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H Hirano

Publications and source records attributed to H Hirano.

At least 235 records · Page 13Linked to original sources
PubMed1995

Immunohistochemical localization of the glucose transporter GLUT1 in choroid plexus papillomas.

Normal chroid plexus tissue and five choroid plexus papillomas were examined with antibody specific for the glucose transporter GLUT1, one isoform of facilitated-diffusion glucose transporters, using the avidin-biotin-peroxidase complex (ABC) technique. GLUT1 in normal choroid plexus was localized at the basolateral plasma membrane of almost all epithelial cells. In three of five tumors, GLUT1 immunoreactivity was observed. A positive reaction was demonstrated at the plasma membrane of tumor cells. The number of GLUT1-positive cells was, however, much smaller than that of the normal choroid plexus. Our results suggest that GLUT1 expression in the choroid plexus is restrained during the course of transformation and that choroid plexus papilloma is composed of various differentiation tumor cells.

Adolescent↗
PubMed1995

Detection of a glycosphingolipid antigen in bladder cancer cells with monoclonal antibody MRG-1.

The monoclonal antibody MRG-1 has been evaluated for the immunohistochemical detection of the type 3 chain of blood group A in human normal bladder epithelium and bladder tumours. Light microscope examination of paraffin sections demonstrated that this antigen was present in normal epithelium and superficial bladder tumour in patients with blood group A or AB, but was absent in the invasive type of bladder tumour. In normal epithelium, the plasma membrane was positive for this antigen, and the cytoplasm was diffusely stained. In superficial transitional cell carcinoma, the plasma membrane was negative, whereas the cytoplasm was intensely stained in the perinuclear region. This pattern was different from that observed for type 1 and 2 group A antigen, which was recognized mainly at the plasma membrane. However, in superficial transitional cell carcinoma, the staining was also seen on the plasma membrane. The pattern of the localization of this antigen in this carcinoma was influenced by the treatment of organic solvents. Electron microscopical observations confirmed that this antigen was localized on the plasma membrane and also in the Golgi apparatus of the superficial tumour. These results proved that the type 3 chain of blood group A is present in human bladder epithelium and low grade tumours in correspondence with the blood type, but disappears in tumours with high malignant potential. However, its expression is independent of the expressions of the other subtypes which have been studied. Furthermore, the changes in the staining pattern caused by pretreatment with organic solvents suggested possible differences in the microenvironment of the glycolipids containing this type of sugar chain.

Animals↗
PubMed1995

Immunohistochemical localization of glucose transporters in human renal cell carcinoma.

The localization of 2 isoforms of glucose transporters (GLUT1 and GLUT4) in 75 patients with renal cell carcinoma was examined immunohistochemically. Paraffin sections were immunostained with either anti-GLUT1 or GLUT4 antibody by the avidin-biotin-peroxidase complex method. In 55 of 75 patients, GLUT1 staining was demonstrated at the plasma membrane of the cancer cells. In the clear cell subtype, 44 of 52 (84.6%) patients were positive for GLUT1. We did not detect positive staining for GLUT1 in the spindle cell type. In the mixed cell subtype, positive staining was recognized in only the areas of clear cell carcinomas (10 of 13; 76.9%). Positive staining for GLUT1 did not show any significant correlation with tumor grade or extent. Heterogeneous expression of GLUT1 was observed in tumor cell mass: some tumor cells were positive for GLUT1, while other cells were not. In adjacent normal tissue, GLUT1 staining was only recognized at the plasma membrane of some renal tubules. GLUT4 staining was not recognized in either tumor or normal tissues.

Carcinoma, Renal Cell↗
PubMed1995

[Chemoembolization of maxillary carcinoma via the superficial temporal artery using a coaxial catheter system].

To perform chemoembolization of maxillary carcinoma, an approach through the superficial temporal artery was applied. A 5-French guiding catheter was advanced into the maxillary artery. The microcatheter was advanced into the terminal portion of the maxillary artery through the guiding catheter, and then carboplatine microcapsules were infused into the feeding artery. Chemoembolization was performed twice in one patient and three times in another. This new method will make it feasible to repeat chemoembolization in patients with head and neck tumors.

Aged↗
PubMed1995

Restricted expression of galactose/N-acetylgalactosamine-specific macrophage C-type lectin to connective tissue and to metastatic lesions in mouse lung.

We investigated expression of macrophage galactose/N-acetylgalactosamine-specific C-type lectin (MMGL) in normal mouse lung tissue and in lungs with metastatic nodules produced by OV2944-HM-1 mouse metastatic ovarian tumour cells. Cells expressing MMGL were detected in tissue sections using a rat monoclonal antibody (mAB) specific for MMGL, mAb LOM-14. The regions containing cells immunostained using mAb LOM-14 were restricted to the connective tissue surrounding blood vessels and respiratory epithelia, whereas alveolar regions of lung parenchyma were essentially devoid of these cells. In contrast, a significant number of cells in the alveolar regions was shown to express Mac-1 antigen (CD11b/CD18) and leucocyte common antigen (CD45). Immunoelectron microscopic study revealed the presence of MMGL in the intracellular vesicles of cells residing in connective tissue. In the tumour-bearing mice, MMGL-positive cells were also present within metastatic nodules. Their localization outside of the nodules was restricted to connective tissue. Cells with Mac-1 antigens were seen both in the nodules and in the alveolar regions. These results indicate that MMGL serves as a unique macrophage marker in mouse lung tissue due to its topographical site-dependent pattern of expression. The present results also suggest a possible involvement of macrophages expressing MMGL in the immune response directed against metastatic tumour cells.

Animals↗
PubMed1994

[Study of X-ray filter and peak kilovoltage in film-screen chest radiographs in regard to detection of simulated pulmonary nodules: comparison between film-screen combination and FCR].

We compared the ability of standard film-screen chest radiographs to detect simulated pulmonary nodules. The radiographs were taken with different X-ray filters and tube voltages. Detection capability was analyzed utilizing receiver operating characteristic (ROC) curves formed from the interpretation of six readers. Nodule detection was slightly better in images obtained with a tube voltage of 135 kVp than with one of 100 kVp (not statistically significant). Approximately equal detection performance was shown by a conventional film-screen system and FCR with three X-ray filter sets: a copper filter backed by aluminium, a tungsten filter backed by yttrium and aluminium, and a lead filter backed by yttrium and aluminium. Results showed less X-ray exposure with the two latter filter sets. Unenhanced FCR images taken with approximately the same X-ray exposure as conventional radiographs showed nearly equal ability to detect the simulated nodules.

Humans↗
PubMed1994

[Study of X-ray filter and peak kilovoltage in Fuji Computed Radiography in regard to the detection of simulated pulmonary nodules].

To determine a suitable combination of X-ray filter and tube kilovoltage for Fuji Computed Radiography (FCR), to provide better detection of pulmonary nodules and reduce patient exposure, we compared observer performance with different X-ray filters and tube voltages. Radiographs were obtained with a copper filter backed by aluminium, with a tungsten filter backed by yttrium and aluminium, and with a lead filter backed by yttrium and aluminium, at both 100 kVp and 135 kVp. Observer performance in detecting simulated lung nodules, which were placed on the posterior aspect of a chest phantom, was compared using receiver operating characteristic (ROC) techniques for each combination of the X-ray filter and tube voltage. The results of the study indicated that 1) nodule detection was superior for the images obtained with 135 kVp as compared with 100 kVp; 2) approximately equal detection rates were obtained for the three X-ray filter sets, although results with the tungsten filter were slightly inferior to the other two filters; and 3) the absorbed dose may be reduced by 30% with the use of a lead filter backed by yttrium and aluminium compared with a copper filter backed by aluminium. We conclude that chest radiography with FCR should preferably be conducted with a higher kilovoltage, e.g., 135 kVp rather than 100 kVp, to ensure a higher detection rate of pulmonary nodules and in conjunction with a lead filter backed by yttrium and aluminium to reduce X-ray exposure to the patient.

Filtration↗
PubMed1994

Induction of heat shock 70 mRNA by cadmium is mediated by glutathione suppressive and non-suppressive triggers.

The induction mechanism of heat shock 70 (Hsp70) gene by cadmium was investigated. In human amniotic WISH cells, Hsp 70 was induced by cadmium in a dose- and time-dependent manner. Cadmium-induced Hsp70 mRNA levels were enhanced 3- to 4-fold after depletion of intracellular glutathione (GSH) by either diethylmaleate or buthionine sulfoximine. Under these conditions, hydrogen peroxide might increase in the absence of substrate for glutathione peroxidase. We found that exogenous hydrogen peroxide alone induced Hsp70 which was further enhanced significantly after GSH-depletion by diethylmaleate. On the other hand, treatment of cells by diethyldithiocarbamate, an inhibitor of superoxide dismutase, induced Hsp70 2-fold over the level of control. This induction was further stimulated by cadmium even in the presence of GSH. Furthermore, a 4-fold increase of intracellular GSH by the treatment of cells with glutathione isopropyl ester did not diminish the cadmium-induced Hsp70. Gel mobility shift assays of nuclear extracts, from these differently treated cells, with oligonucleotide containing a promoter region of Hsp70 gene revealed that the levels of Hsp70 mRNA observed in the present study corresponded to the changes of transcription. These results imply that the induction of Hsp70 mRNA by cadmium is mediated at least partly via reactive oxygen species and attenuated by cellular GSH and that some part of cadmium-induced Hsp70 can not be eliminated by GSH, suggesting that multiple signals are functioning for this induction.

Base Sequence↗
PubMed1994

[Cerebral digital tomosynthetic angiography for planning stereotactic biopsy of brain tumor].

We used cerebral digital tomosynthetic angiography for planning the probe trajectory of stereotactic biopsy of brain tumors in four patients. The probe trajectory was basically planned by MRI examinations. However, cerebral digital tomosynthetic angiography demonstrated detailed three-dimensional vascular anatomy around the brain tumors, and therefore was very helpful in revising the planned trajectory when there was a fairly large vessel likely to cross with it.

Adult↗
PubMed1994

A peptide that stimulates phosphorylation of the plant insulin-binding protein. Isolation, primary structure and cDNA cloning.

The soybean seed basic 7S globulin (Bg) is capable of binding bovine insulin and insulin-like growth factors, and has protein kinase activity which corresponds to about two thirds of the tyrosine kinase activity of the rat insulin receptor. A 4-kDa peptide named leginsulin, which can bind to Bg and compete with insulin for binding to Bg, was isolated from radicles of germinated soybean seeds. The leginsulin had a stimulatory effect on the phosphorylation activity of Bg, suggesting that it is involved in cellular signal transduction. The leginsulin was sequenced by automated Edman degradation and electrospray ionization mass spectrometry. It consisted of 37 amino acid residues with six half-cystines in three disulfide bridges. The mass spectrometric analysis revealed that a portion of the peptide is processed to delete the C-terminal glycine like a number of animal peptide hormones, but not C-terminally amidated. The cDNA encoding the leginsulin was cloned, sequenced and considered to code for a precursor polypeptide consisting of a putative signal peptide, the leginsulin, a linker peptide, a 6-kDa peptide and a C-terminal peptide. Although there is no sequence similarity between the leginsulin and insulin or insulin-like growth factors, the leginsulin is a possible candidate for plant peptide hormones.

Albumins↗
PubMed1994

Increase of hepatic mRNAS of profilin, actin and extracellular matrix proteins after carbon tetrachloride treatment and partial hepatectomy in rats.

The synthesis of liver collagen increases during the fibrotic process after administration of carbon tetrachloride and during regeneration after partial hepatectomy in rats. In the present study, we investigated the behavior of profilin and actin mRNA under such conditions. Profilin and actin mRNA increased after acute and chronic treatments of carbon tetrachloride, which is associated with the increase of fibronectin, type-III and -IV collagen mRNA. Furthermore, a simultaneous expression of profilin, actin and extracellular matrix proteins was observed during the regeneration of rat liver, that is, all mRNAs of these proteins showed biphasic peaks around 6 h and 48 h after partial hepatectomy. These results suggest that possible coupling might occur between the changes of extracellular matrix and the reorganization of actin cytoskeleton in vivo.

Actins↗
PubMed1994

Lectin binding pattern in normal human labial mucosa.

The pattern of lectin binding in normal human labial mucosa was examined by light and electron microscopy using eight different lectins (ConA, LCA, WGA, UEA-1, RCA-1, SBA, DBA and PNA) and compared with the patterns in normal human skin and oesophageal mucosa. As seen by light microscopy, ConA, LCA, and WGA stained cell membranes in all layers of the mucosae. RCA-1 stained the plasma membrane of cells in the basal and middle layers, whereas cells in the superficial layers showed little positive staining. UEA-1, SBA, and PNA stained the cells in the middle layers weakly in some cases. No positive staining for DBA was seen. By electron microscopy, reaction product indicating ConA-binding sites was observed in the plasma membrane, cisternae of the endoplasmic reticulum, nuclear envelope and the Golgi apparatus. Binding of LCA, WGA, and RCA-1 was observed in the plasma membrane. These results show that the binding pattern of PNA, SBA, and RCA-1 in labial mucosa is different from that in the normal skin or oesophageal mucosa, although the labial mucosal epithelium, epidermis, and oesophageal epithelium are all stratified squamous epithelia. These differences in the cell-surface sugar residues are likely to be related to the possible functional differences in these tissues.

Adult↗
PubMed1994

Immunolocalization of glucose transporter GLUT1 in the rat placental barrier: possible role of GLUT1 and the gap junction in the transport of glucose across the placental barrier.

GLUT1 is an isoform of facilitated-diffusion glucose transporters and has been shown to be abundant in cells of blood-tissue barriers. Using antibodies against GLUT1, we investigated the immunohistochemical localization of GLUT1 in the rat placenta. Rat placenta is of the hemotrichorial type. Three cell layers (from the maternal blood side inward) cytotrophoblast and syncytiotrophoblasts I and II, lie between the maternal and fetal bloodstreams. GLUT1 was abundant along the invaginating plasma membrane facing the cytotrophoblast and the syncytiotrophoblast I. Also, the infolded basal plasma membrane of the syncytiotrophoblast II was rich in GLUT1. Apposing plasma membranes of syncytiotrophoblasts I and II, however, had only a small amount of GLUT1. Numerous gap junctions were seen between syncytiotrophoblasts I and II. Taking into account the localization of GLUT1 and the gap junctions, we suggest a possible major transport route of glucose across the placental barrier, as follows: glucose in the maternal blood passes freely through pores of the cytotrophoblast. Glucose is then transported into the cytoplasm of the syncytiotrophoblast I via GLUT1. Glucose enters the syncytiotrophoblast II through the gap junctions. Finally glucose leaves the syncytiotrophoblast II via GLUT1 and enters the fetal blood through pores of the endothelial cells.

Animals↗
PubMed1994

Expression of Lewis(x) sugar structure in the liver metastasis of mouse colon carcinoma (colon 26) cells.

Immunohistochemical aspects of the process of experimentally induced metastasis were examined by light and electron microscopy employing a series of labeled carbohydrate-specific monoclonal antibodies as probes. Liver metastasis was induced by injecting mouse colon carcinoma cell (colon 26) into the spleen of Balb/c mice. Labeled anti-Lewis(x) (Le(x)) antibody stained the metastasized colon 26 cells strongly compared with the heterogeneous and faint staining in non-metastasized tumor foci in the spleen or in the subcutaneous space. Other antibodies having specificities for Lewis-related antigens other than Le(x), e.g. those against Le(y), Le(a), Le(b), sialyl Le(x) and sialyl Le(a), did not show any differences in binding between metastasized cells and non-metastasized tumor foci. Immunoelectron microscopy revealed the expression of Le(x)-carbohydrate in the plasma membranes as well as in the intercellular spaces of metastasized colon 26 cells in the liver. Based on these results, it is likely that sugar chains containing the Le(x)-carbohydrate structure are involved in the interactions between colon 26 cells and hepatic cells during the process of liver metastasis.

Animals↗
PubMed1994

Purification and characterization of a juvenile hormone binding protein from hemolymph of the silkworm, Bombyx mori.

A juvenile hormone binding protein (JHBP) has been isolated from Bombyx mori hemolymph by gel filtration, ion-exchange chromatography, chromatofocusing and hydroxyapatite column chromatography. Gel electrophoresis indicates that the isolated protein is homogeneous in the presence or absence of a denaturing agent. The JHBP in question has a relative molecular mass of 32 kDa, determined by denaturing gel electrophoresis. Chromatofocusing analysis indicated that the JHBP is an acidic protein with pI 4.9. The protein exhibits a dissociation constant of 9.0 x 10(-8) M for JH I, 1.14 x 10(-7) M for JH II and 3.9 x 10(-7) M for JH III, and thus its affinity for JH analogues is in the order of JH I > JH II > JH III. Its amino acid composition indicates that the protein consists of 297 residues of 18 kinds of amino acids. The sequence of the N-terminus of the polypeptide chain was determined for 34 of the first 36 residues: Asp-Gln-Asp-Ala-Leu-Leu- Lys-Pro-?-Lys-Leu-Gly-Asp-Met-Gln-Ser-Leu-Ser-Ser-Ala-Thr-Gln-Gln-Phe-Le u-Glu- Lys-Thr-Ser-Lys-Gly-Ile-Pro-?-Tyr-His-.

Amino Acid Sequence↗
PubMed1994

MR imaging of thymolipoma.

A case of thymolipoma that continued from the level of the thymus gland, drooping inferiorly toward the diaphragm is described. Coronal T1-weighted MR images clearly demonstrated the location and characteristic appearances of the tumor.

Adolescent↗
PubMed1994

CD44 isoform expression mediated by alternative splicing: tissue-specific regulation in mice.

CD44 is a widely distributed cell surface glycoprotein which shows heterogeneity in molecular expression as a result of post-translational modification as well as alternative splicing of CD44 mRNA. Functional studies have indicated that CD44 plays a role as an adhesion molecule and that different CD44-expressing cells differ in their capacities for CD44-dependent ligand binding. These observations have raised the possibility that structural modifications of CD44, including those resulting from alternatively spliced mRNA isoforms, are involved in the functional heterogeneity of CD44. To assess the expression of CD44 isoforms in the mouse, we examined CD44 cDNA by reverse transcription polymerase chain reaction (RT-PCR). Southern blotting of PCR products with a CD44 cDNA probe or with internal oligonucleotides revealed the expression in mouse tumor cell lines and normal tissues of multiple CD44 mRNA products which are larger than that observed in the absence of variable exon expression. Interestingly, different mouse tissues, including lymphoid cells, showed unique patterns of alternative CD44 mRNA in Southern blotting analysis. The use of exon-specific primers allowed detection of multiple alternatively spliced mRNA species involving expression of at least seven variable exons. Cloning and sequencing of these PCR products revealed sequence identity with recently identified genomic CD44 sequences and confirmed that the PCR products correspond to mature mRNA expressing alternatively spliced CD44 exons. Taken together, these findings demonstrate that the mouse expresses multiple variably spliced CD44 isoforms and that expression is regulated in a tissue- and cell-type specific manner.

Alternative Splicing↗