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T Umemura

Publications and source records attributed to T Umemura.

At least 19 recordsLinked to original sources
PubMed2007

Anti-Helicobacter pylori seropositivity: influence on severity and treatment response in patients with chronic hepatitis C.

We sought to clarify the incidence and role of Helicobacter pylori (H. pylori) seropositivity in patients with hepatitis C virus (HCV) infection and the effect of coinfection on interferon-alpha and ribavirin therapy. The presence of H. pylori was tested using a commercially available enzyme immunoassay in serum samples from 93 patients with chronic hepatitis C. Clinical features, HCV markers and response of HCV to interferon-alpha and ribavirin were compared between H. pylori-positive and H. pylori-negative patients. Anti-H. pylori antibody was detected in 45 (48%) of the 93 patients, whose median HCV-RNA level (495 vs 760 kIU/mL; P = 0.013) and platelet count (128 vs 158 x 10(3)/microL; P = 0.009) were significantly lower than in patients with HCV infection alone. Anti-H. pylori antibody levels were found to be significantly correlated with fibrosis score (P = 0.0083, r = 0.33) but inversely related to platelet count (P = 0.0037, r = -0.34). The sustained response rate for HCV clearance following interferon-alpha and ribavirin treatment did not differ between patients with and without anti-H. pylori seropositivity. The presence of H. pylori [odds ratio (OR) 8.61; 95% confidence interval (CI) 1.59-46.70] and fibrosis score (OR 30.13; 95% CI 5.44-166.78) were found by multivariate analysis to be associated with the decrease of platelet count during therapy. Coexistent H. pylori infection does not demonstrably influence the clinical course of chronic hepatitis C. A possible connection between H. pylori coinfection and thrombocytopenia was found during the treatment course, suggesting that preemptive eradication of H. pylori may facilitate completion of treatment and increased sustained virological response.

Adult↗
PubMed2006

Pathogenicity of a highly pathogenic avian influenza virus, A/chicken/Yamaguchi/7/04 (H5N1) in different species of birds and mammals.

Outbreaks of highly pathogenic avian influenza (HPAI) have been occurring in domestic poultry in Asia since 1996. In the beginning of 2004, HPAI outbreaks were caused by H5N1 virus in two farms and a group of pet chickens in different areas of Japan. In the present study, the pathogenicity of A/chicken/Yamaguchi/7/04 (H5N1), which had been isolated from a dead chicken during the first outbreak in Japan, was assessed in chickens, quails, budgerigars, ducklings, mice, and miniature pigs by experimental infection. The virus was highly pathogenic to all the birds tested. Mice were susceptible to infection with a low mortality rate and miniature pigs were resistant to infection with the virus.

Animals↗
PubMed2006

Cerebellar hypoplasia associated with an avian leukosis virus inducing fowl glioma.

Fowl glioma-inducing virus (FGV), which belongs to subgroup A of avian leukosis virus (ALV), shows tumorigenicity and pathogenicity, mainly in the nervous system, and causes astrocytoma and perineurioma. Apart from these neoplasms, cerebellar anomaly was found in chickens infected with FGV in ovo. The study reported here describes the morphologic characteristics of the affected cerebellum. Specific-pathogen-free chickens (C/O) were inoculated with FGV through the yolk sac on the 7th day of incubation. The cerebellar anomaly included diffuse depletion of granular cells of the internal granular layer (IGL), remnants of the external granular layer (EGL), and disorganization of the Purkinje cell layer. These cerebellar changes were observed in all birds except one. In the infected embryos, the EGL was thicker and had an irregular arrangement with a thin molecular layer (ML) and IGL, compared with the control. The granular cells were immunohistochemically positive for ALV common antigen. Immunohistochemical analysis for vimentin revealed disarrangement and decreased number of Bergmann's fibers. Use of the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling method and electron microscopy indicated that apoptotic granular cells were frequently observed in the EGL and ML. These results suggested that the cerebellar anomaly was hypoplasia, principally resulting from the apoptosis of granular cells in the EGL and ML caused by FGV infection and that the cell loss induced obstruction of granular cell migration and disarrangement of Bergmann's fibers in the ML.

Animals↗
PubMed2005

Differential susceptibility of equine and mouse brain microvascular endothelial cells to equine herpesvirus 1 infection.

Equine herpesvirus 1 (EHV-1) shows endotheliotropism in the central nervous system (CNS) of infected horses. However, infection of endothelial cells has not been observed in the CNS of infected mice. To explore the basis for this difference in endotheliotropism, we compared the susceptibility of equine brain microvascular endothelial cells (EBMECs) and mouse brain microvascular endothelial cells (MBMECs) to EHV-1 infection. The kinetics of viral growth in EBMECs was typical of a fully productive infection whereas viral infection in MBMECs seemed to be nonproductive. Immunofluorescence microscopy using anti-EHV-1 polyclonal antibody demonstrated viral antigen in infected EBMECs, but not infected MBMECs. EHV-1 immediate early (IE), early (ICP0), and late (gB, gD and gK) transcripts were expressed in infected EBMECs. However, none of these genes was detected in infected MBMECs by reverse transcription-polymerase chain reaction. Electron microscopic examination at the stage of viral entry showed that viral particles were present within uncoated vesicles in the cytoplasm of EBMECs, but absent from those of MBMECs. These results suggest that viral entry is an important determinant of the susceptibility of EBMECs and MBMECs to EHV-1 infection.

Animals↗
PubMed2005

Lack of chemopreventive effects of alpha-eleostearic acid on 7,12-dimethylbenz[a]anthracene (DMBA) and 1,2-dimethylhydrazine (DMH)-induced mammary and colon carcinogenesis in female Sprague-Dawley rats.

alpha-Eleostearic acid is one of the conjugated linolenic acids from tung oil, which is obtained from the seeds of Aleurites fordii. The effects of dietary alpha-eleostearic acid (18:3, n-5) on the post-initiation period of 7,12-dimethylbenz[a]anthracene (DMBA) and 1,2-dimethylhydrazine (DMH)-induced mammary and colon carcinogenesis were examined using female Sprague-Dawley (SD) rats. For initiation, rats were given subcutaneous injections of 40mg/kg body weight (5 times) and 20mg/kg body weight (3 times) of DMH during the age of 6-8 weeks and a single intragastric administration of 50mg/kg body weight of DMBA at 9 weeks. Then, the animals were treated with 0%, 0.01%, 0.1% or 1.0% alpha-eleostearic acid for 34 weeks. Control rats received the basal diet alone or 1.0% alpha-eleostearic acid without prior initiation treatment. All surviving animals were killed at week 37 of the experiment. There were no statistically significant alterations in any of the parameters for either mammary or colon tumors. These results thus indicate that alpha-eleostearic acid does not exert clear modification effects on DMBA and DMH-induced mammary and colon carcinogenesis, at least under the present experimental conditions.

1,2-Dimethylhydrazine↗
PubMed2005

A subchronic toxicity study of dunaliella carotene in F344 rats.

Dunaliella carotene, extracted from dunaliella alga (Dunaliella bardawil or Dunaliella salina), for use as a food-coloring agent, has beta-carotene as its mainly constituent. As there have been no reports of toxicological evaluation, a 90-day subchronic toxicity study was here performed in F344 rats at dose levels of 0 (control), 0.63%, 1.25%, 2.5% and 5% in powdered basal diet. The average daily intakes of dunaliella carotene were 352, 696, 1420 and 2750 mg/kg/day, respectively, for males, and 370, 748, 1444 and 2879 mg/kg/day for females. No mortality or treatment-related clinical signs were observed throughout the experimental period in any of the groups. Body weight gain was slightly but significantly (p < 0.05) reduced from week 5 to the end of the experiment in 2.5% and 5% males. Increased PLT were observed in 1.25% and 5% males, and 2.5% and 5% females. Significant elevations or tendencies for increase in serum T. Cho and Ca were observed in all treated males and females, with clear dose-dependence in males. Organ weight measurement and histopathological observation revealed no toxicological changes. Based on growth suppression, no-observed-adverse-effect-levels (NOAELs) were estimated to be 1.25% (696 mg/kg/day) for males and 5% (2879 mg/kg/day) for females. As increases in serum Ca were observed in the lowest group in both sexes, a no-observed-effect level (NOEL) could not be determined in this study.

Administration, Oral↗
PubMed2005

Neurovirulence of H7N7 influenza A virus: brain stem encephalitis accompanied with aspiration pneumonia in mice.

A mouse-adapted influenza A virus, A/equine/London/1416/73-MA (H7N7) caused viral pneumonia, ganglionitis and encephalitis after intranasal inoculation in mice. Virological and pathological data suggested that this virus spreads to the brain by both hematogenous and transneuronal routes, and produces encephalitic lesions similar to those seen in mice infected with H5 highly pathogenic avian influenza A viruses by intranasal infection. Some mice infected with this strain were affected by aspiration pneumonia, which may be caused by neurogenic dysfunction of the pharyngeal/laryngeal reflex due to brain stem encephalitis.

Animals↗
PubMed2005

Pathogenicity of H5 influenza viruses for ducks.

Four H5N1 highly pathogenic avian influenza (HPAI) viruses and an avirulent reassortant H5N1 virus were tested for their pathogenicity in domestic ducks. A/chicken/Yamaguchi/7/04 (H5N1) (Ck/Yamaguchi/04) isolated from a dead bird during the HPAI outbreak in Japan and A/duck/Yokohama/aq-10/03 (H5N1) (Dk/Yokohama/03) isolated from duck meat at a quarantine inspection for importation from China replicated in multiple organs including the brain of ducks. The ducks infected with Ck/Yamaguchi/04 did not show any clinical signs, while those infected with Dk/Yokohama/03 showed neurological signs. The ducks infected either with A/Hong Kong/483/97 (H5N1) or A/tern/South Africa/61 (H5N3), or with an avirulent H5N1 reassortant, did not show any clinical signs. Virus-specific antibodies were detected in the sera of the ducks infected with each of the five strains tested, indicating that all of the viral strains infected and replicated in the birds. Dk/Yokohama/03 grew in multiple organs more rapidly than did Ck/Yamaguchi/04. Considerable titers of virus were detected in the brain of the ducks infected with Dk/Yokohama/03 and these birds showed neurological signs. The present results demonstrate that the pathogenicity of influenza viruses for ducks does not correlate with that for chickens and that replication of the virus in the brain is critical for ducks to show neurological signs.

Animals↗
PubMed2005

Lack of subchronic toxicity of an aqueous extract of Agaricus blazei Murrill in F344 rats.

Agaricus blazei Murrill, an edible mushroom, is widely used as a functional food due to its possible medicinal effects. Aqueous extracts are also used as food additive to provide an agreeable bitter taste. As a part of its safety assessment, the present 90-day subchronic toxicity study was performed in F344 rats. To establish a no-observed-adverse-effect level (NOAEL), rats were fed powder diet containing A. blazei Murrill aqueous extract at dose levels of 0 (basal diet), 0.63, 1.25, 2.5 and 5% (maximum) for 90 days. During the experiment, there were no remarkable changes in general appearance and no deaths occurred in any experimental group. Although serum blood urea nitrogen was slightly but significantly increased in males of the 2.5 and 5% groups, no related histopathological changes were observed in the kidney, and serum creatinine levels were rather reduced, suggesting the increase of blood urea nitrogen to be of little toxicological significance. Hematology, organ weight measurement and histopathological observation revealed no test compound-related toxicological changes. In conclusion, A. blazei Murrill extract even at 5% in the diet (2654 mg/kgb.w./day for male rats and 2965 mg/kgb.w./day for female rats) did not cause remarkable adverse effects in F344 rats. Thus, the NOAEL was concluded to be 5% in the diet.

Agaricus↗
PubMed2005

Lack of carcinogenicity of D-xylose given in the diet to F344 rats for two years.

The two year carcinogenicity of D-xylose was examined in groups of 50 male and 50 female F344 rats at dietary doses of 0% (control), 2.5% and 5%. The doses were selected on the basis of results from a 13-week subchronic toxicity study. Growth suppression and soft feces were observed in male and female rats of the 5% group. However, no significant differences from the controls were noted with regard to clinical signs, mortality and hematological findings. Decrease in absolute weight and increase in relative weight of the brain in males, and decrease of absolute kidney weight in females were observed in the 5% group, but there were no remarkable histopathological changes. A variety of tumors developed in all groups, including the controls, but all were histologically similar to those known to occur spontaneously in F344 rats, and no statistically significant increase in the incidence of any type of neoplastic lesion was found for either sex in the treated groups. Thus, it was concluded that, under the present experimental conditions, D-xylose is not carcinogenic to F344 rats.

Animals↗
PubMed2005

Nested polymerase chain reaction for detection of the avian leukosis virus causing so-called fowl glioma.

The complete nucleotide sequence of the avian leukosis virus causing so-called fowl glioma has been previously determined. Primers were designed for detection of the fowl glioma-causal virus (FGV) based on the 3' untranslated region of the viral genome. The provirus and viral RNA of FGV were specifically detected in various organs and tissues, including feather pulp, from experimentally infected birds using nested polymerase chain reaction (PCR) and reverse transcription nested PCR. The prevalence of FGV was evaluated in 131 Japanese fowls of a zoological garden in Japan based on the detection of the FGV genome in feather pulp using PCR and the detection of viral antigen in faeces by enzyme-linked immunosorbent assay. FGV proviral DNA was detected in feather pulp of 52 birds (39.7%) by nested PCR. Later, nine dead birds from among the 52 were histologically diagnosed as having fowl glioma and found to have the proviral DNA in the affected brain. These results demonstrated that the PCR-based detection of FGV in feather pulp is useful for epidemiological studies on fowl glioma.

Animals↗
PubMed2005

Age-specific antibody to hepatitis E virus has remained constant during the past 20 years in Japan.

We investigated the presence of antibodies to hepatitis E virus (anti-HEV) and hepatitis A virus (anti-HAV) by enzyme immunoassays in sera from 1015 individuals collected in 1974, 1984 and 1994. Age-specific profiles of anti-HEV remained unchanged with a peak at 40-49 years, while those of anti-HAV started to increase in individuals aged 20-29 years in 1974, 30-39 years in 1984 and 40-49 years in 1994. These results suggest that a silent HEV infection has been taking place in the last 20 years or so in Japan, while HAV infection has been terminated at least since 1974.

Adolescent↗
PubMed2005

SEN virus infection in patients with hepatocellular carcinoma.

Although most cases of hepatocellular carcinoma (HCC) are associated with either the hepatitis B or C viruses (HBV, HCV), about 10-20% of HCCs occur in patients with chronic hepatitis that is aetiologically undefined. The aim of the present study was to determine the prevalence of the transfusion-transmitted SEN virus (SEN-V) in patients with HCC, including those patients who do not otherwise appear to be infected with HBV or HCV. Fragments of SEN-V subtypes D and H were amplified separately by PCR from the sera of 50 patients with HCC (31 from Canada and 19 from Japan) as well as from HCC and adjacent nontumourous liver tissues from eight of the Canadian patients. SEN-V DNA was found in the serum of 10 of 31 (32%) Canadian patients and eight of 19 (42%) Japanese patients [overall, 18 of 50 (36%) HCC patients]. SEN-V DNA was detected in the serum of 10 of 23 (43%) HCC patients with antibody to HCV (anti-HCV), six of 11 (55%) with hepatitis B surface antigen (HBsAg), and two of 16 (12%) without detectable anti-HCV or HBsAg. Twenty-three HCC patients in this study had 'silent HBV,' characterized by the detection of HBV DNA in the absence of HBsAg; eight of these (35%) also had SEN-V infections. SEN-V DNA was detected in HCC patients most typically in those with coexistent HBV or HCV infection. SEN-V was found in only one of seven HCC patients without HBV (without HBsAg or HBV DNA) or HCV and thus does not appear to be an important cause of 'cryptogenic' HCC.

Canada↗
PubMed2005

Multiple perineuriomas in chicken (Gallus gallus domesticus).

Intraneural perineurioma is an extremely rare condition characterized by perineurial cell proliferation within peripheral nerve (PN) sheaths. In the veterinary field, this entity has been reported only in a dog. We examined multiple enlargements of PNs in 11 chickens (Gallus gallus domesticus) (9 Japanese bantams and 2 specific pathogen-free White Leghorn), which were inoculated with an avian leukosis virus (ALV) causing so-called fowl glioma. All chickens clinically exhibited progressive leg paralysis. Lumbosacral plexus, brachial plexus, and/or spinal ganglion were commonly affected, and these nerves contained a diffuse proliferation of spindle cells arranged concentrically in characteristic onion bulb-like structures surrounded by residual axons and myelin sheaths. The spindle cells were immunohistochemically negative for S-100alpha/beta protein. Electron microscopy revealed that these cells were characterized by short bipolar cytoplasmic processes, occasional cytoplasmic pinocytotic vesicles, and discontinuous basal laminae. These features are consistent with those of intraneural perineurioma. Furthermore, the specific sequence of the ALV was detected in the PN lesions of 8/11 (73%) birds by polymerase chain reaction. These results indicate that the multiple intraneural perineuriomas of chicken may be associated with the ALV-A causing fowl glioma.

Animals↗
PubMed2004

Symptoms in relation to chemicals and dampness in newly built dwellings.

OBJECTIVES: As the airtightness of dwellings has recently increased, problems associated with indoor air pollution and dampness have become important environmental health issues. The aim of this study was to clarify whether symptoms in residents living in newly built dwellings were related to chemicals and dampness. METHODS: Symptoms of 317 residents were surveyed by standardized questionnaires, and the concentrations of formaldehyde, acetaldehyde, and 17 volatile organic compounds (VOCs) in their homes were measured. Dampness (condensation on window panes and/or walls, and mold growth) was identified by questionnaires given to the householders or their partners. RESULTS: Some VOCs (toluene, butyl acetate, ethylbenzene, alpha-pinene, p-dichlorobenzene, nonanal, and xylene) were significantly related to the symptoms, and the sum of all VOCs (all identified VOCs) was significantly related to throat and respiratory symptoms [odds ratio (OR) for eye symptoms =2.4; 95% confidence interval (CI) 1.0-5.5], although the concentrations of VOCs were relatively low. As for the dampness index, condensation on window panes and/or walls was related to all symptoms, and mold growth was related to all symptoms except skin, throat and respiratory and general symptoms. As the number of dampness signs increased, the ORs increased for the symptoms except general symptoms (OR for nose symptoms = 4.4, 95% CI 1.6-11.9). CONCLUSION: Both VOCs and dampness were significantly related to symptoms. We should take measures to reduce the concentrations of VOCs, dampness and microbial growth in dwellings.

Acetaldehyde↗
PubMed2004

Decreased expression of equine herpesvirus-1 early and late genes in the placenta of naturally aborted equine fetuses.

Intrauterine infection with equine herpesvirus-1 (EHV-1) has been considered to be the consequence of transplacental transmission of the virus following maternal cell-associated viraemia. In this study the state of EHV-1 gene expression in the placenta of seven naturally aborted equine fetuses was examined. Neither lesions nor viral antigens were detected in the placenta of the fetuses. The amount of infectious virus in the placentas was considerably lower than that in the fetal lungs, which showed pneumonia and typical herpesvirus inclusions. Quantitative dot blot hybridization with probes specific for immediate-early (IE), early (ICP0), and late (gD and gK) genes revealed that the placentas expressed the IE gene at a level comparable with that in the lungs; however, expression of the ICP0, gD and gK genes was significantly weaker in the placentas than in the lungs. In-situ hybridization demonstrated that both IE and gK RNAs were distributed mainly in the cytoplasm of trophoblasts. These results suggest that the low level of early and late gene transcription may be related to the limited production of viral progeny and the lack of immunoreactivity for viral antigen in trophoblasts infected with EHV-1.

Abortion, Veterinary↗
PubMed2004

Nutritional secondary hyperparathyroidism and osteodystrophia fibrosa in a Hodgson's hawk-eagle (Spizaetus nipalensis).

A Hodgson's hawk-eagle (Spizaetus nipalensis) reared by a falconer showed severe weakness with multiple fractures of bone. It had a history of being fed an all-meat diet. Serological examination revealed a hypocalcaemia (72.0 microg/ml), and hypophosphataemia (29.0 microg/ml). Gross and microscopic examinations demonstrated severe osteodystrophia fibrosa (fibrous osteodystrophy) characterized by osteoclastic bone resorption and intertrabecular fibrosis with unmineralized trabecular bone containing a large amount of unmineralized osteoid. There was also hypertrophy and hyperplasia of the parathyroid glands, which is consistent with nutritional secondary hyperparathyroidism.

Animal Feed↗