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 < 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 < 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 < 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 < 0.005). After culture, γH2AX expression increased in both transgender (p < 0.005) and controls (p < 0.005) but remained higher in transgender oocytes (non-growing 72.2%, primary 71.7% vs 27.3%, 46.2%, all p < 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 < 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 < 0.05) and a less marked decline in RAD51 expression(p < 0.05). The expression of MRE-11 in control non-growing oocytes dramatically declined (100% to 58.2%, p < 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.

Evaluation of the Efficacy of Three Direct Fed Microbial Cocktails To Reduce Fecal Shedding of Escherichia coli O157:H7 in Naturally Colonized Cattle and Fecal Shedding and Peripheral Lymph Node Carriage of Salmonella in Experimentally Infected Cattle

Two experiments were conducted to evaluate the feeding of direct fed microbials (DFMs) on fecal shedding of Escherichia coli O157:H7 in naturally infected cattle (experiment I) and on Salmonella in the feces and peripheral lymph nodes (PLNs) of experimentally infected cattle (experiment II). Thirty cattle, 10 per treatment, were used in each experiment. Treatments in experiment I consisted of a control (lactose carrier only); DFM1, a 1:1 ratio of Enterococcus faecium and Lactobacillus animalis; and DFM2, a 1:1 ratio of Lactobacillus acidophilus and Pediococcus acidilactici. In Experiment II, DFM1 was replaced with DFM3, a 1:2 ratio of Lactobacillus reuteri and other Lactobacillus strains. Additives were mixed in water and applied as a top-dressing to each pen's daily ration for 50 days. Approximately half-way through each experiment, the DFM concentration was doubled for the remainder of the study. Fecal samples were collected throughout experiment I and cultured for E. coli O157:H7. Cattle in experiment II were inoculated intradermally with Salmonella Montevideo on days 32, 37, and 42 and then necropsied on days 49 and 50 (five cattle per treatment on each day). Innate immune function was assessed on days 29, 49, and 50. In experiment I, fecal concentration and prevalence of E. coli O157:H7 were not different (P > 0.10) nor was there an effect (P = 0.95) on the percentage of super shedders (cattle shedding ≥3.0 log CFU/g of feces). In experiment II, no treatment differences (P > 0.05) were observed for Salmonella in the PLNs except for the inguinal nodes, which had a significantly lower Salmonella prevalence in DFM-supplemented cattle than in the controls. Immune function, as measured by monocyte nitric oxide production and neutrophil oxidative burst, was decreased (P < 0.05) in the DFM treatment groups. Although results of this research indicate little to no effect of these DFMs on E. coli O157:H7 or Salmonella in cattle, an increase in the duration of administration to that similar to what is used for commercial cattle might elicit treatment differences.

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.