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T Yasunaga

Publications and source records attributed to T Yasunaga.

At least 55 records · Page 3Linked to original sources
PubMed1998

Use of fluid-attenuated inversion recovery (FLAIR) pulse sequences in perinatal hypoxic-ischaemic encephalopathy.

The purpose of this study was to evaluate the usefulness of fluid-attenuated inversion recovery (FLAIR) techniques in patients with perinatal hypoxic-ischaemic encephalopathy. 13 patients with a history of perinatal hypoxic-ischaemic encephalopathy (age range 1 month to 3.6 years) underwent T1 and T2 weighted spin echo and FLAIR imaging with a 1.5 T superconducting unit. FLAIR images were qualitatively evaluated in comparison with T1 and T2 weighted images by three experienced radiologists. Quantitative analysis (contrast and contrast-to-noise ratio) was also performed. FLAIR images were preferred to T1 and T2 weighted images in the demonstration of periventricular leukomalacia (PVL), cystic PVL and subcortical lesions near the brain surface. On T1 and T2 weighted images, almost all lesions were demonstrated as hypointense or hyperintense areas, respectively. However, FLAIR images could differentiate cystic lesions by their signal intensities. FLAIR images were not diagnostic in two cases with PVL. In conclusion FLAIR sequences provide useful information in patients with perinatal hypoxic-ischaemic encephalopathy.

Child, Preschool↗
PubMed1998

Nutrition related hormonal changes in obese children.

Children with simple obesity (SO) show increased linear growth with normal or high serum insulin-like growth factor-I (IGF-I) levels during prepubertal period, despite low GH secretion. We measured IGF-I, IGFBP-1, GHBP and other factors to clarify the hormonal relation between the nutrition and the linear growth in SO and compared these factors with children with normal short stature (NS). Subjects were 23 SO and 19 NS children, and their height standard deviation (SD) scores were 0.7 +/- 0.2 SD and -3.4 +/- 0.3 SD (mean +/- SEM) (P < 0.01), respectively. Oral glucose tolerance test (OGTT) was performed in all the subjects and GH-releasing factor (GRF) test was also performed in 13 of SO and 17 of NS. The peak levels of GH in the GRF test were significantly lower in SO than in NS (12.8 +/- 1.7 vs. 39.8 +/- 6.9 ng/ml) and showed a significantly positive correlation with sigma IGFBP-1 (r = 0.63, P < 0.01). Serum GHBP level and IGF-I level were significantly higher in SO than in NS on pubertal stage matching. There was a positive correlation between GHBP and sigma insulin during OGTT (r = 0.75, P < 0.01). When the sum of the values during OGTT was expressed as sigma, sigma insulin, sigma C-peptide and sigma glucose were significantly higher in SO than in NS on pubertal stage matching. Basal and sigma IGFBP-1 were significantly lower in SO than in NS, but IGFBP-3 levels showed no significant difference between the two groups either in prepuberty or midpuberty. In conclusion, it can be hypothesized that the overnutrition causes hyperinsulinemia which increases GH receptor and IGF-I secretion despite low GH secretion. Hyperinsulinemia also may increase free IGF-I by lowering IGFBP-1. These two mechanism are supposed to be the nutrition related hormonal changes in SO and can explain the growth of SO. In addition, the increased free IGF-I may contribute the decreased GH secretion due to negative feedback in SO.

Adolescent↗
PubMed1998

[MRSA infection concured and exsited and the examination of a home cases].

MRSA (methicillin-resistant Staphylococcus aureus) infection was admitted to 4 cases out of 171 cases that carried out the home medical treatment and exist to, period until to March, in 1998 with this hospital in April, in 1986. As for age, a sex distinction was a mal whichere from 63 years old to 78 years old. A cause disease that reached to home medical treatment was brain blood vessel obstract 2 cases, spine damage 1 case, pulmonary emphysema 1 case. MRSA disappeared with many times wound treatments and a calorie by intra venous hyper alimentary increase that a bed sore cases. An intestinal case was seen a sepsis and candida, MRSA dermatitis with MRSA dermatitis. Bthing servis of it passes, start vancomycin hydrochloride administration peculiar to transnasal tube with improved. The respiratory case pass under tracheostomy tube control with balloon and the detection of MRSA is not admitting with diabetes control with mouth ingestion. It exists and as for MRSA infection the risk of severe infection concurrence is few with only settlement unlike an in hospital a home medical treatment cases with. If an enfeebled persons inside a home are paid attention rigid control is unnecessary. Most important thing are control of local area and improvement of whole body, and whole body.

Aged↗
PubMed1997

N-[2-[(substituted chroman-8-yl)oxy]ethyl]-4-(4-methoxyphenyl)butylamines: synthesis and wide range of antagonism at the human 5-HT1A receptor.

A series of N-[2-[(substituted chroman-8-yl)oxy]ethyl]-4-(4-methoxyphenyl)butylamines was prepared and examined for their 5-HT1A receptor antagonist activity. The parent compound 3a and seven analogs bearing five kinds of substituents on the chroman ring were prepared from the corresponding 8-hydroxychroman intermediates. Radioligand binding assays proved the compounds 3a-h to have high affinity for the rat hippocampal 5-HT1A receptor with varied selectivity for adrenaline alpha1 and dopamine D2 receptors. Their antagonism was evaluated in a forskolin-stimulated adenylate cyclase assay performed with CHO cells expressing the human 5-HT1A receptor. Among the series, the C6-fluoro analog 3c showed both extremely potent affinity (Ki = 0.22 nM) and antagonism (EC50 = 13 nM) for the 5-HT1A receptor. Correlation analysis using substituent descriptors revealed a linear and negative correlation between molar refractivity of the C6-substituent and the binding affinity expressed in pKi.

Animals↗
PubMed1997

A novel common missense mutation G301C in the N-acetylgalactosamine-6-sulfate sulfatase gene in mucopolysaccharidosis IVA.

Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive lysosomal storage disorder caused by a genetic defect in N-acetylgalactosamine-6-sulfate sulfatase (GALNS). In previous studies, we have found two common mutations in Caucasians and Japanese, respectively. To characterize the mutational spectrum in various ethnic groups, mutations in the GALNS gene in Colombian MPS IVA patients were investigated, and genetic backgrounds were extensively analyzed to identify racial origin, based on mitochondrial DNA (mtDNA) lineages. Three novel missense mutations never identified previously in other populations and found in 16 out of 19 Colombian MPS IVA unrelated alleles account for 84.2% of the alleles in this study. The G301C and S162F mutations account for 68.4% and 10.5% of mutations, respectively, whereas the remaining F69V is limited to a single allele. The skewed prevalence of G301C in only Colombian patients and haplotype analysis by restriction fragment length polymorphisms in the GALNS gene suggest that G301C originated from a common ancestor. Investigation of the genetic background by means of mtDNA lineages indicate that all our patients are probably of native American descent.

Asian People↗
PubMed1997

Discrimination of a novel type of rat brain delta opioid receptors by enkephalin analog containing structurally constrained cyclopropylphenylalanine (inverted delta Phe).

Four different stereoisomers of cyclopropylphenylalanine (inverted delta Phe) were incorporated into [D-Ala2,Leu5]enkephalin at the position 4. These conformationally restricted enkephalin analogs were evaluated for their binding characteristics to mu and delta opioid receptors in rat brain. A striking finding is that the E-(2R,3S)-isomer binds to a novel class of delta receptors and discriminates this receptor from the ordinary delta receptor. This new type of delta receptor suspected to be a receptor which suppresses the thermal analgesia mediated through mu receptor. The Z-(2R,3R)-isomer was very potent with several times more enhanced affinity to delta receptors than to mu receptors, but could not differentiate the delta receptors. The Z-(2S,3S)-isomer was weak, and E-(2S,3R)-isomer was almost inactive.

Animals↗
PubMed1997

A survey of genes expressed in mouse embryonal carcinoma F9 cells: characterization of expressed sequence tags matching no known genes.

We prepared 2,132 expressed sequence tags (ESTs) from undifferentiated mouse embryonal carcinoma F9 cells and found that 1,416 match known gene and/or protein sequences [Nishiguchi et al. (1996) J. Biochem. 119, 749-767]. To obtain information on the functions of the remaining 716 unidentified ESTs and to develop a system for characterizing ESTs matching no known genes, we analyzed their sequences by (i) repeated database searches, using the BLASTN, BLASTX, TBLASTX, and FASTA programs, (ii) using computer programs developed or modified for this work, such as the WFASTA, ORFTRNS, and MFASTA programs, together with the DBPROSITE and GRAIL programs, and (iii) examining the expression patterns of the corresponding mRNAs in F9 cells and several organs of adult mice, using the digoxigenin-labeled dot-blot method. We found that 216 of the 716 ESTs match known gene and/or protein sequences, and 307 show significant similarities to these sequences, with a Poisson p-value < 0.01. The strategy and usefulness of such analysis for characterizing unidentified ESTs are discussed.

Animals↗
PubMed1997

Adenoma malignum: MR imaging and pathologic study.

PURPOSE: To evaluate the clinical, pathologic, and magnetic resonance (MR) imaging findings in adenoma malignum, a rare variant of uterine cervical adenocarcinoma. MATERIALS AND METHODS: Medical records of all patients (n = 7) with adenoma malignum of the uterine cervix diagnosed pathologically between 1988 and 1996 were retrospectively reviewed. Unenhanced T1-weighted and T2-weighted images and gadolinium-enhanced T1-weighted MR images were evaluated, and findings were correlated with gross pathologic and microscopic features. RESULTS: In five of seven patients, enlargement of the cervix was seen. All lesions were detected as multiple cystic lesions that extended from the endocervical gland to the deep stroma of the cervix. They appeared isointense (n = 5) or slightly hyperintense (n = 2) relative to the uterus on T1-weighted images and markedly hyperintense relative to the uterus on T2-weighted images. Solid portions of variable size were seen between cystic lesions, and both the multiple cystic component and the solid portion were most apparent on the gadolinium-enhanced T1-weighted images. Microscopic parametrial invasion was seen in two patients but was not detected at MR imaging. CONCLUSION: Adenoma malignum was depicted on MR images as a multicystic mass with solid portions located in the deep cervical stroma. Gadolinium enhancement helped identify the solid portion of the tumor.

Adenocarcinoma↗
PubMed1997

Comparative concentrations of growth hormone-binding protein in maternal circulation, fetal circulation, and amniotic fluid.

Fetal growth is thought to be independent of the concentration of GH, although circulating levels of GH are high in the human fetus. To elucidate the role of GH in fetal development, levels of GH-binding protein (GHBP) were measured in the serum of nonpregnant and pregnant women and neonates as well as in amniotic fluid obtained at various stages of gestation. Total GHBP (the sum of free GHBP and GHBP bound to GH) is measured by a ligand-mediated immunofunctional assay. GHBP concentrations in adult serum were not changed by pregnancy or the stage of gestation. A significant correlation was observed between the concentration of GHBP in the umbilical artery and vein. No correlations were observed between the GHBP concentration and such measures of fetal growth as fetal weight and fetal age. Although the neonatal concentrations of GHBP were significantly lower than those of pregnant women, no correlation was observed between them. GHBP was also present in the amniotic fluid from early to late gestation at concentrations higher than in the cord serum of the neonate. The amniotic GHBP concentration in late gestation was significantly higher than in early gestation. GHBP appears to be derived from GH receptors of fetal organs (most probably fetal liver). The low level of GHBP in fetal serum may be the result of a decrease in GH receptors caused by high levels of circulating GH. GHBP levels in amniotic fluids may be related to the development or maturation of the fetus.

Amniocentesis↗
PubMed1997

Homozygous Q258X mutation in the steroidogenic acute regulatory gene in a Japanese patient with congenital lipoid adrenal hyperplasia.

Congenital lipoid adrenal hyperplasia (CLAH) is an autosomal recessive disorder characterized by impaired synthesis of all adrenal and gonadal steroid hormones. It has recently been reported that mutations in the steroidogenic acute regulatory protein (StAR) gene cause CLAH. We analyzed the nucleotide sequences of exon 7 of the StAR gene in a Japanese CLAH patient with a karyotype of 47,XYY, and her parents. The patient was homozygous for a nonsense mutation Q258X, which changed codon 258 (CAG) encoding Gln to the stop codon TAG, and the her parents were heterozygous for the Q258X mutation. Since the Q258X mutation destroys a MvaI site normally present in the StAR gene sequence, we confirmed the Q258X mutation by means of the restriction endonuclease MvaI digestion of the PCR products. Endocrinological examinations of the parents revealed normal responses of adrenal steroid hormones to exogenous adrenocorticotropin administration, confirming the failure to detect the heterozygous carriers of CLAH by hormonal evaluation.

Adrenal Hyperplasia, Congenital↗
PubMed1997

Single-photon emission CT findings in acute Japanese encephalitis.

PURPOSE: To determine the usefulness of single-photon emission CT (SPECT) in the diagnosis of acute Japanese encephalitis (JE). METHODS: We examined 10 patients (six men and four women; mean age, 69 years) with viral encephalitis. We divided the cases into two groups: the JE group (n = 4) and the non-JE group (n = 6; two with herpes simplex encephalitis and four with encephalitis of unknown origin). All cases were investigated with 99mTc-hexamethylpropyleneamine oxime (HMPAO) SPECT within 15 days after the onset of symptoms. Two patients in the JE group were also examinated by SPECT at a later stage. In all cases MR imaging was performed after the SPECT study. RESULTS: In the acute stage, all patients in the JE group showed a marked increase of HMPAO uptake that matched the hyperintense area observed on MR images in the thalami and putamina bilaterally. Follow-up SPECT studies of two patients with JE revealed a decrease of HMPAO deposition in the areas of high uptake. None of the patients in the non-JE group had an increased accumulation of HMPAO in the thalami or the putamina. CONCLUSIONS: SPECT is helpful in differentiating JE from herpes simplex encephalitis and other types of encephalitis. SPECT may be useful as a diagnostic tool in the early stages of JE.

Acute Disease↗
PubMed1996

Human type II phospholipase A2-induced Mac-1 expression on human neutrophils.

To investigate the effect of type II phospholipase A2 (PLA2-II) on neutrophil function, we assessed the Mac-1 (CD11b/CD18) expression on human neutrophils by flow cytometry after incubation of the cells with human PLA2-II. PLA2-II at a concentration of 10 microg/mL increased the Mac-1 expression by 150% compared with unstimulated cells at 30 min and after. Under these conditions PLA2-II increased the exocytosis from secretory vesicles but not from azurophilic, specific, or gelatinase granules. The results suggest that PLA2-II induces translocation of Mac-1 from the secretory vesicles to the plasma membrane. The Mac-1 induction mediated by PLA2-II was inhibited by an anti-PLA2-II antibody, which was able to inhibit the catalytic activity. However, the Mac-1 induction by PLA2-II was not inhibited by a 5-lipoxygenase, cyclooxygenase inhibitor, or a platelet-activating factor antagonist. Thus, we examined the effects of fatty acids and lysophospholipids on Mac-1 expression. Only arachidonic acid induced Mac-1 expression. These results imply that PLA2-II induces Mac-1 expression on neutrophils via production of arachidonic acid.

Acetophenones↗
PubMed1996

Isolation and characterization of retinoic acid-inducible cDNA clones in F9 cells: a novel cDNA family encodes cell surface proteins sharing partial homology with MHC class I molecules.

Rae-1 cDNA is one of the retinoic acid (RA) inducible cDNA clones in mouse embryonal carcinoma F9 cells. Rae-1 mRNAs were detected in mouse early embryos, but not in various tissues of adult mice. RAE-1 protein apparently consists of 253 amino acids and is likely to be a glycoprotein consisting of a leader sequence, an extracellular domain, a serine, threonine, proline-rich domain, and a transmembrane domain. Interestingly, it has a weak, but significant homology with major histocompatibility complex (MHC) class I molecules and was immunocytochemically identified as a cell surface protein. By determining partial nucleotide sequences of 17 Rae-1 cDNAs isolated from the RA-induced F9 cells, at least three different kinds of Rae-1 cDNAs were identified and were named Rae-1 alpha, Rae-1 beta, and Rae-1 gamma cDNAs, respectively. As the overall nucleotide sequence homology among these three cDNAs was about 98%, they constitute a novel gene family which is likely to be involved in early mammalian embryogenesis.

Amino Acid Sequence↗
PubMed1996

A catalogue of genes in mouse embryonal carcinoma F9 cells identified with expressed sequence tags.

We used expressed sequence tags (ESTs) to identify genes expressed in mouse embryonal carcinoma F9 cells and prepared 2132 ESTs from undifferentiated F9 cDNA libraries: 1026 were prepared after randomly selecting clones from one of the libraries and the remaining 1106 ESTs were prepared after classifying 2896 clones of the libraries into four classes, according to the levels and patterns of expression. Among the former 1026 ESTs, 797 (78%) matched known genes, 61 (6%) matched database sequences of uncharacterized cDNAs, and 168 (16%) represented novel genes. The ESTs matching known genes were catalogued according to putative structural and cellular functions. As many as 53% were related to transcription and translation, and 19% were related to energy metabolism, including transcripts of mitochondrial DNA. These percentages were significantly higher in F9 cells than in the human heart and brain, and a human liver cell line, HepG2. We found that approximately 7% of the ESTs corresponding to low-abundance mRNAs are either related to retinoic acid-regulated genes or mammalian development- and/or differentiation-related genes. Cataloguing of the genes expressed in the F9 cells paves the way for isolating genes involved in early mammalian development.

Adult↗
PubMed1996

Reversible affinity labeling of opioid receptors via disulfide bonding: discriminative labeling of mu and delta subtypes by chemically activated thiol-containing enkephalin analogs.

The 3-nitro-2-pyridinesulfenyl (Npys) group bound to a mercapto group is a highly activated electrophilic reagent, which only reacts with a free mercapto group to form a disulfide bond via the thiol-disulfide exchange reaction. We incorporated the Npys group into enkephalin analogs to affinity label mu and delta opioid receptors. When rat brain membranes were incubated with [D-Ala2,Leu(CH2SNpys)5]enkephalin, and assayed for the inhibition of binding of DAGO and DSLET enkephalin analogs to opioid receptors, the number of receptors decreased sharply, depending upon the concentration of this SNpys-containing enkephalin. It was found that this enkephalin analog occupies mu receptors highly specifically (EC50 = 51 nM) and almost 100 times more selectively than delta receptors. In contrast, [D-Ala2,Leu5]enkephalyl-Cys(Npys)6 attached covalently to delta receptors (EC50 = 34 nM) about 150 times more selectively than to mu receptors. Although N-ethylmaleimide also inhibited the binding of DAGO and DSLET, four to six orders of magnitude higher concentrations were required as compared to SNpys-containing enkephalins. When enkephalin-bound rat membranes were treated with dithiothreitol, the loss of receptors was reversed, depending upon the concentration of and incubation time with dithiothreitol. The recovery was much faster (about 1,000 times) for delta receptors than for mu receptors. The present results indicated that both mu and delta receptors in rat brain consist of a free mercapto group near the enkephalin binding site and that SNpys-containing enkephalins can label these mercapto groups discriminatively. The disulfide bond between [D-Ala2,Leu5]enkephalyl-Cys6 and delta receptors appears to be exposed, while that between [D-Ala2,Leu(CH2-SNpys)5] enkephalin and mu receptors is shielded.

Affinity Labels↗
PubMed1996

Scintigraphic detection of regional disruption of the adrenergic nervous system in sarcoid heart disease.

The presence of defects on resting thallium (201Tl) myocardial scintigraphy has been previously demonstrated in myocardial sarcoidosis. To examine cardiac sympathetic nerve activity in patients with cardiac sarcoidosis, we performed 201Tl and I-123 MIBG (meta-iodobenzylguanidine) myocardial scintigraphy in patients with sarcoidosis. Sixteen patients with sarcoidosis were classified into 2 groups according to the presence or absence of defects on 201Tl scintigraphy. Myocardial images by both 201Tl and I-123 MIBG were then divided into 20 segments and scored using a 6-point scoring system. Defect Score was defined as a the sum of significant scores in each image. The mean Defect Score in I-123 MIBG images was higher in the 201Tl defect group (44.3 +/- 13.3) than in both the normal 201Tl group (25.1 +/- 10.5) and the control group (22.7 +/- 11.4). Moreover, the locations of defects on I-123 MIBG scans were consistent with those on 201Tl scans. This study suggests that cardiac adrenergic function may be impaired in cardiac sarcoidosis, and I-123 MIBG scintigraphy may be more sensitive in detecting cardiac sarcoidosis than 201Tl scintigraphy, although the clinical significance of these findings requires further study.

3-Iodobenzylguanidine↗
PubMed1995

Determination of the protein components of native thin filaments isolated from natural actomyosin: nebulin and alpha-actinin are associated with actin filaments.

A new method was developed for extracting natural actomyosin with full length connectin (titin) and nebulin from rabbit skeletal muscle. To determine the protein components of native thin filaments, thin filaments were isolated from natural actomyosin by sedimentation in a H2O/D2O/sucrose density gradient. Both alpha-actinin and nebulin were cosedimented with actin filaments, while connectin was not. This shows that the native thin filaments contained alpha-actinin and nebulin. This indicates that the native thin filaments were more complicated than synthetic filaments reconstituted from actin, tropomyosin, and troponin. It is known that synthetic filaments are less Ca2+ sensitive than native thin filaments. This difference in Ca2+ sensitivity may be due to the differences in components and/or the different structures of native and synthetic filaments. The newly developed methods described here for extracting natural actomyosin and for isolating native thin filaments are useful for addressing these important problems related to the structure and function of native thin filaments.

Actinin↗