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Biomedical subjects

T Tamura

Publications and source records attributed to T Tamura.

At least 1,477 records · Page 82Linked to original sources
PubMed1975

Analysis of methylsterol fractions from twenty vegetable oils.

The 4-monomethylsterol and 4,4-dimethylsterol fractions were separated from the unsaponifiables of 20 vegetable oils by preparative thin layer chromatography, and their compositions were determined by gas liquid chromatography. Tentative identification of the individual components of these fractions was carried out by gas liquid chromatography and combined gas liquid chromatography-mass spectrometry. Among 4-monomethylsterols, obtusifoliol, gramisterol, and citrostadienol occur abundantly in most of the oils. Cycloeucalenol also occurs in some of the oils as a major component of 4-monomethylsterols. Other 4-monomethylsterols tentatively identified are: lophenol, 31-norlanosterol, 31-norcycloartenol, and 31-norlanostenol and/or 4alpha-methylzymostenol. Among 4,4-dimethylsterols, cycloartenol and 24-methylenecycloartanol followed by beta-amyrin and cycloartanol are common to most of the oils. Butyrospermol, alpha-amyrin, lupeol, and cyclobranol together with a 4,4-dimethylsterol, presumably lanostenol, occur in some of the oils. Cyclolaudenol is present in poppy seed oil. Besides these compounds, each of the oils contains some unidentified members of 4-monomethylsterols and 4,4-dimethylsterols. The methylsterol fraction of capsicum seed oil as compared with that of the other oils is characterized by its very high content of lophenol and cycloartanol together with three other members, presumably 31-norlanostenol, 4alpha-methylzymostenol, and lanostenol.

Cholestadienols↗
PubMed1975

Gas chromatographic differentiation of 4-desmethyl-, 4-monomethyl- and 4,4-dimethyl-sterols. Part II : differentiation of sterols based on deltaRAc-values on four stationary phases.

The deltaRAc-values, i.e., ratios of retention data for sterol acetates to those for the corresponding free sterols, were determined for fourteen 4-desmethylsterols, seven 4-monomethylsterols and twenty-two 4,4-dimethylsterols on SE-30, OV-17, QF-1 and HiEFF-8B stationary phases. The QF-1 phase is found sperior to the others in affording the values which are the most effective for differentiation between the three sterol groups. Within the same sterol group, the values for individual sterol members on any of the stationary phases differ to some extent due to minor variations in their skeletal structure. These differences are useful for distinguishing individual members of the same sterol group differing in their skeletal structure, particularly in the position of double bond. The relative deltaRAc-values, i.e., ratios of deltaRAc-values of individual sterols to the deltaRAc-value of a standard sterol, are found almost independent upon the operating conditions of gas liquid chromatography and may be regarded as a characteristic value of sterols on one and the same stationary phase.

Chromatography, Gas↗
PubMed1975

Gas chromatographic differentiation of 4-desmethyl-, 4-monomethyl- and 4,4-dimethyl-sterols. Part III: differentiation of sterols based on deltaROxo-values on four stationary phases.

The deltaROxo-values, i.e., ratios of retention data for 3-oxo derivatives to those for the corresponding free sterols have been determined for fourteen 4-desmethylsterols, six 4-monomethylsterols and twenty-one 4,4-dimethylsterols on SE-30, OV-17, QF-1 and HiEFF-8B stationary phases. The QF-1 phase is found superior to the others in affording the values which are the most effective for differentiation between the three sterol groups. Within the same sterol group, the values for individual sterol members on any of the stationary phases differ to some extent due to minor variations in their skeletal structure. 4-Desmethyl-delta-5-sterols have strikingly large deltaROxo-values and are distinguishable definitely from other members of the 4-desmethylsterol group. The relative deltaROxo-values, i.e., ratios of deltaROxo-values of individual sterols to the deltaROxo-values of beta-sitosterol, also have been calculated from the deltaROxo-values of individual sterols.

Cholestanes↗
PubMed1975

Sterols from a species of Pichia, a n-alkane-utilizing yeast.

The component sterols in the lipid from a yeast, a species of Picia, grown on n-alkanes have been studied. Ergosterol and zymosterol in the 4-desmethylsterol fraction, 4alpha-methylzymosterol in the 4-monomethylsterol fraction and lanosterol in the 4,4-dimethylsterol fraction are present as the major components in the respective fractions. Among the minor components, the presence of 24-methylene-lanostenol, in addition to fecosterol and 4alpha-methylfecosterol, is indicated.

Alkanes↗
PubMed1975

Transmissible enterocolitis in hamsters caused by Tyzzer's organism.

An outbreak of enteric form of Tyzzer's disease occurred in a golden hamster colony, and 60% of diseased animals examined were found to have severe enterocolitis without hepatic lesions. Organisms were detected within mucosal epithelial cells, especially in the lower ileum, cecum and colon showing degenerative and necrotic changes, and in some cases organisms were also detected in the smooth muscle layer. Infiltration of neutrophils and mononuclear cells in the lamina propria and submucosa was observed. Hamsters either having been cage-mates with diseased ones or given perorally cecal contents from affected animals, suffered from severe diarrhea and were shown to have necrotic foci in the liver. By intravenous inoculation with affected hamster liver homogenate into cortisone-treated mice, hepatic lesions characteristic of Tyzzer's disease were produced. Moreover, such infected mouse liver was found to cause severe diarrhea in hamsters when administered perorally.

Animals↗
PubMed1975

[Hepatotropism of Tyzzer bacteria in experimentally infected chick embryos].

Tyzzer's organism from mice propagated more remarkably in hepatocytes than in yolk-sac epithelial cells producing confluent necrosis of the liver after intravenous as well as intravitelline inoculation. Some lesions with bacterial growth were also produced in the heart muscles and kidneys. The organisms from mouse, rat, hamster and kitten were shown to be equally pathogenic for chick embryos.

Animals↗
PubMed1975

[Mouse pancreas involvement in murine hepatitis virus infection].

After intraperitoneal inoculation with mouse hepatitis virus (MHv) into mice, the excretory cells of the pancreas showed a marked vacuolar degeneration concomitantly with hepatitis. MHV-specific antigen was evidenced in the cytoplasm of infected cells. Electron microscopy revealed a number of virions within the matrix, spaces of the endoplasmic reticulum and areas of focal cytoplasmic necrosis. The virus titer of the pancreas was equal or superior to that of the liver at least in early stage of infection.

Animals↗