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Ryuzo Ueda

Publications and source records attributed to Ryuzo Ueda.

161 records · Page 9Linked to original sources
PubMed2002

Characteristics of hepatitis B virus isolates of genotype G and their phylogenetic differences from the other six genotypes (A through F).

Eight hepatitis B virus (HBV) isolates of genotype G were recovered from patients and sequenced over the entire genome. Six of them had a genomic length of 3,248 bp and two had genomic lengths of 3,239 bp (USG15) and 3,113 bp (USG18) due to deletions. The 10 HBV/G isolates, including the 8 sequenced isolates as well as the original isolate (AF160501) and another isolate (B1-89), had a close sequence homology of 99.3 to 99.8% among themselves (excluding USG18 with a long deletion) but of <88.7% to any of the 68 HBV isolates of the other six genotypes with the full-length sequence known. The eight HBV/G isolates possessed an insertion of 36 bp in the core gene and two stop codons in the precore region, as did the AF160501 and B1-89 isolates. The 10 HBV/G isolates clustered on a branch separate from those bearing the other six genotypes (A through F [A-F]) in the phylogenetic tree constructed from full-length sequences of 78 HBV isolates as well as in those constructed from the core, polymerase, X, and envelope genes. Despite two stop codons in the precore region that prohibited the translation of the HBV e antigen (HBeAg), all of the eight patients with HBV/G infection possessed the HBeAg in serum. By restriction fragment length polymorphism of the surface gene, all of the eight patients were found to be coinfected with HBV of genotype A (HBV/A), which would be responsible for the expression of HBeAg in them. It is worthy of examination to determine how coinfection occurs and whether HBV/G needs HBV/A for replication.

Adult↗
PubMed2002

Liver transplantation-associated de novo hepatitis B virus infection: application of molecular evolutionary analysis.

OBJECTIVE: De novo hepatitis B virus (HBV) infection after liver transplantation has recently been reported to be associated with donors without serum hepatitis B surface antigen (HbsAg) but with hepatitis B core antigen (anti-HBc). We elucidate the source of de novo HBV infection after liver transplantation by molecular evolutionary analysis. METHODS: The serum sample was obtained from a recipient who underwent living related liver transplantation. He was negative for all HBV-related serum markers before the transplantation. The recipient became seropositive for HBsAg at 6 months after transplantation. The liver tissue was obtained from a donor who was seronegative for HBsAg, but positive for anti-HBs and anti-HBc. RESULTS: HBV DNA was detected from the serum and liver tissue in a recipient and donor, respectively. A total of 5 clones each of small-S gene of HBV from the donor and recipient were sequenced. A phylogenetic tree analysis based on small-S gene revealed that all isolates derived from the recipient and donor were clustered together within a close range of evolutionary distances. These results indicated that HBV was transmitted by the liver graft from the donor. CONCLUSIONS: Molecular evolutionary analysis can be adopted for the study of the transmission route of viral infection via organ transplantation.

Adolescent↗
PubMed2002

Increased circulating levels of natriuretic peptides predict future cardiac event in patients with chronic hemodialysis.

BACKGROUND/AIMS: Cardiovascular events are the major determinant of the prognosis in patients with chronic hemodialysis. The present study was designed to investigate whether increased plasma levels of atrial or brain natriuretic peptides (ANP or BNP) predict future cardiac events in such patients. METHODS: Fifty-three patients undergoing chronic hemodialysis without clinical symptoms suggestive of cardiac disorders were enrolled and their blood was sampled for ANP and BNP measurements. Electrocardiograms demonstrated left ventricular hypertrophy in 28 patients but no other abnormal findings. We followed them up for 11.3 +/- 0.2 months. The endpoint was cardiac events. RESULTS: Cardiac events occurred in 13 patients (CE group). Both ANP and BNP levels were higher in CE group than in patients without cardiac events (ANP: 118 +/- 21 vs. 56 +/- 5 pg/ml, BNP: 769 +/- 204 vs. 193 +/- 25 pg/ml, respectively). Receiver operating characteristics curve revealed that the cut-off levels of ANP and BNP were 58 and 390 pg/ml, respectively. Using the Kaplan-Meier method, the incidence of cardiac events was significantly greater in patients with higher levels of ANP (50.0 vs. 0.0%) or BNP (72.7 vs. 11.9%) than in those with lower levels of the peptides. CONCLUSIONS: Elevated levels of ANP or BNP indicate an increased risk of cardiac events and these peptides are clinically useful to predict cardiac events in patients with hemodialysis.

Aged↗
PubMed2002

A study on intraalveolar exudates in acute mycoplasma pneumoniae infection.

Pathologic features of Mycoplasma pneumoniae infection (M. pneumonia) are generally non-specific, and the literature regarding the pathologic features of M. pneumonia with intraalveolar exudates is limited. Clinical and histopathological studies were performed in 3 patients with M. pneumonia which did not respond to erythromycin and minocycline, but all rapidly recovered after corticosteroid therapy. In pathologic findings, we observed intraalveolar exudates and focal organization in M. pneumonia, and its intraalveolar lesions were compared between M. pneumonia and bronchiolitis obliterans organizing pneumonia containing fibrin (BOOP). Immunohistochemical studies were performed using the streptavidin biotin peroxidase complex method with anti-alpha-smooth muscle actin antibody and anti-pancytokeratin AE1/AE3 antibody. In pathologic findings, more fibrin deposits in intaalveolar lesions were observed in M. pneumonia than in BOOP. In intaalveolar lesions of M. pneumonia, a larger amount of nuclear debris, more neutrophils, and more erythrocytes were noted. Myofibroblasts were observed in the organization of BOOP, while in the intaalveolar lesions of M. pneumonia, myofibroblasts were not observed. These results suggest that M. pneumonia with intraalveolar exudates responds well to corticosteroid and its intraalveolar lesions apparently differed from those in BOOP.

Acute Disease↗
PubMed2002

A limited association of OGG1 Ser326Cys polymorphism for adenocarcinoma of the lung.

The 8-oxoguanine DNA glycosylase (OGG1) repairs DNA by removing 8-hydroxyguanine, a highly mutagenic oxidative DNA adduct. Recently, the gene for OGG1 was cloned and several polymorphisms have been reported. Because environmental carcinogens produce 8-hydroxyguanine residues that potentially cause oncogenic mutations by mismatching to this modified base, the capacity to repair these lesions can be involved in cancer susceptibility. This study investigated the association between OGG1 Ser326Cys polymorphism and risk of the lung adenocarcinoma for Japanese by a prevalent case-control study in Japan. The subjects comprised 138 cases and 241 non-cancer outpatients as controls. OGG1 gene polymorphism was genotyped by a PCR-CTPP (polymerase chain reaction with confronting two-pair primers) method. The distribution of OGG1 Ser326Cys genotype among controls (Ser/Ser, 28.3%; Ser/Cys, 49.2%; and Cys/Cys, 22.5%) was not different from that among cases (Ser/Ser, 29.0%; Ser/Cys, 51.4%; and Cys/Cys, 24.0%). The sex-age adjusted odds ratio (OR) was 1.06 with 95% confidence interval (CI) 0.64-1.76 for Ser/Cys genotype and 0.81 with 0.44-1.52 for Cys/Cys genotype. The ORs according to the interval between diagnosis and study enrollment were also examined because the polymorphism was a potential prognostic factor of lung cancer. The ORs of Ser/Cys and Cys/Cys genotypes in the cases less than 3 years after diagnosis were higher than overall ORs; 1.86 (95%CI, 0.91-3.77), and 1.46 (0.64-3.35), respectively. The OR for smoking was not statistically different among genotype, though the sample size was too small to detect even a moderate interaction. This study supported the first study by Sugimura et al (Cancer Epidemiol Biomarkers Prev, 1999; 8: 669-674), that the association of OGG1 Ser326Cys polymorphism was limited for the risk of lung adenocarcinoma.

Adenocarcinoma↗
PubMed2002

[Clinical significance of soluble interleukin-2 receptor as a putative systemic nutritional index in the elderly].

The clinical significance of a slight increase of serum soluble interleukin-2 receptor (sIL2R) concentration in the stable elderly was investigated. Thirty-five residents of nursing homes with physical impairment as a sequel to cerebral infarctions, without any inflammatory condition, anodyne or immunological treatment, were divided into two groups: 24 without overt or suspected malignancy (NC) and 11 with a history of malignancy (CA). Serological screening with measurement of sIL2 R concentrations was performed and numbers of lymphocytes with CD4, CD8 markers were determined. The NC group was divided into controls (n = 15, sIL2R < = 883 U/mL) and subjects demonstrating elevation (n = 9, NH), as in a previous study. Differences were found in serum concentrations of albumin, blood urea nitrogen, total cholesterol concentration, Pettigrew's prognostic nutritional index (PNI), as well as the ADL score, but not age or sex between NH and controls. Factor analysis in NC revealed serum creatinine and blood urea nitrogen concentrations to correlate positively, and serum albumin, total cholesterol concentrations, ADL score, PNI to correlate negatively to sIL2R. Differences were found in sIL2R, albumin, total protein, total cholesterol, beta-lipoprotein, PNI between CA and controls, but correlations were not found in CA. Survival rate of controls over twenty-four months was better than that of NH, but not of CA. Our results suggest that a slight increase of concentration of sIL2R is related to subclinical systemic deterioration, especially with regard to nutrition, with a plausible connection to prognosis of the stable elderly without malignancy.

Activities of Daily Living↗
PubMed2002

[A case of multiple myeloma with infiltration into skeletal muscle after injections of a granulocyte-colony stimulating-factor].

Multiple myelomas often occur in elderly people with complications due to aging. A 54-year-old man was first admitted with cerebral infarction, and multiple myeloma (IgG kappa, stage IIIA) occurred in November 1989 that was followed by partial remission after chemotherapy. The karyotype of the bone marrow cells was 46, XY, and no p53 gene mutations were detected by polymerase chain reaction and single-strand conformation polymorphism analysis. Chemotherapy (melphalan 10 mg, vindesine 3 mg, ranimustine 150 mg, prednisolone 60 mg for 4 days) was performed in February 1999 because of aggravation of the myeloma. After daily subcutaneous injection of 50 micrograms of nartograstim for six days to treat neutropenia, soft tissues around the right eye were swelled gradually without redness, accompanied by elevation of the serum creatine-kinase concentration. The swelling disappeared, and the enzyme level normalized after discontinuation of nartograstim. In July, on the sixth day of daily subcutaneous injection of 75 micrograms of filgrastim after the same chemotherapy, similar swelling of the soft tissues around the left eye became evident, and again this proved reversible. In July 2000, 40 mg of dexamethasone was infused, and after 5-day subcutaneous-injection of 75 micrograms of filgrastim daily, the right subclavicular soft tissue became swollen. He died of myocardial infarction, and autopsy revealed infiltration of myeloma cells into the right subclavicular muscle and bone marrow packed with myeloma cells. This case suggests that myeloma cells can proliferate and infiltrate into soft tissues on exposure to granulocyte-colony stimulating factors.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

[Tumor markers in malignant lymphoma].

The clinical usefulness of tumor markers for malignant lymphoma is thought to be in monitoring the therapeutic effect and as a prognostic factor before treatment. The former include specific biological marker such as soluble interleukin-2 receptor measured by ELISA. The latter are cellular prognostic markers detected by immunohistological and flow cytometric analysis. The cyclin D1 over-expression of mantle cell lymphoma in diffuse large B-cell lymphoma, which should be recommended for myeloablative therapy, is a significantly poor prognostic risk factor.

Biomarkers, Tumor↗
PubMed2002

[Successful use of immunosuppressive agents for the treatment of progressive rheumatoid interstitial lung disease: a case report].

Interstitial pneumonia (IP) is sometimes a fatal complication of rheumatoid arthritis (RA). We describe a patient with progressive rheumatoid interstitial pneumonia, who responded to intravenous intermittent cyclophosphamide (IV-CY) and cyclosporine (CsA). A 62-year-old man with rheumatoid arthritis was admitted to this hospital because of dyspnea. Examinations on admission revealed that he had active RA with vasculitis and IP Initially, he responded to high-dose corticosteroid therapy. A lung biopsy performed after initial corticosteroid therapy revealed diffuse interstitial pneumonia with marked infiltrations of macrophages into the air spaces. On corticosteroid therapy with prednisolone 30 mg/day, the IP became exacerbated and was refractory to the current high-dose steroid treatment. He responded to intravenous cyclophosphamide, but his IP remained unstable. After CsA treatment was started, a clinical remission was obtained. In this case, CsA was the most effective agent tried. Clinical and pathological considerations led us to speculate that activated alveolar macrophages played a crucial role in the pathogenesis of steroid-resistant IP in this patient, and that the clinical remission induced by CsA may have been due to its inhibitory effect on alveolar macrophages.

Arthritis, Rheumatoid↗
PubMed2002

[Adenocarcinoma of the lung with skeletal muscle metastasis, resulting in death due to myocardial metastasis: a case report].

A 57-year-old man was admitted to the hospital because of multiple subcutaneous masses with pain, mild dyspnea, and bloody sputum. He had been asymptomatic until one month earlier, when he began to have a dry cough and myalgia of the right forearm. A chest radiograph showed cardiomegaly. Whole-body computed tomographic scan, cytologic examination of the sputum, and histological examination of a subcutaneous nodule on the scalp resulted in the diagnosis of lung cancer with multiple organ metastases, including those to skeletal muscle and myocardium. Despite chemotherapy, he died suddenly on the 45th hospital day. Autopsy revealed that about half of the myocardium had been replaced by metastatic tumors, so we speculated that he died from heart failure due to cardiac muscle metastasis.

Adenocarcinoma↗
PubMed2002

[Recurrence of thymoma accompanied with hypogammaglobulinemia 20 years after surgery: a case report].

We reported a case of recurrence of localized thymoma accompanied with hypogammaglobulinemia (Good's syndrome) 20 years after surgery. A 74-year-old man was admitted to this hospital because of mediastinal tumor and chronic pulmonary infection. He had been thymectomised at the age of 55 because of spindle cell thymoma. After that, he had been asymptomatic until January 1997, when he began to have a recurrent productive cough, and low-grade fever. Laboratory findings revealed hypogammaglobulinemia. Percutaneous needle biopsy of the mediastinal tumor revealed spindle cell thymoma. Therefore, hypogammaglobulinemia with thymoma (Good's syndrome) accompanied with a chronic lower respiratory tract infection was diagnosed. Immunologic studies revealed a marked decrease of CD 20 positive cells and decreased lymphocyte activation under the stimuli of phytohemagglutinin and concanavalin A. The thymoma was resected in Dec 1997, but the serum immunoglobulin showed no increase at al.

Agammaglobulinemia↗
PubMed2002

[Monoclonal antibody for cancer treatment].

Antibodies have for many decades been viewed as ideal molecules for cancer therapy. Although promising from the start, it has taken much of more than two decades to reach the level of clinical application. Genetic engineering of antibodies; that is novel technologies for chimeric or humanizing monoclonal antibodies, has greatly advanced their utility in molecular targeting therapies, and in the past four years some therapeutic monoclonal antibodies for hematologic malignancies and solid tumors, such as Rituximab for B-cell lymphoma and Trastuzumab for metastatic breast cancer, have provided sufficient efficacy and safety to support regulatory approval from the U.S. Food and Drug Administration. They were subsequently approved by the Japanese Ministry of Health, Labour and Welfare in 2001. Many molecular biological and immunological studies have revealed the targeting properties of the host immune system and the biological mechanism of cancer cells for a more specific anticancer effect. Many clinical trials of monoclonal antibodies as a single agent, or in combination protocol with current standard chemotherapy or immunoconjugates have shown promise in the treatment of specific diseases. Furthermore, novel antibody designs and improved understanding of the mode of action of current antibodies lend great hope to the future of this therapeutic approach. The accumulating results from many basic, clinical and translational studies may lead to more individualized therapeutic strategies using these agent directed at specific genetic and immunologic targets.

Antibodies, Monoclonal↗
PubMed2002

[A patient with mediastinal liposarcoma showing dedifferentiation].

A 70-year-old man visited our hospital with fever and general malaise. Chest CT scanning showed a large tumor shadow in the anterior mediastinum. The tumor was resected. It consisted of a portion rich in fat on the anterior mediastinal side and a solid portion on the left thoracic cavity side. Pathological examination demonstrated liposarcoma (myxoid type). The solid portion was considered to have resulted from dedifferentiation of the cystic portion. Mediastinal liposarcoma accounts for less than 1% of all mediastinal tumors. To our knowledge, there have been no previous reports of patients with myxoid-type mediastinal liposarcoma showing dedifferentiation.

Aged↗
PubMed2001

A novel variant genotype C of hepatitis B virus identified in isolates from Australian Aborigines: complete genome sequence and phylogenetic relatedness.

There have been no reports of DNA sequences of hepatitis B virus (HBV) strains from Australian Aborigines, although the hepatitis B surface antigen (HBsAg) was discovered among them. To investigate the characteristics of DNA sequences of HBV strains from Australian Aborigines, the complete nucleotide sequences of HBV strains were determined and subjected to molecular evolutionary analysis. Serum samples positive for HBsAg were collected from five Australian Aborigines. Phylogenetic analysis of the five complete nucleotide sequences compared with DNA sequences of 54 global HBV isolates from international databases revealed that three of the five were classified into genotype D and were most closely related in terms of evolutionary distance to a strain isolated from a healthy blood donor in Papua New Guinea. Two of the five were classified into a novel variant genotype C, which has not been reported previously, and were closely related to a strain isolated from Polynesians, particularly in the X and Core genes. These two strains of variant genotype C differed from known genotype C strains by 5.9-7.4% over the complete nucleotide sequence and 4.0-5.6% in the small-S gene, and had residues Arg(122), Thr(127) and Lys(160), characteristic of serotype ayw3, which have not been reported previously in genotype C. In conclusion, this is the first report of the characteristics of complete nucleotide sequences of HBV from Australian Aborigines. These results contribute to the investigation of the worldwide spread of HBV, the relationship between serotype and genotype and the ancient common origin of Australian Aborigines.

Amino Acid Sequence↗
PubMedDate not supplied

Histopathological investigation of salivary glands in the asymptomatic elderly.

The significance of labial gland biopsies (LGBs) in the diagnosis of Sjögren's syndrome (SS) in the elderly has been a controversial subject since it is complicated by age-related histopathological changes. In an attempt to clarify the appropriateness of LGBs in present diagnosis criteria, we evaluated the specificity of LGBs using autopsied tissues. This was done by taking labial, sublingual and submandibular salivary glands from 53 autopsy subjects (24 males and 29 females) with an average age of 84 years, and testing them histopathologically with reference to a previously reported grading system. None had any sicca symptoms (oral dryness or dry eye). In subjects up to 75 years old, acinar atrophy was more frequent in labial glands than in the two major salivary glands (P=0.0098 for sublingual and P=0.0009 for submandibular glands). Also, while there were significant differences in frequency of such atrophy between the sublingual and submandibular salivary glands of subjects younger and older than 75, the labial glands showed no such variation. Taking grade 3 (focus score of 1) as the diagnosis criterion, two subjects were determined to have SS in which case the specificity was 95%. Using contemporaneous serological test results for anti-SSA/Ro antibodies as a diagnostic criterion raised specificity to 98%. For both major and minor glands, these appeared to be no relationship between degree of lymphocytic infiltration and age. Our results thus suggest that it is appropriate to adopt a focus score of 1 as a diagnostic criterion for SS in the elderly, and that serological test results can improve specificity.

Aged↗
PubMedDate not supplied

Usefulness of Tc-99m methoxyisobutylisonitrile scintigraphy for evaluating congestive heart failure.

BACKGROUND: Evidence is accumulating that technetium 99m methoxyisobutylisonitrile (MIBI) is not retained in the impaired myocardium. The purpose of this study was to determine whether the severity of congestive heart failure (CHF) can be evaluated by use of the washout rate (WR) of MIBI. METHODS AND RESULTS: Seventeen patients with CHF and ten healthy volunteers were enrolled in this study. MIBI and iodine 123 metaiodobenzylguanidine (MIBG) scintigraphy techniques were performed, and the WR was calculated. The blood was also sampled for the measurement of levels of brain natriuretic peptide, which is a powerful predictor of the severity of CHF. The WR of MIBI was higher in CHF patients (31.2%+/-6.3%) than in healthy volunteers (25.2%+/-4.7%) (P<.05). There were positive correlations between the WR of MIBI and brain natriuretic peptide levels (r=0.723, P<.0001) and a negative correlation between the WR of MIBI and the left ventricular ejection fraction (r=-0.545, P<.01). The WR of MIBI was correlated with that of MIBG (r=0.603, P<.01). CONCLUSIONS: MIBI scintigraphy is useful in evaluating the severity of congestive heart failure.

3-Iodobenzylguanidine↗