Search PubMed⌕ Search

Biomedical subjects

H Hirano

Publications and source records attributed to H Hirano.

At least 361 records · Page 20Linked to original sources
PubMed1990

Monoclonal antibody to pseudouridine used to develop a radioimmunoassay.

Pseudouridine, a component of tRNA, was modified to yield the derivatives: succinyl, palmitoyl pseudouridine, and protein conjugates. These derivatives were used in preparation of monoclonal antibodies specifically directed to pseudouridine. MAbs from three hybridomas (OAL 881, 812 and 814) were established and shown to be directed to pseudouridine, uridine and uracil. OAL 881 was equally reactive with the three substrates, OAL 812 showed the same reactivity for pseudouridine and uracil, while OAL 814 showed a reactivity mainly for pseudouridine. MAb OAL 814 was used in a radioimmunoassay (RIA) system unique for pseudouridine. A good dose-response curve was observed in the range between 31.3 and 2000 nmol/ml. Intra- and inter-assay CV values were below 4.1% and 7.4% respectively, and good results were obtained from recovery of added material and dilution tests. The ratio of pseudouridine/creatinin in urine was significantly higher in patients with cancer than in normal subjects.

Antibodies, Monoclonal↗
PubMed1990

B-B cell interaction involved in polyclonal B cell activation is restricted by I-A but not by I-E molecules.

We have previously demonstrated that the class II MHC restricted B-B cell interaction is involved in the polyclonal differentiation of unprimed murine B cells into IgM-producing cells induced by a T cell-derived lymphokine B151-TRF2 or bacterial LPS. The present study has addressed the question of whether I-A and/or I-E molecules function as restriction elements for the B-B cell interaction. The results revealed that (B10 x B10.BR)F1(H-2b/k) B cells could be separated into I-Ab- and 1-Ak-restricted subpopulations by their ability to bind to B10(H-2b) or B10.BR(H-2k) B cell monolayers, whereas an I-E-restricted F1 B cell population was not obtained. Moreover, B10-derived B cells isolated from (B10 + B10.BR) - (B10 x B10.BR)F1 but not from B10 - (B10 x B10.BR)F1 radiation-induced bone marrow chimeras acquired newly the ability to co-operate with mitomycin C-treated auxilary B cells expressing I-Ak but not I-Ek molecules. Thus, these results indicate that I-E molecules, unlike I-A molecules, do not serve as restriction elements for the B-B cell interaction, and that I-A and I-E molecules on B cells play functionally disparate roles in the activation of polyclonal B cells.

Animals↗
PubMed1990

Alternation of gastric mucosal glycoprotein (lectin-binding pattern) in gastric mucosa in stress. A light and electron microscopic study.

Gastric mucosal cells of the rat glandular stomach were studied by light and electron microscopic procedures by use of lectins in the development of acute gastric mucosal lesions. Effects of the H2-receptor antagonist sofalcone (2'carboxymethoxy-4,4'-bis 3-methyl-2) and truncal vagotomy with pyloroplasty on lectin binding sites and distribution were also investigated. Biotinylated lectins in combination with ABC (avidin-biotinyl peroxidase complex) method were used for light and horseradish peroxidase (HRP)-labeled lectins for electron microscopic studies. Gastric mucosal cells showed the specific binding pattern for each lectin by light microscopy. Especially, binding sites and distribution of peanut agglutinin (PNA) were characteristic after induction of stress, truncal vagotomy, and administration of each drug. Staining and distribution increased in the gastric mucosa upward and downward after that. In electron microscopic studies, PNA strongly stained the membranes of the intracellular secretory canaliculi of a parietal cell. These results suggested that alternation of binding sites and distribution was regulated by change of gastric mucosal blood flow and of acidity in the parietal cells. Therefore, increase of glycoconjugate distribution is supposed to be a possibility of cytoprotective effect for a change of environment in the parietal cells.

Animals↗
PubMed1990

Changes in pulmonary tissue of patients with congenital heart disease and Down syndrome: a morphological and histochemical study.

Pulmonary tissues obtained from 12 individuals suffering from congenital heart disease associated with Down syndrome were examined by light and transmission electron microscopy and compared with those of 29 cases without the syndrome. Alkaline phosphatase (ALPase) activity, which is known to play an important role in the secretion of pulmonary surfactant, was histochemically examined and compared. The major changes found in the pulmonary tissues examined from pulmonary hypertensive patients were increase in the number of type II alveolar cells and in ALPase activity. ALPase activity was positive in the plasma membrane of type II cells and in the limiting membrane of the osmiophilic bodies contained within them. These changes were more conspicuous and detected at an earlier age in the pulmonary hypertensive individuals with Down syndrome than in those without the syndrome. These observations indicate that the acinar region in pulmonary tissue is affected at an earlier stage, and that changes in the production and secretion of pulmonary surfactant occur, in patients with Down syndrome. Early surgical treatment is recommended for them.

Alkaline Phosphatase↗
PubMed1990

Effects of ultraviolet B irradiation on lenticular riboflavin metabolism and high-molecular-weight-protein aggregation.

We investigated the effects of ultraviolet B (UVB) irradiation on the formation of ester forms of riboflavin and of high-molecular-weight (HMW) protein aggregates and on lenticular riboflavin-binding capacity (LRBC). Esterification of riboflavin decreased as the duration of UV irradiation increased, suggesting the irradiation-induced denaturation of the apoenzyme of synthetases of ester forms of riboflavin. UVB irradiation of lens homogenate supplemented with riboflavin increased LRBC and the formation of HMW protein aggregates, while gamma-crystallin was decreased. These results are consistent with those of our earlier studies in which we obtained data suggesting that, upon exposure of rat lens homogenate to fluorescent light, photosensitized riboflavin may bring about cross-linking of lens protein. Our data demonstrate that the photosensitivity of lenticular riboflavin is increased by longer periods of UV irradiation.

Animals↗
PubMed1990

Comparison of amniotic fluid disaturated phosphatidylcholine, phosphatidylglycerol and lecithin/sphingomyelin ratio in predicting the risk of developing neonatal respiratory distress syndrome.

One hundred forty-one amniotic fluid samples were analyzed for disaturated phosphatidylcholine (DSPC), phosphatidylglycerol (PG) and the lecithin/sphingomyelin (L/S) ratio. The L/S ratio was measured by two-dimensional thin layer chromatography. Mature levels (positive) were defined as an L/S ratio of 2:1 or more, a DSPC level of 100 micrograms/ml or more and a detectable level of PG. The DSPC value agreed with the L/S ratio in 114 samples (80.9%). Fourteen of 17 infants with respiratory distress syndrome (RDS) (82.4%) had immature L/S ratios and immature DSPC levels. RDS developed in 16 of 40 (40%) children with immature L/S ratios, and in 15 of 33 (45.5%) children with immature DSPC levels. The true-positive rates of the L/S ratio and DSPC levels were 99.0 and 98.1%, respectively. PG had a low true-negative rate, as only 17 of 67 (25.4%) samples without detectable levels of PG were associated with RDS. However, when PG was present, it had a 100% predictive value of no-RDS. In conclusion, DSPC is nearly equal to the L/S ratio measured by two-dimensional as concerns diagnostic accuracy. PG is useful as an additional index for predicting lung maturation.

Amniotic Fluid↗
PubMed1990

[Cytochemical study of Mg2(+)-ATPase and ALPase activity in human meningiomas].

Ultracytochemical features of microvessels and tumor cells of the human meningiomas were examined by light and electron microscopy with special reference to the distribution of Mg2(+)-ATPase and alkaline phosphatase (ALPase) activity on the walls of the vessels and tumor cell surfaces. Materials used were 4 cases of meningiomas, 2 of which were meningotheliomatous type, one fibroblastic type and one malignant meningioma respectively. For ultracytochemistry, specimens were quickly fixed in an ice-cold 0.1 M cacodylate buffer containing 8% sucrose (pH 7.2) for one hour and transferred to a substrate solution for detection of Mg2(+)-ATPase and ALPase. The preparations were incubated at 37 degrees C for 15-30 min in the medium described by Mayahara et al. for ALPase and for 15-20 min in the medium described by Wachstein and Meisel. The control samples were incubated in a medium containing 1 mM Bromotetramisole for ALPase and also in a substrate free medium for Mg2(+)-ATPase. At the light microscopy, Mg2(+)-ATPase and ALPase activities appeared to be mainly restricted to the capillary wall and around or in the tumor cell nest showing whorl formation. Both enzyme activities were negative in the control study. By electron microscopy, reaction products representing Mg2(+)-ATPase activity were distributed in the basolateral plasma membrane of the endothelial cells on the surface of the pericytes and on the surface of the tumor cells. Reaction products of ALPase activity located mainly on the abluminal surfaces of the endothelial cells and in some specimen on both luminal and abluminal surfaces of those cells. Intense reaction products were distributed evenly on all round surfaces of the tumor cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Anticoagulant therapy in obstetrical disorders].

Three kinds of anticoagulant therapy for obstetrical DIC were studied. 1. Antithrombin-III (AT) or gabexate mesilate for acute DIC, mainly for abruptio placentae. 2. Heparin or heparin-AT combination therapy for toxemia pregnancy. 3. Low molecular weight heparin (LMWH) for fetus of intrauterine growth retardation (IUGR). The results obtained were as follows, 1. a) Platelet count, and fibrinogen were significantly increased in AT therapy group compared with gabexate mesilate group. b) In clinical manifestation, renal failure and hemorrhagic diathesis were improved especially in AT group. 2. In heparin-AT group, high systolic blood pressure was improved during administration of AT, the high level of thrombin antithrombin complex was also found in these period. 3. a) The improvement of the gain of estimated fetal body weight was found after administration of LMWH. b) Redistribution of blood flow in one case of severe IUGR was observed during administration of LMWH.

Antithrombin III↗
PubMed1990

[Step section preparation of transbronchial lung biopsy material in diffuse lung disease].

We retrospectively prepared step sections of the transbronchial lung biopsy (TBLB) materials which revealed nondiagnostic findings in their original sections in patients with diffuse lung disease, and evaluated the significance of the examination of step sections in the diagnosis of diffuse lung disease. Of 131 cases with nondiagnostic TBLB findings, the preparation of step sections resulted in specific findings in 6 cases (malignancy 3 cases, tuberculosis 1 case, cryptococcosis 1 case and viral infection 1 case), and histopathological changes consistent with the clinical diagnosis in 25 cases. The step section preparation was especially useful for the detection of epithelioid granuloma and tumor tissue in patients with sarcoidosis and carcinoma, respectively, while its contribution to the diagnosis of collagen-vascular disease, hypersensitivity pneumonitis, atypical pneumonia and pneumoconiosis was relatively small. The step section preparation was also useful for the detection of bronchiolitis obliterans. In addition, step sections uncovered clinically unnoticed infection (purulent exudate in the alveolar space) in 6 cases, 3 of whom actually developed pneumonia thereafter. Thus, the preparation of step sections was considered to be useful clinically in 37 cases (28.2%). The preparation of step sections is recommended before a further diagnostic procedure is chosen, when TBLB performed in patients with diffuse lung disease reveals nondiagnostic findings.

Biopsy↗
PubMed1990

[Alteration of the gastric mucosal glycoprotein in stress].

Many studies have postulated the role of gastric acid and mucosal microcirculation in the development of gastric ulcer. We considered that gastric mucosal glycoprotein played one of the most important roles as the defensive factors of te gastric mucosa. The purpose of this study is to investigate te location and distribution of glycoprotein in the gastric mucosa in normal and stressful condition. Male Wistar rats, weighing 250 g were used as the experimental animals. Alternation and distribution of glycoprotein in the gastric mucosa were studied by light and electron microscopic examination employing HRP-labeled lectin such as PNA, DBA, ConA, RCA, SBA, WGA and UEA-1 as a parameter before and after the development of stress ulcer. Around Thirty percent scalding burn of the rat body surface area was created. At 2, 5 and 24 hours after burn induction, the gastric mucosa was examined. PNA-binding sites which were primarily localized to the generative cell zone in the control rat appeared to extend from the upper layer to the intermediate or the basal layer of the gastric mucosa in accordance with the development of stress ulcer after burn. Most of the binding sites was detected in the parietal cells particularly along microvilli in the intracellular secretory canaliculi. The tubulovesicular system in the parietal cells became stainable with PNA in the stress-loaded rats. Alternation and binding pattern of lectin, especially of PNA may indicate the local response of the parietal cells of the gastric mucosa against the stress.

Animals↗
PubMed1989

Changes in lectin binding pattern of gonads of developing mice.

Changes in lectin binding of developing fetal mouse testes and ovaries were examined by light and electron microscopy, with much attention paid particularly to those in carbohydrates of germ cells. Characteristic binding patterns were observed with three lectins (BPA, GS-I, and GS-II) in the germ cells and the somatic cells during the process of testicular and ovarian development. GS-I and BPA, which showed similar binding patterns, preferentially bound to the plasma membrane and small dense bodies (SDB) of germ cells in both testes and ovaries during the 12th to 14th day post coitum (p.c.). In the fetal testes on day 16 p.c., the reaction with both GS-I and BPA completely disappeared. While, in the ovaries, a weak reaction with these lectins was retained as it was in germ cells until the 16th day p.c. The reaction with GS-II was restricted to Sertoli cells in the fetal testes during the 12th to 14th day p.c., and thereafter disappeared on day 16 p.c. The distribution of GS-II binding sites was in agreement with that of the glycogen granules. No positive staining with GS-II was seen in the ovaries throughout their development. These results indicate that certain glycoconjugates containing D-galactose and N-acetyl-D-galactosamine residues are expressed on the cell surface and in the SDB of germ cells during the period of the 12th to 14th day p.c., and that striking changes in function as well as in structure may take place in both germ cells and somatic cells during the 14th to 16th day p.c. in association with testicular and ovarian development.

Animals↗
PubMed1989

Differences in lectin binding patterns of normal human endometrium between proliferative and secretory phases.

Lectin binding patterns in normal human endometrium were examined by light and electron microscopy using seven different lectins (ConA, WGA, RCA, PNA, UEA-1, DBA, and SBA). For light microscopic observations, criteria based on the incidence and intensity of cells positive for the lectin staining were adopted to evaluate the different staining patterns of the proliferative and secretory endometria obtained by the avidin-biotin-peroxidase complex (ABC) technique. At the light microscopic level, ConA, WGA, and RCA stained endometrial glandular cells in both phases. The number of PNA-positive cells with the binding sites entirely limited to the apical surface tended to be reduced slightly in the secretory phase. UEA-1 weakly stained the apical surface of glandular cells in the proliferative phase but not in the secretory phase. Among the lectins used in this study, DBA and SBA displayed remarkable changes between the phases. That is, in the proliferative phase they produced only a faint or slight positive stain at the apical surface, but the incidence and intensity of DBA- and the SBA-positive glandular cells increased in the secretory phase. By electron microscopy, the reaction product of ConA was observed in the plasma membrane, endoplasmic reticulum, nuclear envelope, and the Golgi apparatus, and the binding sites of RCA and DBA were observed in the plasma and Golgi membranes. Between both phases, the reactivity of ConA and RCA showed almost no change. However, the secretory endometrial cells containing the DBA-positive Golgi apparatus were markedly increased in number compared with the proliferative ones bearing the lectin-positive organelles.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Distribution of glycoconjugates on the plasma membrane and on membranes of the open-canalicular system in human platelets. A cytochemical study.

Distribution of carbohydrate moieties in the membrane system of the human blood platelet was studied by electron microscopy employing lectins as a probe. Glutaraldehyde-fixed platelets were treated with biotinylated-lectins (ConA, RCA, WGA, PNA, SBA, DBA and UEA-1) and labeled with horseradish peroxidase-conjugated avidin. Among the lectins used, ConA bound uniformly to the plasma membrane as well as to the membrane of the open-canalicular system (OCS). Other lectins showed more or less reduced binding on the OCS membrane compared with that on the plasma membrane, indicating that there exist regional differences in the distribution pattern of glycoconjugates in the membrane system of the platelet. The relationship of the distribution pattern of the glycoconjugates with the distribution of the major platelet glycoproteins GPIb and GPIIbIIIa is discussed.

Blood Platelets↗
PubMed1989

Microsequence analysis of winged bean seed proteins electroblotted from two-dimensional gel.

Electroblotting method employing a semidry blotting apparatus for the subsequent protein microsequence analysis (Hirano, 1987) was improved. This method is convenient and allows rapid and efficient transfer of the proteins from a polyacrylamide gel (1 mm thick) onto the Polybrene-coated glass-fiber sheet or polyvinylidene difluoride membrane filter in only 20 min. The electroblotted proteins could be sequenced directly with the gas-phase protein sequencer at a 20-pmole level. This method was applied to the sequence analysis of winged bean seed proteins. A portion of the crude extracts from only one-twentieth of a seed of the winged bean was separated by two-dimensional polyacrylamide gel electrophoresis and electroblotted, and the N-terminal amino acid sequences of the blotted proteins were analyzed. The sequences of about 60% of the blotted major proteins, including nine Kunitz trypsin inhibitor-like proteins with heterogeneity in the N-terminal sequences, a protein that has a homologous sequence to the leghaemoglobin, nitrogen-fixing root nodule-specific protein, and a soybean basic 7S globulin-like protein could be easily identified.

Amino Acid Sequence↗
PubMed1989

The outer capsid protein of rice dwarf virus is encoded by genome segment S8.

The nucleotide sequence of DNA complementary to the eighth largest (S8) of the 12 genome segments of rice dwarf virus was determined. This genome segment is 1424 nucleotides in length and has a single long open reading frame extending 1260 nucleotides from the first AUG triplet (residues 24 to 26). The predicted translational product comprises 420 amino acids and has an Mr of 46,422. The amino acid sequences of several peptide fragments of the major outer capsid protein were found to be contained in the predicted translational product of the above nucleotide sequence. This protein, previously reported to be 43K, is encoded by genome segment S8 and therefore renamed the 46K protein.

Amino Acid Sequence↗
PubMed1989

Localization of granular components in ADP- and/or teleocidin-stimulated human blood platelets as revealed by immunocytochemical methods.

Morphological aspects of the platelet release reaction induced by adenosine 5'-diphosphate (ADP) and/or teleocidin (a tumor promoter) in the presence of aspirin were studied by transmission electron microscopy. Human platelet-rich plasma treated with reagents at 37 degrees C for 1-5 min was fixed with aldehyde and embedded in Epon or Lowicryl K4M. Addition of ADP (10 microM) resulted in the centralization of granules without granule release, while teleocidin (100 ng/ml) induced the swelling of the open canalicular system (OCS) and the release of alpha-granules without centralization of these granules. When both ADP and teleocidin were added successively, a synergistic effect was predominant; and both alpha- and dense-granules were discharged from the cytoplasm. Postembedding immunocytochemical studies employing specific antibodies against various granular components in combination with protein A gold as a label revealed that, following the administration of teleocidin, several components of alpha-granules such as beta-thromboglobulin and platelet factor 4 moved into the swollen OCS, while the dense-granule component, serotonin, did not. When both teleocidin and ADP were administered, both alpha-granular and dense-granular components moved into the swollen OCS.

Adenosine Diphosphate↗
PubMed1989

Effects of pH and light exposure on the riboflavin-binding capacity in the rat lens.

To elucidate the binding mode of riboflavin to rat lens protein, we examined the effects of light exposure, different pH (4.0, 7.0 and 9.0) and dialysis on the lenticular riboflavin-binding capacity (LRBC). LRBC increased remarkably by light exposure, irrespective of pH. By dialysis, LRBC of a light-exposed incubation mixture decreased remarkably at pH 9.0, however, at pH 4.0 and 7.0, dialysis did not affect it significantly. Decrease in LRBC in light-exposed dialyzed samples at the higher pH may result from release of dialyzable bound riboflavin from binding protein. These data suggest that the dialyzed bound riboflavin at the higher pH may be responsible for a photosensitization of lens protein.

Animals↗