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Biomedical subjects

T Shioiri

Publications and source records attributed to T Shioiri.

At least 73 records · Page 4Linked to original sources
PubMed1993

Brain lithium concentrations measured with lithium-7 magnetic resonance spectroscopy in patients with affective disorders: relationship to erythrocyte and serum concentrations.

Brain lithium concentrations were measured in eight patients with affective disorders using lithium-7 magnetic resonance spectroscopy (MRS). Brain lithium concentrations correlated better with serum concentrations (n = 23, r = 0.66, p < 0.001) than with erythrocyte concentrations (r = 0.44, p < 0.05). Because of previous data in animal experiments these results were unexpected, but the differences in cation transport mechanisms between neurons and erythrocytes may account for the results.

Adult↗
PubMed1993

Alterations in brain phosphorous metabolism in bipolar disorder detected by in vivo 31P and 7Li magnetic resonance spectroscopy.

Phosphorus-31 magnetic resonance spectroscopy (MRS), able to detect membrane metabolism and intracellular pH as well as energy metabolism in vivo, was applied to 17 bipolar patients in the manic state and the euthymic state. In nine of these patients, brain lithium concentration was simultaneously determined by means of lithium-7 MRS in order to clarify the effect of treatment with lithium on brain phosphorous metabolism. Both phosphomonoester (PME) peak area and intracellular pH were found to be higher in the manic state than in the euthymic state. These values in the euthymic state were lower than those in normal controls whose ages and sexes were matched with the patients. However, PME and intracellular pH did not correlate to brain lithium concentration. These findings coincide with a hypothesis that patients with bipolar disorder may have membrane abnormality in their euthymic state and state-dependent alteration of catecholaminergic activity may be a secondary phenomenon.

Adult↗
PubMed1993

Changes in the frequency distribution pattern of body weight in patients with major depression.

To compare the frequency distribution of body weight of the depressed patients with that of a standard group and to evaluate the change in distribution during treatment, body weight was measured in 106 depressed inpatients with major depressive disorder as defined by DSM-III criteria both on admission and on discharge. The body weight distribution in the depressed patients skewed towards a high frequency of lower weights on admission but shifted to the normal pattern on discharge. In women, this tendency was more obvious and was statistically significant. The body weight distribution in the depressed patients with melancholia maintained high frequencies of lower body weight on discharge, while that in those without melancholia did not, suggesting that there could be a difference in the pattern of body weight distributions between those with endogenous and nonendogenous depression. Three tricyclic antidepressants examined (imipramine, clomipramine and desipramine) did not seem to have the side effect of pathological weight gain in the frequency distribution pattern.

Adult↗
PubMed1993

Molecular conformation of patellamide A, a cytotoxic cyclic peptide from the ascidian Lissoclinum patella, by X-ray crystal analysis.

As part of a series of investigations into the conformational stability of a C2-symmetric or related cyclic peptide isolated from the ascidian Lissoclinum patella, the molecular conformation of patellamide A, the chemical structure of which deviates slightly for C2-symmetry, was determined by X-ray crystal analysis. Patellamide A took on a saddle-shaped rectangular form and wrapped around the water and methanol solvents. This conformation which is very similar to that of C2-symmetric ascidiacyclamide would be proposed as a possible candidate for biologically "active" conformation.

Animals↗
PubMed1992

Molecular conformation of ascidiacyclamide, a cytotoxic cyclic peptide from Ascidian: X-ray analyses of its free form and solvate crystals.

In order to investigate the conformational variation of ascidiacyclamide, a cytotoxic cyclic peptide from marine tunicate Ascidian, single crystals were prepared from ethanol and aqueous ethanol solutions as its free form (crystal I) and H2O/0.5 C2H5OH solvate (crystal II), respectively, and were determined by the x-ray diffraction method. Crystal I showed a pseudo C2-symmetric saddle-shaped rectangular conformation. Similar conformations were also observed in crystal II, where there were two crystallographically independent C2-symmetric molecules (named Mol-A and -B) per asymmetric unit. Mol-A and -B included H2O and H2O/C2H5OH solvents within their ring structures, respectively. These water and ethanol molecules were located on the crystallographic dyad axes, and were stabilized by the van der Waals contacts (including hydrogen bonds) with the polar-ring N atoms and nonpolar D-Val side-chain atoms. The conformational characteristics of ascidiacyclamide and its fluctuation/variation were discussed based on the present and previously reported x-ray results.

Animals↗
PubMed1992

Brain phosphorous metabolism in depressive disorders detected by phosphorus-31 magnetic resonance spectroscopy.

Brain phosphorus metabolism was measured in 22 patients with depressive disorders. Ten of them had DSM-III-R bipolar disorder, and 12 had major depression. In bipolar patients, phosphomonoester (PME) and intracellular pH were significantly increased in the depressive state than in the euthymic state, while those values in the euthymic state were significantly low as compared to age-matched normal controls. Phosphocreatine (PCr) was significantly decreased in severely depressed patients compared to mild depressives. These findings suggest that high energy phosphate metabolism, intracellular pH and membrane phospholipid metabolism are altered in depressive disorders.

Adenosine Triphosphate↗
PubMed1992

Biosynthesis of griseolic acids: incorporation of 13C-labeled compounds into griseolic acid A.

Biosynthesis of griseolic acids, competitive inhibitors of cyclic nucleotide phosphodiesterase, was investigated with the culture of a producing strain of Streptomyces griseoaurantiacus. 13C-Labeled and 15N-labeled compounds were added into the culture, and 13C-enriched and 15N-enriched griseolic acid A was isolated from the culture medium and analyzed by 13C NMR and 15N NMR spectroscopy. The compounds added to growth medium were [2-13C]acetate, [1,2-13C]acetate, [1,4-13C]succinate, [1-13C]glucose, [6-13C]glucose, [2-13C]ribose, and [1-13C, 15N]glycine. The results suggest that adenosine, which is formed from amino acids and sugars contributes the adenine and ribose moieties to griseolic acid A. The data also suggest that a dicarboxylic acid from the Krebs tricarboxylic acid cycle contributes to the dicarboxylic part of the compound.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1991

Motor activity correlates negatively with free-running period, while positively with serotonin contents in SCN in free-running rats.

Free-running period of blinded rats kept in a cage with a running wheel varied markedly, while it varied little in rats kept in a cage without a running wheel. The mean free-running period of the former group is significantly shorter than that of the latter. In the former, the free-running period correlated negatively with motor activity, indicating that activity affects the free-running period. In both groups, essentially similar diurnal patterns of biogenic amines and their metabolites were observed in various discrete areas in the brain examined. However, there was a significant difference between the two groups in several areas. In the SCN, 5-HT content correlated positively with motor activity, consequently correlated negatively to the free-running period at 3 out of 4 sampling times over 24 h but no such correlation was observed in other monoamines and their metabolites examined. These facts suggest that 5-HT may be associated with modification of the free-running period.

Animals↗
PubMed1991

Measurement of brain phosphoinositide metabolism in bipolar patients using in vivo 31P-MRS.

In vivo phosphorus-31 magnetic resonance spectroscopy (31P-MRS) was used to measure phosphorus metabolism in the brains of manic patients treated with lithium carbonate. The phosphomonoester (PME) peak was elevated in the manic state in patients with DSM-IIIR bipolar disorder compared to the euthymic state and to drug-free normal controls. Elevation of the PME peak may be caused by lithium-induced accumulation of inositol 1-phosphate in the brain.

Adult↗
PubMed1990

Neutrophil chemotactic activity of N-terminal peptides from the calpain small subunit.

On the basis of previous findings that N-acetyl nonapeptide from the human calpain I large subunit has chemotactic activity for neutrophils, a series of peptides with the N-terminal sequence of the calpain small subunit were synthesized and their chemotactic activity was examined. Potent activity was found in N-acetyl tetra, hepta, octa, nona and a larger peptide of 13 residues, although N-acetyl tripeptide showed only weak activity and N-acetyl penta and hexa peptides showed almost no activity. Since the small subunit is identical in calpains I and II, the results indicate that both calpains could be precursor proteins of chemotactic factors for neutrophils.

Amino Acid Sequence↗
PubMed1990

[The relationship between free-running period and monoamines in the SCN].

Free-running period of blinded rats that had kept in a cage with a running wheel varied markedly between 23.4-24.7 h. The free-running period correlated negatively with motor activity (r = -0.61, P less than 0.005). In the SCN, 5-HT concentration correlated positively with motor activity (r = 0.70, P less than 0.005), consequently correlated negatively to the free-running period (r = -0.79, P less than 0.005). Similarly, 5-HIAA content showed weakly negative correlation to the free-running period (r = -0.45, P less than 0.05) but such correlation was never observed in other monoamines and their metabolites examined (NE, DA, DOPAC and HVA). Further, no correlation was seen between free-running period and contents of amines and their metabolites, including 5-HT and 5-HIAA, in the areas tested other than SCN. These facts suggest that motor activity affects the activity of serotonergic system in SCN, resulting in the change in the free-running period.

Animals↗