Anti-müllerian hormone is not associated with cardiometabolic risk factors in adolescent females

<p>Objectives: Epidemiological evidence for associations of Anti-Müllerian hormone (AMH) with cardiometabolic risk factors is lacking. Existing evidence comes from small studies in select adult populations, and findings are conflicting. We aimed to assess whether AMH is associated with cardiometabolic risk factors in a general population of adolescent females.</p> <p>Methods: AMH, fasting insulin, glucose, HDLc, LDLc, triglycerides and C-reactive protein (CRP) were measured at a mean age 15.5 years in 1,308 female participants in the Avon Longitudinal Study of Parents and Children (ALSPAC). Multivariable linear regression was used to examine associations of AMH with these cardiometabolic outcomes.</p> <p>Results: AMH values ranged from 0.16–35.84 ng/ml and median AMH was 3.57 ng/ml (IQR: 2.41, 5.49). For females classified as post-pubertal (n = 848) at the time of assessment median (IQR) AMH was 3.81 ng/ml (2.55, 5.82) compared with 3.25 ng/ml (2.23, 5.05) in those classed as early pubertal (n = 460, P≤0.001). After adjusting for birth weight, gestational age, pubertal stage, age, ethnicity, socioeconomic position, adiposity and use of hormonal contraceptives, there were no associations with any of the cardiometabolic outcomes. For example fasting insulin changed by 0% per doubling of AMH (95%CI: −3%,+2%) p = 0.70, with identical results if HOMA-IR was used. Results were similar after additional adjustment for smoking, physical activity and age at menarche, after exclusion of 3% of females with the highest AMH values, after excluding those that had not started menarche and after excluding those using hormonal contraceptives.</p> <p>Conclusion: Our results suggest that in healthy adolescent females, AMH is not associated with cardiometabolic risk factors.</p&gt

Correlation between three assay systems for anti-Mullerian hormone (AMH) determination

PURPOSE: Analysis of anti-Müllerian hormone (AMH) is becoming of recognized importance in reproductive medicine, but assays are not standardized. We have evaluated the correlation between the new Gen II ELISA kit (Beckman-Coutler) and the older ELISA kits by Immunotech (IOT) and Diagnostic Systems Laboratories (DSL). METHODS: A total of 56 archived serum samples from patients with subfertility or reproductive endocrine disorders were retrieved and assayed in duplicate using the three AMH ELISA kits . The samples covered a wide range of AMH concentrations (1.9 to 142.5 pmol/L). RESULTS: We observed good correlations between the new (AMH Gen II) and old AMH assay kits by IOT and DSL (R(2) = 0.971 and 0.930 respectively). The regression equations were AMH (Gen II) = 1.353 × AMH (IOT) + 0.051 and AMH (Gen II) = 1.223 × AMH (DSL) – 1.270 respectively. CONCLUSIONS: AMH concentrations using the Gen II kit are slightly higher than those from the IOT and DSL kits. Standardization of assay results worldwide is urgently required but this analysis facilitates the interpretation of values obtained historically and in future studies using any of the 3 assays available. Meanwhile, adapting clinical cut-offs from previously published work by direct conversion is not recommended

Occupational Stress Risk Assessment: AACE Ambulance Trust. Phase 1 summary findings – Focus groups with control room employees

Key Points: This project commissioned by the Association of Ambulance Chief Executives (AACE) aims to explore the sources of stress risks in the control rooms.Phase 1 took place between Dec 2023 and March 2024. Eight focus groups were conducted across four English ambulance trusts, with a total of 29 participants.Through these groups, key causes and consequences of stress were identified – some aligning with the HSE’s Management Standard framework, others unique and specific to the control room work environment.National-level challenges were identified with the current NHS and health context influencing the experiences of control room employees.Overall, findings highlight issues with: (1) Works demands and limited resources to address them; (2) Varied management support; (3) Overall negativity that can affect the work atmosphere, and culture around mental health; (4) Frequent changes in protocols with limited communication; (5) Work-life balance struggles

Modélisation multiéchelle de l'influence de la texture morphologique sur l'analyse des contraintes en diffraction des rayons X et des neutrons

La présence de contraintes résiduelles dans un matériau modifie fortement ses applications de même que sa durée de vie en service. Cette problématique est fondamentale car la réponse mécanique d’un matériau ne dépend pas seulement de la sollicitation appliquée mais également de l’état mécanique interne de celui-ci en lien avec la microstructure. Parmi les techniques de détermination des contraintes résiduelles dans les matériaux cristallins, la diffraction des rayons X (ou des neutrons) occupe une place toute particulière. Elle permet d’évaluer les contraintes internes, en les reliant aux déformations mesurées à l’aide des équations de l’élasticité. La microstructure conditionne largement les propriétés élastiques des matériaux. La détermination rigoureuse de ces propriétés est indispensable pour une analyse juste des contraintes résiduelles du matériau. L’influence de la texture cristallographique dans la détermination des contraintes résiduelles par diffraction a fait l’objet de nombreux travaux de recherches, sans pour autant que l’on se soit intéressé aux effets de la texture morphologique. Nous avons étudié l’influence de la texture morphologique sur la détermination des contraintes résiduelles par diffraction dans les matériaux métalliques de symétrie cubique et hexagonale, monophasés et biphasés. Pour cela, un modèle autocohérent élastique a été développé afin de prendre en compte la texture morphologique. Plusieurs morphologies (sphère, fibre et disque) ont été étudiées, puis couplées avec la texture cristallographique afin de rendre compte de l’effet combiné des textures morphologique et cristallographique en élasticité. Dans le cas de la texture morphologique, une influence plus marquée que la texture cristallographique, en termes de propriétés macroscopiques mais aussi en termes de contraintes résiduelles (plusieurs dizaines de MPa de différence) a été observée. En effet, l’anisotropie introduite par la texture morphologique modifie les courbes en sin2ψ. L’interprétation de ces dernières en termes de contraintes conduit à des valeurs très éloignées des contraintes réelles dans le matériau

Nonlinear acoustics in brass instruments using 2D complex modal bases

The modelling approach presented here aims at developing accurate, yet computationally efficient, numerical models of brass instrument resonators including nonlinear propagation, viscothermal losses and radiation effects in 2D axisymmetric domains. The central idea is to bridge the refined accuracy of 2D models with the efficiency of reduced-order modal approaches. To model the nonlinear acoustic propagation inside the resonator, we propose the use of the Blackstock equation, a more appropriate choice when dealing with nonlinear standing wave motion, compared to the more commonly used Burgers equation. The first step of the approach consists in obtaining a complex modal basis from a 2D axisymmetric finite element model of the linearized equations. Here, a bounded domain outside the resonator, with a nonreflecting boundary condition, is included to explicitly account for 2D radiation effects. Moreover, the effects of the viscothermal boundary layers at the interior walls are modelled efficiently through an impedance boundary condition. The Blackstock equation is then projected onto the resulting 2D complex modal basis, leading to a compact set of nonlinear ordinary differential equations (ODEs) that can be truncated at any suitable number of terms. This leads to exploitable reduced formulations, adapted to quick temporal simulations, bifurcation analysis or parametric studies, retaining nevertheless the accuracy provided by 2D axisymmetric models. Additionally, the explicit account of the exterior acoustic field allows for the calculation of radiated sound pressures as well as directivity patterns, contrary to typical 1D models. Experimental validation and illustrative numerical results are presented for a simplified trumpet geometry in both linear and nonlinear scenarios, highlighting the benefits of the proposed approach

Étude du gradient de contraintes dans un alliage de zirconium : modèle de transition d'échelles et DRX en faible incidence

Les alliages de zirconium, de structure cristallographique hexagonale, présentent une forte anisotropie plastique tant au niveau macroscopique que mésoscopique (échelle des grains). Ces propriétés et l’existence d’une texture cristallographique expliquent l’apparition et le développement de gradient de contraintes résiduelles quand ces matériaux sont soumis à une déformation élastoplastique suite aux différentes étapes du procédé de fabrication. Pour étudier ce comportement, des éprouvettes de zircaloy-4 ont été soumises à des essais de laminage, à température ambiante, à divers taux de déformation imposés afin de suivre l’évolution des contraintes résiduelles en épaisseur. Une méthode d’analyse du gradient de contraintes par diffraction des rayons X (DRX) en faible incidence (méthode « multi-réflexion ») a été développée pour quantifier l’état mécanique pour différentes profondeurs en variant l’angle d’incidence. Les mesures, qui permettent d’accéder à des informations sur l’état mécanique mésoscopique des matériaux, confirment la présence d’une hétérogénéité marquée des contraintes d’ordre II. Un couplage entre les résultats expérimentaux et une modélisation autocohérente élastoplastique polycristalline a permis d’étudier l’influence des différentes sources d’hétérogénéités responsables de l’apparition des contraintes internes. Plus spécifiquement, la méthode que nous avons utilisée dans ce travail permet d’évaluer l’amplitude des contraintes du premier et du deuxième ordre dues aux incompatibilités de déformation plastique en utilisant les informations du modèle d’homogénéisation choisi. Cette étude montre que la valeur de la composante due aux incompatibilités de déformation plastique est importante et joue un rôle essentiel dans l’interprétation correcte des contraintes résiduelles analysées par diffraction

Good practice recommendations for the use of time-lapse technology†

STUDY QUESTION: What recommendations can be provided on the approach to and use of time-lapse technology (TLT) in an IVF laboratory?SUMMARY ANSWER: The present ESHRE document provides 11 recommendations on how to introduce TLT in the IVF laboratory. WHAT IS KNOWN ALREADY: Studies have been published on the use of TLT in clinical embryology. However, a systematic assessmentof how to approach and introduce this technology is currently missing.STUDY DESIGN, SIZE, DURATION: A working group of members of the Steering Committee of the ESHRE Special Interest Group in Embryology and selected ESHRE members was formed in order to write recommendations on the practical aspects of TLT for the IVF laboratory.PARTICIPANTS/MATERIALS, SETTING, METHODS: The working group included 11 members of different nationalities with internationally recognized experience in clinical embryology and basic science embryology, in addition to TLT. This document is developed according to the manual for development of ESHRE recommendations for good practice. Where possible, the statements are supported by studies retrieved from a PUBMED literature search on ‘time-lapse’ and ART.MAIN RESULTS AND THE ROLE OF CHANCE: A clear clinical benefit of the use of TLT, i.e. an increase in IVF success rates, remains to be proven. Meanwhile, TLT systems are being introduced in IVF laboratories. The working group listed 11 recommendations on what to do before introducing TLT in the lab. These statements include an assessment of the pros and cons of acquiring a TLT system, selection of relevant morphokinetic parameters, selection of an appropriate TLT system with technical and customer support, development of an internal checklist and education of staff. All these aspects are explained further here, based on the current literature and expert opinion.LIMITATIONS, REASONS FOR CAUTION: Owing to the limited evidence available, recommendations are mostly based on clinical and technical expertise. The paper provides technical advice, but leaves any decision on whether or not to use TLT to the individual centres.WIDER IMPLICATIONS OF THE FINDINGS: This document is expected to have a significant impact on future developments of clinical embryology, considering the increasing role and impact of TLT

XIST dampens X chromosome activity in a SPEN-dependent manner during early human development

XIST (X-inactive specific transcript) long noncoding RNA (lncRNA) is responsible for X chromosome inactivation (XCI) in placental mammals, yet it accumulates on both X chromosomes in human female preimplantation embryos without triggering X chromosome silencing. The XACT (X-active coating transcript) lncRNA coaccumulates with XIST on active X chromosomes and may antagonize XIST function. Here, we used human embryonic stem cells in a naive state of pluripotency to assess the function of XIST and XACT in shaping the X chromosome chromatin and transcriptional landscapes during preimplantation development. We show that XIST triggers the deposition of polycomb-mediated repressive histone modifications and dampens the transcription of most X-linked genes in a SPEN-dependent manner, while XACT deficiency does not significantly affect XIST activity or X-linked gene expression. Our study demonstrates that XIST is functional before XCI, confirms the existence of a transient process of X chromosome dosage compensation and reveals that XCI and dampening rely on the same set of factors.</p

Follicle Stimulating Hormone and Anti-Müllerian Hormone per Oocyte in Predicting in vitro Fertilization Pregnancy in High Responders: A Cohort Study

Background: Follicle stimulating hormone (FSH) and Anti-Müllerian hormone (AMH) are utilized to differentiate between good and poor response to controlled ovarian hyperstimulation. Their respective roles in defining functional ovarian reserve remain, however, to be elucidated. To better understand those we investigated AMH and FSH per oocyte retrieved (AMHo and FSHo). Methodology/Principal Findings: Three-hundred and ninety-six women, undergoing first in vitro fertilization cycles, were retrospectively evaluated. Women with oocyte yields.75 th percentile for their age group were identified as high responders. In a series of logistic regression analyses, AMHo and FSHo levels were then evaluated as predictive factors for pregnancy potential in high responders. Patients presented with a mean age of 38.065.0 years, mean baseline FSH of 11.868.7 mIU/mL and mean AMH of 1.662.1 ng/mL. Those 88 women, who qualified as high responders, showed mean FSH of 9.766.5 mIU/mL, AMH of 3.163.1 ng/mL and oocyte yields of 15.867.1. Baseline FSH and AMH did not predict pregnancy in high responders. However, a statistically significant association between FSHo and pregnancy was observed in high responders, both after univariate regression (p = 0.02) and when adjusted for age, percentage of usable embryos, and number of embryos transferred (p = 0.03). Rate of useable embryos also significantly affected pregnancy outcome independently of FSHo (p = 0.01). AMHo was also associated with clinical pregnancy chances in high responders (p = 0.03