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Biomedical subjects

H Nishio

Publications and source records attributed to H Nishio.

At least 91 records · Page 5Linked to original sources
PubMed1998

Nonadrenergic, noncholinergic relaxation mediated by nitric oxide with concomitant change in Ca2+ level in rectal circular muscle of rats.

The mediators of nonadrenergic, noncholinergic (NANC) relaxation of the circular muscle of rat rectum were examined in vitro. In the circular muscle of rat rectum, NG-nitro-L-arginine (L-NOARG) at 10 microM did not affect electrical field stimulation-induced relaxation but at 100 microM it inhibited electrical field stimulation-induced relaxation by about 75% and 1-mM L-arginine reversed the inhibition. Exogenous nitric oxide (NO) (1-10 microM) concentration dependently relaxed the circular muscle. Electrical field stimulation increased the cyclic GMP content of the circular muscle to about twice its resting level. L-NOARG, even at 10 microM, completely inhibited the electrical field stimulation-induced elevation of cyclic GMP content. However, L-arginine at 1 mM did not reverse the inhibition in cyclic GMP content. Inhibitory junction potentials (i.j.ps) induced by electrical field stimulation in the circular muscle cells were not affected by L-NOARG, 100 microM. Apamin ( < or = microM) did not affect the electrical field stimulation-induced relaxation, but almost completely inhibited electrical field stimulation-induced i.j.ps. NO (0.3-10 microM) induced relaxation of the circular muscle with a concomitant decrease in intracellular Ca2+ level ([Ca2+]i). Abundant immunoreactivity of NO synthase was found in the circular muscle layer, in addition to myenteric and submucosal plexus. The results suggest that NO induces NANC relaxation with a concomitant change in [Ca2+]i in the circular muscle of rat rectum. However, the involvement of changes in cyclic GMP level and in membrane potentials in the mechanism was not shown in the present experimental conditions.

Animals↗
PubMed1998

Generation of a monoclonal antibody that induces apoptosis of hematopoietic cells.

Here, we developed anti-murine myeloid cell (NFS-60 cell) monoclonal antibodies in order to characterize the further mechanism of cell-to-cell interaction between the stromal cells and the hematopoietic progenitor cells. The established antibody, designated mAb UNF, inhibited proliferation of NFS-60 cells and induced apoptosis. Incubation of NFS-60 cells with mAb UNF initiated the cell aggregation within 3 hours. This phenomena did not require newly synthesized proteins, since the pretreatment of 1 mM cycloheximide failed to prevent the agglutination. Fifty-eight percent of mouse hematopoietic stem cells, Lin-, c-Kit+, Sca-1+ bone marrow cells, were shown to express UNF antigen. The glycolipid prepared from NFS-60 cells was specifically immunostained by mAb UNF.

Animals↗
PubMed1998

Models of lineage switching in hematopoietic development: a new myeloid-committed eosinophil cell line (YJ) demonstrates trilineage potential.

A new human leukemia cell line with an eosinophilic phenotype, designated YJ, was established from the peripheral blood cells of a patient with chronic myelomonocytic leukemia (CMMoL) with eosinophilia. When cultured in RPMI 1640 medium containing 10% fetal bovine serum, most YJ cells were myeloblastoid with a small number of the cells having eosinophilic granules. Cell surface markers in the YJ cells were positive for CD33 and were negative for CD34, CD16 and CD23. The eosinophilic characteristics of YJ cells were confirmed by histochemical staining with Fast-Green/Neutral-Red and by the expression of mRNAs for eosinophil-associated granule proteins, eosinophil cationic protein (ECP), eosinophil-derived neurotoxin (EDN), eosinophil peroxidase (EPO), and major basic protein (MBP), and for the Charcot-Leyden crystal (CLC) protein. The YJ cells could be induced towards monocytic differentiation by stimulation with phorbol 12-myristate 13-acetate (PMA). The monocytic characteristics of YJ cells treated with PMA were confirmed by morphological analysis with alpha-naphthyl butyrate esterase staining, by CD14 expression, and by increased expression of Egr-1 mRNA. Furthermore, YJ cells could be differentiated towards the neutrophil lineage by stimulation with all-trans retinoic acid (RA). YJ cells treated in vitro with 2 microM RA differentiated into metamyelocytes and band neutrophils, and increased the number of nitroblue tetrazolium (NBT)-positive cells and increased gp91phox mRNA expression. Thus, the YJ cell line exhibited eosinophilic characteristics, but was able to differentiate to the monocytic or neutrophilic lineages in response to PMA or RA, respectively. The expression of genes for transcription factors involved in myeloid differentiation was evaluated by Northern blot analysis. Increased expression of Egr-1 was observed with macrophage differentiation. In contrast, increased expressions of C/EBPbeta and MZF-1 mRNA occurred with neutrophilic differentiation. The YJ cell line should be useful for elucidating the molecular mechanisms governing lineage switching from the eosinophil to monocytic or neutrophil lineages.

Antigens, Surface↗
PubMed1998

Characterization of TEK receptor tyrosine kinase and its ligands, Angiopoietins, in human hematopoietic progenitor cells.

TEK, or TIE-2, is a receptor tyrosine kinase (RTK) that is known as a functioning molecule of vascular endothelial cells. TEK comprises a subfamily of RTK with TIE, and these two receptors play critical roles in vascular maturation, maintenance of integrity and remodeling. We generated mAb against the extracellular domain of human TEK protein to elucidate its expression pattern in human hematopoietic cells. Flow cytometric analysis of bone marrow cells revealed that TEK was expressed in 27% of CD34+ cells, 20% of c-KIT+ cells and 26% of CD34+CD38- cells, indicating that TEK is expressed in a subset of primitive hematopoietic stem cells (HSC). TEK was also expressed in 20% of CD19+ B lymphocytes but not in other lineage-committed cells. Progenitor assays in methylcellulose culture showed that CD34+TEK+ cells formed significantly less BFU-E and CFU-Mix than CD34+TEK- cells, but there was no difference in the number of CFU-GM between these two populations. Two recently identified TEK ligands, termed Angiopoietin-1 and -2, bound to TEK with similar affinities, and Angiopoietin-1 effectively induced TEK phosphorylation in hematopoietic cells. Angiopoietin-2 also induced a low level of TEK phosphorylation and weakened the phosphorylation induced by Angiopoietin-1, suggestive of an elaborate regulator of the TEK-TEK ligand signaling pathway. Although neither ligands affected the proliferation of TEK-transfected hematopoietic cells or the colony formation of CD34+TEK+ bone marrow cells, both promoted the adhesion of TEK-transfected hematopoietic cells to a collagen matrix or a layer of bone marrow stromal cells. These findings indicate that the TEK-TEK ligand signaling pathway is regulated in a refined manner and is involved in hematopoietic cell-microenvironment interaction.

Angiopoietin-1↗
PubMed1998

Chemical synthesis of dendrotoxin-I: revision of the reported structure.

Dendrotoxin I (DTX-I) is a 60-residue peptide from the venom of the black mamba snake Dendroaspis polylepis, which binds to neuronal K+ channels. The structure reported previously for DTX-I was synthesized for the first time by a solution procedure. The synthetic product was confirmed to have the correct primary and disulfide structure determined by peptide mapping, sequence analysis and mass measurements. Comparison of synthetic DTX-I with the natural one by high-performance liquid chromatography and capillary zone electrophoresis, as well as by sequence analysis, revealed that the Asn residue at position 12 in the synthetic peptide was Asp in the natural product. Synthesis of DTX-I with Asp at position 12 gave a peptide identical with the natural product in all aspects. NMR analysis of synthetic [Asn12]- and [Asp12]-DTX-I also supported our findings that the Asn residue at position 12 in the DTX-I molecule should be revised as Asp. [Asn12]- and [Asp12]-DTX-I had very similar binding affinities when tested against radiolabeled dendrotoxin binding to rat brain synaptosomal membranes.

Amino Acid Sequence↗
PubMed1998

The inhibitory effect of glabridin from licorice extracts on melanogenesis and inflammation.

Glabridin is the main ingredient in hydrophobic fraction of licorice extract affecting on skins. In this study, we investigated inhibitory effects of glabridin on melanogenesis and inflammation using cultured B16 murine melanoma cells and guinea pig skins. The results indicated that glabridin inhibits tyrosinase activity of these cells at concentrations of 0.1 to 1.0 microg/ml and had no detectable effect on their DNA synthesis. Combined analysis of SDS-polyacrylamide gel electrophoresis and DOPA staining on the large granule fraction of these cells disclosed that glabridin decreased specifically the activities of T1 and T3 tyrosinase isozymes. It was also shown that UVB-induced pigmentation and erythema in the skins of guinea pigs were inhibited by topical applications of 0.5% glabridin. Anti-inflammatory effects of glabridin in vitro were also shown by its inhibition of superoxide anion productions and cyclooxygenase activities. These data indicated that glabridin is a unique compound possessing more than one function; not only the inhibition of melanogenesis but also the inhibition of inflammation in the skins. By replacing each of hydroxyl groups of glabridin with others, it was revealed that the inhibitory effect of 2'-O-ethyl glabridin was significantly stronger than that of 4'-O-ethyl-glabridin on melanin synthesis in cultured B16 cells at the concentration of 1.0 mg/ml. With replacement of both of two hydroxyl groups, the inhibitory effect was totally lost. Based on these data, we concluded that two hydroxyl groups of glabridin are important for the inhibition of melanin synthesis and that the hydroxyl group at the 4' position of this compound is more closely related to melanin synthesis.

Administration, Topical↗
PubMed1998

Relationship between muscarinic autoinhibition and the inhibitory effect of morphine on acetylcholine release from myenteric plexus of guinea pig ileum.

The relationship between muscarinic autoinhibition and the inhibitory effect of morphine on acetylcholine (ACh) release was investigated in a longitudinal muscle with myenteric plexus (LMMP) preparation of guinea pig ileum. Morphine (10 microM) inhibited spontaneous and evoked ACh release by electrical field stimulation (EFS) at 1 Hz but not at 10 Hz. Atropine (1 microM) did not affect the resting ACh release, but it significantly increased EFS-evoked release, suggesting activation of muscarinic autoreceptors by ACh released during EFS. Only when the autoinhibition was weakened by atropine, morphine exhibited an inhibitory effect on the EFS-evoked release at 10 Hz. Bethanechol (300 microM) inhibited the EFS-evoked release at 1 Hz but not 10 Hz, suggesting that muscarinic autoreceptors are partially or almost fully activated at 1 or 10 Hz stimulation, respectively. After bethanechol treatment, morphine did not exhibit its inhibitory effect on the EFS-evoked release at 1 Hz. Naloxone (1 microM) increased spontaneous and EFS-evoked ACh release at 1 Hz but not at 10 Hz. Following treatment with atropine, naloxone also increased ACh release at 10-Hz stimulation. These results suggest that morphine and an endogenous opioid inhibit ACh release from LMMP preparations when muscarinic autoinhibition mechanism does not fully work. This inhibitory effect of morphine is discussed in relation to the calcium sensitivity of the preparations in ACh release.

Acetylcholine↗
PubMed1998

Relationship between inhibitory effect of endogenous opioid via mu-receptors and muscarinic autoinhibition in acetylcholine release from myenteric plexus of guinea pig ileum.

Relationship between activation of opioid receptors and muscarinic autoinhibition in acetylcholine (ACh) release from the myenteric plexus was studied in longitudinal muscle myenteric plexus (LMMP) preparations of guinea pig ileum. A mu-receptor agonist, [D-Ala2, N-Me-Phe4, Gly5-ol] enkephalin (DAMGO), at a concentration of 1 microM inhibited the ACh release evoked by electrical field stimulation (EFS) at 1 Hz but not at 10 Hz. After the muscarinic autoreceptors were blocked with atropine (1 microM), DAMGO inhibited EFS-evoked ACh release also at 10 Hz. After the autoreceptors were potently activated with muscarine (200 microM), the inhibitory effect of DAMGO at 1 Hz was abolished. A kappa-receptor agonist, U-50,488, at 1 microM inhibited the EFS-evoked ACh release both at 1 and 10 Hz. U-50,488 inhibited ACh release regardless of the presence of atropine or muscarine. A delta-agonist, enkephalin [D-PEN2.5] (PDPDE), did not show any significant effect. On the other hand, a selective mu-receptor antagonist, cyprodime, increased ACh release evoked by EFS at 1 Hz, but not at 10 Hz. After the autoreceptors were blocked, cyprodime increased EFS-evoked ACh release also at 10 Hz. The selective kappa-receptor antagonist, nor-binaltorphimine, did not affect ACh release in the absence or presence of atropine. The results suggest that endogenous opioid(s) inhibits ACh release by activating mu-, but not kappa- and delta-receptors in the LMMP of guinea pig ileum and that the inhibitory effect of endogenous opioid(s) in the ACh release is important when muscarinic autoinhibition mechanism does not fully work.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed1998

Decrease in participation of nitric oxide in nonadrenergic, noncholinergic relaxation of rat intestine with age.

Participation of nitric oxide in the electrical field stimulation-induced nonadrenergic, noncholinergic (NANC) relaxation in various intestinal regions was studied in 2- to 50-week-old Wistar rats. In the jejunum of 2-week-old rats, the extent of the nitric oxide-mediated component of the relaxation of longitudinal muscle was approximately 60-70%, whereas the component was 40-50% in 4-week-old rats and was absent in 8- and 50-week-old rats. Thus, nitric oxide seems to be the most important mediator at young ages but its significance is lost with age. The same tendency as that in the jejunum was also shown in longitudinal muscle of the ileum, proximal and distal colon, and rectum. The tendency was also shown in the circular muscle of the rectum. Sensitivity of the longitudinal muscle of the jejunum and proximal colon to exogenously added nitric oxide was high in younger rats. Immunoreactive structures for nitric oxide synthase were observed in the circular muscle layer of the rectum. The population of the structures was denser in 4-week-old than that in 50-week-old. The results suggest that NANC relaxation in every region of the intestine at 2-week-old is almost solely mediated by nitric oxide, and its significance as an inhibitory mediator gradually or rapidly decreases with age.

Adrenergic Agents↗
PubMed1998

Inhibitory effect of endomorphin-1 and -2 on acetylcholine release from myenteric plexus of guinea pig ileum.

Endomorphin-1 and -2, putative endogenous ligands for the mu-opioid receptor, inhibited acetylcholine (ACh) release evoked by electrical field stimulation (EFS) at 1 Hz, which partially activates muscarinic autoreceptors, but not at 10 Hz, which fully activates muscarinic autoreceptors, in longitudinal muscle with the myenteric plexus (LMMP) preparations of guinea pig ileum. After blockade of autoinhibition by atropine, the peptides also inhibited EFS-evoked ACh release at 10 Hz. The inhibitory effects on ACh release were abolished by the mu-opioid antagonist cyprodime. These results suggest that endomorphin-1 and -2 inhibit ACh release from LMMP preparations of guinea pig ileum and that the mechanism of the inhibition must have a component in common with muscarinic autoinhibition.

Acetylcholine↗
PubMed1998

Estimation of age from the femur of Japanese cadavers.

This study was designed to estimate the age at the death of cadavers by histomorphometry of the femur. Samples from 72 Japanese males from 43 days to 92 years old and 26 females from 2 to 88 years old were used. The thickness of sections was adjusted to 50-70 microns by grinding with sandpaper. The sections were not any decalcified. They were stained with Villanueva's bone staining powder and thionin dye. The microradiographs of the sections were obtained by a soft x-ray apparatus. The area, length, width, and perimeter of the perfect osteon and haversian canal were measured. The type II osteon number, osteon fragment number, and area of triangle were also determined. These parameters were examined by an image analyzer. The parameters of the osteon showed a high correlation coefficient with age (magnitude of r > or = 0.77), whereas those of the haversian canal were low (magnitude of r < or = 0.11). All parameters were subjected to multiple regression analysis for producing a multiple regression equation of age estimation. For the stepwise selection method, the perimeter of osteon, length of the haversian canal, and osteon fragment number were selected for the equation. Their multiple r2 and standard error of estimation were 0.8874 and 6.39, respectively. For the forward selection method, in addition to the above items, three parameters, the length of osteon, area of triangle, and width of osteon, were selected. Their multiple r2 and standard error of estimation were 0.9484 and 4.884, respectively. Bone staining was useful to clarify the demarcation between osteon and fragment, leading to increased accuracy of age estimation. However, precisely estimating age for the entire range from birth to 90 years was difficult.

Adult↗
PubMed1998

A novel single basepair insertion in exon 6 of the Bruton's tyrosine kinase (Btk) gene from a Japanese X-linked agammaglobulinemia patient with growth hormone insufficiency.

A novel insertion mutation in exon 6 of the Btk gene was detected in a 17 year-old XLA patient with GH insufficiency. We synthesized cDNA from leukocyte total RNA and amplified every region of the Btk-coding sequence. Sequencing of cDNA fragments revealed a single basepair insertion mutation at codon 157 in exon 6 (CAG-->CAAG) which leads to premature termination at codon 193 in exon 7. To confirm the results, we also performed a PCR-DdeI digestion analysis using leukocyte genomic DNA. The PCR product from the patient's genomic DNA was uncleaved with DdeI, as expected. PCR-DdeI digestion analysis of the family members showed that the mother and elder sister were carriers with the mutation and that the younger sister did not carry the mutation.

Adolescent↗
PubMed1998

[Application of ultrasound method for hemorrhagic digestive disease].

Ultrasonography for the digestive diseases are consisted of abdominal ultrasonography (US), endoscopic ultrasonography (EUS) and color Doppler endoscopic ultrasonography (CDEUS). These play a supplementary role in comparison with the roentgenography and endoscopy. The information of the ultrasonography is different from these examinations. By US the collateral shunts of esophago-gastric varices are observed. EUS is useful for diagnosis of the properties of esophago-gastric varices and judgement of effects of treatment for these varices, gastric ulcer and vessels in ulcer base and hemorrhagic bowel diseases. CDEUS can show blood streams of esophago-gastric varices and hemorrhagic ulcer.

Duodenal Ulcer↗
PubMed1998

[Genetic analysis including predictive DNA testing in a Japanese family with dentatorubral-pallidoluysian atrophy].

Dentatorubral-pallidoluysian atrophy (DRPLA) is a neurodegenerative disease showing autosomal dominant inheritance, which is associated with a specific trinucleotide repeat expansion in the DRPLA gene. We performed DNA analysis of two affected and one non-affected individuals of a Japanese family with DRPLA. The proband (case 1) developed seizures at age 17, and these gradually evolved to intractable myoclonic epilepsy. His father (case 2) had manifested gait disturbance since the age of 40, which was followed by progressive dementia. DNA analysis disclosed that these patients had an expanded CAG repeat in the DRPLA gene, which confirmed the diagnosis. The brother of case 1, who was asymptomatic, expressed a desire to undergo predictive DNA testing for DRPLA. We discussed the ethical and social issues of this predictive testing, and decided to carry out the testing after obtaining informed consent from him and his wife. The test revealed no expanded allele, thus proving that he would not develop DRPLA, and relieving him of his fears. Our results suggest that predictive testing improves the psychological well-being of non-affected individuals in DRPLA families.

Adult↗
PubMed1998

Splicing error due to a splice acceptor site mutation in the ALD gene identified in a Japanese childhood cerebral adrenoleukodystrophy case.

X-linked adrenoleukodystrophy (ALD) is characterised by progressive multifocal demyelination of central nervous system and adrenocortical insufficiency. This disorder has been also associated with mutations in the ALD gene, encoding an ATP-binding transporter which is located in the peroxisomal membrane. Defect of the gene may lead to impaired peroxisomal beta-oxidation and increase of serum and tissue very long chain fatty acids (VLCFAs). Here we report the results of analysis of the ALD gene in a Japanese patient with childhood cerebral ALD. In our patient, by sequencing of the ALD cDNA, an 8 bp insertion (ACCCCCAG) was detected at the start of exon 9, which corresponded to nucleotides from position -1 to -8 of the 3' splice acceptor site of intron 8. Sequencing of genomic DNA showed a single nucleotide substitution at position-10 of the 3' splice acceptor site of intron 8 replacing a G with an A which activated a cryptic splice acceptor site. It is concluded that a splicing error was induced by a point mutation that created a novel splice acceptor site. This insertion created a nonsense codon downstream, producing a truncated ALD protein. His mother and younger sister with increased VLCFA ratios were heterozygotes of normal and mutant ALD genes.

ATP-Binding Cassette Transporters↗