1,720,958 research outputs found
Alterations in thyroid function among the different polycystic ovary syndrome phenotypes
No full textThe study evaluates the prevalence of subclinical thyroid dysfunction in infertile PCOS patients, according to the different PCOS phenotypes and to examine whether insulin sensitizers in insulin resistant (IR) PCOS patients may improve thyroid function. The study population consisted of all PCOS patients, attending the infertility and IVF unit of Department of Pediatrics, Obstetrics and Reproductive Medicine of University of Siena, Italy, and compared them to regularly cycling, healthy, infertile controls. Upon admission, blood was drawn from all patients during the early follicular phase, for complete hormonal and metabolic profiles. In IR-PCOS patients treated with insulin sensitizers, blood was drawn again after 6 months. PCOS patients had a significantly higher prevalence of subclinical thyroid dysfunction compared to infertile controls. While no significant association was detected between TSH value and the presence of hyperandrogenism, overweight and obese PCOS patients, as well as IR PCOS patients showed significantly higher prevalence of subclinical thyroid dysfunction. Moreover, among IR PCOS patients, 6 months treatment with insulin sensitizers significantly reduces TSH levels. Infertile PCOS patients have a high prevalence of subclinical thyroid dysfunction, which may be successfully treated in IR PCOS patients by insulin sensitizer
Effect of a new oral contraceptive with estradiol valerate/dienogest on carbohydrate metabolism
No full textBackground: Insulin resistance may be induced by both the estrogen and progestin component in hormonal contraception. When estrogen dose is reduced from 50 to 20 mcg, the extent of hyperinsulinemia decreases. Recently, the oral combination contraceptive (COC) containing estradiol valerate (E2V) in combination with dienogest (DNG) was developed in a new estrogen step-down, progesterone step-up dosing strategy (Qlaira, Bayer Healthcare Pharmaceuticals). This study was conducted to evaluate of the effect of a 3-month treatment with E2V/DNG on carbohydrate metabolism in women with polycystic ovarian syndrome (PCOS) and insulin resistance.
Study Design: Study consisted of subjects attending the gynecological clinic of Siena or Pisa, with PCOS and insulin resistance, and without contraindications for the use of COCs. PCOS females (n=20) aged 18 to 33 years were treated with a contraceptive formulation containing E2V/DNG for 3 months. Before treatment and during the third month of therapy, body mass index (BMI) measurement and an oral glucose tolerance test (OGTT) were performed.
Results: Median values of insulin after treatment were lower than median values before treatment. In particular, the median value of insulin at To was reduced by 54.6% (p<.001), and the mean difference between time 0 and 30 min was significantly reduced [42.96 (9.99) mU/mL vs 38.00 (15.10) mU/mL; p<.05]. Homeostasis model assessment of insulin resistance levels were significantly decreased following treatment. OGTT after treatment revealed median fasting glucose levels to be stable (p=.895) at T-0. At T-30, T-60, T-120 and T-180 min, glucose median values were moderately reduced in comparison to median values before treatment. No significant difference was observed between median BMI values before [26 (4.8) kg/m(2)] and after treatment [26 (3.7) kg/m(2)].
Conclusions: Median insulin levels at T-0 and the mean difference between time 0 and 30 of insulin following OGTT were significantly reduced than values before treatment with E2V/DNG for 3 months. Median BMI and glucose levels were not significantly modified. Natural estradiol and nonandrogenic progestogen in the Qlaira formulation could be recommended as an oral contraceptive in women with PCOS who are insulin resistant or who are overweigh
Present and future of recombinant gonadotropins in reproductive medicine
No full textPharmacological ovarian stimulation has a major role in reproductive medicine and has been used in anovulatory patients and in the induction of multifollicular development required for the procedures of assisted reproductive techniques (ART). Currently, gonadotropins are the most important tools to proceed with ovarian stimulation for all purposes, including ART and anovulation disorders, like hypogonadotropic hypogonadism and hypothalamic hypophyseal dysfunction. Gonadotropin preparations derived from human urine have been used clinically since the early 1960s and the first urine-derived preparation containing only FSH (urofollitropin) became available in 1983. More recently, the application of recombinant DNA technology has resulted in the development of recombinant FSH produced in mammalian cells. In the last period, LH became available by recombinant DNA technology and is now a new option for protocols of ovarian stimulation. Treatment with gonadotropins has been shown to be effective in males affected by hypogonadotropic hypogonadism. This success has resulted in attempts to utilize FSH therapy in oligozoospermic men, aimed at obtaining a quantitative increase in sperm count. The purpose of this review was to examine the pharmacological aspects and different clinical applications of recombinant gonadotropins (FSH, LH, hCG) in the treatment of female infertility in all its aspects and their use also in the treatment of male infertility. This review will trace these events, from the past through to the present, and conclude with a glance towards the future
Hormonal contraceptives: Pharmacology tailored to women's health
No full textBACKGROUND: In recent years, several new oral contraceptives have become available. In some ways, they represent an evolution in terms of individualization and compliance on the part of women. The new formulations make it increasingly possible to prescribe a specific hormonal contraceptive on an individual basis. METHODS: A systematic literature search of PubMed was performed using the following combination of terms: 'oral contraceptives', 'estroprogestins' and 'combined oral contraceptive'. Only English-language papers published between January 2000 and July 2014 were included in our analysis. The present review analyzes all aspects of the choice of oral contraceptives in the different phases of a woman's life in detail. RESULTS: Regarding the estrogen component, lowering the dose of ethinylestradiol (EE) helped reduce associated side effects. Natural estradiol is now available and represents a valid alternative to EE. And regarding progestins, the dose has changed over time, as well as the endocrine and metabolic characteristics. These are the fruit of much research into improvement of old products (19-nor-progesterone-derived progestins) with androgenic effects and testing of new molecules with improved metabolic neutrality in terms of insulin sensitivity and lipid parameters. New progestins were a genuine turning point because they greatly reduced major side effects, such as water retention, and their anti-androgenic properties made them indicated for all forms of hyperandrogenism associated with acne and mild hirsutism. The associations of estradiol/dienogest and estradiol/nomegestrol acetate are the most suitable contraceptives for women with abundant menstrual bleeding and can increase the number of potential users of hormonal contraception. CONCLUSION: Progress in the provision of new oral contraceptives has improved the risk/benefit ratio, by increasing benefits and reducing risks. The present challenge is to tailor contraceptives to individual needs in terms of efficacy and protection of reproductive health
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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