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E Ono

Publications and source records attributed to E Ono.

At least 55 records · Page 3Linked to original sources

Mapping of transregulatory domains of pseudorabies virus early protein 0 and identification of its dominant-negative mutant.

Pseudorabies virus (PRV) early protein 0 (EP0) is a transactivator containing the RING finger domain. Analysis of transactivating activity of truncated forms of the EP0 molecule consisting of 410 amino acids revealed that amino-terminal region containing the RING finger domain, amino acids 1 to 84, and the region between amino acids 114 to 242 containing acidic amino acid sequences were required for the transactivation. On the other hand, the mutant consisting of amino acids 1 to 113 exhibited a dominant-negative property.

Animals↗

Negative regulation of immediate-early gene expression of pseudorabies virus by interferon-alpha.

Pseudorabies rabies (PrV) replication in Vero cells was suppressed by treatment with human natural interferon-alpha (IFN-alpha). Messenger RNA transcribed from the PrV immediate-early (IE) gene was reduced in the IFN-alpha-treated cells. Transient expression assays showed that transcription from the PrV IE promoter was selectively inhibited in the IFN-alpha-treated cells. Analysis of deletion mutants of the PrV IE promoter sequence suggested that at least one element between the transcription initiation site (+1) and -90 in the PrV IE promoter was concerned with the negative regulation.

Animals↗

Development of immuno-PCR for diagnosis of bovine herpesvirus 1 infection.

A highly sensitive immuno-PCR method specific for the detection of antigens of and antibodies to bovine herpesvirus 1 was established. This assay attained a high sensitivity of up to 10(7.0) times higher than that of enzyme-linked immunosorbent assay (ELISA) or PCR for antigen detection and 10(5.0) times higher than that of ELISA for antibody detection.

Animals↗

Enzymatic activities of several K108 mutants of ribonuclease (RNase) Rh isolated from Rhizopus niveus.

We previously investigated the role of the Lys108 residue of ribonuclease (RNase) Rh from Rhizopus niveus, and suggested that Lys108 probably acts to stabilize the pentacovalent intermediate, and that an Arg residue could replace the role of Lys108. In RNase Le2 from Lentinus edodes, a homologous enzyme of RNase Rh, Lys108 is replaced by Thr. In this paper, the enzymatic properties of a K108T mutant and its analogous enzyme, K108S, were investigated to determine the effect of Thr and its analog, Ser at the 108th position on enzyme activity. The enzymatic properties of these mutant enzymes were compared with those of other mutant enzymes at this position (K108M, K108A, K108L). The results showed that Thr and Ser could replace Lys108 but resulted in only 2-20% of the activity of the native enzyme depending on the substrates used.

Amino Acid Sequence↗

Inhibition of pseudorabies virus replication by a chimeric trans-gene product repressing transcription of the immediate-early gene.

A chimeric gene encoding a fusion protein consisting of the DNA-binding domain of the immediate-early (IE) protein of pseudorabies virus (PRV) and a tail-truncated Vmw65 of herpes simplex virus 1, lacking the transcription activation domain, was constructed. The chimeric gene product inhibited transcription from the PRV IE promoter in a transient expression assay. A HeLa cell line stably transformed with the chimeric gene showed remarkable resistance to PRV infection. In the transformed cells infected with PRV, transcription of the PRV IE gene was repressed, indicating that the resistance of the cells to PRV infection was due to interference with IE gene transcription by the fusion protein.

Base Sequence↗

A tailgut cyst found accompanying rectal cancer: report of a case.

Tailgut cysts are rare congenital lesions. To date, only four cases have been reported in Japan, and the occurrence of a tailgut cyst with rectal cancer has never been documented. We describe here the case of a patient in whom a tailgut cyst in the retrorectal space was associated with rectal cancer. Preoperative computed tomography scans and endorectal ultrasonography failed to identify the lesion as cystic, instead suggesting an involved lymph node. This case emphasizes the necessity for careful diagnosis of masses in the retrorectal space in patients with rectal cancer.

Adenocarcinoma, Mucinous↗

Auxiliary heterotopic partial liver transplantation in pigs with acute liver failure.

Fulminant hepatic failure is usually fatal without liver transplantation; however, orthotopic liver transportation is often difficult to perform due to the high risk of coagulopathy and the development of multiple organ failure. Auxiliary heterotopic partial liver transplantation (APLT), However, has the potential to provide an effective hepatic support system considering that the host liver is left in situ and the surgical procedure is less invasive. In this report, we describe the beneficial effects of performing 60% APLT on the hepatic function and survival of pigs with acute hepatic failure induced by hepatic artery ligation. The pigs were divided into a control group of nine animals (group 1) that had portal vein and hepatic artery ligation with a side-to-side portacaval shunt, and an APLT group of seven animals (group 2) that had portal vein and hepatic artery ligation with APLT. The two left lateral lobes of the donor liver were resected, reducing the liver weight to about 60%, and the graft was placed in the right subhepatic space. No deaths occurred intraoperatively. In group 1, eight pigs died of massive liver necrosis within 48 h and one died between 48 and 72 h (median survival 23 h). In group 2, two pigs died within 72 h due to preservation or anesthetic problems, but five survived for more than 3 days (median survival 13.4 days), with a significant difference between the two groups (P < 0.05). One animal was killed 30 days after APLT and excellent graft function was demonstrated by the synthesis of clotting factors, ammonia detoxification, and glucohomeostasis. Moreover, evidence of hepatic regeneration was found in the transplanted livers.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Mapping of a functional region conferring nuclear localization of pseudorabies virus immediate-early protein.

The immediate-early protein (IE180) of pseudorabies virus (PrV) is localized predominantly in the nuclei of infected cells. To define the nuclear localization signals within IE180, we prepared truncated mutants of IE180 and analyzed their localization in the transfected cells by indirect immunofluorescence. Analysis of mutants truncated from the carboxy-terminal end of the 1460-amino acid polypeptide showed that two regions including a short sequence of basic amino acid residues were associated with the nuclear localization of IE180. To assess whether these regions substantially function as signals for nuclear localization of the IE180 molecule, we then constructed two deletion mutants lacking each region. A mutant lacking amino acids 333 to 575 was detected in the nuclei of the transfected cells, whereas the other mutant lacking amino acids 900 to 950 was detected mainly in the cytoplasm. These results suggest that the region of amino acids 900 to 950 is responsible for nuclear localization of IE180.

Amino Acid Sequence↗

Pseudorabies virus early protein 0 transactivates the viral gene promoters.

Pseudorabies virus (PRV) early protein 0 (EP0) contains the RING finger domain with homology to the immediate-early (IE) protein ICP0 of herpes simplex virus type 1 (HSV-1). EP0 was detected by indirect immunofluorescence in the nuclei of the cells transfected with EP0 expression plasmid as is the case in cells infected with PRV. In transient expression assays, EP0 transactivated the PRV IE, thymidine kinase (TK) and glycoprotein X (gX) promoters, indicating that EP0, like ICP0 of HSV-1, is a transactivating protein.

Animals↗

Translation initiation from non-AUG codons in COS1 cells is mRNA species dependent.

Sendai virus P/C mRNA, human erythrocyte membrane protein 4.1 mRNA and PDGF-B chain mRNA were used to test whether translation initiation from non-AUG codons in COS1 cells was mRNA species dependent. Site-directed mutants of the authentic translation start sites of these mRNAs to alternate start codons showed that while P/C mRNA is capable of initiating translation from non-AUG start sites the other two mRNAs are not. Our study shows that translation initiation from non-AUG codons is mRNA species dependent and suggests that higher order structure of an mRNA determines the non-AUG translation start site.

Animals↗

Mapping of transcriptional regulatory domains of pseudorabies virus immediate-early protein.

The 180 kilodalton immediate-early protein (IE180) of pseudorabies virus functions as a strong transactivator of several different promoters and also as a repressor of its own transcription. To map the functional domains of IE180, we prepared various truncated mutants and analyzed their transcriptional regulatory activities using the chloramphenicol acetyl transferase (CAT) assay. Analysis of mutants truncated from the carboxy-terminal end of the 1,460-amino acid polypeptide showed that a polypeptide possessing amino acids 1 to 1,081 retained significant functions of transactivation and autoregulation potential. On the other hand, removing amino acids 1 to 131 resulted in a complete loss of transactivation potential, indicating that the domain responsible for transactivation is located in the amino-terminal end of IE180. Additional amino-terminal truncation up to amino acid 453 did not affect the autoregulation activity, indicating that the region between amino acids 454 and 1081 has autoregulation potential.

Amino Acid Sequence↗

Mechanism of suppression of cloned human suppressor T cells.

We report the mechanism of suppression of suppressor T cell clone III-1-C5 using helper T cell clone III-1-B6, mitogen responses and rIL-2. Clone III-1-C5 suppressed the mixed lymphocyte reaction (MLR) by secreting alloantigen non-specific, MHC non-restricted suppressor factor(s). Clone III-1-C5 did not suppress mitogen (PHA, Con A, PWM) response nor proliferation by exogeneous rIL-2. Clone III-1-C5 suppressed proliferation by clone III-1-B6, which augments proliferation by direct cell to cell contact with responder cells and not by soluble factors. These results indicated that suppressor T cells exhibit suppressive effects not only by inhibiting IL-2 synthesis but by inhibiting the direct effects of helper T-cells.

Animals↗

Alagille syndrome with a spontaneous appearance of the interlobular bile ducts.

We report a rare case of a 10 year old girl diagnosed as having Alagille syndrome on the basis of a characteristic face, posterior embryotoxon, cholestasis, peripheral pulmonary artery stenosis and the absence of interlobular bile ducts in a liver biopsy at 1.5 years of age. Since 1.5 years old, she had been in good health without medication and the serum biochemical liver function tests indicated no progression of cholestasis. A second liver biopsy at 9.5 years of age showed normal interlobular bile ducts confirmed by anti-keratin staining at each of the five examined portal areas. Alagille syndrome is usually associated with the progressive disappearance of interlobular bile ducts. The findings of interlobular bile ducts in the second liver biopsy were therefore rare and unique to this case.

Alagille Syndrome↗

The cell envelope structure of the lipopolysaccharide-lacking gram-negative bacterium Sphingomonas paucimobilis.

From the cell envelope preparation of Sphingomonas paucimobilis two membrane fractions with different densities were separated by sucrose density gradient ultracentrifugation. The high-density fraction contained several major proteins, phospholipids, and glycosphingolipids, which are the only glycolipids of this lipopolysaccharide-lacking gram-negative bacterium. The low-density fraction showed many minor bands of proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and NADH oxidase activity was localized in this fraction. Combined with morphological data of vesicles formed by these membrane fractions, the high-density and low-density fractions were proposed to be an outer membrane and a cytoplasmic membrane, respectively. The localization of the glycosphingolipid was investigated also by means of immunoelectron microscopic analysis using a glycosphingolipid-specific antibody. The glycosphingolipid was shown to localize at the cell envelope, and the antigenic sugar portion was exposed to the bacterial cell surface. From these results the glycosphingolipid was assumed to have a function similar to that of the lipopolysaccharide of other gram-negative bacteria.

Antibodies, Bacterial↗

The differentiation of entero-endocrine cells of pre- and postnatal rats: light and electron microscopy and immunocytochemistry.

The differentiation of cholecystokinin/gastrin (CCK/GA)-, glucagon (GLU)- and somatostatin (SOM)-positive cells in the pre- and postnatal rat duodenum was investigated with a special emphasis on the relationship to that of the fibromuscular intestinal wall by light and electron microscopy and immunocytochemistry. Between prenatal days 16 and 21, contacts of mesenchymal cells with the epithelium are frequent, and the differentiation of the entero-endocrine cells which occasionally display a secretory function becomes advanced in close proximity to an extensive capillary network in the underlying connective tissue. CCK/GA-positive cells can be detected by immunocytochemistry in the intestinal epithelium at prenatal day 18. Other types of entero-endocrine cells are not detected until prenatal day 19. Quantitative analysis demonstrates that the volume density of CCK/GA-positive cells per 100 microns2 cytoplasmic area increases sharply at postnatal day 5 relative to earlier stages. This may be mainly due to suckling of the neonatal rat.

Animals↗

A neutral sugar is responsible for serovar specificity of the antigenic determinant of Leptospira interrogans serovar canicola.

To provide information on the chemical structures of antigenic determinants of leptospira, glycolipids of Leptospira interrogans serovar canicola strain Hond Utrecht IV (Ut-IV) and its antigenic variant selected in the presence of a serovar-specific monoclonal antibody were compared physicochemically. Gas-liquid chromatography-mass spectrometry analysis revealed that the glycolipid of Ut-IV contained 6 neutral sugar species; rhamnose, mannose, galactose, glucose, and unknown sugars III and IV, in addition to unknown sugars I and II that had been previously reported. On the other hand, the glycolipid of the variant lacked unknown sugar III, suggesting that this sugar is responsible for the serovar-specific antigenic determinant.

Animals↗