The bioelectrical-impedance-analysis (BIA) method accurately measures body composition in weight-stable subjects. This study validates the use of BIA to measure change in body composition. Twelve obese females underwent weight loss at a mean rate of 1.16 kg/wk. Body composition was measured by deuterium oxide dilution (D2O), BIA, and skinfold anthropometry (SFA) at baseline and at 5% decrements in weight. Highly significant correlations were obtained between D2O and BIA (r = 0.971) and between D2O and SFA (r = 0.932). Overall, BIA predicted change in fat-free mass with greater accuracy (to 0.4 kg) and precision (+/- 1.28 kg) than did anthropometry (to 0.8 kg and +/- 2.58 kg, respectively). We conclude that BIA is a useful clinical method for measuring change in body composition.
This study was designed to determine whether chronic moderate ethanol ingestion alters the levels of vitamin A of liver and esophageal epithelium and if this is dependent on zinc nutriture. Forty male Sprague-Dawley 4-week-old rats were divided into five groups: zinc-deficient (0.9 ppm), ethanol-fed; zinc-deficient; zinc-adequate (25 ppm); zinc-adequate (25 ppm), ethanol-fed; and zinc-supplemented (50 ppm), ethanol-fed. All rats received liquid Lieber-DeCarli diet containing 4,000 IU per liter of vitamin A for 5 weeks. Zinc-deficient, ethanol-fed rats and zinc-adequate, ethanol-fed rats and zinc-supplemented, ethanol-fed rats received 15.5% of the caloric intake as ethanol while zinc-deficient and zinc-adequate rats received isocaloric amounts of maltose dextrin. All groups were pair-fed to zinc-deficient, ethanol-fed rats. In addition, a group of eight rats designated as weight-restricted controls were fed a diet similar to the one given to zinc-adequate rats but in the amount to obtain a final weight as in the zinc-deficient group. After 35 days, the liver histology was normal in all rats, and no fat accumulation was noted. Hepatic vitamin A concentration was significantly decreased in zinc-adequate, ethanol-fed rats (41 +/- 10 micrograms per gm) and further in zinc-supplemented, ethanol-fed rats (12 +/- 5 micrograms per gm) as compared to controls (137 +/- 49). A highly significant negative correlation between serum zinc and liver vitamin A was found in ethanol-fed animals.(ABSTRACT TRUNCATED AT 250 WORDS)
Guaiacol peroxidase (G-Px) was measured in extracts from five sections along the length of human uterus on different days of the menstrual cycle or after menopause. The lower uterine-endocervical region had a significantly higher G-Px content (expressed as enzyme units per g wet tissue) than the other sections, although in postmenopausal patients the G-Px activity was uniformly low in all sections of the uterine cavity. We observed no significant changes in G-Px levels during the menstrual cycle, except, possibly, a decrease around ovulation, which precluded a positive correlation between plasma estrogen levels and uterine G-Px content; such estrogen dependence of G-Px has been previously shown in the rat. In vitro, G-Px was inhibited by estriol and 17 beta-estradiol, marginally inhibited by estrone, and most notably inhibited by the catecholestrogens tested (2-hydroxy-17 beta-estradiol, 2-hydroxy-estriol, and 2-hydroxy-estrone), which were equipotent inhibitors; LH and FSH, progesterone, or cortisol had no effect on G-Px activity. We hypothesize that catecholestrogens are natural substrates and regulations of G-Px activity in the human uterus.
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