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Biomedical subjects

N Harada

Publications and source records attributed to N Harada.

At least 433 records · Page 24Linked to original sources
PubMed1993

The rate of oxygen release from single sinusoid of rat liver, determined by microspectroscopy.

The rate of oxygen release from single hepatic sinusoid of rat was determined. A scanning spectrophotometer, equipped with a grating and two photoncounters, was connected to a microscope with light-guides, and absorption spectra (450-650 nm) were obtained simultaneously at two microspots (10 microns diameter) on single sinusoid. The concentration ([Hb]) and oxygen saturation (SO2) of hemoglobin were calculated from the spectra. Reference transmittance was obtained at neighbouring hepatocytes. The erythrocyte velocity was measured by dual-spots cross-correlation method using two photomultipliers connected to the microscope with two light-guides. The gradient in SO2 was observed along each sinusoid, due to oxygen release from flowing erythrocytes to hepatocytes. The rate of oxygen release per unit surface area was 0.24 +/- 0.14(n = 14)nmoles O2/cm2/sec, which was calculated from [Hb], difference in SO2 between the spots at up- and down-stream, erythrocyte velocity, two spot's distance and sinusoidal diameter. The rates of O2 release depended on sinusoidal diameter and sinusoidal blood flow.

Animals↗
PubMed1993

Ring chromosome 15 involving deletion of the insulin-like growth factor 1 receptor gene in a patient with features of Silver-Russell syndrome.

An 11-year-old girl with de novo r(15) (p12q26.3) with a clinical diagnosis of Silver-Russell syndrome (SRS) is presented. She had prenatal and postnatal growth deficiency with a severe short stature, peculiar facies characterized by a triangular face, a pinched nose with anteverted nostrils and down-turned corners of the mouth, bilateral clinodactyly of the fifth fingers, café-au-lait nevi, mental retardation, and a high level of serum follicular stimulating hormone. Southern blot analysis and chromosome fluorescence in situ hybridization revealed a deletion of the insulin-like growth factor 1 receptor gene (IGF1R) in the patient, the result indicating that IGF1R is assigned to 15q26.3. The deleted segment in our patient and comparisons with those of other reported cases of 15q-suggest that one of the putative SRS loci is at 15q26.3.

Abnormalities, Multiple↗
PubMed1993

Prevention, clinical, and pathophysiological research on vibration syndrome.

In the 1950s, introduction of portable power tools into the production process of many industries began on a large scale around the world and resulted in many cases of occupational vibration syndrome after the 1960s. There was an urgent need to undertake preventive steps, medical assessment and therapy throughout the world. At the end of 1964, our investigation began in Japanese national forests, and then in mining and stone quarries. Our research and efforts resulted in a comprehensive system for prevention of vibration syndrome in the Japanese national forest industry. It has presented a good model of prevention for other industries in Japan. Clinical and pathophysiological research on vibration syndrome in the 1960s and 1970s clarified disturbances of the peripheral circulatory, nervous, and musculoskeletal systems. From the mid-1970s, neurophysiological, neurochemical, and clinical research on vibration syndrome in relation to the autonomic nervous system developed. Our studies contributed to the advancement of research in this field. More in-depth study is needed to determine the role of the autonomic nervous system in vibration syndrome.

Humans↗
PubMed1993

EC syndrome in a girl with paracentric inversion (7)(q22.1;q36.3).

Ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome associated with a paracentric inversion of chromosome 7 in a 2-year-old Japanese girl is reported. She had sparse and light-brown hair, bilateral cleft lip and palate, fused lower incisors, a pigmented skin lesion at the neck, accessory nipples, limited extension of elbow joints and bilateral ectrodactyly of hands and feet. Cytogenetic studies demonstrated a balanced inv(7)(q22.1;q36.3) in the patient and her father. The association of EEC syndrome and inv(7) in the patient suggested a putative locus of the EEC syndrome gene either at 7q22.1 or 7q36.3, although a coincidental occurrence of the two conditions is an alternative explanation. A comparison with reported karyotypes in patients with EEC or isolated ectrodactyly favoured 7q22.1 as the locus. A normal phenotype of the father in our family might reflect reduced penetrance of the EEC syndrome or, possibly, reduced expression of a maternally-derived allele of the EEC syndrome gene through a genomic imprinting mechanism.

Abnormalities, Multiple↗
PubMed1993

Development of a resource-based patient classification scheme for rehabilitation.

Efforts are currently underway to develop a prospective payment system for inpatient medical rehabilitation. In this study, a clinically based, condition-specific patient classification scheme was developed that includes 33 patient groupings, referred to as Functional Related Groups (FRGs). Each FRG is comprised of patients with similar clinical characteristics and resource use, as measured by length of stay. From a policy perspective, the FRGs minimize the adverse incentives that may develop in the selection of patients for admission to the rehabilitation facility. The FRGs, therefore, may be used as a basis in the development of a prospective reimbursement system for rehabilitation services.

Adult↗
PubMed1993

[Idiopathic interstitial pneumonitis possibly associated with chronic graft-versus-host disease].

We described two cases of idiopathic interstitial pneumonitis (IP) after allogeneic bone marrow transplantation (BMT), who were successfully treated with prednisolone (PSL). A 40-year-old male with AML (M3) in the first remission (case 1) and a 36-year-old male with CML in chronic phase (case 2) were treated with BMT from HLA genotypically identical female siblings. Both patients were conditioned with busulfan (16mg/kg) and cyclophosphamide (120mg/kg), and given a combination of cyclosporin A and methotrexate to prevent acute GVHD (aGVHD). Engraftment of donor marrow was documented in both cases. Grade I of aGVHE developed in case 1 and no aGVHD in case 2. Both patients had clinical manifestations of chronic GVHD (cGVHD), which were followed by dyspnea and cough without fever 120 days (case 1) or 100 days (case 2) after BMT. Abnormal lung function tests and radiographic infiltrates indicated that patients developed IP, but causative microorganisms could not be detected in the bronchoalveolar lavage (BAL) specimens. Subjective symptoms disappeared in a few days after administering PSL (1mg/kg/day). Laboratory data also improved thereafter. These observations, including the development of radiographic infiltrates along with clinical manifestations of cGVHD, absence of febrile episodes, absence of causative microorganisms in the BAL specimens, and effectiveness of immunosuppressive drugs, suggested that idiopathic IP observed in our cases might be a manifestation of cGVHD.

Adult↗
PubMed1992

A unique aromatase (P-450AROM) mRNA formed by alternative use of tissue-specific exons 1 in human skin fibroblasts.

Aromatase mRNA in human skin fibroblasts was greatly increased in the presence of dexamethasone. Aromatase cDNA was prepared depending on mRNA of dexamethasone-treated fibroblasts by the PCR method including the rapid amplification of cDNA ends (RACE) protocol. The isolated cDNA had the same sequence as placental aromatase cDNA in the region encoded by exons 2-10. However, all 5'-fragments obtained from fibroblast aromatase cDNA contained a unique sequence in the region encoded by exon 1. A unique sequence was also deduced for the region between exons 1 and 2 of the placental aromatase gene from its cDNA, indicating that this region is used as an exon 1 by alternative splicing in skin fibroblasts. Tissue-specific use of multiple exons 1 in the splicing of aromatase transcripts was demonstrated by the mRNAs obtained from various tissues.

Adult↗
PubMed1992

Synergistic stimulation of nitric oxide hemoglobin production in rats by recombinant interleukin 1 and tumor necrosis factor.

Nitric oxide (NO) is formed from arginine in Escherichia coli lipopolysaccharide (LPS) treated rat; however, none of specific cytokine inducing NO generation is yet determined. We studied the effect of interleukin 1 (IL-1) and tumor necrosis factor (TNF) on NO production in rats by detecting NO-hemoglobin in their blood, using electron spin resonance. Either IL-1 or TNF alone stimulated NO-hemoglobin formation. Combined administration of IL-1 and TNF markedly enhanced NO-hemoglobin generation, demonstrating the synergistic character of both stimuli on NO production. Further, LPS and TNF in combination were more potent stimulator of NO-hemoglobin production in rats than each alone.

Animals↗
PubMed1992

Identification of an essential region for growth signal transduction in the cytoplasmic domain of the human interleukin-4 receptor.

Interleukin-4 (IL-4) is a pleiotropic lymphokine which plays an important role in the immune system by regulating proliferation and differentiation of a wide variety of lymphoid and myeloid cells. These biological effects are manifested via binding of IL-4 to specific membrane-associated high affinity receptors. While the IL-4 receptor (IL-4R) cDNA expresses high affinity binding sites when transfected in COS7 cells, its intracellular domain lacks consensus motifs for known signal transducing molecules such as a tyrosine kinase. In this study, we use a DNA deletion approach to explore the mechanism of signal transduction utilized by the human IL-4R cDNA expressed in a murine pro-B cell line, Ba/F3 cells. Using this system, we have identified the critical region of the cytoplasmic domain of human IL-4R for human IL-4-induced transduction of a growth signal in these cells. Our data indicate that the critical region for signal transduction is located between amino acid residues 433-473 numbering from the carboxyl terminus. This region is highly conserved between mouse and human IL-4R but lacks homology with other cytokine receptors. Our studies additionally demonstrate that the cytoplasmic domain is not essential for forming high affinity IL-4-binding sites nor for ligand internalization.

Amino Acid Sequence↗
PubMed1992

Granulocyte colony-stimulating factor receptors on human acute leukemia: biphenotypic leukemic cells possess granulocyte colony-stimulating factor receptors.

Granulocyte colony-stimulating factor (G-CSF) receptors on the gated leukemic blast cells from newly diagnosed patients with acute leukemia or crisis of chronic myelogenous leukemia were investigated using flow cytometric detection. Surface marker analysis and cytochemical studies were conducted simultaneously to characterize the blast cells. Among 24 leukemia cases examined, G-CSF receptor-positive blast cells were detected in all 11 cases of acute myeloblastic leukemia even though the percentage range of positive cells was widely variable. On the other hand, they were not detected on the blast cells from patients with peroxidase-negative acute lymphoblastic leukemia with no myeloid surface antigens. However, G-CSF receptors were demonstrated in significant amounts on blast cells from 5 of 8 cases of peroxidase-negative acute leukemia expressing both myeloid and lymphoid surface antigens (biphenotypic leukemia). The percentage of blast cells positive for G-CSF receptors was significantly smaller in biphenotypic cases [33 +/- 14% (SD)] than in acute myeloblastic leukemia cases [65 +/- 22%] (P less than 0.01). The percentage expression of CD13 antigen by blast cells was significantly related to their percentage positivity for G-CSF receptors (rs = 0.50, P less than 0.05). These findings indicate that the distribution of flow cytometrically detectable G-CSF receptors on leukemic cells possessing myeloid characteristics may be related to the maturation process.

Antigens, CD↗
PubMed1992

Detection of nitric oxide production in lipopolysaccharide-treated rats by ESR using carbon monoxide hemoglobin.

Release of nitric oxide (NO), from macrophages activated with E. coli lipopolysaccharide (LPS) and endothelial cells, has been proposed using chemiluminescence and spectrophotometry. However these methods can not distinguish NO from NO2-. The present study was aimed to prove in vivo production of NO, by ESR using CO-hemoglobin (HbCO) as a trapping agent of NO in the peritoneal cavity of rats treated with LPS. We detected a broad signal in the recovered HbCO solution. Inositol hexaphosphate induced a three-line hyperfine structure, characteristic of NO-hemoglobin (HbNO). In the arterial blood, ESR signal of HbNO with faint hyperfine structure was detected. NG-Monomethyl-L-arginine inhibited the formation of HbNO. HbNO was not detected in the peritoneal cavity of the LPS-untreated rat given i.p. both NO2- and HbCO. HbNO was, therefore, derived from NO, not from NO2-. These results show that free NO is produced in vivo by the stimulation of LPS.

Animals↗
PubMed1992

Expression and transport into mitochondria of bovine cytochrome P-450(SCC) in insect cells using the baculovirus expression system.

Bovine cytochrome P-450(SCC) introduced with the baculovirus host vector system was found to be expressed in Spodoptera frugiperda cells. Cell fractionation analysis indicated that the P-450(SCC) expressed as the precursor form was transported into mitochondria and converted to a mature form. However, this form did not exhibit definite activity for cholesterol side chain cleavage. These findings suggest that most of the P-450(SCC) expressed by this system is an inactive protein within mitochondria that is not folded to the conformation of the active enzyme and/or does not incorporate heme appropriately.

Animals↗
PubMed1992

Neuroanatomical specificity in the autoregulation of aromatase-immunoreactive neurons by androgens and estrogens: an immunocytochemical study.

Testosterone (T) increases brain aromatase activity (AA) in quail and other avian and mammalian species. It was shown both in quail and in rat that this enzymatic induction results from a synergistic action of androgens and estrogens. These studies provide little information on possible anatomical or cellular specificity of the effect. Using a polyclonal antiserum against human placental aromatase, we have previously identified aromatase-immunoreactive (ARO-ir) neurons in the quail brain and demonstrated that T increases the number of ARO-ir cells in the quail preoptic area (POA) supporting previous evidence that T increases AA in the brain. However, which T metabolites are involved, the actual mechanism of regulation and the possibility of anatomical specificity for these effects are not yet clear. In the present study, we disassociated the effects of androgens and estrogens in aromatase induction by comparing ARO-ir neurons of quail treated with T alone or T in the presence of a potent aromatase inhibitor (R76713), which has been shown to depress AA levels and to suppress T-activated copulatory behavior. T increased the number of ARO-ir cells in POA, bed nucleus striae terminalis (BNST) and tuberal hypothalamus (Tu). The T effect was inhibited by concurrent treatment with aromatase inhibitor in Tu, but not in POA and BNST. This differential effect of the aromatase inhibitor fits in very well with our previous studies of the co-localization of aromatase and estrogen receptors. The T effect was blocked by R76713 in areas where ARO-ir and estrogen receptor-ir are generally co-localized (Tu) and was not affected in areas with mainly ARO-ir positive, estrogen receptor-ir negative cells (POA, BNST). This suggests anatomical differences in the expression or clearance of aromatase which may be differentially sensitive to androgens and estrogens and dependent upon the presence of sex steroid receptors.

Animals↗
PubMed1992

Biochemical and molecular genetic analyses on placental aromatase (P-450AROM) deficiency.

Biochemical and molecular genetic studies were made on a case of placental aromatase (P-450AROM) deficiency. Of the enzymes participating in the electron transport system of placental microsomes, only aromatase activity was decreased specifically in the patient, being less than 0.3% of the normal activity. Northern and Western blotting analyses showed that the transcription of the aromatase gene and the translation of its mRNA proceeded normally in the placenta of this patient. However, aromatase cDNA isolated from a placental cDNA library of the patient was found to have an insert of 87 base pairs, encoding 29 amino acids in frame with no termination codon. The insert was located at the splicing point between exon 6 and intron 6 of the normal aromatase gene, and the extra DNA fragment was the first part of intron 6, except that its initial GT was altered to GC. These findings indicated that in this patient with aromatase deficiency, splicing between exon 6 and intron 6 did not occur at the normal position because of a point mutation in its consensus sequence and was forwarded to GT in the next cryptic consensus sequence 87 base pairs downstream according to the canonical GT/AG rule, resulting in translation of an abnormal protein molecule with 29 extra amino acids. During the transient expression in COS-7 cells, the aromatase cDNA of the patient was found to produce a protein with a trace of activity. This is the first report of a genetic defect for aromatase deficiency.

Amino Acid Sequence↗
PubMed1992

Chromosome-band-specific painting: chromosome in situ suppression hybridization using PCR products from a microdissected chromosome band as a probe pool.

We describe a chromosome-band-specific painting method that involves (1) microdissection of the chromosome, chromosomal region or band, (2) amplification of a variety of chromosome/region/band-specific DNA fragments with the polymerase chain reaction (PCR), and (3) chromosome in situ suppression hybridization (CISS) with the direct use of the PCR products as a probe pool. With this method, it was possible 1) to paint an entire X or Y chromosome, a distal one-fourth of 2q, and only a band at 8q24.1, 2) to identify the origin of a minute marker chromosome in a mentally retarded patient, 3) to detect an X;Y translocation in another patient, and 4) to identify one human chromosome 2 in a human-mouse hybrid cell line. This method allows us to identify not only structural chromosome abnormalities at the band level, but also the origin of cytogenetically unidentifiable marker chromosomes. It will also be useful in studies of evolutionary cytogenetics.

Base Sequence↗
PubMed1992

CD7-positive acute myeloid leukemia: further evidence of cellular immaturity.

Among 63 cases of acute myeloid leukemia (AML), 14 were found to express the CD7 antigen, a cell surface marker usually found at an early stage during T lineage differentiation. The CD7-positive AML cases consisted of 5 cases of M1, 3 cases of M2, 3 cases of M4, 1 case of M5, 1 case of M6 and 1 case of M7. Among these 63 cases, the proportion of blast cells expressing the CD34 antigen was examined. The proportion of CD34-stained cells among the CD7-positive AML cases, although varying, was significantly larger than that among the CD7-negative AML cases (P less than 0.05). As the CD34 antigen was expressed on hematopoietic progenitor cells and was considered to reflect an early hematopoietic stage, the high proportion of cells expressing CD34 among the CD7-positive AML cases may support the notion that CD7-positive AML cells are immature.

Adolescent↗