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E Hosoi

Publications and source records attributed to E Hosoi.

At least 19 recordsLinked to original sources
PubMed2001

Expression of the ryanodine receptor isoforms in immune cells.

Ryanodine receptor (RYR) is a Ca(2+) channel that mediates Ca(2+) release from intracellular stores. We have used RT-PCR analysis and examined its expression in primary peripheral mononuclear cells (PBMCs) and in 164 hemopoietic cell lines. In PBMCs, type 1 RYR (RYR1) was expressed in CD19(+) B lymphocytes, but less frequently in CD3(+) T lymphocytes and in CD14(+) monocytes. Type 2 RYR (RYR2) was mainly detected in CD3(+) T cells. Induction of RYR1 and/or RYR2 mRNA was found after treatment with stromal cell-derived factor 1, macrophage-inflammatory protein-1alpha (MIP1alpha) or TGF-beta. Type 3 RYR (RYR3) was not detected in PBMCs. Many hemopoietic cell lines expressed not only RYR1 or RYR2 but also RYR3. The expression of the isoforms was not associated with specific cell lineage. We showed that the RYR-stimulating agent 4-chloro-m-cresol (4CmC) induced Ca(2+) release and thereby confirmed functional expression of the RYR in the cell lines expressing RYR mRNA. Moreover, concordant induction of RYR mRNA with Ca(2+) channel function was found in Jurkat T cells. In untreated Jurkat T cells, 4CmC (>1 mM) had no effect on Ca(2+) release, whereas 4CmC (<400 microM) caused Ca(2+) release after the induction of RYR2 and RYR3 that occurred after treatment with stromal cell-derived factor 1, macrophage-inflammatory protein-1alpha, or TGF-beta. Our results demonstrate expression of all three isoforms of RYR mRNA in hemopoietic cells. Induction of RYRs in response to chemokines and TGF-beta suggests roles in regulating Ca(2+)-mediated cellular responses during the immune response.

Calcium↗
PubMed1998

Detection of histo-blood group ABO mRNA in human chronic myeloid leukemia cell lines using reverse transcription-polymerase chain reaction (RT-PCR).

ABH carbohydrate antigens are cell surface carbohydrates which occur in three allelic forms, namely A, B and O blood groups. It is unknown how the ABO blood group is expressed in hemopoietic stem cells. In an attempt to verify the ABO mRNA expression in hemopoietic precursor cells, mRNAs were isolated from human chronic myeloid leukemia (CML) cell lines which are believed to be at the most immature level of hemopoietic differentiation among hemopoietic malignancies. In particular, K-562 and KOPM-28 cells were used with the reverse transcription-polymerase chain reaction (RT-PCR) technique for amplifying ABO gene transcripts. The amplified ABO cDNAs from two cell lines were characterized by the digestion of Kpn-I restriction enzyme. The blood types were determined by polymerase chain reaction of the specific allele (PASA) method. Both of the human chronic myeloid leukemia cell lines expressed ABO mRNA. The quantity of ABO mRNA in the K-562 cell line is significantly higher than that of the KOPM-28 cell line. The ABO blood type of these two cell lines was type O. Because the CML cell lines are presumed to be at the immature stem cell level of hematopoietic cell differentiation and because it is believed that the cultured cell lines from hematologic malignancy reflect the characteristics of normal corresponding hemopoietic cells, the hemopoietic stem cells should express mRNA of the ABO blood group.

ABO Blood-Group System↗
PubMed1998

Effect of MDR antagonists on the cidal activity of vincristine for cells expressing MDR-1 is superior to those expressing MRP.

In an attempt to identify the target protein, P-GP or mrp, of each MDR antagonist, verapamyl (Ver), dipyridamole (Dip), or cyclosporin A (Cy-A), this study was designed to compare the activity of the three afore-mentioned drugs and to test their combined effect on the cidal activity of vincristine (VCR) in five types of wild and the corresponding VCR-resistant cultured cell lines from human leukemia and lymphoma. Three of the VCR-resistant cell lines are characterized by the overexpression of mdr-1, while two cell lines overexpress mrp. We found that all three antagonists additively to synergistically enhanced the cidal activity of VCR for the five wild-type and VCR-resistant cell lines in a dose dependent manner when used singly. Combinations consisting of a 20% inhibitory concentration (IC20) of VCR plus two antagonists also showed additive to synergistic effects on both wild and VCR-resistant cell lines. It is of interest that the combined effect of IC20 VCR plus MDR antagonists on the three VCR-resistant cell lines expressing mdr-1 was significantly superior to those of the two cell lines expressing the mrp gene. These results suggest that the combined effect of MDR antagonists work better than their single use and that the MDR antagonists work more efficiently in cells showing drug resistance through mdr-1 than in those utilizing mrp.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1997

Correlation between permeability-related glycoprotein expression and susceptibilty to oxygen radicals in vincristine-resistant hematologic cell lines.

This study was designed to test the correlation between the expression of permeability-related glycoprotein (P-GP) and susceptibility to oxygen radicals derived from the reaction of hypoxanthine (HX)-xanthine oxidase (XO) in wild type and vincristine (VCR)-resistant hematologic cell lines. A marked correlation between P-GP expression and susceptibility to oxygen radicals was found in VCR-resistant cells, while it was weak in wild cell lines. In contrast, there was neither correlation between sensitivity to VCR and oxygen radicals nor between sensitivity to VCR and P-GP expression in both wild type and VCR-resistant cells. No correlation between sensitivity to adriamycin or oxygen radicals and P-GP expression were observed in both cells tested. These results may suggest a new mechanism of drug resistance in cells expressing P-GP.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1997

Immunoreactive growth hormone-releasing hormone (IR-GHRH) in the feto-placental circulation and differential effects of L-dopa, L-arginine and somatostatin-14 on the plasma levels of IR-GHRH in normal adults.

The relation of the physiological releases of growth hormone-releasing hormone (GHRH) and growth hormone (GH) into the circulation in various conditions was investigated using a sensitive and specific radioimmunoassay for plasma GHRH. The mean fasting plasma level of immunoreactive (IR)-GHRH in 72 normal adults was 10.3 +/- 0.5 (mean +/- SEM) pg/ml and there was no significant sex difference in the level. The concentrations of IR-GHRH in plasma from the umbilical artery and umbilical vein were 107.3 +/- 20.5 pg/ml and 33.6 +/- 3.8 pg/ml, respectively, and a marked arterio-venous gradient was observed in all 12 individuals examined. The plasma level of IR-GHRH in the maternal vein was significantly lower than that in the cord blood, but was similar to that in non-pregnant women. In normal adults, although there was no apparent fluctuation in the level of plasma IR-GHRH or of plasma GH during bed rest, a significant increase of plasma IR-GHRH was detected followed by, or synchronized with the surge of plasma GH after oral administration of L-dopa. In contrast, on L-arginine infusion, no proportional elevation of plasma IR-GHRH with increase in plasma GH was observed. During and after intravenous infusion of somatostatin, the circulating IR-GHRH level did not increase, but on stopping the infusion there was an immediate and marked rebound surge of GH. We conclude that 1) the elevated IR-GHRH in the cord blood plasma originates from the fetus and may have a primary role in enhancing secretion of GH which promotes growth in early human life, and 2) the participations of GHRH in the mechanisms of GH secretion seen after administrations of L-dopa, L-arginine and somatostatin are different.

Adult↗
PubMed1997

Secretory profile of immunoreactive growth hormone-releasing hormone (IR-GHRH) during sleep in man and its clinical value.

To clarify the role of growth hormone-releasing hormone (GHRH) in the regulation of the episodic growth hormone (GH) secretion which is known to occur constantly in the initial slow wave stage of nocturnal sleep in man, we studied the relation between the secretions of plasma immunoreactive(IR)-GHRH and GH while recording electroencephalograms. In subjects who showed a normal sleep pattern, the plasma IR-GHRH level increased 3- to 4-fold just before the surge of plasma GH, suggesting that GH release in the initial slow wave stage of sleep is mainly mediated by GHRH. However, when there was an apparent GH surge just before the onset of sleep, the magnitude of the GH response associated with the initial slow wave stage tended to be blunted, even when sufficient IR-GHRH was released. We also observed no appreciable fluctuations of plasma IR-GHRH during nocturnal sleep in a patient diagnosed as having GH-deficient dwarfism, suggesting the primary lesion was on the hypothalamus level, not the pituitary, in such a patient. In a case of multiple endocrine neoplasia (MEN) type I with an ectopic (GHRH-producing pancreatic tumor, no remarkable elevation of plasma IR-GHRH was detected in the initial slow wave stage of nocturnal sleep. We conclude that the present study is significant not only in demonstrating the physiology of GHRH release, but also in establishing a safe, reliable and practical test for routine clinical use to investigate intrinsic ability to release GHRH and the primary lesions in patients with disorders of GH secretion.

Acromegaly↗
PubMed1997

[Genetic analyses of the ABO blood groups and application of the clinical laboratories].

Gene technology using polymerase chain reaction (PCR) has markedly advanced in recent year and has been introduced in clinical laboratories. In this paper, the genotypes of genomic DNAs of subjects with cisAB blood group were analysed using three methods, polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP), and the PCR-direct sequencing method, and directly determined using the polymerase chain reaction (PCR) amplification of specific alleles (PASA)-method. The differences among the methods were as follows, PCR-RFLP and PCR-direct sequencing method require 2-step procedures, and are complicated for clinical laboratories. The PASA method is based on the fact that PCR amplification occurs only when the 3' endbase of the primer is matched to sites of the nucleotide substitution of ABO allelic cDNA. Three of five regions of allelic DNAs were co-amplified in a single PCR (multiplex-PCR) in this study. ABO and cisAB blood group genotypes were directly determined, based on the molecular size of allele-specific amplification products. The PASA method requires only about 4 hours from starting PCR to results, making it rapid, simple and useful for detecting the genotype of ABO and cisAB blood groups in comparison with PCR-RFLP and the direct sequencing methods and will allow this procedure to be very versatile and widely used throughout the research and clinical diagnostic communities. The analyses of the nucleotide sequence at nucleotides No. 261, 526, 703, 796 and 803 in 3 major subjects in the cisAB blood group (cisA2B3, cisA1B3 and cisA2B) revealed chimeric structures of the A allele and B allele on the same gene.

ABO Blood-Group System↗
PubMed1996

Takayasu's arteritis associated with antiphospholipid antibodies. Report of two cases.

The authors describe 2 patients with Takayasu's arteritis in whom lupus anticoagulant was positive and the titer of anticardiolipin antibody was elevated. One patient developed diffusely stenotic and occlusive changes in the multiple larger arteries. Histology of the small-sized arteries in another patient showed occlusive vasculitis without thrombosis, in addition to the findings in large-sized arteries compatible with Takayasu's disease. These findings are uncommon in Takayasu's arteritis. These findings suggest that antiphospholipid antibodies may have contributed to the pathogenesis of the extensive vasculopathy and may have triggered vasculitis in these patients.

Adult↗
PubMed1996

[Direct determination of ABO and cisAB blood group genotypes using polymerase chain reaction amplification of specific alleles (PASA)--method].

The genotypes of genomic DNAs of 20 normal subjects with ABO blood group and 12 subjects with cisAB blood group were directly determined using polymerase chain reaction (PCR) amplification of specific alleles (PASA)-method. This method is based on the fact that PCR amplification occurs only when the 3' endbase of the primer is matched to the nucleotide of No. 261, 526, 796 or 803 of ABO allelic cDNA. And three of five regions of allelic DNAs are co-amplified in a single PCR (multiplex-PCR) in this study. ABO and cisAB blood group genotypes are directly determined, based on the molecular size of allele specific amplification products that contain 261, 526, 796 and 803 nucleotide (the sites of amino acid substitutions). The method requires only about 4 hours from starting up of PCR to the results, so it is rapid, simple and useful for detecting the genotype of ABO and cisAB blood groups.

ABO Blood-Group System↗
PubMed1995

Increased serum IgE level and interleukin-4 release from cultured lymphocytes from a patient with adult onset Still's disease.

OBJECTIVE: To evaluate the relationship between high serum levels of IgE and the release of interleukin-4 (IL-4) from cultured lymphocytes of a patient with adult onset Still's disease. METHODS: IL-4 concentrations in plasma and culture from inactivated peripheral blood mononuclear cells were assessed by enzyme immunoassay during febrile episodes and remission. RESULTS: A high level of IL-4 was detected by enzyme immunoassay in the peripheral blood mononuclear cells cultured from the patient. These seemed to correspond with a febrile episode and a high serum IgE concentration. CONCLUSION: Increased serum IgE concentrations during a febrile episode are rare in patients with adult onset Still's disease, but the relationship between the high levels of serum IgE and IL-4 in cultured lymphocytes may provide clues to pathogenesis of the condition.

Adult↗
PubMed1995

Two different pituitary adenomas in a patient with multiple endocrine neoplasia type 1 associated with growth hormone-releasing hormone-producing pancreatic tumor: clinical and genetic features.

The clinical and genetic features of a 43-year-old male patient with multiple endocrine neoplasia type 1 were reported. He developed hyperparathyroidism, a GHRH-producing pancreatic tumor, and acromegaly between 1980 and 1983. Because his pituitary gland increased in size even after resecting the GHRH-producing pancreatic tumor, transsphenoidal hypophysectomy was performed six years later. The pituitary contained two histologically-different adenomas composed of somatotroph cells and null cells. Genetic analyses revealed loss of heterozygosity on chromosome 11 in common in the pituitary adenomas, the pancreatic endocrine tumors, and a parathyroid hyperplasia. On the other hand, mutations of ras, p53, Gs alpha, and Gi2 alpha genes were not found in these tumors. The loss of the tumor suppressor gene on chromosome 11q12-13 was involved in the formation of two pituitary adenomas, two pancreatic endocrine functioning tumors, and a parathyroid hyperplasia in this patient, but the tumorigenic factors in the specific endocrine organs remain to be studied.

Acromegaly↗
PubMed1995

[Genetic analysis of the genotype of ABO blood group with the DNA from a hair].

The genotype of the hair genomic DNA from 14 subjects with the ABO blood group was determined using the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. The amino acid substitutions of codon 87 and 176 of ABO allelic cDNAs were analyzed to distinguish A, B, and O alleles by restriction enzyme digestion. To identify codon 87, the 249bp DNA fragment was amplified by PCR and digested with Kpn I. To identify codon 176, the 285bp DNA fragment was amplified by PCR and digested with Ban I. The genotype of the 14 ABO type-known subjects could be identified by the analysis of the digested DNA fragments. These findings indicate the usefulness of the PCR-RFLP method for determining the ABO genotype with the DNA from only one hair.

ABO Blood-Group System↗
PubMed1994

Familial occurrence of two patients with malignant rheumatoid arthritis.

In Japan, patients with rheumatoid arthritis associated with severe extra-articular manifestations due to vasculitis are diagnosed as having malignant rheumatoid arthritis. We report the occurrence of two cases of malignant rheumatoid arthritis in a Japanese family. Both patients, a father and son, expressed HLA-DR4 (Dw15), and were infected with Epstein-Barr virus. Moreover, the father developed malignant rheumatoid arthritis during reactivation of the Epstein-Barr virus. An unaffected male family member with the same HLA haplotypes was not infected by the virus. The possible role of the virus infection in the pathogenesis of malignant rheumatoid arthritis in a genetically susceptible family is discussed.

Adult↗
PubMed1993

Demonstration of biological activity of a growth hormone-releasing hormone-like substance produced by a pheochromocytoma.

The biological characteristics of a growth hormone-releasing hormone (GHRH)-like substance produced by a pheochromocytoma were studied. Analysis by gel filtration chromatography combined with the use of two distinct GHRH antisera that recognize the N- and C-termini of authentic GHRH(1-44)NH2 indicated molecular heterogeneity of the immunoreactive GHRH in the tumor extract, but a component corresponding to GHRH(1-44)NH2 was the predominant form. The biological activity of this immunoreactive component was assessed in vitro by measuring its ability to induce growth hormone release from dispersed rat anterior pituitary cells. At concentrations of 0.125-2.0 nmol/l, the test materials induced a dose-related increase in growth hormone release from the cells into the incubation medium (range 992 +/- 68-1872 +/- 32 ng.1.7 x 10(5) cells-1 x 3 h-1), similar to that observed with synthetic GHRH(1-44)NH2. (control value 640 +/- 30 ng.1.7 x 10(5) cells-1 x 3 h-1). This suggests that immunoreactive GHRH in the tumor has almost the same biological activity as the synthetic product and that a combination of pheochromocytoma and acromegaly is not always fortuitous because both diseases may be caused by a single neoplasm.

Adrenal Gland Neoplasms↗