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Biomedical subjects

T Hirao

Publications and source records attributed to T Hirao.

At least 19 recordsLinked to original sources
PubMed1991

Exercise-induced urinary excretion of leukotriene E4 in children with atopic asthma.

Urinary levels of leukotriene (LT) E4, a stable end-product of LTC4 and LTD4, were measured before and after exercise in 10 children with severe asthma and seven children with moderate asthma using HPLC and RIA to clarify the relationship of LT to the severity of asthma and to the degree of bronchospasm in exercise-induced asthma. The urinary LTE4 level significantly increased after exercise in the severe asthma group, but not in the moderate asthma group (14.3 +/- 14.5 to 24.3 +/- 20.6 versus 19.6 +/- 12.3 to 17.6 +/- 10.8 ng/mmol creatinine, p less than 0.05). The urinary LTE4 level increased in 10 patients (eight with severe asthma), and it decreased in seven patients (five with moderate asthma). A significant difference in the degree of bronchospasm after exercise (as shown by the maximal % fall in the peak expiratory flow rate), was seen when patients with increased urinary LTE4 excretion were compared with those with decreased excretion (60.4 +/- 17.3 versus 24.1 +/- 14.3%, p less than 0.01). Our findings suggest that exercise-induced asthma, or at least a subtype of exercise-induced asthma, may partly develop through the release of LTC4.

Asthma, Exercise-Induced↗
PubMed1991

Dermatophagoides pteronyssinus specific IgM antibody and its complement activation in children with bronchial asthma.

Western blotting analysis and ELISA were used to examine Dp specific IgM abs in the sera and sputa of bronchial asthmatic and non-atopic children. With Western blotting Dp specific IgM abs were detected binding diffusely to high molecular weight (greater than 65 kD) components of Dp extracts and from the intensities of the staining of the sera the asthmatic children were divided into two groups: an intensive staining and a faint staining group. The non-atopic children showed still fainter staining than the latter group. ELISA titers of Dp specific IgM abs in the intensive staining group were significantly higher than in the faint staining group and the non-atopic children (p less than 0.01). Dp specific IgM abs in sputa were also detected more intensively in asthma than in non-atopy by Western blotting. The hemolytic complement activities of the fresh sera were consumed when they were incubated with Dp extracts at 37 degrees C. The degree of consumption was significantly higher in the intensive staining group than in the faint staining group and the non-atopic children (p less than 0.05). High molecular weight fractions of Dp extracts were responsible for this complement inactivation. From these results we suspected that Dp specific IgM abs might react with high molecular weight components of Dp to induce complement activation by the classical pathway and might cause chronic inflammatory changes in the respiratory mucosa. This chronic inflammation might emphasize IgE mediated asthmatic reactions to cause late phase reactions or chronic asthma.

Animals↗
PubMed1990

[Relationship between human papillomavirus and oncogenes (c-myc, N-myc) amplification in human cervical cancers].

The human papillomavirus detection and oncogenes amplifications were studied on DNAs from fifteen cervical cancers. We detected HPV16 and HPV18 using Southern blot hybridization and polymerase chain reaction (PCR) technique. The positive subjects of HPVs were eight cases (53%) observed by Southern blot hybridization and fourteen cases (93%) by PCR technique. The gene amplifications of oncogenes (c-myc and N-myc) were analysed by slot-blot method and were observed in c-myc but not in N-myc. The "LARGE" gene amplification (more than five fold) in c-myc was observed in one case (7%) and the "SMALL" gene amplifications (less than five fold) were observed in six cases (40%) in human cervical cancers. Although one of five cases (20%) with HPV16 was present c-myc gene amplification, all of three cases (100%) with HPV18 were found c-myc gene amplifications. In two out of three cases obtained more than three fold c-myc gene amplifications, HPV were not detectable. It is suggested that the negative correlation between gene amplification and numbers of HPV copies exist in advanced cervical cancers.

Adult↗
PubMed1990

Solvent effects on the cooperative order-disorder transition of aqueous solutions of schizophyllan, a triple-helical polysaccharide.

A triple helical polysaccharide schizophyllan in aqueous solution exhibited a highly cooperative transition between ordered and disordered states associated with the conformation of its side chains and nearby water molecules. The transition was followed by optical rotation and calorimetry using water containing additives such as NaOH and DMSO as solvents. The ordered state was stabilized or destabilized depending on the kind and amount of the additive employed; in particular, the addition of DMSO had a remarkable stabilizing effect. This effect was analyzed by means of a statistical mechanical theory of linear cooperative transitions, where DMSO was assumed to interact favorably with the ordered side chains. A small amount of NaOH in a solvent mixture stabilized the ordered state and made the transition curve very gradual. No molecular mechanism was elucidated to account for the role of NaOH.

Calorimetry↗
PubMed1990

Bronchoscopic and cytopathological findings of tracheobronchial involvement in esophageal carcinoma.

To evaluate the usefulness of bronchoscopic and cytopathologic examinations for tracheobronchial involvement of esophageal carcinoma, we reviewed 14 cases of esophageal carcinoma suspected of tracheobronchial invasion. Two cases underwent bronchoscopy for postoperative respiratory symptoms, and both revealed endotracheal tumor growth and proved positive at brush cytology and biopsy. Among nine cases submitted to preoperative examination, bronchoscopy showed only protrusion in four cases, and redness with mucosal protrusion in five cases. Two of the latter evidenced cancer cells on brushing specimen, and their prognosis was poor. The remaining three cases underwent bronchoscopy for preoperative severe respiratory symptoms. Tumor growth was noted in two of them, and cytology or biopsy was positive. We conclude that bronchoscopy for tracheobronchial involvement of esophageal carcinoma plays a major role in the diagnosis of extra-esophageal extension. Because of the anatomical situation, biopsy is sometimes difficult. Brush cytology is important in the case of mucosal protrusion and redness.

Aged↗
PubMed1989

Passive air-pouch anaphylaxis in rats. I. Induction of anaphylaxis.

Induction of an experimental passive anaphylaxis of the air-pouch type, passive air-pouch anaphylaxis, was carried out in an attempt to induce a reproducible anaphylaxis model suitable for quantitative studies. Rats were injected subcutaneously with 10 ml of air into the dorsal skin to make an air-pouch and with 2 ml of antiserum at an appropriate dilution for passive sensitization, and then 5 ml of air was removed. The challenge with 5 ml of antigen solution into the air-pouch 48 h later provoked mast cell degranulation and increased vascular permeability induced by released histamine. Treatment with monovalent hapten prior to the antigen challenge almost completely inhibited histamine release and plasma exudation to levels similar to those in the nonsensitized group. In this model, mast cell-dependent late-phase allergic reaction, such as leukocyte migration or the increase of plasma exudation following mast cell degeneration, was not observed.

Air↗
PubMed1989

Passive air-pouch anaphylaxis in rats. II. Pharmacological characterization.

The effects of some antiallergic agents on passive air-pouch anaphylaxis (PAPA) in the dorsal skin of rats were investigated by measuring plasma exudation and histamine content in the pouch fluid. Antiallergic agents, disodium cromoglycate (DSCG), tranilast and ketotifen, dose dependently inhibited both plasma exudation and histamine release, except that ketotifen showed a dose-unrelated inhibition of histamine release. An antihistamine, pyrilamine, suppressed plasma exudation without affecting histamine release. A cyclooxygenase inhibitor, indomethacin, and a 5-lipoxygenase inhibitor, nordihydroguaiaretic acid (NDGA), showed no significant effect. A slow-reacting substance of anaphylaxis antagonist, FPL55712, exerted no effect at 0.3 and 3.0 micrograms/ml, but at 50 micrograms/ml it suppressed not only plasma exudation but also histamine release. Dexamethasone suppressed plasma exudation dose dependently without inhibiting histamine release significantly. A beta-stimulant, isoproterenol, and prostaglandin E2 also exerted significant inhibitory effects on plasma exudation but not on histamine release at 1 mg/ml. Theophylline inhibited both plasma exudation and histamine release. These observations indicate that PAPA is useful for studying antiallergic agents.

Adult↗
PubMed1986

Inherited deficiency of the seventh component of complement associated with meningococcal meningitis: lack of serum bactericidal activity against Neisseria meningitidis in a girl with C7 deficiency and HLA studies of a C7-deficient Japanese family.

An 8-year-old girl with meningococcal meningitis lacked serum complement activity. The seventh component of complement (C7) could not be detected in her serum by either functional or immunochemical analysis. The levels of the other components were within the normal range. Her serum complement activity was restored by the addition of purified C7. Her fresh serum showed a total absence of bactericidal activity against Neisseria meningitidis, group Y, but her serum bactericidal activity was restored by the addition of purified C7. The restoration of her serum bactericidal activity was completely inhibited in the presence of Mg2+ EGTA. These findings suggest that restoration of the bactericidal activity of her serum against N. meningitidis might be mediated by the specific antibody against N. meningitidis and the reconstituted complement system in her serum. Heterozygous deficiency of C7 was found in 10 of her family members. Genetic studies showed that the mode of inheritance might be an autosomal codominant trait. No genetic linkage between deficiency of C7 and the HLA system was found.

Blood Bactericidal Activity↗
PubMed1985

Reconstitution of cell-mediated immunity in severe combined immunodeficiency following fetal liver transplantation.

A male infant X-linked, adenosine deaminase-positive severe combined immunodeficiency underwent partial immunological reconstitution by fetal liver transplantation at twenty months of age. Reconstitution of T lymphocytes was observed from sixteen weeks after transplantation, in the increase of T lymphocytes, positive delayed-type skin reaction and in vitro responsiveness to mitogens and allogeneic cells, sequentially. Chimerism was defined by chromosomal analysis and HLA typing, in which one haplotype seemed to be shared between the donor and the host by chance. However, defective immunoglobulin production has not yet been corrected. The assay on T-B lymphocyte interaction in vitro suggested that the failure might be attributed to an intrinsic defect of B lymphocytes, which were cells of donor origin after transplantation. Three years following transplantation, the patient is free of severe infections, although he requires regular injections of gamma globulin.

B-Lymphocytes↗
PubMed1984

Stature, sitting height and relative sitting height of female northern Kyushuites.

Stature, sitting height and relative sitting height (a ratio of sitting height to stature) of 318 high school girls of 17 years of age in Kitakyushu City were studied. They consisted of groups over a three-year period; 1973, 1980 and 1984. There are statistically no significant changes in the stature, in the sitting height, and in the relative sitting height among these three groups. The relative sitting height of these three groups is about 54%, which is about the same as among the Chinese, Eskimos, American-Indians and the Hokkaido-Ainu.

Adolescent↗
PubMed1984

Purification and characterization of cathepsin B from monkey skeletal muscle.

Cathepsin B was purified about 11,000-fold from monkey skeletal muscle by ammonium sulfate fractionation and sequential column chromatographies monitored by assaying of Z-Phe-Arg-MCA hydrolase activity. The purified enzyme gave a single protein band on SDS-polyacrylamide gel electrophoresis, and its molecular weight was estimated to be 24,000 by gel filtration. It had a pH optimum of 6.5, required a thiol reducing agent for activation, and was inhibited by various thiol protease inhibitors. These properties were similar to those reported for cathepsins B from other sources. Although the enzyme scarcely hydrolyzed ordinary proteins, such as casein, hemoglobin, and bovine serum albumin, it degraded myosin and actin among various myofibrillar proteins. These results strongly suggested that skeletal muscle cathepsin B may participate in the degradation of muscle proteins in vivo. In addition, cathepsin B was shown to hydrolyze various neuropeptides such as Leu-enkephalin, beta-neoendorphin, alpha-neoendorphin, dynorphin(1-13), and substance P. It appeared to act on these peptides mainly as a dipeptidyl carboxypeptidase, although not so rigorously, presumably due to its endopeptidase activity.

Animals↗
PubMed1984

Purification and characterization of a calcium-activated neutral protease from monkey brain and its action on neuropeptides.

A calcium-activated neutral protease was purified from Japanese monkey brain by ammonium sulfate fractionation and sequential column chromatographies monitored by assay of caseinolytic activity. The purified enzyme gave a single protein band on non-denaturing polyacrylamide gel electrophoresis, and consisted of two subunits with molecular weights of 74,000 and 20,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme required millimolar order calcium ions for activation, and was optimally active at pH 7.5-8.0. Upon incubation with various neuropeptides as substrates, the enzyme preferentially cleaved the peptide bonds with Arg, Lys, or Tyr at the P1 position and an amino acid residue with a bulky aliphatic side chain, such as Leu, Val, or Ile, at the P2 position. The hydrolytic activity toward neuropeptides as well as casein was strongly inhibited by various thiol protease inhibitors. These results suggested that the brain calcium-activated neutral protease may participate in the degradation of neuropeptides in vivo.

Amino Acid Sequence↗
PubMed1984

Prevention of varicella in immunocompromised patients on unpredictable occurrence of the disease in a children's ward: vaccine-boostered immune whole blood transfusion (VIB) method.

For prevention of secondary varicella infection in patients whose immunities were extremely impaired by intensive chemotherapy or immunosuppressive agents, we have been using the vaccine-boostered immune whole blood transfusion (VIB) method when there was an unpredictable case of varicella in the children's ward. By this method passive transfer of humoral and cellular immunity is achieved. There have been 25 unpredictable occurrences of varicella or herpes-zoster in the ward of our children's hospital between April 1977 and May 1983 and during these episodes 16 patients, mostly with malignant diseases, have been treated by this method. There has been no case of secondary varicella infection among these patients and no serious troubles associated with the VIB method.

Adolescent↗