Melichar B.,Palacky University |
Melichar B.,Charles University |
Plisek J.,Sokolska |
Plisek J.,Charles University |
And 8 more authors.
Journal of Nutritional Science and Vitaminology | Year: 2010
In an earlier study, we have observed an increase of alpha-tocopherol in breast cancer patients treated with third-generation aromatase inhibitors that was related to tamoxifen withdrawal. We report here the results of measurement of alpha-tocopherol in erythrocytes and alpha-tocopherol/cholesterol ratios in patients treated with letrozol. Alpha-tocopherol in lipoprotein fractions and erythrocytes was determined by high-performance liquid chromatography in 124 post-menopausal women with breast cancer treated with letrozol immediately before the start of treatment as well as 2 and 4 mo later. After a transient decrease after 2 mo of letrozol therapy, erythrocyte alpha-tocopherol concentrations returned to pre-treatment levels 4 mo after the start of treatment. Apart from lower cholesterol in patients pre-treated with tamoxifen, no significant differences were observed at baseline between patients previously treated with tamoxifen and patients who had no prior tamoxifen in any of the other parameters investigated, but the transient decrease of erythrocyte alpha-tocopherol was observed only in patients previously treated with tamoxifen. Alpha-tocopherol content of lipoprotein fractions was significantly increased 4 mo after the start of therapy, but this increase was evident mostly in patients not treated earlier with tamoxifen. In conclusion, only minor changes of alpha-tocopherol, including a transient decrease of alpha-tocopherol in erythrocyte membranes, and an increase of alphatocopherol in lipoprotein fractions were observed during the first 4 mo of letrozol therapy.
Ceral J.,Sokolska |
Malirova E.,University of Hradec Kralove |
Kopecka P.,Sokolska |
Pelouch R.,Sokolska |
Acta Endocrinologica | Year: 2011
Context. In patients with suspected primary aldosteronism (PA), the aldosteroneto- renin ratio (ARR) is the most frequently recommended screening test. Further evaluation is based on hormonal changes during volume expansion. Both analyses are critically dependent on an accurate estimation of renin concentration. Direct active renin (DAR) is a novel laboratory technique used for plasma renin assessment. Objective. The objective of this study was to evaluate DAR for use in PA diagnostic work-ups. Subjects and Methods. The study enrolled 69 healthy volunteers. Blood sampling was conducted before and after an increase in oral salt intake. Furthermore, a subset of 32 individuals underwent a saline infusion suppression test. DAR and serum aldosterone were measured in all blood samples. To calculate the ARR, serum aldosterone and DAR were expressed in ng/L. Results. ARR values [median (range); 97.5 percentile] associated with normal and elevated oral salt intake were 8.4 (0.6-37.7); 26.3, and 6.8 (1.1-37.7); 19.6, respectively. DAR and serum aldosterone concentrations [median (range); 97.5 percentile] after saline infusion suppression were 2.9 (2.7-10.7); 7.2 ng/L and 30 (30-72); 54 pmol/L, respectively. Conclusions. The observed values may be useful in excluding a diagnosis of PA.