1,720,985 research outputs found
Congenital Adrenal Hyperplasia, Unresolved Issues and Implications on Clinical Management
No full textThis eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contac
A Randomized Controlled Trial to Assess the Feasibility and Practicability of an Oatmeal Intervention in Individuals with Type 2 Diabetes: A Pilot Study in the Outpatient Sector
Full text linkBackground/Objectives: The aim of this study was to investigate the feasibility and practicability of repeated three-day sequences of a hypocaloric oat-based nutrition intervention (OI) in insulin-treated outpatients with type 2 diabetes and severe insulin resistance. Methods: A randomized, two-armed pilot study was conducted with three months of intervention and three months follow-up with 17 participants with insulin resistance (≥1 IU/kg body weight). Group A (n = 10) performed one sequence of OI; Group B (n = 7) performed two sequences monthly. A sequence was 3 consecutive days of oat consumption with approximately 800 kcal/d. The main objective was to assess feasibility (≥70% completers) and practicability regarding performance aspects. Biomedical parameters such as HbA1 c were observed. To evaluate the state of health, a standardized questionnaire was used (EQ-5 D). Results: OI was feasible (13/17 completer participants (76.5%): 70.0% Group A, 85.7% Group B). Individually perceived practicability was reported as good by 10/16 participants (62.5%). Total insulin dosage decreased from 138 ± 35 IU at baseline to 126 ± 42 IU after OI (p = 0.04) and 127 ± 42 IU after follow-up (p = 0.05). HbA1 c was lower after OI (−0.3 ± 0.1%; p = 0.01) in all participants. Participants in Group B tended to have greater reductions in insulin (Δ−19 IU vs. Δ−4 IU; p = 0.42) and weight loss (Δ−2.8 kg vs. Δ−0.2 kg; p = 0.65) after follow-up. Severe hypoglycemia was not observed. EQ-5 D increase not significantly after follow-up (57.2 ± 24.0% vs. 64.7 ± 21.5%; p = 0.21). Conclusions: The feasibility and practicability of OI in outpatients were demonstrated. OI frequency appears to correlate with insulin reduction and weight loss. Proper insulin dose adaptation during OI is necessary. Presumably, repeated OIs are required for substantial beneficial metabolic effects
Management of the Female With Non-classical Congenital Adrenal Hyperplasia (NCCAH): A Patient-Oriented Approach
Full text linkNon-classical congenital adrenal hyperplasia (NCCAH) is considered to be a common monogenic inherited disease, with an incidence range from 1:500 to 1:100 births worldwide. However, despite the high incidence, there is a low genotype-phenotype correlation, which explains why NCCAH diagnosis is usually delayed or even never carried out, since many patients remain asymptomatic or are misdiagnosed as suffering from other hyperandrogenic disorders. For affected adolescent and adult women, it is crucial to investigate any suspicion of NCCAH and determine a firm and accurate diagnosis. The Synacthen test is a prerequisite in the event of clinical suspicion, and molecular testing will establish the diagnosis. In most cases occurring under 8 years of age, the first symptom is premature pubarche. In some cases, due to advanced bone age and/or severe signs of hyperandrogenism, initiation of hydrocortisone treatment prepubertally may be considered. Our unifying theory of the hyperandrogenic signs system and its regulation by internal (hormones, enzymes, tissue sensitivity) and external (stress, insulin resistance, epigenetic, endocrine disruptors) factors is presented in an attempt to elucidate both the prominent genotype-phenotype heterogeneity of this disease and the resultant wide variation of clinical findings. Treatment should be initiated not only to address the main cause of the patient's visit but additionally to decrease abnormally elevated hormone concentrations. Goals of treatment include restoration of regular menstrual cyclicity, slowing the progression of hirsutism and acne, and improvement of fertility. Hydrocortisone supplementation, though not dexamethasone administration, could, as a general rule, be helpful, however, at minimum doses, and also for a short period of time and, most likely, not lifelong. On the other hand, in cases where severe hirsutism and/or acne are present, prescription of oral contraceptives and/or antiandrogens may be advisable. Furthermore, women with NCCAH commonly experience subfertility, therefore, there will be analysis of the appropriate approach for these patients, including during pregnancy, based mainly on genotype. Besides, we should keep in mind that since the same patient will have changing requirements through the years, the attending physician should undertake a tailor-made approach in order to cover her specific needs at different stages of life
The evolution of children with premature adrenarche, with or without defects of cyp 21 gene
No full textAim of the study: In the present study we investigated concurrent alterations in oxidative stress, hormonal, metabolic, inflammatory, coagulation and endothelial dysfunction markers in girls with a history of PA, and their modification by the presence of CYP21A2 gene mutations. Patients - Methods: The study group included 45 adolescent girls with history of PA. In all subjects studied, the levels of glucose, insulin, lipids, androgens, oestrogens, cortisol, adiponectin, inflammation markers [TNFα, CRP, Interleukin-6 (IL-6), Endothelin (ET1)], coagulation factors [PAI-1, vWF, t-PA], total oxidative stress (TOS) and total antioxidative status (TAS) were determined. An ovarian ultrasound was carried in 35 girls with PA and all normal girls. Furthermore, the girls with a history of PA were divided in two subgroups, according to the presence or absence of CYP21A2 mutations. Group Α consisted of 29 girls without CYP21A2 mutation, while group Β consisted of 16 heterozygotes for CYP21A2 mutation. In addition to the evaluation described above, in all girls with PA an oral glucose tolerance test and GnRH-analog stimulation of the ovaries were carried out. Results: A) Comparing the total group of PA girls with their normal peers we found no difference in chronologic age, pubertal status, ΒΜΙ and waist to hip ratio. Also the two groups did not differ in the levels of oestrogens, cortisol, adiponectin, vWF, ET1, IL-6 and TNFα. However, girls with PA had higher levels of androgens, insulin resistance, CRP and PAI-1, while they had lower t-PA concentrations compared to controls. Additionaly, significant ovarian morphology abnormalities were observed in PA group. Although the total oxidative stress (TOS) and total antioxidant status (TAS) were comparable in PA girls and controls, CRP and PAI-1 values were positively correlated with TOS and t-PA values were positively correlated with TAS. It should be mentioned that TOS and TAS were unrelated to hyperandrogenism and insulin resistance. Β) Comparing the PA girls, with and without CYP21A2 mutation, it was found that the two groups did not differ in their chronological age, the age of pubarche, pubertal status, ΒΜΙ, waist to hip ratio, adiponectin, androgen levels, indices of insulin resistance (HOMA-IR, insulin/glucose, insulinogenic index, area under the curve for insulin, Matsuda index) and of glycemia (area under the curve for glucose). In addition, the levels of oxidative stress, inflammation markers (CRP, ET1, IL-6, TNFa) and the coagulation factors (vWF, tPA) did not differ in the two groups. The results of ovarian androgen production post GnRH-analog stimulation were comparable among the two groups. However, PAI-1 values were significantly higher and t-PA lower in non carriers than in carriers of CYP21A2 mutation, whereas Endothelin values were significantly lower in carriers of CYP21A2 mutations
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
Control of the onset of puberty
No full textPurpose of reviewThe mechanism of puberty initiation remains an enigma, despite extensive research in the field. Pulsatile pituitary gonadotropin secretion under the guidance of hypothalamic gonadotropin-releasing hormone (GnRH) constitutes a sine qua non for pubertal onset. In turn, the secretion of GnRH in the human hypothalamus is regulated by kisspeptin and its receptor as well as by permissive or opposing signals mediated by neurokinin B and dynorphin acting on their respective receptors. These three supra-GnRH regulators compose the Kisspeptin, Neurokinin B and Dynorhin neurons (KNDy) system, a key player in pubertal onset and progression.Recent findingsThe recent discovery that makorin ring finger protein 3 is also involved in puberty initiation provided further insights into the regulation of the KNDy pathway. In fact, the inhibitory (-amino butyric acid, neuropeptide Y, and RFamide-related peptide-3) and stimulatory signals (glutamate) acting upstream of KNDy called into question the role of makorin ring finger protein 3 as the gatekeeper of puberty. Meanwhile, the findings that neuroestradiol' produced locally and endocrine disruptors from the environment may influence GnRH secretion is intriguing. Finally, epigenetic mechanisms have been implicated in pubertal onset through recently discovered mechanisms.SummaryThe exact molecular machinery underlying puberty initiation in humans is under intensive investigation. In this review, we summarize research evidence in the field, while emphasizing the areas of uncertainty and underlining the impact of current information on the evolving theory regarding this fascinating phenomenon
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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