-induced fibrosis, distinctly different from focal nodular hyperplasia, was tenable. Further studies may provide insights into the pathogenesis of nodule formation and hypervascularity in heavy drinkers of alcohol.

Adult↗

PubMed2004

Expression and localization of ecto-nucleotide pyrophosphatase/phosphodiesterase I-1 (E-NPP1/PC-1) and -3 (E-NPP3/CD203c/PD-Ibeta/B10/gp130(RB13-6)) in inflammatory and neoplastic bile duct diseases.

Ecto-nucleotide pyrophosphatase/phosphodiesterase-I enzyme (E-NPP) consists of three closely related molecules: E-NPP1, E-NPP2 and E-NPP3. We investigated the expression and localization of E-NPP1 and -3 in human inflammatory and neoplastic bile duct diseases. Immunohistochemically E-NPP1 was located on the apical cytoplasmic side of cancer cells, whereas E-NPP3 was located in the apical plasma membrane. Western blot analysis revealed that the expression of E-NPP3, but not E-NPP1, was higher in tumor tissues than in surrounding tissues and the specific form of the E-NPP3 protein was readily detected in the sera of bile duct carcinoma (BDC) patients. Furthermore, it was confirmed that E-NPP3 was associated with migration ability by using of NIH3T3 cells that stably transfected with E-NPP3 cDNA. These results suggest that E-NPP3 is involved in the infiltration of neoplastic BDC and is possible to be a tumor marker.

Animals↗

PubMed2004

Apoptotic pathway related to oval cell proliferation.

BACKGROUND AND AIM: Oval cells, liver stem cell-derived cells, are generated from the liver periportal region and spread into the parenchyma by an autocrine signaling pathway. The mechanism behind how oval cells take their place among packed silent hepatocytes, however, is not well understood. We hypothesized that apoptosis involves a decrease in hepatocytes surrounding oval cells. METHODS: Male Fisher rats were treated using the AAF/PH protocol to induce oval cells in the liver. Apoptosis was assessed by measuring the activity of caspase-3, -8 and -9, and apoptosis-related molecules such as caspase-3, Fas, Fas-L and Bax were also assessed by immunohistochemical analysis and reverse transcriptase-polymerase chain reaction (RT-PCR). Apoptosis was confirmed by TUNEL staining. Regarding antiapoptotic factors, nuclear factor-kappaB (NF-kappaB) DNA binding activity and proliferating cell nuclear antigen (PCNA) expression were examined. RESULTS: NF-kappaB elevated at the early stage of oval cell proliferation. Conversely, caspase activity increased after NF-kappaB elevation. The mRNA of caspase-3, Fas, Fas-L and Bax was induced during and after AAF/PH treatment. Immunohistochemically, oval cells lacked the expression of these proteins, whereas the hepatocytes, particularly those surrounding oval cells, expressed strongly. CONCLUSIONS: The present study suggests that the apoptosis in hepatocytes through both extrinsic and intrinsic pathways mediates oval cell proliferation.

Animals↗

PubMed2004

Early response to interferon alpha treatment and long-term clinical outcome in Japanese patients with chronic HBV genotype C infection.

Genotype C of hepatitis B virus (HBV) has been shown to be associated with a poor clinical outcome and less favorable response to interferon (IFN) alpha therapy compared to genotype B. We evaluated the response to IFN alpha therapy and long-term clinical outcome in Japanese patients with chronic active HBV genotype C infection. Thirty Japanese patients with chronic active hepatitis who received natural IFN alpha therapy were followed for 2-12 years (mean 5.9 years). Twenty-four patients were treated short-term (daily for 4 weeks at a mean total dosage of 174 million units) and 6 patients were treated long-term (total of 26 weeks at a mean total dosage of 687 million units). Twelve of 30 (40%) patients had an antiviral response at 6 months after therapy. Clinical data before treatment in both responders and non-responders were comparable. Although not significant, responders tended to have younger age, a higher serum transaminase level, a lower frequency of precore mutation (G1896A) (67% vs. 92%) and a higher frequency of core promoter mutation (A1762T/G1764A) (89% vs. 58%) than non-responders. The patients treated long-term responded significantly better than those treated short-term (83% vs. 29%, P=0.026). Up to 12 years after therapy, a higher percentage of responders than non-responders had sustained clearance of HBeAg with seroconversion and normalization of transaminase concentration at the followed end point (83% vs. 17%, P<0.001). Two non-responder patients had cirrhosis after long-term follow-up. One non-responder patient died of hepatocellular carcinoma 8 years after IFN therapy; except in this patient there was no development of decompensated cirrhosis. Early responsiveness to IFN alpha therapy in Japanese patients with chronic active HBV genotype C infection improves the long-term clinical outcome.

Adult↗

PubMed2003

IFN-alpha prevents the growth of pre-neoplastic lesions and inhibits the development of hepatocellular carcinoma in the rat.

Interferon (IFN)-alpha treatment is a common therapy for chronic viral hepatitis and contributes to preventing hepatocarcinogenesis. However, it is not clear whether IFN-alpha directly inhibits the clonal expansion of pre-neoplastic hepatocytes. To clarify the mechanism by which IFN-alpha prevents hepatocarcinogenesis, we examined the effect of IFN-alpha in a chemically induced hepatocarcinogenesis model initiated by diethylnitrosamine (DEN) and promoted by 2-acetylaminofluorene (2-AAF) and partial hepatectomy, in which hepatocellular carcinoma (HCC) arises through pre-neoplastic foci without inflammation or fibrosis. The protocols of IFN-alpha administration were started simultaneously with chemical initiation and lasted for either 4 or 40 weeks. The pre-neoplastic foci and neoplastic HCC were evaluated at 4 or 40 weeks after chemical initiation, respectively. The effects of IFN-alpha were assessed by the expression of tumor-related genes and cell cycle-related genes in the pre-neoplastic foci, using immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). As a result of IFN-alpha treatment, the numbers and average volume of pre-neoplastic foci were reduced. The proliferating cell nuclear antigen index and the expression of G(1) cyclins were also reduced in the pre-neoplastic foci in the IFN-treated group. The expression of p21, which is an inhibitor of cyclin-kinase complexes was higher in the foci of the IFN-treated group, while p53 expression was not altered in this group, compared with the control group. IFN-alpha also suppressed the tumor development at 40 weeks after initiation. And in the long-term IFN-alpha-treated group, both the tumor numbers and average tumor size were markedly more reduced than those in the short-term-treated group. Therefore, it was demonstrated that longer treatment with IFN-alpha was more effective, compared with shorter treatment. In conclusion, it was shown that IFN-alpha directly prevented and delayed hepatocarcinogenesis through the suppression of pre-neoplastic cell proliferation and that it may partially depend on p21 induction through a p53-independent pathway.

Animals↗

PubMed2003

An outbreak of fulminant hepatitis B in immunocompromised hemodialysis patients.

BACKGROUND: We aimed to clarify the pathogenesis of an outbreak of fulminant hepatitis B in hemodialysis (HD) patients whose compromised cell-mediated immunity in turn contributed to chronic hepatitis B virus (HBV) carriage. METHODS: Five consecutive adult HD patients with acute hepatitis B were evaluated. Viral genotype, mutations, and HBV-DNA levels were studied in relation to viral clearance, liver disease severity, and liver histology by immunostaining. RESULTS: All five patients had hepatitis B surface antigen (HBsAg) genotype C, a G-to-A stop codon mutation at nucleotide (nt) 1896 in the precore region, an A-to-T mutation at nt 1762 and an G-to-A mutation at nt 1764 in the basal core promoter. The possible index patient, who suffered from liver cirrhosis, had HBsAg genotype C, anti-hepatitis B envelope (HBe), and these mutations. The level of HBV-DNA declined by about 10 percent per week and no difference in viral kinetics between the patients who died and the survivor was found, irrespective of therapies. The amount of liver cell apoptosis, as assessed by single-stranded DNA, was scarce. The risk of fulminant hepatic failure did not correlate with the preexistent liver histopathological changes. Acute HBV superinfection was associated with hepatitis C virus (HCV) elimination and increased mortality. CONCLUSIONS: This outbreak of fulminant hepatitis B suggests that HD patients can foster highly virulent HBV strains (possibly owing to their compromised immune responses), which may place others at risk of severe, life-threatening acute liver damage and at increased risk of mortality if chronic carriers of HCV should be infected. We aimed to clarify the pathogenesis of an outbreak of fulminant hepatitis B in hemodialysis (HD) patients whose compromised cell-mediated immunity in turn contributed to chronic hepatitis B virus (HBV) carriage.

Aged↗

PubMed2003

Hepatitis B virus DNA in anti-HBe-positive asymptomatic carriers.

OBJECTIVES: We examined the level of hepatitis B virus (HBV) DNA and the mutations in the precore, core and polymerase regions of HBV in sera from anti-HBe-positive asymptomatic carriers (ASC). METHODS: The amount of HBV DNA was determined semiquantitatively by mutation site-specific assay in sera from 19 anti-HBe-positive ASC and 31 HBeAg-positive patients with chronic liver disease (CLD). The mutations in the precore, core and polymerase (terminal protein) regions, spanning 1,037 nucleotides, of HBV in sera from three cases each of anti-HBe-positive ASC, HBeAg-positive ASC and HBeAg-positive CLD were examined by directly sequencing the amplified HBV DNA. RESULTS: The level of HBV viremia in anti-HBe-positive ASC was significantly lower than that in HBeAg-positive CLD patients (p < 0.01). By sequence analysis, there were a few missense mutations detected in HBeAg-positive ASC and HBeAg-positive CLD patients. In contrast, many mutations, especially in the central or N-terminal half of the core region and N-terminal part of the polymerase region, were detected in anti-HBe-positive ASC. CONCLUSION: Mutations not only in the precore/core region, but also in the polymerase region of HBV might cause damage to some important functions for efficient replication of HBV and be involved in the reduced amount of HBV in anti-HBe-positive ASC.

Adult↗

PubMed2003

Different apoptotic regulation of TRAIL-caspase pathway in HBV- and HCV-related hepatocellular carcinoma.

Human hepatocellular carcinoma (HCC) appears to be strongly associated with apoptosis and its breakdown may be involved in the occurrence of HCC. Like the Fas/Fas-L system, the tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) transduces apoptosis in a number of cancers; it is also a clinical candidate for cancer therapy. To examine its applicability in future therapy, the apoptotic pathway through TRAIL was investigated in HBV- and HCV-related HCC that have different mechanisms of hepatocarcinogenesis. Caspase-3 activity and the expression of four types of TRAIL receptor mRNAs were quantitated in tumor and contiguous non-tumor tissues obtained from 27 patients with HCC (HBV-related in 10; HCV-related in 17). The expression of caspase-3 and TRAIL receptors was also examined immunohistochemically. A significantly positive correlation was observed between caspase-3 activity and TRAIL-R1, -R2. Caspase-3 activity and TRAIL-R1, -R2 expression in tumor tissue were significantly lower than those in non-tumor tissue in HBV-related HCC. Some HCV-related HCC cases, however, demonstrated elevated caspase-3 activity and TRAIL-R1, -R2 expression in tumor tissue. HBV-related HCC demonstrated significantly suppressed caspase-3 activity, signifying apoptosis. Both TRAIL-R1 and -R2 showed coefficient correlation with caspase-3 activity, and were strongly associated with apoptosis in human HCC.

Apoptosis↗

PubMed2003

A case of well-differentiated hepatocellular carcinoma arising in primary biliary cirrhosis.

Primary biliary cirrhosis (PBC) is a chronic progressive, autoimmune liver disease that increases the risk of hepatobiliary malignancies at a late stage. We report a 66-year-old woman with PBC combined with hepatocellular carcinoma (HCC) accompanied by hypoglycemia. Two large tumors were detected on admission and the patient died because of tumor rupture and subsequent liver failure. Histological analysis revealed well-differentiated HCC in both of the tumors. Sometimes the patient had suffered from hypoglycemic attacks of unknown origin, but serum immunoreactive insulin (IRI) was within the normal range. It was interesting that such large well-differentiated hepatocellular carcinomas were generated in PBC.

Aged↗

PubMed2002

Development of multicentric hepatocellular carcinoma after completion of interferon therapy.

We report a case of multicentric hepatocellular carcinoma that developed in a 74-year-old man 3 and 6 years after interferon (IFN) treatment for chronic hepatitis C, despite sustained virologic, biochemical, and histological improvement. Initially, serum hepatitis C virus RNA was positive and the patients' serum level of alanine aminotransferase (ALT; 82 IU/ml) was abnormal. Hepatitis B virus (HBV) in the serum was negative for surface antigen, surface antibody, core antibody, and DNA. The patient was started on 10 x 10(6) international units (IU) of IFNalpha, 3 days a week for a total of 24 weeks. After the IFN therapy, the patient demonstrated a normal serum ALT level, and was continuously negative for HCV-RNA, and histology improved from chronic active hepatitis to chronic persistent hepatitis. Follow-up studies with ultrasonography (US) every 3 months and computed tomography (CT) every 6 months revealed no space-occupying lesion (SOL) for 3 years after IFN treatment.US-guided biopsies of two 15-mm hypoechoic SOLs in segments eight (S8) and seven (S7) 34 and 74 months, respectively, after IFN treatment showed well-differentiated hepatocellular carcinoma (HCC). Clinical data, imaging studies, and histologic examinations showed that both tumors were multicentric HCC. Further studies may provide insights into the possible role of HCV in hepatocarcinogenesis in patients demonstrating HCV eradication by IFN treatment.

Aged↗

PubMed2002

CEA producing primary hepatic carcinoid.

Imaging studies of a hepatic tumor in a 53-year-old woman with elevated serum levels of neuron-specific enolase (NSE), carcinoembryonic antigen (CEA) and 5-hydroxyindole acetic acid (5HIAA) revealed a hypervascular tumor in the right lobe. Grossly, the brownish tumor was measured 13.5x12 cm with four daughter nodules. Microscopically, the majority of these columnar and round tumor cells had ribbon-or rosette-like patterns with the expression of neuroendocrine marker proteins, such as Grimelius, NSE, chromogranin A, and synaptophysin, and moderate expression of CEA but without the expression of cytokeratin nos 7,8,14,18,19 and OV-6; the minority had glandular patterns with a strong expression of CEA but without the expression of cytokeratin nos 7,8,14,18,19 and OV-6. Ultrastructurally, most tumor cells contained populations of electron-dense core granules ranging between 100 and 200 nm in diameter. After hepatectomy, serum CEA, NSE, and 5HIAA reverted to normal ranges and persisted for 19 months. These findings suggested that the diagnosis of primary hepatic carcinoid was tenable and that the tumor might derive from hepatic stem cells which acquired the additional nature of producing CEA without cytokeratins characteristic of hepatocytes or bile duct cells. Some molecular based approaches have attributed unique biological behavior and histogenesis to this carcinoid tumor.

Journal Article↗

PubMed2002

Eosionophilic pseudotumor of the liver due to Ascaris suum infection.

A case of eosinophilic pseudotumor of the liver due to Ascaris (A) suum is described in a 34-year-old-man with a high serum level of immunoglobulin E and hypereosinophilia ascribed to a history of atopic dermatitis since childhood. Multiple hepatic hypoechoic nodules detected by ultrasound were confirmed as low-density nodules on computed tomography (CT), and as low and high signal intensity lesions on T1-and T2-weighted magnetic resonance imaging (MRI), respectively. CT during arteriography (CTA) and arterial portography revealed multiple nodules with ring-shaped enhancement and perfusion defect, respectively. Biopsied liver tissue specimens did not contain tumor cells or atypical cells; instead, they showed marked infiltration of eosinophils with necrosis and Charcot-Leyden crystals in the portal tracts and hepatic sinusoides, suggesting parasitic infection, although neither larvae nor eggs were detected. The diagnosis of visceral larva migrans (VLM) due to A. suum was based on immunoserological tests. The patient was a habitual consumer of raw bovine liver, which may explain the A. suum infection. After drug therapy with albendazole, the hypoechoic nodules disappeared. Differential diagnoses and the possible transfection route of A. suum are discussed.

Journal Article↗

PubMed2002

Histological grading and staging in chronic hepatitis: its practical correlation.

Although the histological features of various causes of chronic liver disease have been well described, usually the inflammatory activity of the disease is important after the cause has been established. Some patients have co-infection or concomitant liver disease and on occasion it is difficult to decide the treatment. In order to clarify the histological differences, we investigated the inflammatory activity among autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), chronic hepatitis C (CHC) and chronic hepatitis B (CHB) in a standardized way using the modified histological activity index (HAI). According to the modified HAI, inflammatory activity is divided into four categories; categories A/D explains portal/periportal inflammation and categories B/C explains lobular activity. The inflammatory score of AIH tended to be greater in all categories from the early stage of fibrosis, whereas scores of PBC were lower, except for portal inflammation. Chronic hepatitis C patients had portal or periportal inflammation, and their inflammatory scores were linked to the development of fibrosis. Chronic hepatitis B patients tended to have severe lobular injury, but did not have a relationship between the inflammatory score and their stage. To know the distribution of inflammation using the modified HAI scoring system may be helpful and convenient in evaluating patients with chronic inflammatory liver disease.

Adult↗

PubMedDate not supplied

Response to interferon-alpha in chronic hepatitis B with and without precore mutant strain detected by mutation site-specific assay.

GOALS: We investigated whether the presence of precore mutant (stop codon mutation at codon 28) affects the response to interferon-alpha in patients with chronic hepatitis B. BACKGROUND: Mutations of hepatitis B virus (HBV) may influence the response to treatment. The association of precore mutant with the response to interferon is controversial. STUDY: Thirty-one Japanese patients with hepatitis B e antigen-positive chronic hepatitis were treated with natural interferon-alpha. HBV DNA with the precore mutation was assayed in serum using a mutation site-specific assay before and after treatment. RESULTS: Before treatment, precore mutant was detected in 22 cases (group A) and not detected in 9 cases (group B). Serum HBV DNA level before treatment was not different between the 2 groups. At the end of treatment, serum HBV DNA was decreased to undetectable levels in 13% (4 of 31). Six months after treatment, the percentage of cases with loss of hepatitis B e antigen and a decrease in the transaminase level to within the normal range was significantly higher in group B than in group A (67%, 18%, P = 0.015). CONCLUSIONS: Chronic hepatitis without precore mutant strain before treatment is more responsive to IFN-alpha.

Adult↗

PubMedDate not supplied

Evaluation of the therapeutic effect using MD-CT immediately after RFA for HCC.

BACKGROUND/AIMS: Radiofrequency ablation (RFA) is an effective modality for treatment of hepatocellular carcinoma (HCC), because it can induce large coagulation necrosis in a few sessions. The aim of this study is to evaluate whether we can assess the therapeutic effect of RFA immediately after RFA. METHODOLOGY: Twenty-one patients (25 nodules) with HCC undergoing RFA treatment were enrolled in this study. Fourteen patients were treated with combination therapy of lipiodol chemoembolization and RFA, while 7 patients were treated with RFA alone. Dynamic computed tomography (CT) using multidetector row helical CT (MD-CT) was performed before, immediately after and 1 week after RFA. Simultaneously, multiplanar reconstruction (MPR) images were also obtained for comparison. RESULTS: With or without chemoembolization, the size of coagulated necrosis was almost the same between the time immediately after and 1 week after RFA. The therapeutic effect was able to be evaluated by dynamic CT scans immediately after RFA in all patients. Moreover, MPR images facilitate the detailed evaluation of the therapeutic effect. CONCLUSIONS: Examination of dynamic CT using MD-CT immediately after RFA is useful to evaluate the therapeutic effect and may enable a shorter hospital stay.

Aged↗