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1.
Hum Reprod ; 28(12): 3292-300, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24052503

ABSTRACT

STUDY QUESTION: Is there a shift in the timing of nucleolar channel system (NCS) formation following controlled ovarian hyperstimulation (COH)? SUMMARY ANSWER: NCSs appear prematurely following COH compared with natural cycles. WHAT IS KNOWN ALREADY: During natural cycles, NCSs of endometrial epithelial cell (EEC) nuclei are exclusively present during the window of implantation and are uniformly distributed throughout the upper endometrial cavity. STUDY DESIGN, SIZE, DURATION: Prospective two-cohort study. Cohorts I and II each consisted of seven volunteers for the duration of three menstrual study cycles that were separated by at least one wash-out or rest cycle, between December 2008 and May 2012. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were recruited from a pool of healthy oocyte donors. Consecutive endometrial biopsies were obtained during the same luteal phase on cycle days (CD) 16, 20 and 26 for Cohort I, and on CD14, 22 and 24 for Cohort II, following random assignment to a natural cycle group, a COH cycle group (using a GnRH antagonist), or a COH cycle group receiving luteal phase hormonal supplementation (COH + S). The day of oocyte retrieval was designated CD14 in COH cycles and the day of the LH surge was designated CD13 in natural cycles. Prevalence of NCSs in the nuclei of EECs was quantified using indirect immunofluorescence with an antibody directed against a subset of related nuclear pore complex proteins that are major constituents of NCSs. Progesterone and estradiol levels were measured on the day of each endometrial biopsy. MAIN RESULTS AND THE ROLE OF CHANCE: The natural cycle group exhibited peak NCS prevalence on CD20 [53.3%; interquartile range (IQR) 28.5-55.8], which rapidly declined on CD22 (11.8%; IQR 6.3-17.6), CD24 (2.5%; IQR 0.0-9.2) and CD26 (0.3%; IQR 0.0-3.5), and no NCSs on CD14 and 16 defining a short NCS window around CD20. In contrast, in COH and COH + S cycles, NCS prevalence was high already on CD16 (40.4%; IQR 22.6-53.4 and 35.6%; IQR 26.4-44.5, respectively; P = 0.001 compared with CD16 of the natural cycle group, Mann-Whitney), whereas no significant difference in NCS prevalence was detected on any of the other five CDs between the three groups (P > 0.05). LIMITATIONS, REASONS FOR CAUTION: The cohort size was small (n = 7) but was offset by the all-or-none presence of NCSs on CD16 in natural versus COH and COH + S cycles and the fact that each subject served as her own control. WIDER IMPLICATIONS OF THE FINDINGS: Premature appearance of NCSs and hence maturation of the endometrium following COH is consistent with previous studies based on histological dating but contradicts studies based on mRNA expression profiling, which reported a lag in endometrial maturation. However, this is the first study of this kind that is based on consecutive endometrial biopsies within the same cycle and that reports such clear-cut differences: no versus robust NCS presence on CD16. Our observation of advanced endometrial maturation following COH may contribute to the reduced implantation rates seen in fresh compared with frozen and donor IVF-embryo transfer cycles. Therefore, the NCS window could serve as a sensitive guide for timing of embryo transfer in frozen and donor cycles. STUDY FUNDING/COMPETING INTEREST(S): The study was supported by the March of Dimes Birth Defects foundation (1-FY09-363 to U.T.M.); Ferring Pharmaceuticals, Parsippany, NJ; East Coast Fertility, Plainview, NY and the CMBG Training Program (T32 GM007491 to M.J.S.). We report no competing interests.


Subject(s)
Cell Nucleolus/physiology , Endometrium/physiology , Ovulation Induction , Embryo Implantation , Female , Humans , Luteal Phase , Oocyte Donation , Organelles/physiology , Progesterone/metabolism
2.
J Perinatol ; 29(11): 721-5, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19861969

ABSTRACT

Respect for patient autonomy remains a foundational principle guiding the ethical practice of medicine-a mission first articulated by Hippocrates. Damocles, another figure from ancient Greece, provides a useful parable for describing performance under distress: Damocles loses his desire for opulence and power when he notices a sword dangling precariously above his head. Contemporary obstetricians deciding whether to forestall or impose major abdominal surgery on parturients entrusted to their care struggle valiantly in the chasm dividing Hippocratic idealism from the economic realism driven by the medicolegal sword of Damocles. Given the inherent risk of unforeseeable and unsalvageable fetal catastrophe during labor and vaginal delivery, and the often unsubstantiated, yet automatic, allegation of negligence that follows a labor-associated adversity, obstetricians-and their liability insurance carriers-have recalibrated obstetric practice in alignment with the increasingly risk-averse preferences of most patients. Indeed, less intrapartum risk for patients and less corresponding medicolegal exposure for obstetricians help explain the rising cesarean delivery rate and, more importantly, the steady disappearance of higher-risk interventions such as vaginal birth after cesarean (VBAC). Is this increasing reluctance to offer VBAC supervision ethically defensible? This paper argues that it is. Fiduciary professionalism mandates physician self-sacrifice, not self-destruction; a VBAC gone awry without negligence or substandard care may, nevertheless, render future affordable liability coverage unattainable. Yet, the unavailability of VBAC infringes on the autonomy of women who want to assume the intrapartum risks of a VBAC in lieu of a repeat cesarean delivery. The proposed solution is the regionalization of VBAC care provision in designated medical centers and/or the implementation of binding arbitration in an ethical trade-off to enhance patient autonomy regarding the preferred mode of delivery despite parallel constraint on legal options.


Subject(s)
Cesarean Section/economics , Hippocratic Oath , Malpractice/economics , Obstetrics/economics , Personal Autonomy , Practice Patterns, Physicians'/economics , Cesarean Section/ethics , Cesarean Section, Repeat/economics , Cesarean Section, Repeat/ethics , Cost-Benefit Analysis/ethics , Defensive Medicine/economics , Defensive Medicine/ethics , Ethics, Medical , Female , Humans , Infant, Newborn , Insurance, Liability/economics , Insurance, Liability/ethics , Obstetrics/ethics , Practice Patterns, Physicians'/ethics , Pregnancy , Risk Factors , Risk Management/economics , Risk Management/ethics , United States , Vaginal Birth after Cesarean/economics , Vaginal Birth after Cesarean/ethics
3.
Lik Sprava ; (3-4): 94-8, 1996.
Article in Russian | MEDLINE | ID: mdl-9035895

ABSTRACT

A study was made of the labour conditions of those workers engaged in the production of basalt fibre (BF). Morphological makeup is examined as is dispersity and cytotoxicity of the dust produced in the process of BF making. An issue is addressed of usefulness of setting special hygienic regulations for BF dust.


Subject(s)
Construction Materials/adverse effects , Dust/adverse effects , Minerals/adverse effects , Silicates/adverse effects , Air Pollutants, Occupational/adverse effects , Air Pollutants, Occupational/toxicity , Animals , Cells, Cultured , Construction Materials/toxicity , Dose-Response Relationship, Drug , Embryo, Mammalian , Fibroblasts/cytology , Fibroblasts/drug effects , Humans , Maximum Allowable Concentration , Mice , Minerals/toxicity , Occupational Exposure/adverse effects , Particle Size , Silicates/toxicity
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