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Antarctica is one of the world’s most inaccessible regions. This area is also unique in that it has a terrestrial biota dominated by non-vascular plants, of which lichens and mosses are typically the dominant life-forms. A phytochemical study of Antarctic lichen ( Umbilicaria antarctica ) collected from maritime Antarctica has been carried out. The hexane, acetone and butanol extracts have been subjected to a preliminary general bioactivity test using wheat etiolated coleoptiles. A chromatographic study of the acetone extract was performed and seven known compounds were isolated. The general bioactivity of the compounds on etiolated wheat coleoptile has been assessed and joint action studies on mixtures of the compounds were carried out − a methodology that may be the way to a holistic approach in the ecological studies of lichens. The results corroborated the activity exhibited by the original fractions, which in turn support the use of this bioassay to determine joint interactions responsible for the bioactivity shown by U. antarctica. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Early menopause (EM) is included among the risk factors for osteoporosis. Several studies have shown that women with early menopause have lower bone mineral density (BMD) than those with normal expected age of menopause. The aim of our cross-sectional study was to investigate the effects of time of menopause on vertebral bone mass in healthy postmenopausal women and to evaluate if early menopause is a risk factor for lower vertebral BMD. Method: We studied 782 who had never received drugs acting on bone mass. The study population was divided into three groups: women with early, normal (NM), and late (LM) menopause. Our study population was further categorized in 5-year age segments between 45 and >75. Results: The three groups examined did not differ for age, age at menarche, body mass index (BMI), and vertebral BMD, while there were significant differences in age at menopause and years since menopause. Our study showed that women with EM presented significantly lower vertebral BMD than NM and LM in 50–54 age segments. Beyond 55 years, EM, NM, and LM women had no differences in lumbar BMD values. Conclusions: In conclusion, controversial data demonstrated that the absolute amount of bone loss is greater after early menopause than after normal or late menopause, even if a slight effect of early menopause on bone mass cannot be excluded. [Copyright &y& Elsevier]