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Biomedical subjects

S Inoue

Publications and source records attributed to S Inoue.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Detection of cortical infarcts in brain MR imaging: feasibility of short-TR-T2-weighted imaging using a fast spin echo sequence].

MRI of the brain using a fast SE sequence is often performed with a TR above 5000 msec, so there is a tendency for the signal of CSF to become too high. However, when cerebral atrophy is marked, small lesions of the brain parenchyma can be hard to detect. Therefore, we examined short-TR-T2-weighted images using a fast spin echo sequence. The 58 subjects included 33 men and 25 women, and cortical infarction was detected in five of them. On the short-TR-T2WI sequences, the infarct lesions were imaged as areas of higher signal intensity than cerebrospinal fluid, the signal of which was reduced. In cortical infarction cases, fluid-attenuated inversion recovery (FLAIR) images can detect the lesion more easily, but FLAIR sequences cannot be obtained with all MR equipment. Short-TR-T2WI, which readily yields images comparable to those of FLAIR, is an useful method.

Cerebral Cortex↗
PubMed1995

[Postoperative analgesia service by continuous epidural infusion with buprenorphine].

We examined the analgesic efficacy and side effects of continuous epidural infusion with buprenorphine in 340 surgical patients. The patients received epidural injection of 0.1 mg of buprenorphine in 8 ml of 0.25% bupivacaine immediately after surgery. The patients who underwent thoracotomy or intraabdominal surgery were subsequently infused with buprenorphine 15 micrograms in 1 ml of 0.25% buprenorphine at a rate of 1 ml.h-1 for 48 h. In the other kinds of surgery, patients were infused with buprenorphine 8 micrograms in 1 ml of 0.25% buprenorphine at a rate of 1 ml.h-1 for 48 h. The patients who did not need additional narcotics were 68% and 83% on the postoperative day 1 and 2, respectively. Visual analogue scale (VAS) was 22 +/- 2 mm at rest and 43 +/- 2 mm at movement on the postoperative day 1. Corresponding values on the postoperative day 2 were 16 +/- 2 mm and 37 +/- 2 mm, respectively. Nausea and vomiting were found in 12.4% of the patients.

Adolescent↗
PubMed1995

[Identification of viable myocardium using 99mTc-tetrofosmin scintigraphy--comparison with 201Tl redistribution-reinjection images].

The purpose of this study was to clarify the diagnostic value of identifying viable myocardium using 99mTc-Tetrofosmin scintigraphy. Twenty-one patients with chronic coronary artery disease were studied using 201Tl exercise myocardial scintigraphy with reinjection and 99mTc-Tetrofosmin exercise myocardial scintigraphy. All patients had a history of old myocardial infarction. For 99mTc-Tetrofosmin scintigraphy, 222 MBq of 99mTc-Tetrofosmin was injected during exercise, and exercise images were obtained 20 min thereafter. There hours later, 666 MBq of 99mTc-Tetrofosmin was injected at rest, and images were obtained 40 min and 220 min later. Myocardial viability in the 99mTc-Tetrofosmin scintigraphy was estimated as fill-in findings (FF) or over 50% of %RI uptake (%TF) in the rest image. Myocardial viability in the 201Tl scintigraphy was estimated as redistribution (RD), fill-in findings in the reinjection image (FR) or over 50% of %RI uptake in the reinjection image (% TL). Sixteen of the 21 patients (76%) who underwent 201Tl scintigraphy (RD 10, FR 3, %TL 3 cases) and 15 of the 21 patients (71%) who underwent 99mTc-Tetrofosmin scintigraphy (FF 11, %TF 4 cases) had viable myocardium in the infarcted area. A comparison between the 99mTc-Tetrofosmin rest images obtained 40 min after the injection and that of 220 min revealed no redistribution findings. The %RI uptake of the infarcted area in the resting 99mTc-Tetrofosmin image (47 +/- 16%) was slightly lower than that in the 201Tl reinjection image (52 +/- 16%). In conclusion, viable myocardium was as clearly identified by 99mTc-Tetrofosmin, as by 201Tl scintigraphy.

Aged↗
PubMed1995

[Simultaneous evaluation of myocardial perfusion and fatty acid metabolism using dynamic SPECT with single injection of 123I-15-(p-iodophenyl)-3-methyl pentadecanoic acid (BMIPP)].

The purpose of this study is to clarify whether dynamic SPECT (DECT) immediately after the injection of 123I-15-(p-iodophenyl)-3-methyl pentadecanoic acid (BMIPP) may represent myocardial perfusion imaging. Ten patients with unstable angina pectoris (UAP), 11 patients with acute myocardial infarction (AMI) and 6 patients with non-ischemic heart disease (NIHD) were studied using BMIPP myocardial scintigraphy with DECT. DECT acquisition was started 2 minutes after the injection of BMIPP, and DECT images were obtained every three minute for 15 minutes with 3-headed gamma camera SPECT system. Additionally, static SPECT images were acquired 30 minutes after the injection of BMIPP. These SPECT images of BMIPP were compared with thallium-201 myocardial perfusion images at rest. In UAP group, early DECT images showed almost the same findings as thallium-201 images in 8 of 10 patients, and SPECT images at 30 minutes after the injection showed reduced accumulation of BMIPP compared with thallium-201 images in all patients. In AMI group, early DECT images showed the same findings as thallium-201 perfusion images in 9 of 11 patients, and SPECT images at 30 minutes after the injection showed reduced accumulation of BMIPP compared with thallium-201 images in 5 of 11 patients. These results indicate that myocardial perfusion can be evaluated in the early image using DECT, in addition to myocardial fatty acid metabolism in the delayed image.

Adult↗
PubMed1994

Demonstration of activin-A in arteriosclerotic lesions.

We previously reported that follistatin, an activin-binding protein, is produced in arteriosclerotic lesions. Here, the expression of activin-A which promotes the growth of vascular smooth muscle cells was examined in arteriosclerotic lesions of WHHL (Watanabe heritable hyperlipidemic) rabbits. Activin-A mRNA was detected in normal aorta by reverse transcriptase-polymerase chain reaction using specific primers for activin-A cDNA and was increased remarkably in arteriosclerotic lesions. In addition, using the cloned rabbit activin-A cDNA, RNA probe was prepared and in situ hybridization histochemistry was performed. Activin-A transcripts were detected abundantly in neointima of the diseased artery. Furthermore, immunohistochemistry also detected activin-A at the protein level. These observations suggest that activin-A is a cytokine expressed in arteriosclerotic lesions and might be involved in the pathogenesis of atherosclerosis.

Activins↗
PubMed1994

Differential reactivity of two types of N-glycolyneuraminic acid dimers toward enzymatic and nonenzymatic hydrolysis of their interketosidic linkages.

The kinetics of acid- and sialidase-catalyzed hydrolysis of the interketosidic linkages of two different disialic acids, Neu5Gc alpha 2-->5-OglycolylNeu5Gc and Neu5Gc alpha 2-->8Neu5Gc, were studied. The former sequence was recently identified in the polysialic acid chains of a sialic acid-rich glycoprotein isolated from the egg jelly coat of two different species of sea urchins, and the latter was previously found in the cortical alveolar-derived polysialoglycoprotein from rainbow trout eggs. At pH values < 3.8, the rate of hydrolysis of Neu5Gc alpha 2-->5-OglycolylNeu5Gc was greater than that of Neu5Gc alpha 2-->8Neu5Gc. Paradoxically, however, Neu5Gc alpha 2-->5-OglycolylNeu5Gc was more stable than Neu5Gc alpha 2-->8Neu5Gc at pH values > 3.8. These findings indicate a greater contribution of intramolecular general acid catalysis to the lability of the alpha 2-->5-ketosidic linkage. Neu5Gc alpha 2-->5-OglycolylNeu5Gc was a poor substrate for Arthrobacter ureafaciens, Clostridium perfringens, and Vibrio cholerae sialidases, in contrast to Neu5Gc alpha 2-->8Neu5Gc. Neu5Gc alpha 2-->5-OglycolylNeu5Gc was essentially resistant to hydrolysis by A. ureafaciens sialidase.

Carbohydrate Sequence↗
PubMed1994

Molecular cloning of human cytosolic purine 5'-nucleotidase.

The cDNA of human cytosolic purine 5'-nucleotidase (EC 3.1.3.5), which is the supposed regulatory allosteric enzyme of purine nucleotide degradation, has been cloned from a human placenta cDNA library. The predicted open reading fram encodes a protein of 561 amino acids with a molecular mass of 64,966 Da. The deduced amino acid sequence exhibits 95% identity with the sequence of the B type subunit of chicken cytosolic purine 5'-nucleotidase. Northern blot analysis of human placenta poly(A) +RNA revealed a single band of 3.6 kilobases using the cloned cDNA.

Amino Acid Sequence↗
PubMed1994

The two subunits of a phospholipase A2 inhibitor from the plasma of Thailand cobra having structural similarity to urokinase-type plasminogen activator receptor and LY-6 related proteins.

Amino acid sequences of the two subunits (31-kDa and 25-kDa subunits) of a phospholipase A2 (PLA2) inhibitory protein, purified from the blood plasma of Thailand cobra Naja naja kaouthia, were determined by alignment of peptides obtained by lysyl endopeptidase, staphylococcal V8 protease and endoproteinase Asp-N digestions. The respective subunits were composed of 188 and 185 amino acid residues, and the former contained one asparagine-linked sugar chain at the position 157. There was 29% identity between 31-kDa and 25-kDa subunits. The analysis of internal homology in each sequence of the two subunits revealed the existence of two repeats of approximately 90 amino acid residues. These sequence units were found to be significantly homologous to those of urokinase-type plasminogen activator receptor and of Ly-6 related proteins, such as Ly-6A/E, Ly-6C, ThB, and CD59 antigens.

Amino Acid Sequence↗
PubMed1994

Simultaneous high-performance liquid chromatographic determination of 6 beta-hydroxycortisol and cortisol in urine with fluorescence detection and its application for estimating hepatic drug-metabolizing enzyme induction.

A simple and sensitive high-performance liquid chromatographic method is described for the simultaneous determination of 6 beta-hydroxycortisol (6 beta-OHF) and cortisol (F) in urine. Urine (1 ml) containing fludrocortisone as the internal standard is extracted with ethyl acetate. The extract is washed successively with sodium hydroxide solution and water, and subsequently dried under a stream of nitrogen. The residue is redissolved in methanol. The 6 beta-OHF, F and fludrocortisone in the methanol solution are oxidized by cupric acetate and the resulting glyoxal compounds are converted into fluorescent derivatives with 1,2-diamino-4,5-methylenedioxybenzene (DMB). The DMB derivatives of the corticosteroids are separated within 70 min on a reversed-phase column, L-Column ODS, using stepwise elution with methanol-acetonitrile-0.5 M ammonium acetate and detected fluorimetrically at 350 nm (excitation) and 390 nm (emission). The lower limits of detection for 6 beta-OHF and F are 1.8 pmol (680 pg) and 2.4 pmol (950 pg)/ml urine (0.6 pmol and 0.8 pmol/100 microliters injection volume), respectively, at a signal-to-noise ratio of 3. This method can be applied to the determination of urinary 6 beta-OHF, and the ratio of 6 beta-OHF to F in humans and in rhesus monkeys treated orally with phenobarbital as a hepatic drug-metabolizing enzyme inducer.

Administration, Oral↗
PubMed1994

Membrane proteins with molecular masses of 88, 90 and 150 kDa are responsible for binding of human immunoglobulin G Fc fragment to the native cells of Mycoplasma salivarium.

Mycoplasma salivarium cells bound the Fc fragment of human immunoglobulin G. The activity was remarkably enhanced by Mn2+, but not by Mg2+ and Ca2+; significantly inhibited by D-mannose; and reduced by pronase treatment of the cells. About 90% of the cells treated with pronase were not disrupted. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of proteins of the cells treated with pronase indicated that proteins with molecular masses of 88, 90 and 150 kDa (88 kp, 90 kp and 150 kp) were specifically digested. The results presented suggest that 88 kp, 90 kp and 150 kp, located in the outer surface of the cell membrane, are responsible for the activity of the M. salivarium cells and interact with a carbohydrate-containing moiety (D-mannose) of the Fc fragment in a Mn(2+)-dependent manner.

Bacterial Outer Membrane Proteins↗
PubMed1994

Role of active oxygen species in DNA damage by pentachlorophenol metabolites.

Pentachlorophenol (PCP) has been shown to be carcinogenic for mice, although it does not seem to be mutagenic in bacterial test systems. In this study, the mechanism of DNA damage by PCP metabolites in the presence of metals was investigated with a DNA sequencing technique using 32P-labeled DNA fragments and with an electrochemical detector coupled to an HPLC. The metabolite tetrachlorohydroquinone (TCHQ) caused DNA damage in the presence of Cu(II) but not in the presence of either Mn(II) or Fe(III). TCHQ plus Cu(II) frequently induced piperidine-labile sites at thymine residues and guanine residues. The most preferred sites were the thymine residues of the 5'-GTC-3' sequence. TCHQ increased 8-oxo-7,8-dihydro-2'-deoxyguanosine in calf thymus DNA in the presence of Cu(II). Typical OH scavengers showed no inhibitory effects on TCHQ- plus Cu(II)-induced DNA damage. Bathocuproine and catalase inhibited DNA damage, suggesting that Cu(I) and H2O2 have important roles in the production of active species causing DNA damage. Tetrachloro-p-benzoquinone (TCBQ) alone did not induce DNA damage in the presence of Cu(II), but addition of NADH induced DNA cleavage even in the absence of NADH-FMN oxidoreductase. UV-visible and ESR spectroscopies have demonstrated that TCHQ is rapidly autoxidized into semiquinone even in the absence of metal ions, indicating that the semiquinone radical itself is not the main active species inducing DNA damage. These results suggest that the semiquinone radical produced by the autoxidation of TCHQ and/or the reduction of TCBQ by NADH reacts with dioxygen to form superoxide and subsequently H2O2, which is activated by transition metals to cause DNA damage.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1994

Differential distribution of neurocalcin isoforms in rat spinal cord, dorsal root ganglia and muscle spindle.

The cellular distribution of neurocalcin isoforms in rat spinal cord, dorsal root ganglia and muscle spindle was examined using immunohistochemical techniques and two antibodies against different isoforms. In the study using the antibody against the purified neurocalcin from bovine brain, nerve fiber terminals and the cytoplasm of small-sized neurons in the posterior horn, some medium-sized neurons and numerous axons were strongly stained. In dorsal root ganglia, the cytoplasm of various-sized neurons, including about 40% of the total neurons, was also stained. Sensory nerve endings in muscle spindle were immunopositive. When the antibody against the expressed neurocalcin delta was applied, nuclei of the neurons were mainly stained in the spinal cord and dorsal root ganglion. The cytosol of glial cells but not axons in white matter showed neurocalcin delta-like immunoreactivity against the antibody. These findings suggest that each of the differently located isoforms may play a distinct role in Ca2+ signaling in sensory systems.

Amino Acid Sequence↗
PubMed1994

Identification of polysialic acid-containing glycoprotein in the jelly coat of sea urchin eggs. Occurrence of a novel type of polysialic acid structure.

Sea urchin eggs are surrounded by a gelatinous layer (called the jelly coat) that consists of mixture of fucoserich polysaccharides and sialic acid-rich glycoproteins. Chemical and 500 MHz 1H NMR spectroscopic studies revealed for the first time the presence of a novel polysialic acid (polySia) structure in the jelly coat glycoproteins isolated from Hemicentrotus pulcherrimus (designated polySia-gp(H)). The structure of the polySia chains was thoroughly characterized as (-->5-Oglycolyl-Neu5Gc alpha 2-->)n, where n ranges from 4 to more than 40 Neu5Gc residues. The polyNeu5Gc chains were attached to core oligosaccharides that were O-glycosidically linked to threonine residues on a core polypeptide. Each polypeptide contained about 17 O-linked polysialylglycan chains. The apparent molecular weight of polySia-gp(H) was 180,000. The expression of this new polySia structure in place of alpha 2-->8-linked polySia is the main structural feature that distinguishes polySia-gp from other known polysialylated glycoproteins. The (-->5-Ogly-colyl-Neu5Gc alpha 2-->)n chains were resistant to exo- and endosialidases from Arthrobacter ureafaciens and bacteriophage K1F, respectively. Discovery of these (-->5-Ogly-colyl-Neu5Gc alpha 2-->)n chains adds a new class of naturally occurring polySia to the structurally diverse family of polysialylated glycoproteins. The structure of a poly-Sia-gp from a different sea urchin species, Stronglyocentrotus purpuratus (designated polySia-gp(S)), was also determined to ascertain if there were any species-specific differences. The 500 MHz 1H NMR spectra of the two polySia-gps were identical, indicating that at this level of molecular detail the structures were the same. The molecular weight of polySiagp(S) was larger, however (250,000), and it contained about 25 polySia chains O-glycosidically linked to both threonine (two-thirds) and serine (one-third) residues.

Amino Acids↗
PubMed1994

Discovery of a new type of sialidase, "KDNase," which specifically hydrolyzes deaminoneuraminyl (3-deoxy-D-glycero-D-galacto-2-nonulosonic acid) but not N-acylneuraminyl linkages.

The release of 3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (KDN, deaminoneuraminic acid) residues from their alpha-ketosidic linkage is required to determine the structural and functional role of KDN-glycoconjugates in sources as disparate as trout egg polysialoglycoproteins and human cancers. We report for the first time the isolation and characterization of a novel type of sialidase (KDNase), which specifically hydrolyzes KDN ketosidic but not N-acylneuraminyl linkages. KDNase activity was assayed using 4-methylumbelliferyl KDN (4-MU-KDN). A KDNase-producing microorganism was identified as Sphingobacterium multivorum. The affinity-purified enzyme was designated KDNase SM to denote its origin and that it was free of N-acylneuraminidase, proteolytic, and other glycosidase activities. KDNase SM activity toward 4-MU-KDN was not inhibited by the N-acylneuraminidase inhibitor, 2,3-dehydro-2-deoxy-N-acetylneuraminic acid. KDNase SM released free KDN from naturally occurring substrates, including (KDN)GM3, KDN-glycoprotein, which bears a number of O-linked chains of KDN alpha 2-->3Gal beta 1-->3GalNAc alpha 1-->3 (KDN alpha 2-->(-->8KDN alpha 2-->)n-->6)GalNAc alpha 1-->, and the biantennary complex-type of N-glycan, KDN alpha 2-->3Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->6(KDN alpha 2-->3Gal beta 1-->4GlcNAc beta 1-->2Man alpha 1-->3)Man beta 1-->4GlcNAc beta 1-->4GlcNAc. KDNase SM thus exhibited a broad linkage specificity and was able to hydrolyze the KDN residues ketosidically linked alpha 2-->3, alpha 2-->6, and alpha 2-->8. The enzyme did not release Neu5Ac or Neu5Gc from 4-MU-Neu5Ac, N-acetyl-neuraminyllactose, colominic acid, or other Sia(Neu5Ac or Neu5Gc)-containing glycoconjugates.

Bacteria↗
PubMed1994

Thyroid diseases among atomic bomb survivors in Nagasaki.

OBJECTIVE: To elucidate the current thyroid disease status for the Nagasaki Adult Health Study cohort of the Radiation Effects Research Foundation. DESIGN: Survey study. SETTING: Nagasaki, Japan. PARTICIPANTS: Cohort members of the Nagasaki Adult Health Study who received biennial health examinations from October 1984 to April 1987 (n = 2856). A total of 2587 subjects remained after exclusion of persons exposed in Hiroshima or in utero and those who were not in Nagasaki at the time of the bombing. Thyroid radiation dose by the dosimetry system established in 1986 was available for 1978 of the 2587 subjects. MAIN OUTCOME MEASURES: Thyroid diseases were diagnosed using uniform procedures including ultrasonic scanning. The relationship of the prevalence of each thyroid disease with thyroid radiation dose, sex, and age was analyzed using logistic models. RESULTS: A significant dose-response relationship was observed for solid nodules, which include cancer, adenoma, adenomatous goiter, and nodules without histological diagnosis, and for antibody-positive spontaneous hypothyroidism (autoimmune hypothyroidism) but not for other diseases. The prevalence of solid nodules showed a monotonic dose-response relationship, yet that of autoimmune hypothyroidism displayed a concave dose-response relationship reaching a maximum (+/- SE) level of 0.7 +/- 0.2 Sv. CONCLUSIONS: The present study confirmed the results of previous studies by showing a significant increase in solid nodules with dose to the thyroid and demonstrated for the first time a significant increase in autoimmune disease among atomic bomb survivors. A concave dose-response relationship indicates the necessity for further studies on the effects of relatively low doses of radiation on thyroid disease.

Cohort Studies↗
PubMed1994

Isolation, structural determination, and calcium-binding properties of the major glycoprotein present in Bufo japonicus japonicus egg jelly.

Although the previous studies showed that the jelly coat is essential in anuran fertilization under natural conditions, identification and structural studies of the macromolecules that play functional roles have remained to be elucidated. In the present study we isolated acidic glycoproteins (JGP) from the solubilized egg jelly of Bufo japonicus japonicus, and showed that they were the major non-dialyzable macromolecular components of the jelly coat. JGP was a typical mucin-type glycoprotein, and it showed high degree of polydispersity in molecular masses ranging over 100-4000 kDa, but both amino acid and carbohydrate compositions were practically identical among fractions, suggesting that JGP was composed of a repeating glycoprotein unit. Four types of short O-glycan chains were isolated from JGP by reductive beta-elimination and their structures were determined as: Gal beta 1-->3[NeuAc alpha 2-->6]GalNAcol (= N-acetylgalactosaminitol), Fuc alpha 1-->2Gal beta 1-->3 [NeuAc alpha 2-->6]GalNAcol, Fuc alpha 1-->2Gal beta 1-->3[GlcNAc beta 1-->6]GalNAcol, and Fuc alpha 1-->2Gal beta 1-->3-GalNAcol. These carbohydrate units (about 80% of the mass of JGP) were linked to nearly all the serine and threonine residues which accounted for 55% of total amino acid residues. The Ca(2+)-binding property of JGP was studied by equilibrium dialysis. The high Ca(2+)-binding capacity of JGP was abolished by its desialylation of JGP and was highly dependent on the JGP concentration. When the low JGP concentrations as in the hydrated Bufo jelly were used, a 50% increment of both n (the number of binding sites) and Kd (the dissociation constant of JGP-Ca2+) values was observed. This property of JGP is suited to retaining Ca2+ and keeping its concentration at that just necessary for fertilizing sperm.

Animals↗
PubMed1994

Purification and enzymatic properties of peptide:N-glycanase from C3H mouse-derived L-929 fibroblast cells. Possible widespread occurrence of post-translational remodification of proteins by N-deglycosylation.

Recently, we found the occurrence of N-deglycosylating enzyme, peptide:N-glycanase (PNGase), in mammalian cells and observed that PNGase is a rather common enzyme involved in post-translational remodification of proteins (Suzuki, T., Seko, A., Kitajima, K., Inoue, Y., and Inoue, S. (1993) Biochem. Biophys. Res. Commun. 194, 1124-1130). We report here a 460-fold purification to homogeneity with 11.5% yield of PNGase from crude extract of C3H mouse-derived L-929 fibroblast cells. The purified enzyme, designated as L-929 PNGase, had the apparent molecular weight of 212,000 and was composed of two 105,000 subunits. Although this enzyme was capable of hydrolyzing structurally diverse natural glycopeptide substrates bearing high mannose, hybrid, and complex-type glycan units, the activity was completely inhibited by the presence of the fucose residue either alpha-1-->3- or alpha-1-->6-linked to the proximal GlcNAc residue. The enzyme showed maximal activity at pH near 7. This and the inability to act on glycoasparagine strongly support our view that this enzyme would not be involved in lysosomal degradation pathway. L-929 PNGase was characterized by having distinctly a low Km value, which may be of physiological significance. Possible wide occurrence of N-deglycosylation of glycoproteins was shown by a data bank survey of the protein sequences showing discrepancies between those determined directly (-D-X-(S/T)-) and those deduced from cDNA sequencing (-N-X-(S/T)-). We propose here that PNGase-catalyzed N-deglycosylation is a functionally important universal feature in living cells.

Amidohydrolases↗