Pulsatile secretion of LH and FSH was examined to determine if the frequency of LH pulses, and by inference pulsatile GnRH secretion, varied during the human menstrual cycle. Blood samples were obtained at 10- or 20-min intervals for 12 or 24 h at 7-day intervals during the same ovulatory cycle in eight normal women. Ovarian steroids showed the expected cyclical changes and mean plasma FSH concentrations showed an inverse relationship to estradiol, being low when estradiol was greater than 150 pg/ml. Sampling every 10 min revealed a constant LH pulse amplitude but LH pulse frequency increased (from 11.8 to 14.3 pulses/12 h) during the follicular phase. LH pulse frequency was not further increased in two women sampled during the LH surge, but pulse amplitude was markedly higher. During the luteal phase LH pulse frequency was reduced to eight pulses/12 h but frequency was more variable between subjects than in the follicular phase. LH pulse amplitude showed striking variation (0.8-29.4 mIU/ml) during the luteal phase of the cycle and large LH secretory episodes which lasted 1-3 h were irregularly interspersed among periods of low amplitude LH secretion. These data show that the frequency of LH pulses, and by inference GnRH secretion, varies during the menstrual cycle but the degree of change is less than reported in previous studies. This observation may explain the reported efficacy of fixed frequency GnRH regimes in inducing ovulation and cyclical ovarian function.
BackgroundRecruiting pediatric samples for research may be challenging due to parental mistrust of the research process, privacy concerns, and family time constraints. Recruitment of children with chronic and genetic conditions may further complicate the enrollment process.ObjectiveIn this paper, we describe the methodological challenges of recruiting children for research and provide an exemplar of how the use of information technology (IT) strategies with social networking may improve access to difficult-to-reach pediatric research participants.MethodsWe conducted a cross-sectional descriptive study of boys between the ages of 8 and 18 years with Klinefelter syndrome. This study presented unique challenges for recruitment of pediatric participants. These challenges are illustrated by the report of recruitment activities developed for the study. We reviewed the literature to explore the issues of recruiting children for research using conventional and IT approaches. Success rates of conventional recruitment approaches, such as brochures, flyers in medical offices, and physician referrals, are compared with IT-based outreach. The IT approaches included teleconferencing via a Klinefelter syndrome support group, services of a Web-based commercial recruitment-matching company, and the development of a university-affiliated research recruitment website with the use of paid advertising on a social networking website (Facebook).ResultsOver a 3-month period, dissemination of over 150 recruitment brochures and flyers placed in a large urban hospital and hospital-affiliated clinical offices, with 850 letters to physicians and patients were not successful. Within the same period, face-to-face recruitment in the clinical setting yielded 4 (9%) participants. Using Web-based and social networking approaches, 39 (91%) agreed to participate in the study. With these approaches, 5 (12%) were recruited from the national Klinefelter syndrome advocacy group, 8 (19%) from local and teleconference support groups, 10 (23%) from a Web-based research recruitment program, and 16 (37%) from the university-affiliated recruitment website. For the initial 6 months, the university website was viewed approximately 2 to 3 times per day on average. An advertisement placed on a social networking site for 1 week increased website viewing to approximately 63 visits per day. Out of 112 families approached using all of these methods, 43 (38%) agreed to participate. Families who declined cited either travel distance to the study site (15, 22%) or unwillingness to disclose the Klinefelter syndrome diagnosis to their sons (54, 78%) as the reasons for nonparticipation.ConclusionsUse of Web-based technologies enhances the recruitment of difficult-to-reach populations. Of the many approaches employed in this study, the university-affiliated recruitment website supported by a Facebook advertisement appeared to be the most successful. Research grant budgets should include expenses for website registration and maintenance fees as well as online advertisements ...
Objective-Cognitive benefit of postmenopausal hormone use is controversial; however, timing treatment close to menopause may increase the likelihood of preserving cognitive function. We examined effects of early-initiation hormone use on visual working memory, hypothesizing that longterm hormone use is associated with greater brain activation during visual working memory.Methods-This is a cross-sectional comparison of long-term early hormone users -current (n=13) and past (n=24, 2.1±1.0 years off hormones) -to never-users (n=18), using a visual memory task and functional MRI. We evaluated 55 women over age 60 at the University of Michigan's General Clinical Research Center. Hormone users had completed at least ten continuous years of conjugated equine estrogens with or without medroxyprogesterone acetate, began within two years of menopause. Women were excluded for illness, medication, intermittent estrogen use, phytoestrogen use, recent smoking, and MRI contraindications. The primary outcome was functional MRI-detected brain activity during the visual memory task.Results-Compared to never-users, both hormone-user groups had increased activation in the frontal and parietal cortices, insula, hippocampus, and cingulate; combined hormone-users also had increased activation in the putamen and raphe (corrected p<0.05 or uncorrected p<0.001 with a priori hypothesis). Across the entire sample, medial temporal cortex (p<0.000 right; p<0.018 left) and right hippocampus (p<0.000) positively correlated with task performance. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Conflicts of Interest & DisclosuresThe authors have nothing to disclose NIH Public Access Author ManuscriptMenopause. Author manuscript; available in PMC 2011 July 1. Published in final edited form as:Menopause. 2010 July ; 17(4): 692-699. doi:10.1097/gme.0b013e3181cc49e9. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author ManuscriptConclusions-Hormone use was associated with increased brain activation during the visual memory task, in regions used for visual working memory. A positive correlation between activation and task performance suggests that early-initiated long-term postmenopausal hormone use may benefit visual working memory.
The lack of a consistent, well-defined measurement of OC use limits our understanding of contraceptive misuse and related negative outcomes. Future research should clarify terminology, develop standardized measures, incorporate multimethod approaches with innovative methods, and publish details of measurement methods.
Depending on the degree of phenotypic abnormality, boys with KS may be at risk for impaired QOL. Testosterone levels were not shown to influence psychosocial health. The Klinefelter Phenotype Index Scale may be a useful tool to characterize KS features in boys.
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