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Biomedical subjects

Y Tahara

Publications and source records attributed to Y Tahara.

116 records · Page 7Linked to original sources
PubMed1977

The structure of the menaquinones with a tetrahydrogenated isoprenoid side-chain.

Menaquinones with a tetrahydrogenated isoprenoid side-chain of Oerskovia turbata and Brevibacterium lipolyticum were cyclized to the chromenyl acetate derivatives, which were then submitted to ozonolysis, followed by reduction with dimethylsulfide. The mass-spectrometric analyses of the ozonolysis products revealed the ion peaks at m/e 464 (M+), 449, 422, 407, 267 and 225. These results suggest that the two saturated double bonds are located continuously in the second and third units of the chain starting from the quinone ring, and the menaquinones are designated as 2-methyl-3-II,III-tetrahydromultiprenyl-1,4-naphthoquinone.

Brevibacterium↗
PubMed1976

An ornithine-containing lipid isolated from Gluconobacter cerinus.

The three ornithine-containing lipids of Gluconobacter cerinus were isolated from each other. One of the three lipids was postulated as Nalpha-3-hydroxypalmitoylornithine, to the fatty acid moiety of which 2-hydroxy fatty acid is linked by an ester linkage. The 2-hydroxy acid was possibly cis-11, 12-methylene-2-hydroxyoctadecanoate. Such an ornithine-containing lipid was found to be distributed in other acetic acid bacteria.

Hydroxy Acids↗
PubMed1976

On the chemical structure of menaquinones with the tetrahydrogenated isoprenoid side chain.

New menaquinones have been isolated from Oerskovia turbata and Brevibacterium lipolyticum in the nocardioform and coryneform groups of bacteria, which have been identified to be a series of menaquinones with a tetrahydrogenated isoprenoid chain, designated as menaquinone-9(H4) and menaquinone-8(H4), respectively, by thin layer chromatography, ultraviolet and infrared spectrophotometry and mass spectrometry. The nuclear magnetic resonance spectra of the quinones have revealed that all the two saturated dolble bonds occur in the internal units of the isoprenoid side chain.

Brevibacterium↗
PubMedDate not supplied

Age-related pattern of body density and body composition in Japanese males and females, 11 and 18 years of age.

The age-related pattern of body density and body composition in Japanese males (n = 266) and females (n = 318), 11.00 to 18.99 years of age was studied. Body density (BD) as well as height, body weight, and seven skinfold thicknesses were measured. Percentage fat (%Fat) was calculated using the age- and sex-specific equation of Lohman. Fat mass (FM), fat-free mass (FFM), and the body mass index (BMI) were calculated. The trend for BD in males was lowest at 11 years (1.0530 g/ml) and increased to 1.0695 g/ml at 14 years, and then decreased slightly at 15 to 17 years. In female, BD decreased from 1.0530 g/ml at 13 years to 1.0424 g/ml at 17 years. Mean %Fat was highest in males at 11 years (15.8%), and lowest at 14 years (10.1%). The highest mean %Fat in females occurred at 16 years (22.8%), and the lowest at age 11 years (15.2%). Overall, only 6.8% of males and 3.1% of females were classified as obese. Between 11 and 18 years, FFM of males differed by 20.7 kg or 67.9%, whereas females showed a difference of only 10.8 kg or 34.7%. Consequently, age effects explained approximately 60% of the male variance of FFM but only 26% in females. Body density of each sex and age group in this study did not differ significantly from previous Japanese studies, and the pooled BD data for 1,457 Japanese including the present study are reported as a reference.

Adolescent↗
PubMedDate not supplied

Age-related pattern of body density and body composition of Japanese men and women 18-59 years of age.

Age-related patterns of body size and composition were studied in a cross-sectional sample of Japanese adults 18-59 years of age. Height, weight, the body mass index (BMI), body density (BD), percentage body fat (%Fat), fat mass (FM), fat-free mass (FFM), and the sum of seven skinfold thicknesses (SF) of 288 men and 552 women were considered. Body density was measured by underwater weighing densitometry. Mean values of height, weight, BMI, BD, %Fat, FM, FFM, and SF of males were 169.0 cm, 65.3 kg, 22.8 kg/m(2), 1.0600 g/ml, 17.0%, 11.4 kg, 53.9 kg, and 95.0 mm, respectively, while corresponding values for females were 157.4 cm, 52.9 kg, 21.4 kg/m(2), 1.0420 g/ml, 24.4%, 13.1 kg, 39.7 kg, and 128.2 mm, respectively. Height, BD, and FFM correlated negatively with age in both sexes, while weight, BMI, %Fat, FM, and SF correlated positively with age. The highest BD and the lowest %Fat were observed in males ages 20 to <25 years (G20) and in females 25 to <30 years (G25). The lowest BD and highest %Fat were observed in G50 in both sexes. Correlations among parameters of body size and composition were stable with age in each sex. Height correlated negatively with BMI and %Fat in females, but not in males. In males, FM started to increase between G20 and G25 and continued to increase until G50, while SF and BMI remained stable during this period. In females, FM accumulation started around 30 years of age and continued until G50 and was accompanied by increases in SF and BMI.

Adolescent↗