1,721,384 research outputs found
Cardiolipin increases in chromatophores isolated fromRhodobacter sphaeroides after osmotic stress:structural and functional roles
No full textThe contraceptive pill has been a revolution of the last 40 years. In Italy, however, it is much less widely used than in other countries. Explanations for this phenomenon range from religious implications and customs to misinformation and word-of-mouth communication of negative experiences. The oral contraceptive pill is often used to correct menstrual disorders, leading to poor results and side-effects. Recent advances in oral contraception have led to a substantial reduction in doses and side-effects. Low-dose pills contain minimal doses of progesterones and estrogens and ensure good control of the menstrual cycle. Although reduction of ethinyl estradiol (EE) concentrations has reduced the incidence of negative systemic side effects such as water retention, edema and swollen breasts, the low estrogen dose may be associated with spotting and hypomenorrhea or amenorrhea in the long term, as well as dyspareunia due to reduced vaginal trophism, which may induce women to suspend use of the drug. It is also true that only one type of estrogen is used in the pill, albeit at different doses, whereas the progesterone may differ and in many cases is the cause of common side-effects. The choice of progesterone therefore involves not only its effect on the endometrium in synergy with estrogen, but also possible residual androgenic activity which may have negative metabolic repercussions. Indeed, addition of a progesterone, especially androgen-derived, attenuates the positive metabolic effects of estrogen. Two new monophasic oral contraceptives were recently released. They contain 30 microg (Yasmin) or 20 muicrog (Yasminelle) EE and a new progesterone, drospirenone, derived from spirolactone, which has antiandrogenic and antimineralcorticoid activity similar to endogenous progesterone. Like progesterone, the drospirenone molecule is an aldosterone antagonist and has a natriuretic effect that opposes the sodium retention effect of EE. It may, therefore, help to prevent the water retention, weight gain and arterial hypertension often associated with oral contraceptive use. Recent comparative studies recorded weight loss that stabilized after 6 months of treatment with drospirenone/EE. Overweight women may therefore benefit from the formulation with 20 microg EE, whereas the formulation with at least 30 microg EE should be more appropriate for underweight women. Women with slight to moderate acne, the formulation with 30 microg EE has been found to be as effective as 2 mg cyproterone acetate combined with 35 micrig EE (Diane). Menstrual cycle characteristics, however, remain the main factor determining the choice of formulation. Randomised control studies comparing the new formulation with others containing second or third generation progesterones have found similar efficacy in cycle control and incidence of spotting. From this point of view, it is not advisable to prescribe more than 30 microg EE (Yasmin or Yasminelle) for women with normal menstrual cycles, whereas in cases of hypomenorrhea and/or amenorrhea at least this dose of EE plus drospirenone may be used. Women with hypermenorrhea run the risk of spotting if an inappropriate drug is chosen. A solution is to use 30 microg EE/drospirenone from day 5 of the cycle. To control so-called minor side-effects, the dose of EE must be appropriate. In women with premenstrual tension a dose of at least 30 microg EE associated with drospirenone reduces or even prevents symptoms. On the other hand, in cases of chronic headache or headache as a side-effect of oral contraceptive use, a lower dose of estrogen is beneficial, and doses below 20 microg may be used. Although the progesterone component is not considered to affect headache, good results have been obtained with drospirenone, the antimineralcorticoid effects of which reduce blood pressure and improve symptoms. Formulations with 20 microg EE and drospirenone are particularly indicated in women with pre-existing mastodynia, fibrocystic breast manifestations or who develop mastodynia as a side-effect of oral contraceptive use. Since high plasma concentrations of androgens have been recorded in these women, a progesterone with antiandrogen and antiedema activity can be beneficial. Finally, it is worth recalling that monophasic pills with low estrogen doses, such as the formulations mentioned above, ensure good mood control, reducing the depressive symptoms often associated with oral contraceptive use. In conclusion, formulations containing drospirenone are a valid alternative to conventional oral contraceptives for the personalisation of these drugs
[Uterine fibromas and the hormonal pattern: the therapeutic considerations] Fibromiomi uterini e pattern ormonale: Considerazioni terapeutiche
No full textUterine fibromyomatosis is a widely recognised and well studied pathology that is found in around 30% of over 35-year-old women. It has been extensively demonstrated that the etiology of fibromyomas is hormone dependent and to date the main pathogenetic role in the development of these benign tumours has largely been attributed to estrogens. Uterine fibromyomas have been found to contain a higher level of estrogen and progesterone receptors than in normal uterus. This suggests an etiopathogenetic role also for progesterone, which is confirmed by the higher mitotic index of myomatous tissue cells in luteal phase. Growth factors also seem to be involved in the origin of uterine fibromyomatosis: concentrations of epidermal growth factor (EGF), insulin like growth factor 1 (IGF-I) and platelet derived growth factor (PDGF AB) are present in myomatous tissues together with their receptors. Recent studies have shown that the administration of an anti-progestin compound, like RU 486, causes a reduction in fibromyoma size. The role of progesterone in promoting uterine growth opens new horizons in the treatment of uterine fibromyomatosis. Treatment with GnRH analogs has proved effective in reducing the size of fibromyomas, even if the problem of their regrowth once treatment has been suspended remains unsolved. The administration of 100 mg of danazol for 6 months after treatment using GnRH analogs reduce fibromyoma rebound growth by around 30%
Thyrotropin secretion before and after ovariectomy in premenopausal women
No full textMany studies have shown a physiological reduction in thyroid function with age in animals, and less clearly in humans, with an increase in the incidence of age-dependent clinical and subclinical hypothyroidism. Women are more subject to thyroid dysfunction than men. In postmenopausal women the sudden drop in estrogen levels may affect not only pituitary gonadotropins but also other pituitary hormones directly or indirectly involved in reproductive function. The response of thyrotropin to thyrotropin releasing hormone (TRH) has been shown to decrease with age and basal levels of thyrotropin have been found to be reduced in elderly subjects. In the present study we evaluated the response of thyrotropin to TRH before and after ovariectomy in premenopausal women and during estrogen therapy. The response of thyrotropin to TRH after ovariectomy was significantly less than before. Estrogen replacement therapy restored the thyrotropin response to TRH to pre-ovariectomy levels. This significant decrease in the thyrotropin response to TRH observed in surgical postmenopausal women may be explained by lower endogenous estradiol levels.
PMID: 8147238 [PubMed - indexed for MEDLINE
Is micronutrients supplementation useful in pregnancy? [La supplementazione di micronutrienti è utile in gravidanza?]
No full textUse of micronutrients in pregnancy appears to be useful in prevention of some pregnancy related pathologies if used continuously before and during all nine months of pregnancy. The assumption of specific micronutrients, with vitamins and mineral salt inside, could be use to correct some deficiencies and prevent the onset of specific pregnancy related diseases. An adequate support of micronutrients can ensure physiological fetal growth contributing to the development of various fetal organs. Besides folic acid administered in appropriate doses (>400 mug), that it is able to prevent some fetal diseases, such as the closure of the neural tube, other vitamins such as vitamin A are very effective in ensuring an optimal state of health of the mother and slowing the growth of uterine myomas
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