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T Yamano

Publications and source records attributed to T Yamano.

At least 145 records · Page 8Linked to original sources
PubMed1988

Golgi study on macular mutant mouse after copper therapy.

This study was undertaken to elucidate the clinical and neuropathological effects of copper administration on the macular mutant mouse. Its hemizygote, which is considered to be a model of Menkes kinky hair disease (MKHD), was injected intraperitoneally four times with 10, 20, 20 and 30 micrograms of cupric chloride on days 4, 6, 8 and 10, respectively. The hemizygote's curly whiskers gradually straightened and the frequent tonic seizures and ataxia disappeared after the injections. The body weight also gradually increased. In the cerebral cortex, the dendritic arborization of the pyramidal neurons in both the normal littermate and the treated hemizygote developed with time and reached the maximum around day 60. In the treated hemizygote, however, the arborization of the dendrites was significantly poor in comparison with that in the normal littermate from day 20 to 90. In the cerebellum of the treated hemizygote, the abnormal Purkinje cells with the few somal sprouts, thick stem dendrite and/or poor arborization, which were seen in the non-treated hemizygote, were improved by day 30, while their focal dendritic swellings remained even on day 60. These results indicate that the copper therapy improves not only the clinical manifestations but also the neuropathological changes, especially in the cerebellum.

Animals↗
PubMed1988

A case of vasculitic cholecystitis associated with Schönlein-Henoch purpura in an adult.

A case of Schönlein-Henoch Purpura (SHP) in a 32 year-old female, showing gastrointestinal manifestations including acute vasculitic cholecystitis was reported. In the course of hospitalization urgent laparotomy was performed because of the severe abdominal pain. The gallbladder was inflamed with a brownish-red edematous wall and subserosal hemorrhage, and was resected. Histological examination of the resected gallbladder specimen revealed leucocytoclastic vasculitis. The patient was treated with prednisolone postoperatively, and symptoms abated over two weeks. Acute cholecystitis with SHP is extremely rare, and as far as the authors know this is the second case of this disorder documented by histological examination. Patients with acute abdomen associated with SHP should be managed with consideration of the complications of acute cholecystitis.

Abdomen, Acute↗
PubMed1988

Aldosterone biosynthesis in mitochondria of isolated zones of adrenal cortex.

An assumption that the aldosterone-synthesizing enzyme exists only in zona glomerulosa cells apparently contradicts our recent findings that a purified bovine adrenocortical cytochrome P-45011 beta catalyzes the aldosterone formation and the enzyme exists in both zones of the adrenal cortex. To gain more insight into the zone specificity of aldosterone production, the aldosterone-synthesizing activity of mitochondria prepared from the isolated zones of adrenal cortex of various animal species was investigated. The intact mitochondria from the bovine or porcine zonae fasciculata-reticularis could not produce aldosterone whereas those from the zona glomerulosa produced it at a significant rate. When the mitochondria from the zonae fasciculata-reticularis were solubilized by the addition of cholate, they produced aldosterone from corticosterone at a rate comparable to that of those from the zona glomerulosa. The presence of specific factor(s) in the zonae fasciculata-reticularis mitochondria inhibiting expression of the aldosterone synthetic activity is discussed. The mitochondria of the rat zonae fasciculata-reticularis could hardly catalyze aldosterone synthesis under the detergent-solubilized conditions, whereas those of the zona glomerulosa could. Immunoblot analysis revealed that the mitochondria of the zonae fasciculata-reticularis contained a protein of Mr 51,000 which was immunocrossreactive with a monoclonal antibody directed against P-45011 beta, whereas those of the zona glomerulosa contained two immunocrossreactive proteins of Mr 51,000 and 49,000. These results suggest that in the case of rat adrenal cortex, a specific aldosterone-synthesizing enzyme exists in the zona glomerulosa.

18-Hydroxycorticosterone↗
PubMed1988

Gluconeogenesis in perfused chicken kidney. Effects of feeding and starvation.

1. Starvation for 48 hr doubled the rate of gluconeogenesis from lactate and pyruvate in perfused chicken kidney, but did not change the rate of production of glucose from malate, succinate, or alpha-ketoglutarate. 2. Amino-oxyacetate and D-malate inhibited the production of glucose from lactate and from pyruvate by 55% in each case. Quinolinate reduced the production of glucose from lactate and from pyruvate by 50% in both fed and starved chickens, but had no effect on the production of glucose from intermediates in the citric acid cycle. 3. Starvation increased the rate of formation of mitochondrial phosphoenolpyruvate from pyruvate, but had no effect on the rate of formation of mitochondrial phosphoenolpyruvate from malate.

Animals↗
PubMed1988

Hepatotoxicity of gardenia yellow color in rats.

Acute toxicity by gardenia yellow color was studied in rats. Oral administration of the colorant at doses of 800 mg/kg up to 5000 mg/kg caused diarrhea and increases in serum alanine aminotransferase and aspartate aminotransferase activities in a dose-dependent manner. After 24 h of oral treatment with 2000 mg/kg of the colorant, liver showed partially hemorrhagic changes and the intestinal tract, especially the duodenum, appeared blue. The toxicity induced by the colorant was stronger by oral administration than by intraperitoneal administration. The content of geniposide, an iridoid compound, was estimated to be 28% of the colorant, and this iridoid accounted for almost all the hepatotoxic activity of the colorant.

Administration, Oral↗
PubMed1988

Biochemical study on the brain of the macular mutant mouse as a model of Menkes' kinky hair disease.

The wet weights, contents of DNA, RNA and protein and 2', 3'-cyclic nucleotide 3'-phosphodiesterase (CNP) activities were examined in the cerebrum, brain stem and cerebellum from macular mutant mouse, as a model animal for Menkes' kinky hair disease (MKHD). The DNA, RNA and protein contents in the cerebellum from macular hemizygous males (Ml/y) were affected to a much greater extent than those in the cerebrum and the brain stem. This suggests that the main affected part of the brain in Ml/y mouse is the cerebellum. CNP activities in the Ml/y mouse showed a significant decrease in every part of the brain after day 10. This finding may coincide with the changes in myelination in human MKHD.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗
PubMed1988

A family with pseudodeficiency of acid alpha-glucosidase.

A unique family is presented which consists of a patient with the juvenile muscular dystrophy form of glycogenosis type II and four healthy individuals, both parents and sisters, with low acid alpha-glucosidase activity. It was almost impossible to distinguish the homozygote from the heterozygous members by lymphocyte assay alone. In cultured skin fibroblasts, acid alpha-glucosidase activity measured with a synthetic substrate was less than 1% of the normal mean value in the patient and about 15% in the parents. The activity toward glycogen was not detectable in the patient and was about 30% of the normal mean value in the parents. These values are also lower than expected in heterozygotes. To explain these results properly, a new mutant allele of acid alpha-glucosidase is proposed. Both parents could be compound heterozygotes for the pseudodeficiency allele and the juvenile form of glycogenosis type II allele.

Adolescent↗
PubMed1988

Isolation, structure, and properties of the beta-carboline formed from 5-hydroxytryptamine by the superoxide anion-generating system.

A yellow substance was isolated by Sephadex LH-20 gel chromatography, silica gel TLC, and reversed-phase HPLC after incubation of 5-hydroxytryptamine (5-HT) with the superoxide anion (O2-)-generating system, i.e., the xanthine-xanthine oxidase system, in the presence of the Fe-EDTA complex and glycine in alkaline medium. The product gave a blue color with Ehrlich's reagent very slowly but no color with xanthydrol and Gibbs' reagent. Its reduced form, however, gave an immediate blue-violet color with all three reagents. No color was developed with ninhydrin, but the reduced form was orange-red. The chemical structure of the yellow substance was identified by 1H-nuclear magnetic resonance and field desorption-mass spectrometry as 4,9-dihydro-3H-pyrido[3,4-b]indol-6-ol (6-hydroxy-3,4-dihydro-beta-carboline, 5-hydroxy-2,3-dihydrotryptoline). The one carbon unit inserted into 5-HT came from glycine, with its 14C-2 being incorporated into C-1 of the yellow substance. The mechanism for the formation of the yellow substance from 5-HT is discussed. This compound inhibited 5-HT uptake into rat brain cortical synaptosomes with an IC50 of 1.5 X 10(-4) M and a Ki value of 1.2 X 10(-5) M.

Animals↗
PubMed1988

X-linked dominant control of F-cells in normal adult life: characterization of the Swiss type as hereditary persistence of fetal hemoglobin regulated dominantly by gene(s) on X chromosome.

Fetal hemoglobin (HbF) levels determined in healthy Japanese adults ranged from 0.3% to 16.0% as F cells and 0.17% to 2.28% as HbF content, which were the same as those obtained in other countries. The frequency distribution of 300 healthy adults with various numbers of F cells consisted statistically of two different groups, low and high F-cell groups. Individuals with greater than or equal to 4.4% of F cells (HbF about 0.7%) were defined as the high F-cell trait, which accounted for 11.3% of males and 20.7% of females. Family studies of 21 probands with this trait and sex-different frequency analyses in the population and probands revealed X-linked dominant inheritance. Two other families of the trait associated with color blindness were described, although no definitive evidence for linkage was obtained between the two. A review of population and family studies reported in the literature indicated that persons with Swiss-type hereditary persistence of fetal hemoglobin (HPFH) are of the same kind as this trait in their incidence and inheritance form, but represent a portion of the trait with higher levels of HbF or F cells. The existence of X chromosome-localized regulatory gene(s) for the developmental switch of human Hb production is discussed.

Adult↗
PubMed1987

Interaction of heme with a synthetic peptide mimicking the putative heme-binding site of histidine-rich glycoprotein.

We synthesized a hexapeptide, Gly-His-His-Pro-His-Gly, previously identified as a tandem motif in the histidine-rich glycoprotein (HRG) which has multiple heme-binding sites. Binding of heme to the peptide was demonstrated by the characteristic difference spectrum showing a close resemblance to that of HRG, implying that the peptide binds heme through biaxial coordination with histidine imidazoles. Furthermore, the EPR spectra of the heme-peptide and heme-HRG complexes were almost completely identical in pattern, showing signals characteristic of the low spin iron. The results suggest that the synthetic peptide simulates the heme-binding properties of HRG and that each tandem motif in HRG serves as a unitary binding site for heme.

Binding Sites↗
PubMed1987

Molecular cloning and sequence analysis of full-length cDNA for mRNA of adrenodoxin oxidoreductase from bovine adrenal cortex.

A full-length cDNA clone (pADR) for adrenodoxin reductase was isolated by means of immunological screening from a bovine adrenal poly(A)+ mRNA library. A cDNA insert of 1,973 base pairs in length encoded the entire amino acid sequence of the adrenodoxin reductase precursor protein, which consists of 492 amino acids including an extrapeptide of 32 amino acids at the NH2-terminus. The cloned cDNA contained the complete 3'-noncoding region of 443 nucleotides including 59 nucleotides of poly(A) and 51 nucleotides in the 5'-noncoding region. The amino acid sequences from the 33rd to 70th, the 117th to 123rd, the 207th to 225th, the 247th to 323rd, the 385th to 426th, the 444th to 461st, and the 487th to 492nd in the predicted structure were identical with those of the purified adrenodoxin reductase and its digested peptides, with only four exceptions.

Adrenal Cortex↗
PubMed1987

Golgi study on brain of macular mutant mouse as a model of Menkes kinky hair disease.

This study was undertaken to elucidate, using the Golgi method, the neuropathological change in the brain of the macular mutant mouse, whose hemizygote (Ml/y) is considered to be a model of Menkes kinky hair disease (MKHD). The hemizygote mice gradually lost weight after 10 days of age and died with emaciation and seizure around day 15. The normal littermate (+/y) was well developed. In the cerebrum, the arborization of pyramidal neurons in the layer V of the Ml/y was the same as that in the +/y on day 10. However, development of arborization in the Ml/y was delayed in comparison with that in the +/y on days 12 and 14. Purkinje cells with several somal sprouts were observed in the cerebellum in both the Ml/y and +/y on day 7. The somal sprouts in the +/y had regressed gradually by day 12, while they were still in the anterior and middle lobes of the Ml/y on day 14. Additionally, the trunks of Ml/y stem dendrites became thicker and a cactus formation was recognized on the branching portion of the dendrites on day 14. Arborization of these abnormal Purkinje cells was distinctly poor compared with that in the +/y. These results suggest that the growth of the neurons is delayed in the Ml/y and simultaneously their cytoskeletal developments are disturbed, especially in the Purkinje cells. There is a close similarity in many respects to the neuropathological change in MKHD.

Animals↗
PubMed1987

Clinico-pathological study on macular mutant mouse.

The macular mutant mouse was clinically and pathologically examined. The hemizygotes began to show white fur color and curly whiskers around postnatal day 3, then seizures and ataxia around day 8, while the normal littermates did not. The hemizygotes also increased weight gradually from birth to day 9, but then showed weight loss and died around day 15 with severe emaciation. These clinical features resembled those in Menkes kinky hair disease. There were no pathological changes in the cerebral cortex in the hemizygotes on day 7. On day 10, two to three clear vacuoles began to appear in a few neurons in the cerebrum. These neurons with vacuoles increased gradually in number and degenerative neurons were also observed by day 14. Ultrastructurally, they corresponded to giant abnormal mitochondria with an electron-lucent matrix and short peripherally located cristae. Other abnormal mitochondria, which were characterized by an electron-dense matrix with tubular or vesicular cristae, were also observed in the cerebral cortical neurons.

Age Factors↗
PubMed1987

Production of 19-hydroxy-11-deoxycorticosterone and 19-oxo-11-deoxycorticosterone from 11-deoxycorticosterone by cytochrome P-450(11)beta.

Incubation of 11-deoxycorticosterone with a cytochrome P-450(11)beta-reconstituted system yielded, in addition to corticosterone and 18-hydroxy-11-deoxycorticosterone, a new steroid product. The retention time of the new product was identical with that of authentic 19-hydroxy-11-deoxycorticosterone on high performance liquid chromatography (HPLC). The turnover number of 19-hydroxy-11-deoxycorticosterone formation was 7.0 mol/min/mol P-450. When a large amount of cytochrome P-450(11)beta was used for the reaction and the products were analyzed by HPLC, the 19-hydroxy-11-deoxycorticosterone peak disappeared from the chromatogram and concomitantly new unidentified peaks appeared. These results suggest that 19-hydroxy-11-deoxycorticosterone was further metabolized to other steroids by cytochrome P-450(11)beta. Therefore, we next incubated 19-hydroxy-11-deoxycorticosterone with cytochrome P-450(11)beta and analyzed the reaction products by HPLC. The above-mentioned unidentified peaks appeared again in the chromatogram. The retention time of one of the peaks coincided with that of authentic 19-oxo-11-deoxycorticosterone. This peak substance was purified by repeated HPLC and subjected to mass spectrometry and 1H NMR analyses. Its field desorption mass spectrum (FD-MS) showed a M+ peak at m/e 344. The 1H NMR spectrum showed the signal of an aldehyde proton instead of those of hydroxymethyl protons at the C-19 position. These results suggest that cytochrome P-450(11)beta can catalyze the 19-hydroxylation of 11-deoxycorticosterone, and the 19-hydroxy-11-deoxycorticosterone produced is further oxidized at the C-19 position to 19-oxo-11-deoxycorticosterone.

Adrenal Cortex↗
PubMed1987

Localization of D-amino acid oxidase in Bergmann glial cells and astrocytes of rat cerebellum.

The localization of D-amino acid oxidase in rat cerebellum was systematically studied in serial fixed sections at the levels of both light and electron microscopy using a coupled peroxidation method based on the intensifying effect of nickel ions. Deposits were only seen in astrocytes and Bergmann glial cells, and not in neuronal components, endothelial cells or ependymal cells. In the molecular layer, heavy deposits were present in the profiles of Bergmann glial processes around the complexes of synapses where the parallel fiber varicosities form synapses with the thorns emerging from the spiny branchlets of Purkinje cell dendrites. In the Purkinje cell layer, the oxidase-containing processes of Bergmann glial cells enveloped basket cell axons, their terminals, the terminals of the recurrent collaterals of Purkinje cell axons and Purkinje cell bodies. In the granular layer, the cerebellar glomeruli were enveloped by the heavily stained processes of astrocytes. Based on this characteristic localization of the oxidase, we discussed the physiological role of the oxidase in connection with the function of glial cells.

Animals↗
PubMed1987

Light and electron microscopic study on cerebellar cortex of macular mutant mouse as a model of Menkes kinky hair disease.

The macular mouse is a mutant mouse, the hemizygotes of which show clinical and biochemical abnormalities similar to those in Menkes kinky hair disease (MKHD) in humans. The cerebellar cortex of this mutant suckling mouse was examined by light and electron microscopy. In hemizygotes, the Purkinje cells showed a delay in the maturation of dendrites and somatic spines. Somal sprouts, abnormal mitochondria, and filamentous cytoplasmic inclusions were observed on these cells on day 13. Axonal swellings, containing abnormal mitochondrias were also seen in the inner granular layer. These findings correspond with those of MKHD in humans and those of the brindled mouse, another model mouse of MKHD.

Animals↗