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H Nishimura

Publications and source records attributed to H Nishimura.

At least 361 records · Page 20Linked to original sources
PubMed1994

Identification of regions of bovine factor VII essential for binding to tissue factor.

Initiation of the extrinsic blood coagulation pathway is mediated by a complex formed between plasma-derived factor VII/VIIa and cell-derived tissue factor (TF). To identify the site(s) of interaction, zymogen VII and VIIa were enzymatically and chemically modified, and their affinities for TF were estimated by measuring their inhibitory effects on the amidolytic activity enhanced after formation of the VIIa-TF complex. We found that the VIIa-light chain (Ki = 3.5 x 10(-7) M) and its fragment consisting of the gamma-carboxyglutamic acid (Gla)-domain and the first epidermal growth factor (EGF)-like domain (Gla-EGF1 peptide; Ki = 1.0 x 10(-6) M) have an affinity for TF. Therefore, one of the binding sites of VII with TF is probably located in the Gla-EGF1 region. On the other hand, a dansyl-Glu-Gly-Arg chloromethyl ketone-treated Gla-domainless VIIa (Ki = 0.7 x 10(-7) M) showed a high affinity for TF, whereas the corresponding Gla-domainless VII similarly treated showed no binding potential, thereby indicating that binding site(s) other than in the Gla-EGF1 region are present in VIIa but not in VII. Acetylation or carbamylation of the alpha-amino group of the NH2-terminal Ile-153 of VIIa resulted in the loss of binding affinity for TF; such modifications convert VIIa into a zymogen-like inactive form by destroying the salt bridge between Ile-153 and Asp-343 in VIIa. The rate of carbamylation of VIIa was reduced in the presence of TF. Protection of the alpha-amino group of Ile-153 from carbamylation after complex formation was consistent with salt bridge formation between Ile-153 and Asp-343 in the VIIa-TF complex. Therefore, binding of TF with the heavy chain of VIIa may induce a conformational change that brings the alpha-amino group of Ile-153 close to the beta-carboxyl group of Asp-343 to make a stable salt bridge.

1-Carboxyglutamic Acid↗
PubMed1994

Activation peptide of human factor IX has oligosaccharides O-glycosidically linked to threonine residues at 159 and 169.

O-Linked oligosaccharide chains were identified in the activation peptide (AP) of human blood coagulation factor IX. The peptide obtained from human factor IX was separated into three molecular species (AP alpha, AP beta, and AP gamma) by reversed-phase high-performance liquid chromatography. Amino acid analysis showed that AP alpha, but not AP beta and AP gamma, contained galactosamine in addition to glucosamine, thereby suggesting the presence of an O-linked sugar chain(s) in the molecule of AP alpha. A nonapeptide (AP alpha-D4, residues 157-165) and an undecapeptide (AP alpha-D5, 166-176) derived from AP alpha contained Thr-159 and Thr-169, neither of which could be identified using a gas-phase protein sequencer. All other serine and threonine residues present in AP alpha were identified by peptide sequencing. Component sugar and sialic acid analyses of AP alpha-D4 and AP alpha-D5 revealed that they contained 1 mol each of N-acetyl-D-galactosamine (GalNAc), D-galactose (Gal), and sialic acid. Fast atom bombardment tandem mass spectrometric analysis of AP alpha-D4 suggested the existence of Gal-GalNAc-Thr, NeuNAc-(Gal-)GalNAc-Thr, and NeuNAc-Gal-GalNAc-Thr structures. On the basis of amino acid analysis after the isolation of AP alpha, it accounted for approximately 35% of the total activation peptide obtained. From these results, it was concluded that a part of the activation peptide of human factor IX in circulating blood has tri- and tetrasaccharides O-glycosidically linked to the threonine residues at 159 and 169.

Amino Acid Sequence↗
PubMed1994

A unique murine CD43 epitope Lp-3: distinct distribution from another CD43 epitope S7.

In foregoing studies, we found a unique B cell differentiation antigen Lp-3 which is expressed on pre-B and premature B cells in the bone marrow, but is negative on bone marrow mature B cells and peripheral resting B cells. Nonetheless, Lp-3 was clearly positive on the majority of CD5 B(B1) cells. When we examined the biochemical nature and partial amino acid sequences of purified 132-kDa Lp-3 molecules and the nucleotide sequence of the cDNA clones, we found that Lp-3 is an epitope of CD43. Thus, the monoclonal antibody (mAb) Lp-3 may be the first mAb to murine CD43 defined by primary target structure analysis. Comparison of tissue distribution of Lp-3 and S7, an epitope previously suggested to associate with murine CD43, showed that they were similarly distributed on thymocytes, peripheral B and T cells, granulocytes, and platelets. In the bone marrow, while both Lp-3 and S7 were negative on mature B cells, the former was positive on all B lineage cells at an early ontogeny and the latter was positive only on the minor population of pre-B cells and pro-B cells. Lp-3 and S7 epitopes also showed different distributions on basement membranes of renal glomerulus, bronchus, and endometrium, lining cells of choroid plexus and muscular cells of arterioles in a variety of tissues. As CD43 has various isoforms generated by different degrees of glycosylation of the common core peptide, it is likely that Lp-3 and S7 are associated with different CD43 isoforms.

Amino Acid Sequence↗
PubMed1994

The ability of influenza C virus to generate cord-like structures is influenced by the gene coding for M protein.

We observed previously that cord-like structures which had lengths up to 500 microns or greater were protruding from the surface of HMV-II cells infected with influenza C/Yamagata/1/88 virus (Nishimura et al., 1990, Virology 179, 179-188). Comparison of the cord-forming ability among a number of influenza C isolates revealed that the C/Taylor/1233/47 strain was unique in lacking the ability. It was also found that the major structural proteins, hemagglutinin-esterase (HE), nucleoprotein (NP), and matrix (M), could each be distinguished between C/Yamagata/1/88 and C/Taylor/1233/47 viruses by SDS-polyacrylamide gel electrophoresis. To determine the genes involved in the cord formation, a series of reassortant viruses were prepared between C/Yamagata/1/88 and C/Taylor/1233/47, and parental derivation of genes coding for HE, NP, and M was determined by gel electrophoresis. All reassortants which derived M gene from C/Yamagata/1/88, irrespective of derivation of genes coding for HE and NP, had the ability to generate cords, whereas none of reassortants which derived M gene from C/Taylor/1233/47 were capable of producing cords. With respect to several representative reassortants, the origins of genes encoding the polymerase proteins (PB2, PB1, P3) and the nonstructural proteins (NS1, NS2) were determined by T1-oligonucleotide fingerprinting of the isolated RNA segments. The results suggested that none of genes coding for these proteins are exclusively associated with the cord formation. Thus, it is likely that the M gene is the key determinant of the cord-forming ability of influenza C viruses. Nucleotide sequence analysis of the M genes revealed that compared to C/Yamagata/1/88, C/Taylor/1233/47 had two amino acid substitutions in the M molecule at positions 24 (Ala-->Thr) and 133 (Asp-->Asn).

Base Sequence↗
PubMed1994

Metallothionein mRNA in the testis and prostate of the rat detected by digoxigenin-labeled riboprobe.

Metallothionein (MT), a cysteine-rich heavy metal-binding protein, has been considered to play a role in the homeostatic control and detoxification of heavy metals, such as zinc, copper, and cadmium. In the present study, we have utilized a digoxigenin-labeled riboprobe to localize MT mRNA only by bright-field optics in the testis and prostate of the rat. In the rat testis, MT mRNA was found predominantly in primary spermatocytes and also in secondary spermatocytes and spermatids, but not in the spermatogonia, Sertoli cells, and Leydig cells. On the other hand, MT protein was present in these spermatogenic cells as well as in spermatozoa and Sertoli cells. In the prostate, MT mRNA was found predominantly in the epithelium of the dorsolateral lobes, but not in the ventral lobe, which is in agreement with the observed localization of MT protein. The utilization of both in situ hybridization and immunohistochemical staining on the same tissue specimens show MT gene expression in specific cell types in the male genital organs.

Animals↗
PubMed1994

Corticosteroid-responsive parkinsonism associated with primary Sjögren's syndrome.

A 74-year-old woman with primary Sjögren's syndrome confirmed by salivary gland biopsy presented with parkinsonism. Magnetic resonance imaging (MRI) of the brain revealed multiple small high intensity lesions in the deep white matter, basal ganglia and pons on T2-weighted images. Treatment with L-dopa failed to improve the parkinsonian features. After the initiation of prednisolone 30 mg/day, the parkinsonian signs and symptoms significantly improved. Some lesions on MRI were decreased in size after corticosteroid therapy. These findings suggest that parkinsonism associated with primary Sjögren's syndrome is at least in part attributable to small vessel vasculopathy such as focal inflammation or edema.

Aged↗
PubMed1994

Amoxicillin concentration in pus from abscess caused by odontogenic infection.

1. Amoxicillin concentration in pus from odontogenic infection was assayed and the concentrations were compared with MIC (minimum inhibitory concentration) of alpha-hemolytic streptococci isolated from odontogenic infection. 2. Measurable amoxicillin concentrations in serum and pus were found in all instances (n = 16). 3. The mean peak concentrations in serum and pus were found at identical times, 1.5 hr after administration, which were 5.92 and 0.90 micrograms/ml, respectively. 4. The mean concentration ratio of pus/serum at the peak time was 0.15. 5. All amoxicillin concentrations in pus at the peak time exceeded the MIC for 90% of alpha-hemolytic streptococci (0.25 micrograms/ml).

Administration, Oral↗
PubMed1994

Cephalexin concentrations in radicular granuloma following a single oral administration of 250- or 500-mg cephalexin.

1. Cephalexin concentrations in radicular granuloma and serum following a single oral administration of 250- or 500-mg cephalexin were measured by a paper disk method. 2. The highest concentration of cephalexin in radicular granuloma following administration of 250-mg cephalexin to nonfasting patients was observed at 2 hr, and was 1.62 micrograms/g. The mean cephalexin concentration ratio of radicular granuloma/serum at 2 hr was 0.35. 3. The highest concentrations of cephalexin in radicular granuloma following administration of 500-mg cephalexin to nonfasting and fasting patients occurred at 2 and 1.5 hr, and was 3.35 and 3.42 micrograms/g, respectively. Mean cephalexin concentration ratios of radicular granuloma/serum at 2 and 1.5 hr were 0.32 and 0.30, respectively. 4. All mean cephalexin concentrations in radicular granuloma following administration of 500-mg cephalexin to both fasting and nonfasting patients exceeded MIC for 90% (2 micrograms/ml) of clinically isolated strains of alpha-hemolytic streptococci. However, those concentrations obtained by 250-mg cephalexin did not exceed it.

Adult↗
PubMed1994

Mapping of a gene for hypergammaglobulinemia to the distal region on chromosome 4 in NZB mice and its contribution to systemic lupus erythematosus in (NZB x NZW)F1 mice.

IgM class hypergammaglobulinemia develops spontaneously in the early life of NZB mice. To determine the chromosomal location of the NZB gene(s) linked to this hypergammaglobulinemia and possible contribution to systemic lupus erythematosus (SLE)-like autoimmune disease observed in (NZB x NZW)F1 hybrid mice, we examined (NZB x NZW)F1 x NZW backcross mice, using a mapping technique based on polymorphism in simple nucleotide sequence repeats. In light of our previous data, we directed attention to chromosome 4. A single NZB locus or tightly linked group of loci on the distal region (70-90 cM distal from the centromere), theoretically mapped to 14.3 cM distal from marker locus D4Mit48, had the strongest association with IgM hypergammaglobulinemia. The backcross progeny heterozygous for this locus on chromosome 4, in association with heterozygosity of the MHC haplotype (H-2d from NZB/H-2z from NZW) on chromosome 17, showed significantly higher serum levels of IgG anti-DNA antibodies and more severe lupus nephritis than did the progeny heterozygous for either one of the two loci or homozygous for both loci on chromosomes 4 and 17. The NZB gene in the distal region of chromosome 4 is likely to be responsible for terminal maturation of B cells and, in concert with the effect of H-2 heterozygosity, may predispose to the full expression of SLE in (NZB x NZW)F1 mice.

Animals↗
PubMed1994

Converting enzyme inhibition improves congestion and survival in hypertensive rats with high-output heart failure.

The effects of angiotensin-converting enzyme (ACE) inhibitors in high-output heart failure have not yet been well established. We evaluated the effects of lisinopril (3 mg/kg/day) on hemodynamics, neurohormones, and survival in 10-week-old spontaneously hypertensive rats (SHR) with aortocaval fistula. Sham-operated treated and untreated SHR served as controls. Cardiac output (CO) was determined by thermodilution method, and renal blood flow (RBF) was assessed by laser-Doppler flowmetry. In sham-operated SHR, 2-week treatment with lisinopril decreased blood pressure (BP), left ventricular (LV) weight, and total peripheral resistance (TPR) (p < 0.01 each) and increased RBF and plasma renin activity (PRA) (both p < 0.05); CO and LV end-diastolic pressure (LVEDP) were unchanged. Fistula creation induced biventricular hypertrophy and high-output heart failure [increased LVEDP, CO, pulse pressure, and plasma norepinephrine (NE) and decreased RBF] with congestive signs (ascites, tachypnea). Lisinopril decreased LVEDP (p < 0.01), increased RBF, prolonged survival (both p < 0.05), and prevented ascites (0 vs. 46%) and increased PRA (p < 0.05) and attenuated the increase in plasma NE. Heart weight, BP, and CO were not affected by lisinopril. Thus, lisinopril ameliorated congestion and improved survival in SHR with fistula without compromising cardiorenal hemodynamics. Venous and renal dilatation and attenuation of vasoconstrictive systems may have contributed to the beneficial effects.

Animals↗
PubMed1994

Identification of a second protein encoded by influenza C virus RNA segment 6.

Influenza C virus matrix protein (M1) is encoded by a spliced mRNA derived from RNA segment 6. Unspliced mRNA from this RNA segment, which has not been previously identified, can potentially encode a polypeptide that contains an additional 132 amino acids on the carboxy terminus of the M1 protein. Here the nucleotide sequences of RNA segment 6 of four influenza C strains, isolated in Japan between 1964 and 1988, were compared with the previously determined sequence of C/Ann Arbor/1/50. The results indicated that the deduced amino acid sequence of the carboxy-terminal 132 amino acid domain is conserved fairly well although it is more divergent than the M1 protein sequence. Examination of RNA segment 6-specific mRNAs also showed that unspliced mRNA is present, although in small quantities (approximately 13% of spliced mRNA), in influenza C virus-infected cells. To search for a polypeptide encoded by the unspliced mRNA, the extra carboxy-terminal domain was expressed in Escherichia coli as the glutathione S-transferase fusion protein, and rabbit immune serum was raised against the purified fusion protein. Immunoprecipitation experiments with this antiserum revealed that a previously unrecognized protein of apparent M(r) approximately 18,000, designated CM2, is synthesized in influenza C virus-infected cells.

Amino Acid Sequence↗
PubMed1994

Genetic reassortment of influenza C viruses in man.

We reported previously that the antigenicity of the haemagglutinin-esterase (HE) glycoprotein of the human influenza C virus strain C/Nara/1/85 was indistinguishable from that of strain C/Nara/82. However, the ribonuclease T1-oligonucleotide map of total virion RNA of C/Nara/1/85 differed remarkably from the map of C/Nara/82, resembling instead the map of C/Nara/2/85, which has an HE antigenicity dissimilar to C/Nara/82 and C/Nara/1/85. This observation raised the possibility that C/Nara/1/85 might have arisen by reassortment from two viruses closely related to C/Nara/82 and C/Nara/2/85, respectively. Here, we compared the total nucleotide sequence of the HE gene and partial sequences of the other genes of C/Nara/1/85 with those of C/Nara/82 and C/Nara/2/85. The results suggest that C/Nara/1/85 has inherited HE and NP genes from a C/Nara/82-related virus and the PB2, PB1, PA, M and NS genes from a C/Nara/2/85-related virus.

Base Sequence↗