Realizing topologically ordered states on a quantum processor

[Figure: see text].

206 EXPLORING THE RELATIONSHIP BETWEEN LONELINESS, FRAILTY, AND HEALTHCARE UTILISATION IN IRELAND’S OLDER ADULTS DURING THE COVID-19 PANDEMIC

Background

The COVID-19 pandemic has disproportionately affected older adults, both in morbidity and mortality¹. The effects of the pandemic go beyond contracting the SARS-CoV-2 virus, leading to devastating consequences, particularly for individuals over the age of 60. In Ireland, isolation in older adults was exacerbated by cocooning measures and geographical limitations. The purpose of this study was to explore the relationship between loneliness, frailty, and the utilisation of health services in a sample of sexagenarians in Ireland.

Methods

Adults aged 60–70 attending COVID-19 vaccine appointments at a Level 3 Hospital in Ireland (n = 75) were invited to participate in a 36-item questionnaire. Participants reported demographic information and questions regarding physical well-being, healthcare utilisation, lifestyle and behaviours, and impact of vaccination. The survey also included three validated questionnaires: PRISMA-7 for frailty, SARC-F for sarcopenia, and the UCLA 3-Item Loneliness Scale (UCLA-3ILS).

Results

Of the 75 survey respondents, the mean age was 63.2. 72% (n = 54) identified as female. 28% (n = 21) reported that they had been cocooning during the past year. While 84% (n = 63) of respondents reported that they cancelled routine medical appointments during the pandemic, none reported avoiding attending hospital. Five respondents met the criteria for frailty and four were identified as probable sarcopenic. There was no significant difference (p = 0.64) in mean scores on the UCLA 3-ILS between frail and non-frail individuals. Persons identified as sarcopenic were more likely to have higher scores on the UCLA-3ILS (p = 0.0005).

Conclusion

This research highlights the multifaceted relationship between frailty, loneliness, and healthcare utilisation among Irish adults ages 60–70 during the COVID-19 pandemic. Future research in program, policy, and intervention development for at-risk older adults, particularly those who are frail, sarcopenic, and/or lonely, can work to reduce associated negative outcomes.

Reference

1. Kang S-J and Jung, SI. (2020). Age-Related Morbidity and Mortality among Patients with COVID-19. Infect Chemother., 52(2): 154–164.

Winter and spring atmospheric rivers in High Mountain Asia: climatology, dynamics, and variability

Atmospheric rivers (ARs) that reach the complex terrain of High Mountain Asia (HMA) cause significant hydrological impacts for millions of people. While ARs are often associated with precipitation extremes and can cause floods and debris flows affecting populated communities, little is known about ARs that reach as far inland as HMA. This paper characterizes AR types and investigates dynamical mechanisms associated with the development of ARs that typically affect HMA. Combined empirical orthogonal function (cEOF) analysis using integrated water vapor transport (IVT) is applied to days where an AR reaches HMA. K-means cluster analysis applied to the first two principal components uncovered three subtypes of AR events with distinct synoptic characteristics during winter and spring months. The first subtype increases precipitation and IVT in Western HMA and is associated with a zonally oriented wave train propagating within the westerly jet waveguide. The second subtype is associated with enhanced southwesterly IVT, anomalous upper-level cyclonic circulation centered on 45 ∘ E, and precipitation in Northwestern HMA. The third subtype shows anomalous precipitation in Eastern HMA and southwesterly IVT across the Bay of Bengal. Interannual variations in the frequency of HMA ARs and relationships with various teleconnection patterns show that western HMA AR subtypes are sensitive to well-known remote large-scale climate factors, such as the El Niño Southern Oscillation, Arctic Oscillation, and the Siberian High. These results provide synoptic characterization of the three types of ARs that reach HMA and reveal the previously unexplored significance of their contribution to winter and spring precipitation.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s00382-021-06008-z.

1174 The Reporting of Centre and Surgeon Experience in Studies of Robot Assisted Cholecystectomy: A Systematic Review

Introduction

Over 90% of cholecystectomies are performed using minimally invasive techniques. Robotic cholecystectomy (RC) has been developed to overcome technical limitations of laparoscopy, including improved range of movement and visualisation. Despite becoming increasingly widespread, the safety and efficacy of RC remain unestablished. This review aims to analyse the quality assurance reporting through centre and surgeon expertise in RC.

Method

A systematic search was conducted to identify all published studies reporting RC. Data on quality assurance measures were collected, including: centres involved, surgeons’ experience and training.

Results

Of the 1425 abstracts screened, 90 full-text papers were included. Sixty-four studies (71%) were single institutions. Of the thirty studies (33%) reporting centre type, 28 were conducted in specialist/regional/tertiary centres. Only four stated their caseload of RC. No studies described pre-specified criteria or minimum experience required for a surgeon to participate. Fifty-two (58%) reported the number of surgeons operating and 13 (14%) stated surgeons’ training grade. Two quantified previous RC experience, 7 stated prior laparoscopic experience. Only 21 (23%) described training prior to the surgeons’ first in-human procedure; animal based (n = 12), simulation (n = 12), observation (n = 4), lab-based (n = 3). Specific mentorship was reported in 8 studies, and 13 described dual operating.

Conclusions

Little information was provided about the experience and training of operating surgeons, making it difficult to ascertain whether replicable techniques were utilised which would allow development of a learning curve. This highlights the need for better transparency when reporting surgical innovation, to ensure the safe, evidence-based adoption of new technologies into clinical practice.

692 A Machine Learning Approach to Predict the Postoperative Length of Stay After Coronary Artery Bypass Grafting Using Preoperative Characteristics

Aim

Lengthy hospital length of stay (LOS) has a direct impact on healthcare costs. We aimed to design predictive models of prolonged LOS after coronary artery bypass grafting (CABG) with only preoperative characteristics and machine learning (ML) strategies.

Method

In a single centre retrospective analysis, 2,082 consecutive patients underwent first-time elective/urgent CABG: 1,262 has a short postoperative LOS (≤ 6 days) while the remaining 820 had a long LOS (> 6 days). 70/30 training/testing ratio and resampling methods were used, and cross-validation was conducted.

Results

The two groups differ significantly in terms of pre-operative variables: short LOS patients were younger (p < 0.01), more frequently male (p < 0.01) with lower BMI (p < 0.01) and better angina class (p < 0.01) and NYHA class (p < 0.01). Moreover, they had lower incidence of hypertension (p = 0.04), COPD (p < 0.01) and PVD (p < 0.01). The Logistic Euroscore was also better in this group (median 0.02 vs 0.03, p < 0.01). The predictive abilities of the ML models were as follows: logistic regression: Area under the Curve (AUC) = 0.71, accuracy = 0.69; Generalized additive model: AUC= 0.7, Accuracy = 0.68; Random Decision Forest: AUC = 0.7, Accuracy = 0.68; Naïve Bayes AUC = 0.63, Accuracy 0.58.

Conclusions

Developing a reliable predictive model with only pre-operative variables proved to be difficult, but several preoperative characteristics have a significant impact on the probability of prolonged LOS after CABG. Larger studies are needed to investigate the possibility of developing a reliable predictive model that would help to improve surgical planning.

1024 The Use of the Pedicled Anterolateral Thigh (ALT) Flap for the Reconstruction of Abdominal Wall Defects in High-Risk Patients: A Case Series and Systematic Review

Introduction

The pedicled anterolateral thigh (ALT) flap is considered as a suitable option in complex abdominal wall reconstruction. Its use as a reconstructive option is infrequent in the literature, and to date, there has been no systematic review evaluating its long-term outcomes. We report our experience with the pedicled anterolateral thigh flap for abdominal wall reconstruction in high-risk patients.

Method

A prospective database was created for patients with abdominal wall defects treated with pedicled ALT with extended fascia lata flaps between 2014 and 2017. Patient demographics, aetiology, size, location of defect and post-operative results were reviewed. Abdominal defects were classified into the following zones: 1A, upper midline; 1B, lower midline; 2, upper quadrant; 3, lower quadrant. A systematic review of the literature was conducted using PUBMED and EMBASE.

Results

4 patients (mean age 59.5 years, range 50-65 years) underwent reconstruction with pedicled ALT flaps. 3 flaps developed partial necrosis secondary to infection; 1 flap required surgical debridement, and 2 were managed conservatively. There was one flap failure, due to avulsion of the pedicle during inset. At mean follow up of 2.75 years (range 1 to 4 years) 3 patients have clinical bulging or herniation.

Conclusions

Review of the literature demonstrated 52 patients from 17 case series or reports. The overall infection and partial flap loss rates were both 6%. There were no reported flap failures. Our study demonstrates that the pedicled anterolateral thigh flap is an effective flap option for the repair of large defects of the abdominal wall in high-risk patients.

1158 Summarising the Reporting of Study Outcomes in Robotic Oesophagectomy: A Systematic Review

Introduction

There is an increasing adoption of robotic oesophagectomy in place of standard techniques for oesophageal cancer resection. This is potentially due to its perceived technical benefits and improved short-term outcomes. Consistency in outcome selection, definition and reporting between studies is required for effective evidence synthesis and prevention of research waste. The aim of this review is to perform an in-depth analysis of outcome reporting in robotic oesophagectomy.

Method

Systematic searches were conducted using key words for robotic surgery and oesophageal cancer, from inception to February 2020. Studies reporting any outcome for robotic oesophagectomy were included. Outcomes in each study were recorded verbatim and categorised into twelve domains. Outcomes were independently categorised by two reviewers. Where reported, the follow-up period was also recorded.

Results

Of 954 abstracts screened, 226 full texts were reviewed and 102 included. Only one study was a RCT. A total of 1422 outcomes were reported. Each study had a median of 14 reported outcomes (range 1-25). Outcomes related to complications (n = 578, 99 studies), technical/operative factors (n = 290, 90 studies), and pathology (e.g., resection margin) (n = 197, 83 studies) were reported most frequently. No single outcome, or outcome domain was reported in all studies. No studies used a core outcome set for reporting. Forty-five studies stated a follow-up period, ranging from <1 month to 58 months.

Conclusions

There is significant heterogeneity in the selection and reporting of outcomes in robotic oesophagectomy. This calls for the use of a core outcome set to allow standardisation and transparency of outcome reporting.

Change in opioid and analgesic use for headaches after aneurysmal subarachnoid hemorrhage over time

BACKGROUND

Severe headache, a hallmark of aneurysmal subarachnoid hemorrhage (aSAH), affects up to 90% of patients during hospitalization. Opioids remain the guideline recommended mainstay of acute therapy despite their significant side effects and potential for tolerance and addiction. We evaluated time trends in opioid prescriptions, hypothesizing a decline with increasing recognition of the opioid crisis.

METHODS

We performed a retrospective review of patients with aSAH admitted to a single tertiary care center between 2012 and 2019 and included patients with Hunt-Hess-Grade≤3 who were able to verbalize pain scores. Collected variables included mean and maximum daily headache scores, aneurysm treatment modality, and daily analgesic medication doses.

RESULTS

Of 340 patients with aSAH, 114 (86 from 2012-2016 and 28 from 2017-2019) were included. Of the included patients, 86/114 (75.4%) were female. Patients in the 2012-2016 had a median age of 55 compared to 63 in the 2017-2019 group (P=0.02). Otherwise, there was no significant difference in demographic data including time in hospital, treatment option utilized, or aneurysm characteristics. Maximal daily headache score ranged from 6 to 8 for 2012-2016 and 5 to 8 for 2017-2019 cohorts. Average oral morphine equivalents (in mg) administered during hospitalization were similar between groups (2012-2016: 251±345 95% CI [178,323]; 2017-2019: 207±237 95% CI [119,295]; P=0.319). When prescribed, doses of opioids provided at discharge were less in the more recent group (2012-2016: 84.4±78.9 95% CI [57.5, 111]; 2017-2019: 38.1±20.2 95% CI [33.7, 42.5]; P=0.004) CONCLUSION: Despite recognition of important drawbacks of opioid use for headache control, and efforts to reduce opioid use during hospitalization, we found that utilization during hospitalization for SAH did not decrease over time. Maximal headache scores remained similar in the studied time periods, indicative of insufficient pain relief. This points out a pressing need to further investigate alternative opioid and narcotic sparing strategies for patients with SAH.

P–182 The mechanism of mouse embryo hatching and the impact of laser drilling the zona pellucida: an RNA sequencing study

Study question

What is the mechanism of embryo hatching? Will laser-assisted zona pellucida (ZP) drilling alter the embryonic transcriptome?

Summary answer

Hatching is an ATP-dependent process. Hatching is also associated with Rho-mediated signaling. Laser-assisted ZP drilling might cause alternation in embryo metabolism.

What is known already

Embryo hatching is a vital process for early embryo development and implantation. Animal data suggests that hatching is the result of multiple factors, such as mechanical pressure, protease activation, and the regulation of maternal secretions. However, little is known about the regulatory signaling mechanisms and the molecules involved. In addition, despite the extensive use of laser-assisted ZP drilling in the clinic, the safety profile of this technique at molecular level is very sparse. The impact of this technique on the embryonic transcriptome has not been studied systematically.

Study design, size, duration

Eighty mouse embryos were randomly divided into a laser ZP drilling group (n = 40) and an untreated group (n = 40). After treatment, embryos were cultured in vitro for two days. Then, hatching blastocyst (n = 8) and pre-hatching blastocyst (n = 8) from the untreated group, and the hatching blastocyst from the treatment group (n = 8) were processed for RNA sequencing (RNA-seq).

Participants/materials, setting, methods

Cryopreserved 8-cell stage mouse embryos (B6C3F1 × B6D2F1) were thawed, and a laser was used to drill the embryo ZP in the treatment group. Next, the treated and untreated embryos were individually cultured in vitro to the E4.5 blastocyst stage. The resulting blastocysts were lysed individually and used for subsequent cDNA library preparation and RNA-seq. Following data quality control and alignment, the RNA-seq data were processed for differentially expressed gene analysis and downstream functional analysis.

Main results and the role of chance

According to the RNA-seq data, 275 differentially expressed genes (DEGs) (230 up-regulated and 45 down-regulated, adjusted P < 0.05) were identified when comparing hatching and pre-hatching blastocysts in the control groups. Analysis suggested that the trophectoderm is the primary cell type involved in hatching, and revealed the potential molecules causing increased blastocyst hydrostatic pressure (Aqp3 and Cldn4). Functional enrichment analysis suggested that ATP metabolism and protein synthesis were activated in hatching blastocysts. DEGs were found to be significantly enriched in several gene ontology terms, particularly in terms of the organization of the cytoskeleton and actin polymerisation (P < 0.0001). Furthermore, according to QIAGEN ingenuity pathway analysis results, Rho signaling was implicated in blastocyst hatching (Actb, Arpc2, Cfl1, Myl6, Pfn1, Rnd3, Septin9, z-score=2.65, P < 0.0001). Moreover, the potential role of hormones (estrogen (z-score=2.24) and prolactin (z-score=2.4)) and growth factors (AGT (z-score=2.41) and FGF2 (z-score=2.213)) were implicated in the hatching process as indicated by the upstream regulator analysis. By comparing the transcriptome between laser-treated and untreated hatching blastocysts, 47 DEGs were identified (adjusted P < 0.05) following laser-assisted ZP drilling. These genes were enriched in metabolism-related pathways (P < 0.05), including the lipid metabolism pathway (Mvd, Mvk, Aacs, Gsk3a, Pik3c2a, Aldh9a1) and the xenobiotic metabolism pathway (Aldh18a1, Aldh9a1, Keap1, and Pik3c2a).

Limitations, reasons for caution

Findings in mouse embryos may not be fully representative of human embryos. Furthermore, the mechanism of hatching revealed here might only reflect the hatching process of embryos in vitro. Further studies are now necessary to confirm these findings in different conditions and species to determine their clinical significance. Wider implications of the findings: Our study profiled the mouse embryo transcriptome during in vitro hatching, identified potential key genes and mechanisms for future study. In addition, for the first time, we revealed the impact of laser-assisted ZP drilling on the transcriptome, this may help us to assess and improve the existing technique.

Trial registration number

Not applicable

P-798 Fertility preservation in pre-pubertal boys with cancer: A three-dimensional prepubertal testicular organoid for in vitro spermatogonial stem cell propagation and spermatogenesis

Study question

Can a three-dimensional (3D) prepubertal testicular organoid be formed and provide an in vitro microenvironment for spermatogonial stem cells (SSCs) maintenance and future spermatogenesis?

Summary answer

Primary cells extracted from immature testicular tissue (ITT) or SSCs can be grown long-term as 3D organoids, providing the potential for in vitro study.

What is known already

Aggressive cancer treatments, such as chemo- or radiotherapy, can leave young prepubertal boys infertile. Such patients are recommended to undergo the cryopreservation of testicular material to protect future fertility. Within the testes, the specialized 3D structure and direct cell-to-cell interactions play a critical role in the proliferation and development of SSCs. Over recent decades, 3D culture systems and organoids have been used to culture cells in vitro, however, a system that allows investigations into testicular organogenesis in vitro, and its impact on the SSC niche, has yet to be developed.

Study design, size, duration

This study aims to develop a 3D organoid culture system to support the proliferation of SSCs and spermatogenesis. Primary bovine ITT cells and enriched SSCs were isolated and 3D organoids were generated by in vitro culture for up to 40 days. Organoid formation was observed after using different foundation cells seeded at different densities and cultured in medium containing gonadotropic supplements.

Participants/materials, setting, methods

Post-thaw bovine ITTs (2 weeks-of-age) were dissociated using two-step enzymatic digestion. Enriched SSCs were selected by Percoll gradients and differential plating. Viability and apoptosis were evaluated by trypan blue staining and TUNEL assays, respectively. SSCs were evaluated immunocytochemically for germ-cell markers (PGP-9.5, PLZF) and Sertoli cell markers (Vimentin, Sox9). Expression levels of SSCs and spermatogenesis-related genes (Plzf, Gfrα-1, Nanog, Oct4, Stra8, Thy1) were determined by real-time quantitative polymerase chain reaction (RT-qPCR).

Main results and the role of chance

The viability of digested cells from thawed ITTs was 78.667% ± 2.03. Total testicular cells (<10% SSCs) and enriched SSCs(>50% SSCs) were observed to self-assemble into structurally complex organoids recapitulating the cell type compartmentalization of the testis, in a 3D Matrigel-based culture system with 10% knockout serum replacement (KSR) culture medium, but not with 10% fetal bovine serum(FBS) medium. Testicular organoids were found to exhibit either a grape-like structure and a round-shape structure. Cytoplasmic extensions of spermatogonia/Sertoli cells were in contact with each other within a forming colony. Organoids were formed faster and larger when seeded at a final concentration of 1.5 × 106 cells/ml, compared to 5 × 105 cells/ml and 1.5 × 105 cells/ml. Organoids grew to a diameter of 400 μm within 10 - 15 days and were passaged by mechanical disruption at a ratio of 1:3 every 7 - 10 days. Immunocytochemistry results showed that clusters of PGP9.5 and PLZF-positive cells were present within the organoids. The expression of selected germ cell and spermatogenesis markers in the testicular organoids closely resembled that of primary testicular cells for up to 20 days of culture.

Limitations, reasons for caution

We used calves (2 weeks-of-age) as an animal model to study testicular organoids. This tissue may act differently than human tissues and may not fully represent prepuberty. Furthermore, we only evaluated gene expression levels for selected markers that may not represent the full functional capability of germ cells.

Wider implications of the findings

Testicular organoids, as an in vitro bioengineering testicular model, could potentially be used to study testicular tissue development, cellular interactions, endocrinology, and spermatogenesis, in the laboratory but may also be applied for clinical purposes in the future.

Trial registration number

University of Oxford

P–798 Fertility preservation in pre-pubertal boys with cancer: A three-dimensional prepubertal testicular organoid for in vitro spermatogonial stem cell propagation and spermatogenesis

Study question

Can a three-dimensional (3D) prepubertal testicular organoid be formed and provide an in vitro microenvironment for spermatogonial stem cells (SSCs) maintenance and future spermatogenesis?

Summary answer

Primary cells extracted from immature testicular tissue (ITT) or SSCs can be grown long-term as 3D organoids, providing the potential for in vitro study.

What is known already

Aggressive cancer treatments, such as chemo- or radiotherapy, can leave young prepubertal boys infertile. Such patients are recommended to undergo the cryopreservation of testicular material to protect future fertility. Within the testes, the specialized 3D structure and direct cell-to-cell interactions play a critical role in the proliferation and development of SSCs. Over recent decades, 3D culture systems and organoids have been used to culture cells in vitro, however, a system that allows investigations into testicular organogenesis in vitro, and its impact on the SSC niche, has yet to be developed.

Study design, size, duration

This study aims to develop a 3D organoid culture system to support the proliferation of SSCs and spermatogenesis. Primary bovine ITT cells and enriched SSCs were isolated and 3D organoids were generated by in vitro culture for up to 40 days. Organoid formation was observed after using different foundation cells seeded at different densities and cultured in medium containing gonadotropic supplements.

Participants/materials, setting, methods

Post-thaw bovine ITTs (2 weeks-of-age) were dissociated using two-step enzymatic digestion. Enriched SSCs were selected by Percoll gradients and differential plating. Viability and apoptosis were evaluated by trypan blue staining and TUNEL assays, respectively. SSCs were evaluated immunocytochemically for germ-cell markers (PGP–9.5, PLZF) and Sertoli cell markers (Vimentin, Sox9). Expression levels of SSCs and spermatogenesis-related genes (Plzf, Gfrα–1, Nanog, Oct4, Stra8, Thy1) were determined by real-time quantitative polymerase chain reaction (RT-qPCR).

Main results and the role of chance

The viability of digested cells from thawed ITTs was 78.667% ± 2.03. Total testicular cells (<10% SSCs) and enriched SSCs(>50% SSCs) were observed to self-assemble into structurally complex organoids recapitulating the cell type compartmentalization of the testis, in a 3D Matrigel-based culture system with 10% knockout serum replacement (KSR) culture medium, but not with 10% fetal bovine serum(FBS) medium. Testicular organoids were found to exhibit either a grape-like structure and a round-shape structure. Cytoplasmic extensions of spermatogonia/Sertoli cells were in contact with each other within a forming colony. Organoids were formed faster and larger when seeded at a final concentration of 1.5 × 106 cells/ml, compared to 5 × 105 cells/ml and 1.5 × 105 cells/ml. Organoids grew to a diameter of 400 μm within 10 - 15 days and were passaged by mechanical disruption at a ratio of 1:3 every 7 - 10 days. Immunocytochemistry results showed that clusters of PGP9.5 and PLZF-positive cells were present within the organoids. The expression of selected germ cell and spermatogenesis markers in the testicular organoids closely resembled that of primary testicular cells for up to 20 days of culture.

Limitations, reasons for caution

We used calves (2 weeks-of-age) as an animal model to study testicular organoids. This tissue may act differently than human tissues and may not fully represent prepuberty. Furthermore, we only evaluated gene expression levels for selected markers that may not represent the full functional capability of germ cells.

Wider implications of the findings: Testicular organoids, as an in vitro bioengineering testicular model, could potentially be used to study testicular tissue development, cellular interactions, endocrinology, and spermatogenesis, in the laboratory but may also be applied for clinical purposes in the future.

Trial registration number

University of Oxford

P–265 Investigating the nanotoxicity of solid silica nanoparticles in gametes following in vitro exposure

Study question

Do solid silica nanoparticles qualify as a new research tool for the in vitro transfer of compounds into gametes prior to Assisted Reproductive Technology (ART).

Summary answer

Solid silica nanoparticles (SSNPs) could be used as an intra-gamete delivery system to deliver therapeutic biomolecules into gametes prior to ART.

What is known already

Sperm-mediated gene transfer (SMGT) results in the production of transgenic embryos; however, the success rate of this technique is low. Nanoparticles are an efficient intra-cellular delivery system in vitro. Naturally cell-secreted nanoparticles are involved in the development of gametes. Mesoporous silica nanoparticles have been shown to carry large amounts of compounds and to interact with gametes without toxic effects, thus providing an alternative to naturally secreted nanoparticles. However, this technique is associated with some limitations, such as the size of these nanoparticles. SSNPs can be synthesised on a smaller nanoscale, thus providing higher potential to penetrate gametes and delivering biomolecules.

Study design, size, duration

This was an experimental in vitro study that investigated the effects of SSNPs on the motility of boar sperm and the degeneration of hamster oocytes, as determined by ooplasm shrinkage.

Participants/materials, setting, methods

SSNPs (20 nm) were conjugated with fluorescein diacetate–5-maleimide (FDA5M), a fluorescent protein. FDA5M-labelled SSNPS were incubated with boar sperm (N = 3) at 10 and 30µg/ml/107 sperm for four-hours. Motility parameters were assessed by computer-assisted sperm analysis (CASA). Binding potential was evaluated by fluorescent microscopy. Hamster oocytes (7 oocytes/group) were incubated with FDA5M-labelled SSNPs at 100, 150, and 300µg/ml, for two-hours; ooplasm shrinkage was evaluated. Time/matched control sperm was incubated in phosphate-buffered saline and oocytes in KSOM.

Main results and the role of chance

Exposure to FDA5M-labelled SSNPs did not affect total or progressive sperm motility (P = 0.6735 and 0.9606, respectively), average-path velocity or straight-line velocity after 4-hours of incubation (P = 0.7459 and 0.8696, respectively) compared to controls. SSNPs at 10 µg/ml significantly increased sperm curvilinear velocity after 1-hour (P = 0.0495) and linearity and straightness after 4-hours (P = 0.0389 and 0.0312, respectively). SSNPs at 30 µg/ml significantly increased sperm linearity after 3- and 4-hours (P = 0.0384 and 0.005, respectively). The proportion of sperm showing green fluorescence was significantly higher in the 30µg/ml dose of SSNPs than the 10µg/ml dose after 4-hours (P < 0.00001). In oocytes, the zona pellucida remained morphologically intact and the ooplasm exhibited green fluorescence. The ooplasm of 42% of the oocytes at 300µg/ml showed ooplasm shrinkage (a sign of degeneration); no oocytes showed shrinkage at doses of 100 and 150µg/ml of SSNPs. The green fluorescence in the sperm head and the ooplasm indicated the ability of SSNPs to spontaneously interact non-invasively with these gametes either by surface association or by cell-internalisation. This could provide a safe and non-invasive intra-gamete delivery system for research purposes and clinical therapy. This system could be used to deliver specific agents into gametes prior to ART to improve outcomes.

Limitations, reasons for caution

The SSNPs are non-biodegradable; it remains unknown as to how gametes or embryos might react with SSNPs over long time periods. The nanotoxicity of SSNPs has not yet been investigated over the long term. SSNPs have still to be tested with embryos to evaluate their effect on embryonic development.

Wider implications of the findings: SSNPs could be functionalised to target the nucleus of mammalian gametes and embryos to act as a carrier for oligonucleotides and genes to correct chromosomal abnormalities and to provide genetic therapy in these gametes and embryos to treat hereditary diseases before intra-uterine transfer.

Trial registration number

Not applicable

Autism spectrum disorder in females with fragile X syndrome: a systematic review and meta-analysis of prevalence

BACKGROUND

Whilst up to 60% of males with fragile X syndrome (FXS) meet criteria for autism spectrum disorder (ASD), the prevalence and nature of ASD in females with FXS remains unclear.

METHOD

A systematic literature search identified papers reporting ASD prevalence and/or symptomatology in females with FXS.

RESULTS AND CONCLUSION

Meta-analysis suggested that rates of ASD for females with FXS are reliably higher than for females in the general population (a random effects model estimated weighted average prevalence at 14%, 95% CI 13-18%). Whilst papers highlighted a number of social and repetitive difficulties for females with FXS, characteristic profiles of impairment are not clear. Possible associations between ASD traits and IQ, and between ASD and levels of fragile X mental retardation protein, are suggested, but data are equivocal.