Phyto-oestrogen excretion and rate of bone loss in postmenopausal women

OBJECTIVE: The hypothesis was tested that the rate of postmenopausal bone loss is inversely associated with long-term urinary excretion of phyto-oestrogens, as a marker of habitual dietary intake. DESIGN: Secondary analysis of a 10-year follow-up study (1979 1989) among postmenopausal women in the Netherlands. SUBJECTS: From the original population of 154 women, 32 women were selected with an annual rate of radial bone loss of < or = 0.5% over the first 5 years of the study and 35 women with a rate of > or = 2.5% per year. METHODS: The isoflavonoids genistein, daidzein and equol, and the lignan enterolactone were determined by gas chromatography mass spectrometry in aggregate samples from annually collected urine samples. Cortical bone density of the radius had previously been measured annually by single-photon absorptiometry. RESULTS: Excretion of isoflavonoids did not differ between both groups, although in multivariate analysis equol excretion was weakly positively associated with rate of bone loss in the 5 years after the menopause. Enterolactone excretion was significantly higher in the group with high rate of bone loss. This positive association remained in multivariate linear regression analysis after adjustment for age, years since menopause, body mass index and intake of calcium, vegetable protein and dietary fibre. CONCLUSIONS: Enterolactone excretion is likely to be an indicator of consumption of grains and legumes; it is not clear whether the observed positive association with rate of bone loss is a causal one. Our results do not support a preventive effect of low, unsupplemented dietary intake of phyto-oestrogens on postmenopausal cortical bone loss. However, no conclusions can be drawn about effects of higher doses of phyto-oestrogens.     

Safety of single large oral doses of guanethidine

The cardiovascular effects of single 100-mg doses of guanethidine were assessed in hypertensive patients by measurement of arterial pressure, heart rate, and systolic time intervals. In the 3-hr period following a dose there was no evidence of an inotropic effect. Therefore, large doses of guanethidine as required for the guanethidine loading regimen would seem to be safe even in patients in whom inotropic effects of released catecholamines would be contraindicated.     

A proposed system whereby a (colcemid-induced) S2 phase is responsible for the tetraploidy found in cultured human amniotic fluid cells

The results of this study, using cultured amniotic fluid cells (AFC) and colcemid, together with results of several other investigators who worked with colcemid and DNA synthesis, have led to the proposal of a hypothesis suggesting a mechanism by which tetraploidy may be induced. Data from this study of 24,455 mitotic spreads indicate increased concentrations of colcemid, as well as extended exposure times, results in a higher incidence of tetraploidy in cultured AFC, with no concomitant increase in the unexposed control cells.