A single fiber view of the nucleosome organization in eukaryotic chromatin.

Eukaryotic cells are thought to arrange nucleosomes into extended arrays with evenly spaced nucleosomes phased at genomic landmarks. Here we tested to what extent this stereotypic organization describes the nucleosome organization in Saccharomyces cerevisiae using Fiber-Seq, a long-read sequencing technique that maps entire nucleosome arrays on individual chromatin fibers in a high throughput manner. With each fiber coming from a different cell, Fiber-Seq uncovers cell-to-cell heterogeneity. The long reads reveal the nucleosome architecture even over repetitive DNA such as the ribosomal DNA repeats. The absolute nucleosome occupancy, a parameter that is difficult to obtain with conventional sequencing approaches, is a direct readout of Fiber-Seq. We document substantial deviations from the stereotypical nucleosome organization with unexpectedly long linker DNAs between nucleosomes, gene bodies missing entire nucleosomes, cell-to-cell heterogeneity in nucleosome occupancy, heterogeneous phasing of arrays and irregular nucleosome spacing. Nucleosome array structures are indistinguishable throughout the gene body and with respect to the direction of transcription arguing against transcription promoting array formation. Acute nucleosome depletion destroyed most of the array organization indicating that nucleosome remodelers cannot efficiently pack nucleosomes under those conditions. Given that nucleosomes are cis-regulatory elements, the cell-to-cell heterogeneity uncovered by Fiber-Seq provides much needed information to understand chromatin structure and function.

Ibuprofen delays ovulation by several hours: prospective controlled study in natural cycles with HCG-triggered ovulation.

RESEARCH QUESTION: Does ibuprofen, a non-steroidal anti-inflammatory drug (NSAID), delay ovulation? DESIGN: Two-stage, proof-of-concept, controlled study, assessing the percentage of non-ovulated follicles 42 h after HCG injection in patients taking ibuprofen. The intervention group consisted of women undergoing natural cycle IVF treatment taking ibuprofen 3 × 400 mg per day. The control group consisted of women undergoing timed sexual intercourse or intrauterine insemination. The proportion of patients with non-ovulated follicles in the ibuprofen group was first compared against a reference of 50% using a one-sample binomial test, and second against the proportion observed in the control group using an adjusted logistic regression. RESULTS: A total of 26 women were recruited in the ibuprofen intervention group. Twenty-five patients were recruited in the control group. The proportion of patients with delayed ovulation observed (22/26 [84.6%]; 95% CI 65.1% to 95.6%) was significantly higher than the reference of 50% (P < 0.001). In the control group, the proportion of patients with delayed ovulation was 20.0% ([5/25], 95% CI 6.8% to 40.7%). Compared with the ibuprofen group, a significantly increased probability of a delayed ovulation was found in the ibuprofen intervention group (adjusted OR 22.72, 95% CI 5.77 to 115; P < 0.001). Of the 22 women with delayed ovulation, oocytes were retrieved in 20 women (90.9%) and all oocytes were mature (metaphase II). CONCLUSIONS: Women trying to conceive should avoid non-selective NSAIDs around the time of ovulation. Ibuprofen or other NSAID can be used to delay ovulation for several hours in assisted reproductive technology and other infertility treatments if required.

Time-efficient consultation hours in the department of gynecological endocrinology.

BACKGROUND: The aim was to conduct a benchmark pilot study to find the best practice for consultation hours in the field of gynecological endocrinology. Suitable benchmarking participants were found in China, Germany, Greece, and Switzerland. Specifically, the study aimed to find the most time-efficient and beneficial consultation type in gynecological endocrinology focused on menopause and whether a shorter face-to-face consultation correlates with lower patient satisfaction. METHODS: This was an observational study. To analyze the processes of all benchmarking participants three tools were used: a measurement of time needed for the different consultation types, a questionnaire for patients and one for physicians. The primary endpoint was the time measurement of first consultations. Secondary endpoints were the time measurements of follow-up consultations and phone consultations and patient satisfaction. RESULTS: The mean overall duration of a first consultation differed from 20.4 min to 39.7 min (p = 0.003), mainly based on differences of the mean time to acquire the patient history, 5.6 to 21.6 min (p < 0.001). The percentage of patients who felt they had enough time to discuss questions ranged from 70% to 100% (p < 0.001). The percentage of patients who felt fully understood by their physician ranged from 62.5% to 92% (p = 0.006). The duration of a first consultation did not correlate with patients feeling well consulted (r=-0.048, p = 0.557). CONCLUSIONS: A concise patient history that concentrates on the most relevant points can reduce the total consultation time. Reducing consultation time can be made without compromising how well patients feel consulted.

The influence of Black Cohosh on hippocampal and hypothalamic gene expression profiles in ovariectomized rats and its potential to treat menopausal decrease in smell discrimination.

PURPOSE: Menopause is associated with a decrease in smell discrimination ability. This study assessed the impact of black cohosh on hippocampal (HC) and hypothalamic (HT) gene expression profiles in rats, to understand, if herbal treatment has an impact on neurologic changes due to menopause and whether this could address a decrease in smell discrimination. METHODS: HC and HT tissues from female Sprague Dawley rats (total n = 19) were analyzed at three different life stages: intact tissues of the HC (n = 4) and the HT (n = 4), oophorectomized tissues 3 months after oophorectomy (OVX) of the HC (n = 4) and the HT (n = 3), and tissues after treatment with an isopropanolic extract (iCR) from the rhizomes of black cohosh (60 mg/kg) for 3 months after OVX of the HC (n = 2) and the HT (n = 2). MAIN OUTCOME MEASURES: To reveal underlying biological processes a gene set enrichment analysis (GSEA) was performed. RESULTS: The GSEA revealed gene ontology terms that were significantly enriched, including several genes associated with the olfactory system, indicating biological processes regulated by treatment with iCR. Six olfactory receptor genes were further analyzed by another GSEA, demonstrating the possibility of iCR treatment to compensate for oophorectomy-induced changes. CONCLUSION: Findings suggest that herbal treatment, such as iCR, has an esteeming impact on HC and HT genes that are changed through menopause. Further studies are needed to suggest black cohosh as a treatment option for decreased smell discrimination.

Drifting codes within a stable coding scheme for working memory.

Working memory (WM) is important to maintain information over short time periods to provide some stability in a constantly changing environment. However, brain activity is inherently dynamic, raising a challenge for maintaining stable mental states. To investigate the relationship between WM stability and neural dynamics, we used electroencephalography to measure the neural response to impulse stimuli during a WM delay. Multivariate pattern analysis revealed representations were both stable and dynamic: there was a clear difference in neural states between time-specific impulse responses, reflecting dynamic changes, yet the coding scheme for memorised orientations was stable. This suggests that a stable subcomponent in WM enables stable maintenance within a dynamic system. A stable coding scheme simplifies readout for WM-guided behaviour, whereas the low-dimensional dynamic component could provide additional temporal information. Despite having a stable subspace, WM is clearly not perfect-memory performance still degrades over time. Indeed, we find that even within the stable coding scheme, memories drift during maintenance. When averaged across trials, such drift contributes to the width of the error distribution.

Oocyte maturity, oocyte fertilization and cleavage-stage embryo morphology are better in natural compared with high-dose gonadotrophin stimulated IVF cycles.

RESEARCH QUESTION: Does high-dose gonadotrophin stimulation have an effect on oocyte and early-stage embryo development? DESIGN: This was a retrospective study including 616 natural cycle IVF (NC-IVF) and 167 conventional IVF (cIVF) cycles. In total, 2110 oocytes were retrieved and analysed in fresh cycles. In NC-IVF, only human chorionic gonadotrophin was applied to trigger ovulation. In cIVF, antagonist protocols with daily 150-300 IU of human menopausal gonadotrophins were performed. The effect of gonadotrophins on oocyte and early-stage embryo development was analysed. Primary outcomes were the occurrence of mature (metaphase II) oocytes, zygotes and embryos with good morphology at the cleavage stage 2 days after oocyte retrieval. RESULTS: The mature oocyte rate (number of mature oocytes/number of retrieved oocytes) was higher in NC-IVF than cIVF cycles (89% versus 82%, adjusted odds ratio [aOR] 1.79, P = 0.001), as was the zygote rate per oocyte retrieved (70% versus 58%, aOR 1.76, P = 0.001) and the zygote rate per mature oocyte (79% versus 71%, aOR 1.62, P = 0.001). The percentage of zygotes that developed into cleavage-stage embryos was no different. For the transferred embryos, the probability of having a good embryo morphology with four blastomeres and a fragmentation of <10% (score 0) in cleavage-stage embryos was found to be higher in NC-IVF (proportional aOR for four blastomeres 2.00, P < 0.001; aOR 1.87 for a fragmentation score of 0, P = 0.003). CONCLUSIONS: Oocyte maturity, oocyte fertilization and morphology of the cleavage-stage embryo are affected by high-dose gonadotrophin stimulation in fresh IVF cycles.

Hormone replacement cycles are associated with a higher risk of hypertensive disorders: Retrospective cohort study in singleton and twin pregnancies.

OBJECTIVE: To elaborate the associations of different cycle regimens (natural cycle [NC], stimulated cycle [SC], hormone replacement cycle [HRC]) on maternal and neonatal adverse pregnancy outcomes after frozen-thawed embryo transfers (FET). DESIGN: Population-based registry study. SETTING: Swiss IVF Registry. POPULATION OR SAMPLE: Singleton (n = 4636) and twin (n = 544) live births after NC-FET (n = 776), SC-FET (n = 758) or HRC-FET (n = 3646) registered from 2014 to 2019. METHODS: Fifteen pregnancy pathologies were modelled for singleton and twin pregnancies using mixed models adjusted for cycle regimen, delivery, fertilisation technique, chronic anovulation, age of mother and centre. MAIN OUTCOME MEASURES: Maternal (vaginal bleeding, isolated arterial hypertension and pre-eclampsia) and neonatal (gestational age, birthweight, mode of delivery) adverse pregnancy outcomes. RESULTS: In singleton pregnancies, the incidences of bleeding in first trimester, isolated hypertension and pre-eclampsia were highest in HRC-FET with doubled odds of bleeding in first trimester (adjusted odds ratio [aOR] 2.23; 95% CI 1.33-3.75), isolated hypertension (aOR 2.50; 95% CI 1.02-6.12) and pre-eclampsia (aOR 2.16; 95% CI 1.13-4.12) in HRC-FET vs. NC-FET and with doubled respectively sixfold odds of bleeding (aOR 2.08; 95% CI 1.03-4.21) and pre-eclampsia (6.02; 95% CI 1.38-26.24) in HRC-FET versus SC-FET. In twin pregnancies, the incidence of pre-eclampsia was highest in HRC-FET with numerically higher odds of pre-eclampsia in HRC-FET versus NC-FET and versus SC-FET. CONCLUSIONS: Our data implied the highest maternal risks of hypertensive disorders in HRC-FET, therefore clinicians should prefer SC-FET or NC-FET if medically possible.

Purification and concentration of infectious koi herpesvirus using steric exclusion chromatography.

Koi herpesvirus (KHV) is the causative agent of a koi herpesvirus disease (KHVD) inducing high mortality rates in common carp and koi (Cyprinus carpio). No widespread effective vaccination strategy has been implemented yet, which is partly due to side effects of the immunized fish. In this study, we present an evaluation of the purification of infectious KHV from host cell protein and DNA, using the steric exclusion chromatography. The method is related to conventional polyethylene glycol (PEG) precipitation implemented in a chromatographic set-up and has been applied for infectious virus particle purification with high recoveries and impurity removal. Here, we achieved a yield of up to 55% of infectious KHV by using 12% PEG (molecular weight of 6 kDa) at pH 7.0. The recoveries were higher when using chromatographic cellulose membranes with 3-5 µm pores in diameter instead of 1 µm. The losses were assumed to originate from dense KHV precipitates retained on the membranes. Additionally, the use of >0.6 M NaCl was shown to inactivate infectious KHV. In summary, we propose a first step towards a purification procedure for infectious KHV with a possible implementation in fish vaccine manufacturing.

Low-dose clomiphene citrate does not reduce implantation and live birth rates in otherwise unstimulated modified natural cycle IVF-retrospective cohort study.

RESEARCH QUESTION: Does antioestrogen effect of clomiphene citrate (CC) on the endometrium reduce implantation and thereby decrease pregnancy and live birth rate per transferred embryo? METHODS: In this cohort, unstimulated IVF cycles modified with clomiphene citrate (CC-NC-IVF) and unstimulated, natural IVF cycles (NC-IVF) conducted between 2011 and 2016 were included. CC was applied in a dosage of 25mcg per day, starting on cycle day 7 until ovulation trigger day. Primary outcomes were clinical pregnancy rate, defined as amniotic sac visible in ultrasound, and live birth rate per transferred embryo. Miscarriage rate calculated as amniotic sac not ending in a live birth was secondary outcome. A modified mixed-effect Poisson regression model was applied, and adjustments were made for female age, parity, type and cause of infertility. Additionally, stratification by parity and age was performed. RESULTS: Four hundred and ninety-nine couples underwent a total of 1042 IVF cycles, 453 being NC-IVF and 589 being CC-NC-IVF cycles. Baseline characteristics of both groups did not differ. Addition of CC did neither decrease clinical pregnancy rate (aRR 0.86; 95% CI 0.67-1.12) nor live birth rate per transferred embryo (aRR 0.84; 95% CI 0.62-1.13) in comparison with NC-IVF. Miscarriage rate did not differ between CC-NC-IVF and NC-IVF (aRR 0.95; 95% CI 0.57-1.57). CONCLUSION: Low-dose CC does not reduce pregnancy or live birth rate per transferred embryo. It can be used in infertility treatment without negatively affecting the endometrium and implantation.

Absolute nucleosome occupancy map for the Saccharomyces cerevisiae genome.

Mapping of nucleosomes, the basic DNA packaging unit in eukaryotes, is fundamental for understanding genome regulation because nucleosomes modulate DNA access by their positioning along the genome. A cell-population nucleosome map requires two observables: nucleosome positions along the DNA ("Where?") and nucleosome occupancies across the population ("In how many cells?"). All available genome-wide nucleosome mapping techniques are yield methods because they score either nucleosomal (e.g., MNase-seq, chemical cleavage-seq) or nonnucleosomal (e.g., ATAC-seq) DNA but lose track of the total DNA population for each genomic region. Therefore, they only provide nucleosome positions and maybe compare relative occupancies between positions, but cannot measure absolute nucleosome occupancy, which is the fraction of all DNA molecules occupied at a given position and time by a nucleosome. Here, we established two orthogonal and thereby cross-validating approaches to measure absolute nucleosome occupancy across the Saccharomyces cerevisiae genome via restriction enzymes and DNA methyltransferases. The resulting high-resolution (9-bp) map shows uniform absolute occupancies. Most nucleosome positions are occupied in most cells: 97% of all nucleosomes called by chemical cleavage-seq have a mean absolute occupancy of 90 ± 6% (±SD). Depending on nucleosome position calling procedures, there are 57,000 to 60,000 nucleosomes per yeast cell. The few low absolute occupancy nucleosomes do not correlate with highly transcribed gene bodies, but correlate with increased presence of the nucleosome-evicting chromatin structure remodeling (RSC) complex, and are enriched upstream of highly transcribed or regulated genes. Our work provides a quantitative method and reference frame in absolute terms for future chromatin studies.

Gonadotrophin stimulation reduces follicular fluid hormone concentrations and disrupts their quantitative association with cumulus cell mRNA.

RESEARCH QUESTION: Do follicular fluid hormone concentrations and the mRNA expression of LHCG, FSH and androgen receptors, aromatase and anti-Müllerian hormone (AMH) in cumulus granulosa cells differ in naturally matured and stimulated follicles? DESIGN: Cross-sectional study involving 57 natural cycle IVF (NC-IVF) and 36 conventional gonadotrophin-stimulated IVF (cIVF) cycles performed between 2014 and 2016. cIVF was performed by ovarian stimulation with human menopausal gonadotrophin and gonadotrophin-releasing hormone antagonists. Hormone concentrations were determined in the follicular fluid of the leading follicle, and mRNA concentrations were quantified by reverse transcription polymerase chain reaction in RNA extracted from granulosa cells of the cumulus oophorus complex obtained from these fluids. RESULTS: Follicular fluid hormone concentrations were significantly lower in cIVF compared with NC-IVF follicles. Median concentrations were 0.50 and 14.5 mIU/ml for LH (P < 0.001), 16.1 and 46.5 nmol/l for testosterone (P < 0.001), 1270 and 2675 nmol/l for oestradiol (P < 0.001), and 12.3 and 28.9 pmol/l for AMH (P < 0.001), respectively. In cumulus granulosa cells, mRNA concentrations for LH receptor, FSH receptor, androgen receptor, aromatase and AMH did not differ between cIVF and NC-IVF follicles. Several hormone and mRNA concentrations were quantitatively associated in natural cycles such as follicular fluid AMH and cumulus granulosa cells AMH RNA (r2 = 0.107, P = 0.013), follicular fluid testosterone and cumulus granulosa cell AMH RNA (r2 = 0.158, P = 0.002), follicular fluid oestradiol and cumulus granulosa cell AMH RNA (r2 = 0.105, P = 0.014) and follicular fluid oestradiol and aromatase (r2 = 0.113, P = 0.011). In contrast, these associations were not observed in stimulated cycles. CONCLUSION: These findings indicate some effects of gonadotrophin stimulation on follicular physiology, which could be a cause for the previously suggested lower oocyte quality in cIVF compared with NC-IVF.

Perinatal outcomes in singletons after fresh IVF/ICSI: results of two cohorts and the birth registry.

RESEARCH QUESTION: How are perinatal outcomes of live-born singletons after stimulated and unstimulated IVF different from perinatal outcomes in (i) children born in a tertiary centre and (ii) all children born in Switzerland? METHODS: This cohort study compared the perinatal outcomes of two birth cohorts and the national live birth registry. Relative risks were calculated using modified Poisson regression and clustering for siblings and adjustment for maternal age, parity and childs sex. RESULTS: Of the 636,639 live births, 311 were in the Bern IVF Cohort (144 stimulated, 167 unstimulated), 2332 in the tertiary centre and 633,996 in the Swiss Live Birth Registry (SLBR). Perinatal outcomes following IVF did not differ compared with births in the SLBR (adjusted relative risk [aRR]; 95% confidence interval [CI]), with the exception of the increased risk of small for gestational age (1.31; 1.01 to 1.70, P = 0.04; aRR 1.12; 0.87 to 1.45, P = 0.39). Children born following stimulated IVF had a higher risk of low birthweight (2.17; 1.27 to 3.69, P < 0.01; aRR 1.72; 1.01 to 2.93, P = 0.05), and of being small for gestational age (1.50; 1.05 to 2.14, P = 0.03; aRR 1.31; 0.92 to 1.87; P = 0.13), whereas children born after unstimulated IVF had no increased risks compared with the SLBR. Higher Caesarean rate after IVF was mainly associated with higher maternal age. CONCLUSION: Singletons in the Bern IVF Cohort do not show less favourable perinatal outcomes. Gonadotrophin stimulation seems to have an effect, because lower risks were associated with unstimulated IVF.

The case for mild stimulation for IVF: recommendations from The International Society for Mild Approaches in Assisted Reproduction.

The practice of ovarian stimulation for IVF is undergoing a fundamental re-evaluation as recent data begin to successfully challenge the traditional paradigm that ovarian stimulation should be aimed at the retrieval of as many oocytes as possible, in the belief that this will increase pregnancy rates. An opposing view is that live birth rate should not be the only end-point in evaluating the success of IVF treatment and that equal emphasis should be placed on safety and affordability. The International Society for Mild Approaches in Assisted Reproduction (ISMAAR) committee has carried out an up-to-date literature search, with the evidence being graded according to the University of Oxford's Centre for Evidence-Based Medicine. The recommendations were formulated taking into account the quality of evidence on the efficacy, risk and cost of each intervention. ISMAAR recommends adopting a mild approach to ovarian stimulation in all clinical settings as an increasing body of evidence suggests that mild stimulation is as effective as conventional stimulation, while being safer and less expensive. Mild ovarian stimulation could replace conventional stimulation, thus making IVF safer and more accessible worldwide.

Awareness of non-communicable diseases in women: a cross-sectional study.

Chronic non-communicable diseases (NCD) are the major reason for death, morbidity, loss of independency and public health cost. NCD prevalence could be significantly reduced by adopting a healthy lifestyle. This cross-sectional cohort study (online survey) in 221 women aimed to assess NCD awareness, knowledge about NCD prevention and willingness to adopt a healthier lifestyle in women. Overall, NCD awareness level was quite high with, however, information mainly originating from lay media, probably being one reason for false estimations of age groups mainly affected by NCD, impact of NCD on quality of life, NCD mortalities, and the extent of NCD prevention by lifestyle interventions, respectively. Furthermore, also due to mainly lay media, half of women knew online NCD risk calculators, most of them would like to know their NCD risk, but only few had been offered NCD risk calculation by their physician. The mean threshold for willing to adopt a healthier lifestyle was a roughly calculated 37% 5-10 years risk to develop a certain NCD. Acceptance of non-pharmacological interventions for NCD prevention was high, however, major barriers for not implementing a healthier lifestyle were lack of expert information and lack of time. In conclusion, future public health strategies should focus on distributing better understandable and correct information about NCD as well as meeting the individuals' request for personalized NCD risk calculation. Furthermore, physicians should be better trained for personalized NCD prevention counseling.

Impact of chronic stress exposure on cognitive performance incorporating the active and healthy aging (AHA) concept within the cross-sectional Bern Cohort Study 2014 (BeCS-14).

PURPOSE: This study aims to verify that the mental-cognitive domain of the validated generic bio-functional status (BFS)/bio-functional age (BFA) assessment tool, incorporating the concept of Active and Healthy Ageing (AHA), reflects cognitive performance. In addition, the effects of chronic stress exposure on the mental-cognitive BFS/BFA should be investigated. METHODS: The study was carried out as a monocenter, cross-sectional, observational, non-interventional trial (Bern Cohort Study 2014, BeCS-14) with the participation of 147 non-pediatric, non-geriatric subjects. All participants followed a standardized battery of biopsychosocial assessments consisting of BFS/BFA, a validated cognitive performance test battery (Inventar zur Gedächtnisdiagnostik; IGD) and a validated questionnaire for the assessment of chronic stress (Trier Inventory for the assessment of Chronic Stress; TICS), respectively. RESULTS: Mean cognitive performance was average and higher in younger or better educated individuals. The BFA of the participants was 7.8 ± 7.8 year-equivalents below their chronological age. The mental-cognitive BFS/BFA assessment correlated well with the validated questionnaire for cognition assessment, the IGD. Further, three TICS subdomains (work overload (r = - 0.246, p = 0.003), work discontent (r = - 0.299, p = 0.006) and pressure to succeed (r = - 0.274, p < 0.001)), reflecting mainly work-related stress, showed a significant negative correlation with the mental-cognitive BFS/BFA. CONCLUSIONS: Our study shows that the BFS/BFA assessment tool follows European Innovation Partnership on Active and Healthy Ageing (EIP-AHA) requirements. Further, we could demonstrate that higher levels of chronic work-related stress may be associated with poorer mental-cognitive performance and a pro-aging state indicating that cognitive impairments can be reduced by stress management interventions.

Unimodal and Bimodal Access to Sensory Working Memories by Auditory and Visual Impulses.

It is unclear to what extent sensory processing areas are involved in the maintenance of sensory information in working memory (WM). Previous studies have thus far relied on finding neural activity in the corresponding sensory cortices, neglecting potential activity-silent mechanisms, such as connectivity-dependent encoding. It has recently been found that visual stimulation during visual WM maintenance reveals WM-dependent changes through a bottom-up neural response. Here, we test whether this impulse response is uniquely visual and sensory-specific. Human participants (both sexes) completed visual and auditory WM tasks while electroencephalography was recorded. During the maintenance period, the WM network was perturbed serially with fixed and task-neutral auditory and visual stimuli. We show that a neutral auditory impulse-stimulus presented during the maintenance of a pure tone resulted in a WM-dependent neural response, providing evidence for the auditory counterpart to the visual WM findings reported previously. Interestingly, visual stimulation also resulted in an auditory WM-dependent impulse response, implicating the visual cortex in the maintenance of auditory information, either directly or indirectly, as a pathway to the neural auditory WM representations elsewhere. In contrast, during visual WM maintenance, only the impulse response to visual stimulation was content-specific, suggesting that visual information is maintained in a sensory-specific neural network, separated from auditory processing areas.SIGNIFICANCE STATEMENT Working memory is a crucial component of intelligent, adaptive behavior. Our understanding of the neural mechanisms that support it has recently shifted: rather than being dependent on an unbroken chain of neural activity, working memory may rely on transient changes in neuronal connectivity, which can be maintained efficiently in activity-silent brain states. Previous work using a visual impulse stimulus to perturb the memory network has implicated such silent states in the retention of line orientations in visual working memory. Here, we show that auditory working memory similarly retains auditory information. We also observed a sensory-specific impulse response in visual working memory, while auditory memory responded bimodally to both visual and auditory impulses, possibly reflecting visual dominance of working memory.

The endocrine milieu in naturally matured follicles is different in women with high serum anti-Müllerian hormone concentrations.

RESEARCH QUESTION: Is the endocrine milieu different in women with low serum anti-Müllerian hormone (AMH) concentration compared with women with high concentration? DESIGN: Cohort study of 84 women (four groups) classified according to AMH concentration and age undergoing natural cycle IVF treatment. Concentrations of LH, oestradiol, testosterone, androstenedione and AMH were determined in follicular fluid (FF), associations analysed and clinical outcome parameters evaluated. RESULTS: A positive correlation between serum and FF AMH concentrations was confirmed. Follicular fluid androstenedione concentration was positively correlated with serum AMH concentration (P < 0.0001, r2 = 0.197). The correlation between FF LH and FF testosterone concentration in all women was not significant (P = 0.050, r2 = 0.046); however, the correlation between FF androstenedione in women with high serum AMH concentration was significant (P = 0.032, r2 = 0.220). Follicular fluid testosterone and androstenedione were positively correlated with FF oestradiol overall and in some individual groups. The high serum AMH concentration group showed the highest FF AMH and androstenedione concentrations and lowest oestradiol-testosterone and oestradiol-androstenedione ratios. High FF AMH concentration was associated with a higher clinical pregnancy rate and high FF oestradiol concentration with a slightly better embryo quality. CONCLUSIONS: Differences in the endocrine milieu in women with high serum AMH concentration seem to be caused by increased follicular LH concentration. In women with high serum AMH concentration, FF androstenedione is increased and ratios of oestradiol-testosterone and oestradiol-androstenedione are decreased, suggesting a disturbed endocrine milieu caused by reduced metabolization of FF androgens into oestrogens. In natural cycles, FF AMH concentrations are positively associated with higher clinical pregnancy rates and oestradiol concentrations with a higher embryo score.

Breastfeeding following in vitro fertilisation in Switzerland-Does mode of conception affect breastfeeding behaviour?

AIM: Breastfeeding has numerous advantages. Our aim was to investigate whether breastfeeding initiation and duration in women with pregnancies conceived through in vitro fertilisation differ from spontaneously conceived pregnancies. METHODS: This is a comparative cross-sectional study about breastfeeding behaviour performed at the Bern University Hospital including mothers of singletons conceived by in vitro fertilisation (n = 198) with or without gonadotropin stimulation between 2010 and 2016 (in vitro fertilisation group). They were compared to a population-based control group (n = 1421) of a randomly selected sample of mothers in Switzerland who delivered in 2014. RESULTS: A total of 1619 women were included in this analysis. Breastfeeding initiation rates were high, similar between the in vitro fertilisation group (93.4%) and the control group (94.8%). No increased risk of stopping breastfeeding earlier after in vitro fertilisation treatment compared to the control group could be found over the observational period of 12 months (HR = 1.00, 95% CI 0.83-1.20, P = .984). There was no difference in breastfeeding initiation or duration after gonadotropin-stimulated vs unstimulated in vitro fertilisation. CONCLUSION: In Switzerland, in vitro fertilisation treatments were not associated with earlier breastfeeding cessation. This result is reassuring for mothers undergoing in vitro fertilisation.

Regulation and adaptation of endocrine axes at high altitude.

As a model of extreme conditions, eight healthy women, part of a 40-member Nepal mountain-climbing expedition, were monitored for dynamic endocrine adaptations. Endocrine measurements were made at frequent intervals over a 6-10-h period at four altitudes: 450 m, 4,800 m (base camp), 6,050 m, and again at 4,800 m (on descent) after an acclimatization (A) period (4,800 mA). Quantified hormones were growth hormone (GH), prolactin (PROL), cortisol (Cort), thyroid-stimulating hormone (TSH), and free thyroxine. These hormones are important to the anabolic/catabolic balance of the body, and are vital to growth, homeostasis, hypothalamic inhibition, regulation of stress, and metabolism. A key secondary question was the degree to which acclimatization can stabilize hormonal disruption. On the basis of statistical false discovery rates, the present analyses unveil marked adaptive changes in the thyroid axis at the level of pulsatile secretion of the pituitary hormone TSH and its downstream product, free thyroxine; strong effects on the mass of GH, TSH, Cort, and PROL secretion per burst; and prominent pulsatile frequency disruption and recovery for PROL and Cort. Because pulsatility changes reflect de facto perturbations in hypothalamo-pituitary control mechanisms, the present data introduce the concept of both frequency- and amplitude-dependent adaptive control of brain-pituitary neuroendocrine signals under conditions of extreme altitude exertion and exposure.

The indication for fertility preservation in women with Turner syndrome should not only be based on the ovarian reserve but also on the genotype and expected future health status.

Fertility preservation in women with Turner syndrome is highly controversial. Some strongly recommend freezing of ovarian tissue at a young age, others do not. The controversy is partly due to different perspectives and professions. Biologists prefer to freeze young ovaries with high follicle density, reproductive physicians want to avoid risky operations and iatrogenic infertility by removing one ovary, and cardiologists and obstetricians warn against the risks of later pregnancies. Accordingly, fertility preservation in young women with Turner syndrome is more than just the freezing of ovarian tissue or oocytes. Fertility preservation requires a balanced decision considering the conservation of fertility, the protection of reproductive health, and future health consequences. Therefore, fertility preservation strategies should be based not only on the individual ovarian reserve but also on the genotype and the expected cardiac health status to decide what is the best option: to freeze tissue or alternatively to wait and see.