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Biomedical subjects

H Inoue

Publications and source records attributed to H Inoue.

At least 19 recordsLinked to original sources

Hepatocyte growth factor is linked by O-glycosylated oligosaccharide on the alpha chain.

The glycosylation site and the structure of O-glycosylated oligosaccharide of recombinant human HGF were investigated. N-acetylgalactosamine (GalNAc) in the alpha chain suggested the presence of O-glycosylated oligosaccharide. Sugar analysis and amino acid sequence analysis of peptide fragments produced by limited degradation revealed that O-glycosylated oligosaccharide linked to Thr445 of the alpha chain. The molecular weight of the oligosaccharide was determined with ion spray mass spectrometry. From these studies, the structure of the O-glycosylated oligosaccharide on the alpha chain of HGF was concluded as [formula: see text].

Amino Acid Sequence

Protection against bradykinin-induced bronchoconstriction in asthmatic patients by neurokinin receptor antagonist.

Axon reflex mechanisms may be involved in the pathogenesis of asthma, but there has been no direct evidence that endogenous tachykinins cause bronchoconstriction in asthmatic subjects. We have studied the effect of a tachykinin receptor antagonist (FK-224) on bronchoconstriction induced by inhalation of bradykinin in asthmatic patients. In a double-blind, placebo-controlled, crossover trial, ten subjects with stable asthma were given FK-224 (4 mg) or placebo by inhalation 20 min before challenge with bradykinin (0-1250 micrograms/ml, five breaths of each concentration) given with 5 min intervals. Bradykinin caused dose-dependent bronchoconstriction in all subjects. FK-224 significantly opposed the bronchoconstrictor effect; the geometric mean of the cumulative concentration required to elicit a 35% fall in specific airway conductance was 5.3 micrograms/ml after placebo and 40 micrograms/ml after FK-224 (p < 0.001). Inhalation of bradykinin caused coughing in three subjects, which was inhibited by FK-224 in all three. Antagonism of the tachykinin receptor by FK-224 greatly inhibited both bronchoconstriction and coughing induced by bradykinin in asthmatic patients, suggesting that tachykinin release from the airway sensory nerves is involved in responses to bradykinin. Tachykinin receptor antagonists may be useful in the treatment of asthma.

Administration, Inhalation

Putrescine-dependent invasive capacity of rat ascites hepatoma cells.

The effects of inhibitors of polyamine synthesis on the invasive capacity of rat ascites hepatoma (LC-AH) cells were examined by in vitro assay of penetration of the LC-AH cells through a monolayer of calf pulmonary arterial endothelial (CPAE) cells. Pretreatment of LC-AH cells with alpha-difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase, before seeding them onto a CPAE cell monolayer and culturing them for 24 h in the absence of DFMO decreased the number of penetrating tumor cells time and dose dependently (about 35% of the maximal inhibition) without affecting their viability or proliferative activity. DFMO treatment caused a marked decrease in the intracellular level of putrescine but not of spermidine or spermine. The DFMO-induced decreases in invasive capacity and putrescine level were almost completely reversed by the addition of putrescine to the medium during pretreatment with DFMO or invasion assay but were not affected by exogenous spermidine or spermine. No change in the invasive capacity was observed when the CPAE cells were treated with DFMO and the LC-AH cells with methylglyoxal-bis(guanylhydrazone), an inhibitor of S-adenosylmethionine decarboxylase, which depressed the spermidine and spermine levels but increased the putrescine level in the LC-AH cells. These results suggest that intracellular putrescine modulates the in vitro invasive capacity of LC-AH cells.

Animals

[MR imaging during arterio-portography (MR-AP) in the detection of hepatic cancer].

Magnetic resonance imaging during arterio-portography (MR-AP) was performed in 2 patients of hepatic cancer. Low dose of meglumine gadopentetate (4 ml of a 0.5 mmol/L solution) was injected into a superior mesenteric artery during acquisition of a Turbo-FLASH sequence. An increase in liver to lesion contrast was obtained with MR-AP and it is also useful in the late phase to distinguish a flow defect lesion due to portal obstruction from the tumor.

Gadolinium DTPA

Induction of uterine cervical neoplasias in mice by human papillomavirus type 16 E6/E7 genes.

We constructed a recombinant retrovirus containing the E6/E7 genes of human papillomavirus (HPV) 16 (ZE67) and examined the morphological changes in the cervicovaginal epithelium induced by inoculation of this virus into the vagina of mice. The ZNeo virus without HPV genes was used as a negative control. Moreover, cotreatment with phorbo-13-myristate-12-acetate or N-methyl-N'-nitro-N-nitrosoguanidine and these viruses was carried out. At the end of the observation period (9 months for CD-1 nu/nu and 15 months for C57BL/6J), of 31 CD-1 nude mice treated with ZE67, 7 and 19 had low-grade and high-grade dysplasia, respectively, while 5 of 22 mice treated with ZNeo had low-grade dysplasia (rank sum test, P less than 0.001). Similarly, 4 and 3 of 8 C57BL mice treated with ZE67 had low-grade and high-grade dysplasias, respectively, whereas 3 of the 8 control mice had low-grade dysplasias (P = 0.049). ZE67 plus phorbol-13-myristate-12-acetate and ZE67 plus N-methyl-N'-nitro-N-nitrosoguanidine cotreatments induced cervical cancers in 2 of 13 CD-1 nude mice and 6 of 15 C57BL mice, respectively. On the contrary, none of 6 CD-1 and 2 of 10 C57BL mice had cancer in the control groups (P = 0.0142 for phorbol-13-myristate-12-acetate treatment; P = 0.0173 for N-methyl-N'-nitro-N-nitrosoguanidine treatment). In addition, the existence and expression of HPV 16 E6/E7 genes were detected in the lesions induced by ZE67 but not in the lesions of the control mice by analysis by polymerase chain reaction and mRNA in situ hybridization. The present results suggest that HPV 16 E6/E7 genes induce dysplastic changes but require additional promoting or mutagenic stimulation for the development of cancer.

Animals

Photoaffinity labeling of T4 endonuclease V with a substrate containing a phenyldiazirine derivative.

T4 endonuclease V recognizes thymine photodimers in DNA duplexes and, in a two-step reaction, cleaves the glycosyl linkage of the 5'-side thymidine and the phosphodiester linkage. To determine the amino acid residues responsible for binding thymine photodimers, a photoaffinity reagent, 4-(1-azi-2,2,2-trifluoroethyl)-benzoate, was linked to the aminoalkylphosphonate of a thymine photodimer in a 14-mer duplex. The reactive substrate was treated with the enzyme under UV light (365 nm). The nascent enzyme and the modified enzyme were treated with lysyl endopeptidase, and the peptide maps were compared. Three peptides from the C terminus were found to interact with the reactive oligonucleotide to various extents. The three modified peptides were isolated and analyzed by Edman degradation. The amino acid residues Gly-133, Tyr-129, and Thr-89 were partially linked with the reactive substrate and may be involved in the binding of thymine photodimers.

Affinity Labels

Partial purification and characterization of membrane-associated diacylglycerol kinase of Drosophila heads.

A membrane-associated diacylglycerol kinase of Drosophila heads was purified to near homogeneity from the KCl extract of Drosophila heads. The purification procedure involved chromatography on Q-Sepharose, ammonium sulfate fractionation, Superose 12, hydroxyapatite and ATP-agarose. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of fractions after the ATP-agarose column chromatography showed that only a 115 kDa protein correlated well with the enzyme activity. The apparent Km values of partially purified DG kinase were 220 microM for ATP and 540 microM for diolein, respectively. The activity of the DG kinase was inhibited by deoxycholate and was not activated by Ca2+.

Animals

[Complications of arterial infusion of CDDP in the treatment of malignant neoplasms].

Arterial infusion of cis-diamminedichloroplatinum (CDDP) is an effective therapy for malignant neoplasms. Severe complications after this therapy in 298 patients with malignant tumors were reviewed in our institute from March 1982 to August 1989. Arteries infused with CDDP and the number of infusions were as follows: bronchial artery (a.) 277, hepatic a. 153, internal iliac a. 51, femoral or popliteal a. 15, lumbar a. 6, pulmonary a. 5, esophageal a. 3 and intercostal a. 3. Eight cases of severe complications were encountered: 3 of esophageal ulcer, 3 of spinal paralysis, and one each of mediastinitis and toe necrosis. The arteries responsible for complications were the bronchial a. in 3 cases of esophageal ulcer and 2 of spinal paralysis, intercostal a. in one of spinal paralysis, esophageal a. in one of mediastinitis and popliteal a. in toe necrosis. Complication rates were 2.7% (8/298 cases) and 1.5% (8/518 infusions). Angiotensin II was infused in 6 of 8 of the cases with complications. The complication rate was 2.9% (6/209 infusions) in the group with CDDP and angiotensin II and 0.6% (2/309 infusions) in the group with CDDP only. Arterial infusion of CDDP, especially combined with angiotensin II, should be done in consideration of the arteries responsible for such complications.

Adenocarcinoma

An immunomodulatory protein, Ling Zhi-8, facilitates cellular interaction through modulation of adhesion molecules.

Ling Zhi-8 (LZ-8), a novel immunomodulatory protein, markedly enhanced the expression of CD11b, but not CD11a, CD13, CD14, CD18, CD33 or HLA-DR, on the U937 cell line in a dose-dependent fashion. It also induced ICAM-1 expression on vascular endothelial cells and significantly augmented gamma - interferon-induced cellular binding between vascular endothelial cells and U937. Furthermore, LZ-8 increased the expression of CD2, but not VLA4, VLA5 or LFA3, on MOLT4 and enhanced rosette formation between human T cells and sheep red blood cells. These data suggest that LZ-8 exerts its pharmacological effect by modulating adhesion molecules on immunocompetent cells.

Adjuvants, Immunologic

The human gene for renin-binding protein.

The human renin-binding protein (RnBP) gene was isolated from a human placental genomic library and characterized. The gene spans about 10 kilobases and consists of 11 exons separated by 10 introns. The 5'-flanking region and the exon-intron boundaries were sequenced. Residue G* in 5'-CGAG*TGG-3' was identified as the major transcription initiation site, and "GC" boxes were found in the vicinity of the cap site. No typical "TATA" or "CCAAT" box exists in the 5'-flanking region. The hydrophobic domain followed by a leucine-zipper motif in RnBP is encoded by the sixth exon. A fragment of the human RnBP gene (nucleotides -739 to +244) linked to the chloramphenicol acetyltransferase gene was transfected into human Wilms' tumor G401 and mouse L929 cells. The expression of this chimeric gene in G401 cells was 4-fold higher than that in L929 cells, the tissue-specific regulation of RnBP gene expression thus being suggested. The promoter for the RnBP gene was shown to be localized in nucleotides -35 to +244 on assaying of the promoter activity using deletion mutants of the chimeric constructs. The RnBP gene was found to be located in human chromosome X by means of polymerase chain reaction of hybrid DNAs from human and hamster somatic cells.

Animals

c-Ha-ras containing 8-hydroxyguanine at codon 12 induces point mutations at the modified and adjacent positions.

To determine the type of mutation induced by 8-hydroxyguanine in a mammalian system, we examined the mutations induced by a synthetic c-Ha-ras protooncogene containing 8-hydroxyguanine in the second position of codon 12 (GGC) in NIH3T3 cells. Transfection of this gene significantly increased the number of transformed foci. The c-Ha-ras gene present in these foci was analyzed by the polymerase chain reaction-restriction enzyme method. Interestingly, sequence analysis revealed random mutations at the modified site (G----T, G----A, and G----C) as well as mutations of the adjacent G on the 5'-side of 8-hydroxyguanine (G----A and G----T).

3T3 Cells

[Angiographic features of alveolar soft-part sarcoma].

The angiographic findings were analyzed in five patients with alveolar soft-part sarcoma. The angiographic appearance of the tumors was the same in all five cases: hypervascularity of the tumor including encasement, dilatation, tortuosity and displacement of feeding arteries, remarkable tumor stain and early venous filling. These angiographic findings are considered to be characteristic of alveolar soft-part sarcoma in the differential diagnosis of hypervascular soft tissue mass.

Adult

Oligo(2'-O-methyl)ribonucleotides. Effective probes for duplex DNA.

To find novel probes for duplex DNA, we prepared four types of triplexes containing a homopurine-homopyrimidine 15-mer duplex DNA, and examined their thermal stabilities (Tm values). The single strand used for triplex formation were a DNA 15-mer having a defined C-T mixed sequence, and its sugar-modified analogs, namely 2'-fluoro DNA, RNA, and 2'-O-methyl RNA. The 2'-O-methyl RNA and the RNA-containing triplexes were similar in their enhanced stabilities at pH 6.1 and, amongst the four triplexes, the 2'-O-methyl was the most stable at pH 5.0. Furthermore, an experiment using a 34-mer duplex DNA suggested that the 2'-O-methyl RNA-triplex was destabilized, mostly as a result of the incorporation of a mismatched triplet, as compared to the DNA triplex counterpart. Thus, 2'-O-methyl RNA can serve as an effective probe for duplex DNA.

Base Sequence

A hybrid ribonuclease H. A novel RNA cleaving enzyme with sequence-specific recognition.

A hybrid enzyme which site-specifically hydrolyzes RNA was created by covalently linking an oligodeoxyribonucleotide to Escherichia coli ribonuclease HI, an enzyme which specifically cleaves RNA moiety of DNA/RNA hybrids. A cysteine residue was substituted for Glu135 by site-directed mutagenesis in the mutant enzyme, in which all 3 free cysteine residues were replaced by alanine (Kanaya, S., Kimura, S., Katsuda, C., and Ikehara, M. (1990) Biochem. J. 271, 59-66), and coupled with a maleimide group, which is attached to the 5' terminus of the nonadeoxyribonucleotide (5'-GTCATCTCC-3') with a flexible tether. The resulting hybrid enzyme, d9-C135/RNase H, cleaved the phosphodiester bond between the fifth and sixth residues of the complementary nonaribonucleotide, without addition of the oligodeoxyribonucleotide. The nonaribonucleotide is cleaved by the wild-type or unmodified mutant enzyme only when the complementary oligodeoxyribonucleotide is present. When the kinetic parameters of the hybrid enzyme for the hydrolysis of the nonaribonucleotide were compared with those of the unmodified mutant enzyme for the hydrolysis of the nonanucleotide duplex, the hybrid enzyme exhibited a 7- and 4-fold decreases in the Km and kcat values, respectively, indicating that it performs multiple turnovers and has a sufficiently high hydrolytic activity. Hybrid ribonucleases H with various oligodeoxyribonucleotides in size and sequence, therefore, might be used as excellent tools for structural and functional studies of RNA.

Autoradiography

Tyrosine-7 in human class Pi glutathione S-transferase is important for lowering the pKa of the thiol group of glutathione in the enzyme-glutathione complex.

Previously, we reported the importance of Tyr7 for the catalytic activity of human class Pi glutathione S-transferase [Kong et al. (1992) Biochem. Biophys. Res. Comm., 182, 1122]. As an extension of this study, we investigated the pH dependence of kinetic parameters of the wild-type enzyme and the Y7F mutant. The replacement of Tyr7 with phenylalanine was found to alter the pH dependence of Vmax and Vmax/KmCDNB of the enzyme for conjugation of GSH with 1-chloro-2,4-dinitrobenzene (CDNB). The pKa of the thiol of GSH in the wild-type enzyme-GSH complex was estimated to be about 2.4 pK units lower than that in the Y7F-GSH complex. Tyr7 is thus considered to be important for catalytic activity in lowering the pKa of the thiol of GSH in the enzyme-GSH complex.

Amino Acid Sequence

Relationship between tumor DNA ploidy and regional lymph node changes in lung cancer.

Seventy-four patients with lung cancer, resected consecutively from April 1989 to August 1990, were divided into (1) 21 with diploid tumors having a single G0/G1 peak and a coefficient of variation (CV) of 4.9 or less, (2) 18 with peridiploid tumors having a single G0/G1 peak and a CV at 5.0 or more, and (3) 35 with aneuploid tumors having multiple G0/G1 peaks. Aneuploid tumors had higher frequencies of lymphatic invasion and metastasis to the mediastinal lymph nodes. To evaluate the relationship between ploidy tumor status and immunologic competence of the regional lymph nodes, histologic findings and the proportion of killer T-lymphocytes were examined in the dissected lymph nodes. Aneuploid tumors had significantly lower proportions of paracortical hyperplasia and killer T-lymphocytes than did diploid and peridiploid ones in the nonmetastatic lymph nodes of N0 and N1 disease. These findings suggest the possibility that a decline in the antitumor competence of these lymph nodes could cause metastasis to the nodes. The recurrence rates were 19% in diploid, 33% in peridiploid, and 54% in aneuploid tumors, and the 2-year survival rates were 87%, 78%, and 44%, respectively. Peridiploid tumors showed intermediate values between diploid and aneuploid in terms of immunologic competence, recurrence rate, and survival. They were assumed to have a different proportion of aneuploid cells than the other two.

Aged

Sequence-dependent cleavage of DNA by alkylation with antisense oligodeoxyribonucleotides containing a 2-(N-iodoacetylaminoethyl)thio-adenine.

Antisense oligodeoxyribonucleotides (15mers), containing a 2-(N-iodoacetylaminoethyl)thio-adenine, were synthesized and tested for their ability to cleave complementary DNAs (21mers). Cleavage of the target DNAs was done by alkylation followed by treatment with piperidine, and the positions of the alkylated sites were estimated by identification of the cleaved products. By using several combinations of the modified strands and their target DNAs, it was determined that alkylation occurred at adenine or guanine, depending on the torsion angle of the modified nucleoside.

Adenine