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1.
Microscopy (Oxf) ; 63(3): 249-54, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24737830

RESUMO

Identification of local strains is crucial because the local strains largely influence the ferroelectric property of BaTiO3. The effects of local strains induced by external pressures on the Ti-L2,3 electron energy-loss near-edge structure (ELNES) of BaTiO3 were theoretically investigated using first-principles multiplet calculations. We revealed that the effects appear in the position of the spectral threshold, namely the spectrum shifts to lower and higher energy sides by the tensile and compressive pressures, respectively. We concluded that conventional ELNES observations can identify only large strains induced by -10 GPa, and 0.1 eV energy resolution is required to identify ±2% of strains.

2.
Artigo em Inglês | MEDLINE | ID: mdl-23007773

RESUMO

The valences of manganese and vanadium oxides in multi-layer ceramic capacitors (MLCCs), sintered under a reducing atmosphere, were investigated using electron paramagnetic resonance; insulation resistance degradation was analyzed using impedance spectroscopy in highly accelerated lifetime tests to clarify the influences of manganese and vanadium on both the electrical properties and microstructure of MLCCs. The Mn(2+) was stable in the reducing-atmospheresintered MLCCs and formed a grain boundary. Vanadium mitigated insulation resistance degradation and increased the reliability of the MLCCs. Although V4+ was detected in MLCCs that had 0.20 mol% and 0.30 mol% of added vanadium, the electrical properties were dependent upon other ions, e.g., V(3+) or V(5+). All vanadium ions except for V(4+) decreased the insulation resistance of ceramic/electrode interface. This is because vanadium reduces electric field concentration at the ceramic/ electrode interface and delays the onset of oxygen vacancy migration in the early stages of a highly accelerated lifetime test.

3.
Lab Invest ; 89(12): 1374-86, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19823170

RESUMO

The peribiliary inflammation of cholangiopathy affects the physiological properties of biliary epithelial cells (cholangiocyte), including bicarbonate-rich ductular secretion. We revealed the upregulation of annexin A2 (ANXA2) in cholangiocytes in primary biliary cirrhosis (PBC) by a proteomics approach and evaluated its physiological significance. Global protein expression profiles of a normal human cholangiocyte line (H69) in response to interferon-gamma (IFNgamma) were obtained by two-dimensional electrophoresis followed by MALDI-TOF-MS. Histological expression patterns of the identified molecules in PBC liver were confirmed by immunostaining. H69 cells stably transfected with doxycyclin-inducible ANXA2 were subjected to physiological evaluation. Recovery of the intracellular pH after acute alkalinization was measured consecutively by a pH indicator with a specific inhibitor of anion exchanger (AE), 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS). Protein kinase-C (PKC) activation was measured by PepTag Assay and immunoblotting. Twenty spots that included ANXA2 were identified as IFNgamma-responsive molecules. Cholangiocytes of PBC liver were decorated by the unique membranous overexpression of ANXA2. Apical ANXA2 of small ducts of PBC was directly correlated with the clinical cholestatic markers and transaminases. Controlled induction of ANXA2 resulted in significant increase of the DIDS-inhibitory fraction of AE activity of H69, which was accompanied by modulation of PKC activity. We, therefore, identified ANXA2 as an IFNgamma-inducible gene in cholangiocytes that could serve as a potential histological marker of inflammatory cholangiopathy, including PBC. We conclude that inducible ANXA2 expression in cholangiocytes may play a compensatory role for the impaired AE activity of cholangiocytes in PBC in terms of bicarbonate-rich ductular secretion and bile formation through modulation of the PKC activity.


Assuntos
Anexina A2/metabolismo , Antiporters/metabolismo , Ductos Biliares/fisiopatologia , Células Epiteliais/metabolismo , Cirrose Hepática Biliar/metabolismo , Linhagem Celular , Regulação da Expressão Gênica , Humanos , Interferon gama/metabolismo , Cirrose Hepática Biliar/fisiopatologia , Proteína Quinase C/metabolismo , Proteômica , Transdução de Sinais
4.
J Gastroenterol ; 44(4): 329-37, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19271116

RESUMO

BACKGROUND: Recent studies have shown that indigenous hepatitis E virus (HEV) strains cause hepatitis E in industrialized countries. We aimed to clarify the characteristics of HEV infection in sporadic hepatitis patients during the last decade in Miyagi, northeast Japan. METHODS: We analyzed 94 serum samples obtained from acute or fulminant hepatitis patients of non-A, non-B, and non-C etiology between 1999 and 2008. Antibody to HEV (anti-HEV) was assayed, and patients who were positive for IgM- and/or IgA-class anti-HEV were diagnosed with hepatitis E. HEV RNA was tested in these patients, and phylogenetic analysis was performed. The occurrence of hepatitis E was compared with that of hepatitis A. RESULTS: Eight acute hepatitis patients (8.5%) were diagnosed with hepatitis E, and HEV RNA was detectable in seven patients. Five isolates of HEV were segregated into genotype 3 and the remaining two isolates into genotype 4. The year of the occurrence of hepatitis E was distributed almost equally from 1999 to 2008, whereas the cases of acute hepatitis A (n = 16) have decreased markedly in the last several years. In 2004-2008, the occurrence of hepatitis E was greater than that of hepatitis A (five cases vs. one case). As for seasonality, hepatitis E occurred more frequently from September to December than hepatitis A (five cases vs. four cases), although less frequently from January to April (one case vs. seven cases). CONCLUSION: The occurrence of hepatitis E has not decreased during the last decade in northeast Japan, in contrast to hepatitis A.


Assuntos
Vírus da Hepatite E/imunologia , Hepatite E/epidemiologia , RNA Viral/sangue , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Hepatite A/epidemiologia , Hepatite E/imunologia , Vírus da Hepatite E/genética , Humanos , Imunoglobulina A/sangue , Imunoglobulina M/sangue , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estações do Ano , Fatores de Tempo , Adulto Jovem
5.
J Gastroenterol ; 43(9): 720-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18807134

RESUMO

BACKGROUND: Many studies have reported the efficiency of transient elastography, a noninvasive, reproducible, and reliable method for predicting liver fibrosis, in patients with chronic hepatitis C (CHC) and B (CHB), but there are few reports about nonviral chronic liver disease (CLD) such as primary biliary cirrhosis (PBC), nonalcoholic steatohepatitis (NAFLD), and autoimmune hepatitis (AIH). We therefore compared the efficiency of transient elastography between CHC and nonviral CLD. METHODS: We assessed the accuracy of liver stiffness measurement (LSM) using Fibroscan, and compared these values with those of hyaluronic acid, type 4 collagen, platelet count, prothrombin index, and AST/platelet ratio index (APRI) as indices for the diagnosis of liver fibrosis in 114 patients with a variety of chronic liver diseases: CHC (n = 51), CHB (n = 11), NAFLD (n = 17), PBC (n = 20), and AIH (n = 15). The histology was assessed according to the METAVIR score by two pathologists. RESULTS: The number of fibrosis stage (F0/1/2/3/4) with CHC was 9/15/12/6/10, and that with nonviral CLD was 10/21/11/4/6, respectively. The ability, assessed by area under receiver operating characteristic (AUROC) curve, to predict liver fibrosis F >or= 2 for LSM, HA, type 4 collagen, platelet count, prothrombin index, and APRI, was 0.92, 0.81, 0.87, 0.85, 0.85, and 0.92 in CHC patients, respectively; and 0.88, 0.72, 0.81, 0.67, 0.81, and 0.77 in nonviral CLD patients, respectively. CONCLUSIONS: In patients with nonviral CLD, LSM was most helpful in predicting significant fibrosis (F >or= 2). Transient elastography is a reliable method for predicting significant liver fibrosis, not only in CHC patients but also in nonviral CLD patients.


Assuntos
Técnicas de Imagem por Elasticidade , Cirrose Hepática/diagnóstico , Fígado/patologia , Biópsia por Agulha , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/patologia , Feminino , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/patologia , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/patologia , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/patologia , Humanos , Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática Biliar/patologia , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade
6.
Hepatol Res ; 38(8): 842-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18498361

RESUMO

We report a case of a HIV and hepatitis B virus (HBV)-co-infected patient to whom entecavir (ETV) was administered initially before the notification regarding the potential mutagenesis effect on HIV against the nucleoside analog. Since initial evaluations indicated the advanced stage of chronic hepatitis B and preserved numbers of peripheral CD4+ lymphocytes without the manifestation of immunodeficiency, priority was given to the management of HBV. We started HBV therapy with ETV at a dose of 0.5 mg daily without using any HIV drugs. The viral loads of both HBV and HIV-1 decreased gradually during the 5 months following the initial administration of ETV. HBV was well controlled by the gradual replacement of ETV with highly-active antiretroviral therapy against HIV with a regimen including atazanavir, emtricitabine, and tenofovir. HBV was genotyped as A2 with the quasispecies pool consisting of the -1G precore/core deletion mutant strain.

7.
J Clin Virol ; 41(4): 301-4, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18291715

RESUMO

Although many extrahepatic manifestations have been described in patients with acute or chronic hepatitis B, there are few reports about neurological disorders. We describe a 55-year-old man who contracted acute hepatitis B virus (HBV) infection and transverse myelitis. His neurological findings were gradually reduced along with the recovery from hepatitis. The cerebrospinal fluid (CSF) was revealed to be positive for HBsAg and HBV DNA. Full-length sequences of HBV in his serum and CSF were determined, and it was revealed that these two isolates had mutations at nucleotide (nt) 1762/1764 in the core promoter region and nt 1896 in the precore region. They were identical to each other except for two ambiguous codes at nt 2020 and 2631 in the CSF isolate. After cloning of the amplicons, substitutions at nt 2020 and 2631 were found in 6 (38%) of the 16 CSF clones. One clone of the 6 CSF clones had an additional substitution at nt 2119. These substitutions were not found in 16 serum clones. The presence of HBV clones unique to CSF suggests that HBV was a possible causative agent of the myelitis.


Assuntos
Líquido Cefalorraquidiano/virologia , DNA Viral/genética , Genoma Viral , Vírus da Hepatite B/genética , Hepatite B/virologia , Mielite Transversa/virologia , Soro/virologia , Sequência de Bases , DNA Viral/sangue , DNA Viral/líquido cefalorraquidiano , DNA Viral/química , Hepatite B/complicações , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/líquido cefalorraquidiano , Vírus da Hepatite B/isolamento & purificação , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mielite Transversa/complicações , Mutação Puntual , Regiões Promotoras Genéticas , Radiografia , Análise de Sequência de DNA , Medula Espinal/diagnóstico por imagem
8.
Hepatol Res ; 38(4): 415-20, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18021227

RESUMO

Severe hepatitis with an indistinct etiology manifested in a 16-year-old boy who had no particular history. The histological features of the liver and clinical course of the patient were similar to those of patients with autoimmune hepatitis characterized by interface hepatitis and severe lobular inflammation of the liver and recurrent exacerbations of hepatitis. We administered intravenous glycyrrhizin preparation daily or three times a week combined with the oral administration of ursodeoxycholic acid daily throughout the term after the initial onset of disease for the control of disease activity. The normalization of the concentration of alanine aminotransferase in serum was achieved in response to the therapy during the course. The serum concentration of immunoglobulins of the patient gradually decreased from the onset of the disease to an unacceptable level without globulin preparation during the following period of 17 months. Immunological tests revealed impairment of immunoglobulin production bythe B cell population of the patient, which led to the diagnosis of the patient as common variable immunodeficiency (CVID). The patient, with improved liver histology after 27 months from the onset of disease, benefited from the current combination therapy without severe infection through the avoidance of overimmunosuppression. CVID is defined as a heterogeneous syndrome characterized by various degrees of hypogammaglobulinemia without any specific predisposing causes, frequently associated with autoimmunity. Diagnostic criteria and therapeutic options of persistent hepatitis with CVID are to be established, as discussed in the current report.

9.
Hepatol Res ; 37 Suppl 3: S444-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17931200

RESUMO

The heterogeneous functions of cholangiocytes regulate the physiology of the biliary epithelium regarding secretory, proliferative and apoptotic activities. However, due to their technical difficulties for isolation and culture, the pathophysiology of cholangiocytes was poorly understood. Recently, cutting-edge technology, such as the microarray, has given the opportunity for investigating cholangiocytes. We have found the distinct expression profiles of two murine cholangiocytes lines, termed small and large, revealed by microarray analysis. The features of the two cholangiocyte cell lines, categorized partly according to gene ontology, indicate the specific physiological role of each cell line. Namely, large cholangiocytes are characterized as "transport" and "immune/inflammatory responses". In contrast to large, small cholangiocytes are associated with properties of limited physiological functional ability and proliferating/migratingpotential with specific molecules like Eph receptors, comparable to mesenchymal cells. Further analysis using other modern technology, such as proteomics, will provide more information to understand the pathophysiology of cholangiocytes. These novel methods enable us to investigate the key molecules and their mutual relationship. Although the evaluation of some important biological regulatory processes like protein modification requires methodologies other than microarray, microarray technology is anticipated to grow with the development of data-analysis theory for the comprehension of cellular cross-talk in the liver.

10.
World J Gastroenterol ; 13(32): 4394-7, 2007 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-17708618

RESUMO

A 27-year-old Caucasian female with hepatitis C virus (HCV) infection treated with interferon (IFN) who developed severe autoimmune hepatitis (AIH) is described. The infecting viral strain was of genotype Ib and the pre-treatment HCV viral load was at a high level. The patient was treated with pegylated IFN-alpha 2b and ribavirin, and her HCV-RNA became negative at wk 12, but after that she developed fulminant hepatic failure. The patient recovered after steroid pulse therapy consisting of methylprednisolone 1000 mg/d for three days which was administered twice. A needle liver biopsy revealed the typical pathological findings of AIH.


Assuntos
Antivirais/efeitos adversos , Hepatite C/complicações , Hepatite Autoimune/etiologia , Interferon-alfa/efeitos adversos , Falência Hepática Aguda/induzido quimicamente , Ribavirina/uso terapêutico , Adulto , Antivirais/uso terapêutico , Biópsia , Quimioterapia Combinada , Feminino , Hepatite C/tratamento farmacológico , Hepatite Autoimune/diagnóstico , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Fígado/patologia , Falência Hepática Aguda/diagnóstico , Polietilenoglicóis , Proteínas Recombinantes
11.
Hepatogastroenterology ; 54(79): 2113-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18251171

RESUMO

We report the case of a patient having hepatocellular carcinoma with tumor invasion to the inferior vena cava and with multiple pulmonary metastases who was treated with repeated one-shot administration of epirubicin, cisplatin, and mitomycin C by hepatic artery and bronchial artery, which led to complete remission. A 72-year-old woman was diagnosed with infiltrative hepatocellular carcinoma with Vv3, multiple intrahepatic metastases, and multiple pulmonary metastases associated with compensated liver cirrhosis. One-shot infusion of epirubicin, cisplatin, and mitomycin C was performed through proper hepatic artery and bronchial artery for twice at eight weeks of intervals. Pulmonary metastases disappeared and intrahepatic lesions indicated marked shrinkage leaving a scar-like lesion with decreases in tumor markers. After six months and 20 months, tumor markers indicated increasing tendency but no evident recurrence was found by computed tomography or hepatic arteriography. One-shot infusion of the same regimens through proper hepatic artery was performed and tumor markers decreased to normal levels. After 14 months of the last therapy, no evidence of recurrence has been found on image analysis or in tumor markers. This arterial infusion therapy is well tolerated for the patients with compensated liver cirrhosis and might be promising for the effective treatment of advanced hepatocellular carcinoma with pulmonary metastases.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Infusões Intra-Arteriais , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/secundário , Veia Cava Inferior/patologia , Idoso , Artérias Brônquicas , Carcinoma Hepatocelular/diagnóstico por imagem , Feminino , Artéria Hepática , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Invasividade Neoplásica , Indução de Remissão , Retratamento , Tomografia Computadorizada por Raios X
12.
Tohoku J Exp Med ; 210(1): 29-36, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16960342

RESUMO

Hepatitis B virus (HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, remains a major health problem in Asian countries. Recent development of vaccine for prevention is reported to be successful in reducing the size of chronically infected carriers, although the standard medical therapies have not been established up to now. In this report, we encountered a patient with decompensated HBV-related cirrhosis who exhibited the dramatic improvements after antiviral therapy. The patient was a 50-year-old woman. Previous conventional medical treatments were not effective for this patient, thus this patient had been referred to our hospital. However, the administration of lamivudine, a reverse transcriptase inhibitor, for 23 months dramatically improved her liver severity. During this period, no drug resistant mutant HBV emerged, and the serum HBV-DNA level was continuously suppressed. These virological responses were also maintained even after the antiviral therapy was discontinued. Moreover, both hepatitis B surface antigen and e antigen were observed to have disappeared in this patient. The administration of lamivudine to patients with HBV-related cirrhosis, like our present case, should be considered as an initial medical therapeutic option, especially in countries where liver transplantation is not reliably available.


Assuntos
Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/sangue , Hepatite B Crônica/complicações , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/virologia , Cirrose Hepática/etiologia , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Viral
13.
World J Gastroenterol ; 12(29): 4757-60, 2006 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16937453

RESUMO

A 29-year-old nurse with a hepatitis C virus (HCV) infection caused by needle-stick injury was treated with interferon-beta starting about one year after the onset of acute hepatitis. The patient developed acute hepatitis C with symptoms of general fatigues, jaundice, and ascites 4 wk after the needle-stick injury. When these symptoms were presented, the patient was pregnant by artificial insemination. She hoped to continue her pregnancy. After delivery, biochemical liver enzyme returned to normal levels. Nevertheless, HCV RNA was positive and the pathological finding indicated a progression to chronicity. The genotype was 1b with low viral load. Daily intravenous injection of interferon-beta at the dosage of six million units was started and continued for eight weeks. HCV was eradicated without severe adverse effects. In acute hepatitis C, delaying therapy is considered to reduce the efficacy but interferon-beta therapy is one of the useful treatments for hepatitis C infection in chronic phase.


Assuntos
Hepacivirus/patogenicidade , Hepatite C/tratamento farmacológico , Hepatite C/etiologia , Ferimentos Penetrantes Produzidos por Agulha/complicações , Doença Aguda , Adulto , Antivirais/uso terapêutico , Progressão da Doença , Feminino , Hepacivirus/genética , Hepatite C/fisiopatologia , Hepatite C/transmissão , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional , Interferon beta/uso terapêutico , RNA Viral/análise , RNA Viral/genética
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