1. Nine habitual tea-drinking volunteers were recruited and asked to follow a low-polyphenol and low-caffeine diet for 6 days and to provide daily 24-h urine samples. On day 4 of the experiment strong black tea brewed under standardized conditions was re-introduced to the volunteers' diet. 2. 1H-NMR and HPLC profiling of the urine samples indicated that consumption of black tea (6-10 mugs per day) was associated with a significant (p = 0.00017) increase in hippuric acid excretion relative to control, increasing from 153-512 to 742-1374 mg day(-1). The excretion of substantial amounts of hippuric acid has not previously been associated with black tea consumption. 3. For some volunteers, the quantity of benzoic acid processed exceeded the acceptable daily intake (ADI), but this is not considered to constitute any hazard. 4. A mass-balance analysis indicated that the necessary quantity of benzoic acid could not be obtained from the contents of gallic acid, flavanols, flavonol glycosides and theaflavins in black tea even if 100% transformation was obtained, suggesting that the thearubigins (the major and chemically ill-defined polyphenols of black tea) may be an important source.
The induction of pathologic changes with hormone steroids has been studied in rodents, although comprehensive studies are lacking on the potential reversibility of these lesions. For these purposes, groups of rats were treated with quingestanol acetate and quinestrol, a progestogen-estrogen combination, for 50 weeks and observed for a subsequent 30-week period. Treatment resulted in a significant body weight gain suppression and reduction of food consumption which recovered after withdrawal. Other significant treatment-related effects were hair loss, ataxia due to pituitary enlargement, mammary chain masses with histologic adenocarcinoma, lens opacities, ovarian atrophy with follicular arrest, and uterine atrophic changes with suppurative inflammation throughout 50 weeks. Cessation of treatment did not effect hair loss or lens opacities, while mammary chain masses decreased in size and in incidence; mammary gland tumors showed regressive changes including the disappearance of adenocarcinoma, and the incidence of ataxia diminished together with reduced pituitary weights. Chromophobe cell hyperplasia with decreased eosinophils and acidophils and hemorrhage into the pituitary was observed up to 50 weeks and the tinctorial affinity of basophils and acidophils returned after withdrawal. Ovaries and uteri, which become atrophic and sustained chronic suppurative inflammation in the treatment phase, showed reduction of inflammatory reaction and disappearance of suppuration after withdrawal, and endometrial regeneration occurred with luteal cells seen in the ovaries. These results revealed the regressive characteristics of some of the mammary gland carcinomas as well as steroid-induced endocrine and pathologic lesions other than tegumentary and ocular changes in rats receiving high levels of steroids for prolonged periods of time.
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