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CHANGES OF NEUROENDOCRINE AXES IN PATIENTS WITH MENSTRUAL MIGRAINE
No full textMenstrual migraine (MM) is a menstrually related disorder (MRD) characterized by several symptoms in common with premenstrual syndrome (PMS). It has been hypothesized that in both MM and PMS hormonal cyclicity could change the balance of neurotransmitters and neuromodulators like monoamine and opioid. In this article we analyze all the data collected by our group on the central opioid tonus and the adrenergic and serotonergic systems in patients affected by menstrual migraine
Platelet serotonin pathway in menstrual migraine
No full textIn order to understand the possible 5-hydroxytryptamine (5HT) anomalies in migraine, particularly in the period before the headache attack, we compared the levels of 5HT, its stable metabolite 5-hydroxyindoleacetic acid (5HIAA) and platelet monoaminoxidase (MAO) activity in patients with menstrual migraine with those of healthy female controls. In every subject, blood samples were drawn during both follicular and late luteal phases of the menstrual cycle. In controls, platelet 5HT levels remained stable, whereas 5HIAA levels and MAO activity were higher in the luteal than in the follicular phase, suggesting an increased catabolism of 5HT which occurs physiologically just before menses. In menstrual migraine 5HIAA levels and MAO activity showed similar changes with higher values in the luteal than in the follicular phase. The luteal phase values were significantly higher than those of controls. Also, and in contrast to controls, 5HT levels decreased in the luteal phase. These data suggest that 5HT availability is reduced in menstrual migraine, possibly due to an increased catabolism and/or to a reduced synthesis, and hence predisposes patients to migraine attacks
Opioid control of the hypothalamus-pituitary-adrenal axis cyclically fails in menstrual migraine.
No full textTo assess the biological correlates of the precipitation of migraine attacks in the perimenstrual period, plasma beta-endorphin (beta-EP) and cortisol responses to naloxone (8 mg iv) and corticotropin releasing hormone (100 micrograms iv) were evaluated in both the follicular phase and the premenstrual period in 7 patients suffering from menstrual migraine and in 7 healthy, asymptomatic control volunteers. In the controls, naloxone evoked a significant release of both beta-EP (F = 5.86, p less than 0.002) and cortisol (F = 4.43, p less than 0.008), independently of the menstrual cycle phase (F = 0.31 and 1.04, for beta-EP and cortisol, respectively). Menstrual migraine patients, on the other hand, showed a significant hormone response only in the follicular phase, not in the premenstrual period. Corticotropin releasing hormone significantly increased beta-EP and cortisol in both the controls and the menstrual migraine patients, independently of the menstrual cycle phase. In both the naloxone and corticotropin releasing hormone testings, the basal beta-EP levels measured in the premenstrual period were lower than those observed in the follicular phase (p less than 0.02). These data demonstrate a cyclical, premenstrual dysfunction of the hypothalamic control exerted by opioids on the hypothalamus-pituitary-adrenal axis. Impairment of this fundamental adaptive mechanism (involved in stress responses and in pain control) could establish a causal relationship between menstrual-related migraine attacks and premenstrual opioid hyposensitivity
Stressful life events and affective disorders inhibit pulsatile LH secretion in hypothalamic amenorrhea.
No full textThe aim of this study was to evaluate relationships between emotional state and hypothalamic activity in patients with hypothalamic secondary amenorrhea. Sixty-seven normal weight patients with hypothalamic amenorrhea were submitted to concomitant psychological and LH pulsatility evaluation. Structured clinical interview for anxiety and depressive disorders (DSM III-R) as well as life events investigations (Paykel test) were performed. LH pulses (blood sampling every 10 min for 4 hr) were analyzed through DETECT program and Instantaneous Secretory Rate were computed. Twenty-one patients reporting life events associated to the onset of amenorrhea had LH pulse frequency (2.28 +/- 1.10 pulses/4 hr) lower than those without life events (3.40 +/- 1.46 p = .007). LH pulses amplitude was lower in patients meeting a DSM III-R (21 cases: 1.22 +/- 0.96 mIU/ml) diagnosis than in those without (1.99 +/- 1.20 p = .04) diagnosis. Plasma estradiol and FSH levels as well as duration of amenorrhea and Body Mass Index were similar among groups. It is concluded that psychogenic factors (namely the presence of life events related to the onset of menstrual disorder) are associated with significant and specific changes of hypothalamic activity which could be involved in determining hypogonadism
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
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