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Y Murata

Publications and source records attributed to Y Murata.

At least 19 recordsLinked to original sources
PubMed1992

[A case of chronic thyroiditis with transient painful thyroiditis occurring after the administration of lipiodol].

We reported a female case of painful thyroiditis occurring after hysterosalpingography and investigated whether the destructive thyroiditis was iodine-induced. The patient, aged 28, had TBG deficiency and the previous episode of thyrotoxicosis caused by Graves' disease. Lipiodol (containing 4.8g of iodide in 10ml solution) was administered via vagina for hysterosalpingography. One month after the radiography, serum inorganic iodide and Tg were elevated abnormally, but she was asymptomatic. After the subsequent 3 months she developed a painful and 3rd grade-sized goiter with concomitant marked elevation of thyroid hormones and inorganic iodide and also high titer of MCHA (320(2)X). A dramatic response was obtained with steroid. Thereafter she was treated with acupuncture on the thyroid gland, resulting in a sudden reappearance of tender goiter. This traumatic thyroiditis disappeared successfully in 2 weeks with steroid treatment. The painful thyroiditis subsided in 5 months throughout the course and she remained euthyroid for the ensuing 2 years. Aspiration biopsy was performed twice and revealed lymphocytic thyroiditis. Values of serum Tg varied in good correlation with those of serum inorganic iodide or rT3 throughout the course, respectively (P < 0.01, P < 0.05). Significant correlations between FT4 and FT3, and also T4 and T3 were observed, respectively (P < 0.01, P < 0.05). Serum inorganic iodide was elevated to 316 micrograms/dl at the symptomatic stage of the thyroiditis and decreased to 170 micrograms/dl at the resolving phase 2 months after the inflammation. Iodide disappearance curve showed a diphasic slope. The BHL was calculated as 60.3 days during the symptomatic stage and 6.9 months in euthyroid state.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Molecular species analysis of a product of phospholipase D activation. Phosphatidylethanol is formed from phosphatidylcholine in phorbol ester- and bradykinin-stimulated PC12 cells.

Tumor-promoting phorbol esters or calcium-mobilizing receptor ligands stimulate phosphatidylcholine breakdown and in many cells this is accompanied by phospholipase D (PLD) activation. We tested whether or not a direct relationship exists between these two phenomena. Pheochromocytoma (PC12) cells were stimulated with the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate or with the calcium-mobilizing receptor ligand bradykinin in media containing 1% ethanol. The fatty acid composition of the molecular species of phosphatidylethanol (PEt), a product of PLD activation, formed in stimulated cells was compared with the molecular species of endogenous phospholipids isolated from unstimulated PC12 cells. PEt was isolated and analyzed by fast atom bombardment-mass spectrometry (FAB-MS) in the negative ion mode. Fatty acid composition and headgroup structure of the major PEt molecular ions were confirmed by linked scan analysis. Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol were isolated from unstimulated cells and converted into phosphatidic acids using PLD. Mass spectra of the respective phosphatidic acids were obtained by fast atom bombardment-mass spectrometry as described above. The molecular species of PEt formed in 12-O-tetradecanoylphorbol-13-acetate- and bradykinin-stimulated PC12 cell were identical to those of phosphatidylcholine isolated from untreated cells.

Animals↗
PubMed1992

[Urinary iodide excretion in Japanese people and thyroid dysfunction].

In order to assess the Japanese dietary iodine intake, we examined the urinary iodine excretion of those on an ordinary Japanese diet chosen at random and observed whether the thyroid function might affect the amounts of urinary iodine excretion. The subjects consisted of cases of untreated hypothyroidism and chronic thyroiditis (CT) and euthyroid controls who were healthy people or had non-thyroidal disorders such as diabetes mellitus or hypertension. Eight cases of hypothyroidism were composed of 3 cases of secondary hypothyroidism with empty sella syndrome and 5 cases of primary hypothyroidism and 32 patients with CT have been maintained in euthyroid states with T4 medication. We selected 32 cases of sex and age-matched healthy people as controls. The mean levels of excreted urinary iodine were 465.6 micrograms/day in the healthy controls and 471.8 micrograms/day in patients with CT, respectively. Urinary iodine excretion was significantly correlated to serum inorganic iodide in both controls and CT patients, of which correlation coefficients were +0.35 and +0.5, respectively. Urinary iodine and serum inorganic iodide ratios (U/S) in hypothyroidism were significantly (p less than 0.05) depressed compared with those in CT. The present study indicated that recent Japanese dietary iodine intake was estimated to be approximately 470 micrograms/day and that the urinary iodine excretion would be influenced not only by iodine intake but also by thyroid function.

Adult↗
PubMed1992

Bis(monoacylglycero)phosphate from PC12 cells, a phospholipid that can comigrate with phosphatidic acid: molecular species analysis by fast atom bombardment mass spectrometry.

Phospholipids from pheochromocytoma (PC12) cells were purified by one-dimensional thin-layer chromatography (TLC). Material corresponding in RF to phosphatidic acid (PA) was analyzed by fast atom bombardment mass spectrometry (FAB). The molecular ions of the major constituents corresponded in mass to phosphatidylglycerols (PG), which, however, have a lower RF value. Analysis of the mass spectra demonstrated that this material consists of bis(monoacylglycero)phosphates (BMP, lysobisphosphatidic acid), a structural isomers of PG. Linked scans of individual molecular ions indicate that BMP from PC12 cells is esterified almost exclusively with monounsaturated (16:1 and 18:1) and polyunsaturated (20:4 and 22:6) fatty acids. One of the two major molecular species contains two monounsaturated (18:1/18:1), while the other contains both a monounsaturated (18:1) and a polyunsaturated (22:6) fatty acid ester. FAB in combination with TLC is ideally suited for analysis of molecular species of phospholipids.

Animals↗
PubMed1992

Glucose and oxygen deprivation induces a Ca(2+)-mediated decrease in (Na(+)+K+)-ATPase activity in rat brain slices.

Exposure of rat brain cortical slices to a medium lacking in glucose, oxygen or both glucose and oxygen, resulted in a decrease of the tissue ATP content and a reduction of (Na(+)+K+)-ATPase activity in membranes prepared from the slices. These treatments also inhibited partial reactions of (Na(+)+K+)-ATPase such as Na(+)-dependent phosphorylation and K(+)-stimulated phosphatase, as well as specific binding of [3H]ouabain in membranes prepared from the slices. Glucose deprivation and hypoxia decreased (Na(+)+K+)-ATPase activity in the absence of extracellular Ca2+, but the effects were blocked by 1,2-bis(2-amino-phenoxy)ethane-N,N,N',N'-tetraacetic acid tetra-acetomethyl ester (BAPTA-AM), a chelator of intracellular Ca2+. Metabolic inhibitors mimicked the effects of glucose deprivation and hypoxia. The effect of glucose-free hypoxia was dependent on extracellular Ca2+. It was blocked by Mg2+ at high concentration, bepridil or amiloride, but not by voltage-sensitive Ca2+ channel antagonists and glutamate receptor antagonists. None of the drugs tested here, except for dithiothreitol, affected the inhibitory effect of glucose-free hypoxia on the enzyme activity. In contrast to brain (Na(+)+K+)-ATPase, the kidney enzyme was insensitive to glucose and oxygen deprivation and metabolic inhibitors which depleted the tissue ATP.

Animals↗
PubMed1992

[The functional outcome of patients with subacute thyroiditis].

Whether with the passage of time subacute thyroiditis leads to hypothyroidism remains to be determined. Therefore, we evaluated the thyroid function including TRH test of 66 patients with a previous history of subacute thyroiditis and age-matched control subjects with special reference to the measurement of inorganic iodide. The patients were divided into 3 groups according to time lapse since the occurrence. Group 1 consisted of 24 cases followed up for 4 to 24 months. Sixteen cases in group 2 had their courses from 2 to 5 years, and group 3 was composed of 26 cases over the past 5 to 30 years. We selected 169 subjects without history of subacute thyroiditis and divided them into three control groups matched for age, each corresponding to the patient groups (group 1a, 2b and 3c, respectively). 41.7% and 29.2% of cases in group 1 had high basal levels of serum TSH (greater than 3.6 microU/ml) and delta TSH (the increment of TSH after TRH, greater than 46.8 microU/ml). In group 2, levels of serum T3 and T4 returned to normal ranges. However, in group 3, significant higher elevations in TSH and delta TSH than those in group 3c were observed, and the T4, FT4, T3 and FT3 levels were lower than those of group 3c (p less than 0.01 and p less than 0.05, respectively). 42.3% of cases in group 3 showed high TSH, and there were 4 cases with clinical hypothyroidism. Among the cases studied, a significant negative correlation (p less than 0.01) between levels of TSH and T4 was observed, while a correlation between TSH and delta TSH was positive (p less than 0.001). High levels of serum inorganic iodide were observed in 6.1% of cases and a correlation between inorganic iodide and TSH was significantly positive (p less than 0.01) not only in patients with subacute thyroiditis, but also in the control subjects. Antithyroid autoantibodies were detected in 42.4% of all the cases with subacute thyroiditis and also in 45.6% of all the controls. In group 3, MCHA was detected in 64.5% of the cases, and the frequency was higher than that of group 3c as well as that of 25% in group 2 (p less than 0.01), respectively. In 15.4% of the cases in group 3, the titers of MCHA were more than 40(2), and the titers of MCHA were significantly higher in patients with a long-term period after the onset of subacute thyroiditis than those with a short-term period.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1992

Synthesis of nigero-oligosaccharides.

Nigerose [alpha-D-Glcp-(1----3)-D-Glcp], nigerotriose, nigerotetraose, and nigeropentaose have been synthesized by chain elongation starting at the reducing end, from the corresponding octa-, undeca-, tetradeca-, and heptadeca-beta-D-acetates, respectively, via thioglycoside-mediated 1,2-cis coupling, using 1,2,4,6-tetra-O-acetyl-beta-D-glucopyranose as the glucosyl acceptor and methyl 2,3,4,6-tetra-O-benzyl-1-thio-beta-D-glucopyranoside, methyl 3-O-allyl-2,4,6-tri-O-benzyl-1-thio-beta-D-glucopyranoside, and methyl O-(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1----3)-2,4,6-tri-O- benzyl-1-thio-beta-D-glucopyranoside as the donors.

Carbohydrate Sequence↗
PubMed1992

Molecular cloning and expression of the human interleukin 5 receptor.

Human interleukin 5 (IL-5) plays an important role in proliferation and differentiation of human eosinophils. We report the isolation of cDNA clones from cDNA libraries of human eosinophils by using murine IL-5 receptor alpha chain cDNA as a probe. Analysis of the predicted amino acid sequence indicated that the human IL-5 receptor has approximately 70% amino acid sequence homology with the murine IL-5 receptor and retains features common to the cytokine receptor superfamily. One cDNA clone encodes a glycoprotein of 420 amino acids (Mr 47,670) with an NH2-terminal hydrophobic region (20 amino acids), a glycosylated extracellular domain (324 amino acids), a transmembrane domain (21 amino acids), and a cytoplasmic domain (55 amino acids). Another cDNA encodes only the extracellular domain of this receptor molecule. Other cDNA clones encode molecules having diversified cytoplasmic domains. COS7 cells transfected with the cDNA expressed a approximately 60-kD protein and bound IL-5 with a single class of affinity (Kd = 250-590 pM). The Kd values were similar to that observed in normal human eosinophils. In contrast to the murine 60-kD alpha chain, which binds IL-5 with low affinity (Kd = approximately 10 nM), the human alpha chain homologue can bind IL-5 with much higher affinity by itself. RNA blot analysis of human cells demonstrated two transcripts (approximately 5.3 and 1.4 kb). Both of them were expressed in normal human eosinophils and in erythroleukemic cell line TF-1, which responds to IL-5. The human IL-5 receptor characterized in this paper is essential for signal transduction, because expression of this molecule in murine IL-3-dependent cell line FDC-P1 allowed these cells to proliferate in response to IL-5.

Amino Acid Sequence↗
PubMed1992

Evidence that hepatocytes can phagocytize exogenous substances.

Although the phagocytic action of Kupffer cells is well known, such a phenomenon has not been well documented for hepatocytes. Following the injection of a suspension of egg lecithin-coated silicon particles (0.5-1.5 microns in diameter) into the portal vein of rats, Kupffer cells showed minimal phagocytotic action, which was in contrast to the hepatocytes which displayed numerous phagocytized silicon particles. By comparison, when noncoated silicon particles of the same diameter as those that were coated were injected into the portal vein, the opposite observation was made. There was no uniformity in the ability of the hepatocytes to phagocytize either coated or noncoated particles from one lobule to another. Some showed active phagocytosis, while in others no evidence of such a process was observed. These data provide strong evidence for the selective phagocytic action of liver hepatocytes.

Animals↗
PubMed1992

Functional role of self IA molecules in polyclonal B cell activation using an autoreactive B cell clone derived from (NZB X NZW) F1 mice.

The mechanism of polyclonal B cell activation in autoimmune diseases was investigated by using an autoreactive B cell clone established by somatic hybridization with B cells derived from NZB X NZW (B/W) F1 mice. Briefly, splenic B cells from B/W F1 mice were fused with M12.4.1, a mutant of a B cell line, in the presence of polyethylene glycol and DMSO. NW47.7, a subclone of a resulting hybridoma, expresses B cell surface antigens on the cell membrane, namely IAd, IgM, B220, the receptors for the C3 fragment of complement (C3R), and the Fc portion of IgG (Fc gamma R). It also possesses a receptor molecule for mouse red blood cells treated with bromelain (Br-MRBC) on its surface, by rosette-forming assay with Br-MRBC. In contrast, parental M12.4.1 does not express IAd and IgM on the cell membrane, and does not bind to Br-MRBC under the same conditions. Thus, it is likely that NW47.7 may be an autoreactive B cell clone specific for Br-MRBC. Interestingly, NW47.7 was induced to generate a significant number of IgM-secreting cells when treated with Br-MRBC and rIL-5. Furthermore, mAb against IAd molecules, but not IAk and KdDd, markedly inhibited the differentiative effect of polyclonal activators such as LPS and rIL-5. Also, when MHC identical irradiated B cells were added to the culture of NW47.7 as a stimulator, the induction of IgM-producing cells was greatly augmented, but this augmenting effect was lost by interfering with direct contact of NW47.7 cells with stimulator B cells using a semipermeable membrane, as well as by the addition of mAb against IAd molecules. In addition, irradiated NW47.7, but not M12.4.1, by itself could enhance the secretion of IgM by NW47.7 as a stimulator, but this enhancing effect markedly decreased in the presence of anti-IAd mAb. The present results suggest that surface IA molecules on B cells are involved during the differentiative response to polyclonal activators, and may directly provide a differentiative signal for maturation of B cells into IgM-secreting cells.

Animals↗
PubMed1992

Immunohistochemical localization of Na,K-ATPase in the in situ lens, cultured human lens epithelium and lentoid.

The localization of Na,K-ATPase in the lens is quite controversial. We explored this problem through immunoelectron microscopic examination of rat and human lens. Unlike previously reported results, we have found that Na,K-ATPase is localized in the basal plasma membrane, but not in the lateral or apical plasma membrane of both rat and human lens epithelium. The lens fiber lacked immunoreaction. Localization of Na,K-ATPase was also investigated in the cultured human lens epithelium and in lentoid. Immunoreaction was detected in the apical (facing the media) plasma membrane of the lens epithelium cultured on the lens capsule, whereas the reaction was observable in both apical and basal plasma membrane of the lens epithelium cultured on the biopore membrane filters. Immunoreaction in lentoid was observed in the surface plasma membrane. These data indicate that the polarized distribution seen in the in situ lens epithelium changes when these cells are cultured, and that Na,K-ATPase in the cultured lens cells including lentoid is located in the plasma membrane which is in contact with the growth media. This change in polarity of Na,K-ATPase distribution in cultured epithelial cells may be dictated by the need to maintain ion homeostasis by extrusion of sodium ions across the cell membrane facing the media.

Animals↗
PubMed1992

The influence of surface conditions and silane agents on the bond of resin to dental porcelain.

The influence of porcelain surface condition and the application of silane agents on the adhesion between resin and dental porcelain were investigated. The experimental variables included three porcelain surface preparations, as polished, etched with phosphoric acid, or etched with hydrofluoric acid and three kinds of commercially available silane coupling agents. The shear bond strength between the light-cured composite and the dental porcelain was measured after one-day immersion in 37 degrees C water. Samples without the silane agent application were also tested as controls. Without the silane agent, hydrofluoric acid-etched specimens had a higher bond strength than polished or phosphoric acid-etched specimens. The combination of hydrofluoric acid-etching and an application of Cosmotech Porcelain Primer increased the bond strengths more than that of phosphoric acid-etching. With the application of Laminabond Porcelain Primer or Optec Silane Coupling Agent, high bond strengths were obtained regardless of the porcelain surface condition. Therefore, it seems the chemical reactions between the porcelain surface and silane agents were responsible for the high shear bond strengths.

Acid Etching, Dental↗
PubMed1992

Immunoelectronmicroscopic differentiation of linear IgA bullous dermatosis of adults with coexistence of IgA and IgG deposition from bullous pemphigoid.

BACKGROUND: The differentiation between linear IgA bullous dermatosis (LABD) and bullous pemphigoid (BP) is sometimes difficult in patients who have both IgA and IgG deposition in a linear pattern at the basement membrane zone. OBJECTIVE: We address whether two cases of acquired subepidermal blistering disease with coexistence of IgA and IgG deposition in a linear pattern at the basement membrane zone are LABD or BP. METHODS: The two cases were investigated by immunoelectron microscopy and compared with two typical cases of LABD. RESULTS: In both cases, the deposition of IgA and IgG was ultrastructurally localized below the lamina densa in close association with anchoring fibrils, as was seen in two cases of typical LABD. CONCLUSION: These findings indicate that our two cases of acquired blistering disease with co-existence of IgA and IgG deposition are LABD, rather than BP.

Aged↗
PubMed1992

Autonomic nervous system regulation of baseline heart rate in the fetal lamb.

OBJECTIVE: We examined 29 chronically instrumented fetal lambs from 125 to 143 days' gestation to investigate the effects of fetal behavioral states and autonomic nervous system maturation on baseline fetal heart rate. STUDY DESIGN: Behavioral states were defined from electrocorticographic analysis as low-voltage fast activity or high-voltage slow activity. Decrease and increase in baseline fetal heart rate subsequent to administration of propranolol and methylatropine represented beta-sympathetic and parasympathetic activity. RESULTS: Baseline fetal heart rate decreased with gestation in both states, with steeper regression in low-voltage fast activity (p less than 0.001). Positive correlation was noted between gestational age and percent decrease baseline fetal heart rate in both states with steeper regression in high-voltage slow activity (p less than 0.001), and between gestational age and percent increase baseline fetal heart rate with steeper regression in low-voltage fast activity (p less than 0.001). Fetal heart rate beta-sympathetic and parasympathetic tones increased with age in both states, with elevation of beta-sympathetic tone in high-voltage slow activity and parasympathetic tone in low-voltage fast activity. CONCLUSION: Sympathetic and parasympathetic systems influence baseline fetal heart rate in these behavioral states and with age.

Animals↗
PubMed1992

Physiologic baroreceptor activity in the fetal lamb.

OBJECTIVE: We investigated the influences of gestational age and behavioral state on fetal baroreceptor activity. STUDY DESIGN: Two protocols were used to analyze low-voltage fast activity and high-voltage slow activity in eight chronically instrumented ovine fetuses at days 127 to 142. In protocol 1 correction of fetal heart rate to mean arterial blood pressure was assessed under physiologic conditions, and the linear regression slope of fetal heart rate on mean arterial pressure was calculated. In protocol 2 an injection of 7.5 micrograms of norepinephrine was given during consecutive behavioral cycles. The ratio of fetal heart rate decrease to mean arterial pressure increase was determined as representing baroreceptor activity. RESULTS: Under protocol 1 the slope was steeper in high-voltage slow activity (2.33 +/- 1.03) than in low-voltage fast activity (0.89 +/- 0.37) (n = 21, p less than 0.001), indicating that fetal heart rate changes are sensitive to blood pressure changes during high-voltage slow activity. Under protocol 2 inverse relationships were found between the ratio of fetal heart rate decrease to mean arterial pressure increase and gestational age in low-voltage fast activity and high-voltage slow activity. CONCLUSION: Fetal baroreceptor activity increased during high-voltage slow activity and decreased with gestational age.

Animals↗
PubMed1992

Localization of the gene encoding the alpha subunit of human interleukin-5 receptor (IL5RA) to chromosome region 3p24-3p26.

The chromosomal location of the human gene for the alpha subunit of interleukin-5 receptor (IL5RA) has been determined. The human IL5RA gene was localized to the short arm of chromosome 3 by Southern blot analysis of DNA from a panel of mouse-human hybrid somatic cell lines. The IL5RA gene has been further localized to human chromosome region 3p24-3p26 by in situ hybridization of a molecularly cloned IL5RA cDNA fragment to metaphase chromosomes. The results suggest that the IL5RA locus is unlinked to other members of the hematopoietic receptor family. Assignment of the IL5RA gene to chromosome 3 at bands p26-p24 raises the possibility that it may be altered by certain nonrandom chromosomal abnormalities arising in human hematopoietic malignancies and solid tumors.

Animals↗
PubMed1992

Ultrastructural analysis of pulmonary alveolar proteinosis induced by methylnaphthalene in mice.

Pulmonary alveolar proteinosis was induced at a 100% incidence in B6C3F1 female mice by twice weekly painting the back skin with methylnaphthalene for 30 weeks to give a total dose of 7.14 g/kg b.wt. Semithin sections were used for defining areas of type II pneumocyte hyperplasia and hypertrophy and associated proteinosis. Ultrastructurally, alveolar spaces were found to be filled with numerous myelinoid structures resembling the lamellar bodies of type II pneumocytes. Mononucleated giant cells (balloon cells, BC) containing numerous myelinoid structures, lipid droplets and many electron dense amorphous ascicular crystals were closely associated with this extracellular membranous material. Stacks of elastic fibers stained with tannic acid and bundles of collagen fibers were loose and discontinuous in the interstitium of affected areas. The following pathogenesis is hypothesized: type II pneumocytes produce increased amounts of lamellar bodies due to their hyperplasia and hypertrophy and develop to form BC which liberate numerous myelinoid structures on their rupture. Epidermal absorption of methylnaphthalene is an efficient reliable method of induction of this internal disease.

Animals↗