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T Sone

Publications and source records attributed to T Sone.

At least 145 records · Page 8Linked to original sources
PubMed1991

Quantitative estimation of infarct size by simultaneous dual radionuclide single photon emission computed tomography: comparison with peak serum creatine kinase activity.

To test the hypothesis that simultaneous dual energy single photon emission computed tomography (SPECT) with technetium-99m (99mTc) pyrophosphate and thallium-201 (201TI) can provide an accurate estimate of the size of myocardial infarction and to assess the correlation between infarct size and peak serum creatine kinase activity, 165 patients with acute myocardial infarction underwent SPECT 3.2 +/- 1.3 (SD) days after the onset of acute myocardial infarction. In the present study, the difference in the intensity of 99mTc-pyrophosphate accumulation was assumed to be attributable to difference in the volume of infarcted myocardium, and the infarct volume was corrected by the ratio of the myocardial activity to the osseous activity to quantify the intensity of 99mTc-pyrophosphate accumulation. The correlation of measured infarct volume with peak serum creatine kinase activity was significant (r = 0.60, p less than 0.01). There was also a significant linear correlation between the corrected infarct volume and peak serum creatine kinase activity (r = 0.71, p less than 0.01). Subgroup analysis showed a high correlation between corrected volume and peak creatine kinase activity in patients with anterior infarctions (r = 0.75, p less than 0.01) but a poor correlation in patients with inferior or posterior infarctions (r = 0.50, p less than 0.01). In both the early reperfusion and the no reperfusion groups, a good correlation was found between corrected infarct volume and peak serum creatine kinase activity (r = 0.76 and r = 0.76, respectively; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical Enzyme Tests↗
PubMed1991

Immunomodulator, LZ-8, prevents antibody production in mice.

LZ-8, a new and recently discovered immunomodulator from Ganoderma lucidum, has been shown to have immunosuppressive activity in vivo and to be a member of the immunoglobulin superfamily. In this paper we examined the in vivo effect of LZ-8 on antibody production using the hepatitis B surface antigen (HBs Ag) in mice. LZ-8 had mitogenic activity in vitro towards spleen cells of C57BL/10 (B10) and C57BL/10BR (B10BR) as previously shown towards those of DBA/2 mice. B10 and B10BR mice produced anti-HBs Ag antibody by the twice sensitization of the antigen while intraperitoneal administration of LZ-8 twice weekly into the mice (8 and 12 mg/kg) greatly prevented the production of antibody to HBs Ag (83.3-96.8% inhibition). We further examined the effect of LZ-8 administration on mitogen responsibility of spleen cells and on the T-cell subset population in both the spleen and lymph node but no significant differences were observed between the LZ-8 treated and untreated mice. These results suggest that the immunosuppressive activities of LZ-8, previously shown, such as the prevention of systemic anaphylaxis and the Arthus reactions, were caused by the blocking of antigen-specific antibody production.

Adjuvants, Immunologic↗
PubMed1991

Regulation of metallothionein production in HeLa cells.

Metallothioneins are cysteine-rich, heavy-metal-binding proteins which have been assumed to participate in the detoxification of toxic metals. The mechanism of thionein (apoprotein of metallothionein) induction by cadmium was studied using cultured human cells. It was found that when thionein synthesis reaches a maximum (6-8 h after induction), it no longer responds to additional cadmium. Changes in cadmium uptake or induction of inhibitory proteins were not responsible. Together with our previous findings, a possible mechanism is proposed: loss of the secondary induction response might be due to increased intracellular levels of thionein, which has been overproduced by the initial induction.

Cadmium↗
PubMed1991

Acetylation of 2-aminofluorene derivatives by dog hepatic microsomes.

Dog urinary bladder is a target organ of carcinogenic arylamines. However, dog hepatic and urothelial cytosols lack acetylation enzymes that are capable of activating N-hydroxy metabolites of arylamines, suggesting that other enzymes may be involved. In the present study, we found that dog liver microsomes were capable of N-acetylation of 2-aminofluorene and N,O-acetyltransfer of N-hydroxy-2-acetylaminofluorene (N-OH-AAF), and that these activities were inhibited by paraoxon. The 0.25% Triton X-100 extractable fraction of microsomes was resolved on an ion-exchange column into three different proteins that retained these activities. Two of these proteins, designated as enzyme I and enzyme II, were further chromatographed on a Sephacryl S-300 column. As judged from the gel filtration profile, the mol. wt of enzyme I was approximately 180 kDa and that of enzyme II was greater than 700 kDa. SDS-PAGE analysis showed that the subunit weight of enzyme II was approximately 150 kDa. In addition to N-acetylation of 2-aminofluorene and N,O-acetyltransfer of N-OH-AAF, these three enzymes were capable of the deacetylation of 2-acetylaminofluorene, N-OH-AAF and 4-nitrophenyl acetate. The ability of these microsomal enzymes to activate N-hydroxylated aromatic amines and the presence of these enzymes in urothelial cells, reported previously, suggests that they may play an etiological role in the carcinogenicity of these agents in the dog.

2-Acetylaminofluorene↗
PubMed1991

On the transforming growth factor beta-like activity of synthetic polypeptides comprising the amino-terminal sequence of human parathyroid hormone-related peptide.

Purified native forms of human parathyroid hormone-related peptide (PTHrp) have recently been reported to display biological activities characteristic of transforming growth factor beta (TGF-beta). The TGF-beta-like property of PTHrp may reside within the amino N-terminal PTH-receptor binding region of the polypeptide, since a synthetic analog corresponding to amino acids 1-36 of human PTHrp is as active as purified native PTHrp in bioassays specific to TGF-beta. Complete lack of structural similarity between PTHrp and TGF-beta prompted us to address the question whether copresence of the TGF-beta-like and PTH-like biological activities in the N-terminal sequence of the PTHrp molecule is a general phenomenon observable with different N-terminal PTHrp peptides of varying amino acid chain length in a variety of target cells that respond in defined ways to TGF-beta in vitro. Two forms of synthetic N-terminal human PTHrp, PTHrp-(1-34) and [Tyr40]PTHrp-(1-40), which are fully active in conventional assays for PTH/PTHrp, were tested for effects in three in vitro bioassay systems for TGF-beta: 1) stimulation, and 2) inhibition, respectively, of epidermal growth factor-dependent soft-agar colony formation of either normal rat kidney-derived fibroblasts (NRK 49F) or human lung carcinoma cells (A549); and 3) biosynthesis of metabolically labeled fibronectin in both NRK 49F cells and clonal osteoblastic rat osteosarcoma cells (ROS 17/2.8). Human TGF-beta over the dose range of 2.5-80 pM significantly stimulated or inhibited soft-agar colony formation of either NRK 49F or A549 cells, respectively, and caused a severalfold increase in biosynthetically labeled [35S]fibronectin in NRK 49F and ROS 17/2.8 cells. In contrast, none of PTHrp-(1-34), [Tyr40]PTHrp-(1-40), and synthetic human PTH-(1-34), each tested at 0.1-10 nM, displayed detectable biological activity in any of the three assay systems. In addition, covalent cross-linking of intact NRK 49F and ROS 17/2.8 cells with either [125I]TGF-beta or 125I-[Tyr40] PTHrp-(1-40) revealed the presence of several distinct affinity-labeled receptor species for TGF-beta in both cell types and the 80K PTH/PTHrp receptors in ROS 17/2.8 cells. The affinity-labeled TGF-beta receptor species were insensitive to excess PTHrp and PTH peptides, and the 80K PTH/PTHrp receptors were insensitive to excess TGF-beta, indicating that PTHrp and TGF-beta do not cross-react with respect to receptor binding for interaction with these cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Affinity Labels↗
PubMed1991

A 55-kilodalton accessory factor facilitates vitamin D receptor DNA binding.

The interaction of the vitamin D receptor with a vitamin D-responsive element (VDRE) derived from the human osteocalcin promoter in vitro has been shown to require a nuclear accessory factor (NAF) derived from monkey kidney cells. In this report we show that this factor is widely distributed in cells and tissues, including those that do not express the vitamin D receptor (VDR). NAF is required for VDR binding to a variety of known VDREs. VDR and NAF independently bind the VDRE weakly, as assessed by elution profiles generated during VDRE affinity chromatography. Together, however, both proteins coelute from this column with a profile that indicates a tighter strength of interaction. Analogous chromatography of the VDR derived from ROS 17/2.8 cells treated with 1,25-dihydroxyvitamin D3 in culture also reveals a dual profile of weak and strong binding, suggesting that in vivo modifications are unlikely to alter receptor DNA binding. NAF is a protein of 55 kDa, as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and cross-linking experiments suggest that the VDR and NAF together form a heterodimer on a single VDRE with a mol wt of 103 kDa. These data demonstrate that NAF is required for VDR binding to specific DNA in vitro and suggest the possibility that NAF may be required for the transactivation capability of the VDR in vivo.

Animals↗
PubMed1991

Clinical study of the stunned myocardium.

Clinical features of 37 cases of stunned myocardium were studied. Mean duration of asynergy was 22.6 +/- 15.7 days. In all 11 cases of unstable angina without any significant serum creatine kinase leakage, the duration of asynergy was within 14 days. Related coronary lesions were reperfused (spontaneously or by interventional therapy) to TIMI grade II or higher. Transient Q waves were observed in 39% of all cases. Negative T waves tended to be prolonged, and persisted after disappearance of asynergy in 74% of all cases. 201Tl uptake in the stunned area varied widely between individual cases (ranging from "absent" to "normal"), although it became normal in all cases in the chronic stage. Mal-distribution of 99mTc-pyrophosphate (PYP) to the endocardial side of the stunned area was observed in 33%. In 186 cases of acute coronary syndrome, we studied whether or not reversibility of ischemia-disturbed myocardium could be predicted by simultaneous dual isotope SPECT, and found that 201Tl-uptake in the chronic stage significantly improved in the region showing absence of 99mTc-PYP accumulation or maldistribution of 99mTc-PYP to the endocardial side, while reversibility of the region showing transmural 99mTc-PYP accumulation and a dought pattern was poor. Ischemia-associated myocardial damage recovered to various degrees, and dual isotope SPECT was useful in evaluating the reversibility of such damage already at the acute stage.

Adult↗
PubMed1991

A unique mutation in the vitamin D receptor gene in three Japanese patients with vitamin D-dependent rickets type II: utility of single-strand conformation polymorphism analysis for heterozygous carrier detection.

Vitamin D-dependent rickets type II is a hereditary disease resulting from a defective vitamin D receptor. In three Japanese patients with vitamin D-dependent rickets type II whose fibroblasts displayed normal cytosol binding and impaired nuclear uptake of 1,25-dihydroxyvitamin D3, western, Southern, and northern analyses failed to disclose any abnormalities in vitamin D3 receptor protein and its gene. Exons 2 and 3 of the vitamin D receptor cDNA, which encode the DNA-binding domain consisting of two zinc fingers, were amplified by PCR and sequenced to identify the specific mutations in the vitamin D receptor gene. In the three patients and one normal control a T-to-C transition was found in the putative initiation codon, while this transition was not observed in another normal control. This finding suggested that an original initiation codon was located at positions 10-12 in the human vitamin D receptor cDNA sequence reported previously. In contrast, a unique G-to-A transition at position 140 in exon 3, resulting in substitution of arginine by glutamine at residue 47, was revealed only in these three patients. The arginine at 47 is located between two zinc fingers and is conserved within all steroid hormone receptors. Therefore, it is highly conceivable that this amino acid substitution is responsible for the defect of the vitamin D receptor in the patients. Single-strand conformation polymorphism analysis of amplified DNA confirmed that all patients were homozygous and that parents from one family were heterozygous carriers for this mutation.

Amino Acid Sequence↗
PubMed1991

Concentration of Mn-superoxide dismutase in serum in acute myocardial infarction.

Serum concentrations of manganese-containing superoxide dismutase (Mn-SOD; EC 1.15.1.1), a mitochondrial enzyme present in high concentrations in the heart, were measured successively by enzyme immunoassay in 18 patients with acute myocardial infarction (AMI) and in eight with angina pectoris. Results were compared with creatine kinase (EC 2.7.3.2) isoenzyme MB (CK-MB) concentrations in the same specimens. The mean (and SD) serum Mn-SOD concentration in 120 healthy adults was 77.5 (18) micrograms/L. Mn-SOD concentrations exceeding 150 micrograms/L (greater than mean + 4 SD) were considered above-normal. In patients with AMI, the Mn-SOD concentration was 80 (16.8) micrograms/L on admission and increased gradually after the first hospital day. The peak, 260 (109) microgram/L, occurred on the fourth hospital day, at which time the Mn-SOD concentrations in all AMI patients were above normal. Thereafter the Mn-SOD concentration decreased slowly, but still was above normal in 14 of 18 patients on the seventh hospital day. On the other hand, in patients with angina pectoris, the Mn-SOD concentration was 78 (11) micrograms/L on admission and did not increase significantly [peak value 97.5 (42) micrograms/L on the fourth hospital day]. The serum concentration of Mn-SOD is a potentially useful marker for estimating cardiac mitochondrial damage and for diagnosing AMI, especially in the late phase.

Adult↗
PubMed1990

Expression of human vitamin D receptor in Saccharomyces cerevisiae. Purification, properties, and generation of polyclonal antibodies.

We have cloned a cDNA encoding the human vitamin D receptor (VDR) into a high copy yeast plasmid controlled transcriptionally by the copper-inducible metallothionein (CUP-1) promoter to produce YEpV1. Introduction of this plasmid in the protease deficient Saccharomyces cerevisiae strain BJ 3505 and subsequent growth in the presence of copper and 1,25-dihydroxyvitamin D3 leads to the synthesis of intact VDR comprising over 0.5% of total soluble protein. The VDR was purified to near homogeneity from similarly induced yeast cultures by ammonium sulfate precipitation, and sequential DNA-cellulose and DEAE-Sephadex chromatography, and then characterized for physical and functional properties. The purified VDR associated with a specific synthetic DNA sequence comprising the vitamin D response element as assayed through bandshift analysis. Binding, however, required the presence of a mammalian cell protein factor that also enhances vitamin D response element interaction by mammalian cell-derived VDR. Polyclonal antibodies raised in rabbits against the purified VDR further retarded the receptor/nuclear factor/DNA complex in these analyses. These studies, together with our previous experiments that demonstrate reconstitution of a vitamin D-dependent transcription system in yeast, show that the VDR can be produced and purified from yeast in a functional form.

Calcitriol↗
PubMed1990

[Analysis of factors associated with the occurrence of low birth weight infants].

The relationship between low birth weight infants (LBW) and 3 perinatal factors; pre-pregnant maternal Body Mass Index (BMI: Quetelet's index), maternal height and parity was investigated by the log-linear analysis, using the birth records of an obstetric facility at Naha city. In this facility there were 4,894 deliveries from Jan. 1978 to Dec. 1987. Of the 4,894 infants, 4,142 were live singletons with available data for the analysis. The odds ratio of each risk factor was calculated by the log-linear model. Women with lower pre-pregnant BMI (less than 20) had an increased LBW risk by 1.80 (95% CI: 1.32-2.43) compared to women with higher pre-pregnant BMI (20 less than). Lower maternal height (150 cm greater than) was associated with significant LBW risk (1.47; 95% CI: 1.03-2.12). Primiparae had higher LBW risk than multiparae (1.68; 95% CI: 1.25-2.28). In this analysis we evaluated the interaction effects on LBW occurrence of the three factors and found no interaction effects among them.

Body Height↗
PubMed1990

An immunomodulating protein, Ling Zhi-8 (LZ-8) prevents insulitis in non-obese diabetic mice.

Ling Zhi-8 (LZ-8), a novel and recently discovered immunomodulatory protein having in vivo immuno-suppressive activity, was tested for in vivo effect against Type 1 (insulin-dependent) diabetes mellitus in the nonobese diabetic mouse, the disease having immunologically mediated aetiology in this animal. LZ-8 had mitogenic activity in vitro towards spleen cells of the non-obese diabetic mice as previously shown towards those of DBA/2 mice. Intraperitoneal administration of LZ-8 twice weekly into the mice (10.3-12.6 mg/kg body weight) from 4 weeks of age prevented insulitis and an almost normal number of insulin producing cells were observed. Extreme insulitis and reduction of the number of insulin producing cells were observed in the pancreata of the untreated non-obese diabetic mouse. No cumulative incidence of diabetes mellitus was observed in the LZ-8 treated group, while cumulative incidences of 70% and 60% were observed in an untreated group followed up to 42 weeks of age when the incidence of diabetes was defined as a plasma glucose level of greater than 11 mmol/l and as a urine glucose level of greater than 2+, respectively. T cell subset population analysis was performed to further investigate the action of LZ-8 on the non-obese diabetic mouse which revealed that LZ-8 treatment increased in L3T4'/Lyt-2+ ratio.

Adjuvants, Immunologic↗
PubMed1990

Vitamin D receptor interaction with specific DNA requires a nuclear protein and 1,25-dihydroxyvitamin D3.

The regulation of osteocalcin gene expression by 1,25-dihydroxyvitamin D3 is mediated by the vitamin D receptor and a cis-acting DNA response element that has been identified within the 5' region of the osteocalcin promoter. In this report, we show that vitamin D receptors derived from nuclear extracts of mammalian cells bind directly to this cis-acting element in vitro and do so in a manner requiring hormone. Vitamin D receptors derived from reticulocyte lysate translations in vitro or from extracts of a Saccharomyces cerevisiae strain that expresses the recombinant protein also bind the osteocalcin responsive element, but only when nuclear extracts of mammalian cells are provided. The vitamin-D-receptor-DNA-binding accessory factor is isolated by salt extraction, labile to temperature, and sensitive to tryptic digestion. These studies suggest that the high-affinity interaction of the vitamin D receptor with the osteocalcin vitamin D response element in vitro requires both 1,25-dihydroxyvitamin D3 and an accessory protein derived from the mammalian cell nucleus.

Animals↗
PubMed1990

Role of spectral cues in median plane localization.

The role of spectral cues in the sound source to ear transfer function in median plane sound localization is investigated in this paper. At first, transfer functions were measured and analyzed. Then, these transfer functions were used in experiments where sounds from a source on the median plane were simulated and presented to subjects through headphones. In these simulation experiments, the transfer functions were smoothed by ARMA models with different degrees of simplification to investigate the role of microscopic and macroscopic patterns in the transfer functions for median plane localization. The results of the study are summarized as follows: (1) For front-rear judgment, information derived from microscopic peaks and dips in the low-frequency region (below 2 kHz) and the macroscopic patterns in the high-frequency region seems to be utilized; (2) for judgment of elevation angle, major cues exist in the high-frequency region above 5 kHz. The information in macroscopic patterns is utilized instead of that in small peaks and dips.

Adult↗
PubMed1990

Episodic fluctuation in serum intact parathyroid hormone concentration in men.

To evaluate the temporal features of physiological fluctuation in serum PTH concentration, we sampled peripheral blood at 4-min intervals for 24 h from five normal men (32.8 yr; range, 26-40 yr) and measured serum PTH levels using a two-site immunoradiometric assay with the exquisite sensitivity and specificity for human PTH-(1-84) (intact PTH). The resultant 24-h time series of serum intact PTH levels were assessed by contemporary techniques in chronophysiology for rhythmic and episodic peak detection. Cosinor analysis disclosed a significant circadian rhythm in serum intact PTH concentrations in all five men, with the mean circadian amplitude and acrophase of 7.2 +/- 4.4 ng/L and 2305 +/- 401 h, respectively (mean +/- SD; n = 5). No apparent fixed ultradian periodicity was found by autocorrelation and spectral analyses. Evaluation of episodic intact PTH pulsatility by Cluster analysis revealed 23.0 +/- 4.4 discrete PTH pulses/24 h (P less than 0.01 vs. signal-free noise), which occurred at an interpulse interval of 61.6 +/- 11.1 min. The average duration of a serum intact PTH peak was 42.8 +/- 7.3 min, and its mean incremental amplitude was 12.6 +/- 1.3 ng/L, which corresponded to a 31.8 +/- 5.2% increase above the preceding nadir. Discrete PTH peaks were separated by nonpulsatile valleys which lasted for 17.9 +/- 4.4 min. Cross-correlation between the time series of serum intact PTH and whole blood ionized calcium (Ca2+) was at its maximum (-0.5) at concurrent time points in three subjects, while significant positive correlation between serum intact PTH and simultaneous serum inorganic phosphorus concentrations was observed in four of five subjects. There was no apparent correlation between the levels of serum intact PTH and serum magnesium. Our data show that serum levels of intact PTH, the only biologically active form of PTH in the blood, is characterized by a significant circadian periodicity, spontaneous episodic pulsatility with distinct peak properties, and a significant temporal coupling with Ca2+ and inorganic phosphorus concentrations. We conclude that PTH secretion, as judged by the temporal pattern of serum intact PTH levels, is pulsatile in normal men.

Adult↗
PubMed1990

A unique point mutation in the human vitamin D receptor chromosomal gene confers hereditary resistance to 1,25-dihydroxyvitamin D3.

The syndrome of hereditary resistance to 1,25-dihydroxyvitamin D3 is due to defective function of the vitamin D receptor (VDR). The recent cloning and nucleotide sequence determination of the human VDR chromosomal gene have enabled a direct evaluation of the genetic basis for this disease in affected patients. In this report we employed polymerase chain reaction techniques to amplify the gene exons that encode the DNA-binding domain of the VDR from two 1,25-dihydroxyvitamin D3-resistant patients whose receptors displayed defective binding to nonspecific DNA. Although their families were apparently unrelated, each patient displayed an identical homozygous point mutation within the third exon, a mutation that causes substitution of a glutamine for an arginine residue highly conserved within the entire steroid receptor superfamily. We introduced this base change into the normal VDR cDNA via site-directed mutagenesis, transfected an expression vector containing this cDNA into cells, and examined the functional properties of the resultant VDR expression product. The produced mutant receptor bound 1,25-dihydroxyvitamin D3 with normal affinity, but displayed weak affinity for the nuclear fraction and for heterologous DNA. More importantly, the protein was inactive in promoting transcription in a cotransfection assay employing a chloramphenicol acetyltransferase gene reporter fused down-stream of the VDR-inducible osteocalcin gene promoter-enhancer. These results provide the genetic and functional basis for the phenotype of rickets in this inherited disease.

Amino Acid Sequence↗
PubMed1990

[Secular changes of the mean birth weight and the mean gestational day at an obstetric clinic in Naha].

In our previous study we reported that the secular change of the mean birth weight (MBW) of Okinawa was different from that of Japan as a whole, that is, the MBW of Okinawa was lower, but the annual increase rate of the MBW of Okinawa was larger than that of Japan as a whole. Through analyses using birth records of several obstetric facilities in Naha, we concluded that this phenomenon must be due to the remarkable improvement of the socioeconomical environment of Okinawa. In this report we analyzed secular changes of mean birth weight (MBW) and mean gestational day (MGD) of 15,847 singleton babies born at an obstetric clinic in the city of Naha for the 33 years from 1955 to 1987. To avoid fluctuations of annual changes in MBW and MGD caused by a small number of babies born in a single year, we also used the moving average of three years. In analyzing birth weight we stratified birth weight by sex, parity and the number of gestational weeks. It is considered that birth weight stratified by the number of gestational weeks reflects the intrauterine growth rate of infants. According to our results, both the MBW of infants with 40 gestational weeks, which reflects the intrauterine growth rate, and the MGD increased during the period from the 1950s to the early 1970s in this clinic. On the basis of these results we concluded that the increase of birth weight in this clinic until the early 1970s was due to increases in both the intrauterine growth rate and the gestational period. Our results also show that the mean height of mothers who delivered at this clinic also increased, which might reflect the development of the socioeconomical environment during their childhood. During the period when MBW increased, the economic growth rate of Okinawa was higher than that of other prefectures. From these results we concluded that the MBW can be used as a community health indicator reflecting the total health condition in a given community.

Birth Weight↗