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T Hida

Publications and source records attributed to T Hida.

At least 109 records · Page 6Linked to original sources
PubMed1992

[Scanning and transmission electron microscopic studies of the ultrastructure of the corneal endothelium in developing human eye].

The ultra-microstructure of the human corneal endothelium was examined by scanning and transmission electron microscopy. The samples were corneas of 26 human eyes taken from fetuses of 5-22 weeks gestation and a newborn 10 months after birth. Corneal endothelium appeared at the seventh or eighth week after gestation. Initially, they formed an irregular structure of two to three layers. From the 17th week of gestation they formed a single layer, and assumed the form of a cuboidal epithelium. Scanning and transmission electron microscopy showed numerous microvilli protruding towards the anterior chamber. Within the microvilli uniform microtubules were observed. By the 20th week, these microvilli disappeared, and subsequently, a single long narrow cilium appeared in the center of each cell. Each cilium had an axial filament complex structure. This cilium involuted as development progressed, and was barely visible by the 10th month after birth. The significance of this cilium is not clear.

Endothelium, Corneal↗
PubMed1992

Morphological and histochemical studies of goblet cells in developing human conjunctiva.

This study deals with the development of the human conjunctival goblet cells. Fifty-six eyes of human embryos and fetuses ranging from 5 to 41 weeks of gestational stage were used. The distribution of glycosaminoglycans in the goblet cells was investigated with 1% alcian blue (pH 2.5) staining. For identifying the types of glycosaminoglycans, enzyme digestion methods were carried out with streptomyces hyaluronidase, chondroitinase AC, chondroitinase ABC, or sialidase (neuraminidase). At 9 weeks of gestational age, goblet cells appeared in the fornix region of the conjunctiva and extended toward the palpebral and bulbar regions. Histochemical studies with enzyme digestion methods revealed the existence of sialomucin in the goblet cells from 9 weeks. This finding suggested that the goblet cells first appeared in the fornix area, extending toward the palpebral region, then toward the bulbar region, and containing sialomucin from their early stage of development.

Chondroitin Lyases↗
PubMed1992

[A juvenile case of mesenchymal chondrosarcoma originating from soft tissue in the orbit].

Mesenchymal chondrosarcoma is a very rare occurrence in the orbit. A 10-year-old girl presented with right exophthalmos. Computed tomography revealed a round tumor inside the muscular cone of the right orbit. There was a sign of slight calcification inside the tumor. The tumor was surgically removed by the Krönlein-Berke procedure. Histopathological examination showed undifferentiated mesenchymal cells and cartilage tissue. A recurrent tumor was found in the same location 34 months after the surgery, which was removed by frontal approach saving the globe with normal function. Histopathology of the recurrent tumor revealed a slight difference from the primary tumor, showing hemangiopericytoma pattern without cartilage components. Immunohistochemical studies of the primary and recurrent tumors showed their cells to be positive for antifactor VIII and S-100, and negative for myoglobin and monoclonal antibody to muscle actin. Electron microscopically these undifferentiated cells had large nucleus and very scanty cytoplasm, mostly containing glycogen granules. This is probably the first description of a juvenile case of mesenchymal chondrosarcoma originating from soft tissue in the orbit.

Child↗
PubMed1991

Preferential expression of c-kit protooncogene transcripts in small cell lung cancer.

As an initial step to understand rapid growth of small cell lung cancer (SCLC), a complementary DNA library prepared from a SCLC cell line was screened with viral oncogene probes encoding protein-tyrosine kinases, which are known to play an important role in regulation of cell growth. Fifteen clones hybridizing with v-fms probe were isolated, and, by partial sequence analysis, four of them were identified to be c-kit protooncogenes. Northern blot study demonstrated that most of the SCLC tumors and cell lines expressed c-kit transcripts, while non-SCLC tumors and cell lines did not. Neither amplification nor rearrangement of the c-kit gene was demonstrated in SCLC cell lines by Southern blot analysis, however. Our results suggested that c-kit expression in SCLC reflects the unique biological nature of the tumor cells different from non-SCLC and further suggested that the c-kit product may participate in autocrine or paracrine stimulation of SCLC growth.

Base Sequence↗
PubMed1991

Different behaviour of two distinct types of Fc gamma receptor on guinea-pig peritoneal macrophages during phagocytosis of soluble immune complexes: identification of an intracellular pool for one of the receptors.

Guinea-pig peritoneal macrophages express two distinct types of Fc receptor for IgG (Fc gamma R): one specific for IgG2 (Fc gamma 2R) and the other for both IgG1 and IgG2 (Fc gamma 1/gamma 2R). When we employed flow cytometry for an assay, we found that the amount of ovalbumin (OA) complex of homologous IgG2 antibody bound on the surface of macrophages rapidly decreased during the phagocytosis in the presence of an excessive amount of the complex. This reduced binding capacity of the cells was gradually restored by incubating the cells in the complex-free medium, which showed that the Fc gamma Rs are consumed during the phagocytosis and again expressed on the cell surface. Flow cytometry with monoclonal anti-Fc gamma 2R Fab' and anti-Fc gamma 1/gamma 2R Fab' revealed that only the Fc gamma R type bound to the immune complex was selectively internalized, whereas another Fc gamma R type unbound persisted on the cell surface during the reaction. In addition, the amount of Fc gamma 1/gamma 2R on the cell surface was found to increase to a greater extent than did that of Fc gamma 2R, when phagocytosis was terminated by the removal of the immune complex. This result suggests that Fc gamma 1/gamma 2R is recruited from some intracellular store. In fact, we were able to demonstrate the existence of the membrane-associated intracellular Fc gamma 1/gamma 2R pool that increases the binding capacity of anti-Fc gamma 1/gamma 2R F(ab')2 by treatment of macrophages with saponin, and by fractionation of homogenized macrophages by sucrose density gradient centrifugation. The different behaviour of these two Fc gamma R type, thus shown, may cause the relatively sustained phagocytosing activity mediated by Fc gamma 1/gamma 2R compared with that caused by Fc gamma 2R; the former continued at least up to 6 hr, while the latter ceased within 2 hr.

Animals↗
PubMed1991

TAN-931, a novel nonsteroidal aromatase inhibitor produced by Penicillium funiculosum No. 8974. I. Taxonomy, fermentation, isolation,characterization and biological activities.

A novel nonsteroidal aromatase inhibitor, TAN-931, was isolated from the culture filtrate of a soil isolate fungus, No. 8974. The strain was identified as Penicillium funiculosum No. 8974. TAN-931 inhibited human placental and rat ovarian aromatase activity, and the IC50 value was 17.2 and 162 microM, respectively. The inhibition of human placental aromatase was uncompetitive with respect to androstenedione conversion with a Ki value of 40 microM. When TAN-931 was subcutaneously administered at doses of 25, 50 and 100 mg/kg (once/day, x4) to 20-day-old female Sprague-Dawley rats treated with gonadotropin, the plasma estradiol-17 beta level and the weight of ovaries and uterus were markedly reduced in a dose-dependent manner. The in vivo inhibitory activity of TAN-931 was more potent than that of 4-hydroxyandrostenedione. Consecutive administration of TAN-931 (100 mg/kg, sc, twice/day, x 7) to 9-week-old male Sprague-Dawley rats did not induce any adrenal hypertrophy even though administration of aminoglutethimide caused 2-fold enlargement of the adrenal under the same conditions. Specific binding of TAN-931 to the estrogen receptor from a human breast cancer cell line, MCF-7, was not detected.

Adrenal Glands↗
PubMed1991

TAN-931, a novel nonsteroidal aromatase inhibitor produced by Penicillium funiculosum No. 8974. II. Structure elucidation, chemical modification and biological activity.

The structure of TAN-931, a novel nonsteroidal aromatase inhibitor, was determined by chemical reactions and spectral analyses including 2D NMR experiments to be 4-(2,6-dihydroxybenzoyl)-3-formyl-5-hydroxybenzoic acid. Several derivatives of TAN-931 were prepared, and it was found that the 3-formyl and 2'- and/or 6'-hydroxyl groups play an important role in its inhibitory activity. Among the compounds synthesized, 4-(2,6-dihydroxybenzoyl)-3-formyl-5-methoxy-N,N-dimethyl-benzamide was found to be more effective than TAN-931 when administered orally.

Administration, Oral↗
PubMed1991

The p53 gene is very frequently mutated in small-cell lung cancer with a distinct nucleotide substitution pattern.

The p53 gene has been implicated as a tumor-suppressor gene whose disruption is involved in the pathogenesis of common human cancers. The results of extensive analysis of p53 mutations in non-small cell lung cancers (NSCLCs) have revealed that p53 is mutated in 45% of NSCLC with base changes different from those of colon cancer. In this study, we examined 17 SCLC tumor samples taken directly from 15 patients as well as the corresponding nine tumor cell lines. Mutations changing the p53 coding sequence were found in 11 of 15 patients (73.3%) and showed a similar but distinct nucleotide substitution pattern compared with NSCLC, suggesting that a different mutagenic process is involved. In addition, a strong correlation was seen between the presence of p53 mutations in tumors and the successful establishment of the corresponding cell lines, suggesting that p53 mutations can confer a selective growth advantage in vitro (and probably also in vivo).

Amino Acid Sequence↗
PubMed1991

Epitope analysis of cluster 1 and NK cell-related monoclonal antibodies.

By flow cytometric assays, we tested the antibodies of the Second International Workshop on Small Cell Lung Cancer Antigens against 20 normal peripheral leukocytes, four small cell lung cancer (SCLC) cell lines (one classic type, and three variant type) and one gastric cancer line (KATO 3). Thirteen antibodies (Code # 4, 12, 21, 31, 34, 41, 48, 58, 60, 61, 74, 77, 82) among 98 registered antibodies showed a very similar pattern to antibody NE150, which was previously characterised as SCLC cluster 1. Since NE150 showed a positive reaction to the natural killer (NK) cell population, the serological specificity was compared with NK cell-associated antibodies, NKH1 (CD56), Leu7 (CD57) and Leu11 (CD16). Only NKH1 antibody showed a similar pattern to NE150, when tested against various target cells including SCLC lines and peripheral leukocytes, suggesting that NKH1 is a cluster 1 antibody, although it was already classified as CD56 of hematopoietic cells. By sequential immunoprecipitation, the antigen detected by NE150 antibody was depleted by preincubation with NKH1 antibody, but the reactivity of NE150 was not inhibited by NKH1 antibody, suggesting that NE150 and NKH1 detect different epitopes on the same antigen molecule. Epitope analysis was also conducted with 13 antibodies of cluster 1. Ten were found to detect the same epitope as NE150. The other three did not inhibit the binding of NE150 or NKH1, suggesting that there are at least three epitopes. Since the cluster 1 antibodies were demonstrated to detect NCAM, the present results suggest the presence of at least three epitopes on this molecule.

Antibodies, Monoclonal↗
PubMed1991

Coexpression of the stem cell factor and the c-kit genes in small-cell lung cancer.

Stem cell factor (SCF) is a pluripotent growth factor which is suggested to play an important role in proliferation and differentiation in various types of fetal and adult tissues as the ligand of the c-kit proto-oncogene product. However, very little is known about expression of the SCF gene in human malignancies. We analysed DNA and RNA extracted from 28 cell lines and 16 fresh tumor specimens of lung cancer as well as 24 cancer cell lines of various origin for SCF expression. Now we report that the SCF gene is expressed in a wide variety of human cancers including lung cancer, in marked contrast to c-kit, which is expressed in very few types of cancers. As a consequence, coexpression of both the ligand and the receptor is seen only in small-cell lung cancer, suggesting possible involvement of autocrine stimulation via this ligand-receptor system in the pathogenesis of this aggressive cancer. In addition, this study revealed that the human SCF gene is transcribed into two major forms of alternatively spliced mRNAs with different molar ratio in fetal, adult and malignant tissues.

Base Sequence↗
PubMed1991

[Macular hole].

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Humans↗
PubMed1990

Cyanoacrylate tissue adhesive in the management of recurrent retinal detachment caused by macular hole.

Nine eyes of nine patients with rhegmatogenous retinal detachment caused by a macular hole were treated by the transvitreal application of cyanoacrylate tissue adhesive to the macular hole. Eight of the nine eyes had previously failed conventional vitreous surgery with gas tamponade and laser photocoagulation. Eight eyes (89%) were completely reattached with a minimum follow-up of three months. In the successfully treated eyes, post-operative visual acuity was 20/200 in two eyes, 20/400 to 5/200 in five eyes, and less than 5/200 in one eye. Direct sealing of macular holes in difficult cases may obviate the need for extended intraocular tamponade or macular buckling with their associated complications.

Aged↗
PubMed1990

Histochemical studies on hyaluronic acid in the developing human retina.

Changes in the distribution of hyaluronic acid in the developing human retina were investigated histochemically with alcian blue staining and the Streptomyces hyaluronidase digestion method using 56 human embryos and fetuses ranging from 5 to 41 weeks of gestational age. Hyaluronic acid was first detected in the inner layer of the retina at 12 weeks. The site of accumulation extended towards the outer layer by 20 weeks. At the neonatal stage, longitudinal fibers, possibly the processes of Müller cells, were proved to contain hyaluronic acid. These findings suggest that Müller cells produce hyaluronic acid transiently from 12 weeks' gestation to the neonatal stage.

Aged↗
PubMed1990

[Morphological and histochemical studies on the development of human conjunctival goblet cells].

This report deals with the development of human conjunctival goblet cells. Fifty-six eyes of human embryos and fetus ranging from 5 to 41 weeks of gestational age were used in this study. Glycosaminoglycans in the goblet cells were investigated histochemically using 1% alcian blue staining (pH = 2.5) and PAS reagent staining and sialidase (neuraminidase) digestion. At 8 weeks, goblet cells appeared in the forniceal area, and they extended to the palpebral and bulbar conjunctiva. These cells were already similar to adult goblet cells. Alcian blue staining and the enzyme digestion method revealed the existence of sialic acid in the goblet cells from 9 weeks. These results suggest that at the early developmental stage the goblet cells develop from the forniceal area. It is also indicated that the goblet cells in the early developmental stage are already similar to cells in the adult stage because they contain mainly sialic acid as glycosaminoglycans.

Adult↗
PubMed1989

Chemosensitivity and radiosensitivity of small cell lung cancer cell lines studied by a newly developed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) hybrid assay.

The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) hybrid assay was developed by technically combining the human tumor clonogenic assay and the MTT assay to make the most of both assays. This assay was able to estimate the in vitro growth of cultured cell lines and of tumor cells in pleural effusion, suggesting the possibility of its use for assessment of chemosensitivity and radiosensitivity of fresh tumor samples. Multiple cell lines [including morphological and/or phenotypical in vitro converters and cisplatin (CDDP)-resistant lines] were established from three patients with small cell lung cancer at different stages of the disease. Chemosensitivity of these cell lines to four commonly used chemotherapeutic drugs was tested by the MTT hybrid assay. SK1 and SK3 lines were established from Patient S. K. before and after chemotherapy and radiotherapy, respectively. SK3/CDDP, a CDDP-resistant line derived from the SK3 line, was 30-fold more resistant to CDDP [50% inhibiting dose (IC50), 21.5 micrograms/ml] than the SK1 line. In Patient M. O., MOA2/CDDP, a CDDP-resistant line derived from MOA2 (an in vitro converter from the MO line), was 41-fold more resistant to CDDP (IC50, 37 micrograms/ml) than the parent MO line. From Patient T. M., TM1 and TM2 lines were established before and after chemotherapy, respectively. The latter showed 6-fold more resistance to CDDP than the former. Chemosensitivity of these lines to three other drugs, 4-hydroperoxycyclophosphamide, Adriamycin, and etoposide, suggested cross-resistance between CDDP and 4-hydroperoxycyclophosphamide. Radiosensitivity study was also carried out with the MTT hybrid assay. The MOA2 line was more resistant [Do, 3.0 Gy; extrapolation number (n), 4.0] than the parental MO line (Do, 1.6 Gy; n, 2.1). There was no clear difference in radiosensitivity between the cell lines established before and after radiation therapy in Patient S. K.

Antineoplastic Agents↗
PubMed1989

Expression and amplification of myc gene family in small cell lung cancer and its relation to biological characteristics.

Eighteen small cell lung cancer (SCLC) lines (including nine lines established by this group) as well as 31 tumor samples from 23 SCLC patients were examined for the surface antigen phenotype and the expression and amplification of the myc gene family. The expression of NE-150 neuroendocrine, PE-35 panepithelial and OE-130 epithelial antigens corresponded well with the level of biomarkers of SCLC lines, i.e., the NE-150+/PE-35+/OE-130- phenotype corresponded to classic type, while the other phenotypes such as NE-150+/PE-35-/OE-130- to variant type. In tumor specimens, most classic SCLC (consisting of oat cell type and intermediate cell type, subtype a) showed NE-150+/PE-35+/OE-130- phenotype, while small cell-large cell carcinoma (intermediate cell type, subtype b) expressed various phenotypes. The amplification of the myc gene family was observed in nine out of 18 lines (50%) and five out of 23 patient tumors (22%). Higher levels of expression of either c-myc, N-myc, or L-myc were detected in 16 out of 18 lines (89%) and in five out of six patient tumors (83%), when compared with that of normal or fetal lung tissues. Thus, the higher expression without obvious myc gene amplification was observed. The cell lines and tumors with the amplified myc always expressed their corresponding myc genes. The results suggested that higher levels of expression of the myc gene family may play a significant role in the oncogenesis of SCLC. Amplification and/or high levels of expression of c-myc were observed not only in variant type SCLC lines, but also in classic type lines. Thus, they were not necessarily associated with distinct biomarkers of SCLC lines.

Antigens, Surface↗
PubMed1988

Retinal toxicity of cyanoacrylate tissue adhesive in the rabbit.

N-butyl-2-cyanoacrylate tissue adhesive was injected into the preretinal space of rabbit eyes to study potential toxicity to the retina. Application of 3.3-10.0 ul of cyanoacrylate tissue adhesive showed localized but definite retinal toxicity. White halos appeared surrounding the preretinal cyanoacrylate immediately after injection with a gradual evolution of the white areas into pigmentary scars by 1 month. Histological examination confirmed severe focal necrosis of the retina. No identifiable distant toxic effects or electrophysiologic changes were observed during the 6-month follow-up period.

Animals↗