195 research outputs found
Increased adrenal steroid secretion in response to CRF in women with hypothalamic amenorrhea
Objectie: To evaluate adrenal steroid hormone secretion in response to corticotropin-releasing factor (CRF) or to adrenocorticotropin
hormone in women with hypothalamic amenorrhea. Design: Controlled clinical study. Setting: Department of
Reproductive Medicine and Child Development, Section of Gynecology and Obstetrics, University of Pisa, Italy. Patient(s):
Fifteen women with hypothalamic amenorrhea were enrolled in the study. Eight normal cycling women were used as control
group. Interention(s): Blood samples were collected before and after an injection of ovine CRF (0.1 g/kg iv bolus) or after
synthetic ACTH (0.25 mg iv). Main outcome measure(s): Plasma levels of ACTH, 17-hydroxypregnenolone (17OHPe), progesterone
(P), dehydroepiandrosterone (DHEA), 17-hydroxyprogesterone (17OHP), cortisol (F), 11-deoxycortisol (S) and androstenedione
(A). Result(s): Basal plasma concentrations of ACTH, cortisol, 11-deoxycortisol, DHEA and 17OHPe were significantly
higher in patients than in controls, whereas plasma levels of progesterone and 17-OHP were significantly lower in patients than
in controls. In amenorrheic women the ratio of 17-OHPe/DHEA, of 17-OHPe/17-OHP and of 11-deoxycortisol/cortisol were
significantly higher than in controls, while a significant reduction in the ratio of 17-OHP/androstenedione, of 17-OHP/11-deoxycortisol
was obtained. In response to corticotropin-releasing factor test, plasma levels of ACTH, cortisol, 17-OHP, 11-deoxycortisol,
DHEA and androstenedione were significantly lower in patients than in controls. In response to adrenocorticotropin
hormone, plasma levels of 17-OHP, androstenedione and androstenedione/cortisol were significantly higher in patients than in
controls. Conclusions: Patients suffering for hypothalamic amenorrhea showed an increased activation of hypothalamus-pituitaryadrenal
(HPA) axis, as shown by the higher basal levels and by augmented adrenal hormone response to corticotropin-releasing
factor administration. These data suggest a possible derangement of adrenal androgen enzymatic pathway
Nonparametric nonlinear model predictive control
Model Predictive Control (MPC) has recently found wide acceptance in industrial applications, but its potential has been much impeded by linear models due to the lack of a similarly accepted nonlinear modeling or databased technique. Aimed at solving this problem, the paper addresses three issues: (i) extending second-order Volterra nonlinear MPC (NMPC) to higher-order for improved prediction and control; (ii) formulating NMPC directly with plant data without needing for parametric modeling, which has hindered the progress of NMPC; and (iii) incorporating an error estimator directly in the formulation and hence eliminating the need for a nonlinear state observer. Following analysis of NMPC objectives and existing solutions, nonparametric NMPC is derived in discrete-time using multidimensional convolution between plant data and Volterra kernel measurements. This approach is validated against the benchmark van de Vusse nonlinear process control problem and is applied to an industrial polymerization process by using Volterra kernels of up to the third order. Results show that the nonparametric approach is very efficient and effective and considerably outperforms existing methods, while retaining the original data-based spirit and characteristics of linear MPC
Preoperative rectal cancer staging with phased-array MR
<p>Abstract</p> <p>Background</p> <p>We retrospectively reviewed magnetic resonance (MR) images of 96 patients with diagnosis of rectal cancer to evaluate tumour stage (T stage), involvement of mesorectal fascia (MRF), and nodal metastasis (N stage).</p> <p>Our gold standard was histopathology.</p> <p>Methods</p> <p>All studies were performed with 1.5-T MR system (Symphony; Siemens Medical System, Erlangen, Germany) by using a phased-array coil. Our population was subdivided into two groups: the first one, formed by patients at T1-T2-T3, N0, M0 stage, whose underwent MR before surgery; the second group included patients at Tx N1 M0 and T3-T4 Nx M0 stage, whose underwent preoperative MR before neoadjuvant chemoradiation therapy and again 4-6 wks after the end of the treatment for the re-staging of disease.</p> <p>Our gold standard was histopathology.</p> <p>Results</p> <p>MR showed 81% overall agreement with histological findings for T and N stage prediction; for T stage, this rate increased up to 95% for pts of group I (48/96), while for group II (48/96) it decreased to 75%.</p> <p>Preoperative MR prediction of histologically involved MRF resulted very accurate (sensitivity 100%; specificity 100%) also after chemoradiation (sensitivity 100%; specificity 67%).</p> <p>Conclusions</p> <p>Phased-array MRI was able to clearly estimate the entire mesorectal fat and surrounding pelvic structures resulting the ideal technique for local preoperative rectal cancer staging.</p
The impact of antiandrogen 2-hydroxyflutamide on the expression of steroidogenic enzymes in cultured porcine ovarian follicles
Social change and the family: Comparative perspectives from the west, China, and South Asia
This paper examines the influence of social and economic change on family structure and relationships: How do such economic and social transformations as industrialization, urbanization, demographic change, the expansion of education, and the long-term growth of income influence the family? We take a comparative and historical approach, reviewing the experiences of three major sociocultural regions: the West, China, and South Asia. Many of the changes that have occurred in family life have been remarkably similar in the three settingsâthe separation of the workplace from the home, increased training of children in nonfamilial institutions, the development of living arrangements outside the family household, increased access of children to financial and other productive resources, and increased participation by children in the selection of a mate. While the similarities of family change in diverse cultural settings are striking, specific aspects of change have varied across settings because of significant pre-existing differences in family structure, residential patterns of marriage, autonomy of children, and the role of marriage within kinship systems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45661/1/11206_2005_Article_BF01124383.pd
Venous thrombosis and hormonal contraception: what's new with estradiol-based hormonal contraceptives?
Franca Fruzzetti,1 Angelo Cagnacci2 1Department of Obstetrics and Gynaecology, Santa Chiara Hospital, University of Pisa, Pisa, Italy; 2Institute of Obstetrics and Gynecology, Department of Medical Area, University of Udine, Udine, Italy Objective: Estradiol (E2)-based hormonal contraceptives impact less than ethinylstradiol (EE) contraceptives on venous thromboembolism (VTE) in comparison to formulations with EE.Study design: In this article, the pharamacologic data of EE and E2 were briefly reviewed, along with the induced biologic effect. These data were then related to a recent large international prospective, controlled, non-interventional cohort active surveillance study, on the cardiovascular risk of users of different types of combined estro-progestin contraceptive (CEPC).Results: The crude HR for E2-valerate (E2V)/dienogest vs other CEPCs with EE was 0.8 (95% CI, 0.4–1.6), but when the data were corrected for age, body mass index, duration of use, and family history of VTE, the corresponding adjusted HR was 0.5 (95% CI, 0.2–1.0). A comparison of the E2V/dienogest and EE/levonorgestrel groups showed that the two contraceptives induced a similar VTE risk with the crude and adjusted VTE HRs of 0.7 (95% CI, 0.3–1.8) and 0.5 (95% CI, 0.2–1.3), respectively. Similar results were obtained when the observation was prolonged to January 2017.Conclusions: The reduced impact of E2 vs EE on coagulation translates into the epidemiologic evidence of a reduced number of events in E2V vs EE users, when progestins other than levonorgestrel are used. However, E2 may continue to negatively impact on the risk of VTE, and this should not be forgotten at the time of prescription. Family history of VTE or thrombophilia, age, and obesity are risk factors for VTE too. If these risk factors are not taken into consideration and excluded, they can overcome or hide the higher safety of E2 vs CEPCs with EE. Keywords: estradiol, estradiol valerate, contraception, venous thromboembolism, dienoges
Diagnosis of a variant of Mayer-Rokitansky-Kuster-Hauser syndrome: useful MRI findings
Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome consists of vaginal aplasia associated with other mĂŒllerian duct abnormalities. Its penetrance varies, as does the involvement of other organ systems. Type I MRKU syndrome is characterized by an isolated absence of the proximal two thirds of the vagina, whereas type II is marked by other malformations which include vertebral, cardiac, urologic (upper tract), and otologic anomalies. In both types, the extent of vaginal aplasia varies, ranging from virtually absent to a length much more inferior than the normal one (2-5 cm). MRKU syndrome usually remains undetected until the patient presents with primary amenorrhea despite normal female sexual development. It is important to underline the fact that this syndrome is the second most common cause of primary amenorrhea. Although this condition has psychologically devastating consequences, its anatomical defects can be surgically treated. In fact, following diagnosis, surgery allows patients to have normal sexual function while reproduction may be possible if assisted techniques are performed
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