The Mare as a Model for Luteinized Unruptured Follicle Syndrome: Intrafollicular Endocrine Milieu.

Luteinized unruptured follicle (LUF) syndrome is a recurrent anovulatory dysfunction that affects up to 23% of women with normal menstrual cycles and up to 73% with endometriosis. Mechanisms underlying the development of LUF syndrome in mares were studied to provide a potential model for human anovulation. The effect of extended increase in circulating LH achieved by administration of recombinant equine LH (reLH) or a short surge of LH and decrease in progesterone induced by prostaglandin F2α (PGF2α) on LUF formation (Experiment 1), identification of an optimal dose of COX-2 inhibitor (flunixin meglumine, FM; to block the effect of prostaglandins) for inducing LUFs (Experiment 2), and evaluation of intrafollicular endocrine milieu in LUFs (Experiment 3) were investigated. In Experiment 1, mares were treated with reLH from Day 7 to Day 15 (Day 0=ovulation), PGF2α on Day 7, or in combination. In Experiment 2, FM at doses of 2.0 or 3.0 mg/kg every 12 h and human chorionic gonadotropin (hCG) (1500 IU) were administered after a follicle ≥32 mm was detected. In Experiment 3, FM at a dose of 2.0 mg/kg every 12 h plus hCG was used to induce LUFs and investigate the intrafollicular endocrine milieu. No LUFs were induced by reLH or PGF2α treatment; however, LUFs were induced in 100% of mares using FM. Intrafollicular PGF2α metabolite, PGF2α, and PGE2 were lower and the ratio of PGE2:PGF2α was higher in the induced LUF group. Higher levels of intrafollicular E2 and total primary sex steroids were observed in the induced LUF group along with a tendency for higher levels of GH, cortisol, and T; however, LH, PRL, VEGF-A, and NO did not differ between groups. In conclusion, this study reveals part of the intrafollicular endocrine milieu and the association of prostaglandins in LUF formation, and indicates that the mare might be an appropriate model for studying the poorly understood LUF syndrome

The Mare as a Model for Luteinized Unruptured Follicle Syndrome: Intrafollicular Endocrine Milieu.

Luteinized unruptured follicle (LUF) syndrome is a recurrent anovulatory dysfunction that affects up to 23% of women with normal menstrual cycles and up to 73% with endometriosis. Mechanisms underlying the development of LUF syndrome in mares were studied to provide a potential model for human anovulation. The effect of extended increase in circulating LH achieved by administration of recombinant equine LH (reLH) or a short surge of LH and decrease in progesterone induced by prostaglandin F2α (PGF2α) on LUF formation (Experiment 1), identification of an optimal dose of COX-2 inhibitor (flunixin meglumine, FM; to block the effect of prostaglandins) for inducing LUFs (Experiment 2), and evaluation of intrafollicular endocrine milieu in LUFs (Experiment 3) were investigated. In Experiment 1, mares were treated with reLH from Day 7 to Day 15 (Day 0=ovulation), PGF2α on Day 7, or in combination. In Experiment 2, FM at doses of 2.0 or 3.0 mg/kg every 12 h and human chorionic gonadotropin (hCG) (1500 IU) were administered after a follicle ≥32 mm was detected. In Experiment 3, FM at a dose of 2.0 mg/kg every 12 h plus hCG was used to induce LUFs and investigate the intrafollicular endocrine milieu. No LUFs were induced by reLH or PGF2α treatment; however, LUFs were induced in 100% of mares using FM. Intrafollicular PGF2α metabolite, PGF2α, and PGE2 were lower and the ratio of PGE2:PGF2α was higher in the induced LUF group. Higher levels of intrafollicular E2 and total primary sex steroids were observed in the induced LUF group along with a tendency for higher levels of GH, cortisol, and T; however, LH, PRL, VEGF-A, and NO did not differ between groups. In conclusion, this study reveals part of the intrafollicular endocrine milieu and the association of prostaglandins in LUF formation, and indicates that the mare might be an appropriate model for studying the poorly understood LUF syndrome

Dominant follicle growth patterns and associated endocrine dynamics in anovulatory and ovulatory waves in women

Growth patterns and associated endocrine profiles were compared between dominant anovulatory (ADF) and ovulatory follicles (OvF) developing from different waves within and between menstrual cycles in women. Follicular mapping profiles of 49 healthy women of reproductive age and blood samples were obtained every 1–3 days during one interovulatory interval. Sixty-three dominant follicles were classified into wave 1 (W1ADF; n = 8) and wave 2 (W2ADF; n = 6) anovulatory follicles and wave 2 (W2OvF; n = 33) and wave 3 (W3OvF; n = 16) ovulatory follicles. Comparisons were made between W1ADF and W2ADF, W2ADF and W2OvF, and W2OvF and W3OvF. The waves were numbered 1, 2, or 3 based on when the waves emerged relative to the preceding ovulation. W1ADF emerged closer to the preceding ovulation, and W2ADF emerged in the late luteal or early follicular phase. The interval from emergence to maximum diameter was shorter for W2ADF than W1ADF and for W3OvF than W2OvF. Selection of W3OvF occurred at a smaller diameter compared to W2OvF. W1ADF regressed at a faster rate than W2ADF. Also, W1ADF were associated with lower mean follicle stimulating hormone (FSH) and higher mean estradiol than W2ADF. In contrast, W3OvF were associated with higher FSH and luteinizing hormone (LH) compared to W2OvF. However, W2OvF were associated with higher progesterone than W3OvF. This study contributes to the understanding of the physiologic mechanisms underlying selection of the dominant follicle, ovulation, and pathophysiology of anovulation in women, as well as optimization of ovarian stimulation protocols for assisted reproduction

The metric and strong coupling limit of the M5-brane

We find the analogue of the Boillat metric of Born-Infeld theory for the M5-brane. We show that it provides the propagation cone of {\sl all} 5-brane degrees. In an arbitrary background field, this cone never lies outside the Einstein cone. An energy momentum tensor for the three-form is defined and shown to satisfy the Dominant Energy Condition. The theory is shown to be well defined for all values of the magnetic field but there is a limiting electric field strength. We consider the strong coupling limit of the M5-brane and show that the corresponding theory is conformally invariant and admits infinitely many conservation laws. On reduction to the Born-Infeld case this agrees with the work of Bia{\l}nicki-Birula.Comment: Version to be published in special issue of JMP, July 2001. Sections 8 and 9 have been remove

On the underlying gauge group structure of D=11 supergravity

The underlying gauge group structure of D=11 supergravity is revisited (see paper for detailed abstract).Comment: 16 pages, no figure

BPS states in M-theory and twistorial constituents

We provide a complete algebraic description of BPS states in M-theory in terms of primary constituents that we call BPS preons. We argue that any BPS state preserving $k$ of the 32 supersymmetries is a composite of (32-k) BPS preons. In particular, the BPS states corresponding to the basic M2 and M5 branes are composed of 16 BPS preons. By extending the M-algebra to a generalized D=11 conformal superalgebra $osp(1|64)$ we relate the BPS preons with its fundamental representation, the D=11 supertwistors.Comment: 4 pages. Refs. updated, two cosmetic changes, to appear in PR

Patient and provider experiences with virtual care during the COVID-19 pandemic: A mixed methods study

The COVID-19 pandemic prompted the rapid uptake of Virtual Care (VC). Positive patient outcomes with VC are previously reported but little is known about the experiences of patients and providers using VC during the pandemic. We aimed to describe patient and primary care provider experiences, satisfaction, perceptions, and attitudes to VC during the COVID-19 pandemic that might explain adoption of VC across the continuum of care and inform sustained uptake. We conducted a sequential explanatory mixed methods study using online surveys and virtual interviews with a convenience sample of primary care providers and patients in a Canadian province (July – December 2020). Eligible participants included patients and primary care providers using VC during the COVID-19 pandemic. Survey responses and interviews were analyzed using descriptive statistics and thematic analysis, respectively. Overall satisfaction was compared using the Mann-Whitney U test. Eighty-five patients and 94 primary care providers responded to the surveys. Patients reported higher overall satisfaction with VC than primary care providers (median [interquartile range]: 4.4 [4.0-4.7] and 3.7 [3.4-3.9] p \u3c 0.001). Ten patients and 11 primary care providers were interviewed. Both groups strongly appreciated VC’s increased access and convenience, identified the lack of compensation as a pre-pandemic barrier to providing VC, and reported willingness to continue VC post-COVID-19 pandemic. The COVID-19 pandemic provided an opportunity for patients and primary care providers to rapidly adopt VC with high satisfaction. Patients and primary care providers viewed VC positively due to its convenience and accessibility; both intend to continue using VC post-pandemic. Experience Framework This article is associated with the Staff & Provider Engagement lens of The Beryl Institute Experience Framework (https://www.theberylinstitute.org/ExperienceFramework). Access other PXJ articles related to this lens. Access other resources related to this lens

G-Structures, Fluxes and Calibrations in M-Theory

We study the most general supersymmetric warped M-theory backgrounds with non-trivial G-flux of the type R^{1,2} x M_8 and AdS_3 x M_8. We give a set of necessary and sufficient conditions for preservation of supersymmetry which are phrased in terms of G-structures and their intrinsic torsion. These equations may be interpreted as calibration conditions for a static ``dyonic'' M-brane, that is, an M5-brane with self-dual three-form turned on. When the electric flux is turned off we obtain the supersymmetry conditions and non-linear PDEs describing M5-branes wrapped on associative and special Lagrangian three-cycles in manifolds with G_2 and SU(3) structures, respectively. As an illustration of our formalism, we recover the 1/2-BPS dyonic M-brane, and also construct some new examples.Comment: 40 pages; v2: one reference added, typos correcte