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Biomedical subjects

H Ogura

Publications and source records attributed to H Ogura.

At least 19 recordsLinked to original sources
PubMed1992

The longevity of the immune response to filamentous hemagglutinin and pertussis toxin in patients with pertussis in a semiclosed community.

Titers of antibodies to the filamentous hemagglutinin (FHA) and pertussis toxin (PT) of Bordetella pertussis were studied in patients from a semiclosed community after an outbreak of the disease in 1985 and in the general population. In convalescent-phase serum obtained after B. pertussis infection in patients in the semiclosed community, high anti-FHA IgG and anti-PT IgG titers were observed; these titers tended to disappear over the next 5 years. On the other hand, among the medical staff, high anti-FHA and anti-PT IgG titers persisted during the same 5-year period. It seems likely that anti-FHA and anti-PT IgG levels reflect the frequency of exposure to the bacteria and that B. pertussis is widespread in the Japanese population. Although the anti-FHA IgG antibody response decreased in patients from the semiclosed community, the cellular immune response was maintained.

Adult↗
PubMed1992

Case report: alternation therapy with antileukemic agents and recombinant human granulocyte colony-stimulating factor for RAEB in transformation.

Under the assumption that in some patients with refractory anemia with excess of blasts (RAEB), the abnormal clones might be less responsive to granulocyte colony-stimulating factor than normal clones, the authors tried alternation therapy with a recombinant form of this factor (rhG-CSF) and antileukemic agents in the treatment of two patients with RAEB in transformation. After repetition of the short-cycled alternation therapy, the hematologic findings of both patients were completely normalized and have remained so without any adverse side effects under the continuation of this therapy for more than 5 months. Judging from our clinical experience, the alternation therapy may be a new efficient therapeutic strategy for RAEB and some types of slowly progressive leukemia.

Adult↗
PubMed1992

Correlation between cytotoxin production and sporulation in Clostridium difficile.

Correlation between cytotoxin production and sporulation was demonstrated when a Clostridium difficile culture was inoculated into fresh broth to give an initial count of less than 10 vegetative cells/ml with no spores. Under these conditions, cytotoxin was produced and released during sporulation. Addition of a sporulation inhibitor (acridine orange, 30 mg/L), resulted in a marked decrease in both sporulation and cytotoxin production, despite there being no change in the number of vegetative cells in the culture. These results indicate that sporulation might be closely related to cytotoxin production.

Acridine Orange↗
PubMed1992

Detection of human papillomavirus type 6f genome in nasal papillomatosis.

Five cases of nasal papillomatosis were studied clinicopathologically and virologically. In a case of recurrent papillomatosis of non-inverted type located on the nasal septum, human papillomavirus (HPV) DNA was detected by dot blot hybridization with an RNA cocktail probe of mucosal HPVs. In Southern blot hybridization, the DNA hybridized with that of HPV types 6 and 11 but not with those of types 16 and 18. Its restriction endonuclease-cleavage patterns corresponded well to those of HPV type 6f. These results suggested that HPV type 6 would also be associated with nasal non-inverted papillomatosis.

Blotting, Southern↗
PubMed1992

[Alveolar bone resorption process in molar tooth region in calcium-deficient rats].

The present study was carried out to investigate the alveolar bone resorption in the molar tooth region in the rats fed a low calcium diet. Male Wistar rats (70-85g in body weight) were either fed a low calcium diet (0.05% Ca, 0.35% P) or a control diet (0.5% Ca, 0.35% P) by using a pair feeding technique. The rats were sacrificed at intervals of 3, 6, 9 and 20 days during the experimental period. Contact microradiograph of the second molar region of the mandible showed that the cancellus bone as well as the endosteal surface of the cortical bone were progressively resorbed soon after the start of low calcium feeding. At day 9, the amount of bone was reduced to about half of the control rats and 80% of the bone was diminished at day 20. In spite of the severe bone resorption, the alveolar bone proper that surrounds the molar sockets and a few cancellus bone were seen remaining and the occlusal function of the molar tooth seemed to be maintained. These results suggest that the alveolar bone quickly responded to the low calcium diet resulting in bone resorption and that the bone in the supporting tissues of the molar tooth seems to be not affected by the calcium deficiency.

Alveolar Bone Loss↗
PubMed1992

Mass trial of hypoallergenic rice (HRS-1) produced by enzymatic digestion in atopic dermatitis with suspected rice allergy. HRS-1 Research Group.

The clinical usefulness of a hypoallergenic rice (HRS-1) which was produced by enzymatic decomposition of the constituent proteins of original rice was evaluated in a multicentre study in 44 subjects with recalcitrant atopic dermatitis (AD), who were suspected of having rice allergy. The subjects were fed for at least 4 weeks with HRS-1 instead of eliminating both regular rice and wheat from their daily diet. The extent of overall skin lesions was expressed by using the AD affected area and severity index (ADASI). A statistically significant decrease in ADASI was observed at the 2nd and the 4th week readings and at the end of the study. A provocation test with regular rice was carried out in 5 of 44 subjects following the HRS-1 therapy. An obvious increase in ADASI was found in all of these 5 cases just after this procedure. On final evaluation, 77% of the patients tested showed 'moderate' to 'remarkable' improvement, and 59% of the patients a 'moderate' to 'remarkable' reduction in use of the steroid ointment concomitantly used for the treatment. Finally, HRS-1 was evaluated as 'useful' or 'very useful' in 69% of the subjects.

Adolescent↗
PubMed1992

Effects of novel uracil analogs on proliferation and differentiation of human myeloid leukemia cells.

Twenty-seven novel nucleobases and nucleosides were synthesized by structural modification of uracil, and their effects on growth and differentiation of human myeloid leukemia HL-60 cells were examined. Some of the compounds inhibited the growth of HL-60 effectively. The nitroblue tetrazolium (NBT)-reducing activities of cells treated with the concentrations of these compounds for 50% inhibition of growth were compared. TI-66 (2,4-dibenzyl-6-fluoro-7,7,8,8-tetramethyl-cis-2,4-diazabicyclo-[4.2.0] octane-3,5-dione) was the most effective inducer of NBT-reducing activity and morphological differentiation of HL-60 cells into cells of the myelomonocytic lineage. TI-66 was also effective for induction of differentiation of another human myelogenous leukemia cell line, ML-1 cells, but not for differentiation of human erythroid leukemia K562 or HEL cells, or monocytic U937 cells. The effect of TI-66 in inducing differentiation of HL-60 cells was additive or more than additive in combination with retinoic acid or vitamin D3. Adenine or hypoxanthine alone induced NBT-reducing activity of the cells, and at suboptimal concentrations these compounds enhanced the effect of TI-66, but the enhanced NBT-reducing activities did not exceed the maximal activity induced by TI-66 alone. Simultaneous treatment of HL-60 cells with hypoxanthine reduced the growth inhibition by TI-66 alone. TI-66 was about 150 times more potent on a molar basis than adenine in inducing differentiation of HL-60 cells. These results suggest that nucleobase analogs such as TI-66 should be useful for differentiation therapy of some types of myelogenous leukemia.

Cell Differentiation↗
PubMed1992

Possible correlation between fusion pattern of BCR/ABL mRNA and clinical response to alpha-interferon in chronic myelogenous leukemia.

Twenty six patients with Philadelphia chromosome (Ph1) positive chronic myelogenous leukemia (CML) treated with IFN-alpha were classified on the basis of the fusion pattern of BCR/ABL chimeric mRNA determined by a reverse-transcriptase-polymerase chain reaction (RT-PCR) method. The relationship between the fusion pattern of BCR/ABL mRNA and the clinical outcome was also analysed. Twelve patients showed M-bcr exon 3/ABL exon 2 (B3/A2) chimeric mRNA and nine had M-bcr exon 2/ABL exon 2 (B2/A2) mRNA. Eleven of the 12 patients with B3/A2 achieved complete hematological response with IFN-alpha therapy, as did three of the nine patients with B2/A2. The mean duration to blastic crisis was significantly longer in the B3/A2 patients (mean 52.4 months) than in the B2/A2 patients (mean 26.2 months) (p less than 0.01). These results suggest that the fusion pattern of BCR/ABL mRNA may affect the therapeutic response to IFN-alpha and clinical outcome in CML patients.

Adolescent↗
PubMed1991

Induction of differentiation of human myeloid leukemia HL-60 cells by novel pyrimidine nucleoside analogs.

New pyrimidine nucleoside analogs (18 compounds) were synthesized and their growth-inhibiting and differentiation-inducing activities on human myeloid leukemia HL-60 cells were examined. Some of the analogs were found to induce nitroblue tetrazolium (NBT) reducing activity in the HL-60 cells. The inducing activities of these compounds were compared at their concentrations for 50% inhibition of cell growth. TI-79 (3-benzyl-5-methyl-3-(beta-D-ribofuranosyl)pyrido[2,3-d]pyrimidine- 2,4(1H,3H)-dione) was a very effective inducer of NBT-reduction and of differentiation of the cells into mature granulocytes. The induction of NBT-reducing activity by TI-79 was inhibited by high concentrations of the natural nucleoside, adenosine. Other differentiation inducers, such as retinoic acid, 1 alpha,25-dihydroxyvitamin D-3 and staurosporin markedly enhanced the induction of differentiation of HL-60 cells by TI-79. Nucleoside analogs such as TI-79 should be useful for differentiation therapy of some types of myelogenous leukemia.

Adenosine↗
PubMed1991

Production of monoclonal antibody to Clostridium difficile toxin A which neutralizes enterotoxicity but not haemagglutination activity.

Nine monoclonal antibodies (mAb) to Clostridium difficile toxin A were produced. The isotype of one mAb (37B5) was IgG2b, kappa, and that of the other eight mAbs was IgM, kappa. Immunoblot analysis after non-denatured PAGE showed that with the exception of one mAb (112G6) all mAbs gave a positive reaction with the 540 kDa band of toxin A. Immunoblot analysis showed that four mAbs (2E15, 3B4, 37B5 and 49C4) gave a positive reaction with the 240 kDa major band of toxin A. In neutralisation tests with these mAbs for enterotoxicity, mouse lethality, haemagglutination activity and cytotoxicity, 37B5 neutralised enterotoxicity in a rabbit ileal loop response test but did not neutralise any other biological activities. None of the other eight mAbs showed any neutralising activities at all.

Animals↗
PubMed1991

Suppression of murine leukemia virus-mediated 3Y1 cell fusion by expression of mouse MHC class I.

Rat 3Y1 fibroblasts transformed by adenovirus type 12 or its E1A gene formed syncytia by cocultivation with Friend murine leukemia virus (MuLV)-producing cells. On the other hand, parental 3Y1 cells and those derivatives induced by other tumor viruses or chemical carcinogen showed no MuLV-mediated syncytium formation [N. Momozaki et al. (1990) Arch. Virol. 115: 123-126]. The expression of major histocompatibility complex (MHC) class I mRNA and antigens was significantly reduced in these Ad12- and E1A-transformed 3Y1 cells. In contrast, other tumor virus-and chemical carcinogen-transformed 3Y1 cells expressed MHC class I almost in normal levels as did parental 3Y1 cells. Furthermore, Ad12-transformed 3Y1 cells which started to express the transfected exogenous MHC class I gene, H-2Ld, showed no more MuLV-mediated 3Y1 cell fusion. These results indicate that the expression of MHC class I on the cell membrane is closely related to the inhibition of 3Y1 cell fusion by MuLV.

Actins↗
PubMed1991

A subtype of human papillomavirus 5 (HPV-5b) and its subgenomic segment amplified in a carcinoma: nucleotide sequences and genomic organizations.

A subtype of human papillomavirus 5 (HPV-5b) is closely associated with carcinomas in the disease epidermodysplasia verruciformis (EV). The complete genome was cloned from virus particles in benign lesions of a patient with EV and sequenced: it was 7779 nucleotides long and consisted of six open reading frames (ORFs) (E6, E7, E1, E2, E4, and E5) in the early region, three ORFs (L2, L3, and L1) in the late region, and a noncoding region, all existing on one DNA strand. The 40% segment of the HPV-5b genome specifically amplified in carcinomas was cloned from a primary carcinoma of the same EV patient and sequenced: it was 3143 nucleotides long and corresponded to a segment of the original HPV-5b genome containing the entire sequences of E6, E7, and the noncoding region and portions of E1 and L1. Compared to the whole genomic DNA, no mutations were detected in this probable malignancy-associated viral subgenomic segment cloned from carcinoma. These results suggest that amplification of the viral segment containing E6, E7, and the noncoding region may play a role in the malignant conversion of HPV-5b-infected benign lesions and that mutations in these genes or regions are not necessarily required.

Base Sequence↗
PubMed1991

Several new approaches to improvement of alpha interferon therapy in chronic myelogenous leukaemia.

Several basic experimental and clinical studies were carried out in an attempt to improve the efficacy of alpha interferon therapy for chronic myelogenous leukaemia (CML). First, the combined use of hydroxyurea (HU) and interferon (500-1000 mg daily) in interferon-resistant cases facilitated maintenance of reduced leucocyte production, or a reduction in the dose of interferon, although suppression of Philadelphia chromosome (Ph1)-positive clones was not observed in most cases. In order to try and decrease the rate of lymphoblastic crisis during the course of interferon therapy, we recently added methotrexate (MTX) (10-15 mg, weekly) to the treatment protocol. Since then, no lymphoblastic crisis has been observed. Second, the in vitro expression of alpha interferon-stimulated gene (ISG) mRNA was shown to be markedly decreased in granulocytes of one representative interferon-resistant case, compared to that in granulocytes of the three interferon-sensitive cases. Interestingly, it was found that the transcriptional activity in this case became almost normal when the blood granulocytes were controlled by the addition of HU. These findings suggest that the in vitro transcriptional assay of ISG mRNA may be clinically useful for predicting alpha interferon efficacy. Third, when genetically manipulated, alpha interferon-producing NIH/3T3 cells were co-transplanted using diffusion chambers into nude mice bearing a CML cell line, KU812, the CML tumour growth was shown to be markedly suppressed. This experimental model for alpha interferon replacement gene therapy suggests some directions for future studies on interferon therapy.

Animals↗
PubMed1991

Immune responses to Bordetella pertussis infection and vaccination.

To assess antibody and cellular immune responses, 156 healthy children were immunized at approximately 18 months of age with acellular diphtheria-tetanus-pertussis vaccine. Changes in antibody responses to filamentous hemagglutinin (FHA) and to pertussis toxin (PT) were similar in pattern, and antibody titers reached values equal to those from patients with convalescent-stage pertussis. The FHA-induced DNA synthesis in peripheral blood mononuclear cells was maximum at 4 weeks after the primary series, and these levels were equal to those of patients with pertussis. High amounts of PT-induced DNA synthesis were observed in both immunized and nonimmunized children; thus, PT seemed to act mainly as a nonspecific mitogen. Almost the same responses to several mitogens that activate different subsets of lymphocytes were observed in young infants compared with older children. Furthermore, young infants who had Bordetella pertussis infection responded by FHA stimulation almost as well as older children.

Age Factors↗
PubMed1991

Acceleration of superoxide production from leukocytes in trauma patients.

Superoxide (O2-) and granulocyte elastase (GE) from neutrophils mediate host defense and tissue injury in inflammation. To determine alterations in leukocyte function after trauma, O2- production and GE secretion from neutrophils were studied in trauma patients (n = 20) and healthy controls (n = 15). The priming effect of tumor necrosis factor (TNF), interleukin-1 alpha (IL-1 alpha), and lipopolysaccharide (LPS) on O2- or GE release also was evaluated. Superoxide production (nmole/10 minutes) was elevated significantly in trauma patients at days 0 (9.5 +/- 4.8), 1 (14.2 +/- 7.3), and 3 (12.2 +/- 5.9) and returned to control levels (4.2 +/- 1.6) by day 7. There was no difference in GE secretion between trauma patients and healthy controls. Incubation of neutrophils with TNF induced release of both O2- and GE. Superoxide production was induced by TNF at concentrations at or greater than 10(-11) mol/L. Granulocyte elastase secretion was induced in a time- and dose-dependent manner by TNF at concentrations between 10(-10) and 10(-7) mol/L. In contrast IL-1 alpha and LPS did not potentiate O2- or GE release. These results suggest that neutrophil O2- production increases acutely in trauma. Tumor necrosis factor may mediate this O2- and GE production by neutrophils involved in the inflammatory response.

Adolescent↗
PubMed1991

Glycosylation of measles virus haemagglutinin protein in infected cells.

Processing of the measles virus haemagglutinin (H) protein was analysed by the pulse-chase method, immunoprecipitation with an anti-H monoclonal antibody and SDS-polyacrylamide gel electrophoresis, combined with the addition of carbonyl cyanide m-chlorophenylhydrazone (CCCP) or monensin (inhibitors of intracellular processing of secretory proteins) to cultures and digestion of the protein with endoglycosidase H or neuraminidase. The apparent Mr of the H protein was increased from 74K to 78K during the chase period. Addition of either CCCP or monensin to the chase medium inhibited the appearance of the 78K H protein, but not the immunoreactivity of the H protein or dimer formation, suggesting that these two events occur in the rough endoplasmic reticulum. The 74K H protein processed in the presence of CCCP was fully sensitive to endoglycosidase H digestion, whereas the 74K H protein processed in the presence of monensin was partially resistant to endoglycosidase H. In experiments using 3H-labelled sugars, [3H]galactose was incorporated into the 74K H protein in the presence of monensin. Neuraminidase treatment increased the electrophoretic mobility of the 78K H protein to 74K. Only the 78K H protein was detected on the surface of untreated cells, and it was resistant to endoglycosidase H digestion. These data suggest that after galactose addition sialic acid is added to the H protein in the trans-Golgi complex and then the mature 78K H protein is transported to the cell surface.

Glycoside Hydrolases↗