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H Kosugi

Publications and source records attributed to H Kosugi.

At least 37 records · Page 2Linked to original sources
PubMed1995

Structure of the gene encoding the alpha subunit of the human interleukin 3 receptor.

Interleukin 3 is a cytokine that stimulates proliferation and differentiation of hematopoietic progenitor cells. Its receptor consists of two subunits, an interleukin 3-specific alpha subunit and a beta subunit shared by garanulocyte-macrophage colony stimulating factor and interleukin 5 receptors. In this paper, we determined the genomic structure of the alpha subunit of the human interleukin 3 receptor, which spans approximately 40 kb and has 12 exons. We found that the genomic structures of the alpha subunits of the human interleukin 3 and granulocyte-macrophage colony stimulating factor receptors are very similar. They possess a unique additional intron in the 'C domain', which is absent in the alpha subunit of the interleukin 5 receptor. These results suggest a shared evolutionary pathway of these two genes.

Base Sequence↗
PubMed1995

Gene structures of the alpha subunits of human IL-3 and granulocyte-macrophage colony-stimulating factor receptors: comparison with the cytokine receptor superfamily.

Recently, many genes encoding the members of the cytokine receptor superfamily (CRSF), which have common structural features, have been characterized. Analyses on the structures of the genes encoding the alpha subunits of human IL-3 (hIL-3R alpha) and granulocyte-macrophage colony-stimulating factor receptors (hGMR alpha) revealed that they have the structural features common to all members of the CRSF (i.e., conservation of the intron phase pattern as "1-2-1-0-1" rule in the fibronectin type III domains located in extracellular segments of type I cytokine receptor subunits. This finding led us to propose a possible model for gene evolution for the CRSF. We pointed out that the CRSF genes derived from a putative common ancestral gene. In addition to these common features, we found an additional intron that is unique to the IL-3R alpha and the GMR alpha genes. This additional intron suggests that the IL-3R alpha and the GMR alpha genes evolved closely in the evolution process of the CRSF genes. This evidence and results of recent studies on the evolution of mammalian X chromosome make it tempting to speculate that a putative common ancestral gene of the subfamily including IL-3R alpha, GMR alpha, and IL-5R alpha emerged in an autosome at least before the divergence of marsupials and eutherian mammals, early in the 200 million-year history of mammals.

Base Sequence↗
PubMed1995

Urinary excretion of thiobarbituric acid reactive substances of healthy subjects supplemented with a high dose of d-alpha-tocopherol.

The level of urinary thiobarbituric acid reactive substances (TBARS) consisting of bound forms of malonaldehyde and, to a lesser extent, other aldehydes is one of the indices of lipid peroxidation status. Levels of urinary TBARS in healthy subjects before and after supplementation with a high dose of d-alpha-tocopherol were measured using high performance liquid chromatography. Four healthy Japanese were given a supplement of 300 mg d-alpha-tocopherol/d, about 40-fold higher than the normal intake recommended, for a period of 50 d. Levels of urinary TBARS (nmol/kg body weight.h) within-day, before and after supplementation with d-alpha-tocopherol, exhibited similar behavior and levels of daily urinary TBARS (nmol/kg body weight.d) were unchanged by d-alpha-tocopherol supplementation. These results indicate that supplementation with a high dose of d-alpha-tocopherol does not affect the level of urinary TBARS.

Female↗
PubMed1994

Structure of the gene encoding the alpha subunit of the human granulocyte-macrophage colony stimulating factor receptor. Implications for the evolution of the cytokine receptor superfamily.

The receptor for granulocyte-macrophage colony-stimulating factor (GM-CSF) is composed of at least two subunits, alpha and beta. In addition to the conserved cysteine residues and a "WSxWS" motif, the extracellular segments of both subunits have domains that are structurally related to a fibronectin type III domain. This structure is conserved in all members of the cytokine receptor superfamily. We isolated and characterized genomic DNA clones containing the entire coding sequences of the alpha subunit of the human GM-CSF receptor (hGMR alpha). The gene spans approximately 44 kilobases and has 13 exons. The major transcription initiation site was determined to be 195 base pairs upstream of the translation initiation site. The putative promoter region lacks a typical TATA motif and an Sp1 binding site, but contains a purine-rich stretch about 30 base pairs upstream of the transcription initiation site. This stretch is also found in the human interleukin 2 receptor gamma subunit and granulocyte colony-stimulating factor receptor genes. We compared the exon-intron organization of the hGMR alpha gene with other members of the cytokine receptor superfamily and found the genomic organizations to be remarkably well conserved. On the basis of these observations, we propose a model for evolution of this gene family.

Base Sequence↗
PubMed1994

Variations in the level of urinary thiobarbituric acid reactant in healthy humans under different physiological conditions.

The level of urinary thiobarbituric acid (TBA) reactants in healthy human subjects due to malonaldehyde derivatives was measured to assess the lipid peroxidation status of the whole body. For each subject the TBA reactant level over a day varied over a 2-3 fold range while the daily level varied over a 1.5-3 fold range under normal life-style conditions. One of the factors causing an increase in the reactant level within a single day may be the subjects's physical activity, because the reactant level of each subject was higher in the afternoon or in the evening than in the morning. Remaining awake all night or hard exercise caused a dramatic increase in the reactant level over a day and in the daily reactant level. The reactant level within a single day for a subject was increased 5.5 fold and the daily level 3 fold by remaining awake all night, and the level within a day was increased 22 fold by hard exercise while the corresponding daily level was increased 7 fold. It is unlikely that food, alcohol and smoking greatly affect the reactant level. The results suggest that increased physical activity enhances lipid peroxidation in the whole body and thus the increased urinary excretion of malonaldehyde derivatives.

Adult↗
PubMed1993

Characteristics of the thiobarbituric acid reactivity of human urine as a possible consequence of lipid peroxidation.

A 532 nm red pigment formed in the thiobarbituric acid (TBA) assay of human urine was characterized after separation of the pigment by high-performance liquid chromatography. The yield of the red pigment was somewhat higher at pH 2 than at pH 5; its development was not inhibited by ethylenediaminetetraacetic acid. The characteristics of the pigment were similar to those of the pigment derived from standard malonaldehyde. The amount of the pigment formed was roughly equal to the content of malonaldehyde derivatives estimated as 1-(2,4-dinitrophenyl)pyrazole. Pigment formation was significantly enhanced by t-butyl hydroperoxide (t-BuOOH) and ferric ions, which may be due to pigment formed from aldehydes other than malonaldehyde; the presence of these aldehydes was confirmed by the formation of the corresponding 2,4-dinitrophenylhydrazones. The amount of pigment produced from 24-h urine samples of 12 healthy subjects was estimated to be 26-95 nmol/kg, and 65-182 nmol/kg in the presence of t-BuOOH. These values are lower than those for urine of rabbit or rat. The TBA reactivity in the absence and presence of t-BuOOH of human urine was not related to age or sex. The TBA reactivity of human urine collected in the afternoon and in the evening was higher than that of urine collected in the morning.

Animals↗
PubMed1992

Interpretation of the thiobarbituric acid reactivity of rat liver and brain homogenates in the presence of ferric ion and ethylenediaminetetraacetic acid.

The thiobarbituric acid (TBA) reactivity of rat liver and brain homogenates was characterized to elucidate what kinds of aldehyde species contributed to the reactivity. Characteristic pH dependence of the reactivity with a maximum at around pH 3 and marked enhancement of the reactivity by t-butyl hydroperoxide (t-BuOOH) and ferric ion were similar to those of alkadienals. The amounts of aldehyde species, including alkadienals determined as 2,4-dinitrophenylhydrazones, were high enough to account for the enhanced reactivity. The reactivity was inhibited by ethylenediaminetetraacetic acid (EDTA) but not completely, suggesting the presence of malonaldehyde whose reactivity was not affected by EDTA. The amounts of malonaldehyde determined as 1-(2,4-dinitrophenyl)pyrazole could account for a part of the reactivity in the presence of EDTA. Hence, the TBA reactivity of liver and brain homogenates at around pH 3 in the presence of t-BuOOH and ferric ion may be accounted for by alkadienals and malonaldehyde and that in the presence of EDTA by malonaldehyde.

Animals↗
PubMed1990

Is the thiobarbituric acid-reactivity of blood plasma specific to lipid peroxidation?

The fluorometric thiobarbituric acid (TBA) assay of blood plasma was performed under various conditions in order to assess whether the assay reflects lipid peroxidation. The TBA-reactivity of malonaldehyde was not dependent on the pH values of the reaction and was little affected by tert-butyl hydroperoxide (tert-BuOOH). The reactivity of 2,4-nonadienal and 2-hexenal, which was maximal at pH 3-4 and at above pH 4, respectively, was dramatically enhanced by tert-BuOOH and ferric ion, and suppressed by ethylenediaminetetraacetic acid (EDTA). The pigment formation from oxidized low-density-lipoprotein was maximal at about pH 5, markedly enhanced by ferric ion and suppressed by EDTA, indicating that the TBA-reactive substances in the oxidized lipoprotein were composed of malonaldehyde, alkadienals and alkenals originated from lipid peroxidation. The pigment formation from plasma and its phosphotungstic acid precipitate was maximal at pH 4 and at below pH 2, respectively. The effect of tert-BuOOH, ferric ion and EDTA was not significant. The major TBA-reactive substances from plasma may be compounds other than malonaldehyde, alkadienals, alkenals and those in the oxidized lipoprotein. The TBA-reactivity of plasma does not appear to be specific to lipid peroxidation.

Humans↗
PubMed1990

Major thiobarbituric acid-reactive substances of liver homogenate are alkadienals.

Thiobarbituric acid (TBA) assay of rat liver homogenate was performed by four general variations with 0.01% butylated hydroxytoluene. Development of red pigment was greatly dependent on the methods. The pigment formation by each method was dramatically increased by introduction of 2 mM t-butyl hydroperoxide (t-BuOOH). The pH values of the reaction mixtures greatly affected the pigment yield both in the absence and presence of t-BuOOH, and the maximal pigment yield was obtained at pH 3-4. These characteristic profiles of the pigment formation were similar to those from alkadienals and essentially different from those from malonaldehyde. Alkadienals were likely candidates for the TBA-reactive substances in the homogenate.

Aldehydes↗
PubMed1990

[Corrosion behavior of Ag-Pd binary alloys under dynamic conditions and its cytotoxicity (in vitro)].

Ag-Pd binary alloys with various palladium contents were extracted in Eagle's minimum essential medium by dynamic extraction at 200 rpm at 37 degrees C. The extracts were filtered through a 0.22 microns cellulose acetate filter, and the silver and palladium amount of the extracts and filtrates as dissolved metallic elements was measured with atomic absorption spectroscopy. Extracts and filtrates were also used in cultivation of L-929 cells to study in vitro cytotoxicity. An increase in the palladium content of the alloy resulted in decreased silver dissolution and increased palladium dissolution. The amount of palladium in the filtrates increased as the extraction period was extended, but the amount of silver was negligible in all filtrates. Extracts which had been extracted for 1 day showed strong cytotoxicity in pure Ag. However, the addition of palladium at a weight percent of more than 40% decreased cytotoxicity almost to the control level. Filtrate which had been extracted for 1 or 3 days was noncytotoxic in all alloys. However, the filtrate which had been extracted for 5 or 7 days showed cytotoxicity, which was especially strong in high-palladium alloys. These results demonstrate that extraction using a dynamic method appears to be useful in the investigation of their corrosion and biocompatibility.

Biocompatible Materials↗
PubMed1989

Potential thiobarbituric acid-reactive substances in peroxidized lipids.

This paper describes what components produce a red pigment in the thiobarbituric acid (TBA) test of peroxidized lipids. Alk-2-enals, alka-2,4-dienals and hydroperoxide functions are potential candidates for the red pigment in the TBA test. The TBA test can be regarded as an excellent method to reflect the combined effect of these components and thus the degree of lipid oxidation.

Aldehydes↗
PubMed1988

Elevated lead concentrations in Japanese ribs of the Edo era (300-120 BP).

Nineteen elements (Al, B, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, V and Zn) were analyzed in excavated bone (rib) of the Edo era (a Japanese historical era, 300-120 BP (before present] from different burial conditions in Tokyo, and in contemporary Japanese bone (rib) obtained from autopsy cases. The elemental composition of the excavated bones varied according to their burial conditions. The concentration of soil-related elements such as Fe, Mn, Co and Ti in the bone was lowest in the samples in the "wooden coffin in a stone room", next lowest in the "funeral urn with mud", and highest in the "wooden coffin full of mud". The Pb concentration was higher in excavated bones than in contemporary bones and much higher, by as much as several tens micrograms/g, in the bones in the "wooden coffin in a stone room" and in the "funeral urn with mud". These results strongly support the notion that Japanese in the city of Edo were highly polluted by environmental lead.

Bone and Bones↗
PubMed1987

Formation of yellow, orange, and red pigments in the reaction of alk-2-enals with 2-thiobarbituric acid.

The reaction of four to eight carbon straight-chain alk-2-enals with 2-thiobarbituric acid (TBA) produced yellow 455-nm-, orange 495-nm-, and red 532-nm-absorbing pigments depending upon the reaction conditions. The 1:1 reaction of the aldehydes with TBA in 15% acetic acid at 100 degrees C produced the yellow pigment at 0.25 h and the red at 6 h. The reaction of the aldehydes with TBA in excess at 100 degrees C produced the yellow at 0.25 h, the orange at 2-6 h, and the red at 0.25-6 h. The formation of these pigments required molecular oxygen. These pigments could be separated from each other on HPLC. The red pigment formed from the aldehydes could not be distinguished from the red 1:2 malonaldehyde-TBA adduct by absorption spectrum and HPLC. The red color yield was the highest in the 1:1 reaction and retarded in the reaction with TBA in excess. The red color due to these aldehydes may contribute in part to the color formed in the general TBA test of lipid oxidation. The 1:1 reaction initially produced colorless 1:1 adducts X, which were subsequently converted into the yellow and red pigments under aerobic conditions. The reaction of the aldehydes with TBA in excess might initially produce X and then another colorless 1:2 adducts Y; the latter being converted into yellow, orange, and red pigments under aerobic conditions.

Aldehydes↗
PubMed1986

Reaction of thiobarbituric acid with saturated aldehydes.

The reaction of thiobarbituric acid (TBA) with saturated aldehydes, i.e., 1-butanal, 1-hexanal and 1-heptanal, produced a 455-nm yellow and a 532-nm red pigment. Formation of the pigments depended on the reaction conditions. The yellow pigment was unstable in the presence of excess amounts of the saturated aldehydes. The red pigment was formed only when the reaction was performed at a TBA/aldehyde ratio of 1:1 in aqueous acetic acid. Formation of the yellow and red pigments required molecular oxygen. The colorless adducts, intermediates for the yellow and the red pigments, were isolated from the reaction mixtures. Aldol condensation and dehydration of 2 mol of the saturated aldehydes initially gave the alpha, beta-unsaturated aldehydes, which in turn reacted with TBA to form the colorless adducts, pyranopyrimidine derivatives. The adducts were then converted into the yellow and red pigments under aerobic conditions.

Aldehydes↗
PubMed1986

Elemental composition of ancient Japanese bones.

Excavated bones (rib) obtained from 50 sites in Japan were measured by ICP atomic emission spectrometry and atomic absorption spectrometry for concentration of 19 elements, including Al, B, Ca, Cd, Cr, Co, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, V and Zn. One hundred and forty-one specimens were classified into five groups according to Japanese prehistoric and historic eras (Jomon, Yayoi, Kofun, Kamakura and Muromachi, and Edo). The elements, with concentrations which showed no significant change with era were Al, B and Cr. Average concentrations of Ca were in the range 2-2.5 X 10(-1) g g-1 and those of P ranged from 1.1 to 1.3 X 10(-1) g g-1, indicating a well-preserved bone mineral matrix. The Ca/P ratio (mol/mol) was lowest in the Edo group--1.48 as compared with 1.54-1.66 in the other groups. Among the elements which showed changes with era were Pb, Fe, Co and Mn, all of which showed remarkably elevated concentrations in the Edo group. In addition to this unique elemental composition of Edo bones, samples from the Kofun era showed a completely different composition from those of other periods, i.e. they had the highest concentrations of Cd, Zn and Mg, and the lowest concentrations of Cu, K, Ni and Sr. The cause of the elevated Pb concentration in Edo bones is discussed in relation to human activities which may have led to environmental Pb pollution.

Bone and Bones↗