Pro-inflammatory interactions of streptolysin O toxin with human neutrophils in vitro

The recent global resurgence of severe infections caused by the Group A streptococcus (GAS) pathogen, Streptococcus pyogenes, has focused attention on this microbial pathogen, which produces an array of virulence factors, such as the pore-forming toxin, streptolysin O (SOT). Importantly, the interactions of SOT with human neutrophils (PMN), are not well understood. The current study was designed to investigate the effects of pretreatment of isolated human PMN with purified SOT on several pro-inflammatory activities, including generation of reactive oxygen species (ROS), degranulation (elastase release), influx of extracellular calcium (Ca2+) and release of extracellular DNA (NETosis), using chemiluminescence, spectrophotometric and fluorimetric procedures, respectively. Exposure of PMN to SOT alone caused modest production of ROS and elastase release, while pretreatment with the toxin caused significant augmentation of chemoattractant (fMLP)-activated ROS generation and release of elastase by activated PMN. These effects of treatment of PMN with SOT were associated with both a marked and sustained elevation of cytosolic Ca2+concentrations and significant increases in the concentrations of extracellular DNA, indicative of NETosis. The current study has identified a potential role for SOT in augmenting the Ca2+-dependent pro-inflammatory interactions of PMN, which, if operative in a clinical setting, may contribute to hyper-activation of PMN and GAS-mediated tissue injury.

Management of syncope in the Emergency Department: a European prospective cohort study (SEED)

BACKGROUND AND IMPORTANCE

In 2018, the European Society of Cardiology (ESC) produced syncope guidelines that for the first-time incorporated Emergency Department (ED) management. However, very little is known about the characteristics and management of this patient group across Europe.

OBJECTIVES

To examine the prevalence, clinical presentation, assessment, investigation (ECG and laboratory testing), management and ESC and Canadian Syncope Risk Score (CSRS) categories of adult European ED patients presenting with transient loss of consciousness (TLOC, undifferentiated or suspected syncope).

DESIGN

Prospective, multicentre, observational cohort study.

SETTINGS AND PARTICIPANTS

Adults (≥18 years) presenting to European EDs with TLOC, either undifferentiated or thought to be of syncopal origin.

MAIN RESULTS

Between 00:01 Monday, September 12th to 23:59 Sunday 25 September 2022, 952 patients presenting to 41 EDs in 14 European countries were enrolled from 98 301 ED presentations (n = 40 sites). Mean age (SD) was 60.7 (21.7) years and 487 participants were male (51.2%). In total, 379 (39.8%) were admitted to hospital and 573 (60.2%) were discharged. 271 (28.5%) were admitted to an observation unit first with 143 (52.8%) of these being admitted from this. 717 (75.3%) participants were high-risk according to ESC guidelines (and not suitable for discharge from ED) and 235 (24.7%) were low risk. Admission rate increased with increasing ESC high-risk factors; 1 ESC high-risk factor; n = 259 (27.2%, admission rate=34.7%), 2; 189 (19.9%; 38.6%), 3; 106 (11.1%, 54.7%, 4; 62 (6.5%, 60.4%), 5; 48 (5.0%, 67.9%, 6+; 53 (5.6%, 67.9%). Furthermore, 660 (69.3%), 250 (26.3%), 34 (3.5%) and 8 (0.8%) participants had a low, medium, high, and very high CSRS respectively with respective admission rates of 31.4%, 56.0%, 76.5% and 75.0%. Admission rates (19.3-88.9%), use of an observation/decision unit (0-100%), and percentage high-risk (64.8-88.9%) varies widely between countries.

CONCLUSION

This European prospective cohort study reported a 1% prevalence of syncope in the ED. 4 in 10 patients are admitted to hospital although there is wide variation between country in syncope management. Three-quarters of patients have ESC high-risk characteristics with admission percentage rising with increasing ESC high-risk factors.

Intergenerational effects of ionizing radiation: review of recent studies from human data (2018-2021)

PURPOSE

The purpose of this paper was to conduct a review of the studies published between 2018 and 2022 to investigate radiation-related effects in the offspring of human individuals exposed to ionizing radiation.

METHODS

The search identified 807 publications, from which 9 studies were selected for detailed analysis to examine for effects in children whose parents were exposed to various types and doses of radiation.

RESULTS

The review does not yield substantial evidence supporting intergenerational effects of radiation exposure in humans. However, caution is required when interpreting the results due to limitations in the majority of the published articles.

CONCLUSION

This review, covering the period 2018-2022, serves as an extension of the previous systematic review conducted by Stephens et al. (2024), which encompassed the years 1988-2018. Together, these two papers offer a comprehensive overview of the available evidence regarding the intergenerational effects of parental pre-conceptional exposure to ionizing radiation. Overall, the findings do not provide strong evidence supporting a significant association between adverse (or other) outcomes in unexposed children and parental preconception radiation exposure.

Emerging markers of cancer cachexia and their relationship to sarcopenia

PURPOSE

Emerging biomarkers of cancer cachexia and their roles in sarcopenia and prognosis are poorly understood. Baseline assessments of anthropometrics, sarcopenia, cachexia status and biomarkers of cachexia were measured in patients with advanced cancer and healthy controls. Thereafter, relationships of the biomarkers with cachexia and sarcopenia were explored.

METHODS

A prospective case-control design was used, including 40 patients with advanced cancer and 40 gender, age-matched controls. Bioelectrical impedance [skeletal muscle index (SMI)] and hand dynamometry [hand grip strength (HGS)] assessed sarcopenia and a validated tool classified cancer cachexia. Albumin, lymphocyte and platelet counts, haemoglobin, C-reactive protein (CRP), pro-inflammatory cytokines/chemokines and citrullinated histone H3 (H3Cit) were measured.

RESULTS

Patients had significantly lower SMI (6.67 kg/m2 versus 7.67 kg/m2, p =  < 0.01) and HGS (24.42 kg versus 29.62 kg) compared to controls, with 43% being sarcopenic. Significant differences were found for albumin, lymphocyte and platelet counts, haemoglobin, CRP, and tumour necrosis factor α (TNFα), (p < 0.01). Interleukin (IL)-6 (p < 0.04), IL-8 (p = 0.02), neutrophil/lymphocyte ratio (NLR), p = 0.02, platelet/lymphocyte (PLR) ratio, p < 0.01 and systemic immune inflammatory index (SII), p < 0.01 differed significantly. No difference was observed for CXC motif chemokine ligand 5 [CXCL5 or epithelial neutrophil-activating peptide 78 (ENA78)] or H3Cit. Albumin and haemoglobin correlated negatively with total protein, skeletal muscle mass and SMI (all p < 0.01). The presence of sarcopenia associated significantly with albumin, haemoglobin and CRP.

CONCLUSION

Significant relationships and differences of haemoglobin, CRP and albumin supports future use of these biomarkers in cancer cachexia. CXCL5 and H3Cit as valuable biomarkers in cancer cachexia remains to be defined.

1354 USING REALIST PROGRAMME THEORY TO DESIGN A NEW INTERVENTION FOR IMPROVING RECOVERY AFTER DELIRIUM

Introduction

People who recover poorly after delirium are likely to require an increased level of care. It is presently unknown whether interventions to improve recovery after delirium are effective and cost-effective. This research aimed to develop a programme theory to inform the design of an intervention to improve recovery after delirium.

Method

A rapid realist review of literature was conducted to develop an initial programme theory. Following this, a qualitative investigation of the perceived rehabilitation needs of older people who have experienced delirium during a hospital stay was conducted via semi-structured interviews with 41 key stakeholders (older people (5), carers (12), and healthcare professionals (24)). Data were analysed using a realist approach to identify what works, for whom, and in what context. This was deductively informed by the initial programme theory while also employing an inductive analysis to identify novel insights. Through an iterative, retroductive process, context-mechanism-outcome configurations (CMOCs) were coded to reflect stakeholders’ views to refine the programme theory.

Results

The initial programme theory highlighted the importance of cognitive and physical rehabilitation and emotional support as key domains of recovery. New CMOCs included optimisation of good medical care to manage delirium and monitoring and management of underlying medical conditions to promote recovery. Others included developing educational resources and support networks for older people and their carers to aid sense-making, and encouraging social interaction to reduce isolation and empower independent functioning. These recovery elements should be addressed in a person-centred manner that is tailored to individual needs and preferences, engages carers, integrates intervention goals into daily functioning, and ensures continuity of care.

Conclusion

A refined programme theory was developed and is currently being used to design a manualised intervention to improve recovery after delirium. The acceptability of the intervention will be tested in a multi-centre, single-arm feasibility study.

O003 Radiation-related chromosomal aberrations observed in high volume endovascular operators performing X-ray guided surgery

Introduction

The biological effects of chronic, low dose radiation, to which operators performing fluoroscopy-guided procedures are exposed, are unknown. We have previously demonstrated acute DNA damage/repair in lymphocytes from operators performing fluoroscopy-guided endovascular aneurysm repair (EVAR), but these markers normalised after 24 hours and did not inform on the residual accumulated effects of chronic radiation exposure. In the present study cytogenetic techniques were used to examine for chromosomal aberrations in endovascular operators.

Methods

Peripheral blood lymphocytes were isolated from high volume endovascular operators performing EVAR and age-matched radiation naïve general surgeons as controls. Giemsa staining was used to visualise the full complement of chromosomes and all dicentrics, where 2 centromeres are present in a single chromosome, were identified. The genome was analysed for abnormal exchanges of genetic material between chromosomes using multiplex fluorescence in situ hybridisation (mFISH).

Results

Lymphocytes from 18 operators (12 exposed, 6 controls) were analysed. A higher frequency of dicentric chromosomes were found in exposed operators compared with controls (0.0011 vs 0.0004, respectively, P=0.002) after examining 54,000 lymphocytes. Twice as many complex chromosome rearrangements were seen in endovascular operators compared with controls (0.48% vs 0.24%). Aneuploidy, the abnormal loss of chromosomes, was more frequent in endovascular operators with a median difference of 0.35 per chromosome (P=0.004).

Conclusion

We have found a higher frequency of chromosomal aberrations in endovascular operators compared with radiation naïve colleagues. This justifies further individual biological profiling for genomic instability and personalised radiation risk assessment.

Take-home message

Radiation-related DNA damage occurs in endovascular operators despite current radiation protection measures. Biological dosimetry could be a useful tool, allowing personalised risk assessment.

P-422 A retrospective cohort study on the usefulness of Endometrial Receptivity Analysis (ERA) prior to a gestational carriers’ (GC) first euploid frozen embryo transfer (FET)

Study question

Does determination of endometrial receptivity by ERA improve the outcome of FET for GC prior to their first FET using a euploid embryo?

Summary answer

GC with ERA prior to FET had 92.3% implantation and 84.6% live birth rate (LBR) compared to 81.5% implantation rate and 72.2% LBR without ERA.

What is known already

The endometrial window of implantation is approximately 24 hours wide with a complex interaction of autocrine, paracrine and endocrine factors. Successful embryo implantation involves a 3-step process of apposition, adhesion and invasion of an embryo into a receptive endometrium. The ERA was developed using the expression profile of 248 genes using Next Generation Sequencing to determine if the endometrium is receptive, early receptive, late receptive, pre-receptive or post-receptive to objectively determine the optimal timing of progesterone exposure prior to embryo transfer. Some studies have shown statistically significant improvements in live birth rates while other studies have shown no difference.

Study design, size, duration

A retrospective cohort study compared the implantation and live birth rates of 26 GC who chose to have a personalized embryo transfer using their ERA profile vs. 54 GC who used our standard FET protocol without an ERA prior to their first euploid FET. All GC having their first FET from January 2018 – December 2020 were included.

Participants/materials, setting, methods

A single private practice fertility clinic performed 80 euploid FET cycles on first-time GC from January 2018 – December 2020. All intended parents were offered the opportunity to complete an ERA for their GC prior to their first FET cycle. Implantation and live birth rates were calculated for all FET cycles using a GC for the first time with associated p – values.

Main results and the role of chance

GC were 22 – 38 years old with a mean age of 30 and a history of 2.4 previous spontaneous births prior to their first FET. GC who used a standard FET protocol with 5 days of progesterone (P + 5) exposure before FET had an implantation rate of 81.5% and a live birth rate of 72.2%, compared to an implantation rate of 92.3% and a live birth rate of 84.6% for GC who used a personalized embryo transfer protocol based on their ERA profile (p = 0.17). 19.2% of GC had a receptive endometrial profile using P + 5, 26.9% of GC were pre-receptive needing P + 5.5 and 53.8% needed P + 6. No GC were found to have a post-receptive endometrial profile (P + 4 or P + 4.5). Our retrospective cohort study was not powered to find a statistically significant difference, though our data trended towards an improvement in both implantation and live birth rates by over 10% if a GC were to complete an ERA prior to her first FET.

Limitations, reasons for caution

Implantation and live birth rates for the clinic during the study period were 75% and 68% respectively using euploid embryos. Our high baseline implantation and live birth rates, coupled with low numbers of patients included in this study, may make these results less generalizable to the IVF population at large.

Wider implications of the findings

It is controversial to recommend an ERA to a good prognosis patient such as a GC without a prior unsuccessful euploid FET. These results should prompt further study to confirm our findings with a larger prospective randomized controlled trial of gestational carriers using ERA profiles prior to their first FET.

Trial registration number

N/A

P-458 Testosterone treatment induces changes in stromal collagen and elastin content of the ovaries of transgender men

Study question

Does gender-affirming testosterone therapy alter the composition of the extra-cellular matrix (ECM) within the ovarian stroma and subsequently affect follicle activation in vivo

Summary answer

Ovarian stroma of trans men is more collagenous and less elastic, indicating fibrotic change. This may affect in vivo follicle growth activation

What is known already

Changes in the ovarian stroma have been demonstrated in the ovaries of transgender men taking testosterone, including thickening of the tunica albuginea, stromal cell hyperplasia and stromal cell luteinisation. Ovaries of trans men also have increased cortical stiffness. These changes are similar to those seen in female patients with PCOS and in physiological ovarian aging, which has been attributed to accumulation of collagen in the ECM. Increasing stiffness of the supportive follicular microenvironment has been shown to reduce follicle growth activation in vitro

Study design, size, duration

Whole ovaries were obtained from transgender men (mean age 27.6 ± 1.7 years, n = 8) with informed consent at oophorectomy. All patients had received 1000mg testosterone undecanoate intramuscularly at 12-16 week intervals for a minimum of 18 months pre-operatively (range 18 months-10 years). Cortical tissue was dissected into small fragments (≈1x1x0.5mm) and fixed for histological and immunohistochemical analysis. Testosterone-treated ovaries were compared to cortical biopsies from age-matched healthy women obtained at caesarean section (mean age 31.8±1.5, n = 8).

Participants/materials, setting, methods

Follicle number, classification of developmental stage, non-growing follicle density (NGFD) and stromal cell density were evaluated by histological analysis of ovarian cortical tissue. Sections were stained with Picrosirius red (PSR) to analyse total collagen content using brightfield microscopy. Polarised light was also used to analyse the collagen birefringence, which allows quantification of collagen fibre thickness into thick, medium or thin. Total elastin content was evaluated using immunofluorescence.

Main results and the role of chance

4526 follicles were analysed. Transgender ovary showed a higher proportion of non-growing follicles found compared to control (93.9±1.2% vs 84.6±1.5% p &lt; 0.05): the proportions of primary (4.7±0.9% vs 10.6±1.5%, p = 0.2) and secondary (1.4±0.4% vs 4.6±0.7%, p = 0.1) follicles tended to be lower. Stromal cell density was significantly higher in transgender ovarian cortex than control (2.5±0.1 x106cells/mm3 vs 1.7±0.1 x106cells/mm3), indicating stromal cell hyperplasia. Combined data from control and transgender groups showed a positive correlation between NGFD and stromal density (r = 0.64, p = 0.01).

Transgender ovary had a higher total collagen content (77.2±1.2%) compared to control (31.3±3.3%, p &lt; 0.005). Analysis of collagen birefringence showed that transgender ovaries had similar quantities of thick collagen fibres (0.014±0.005 vs 0.010±0.009, p = 0.1), more medium thickness collagen fibres (45.1±6.6%vs 14.4±4.9%, p &lt; 0.05) and fewer thinner fibres (41.5±9.6% vs 27.7±2.8%, p = 0.08) than control. The total elastin content in transgender ovaries was lower than control (1.3±0.1% vs 3.6±0.6%, p &lt; 0.005) and subsequently, the collagen/elastin ratio was significantly higher (63.1±7.9 vs 10±1.3, p &lt; 0.005).

Limitations, reasons for caution

The impact of these findings on in vivo follicle growth are unclear. The effect of duration of testosterone treatment has not investigated.

Wider implications of the findings

More collagenous, less elastic ovarian stroma in trans men indicates fibrotic change; these findings are similar to women with PCOS and with reproductive ageing. These stromal changes may alter follicle growth activation and may contribute value to our understanding of the regulation of follicle function in a range of conditions.

Trial registration number

nil

P-698 Pituitary functioning gonadotroph adenomas (FGA)-induced ovarian hyperstimulation syndrome (OHSS): results from tertiary neuroendocrine centres in the UK

Study question

There are no published series of OHSS due to FGA. What FGA features should clinicians look for during OHSS, and what treatments are effective?

Summary answer

FGA tumour size is always &gt;10mm. Other pituitary hormones may be deficient. Surgical resection of FGA is an effective treatment for OHSS.

What is known already

Pituitary adenomas affect 1:1000 adults and are classified as functioning or non-functioning. Non-functioning pituitary adenomas do not secrete hormones, but most commonly stain histologically gonadotroph cells. Functional pituitary adenomas secrete hormones such as prolactin causing prolactinoma. However, it is rare for a pituitary tumour to cause clinical features of excessive gonadotrophins (functioning gonadotroph adenoma; FGA).

Single case reports, but no case series, have been published on the presentation of FGA-induced OHSS in women.

Surgical excision of adenomas has been reported to cause remission of symptoms, though systematic data are lacking owing to rarity of these tumours.

Study design, size, duration

National case series from tertiary neuroendocrine units in England, Wales and Scotland.

Participants/materials, setting, methods

Eight high-volume pituitary endocrine tertiary units within England, Wales and Scotland audited their records for any cases of FGA-induced OHSS; only seven patients have been identified to date. In all cases, there had been no recent exposure to assisted reproductive technologies (ART) or drugs known to induce OHSS including gonadotrophins or selective oestrogen receptor modulators (SERMS).

Main results and the role of chance

Seven cases of FGA were identified with mean age 31.6 years (range 16-48) at diagnosis. Two-of-seven women presented acutely unwell with abdominal pain, distention and palpable mass requiring oophorectomy for ovarian torsion/ruptured ovarian cyst. The remaining five women presented with abdominal pain (n = 2), thyrotoxicosis (n = 1), menstrual irregularities/galactorrhoea (n = 1) and visual disturbances (n = 1). All women experienced intermittent pelvic pain during medical attendance. Pelvic ultrasound demonstrated enlarged multiseptated ovaries (volume ranging 27-442cm3). Ascites was noted in one woman. Six women had visual field defects due to optic chiasm compression on formal assessment. Median FSH was 26.10 u/L (8.3-33), but LH was &lt;2.5 u/L in all cases. Estradiol (E2) far exceeded the reference range in 5/7 women (2990 to &gt; 18000pmol/L);E2 was at the upper limit of normal in the remaining 2/7 women (960-1450pmol/L). Hyperprolactinaemia, hyperthyroidism and other pituitary hormones deficiency were noted in 6/7, 1/7 and 4/7 women respectively. All FGAs were macroadenomas with diameters ranging 16-48mm. Two patients were administered a somatostatin analogue prior to surgery, but FSH, E2 and tumour size did not change. Transsphenoidal surgery was performed in 6/7 women, and always improved symptomatic and biochemical features of OHSS; however, residual FGA tumour was present post-operatively in all cases studied.

Limitations, reasons for caution

It is possible that some ‘non-functioning’ gonadotroph adenomas cause subclinical problems including menstrual irregularity and mild OHSS which were never diagnosed.

We have insufficient data to determine the prognosis for future pregnancy after FGA-induced OHSS.

This study utilised historical case-notes, so some data is missing.

Wider implications of the findings

The ‘spontaneous’ presentation of OHSS may be confusing for clinicians. We report that FGA is an important cause of spontaneous OHSS which has well-defined biochemical and radiological characteristics, which may be treated effectively in the short-to-medium with pituitary surgery. Results of this study may provide greater awareness of FGA-induced OHSS.

Trial registration number

N/A

P-456 Differential distribution of the extracellular matrix components within the human ovarian cortex and remodelling during in vitro culture

Study question

How is the extracellular matrix (ECM) network distributed within the human ovarian cortex, and how does in vitro culture alter its structure?

Summary answer

The ECM composition varies in the different layers of the ovarian cortex and is further remodelled during in vitro culture.

What is known already

The ovarian ECM is the scaffold within which follicles and stromal cells are organised. Its composition and structural properties constantly evolve to accommodate follicle development and expansion. Culturing primordial follicles within ovarian strips enables to reproduce the exact composition and stiffness of the native ECM. Yet, tissue preparation, which involves mechanical loosening, induces modifications in the ECM network and alters cell-cell contact, leading to spontaneous follicle activation. Characterising the native ovarian cortical ECM and its dynamic changes during culture will help decipher its role during folliculogenesis and improve both in vitro activation (IVA) and in vitro growth (IVG) systems.

Study design, size, duration

Fresh ovarian cortical biopsies were obtained from 6 women aged 28–38 years (mean ± SD: 32.7 ± 4.1 years) at elective caesarean section. Biopsies were cut into fragments of ∼4 × 1×0.5 mm and cultured for 0, 2, 4 or 6 days.

Participants/materials, setting, methods

Stromal cell density as well as the percentage of ECM-related protein (collagen, elastin, fibronectin, laminin) positive area in the entire cortex were quantified at each time point using histological and immunohistological analysis. Collagen and elastin contents were further quantified within each layer of the human ovarian cortex, namely the outer cortex, the mid-cortex, and the cortex-medulla junction regions.

Main results and the role of chance

Collagen content of the cortical ECM decreased from 55.5% ± 1.7% positive area at day 0 (D0) to 42.3% ± 1.1% at D6 (p = 0.001), and elastin increased from 1.1% ± 0.2% at D0 to 1.9% ± 0.1% at D6 (p = 0.001). Fibronectin and laminin remained stable. This suggests tissue loosening during culture, in accordance with the decreased stromal cell density from 3.6x106 ± 0.6 to 2.8x106 ± 0.3 cells/mm3 at D2 (p = 0.033) with no subsequent change. Moreover, collagen and elastin distribution were uneven throughout the cortex and during culture. Collagen deposition was maximal at the outer cortex and the lowest at the mid-cortex (69.4% ± 1.6% vs 53.8% ± 1.5% positive area, p &lt; 0.001), and decreased from D0 to D2 (65.2% ± 2.0% vs 60.6% ± 2.2%, p = 0.033) then stabilised. Elastin showed the converse distribution, being most concentrated at the cortex-medulla junction (3.7% ± 0.3% vs 0.9% ± 0.2% in the outer cortex, p &lt; 0.001), and peaked at D6 compared to D0 (3.1% ± 0.3% vs 1.3% ± 0.2%, p &lt; 0.001). These data indicate a distinct phenotype of the ovarian cortical ECM depending on both its region and the culture period. Further characterisation of the differences in ECM architecture is ongoing.

Limitations, reasons for caution

Ovarian cortical biopsies were obtained from pregnant women undergoing caesarean sections. As such, the data obtained may not accurately reflect the ECM distribution of non-pregnant women.

Wider implications of the findings

Clarifying the composition and architecture signature of the ovarian cortical ECM will not only provide a foundation for further exploration of ovarian microenvironments, but also be of importance for understanding of ECM-follicle interactions maintaining the primordial pool and early growth stages leading to improvements in IVA and IVG.

Trial registration number

not applicable

P-424 Endometrial receptivity as determined by Endometrial Receptivity Analysis (ERA) can change after a successful live birth from a frozen embryo transfer (FET)

Study question

Endometrial receptivity as determined by Endometrial Receptivity Analysis (ERA) can change after a successful live birth from a frozen a frozen embryo transfer (FET)

Summary answer

27 of 33 patients with a previous live birth from FET had an altered endometrial receptivity profile by ERA after a subsequent unsuccessful FET.

What is known already

The endometrial window of implantation is approximately 24 hours wide with a complex interaction of autocrine, paracrine, and endocrine factors. Successful embryo implantation involves a 3-step process of apposition, adhesion, and invasion of an embryo into a receptive endometrium. The ERA was developed using the expression profile of 248 genes using Next Generation Sequencing to determine if the endometrium is receptive, early receptive, late receptive, pre-receptive or post-receptive to objectively determine the optimal timing of progesterone exposure prior to embryo transfer. Some studies have shown statistically significant improvements in live birth rates while other studies have shown no difference.

Study design, size, duration

Case series of 33 patients with successful live birth following euploid FET using 5 days of progesterone (P + 5) with subsequent unsuccessful FET using the same protocol from January 2018 – December 2020. 27 of 33 patients who repeated their ERA were found to be non-receptive using P + 5. The new ERA profile results were used for their next FET. Implantation and live birth rates were calculated.

Participants/materials, setting, methods

A single private practice fertility clinic performed 340 ERA cycles from January 2018 – December 2020 with 276 subsequent FET cycles. An observational study of 33 patients with a previous live birth using P + 5 elected to repeat their ERA cycle after an unsuccessful FET. Implantation and live birth rates were calculated for their subsequent FET after completing the repeat ERA.

Main results and the role of chance

Repeat ERA result for patients with a previous live birth using P + 5 revealed that 6 patients still needed P + 5 (18.2%) for a receptive endometrial profile, 8 patients (24.2%) needed an extra 12 hours (P + 5.5), 18 patients (54.5%) needed an extra 24 hours (P + 6) and only one patient (3.0%) needed an extra 48 hours (P + 7). No patient that repeated their ERA after a previous live birth had a post-receptive profile (P + 4 or P + 4.5) and one patient had successful live births after using 3 different ERA profiles (P + 5, P + 6 and P + 7). All patients except one had repeat ERA results that were pre-receptive with only one patient changing from P + 6 to P + 5. FET cycles using P + 5 and P + 7 had a 100% implantation and pregnancy rate, while patients using P + 5.5 had the lowest implantation rate (62.5%) and live birth rate (37.5%). Patients with an ERA profile of P + 6 had an implantation rate of 94.1% and live birth rate of 88.2%. The small number of patients in this case series make a type I error possible because of the low number of patients in each ERA profile category with insufficient power to reach statistical significance.

Limitations, reasons for caution

Implantation rate for the clinic during the study period was 75% and live birth rate of 68% using euploid embryos. Our high baseline implantation and live birth rates, coupled with low numbers of patients in this observational study, make these results less generalizable to the IVF population at large.

Wider implications of the findings

It is widely accepted that ERA results are reproducible and do not change during a woman’s reproductive life. These results suggest that some women may have an altered window of receptivity after both successful and unsuccessful FET cycles. It may be reasonable to repeat ERA cycles for carefully selected patients.

Trial registration number

N/A

Assessment of the efficacy of clofazimine alone and in combination with primary agents against Mycobacterium tuberculosis in vitro

OBJECTIVES

The chemotherapeutic regimens of drug-susceptible (DS)-tuberculosis (TB) patients comprise four primary anti-TB drugs; rifampicin (RMP), isoniazid (INH), ethambutol (EMB) and pyrazinamide (PZA), administered for six-to-nine months. These drug regimens target the various microbial populations that include actively-replicating (AR), slow-replicating (SR) and non-replicating (NR) organisms. Clofazimine (CFZ) has showed benefit in shortening DS-TB treatment in vivo from six to four months when used in combination with this regimen in murine models of experimental infection. However, its antimicrobial efficacy when used in combination with the primary drugs against the various microbial populations of Mycobacterium tuberculosis has not been demonstrated.

METHODS

In the current in vitro study, the inhibitory and bactericidal activities of CFZ in combination with the primary anti-TB drugs, RMP, INH and EMB against the AR and SR organisms in planktonic and biofilm-forming cultures, respectively, were evaluated by fractional inhibitory concentration index (FICI) and fractional bactericidal concentration index (FBCI) determinations, using the Loewe Additivity Model.

RESULTS

In planktonic cultures, CFZ demonstrated synergistic growth inhibitory activity in combination with RMP and INH individually and collectively. With respect to bactericidal activity, CFZ exhibited synergistic activity only in a two-drug combination with RMP. However, in biofilm-forming cultures, all CFZ-containing anti-TB drug combinations exhibited synergistic inhibitory and bactericidal effects, particularly in combination with RIF and INH.

CONCLUSION

Clofazimine exhibited synergistic effects in combination with primary anti-TB drugs against both planktonic and biofilm-forming cultures, showing potential benefit in augmenting treatment outcome when used during standard TB chemotherapy.

Fate and transport in environmental quality

Changes in pollutant concentrations in environmental media occur both from pollutant transport in water or air and from local processes, such as adsorption, degradation, precipitation, straining, and so on. The terms "fate and transport" and "transport and fate" reflect the coupling of moving with the carrier media and biogeochemical processes describing local transformations or interactions. The Journal of Environmental Quality (JEQ) was one of the first to publish papers on fate and transport (F&T). This paper is a minireview written to commemorate the 50th anniversary of JEQ and show how the research interests, methodology, and public attention have been reflected in fate and transport publications in JEQ during the last 40 years. We report the statistics showing how the representation of different pollutant groups in papers changed with time. Major focus areas have included the effect of solution composition on F&T and concurrent F&T, the role of organic matter, and the relative role of different F&T pathways. The role of temporal and spatial heterogeneity has been studied at different scales. The value of long-term F&T studies and developments in modeling as the F&T research approach was amply demonstrated. Fate and transport studies have been an essential part of conservation measure evaluation and comparison and ecological risk assessment. For 50 years, JEQ has delivered new insights, methods, and applications related to F&T science. The importance of its service to society is recognized, and we look forward to new generations of F&T researchers presenting their contributions in JEQ.

P–720 Prevalence of Female Infertility in the UK Armed Forces

Study question

What is the prevalence of female infertility among UK military personnel and does it differ from the Metropolitan Police Service (MPS) and civilian populations?

Summary answer

Prevalence of self-reported infertility was higher in servicewomen (31.7%) and female MPS officers (36.3%) than in civilian women (24.4%).

What is known already

Arduous employment is associated with numerous potential occupational hazards and behaviours that may be relevant to fertility. These include physical and psychological stress, smoking, alcohol drinking and other lifestyle factors. A preliminarily report in 2016 indicated that UK servicewomen over 30 years of age were more likely to present with fertility problems compared with reported civilian infertility data for age-matched women. Few previous studies have compared infertility prevalence of servicewomen with civilians, and none have compared infertility prevalence with other occupations.

Study design, size, duration

A cross-sectional study was undertaken in 2019 to determine prevalence of infertility. All eligible UK servicewomen (14,650) and MPS officers (8,262) aged 18–60 years were invited to participate with sisters of participants recruited as controls using a snowball technique. Data including pregnancy history, time to each pregnancy and self-reported infertility risk-factors were collected using an online questionnaire. We estimated a sample of 4898 servicewomen would give a precision of 1% around infertility prevalence estimates.

Participants/materials, setting, methods

The questionnaire was developed, piloted and adapted for electronic distribution. The occupational groups were invited by email to complete the questionnaire on three occasions. Prevalence of infertility was defined as the proportion of women at risk of pregnancy who had not become pregnant within 12 months. Only women with pregnancy outcomes, or fully tested for fertility (12 months or more of exposure), were included in the denominator.

Main results and the role of chance

Participants included 4806 (33%) women serving in the UK Armed Forces, 1237 (15%) female MPS officers and 435 (estimated 8%) non-military, non-MPS sisters (biological, half, step or adopted) of both groups. 98.4% of responses were complete. Prevalence of self-reported 12-month infertility was 31.7% (95% CI 29.9–33.5) in servicewomen, 36.3% (95% CI 33.1–39.7) in MPS officers and 24.4% (95% CI 19.6–29.8) in civilian women. Age, history of polycystic ovary syndrome, endometriosis, fibroids, tubal and pelvic surgery, hysterectomy and a short General Health Questionnaire (GHQ 12) score of &gt; 4 (suggesting a minor psychiatric disorder) were associated with infertility and adjusted for in logistic regression models to estimate odds ratios. The adjusted odds ratio (aOR) of infertility in servicewomen was 1.0 (95% CI 0.8–1.2) compared with MPS officers and 1.5 (95% CI 1.1–2.0) in both servicewomen and MPS officers compared with sisters.

Limitations, reasons for caution

The major limitation is the low response rate, particularly in the two control groups, potentially resulting in response bias. Prevalence of infertility could have been further over-estimated if fertile women are more likely to have left the military or MPS. There is scope for residual confounding.

Wider implications of the findings: Further analyses will explore the key risk factors to identify what aspects of these occupations contribute to infertility and which may be modifiable. Future cohort studies would be helpful to extend the understanding of the influence of occupation on infertility.

Trial registration number

Not applicable

P–758 The efficacy, safety and proven security of microSecure vitrification offers “peace of mind” and reliability during a global pandemic

Study question

Under deadly pandemic conditions involving the novel SARS-CoV–2 corona virus, could biopsied blastocysts be safely cryopreserved, stored and utilized for subsequent warming cycles?

Summary answer

Blastocysts were securely stored, effectively warmed and safely transferred to yield normal pregnancy outcomes under uncertain laboratory conditions subject to unprecedented policy changes.

What is known already

By April 2020, every IVF lab worldwide was implementing deep cleaning/disinfecting procedures in their laboratory and patient-contact areas, thorough hand-washing policies and mandatory PPE to reduce the chance of contact transmission and spread of the potentially deadly SARS-CoV–2 coronavirus. Furthermore, we know that safeguards like oil overlay culture dishes and pipetting dilution factors provide insurance against possible contamination. However, knowing that the trophectoderm of blastocysts possessed the ACE–2 binding receptor, potential concern existed regarding the continuation of laser zona opening and biopsy procedures that could possibly expose cryopreserved embryos to the coronavirus in liquid nitrogen storage (vapor or liquid).

Study design, size, duration

Between March 8 and December 22, 2020, 508 patients performed FET cycles involving the use of single (n = 490) or dual (n = 18) euploid microSecure vitrified blastocysts. In this retrospective analysis, we compared clinical pregnancy outcomes to a 5 year dataset (2015–2019) encompassing 2768 single and 272 dual embryo transfer FET cycles. All blastocysts were vitrified using a closed microSecure system and Innovative Cryoenterprise (ICE; NJ, USA) non-DMSO, glycerol-EG solutions. Differences were assessed by Chi-square analysis (p < 0.05).

Participants/materials, setting, methods

Deep cleaning was performed with Simple Green Pro3+ Virucide in non-lab areas (e.g., ET rooms, waiting room) and 6% H2O2 & OoSafe solutions to disinfect lab surfaces and equipment. Group embryo cultures were performed in MCO–5M humidified incubators under low oxygen tri-gas conditions with varying CO2 levels (5.3–6.0%; pH = 7.3–7.35) using 25µl droplets of LifeGlobal medium+7.5%LGPS+1%sodium hyaluronate, before changing to 10µl droplet/GPS dishes post-biopsy. FET cycles involved 4-step sucrose dilutions and transvaginal ultrasound-guided embryo transfers.

Main results and the role of chance

While ICSI fertilization rates were unchanged in 2020 (79.4% 2PN vs 77.3%), blastocyst utilization rates tended to be slightly lower than past years (56.4% vs 59.9%) but within an acceptable range. Of 529 blastocysts warmed, 527 (99.7%) survived completely for transfer, being comparable to the 99.4% experienced over 5 years. Furthermore, there was no differences detected in single embryo transfer pregnancy outcomes. The implantation and ongoing clinical pregnancy/live birth rates were 69% and 66.53% compared to 70.4% and 65.1%, respectively. Under pandemic conditions we did not observe an increase in biochemical pregnancies (10.3%) nor spontaneous miscarriage rates (7.8%). Although it is possible that our rigorous disinfection practices could have attributed to lower blastocyst production, the viability of those embryos was not compromised. Importantly, we were able to feel comfortable performing micromanipulation and cryopreservation procedures throughout the year knowing that we were effectively eliminating possible vertical transmission of coronavirus to an exposed trophectoderm layer in cryostorage by applying mircoSecure vitrification. Post-FET clinical check-ups revealed no patient reporting any fever or other Covid–19 symptoms in the weeks following their transfers. We are fortunate to say that our Lab staff, physicians and patients have remained healthy throughout 2020.

Limitations, reasons for caution

Blastocyst survival and viability are independent of possible viral exposure. Previously, the risk of disease transmission via liquid nitrogen or vapor exposure was considered highly unlikely (Pomeroy et al., 2010), but that was at a time when embryos were primarily zona-enclosed. Today’s ART standards have us re-evaluating safer approaches.

Wider implications of the findings: We have effectively mitigated avoiding performing zona opening procedures by employing our standard practice of aseptic, closed vitrification. In combination with standard preventative measures (PPE, hand hygiene, distance awareness) and routine deep cleaning practices, we sustained a contamination-free environment and healthy patients, capable of sustaining high levels of pregnancy success.

Trial registration number

Not applicable

P–437 The ovaries of transgender men indicate effects of high dose testosterone on the primordial and early growing follicle pool

Study question

Does high-dose testosterone therapy affect the stage distribution, morphological health and DNA damage repair capacity of human ovarian follicles and their survival in vitro?

Summary answer

Testosterone exposure is associated with reduced follicle growth activation, reduced follicle health and increased DNA damage: these further deteriorate after six days of culture. What is known already: Androgens have diverse actions within the ovary, however, there is a lack of information regarding the long-term effects of high-dose testosterone on ovarian function and reproductive potential. Cumulus-oocyte complexes recovered from transgender men have been successfully matured in-vitro but little is known regarding the impact of this gender affirming endocrine therapy on the primordial follicle pool. Study design, size, duration: Whole ovaries were obtained from four transgender men aged 25–36 years with informed consent at oophorectomy. All patients had received 1000mg testosterone undecanoate intramuscularly at 12–16 week intervals for a minimum of 4 years pre-operatively. Cortical tissues were dissected into small pieces (≈1x1x0.5mm) and either immediately fixed for histological analysis or cultured for 6 days. Testosterone-treated ovaries were compared to cortical biopsies from age-matched healthy women obtained at caesarean section (n = 4, age 26–36). Participants/materials, setting, methods: Follicle number, classification of developmental stage and morphology were evaluated by histological analysis of ovarian cortical tissue from day 0 and 6 days post culture. Immunohistochemical analysis included γH2AX as a marker of DNA damage, and meiotic recombination 11 (MRE11), ataxia telangiectasia mutated (ATM) and Rad51 as DNA repair proteins. A total of 3802 follicles from testosterone exposed and 878 from control ovaries were analysed. Main results and the role of chance: At day 0 (D0), transgender tissue had a higher proportion of non-growing follicles (92.7±1.7%) compared to control (85.4±6.2%, p &lt; 0.05) but a lower proportion of morphologically healthy follicles (non-growing 59%, primary 61%, secondary 36%; vs 83%, 75%, 80% in controls, all p &lt; 0.005). After 6 days in culture, the proportion of growing follicles increased (51.3% vs 46.5%) but follicle health further declined (all stages p &lt; 0.005).

DNA damage was assessed by expression of γH2AX. At D0, the proportion of oocytes showing DNA damage was significantly higher in transgender non-growing follicles (48.1±12.5%, vs 12.3±0.25%, p &lt; 0.005). After culture, γH2AX expression increased in both transgender (p &lt; 0.005) and controls (p &lt; 0.005) but remained higher in transgender oocytes (non-growing 72.2%, primary 71.7% vs 27.3%, 46.2%, all p &lt; 0.05). At D0, there was no difference in expression of DNA repair enzymes ATM and RAD51 between transgender and control oocytes, and increased expression of MRE11 in control non-growing follicles (p &lt; 0.05). Post-culture, there was a significant increase in ATM expression in transgender non-growing oocytes compared to control (98.5% vs 77.8%, p &lt; 0.05) and a less marked decline in RAD51 expression(p &lt; 0.05). The expression of MRE–11 in control non-growing oocytes dramatically declined (100% to 58.2%, p &lt; 0.05), unlike in transgender tissue where expression was comparable to D0.

Limitations, reasons for caution

A large number of follicles have been analysed, but only from a small number of ovaries. DNA damage at D0 and after 6 days of culture may not reflect DNA damage and repair capacity at later stages of follicle growth. The effect of duration of testosterone treatment was not investigated.

Wider implications of the findings: These data indicate that high circulating concentrations of testosterone have previously unrecognised effects on the primordial and small-growing follicles of the ovary. These results may have implications for transgender men receiving gender-affirming therapy prior to considering pregnancy or fertility preservation measures.

Trial registration number

n/a

P-437 The ovaries of transgender men indicate effects of high dose testosterone on the primordial and early growing follicle pool

Study question

Does high-dose testosterone therapy affect the stage distribution, morphological health and DNA damage repair capacity of human ovarian follicles and their survival in vitro?

Summary answer

Testosterone exposure is associated with reduced follicle growth activation, reduced follicle health and increased DNA damage: these further deteriorate after six days of culture. 

What is known already

Androgens have diverse actions within the ovary, however, there is a lack of information regarding the long-term effects of high-dose testosterone on ovarian function and reproductive potential. Cumulus-oocyte complexes recovered from transgender men have been successfully matured in-vitro but little is known regarding the impact of this gender affirming endocrine therapy on the primordial follicle pool

Study design, size, duration

Whole ovaries were obtained from four transgender men aged 25-36 years with informed consent at oophorectomy. All patients had received 1000mg testosterone undecanoate intramuscularly at 12-16 week intervals for a minimum of 4 years pre-operatively. Cortical tissues were dissected into small pieces (≈1x1x0.5mm) and either immediately fixed for histological analysis or cultured for 6 days. Testosterone-treated ovaries were compared to cortical biopsies from age-matched healthy women obtained at caesarean section (n = 4, age 26-36). 

Participants/materials, setting, methods

Follicle number, classification of developmental stage and morphology were evaluated by histological analysis of ovarian cortical tissue from day 0 and 6 days post culture. Immunohistochemical analysis included γH2AX as a marker of DNA damage, and meiotic recombination 11 (MRE11), ataxia telangiectasia mutated (ATM) and Rad51 as DNA repair proteins. A total of 3802 follicles from testosterone exposed and 878 from control ovaries were analysed. 

Main results and the role of chance

At day 0 (D0), transgender tissue had a higher proportion of non-growing follicles (92.7±1.7%) compared to control (85.4±6.2%, p &lt; 0.05) but a lower proportion of morphologically healthy follicles (non-growing 59%, primary 61%, secondary 36%; vs 83%, 75%, 80% in controls, all p &lt; 0.005). After 6 days in culture, the proportion of growing follicles increased (51.3% vs 46.5%) but follicle health further declined (all stages p &lt; 0.005).

DNA damage was assessed by expression of γH2AX. At D0, the proportion of oocytes showing DNA damage was significantly higher in transgender non-growing follicles (48.1±12.5%, vs 12.3±0.25%, p &lt; 0.005). After culture, γH2AX expression increased in both transgender (p &lt; 0.005) and controls (p &lt; 0.005) but remained higher in transgender oocytes (non-growing 72.2%, primary 71.7% vs 27.3%, 46.2%, all p &lt; 0.05). 

At D0, there was no difference in expression of DNA repair enzymes ATM and RAD51 between transgender and control oocytes, and increased expression of MRE11 in control non-growing follicles (p &lt; 0.05). Post-culture, there was a significant increase in ATM expression in transgender non-growing oocytes compared to control (98.5% vs 77.8%, p &lt; 0.05) and a less marked decline in RAD51 expression(p &lt; 0.05). The expression of MRE-11 in control non-growing oocytes dramatically declined (100% to 58.2%, p &lt; 0.05), unlike in transgender tissue where expression was comparable to D0.

Limitations, reasons for caution

A large number of follicles have been analysed, but only from a small number of ovaries. DNA damage at D0 and after 6 days of culture may not reflect DNA damage and repair capacity at later stages of follicle growth. The effect of duration of testosterone treatment was not investigated.

Wider implications of the findings

These data indicate that high circulating concentrations of testosterone have previously unrecognised effects on the primordial and small-growing follicles of the ovary. These results may have implications for transgender men receiving gender-affirming therapy prior to considering pregnancy or fertility preservation measures. 

Trial registration number

n/a

A comparison of porewater chemistry between intact, afforested and restored raised and blanket bogs

Afforestation is a significant cause of global peatland degradation. In some regions, afforested bogs are now undergoing clear-felling and restoration, often known as forest-to-bog restoration. We studied differences in water-table depth (WTD) and porewater chemistry between intact, afforested, and restored bogs at a raised bog and blanket bog location. Solute concentrations and principal component analysis suggested that water-table drawdown and higher electrical conductivity (EC) and ammonium (NH₄-N) concentrations were associated with afforestation. In contrast, higher dissolved organic carbon (DOC) and phosphate (PO₄-P) concentrations were associated with deforestation. Drying-rewetting cycles influenced seasonal variability in solute concentrations, particularly in shallower porewater at the raised bog location. WTD was significantly deeper in the oldest raised bog restoration site (~9 years post-restoration) than the intact bog (mean difference = 6.2 cm). However, WTD in the oldest blanket bog restoration site (~17 years post-restoration), where furrows had been blocked, was comparable to the intact bog (mean difference = 1.2 cm). When averaged for all porewater depths, NH₄-N concentrations were significantly higher in the afforested than the intact sites (mean difference = 0.77 mg L^-1) whereas significant differences between the oldest restoration sites and the intact sites included higher PO₄-P (mean difference = 70 μg L^-1) in the raised bog and higher DOC (mean difference = 5.6 mg L^-1), EC (mean difference = 19 μS cm^-1) and lower SUVA₂₅₄ (mean difference = 0.13 L mg^-1 m^-1) in the blanket bog. Results indicate felled waste (brash) may be a significant source of soluble C and PO₄-P. Mean porewater PO₄-P concentrations were between two and five times higher in furrows and drains in which brash had accumulated compared to other locations in the same sites where brash had not accumulated. Creating and maintaining brash-free buffer zones may therefore minimise freshwater impacts.

Supportive care in patients with cancer during the COVID-19 pandemic

Cancer care has been profoundly impacted by the global pandemic of severe acute respiratory syndrome coronavirus 2 disease (coronavirus disease 2019, COVID-19), resulting in unprecedented challenges. Supportive care is an essential component of cancer treatment, seeking to prevent and manage chemotherapy complications such as febrile neutropenia, anaemia, thrombocytopenia/bleeding, thromboembolic events and nausea/vomiting, all of which are common causes of hospitalisation. These adverse events are an essential consideration under routine patient management, but particularly so during a pandemic, a setting in which clinicians aim to minimise patients' risk of infection and need for hospital visits. Professional medical oncology societies have been providing updated guidelines to support health care professionals with the management, treatment and supportive care needs of their patients with cancer under the threat of COVID-19. This paper aims to review the recommendations made by the most prominent medical oncology societies for devising and modifying supportive care strategies during the pandemic.

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Cancer care has been profoundly impacted by the global pandemic of COVID-19, resulting in unprecedented challenges.

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Oncology societies have updated guidelines for the supportive care needs of patients with cancer under the threat of COVID-19.

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This paper reviews recommendations from prominent oncology societies for providing supportive care during the pandemic.

Clinical summary guide: reproduction in women with previous abdominopelvic radiotherapy or total body irradiation

STUDY QUESTION

What is the evidence to guide the management of women who wish to conceive following abdominopelvic radiotherapy (AP RT) or total body irradiation (TBI)?

SUMMARY ANSWER

Pregnancy is possible, even following higher doses of post-pubertal uterine radiation exposure; however, it is associated with adverse reproductive sequelae and pregnancies must be managed in a high-risk obstetric unit.

WHAT IS KNOWN ALREADY

In addition to primary ovarian insufficiency, female survivors who are treated with AP RT and TBI are at risk of damage to the uterus. This may impact on its function and manifest as adverse reproductive sequelae.

STUDY DESIGN SIZE DURATION

A review of the literature was carried out and a multidisciplinary working group provided expert opinion regarding assessment of the uterus and obstetric management.

PARTICIPANTS/MATERIALS SETTING METHODS

Reproductive outcomes for postpubertal women with uterine radiation exposure in the form of AP RT or TBI were reviewed. This included Pubmed listed peer-reviewed publications from 1990 to 2019, and limited to English language..

MAIN RESULTS AND THE ROLE OF CHANCE

The prepubertal uterus is much more vulnerable to the effects of radiation than after puberty. Almost all available information about the impact of radiation on the uterus comes from studies of radiation exposure during childhood or adolescence.An uncomplicated pregnancy is possible, even with doses as high as 54 Gy. Therefore, tumour treatment doses alone cannot at present be used to accurately predict uterine damage.

LIMITATIONS REASONS FOR CAUTION

Much of the data cannot be readily extrapolated to adult women who have had uterine radiation and the publications concerning adult women treated with AP RT are largely limited to case reports.

WIDER IMPLICATIONS OF THE FINDINGS

This analysis offers clinical guidance and assists with patient counselling. It is important to include patients who have undergone AP RT or TBI in prospective studies to provide further evidence regarding uterine function, pregnancy outcomes and correlation of imaging with clinical outcomes.

STUDY FUNDING/COMPETING INTERESTS

This study received no funding and there are no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Brief review: Cardiac complications and platelet activation in COVID-19 infection

COVID-19 pneumonia, much like that of bacterial and viral community-acquired pneumonia before it, is accompanied by a high rate of cardio- and cerebrovascular events that are associated with an increased risk of complications and a greater mortality. Although the mechanisms underlying the pathogenesis of these adverse events are not entirely clear and may be multifactorial, platelets appear to have a prominent aetiologic role and this, together with an overview of the clinical evidence, forms the basis of this short review.

Tamm plasmons in metal/nanoporous GaN distributed Bragg reflector cavities for active and passive optoelectronics

We theoretically and experimentally investigate Tamm plasmon (TP) modes in a metal/semiconductor distributed Bragg reflector (DBR) interface. A thin Ag (silver) layer with a thickness (55 nm from simulation) that is optimized to guarantee a low reflectivity at the resonance was deposited on nanoporous GaN DBRs fabricated using electrochemical (EC) etching on freestanding semipolar (2021¯) GaN substrates. The reflectivity spectra of the DBRs are compared before and after the Ag deposition and with that of a blanket Ag layer deposited on GaN. The experimental results indicate the presence of a TP mode at ∼ 454 nm on the structure after the Ag deposition, which is also supported by theoretical calculations using a transfer-matrix algorithm. The results from mode dispersion with energy-momentum reflectance spectroscopy measurements also support the presence of a TP mode at the metal-nanoporous GaN DBR interface. An active medium can also be accommodated within the mode for optoelectronics and photonics. Moreover, the simulation results predict a sensitivity of the TP mode wavelength to the ambient (∼ 4-7 nm shift when changing the ambient within the pores from air with n = 1 to isopropanol n = 1.3), suggesting an application of the nanoporous GaN-based TP structure for optical sensing.

P2531Impact of age on clinical outcomes after PCI in patients with ACS and stable CAD treated with 23-month ticagrelor monotherapy following 1-month DAPT in the randomized GLOBAL LEADERS study

Background

The efficacy and safety of ticagrelor monotherapy in elderly patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) or stable coronary artery disease (CAD) has not been evaluated.

Purpose

To evaluate the efficacy and safety of ticagrelor monotherapy following 1-month dual antiplatelet therapy (DAPT) after PCI in relation to age and clinical presentation in the GLOBAL LEADERS study cohort.

Methods

This is a subanalysis of the randomized multicentre GLOBAL LEADERS study, comparing the experimental strategy of 23-month ticagrelor monotherapy after 1 month of ticagrelor and aspirin with the reference strategy of 12-month DAPT followed by 12-month aspirin monotherapy in 15991 patients undergoing PCI. Patients were categorized into elderly and very elderly according to a pre-specified cut-off of 75 years and a post-hoc defined cut-off of 80 years. Impact of age and clinical presentation (ACS versus stable CAD) on clinical outcome at 2 years was evaluated. The primary endpoint was a composite of all-cause mortality or nonfatal, centrally adjudicated, new Q-wave myocardial infarction.

Results

In the overall elderly (>75 years) population (n=2565), primary endpoint occurred in 7.2% of patients in the experimental group and in 9.4% of patients in the reference group (p=0.041) at 2 years (p int =0.23). Elderly patients in the experimental group had a lower rate of definite stent thrombosis (ST) (0.2% vs. 0.9%, p=0.043, p int=0.03), definite or probable ST (0.4 vs. 1.3%, p=0.015, p int=0.01) and a numerically higher rates of BARC 3 or 5 type bleeding (5.0% vs. 3.9%, p=0.192, p int=0.06), when compared to the reference arm.

Among elderly patients presenting with ACS both treatment groups did not differ in the rates of primary endpoint (9.1% vs. 10.8%, p=0.367) and BARC 3 or 5 type bleeding (4.7% vs. 5.7%, p=0.458), whereas among elderly patients with stable CAD the experimental strategy was associated with numerically lower rates of the primary endpoint (5.7% vs. 8.4%, p=0.046) (p int =0.42) and a higher rate of BARC 3 or 5 type bleedings (5.3% vs. 2.6%, p=0.012) (p int =0.02) at 2 years.

Exploratory analyses among very elderly (≥80 years) patients (n=1169) indicated no significant differences between treatment groups in the rates of the primary endpoint (10.2% vs. 11.7% p=0.411, p int=0.940) and BARC 3 or 5 type bleeding (6.0% vs. 5.3%, p=0.630, p int=0.514) at 2 years.

Conclusions

The efficacy and safety of the experimental treatment strategy of 23-month ticagrelor monotherapy after 1-month DAPT following PCI was not identified as age-dependent. Among elderly patients the anti-ischemic benefit was derived at the expense of increased rate of BARC 3 or 5 type bleeding in stable CAD subgroup, but not in ACS subgroup.

Acknowledgement/Funding

European Clinical Research Institute, which received unrestricted grants from Biosensors International, AstraZeneca, and the Medicines Company.

Female cognitive performance and mass are correlated with different aspects of mate choice in the zebra finch (Taeniopygia guttata)

A female's cognitive ability may influence her mate preferences through various mechanisms. These mechanisms include the direct effect of cognitive ability on the information-processing skills used during mate choice, and the indirect effect of cognitive ability on quality when females mate assortatively. Here, we examined whether the ability to learn a novel foraging task, a cognitive skill which has been associated with reproductive success in other capacities, was correlated with song preferences in female zebra finches (Taeniopygia guttata). Female preferences were measured in an operant testing chamber where hops on a perch triggered song playback. Females were given the choice of (1) conspecific vs. heterospecific song and (2) high-quality male vs. low-quality male conspecific song. We found that female performance on the novel foraging task was positively correlated with preference for conspecific song, but not with preference for high-quality male song. Instead, female mass was positively correlated with preference for high-quality male song, potentially signifying that female mass is a stronger predictor of female quality in assortative mating than female cognitive performance. Female mass and cognitive performance were unrelated. Our results suggest that the particular traits of a female that affect conspecific preference do not necessarily affect preference for high-quality males.